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71.
Anna De Simone 《Proceedings of the American Mathematical Society》1998,126(10):2919-2926
We provide some conditions which are equivalent to the uniqueness of Hewitt-Yosida-type decomposition and Lebesgue-type decomposition for real valued additive functions defined on orthomodular posets.
72.
Overview: The Potential of silanes for chromate replacement in metal finishing industries 总被引:3,自引:0,他引:3
Wim J. van Ooij Danqing Zhu Vignesh Palanivel J. Anna Lamar Matthew Stacy 《Silicon Chemistry》2006,3(1-2):11-30
Trialkoxysilanes (or silanes) have emerged as a very promising alternative for chromates in metal finishing industries. Compared to the conventional chromating processes, the major merits of silane-based surface treatments include: eco-compliance, easy-control processing, comparable corrosion protection of metals as well as paint adhesion to a variety of topcoats. In this overview paper, we report the recent status of silane studies including results of corrosion performance tests, the mechanism of corrosion protection of metals by silanes and the themal stabilities of silane films. We also address the new fields that we are beginning to explore such as nano-structured silane films, “self-healing” silane films, and “super-primers”. 相似文献
73.
Let X be a complex connected projective nonsingular algebraic surface endowed with an ample line bundle L, which is spanned by its global sections. Pairs (X, L) as above, with sectional genus g(X, L)=1+(L·(K
X
L))/2=3 are classified by means of the main techniques of adjunction theory. 相似文献
74.
Giampiero Bettinetti Milena Sorrenti Laura Catenacci Franca Ferrari Silvia Rossi Ilaria Salvadeo Paolo Carraro 《Journal of inclusion phenomena and macrocyclic chemistry》2007,57(1-4):329-332
Triacetyl α-cyclodextrin, triacetyl β-cyclodextrin and triacetyl γ-cyclodextrin were tested as possible hydrophobic carriers
to prolong the release of hydrophilic teicoplanin (TCP). Physical–chemical characterization of individual components, drug-carrier
physical mixtures at 0.5, 0.67 and 0.75 mass fraction of carrier, and the respective interaction products by kneading or evaporative
crystallization under microwave irradiation was carried out using differential scanning calorimetry (DSC) and thermogravimetric
analysis (TGA). In vitro drug release in pH 7.4 phosphate buffer at 37 °C was determined by intrinsic dissolution rate (IDR)
measurements on non disintegrating compressed discs. Solid-state interactions of TCP with triacetyl α-cyclodextrin by evaporative
crystallization and kneading and with triacetyl β-cyclodextrin by evaporative crystallization (probably resulting in carrier
amorphization) were demonstrated. The role of carrier hydrophobicity, carrier mass fraction and preparation method of solid
drug-carrier combinations on solid-state drug-carrier interactions and slowing down of TCP release was assessed. Modulation
of drug release can be achieved using TCP-triacetyl γ-cyclodextrin combinations at 0.5 mass fraction of carrier. 相似文献
75.
Lichens have long been regarded as bioindicators of air pollution, and structural studies typically have indicated negative impacts in highly polluted areas. In this research, Parmelia sulcata and Platismatia glauca were collected from one clean and two polluted sites in the Pacific Northwest forests of the United States to investigate the anatomical and ultrastructural responses of relatively resistant lichens to moderate air pollution. Light microscopy of polluted materials revealed only slight increases in the algal cell proportions of the thallus, and a decrease in the fungal cells of the medulla. Using transmission electron microscopy, increased lipid droplets in the cytoplasm and an increase in the cell wall thickness of the photobionts were found in the polluted lichens. These results were compared with physiological data in which the net carbon uptake did not show any significant differences; however, the total chlorophyll content was heightened in the polluted samples. The increased total chlorophyll content and the absence of any changes in the algal cell proportions of the polluted samples suggest that the photobionts possessed a higher chlorophyll content per unit volume of the photobiont at polluted sites. The results also indicate that lichens have altered their storage allocation in different cellular compartments. This may be a result of symbiotic readjustment(s) between the photobiont and the mycobiont. In comparison with the physiological results from these two species, these changes do not represent damaging effects by low-level air pollution. 相似文献
76.
Anna Rizzolo Patrizia Lombardi Maristella Vanoli Stefano Polesello 《Journal of separation science》1995,18(5):309-314
Capillary GC/sensory analysis was used to judge if dynamic headspace on sliced pulp and on intact fruit, and solvent extraction could collect the “character impact” and the “contributory” aroma compounds in peaches. Capillary GC/sensory data showed that the headspace techniques selectively recovered the “contributory” volatile compounds, which are strictly related to the characteristic odor of the various peach cultivars, whereas solvent extraction better quantified the “character impact” compounds (lactones). 相似文献
77.
A study of the viability of three derivatizing reagents for obtaining amino acid profiles in honey through high performance liquid chromatography (HPLC) is presented. A method using diode array detection based on a reaction with diethyl ethoxymethylene malonate (DEMM) and two other methods using fluorescence detection based on derivatization with fluorenylmethyl chloroformate (FMOC-Cl) and 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate (AQC) have been developed. The three methods yield detection limits close to the ppb level, but vary in relation to other analytical characteristics. The use of methyl chloroformate derivatives allows the profile to be obtained with the greatest sensitivity within a short time frame. On applying such methods to honey samples of diverse botanical origin, we observe that the proline values obtained are always lower than those found using the official spectrophotometric method, thereby underlining the advisability of using HPLC methods to reduce uncertainty in these results. 相似文献
78.
79.
JPC – Journal of Planar Chromatography – Modern TLC - The thin-layer chromatographic behavior of three of the newest oral antidiabetic agents, pioglitazone, rosiglitazone, and... 相似文献
80.
De Salvo G Gattuso G Notti A Parisi MF Pappalardo S 《The Journal of organic chemistry》2002,67(3):684-692
A series of tri-O-substituted 1,3-bridged calix[5]arene crown-6 ethers bearing alkyl, arylalkyl, alkoxyalkyl, and alkoxycarbonylmethyl residues at the lower rim and either (t)()Bu or H substituents at the upper rim have been synthesized. (1)H NMR studies have shown that p-tert-butylcalix[5]crowns, irrespective of the size and nature of their lower rim pendant groups, adopt preorganized conelike conformations, whereas p-H-calix[5]crowns with bulky substituents preferentially exist in solution as partial cone conformers (C(1) symmetry). Calix[5]crown derivatives behave as mono- or ditopic receptors for isomeric butylammonium ions, forming endo-cavity (inside the calixarene cup) and/or exo-cavity (at the crown ether moiety) 1:1 complexes according to the shape of the guest. These two binding modes can be clearly distinguished and monitored by (1)H NMR titration experiments. 相似文献