This paper describes blistering of rhenium following 21 keV He-ion irradiation at temperatures between 300 K and 1200 K. Blistering starts at 300 K at a dose of 3×10 ions/cm. The most probable blister diameter varies from 4400 Å at 300 K to 10100 Å at 1200 K. The blister depth τ, the blister diameter φ and the blister height h show a distribution. From the observations one could derive the following relationships: h = 0.35φ; τ=3.43φ. The erosion yield E due to blistering is function of dose E =0.51 atoms/ion at 3×10 ions/cm, E =0.56 atoms/ion at 6×10 ions/cm and E =0.14 atoms/ion at 3×10 ions/cm. The sputtering yield S (21 keV) is estimated to be ∼0.1 atom/ion. The corresponding surface regression is 44Å at 3×10 ions/cm and 1323 Å at 9×10 ions/cm. Surface regression has therefore little influence on the observations at low doses. [ABSTRACT FROM AUTHOR]
The influence of 1 MeV electron irradiation at 300 K on the diameter distribution of helium bubbles after 5 keV He+ implantation in nickel and in Metglas 2826 MB (Fe40 Ni38 Mo4 B18) is investigated. Electron irradiation induces additional bubble growth in both materials. Helium bubble growth in nickel as function of damage dose (2-18 dpa) is as effective during e− irradiation of a He+ pre-implanted specimen as it is the case during further He+ implantation. This indicates that a significant proportion of the implanted helium resides outside the bubbles after He+ implantation and that this helium precipitates into the bubbles during electron irradiation. In the amorphous alloy, the helium bubbles grow less during electron irradiation than during further He+ implantation. [ABSTRACT FROM PUBLISHER]
Oecologia [Oecologia] 1984 Mar; Vol. 61 (3), pp. 302-310.
Abstract
| (1) Paropsis charybdis, the Eucalyptus tortoise beetle, is a serious defoliator of several Eucalyptus species in New Zealand. A series of laboratory experiments demonstrated the growth characteristics of larvae and adults when feeding on E. viminalis at 20°C. These were used as the data bases for quantifying its trophic relationships in terms of dry matter, energy and nitrogen. (2) The four larval stages lasted 4.0, 2.5, 3.0 and 9.5 days. Growth was exponential until the second day of the fourth instar, when the superficially inactive prepupal stage began. The pupal stage lasted 9.5 days. Female beetles started to lay eggs 15 days (av.) after eclosion. (3) Larvae attained a mean maximum dry weight (dwt) of 53.29 mg. Reproductive females weighed 63.40 mg, and males 46.71 mg. (4) The guts and their contents contributed up to 50% of total larval dry weight and 15% of adult dry weight. (5) Studies of the trophic relationships of P. charybdis larvae were based upon budgets whereby consumption (C) equals the sum of production (P), respiretion (R) and egesta (FU). Production was divided into gut-free larval production (P L ) and exuvia (P * )+R+FUin J: 3,561.5 = (491.3+43.4) + 284.5 +2,574.9 in mgN: 4.001 = (2.078 + 0.200) +1.657 (no R term) . P = P EX + P L * + P EX = C - FU - (P = P c + P c = C - FU - (P = P L reflects the change in body weight and P * + P EX + P AD reflects the change in body weight and P R + 0.252) + 0.285. The budget assumes that male P AD + P R ) + R +FU in mg dwt: 27.36 = (ΔP +2.25) +R + 14.53 in J: 591.1 = ΔP + 65.4) + 82.0 +362.6 in mgN: 0368 = (ΔP AD + 0.252) + 0.285. The budget assumes that male P R can be assumed to equal zero over a long term, although fluctuations were apparent during the experimental period. (7) The amount of leaf material removed but not eaten by larvae (NU) was 22.6 mg, 462.4 J or 0.526 mgN. Thus, the total material removed (MR = C +NU) was 194.3 mg, 3978.9 J or 4.527 mgN. NU per day for an average adult was 4.86 mg, 99.5 J or 0.113 mgN. Therefore adults removed 32.33 mg, 659.9 J or 0.751 mgN per day. (8) Ecological efficiencies (energy) of P. charybdis larvae (using P = P C + P M and A = assimilation + C - FU ) were: net ecological efficiency (P.A. AD )=56.8%, gross ecological efficiency (P.C L * )=26.8%, P.R. EX =121.5%. Adult efficiencies were: P. A. -1 =28.6%, P.C. -1 )=15.2%, assimilation efficiency (A.C. -1 =38.7% and P.R. -1 =55.7%. Efficiencies in terms of nitrogen were (larval data followed by adult data in parentheses): P.A. -1 =97.2 (71.4)%, P.C. -1 =11.1%, A.C. -1 =38.7% and P.R. -1 =55.7%. Efficiencies in terms of nitrogen were (larval data followed by adult data in parentheses): P.A. -1 =97.2 (71.4)%, P.C. -1 =56.9 (39.5)% and A.C. -1 =58.6 (55.3)%. (9) Regressions were calculated to link larval length (1) or larval live weight (lwt) and the dry weight of leaf material removed from a tree by that individual so that these results can be readily applied to field studies: logMR = -2.042 + 3.418 log1 logMR = -0.728 + 1.023 log 1wt.
