Physical and Chemical Sciences

Excerpt from the IAEA Annual Report for 1994

(Editor's note: The format of scientific notations in this electronic presentation is being standardized.)


Programme overview

The emphasis in the nuclear data subprogramme has been on: modernization of the computer related activities of the nuclear data centre; completion of the FENDL-1 nuclear data library to be used in the International Thermonuclear Experimental Reactor (ITER) project; improvement of atomic and molecular data needed for fusion plasma edge studies and for heavy element impurities in fusion plasmas; and data important for analysing activation in different areas of nuclear technology.

Improvements to the analytical capabilities of the nuclear instrumentation used by Member States were made by the upgrading of several Agency software packages. In training courses, attention continued to focus, where possible, on recent developments in nuclear instrumentation as well as on the more basic repair and maintenance aspects. The existing spare parts provision service was extended to the Africa region.

Work in the area of research reactors and accelerators focused on identifying the causes of underutilization, providing assistance in resolving relevant issues and promoting new techniques and technologies.

The focus of the chemistry subprogramme was on the production of high quality medical radioisotopes, diagnostics and therapeutic radiopharmaceuticals, in vivo diagnostic kits, radioimmunoassay (RIA)/immunoradiometric assay (IRMA) reagents and procedures. Technical support was provided for expanding applications of new radiopharmaceuticals for functional studies of the heart and brain and for SPECT imaging, including the development of radiolabelling of monoclonal antibodies for immunoscintigraphy.


NUCLEAR AND ATOMIC DATA FOR APPLICATIONS

Data centre management, co-ordination and services and manpower development in the use of nuclear and atomic data

During 1994, the Agency fulfilled more than 800 requests from scientists in 70 Member States, by dispatching 170 magnetic tapes, 510 diskettes and 1600 copies of printed material and arranging electronic data transmission to 140 users.

Further progress was made in the standardization of nuclear data software. Three of the four major nuclear data centres (in the USA, the Russian Federation and at the Agency) now use a common software package for database management and on-line services. The package was donated by the USA and recently installed in the Russian centre at Obninsk. All atomic and molecular data centres co-ordinated by the Agency are using ALADDIN as the common format for data exchange and management.

Establishment of improved nuclear data sets for fission reactor technology and safety

The first international benchmark calculation of the radioactive inventory in fission reactors for decommissioning purposes was organized. It has been shown that predictions of the amount of radioactivity produced during the service life of fission reactors inside the core and in pressure vessels can be made with sufficient accuracy. Large deficiencies in predicting the radioactivity in the concrete bio-shield were identified and the urgent need for more accurate documentation of material composition in fission reactor shields was emphasized.

Two evaluated fission yield libraries, UKFY2 (United Kingdom) and ENDF/B-6 (USA), have been finalized and released as a part of the international co-operative effort co-ordinated by the Agency. These data are important for decay heat calculations after reactor shutdown, burnup determination, safeguards, identification of source reactor accidents and nuclear transmutation studies.

Establishment of international reference libraries of nuclear and atomic data for use in fusion reactor technology

The Agency, in co-operation with several national nuclear data centres and research groups, has completed the first version of the internationally available Fusion Evaluated Nuclear Data Library, FENDL-1. This library has been selected to serve as the source of processed and tested nuclear data tailored to the requirements of the Engineering and Development Activities (EDA) of the ITER project and other fusion related development projects. It is composed of several sub-libraries for neutron-photon transport calculations and the resulting radiation effects. To facilitate the ITER EDA applications, two processed FENDL-1 sub-libraries were derived: processed multigroup and processed Monte Carlo. The BENCHMARKS sublibrary for validation of FENDL-1 has been created and tests of FENDL-1 were started. The complete FENDL-1 library was put on-line on Internet.

During 1994, recommended cross-section databases were established for the particle interchange ion-molecule reactions taking place in the fusion plasma edge, for the elastic and momentum transfer processes in ion-atom and neutral-neutral collision systems, for the particle impact induced secondary emission from fusion relevant materials and for the radiative cooling rates of helium, carbon and oxygen plasma impurities. A CRP on atomic and molecular data for plasma edge studies was successfully completed with the preparation of a compendium of critically assessed data for all important collisional processes. A similar compendium is now in preparation for the collisional processes of medium and high Z impurities in fusion plasmas. A critically evaluated collection of thermomechanical properties data for the candidate fusion reactor plasma facing materials has been assembled by an international group of experts and prepared for publication.

Development of reference nuclear databases for nuclear waste incineration, environmentally safe nuclear waste disposal and applications of intermediate energy radiations

A CRP was initiated on the establishment of an international reference data library of nuclear activation cross-sections. The goal is to develop a universal database of neutron and charged particle activation cross-sections and related decay data for nuclear and fusion technology and for environmental protection and estimates of potential radiation hazards connected with any kind of nuclear installation and technique. Of practical importance are about 2400 radionuclides which may be built up by more than 20 000 nuclear activation reactions for which the cross-sections must be measured or estimated.


NUCLEAR INSTRUMENTATION

Maintenance of nuclear instrumentation

With the aim of fostering local expertise, regional centres for specialized group training were set up in Brazil, Mexico and Colombia. These centres were established to provide training in the repair and maintenance of multichannel analysers (Brazil), radiation detectors and their analog electronics (Mexico) and nuclear instruments for medicine and gamma cameras (Colombia).

Nuclear spectroscopy

The computer code GANAAS (gamma spectrum analysis and neutron activation analysis) was upgraded by the incorporation of a new module for efficiency calculations. A new version of the SPEDAC PRO program (transfer and reformatting of spectra) was released for DOS and Windows. A new software package, Chart of the Nuclides, for Windows was completed.

Laboratory activities

In-house services and technical support continued to be offered to other parts of the Agency's Laboratory at Seibersdorf. In addition, technical assistance was provided to upgrade 12 X ray fluorescence (XRF) laboratories and extend the applications of this analytical technique for environmental pollution monitoring in the Africa region. Within the framework of a regional technical co-operation project, the Laboratory provided complete water preconcentration kits, Agency reference materials and standard samples for calibration and quality control, chemicals, parts for spectrometry systems and updated versions of QXAS (quantitative X ray analysis) software. The Laboratory also organized an intercomparison survey to assess the quality of the analytical performance of XRF laboratories in Africa. Moreover, to upgrade infrastructures for the repair and maintenance of nuclear instruments in developing Member States, in particular in the Africa region, technical support was given through expert missions, and the provision of spare parts, technical documentation, power conditioning kits, mains disturbance analysers and instruments for troubleshooting and repair.

The Laboratory was involved in: the design and construction of special instruments and training kits; a high precision current source for the calibration of dosimeters; a power supply unit for ionization chambers; a portable dosimeter; a switch-mode power supply and UNOLAB optical feedback preamplifier training kits; and a temperature control unit for a dosimetry irradiation chamber. It contributed to the development of central station software for heterogeneous early warning systems for the Middle East and Europe. Also, three types of new X ray detectors for microanalysis and portable instruments were tested.

Most methodological work carried out by the Laboratory in the field of XRF dealt with the improvement of accuracy and detectability - as well as an extension of the applicability range of the analytical technique. A simple method for the quantitative XRF analysis of in homogeneously loaded samples and a Monte Carlo simulation method for the calculation of geometrical parameters and excitation detection efficiency of a radioisotope excited XRF system were also developed. An X ray microfluorescence system with a new 10 m glass capillary and a total reflection XRF unit were used for the analysis of various environmental, geological and biological materials. It was demonstrated that XRF can be optimized to combine a broad range of applicability with very low detection limits, which are the essential features for many environmental monitoring applications, including the analysis of air particulates, water, soil and sediments. To perform routine and systematic monitoring of air pollution as well as to provide adequate training, a high volume sampler was installed in Seibersdorf.


THEORETICAL PHYSICS

Fields of research and training for research

The fields of research and training for research at the ICTP were: fundamental physics and astrophysics (high energy and particle physics, cosmology and astrophysics); condensed matter physics (solid state, materials science, surfaces and interfaces); mathematics (applicable mathematics, algebra, geometry and mathematical physics); physics and energy (plasma physics and nuclear physics); physics and the environment (geophysics, soil physics, climatology, atmosphere, aeronomy and radiopropagation, remote sensing and mathematical ecology); physics of the living state (biophysics and medical physics); and applied physics and high technology (microprocessors, communications, non-destructive evaluation, lasers and optical fibres and computer science).

Funding

The regular budget was composed of contributions from the Agency ($1 486 828), UNESCO ($373 500) and the Italian Government ($11 765 000). An extraordinary contribution from the Italian Government, amounting to $3 692 300 for 1994, was granted in April. Half of it was used to set up a reserve fund. The number of participants was higher in 1994 because of the tendency to let co-organizing institutions pay for the travel and living expenses of their own lecturers, thus becoming co-sponsors of activities. This released funds for scientists from developing countries.

For the second year, the CEC funded seven fellowships, tenable at ICTP, under its 'Go West' and 'Human Capital and Mobility' schemes. Contributions were received from the Swedish Agency for Research Co-operation with Developing Countries (SAREC), and the Governments of Japan and Kuwait to support the visits of associate members and affiliates from federated institutes. The contribution from SAREC covered the external activities as well. Spain also gave $15 000 for external activities. The funds utilized for training and research in Italian laboratories (about $190 000) came from the Consiglio Nazionale delle Ricerche, Sincrotrone Trieste S.p.a. and the Centro Informazioni Studi Esperienze. Resources for research activities in the various fields of interest, amounting to $89 000, came from the Instituto de Matematica Pura e Aplicada (Brazil), the Swiss Federal Institute of Technology, Accademia dei Lincei (Italy), the University of Trieste (Italy), the Istituto Nazionale di Geofisica (Italy), the Union radio-scientifique internationale, and the Centre nationale de la recherche scientifique (France). The Arab Fund for Economic and Social Development (Kuwait) contributed $67 300 to support visits from Arab countries.

In 1994, 80 scientists, representing 25 developing countries, worked -- with grants from the ICTP -- in 60 Italian laboratories for a total of 453.53 person/months. In addition, 5 consultants (from developed countries) and 3 short term scientists (from developing countries) visited the ICTP for a total of 8.20 person/months. The research subjects included: biophysics, condensed matter physics, earth and environmental sciences (climatology and meteorology, geophysics and soil physics), microprocessors, optical physics and lasers, medical physics, non-conventional energy and plasma physics and communications physics.

External activities

In the fields of physics and pure and applied mathematics, the Centre provided support and scientific advice to 61 scientific meetings in 25 developing countries and 3 developed. Ten Visiting Scholars were supported in their stay at 8 institutes of physics and mathematics in as many countries; so far, 9 affiliated centres have been established and, at present, 3 projects are being carried out with a view to establishing new centres. Six networks were created.

Meetings hosted

The Centre hosted eight meetings on scientific subjects. The main organizing institutions were the International Centre for Science and High Technology (ICS, Trieste, Italy); the Italian National Institute of Nuclear Physics (INFN); Sincrotrone Trieste; and the World Wildlife Fund.

Books and equipment donation programme

The Centre was able to distribute around 45 000 items of scientific literature (journals, proceedings and books) to 500 institutions in 93 developing countries. In addition to the donations directly distributed by the Centre, a large number of donations of complete sets of back issues of journals were shipped directly by the donors to institutions in developing countries.

Awards

The 1994 Dirac Medal of the ICTP was awarded to F. Wilczeck (Institute for Advanced Study, Princeton, USA) for his contributions to the development of theoretical physics. The 1994 ICTP Prize in the fields of mathematics, nuclear physics, plasma physics and other field of physics, in honour of Sir Michael Atiyah, was awarded to Chao-Jiang Xu from Wuhan University, China, for his contributions to non-linear sub-elliptic problems, symbolic calculus of sub-elliptic operators and diffraction problems for non-linear waves.

Preprints and internal reports

In 1994, 410 preprints and internal reports were issued.


UTILIZATION OF RESEARCH REACTORS AND PARTICLE ACCELERATORS

Optimization research reactor operation, utilization and management

Technical support continued to be provided to enhance the level of utilization of research reactors in developing Member States. A Technical Committee meeting was organized to encourage regional co-operation in this field.

The software of the Research Reactor Database has been adapted for use with PCs. The data can now be used for generating the following publications: Reference Data Series No. 3: Nuclear Research Reactors in the World and the Directory of Nuclear Research Reactors.

Laboratory activities

In order to enable the Agency's Laboratory at Seibersdorf to provide advanced analytical services in support of Agency programmes, it was decided to construct and install a beam line analytical facility at an existing accelerator in a nearby Member State. The beam line including proton induced X ray emission (PIXE) chamber, vacuum system, energy dispersive X ray spectrometer with Si(Li) detectors and a germanium detector was inaugurated at the EN Tandem Van de Graaff of the Laboratory for Nuclear Microanalysis at the Ruder Boskovic Institute, in Zagreb, Croatia. The host institution offered the Agency three days per month beam time on a cost-free basis as well as supporting facilities, such as a sample preparation laboratory and a mechanical/electronic workshop. Following the installation of the beam line, the Agency's Laboratory is now able to provide advanced analytical services and training in PIXE, proton induced gamma emission (PIGE), Rutherford backscattering spectroscopy (RBS) and nuclear reaction analysis (NRA).


CHEMISTRY

Production of radiopharmaceuticals of 99Tcm and 99 Tcm generators from low specific activity 99Mo

The last Research Co-ordination meeting was held for a CRP on alternative technologies for 99Tcm generators based on low temperature sublimation and gel elution. The results will be published in an IAEA-TECDOC. It was demonstrated that gel and sublimation technologies are suitable for the preparation of high quality 99Tcm generators for use in nuclear medicine. The initial tests were carried out in China through a technical co-operation model project. Several other countries operating research reactors are now considering the adoption, partially or in full, of sublimation or gel technology in place of the fission 99Mo based generator.

A CRP on the preparation and evaluation of bulk reagents and ligands for radiopharmaceutical formulation kits was completed and the last Research Co-ordination meeting was held. Several new radiopharmaceuticals for the brain, heart and kidneys were assessed and the technology on their preparation was transferred.

Biomolecule labelling techniques

The initial results achieved under a CRP on the optimization of the production and quality control of radiotherapeutic radionuclides were reviewed at a Research Co-ordination meeting. It has become clear that research reactors available in developing Member States can be used for the production of beta emitters such as 186Re, 153Sm and 166Ho. Bone seeking radiopharmaceuticals labelled with these nuclides were also investigated with the aim of developing effective radiopharmaceuticals for the relief of bone pain resulting from metastases from breast, prostate and lung cancer. Tests on animals have been positive.

Results achieved in a CRP on labelling, quality control and clinical evaluation of monoclonal antibodies for scintigraphy were reviewed at a Research Co-ordination meeting. Labelling and quality control protocols and labelling of the anti-CEA monoclonal antibody were investigated, including immunoreactivity measurements. Labelled antibodies were studied in animals possessing sterile inflammations as well as biodistribution in normal mice. It was concluded that the participants in the CRP are now proficient in labelling monoclonal antibodies with 99Tcm for immunoscintigraphy studies.

Applications of nuclear generated heat in the chemical industry

A demonstration of the possibility of applying heat at temperatures of 550 degrees to 950 degrees Celsius from high temperature gas cooled reactors directly to endothermic chemical processes has been planned with the Japanese High Temperature Engineering Test Reactor (HTTR). Chemical processes such as hydrogen and/or methanol production using methods such as steam reforming, thermochemical water splitting and high temperature electrolysis will be examined.

Laboratory activities

Development work at the Agency's Laboratory at Seibersdorf has focused on reference materials for large scale population monitoring for mercury and methylmercury through hair analysis and materials for air pollution monitoring. A previously developed lichen material has been certified for 30 trace metals. This first Analytical Quality Control Service (AQCS) in this field will be complemented by a more highly polluted lichen and several air particulate materials. Experimental work demonstrating feasibility has been completed at the laboratory and a first set of air particulate matter samples is being evaluated.

Two new reference materials for radiometric measurements (IAEA-373 and IAEA-375) have been certified. The soil sample IAEA-375 is the first natural material worldwide certified for the content of 129I. An intercomparison run with 237 participating laboratories is in progress on the determination of natural and artificial radionuclides in two soil samples (IAEA-326 and IAEA-327).

An Advisory Group on AQCS has identified additional requirements for a more effective service. The major points include ISO-9000 registration of the AQCS programme, expansion to conduct more laboratory performance evaluations and direct assistance to Member State laboratories to achieve accreditation quality performance through collaborative development, technology transfer and training. A pilot project has been started with GEMS/Food-EURO in co-operation with FAO.