Retrieval of waste from single-shell tank C-110 resumed in January making it the first waste retrieval operation for WRPS since taking over Hanford's Tank Operations Contract last October. Now, with approximately 90 percent of the waste removed, WRPS believes that modified sluicing has reached the limits of the technology to remove any further waste and is preparing documentation for use in decision making about any future retrieval actions. Tank C-110 is located in C Fann near the center of the Hanford Site. It is a 530,000 gallon tank, built in 1946, and held approximately 126,000 gallons of sludge and other radioactive and chemical waste materials when retrieval resumed. Modified sluicing technology uses liquid waste from a nearby double-shell tank to break up, dissolve and mobilize the solid material so it can be pumped. Because of the variety of waste fon11S, sluicing is often not able to remove all of the waste. The remaining waste will next be sampled for analysis, and results will be used to guide decisions regarding future actions. Work is moving rapidly in preparation to retrieve waste from a second single-shell tank this summer and transfer it to safer double-shell tank storage. Construction activities necessary to retrieve …

Paternal germline exposure to organophosphorous pesticides (OP) has been associated with reproductive failures and adverse effects in the offspring. Methyl parathion (Me-Pa), a worldwide-used OP, has reproductive adverse effects and is genotoxic to sperm. Oxidative damage has been involved in the genotoxic and reproductive effects of OP. The purpose of this study was to determine the effects of Me-Pa on spermatozoa function and ability to fertilize. Male mice were exposed to Me-Pa (20 mg/kg bw, i.p.) and spermatozoa from epididymis-vas deferens were collected at 7 or 28 days post-treatment (dpt) to assess the effects on maturing spermatozoa and spermatocytes, respectively. DNA damage was evaluated by nick translation (NT-positive cells) and SCSA (percentDFI); lipoperoxidation (LPO) by malondialdehyde production; sperm function by spontaneous- and induced-acrosome reactions (AR); mitochondrial membrane potential (MMP) by using the JC-1 flurochrome; and, fertilization ability by an in vitro assay and in vivo mating. Results showed alterations in DNA integrity (percentDFI and NT-positive cells) at 7 and 28 dpt, in addition to decreased sperm quality and a decrease in induced-AR; reduced MMP and LPO was observed only at 7 dpt. We found negative correlations between LPO and all sperm alterations. Altered sperm functional parameters were associated with reduced …

The High Flux Isotope Reactor resumed operation in June of 2007 with a super-critical hydrogen cold source in horizontal beam tube 4. Cold guide 4 is a guide system designed to deliver neutrons from this source at reasonable flux at wavelengths greater than 4 Å to several instruments, and includes a 15-m, 96-section, 4-channel bender. A time-of-flight spectrum with calibrated detector was recorded at port C of cold guide 4, and compared to McStas simulations, to generate a brightness spectrum.

The NSS5/SP-STM2 conference was held in Athens, Ohio July 15-19, 2008. The conference brought together a prestigious group of scientists from all over the globe to focus for 3 ½ days on a variety of nanoscience topics, particularly on nanoscale spectroscopy and spin-polarized scanning tunneling microscopy. The conference was attended by many young scientists as well as senior scientists. Attendees to the conference were drawn from more than 10 countries and included 28 invited speakers, who are the leading scientists in their respective research areas. Included among the invited speakers were 4 plenary speakers - eminent scientists in their fields. The conference was divided into two parallel sessions – the NSS5 session and the SP-STM2 session.

AuxZn1-x alloys undergo a shape memory martensitic transformation whose temperature and nature (continuous or discontinuous) is strongly composition dependent. Neutron diffraction experiments were performed on single crystals of x=50 and 52 to explore the structural changes occurring at the transition temperature. A transverse modulation with wavevector q0=(1/3,1/3,0) develops below the transition temperature, with no observable change in lattice parameter. However, the Bragg peak width shows a broadening suggesting an unresolved rhombohedral distortion similar to what has been observed in NiTi-Fe alloys.