Metallothionein Genes in the Nematode Caenorhabditis elegans and Metal Inducibility in Mammalian Culture Cells

Genomic DNAs of metallothionein Ⅰ and Ⅱ in Caenorhabditis elegans (CeMT-Ⅰand CeMT-Ⅱ) were isolated by YAC library/polytene filter hybridization followed by subcloning of corresponding cosmid clones. Both genes are mapped at chromosome V. Although the similarities of 5'-flanking regions and coding regions have shown only 55-58%, the introns are split at the same position in both genes, indicating that these two genes are originally from the same gene. While several metal responsive elements are conserved among eukaryotes, only one metal responsive element was found in the promoter region in CeMT-Ⅱ and not in CeMT-Ⅰ. Indced, neither of 5'-flanking regions of CeMT-Ⅰ nor CeMT-Ⅱ connected to chloramphenicol acetyltransferase reporter gene is responsive to heavy metals in mammalian culture cells by transient transfection analysis. These results would suggest that the metal regulatory factors in C.elegans might be different from those conserved in invertebrates and vertebrates, although the MTs in C elegans revealed the similarities to mammalian MTs in several points

Metal Induced Inhibition of Photosynthesis,Photosynthetic Electron Transport Chain and ATP Content of Anabaena doliolum and Chlorella vulgaris:Interaction with Exogenous ATP

This study demonstrates a concentration dependent inhibition of carbon fixation, O2 evolution, photosynthetic electron transport chain and ATP content of A. doliolum and C. vulgaris by Cu, Ni and Fe. Although the mode of inhibition of photosynthetic electron transport chain of both the algae was similar, PS II depicted greater sensitivity to the test metals used. The toxicity in both organisms was Cu > Ni > Fe. A. doliolum was, however, more sensitive to Cu and Ni, and C. vulgaris to Fe. Toxicity was generally dependent on metal uptake, which in turn was dependent on their concentrations in the external medium. A partial restoration of nutrient uptake, carbon fixation, and enzyme activities following supplementation of exogenous ATP suggests that ATP regulates toxicity through chelation.

Solution-based metal induced crystallization of a-Si

This paper investigates a simplified metal induced crystallization （MIC） of a-Si, named solution-based MIC （SMIC）. The nickel inducing source was formed on a-Si from salt solution dissolved in de-ionized water or ethanol, a-Si thin film was deposited with low pressure chemical vapour deposition or plasma enhanced chemical vapour deposition as precursor material for MIC. It finds that the content of nickel source formed on a-Si can be controlled by solution concentration and dipping time. The dependence of crystallization rate of a-Si on annealing time illustrated that the linear density of nickel source was another critical factor that affects the crystallization of a-Si, besides the diffusion of nickel disilicide. The highest electron Hall mobility of thus prepared S-MIC poly-Si is 45.6 cm^2/（V· s）. By using this S-MIC poly-Si, thin film transistors and display scan drivers were made, and their characteristics are presented.

Ar（12+）Induced Irradiation Damage in Bulk Metallic Glass(Cu47Zr45Al8)98.5Y1.5

The highly charged ion Ar^12＋ with an energy of 3 Me V is used for irradiating metallic glass （Cu47Zr45Al8）98.5Y1.5 and polycrystalline metallic W at the irradiation fluences of 1× 10^14 ions/cm2, 1 × 10^15 ions/cm^2 and 1 × 10^16 ions/cm^2. The main structure of metallic glass remains an amorphous phase under different irradiation fluences according to x-ray diffraction analysis. The scanning electron microscope observation on the morphologies indicates that no significant irradiation damage occurs on the surface and cross section of the metallic glass sample after different fluences of irradiation, while a large area of irregular cracks and holes were observed on the surface of metallic W at a fluence of 1 ×10^16 ions/cm^2, with cracks and channel impairments at a certain depth from the surface. The root-mean-square （rms） roughness of metallic glass increases with increasing fluence of Ar^12＋, while the reflectance decreases with increasing irradiation fluence. A nano-hardness test shows that the hardness of metallic glass decreases after irradiation. Under certain a higher capability of resistance to Ar^12＋ irradiation in conditions, metallic glass （Cu47 Zr45Al8 ）98.5 Y1.5 exhibits comparison with polycrystalline W.

Electric Field Induced Permanent Superconductivity in Layered Metal Nitride Chlorides HfNCl and ZrNCl

Devices of electric double-layer transistors （EDLTs） with ionic liquid have been employed as an effective way to dope carriers over a wide range. However, the induced electronic states can hardly survive in the materials after releasing the gate voltage VG at temperatures higher than the melting point of the selected ionic liquid. Here we show that a permanent superconductivity with transition temperature Tc of 24 and 15K is realized hi single crystals and polycrystalline samples of HfNCI and ZrNCI upon applying proper VG＇s at different temperatures. Reversible change between insulating and superconducting states can be obtained by applying positive and negative VG at low temperature such as 220K, whereas VG ＇s applied at 250K induce the irreversible superconducting transition. The upper critical field He2 of the superconducting states obtained at different gating temperatures shows similar temperature dependence. We propose a reasonable scenario that partial vacancy of Cl ions could be caused by applying proper VG＇s at slightly higher processing temperatures, which consequently results in a permanent electron doping in the system. Such a technique shows great potential to systematically tune the bulk electronic state in the similar two-dimensional systems.

Splitting Phenomenon Induced by Magnetic Field in Metallic Carbon Nanotubes

In the framework of the tight-binding model, the excitons states and linear absorption spectra are calculated in the metallic single-walled carbon nanotubes, with the axial magnetic field applied. From our calculations, it is found that for the Mll and M22 transitions, the exeiton states are split into four separate column states by the applied magnetic field due to the symmetry breaking. More interesting is that the splitting can be directly reflected from the linear absorption spectra~ which are dominated by four main absorption peaks. In addition, the splitting with increasing the axial magnetic field is also calculated, which increases linearly with the applied magnetic field. The obtained results are expected to be detected by the future experiments.

Optimizing Structure and Processes of Nickel Induced Lateral Crystallization

The structure and processes of nickel induced lateral crystallization are studied.The structure of metal induced lateral crystallization(MILC) is improved by opening a seed window on the buried oxide,which is helpfu to get superior quality of large grain poly Si at low temperature.By optimizing the temperature and time of annealing based on others' pervious work,the large grain poly Si with few defects are obtained,and the typical grain size is 70～80μm.The methods of etching NiSi 2 which is created after the long time annealing are also studied for the first time.Finally,a method is successfully chosen to reduce the possible contamination of Ni and to guarantee the MILC for the submicron VLSI application.

Dynamic Ni gettered by PSG from S-MIC poly-Si and its TFTs

A dynamic phosphor-silicate glass （PSG） gettering method is proposed in which the processes of the gettering of Ni by PSC and the crystallizing of α-Si into poly-Si by Ni take place simultaneously. The effects of PSC gettering process on the performances of solution-based metal induced crystallized （S-MIC） poly-Si materials and their thin film transistors （TFTs） are discussed. The crystallization rate is much reduced due to the fact that the Ni as a medium source of crystallization is extracted by the PSC during crystallization at the same time. The boundary between two neighbouring grains in S-MIC poly-Si with PSG looks blurrier than without PSG. Compared with the TFTs made from S-MIC poly-Si without PSC gettering, the TFTs made with PSC gettering has a reduced gate induced leakage current.

Effect of metal surface morphology on nano-structured patterns induced by a femtosecond laser pulse and its experimental verification

The effect of material surface morphology on the periodic subwavelength of nano-structures induced by a femtosecond（fs） laser was investigated systematically from the initial surface roughness, the different scratches, the pre-formed ripples, and the ＂layer-carving＂ technology experiments. The results of the comparative experiments indicate that the initial surface conditions of the target surface have no obvious effects on the spatial structured periods（SSPs） and the ripple orientation of the periodic nano-structures induced by a fs laser, which agreed well with the foretold present surface two-plasmon resonance（STPR） model. Furthermore, different shapes of nanogrids with high regularity and uniformity were obtained by fs-laser fabrication.