The problems associated with the construction of continuous-duty dc excited ion lasers are indicated. Two solutions to thermal dissipation and bombardment problem which have been experimentally tested appear promising described. These involve use axial magnetic fields high current, low pressure, constricted arcs in large bore tubing metal-walled discharge vessels. influence an field on properties laser is discussed, optical power levels obtained given.

The structure and thermal properties of novel mesoporous inert-gas solids were studied by synchrotron x-ray diffraction. materials prepared injecting a jet helium containing dilute amounts inert atoms molecules (Ne, Kr, ${\mathrm{N}}_{2}$) into superfluid helium. characteristic size the constituent building blocks is $\ensuremath{\sim}60\AA{}$, density $\ensuremath{\gtrsim}{10}^{20}\mathrm{impurity}$ per c${\mathrm{m}}^{3}$. Kr ${\mathrm{N}}_{2}$ are stable outside liquid He, up to...

We have used x-ray diffraction and ultrasound techniques to study the structure of mesoporous impurity--helium solids created after injection impurity particles $({\mathrm{D}}_{2},$ Ne, ${\mathrm{N}}_{2},$ Kr) into a volume superfluid ${}^{4}\mathrm{He}.$ Clusters impurities with size order $50\ifmmode\pm\else\textpm\fi{}20 \AA{}$ density $\ensuremath{\sim}{10}^{20} \mathrm{impurities}/{\mathrm{cm}}^{3}$ were observed by diffraction. The presence wide distribution pore sizes in Im--He was...

He: Vortices and turbulence PACS 61.46.Km -Structure of nanowires nanorods (long, free or loosely attached, quantum wires rods, but not gate-isolated embedded wires)Abstract -We demonstrate that laser ablation a gold target immersed in superfluid normal fluid helium leads to the formation elongated nano-fragments.In phase these nano-fragments aggregate into filaments with extremely large aspect ratios displaying metallic electric conductivity.We attribute this unusual structure coalescence...

Neuropsychiatric sequelae of carbon-monoxide poisoning are now well documented.A recent Lancet annotation (1962) referred, however, to the less-well-recognized occurrence postanoxic encephalopathy after a period apparent clinical recovery ; series five such cases reported by Plum et al.(1962) is quoted.The present case provides further example delayed neurological and psychiatric effects coal-gas poisoning; it demonstrates in addition temporary improvement.

Thin silver nanowires were found to decay upon heating up 300 K, but doping by copper stabilizes them.

Webs consisting of nanowires made gold, platinum and mercury were produced by the technique based on laser ablation metals inside superfluid helium. Their morphology structure as well their electrical conductivity have been studied. Diameters gold are 4.5 3 nm, respectively. Fortunately, they close to diameters nanospheres these metals, which, known from literature, possess anomalous catalytic activity. Web resistivities for all up room temperature controlled conductive electron scattering a...

Laser ablation of metals in superfluid helium has been used to obtain nickel, indium, and lead nanowire bundles. Wires 5–8nm diameter demonstrate metallic conductivity are coupled with one another by point contacts. It is shown that the wire bundles attach sharp tips introduced into region condensation up 1cm long. The high intensity low threshold electron field emission explained smallness radius individual wires long length a bundle. superconducting transition temperature shifted downwards...

A dramatic effect of quantized vortices in superfluid helium on the rate coalescence suspended impurities has been predicted; such a catalytic process should result formation fiber-like structures having primarily nanothickness. That be valid for any impurity and it may used as basis universal method producing nanowires nanotubes. Experiments imbedding molecular hydrogen into liquid have supported these conclusions. They showed that: (i) normal He led to spherical microparticles carried by...

Views Icon Article contents Figures & tables Video Audio Supplementary Data Peer Review Share Twitter Facebook Reddit LinkedIn Tools Reprints and Permissions Cite Search Site Citation E. B. Gordon, A. V. Karabulin, I. Matyushenko, D. Sizov, Khodos; The electrical conductivity of bundles superconducting nanowires produced by laser ablation metals in superfluid helium. Appl. Phys. Lett. 30 July 2012; 101 (5): 052605. https://doi.org/10.1063/1.4742330 Download citation file: Ris (Zotero)...

It is shown from an analysis of x-ray structural and IR spectroscopic studies that when impurity particles are introduced into liquid or solid helium, the clusters formed in cold part a gas jet have pronounced spatial separation impurities with different volatility. In particular, condensation partially dissociated diatomic molecules atoms highly concentrated near on surface clusters. Segregation this kind preserved condensate which consists stuck together porous structure; helium isolated....

Abstract Two different types of experiments were performed. In the first experiment, we studied low-temperature condensation vaporized graphite inside bulk liquid helium, while in second single carbon atoms together with H 2 , O, and CO molecules helium nanodroplets. The leads to formation partially graphitized carbon, which indicates high temperatures, supposedly higher than 1000°C, during condensation. Possible underlying processes responsible for instant rise temperature are discussed....

The copper-doped gold nanowires (4 nm in diameter) were produced by the novel technique based of laser ablation Au–Cu alloy inside superfluid helium. principle method is using quantized vortices as 1D template for condensation products into thin threads. applied catalyst СО oxidation with oxygen. activity deposited on glass filters was compared that monometallic and bimetallic Au Cu particles (3–8 alumina traditional deposition–precipitation impregnation techniques. apparent activation...