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41.
Branimir Urlić Gvozden Dumičić Smiljana Goreta Ban Marija Romić 《Journal of plant nutrition》2016,39(3):389-398
Understanding the mechanisms of phosphorus (P)-use efficiency (PUE) may contribute to enhancing crop P nutrition because species growth variability at low-P is well known. The experiment was carried out to evaluate the response of kale genotypes to different P supply in randomized block design in three replications. Low-P supply led to a decrease in most parameters, whereas an increase was recorded in root growth parameters. Genotypes differed in shoot dry weight (DW), leaf area, root length and area, and shoot and root P content and concentration. Root traits significantly positively correlated with PUE. Genotypes Red Russian (RR) and IJK 17 were superior in terms of shoot DW production at low P supply, and had the highest uptake efficiency. Genotypes IJK 17 and 81 had the highest P utilization efficiency, while Vates blue curled (VBC) showed the lowest PUE. Genotypes had similar shoot P content and concentration at low P supply, but large PUE differences, implying the importance of P utilization efficiency. 相似文献
42.
The influence of mesoscale weather patterns on the chemical composition of daily precipitation samples is analysed. The data of pH, sulphur from sulphates and total nitrogen are analysed for two rural sites: Plitvice station in forested part of Central Croatia (1981 to 1990) and Puntijarka suburban station on the mountain near Zagreb, the capital of Croatia (1982–1991). The two prevailing weather types in precipitation days are selected and the comparison of chemical composition of precipitation is made for each of them. The frequency distributions of pH, sulphur and nitrogen show that concentration of major ions in precipitation apparently depends on the regional scale weather type. It is shown that the seasonal variation of deposition is related to the seasonal variation in precipitation amount. In both weather types Plitvice receives more pollution than Puntijarka that is closer to urban and industrial pollution sources. Both locations are under the prevailing influence of regional pollution sources. 相似文献
43.
Igor Grebenščikov 《Genetic Resources and Crop Evolution》1985,33(2):183-198
Zusammenfassung Im Laufe von 16 Jahren (1968–1983) wurden für Rohproteinanalysen des Korns aus dem Gaterslebener Maissortiment zufällige Stichproben von etwa 40 bis 80 Stämmen jährlich entnommen. Für die Mittelwerte und Varianzen der Stichproben wurden die 95 %-Vertrauensbereiche geschätzt (Abb. 1 und 3). Die meisten Jahresmittelwerte für den Gehalt an Rohprotein (RP %) liegen zwischen 11,4 und 12,1 % (ohne Puff- und Zuckermais). Signifikante Abweichungen wurden nur selten beobachtet. Die jährlichen Variabilitätskoeffizienten liegen hier bei etwa 12 %, bei vielen anderen Merkmalen dagegen um 30 %. Die Schätzung der Korrelation zwischen RP % und TKM im Durchschnitt von 13 Jahren (wieder ohne Puff- und Zuckermaise) ergab einen nicht signifikanten Wert vonr
s
=-0,04. Ferner wurden zahlreiche Varianzanalysen (Modell II) mit Schätzung von Varianzkomponenten (auch in %) für die Faktoren Stamm und Jahr durchgeführt, die dafür sprechen, daß für eine befriedigende Erfassung von RP %-Variabilität 3 bis 4 Kolben je Stamm in 3 bis 4 Jahren nötig sind. Am Schluß sind 40 Gaterslebener Sortimentsnummern mit mindestens vierjährigen Rohprotein-Mittelwerten über 12 % und den dazugehörigen 95 %-Vertrauensbereichen angeführt.
Variability of the curde protein content in the Gatersleben maize collection
Summary Random samples of a number between 40 and 80 strains out of the Gatersleben maize collection were taken every of 16 years (1968–1983) for analyses of grain crude protein. For both means and variances, 95 % confidence intervals were estimated (Figs. 1 and 3). Most of the annual means of the crude protein content are between 11.4 and 12.1 per cent (except pop and sweet corn). Significant deviations were only seldom observed. The annual coefficients of variability are here around 12 %, whereas those of many other characters are around 30 %. For the correlation between crude protein content and thousand grain weight for an average of 13 years (again except pop and sweet corn), a non-significant value of r s =–0.04 was estimated. Furthermore, numerous analysis of variance (Model II) were made, with estimation of the components of variance (also in per cent) for the factors strain and year. They suggest that 3 to 4 ears per strain for every of 3 to 4 years are necessary, in order to ascertain satisfactorily the variability of the crude protein content. Finally, 40 strains of the Gatersleben collection are listed, which gave crude protein means above 12 % for at least four years; the corresponding 95 % confidence intervals are included.
16 (1968–1983) 40 80 . 95 %- (. 1 3). ( %) 11,4 12,1 % ( ). . ( 12 %), 30 %. % 1000 13 (. =–0,04). ( ) () , % 3 4 3–4 . 40 »« , 12 % ( 4-) 95 %- .相似文献
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46.
Bouchard LS Burt SR Anwar MS Kovtunov KV Koptyug IV Pines A 《Science (New York, N.Y.)》2008,319(5862):442-445
Catalysis is vital to industrial chemistry, and the optimization of catalytic reactors attracts considerable resources. It has proven challenging to correlate the active regions in heterogeneous catalyst beds with morphology and to monitor multistep reactions within the bed. We demonstrate techniques, using magnetic resonance imaging and para-hydrogen (p-H2) polarization, that allow direct visualization of gas-phase flow and the density of active catalyst in a packed-bed microreactor, as well as control over the dynamics of the polarized state in space and time to facilitate the study of subsequent reactions. These procedures are suitable for characterizing reactors and reactions in microfluidic devices where low sensitivity of conventional magnetic resonance would otherwise be the limiting factor. 相似文献
47.
Coleman JN Lotya M O'Neill A Bergin SD King PJ Khan U Young K Gaucher A De S Smith RJ Shvets IV Arora SK Stanton G Kim HY Lee K Kim GT Duesberg GS Hallam T Boland JJ Wang JJ Donegan JF Grunlan JC Moriarty G Shmeliov A Nicholls RJ Perkins JM Grieveson EM Theuwissen K McComb DW Nellist PD Nicolosi V 《Science (New York, N.Y.)》2011,331(6017):568-571
If they could be easily exfoliated, layered materials would become a diverse source of two-dimensional crystals whose properties would be useful in applications ranging from electronics to energy storage. We show that layered compounds such as MoS(2), WS(2), MoSe(2), MoTe(2), TaSe(2), NbSe(2), NiTe(2), BN, and Bi(2)Te(3) can be efficiently dispersed in common solvents and can be deposited as individual flakes or formed into films. Electron microscopy strongly suggests that the material is exfoliated into individual layers. By blending this material with suspensions of other nanomaterials or polymer solutions, we can prepare hybrid dispersions or composites, which can be cast into films. We show that WS(2) and MoS(2) effectively reinforce polymers, whereas WS(2)/carbon nanotube hybrid films have high conductivity, leading to promising thermoelectric properties. 相似文献
48.
Salières P Carré B Le Déroff L Grasbon F Paulus GG Walther H Kopold R Becker W Milosević DB Sanpera A Lewenstein M 《Science (New York, N.Y.)》2001,292(5518):902-905
Atoms interacting with intense laser fields can emit electrons and photons of very high energies. An intuitive and quantitative explanation of these highly nonlinear processes can be found in terms of a generalization of classical Newtonian particle trajectories, the so-called quantum orbits. Very few quantum orbits are necessary to reproduce the experimental results. These orbits are clearly identified, thus opening the way for an efficient control as well as previously unknown applications of these processes. 相似文献
49.
Mishchenko MI Geogdzhayev IV Rossow WB Cairns B Carlson BE Lacis AA Liu L Travis LD 《Science (New York, N.Y.)》2007,315(5818):1543
Analysis of the long-term Global Aerosol Climatology Project data set reveals a likely decrease of the global optical thickness of tropospheric aerosols by as much as 0.03 during the period from 1991 to 2005. This recent trend mirrors the concurrent global increase in solar radiation fluxes at Earth's surface and may have contributed to recent changes in surface climate. 相似文献
50.
Terracciano A Abdel-Khalek AM Adám N Adamovová L Ahn CK Ahn HN Alansari BM Alcalay L Allik J Angleitner A Avia MD Ayearst LE Barbaranelli C Beer A Borg-Cunen MA Bratko D Brunner-Sciarra M Budzinski L Camart N Dahourou D De Fruyt F de Lima MP del Pilar GE Diener E Falzon R Fernando K Ficková E Fischer R Flores-Mendoza C Ghayur MA Gülgöz S Hagberg B Halberstadt J Halim MS Hrebícková M Humrichouse J Jensen HH Jocic DD Jónsson FH Khoury B Klinkosz W Knezević G Lauri MA Leibovich N Martin TA 《Science (New York, N.Y.)》2005,310(5745):96-100
Most people hold beliefs about personality characteristics typical of members of their own and others' cultures. These perceptions of national character may be generalizations from personal experience, stereotypes with a "kernel of truth," or inaccurate stereotypes. We obtained national character ratings of 3989 people from 49 cultures and compared them with the average personality scores of culture members assessed by observer ratings and self-reports. National character ratings were reliable but did not converge with assessed traits. Perceptions of national character thus appear to be unfounded stereotypes that may serve the function of maintaining a national identity. 相似文献