Surface drilling technologies for Mars

Rock drilling and coring conceptual designs for the surface activities associated with a manned Mars mission are proposed. Straightforward extensions of equipment and procedures used on Earth are envisioned for the sample coring and shallow high explosive shot holes needed for tunneling and seismic surveying. A novel rocket exhaust jet piercing method is proposed for very rapid drilling of shot holes required for explosive excavation of emergency radiation shelters. Summaries of estimated equipment masses and power requirements are provided, and the indicated rotary coring rigs are scaled from terrestrial equipment and use compressed CO2 from the Martian atmosphere for core bit cooling and cuttings removal. A mass of 120 kg and power of 3 kW(e) are estimated for a 10 m depth capability. A 100 m depth capacity core rig requires about 1150 kg and 32 km(e). The rocket exhaust jet equipment devised for shallow (3m) explosive emplacement shot holes requires no surface power beyond an electrical ignition system, and might have a 15 kg mass

Proximity Effect - Amorphous Sn-Fe, Amorphous Bi-Fe Films

Journals published by the American Physical Society can be found at http://journals.aps.org

Specific-Heat of the Organic Metal Bis(tetrathiotetracene) Tri-Iodide from 20-K to 100-K, the Vicinity of the Metal-Nonmetal Phase-Transition

Journals published by the American Physical Society can be found at http://journals.aps.org

Modular, automated software testing environment

A software development methodology has been developed with Softool's Change and Configuration Control (CCC) environment. Fundamental to this approach is the exclusion of all development activities from the CCC data base. The contents of the CCC data base are restricted to software which has passed appropriate reviews. Development activities are performed in the host operating system account of various programmers. A set of CCC macros and VUS command files support this methodology, thereby allowing the configuration manager to transfer files between the development and configuration management environments. 3 refs

Radiological risk from thoron, a case study: The particularly radon-prone area of Bolsena, and the lesson learned

Abstract The contribution of 220 Rn is usually negligible compared to that of 222 Rn: its very short half-life makes escape from its source site within the rock very unlikely and it never has time enough to filtrate through the ground and through cracks in the floors or cellar walls to reach living quarters. This however becomes untrue if walls built with 232 Th-rich materials are present: then sizeable amounts of thoron may be detected in the closed areas bounded by those walls. This is the case for many dwellings in central Italy, and the town of Bolsena (northern Latium) is presented as a case study. A typical building of the area, entirely constructed with tuff blocks, is investigated and the annual dose rates calculated for varying distances from the wall. Thoron concentration was found to decrease with a relaxation length of 13 cm. Thoron was found to pose a significant risk. The rate of air exchange was found to produce little effect. Wall plastering acts as a filter: thoron diffuses through it but a HVL of less than 1 cm was found to prevail

30 years of European Commission Radioactivity Environmental Monitoring data bank (REMdb) – an open door to boost environmental radioactivity research

The Radioactivity Environmental Monitoring data bank (REMdb) was created in the aftermath of the Chernobyl accident (1986) by the European Commission (EC) – Directorate-General Joint Research Centre (DG JRC), sited in Ispra (Italy). Since then it has been maintained there with the aim to keep a historical record of the Chernobyl accident and to store the radioactivity monitoring data gathered through the national environmental monitoring programs of the member states (MSs). The legal basis is the Euratom Treaty, Chapter III Health and Safety, Articles 35 and 36, which clarify that MSs shall periodically communicate to the EC information on environmental radioactivity levels. By collecting and validating this information in REMdb, JRC supports the DG for Energy in its responsibilities in returning qualified information to the MSs (competent authorities and general public) on the levels of radioactive contamination of the various compartments of the environment (air, water, soil) on the European Union scale. REMdb accepts data on radionuclide concentrations from EU MSs in both environmental samples and foodstuffs from 1984 onwards. To date, the total number of data records stored in REMdb exceeds 5 million, in this way providing the scientific community with a valuable archive of environmental radioactivity topics in Europe. Records stored in REMdb are publicly accessible until 2011 through an unrestricted repository “REM data bank – Years 1984–2006” https://doi.org/10.2905/jrc-10117-10024 (De Cort et al., 2007) and “REM data bank – Years 2007–2011” https://doi.org/10.2905/de42f259-fafe-4329-9798-9d8fabb98de5 (De Cort et al., 2012). Access to data from 2012 onwards is granted only after explicit request, until the corresponding monitoring report is published. Each data record contains information describing the sampling circumstances (sampling type, begin and end time), measurement conditions (value, nuclide, apparatus, etc.), location and date of sampling, and original data reference. In this paper the scope, features and extension of REMdb are described in detail.</p