Radicals in carbonaceous residue deposited on mordenite from methanol

It is shown that control of the degree of coking can lead to the observation of hyperfine structures in the carbonaceous residues deposited from methanol over mordenite (H-MOR) at temperatures relevant to the conversion of methanol to hydrocarbons. EPR measurements of the catalyst samples at various times on stream have been recorded, with a rich hyperfine splitting pattern observed in the early stages of the reaction. Interpretation of the EPR data with the aid of density functional theoretical calculations has afforded the first definitive assignment of the radical cations formed in high temperature coke. The results detail a shortlist of six species: 2,3/2,6/2,7-dimethylnaphthalenium, 2,3,6-trimethylnaphthalenium, 2,3,6,7-tetramethylnaphthalenium, and anthracenium radical cations whose proton hyperfine splitting profiles match the experimental spectra; 2,3,6,7-tetramethylnaphthalenium showed the best agreement. The observation of these particular isomers of polymethylnaphthalene suggest the formation of more highly branched polyaromatic species is less likely within the confines of the H-MOR 12-membered ring channel. These radicals formed when the catalyst is active may constitute key intermediates in the conversion of methanol to light olefins

Response calculations based on an independent particle system with the exact one-particle density matrix: polarizabilities

Recently, we have demonstrated that the problems finding a suitable adiabatic approximation in time-dependent one-body reduced density matrix functional theory can be remedied by introducing an additional degree of freedom to describe the system: the phase of the natural orbitals [Phys. Rev. Lett. 105, 013002 (2010), J. Chem. Phys. 133, 174119 (2010)]. In this article we will show in detail how the frequency-dependent response equations give the proper static limit ($\omega\to0$), including the perturbation in the chemical potential, which is required in static response theory to ensure the correct number of particles. Additionally we show results for the polarizability for H$_2$ and compare the performance of two different two-electron functionals: the phase-including L\"owdin-Shull functional and the density matrix form of the L\"owdin-Shull functional.Comment: 10 pages, 6 figure

Radioisotope Heaters for the Thermal Control

The recent development and fabrication of a series of small radioisotope heaters has opened the door to an entirely new and unique tool for thermal control. The devices are completely passive and generate heat with a reliability of 1. The design, and construction of these heaters is discussed along with qualification tests to which the heaters have been subjected. These tests include crush forces of 20,000 pounds, thermal shock from 1700°F to -320°F, and impact into granite at a velocity of 355 ft/sec. Radiation \u27shielding data are presented which will permit preliminary design estimates. General licensing requirements are also included. Some applications are discussed with comparisons made between radioisotope and electrical heating systems. In these comparisons a radioisotope heater shows both a weight and cost advantage over solar cells or batteries. Typical radioisotope heater characteristics over a power range of 1 to 50 watts are presented

COST OF SEGREGATING NON-TRANSGENIC GRAINS AT COUNTRY ELEVATORS IN SOUTH DAKOTA

Genetically modified grains have rapidly become popular among producers across U.S. Some consumers, particularly in the EU, South Korea, and Japan, are unwilling to purchase products containing ingredients from genetically modified or transgenic crops. This paper develops a model to represent costs of segregating non-transgenic grains at country elevators and simulates these costs at representative elevators in South Dakota under alternative scenarios employing a case study approach. The overall cost of segregating non-transgenic grains under a zero rejection rate ranged from 1.5 to 21.7, 1.2 to 11.3, and 1.3 to 16.4 cents per bushel, for corn, soybeans, and wheat, respectively.Crop Production/Industries, Research and Development/Tech Change/Emerging Technologies,

Segregating Transgenic Grains:Results of a Survey Among Country Elevators in South Dakota

Using responses from a mail survey conducted among 203 South Dakota grain elevator managers in 2002, we analyzed the degree to which their elevators were prepared to segregate non-transgenic from commodity grains. Results showed four percent of the managers expected their own, and ten percent expected a competing elevator be dedicated to handling only non-transgenic or identity preserved grains within five years. Only four and one percent of the elevators handled non-transgenic corn and soybeans, respectively, and only one percent participated in identity preserved grains. One in five elevator managers in the state reported having tested corn for transgenic material, and none of the respondents conducted any genetic testing for soybeans in 2001. Further, 17 and two percent reported having buyers inquire about segregated non-transgenic or identity preserved corn, and such soybeans, respectively. Among those handling corn (soybeans), 29 (30) percent was familiar with the non-transgenic corn (soybean) market and 53 (58) percent was willing to participate in these markets at an average premium of 28 (37) cents per bushel. One in five elevators are able to participate in segregating non-transgenic and commodity grains without additional capital outlays. Thus, if a sizable demand for non-transgenic grains develops, the South Dakota grain handling industry appears ready to deal with it.transgenic, grain segregation, Agricultural Experiment Station

SEGREGATING TRANSGENIC GRAINS: RESULTS OF A SURVEY AMONG COUNTRY ELEVATORS IN SOUTH DAKOTA

Using responses from a mail survey conducted among 203 South Dakota grain elevator managers in 2002, we analyzed the degree to which the elevators were prepared to segregate non-transgenic from commodity grains. Only 17 and two percent reported having buyers inquire about segregated non-transgenic or identity preserved corn, and such soybeans, respectively. Among those handling corn (soybeans), 53 (58) percent were willing to participate in non-transgenic corn (soybean) markets at an average premium of 28 (37) cents per bushel. It appears that one in five elevators are able to participate in segregating non-transgenic and commodity grains without additional capital outlays.Crop Production/Industries, Research and Development/Tech Change/Emerging Technologies,

XMM-Newton reveals ~100 new LMXBs in M31 from variability studies

We have conducted a survey of X-ray sources in XMM-Newton observations of M31, examining their power density spectra (PDS) and spectral energy distributions (SEDs). Our automated source detection yielded 535 good X-ray sources; to date, we have studied 225 of them. In particular, we examined the PDS because low mass X-ray binaries (LMXBs) exhibit two distinctive types of PDS. At low accretion rates, the PDS is characterised by a broken power law, with the spectral index changing from ~0 to ~1 at some frequency in the range \~0.01--1 Hz; we refer to such PDS as Type A. At higher accretion rates, the PDS is described by a simple power law; we call these PDS Type B. Of the 225 sources studied to date, 75 exhibit Type A variability, and are almost certainly LMXBs, while 6 show Type B but not Type A, and are likely LMXBs. Of these 81 candidate LMXBs, 71 are newly identified in this survey; furthermore, they are mostly found near the centre of M31. Furthermore, most of the X-ray population in the disc are associated with the spiral arms, making them likely high mass X-ray binaries (HMXBs). In general these HMXBs do not exhibit Type A variability, while many central X-ray sources (LMXBs) in the same luminosity range do. Hence the PDS may distinguish between LMXBs and HMXBs in this luminosity range.Comment: 4 pages, 2 figures. To appear in proceedings of IAUS230: "Populations of High Energy Sources in Galaxies", 14-19 August 2005, Dublin, Eds E.J.A. Meurs and G. Fabbian

Improvement of Thymopoiesis after Hematopoietic Stem Cell Transplantation by Cytokines: Translational studies in experimental animal models

Allogeneic hematopoietic stem cell transplantation (AlloHSCT) is a powerful treatment modality that is frequently applied as part of treatment of hematological malignancies, aplastic anemia and inborn errors of hematopoietic progenitor cells. A major drawback of alloHSCT is the treatment related morbidity and treatment related mortality (TRM), which are largely accounted for by opportunistic infections. Those infections occur during a prolonged period (1-2 years), characterized by an impaired reconstitution of the adaptive immune system. Especially, the recovery of naïve T cells and thymopoiesis are protracted after transplantation, but are considered pivotal for restoration of anti-infectious immunity. This thesis has experimentally addressed new strategies that may improve thymopoiesis, including the post-transplant administration of cytokines that are physiologically involved in the differentiation and proliferation of thymocytes