Two Analogues of Chloramphenicol

The preparation of D, L- threo-1-[p-(p\u27-nitrophenoxy)-phenyl]-2-dichloroacetamido-1,3-propanediol and D, L-threo-1-[p -(o\u27 - nitrophenoxy)-phenyl]-2-dichloroacetamido-1,3-propanediol is described. Compared with chloramphenicol these compounds showed no interesting activity in antibacterial tests

Two Analogues of Chloramphenicol

The preparation of D, L- threo-1-[p-(p\u27-nitrophenoxy)-phenyl]-2-dichloroacetamido-1,3-propanediol and D, L-threo-1-[p -(o\u27 - nitrophenoxy)-phenyl]-2-dichloroacetamido-1,3-propanediol is described. Compared with chloramphenicol these compounds showed no interesting activity in antibacterial tests

Absolute Configuration of β-Hydroxy-β-phenylpropionic acid*

(+)-Methyl β-methoxy-β-phenylpropionate (VIII) was prepared from (+)-mandelic acid and from (+)-β-hydroxy-β-phenylpropionic acid (I). In this way the configuration of I was correlated with that of mandelic acid

Absolute Configuration of β-Hydroxy-β-phenylpropionic acid*

(+)-Methyl β-methoxy-β-phenylpropionate (VIII) was prepared from (+)-mandelic acid and from (+)-β-hydroxy-β-phenylpropionic acid (I). In this way the configuration of I was correlated with that of mandelic acid

Thiosemicarbazones and 2-Thio-4-(phthalimidoalkylidene) thiazolid-5-ones of N-Phthaloyl Amino Aldehydes. Preparation and Antibacterial Activity

Thiosemicarbazones of the formula I and 2-thio-4-(phthalimidoalkylidene) thiazolid-5-ones of the formula II derived from glycine, L-alanine; B-alanine, DL-leucine, DL-valine, L-tyrosine, DL-serine and a-amino-n-butyric acid were prepared and tested against Staphylococcus aureus, B. pyocyaneus, E. coli and Enterococcus

Thiosemicarbazones and 2-Thio-4-(phthalimidoalkylidene) thiazolid-5-ones of N-Phthaloyl Amino Aldehydes. Preparation and Antibacterial Activity

Thiosemicarbazones of the formula I and 2-thio-4-(phthalimidoalkylidene) thiazolid-5-ones of the formula II derived from glycine, L-alanine; B-alanine, DL-leucine, DL-valine, L-tyrosine, DL-serine and a-amino-n-butyric acid were prepared and tested against Staphylococcus aureus, B. pyocyaneus, E. coli and Enterococcus

Solid Freeform Fabrication of Transparent Fused Quartz using a Filament Fed Process

Glass is a critical material for many scientific and engineering applications including optics, communications, electronics, and hermetic seals. Despite this technological relevance, there has been minimal research toward Additive Manufacturing (AM) of glass, particularly optically transparent glass. Additive Manufacturing of transparent glass offers potential advantages for lower processing costs for small production volumes, increased design freedom, and the ability to locally vary the optical properties of the part. Compared to common soda lime glass, fused quartz is better for AM since it has lower thermal expansion and higher index homogeneity. This paper presents a study of additive manufacturing of transparent fused quartz by a filament fed process. A CW CO2 laser (10.6 µm) is used to melt glass filaments layer by layer. The laser couples to phononic modes in the glass and is well absorbed. The beam and melt pool are stationary while the work piece is scanned using a standard lab motion system. Representative parts are built to explore the effects of variable laser power on the properties of printed fused quartz. During printing the incandescent emission from the melt pool is measured using a spectrometer. This permits process monitoring and identifies potential chemical changes in the glass during printing. After deposition, the printed parts are polished and the transmission measured to calculate the absorption/scattering coefficient. Finally, a low-order thermal analysis is presented and correlated to experimental results, including an energy balance and finite volume analysis using Fluent. These results suggest that optical quality fused quartz parts with low absorption and high index of refraction uniformity may be printed using the filament-fed process

Nonlinearities and Carrier Dynamics in Refractory Plasmonic TiN Thin Films

Titanium nitride is widely used in plasmonic applications, due to its robustness and optical properties which resemble those of gold. Despite this interest, the nonlinear properties have only recently begun to be investigated. In this work, beam deflection and non-degenerate femtosecond pump-probe spectroscopy (800 nm pump and 650 nm probe) were used to measure the real and imaginary transient nonlinear response of 30-nm-thick TiN films on sapphire and fused silica in the metallic region governed by Fermi-smearing nonlinearities. In contrast to other metals, it is found that TiN exhibits non-instantaneous positive refraction and reverse saturable absorption whose relaxation is dominated by slow thermal diffusion into the substrate lasting several hundred picoseconds. Ultrafast contributions arising from hot-electron excitations are found to be a small part of the overall response, only appearing significant in the TiN on fused silica at irradiance levels above 100 GW-cm-2. The modeling and origin of this response is discussed, and TiN is found to be adept at achieving ultrafast (below 1 ps) lattice heating which, combined with the robustness and low-cost of the material may prove useful in various thermo-optical applications such as local heating, heat-assisted processes, and nanoscale heat transfer

Two problems related to prescribed curvature measures

Existence of convex body with prescribed generalized curvature measures is discussed, this result is obtained by making use of Guan-Li-Li's innovative techniques. In surprise, that methods has also brought us to promote Ivochkina's $C^2$ estimates for prescribed curvature equation in \cite{I1, I}.Comment: 12 pages, Corrected typo

Accessible reasoning with diagrams: From cognition to automation

High-tech systems are ubiquitous and often safety and se- curity critical: reasoning about their correctness is paramount. Thus, precise modelling and formal reasoning are necessary in order to convey knowledge unambiguously and accurately. Whilst mathematical mod- elling adds great rigour, it is opaque to many stakeholders which leads to errors in data handling, delays in product release, for example. This is a major motivation for the development of diagrammatic approaches to formalisation and reasoning about models of knowledge. In this paper, we present an interactive theorem prover, called iCon, for a highly expressive diagrammatic logic that is capable of modelling OWL 2 ontologies and, thus, has practical relevance. Significantly, this work is the first to design diagrammatic inference rules using insights into what humans find accessible. Specifically, we conducted an experiment about relative cognitive benefits of primitive (small step) and derived (big step) inferences, and use the results to guide the implementation of inference rules in iCon