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Notes: The spin–orbit selectivity of angle-resolved photoelectron spectra was used to provide new information on the electronic structure, symmetry, and decay dynamics of members of the autoionizing Tanaka–Ogawa Rydberg series in CO2. This represents the first time that spin–orbit selectivity has been used to obtain such information for a polyatomic molecule. The spin–orbit photoelectron branching ratios were used to show that the angular momentum quantum number λ of the excited Rydberg electron does not change upon autoionization. Furthermore, a consideration of the present results together with previous calculations of the relative intensities of the discrete and continuum ionization channels shows that the most probable electron configuration for the Tanaka–Ogawa Rydberg series is ...(πu)3(πg)4ndδg and that autoionization proceeds primarily via a dδg→εfδu process for the totally symmetric vibronic components of the ion. The asymmetry parameter β was determined for individual spin–orbit components of the various vibronic bands of the X˜ 2Πg state and is discussed in terms of recent theoretical calculations. The Rydberg series appears to be well described by Ωcω coupling, even for relatively low principal quantum numbers. The general utility of this technique for autoionizing Rydberg states and its extension to multiphoton ionization of Rydberg states that lie below the first ionization threshold are discussed.

Notes: Vibrational branching ratios and photoelectron angular distributions are reported for the 5σ−1 photoionization channel of CO in the range 16 eV〈hν〈45 eV. Striking non-Franck–Condon effects are observed in both the branching ratios and angular distributions as a result of various autoionizing states and a σ shape resonance that lie in this spectral range. The goal of the present measurement was to observe definitive evidence for the σ shape resonance via its non-Franck–Condon effects on the vibrational ionization channels. Guided by recent calculations [Smith, Lynch, and McKoy, J. Chem. Phys. 85, 6455 (1986)], we examined the broad structure in the vibrational branching ratios and angular distributions in the range 25 eV 〈hν〈40 eV. There, we found clear evidence for the σ shape resonance in the quantities β(v+=0 and 1) and σ(v+=2)/σ(v+=0). Substantial differences between theory and experiment for the σ(v+=1)/σ(v+=0) branching ratio, however, serve to define the limitations of the current single-channel picture for this process.

Notes: A new oesophageal intubation detector device, the Fenem CO2 detector, was used in 100 patients intubated during anaesthesia for elective surgery. This new device was 100% accurate in the differentiation between tracheal and oesophageal placement of a tube.

Notes: It has been shown previously (John 1966; Currie & Hayes 1969) that Hadamard compressible elastic materials are the only ones for which three linearly polarized finite-amplitude plane waves, one longitudinal and two transverse, may propagate in any direction when the material is maintained in a state of arbitrary static finite homogeneous deformation. Here we first obtain simple explicit expressions for the three wave speeds and a simple characterization of the polarization directions of the transverse waves. Also, although the theory is non-linear, it is seen that the three waves may be superposed: they do not interact. Special directions, called acoustic axes, are introduced. These are the only directions along which circularly polarized transverse waves may propagate. They are determined only by the basic static deformation of the material. Results are expressed in terms of the angles that the propagation direction makes with the acoustic axes. Then, the energy flux and energy density of the waves are considered. Relations between the projection on to the propagation direction of the energy flux vector and the energy density are derived for each individual wave. Finally, periodic transverse waves are considered.

Notes: Seven cultivars of white clover (Trifolium repens L.) (Kent, S184, Huia, Menna, Donna, Alice and Nesta) and a commercial mixture, ‘Ensign’, were strip-seeded into an upland perennial rye-grass (Lolium perenne L.) sward in late June 1986. Swards were first grazed by sheep, either on 5/6 August (early) or on 19/20 August (late) and then every 14–21 days (frequently) or 28–42 days (infrequently) during 1986, followed by a common grazing regime in 1987. During April to mid-June 1988 the swards received either a moderate amount of nitrogen or none and were cut frequently or once only in mid-June. Growth of individual seedlings was assessed before and after grazing during 1986 and stolon accumulation and distribution and sward colonization were assessed during 1987 and 1988.All cultivars emerged rapidly and satisfactorily and there were no consistent significant differences in the overall dry matter accumulation per seedling during establishment. During the first autumn the proportion of the aboveground biomass removed during grazing was smallest in Kent (c. 20%) and largest in Nesta (c. 40%). Kent and S184 produced most leaves and stolons and the greatest length of stolons per seedling and per individual stolon, and Nesta and Alice the fewest leaves and stolons and shortest stolons. Seedlings grazed early had heavier and longer stolons than those grazed late; those grazed frequently had more leaves, stolons and growing points than those grazed infrequently, especially following early grazing.During 1987 Kent and S184 had consistently the largest number of stolon growing points, and weight and length of stolons per unit area; these two cultivars and Nesta also colonized the sward more rapidly than the other cultivars. All cultivars contributed substantially and similarly to herbage production in late September. There were no residual effects of the 1986 treatments after the summer of 1987.During 1988 additions of nitrogen fertilizer at 100 kg N ha-1 or allowing the herbage to remain undefoliated between mid-April and mid-June both independently halved the number of stolon growing points per unit area; together they reduced it by 80%. Nitrogen also, on average, halved stolon weights but less so in Nesta, Alice and Huia and more so in all other cultivars. Infrequent defoliation greatly decreased stolon weights in Kent and S184 but had no significant effects on the other cultivars. Sward colonization was almost complete by June and entirely so by October for all cultivars in all treatments.Implications of the results for the after-management of strip-seeded white clover are discussed.

Notes: Small plots of a Festuca-Agrostis upland sward on a peaty gley podsol were strip-seeded during late June 1986 with white clover cvs Aberystwyth S184 or Menna at 4 kg ha−1 and defoliated early (20 August) or late (3 September) and then frequently or infrequently (every 2 weeks or 4 weeks) until the end of September. All plots were defoliated in early November, at 3-weekly intervals during the growing season in 1987 and then grazed rotationally during 1988.Satisfactory seedling establishment, representing 46% emergence, was achieved 5 weeks after sowing. The differential defoliation regimes had no persistent significant effects on clover development. S184 soon produced more leaves per seedling than Menna and a smaller proportion of its leaf number and weight were removed at each defoliation. Following large losses of leaves over the 1986–87 winter, SI84 had significantly more leaves per stolon than Menna; subsequently it also colonized the sward at a quicker rate. During 1987 amounts of herbage harvested (6.1 t ha−1) were similar with the two clover cultivars, with S184 contributing 47% and Menna 44% of this respectively. SI84 made a larger contribution to yield during May and June but Menna was more productive during September and October. During 1988 clover populations were maintained with rotational grazing without additional fertilizer inputs.The results show that, despite initial soil and climatic contraints, both small and medium-leaved clovers can be strip-seeded into upland swards with large subsequent benefits to yield and herbage quality. However, they also indicate the need for further experiments to determine the influence of sward morphology and defoliation regime on stolon branching rates and accumulation of growing points which, in turn, govern sward colonization.

Notes: We present time-resolved experimental measurements of the electron distribution function f(v(parallel),v⊥,t) in a pulsed, partially ionized, electron cyclotron resonance (ECR)-produced plasma. The discharge has some characteristics similar to those used in plasma processing applications. These properties include ECR production in a strong magnetic field and low electron temperature (Te〈5 eV). In addition, electron-neutral collisions play an important role. A novel analyzer is used to study the dependence of f(v(parallel),v⊥,t) on velocities both parallel and perpendicular to the magnetic field. This information cannot be obtained with a simple Langmuir probe. The temporal evolution of f(v(parallel),v⊥,t) is examined during plasma formation, with the source biased, with the source grounded and in the afterglow.