Translational relaxation and electronic quenching processes of translationally hot O(1D) atoms by collisions with N2 in a gas cell at room temperature are studied using a vacuum ultraviolet laser induced fluorescence technique. The initial hot O(1D) atoms which have translational energies of 18.2 and 9.8 kcal mol−1 are produced by the photodissociation of N2O at 193 nm and O2 at 157 nm, respectively. The translational relaxation processes are investigated by time resolved measurements of the Doppler profiles for the O(1D) atoms, while the quenching processes are studied by measuring both the decrease of the O(1D) concentration and the increase of the product O(3P) concentration after the photochemical formation of the hot O(1D) atoms. When the initial translational energy of O(1D) is 9.8 kcal mol−1, about 40% of the O(1D) atoms are electronically quenched before the entire thermalization of the hot O(1D) atoms takes place in a gaseous mixture with N2. This indicates that the translational relaxation rate of O(1D) by collisions with N2 is not fast enough compared with the electronic quenching by N2. It is found that the steady state distribution of the O(1D) translational energy in the upper stratosphere is superthermal and that the populations at high translational energies are higher than that estimated from an equilibrated condition with the ambient air. The cross section of the electronic quenching by N2 at the high collision energy of (8±6) kcal mol−1 is found to be (0.7±0.1) Å2, which is about 5 times smaller than that at thermal collision energy at 298 K.

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This work is carried out with Gardenia coronaria leaves that belong to the family Rubiaceae, which is a small-to-medium-sized but tall, deciduous tree, 7.6–9 m high on an average. Leaves are used for the treatment of rheumatic pain and bronchitis. The leaf of the plant consists of coronalolide, coronalolic acid, coronalolide methyl ester, ethyl coronalolate acetate triterpenes (secocycloartanes), and so forth. Methanol extract from the leaves of Gardenia coronaria was completely screened for membrane stability and antibacterial activity. The lower concentrations of Methanolic leaf extract of Gardenia coronaria gave good antimicrobial and anti-inflammatory activity, but higher concentrations gave relatively more projecting antibacterial activity in vitro as compared with Kanamycin. The crude drug's anti-inflammatory effects were compared with those of Aspirin as positive control. The Methanolic extracts of Gardenia coronaria leaves possessed a broad spectrum antibacterial activity against a variety of both Gram-negative and Gram-positive organisms like Streptococcus agalactiae, Escherichia coli, Pseudomonas aeruginosa, Bacillus cereus, Shigella sonnei, Shigella boydii, and Proteus mirabilis, with a zone of inhibition from 10 to 16 mm. The extract also showed good membrane stability to be considered as having significant anti-inflammatory action.

Copper oxide nanoparticles (CuO-NPs) were synthesized via chemical precipitation method using copper (II) chloride dihydrate and sodium hydroxide. Then nanoparticles were characterized by using X-ray Diffraction (XRD), Scanning Electron Microscope (SEM), Energy Dispersive X-ray (EDX), and Fourier Transform Infra Red (FTIR) spectroscopy. The XRD patterns and EDX spectra showed that the prepared CuO-NPs were highly pure, crystalline and nano-sized. The SEM image suggested that nano particles were spherical and there was a tendency of agglomerations. The nanoparticles showed interactions between copper and oxygen atoms supported by FTIR studies.

The present investigations were undertaken to find out whether and how often cycling, processing and programming can be repeated, whether repeated programming affects the one way effect and how much irreversible strain the shape memory polymeric material accumulates at a particular temperature. The effect was investigated in dependence of different stress levels, and the effect of both recovery temperature and recovery time was considered. As a model material the commercially and industrially applicable amorphous shape memory polymer Tecoflex® was examined and subjected to 50 programming cycles. Tecoflex® is characterized by a glass transition temperature, Tg, of 74 °C, above which it looses all its strength. During tensile testing at 20 °C (T < Tg), stresses a steady increase to 26 MPa as strains approached the rupture strain of 25%. It is observed that at 60 °C (T < Tg, but near Tg) the material can be strained to more than 2500% before rupture occurs while stresses slowly increase to values less than 0.3 MPa. It turns out that programming, cooling, unloading and heating to trigger the one way effect causes an increase of irreversible strain that is associated with a corresponding decrease of the intensity of the one way effect during the first thermomechanical cycles.