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The feasibility of joining laser metal deposited Ti6Al4V sheets using laser beam welding was investigated in this article. The additive manufactured sheets were joined using a 3 kW CW YLS-2000-TR ytterbium laser system. The mechanical properties and microstructure of the welded additive manufactured parts (AM welds) were compared with those of the wrought sheets welded using the same laser process. The welds were characterized and compared in terms of bead geometry, microhardness, tensile strength, fractography, and microstructure. The differences in characteristics are majorly found in the width of the bead and tensile strength. The bead width of AM welds appear wider than the wrought welds, and the wrought welds exhibited higher tensile strength and ductility than the AM welds.

A simulation model has been previously established to calculate the absorbed gamma dose rate inside a room by exploiting the MCNP5 simulation software. This study applies that model on rooms built from different types of building materials. The materials are collected from the North-Sinai Peninsula in Egypt and from the Gaza Strip in Palestine. The Palestinian and the Egyptian samples are compared to see if there is any correlation between them.

The uptake rate of95mTc,83Rb, and65Zn by soybean plants cultivated in soil was measured during 2≈247 hrs by a multitracer technique. The uptake amount in most of the leaves and stems increased up to 150≈200 hrs after the administration of the multitracer and then decreased with time. The uptake amount of65Zn in the youngest fruit increased until 120 hrs and then decreased with time, and83Rb uptake reached almost a constant amount after 120 hrs. On the other hand, the uptake amount of95mTc in the youngest fruit increased continuously up to 247 hrs. The behavior of elements in the leaves and stems was analyzed mathematically with the second order function,Ar=c+k1t+k2t2, 0

The direct absorption of atmospheric elements via soybean leaves has been studied using a radioactive multitra œr technique. Soybean was cultivated until it bore seeds in a box under no-rain conditions and with introduction of multitracer-adsorbed cellulose powders. The radioactive nuclides of 40 elements were produced from Au target irradiated with14N, and the nuclides with relatively long half-life of the elements Sc, Mn, Co, As, Se, Rb, Sr, Y, Eu, Gd, Yb, Re, and Ir were dominantly observed in each part of soybean plant.

The chemical states of iron in sixteen Antarctic meteorites belonging to H-group chondrites were studied by means of Mossbauer spectroscopy. An Fe-Ni alloy, troilite, paramagnetic Fe(III), and two kinds of paramagnetic Fe(II) were observed in each meteorite. The Mossbauer parameters indicated that the Fe(II) components can be assigned to olivine and some pyroxenes. The relative area intensities of Fe(III) in the chondrites correlated positively with iodine content, which was determined by radiochemical neutron activation analysis, and those of two Fe(II)-species correlated negatively with the content. On the basis of the data on the halogen and the Mossbauer spectrocopy, the terrestrial contamination on Antarctic meteorites is discussed.