Structural assessment of a space station solar dynamic heat receiver thermal energy storage canister

The structural performance of a space station thermal energy storage (TES) canister subject to orbital solar flux variation and engine cold start up operating conditions was assessed. The impact of working fluid temperature and salt-void distribution on the canister structure are assessed. Both analytical and experimental studies were conducted to determine the temperature distribution of the canister. Subsequent finite element structural analyses of the canister were performed using both analytically and experimentally obtained temperatures. The Arrhenius creep law was incorporated into the procedure, using secondary creep data for the canister material, Haynes 188 alloy. The predicted cyclic creep strain accumulations at the hot spot were used to assess the structural performance of the canister. In addition, the structural performance of the canister based on the analytically determined temperature was compared with that based on the experimentally measured temperature data

The surface accessibility of α-bungarotoxin monitored by a novel paramagnetic probe

The surface accessibility of {alpha}-bungarotoxin has been investigated by using Gd2L7, a newly designed paramagnetic NMR probe. Signal attenuations induced by Gd2L7 on {alpha}-bungarotoxin C{alpha}H peaks of 1H-13C HSQC spectra have been analyzed and compared with the ones previously obtained in the presence of GdDTPA-BMA. In spite of the different molecular size and shape, for the two probes a common pathway of approach to the {alpha}-bungarotoxin surface can be observed with an equally enhanced access of both GdDTPA-BMA and Gd2L7 towards the protein surface side where the binding site is located. Molecular dynamics simulations suggest that protein backbone flexibility and surface hydration contribute to the observed preferential approach of both gadolinium complexes specifically to the part of the {alpha}-bungarotoxin surface which is involved in the interaction with its physiological target, the nicotinic acetylcholine receptor

Imaging Polarimeter Arrays for Near-Millimeter Waves

An integrated-circuit antenna array has been developed that images both polarization and intensity. The array consists of a row of antennas that lean alternately left and right, creating two interlaced sub-arrays that respond to different polarizations. The arrays and the bismuth bolometer detectors are made by a photoresist shadowing technique that requires only one photolithographic mask. The array has measured polarization at a wavelength of 800 µm with an absolute accuracy of 0.8° and a relative precision of 7 arc min. and has demonstrated nearly diffraction-Iimited resolutiort of a 20° step in polarization

Comparison of chemical profiles and effectiveness between Erxian decoction and mixtures of decoctions of its individual herbs : a novel approach for identification of the standard chemicals

Acknowledgements This study was partially supported by grants from the Seed Funding Programme for Basic Research (Project Number 201211159146 and 201411159213), the University of Hong Kong. We thank Mr Keith Wong and Ms Cindy Lee for their technical assistances.Peer reviewedPublisher PD

Antimicrobial Activity of Phomopsis SP. ED2, an Endophytic Fungus Isolated From Orthosiphon Stamineus Benth

This study aimed to investigate the antimicrobial activity of the endophytic fungus Phomopsis sp. ED2, which was previously isolated from the flower of the medicinal plant Orthosiphon stamineus Benth, in Penang, Malaysia. The 14 days-old fungal cultures were extracted with different organic solvents, include hexane, dichloromethane, ethyl acetate and butanol. The antimicrobial activities of the extracts were tested by disc diffusion assay. Based on the results, most antimicrobial compounds were present in the ethyl acetate fraction, and this extract could significantly inhibit the activity of bacteria, yeasts and fungi. The results also indicate that the antimicrobial compounds were mainly associated with the fungal biomass and all the Gram-positive test bacteria were inhibited by the ethyl acetate extract of the fungal biomass. Notably, methicillin-resistant Staphylococcus aereus exhibited a high sensitivity to the extract, with a low minimal inhibitory concentration and low minimal lethal concentration. The isolate also effectively inhibited the growth of the dermatophytes Microsporum gypseum and Trichophyton rubrum. Preliminary phytochemical screening also demonstrated that the extract contains phenols and steroids which possess antimicrobial activity. These results reveal that the endophytic fungus Phomopsis sp. is potential source of novel chemotherapeutic agent

Anti-MRSA Activity of Penicillium Minioluteum ED24, an Endophytic Fungus Isolated From Orthosiphon Stamineus Benth

Nowadays, the medical concerns with Methicillin-resistant Staphylococcus aereus (MRSA) arised when in 2009, the proportion of S. aureus isolates that are resistant to methicilin has increased to 59.5%- 64.4% in South East Asia. Hence a new antibacterial agent from natural source is necessary to combat the infectious diseases. This study aimed to investigate the anti-MRSA activity of the endophytic fungus Penicillium minioluteum ED24, which was previously isolated from the leaf of the medicinal plant Orthosiphon stamineus Benth, in Penang, Malaysia. Methanol was used to extract the freeze-dried fungal biomass of the 14-days old fungal culture. The extract showed very significant anti-MRSA activity of disc diffusion assay with the minimal inhibitory concentration of 31.3 mg/mL and minimal lethality concentration of 250 mg/mL. Besides, 50% growth reduction of MRSA was observed at 33.2 h at the concentration of extract at MIC and 26.7 h at concentration of 2MIC. The structural degeneration of MRSA was observed by using scanning electron microscope (SEM). The SEM micrographs showed that the formation of cavities were observe on the extract treated cells and the cell wall structure of the MRSA was collapsed after treated with the fungal extract. The results suggesting that the bacterial cell wall is the target of the antibiotic compound(s) present in the extract. These results reveal that the endophytic fungus P. minioluteum ED24 a is potential source of anti-MRSA compound

Relation between concurrence and Berry phase of an entangled state of two spin 1/2 particles

We have studied here the influence of the Berry phase generated due to a cyclic evolution of an entangled state of two spin 1/2 particles. It is shown that the measure of formation of entanglement is related to the cyclic geometric phase of the individual spins. \\Comment: 6 pages. Accepted in Europhys. Letters (likely to be published in vol 73, pp1-6 (2006)

Optical Evaluation on Delamination Buckling of Composite Laminate with Impact Damage

The delamination buckling and growth behaviors of a cross-ply composite laminate with damage induced by low velocity impact are investigated optically using three-dimensional digital image correlation (3D-DIC) method. For the 3D deformation measurement, the 3D-DIC setup comprised of two CCD cameras was adopted. The rectangle specimen was impacted under the impact energy of 7.0 J using a drop-weight testing machine, and the impact damage was detected by means of X-ray nondestructive evaluation (NDE) technique. The 3D deformation field measured with the optical system clearly reveals that the delamination buckling characteristic of the specimen mainly appears local deformation mode under compression after impact test. Moreover, the behavior of delamination growth evaluated by the 3D-DIC optical method reasonably agrees with the NDE observed damage result after compression

On the design of reliable hybrid wired-wireless network-on-chip architectures

With the ever increase in transistor density over technology scaling, energy and performance aware hybrid wire- less Network-on-Chip (WiNoC) has emerged as an alternative solution to the slow conventional wireline NoC design for future System-on-Chip (SoC). However, combining wireless and wireline channels drastically reduces the total reliability of the commu- nication fabric. Besides being lossy, existing feasible wireless solution for WiNoCs, which is in the form of millimeter wave (mm-Wave), relies on free space signal radiation which has high power dissipation with high degradation rate in the signal strength per transmission distance. Alternatively, low power wireless communication fabric in the form of surface wave has been proposed for on-chip communication. With the right design considerations, the reliability and performance benefits of the surface wave channel could be extended. In this paper, we propose a surface wave communication fabric for emerging WiNoCs that is able to match the channel reliability of traditional wireline NoCs. Here, a carefully designed transducer and commercially available thin metal conductor coated with a low cost dielectric material are employed to general surface wave signal to improve the wireless signal transmission gain. Our experimental results demonstrate that, the proposed communication fabric can achieve a 5dB operational bandwidth of about 60GHz around the center frequency (60GHz). By improving the transmission reliability of wireless layer, the proposed communication fabric can improve maximum sustainable load of NoCs by an average of 20.9% and 133.3% compared to existing WiNoCs and wireline NoCs, respectively