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排序方式: 共有792条查询结果,搜索用时 15 毫秒
721.
Agata Krakowska Witold Reczyski Tomasz Krakowski Karolina Szewczyk Wodzimierz Opoka Boena Muszyska 《Molecules (Basel, Switzerland)》2021,26(17)
Agaricus bisporus (J.E. Lange) Imbach is one the most popular species of edible mushrooms in the world because of its taste and nutritional properties. In the research, repeatability of accumulation of bioelements and biomass yield in experimentally chosen in vitro culture medium, was confirmed. The in vitro cultures were conducted on the modified Oddoux medium enriched with bioelements (Mg, Zn, Cu, Fe). The aim of the study was to create an effective method of sampling, which enabled non-invasive monitoring of metals concentrations changes in the medium, during increase of biomass in in vitro cultures. The first, indirect method of sampling was applied. The non-invasive probe (a dipper) for in vitro culture was used; hence, the highest biomass increase and metals accumulation were gained. The method also guaranteed culture sterility. The second method, a direct one, interfered the in vitro culture conditions and growth of mycelium, and as a consequence the lower biomass increase and metals’ accumulation were observed. Few cases of contaminations of mycelium in in vitro cultures were observed. The proposed method of non-invasive sampling of the medium can be used to monitor changes in the concentrations of metals in the medium and their accumulation in the mycelium in natural environment. Changes in concentrations of the selected metals over time, determined by the method of atomic absorption spectrometry, made it possible to correlate the obtained results with the specific stages of A. bisporus mycelium development and to attempt to explain the mechanism of sampling metals from the liquid substrate. 相似文献
722.
T. Toliński A. Kowalczyk E. Ga?o J. Kova? 《Journal of magnetism and magnetic materials》2009,321(9):1121-1124
The magnetic, thermodynamic and electronic structure properties are discussed for the CeNi4Cr compound. The X-ray photoemission spectra (XPS) provide an evidence of a mixed valence behavior with the occupancy of the f states nf=0.89 and their hybridization with the conduction electrons Δ=30 meV. These values reproduce well the magnetic susceptibility χ(T=0), which is enhanced compared to similar CeNi4M (M=Al, B, Cu) compounds. In combination with a slightly increased electronic specific heat coefficient (up to 100 mJ mol−1 K−2), this compound can be classified as being on the border of the heavy fermion and mixed valence behavior. Using a small magnetic field in the χ(T) measurements reveals a presence of magnetically ordered impurity phase, which is easily damped by higher fields and it is shown that the contribution of this phase is minor. The question of the dependence of the electronic specific heat coefficient on the magnetic field is also addressed and the observations agree well with theoretical predictions based on the Anderson model. 相似文献
723.
I. Sankowska Ch. Droste E. Grodner T. Morek J. Srebrny A. A. Pasternak J. Kownacki P. Napiorkowski S. G. Rohoziński M. Kowalczyk M. Kisieliński R. Kaczarowski E. Ruchowska 《The European Physical Journal A - Hadrons and Nuclei》2008,37(2):169-175
Lifetimes of the yrast levels with spins I π = 23/2? to 39/2? in 129La produced via the 120Sn(14N, 5n) reaction at a beam energy of 77MeV have been measured by the Doppler shift attenuation method. The properties of the studied levels belonging to the πh11/2 band were compared with the theoretical predictions obtained in the framework of the core quasi-particle coupling model. It is suggested that the rigid-rotor model used to describe the cores is too simplified as the even-even nuclei from the A ~ 130 region are susceptible to shape deformation. Reasonable agreement was obtained with the phenomenological cores based on the experimental data of 128Ba. 相似文献
724.
Kowalczyk A 《Cryo letters》2008,29(3):199-208
Changes in the morphology and fertilising ability of Japanese quail spermatozoa were studied after semen dilution, equilibration and freezing-thawing process in order to determine the optimal diluent, cryoprotectant and the freezing-thawing method. Subsequent stages of quail semen cryopreservation caused significant decline in spermatozoa morphology and their ability to fertilise the ovum. Semen dilution with Lake's extender alone reduced the number of morphologically normal spermatozoa and decreased their fertilising ability. Dimethylacetamide (DMA) was the least detrimental but equilibration of quail spermatozoa with this cryoprotectant caused further decline in the number of morphologically normal cells. However, despite these changes, after artificial insemination with semen equilibrated with DMA 25.8 percent of fertile eggs were obtained. Further loss in the number of normal spermatozoa was observed following the freezing-thawing process. Of the two investigated freezing-thawing methods, the rapid rate (60 C/min) appeared less detrimental to spermatozoa morphology and their ability to fertilize the ovum than the "slow" rate. Also the number of sperm holes appearing in the inner perivitelline layer and the number of spermatozoa trapped in the outer perivitelline layer of the ovum was higher after the rapid than the 'slow' freezing-thawing procedure. Nevertheless, both rates did not yield any fertile eggs. 相似文献
725.
We describe how the simple phase difference averaging causes a systematic bias in the velocity estimation obtained by phase-resolved Fourier domain optical coherence tomography (FdOCT). The magnitude of this bias depends on the signal-to-noise ratio as well as proximity of the measured velocity to the limits of the velocity range. We demonstrate the proper way of data processing, which enables obtaining velocity values free of this error. We validate the improved technique by measurements of flow velocity in glass capillaries, in human retinal vessels, and we compare the results with those obtained by standard phase-resolved FdOCT. 相似文献
726.
Mu‐Huai Fang Sebastian Mahlik Agata Lazarowska Marek Grinberg Maxim S. Molokeev Hwo‐Shuenn Sheu Jyh‐Fu Lee Ru‐Shi Liu 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(23):7849-7854
In this study, a series of Sr(LiAl3)1?x(SiMg3)xN4:Eu2+ (SLA‐SSM) phosphors were synthesized by a solid‐solution process. The emission peak maxima of SLA‐SSM range from 615 nm to 680 nm, which indicates structural differences in these materials. 7Li solid‐state NMR spectroscopy was utilized to distinguish between the Li(1)N4 and Li(2)N4 tetrahedra in SLA‐SSM. Differences in the coordination environments of the two Sr sites were found which explain the unexpected luminescent properties. Three discernible morphologies were detected by scanning electron microscopy. Temperature‐dependent photoluminescence and decay times were used to understand the diverse environments of europium ions in the two strontium sites Sr1 and Sr2, which also support the NMR analysis. Moreover, X‐ray absorption near‐edge structure studies reveal that the Eu2+ concentration in SLA‐SSM is much higher than that in in SrLiAl3N4:Eu2+ and SrSiMg3N4:Eu2+ phosphors. Finally, an overall mechanism was proposed to explain the how the change in photoluminescence is controlled by the size of the coordinated cation. 相似文献
727.
Agata Smoktunowicz 《Inventiones Mathematicae》2006,164(3):635-640
Let K be a field, and let R=⊕n∈NRn be a finitely generated, graded K-algebra which is a domain. It is shown that R cannot have Gelfand-Kirillov dimension strictly between 2 and 3.
Mathematics Subject Classification (2000) 16D90, 16P40, 16S80, 16W50 相似文献
728.
Agata Ciabattoni 《Archive for Mathematical Logic》2005,44(4):435-457
We perform a proof-theoretical investigation of two modal predicate logics: global intuitionistic logic GI and global intuitionistic fuzzy logic GIF. These logics were introduced by Takeuti and Titani to formulate an intuitionistic set theory and an intuitionistic fuzzy set theory together with their metatheories. Here we define analytic Gentzen style calculi for GI and GIF. Among other things, these calculi allows one to prove Herbrands theorem for suitable fragments of GI and GIF.Work Supported by C. Bühler-Habilitations-Stipendium H191-N04, from the Austrian Science Fund (FWF). 相似文献
729.
M. Wolińska-Cichocka J. Kownacki W. Urban E. Ruchowska W. A. Płóciennik B. Bekman Ch. Droste W. Gast R. Lieder W. Meczyński M. Kisieliński A. Kordyasz M. Kowalczyk P. Kowina J. Iwanicki T. Morek J. Perkowski J. Srebrny A. Stolarz J. Styczeń 《The European Physical Journal A - Hadrons and Nuclei》2005,24(2):259-274
Excited states in 110Sn and 111Sn nuclei have been investigated using in-beam -ray spectroscopic methods. An 16O beam with an energy of 60-80MeV was used to bombard a 98Mo target. On the basis of the relative excitation functions, -ray angular distributions, - and -time distributions, -ray multiplicity and total energy data, the level schemes of 110Sn and 111Sn have been studied and extended up to Eexc 11.5MeV, I = 24, and Eexc 11.1MeV and I = (51/2), respectively. An extension of the intruder, g.s. and negative-parity bands, as well as 5 new band-like structures are proposed in 110Sn. The nature of newly introduced collective band 8 as well as 10+ states fed in the decay of the collective band is discussed. In the 111Sn nucleus an intruder band based on the 23/2- state has been reinvestigated and the extension of the g.s. band and second negative-parity band is given. Evidence for neutron-core coupling in 111Sn is found. The structure and systematics of excited states in light Sn isotopes is discussed. 相似文献
730.
S. K. Shakshooki F. Masaodi A. Dehair L. Szirtes J. Kowalczyk 《Journal of Radioanalytical and Nuclear Chemistry》1989,132(2):251-260
Mixed amorphous, glassy type, zirconium-titanium arsenate (ZrTiAs) and hafniumtitanium arsenate (HfTiAs) have been prepared. The composition and exchange capacity of the prepared samples were investigated in comparison with pure zirconium, titanium and hafnium arsenates, respectively. For the samples the ZrxTi(1-x)(HAsO4)2·2H2O and the HfxTi(1-x)(HAsO4)2·2H2O compositions (where 0<x<1) were found. The exchange capacity values were found less than those for pure arsenates, but they do not change their values under the effect of high dose of gamma-radiation. 相似文献