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Selective epitaxial embedded SiGe(B) (e-SiGe) is widely used for Source/Drain in advanced CMOS technologies for introducing compressive strain to the PMOS channel which improves the hole mobility. In this paper, we investigated SiGeB epitaxy on different substrates including SiGe, Si:B, SiGeB and also dielectric films including ALD/ CVD SiN, thermal/CVD SiO2. For SiGeB epitaxy on crystallized film substrates, results show that Germanium would prevent Boron inter-diffusion between the substrate and the following deposited SiGeB. Growth Rate (GR) of the epitaxy e-SiGe film is also investigated. A combination of the SiGeB film concentration and GR study shows that Boron concentration and strain introduced by lattice mismatch between the substrate and the epitaxial film are two competitive factors to the GR. The film grows faster when Boron concentration is higher while larger strain would degrade the GR. Selectivity study shows that CVD SiN film have the best selectivity. We also investigated the film selectivity before and after thermal anneal. Results show that film selectivity become worse after thermal anneal.

Compressive stress introduced by source/drain (S/D) SiGe is widely used in 45nm node and beyond advanced technology which boost the P-channel hole mobility. Quantitive measurement of localized stress in channel is limited by the scaling shrinking. Transmitted electron microscopy- Nano Beam Diffraction (TEM-NBD) is an effective method for the local stress distribution measurement in channel and well area derived from S/D Si1-xGex. In this paper, we study the channel strain from the following aspect, including i) active area (AA) width, ii) S/D recess shape, iii) S/D recess trench depth, and iv) Germanium (Ge), Boron (B) concentration of S/D Si1-xGex and Ge, B distribution profile. It is revealed that strain has strong relation with these factors. Pitch with narrow AA width shows lower strain than that of wider AA width. S/D recess shape affects the proximity which is critical for the stress derived from S/D SiGe transmit to channel location. Moreover, S/D recess trench depth determines the volume of filled SiGe then affect the strain to channel. Both of the Ge, B concentration of S/D SiGe and the distribution profile directly affects the lattice mismatch which results in the strain. In general, all these factors affect the volume of the filled SiGe and Ge concentration which eventually determine the strain of S/D to channel area.

Slower cooling and solidification rates tend to increase both the grain size and dendrite arm spacings (DAS) of conventional castings. Both grain size and DAS impact strength and ductility, and so heavy section castings generally have inferior mechanical properties than thin-walled castings. However, the primary phase of semi-solid castings is not produced during solidification in the mold, but instead is developed in the feed material. Therefore, the size of the primary phase is essentially independent of the solidification rate, and so the mechanical properties of semi-solid castings should be less sensitive to the wall thickness of the casting. This paper describes the results of a study to examine the impact of wall thickness on the microstructure, hardness and mechanical properties of semi-solid castings. Castings were produced at three thicknesses — 7.5 mm, 15 mm and 50 mm. Results are compared to literature data for conventional fully-liquid castings produced at similar section thicknesses.

Silanized magnetic particles have been developed by means of a number of different methods for coupling antibodies for use in radioimmunoassay (RIA) and immunoradiometric assay (IRMA) of thyroid related hormones. Carbodiimide, glutaraldehyde, glutaric anhydride and spacer-arms coupling methods were studied for immobilization of triiodothyronine (Ts), thyroxine (T4) and thyroid stimulating hormone (TSH) antibodies on magnetic particles respectively. The effect of the magnetic particle preparation on the couplings was discussed. The influence of coupling conditions on the preparation of magnetic particle antibodies and the assay performance was also investigated. The storage stability and reproducibility of the magnetic particle T3, T4 and TSH antibodies were good enough for use in total T3, total T4 RIA and TSH IRMA. A comparison of five types of magnetic particles from different sources for coupling TSH antibody for TSH IRMA application was made. Silanized magnetic particles and other types of particles showed comparable results. Five TSH antibodies, including two polyclonal and three monoclonal antibodies coupled to silanized magnetic particles respectively, were used in TSH IRMA. It was found that each of them and a commercial monoclonal TSH antibody as label formed good sandwich partners and gave a high signal to low levels of TSH.

Diesel and gasoline engines are the most important sources of energy consuming, emission and global warming. To increase fuel efficiency and reduce emission, air pressure ratio of the engine needs to be further increased. The increase of air pressure is achieved by a compressor wheel in the turbocharger. The compressor wheel needs very complex blade geometry to achieve high pressure ratios. The very latest technique for impeller manufacture is called semi-solid moulding (SSM). This paper will present recent development of SSM including thixo-casting and rheo-casting processes in making aluminium compressor wheels. Experimental results show SSM material has superior microstructure and mechanical properties over cast and is comparable to material machined from solid. Component testing including performance and durability testing proves the SSM compressor wheels emerge as being significantly more durable than cast equivalents and approaching that of machined impellers.

The kinetic distribution patterns of [ 64 Cu]Cu 2+ in normal mice and in mice bearing tumors (HepA, ascitic tumor) after i.v. injection were similar. The i.v. injected [ 64 Cu]Cu 2+ concentrated into mouse liver first and then went to other organs and tissues, such as kidney and tumor. Most of the [ 64 Cu]Cu 2+ injected concentrated into the liver within 4 h, and about 8% of the total [ 64 Cu]Cu 2+ injected concentrated into the tumor cells at 24 h after i.v. injection. About 80% and 90% of the soluble [ 64 Cu]Cu in the livers of tumor-bearing mice and normal mice, respectively, existed as [ 64 Cu]CuMT (metallothionein [MT] is a small protein with many cysteine residues) at 4 h after i.v. injection, while about 43% of the soluble [ 64 Cu]Cu 2+ in tumor cells combined with MT at 6 h after i.v. injection. After 10 days oral administration of 150 μg/g body weight copper acetate, the concentration of MT in tumor cells reduced sharply, from 316 μg/g tissue to 152 μg/g tissue, while it increased slightly, from 375 μg/g tissue to 439 μg/g tissue, in the livers of tumor-bearing mice (HepA, solid tumor). The results suggest that MT contributes to the metabolism of copper that is localized mainly in the liver after copper administration and that copper can concentrate into mouse tumor cells followed by the reduction of MT in tumor cells.

A comparative study of radioiodination of simple aromatic compounds using N-chlorosuccinimide (NCS), N-bromosuccinimide (NBS), N-chlorotetrafluoro-succinimide (NCTFS) and Chloramine-T (CAT) has been carried out in trifluoroacetic anhydride (TFAA) as an aprotic solvent. Optimization of the iodination procedure has been performed using anisole as the model substrate. A fast and simple “one-pot” synthesis via NCTFS, NCS or CAT leads to iodoanisoles with a radiochemical yield of about 70 %. For comparison, toluene and benzene have also been radioiodinated.

Thin selenium films were prepared by cathodic deposition on aluminium foils. The AlSeAl sandwich stacks were used for measurement of the excitation functions of the 76 Se( 3 He,2n) 77 Kr, 77 Se( 3 He,3n) 77 Kr and nat Se( 3 He,xn) 77 Kr reactions up to 3 He-particle energy of 36 MeV. Excitation functions were also measured for the competing reactions 76 Se( 3 He,3n) 76 Kr, 76 Se( 3 He,pn) 77 Br, 76 Se( 3 He,p2n) 76 Br, 76 Se( 3 He,p3n) 75 Br, 76 Se( 3 He,α) 75 Se, 77 Se( 3 He,n) 79 Kr, 77 Se ( 3 He ,4n) 76 Kr , 77 Se( 3 He,pn) 78 Br, 77 Se( 3 He,p2n) 77 Br, 77 Se( 3 He,p3n) 76 Br, 77 Se( 3 He,αn) 75 Se, nat Se( 3 He,xn) 79 Kr and nat Se( 3 He,xn) 76 Kr. Thick target yields were calculated for the formation of krypton and bromine isotopes in 3 He-induced reactions on 76 Se and 77 Se and for krypton isotopes in reactions on natural selenium. The possibilities of production of 77 Kr using 3 He-particle induced reactions on 76 Se, 77 Se and nat Se were investigated. From the viewpoint of yield and purity, for the production of 77 Kr the reactions 76 Se( 3 He,2n) 77 Kr and 77 Se( 3 He,3n) 77 Kr were found to be very suitable, the former at low energies and the latter at relatively higher energies. In the case of 76 Se( 3 He,2n) 77 Kr reaction, a target thickness corresponding to E 3 He = 25 → 15 MeV leads to a theoretical thick target yield of 7.5 mCi 77 Kr/μAh; the 76 Kr impurity at EOB amounts to 0.45%. In the case of 77 Se( 3 He,3n) 77 Kr reaction, on the other hand, for a target thickness corresponding to E 3 He = 36 → 15 MeV the calculated thick target yield of 77 Kr is 11.5 mCi/μAh and the levels of impurities 79 Kr and 76 Kr at EOB amount to 0.35 and 0.36%, respectively.