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91.
Nanocrystalline Zn1???x Ag x O y (x?=?10??3???50?×?10??3) thin films evolved through electrodeposition over ITO substrate have been investigated for photoelectrochemical splitting of water. Samples were characterized by XRD, EDX, SEM, AFM, UV–visible optical absorption, and Mössbauer spectral analysis. Ag incorporation led to a decrease in the band gap energy and alterations in microstructural and semiconductor properties. Raising Ag concentration in samples up to 1 % at. caused a significant reduction in density and electrical resistivity, enhanced absorption along with red shift to the band gap energy, anodic shift in flat band potential, and increased charge carrier density, enabling 1 % at. Ag-incorporated ZnO films most photosensitive by yielding highest short-circuit current, photocurrent density, and applied bias photon to current efficiency. Plausible reasons have been offered.  相似文献   
92.
A direct conversion of a thiolacetate to its corresponding sulfonyl chloride in the presence of acid and base sensitive functional groups is described.  相似文献   
93.

Background  

Proteolytic degradation has emerged as a key pathway involved in controlling levels of the Alzheimer's disease (AD)-associated amyloid-β (Aβ) peptide in the brain. The endopeptidase, neprilysin, has been implicated as a major Aβ degrading enzyme in mice and humans. Previous short and intermediate term studies have shown the potential therapeutic application of neprilysin by delivering this enzyme into the brain of APP transgenic mice using gene transfer with viral vectors. However the effects of long-term neprilysin gene transfer on other aspects of Aβ associated pathology have not been explored yet in APP transgenic mice.  相似文献   
94.
Verma BC  Swaminathan K  Sud KC 《Talanta》1977,24(1):49-50
A rapid turbidimetric procedure for the determination of sulphate in soils and plants has been developed with sorbitol as stabilizing agent. When used in a concentration of 20% in the final volume, the sorbitol regulates the size of the BaSO(4) particles formed and stabilizes them against sedimentation, growth and aggregation for long periods of time. The conditions of precipitation are not rigorous, as they are in similar procedures. Linearity of the calibration curve up to 50 ppm of sulphate and good reproducibility are special attributes of the procedure.  相似文献   
95.
96.
Detailed features of extremely collimated nuclear interactions induced by cosmic ray particles in carbon and brass (belonging to group I as classified in Part I of this series of papers) are presented. These extremely collimated nuclear interactions seem to be preferentially induced by pions rather than by nucleons; also the relative frequency of these seems to be less when brass is used as target compared to the case with carbon as target. The distribution of multiplicities of secondary particles emitted in the forward direction show certain regularities in the case of interactions induced by charged primaries. Observations on the γ-rays associated with these events give support to the interpretation that in these inelastic collisions pions are produced in pairs in the forward direction with low transverse momentum. It is suggested that such a low energy di-pion system could be the same as found in the so-called ABC effect.  相似文献   
97.
Verma KK 《Talanta》1975,22(10-11):920-921
Thiols are titrated in acetone or dimethylformamide with sodium methoxide, employing visual end-point detection with Thymol Blue, Victoria Blue, p-hydroxyazobenzene or Azo Violet. Aromatic thiols are titrated in the presence of aliphatic thiols in acetone, with Thymol Blue as indicator.  相似文献   
98.
99.
A novel bis scaffold containing a pentapeptide PHGGG, derived from the prion octarepeat, forms fibrils of nanometric dimensions, thus indicating that certain segments in the unstructured region of the prion protein may facilitate an initial fibrillation event.  相似文献   
100.
We demonstrate how tracer microrheology methods can be extended to study submicron scale variations in the viscoelastic response of soft materials; in particular, a semidilute solution of lambda-DNA. The polymer concentration is depleted near the surfaces of the tracer particles, within a distance comparable to the polymer correlation length. The rheology of this microscopic layer alters the tracers' motion and can be precisely quantified using one- and two-point microrheology. Interestingly, we found this mechanically distinct layer to be twice as thick as the layer of depleted concentration, likely due to solvent drainage through the locally perturbed polymer structure.  相似文献   
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