Numerical simulation for electron transport in newly designed large volume ion source is carried out by simultaneously solving several differential equations. It should be noted from the computation that the electron produced by rf discharge at the circumferential region of large volume ion chamber transports to the central region of chamber by the gradient of magnetic flux density. This computational result is supported quantitatively by experimental results published recently.¹ It is also found that the increase in rf frequency decreases the cyclic drift distance in x (circumferential) direction and increases the frequency of cyclic drift motion.

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Fifteen Zr-based alloys with C15 type Laves phase for the negative electrode of Ni-MH battery were examined. Their compositions were designed by considering crystal structure, average atomic radius and average electronegativities of the alloys. The most part of them had a large discharge capacity over 380mAh/g and their electrochemical characteristics were excellent even for discharging in high-rate current density. The relationships between the hydride formation enthalpy(ΔH⁰) and the lattice volume and the average electronegativity of alloys were discussed on the basis of experimental results.

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It is a serious problem that excess helium-ion etching greatly deceases superconducting transition temperature (T_c) and critical current density (J_c) of Bi_1.6Pb_0.4Sr₂Ca₂Cu₃O_x. Thus, the influence of the etching on T_c and J_c has been investigated for the Bi oxide. A critical DOSE (D_c) to maintain high T_c above 100K is defined and evaluated. The D_c value is about 3.2×10¹⁷(ions/mm²) for the helium-ion etching.

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The rapid clonal propagation of Phalaenopsis plantlets by shake culture was investigated. The plantlets propagated by shake culture were rapidly grown compared to agar culture. The dry weight of shoots cultured in shake culture was 5 times largar, and maximum shoot length was 2 times greater compared to that of agar culture. Protocorm like body (PLB) production was also stimulated by shake culture. The dry weight content (DW/FW ratio) of the plantlets grown in shake culture was slightly lower compared to agar culture. The plantlets thus produced were transplanted into soil and both agar- and shake-cultured plantlets were well reestablished in soil.

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The effects of vatrious medium components on induction of somatic embryos from adventitious root cultures of Atropa belladonna in shake culture were investigated. The effects of H₂PO₄^- and sucrose were most serious, that is, the number of somatic embryos was the highest level at the H₂PO₄^- concentration of 9mM (7417embryos/l) and the sucrose concentration of 10g/l (1778embryos/l).

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