Long-term Storage Facility Research Articles

A software tool for the input and management of phenotypic data using personal digital assistants and other mobile devices.

BackgroundPlant breeding and genetics demand fast, exact and reproducible phenotyping. Efficient statistical evaluation of phenotyping data requires standardised data storage ensuring long-term data availability while maintaining intellectual property rights. This is state of the art at phenomics centres, which, however, are unavailable for most scientists. For them we developed a simple and cost-efficient system, the Phenotyper, which employs mobile devices or personal digital assistants (PDA) for on-site data entry and open-source software for data management.ResultsA graphical user interface (GUI) on a PDA replaces paper-based form sheet and data entry on a desktop. The user can define his phenotyping schemes in a web tool without in-depth knowledge of the system and thus adjust it more easily to new research aspects than in a classical laboratory information management system (LIMS). In the Phenotyper, schemes are built from controlled vocabulary gained from published ontologies. Vocabulary and schemes are stored in a database that also manages the user access. From the web page, schemes are downloaded as extended markup language (XML) files for the transfer to the PDA and the exchange between users. On the PDA, the GUI displays the schemes and stores data in comma separated value format and XML format. After manual quality control, data are uploaded via a web page to an independently hosted results database, in which data are stored in an entity-attribute-value structure to provide maximum flexibility. Datasets are linked to the original and curated data files stored on a file server. The ownership stamp, project affiliation and date stamp of a dataset are used to regulate data access, which is restricted to data belonging to the user or to his projects and data, for which the embargo period has ended. By export of standardised ASCII reports to long-term data storage facility, long-term accessibility allows searching, citing and use of raw data beyond the lifetime of the database. The Phenotyper is available to the scientific community for use and further development.ConclusionsThe Phenotyper provides a well-structured, but flexible data acquisition and management structure for mobile on-site measurements for efficient evaluation and shared use of data.Electronic supplementary materialThe online version of this article (doi:10.1186/s13007-015-0069-3) contains supplementary material, which is available to authorized users.

Landscape Engineering and Organizational Complexity among Late Prehistoric Bison Hunters of the Northwestern Plains

Studies of hunter-gatherer sociopolitical organization consistently exclude terrestrial big-game hunters—pedestrian bison hunters, in particular—from discussions of emerging complexity. To an important extent, this exclusion stems both from the ethology of bison and its consequences for mobile hunters and from the character of their archaeological record, which lacks conventional indicators of organizational complexity such as high-status burials and long-term storage facilities. However, this record exhibits stone architecture of monumental proportions. We argue that evidence of emerging sociopolitical complexity is embodied in the hunters’ ability to (1) invest extensively on landscape engineering to amass communal bison wealth for consumption, storage, and exchange, and (2) produce and reproduce ritual wealth among individuals and restricted sectors of the group. Through a multiscalar research design that integrates thousands of surface stone features with data recovered from kill site excavation, ethn...

Nitrogen vapor shipment of vitrified oocytes: time for caution

Oocyte cryopreservation for fertility preservation, in both medical and elective situations, has significantly increased as freezing technology has improved. Slow freezing techniques demonstrated ∼ 50-80% survival of mature oocytes, however vitrification with ∼ 97% survival has become the preferred method for oocyte cryopreservation around the world. Our work investigated the effect of transporting cryopreserved oocytes to and from a long-term storage facility. Our findings demonstrate that extra caution should be practiced for vitrified oocytes, especially when handling and transferring between shipping and long-term cryopreservation storage containers.

Solutions for scientific problems related with temperature SNF storage regime

The dry long-term storage facility (SFSF-2) is a chamber-type structure formed by cast-in-place steel-concrete walls, top and bottom floorings separated with lateral steel-concrete partitions to several chambers. The main task in the creation of the storage facility is to provide an efficient natural air circulation circuit. A broad scope of experimental and computation researches has been carried out to solve that scientific task. Special test benches have been designed to simulate thermal processes, air motion in the circuit of natural circulation and to verify, based on the research outcomes, computer codes ‘Fluent’ and ‘Conrad’ in terms of computation of temperature distribution within the facility’s components. Computation outcomes of the RBMMK-1000 Fuel Assemblies temperature conditions within casks placed in chamber-type storage facility wells in case of uniform loading of the wells within the dry storage facility chamber in two tiers of casks with maximally possible decay heat capacity have shown that maximal fuel cladding temperatures are lower than those set by input requirements.

The investigation of Negative Horizontal Ventilation for Long-term Storage of Sweetpotatoes

North Carolina is the largest producer of sweetpotatoes in the United States with an annual production of nearly 320 million kg (NCDACS, 2007). Under optimum storage conditions, sweetpotatoes may be held in marketable condition for longer than 10 months. This allows for orderly marketing throughout the year. In the last 15 years, several hundred long-term storage facilities have been built employing a novel air movement system now termed negative horizontal ventilation (NHV). Most of these facilities are located in North Carolina and other sweetpotato producing areas of the southeastern United States but some have been built in Asia, the Philippines, New Zealand, Canada, and Uruguay. This technology is especially suitable for the large commercial sweetpotato storage facilities now common in the industry. Pack-out percentages (defined as the salable weight removed from storage compared to the salable weight entering) for 8 to 10 month storage utilizing the NHV system average 90%. This compares to 60% to 70% for previous common storage methods and facilities. This article summarizes some of the efforts towards design optimization of these facilities for the curing and storing of sweetpotatoes

Burnup studies of spent fuels of varying types and enrichment

This paper describes the results of fuel burnup measurements, made over a period of several years on discharged fuel from nuclear power plant and research reactor. The measured and calculated burnup of different spent fuel types, viz.: Natural uranium CANDU fuel bundles; 10.5% enriched booster rods; 20% enriched MTR fuel elements have been presented. High-resolution gamma spectrometry, using 137Cs and 134Cs burnup monitors was employed in different reactors to estimate the amount of 235U depletion in the respective fuel. The experimental data was compared with those of calculations to optimize fuel-scheduling programme. The burnup data is useful for assessment of fuel performance in the core and resolving design issues related to long-term storage facilities. It has been observed that the gamma spectrometry is very effective in identifying exact position of individual booster bundles inside the discharged booster assemblies, which is useful in safeguard applications. It is concluded that the distribution of measured isotopic activity ratios of 134Cs/ 137Cs along the height of the spent fuel gives accurate estimate of the axial neutron flux profiles in the core. The activity ratio technique therefore provides a useful method to determine flux peaking factors at the particular locations of the fuel assemblies in the reactor.

The October 2005 Georgian Bay, Canada, Earthquake Sequence: Mafic Dykes and Their Role in the Mechanical Heterogeneity of Precambrian Crust

On 20 October 2005 at 21:16 UTC, a moderate earthquake (mN 4.3) occurred in an area of low seismicity within Georgian Bay, approximately 12 km north of Thornbury, Ontario (44.67 N, 80.46 W). Despite its moderate magnitude, it was exceptionally well recorded and is of particular interest because of its location 90 km from a proposed long-term storage facility for low- and medium-level nuclear waste. No damage was reported, but ground shaking was felt to a distance of 100 km. Within 24 hours after the mainshock, four portable seismograph systems were in- stalled in the epicentral region. In total, eight events were recorded over a 4-day period, including a foreshock and six aftershocks. The unusually rich dataset from this moderate earthquake sequence enabled robust determination of hypocentral pa- rameters, including well-constrained focal depths for most events. For the mainshock, we estimated a seismic moment of M0 4.5 10 14 N m and corner frequency of 3.7 Hz, based on a spectral fit using Brune's source model. Least-squares waveform inversion of P and S phases yielded a double-couple focal mechanism with a reverse- sense of slip and northwest-striking nodal planes. The reverse mechanism and mid- crustal focal depths (10-12 km) are characteristic, in general, of more abundant seismicity located 200 km northeast of this event in the western Quebec seismic zone. These parameters differ, however, from shallow (2-6 km) earthquakes, with predominantly strike-slip mechanisms, observed near Lake Erie 200 km to the south. We attribute this north-south change in rupture mechanism to variations in crustal stress induced by postglacial isostatic rebound. Aeromagnetic data in and around the epicentral region reveal prominent northwest-striking lineations caused by Precam- brian mafic dykes. Under midcrustal conditions, the dyke material is mechanically stronger than generally more felsic upper-crustal host rocks. We propose that where large dykes are favorably oriented with respect to the stress field, they may strongly influence the locations of intraplate earthquake rupture in Shield regions.

Durability design of heated concrete structures. Methodology and application to long-term interim storage

The operation of civil engineering structures subjected to thermal and mechanical loading has led the CEA to examine temperature-dependent variations in the concrete properties and the processes affecting the durability of these structures. A new approach has been undertaken to specify the thermal, hydric and mechanical history of these structures. This technical approach is based on three areas of research: material characterization, modelling to identify weaknesses in the structure and validation by experimental tests on heavily instrumented structures subjected to representative loads. The procedure adopted for long-term interim storage facilities [1, 2] can also be applied to other domains.

Transmutation of actinides in power reactors

Power reactors can be used for partial short-term transmutation of radwaste. This transmutation is beneficial in terms of subsequent storage conditions for spent fuel in long-term storage facilities. CANDU-type reactors can transmute the main minor actinides from two or three reactors of the VVER-1000 type. A VVER-1000-type reactor can operate in a self-service mode with transmutation of its own actinides.

Evaluation of Frozen Thawed Embryo Outcome After Transportation to a Long-Term Storage Facility Versus In-House Storage Facility

Objective: The objective of this study was to evaluate the outcomes of frozen embryo transfers (FET) on the embryos that were cryopreserved and transported to a long-term storage facility and then brought back later for FET cycles as compared to the outcomes of embryos that were cryopreserved and thawed in house. This comparison was carried out as further quality control of our procedures for remote site embryo banking. Design: Retrospective comparative study. Materials and Methods: All the embryos that were used for this study were cryopreserved at blastocyst stage and the protocol for freezing and thaw were a modified protocol as described by us earlier (ASRM 2004, abstract # P-58). Frozen embryos were stored in liquid nitrogen (LN2) and monitored. For transportation to our chosen remote site cryo laboratory (Reprotech Ltd, Roseville, MN) dry shippers were used that were previously saturated with LN2 and embryos were shipped in dry shipper by overnight courier. For QC purpose these shippers contain a cryoguard indicator vial. Vial content is green as long as temperature inside the shipper is -120oC and if for some reason temperature falls, it will turn red. These shippers are good to maintain the temperature for at least a week and they are checked intermittently for any leaks or deviations from the required storage temperature. Results: We have analyzed 18 FET cycles that were cryopreserved at our facility and sent for long-term storage to use later for FET. A total of 63 blastocysts thawed and 47 blastocysts were transferred from September 2003 until March 2005. Out of 18 FET, 12 cycles had a positive HCG test and eight are clinically pregnant (44%). Clinical pregnancy is defined as the presence of fetal heart beat by ultrasound. Our in house clinical pregnancy rate for FET during the period evaluated was 40%. Conclusion: Based on these data we conclude that there is no difference in clinical pregnancy rate for the embryos that were sent for long-term storage versus in house storage, if a strict QC is maintained throughout storage and transportation. Sending embryos to a cryobank for the storage could be an attractive option for ART centers where space constraint is a problem. Remote storage out sources the daily inventory and LN2 monitoring work. A significant liability in storing these preimplantation embryos for long-term are also outsourced. INTRODUCTION Long-term storage of embryos generated by ART laboratories in a remote cryobank could be an attractive option for many ART laboratories where space constraint is a problem. It has some other advantages as well because it can significantly eliminate the inventory maintenance and continuous liquid nitrogen monitoring. We have evaluated this option of sending the embryos to a remote cryobank keeping in consideration the stringent quality control procedures practiced during these transfers and storage. We also compared the clinical pregnancy rate obtained after transferring these embryos in frozen embryo transfer (FET) cycles after bringing them back to our laboratory with our ongoing clinical pregnancy rate in FET cycles of those embryos that remained in our laboratory. MATERIALS AND METHODS All the embryos that were used for this study were cryopreserved at the blastocyst stage and the protocol for freezing and thaw were modified protocol as described by us earlier (Srivastava et al, 2004, Veeck et al, 2004). Only expanding, expanded, hatching or hatched blastocysts with well-defined inner cell mass and a cohesive trophectoderm were frozen on day 5, 6 and 7. Frozen embryos were stored in liquid nitrogen (LN2) and monitored. For transportation to our chosen remote site cryo laboratory (Reprotech Ltd, Roseville, MN) dry shippers were used that were previously saturated with LN2 and embryos were shipped in dry shipper by overnight courier. For QC purpose these shippers contain a cryoguard indicator vial. The vial content is green as long as the temperature inside the shipper is less than -120oC and if for some reason the temperature rises, it will turn red. These shippers are good to maintain the temperature for at least a week and they are checked intermittently for any leaks or deviations from the required storage temperature. TABLE: Comparison of clinical pregnancy rate between remotely stored embryos and in-house stored embryos Total FET cycles analyzed when frozen embryos were sent earlier to cryobank and later brought back to our laboratory: (From 09/03 to 02/05): 18 Total blastocysts thawed: 63 Total blastocysts transferred: 47 Number of FET cycles with positive HCG: 12 Number of cycles with clinical pregnancy: 8 Clinical pregnancy rate: 44%

German assistance for the dismantling of nuclear submarines in Russia

Abstract On October 9, 2003, the German Ministry of Economics and Labor signed an agreement with the Russian Federation's former Ministry of Atomic Energy for support in eliminating the nuclear weapons that the Russian Federation has pledged to reduce through the dismantlement of decommissioned nuclear submarines. This treaty, which is binding under international law, implements the Global Partnership against the Spread of Weapons and Materials of Mass Destruction as agreed to at the G8 Summit in Kananaskis in 2002. The core element of the German-Russian project is the creation of a long-term interim storage facility for 120 nuclear submarine reactor compartments near Murmansk in northwestern Russia and the preparation of the reactor compartments for interim storage. This technically demanding project, which began not without some problems, has developed in a positive manner since the end of 2003. The provisions in the treaty and its supplementary documents, which were internationally publicized, have generally proven to be successful.

INTO THE NEW MILLENNIUM: CONSERVATION INPUT FOR FOUR TWENTY-FIRST CENTURY ARTS BUILDINGS

The Conservation Department of the National Gallery of Victoria in Melbourne, Australia, contributed to four new building projects: an offsite long-term storage facility with temporary conservation facilities; a temporary display for approximately three years in a newly renovated nineteenth-century building; a new building with 21 galleries devoted exclusively to Australian art; and the complete renovation of a 1967 building to turn it into a 30-gallery building dedicated to international art. Preventive conservation principles were applied to all four buildings and the author presents a synopsis of his experience of these projects.

Creep behavior of Bure clayey rock

Clayey rock may be the host medium for a French long-term nuclear-waste storage facility. To gain better understanding of the delayed behavior of this potential host rock, we conducted a testing program that focused on creep tests. Fourteen tests were conducted: short-term multi-step creep tests (six at ambient temperature, four at T=80 °C and four on damaged samples); and four long-term mono-step creep tests (in which a constant load is applied for nearly 2 years). Experimental results are displayed and discussed.

Hunter–gatherer mobility, storage, and houses in a marginal environment: an example from the mid-Holocene of Wyoming

Important for considerations of hunter–gatherer mobility is delineating what the presence of house remains in the archaeological record from an environmentally marginal area represents in terms of mobility patterns—especially the duration of site occupation and the stability of these patterns from year to year. Some insights into the archaeological record concerning houses and mobility in a marginal environment can be obtained by investigating several lines of evidence: the design and substantialness of the represented structures; the density and diversity of the recovered remains; the distribution of the remains and whether refuse cleaning was practiced; the kinds, relative efficiency, and quantity of resources exploited; the presence or absence of long-term storage facilities; and the possibility of site reuse. The excavation of 41 pit structures or housepits at 21 sites in the Wyoming and Big Horn basins of Wyoming dating to the mid-Holocene provides an excellent opportunity to study hunter–gatherer mobility and houses in a marginal, low carrying capacity environment. The Wyoming housepits appear to represent short-term occupations of residentially mobile groups, who constructed these structures in anticipation of repeated visits and reuse over a period of years—exemplifying stable land use patterns.

Long-Lived-Radionuclide Transmutation Scenarios

The results of multigroup calculations of continuous irradiation of Np, Am, and Cm in VVER-1000, PHWR-880, Superphoenix-1200, BREST-1000, and ELYaU-800 reactors are used to compare transmutation efficiency. The sources of continuous replenishment for the transmuters were Np, Am, and Cm extracted after a 3-yr holding period from the VVER and Superphoenix spent fuel. It is shown that the most effective transmuter is a subcritical liquid-fuel ELYaU system with an average thermal-neutron flux in the blanket 2·10 15 sec ‐1 ·cm ‐2 . For solid-fuel reactors, the continuous-irradiation model makes it possible to describe approximately the multiple transmutation regime. In the foreseeable future, one-time transmutation of Np, Am, and Cm in a solid-fuel reactor followed by storage in a long-term storage facility is feasible. The results of different computational variants for such regimes show that for transmutation in 10 yr in PHWR the radiotoxicity of Np, Am, and Cm accumulated in long-term storage reaches an equilibrium in no longer than 100 yr. Nuclear reactors used for transmutation actually become a kind of repository for sources of long-lived radionuclides. There is no need to prove that the content of the most dangerous (for humans) radionuclides in transmutation reactors today is incomparably more dangerous than storage in specially equipped enclosures at low temperatures and pressures. However, these considerations, in our opinion, should not be taken as a justification for considering research on transmutation as unpromising. The specialists who are proposing nuclear power as a large-scale and long-term method for producing energy are bound to develop and substantiate an effective method for eliminating harmful wastes produced as a result of such production. It is not ruled out that the practical application of transmutation will be needed only in the distant future, possibly in the period when nuclear power plants will not longer be operating. But, means must be expended even now on investigations which will make it possible to show the actual possibility of annihilating long-lived radionuclides. Otherwise, society may completely reject the use of atomic energy. In this paper, we present the results of investigations of the effectiveness of transmutation of long-lived radionuclides in reactor systems operating under closed fuel cycle conditions. The technological aspects of the problem, such as the arrangement of radionuclides in the reactor core, the influence of the radionuclides on the degree of burnup of the fuel, and the reactivity coefficients, were not studied. The results of such comparative investigations were first published in [1]. In th e present paper, multigroup calculations of the burnup and fission rate, i.e., the elimination of Np, Am, Cm, and their daughter nuclei during irradiation in different neutron fluxes and spectra, are presented. In addition, the latest data on the radiation safety standards are used [2] and the list of possible transmutation reactors and Np, Am, and Cm sources is expanded. The combined approach to handling long-lived radionuclides using transmutation and long-term storage is analyzed. The results obtained made it possible to choose the optimal, in our opinion, scenario for transmutation of Np, Am, and Cm.

Fodder Beet and Sugarbeet Breeding , Germplasm Collection, and Utilization in Lithuania

Fodder beet and sugarbeet (Beta vulgaris L.) breeding programs were initiated in Lithuania in 1933. Two multi­ germ and one monogerm sugarbeet varieties were released between 1947 and 1971. Fodder beet breeding was contin­ ued until 1996, with the development of eight varieties. Research on fodder beet and sugarbeet genetic resources in Lithuania was started in 1994, under control of the In­ dustrial Crop Group. All genebank activities relating to sugarbeet and fodder beet genetic resources are based at the Lithuanian Institute of Agriculture. Currently seven accessions (mostly old Lithuanian varieties) are kept in long-term storage facilities. Other accessions are in work­ ing collections and seed is available for exchange with other genebanks.

A moisture probe using neutron moderation for PuO/sub 2/ canister inspection

We have been developing a sensor to quickly and non-destructively measure the moisture content of canisters containing PuO/sub 2/. These canisters will be retained in long-term storage facilities and, for stability reasons, must have moisture contents <0.5 wt%. The technique relies on the moderation of neutrons emitted by a radioisotopic source (Cf-252) to determine the hydrogen content of the material. Modeling was used to help optimize the sensor design and to predict the sensitivity to moisture content. A benchmodel was first constructed and tested at SAIC with simulated PuO/sub 2/ using Fe/sub 3/O/sub 4/ and B/sub 4/C; moisture was simulated with nylon rods. The benchmodel was also tested at Los Alamos National Laboratory (LANL) using actual PuO/sub 2/-filled canisters modified to accept polyethylene rods to simulate moisture. The results indicated that the detection limit (one statistical standard deviation) for a 10 minute inspection was less than 1.2 g of water, or 0.04 wt%, in 3 kg of PuO/sub 2/. A prototype system was recently constructed for testing a variety of PuO/sub 2/ samples with various material matrices. Here we present the calculations, sensor designs, tests, test results, and discuss future plans.

Twenty Years of Experience in Spent Fuel Shipment from German Nuclear Power Plants—A View of the Competent Authority

A survey of the transport of spent fuel in and from Germany during the last 20 years is presented. The spent fuel is now transported from the German nuclear power facilities to the reprocessing plants in France and the United Kingdom. In the past, there were also shipments to the former reprocessing plant WAK Karlsruhe (Germany), to the long-term storage facility CLAB (Sweden) and also from the former German Democratic Republic to the USSR. The transport of the spent fuel is carried out in specially built flasks requiring an extensive quality assurance programme. Due to the heavy weight of these packages, the shipments are mostly carried out by rail, but also by road and sea. An overview is given of the following matters: (i) quantities of spent fuel transport, (ii) organisation of transport, (iii) licensing matters, and (iv) reported incidents. In addition, an analysis is included of the radiation exposure for normal conditions of transport, especially of the transport workers. Difficulties and hindrances during transport are also reported.

Mobile fuel cell development at Siemens

Low temperature fuel cells with hydrogen and oxygen as the reactants are well-suited as a power source of an air-independent propulsion system in a submarine. Their higher energy density, noisless operation, absence of polluting gases and low waste heat as a consequence of the favourable efficiency are advantageous compared with convential systems. PEM fuel cells will be preferred for their overload capacity, low power degradation, long lifetime and the possibility to operate the fuel cell at different temperatures. Due to the fact that the PEM-FC can also be operated with CO 2-containing reactants and because of their considerable potential for increasing power, it is possible to construct energy storage systems with H 2/air fuel cells which can be used in electric cars or long-term storage facilities for regenerative energy systems. Depending on the storage capacity required, it is possible to obtain energy densities which clearly surpass those of high temperature electrochemical batteries like sodium/sulfur. Results of the current development will be reported and the application potential will be discussed.

Airport-Passenger Parking Design

Despite standard procedures for estimating the quantity of parking space for airports, great difficulties persist at many terminals. These principally concern the amount of space available for the short-term parking of vehicles used in the pickup and delivery (PUD) of passengers. The problem is that of determining the right quality or mix of parking facilities. A need is identified for a different kind of facility: space for vehicles remaining for 30 minutes or less during PUD activities. This represents an intermediate kind of facility between curb space, which is most useful for very rapid PUD by taxis, courtesy cars, and the like, and the standard short- and long-term storage facilities. When this kind of space is not available close to a terminal, drivers will be forced to jam the curbside. A way to estimate the amount of PUD space desirable for airports is proposed. The practical examples of Boston and Los Angeles are discussed.