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排序方式: 共有140条查询结果,搜索用时 31 毫秒
41.
Loba Aleksandra Waroszewski Jarosław Tikhomirov Dmitry Calitri Fancesca Christl Marcus Sykuła Marcin Egli Markus 《Journal of Soils and Sediments》2021,21(8):2952-2968
Journal of Soils and Sediments - Loess landscapes are highly susceptible to soil erosion, which affects soil stability and productivity. Erosion is non-linear in time and space and determines... 相似文献
42.
Marcin Wysokowski ?ukasz Klapiszewski Dariusz Moszyński Przemys?aw Bartczak Tomasz Szatkowski Izabela Majchrzak Katarzyna Siwińska-Stefańska Vasilii V. Bazhenov Teofil Jesionowski 《Marine drugs》2014,12(4):2245-2268
Novel, functional materials based on chitin of marine origin and lignin were prepared. The synthesized materials were subjected to physicochemical, dispersive-morphological and electrokinetic analysis. The results confirm the effectiveness of the proposed method of synthesis of functional chitin/lignin materials. Mechanism of chitin modification by lignin is based on formation of hydrogen bonds between chitin and lignin. Additionally, the chitin/lignin materials were studied from the perspective of waste water treatment. The synthetic method presented in this work shows an attractive and facile route for producing low-cost chitin/lignin biosorbents with high efficiency of nickel and cadmium adsorption (88.0% and 98.4%, respectively). The discovery of this facile method of synthesis of functional chitin/lignin materials will also have a significant impact on the problematic issue of the utilization of chitinous waste from the seafood industry, as well as lignin by-products from the pulp and paper industry. 相似文献
43.
Ulkowski M Musialik M Litwinienko G 《Journal of agricultural and food chemistry》2005,53(23):9073-9077
The oxidation of linolenic acid (LNA) and soy lecithin was studied by differential scanning calorimetry (DSC) with linear programmed heating rates (non-isothermal mode). The interpretation of the shape of DSC curves is discussed, and it has been concluded that temperatures of the extrapolated start of heat release are the most reliable data for the rapid estimation of the oxidative stability of lipid materials. The Ozawa-Flynn-Wall method was used to calculate the kinetic parameters of the process: for LNA autoxidation the activation energy, Ea, and pre-exponential factor, Z, are 66 +/- 4 kJ/mol and 1.5 x 10(7) s(-1), respectively, and the autoxidation of lecithin is described by Ea = 98 +/- 6 kJ/mol and Z = 9.1 x 10(10) s(-1). Values of Ea and Z can be applied for calculation of the overall first-order rate constant of autoxidation at various temperatures, k(T). For the two studied lipids the comparison of k(T) values shows the inversion of their oxidative stabilities; that is, below 167 degrees C lecithin is more stable than LNA, k(T)lecithin < k(T)LNA, and above that temperature (termed the isokinetic temperature) k(T)lecithin > k(T)LNA. The calculated inversion of oxidative stabilities can be an explanation of similar observations for other pairs of lipids if the results of accelerated tests measured at temperatures above 100 degrees C are compared with the results obtained at temperatures below 100 degrees C. 相似文献
44.
Dr Marcin Pietrzykowski Wojciech Krzaklewski 《Archives of Agronomy and Soil Science》2013,59(5):473-483
Abstract The work presents study results on the formation of humus horizons, the accumulation of organic carbon and nitrogen as well as humus composition in successional and reclaimed soils in a sand mine cast in southern Poland. Research plots were designed in chronosequence: 5, 17, 20 and 25 years. Increased thickness of humus horizon and accumulation of organic carbon was reported both in successional soils and in reclaimed soils. However, in corresponding age groups of reclaimed soils these characteristics were two times as high as in successional soils. The estimated accumulation rate of organic carbon (Corg) was three times higher and total nitrogen (Nt) five times higher in reclaimed soils than in successional soils. In both types of soils there was an increase in the amount of carbon trapped with humic and fulvic acid (CHa + CFa) and structure of humic acids. Studies indicated that reclamation treatment significantly accelerated soil-formation in opencast sand mine. 相似文献
45.
46.
The mechanisms for translocation of heavy metals from soil to epigeal mosses were investigated. The first mechanism was demonstrated
for 137Cs and involved the uplifting of the pollutant-containing dust from the soil, followed by the local secondary deposition on
surfaces of epigeal mosses and epiphytic lichens. The second mechanism involved the diffusion of metal cations from the soil
through water wetting the moss into the gametophyte. The mechanism was demonstrated by measuring the electric conductance
of wetted gametophytes with single ends immersed in solutions of Cu and Na salts. In addition, the concentrations of Cu and
Cd were compared in moss samples exposed to the natural soil and to the soil contaminated with the metals. The exposition
to the contaminated soil resulted in the statistically significant increase of metal concentrations in the gametophytes. 相似文献
47.
Edward Witkowski Jacek Waga Krystyna Witkowska Marcin Rapacz Magdalena Gut Amelia Bielawska Helena Luber Adam J. Lukaszewski 《Euphytica》2008,159(3):377-384
Subunits of high molecular weight glutenins strongly influence wheat bread making quality and can be associated with important
agronomic traits. Polish winter wheats show a significant quantitative dominance of the null allele over the coding alleles of the Glu-A1 locus. To identify the causes of such skewed distribution, 116 F5 lines obtained from six cross combinations were analyzed for their HMW glutenin subunits and 11 agronomic characteristics,
such as plant height and uniformity, leaf blotch and leaf rust resistance, grain yield per plot, number of grains per ear,
grain yield per ear, 1000 kernel weight, frost tolerance, total protein content and the SDS-sedimentation value. The SDS-sedimentation
value, resistance to leaf blotch and frost tolerance showed statistically significant associations with the status of the
Glu-A1 locus. It appears that chromosome 1A with the null allele at Glu-A1 carries a closely linked locus responsible for frost tolerance. With early strong selection for winter hardiness, the null
allele of Glu-A1 becomes fixed in advanced breeding materials despite its strong negative impact on the end use quality. 相似文献
48.
Mostafa Farhadi Mulualem Tigabu Marcin Pietrzykowski Darius Danusevičius Per Christer Odén 《New Forests》2017,48(5):629-642
Authentication of seed provenance is an importance issue to avoid the negative impact of poor adaptation of progenies when planted outside their natural environmental conditions. The objective of this study was to evaluate the potential of near infrared (NIR) spectroscopy as rapid and non-destructive method for authentication of Picea abies L. Karst seed provenances. For this purpose, five seed lots from Sweden, Finland, Poland and Lithuania each were used. NIR reflectance spectra were recorded on individual seeds (n = 150 seeds × 5 seed lots × 4 provenances = 3000 seeds) using XDS Rapid Content Analyzer from 780 to 2500 nm with a resolution of 0.5 nm. Classification model was developed by orthogonal projection to latent structures-discriminant analysis. The performance of the computed classification model was validated using two test sets—internal (the same seed lots as the model but excluded during model development; n = 600 seeds) and external (seed lots not included in the model; n = 1158 seeds). For the internal test, the model correctly recognized 99% of Swedish, Finnish and Polish samples and 97% of Lithuanian seeds. For the external test samples, the model correctly assigned 81% of Swedish, 96% of Finnish, 98% of Lithuanian and 93% of Polish seeds to their respective classes. The mean classification accuracy was 99 and 95% for internal and external test set, respectively. The spectral differences among seed lots were attributed to differences in chemical composition of seeds, presumably fatty acids and proteins, which are the dominant storage reserves in P. abies seeds. In conclusion, the results demonstrate that NIR spectroscopy is a very promising method for monitoring putative seed provenances and in seed certification. 相似文献
49.
Denoeud F Henriet S Mungpakdee S Aury JM Da Silva C Brinkmann H Mikhaleva J Olsen LC Jubin C Cañestro C Bouquet JM Danks G Poulain J Campsteijn C Adamski M Cross I Yadetie F Muffato M Louis A Butcher S Tsagkogeorga G Konrad A Singh S Jensen MF Cong EH Eikeseth-Otteraa H Noel B Anthouard V Porcel BM Kachouri-Lafond R Nishino A Ugolini M Chourrout P Nishida H Aasland R Huzurbazar S Westhof E Delsuc F Lehrach H Reinhardt R Weissenbach J Roy SW Artiguenave F Postlethwait JH Manak JR Thompson EM 《Science (New York, N.Y.)》2010,330(6009):1381-1385
Genomes of animals as different as sponges and humans show conservation of global architecture. Here we show that multiple genomic features including transposon diversity, developmental gene repertoire, physical gene order, and intron-exon organization are shattered in the tunicate Oikopleura, belonging to the sister group of vertebrates and retaining chordate morphology. Ancestral architecture of animal genomes can be deeply modified and may therefore be largely nonadaptive. This rapidly evolving animal lineage thus offers unique perspectives on the level of genome plasticity. It also illuminates issues as fundamental as the mechanisms of intron gain. 相似文献
50.