Radiation and hot electron temperature measurements of short-pulselaser driven hohlraums

We have performed measurements of the radiation and the hot electron temperature in sub-millimetre size hohlraums driven by a high intensity short-pulse laser. The results indicate that radiation temperatures 80 eV can be obtained with 20 J of laser energy delivered on target. Radiation-hydrodynamics simulations indicate an absorption into thermal X-rays of 1–2%, with peak temperatures similar to those measured experimentally.     

Rapid americium separations from complex matrices using commercially available extraction chromatography resins

Journal of Radioanalytical and Nuclear Chemistry - A method for rapid separation of americium from complex matrices by use of two commercially available extraction chromatography resins is...     

Development of automated separations for actinides analysis

Journal of Radioanalytical and Nuclear Chemistry - Novel methods for sample preparation by adapting an automated chromatography system to radiochemical analysis for analysis of trace impurities is...     

Photoelectron spectra of halides

High resolution photoelectron spectra, obtained with He I (584 Å) resonance radiation, are reported for ClF, ClF₃, BrF₃ and BrF (partial spectrum). In some cases Ne I (736–744 Å) radiation has also been used. Spinorbit and vibrational fine structure is resolved for the ground ²II states of ClF⁺ and BrF⁺; values obtained for ClF⁺ and ζ = 630 cm^-1, v′ = 870 cm^-1, and for BrF⁺ ζ = 2600 cm^-1, v′ = 750 cm^-1. From the vibrational envelope of the X ²∏ states, a bond length change of δr _e (-)0·10 Å for ClF⁺ and BrF⁺ is estimated. Ab initio SCF-MO calculations for ClF and ClF₃ are used to aid in the interpretation of the spectra via Koopmans' theorem. A considerable amount of charge delocalization in the trifluorides is inferred from the photoelectron spectra, and this is borne out by the calculations.     

Customer Service vs Trim Waste in Corrugated Box Manufacture

Many approaches to the problem of arranging customer orders for cutting or corrugation have focused on the minimization of trim waste. This views the corrugator more or less in isolation. When downstream machines or customer due-dates exist, however, customer service may suffer from the desire to keep scrap at a low level. Thus, if slightly higher levels of waste were accepted, the production scheduler might be able to improve performance regarding due dates.We developed a simulation model, for Domtar Packaging Ltd, of a corrugated cardboard box factory, which included the corrugation process and four finishing machines. Customer orders were generated via empirical and theoretical probability distributions, then sent through the model according to one of several scheduling rules. This allowed the relationship between various levels of trim waste and customer service to be viewed. Results of the simulation experiments, as well as a discussion of the model itself, are given. Comments and conclusions regarding both our model and corrugator algorithms in general are presented in the light of the role of the human scheduler in plants of this type.     

A study of measuring techniques for airborne sound insulation in buildings

Some comparison measurements of airborne sound insulation have been made in a laboratory house, with 12 organizations taking part. Using their current procedures resulted in a large spread in the results obtained, due to differences in equipment and techniques. The various steps in the measurements have been studied in detail, to determine how discrepancies could arise, and to establish a rationalized technique by which they would be minimized. The measuring teams repeated the comparison exercise using such a technique, and a smaller spread in the results was found. The instrumentation was developed further and measurements were made between rooms of various sizes. The results were repeatable within small limits. The consequences for further standardization in the measuring procedure are discussed.     

Hydrogen-deuterium exchange signature of porcine cerebroside sulfate activator protein

Hydrogen-deuterium exchange can be a sensitive indicator of protein structural integrity. Comparisons were made between cerebroside sulfate activator protein (CSAct) in the native state and after treatment with guanidine hydrochloride plus dithiothreitol. Native protein has three internal disulfide bonds and treated protein has no internal disulfide bonds. The comparisons were made using hydrogen-deuterium exchange measured by electrospray ionization mass spectrometry, percentage alpha-helical content measured by circular dichroism and biological activity measured by the ability to support arylsulfatase A-catalyzed sulfate hydrolysis from cerebroside sulfate. In acidic solvent native protein has 59 exchange refractory protons and treated protein has 20 exchange refractory protons (44 and 14% of the exchangeable proton populations, respectively). In native protein the size of the exchange refractory proton population is sensitive to changes in pH, temperature and the presence of a ligand. It is uninfluenced by the presence or absence of glycosyl groups attached to Asn21. Helical content is virtually identical in native and treated protein. Biological activity is significantly reduced but not obliterated in treated protein. The hydrogen-deuterium exchange profile appears to be a sensitive signature of the correctly folded protein, and reflects a dimension of the protein structure that is not apparent in circular dichroic spectra or in the ability of the protein to support arylsulfatase A-catalyzed sulfate hydrolysis from sulfatide. The hydrogen-deuterium exchange profile will be a valuable criterion for characterizing mutant forms of CSAct produced by recombinant and synthetic paradigms and also the native and mutant forms of related proteins.     

Formation of a Dimer of Trinuclear Helicates which Encapsulates an Array of Six Hydrogen‐Bonded Anions

The amine‐containing ligand L, composed of two bidentate pyridyl‐thiazole moieties linked by a 1,3‐diaminophenylene unit, reacts with copper(II) ions to form a dinuclear double helicate [Cu₂L₂]⁴⁺. Reaction of [Cu₂L₂]⁴⁺ with dihydrogen phosphate (0.5 equivalents) gives the unsaturated dinuclear double helicate [Cu₂L₂(OPO₃H₂)]³⁺. [Cu₂L₂(OPO₃H₂)]³⁺ further reacts with another 0.5 equivalents of dihydrogen phosphate to give a trinuclear circular helicate which then self‐assembles into a hexameric cluster [{Cu₃L₃(OPO₃H₂)₃}]²⁶⁺.     

Practical solvent system selection for counter-current separation of pharmaceutical compounds

Counter-current chromatography (CCC) is a technique that shows a lot of potential for large scale purification. Its usefulness in a "research and development" pharmaceutical environment has been investigated, and the conclusions are shown in this article. The use of CCC requires the development of an appropriate solvent system (a parameter of critical importance), a process which can be tedious. This article presents a novel strategy, combining a statistical approach and fast HPLC to generate a three-dimensional partition coefficient map and rapidly predict an optimal solvent system. This screen is performed in half a day and involves 9 experiments per solvent mixture. Test separations were performed using that screen to ensure the validity of the method.     

A Crystallographic Study of a Highly Substituted Imidazolinone, (3S,4S,5R)-3-(((S)-4-((1H-Indol-3-yl)Methyl)-5-Oxo-4,5-Dihydro-1H-Imidazol-2-yl)Amino)-4-((Tert-Butyldimethylsilyl)Oxy)-5-Hydroxypiperidin-2-One

Abstract  

The title compound 1 has been prepared from the condensation product of a silyl protected amino-oxazoline lactam (3) and Cbz-protected l-tryptophan (4) after hydrogenolysis of the carboxybenzyl protection group. The synthesis and crystal structure of 1 is described. The compound crystallized from DMSO in the monoclinic system, P2₁ space group with unit cell parameters a = 9.4029(25), b = 6.2828(12), c = 20.681(45), and β = 96.505(16), Z = 2 and a cell volume of V = 1213.9(2) ?³. In the crystal lattice, 1 forms an extensive hydrogen bonded framework consisting of interconnected dimeric chains.