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21.
Cosa S Mabinya LV Olaniran AO Okoh OO Bernard K Deyzel S Okoh AI 《Molecules (Basel, Switzerland)》2011,16(3):2431-2442
A bioflocculant-producing marine bacterium previously isolated from marine sediment of Algoa Bay was screened for flocculant production. Comparative analysis of 16S rDNA sequence identified the isolate to have 99% similarity to Virgibacillus sp. XQ-1 and it was deposited in the GenBank as Virgibacillus sp. Rob with accession number HQ537127. The bacterium produced biflocculants optimally in glucose (70.4%) and peptone (70.4%) as sole sources of carbon and nitrogen, alkaline pH (12) (74%); and the presence of Fe2+ (74%). Chemical analysis of the bioflocculant revealed it to be a polysaccharide. 相似文献
22.
Agostino Galanti Dr. Oxana Kotova Dr. Salvador Blasco Chloe J. Johnson Dr. Robert D. Peacock Shaun Mills Prof. John J. Boland Prof. Martin Albrecht Prof. Thorfinnur Gunnlaugsson 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(28):9709-9723
Here we have investigated the influence of the antenna group position on both the formation of chiral amphiphilic EuIII‐based self‐assemblies in CH3CN solution and, on the ability to form monolayers on the surface of quartz substrates using the Langmuir–Blodgett technique, by changing from the 1‐naphthyl ( 2(R) , 2(S) ) to the 2‐naphthyl ( 1(R) , 1(S) ) position. The evaluation of binding constants of the self‐ assemblies in CH3CN solution was achieved using conventional techniques such as UV/Visible and luminescence spectroscopies along with more specific circular dichroism (CD) spectroscopy. The binding constants obtained for EuL , EuL2 and EuL3 species in the case of 2‐naphthyl derivatives were comparable to those obtained for 1‐naphthyl derivatives. The analysis of the changes in the CD spectra of 1(R) and 1(S) upon addition of EuIII not only allowed us to evaluate the values of the binding constants but the resulting recalculated spectra may also be used as fingerprints for assignment of the chiral self‐assembly species formed in solution. The obtained monolayers were predominantly formed from EuL3 (≈85 %) with the minor species present in ≈15 % EuL2 . 相似文献
23.
Dr. Timothy J. Lawton Dr. Joshua R. Uzarski Dr. Shaun F. Filocamo 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(34):12068-12073
The compatibility of multiple functions at a single interface is difficult to achieve, but is even more challenging when the functions directly counteract one another. This study provides insight into the creation of a simultaneously multifunctional surface formed by balancing two orthogonal functions; water repellency and enzyme catalysis. A partially fluorinated thiol is used to impart bulk hydrophobicity on the surface, and an N‐hydroxysuccinimide ester‐terminated thiol provides a specific anchoring sites for the covalent enzyme attachment. Different ratios of the two thiols are mixed together to form amphiphilic self‐assembled monolayers, which are characterized with polarization‐modulation infrared reflection–absorption spectroscopy and contact angle goniometry. The enzyme activity is measured by a fluorescence assay. With the results collected here, specific surface compositions are identified at which the orthogonal functions of water repellency and enzyme catalysis are balanced and exist simultaneously. An understanding of how to effectively balance orthogonal functions at surfaces can be extended to a number of higher‐scale applications. 相似文献
24.
Shaun Bullett 《Communications in Mathematical Physics》1986,107(2):241-262
We investigate invariant circles for a one-parameter family of piecewise linear twist homeomorphisms of the annulus. We show that invariant circles of all types and rotation numbers occur and we classify them into families. We compute parameter ranges in which there are no invariant circles. 相似文献
25.
26.
Wilson SM Wiberg KB Cheeseman JR Frisch MJ Vaccaro PH 《The journal of physical chemistry. A》2005,109(51):11752-11764
Cavity ring-down polarimetry (CRDP) has been exploited to interrogate the nonresonant optical activity (or circular birefringence) of prototypical organic compounds in the vapor phase, thereby revealing the intrinsic chiro-optical response evoked from isolated (solvent-free) molecules. Specific polarization rotation parameters have been measured at two distinct excitation wavelengths (355 nm and 633 nm) for a variety of gas-phase species drawn from the terpene, epoxide, and alkane/alkene families, with complementary solution-phase polarimetric studies serving to highlight the pronounced influence of solute-solvent interactions. Time-dependent linear response calculations performed at high levels of density functional theory have been enlisted to unravel the structural and electronic origins for observed behavior. Aside from elucidating the complex solvation processes that mediate chiro-optical phenomena taking place in condensed media, this study affords a critical assessment for emerging ab initio predictions of nonresonant optical activity and for their promising ability to assist in the determination of absolute molecular stereochemistry. 相似文献
27.
Shaun Stevens 《Annales Scientifiques de l'école Normale Supérieure》2002,35(3):423-435
Let F0 be a non-archimedean local field, of residual characteristic different from 2, and let G be a unitary, symplectic or orthogonal group defined over F0. In this paper, we prove some fundamental results towards the classification of the representations of G via types [8]. In particular, we show that any positive level supercuspidal representation of G contains a semisimple skew stratum, that is, a special character of a certain compact open subgroup of G. The intertwining of such a stratum has been calculated in [19]. 相似文献
28.
29.
D.W. Bullett 《Solid State Communications》1981,38(10):969-972
Calculations of the electronic structure of Cl/Cu(001) are used to discriminate between contending adsorption sites from the electron distribution curves in normal photoemission previously reported. Adsorption above surface Cu atoms is ruled out. Either the four-fold-hollow site or a surface reconstruction would be consistent with the data; preliminary angle-resolved data for off-normal emission favour the four-fold-hollow site. 相似文献
30.
D.W Bullett 《Solid State Communications》1985,55(3):257-260
Densities-of-states calculations are reported for the phosphorus allotrope known as Hittorf's phosphorus, and for two closely related compounds, KP15 and BaP10; all three contain pentagonal tubes of covalently bonded phosphorus atoms. The experimental photoelectron energy distribution curves from amorphous red phosphorus suggest that these tubes could be the dominant structural unit there also. 相似文献