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Sample records for iodine-125 seeds sealing

  1. Autoradiography for iodine-125 seeds

    International Nuclear Information System (INIS)

    Alberti, W.; Divoux, S.; Pothmann, B.; Tabor, P.; Hermann, K.P.; Harder, D.

    1993-01-01

    To study the interior design of model 6702 and 6711 iodine-125 seeds, contact autoradiographs were performed using mammography film. Improved resolution was obtained using a pin-hole camera with a hole of 0.1 mm x 0.1 mm. With these techniques, qualitative determination of the relative activity distribution within each seed was possible. The number of the activated resin spheres and the positions of the centers of these spheres can be exactly determined. A model calculation shows that variations in the arrangement of the activated spheres within a seed have a moderate influence on the dose distribution at source distances below 10 mm. Knowing the exact source configuration may be useful when comparing dose calculations with measured data for model 6702 125 I seeds which are currently employed in ophthalmic plaque and implant therapy of other tumors. 16 refs., 5 figs., 2 tabs

  2. Iodine-125 seeds for cancer treatment

    Energy Technology Data Exchange (ETDEWEB)

    Rostelato, Maria E.C.M.; Zeituni, Carlos A.; Feher, Anselmo; Moura, Joao A.; Moura, Eduardo S.; Nagatomi, Helio R.; Manzoli, Jose E.; Souza, Carla D., E-mail: elisaros@ipen.b, E-mail: czeituni@pobox.co, E-mail: afeher@ipen.b, E-mail: jmoura31@yahoo.com.b, E-mail: esmoura@ipen.b, E-mail: hrnagato@ipen.b, E-mail: jemanzoli@ipen.b, E-mail: cdsouza@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Karam, Dib, E-mail: dib.karan@usp.b [Universidade de Sao Paulo (USP), SP (Brazil). Escola de Artes, Ciencias e Humanidades

    2009-07-01

    In Brazil, cancer has become one of the major public health problems. An estimate by the Health Ministry showed that 466,430 people had the disease in the country in 2008. The prostate cancer is the second largest death cause among men. The National Institute of Cancer estimated the occurrence of 50,000 new cases for 2009. Some of these patients are treated with Brachytherapy, using Iodine-125 seeds. By this technique, small seeds with Iodine-125, a radioactive material, are implanted in the prostate. The advantages of radioactive seed implants are the preservation of healthy tissues and organs near the prostate, besides the low rate of impotence and urinary incontinence. The Energy and Nuclear Research Institute - IPEN, which belongs to the Nuclear Energy National Commission - CNEN, established a program for the development of the technique and production of Iodine-125 seeds in Brazil. The estimate for the 125-Iodine seeds demand is of 8,000 seeds/month and the laboratory to be implanted will need this production capacity. The purpose of this paper is to explain the project status and show some data about the seeds used in the country. The project will be divided in two phases: technological development of a prototype and a laboratory implementation for the seeds production. (author)

  3. Quality Assurance Procedure Development in Iodine-125 Seeds Production

    International Nuclear Information System (INIS)

    Moura, J.A.; Moura, E.S.; Sprenger, F.E.

    2009-01-01

    Brachytherapy using Iodine-125 seeds has been used in prostate cancer treatment. In the quality control routine during seed production, leak tests are made to detect any leakage of radioactive material from inside the titanium shield. Leak tests are made according to the International Standard Organization- Radiation protection - sealed radioactive sources - ISO 9978 standard, and require liquid transfer between recipients. If any leakage happens, there will be contamination of the liquid and tubing. This study aims to establish decontamination routines for tubing, allowing its repeated use, in the automated assay process

  4. Automation system for quality control in manufacture of iodine-125 sealed sources used in brachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    Somessari, Samir L.; Feher, Anselmo; Sprenger, Francisco E.; Rostellato, Maria E.C.M.; Moura, Joao A.; Costa, Osvaldo L.; Calvo, Wilson A.P., E-mail: somessar@ipen.b, E-mail: afeher@ipen.b, E-mail: sprenger@ipen.b, E-mail: elisaros@ipen.b, E-mail: olcosta@ipen.b, E-mail: wapcalvo@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2011-07-01

    The objective of this work is to develop an automation system for Quality Control in the production of Iodine-125 sealed sources, after undergoing the process of laser beam welding. These sources, also known as Iodine-125 seeds are used, successfully, in the treatment of cancer by brachytherapy, with low-dose rates. Each small seed is composed of a welded titanium capsule with 0.8 mm diameter and 4.5 mm in length, containing Iodine-125 adsorbed on an internal silver wire. The seeds are implanted in the human prostate to irradiate the tumor and treat the cancerous cells. The technology to automate the quality control system in the manufacture of Iodine-125 seeds consists in developing and associate mechanical parts, electronic components and pneumatic circuits to control machines and processes. The automation technology for Iodine-125 seed production developed in this work employs programmable logic controller, step motors, drivers of control, electrical-electronic interfaces, photoelectric sensors, interfaces of communication and software development. Industrial automation plays an important role in the production of Iodine-125 seeds, with higher productivity and high standard of quality, facilitating the implementation and operation of processes with good manufacturing practices. Nowadays, the Radiation Technology Center at IPEN-CNEN/SP imports and distributes 36,000 Iodine-125 seeds per year for clinics and hospitals in the whole country. However, the Brazilian potential market is of 8,000 Iodine-125 seeds per month. Therefore, the local production of these radioactive seeds has become a priority for the Institute, aiming to reduce the price and increase the supply to the population in Brazil. (author)

  5. Automation system for quality control in manufacture of iodine-125 sealed sources used in brachytherapy

    International Nuclear Information System (INIS)

    Somessari, Samir L.; Feher, Anselmo; Sprenger, Francisco E.; Rostellato, Maria E.C.M.; Moura, Joao A.; Costa, Osvaldo L.; Calvo, Wilson A.P.

    2011-01-01

    The objective of this work is to develop an automation system for Quality Control in the production of Iodine-125 sealed sources, after undergoing the process of laser beam welding. These sources, also known as Iodine-125 seeds are used, successfully, in the treatment of cancer by brachytherapy, with low-dose rates. Each small seed is composed of a welded titanium capsule with 0.8 mm diameter and 4.5 mm in length, containing Iodine-125 adsorbed on an internal silver wire. The seeds are implanted in the human prostate to irradiate the tumor and treat the cancerous cells. The technology to automate the quality control system in the manufacture of Iodine-125 seeds consists in developing and associate mechanical parts, electronic components and pneumatic circuits to control machines and processes. The automation technology for Iodine-125 seed production developed in this work employs programmable logic controller, step motors, drivers of control, electrical-electronic interfaces, photoelectric sensors, interfaces of communication and software development. Industrial automation plays an important role in the production of Iodine-125 seeds, with higher productivity and high standard of quality, facilitating the implementation and operation of processes with good manufacturing practices. Nowadays, the Radiation Technology Center at IPEN-CNEN/SP imports and distributes 36,000 Iodine-125 seeds per year for clinics and hospitals in the whole country. However, the Brazilian potential market is of 8,000 Iodine-125 seeds per month. Therefore, the local production of these radioactive seeds has become a priority for the Institute, aiming to reduce the price and increase the supply to the population in Brazil. (author)

  6. Brazilian demand for Iodine-125 seeds in cancer treatment after a decade of medical procedures

    Energy Technology Data Exchange (ETDEWEB)

    Costa, Osvaldo L. da; Souza, Daiane C.B. de; Feher, Anselmo; Moura, João A.; Souza, Carla D.; Oliveira, Henrique B. de; Peleiras Junior, Fernando S.; Zeituni, CArlos A.; Rostelaro, Maria E.C.M., E-mail: olcosta@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2017-07-01

    Iodine-125 and palladium-103 are radionuclides employed to made medical devices used in cancer treatment known as brachytherapy seeds. These radioactive sealed sources are applied in brain and ophthalmic cancer as a temporary implant to irradiate the tumor and in permanent implants to prostatic cancer. Brazilian Nuclear Energy Commission (CNEN) has the monopoly in Brazil of iodine-125 brachytherapy seeds distribution which is executed for Nuclear and Energy Research Institute (IPEN-CNEN/SP). Along a decade of use in Brazil more than 240 thousand seeds were implanted in patients or used to treat cancer tumors. In this article the Brazilian demand for iodine-125 brachytherapy seeds is analyzed. The demand behavior along a decade of using loose, strand, ophthalmic and brain brachytherapy seeds are shown. The annual quantity of seeds demanded by Brazil has dropped since 2012. The loose seeds which represented until 30% from total brachytherapy seeds used in Brazil decreased to less than 3%. The brain brachytherapy seeds had low demand along the decade and presented zero demand in several years. Concurrent treatment techniques are listed and main trends are discussed. The influence of Brazilian economic crisis and the demand behavior of the main hospitals and clinics that use Iodine-125 brachytherapy are shown. (author)

  7. Development of an encapsulation method using plasma arc welding to produce iodine-125 seeds for brachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    Feher, Anselmo; Calvo, Wilson A.P.; Rostelato, Maria E.C.M.; Zeituni, Carlos A.; Somessari, Samir L.; Costa, Osvaldo L.; Moura, Joao A.; Moura, Eduardo S.; Souza, Carla D.; Rela, Paulo R., E-mail: afeher@ipen.b, E-mail: wapcalvo@ipen.b, E-mail: elisaros@ipen.b, E-mail: somessar@ipen.b, E-mail: olcosta@ipen.b, E-mail: esmoura@ipen.b, E-mail: cdsouza@ipen.b, E-mail: prela@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2011-07-01

    The prostate cancer, which is the second cause of death by cancer in men, overcome only by lung cancer is public health problem in Brazil. Brachytherapy is among the possible available treatments for prostate cancer, in which small seeds containing Iodine-125 radioisotope are implanted into the prostate gland. The seed consists of a titanium sealed capsule with 0.8 mm external diameter and 4.5 mm length, containing a central silver wire with adsorbed Iodine-125. The Plasma Arc Welding (PAW) is one of the viable techniques for sealing process. The equipment used in this technique is less costly than in other processes, such as, Laser Beam Welding (LBW). The main purpose of this work was the development of an encapsulation method using PAW. The development of this work has presented the following phases: cutting and cleaning titanium tube, determination of the welding parameters, development of a titanium tube holding device for PAW, sealed sources validation according to ISO 2919 - Sealed Radioactive Sources - General Requirements and Classification, and metallographic assays. The developed procedure to seal Iodine-125 seeds using PAW has shown high efficiency, satisfying all the established requirements of ISO 2919. The results obtained in this work will give the possibility to establish a routine production process according to the orientations presented in resolution RDC 17 - Good Manufacturing Practices to Medical Products defined by the ANVISA - National Agency of Sanitary Surveillance. (author)

  8. Development of an encapsulation method using plasma arc welding to produce iodine-125 seeds for brachytherapy

    International Nuclear Information System (INIS)

    Feher, Anselmo; Calvo, Wilson A.P.; Rostelato, Maria E.C.M.; Zeituni, Carlos A.; Somessari, Samir L.; Costa, Osvaldo L.; Moura, Joao A.; Moura, Eduardo S.; Souza, Carla D.; Rela, Paulo R.

    2011-01-01

    The prostate cancer, which is the second cause of death by cancer in men, overcome only by lung cancer is public health problem in Brazil. Brachytherapy is among the possible available treatments for prostate cancer, in which small seeds containing Iodine-125 radioisotope are implanted into the prostate gland. The seed consists of a titanium sealed capsule with 0.8 mm external diameter and 4.5 mm length, containing a central silver wire with adsorbed Iodine-125. The Plasma Arc Welding (PAW) is one of the viable techniques for sealing process. The equipment used in this technique is less costly than in other processes, such as, Laser Beam Welding (LBW). The main purpose of this work was the development of an encapsulation method using PAW. The development of this work has presented the following phases: cutting and cleaning titanium tube, determination of the welding parameters, development of a titanium tube holding device for PAW, sealed sources validation according to ISO 2919 - Sealed Radioactive Sources - General Requirements and Classification, and metallographic assays. The developed procedure to seal Iodine-125 seeds using PAW has shown high efficiency, satisfying all the established requirements of ISO 2919. The results obtained in this work will give the possibility to establish a routine production process according to the orientations presented in resolution RDC 17 - Good Manufacturing Practices to Medical Products defined by the ANVISA - National Agency of Sanitary Surveillance. (author)

  9. Dosimetric study in iodine-125 seeds for brachytherapy application

    International Nuclear Information System (INIS)

    Zeituni, Carlos Alberto

    2008-01-01

    The demand for iodine-125 seeds for use in brachytherapy treatments has experienced an increase along recent years in Brazil and all over the world. All iodine-125 seed must have its operational parameters measured and/or calculated every time changes in the production process are carried out. A complete dosimetric measurement is very expensive, and it is recommended that this procedure must be repeated at least once a year. Thus, this work developed a methodology for the entire dosimetric process. This methodology is based on the scarce information available in the literature, once almost all the methodology used in large industrial laboratories is commercial secret. The proposed methodology was tested using seeds of Amersham-Oncura-Ge Healthcare, which is the largest seed manufactory in the world. In this new methodology, an automatic reader was employed in order to reduce the time required in the selection process of the TLD-100 dosimeters used and a postprocessing of the obtained spectra was carried out. A total of 142 dosimeters were used and only 29 have been selected using the new methodology. Measurements were performed using slabs of Solid Water RW1 to simulate measuring in the 'water', using three different experimental apparatus and each measurement was repeated at least three times. The TLD-100 calibration was performed using a Dermopan II - Siemens. The measured values showed a good agreement with the ones available in the literature. Finally, these measured values were compared with calculated ones obtained by a semiempirical simulation program, showing a good agreement and, therefore, demonstrating the validity of the proposed methodology regarding dosimetric calculations. (author)

  10. Study and methodology development for quality control in the production process of iodine-125 radioactive sealed sources applied to brachytherapy

    International Nuclear Information System (INIS)

    Moura, Joao Augusto

    2009-01-01

    Today cancer is the second cause of death by disease in several countries, including Brazil. Excluding skin cancer, prostate cancer is the most incident in the population. Prostate tumor can be treated by several ways, including brachytherapy, which consists in introducing sealed radioactive sources (Iodine - 125 seeds) inside the tumor. The target region of treatment receives a high radiation dose, but healthy neighbor tissues receive a significantly reduced radiation dose. The seed is made of a welding sealed titanium capsule, 0.8 mm external diameter and 4.5 mm length, enclosing a 0.5 mm diameter silver wire with Iodine-125 adsorbed. After welded, the seeds have to be submitted to a leak test to prevent any radioactive material release. The aims of this work were: (a) the study of the different leakage test methods applied to radioactive seeds and recommended by the ISO 997820, (b) the choice of the appropriate method and (c) the flowchart determination of the process to be used during the seeds production. The essays exceeded the standards with the use of ultra-sound during immersion and the corresponding benefits to leakage detection. Best results were obtained with the immersion in distilled water at 20 degree C for 24 hours and distilled water at 70 degree C for 30 minutes. These methods will be used during seed production. The process flowchart has all the phases of the leakage tests according to the sequence determined in the experiments. (author)

  11. Recurrent primary lumbar vertebra chondrosarcoma: Marginal resection and Iodine-125 seed therapy

    Directory of Open Access Journals (Sweden)

    Chunpeng Ren

    2014-01-01

    Full Text Available Chondrosarcomas are uncommon in the spinal column. En bloc excisions with wide margins are of critical importance but not always feasible in spine. We report the outcome in a case of recurrent lumbar vertebral chondrosarcoma treated with marginal resection and iodine-125 seeds placed in the resected tumor bed.

  12. Development of an automation system for iodine-125 brachytherapy seed production by (Nd:YAG) laser welding

    International Nuclear Information System (INIS)

    Somessari, Samir Luiz

    2010-01-01

    The aim of this work is to develop an automation system for iodine-125 radioactive seed production by (Nd:YAG) laser welding, which has been used successfully in Low Dose Rate (LDR) brachytherapy treatment. This small seed consists of a welded titanium capsule, with 0.8mm in diameter and 4.5mm in length, containing iodine-125 adsorbed onto a silver rod. The iodine-125 seeds are implanted into the human prostate to irradiate the tumor for cancer treatment. Nowadays, the Radiation Technology Center, at IPEN-CNEN/SP imports and distributes 36,000 iodine-125 seeds per year, for the clinics and hospitals in the country. However, the Brazilian market potential is now over 8,000 iodine-125 seeds per month. The local production of these iodine-125 radioactive sources becomes a priority for the Institute, in order to reduce the price and the problems of prostate cancer management. It will permit to spread their use to a largest number of patients in Brazil. On the other hand, the industrial automation plays an important role for iodine-125 seeds in order to increase the productivity, with high quality and assurance, avoiding human factors, implementing and operating with Good Manufacturing Practices (GMP). The technology consists of appliance electronic and electro-mechanical parts and components to control machines and processes. The automation system technology for iodine-125 seed production developed in this work was mainly assembled employing Programmable Logic Controller (PLC), stepper motors, drivers, (Nd:YAG) laser welding machine, photoelectric sensors and supervisory. (author)

  13. Development of an automation system for iodine-125 brachytherapy seed production by ND:YAG laser welding

    International Nuclear Information System (INIS)

    Somessari, Samir L.; Feher, Anselmo; Sprenger, Francisco E.; Rostellato, Maria Elisa C.M.; Costa, Fabio E.; Calvo, Wilson A.P.

    2009-01-01

    The aim of this work is to develop an automation system for iodine-125 radioactive seed production by Nd:YAG laser welding, which has been used successfully in low dose rate brachytherapy treatment. This small seed consists of a welded titanium capsule, with 0.8 mm in diameter and 4.5 mm in length, containing iodine-125 adsorbed onto a silver rod. The iodine-125 seeds are implanted into the human prostate to irradiate the tumor for cancer treatment. Nowadays, the Radiation Technology Center, at IPEN-CNEN/SP imports and distributes 36,000 iodine-125 seeds per year, for the clinics and hospitals in the country. However, the Brazilian market potential is now over 8,000 iodine-125 seeds per month. The local production of these iodine-125 radioactive sources became a priority for the Institute, in order to reduce the price and the problems of prostate cancer management. It will permit to spread their use to a larger number of patients in Brazil. On the other hand, the industrial automation plays an important role for iodine-125 seeds in order to increase the productivity, with high quality and assurance, avoiding human factors, implementing and operating with good manufacturing practices. The technology consists of appliance electronic and electro-mechanical parts and components to control machines and processes. The automation system technology for iodine-125 seed production developed in this work was mainly assembled employing a Programmable Logic Controller, a stepper motor, an Nd:YAG laser welding machine and a supervisory. (author)

  14. Development of computational models for the simulation of isodose curves on dosimetry films generated by iodine-125 brachytherapy seeds

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Adriano M.; Meira-Belo, Luiz C.; Reis, Sergio C.; Grynberg, Suely E., E-mail: amsantos@cdtn.b [Center for Development of Nuclear Technology (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2011-07-01

    The interstitial brachytherapy is one modality of radiotherapy in which radioactive sources are placed directly in the region to be treated or close to it. The seeds that are used in the treatment of prostate cancer are generally cylindrical radioactive sources, consisting of a ceramic or metal matrix, which acts as the carrier of the radionuclide and as the X-ray marker, encapsulated in a sealed titanium tube. This study aimed to develop a computational model to reproduce the film-seed geometry, in order to obtain the spatial regions of the isodose curves produced by the seed when it is put over the film surface. The seed modeled in this work was the OncoSeed 6711, a sealed source of iodine-125, which its isodose curves were obtained experimentally in previous work with the use of dosimetric films. For the films modeling, compositions and densities of the two types of dosimetric films were used: Agfa Personal Monitoring photographic film 2/10, manufactured by Agfa-Geavaert; and the model EBT radiochromic film, by International Specialty Products. The film-seed models were coupled to the Monte Carlo code MCNP5. The results obtained by simulations showed to be in good agreement with experimental results performed in a previous work. This indicates that the computational model can be used in future studies for other seeds models. (author)

  15. Experimental iodine-125 seed irradiation of intracerebral brain tumors in nude mice

    Directory of Open Access Journals (Sweden)

    Haveman Jaap

    2007-09-01

    Full Text Available Abstract Background High-dose radiotherapy is standard treatment for patients with brain cancer. However, in preclinical research external beam radiotherapy is limited to heterotopic murine models– high-dose radiotherapy to the murine head is fatal due to radiation toxicity. Therefore, we developed a stereotactic brachytherapy mouse model for high-dose focal irradiation of experimental intracerebral (orthotopic brain tumors. Methods Twenty-one nude mice received a hollow guide-screw implanted in the skull. After three weeks, 5 × 105 U251-NG2 human glioblastoma cells were injected. Five days later, a 2 mCi iodine-125 brachytherapy seed was inserted through the guide-screw in 11 randomly selected mice; 10 mice received a sham seed. Mice were euthanized when severe neurological or physical symptoms occurred. The cumulative irradiation dose 5 mm below the active iodine-125 seeds was 23.0 Gy after 13 weeks (BEDtumor = 30.6 Gy. Results In the sham group, 9/10 animals (90% showed signs of lethal tumor progression within 6 weeks. In the experimental group, 2/11 mice (18% died of tumor progression within 13 weeks. Acute side effects in terms of weight loss or neurological symptoms were not observed in the irradiated animals. Conclusion The intracerebral implantation of an iodine-125 brachytherapy seed through a stereotactic guide-screw in the skull of mice with implanted brain tumors resulted in a significantly prolonged survival, caused by high-dose irradiation of the brain tumor that is biologically comparable to high-dose fractionated radiotherapy– without fatal irradiation toxicity. This is an excellent mouse model for testing orthotopic brain tumor therapies in combination with radiation therapy.

  16. Experimental iodine-125 seed irradiation of intracerebral brain tumors in nude mice

    International Nuclear Information System (INIS)

    Verhoeff, Joost JC; Stalpers, Lukas JA; Coumou, Annet W; Koedooder, Kees; Lavini, Cristina; Van Noorden, Cornelis JF; Haveman, Jaap; Vandertop, William P; Furth, Wouter R van

    2007-01-01

    High-dose radiotherapy is standard treatment for patients with brain cancer. However, in preclinical research external beam radiotherapy is limited to heterotopic murine models– high-dose radiotherapy to the murine head is fatal due to radiation toxicity. Therefore, we developed a stereotactic brachytherapy mouse model for high-dose focal irradiation of experimental intracerebral (orthotopic) brain tumors. Twenty-one nude mice received a hollow guide-screw implanted in the skull. After three weeks, 5 × 10 5 U251-NG2 human glioblastoma cells were injected. Five days later, a 2 mCi iodine-125 brachytherapy seed was inserted through the guide-screw in 11 randomly selected mice; 10 mice received a sham seed. Mice were euthanized when severe neurological or physical symptoms occurred. The cumulative irradiation dose 5 mm below the active iodine-125 seeds was 23.0 Gy after 13 weeks (BED tumor = 30.6 Gy). In the sham group, 9/10 animals (90%) showed signs of lethal tumor progression within 6 weeks. In the experimental group, 2/11 mice (18%) died of tumor progression within 13 weeks. Acute side effects in terms of weight loss or neurological symptoms were not observed in the irradiated animals. The intracerebral implantation of an iodine-125 brachytherapy seed through a stereotactic guide-screw in the skull of mice with implanted brain tumors resulted in a significantly prolonged survival, caused by high-dose irradiation of the brain tumor that is biologically comparable to high-dose fractionated radiotherapy– without fatal irradiation toxicity. This is an excellent mouse model for testing orthotopic brain tumor therapies in combination with radiation therapy

  17. Iodine-125 thin seeds decrease prostate swelling during transperineal interstitial permanent prostate brachytherapy

    International Nuclear Information System (INIS)

    Beydoun, Nadine; Bucci, Joseph A.; Chin, Yaw S.; Malouf, David

    2014-01-01

    Prostate swelling following seed implantation is a well-recognised phenomenon. The purpose of this intervention was to assess whether using thinner seeds reduces post-implant swelling with permanent prostate brachytherapy. Eighteen consecutive patients eligible for prostate seed brachytherapy underwent seed implantation using iodine-125 (I-125) thin seeds. Operative time, dosimetry, prostate swelling and toxicity were assessed and compared with standard I-125 stranded seed controls, sourced from the department's brachytherapy database. A learning curve was noted with the thin seeds in terms of greater bending and deviation of needles from their intended path. This translated into significantly longer total operative time (88 vs 103 minutes; P=0.009, 95% confidence interval (CI) 4.1-24.3) and time per needle insertion (2.6 vs 3.7 minutes; P<0.001, 95% CI 0.5-1.3) for the thin seeds. Day 30 prostate volumes were significantly smaller in the thin seed group compared with standard seeds (40.9cc vs 46.8cc; P=0.001, 95% CI 1.5-5.6). The ratio of preoperative transrectal ultrasound to day 30 post-implant CT volume was also smaller in the thin seed group (1.2±0.1 for standard seeds vs 1.1±0.1 for thin seeds). Post-implant dosimetric parameters were comparable for both groups. No significant differences were seen in acute urinary morbidity or quality of life between the two groups. I-125 thin seeds are associated with an initial learning curve, with longer operative time, even for experienced brachytherapists. The significant reduction in day 30 prostate volumes with the thin seeds has useful implications in terms of optimising dose coverage to the prostate in the early period post-implantation, as well as improving the accuracy of post-implant dosimetric assessments.

  18. Radiation exposure to operating room staff during prostate brachytherapy using iodine-125 seeds

    International Nuclear Information System (INIS)

    Gagna, G.; Amabile, J.C.; Laroche, P.; Gauron, C.

    2011-01-01

    The French defense radiation protection service (SPRA) and the French national institute for research and safety (INRS) conducted a joint study to assess the radiation exposure to operating room staff during prostate brachytherapy using iodine-125 seeds at the Val-de-Grace military hospital. The purpose of the study was the assessment of the effective doses, the equivalent doses to the extremities and lens received by a novice team, the different ambient dose equivalent rates measurements and the delineation of areas. After six brachy-therapies, all the recorded doses with whole-body InLight R OSL and nanoDot R dosimeters remained below the detection limit for the whole staff. The dose rate measured at the end of implantation by an AT1123 R survey meter is about 170 μSv/h at the perineum of the patient. The controlled area limit is estimated to be about 20 cm from the patient perineum. From these results, the authors propose recommendations for the categorization of workers, the delineation of areas and the dose monitoring procedures. This study demonstrates that real-time ultrasound-guided trans-perineal prostate brachytherapy delivers low dose to the operators because of the radioactive source characteristics and the instrumentation providing an effective radiation protection for the surgical team. (authors)

  19. Patterns of failure after iodine-125 seed implantation for prostate cancer

    International Nuclear Information System (INIS)

    Lamb, David S.; Greig, Lynne; Russell, Grant L.; Nacey, John N.; Broome, Kim; Studd, Rod; Delahunt, Brett; Iupati, Douglas; Jain, Mohua; Rooney, Colin; Murray, Judy; Lamb, Peter J.; Bethwaite, Peter B.

    2014-01-01

    Purpose: To determine the site of relapse when biochemical failure (BF) occurs after iodine-125 seed implantation for prostate cancer. Materials and methods: From 2001–2009, 500 men underwent implantation in Wellington, New Zealand. Men who sustained BF were placed on relapse guidelines that delayed restaging and intervention until the prostate-specific antigen (PSA) was ⩾20 ng/mL. Results: Most implants (86%) had a prostate D90 of ⩾90%, and multivariate analysis showed that this parameter was not a variable that affected the risk of BF. Of 21 BFs that occurred, the site of failure was discovered to be local in one case and distant in nine cases. Restaging failed to identify the site of relapse in two cases. In nine cases the trigger for restaging had not been reached. Conclusions: If post-implant dosimetry is generally within the optimal range, distant rather than local failure appears to be the main cause of BF. Hormone treatment is therefore the most commonly indicated secondary treatment intervention (STI). Delaying the start of STI prevents the unnecessary treatment of men who undergo PSA ‘bounce’ and have PSA dynamics initially mimicking those of BF

  20. Statistical differences and systematic effect on measurement procedure in thermoluminescent dosimetry of the Iodine-125 brachytherapy seed

    Energy Technology Data Exchange (ETDEWEB)

    Zeituni, Carlos A.; Moura, Eduardo S.; Rostelato, Maria Elisa C.M.; Manzoli, Jose E.; Moura, Joao Augusto; Feher, Anselmo, E-mail: czeituni@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP) Sao Paulo, SP (Brazil); Karam, Dib [Universidade de Sao Paulo (USP Leste), Sao Paulo, SP (Brazil). Escola de Artes, Ciencias e Humanidades

    2009-07-01

    In order to provide the dosimetry for Iodine-125 seed production in Brazil, Harshaw thermoluminescent dosimeters (TLD-100) will be used. Even if measurements with TLD-100 of the same batch of fabrication are performed, the response will not be the same. As a consequence, they must be measured one by one. These dosimeters are LiF type with a micro-cube (1 mm x 1 mm x 1 mm) shape. Irradiations were performed using Iodine-125 seeds to guarantee the same absorbed dose of 5 Gy in each dosimeter. It has been used a Solid Water Phantom with three concentrically circle with 20 mm, 50 mm and 70 mm diameters. The angle of positions used was 0 deg, 30 deg, 60 deg and 90 deg. Of course there are 2 positions in 0 deg and 90 deg and 4 positions in 30 deg and 60 deg. These complete procedures were carried out five times in order to compare the data and minimize the systematic error. The iodine-125 seed used in the experiment was take off in each measure and put again turning his position 180 deg to guarantee the systematic error was minimized. This paper presents also a little discussion about the statistical difference in the measurement and the calculation procedure to determine the systematic error in these measurements. (author)

  1. Survival benefit of chemoembolization plus Iodine125 seed implantation in unresectable hepatitis B-related hepatocellular carcinoma with PVTT: a retrospective matched cohort study

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Mingsheng; Wang, Haofan; Chen, Junwei; Bai, Mingjun; Wang, Long; Zhu, Kangshun; Jiang, Zaibo; Guan, Shouhai; Li, Zhengran; Qian, Jiesheng; Li, Mingan; Pang, Pengfei; Shan, Hong [Sun Yat-sen University, Department of Radiology, the Third Affiliated Hospital, Guangzhou (China); Sun Yat-Sen University, Department of Interventional Radiology, Ling-nan Hospital, Guangzhou (China); Sun Yat-sen University, Interventional Radiology Institute, Guangzhou (China); Lin, Qu [Sun Yat-sen University, Department of Oncology, the Third Affiliated Hospital, Guangzhou (China)

    2016-10-15

    To investigate the survival benefit of transarterial chemoembolization (TACE) plus Iodine125 seed implantation (TACE-Iodine125) in hepatitis B-related HCC patients with portal vein tumour thrombus (PVTT) and the underlying prognostic factors. A retrospective matched cohort study was performed on consecutive HCC patients with PVTT from January 2011 to June 2014. Seventy patients (TACE-Iodine125 group) who underwent TACE-Iodine125 were compared with a historical case-matched control group of 140 patients (TACE group) who received TACE alone. The survival of patients and the underlying prognostic factors were analysed. The median survival times of the TACE-Iodine125 and TACE groups were 11.0 and 7.5 months, respectively (p < 0.001). The survival probability at 12, 24, and 36 months was 50 %, 14.5 %, and 14.5 % vs. 25 %, 9 %, and 5 % in the TACE-Iodine125 and TACE groups, respectively (p < 0.001). The PVTT responders had better survival than the PVTT non-responders (p < 0.001). For the PVTT non-responders, there were no differences in the survival curves between the groups (p = 0.353). Multivariate analysis showed that type III PVTT (p < 0.001) and APS (p < 0.001) were independent predictors of poor prognosis. In contrast, the treatment modality of TACE-Iodine125 (p < 0.001) and PVTT response (p = 0.001) were favourable prognostic features. TACE combined with Iodine125 seed implantation may be a good choice for selected HB-HCC patients with PVTT. (orig.)

  2. SU-E-T-12: A Comparative Dosimetric Study of Pre and Post Prostate Iodine-125 Permanent Seed Implants

    Energy Technology Data Exchange (ETDEWEB)

    Liu, X; Rahimian, J; Goy, B; Cosmatos, H; Qian, Y [Kaiser Permanente, Los Angeles, CA (United States)

    2015-06-15

    Purpose: Post-implant dosimetry has become the gold standard for prostate implant evaluation. The goal of this research is to compare the dosimetry between pre-plan and post-plan in permanent prostate seed implant brachytherapy. Methods: A retrospective study of 91 patients treated with Iodine-125 prostate seed implant between year 2012∼2014 were performed. All plans were created using a VariSeed 8.0 planning system. Pre-plan ultrasound images were acquired using 0.5 cm slice thickness. Post-plan CT images acquired about 1–4 weeks after implant, fused with the preplan ultrasound images. The prostate and urethra contours were generated using the fusion of ultrasound and CT images. Iodine-125 seed source activities varied between 0.382 to 0.414 mCi per seed. The loading patterns varied slightly between patients depending on the prostate size. Statistical analysis of pre and post plans for prostate and urethra volumes, V100%, V150% and D90, and urethra D10 were performed and reported. Results: The pre and post implant average prostate size was 36.90cc vs. 38.58cc; V100% was 98.33% vs. 96.89%; V150% was 47.09% vs. 56.95%; D90 was 116.35Gy vs. 116.12Gy, urethra volume was 1.72cc vs. 1.85cc, urethra D10% was 122.0% vs. 135.35%, respectively. There was no statistically significant difference between the pre and post-plan values for D90(p-value=0.43). However, there are significant differences between other parameters most likely due to post surgical edema; prostate size (p-value= 0.00015); V100% (p-value=3.7803E-07); V150% (p-value=1.49E-09); urethra volume (p-value= 2.77E-06); Urethra D10 (p-value=7.37E-11). Conclusion: The post-plan dosimetry using CT image set showed similar D90 dose coverage to the pre-plan using the ultrasound image dataset. The study showed that our prostate seed implants have consistently delivered adequate therapeutic dose to the prostate while sparing urethra. Future studies to correlate dose versus biochemical response using patients’ PSA

  3. Iodine-125 seed implantation for unresectable pancreatic carcinoma guided by intraoperative ultrasound

    International Nuclear Information System (INIS)

    Wang Junjie; Xiu Dianrong; Ran Weiqiang; Bai Jing; Zhu Lihong; Liu Jiangping

    2005-01-01

    Objective: To investigate the surgical technique, efficacy and side effects of 125 I seed interstitial implantation for pancreatic carcinoma. Methods: A total of 22 patients with biopsy proven unresectable adenocarcinoma of pancreas were treated with 125 I implants during laparotomy. Of them 11 patients were treated previously by a combination of bypass surgery. The stent was implanted in 2 cases 2 weeks before and 4 weeks after seed implantation. Seed needles were implanted parallelly to each other, with 1-1.5 cm apart. Mick applicator was being connected to each needle to implant seed. The radioactive activity ranged 0.40-0.70 mCi, the matched peripheral doses were 65-145 Gy. The mean number of 125 I seed was 11-78. Five cases received external beam irradiation with 3D-CRT, the doses were 39-70 Gy and 5 patients received 2 cycle of gemcitabine chemotherapy at 1000 mg/m 2 on dl and d8. Results: Pain was completely relieved in 12 cases, partially relieved in 2 cases, and no response was noted in one case, so the response rate was 93.33%. The median time was 2-3 d. Altogethe 27.27% of the cases died from local recurrence of pancreatic carcinoma and 50% from metastasis. The median survival time in these patients was 6 months, with a 2-year survival rate of 9.09%. The seed immigrated to liver in 3 cases. There were no serious side effects such as infection, pancreatitis, pancreatic fistula, etc. Conclusion: Radioactive seed implantation was safe, high local control, minidamage, satisfactory palliation of pain and without significant complications. (authors)

  4. Intraoperative ultrasound quided iodine-125 seed implantation for unresectable pancreatic carcinoma

    International Nuclear Information System (INIS)

    Wang Junjie; Liu Jiangping; Jiang Yuliang; Jiang Weijuan; Li Jinna; Xiu Dianrong; Ran Weiqiang

    2007-01-01

    Objective: To investigate the surgical technique, efficacy and side effects of intraoperative ultrasound quided 125 I seed interstitial implantation for pancreatic carcinoma. Methods: Twenty-seven patients with biopsy proven unresectable adenocarcinoma of pancreas were treated with 125 I implants during laparotomy. Eleven patients were treated by a combination of bypass surgery. Seed needles were implanted parallel to each other, at 1.0-1.5 cm apart and guided by ultrasound. Mick applicator was applied to each needle to implant seed at 1.0-1.5 cm apart. The radioactive activity ranged 0.40-0.70 mCi; the D 90 were 110-160 Gy. The mean number of 125 I seed were 11-78. Six patients also received external beam radiation at doses of 39-50 Gy. Five patients received 2-4 cycle DDP + gemCitabine chemotherapy also. Results: The incidence of perioperative mortality was 0%. Pain was complete relieved in 15 patients, partial relieved in two, but in the rest three patients there was no response. The response rate was 85%. The starting time of pain relief was 1-30 d, with a median of 5 days. The overall local control rate was 74%. Four patients have died of recurrence, 20 patients died of metastasis, 3 patients died of recurrence and metastasis. The median survival of II + III[ stage patients was 8 months, with a 1- and 2-year survival of 25% and 15%, respectively. The median survival time of IV stage patients was 5 months, with 1-year survival of 8%. The seeds immigrated into the liver in 3 patients. There are no serious side effects such as infection or pancreatic fistula. Conclusions: Intraoperative ultrasound quided 125 I seed implantation is safe, giving high local control, but minimal damage. It is a satisfactorily palliative for pain and causing little noticeable complications. (authors)

  5. Clinical efficacy of computed tomography-guided iodine-125 seed implantation therapy in patients with advanced spinal metastatic tumors

    Directory of Open Access Journals (Sweden)

    Zhang LY

    2015-12-01

    Full Text Available Liyun Zhang,1,2,* Jian Lu,2,* Zhongmin Wang,3 Yingsheng Cheng,4 Gaojun Teng,5 Kemin Chen4 1Medical College of Soochow University, Suzhou, 2Department of Radiology, Shanghai Ruijin Hospital Luwan Branch, 3Department of Radiology, Shanghai Ruijin Hospital, 4Department of Radiology, Shanghai the Sixth People Hospital, Shanghai, 5Department of Radiology, Jiangsu Key Laboratory of Molecular and Functional Imaging, Zhongda Hospital, Medical School, Southeast University, Nanjing, People’s Republic of China *These authors contributed equally to this work Objective: The purpose of this study was to examine the safety and clinical efficacy of computed tomography (CT-guided radioactive iodine-125 (125I seed implantation treatment in patients with spinal metastatic tumors.Methods: We retrospectively analyzed 20 cases of spinal metastatic tumors, including nine men and eleven women aged 50–79 years (mean age: 61.1 years. We used treatment planning system (TPS to construct three-dimensional images of the spinal metastatic tumors and to determine what number and dose rate distribution to use for the 125I seeds. The matched peripheral dose of the 125I seed implantation was 90–130 Gy. Twenty-four spinal metastatic tumors were treated by CT-guided radioactive 125I seed implantation. A median of 19 (range: 4–43 125I seeds were implanted.Results: Twenty cases were followed for a median of 15.3 months (range: 7–32 months. The rate of pain relief was 95%. The median control time for all of the patients was 12.5 months. The 3-, 6-, and 12-month cumulative local control rates were 100%, 95%, and 60%, respectively. The median survival time for all of the patients was 16 months. The cumulative 6- and 12-month survival rates were 100% and 78.81%, respectively. No major complications were observed. No 125I seeds were lost or migrated to other tissues or organs.Conclusion: CT-guided radioactive 125I seed implantation is a safe, effective, and minimally

  6. Radio-guided occult lesion localisation using iodine-125 seeds ('ROLLIS') for removal of impalpable breast lesions: first Australian experience

    International Nuclear Information System (INIS)

    Taylor, Donna B.; Bourke, Anita G.; Westcott, Eliza

    2015-01-01

    Approximately one-third of breast cancers are impalpable and require pre-operative image-guided localisation. Hook-wire localisation (HWL) is commonly used but has several disadvantages. Use of a low-activity radioactive iodine-125 seed is a promising alternative technique used in the USA and the Netherlands. This pilot study describes the first use of this in Australia. In this prospective pilot study, 21 participants with biopsy-proven breast cancer underwent radio guided occult lesion localisation using iodine-125 seed(s) (ROLLIS) with insertion of a hook-wire for back up. Sentinel node biopsy was performed where indicated. Ease of hook-wire and seed insertion, duration of the procedure, dependence on the seed versus hook-wire during surgery, lesion location within the specimen, histopathology including size of radial margins, the ease of seed retrieval in pathology, and safe return of seeds for disposal were documented. Radiation dosimetry of staff was performed. All seeds were placed within 3.5 mm of the lesion. All lesions and seeds were removed. One participant needed re-excision for involved margins. Radiologists and surgeons both preferred ROLLIS. Surgeons were able to depend on the seed for localisation in all but one case. Sentinel node biopsy was successfully performed when required. Pathologists found seed retrieval quick and easy, with no detrimental effect on tissue processing. No radiation doses measurably above background were received by staff. ROLLIS is an easily learnt, safe and effective alternative technique to standard HWL.

  7. Procedure for determination of the decontamination of piping in the production of iodine-125 seeds; Procedimento para determinacao da descontaminacao de tubulacoes, na producao de sementes de iodo-125

    Energy Technology Data Exchange (ETDEWEB)

    Moura, J.A.; Moura, E.S.; Sprenger, F.E.; Nagatomi, H.R.; Zeituni, C.A.; Feher, A.; Manzoli, J.E.; Souza, C.D.; Rostelato, M.E.C.M., E-mail: elisaros@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2009-07-01

    Iodine-125 seeds are radioactive sources used in the prostate cancer treatment. This work objective was to determine the necessary conditions and procedures for decontamination of liquid transfer tubes when a radioactive material leakage occurs during the process of seed quality control

  8. Mock iodine-125 radiation source

    International Nuclear Information System (INIS)

    Coffey, D.L.

    1976-01-01

    An intimate mixture of americium-241 and iodine-129 provides an energy spectrum that reliably simulates the spectrum of iodine-125 in a well-type detector. As such, it may be used as a long-lived standard to calibrate instruments such as well scintillation spectrometers in which measurements are to be made involving iodine-125

  9. Irradiation of malignant eyelid melanoma with iodine 125 plaque

    International Nuclear Information System (INIS)

    Stanowsky, A.; Krey, H.F.; Kopp, J.; Kanitz, W.; Wagner, T.

    1990-01-01

    We used contact irradiation with iodine 125 seeds to treat a large, exulcerative, nodular, amelanotic malignant eyelid melanoma with metastasis to the regional lymph nodes in an 80-year-old man. The procedure was similar to iodine 125 plaque irradiation of malignant choroidal melanoma; special equipment, however, was needed to protect the eye from radiation exposure. The response of the malignant eyelid melanoma to iodine 125 plaque irradiation was similar to that of malignant melanomas of the choroid. No complications were observed in a follow-up period of 15 months

  10. Irradiation of malignant eyelid melanoma with iodine 125 plaque

    Energy Technology Data Exchange (ETDEWEB)

    Stanowsky, A.; Krey, H.F.; Kopp, J.; Kanitz, W.; Wagner, T. (Eye Clinic, Central Clinic, Augsburg (West Germany))

    1990-07-15

    We used contact irradiation with iodine 125 seeds to treat a large, exulcerative, nodular, amelanotic malignant eyelid melanoma with metastasis to the regional lymph nodes in an 80-year-old man. The procedure was similar to iodine 125 plaque irradiation of malignant choroidal melanoma; special equipment, however, was needed to protect the eye from radiation exposure. The response of the malignant eyelid melanoma to iodine 125 plaque irradiation was similar to that of malignant melanomas of the choroid. No complications were observed in a follow-up period of 15 months.

  11. An analysis of brachytherapy with computed tomography-guided permanent implantation of Iodine-125 seeds for recurrent nonkeratin nasopharyngeal carcinoma

    Directory of Open Access Journals (Sweden)

    Shen X

    2015-05-01

    Full Text Available Xinying Shen,1,2 Yong Li,2 Yanfang Zhang,2 Jian Kong,2 Yanhao Li1 1Department of Interventional Radiology, Nanfang Hospital, Southern Medical University, Guangzhou, 2Department of Interventional Radiology, Shenzhen People’s Hospital, The Second Clinical Medical College of Jinan University, Shenzhen, People’s Republic of China Background: 125I seed implantation is a new method in treatment of nasopharyngeal carcinoma (NPC, and it is worthwhile to evaluate its feasibility. In this study, we performed brachytherapy with computed tomography (CT-guided permanent implantation of 125I seeds in the treatment of patients with the recurrence of NPC.Methods: A total 30 patients (20 male and ten female at the median age of 55 (range 25–80 years were diagnosed with recurrent nonkeratin NPC, with a total 38 lesions and a short disease-free interval (median ~11 months after primary radiotherapy alone or combined with chemotherapy. Patients received CT scan, starting from 2 months after the treatment. Follow-up was conducted for ~2–38 months to observe the local control rate and overall survival rate. We also analyzed the possible correlation between survival periods and the status of recurrent tumors.Results: The local control rates at 6, 12, 24, 30, and 36 months after the procedure of 125I seed implantation were 86.8%, 73.7%, 26.3%, 15.8%, and 5.3%, respectively. The overall 1-, 2-, and 3-year survival rates were 80.0% (24/30, 30.0% (9/30, and 6.7% (2/30, respectively, with a median survival period of 18 months (17.6±8.6 months. Interestingly, the survival periods of the patients who had primary radiotherapy with or without chemotherapy were 15.8±7.9 and 24.3±7.9 months, respectively. Kaplan–Meier survival analysis demonstrated that χ2 (log rank was 7.555, with very significant difference (P<0.01. The survival periods of patients in tumor stages I, II, III, and IV were 25.4±8.7, 19.8±9.4, 16.1±4.5, and 12.8±7.8 months, respectively, with

  12. Study on iodine-125 production technique

    International Nuclear Information System (INIS)

    Liu Yishu; Han Dongqiao; Lu Changlong; Sun Wenhao; Bao Jianying; Wang Aimin

    1999-11-01

    125 I is produced with natural xenon as target material. The target preparation process is presented. Required xenon is frozen in 100 ml aluminum container by liquid nitrogen and sealed by cold-welding for irradiation in reactor. I - can be adsorbed on Platinum Coated Copper (PCC) in the media of dilute sulfuric acid, pH 3 PCC. In the range of its adsorption capacity, the adsorption efficiency of iodine-125 on PCC is greater than 99.9%. All the radioiodine can be adsorbed on PCC quantifiably and the impurities pass through the column. The elution efficiency of 125 I from PCC column greatly depends on the concentration of eluant NaOH, the amount of adsorbed 125 I - and flow rate as well. The aluminum dissolved from Al container has no apparent effects on both adsorption and elution efficiency. The contents of adsorbent material Cu and Pt is extremely low ( 125 I produced by using PCC chromatographic technique can meet the requirement of RIA kits labelling and other uses

  13. Radiation exposure to operating room staff during prostate brachytherapy using iodine-125 seeds; Exposition radiologique de l'equipe operatoire au cours de curietherapies de prostate par implants permanents d'iode-125

    Energy Technology Data Exchange (ETDEWEB)

    Gagna, G.; Amabile, J.C.; Laroche, P. [Service de protection radiologique des armees (SPRA), 1 bis rue du Lieutenant Raoul Batany, 92141 Clamart Cedex (France); Gauron, C. [Institut national de recherche et de securite (INRS), Departement Etudes et Assistance Medicales, 30 rue Olivier Noyer, 75680 Paris Cedex 14 (France)

    2011-04-15

    The French defense radiation protection service (SPRA) and the French national institute for research and safety (INRS) conducted a joint study to assess the radiation exposure to operating room staff during prostate brachytherapy using iodine-125 seeds at the Val-de-Grace military hospital. The purpose of the study was the assessment of the effective doses, the equivalent doses to the extremities and lens received by a novice team, the different ambient dose equivalent rates measurements and the delineation of areas. After six brachy-therapies, all the recorded doses with whole-body InLight{sup R} OSL and nanoDot{sup R} dosimeters remained below the detection limit for the whole staff. The dose rate measured at the end of implantation by an AT1123{sup R} survey meter is about 170 {mu}Sv/h at the perineum of the patient. The controlled area limit is estimated to be about 20 cm from the patient perineum. From these results, the authors propose recommendations for the categorization of workers, the delineation of areas and the dose monitoring procedures. This study demonstrates that real-time ultrasound-guided trans-perineal prostate brachytherapy delivers low dose to the operators because of the radioactive source characteristics and the instrumentation providing an effective radiation protection for the surgical team. (authors)

  14. Comparative studies on permanent prostate brachytherapy: pre-plan and real-time transrectal ultrasound guided iodine-125 seed implants at Korle-Bu Teaching Hospital, Ghana

    International Nuclear Information System (INIS)

    Kalolo, L.T.

    2013-06-01

    This research was carried out to investigate and compare the real-time and pre-plan implant at the Radiotherapy Department of the Korle Bu Teaching Hospital, Ghana. Prowess Panther 4.5 treatment planning system and variseed 7.2 software were used for pre-plan and real-time implant respectively. The study was conducted for eighty three (83) patients treated for prostate cancer through real-time implant brachytherapy between september, 2008 to April, 2013. Thirty one patients (31) patients whose ultrasound images were available were selected for the pre-plan study. The slices of ultrasound images were re-drawn on transparent A-4 sheets and later on scanned, contoured and registered in the treatment planning system (prowess 4.5). After planning, the volume to be implanted, total number of needles, seeds and the total activity of the source were displayed. Comparison was done withe the pre-plan and real-time implant. In both cases the variation was below 5% as recommended in dosimetry. About 30% - 40% of the imported seeds were left un-used due to over-estimation of seeds ordered from the manufacturer (BARD Company-USA). Hence this work (pre-plan) aims to solve this problem. The comparison for dosimetric parameters was assessed for prostate, urethra and rectum as (V 95%, V 100%, V 150%, D90Gy, D90%), (D90Gy, D90%, D30Gy, D30% ) and (V 100%, D30Gy and D30%) respectively and the variation were within the limit of ± 5%. Comparison of dosimetric values for this work were done with other institutions, like Karolinska university hospital, Sweden, The institute of Curie/ hospital Cochin Group Paris-France and European recommendations. The values reported at Korle - Bu teaching hospital (this work) were in good agreement with the international guidelines. (au)

  15. Iodine-125 radiation of posterior uveal melanoma

    International Nuclear Information System (INIS)

    Packer, S.

    1987-01-01

    Twenty-eight cases of posterior choroidal melanoma were treated with iodine-125 in gold eye plaques. Eleven cases were located within 3.0 mm of the optic nerve (group A), nine were within 3.0 mm of the fovea (group B), and eight were within 3.0 mm of the optic nerve and fovea (group C). The mean follow-up of group A was 46.3 months; group B, 25.5 months; and group C, 42.7 months. Complications included macular edema, cataract and tumor growth. Visual acuity remained within two lines of that tested preoperatively for 4 of 11 patients in group A, 4 of 9 in group B, and 5 of 8 in group C. These results with iodine-125 suggest it as an appropriate treatment for patients with choroidal melanoma located near optic nerve and/or macula

  16. Iodine-125 radiation of posterior uveal melanoma

    Energy Technology Data Exchange (ETDEWEB)

    Packer, S.

    1987-12-01

    Twenty-eight cases of posterior choroidal melanoma were treated with iodine-125 in gold eye plaques. Eleven cases were located within 3.0 mm of the optic nerve (group A), nine were within 3.0 mm of the fovea (group B), and eight were within 3.0 mm of the optic nerve and fovea (group C). The mean follow-up of group A was 46.3 months; group B, 25.5 months; and group C, 42.7 months. Complications included macular edema, cataract and tumor growth. Visual acuity remained within two lines of that tested preoperatively for 4 of 11 patients in group A, 4 of 9 in group B, and 5 of 8 in group C. These results with iodine-125 suggest it as an appropriate treatment for patients with choroidal melanoma located near optic nerve and/or macula.

  17. Quality asurance of iodinated (125 I) human fibrinogen

    International Nuclear Information System (INIS)

    Vines, E.J.

    1980-05-01

    The radiopharmaceutical iodinated ( 125 I) human fibrinogen is currently used for the detection of deep vein thrombosis in the legs, a fairly common post-surgical complication. A comprehensive quality assurance programme for ( 125 I) - human fibrinogen has been determined for routine use at the Australian Radiation Laboratory, with adaptions necessary for hospital quality control testing

  18. Iodine 125 seed migration after prostate brachytherapy: a study of 170 patients; Migration des grains d'iode 125 apres curietherapie prostatique: etude d'une serie de 170 patients

    Energy Technology Data Exchange (ETDEWEB)

    Chauveinc, L.; Osseili, A.; Rosenwald, J.C.; Cosset, J.M. [Institut Curie, Dept. d' Oncologie-Radiotherapie, 75 - Paris (France); Flam, T. [Hopital Cochin, Service d' Urologie, 75 - Paris (France); Thiounn, N. [Hopital Necker, Service d' Urologie, 75 - Paris (France); Savignoni, A. [Institut Curie, Service de Statistiques, 75 - Paris (France)

    2004-08-01

    Purpose. To study the number of migrating seeds, the anatomical site of migration and possible predictive parameters of migration, after prostate cancer brachytherapy using a loose-seed (I125) implantation technique. Patients and methods. The charts of the 170 patients consecutively treated by the Institut Curie/Hospital Cochin/Hospital Necker Group between September 1, 2001 and August 31, 2002, were analysed. All seeds having migrated to the lungs and seen on the chest X-ray systematically performed at 2 months, have been recorded, as well as the seeds lost by the urines (after sieving) or in the sperm (condom). Results. Among 12,179 implanted seeds, 44 were found to have migrated (0.36%). Most of the migrating seeds (32/44; 73%), were found in the lungs. Overall, one or several seed migrations were observed in 35 patients (21% of the total number of patients in this series). In the majority of cases (77seed migrated. A significant relationship (P = 0.04) vs as found between the number of migrating seeds and the number of implanted ones (or with the prostate volume, but those two parameters were closely linked in our series). More specifically, a significant relationship (P = 0.02) could be demonstrated between the number of seeds implanted at the periphery of the prostate and the number of seeds migrating to the lungs. Conclusion. The percentage of migrating seeds observed in this series is low. actually one of the lowest found in the literature when using the loose-seed technique. There was no clinical consequences and the loss of-usually only one seed is very unlikely to alter the quality of the dose distribution. However, the predominance of pulmonary migrations in our series led us to slightly modify our implantation technique. We now try to avoid too 'peripheral' seed implantations, due to the risk of migration towards the peri-prostatic veins, and subsequently to the lungs. (author)

  19. Epoxy resins used to seal brachytherapy seed

    International Nuclear Information System (INIS)

    Ferreira, Natalia Carolina Camargos; Ferraz, Wilmar Barbosa; Reis, Sergio Carneiro dos; Santos, Ana Maria Matildes dos

    2013-01-01

    Prostate cancer treatment with brachytherapy is recommended for patients with cancer at an early stage. In this treatment, small radioactive seeds are implanted directly in the prostate gland. These seeds are composed at least of one radionuclide carrier and an X-ray marker enclosed within a metallic tube usually sealed by laser process. This process is expensive and, furthermore, it can provoke a partial volatilization of the radionuclide and change the isotropy in dose distribution around the seed. In this paper, we present a new sealing process using epoxy resin. Three kinds of resins were utilized and characterized by scanning electron microscopy (SEM), energy dispersive X ray (EDS) and by differential scanning calorimetry (DSC) after immersion in simulated body fluid (SBF) and in sodium iodine solution (NaI). The sealing process showed excellent potential to replace the sealing laser usually employed. (author)

  20. A new inexpensive customized plaque for choroidal melanoma iodine-125 plaque therapy

    International Nuclear Information System (INIS)

    Vine, A.K.; Tenhaken, R.K.; Diaz, R.F.; Maxson, B.B.; Lichter, A.S.

    1989-01-01

    The authors have developed a new inexpensive precious metal alloy plaque for use in customized iodine-125 plaque therapy. Each plaque is formed from two flat circular gold/palladium foils which are used in dental crown work. Using a simple manual mechanism, the two forms are stamped over a customized acrylic die shaped to the dimensions of the tumor base plus a 2-mm margin. Completed plaques consist of a back wall, a 2-mm side wall, and a 1.5-mm wide lip with holes for suture placement. Advantages include: simple construction from inexpensive components, customized shape, and iodine seeds that are readily visible on plane radiographs

  1. Study of CT-guided iodine-125 implantation in the treatment of rabbit VX2 tumor

    International Nuclear Information System (INIS)

    He Kewu; Gao Bin; Li Jiajia

    2008-01-01

    Objective: To evaluate the effect of CT-guided iodine-125 seed( 125 I) implantation to rabbit model VX2 tumor cell apoptosis. Methods: VX2 tumor cells were implanted into muscle of 40 rabbits legs, 3 weeks later, as the diameter of tumor reached 2 cm available for test. Randomly selected the sampling tumor on one leg of rabbit as for the test team and tumor on the contralateral leg as for control team. Under CT guidance, 125 I seeds were implanted into 20 tumor lesions of the test team, and hollow seeds were implanted into 20 tumor lesions of the control team. Instantly, 72 h, 1, 2, 3 w after operation, percutaneous tumor tissue sampling was done 0.5-1.0 cm and 1.0-1.5 cm away from seed implanted site under CT guidance; and apoptosis was investigated by FCM. Results: Instantly, 72 h, 1, 2, 3 w after treatment with iodine-125 ( 125 I) implantation, the tissue sampling away from seed 0.5-1.0 cm showed the apoptosis rates of control team and test team were respectively as follows: (5.43±0.67)% and (5.48±0.66)%, (P>0.05), (5.45±0.58)% and (11.60±0.87)%, (P O.05)of the control team and test team. Conclusions: 125 I seeds implantation can induce tumor cell apoptosis, beginning at 72 h and reached peak at 2 w and kept the high level here afterword. The apoptosis rate descended rapidly along with the increase of distance away from the 125 I seedling. (authors)

  2. DOSIMETRIC STUDY IN IODINE-125 SEEDS FOR BRACHYTHERAPY APPLICATION

    OpenAIRE

    Carlos Alberto Zeituni

    2008-01-01

    A demanda por sementes de iodo-125 para uso em braquiterapia tem crescido muito ao longo dos últimos anos, tanto no Brasil quanto no mundo. Toda semente de iodo-125 deve ter seus parâmetros operacionais medidos e/ou calculados todas as vezes que for efetuada alguma modificação na produção. Um levantamento dosimétrico completo custa bastante caro, e recomenda-se que seja refeito pelo menos uma vez por ano. Neste contexto, o presente trabalho desenvolveu uma metodologia para todo o processo dos...

  3. Iodine-125 irradiation of choroidal melanoma: clinical experience from the Prince of Wales and Sydney Eye Hospitals

    International Nuclear Information System (INIS)

    Mameghan, H.; Karolis, Ch.; Fisher, R.; Mameghan, J.; Billson, F.A.; Donaldson, E.J.; Giblin, M.E.; Hunyor, A.B.L.

    1992-01-01

    The records of 53 patients treated for choroidal melanoma between 1985 and 1989 were examined. The aim of this study was to assess the safety and short-term results of iodine-125 episcleral plaque therapy. There were 28 males and 25 females aged 20 to 77 years, treated for single tumours with a median diameter of 9 mm (range 5 to 16 mm) and with a median thickness of 4 mm (range 2 to 10 mm). The plaques containing iodine-125 seeds were chosen according to tumour size: 10 mm (16 patients); 15 mm (36 patients); 20 mm (one patient). All patients were alive at last follow-up (median 1.3 years, range 4 months to 3.3 years). Four patients underwent enucleation for melanoma progression. Thirty patients have developed some type of complication (more than one complication occurred in the same eye in 12 patients); retinitis (19), optic neuropathy (7); cataract (4), rubeosis iridis (2). Overall, visual acuity deteriorated in 32 patients, remained stable in 12 patients and improved in 9 patients. It was therefore concluded that iodine-125 plaque therapy appears to offer patients good prospects of tumour control and preservation of useful vision. 16 refs., 4 tabs

  4. Study and parameters survey for iodine-125 source dosimetry to be applied in brachytherapy; Estudo e levantamentos de parametros para dosimetria de fontes de iodo-125 aplicadas em braquiterapia

    Energy Technology Data Exchange (ETDEWEB)

    Moura, Eduardo Santana de

    2011-07-01

    The use of brachytherapy technique with iodine-125 seeds to prostate cancer treatment has been used for decades with good clinical outcomes. To aim the Brazilian population necessities, IPEN-CNEN/SP developed the iodine-125 seed prototype with national technology. The objectives of this work are the development and the study of dosimetric procedures associates with the experimental acquisition of the useful parameters for the iodine-125 dosimetric characterization and to evaluate if the developed procedures, in this work, have the basic conditions to determinate the dosimetric analysis, that are fundamental for clinical procedures. The dosimeters selected for the analysis are the TLD-100 (LiF:Mg,Ti), initially these dosimeters were submitted for two selection steps to choose the dosimeters more reproducible for the dosimetric analysis. The two steps were the selection by the mass of the dosimeters and the reproducibility after four irradiation series in a Cobalt-60 irradiator (CTR-IPEN). Afterwards these steps, the dosimeters were irradiated in linear accelerator with 6 MV energy (Service of Radiotherapy - Hospital Israelita Albert Einstein) to yield the individual calibration factors to each dosimeter. After, the dosimeters were used to the irradiations with iodine-125 seed, 6711 model, (GE-Healthcare). The irradiations and others analysis with iodine-125 seeds yield the useful values for the determination of the parameters suggested by the AAPM (American Association of Physicists in Medicine): constant of dose rate, geometry function, dose radial function and anisotropy function. The results showed good agreement with the values published by the literature, for the same iodine- 125 model, this fact confirms that the realized parameters will be able to be used for the IPEN-CNEN iodine-125 seeds dosimetry and quality control. (author)

  5. The development of a human eye model for ophthalmic iodine-125 brachytherapy dosimetry

    International Nuclear Information System (INIS)

    Mourao, A.P.; Campos, T.P.R.

    2008-01-01

    Full text: Radiotherapy is used to treat malign tumors. Radiotherapy is an alternative to enucleation in ocular tumors. However, the irradiation of ocular region can bring damages due high doses, mainly in the crystalline lens and in the bone tissue in growth phase. Brachytherapy instead of teletherapy looks for reducing doses in the crystalline lens and the adjacent tissues of the ocular globe (orbital region), minimizing side effects. Herein, some encapsulated radioisotopes in radioactive seeds applied to the ocular brachytherapy are available. Thus, a three-dimensional computational voxel model of the ocular region with its heterogeneous tissues, globe and adjacent tissues is developed. This computational model is used to simulate orbital irradiation with radioactive seeds positioned on the sclera surface through the MCNP5 code. The computational simulation allows evaluating how doses are spatially distributed in the orbital volume in treatments with the radioactive seeds of iodine-125. Therefore, the results allow comparing the spatial doses distribution obtained through the MCNP5 simulation for those two distinct types of radioactive seeds. Bench markets from literature validates the proposed simulations. (author)

  6. Computed tomographic-guided iodine-125 interstitial implants for malignant thoracic tumors

    International Nuclear Information System (INIS)

    Huang, Qiming; Chen, Jin; Chen, Qunlin; Lai, Qingquan; Cai, Siqing; Luo, Kaidong; Lin, Zhengyu

    2013-01-01

    Purpose: To evaluate the feasibility and efficacy of percutaneous interstitial brachytherapy using iodine-125 ( 125 I) radioactive seeds under computed tomographic (CT) guidance for malignant thoracic tumors. Materials and methods: Forty-one patients (34 males, 7 females; 18–90 years; mean, 63.7 years) with 77 lesions (3 in the mediastinum, 7 in the chest wall, 67 in the lung) underwent percutaneous interstitial implantation of 125 I radioactive seeds under CT guidance. A treatment planning system (TPS) was employed to calculate the number and distribution of seeds preoperatively. An 18-G needle was inserted into the lesions under CT guidance and send the seeds according to TPS. Two patients with mediastinal lesions undergoing seed implantation received an artificial pneumothorax. One patient with lung carcinoma adjacent to the anterior mediastinum underwent seed implantation through the sternum. Follow-up CT was done every 2 months postoperatively. Results: The procedure was successful in all patients. No major procedure-associated death occurred. The mean duration of follow-up was 19.4 ± 1.3 months (3–49 months). A complete response (CR) was seen in 49 lesions (63.6%), partial response (PR) in 9 lesions (11.7%), stable disease (SD) in 12 lesions (12.8%), and progressive disease (PD) in 7 lesions (7.4%). The overall response rate (CR + PR) was 75.3%; the local control rate (CR + PR + SD) was 90.9%. The 1-, 2- and 3-year progression-free rates for local tumors were 91%, 88% and 88%, respectively. The 1-, 2- and 3-year survival rates were 87%, 74% and 68%, respectively. Conclusion: Implantation of CT-guided 125 I seeds is feasible and effective for patients with malignant thoracic tumors

  7. Assessment of the risks associated with Iodine-125 handling production sources for brachytherapy

    International Nuclear Information System (INIS)

    Souza, Daiane C.B.; Rostelato, Maria Elisa C.; Vicente, Roberto; Zeituni, Carlos A.; Tiezzi, Rodrigo; Costa, Osvaldo L.; Souza, Carla D.; Peleias Junior, Fernando S.; Rodrigues, Bruna T.; Souza, Anderson S.; Batista, Talita Q.; Melo, Emerson R.; Camargo, Anderson R.; Karam Junior, Dib

    2015-01-01

    In Brazil, prostate cancer is the second most frequent disease, with an estimated 68,800 new cases in 2013. This type of cancer can be treated with brachytherapy, which uses sealed sources of Iodine-125 implanted permanently in the prostate. These sources are currently imported at a high cost, making public treatment in large scale impractical. To reduce costs and to meet domestic demand, the laboratory for production of brachytherapy sources at the Nuclear and Energy Research Institute (IPEN) is currently nationalizing the production of this radioisotope. Iodine is quite volatile making the handling of its radioactive isotopes potentially dangerous. The aim of this paper is to evaluate the risks to which workers are exposed during the production and handling of the sources. The research method consisted initially of a literature review on the toxicity of iodine, intake limits, related physical risks, handling of accidents, generation of radioactive wastes, etc. The results allowed for establishing safety and radioprotection policies in order to ensure efficient and safe production in all stages and the implementation of good laboratory practices. (author)

  8. Computed tomography-guided iodine-125 interstitial implantation as an alternative treatment option for lung cancer.

    Science.gov (United States)

    Jiang, G; Li, Z; Ding, A; Zhou, F; Jiao, W; Tang, D; Qiu, W; Yue, L; Xu, W

    2015-02-01

    The aim was to evaluate the safety, feasibility and efficacy of computed tomography (CT)-guided percutaneous interstitial brachytherapy using radioactive iodine-125 ( 125 I) seeds for the treatment of lung cancer. Included in this study were 45 male and 35 female patients aged 52-85 years (mean 72-year) who were diagnosed with lung cancer. Of the 80 cases of lung cancer, 38 were pathologically confirmed as squamous cell carcinoma, 29 as adenocarcinoma, 2 as small cell lung cancer, and 11 as metastatic lung cancer. Percutaneous interstitial implantation of radioactive 125 I seeds was performed under CT guidance. The treatment planning system was used to reconstruct three-dimensional images of the tumor to determine the quantity and distribution of 125 I seeds to be implanted. Under CT guidance, 125 I seeds were embedded into the tumor, with the matched peripheral dose set at 100-130 Gy. Follow-up CT scan was done in 2-month to explore the treatment efficacy. The procedure was successful in all patients. No major procedure-associated death occurred. The duration of follow-up was 6-month. Complete response (CR) was seen in 38 cases (47.5%), partial response (PR) in 27 cases (33.75%), stable disease (SD) in 10 cases (12.5%), and progressive disease in 5 cases (6.25%), with a local control rate (CR + PR + SD) of 93.75%. The 2-, 4- and 6-month overall response rate (CR + PR) was 78%, 83% and 81%, respectively. Implantation of CT-guided 125 I seeds is a safe and effective alternative option for the treatment of lung cancer.

  9. Local radiolytic effectiveness of Auger electrons of iodine-125 in benzene-iodine solutions

    International Nuclear Information System (INIS)

    Uenak, P.; Uenak, T.

    1987-01-01

    High radiotoxicity of iodine-125 has been mainly attributed to the local radiolytic effects of Auger electrons on biological systems. In the present study, experimental and theoretical results are compared. The agreement between the experimental and theoretical results explains that the energy absorption of iodine aggregates has an important role in the radiolytic effectiveness of Auger electrons and iodine-125 in benzene-iodine solutions. (author) 18 refs.; 3 figs

  10. Post-operative treatment of malignant salivary gland tumours of the palate with iodine-125 brachytherapy

    International Nuclear Information System (INIS)

    Stannard, Clare E.; Hering, Egbert; Hough, Jan; Knowles, Ruth; Munro, Roger; Hille, Jos

    2004-01-01

    Background and purpose: Malignant minor salivary gland tumours are usually small and clinically indistinguishable from benign lesions. Surgery is the treatment of choice with post-operative radiotherapy for involved margins or unfavourable histology. We assessed the results of a series of such patients treated with iodine-125 brachytherapy in the form of a temporary applicator or implant. Patients and methods: There were nine patients with T1/T2 tumours of the hard and/or soft palate that had been excised. All had close or involved margins. Six were treated with a dental applicator alone, two with an applicator and additional I-125 seeds in tubes and one with an implant alone. The applicator consists of two layers of plastic made from a dental impression enclosing a predetermined number of I-125 seeds, 9-39, glued to one surface and a layer of ash metal to protect the tongue. It was inserted 1-3 months post-operatively and delivered 35-62 Gy, median 56 Gy, at 5-7 mm depth over 58-156 h, median 120 h, at 0.26-0.67 Gy/h, median 0.45 Gy/h. Results: The patients have been followed up for 32-158 months, median 50 months, and there were no recurrences. The applicator was well tolerated. A confluent mucositis developed which lasted 3-4 weeks. One patient developed a mucosal ulcer which healed spontaneously. Conclusions: Brachytherapy is an effective way of delivering post-operative radiotherapy to the hard and soft palate in patients with malignant salivary gland tumours that have been incompletely excised or have unfavourable histology. Local control is excellent, treatment time is short and morbidity is minimal

  11. Iris melanoma management with iodine-125 plaque radiotherapy in 144 patients: impact of melanoma-related glaucoma on outcomes.

    Science.gov (United States)

    Shields, Carol L; Shah, Sanket U; Bianciotto, Carlos G; Emrich, Jacqueline; Komarnicky, Lydia; Shields, Jerry A

    2013-01-01

    To evaluate the outcomes of iris melanoma managed with plaque radiotherapy on the basis of the initial presence or absence of glaucoma. Retrospective, comparative case series. A total of 144 patients. Custom-designed iodine-125 plaque radiotherapy delivering planned 8000 cGy to melanoma apex using transcorneal application. Tumor control and treatment-related complications. Of 144 patients with iris melanoma, glaucoma was present at the initial visit in 58 (40%). Causes of elevated intraocular pressure included angle infiltration by melanoma in 50 patients (86%), angle neovascularization in 4 patients (7%), and hyphema in 4 patients (7%). At presentation, the eyes displaying iris melanoma with glaucoma (vs. without glaucoma) were statistically more likely to display angle tumor (66% vs. 43%), with minimal thickness (1.9 vs. 2.9 mm), and melanoma seeding in iris stroma (7 vs. 3 clock hours) and angle (5 vs. 2 clock hours). Plaque radiotherapy was performed in all cases. Kaplan-Meier estimates at 7 years post-treatment revealed no statistical differences in outcomes of local recurrence (14% vs. 15%), enucleation (14% vs. 11%), or metastasis (2% vs. 0%) comparing eyes with and without glaucoma. Of the entire group, multivariate analysis for factors predictive of recurrence included partial (vs. complete) anterior segment irradiation and postradiotherapy glaucoma. Factors related to enucleation included diabetes mellitus, poor initial visual acuity, higher radiation dose to tumor apex, and tumor recurrence. There were no factors predictive of metastasis. Iodine-125 plaque radiotherapy provides adequate tumor control for iris melanoma with a low metastatic potential of 1% at 7 years. Iris melanoma with secondary glaucoma showed a statistically significant greater likelihood of flat tumor with iris and angle seeding and no difference in outcomes compared with eyes without glaucoma. The author(s) have no proprietary or commercial interest in any materials discussed in this

  12. Iodine-125 brachytherapy as upfront and salvage treatment for brain metastases. A comparative analysis

    Energy Technology Data Exchange (ETDEWEB)

    Romagna, Alexander; Schwartz, Christoph; Tonn, Joerg-Christian; Kreth, Friedrich-Wilhelm [Ludwig-Maximilians-University, Department of Neurosurgery, Munich (Germany); Egensperger, Rupert [Ludwig-Maximilians-University, Center for Neuropathology and Prion Research, Munich (Germany); Watson, Juliana; Belka, Claus; Nachbichler, Silke Birgit [Ludwig-Maximilians-University, Department of Radiation-Oncology, Munich (Germany)

    2016-11-15

    Outcome and toxicity profiles of salvage stereotactic ablative radiation strategies for recurrent pre-irradiated brain metastases are poorly defined. This study compared risk-benefit profiles of upfront and salvage iodine-125 brachytherapy (SBT) for small brain metastases. As the applied SBT treatment algorithm required histologic proof of metastatic brain disease in all patients, we additionally aimed to elucidate the value of biopsy before SBT. Patients with small untreated (n = 20) or pre-irradiated (n =28) suspected metastases intended for upfront or salvage SBT, respectively, were consecutively included. Temporary iodine-125 implants were used (median reference dose: 50 Gy, median dose rate: 15 cGy/h). Cumulative biologically effective doses (BED) were calculated and used for risk assessment. Treatment toxicity was classified according to Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer (RTOG/EORTC) criteria. Upfront SBT was initiated in 20 patients and salvage SBT in 23. In 5 patients, salvage SBT was withheld because of proven radiation-induced lesions. Treatment groups exhibited similar epidemiologic data except for tumor size (which was slightly smaller in the salvage group). One-year local/distant tumor control rates after upfront and salvage SBT were similar (94 %/65 % vs. 87 %/57 %, p = 0.45, respectively). Grade I/II toxicity was suffered by 2 patients after salvage SBT (cumulative BED: 192.1 Gy{sub 3} and 249.6 Gy{sub 3}). No toxicity-related risk factors were identified. SBT combines diagnostic yield with effective treatment in selected patients. The low toxicity rate in the salvage group points to protective radiobiologic characteristics of continuous low-dose rate irradiation. Upfront and salvage SBT are similarly effective and safe. Histologic reevaluation should be reconsidered after previous radiotherapy to avoid under- or overtreatment. (orig.) [German] Daten zu Risiko und Effizienz ablativer

  13. Iodine-125 orbital brachytherapy with a prosthetic implant in situ

    Energy Technology Data Exchange (ETDEWEB)

    Stannard, Clare [Groote Schuur Hospital and Cape Town Univ. (South Africa). Dept. of Radiation Oncology; Maree, Gert; Munro, Roger [Groote Schuur Hospital and Cape Town Univ. (South Africa). Dept. of Medical Physics; Lecuona, Karin [Groote Schuur Hospital and Cape Town Univ. (South Africa). Dept. of Ophthalmology; Sauerwein, Wolfgang [Universitaetsklinikum Essen (Germany). Strahlenklinik, NCTeam

    2011-05-15

    Purpose: Brachytherapy is one method of irradiating the orbit after enucleation of an eye with a malignant tumor that has a potential to recur. It consists of 6 trains of I-125 seeds placed around the periphery of the orbit, a shorter central train, and a metal disc, loaded with seeds, placed beneath the eyelids. The presence of a prosthetic orbital implant requires omission of the central train and adjustment of the activity of the seeds in the anterior orbit around the prosthesis. Patients and Methods: This is a retrospective review of the technical modifications and outcome of 12 patients treated in this manner: 6 with retinoblastoma, 5 with malignant melanoma, and 1 with an intraocular rhabdomyosarcoma. The median dose was 35.5 Gy in 73 hours for retinoblastoma and 56 Gy in 141 hours for malignant melanoma. Patients with retinoblastoma and rhabdomyosarcoma also received chemotherapy. Results: The tubes can be placed satisfactorily around the prosthesis. The increased activity in the anterior half of the tubes produced comparable dose distributions. There have been no orbital recurrences, no extrusion of the prosthesis, and cosmesis is good. Conclusion: Insertion of a prosthetic implant at the time of enucleation greatly enhances the subsequent cosmetic appearance. This should be encouraged unless there is frank tumor in the orbit. Orbital brachytherapy without the central train continues to give excellent local control. The short treatment time and good cosmesis are added advantages. The patient is spared the expense and inconvenience of removing and replacing the prosthetic implant. (orig.)

  14. Multistation iodine-125 continuous air monitor with minicomputer alarm and data reduction

    International Nuclear Information System (INIS)

    Garfield, D.K.

    1978-01-01

    The components, operation, and calibration are described of a Multistation Continuous Air Monitor for the analysis of Iodine-125 and the functions of the Minicomputer in providing alarm functions and data reduction to units specified by regulation for permanent records. The sensitivity and accuracy, as well as the justification for purchase and comparison of costs with other types of air monitoring systems are also described

  15. Experimental radiotherapy of the R1H rhabdomyosarcoma of the rat: combined use of interstitial iodine-125-brachytherapy and fractionated X-irradiation

    International Nuclear Information System (INIS)

    Doll, D.

    1995-01-01

    The study described here investigated into the therapeutic effects that split-dose x-radiation combined with interstitial iodine-125 brachytherapy would have on two different lines of the R1H rhabdomyosarcoma of the rat. The following parameters were examined: local tumour control rate; growth delay; net growth delay; position, movement and loss of seeds; tumour shape. The following results were obtained: The local tumour control rate for tumours externally treated with two seeds was by 42 Gy higher than that determined for the group treated with external irradiation alone. A procedure was developed to calculate the most appropriate distance for the seeds on the basis of tumour axes and volumes. The relationship between growth delay and mean maximum distance of the seed from the tumour margin could be ascertained on a quantitative basis. The influence of the tumour shape on the result of treatment was confirmed. Although the seeds were still active at the time of recidivation and treatment was not yet terminated, it was possible to show that the tumour bed effect, which tends to distort the growth delay calculations and may even occur in externally treated seed animals, could largely be avoided in the evaluation of this study. (orig./MG) [de

  16. Prostate-specific antigen bounce following permanent iodine-125 prostate brachytherapy

    International Nuclear Information System (INIS)

    Azuma, Koji; Kikugawa, Tadahiko; Fukumoto, Tetsuya

    2013-01-01

    The purpose of this study was to evaluate a temporary increase in the prostate-specific antigen (PSA) level, so-called PSA bounce, which occurs following permanent iodine-125 prostate brachytherapy. From June 2006 to July 2011, 64 patients with localized prostate cancer were treated with brachytherapy by using iodine-125 implants. Seventeen patients received neoadjuvant hormonal therapy to reduce the prostate volume. After the treatment, patients were followed up with a PSA measurement every 3 months for the first 2 years and every 6 months thereafter. The median follow-up duration was 34.5 months (range, 3.5 to 64.0 months). PSA bounce was noted in 20 (31%) out of the 64 patients. The median time to PSA bounce was 13.3 months (range, 5.8 to 44.7 months), and 18 (90%) out of the 20 patients experienced an initial PSA increase within 24 months. The median bounce magnitude was 0.25 ng/mL (range, 0.10 to 1.36 ng/mL). PSA failure was observed in 2 (3%) out of the 64 patients, and PSA bounce was not a predictor of PSA recurrence. PSA bounce was significantly associated with post-treatment V100 and D90, but not with clinical stage, pretreatment PSA, Gleason score, neoadjuvant hormonal therapy status, or PSA failure. PSA bounce following brachytherapy is considerably common. No significant difference was found in biochemical failure-free survival between patients with and those without PSA bounce. Physicians must take PSA bounce following radiotherapy into consideration in order to avoid unnecessary salvage hormonal treatment. (author)

  17. Urethral and bladder dosimetry of total and focal salvage Iodine-125 prostate brachytherapy : Late toxicity and dose constraints

    NARCIS (Netherlands)

    Peters, Max; Van Der Voort Van Zyp, Jochem; Hoekstra, Carel; Westendorp, Hendrik; Van De Pol, Sandrine; Moerland, Marinus; Maenhout, Metha; Kattevilder, Rob; Van Vulpen, Marco

    2015-01-01

    Introduction Salvage Iodine-125 brachytherapy (I-125-BT) constitutes a curative treatment approach for patients with organ-confined recurrent prostate cancer after primary radiotherapy. Currently, focal salvage (FS) instead of whole-gland or total salvage (TS) is being investigated, to reduce severe

  18. Use of brachytherapy with permanent implants of iodine-125 in localized prostate cancer

    International Nuclear Information System (INIS)

    Bladou, F.; Serment, G.; Salem, N.; Simonian, M.; Rosello, R.; Ternier, F.

    2002-01-01

    Approximately 15,000 cases of early stage prostate cancer T1 and T2 are diagnosed every year in France by testing for PSA and performing prostatic biopsies. The treatment of these localized forms is based in most cases on radical prostatectomy or nn external beam radiotherapy. Although the ontological results obtained by these two therapeutic methods are satisfactory and equivalent in the long term, the side effects can be important. For a number of years, trans-perineal brachytherapy using permanent implants of iodine -125 or palladium-103 has proved itself as an alternative therapy with equivalent medium to long-term results. The low urinary, digestive and sexual side effects of prostate brachytherapy are important reasons for the enthusiasm among patients and the medical community for this therapy and the growing number of applications and centres which practice it. In September 1998 we started the prostate brachytherapy programmes- in Marseilles with close collaboration between the department of urology of the Hopital Salvator, and the departments of radiotherapy, medical imaging and medical physics of the Institut Paoli-Calmettes. To date, around 250 patients with localized adenocarcinoma of the prostate have benefited from this alternative therapy in our centre. Preliminary results, with a 3 year-follow-up, are comparable to results published in the literature by pioneer teams. (authors)

  19. Iodine-125 Chitosan-Vitamin C complex. Preparation, characterization and application

    Energy Technology Data Exchange (ETDEWEB)

    Elbarbary, Ahmed M. [National Center for Radiation Research and Technology, Cairo (Egypt). Polymer Chemistry Dept.; Shafik, H.M.; Ebeid, N.H.; Ayoub, S.M. [Atomic Energy Authority, Cairo (Egypt). Hot Lab. Center; Othman, Sameh H. [Atomic Energy Authority, Cairo (Egypt). Nuclear Research Center

    2015-07-01

    In heterogeneous conditions, water soluble Chitosan-Vitamin C Complex (CSVC) is successfully synthesized via the ionic interaction between γ-degraded CS and VC. Chitosan (CS) of low molecular weight (MW) is prepared using γ-irradiation method. The coupling of CS and vitamin C (VC) is carried out by the chemical treatment of VC with the γ-degraded CS. The formation of CSVC complex instead of physical mixture is confirmed by FT-IR and UV spectrometry. Characterization by transmission electron microscope (TEM) and dynamic light scattering (DLS) shows the formation of a nanostructure in 40 nm range. The preparation of labeled CSVC was performed using chloramines-T oxidation method. The labeling feasibility of CSVC nanostructure by Iodine-125 ({sup 125}I) is investigated. The optimized conditions of labeling are thought to be 50 μg of oxidizing agent, pH 3, and one minute reaction time. The Biodistribution activity of {sup 125}I radiolabeled CSVC nanostructure ({sup 125}I-CSVC) is examined on a group of different ascites tumor bearing mice. Calculation of the biodistribution percentages shows that the tumor, liver, and kidney are the targeting organs of {sup 125}I-CSVC nanostructure.

  20. Towards in vivo nuclear microscopy: iodine-125 imaging in mice using micro-pinholes

    International Nuclear Information System (INIS)

    Beekman, Freek J.; McElroy, David P.; Hoffman, Edward J.; Berger, Frank; Gambhir, Sanjiv S.; Cherry, Simon R.

    2002-01-01

    Position-sensitive gamma-radiation detectors equipped with collimators have been used for in vivo imaging of the distribution of radiolabelled molecules in laboratory animals and humans for several decades. To date, the best image resolution achieved in a rodent is on the order of 1 mm. Here we demonstrate how a basic and compact gamma camera can be constructed for in vivo radionuclide imaging in small animals, at much higher spatial resolution. Resolution improvements were obtained by combining dense, shaped, micro-pinhole apertures with iodine-125, an isotope with low energy emissions, ease of incorporation into a wide range of molecules, and straightforward translation into the clinic via other isotopes of iodine that are suitable for nuclear medicine imaging. 125 I images of test distributions and a mouse thyroid have been obtained at a resolution of as high as 200 μm using this simple bench-top camera. Possible future applications and extension to ultra-high-resolution emission tomography are discussed. (orig.)

  1. Outcomes of Iodine-125 Plaque Brachytherapy for Uveal Melanoma With Intraoperative Ultrasonography and Supplemental Transpupillary Thermotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Badiyan, Shahed N. [Department of Radiation Oncology, Mallinckrodt Institute of Radiology, St. Louis, Missouri (United States); Rao, Rajesh C. [Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, St. Louis, Missouri (United States); Apicelli, Anthony J.; Acharya, Sahaja; Verma, Vivek; Garsa, Adam A.; DeWees, Todd; Speirs, Christina K.; Garcia-Ramirez, Jose; Esthappan, Jacqueline; Grigsby, Perry W. [Department of Radiation Oncology, Mallinckrodt Institute of Radiology, St. Louis, Missouri (United States); Harbour, J. William, E-mail: JWHarbour@med.miami.edu [Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, St. Louis, Missouri (United States); Ocular Oncology Service, Department of Ophthalmology, Bascom Palmer Eye Institute and Sylvester Comprehensive Cancer Center, University of Miami Miller School of Medicine, Miami, Florida (United States)

    2014-03-15

    Purpose: To assess the impact on local tumor control of intraoperative ultrasonographic plaque visualization and selective application of transpupillary thermotherapy (TTT) in the treatment of posterior uveal melanoma with iodine-125 (I-125) episcleral plaque brachytherapy (EPB). Methods and Materials: Retrospective analysis of 526 patients treated with I-125 EPB for posterior uveal melanoma. Clinical features, dosimetric parameters, TTT treatments, and local tumor control outcomes were recorded. Statistical analysis was performed using Cox proportional hazards and Kaplan-Meier life table method. Results: The study included 270 men (51%) and 256 women (49%), with a median age of 63 years (mean, 62 years; range, 16-91 years). Median dose to the tumor apex was 94.4 Gy (mean, 97.8; range, 43.9-183.9) and to the tumor base was 257.9 Gy (mean, 275.6; range, 124.2-729.8). Plaque tilt >1 mm away from the sclera at plaque removal was detected in 142 cases (27%). Supplemental TTT was performed in 72 patients (13.7%). One or 2 TTT sessions were required in 71 TTT cases (98.6%). After a median follow-up of 45.9 months (mean, 53.4 months; range, 6-175 months), local tumor recurrence was detected in 19 patients (3.6%). Local tumor recurrence was associated with lower dose to the tumor base (P=.02). Conclusions: Ultrasound-guided plaque localization of I-125 EPB is associated with excellent local tumor control. Detection of plaque tilt by ultrasonography at plaque removal allows supplemental TTT to be used in patients at potentially higher risk for local recurrence while sparing the majority of patients who are at low risk. Most patients require only 1 or 2 TTT sessions.

  2. Immunospecific red cell binding of iodine 125-labeled immunoglobulin G erythrocyte autoantibodies

    International Nuclear Information System (INIS)

    Masouredis, S.P.; Branks, M.J.; Garratty, G.; Victoria, E.J.

    1987-01-01

    The primary interaction of autoantibodies with red cells has been studied by using labeled autoantibodies. Immunoglobulin G red cell autoantibodies obtained from IgG antiglobulin-positive normal blood donors were labeled with radioactive iodine and compared with alloanti-D with respect to their properties and binding behavior. Iodine 125 -labeled IgG autoantibody migrated as a single homogeneous peak with the same relative mobility as human IgG on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The isoelectric focusing pattern of labeled autoantibodies varied from donor to donor but was similar to that of alloanti-D, consisting of multiple IgG populations with isoelectric points in the neutral to alkaline range. 125 I-autoantibody bound to all human red cells of common Rh phenotypes. Evidence for immunospecific antibody binding of the labeled autoantibody was based on variation in equilibrium binding to nonhuman and human red cells of common and rare phenotypes, enhanced binding after red cell protease modification, antiglobulin reactivity of cell-bound IgG comparable to that of cell-bound anti-D, and saturation binding in autoantibody excess. Scatchard analysis of two 125 I-autoantibody preparations yielded site numbers of 41,500 and 53,300 with equilibrium constants of 3.7 and 2.1 X 10(8) L X mol-1. Dog, rabbit, rhesus monkey, and baboon red cells were antigen(s) negative by quantitative adsorption studies adsorbing less than 3% of the labeled autoantibody. Reduced ability of rare human D--red blood cells to adsorb the autoantibody and identification of donor autoantibodies that bind to Rh null red blood cells indicated that eluates contained multiple antibody populations of complex specificities in contrast to anti-D, which consists of a monospecific antibody population. Another difference is that less than 70% of the autoantibody IgG was adsorbed by maximum binding red blood cells as compared with greater than 85% for alloanti-D

  3. Assessment of corrective factors for the LNHB reference measurement in terms of Kr air for iodine 125

    International Nuclear Information System (INIS)

    Gouriou, J.; Aubineau-Laniece, I.; Cutarella, D.; Plagnard, J.

    2010-01-01

    The LNHB (Laboratoire National Henri Becquerel) is currently developing a new primary reference for low dose rate curietherapy with iodine 125 in terms of reference kerma in air. This includes an innovative sensor: an ionization chamber with a toroidal air wall. The authors present Monte Carlo calculations performed for the determination of corrective factors to be applied to come down to reference conditions or to correct possible measurement errors. Calculations have been performed for the specific geometries of BEBIG sources which are used for ophthalmic and prostatic curietherapy treatments

  4. Measurement of the increase in the capillary permeability in skin with Evans blue labelled with iodine-125 or 131

    International Nuclear Information System (INIS)

    Sugarava, S.; Goncalves, J.M.

    1976-01-01

    The quantitative evaluation of bradykinin and histamine with Evans blue labelled with iodine -125 or 131 is described. The activity upon vascular permeability was performed in the abdominal wall of rats injecting intravenously solution of labelled Evans blue and 0,1 ml of vasoactive drugs solution intradermally. Skin discs were cut with circular punch for external counting, quantitative results being compared with control discs. By using this method, satisfactory log dose-reponse curves were obtained for bradykinin and histamine that followed the general trend of S - shaped curves [pt

  5. Chemisorption of iodine-125 to gold nanoparticles allows for real-time quantitation and potential use in nanomedicine

    Energy Technology Data Exchange (ETDEWEB)

    Walsh, Adrian A, E-mail: a.walsh@nanobiosols.com [Liverpool Science Park, Nano Biosols Ltd (United Kingdom)

    2017-04-15

    Gold nanoparticles have been available for many years as a research tool in the life sciences due to their electron density and optical properties. New applications are continually being developed, particularly in nanomedicine. One drawback is the need for an easy, real-time quantitation method for gold nanoparticles so that the effects observed in in vitro cell toxicity assays and cell uptake studies can be interpreted quantitatively in terms of nanoparticle loading. One potential method of quantifying gold nanoparticles in real time is by chemisorption of iodine-125, a gamma emitter, to the nanoparticles. This paper revisits the labelling of gold nanoparticles with iodine-125, first described 30 years ago and never fully exploited since. We explore the chemical properties and usefulness in quantifying bio-functionalised gold nanoparticle binding in a quick and simple manner. The gold particles were labelled specifically and quantitatively simply by mixing the two items. The nature of the labelling is chemisorption and is robust, remaining bound over several weeks in a variety of cell culture media. Chemisorption was confirmed as potassium iodide can remove the label whereas sodium chloride and many other buffers had no effect. Particles precoated in polymers or proteins can be labelled just as efficiently allowing for post-labelling experiments in situ rather than using radioactive gold atoms in the production process. We also demonstrate that interparticle exchange of I-125 between different size particles does not appear to take place confirming the affinity of the binding.

  6. Red cell autoantibodies characterized by competitive inhibition of iodine 125 Rh alloantibody binding and by immunoprecipitation of membrane proteins

    International Nuclear Information System (INIS)

    Pierce, S.W.; Victoria, E.J.; Masouredis, S.P.

    1990-01-01

    The relationship between determinants recognized by warm-type immunoglobulin G red cell autoantibodies and the Rh antigens was characterized by autoantibody competitive inhibition of iodine 125 Rh alloantibody binding and autoantibody immunoprecipitation of iodine 125 red blood cell membrane proteins. The majority of blood donor autoantibody recognized epitopes that are closely related to Rh antigens as determined by competitive inhibition studies. Eighteen of 20 (90%) autoantibodies inhibited anti-Rh(c) binding, 15 inhibited anti-Rh(E), 5 inhibited anti-Rh(D), and only 2 failed to inhibit any of the three Rh alloantibodies tested. Autoantibodies that inhibited anti-Rh(D) also inhibited anti-Rh(c) and anti-Rh(E) and all those that inhibited anti-Rh(E) also inhibited anti-Rh(c). Autoantibodies that inhibited all three Rh alloantibodies immunoprecipitated 30 kd membrane polypeptides, as did two of the three autoantibodies that inhibited only anti-Rh(c) and anti-Rh(E). One autoantibody in this group and two autoantibodies that inhibited only anti-Rh(c), as well as an autoantibody that did not inhibit any of the Rh alloantibodies, immunoprecipitated only a single membrane polypeptide identified as band 3. The majority of normal donor red blood cell autoantibodies inhibited the binding of Rh alloantibodies, which indicates that they either bound to the Rh polypeptides or to epitopes on band 3 that were closely associated with the Rh complex

  7. Use of iodine-125 brachytherapy in treatment of choroidal melanomas, technic and preliminary analysis of 78 patients

    International Nuclear Information System (INIS)

    Quetin, P.; Schumacher, C.; Schraub, S.; Meyer, L.; Polto, F.; Sahel, J.; Magnenet, P.; Andres, E.

    2001-01-01

    Purpose. - Iodine 125 curietherapy is one of the conservative treatments of uveal melanoma. The technique used to achieve these results was simplified through the physical characteristics of the radioelement and the optimized-dosimetry program employed. Patients and methods. - 78 patients with choroidal melanoma were treated with iodine 125. About 100 Gy were delivered to the superior pole of the tumour. The minimal length of follow-up was 17 months and the average, 67 months. Results. -There was 88% local control, leading to lowered visual acuity in 76 % of the cases. Radiation retinopathy, directly related to proximity to the macula, is the principle etiology. Seven patients died of hepatic metastasis, five patients were enucleated. Four patients were further treated with proton-therapy to make up for non-control locally. Conclusion. -One dose of 100 Gy to the superior pole of the tumor seemed to lead to good local control, with the exception of complications related to proximity to the macula and the optic nerve. In this attempt to optimize irradiation, the time lapse between any benefit in local control derived from irradiation and post-therapeutic complications observed remains insufficient to evaluate any relationship. (authors)

  8. Chemisorption of iodine-125 to gold nanoparticles allows for real-time quantitation and potential use in nanomedicine

    Science.gov (United States)

    Walsh, Adrian A.

    2017-04-01

    Gold nanoparticles have been available for many years as a research tool in the life sciences due to their electron density and optical properties. New applications are continually being developed, particularly in nanomedicine. One drawback is the need for an easy, real-time quantitation method for gold nanoparticles so that the effects observed in in vitro cell toxicity assays and cell uptake studies can be interpreted quantitatively in terms of nanoparticle loading. One potential method of quantifying gold nanoparticles in real time is by chemisorption of iodine-125, a gamma emitter, to the nanoparticles. This paper revisits the labelling of gold nanoparticles with iodine-125, first described 30 years ago and never fully exploited since. We explore the chemical properties and usefulness in quantifying bio-functionalised gold nanoparticle binding in a quick and simple manner. The gold particles were labelled specifically and quantitatively simply by mixing the two items. The nature of the labelling is chemisorption and is robust, remaining bound over several weeks in a variety of cell culture media. Chemisorption was confirmed as potassium iodide can remove the label whereas sodium chloride and many other buffers had no effect. Particles precoated in polymers or proteins can be labelled just as efficiently allowing for post-labelling experiments in situ rather than using radioactive gold atoms in the production process. We also demonstrate that interparticle exchange of I-125 between different size particles does not appear to take place confirming the affinity of the binding.

  9. Chemisorption of iodine-125 to gold nanoparticles allows for real-time quantitation and potential use in nanomedicine

    International Nuclear Information System (INIS)

    Walsh, Adrian A

    2017-01-01

    Gold nanoparticles have been available for many years as a research tool in the life sciences due to their electron density and optical properties. New applications are continually being developed, particularly in nanomedicine. One drawback is the need for an easy, real-time quantitation method for gold nanoparticles so that the effects observed in in vitro cell toxicity assays and cell uptake studies can be interpreted quantitatively in terms of nanoparticle loading. One potential method of quantifying gold nanoparticles in real time is by chemisorption of iodine-125, a gamma emitter, to the nanoparticles. This paper revisits the labelling of gold nanoparticles with iodine-125, first described 30 years ago and never fully exploited since. We explore the chemical properties and usefulness in quantifying bio-functionalised gold nanoparticle binding in a quick and simple manner. The gold particles were labelled specifically and quantitatively simply by mixing the two items. The nature of the labelling is chemisorption and is robust, remaining bound over several weeks in a variety of cell culture media. Chemisorption was confirmed as potassium iodide can remove the label whereas sodium chloride and many other buffers had no effect. Particles precoated in polymers or proteins can be labelled just as efficiently allowing for post-labelling experiments in situ rather than using radioactive gold atoms in the production process. We also demonstrate that interparticle exchange of I-125 between different size particles does not appear to take place confirming the affinity of the binding.

  10. Physical basics and clinical realization of interstitial brachytherapy of the prostate with iodine 125

    International Nuclear Information System (INIS)

    Kaulich, T.W.; Nuesslin, F.; Lamprecht, U.; Bamberg, M.; Paulsen, F.; Loeser, W.; Bichler, K.H.; Kahmann, F.; Henkel, T.O.; Maurer, U.

    2002-01-01

    Background: Interstitial brachytherapy with I-125 seeds can be used for successful treatment of early stage prostate cancer. There is presented the technique of permanent transperineal implantation of I-125 seeds with intraoperative treatment planning which is suited for the treatment of prostate cancer up to the clinical stage of T2a. Material and methods: Some weeks before the implantation of the seeds the prostate volume is determined using transrectal ultrasound (TRUS) so as to estimate the required number of I-125 seeds. At the outset of the treatment the prostate is stabilized by two perineally inserted needles. Subsequently there is carried out an ultrasound guide treatment planning that allows to optimize the distribution of the seeds within the prostate. In interstitial brachytherapy we use RAPID STRANDs trademark , i.e. the I-125 seeds are embedded in vicryl suture at distances of 1 cm. During implantation of the I-125 seeds the transversal placement of the applicator needles is controlled by TRUS and the cranio-caudal placement of the applicator needles is controlled using the fluoroscopic unit as well as TRUS. About 4 weeks after the implantation of the seeds there is carried out a postoperative computation of the dose distribution of the implant using CT imaging. Results: The procedure possesses the advantage that ultrasound imaging, treatment planning and seed implantation are carried out with the prostate remaining in an unaltered position. During implantation the combined imaging of TRUS and fluoroscopy allows a safe placement of the seeds within the prostate. Conclusion: The methods for the calculation of the actually attained dose distribution must still be optimized, because the postoperative examination of the individual results has so far been possible only with difficulties resulting from methodological inconveniences. (orig.) [de

  11. Considerações radiodosimétricas da braquiterapia ocular com iodo-125 e rutênio/ródio-106 Radiodosimetric considerations on ocular brachytherapy with iodine-125 and ruthenium/rhodium-106

    Directory of Open Access Journals (Sweden)

    Arnaldo Prata Mourão

    2009-02-01

    the spatial distribution of doses generated by beta particles and photons. The simulations demonstrated that the utilization of iodine 125 seeds implies a high dose to the crystalline lens, while ruthenium/rhodium-106 results in high dose on the sclera surface. CONCLUSION: The dose to the crystalline lens depends on the tumor position and thickness, the plaque diameter, and the radionuclide utilized. In the present study, the ruthenium/rhodium-106 source is recommended for low tumor thickness. Irradiation with iodine-125 results in higher doses to the crystalline lens than irradiation with ruthenium/rhodium-106. The maximum value for dose to the crystalline lens corresponds to 12.75% of the maximum dose with iodine-125 and only 0.005% for ruthenium/rhodium-106.

  12. Biodistribution and dosimetric study in medullary thyroid cancer xenograft using bispecific antibody and iodine-125-labeled bivalent hapten.

    Science.gov (United States)

    Hosono, M; Hosono, M N; Kraeber-Bodéré, F; Devys, A; Thédrez, P; Fiche, M; Gautherot, E; Barbet, J; Chatal, J F

    1998-09-01

    The purpose of this study was to evaluate biodistributions and absorbed doses of anti-carcinoembryonic antigen (CEA)/anti-diethylenetriamine pentaacetic acid (DTPA)-indium (anti-DTPA-In) bispecific monoclonal antibody (BsMAb) F6-734 and 125I-labeled DTPA-indium dimer hapten (125I-di-DTPA-In hapten) in athymic mice xenografted with human medullary thyroid cancer. Bispecific monoclonal antibodies F6-679 (anti-CEA/antihistamine) and G7A5-734 (antimelanoma/anti-di-DTPA-In) were used as irrelevant BsMAbs. Athymic mice inoculated with TT medullary thyroid cancer cells expressing CEA were administered BsMAbs F6-734, F6-679 or G7A5-734 and then, 48 hr later, 125I-di-DTPA-In hapten. Iodine-125-labeled F6 F(ab')2 fragment was injected into other groups of mice. Biodistributions were examined at 30 min and 5, 24, 48 and 96 hr after injection of 125I-di-DTPA-In hapten or 125I-labeled F6 F(ab')2. In mice injected with BsMAb F6-734 and 125I-di-DTPA-In hapten, tumor uptake was 9.1%+/-2.1%, 8.7%+/-3.5%, 8.0%+/-2.3%, 5.1%+/-0.9% and 3.5%+/-1.5% of the injected dose/g at 30 min and 5, 24, 48 and 96 hr, and tumor-to-blood, tumor-to-liver and tumor-to-kidney ratios were 37.0+/-12.5, 32.3+/-10.9 and 10.4+/-2.7 at 24 hr. Iodine-125-F6 F(ab')2 fragment showed a tumor uptake of 7.39% injected dose/g and tumor-to-blood, tumor-to-liver and tumor-to-kidney ratios of 1.8+/-0.6, 7.3+/-2.9 and 3.6+/-1.6 at 24 hr. In mice injected with F6-679 or G7A5-734, tumor uptake and tumor-to-normal tissue ratios were much lower than in the mice injected with F6-734. These results were confirmed by autoradiographic studies that demonstrated clear tumor-to-normal tissue contrast. This two-step targeting method seems very potent for the diagnosis and therapy of human medullary thyroid cancer and other CEA-producing tumors because it combines high tumor uptake and low normal tissue background.

  13. Injectable iodine-125 labeled tissue marker for radioactive localization of non-palpable breast lesions

    DEFF Research Database (Denmark)

    Schaarup-Jensen, Henrik; Jensen, Andreas Ingemann; Hansen, Anders Elias

    2018-01-01

    We have developed a 125I-radiolabeled injectable fiducial tissue marker with the potential to replace current methods used for surgical guidance of non-palpable breast tumors. Methods in routine clinical use today such as radioactive seed localization, radio-guided occult lesion localization....... Biodistribution studies show that there is negligible radioactivity in all non-tumor tissues sampled, with the exception of the thyroid gland, where limited accumulation was observed (0.06% of injected dose after 7 days). Based on the excellent performance of the marker and the fact that it can be delivered...... through thin hypodermic needles (≥27G), the marker holds great promise for clinical application, since patient discomfort is reduced significantly compared to current methods. Statement of Significance. A new type of tissue marker for local administration to non-palpable breast tumors has been developed...

  14. Flask sealing on in vitro seed germination and morphogenesis of two types of ornamental pepper explants

    Directory of Open Access Journals (Sweden)

    Diego Silva Batista

    Full Text Available ABSTRACT: The influence of flask sealing and explant source on the in vitro morphogenesis of pepper, were evaluated in Capsicum annuum. Seeds were sterilized and inoculated in Murashige and Skoog media supplemented with vitamins, myo-inositol, sucrose, and agar. Gas exchange was evaluated in the germination stage by comparing 3 flask-sealing systems: rigid polypropylene lids (PLs without vents, PLs with 1 vent, and PLs with 2 vents covered with membranes. In the regeneration stage, cotyledon and hypocotyl segments were transferred to the organogenesis-inducing media, being the different sealing types also tested in a factorial scheme. Photosynthetic pigments, morphological and hystological analyses were conducted for each treatment. Plants maintained in glass flasks capped with vented lids showed more vigorous growth and differentiated anatomical structures. These treatments resulted in taller plants, higher numbers and more expanded leaves, higher fresh and dry weights, and an increase in photosynthetic pigments. Cultivation of C. annuum in flasks with reduced gas exchange was more effective on callus induction. During the regeneration stage, hypocotyls were more effective than cotyledons. Sealing type influenced the morphogenic responses of pepper, demonstrating that an increase in gas exchange has a positive effect on biomass production and acclimatization of the plantlets.

  15. Relation of immediate and delayed thallium-201 distribution to localization of iodine-125 antimyosin antibody in acute experimental myocardial infarction

    International Nuclear Information System (INIS)

    Khaw, B.A.; Strauss, H.W.; Pohost, G.M.; Fallon, J.T.; Katus, H.A.; Haber, E.

    1983-01-01

    Thallium-201 (TI-201) distribution in acute experimental myocardial infarction (MI) (n . 18) was compared with cardiac-specific antimyosin Fab (AM-Fab) uptake, a specific marker for myocardial necrosis. When antimyosin was injected 4 hours after ligation with TI-201 administered 23 hours 55 minutes later and measurement of myocardial distribution determined 5 minutes after intravenous administration of TI-201, (1) TI-201 distribution closely correlated with microsphere regional blood flow, and (2) an inverse exponential relation to iodine-125 (I-125) AM-Fab uptake was apparent. In another group of 4 animals, TI-201 and AM-Fab were administered intravenously 4 hours after MI, and 36 hours later myocardial distribution was measured. This delayed TI-201 distribution had a close inverse linear correlation with I-125 AM-Fab uptake. This inverse linear relation also was apparent in 28-hour-old MIs in dogs (n . 4) where collateral circulation had been established. TI-201 was administered intravenously at 27 hours after MI, and TI-201 distribution was determined 1 hour later. The present study demonstrated that whereas immediate TI-201 distribution is flow-limited, delayed TI-201 distribution is a marker of cell viability which, due to prolonged circulation time and redistribution, is not flow-limited

  16. Relationship between two year PSA nadir and biochemical recurrence in prostate cancer patients treated with iodine-125 brachytherapy

    Directory of Open Access Journals (Sweden)

    Carlos Antônio da Silva Franca

    2014-04-01

    Full Text Available Objective To evaluate the relationship between two year PSA nadir (PSAn after brachytherapy and biochemical recurrence rates in prostate cancer patients. Materials and Methods In the period from January 1998 to August 2007, 120 patients were treated with iodine-125 brachytherapy alone. The results analysis was based on the definition of biochemical recurrence according to the Phoenix Consensus. Results Biochemical control was observed in 86 patients (71.7%, and biochemical recurrence, in 34 (28.3%. Mean PSAn was 0.53 ng/ml. The mean follow-up was 98 months. The patients were divided into two groups: group 1, with two year PSAn < 0.5 ng/ml after brachytherapy (74 patients; 61.7%, and group 2, with two year PSAn ≥ 0.5 ng/ml after brachytherapy (46 patients; 38.3%. Group 1 presented biochemical recurrence in 15 patients (20.3%, and group 2, in 19 patients (43.2% (p < 0.02. The analysis of biochemical disease-free survival at seven years, stratified by the two groups, showed values of 80% and 64% (p < 0.02, respectively. Conclusion Levels of two year PSAn ≥ 0.5 ng/ml after brachytherapy are strongly correlated with a poor prognosis. This fact may help to identify patients at risk for disease recurrence.

  17. Quantification of the simple and double strand breaks following the disintegration of iodine-125 in situ in chromosomal fiber

    International Nuclear Information System (INIS)

    Oudira, H.; Saifi, A.

    2010-01-01

    The principal objective of this study is to compare the radiochemical yields of the simple and double strand breaks (C.S.B. and C.D.B.) generated in the propellers of the molecule of DNA, following the taking in consideration of two electronic spectra of disintegration of iodine-125. Indeed, the combined use of the Monte Carlo method of the type step by step and the equation of diffusion (∂ C i / ∂ t = D i Δ 2 C i + S) makes it possible to simulate the transport of the electrons, and the chemical reactions due to the diffusion of the entities created throughout the physico-chemical and chemical process considered (e-aq, H, OH, H 2 , H 2 O 2 , and H 3 O + ). In this study, we take in consideration a complex model of DNA (nucleosome) and its envelope of hydration like we also take in consideration of the radio-protector effect of the inhibitors such as the Formiat (Formiat the sodium, HCOO - ). Moreover, the comparison of our results to those obtained by other models, highlights on one hand an unquestionable agreement and on the other hand the power and the capacity of adaptation of the codes worked out to various models of DNA. (authors)

  18. Long-Term Results of Brachytherapy With Temporary Iodine-125 Seeds in Children With Low-Grade Gliomas

    International Nuclear Information System (INIS)

    Korinthenberg, Rudolf; Neuburger, Daniela; Trippel, Michael; Ostertag, Christoph; Nikkhah, Guido

    2011-01-01

    Purpose: To retrospectively review the results of temporary I-125 brachytherapy in 94 children and adolescents with low-grade glioma. Methods and Materials: Treatment was performed in progressive tumors roughly spherical in shape with a diameter of up to 5 cm, including 79 astrocytomas, 5 oligodendrogliomas, 4 oligoastrocytomas, 1 ependymoma, and 5 other tumors. Location was suprasellar/chiasmal in 44, thalamic/basal ganglia in 18, hemispheric in 15, midbrain/pineal region in 13, and lower brainstem in 3. Initially, 8% of patients were free of symptoms, 47% were symptomatic but not disabled, and 30% were slightly, 6% moderately, and 3% severely disabled. Results: 5- and 10-year survival was 97% and 92%. The response to I-125 brachytherapy over the long term was estimated after a median observation period of 38.4 (range, 6.4-171.0) months. At that time, 4 patients were in complete, 27 in partial, and 18 in objective remission; 15 showed stable and 30 progressive tumors. Treatment results did not correlate with age, sex, histology, tumor size, location, or demarcation of the tumor. Secondary treatment became necessary in 36 patients, including 19 who underwent repeated I-125 brachytherapy. At final follow-up, the number of symptom-free patients had risen to 21%. Thirty-eight percent showed symptoms without functional impairment, 19% were slightly and 11% moderately disabled, and only 4% were severely disabled. Conclusions: Response rates similar to those of conventional radiotherapy or chemotherapy can be anticipated with I-125 brachytherapy in tumors of the appropriate size and shape. We believe it to be a useful contribution to the treatment of low-grade gliomas in children.

  19. Seals

    International Nuclear Information System (INIS)

    Welsher, R.A.G.

    1982-01-01

    An aperture through a biological shield is sealed by a flexible sheath having a beading at one end located on an annular member slidable in the aperture such that the beading bears in sealing engagement against the sides of the aperture. The annular member is retained by a retractable latch and can be rejected by pushing it out of the aperture using a replacement annular member with a replacement sheath thereon to butt against the annular member to be rejected. The replacement annular member may be mounted on a tubular device having an outer co-axial member for operating the latch when the replacement annular member butts against the annular member to be rejected. Applications include effecting a seal between a remote handling equipment and a wall through which the equipment extends. (author)

  20. Iodine 125 prostate brachytherapy: prognostic factors for long-term urinary, digestive and sexual toxicities

    International Nuclear Information System (INIS)

    Doyen, J.; Mohammed Ali, A.; Ginot, A.; Ferre, M.; Castelli, J.; Hannoun-Levi, J.M.; Chamorey, E.; Mohammed Ali, A.; Quintens, H.; Amiel, J.

    2009-01-01

    .4 %) presented a sexual toxicity; 26.9 % (49 patients) and 5 % (nine patients) were scored as grade 2 and 3 respectively. A number of seeds greater than 75 (p = 0.032) and S grade greater than or equal to 2 (p < 0.0001) were recognized as prognostic factors in U.V.A.. S grade was the only prognostic factor in M.V.A. (p 0.0015). Conclusion The duration of U, D and S toxicity is strongly correlated with a high number of toxicities and the grade of toxicity. This analysis allows for better information given to the patient regarding the duration of the post-treatment complications

  1. In vivo imaging of insulin receptors by PET: preclinical evaluation of iodine-125 and iodine-124 labelled human insulin

    International Nuclear Information System (INIS)

    Iozzo, P.; Osman, S.; Glaser, M.; Knickmeier, M.; Ferrannini, E.; Pike, V.W.; Camici, P.G.; Law, M.P.

    2002-01-01

    [A 14 -*I]iodoinsulin was prepared for studies to assess the suitability of labeled iodoinsulin for positron emission tomography (PET). Iodine-125 was used to establish the methods and for preliminary studies in rats. Further studies and PET scanning in rats were carried out using iodine-124. Tissue and plasma radioactivity was measured as the uptake index (UI={cpm·(g tissue) -1 }/{cpm injected·(g body weight) -1 }) at 1 to 40 min after intravenous injection of either [A 14 - 125 I]iodoinsulin or [A 14 - 124 I]iodoinsulin. For both radiotracers, initial clearance of radioactivity from plasma was rapid (T 1/2 ∼ 1 min), reaching a plateau (UI = 2.8) at ∼ 5 min which was maintained for 35 min. Tissue biodistributions of the two radiotracers were comparable; at 10 min after injection, UI for myocardium was 2.4, liver, 4.0, pancreas, 5.4, brain, 0.17, kidney, 22, lung, 2.3, muscle, 0.54 and fat, 0.28. Predosing rats with unlabelled insulin reduced the UI for myocardium (0.95), liver (1.8), pancreas (1.2) and brain (0.08), increased that for kidney (61) but had no effect on that for lung (2.5), muscle (0.50) or fat (0.34). Analysis of radioactivity in plasma demonstrated a decrease of [ 125 I]iodoinsulin associated with the appearance of labeled metabolites; the percentage of plasma radioactivity due to [ 125 I]iodoinsulin was 40% at 5 min and 10% at 10 min. The heart, liver and kidneys were visualized using [ 124 I]iodoinsulin with PET

  2. Dosimetric and Late Radiation Toxicity Comparison Between Iodine-125 Brachytherapy and Stereotactic Radiation Therapy for Juxtapapillary Choroidal Melanoma

    Energy Technology Data Exchange (ETDEWEB)

    Krema, Hatem, E-mail: htmkrm19@yahoo.com [Department of Ocular Oncology, Princess Margaret Hospital/University Health Network, University of Toronto, Toronto, Ontario (Canada); Heydarian, Mostafa [Department of Radiation Medicine, Princess Margaret Hospital/University Health Network, University of Toronto, Toronto, Ontario (Canada); Beiki-Ardakani, Akbar [Department of Radiation Oncology, Princess Margaret Hospital/University Health Network, University of Toronto, Toronto, Ontario (Canada); Weisbrod, Daniel [Department of Ocular Oncology, Princess Margaret Hospital/University Health Network, University of Toronto, Toronto, Ontario (Canada); Xu, Wei [Department of Biostatistics, Princess Margaret Hospital/University Health Network, University of Toronto, Toronto, Ontario (Canada); Laperriere, Normand J.; Sahgal, Arjun [Department of Radiation Oncology, Princess Margaret Hospital/University Health Network, University of Toronto, Toronto, Ontario (Canada)

    2013-07-01

    Purpose: To compare the dose distributions and late radiation toxicities for {sup 125}I brachytherapy (IBT) and stereotactic radiation therapy (SRT) in the treatment of juxtapapillary choroidal melanoma. Methods: Ninety-four consecutive patients with juxtapapillary melanoma were reviewed: 30 have been treated with IBT and 64 with SRT. Iodine-125 brachytherapy cases were modeled with plaque simulator software for dosimetric analysis. The SRT dosimetric data were obtained from the Radionics XKnife RT3 software. Mean doses at predetermined intraocular points were calculated. Kaplan-Meier estimates determined the actuarial rates of late toxicities, and the log–rank test compared the estimates. Results: The median follow-up was 46 months in both cohorts. The 2 cohorts were balanced with respect to pretreatment clinical and tumor characteristics. Comparisons of radiation toxicity rates between the IBT and SRT cohorts yielded actuarial rates at 50 months for cataracts of 62% and 75% (P=.1), for neovascular glaucoma 8% and 47% (P=.002), for radiation retinopathy 59% and 89% (P=.0001), and for radiation papillopathy 39% and 74% (P=.003), respectively. Dosimetric comparisons between the IBT and SRT cohorts yielded mean doses of 12.8 and 14.1 Gy (P=.56) for the lens center, 17.6 and 19.7 Gy (P=.44) for the lens posterior pole, 13.9 and 10.8 Gy (P=.30) for the ciliary body, 61.9 and 69.7 Gy (P=.03) for optic disc center, and 48.9 and 60.1 Gy (P<.0001) for retina at 5-mm distance from tumor margin, respectively. Conclusions: Late radiation-induced toxicities were greater with SRT, which is secondary to the high-dose exposure inherent to the technique as compared with IBT. When technically feasible, IBT is preferred to treat juxtapapillary choroidal melanoma.

  3. Effect of cultural conditions on the seed-to-seed growth of Arabidopsis and Cardamine - A study of growth rates and reproductive development as affected by test tube seals

    Science.gov (United States)

    Hoshizaki, T.

    1982-01-01

    The effects of test tube seals on the growth, flowering, and seed pod formation of Arabidopsis thaliana (L.) Heynh., mouse ear cress, and Cardamine oligosperma Nutt, bitter cress, are studied in order to assess the conditions used in weightlessness experiments. Among other results, it is found that the growth (height) and flowering (date of bud appearance) were suppressed in mouse ear cress in tubes sealed with Saran. Seed pod formation which occurred by day 45 in open-to-air controls, was still lacking in the sealed plants even up to day 124. The growth and flowering of bitter cress were also suppressed by the Saran seal, although up to day 55 the Saran-sealed plants were taller. It is suggested that atmospheric composition was the cause of the suppression of growth, flowering, and seed pod development in these plants, since the mouse ear cress renewed their growth and then set seed pods after the Saran seal was ruptured.

  4. Obtention of brachytherapy seeds by sealing process using polymer; Obtencao de sementes de braquiterapia pelo processo de selagem com polimero

    Energy Technology Data Exchange (ETDEWEB)

    Lana, Diogo Alberto P.D.; Ferraz, Wilmar B.; Santos, Ana Maria M., E-mail: amms@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil); Carvalho, Luiz Claudio F.M. Garcia [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil)

    2012-08-15

    Brachytherapy is an advanced cancer treatment where radioactive seeds or sources are placed near or directly into the tumor thus reducing the radiation exposure in the surrounding healthy tissues. Several kinds of seeds have been developed in order to obtain a better dose distribution around them and with a lower cost manufacturing. These seeds consist of an encapsulation (titanium or stainless steel tube), a radionuclide carrier, and X-ray marker. The usual sealing process of the seeds is done with laser welding, but this process can promote radionuclide volatilization. In this paper, we present a new sealing process using epoxy resin and characterizations of two epoxy resins. These resins were characterized by Fourier transform infrared spectroscopic (FTIR), ultraviolet-visible spectroscopy (UV-vis) and differential scanning calorimetry (DSC). Interactions of the resins and of the sealed seeds in a simulated body fluid (SBF) were evaluated by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), and by a counting gamma-rays. (author)

  5. Iodine-125 in the fresh water environment in England; measurements along the pathway from sewage discharge to thyroid glands and determinations of absorbed dose to humans

    International Nuclear Information System (INIS)

    Howe, J.R.; Bowlt, C.

    1992-01-01

    Iodine-125 has been measured in the fresh water supply in England, particularly in the Thames Valley. 125 I discarded into the sewage drainage system, travels in the liquid effluent into rivers. When mains water is abstracted downstream from such discharges low levels of 125 I ( 125 I. However it was never possible to establish more than a semi-quantitative relationship between their activity levels and those of their surroundings. In general, levels of 125 I have shown a 3-4 fold increase in the fresh water environment during the 1980's. (Author)

  6. The Efficacy and Safety of Iodine-125 Brachytherapy Combined with Chemotherapy in Treatment of Advanced Lung Cancer: A Meta-Analysis

    International Nuclear Information System (INIS)

    Qiu, H.; Wang, J.; Ji, J.; Ma, G.; Zhang, L.; Shao, Z.

    2017-01-01

    The aim of this study was to systematically review the efficacy and safety of iodine-125 brachytherapy combined with chemotherapy in patients with advanced lung cancer. PubMed, MEDLINE, EBSCO, FMJS and Web of Science were searched to obtain randomized controlled trials (RCTs), published in English and Chinese, until February 2016. The evaluating indicators were complete response (CR), partial response (PR), stable disease (SD), progressive disease (PD), overall response rate (ORR), disease control rate (DCR), one-year overall survival, two-year overall survival and adverse events. Revman 5.2 software was used for data syntheses and analyses. A total of 296 patients enrolled in 5 RCTs were ultimately included in this study based on our selection criteria, and 150 patients received chemotherapy alone, while another 146 patients received the combination therapy of iodine-125 brachytherapy and chemotherapy. The results showed that iodine-125 brachytherapy combined with chemotherapy was superior to chemotherapy alone in CR (risk ratio [RR] = 3.66, 95% confidence interval [CI]: 2.08 to 6.44, p<0.001), PR (RR = 1.47, 95% CI: 1.16 to 1.86, p=0.001), ORR (RR = 1.85, 95% CI: 1.54 to 2.22, p<0.001), DCR (RR = 1.19, 95% CI: 1.10 to 1.29, p<0.001), one-year overall survival (RR = 1.46, 95% CI: 1.12 to 1.92, p=0.006) and PD (RR = 0.20, 95% CI: 0.09 to 0.43, p<0.001); meanwhile, there was no significant difference in two-year overall survival (RR = 1.30, 95% CI: 0.72 to 2.37, p=0.39). In terms of adverse events, the combination therapy significantly increased the incidence of pneumothorax (RR = 4.93, 95% CI: 1.94 to 12.55, p=<0.001); however, no significant differences were found in the incidence of other adverse events. This study indicated that the combination therapy of iodine-125 brachytherapy and chemotherapy could improve the therapeutic efficacy of advanced lung cancer without increasing the incidence of adverse events, except pneumothorax. (author)

  7. Study of dosimetric parameters for iodine-125 brachytherapy sources development from IPEN-CNEN/SP using Monte Carlo method

    International Nuclear Information System (INIS)

    Oliveira, Tiago Batista de

    2016-01-01

    Expectations of the World Health Organization for the year 2030 are that the number of cancer deaths is approximately 13.2 million, reflecting the high proportion of this disease in global health issue. With respect to prostate cancer, according to the National Cancer Institute, the number of cases diagnosed worldwide in 2012 was approximately 1.1 million, while in Brazil the data demonstrated the incidence of 68,000 new cases. The treatment of cancer can be performed with surgery (prostatectomy) or radiation therapy. Among radiotherapy, we can highlight the brachytherapy technique, which consists in the introduction of small radioactive sources (seeds) within the prostate, which is delivered a high dose value in the treatment volume and low dose in the surrounding tissues. In Brazil, the medical profession estimates a demand of approximately 8000 seeds / month, and the unit cost of each seed at least US $ 26.00. The AAPM protocol TG-43 recommend the dose-rate constant, radial dose function and anisotropy function for dosimetric analysis LDR brachytherapy seeds. In this work, Monte Carlo simulations were performed in order to assess the dosimetric parameters of the OncoSeed-6711, manufactured by Oncura-GEHealthcare, and a seed developed by Radiation Technology Center, using the MCNP5 code. A 6711 seed, an IPEN seed and the 30 x 30 x 30cm 3 phantom filled with water were modeled to simulate the dose distribution. The 6711 seed parameters were compared with literature, and the results presented relative error less than 0.1% for Λ. In comparison with the 6711 seed, the IPEN model seed dosimetric parameters were similar, account the statistical uncertainty. (author)

  8. Iodine 125 Brachytherapy With Vitrectomy and Silicone Oil in the Treatment of Uveal Melanoma: 1-to-1 Matched Case-Control Series

    Energy Technology Data Exchange (ETDEWEB)

    McCannel, Tara A., E-mail: TMcCannel@jsei.ucla.edu; McCannel, Colin A.

    2014-06-01

    Purpose: We initially reported the radiation-attenuating effect of silicone oil 1000 centistokes for iodine 125. The purpose of this report was to compare the clinical outcomes in case patients who had iodine 125 brachytherapy with vitrectomy and silicone oil 1000 centistokes with the outcomes in matched control patients who underwent brachytherapy alone. Methods and Materials: Consecutive patients with uveal melanoma who were treated with iodine 125 plaque brachytherapy and vitrectomy with silicone oil with minimum 1-year follow-up were included. Control patients who underwent brachytherapy alone were matched for tumor size, location, and sex. Baseline patient and tumor characteristics and tumor response to radiation, final visual acuity, macular status, central macular thickness by ocular coherence tomography (OCT), cataract progression, and metastasis at last follow-up visit were compared. Surgical complications were also determined. Results: Twenty case patients met the inclusion criteria. The average follow-up time was 22.1 months in case patients and 19.4 months in control patients. The final logMAR vision was 0.81 in case patients and 1.1 in control patients (P=.071); 8 case patients and 16 control patients had abnormal macular findings (P=.011); and the average central macular thickness by OCT was 293.2 μm in case patients and 408.5 μm in control patients (P=.016). Eleven case patients (55%) and 1 control patient (5%) had required cataract surgery at last follow-up (P=.002). Four patients in the case group and 1 patient in the control group experienced metastasis (P=.18). Among the cases, intraoperative retinal tear occurred in 3 patients; total serous retinal detachment and macular hole developed in 1 case patient each. There was no case of rhegmatogenous retinal detachment, treatment failure, or local tumor dissemination in case patients or control patients. Conclusions: With up to 3 years of clinical follow-up, silicone oil during brachytherapy

  9. Iodine 125 Brachytherapy With Vitrectomy and Silicone Oil in the Treatment of Uveal Melanoma: 1-to-1 Matched Case-Control Series

    International Nuclear Information System (INIS)

    McCannel, Tara A.; McCannel, Colin A.

    2014-01-01

    Purpose: We initially reported the radiation-attenuating effect of silicone oil 1000 centistokes for iodine 125. The purpose of this report was to compare the clinical outcomes in case patients who had iodine 125 brachytherapy with vitrectomy and silicone oil 1000 centistokes with the outcomes in matched control patients who underwent brachytherapy alone. Methods and Materials: Consecutive patients with uveal melanoma who were treated with iodine 125 plaque brachytherapy and vitrectomy with silicone oil with minimum 1-year follow-up were included. Control patients who underwent brachytherapy alone were matched for tumor size, location, and sex. Baseline patient and tumor characteristics and tumor response to radiation, final visual acuity, macular status, central macular thickness by ocular coherence tomography (OCT), cataract progression, and metastasis at last follow-up visit were compared. Surgical complications were also determined. Results: Twenty case patients met the inclusion criteria. The average follow-up time was 22.1 months in case patients and 19.4 months in control patients. The final logMAR vision was 0.81 in case patients and 1.1 in control patients (P=.071); 8 case patients and 16 control patients had abnormal macular findings (P=.011); and the average central macular thickness by OCT was 293.2 μm in case patients and 408.5 μm in control patients (P=.016). Eleven case patients (55%) and 1 control patient (5%) had required cataract surgery at last follow-up (P=.002). Four patients in the case group and 1 patient in the control group experienced metastasis (P=.18). Among the cases, intraoperative retinal tear occurred in 3 patients; total serous retinal detachment and macular hole developed in 1 case patient each. There was no case of rhegmatogenous retinal detachment, treatment failure, or local tumor dissemination in case patients or control patients. Conclusions: With up to 3 years of clinical follow-up, silicone oil during brachytherapy

  10. Development of irradiation support devices for production of brachytherapy seeds

    Energy Technology Data Exchange (ETDEWEB)

    Mattos, Fabio R.; Rostelato, Maria Elisa C.M.; Zeituni, Carlos A.; Souza, Carla D.; Moura, Joao A.; Peleias Junior, Fernando S.; Karan Junior, Dib; Feher, Anselmo; Oliveira, Tiago B.; Benega, Marcos A.G., E-mail: tiagooliveira298@gmail.com, E-mail: mattos.fr@gmail.com, E-mail: elisaros@ipen.br, E-mail: czeituni@ipen.br, E-mail: carladdsouza@yahoo.com.br, E-mail: jamoura@ipen.br, E-mail: ernandopeleias@gmail.com, E-mail: s, E-mail: dib.karan@usp.br, E-mail: afeher@ipen.br, E-mail: marcosagbenega@gmail.com [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2013-07-01

    Ophthalmic tumors treatment with brachytherapy sources has been widely used as a primary or secondary therapy for non-malignant or malignant tumors, for example, choroid melanoma, and retinoblastoma. Ruthenium-106, Iodine-125, Palladium -103, Gold-198 and Iridium-192, are some radionuclides that can be applied for treatment of ocular tumors. These sources are in small sizes (a few millimeters) and different shapes (rods, wires, disks). To ensure high accuracy during treatment, they are positioned in eye applicators, specially designed to fit on the surface of tumor. The Nuclear and Energy Research Institute (IPEN/CNEN) in a partnership with Paulista Medicine School (UNIFESP) created a project that aims to develop a prototype of Iridium-192 seeds for treatment of eye cancer. This seed consists in a core of Ir -Pt alloy (20%-80%) with a length of 3 mm, to be activated in IPEN's IEA-R1 Reactor, and a titanium capsule sealing the core. It was imperative to develop a sustainer device for irradiation. This piece is used to avoid overlapping of one cores and, therefore, avoiding the 'shadow effect' that does not allow full activation of each core due to the high density. (author)

  11. Development of irradiation support devices for production of brachytherapy seeds

    International Nuclear Information System (INIS)

    Mattos, Fabio R.; Rostelato, Maria Elisa C.M.; Zeituni, Carlos A.; Souza, Carla D.; Moura, Joao A.; Peleias Junior, Fernando S.; Karan Junior, Dib; Feher, Anselmo; Oliveira, Tiago B.; Benega, Marcos A.G.

    2013-01-01

    Ophthalmic tumors treatment with brachytherapy sources has been widely used as a primary or secondary therapy for non-malignant or malignant tumors, for example, choroid melanoma, and retinoblastoma. Ruthenium-106, Iodine-125, Palladium -103, Gold-198 and Iridium-192, are some radionuclides that can be applied for treatment of ocular tumors. These sources are in small sizes (a few millimeters) and different shapes (rods, wires, disks). To ensure high accuracy during treatment, they are positioned in eye applicators, specially designed to fit on the surface of tumor. The Nuclear and Energy Research Institute (IPEN/CNEN) in a partnership with Paulista Medicine School (UNIFESP) created a project that aims to develop a prototype of Iridium-192 seeds for treatment of eye cancer. This seed consists in a core of Ir -Pt alloy (20%-80%) with a length of 3 mm, to be activated in IPEN's IEA-R1 Reactor, and a titanium capsule sealing the core. It was imperative to develop a sustainer device for irradiation. This piece is used to avoid overlapping of one cores and, therefore, avoiding the 'shadow effect' that does not allow full activation of each core due to the high density. (author)

  12. Combination of bilateral pelvic lymphadenectomy, permanent iodine-125 implantation, and percutaneous irradiation of the locally confined prostatic cancer. Pt. 1

    International Nuclear Information System (INIS)

    Thiel, H.J.; Mueller, R.; Schrott, K.M.; Erlangen-Nuernberg Univ., Erlangen; Erlangen-Nuernberg Univ., Erlangen

    1987-01-01

    Since the beginning of 1981, 32 patients at an age of 52 to 72 years who suffered from a locally confined adenocarcinoma of the prostate were treated by permanent implantation of I-125 seeds. 25 patients were evaluated after a median observation period of 30 months. The first group consisting of 19 patients was submitted to a combined percutaneous and interstitial treatment, the other 6 patients were initially treated only by interstitial therapy because of severe complications observed in the meantime. After bilateral pelvic staging lymphadenectomy, permanent I-125 seeds were implanted into the patients of stage T 1 , T 2 , early T 3 and pN 0-1 , in case of microscopic lymph node manifestation without capsular perforation also into patients of stage pN 2 and pN 4 . 8 weeks later the patients received a moving beam irradiation with 10 MV photons at the linear accelerator. The centre of the prostate was faded out by a specially constructed H absorber in such a way that the prescribed target dose of 36 Gy in 4 weeks to the 90%-isodose was only applied to a spherical surface around the implant. 1 patient died perioperatively from an embolism due to phlebothrombosis of the thigh. 22 out of the other 24 patients are in complete remission, 1 patient had a local recurrence in the right seminal vesicle which appeared 28 months after primary therapy, and 1 patient developed skeletal metastases. The objective side effects and late complications of our combined treatment are considerable with respect to their incidence as well as their severity: a slight or medium radioproctitis was found after a latent period of 1 to 2 years in 28% (5/18) of cases, after a latent time of about 1 1/2 to 2 years another 28% (5/18) developed subsequently to a proctitis an urethral stricture and an ulcer situated on the anterior rectum wall facing the prostate, and 4 patients presented finally a prostato-rectal fistula. (orig.) [de

  13. Film dosimetry analyses on the effect of gold shielding for Iodine-125 eye plaque therapy for choroidal melanoma

    Energy Technology Data Exchange (ETDEWEB)

    Wu, A. (Department of Radiation Oncology, University of Pittsburgh, School of Medicine, Joint Radiation Oncology Center and Pittsburgh Cancer Institute, Pittsburgh, PA (USA)); Krasin, F. (Department of Radiation Oncology, Tufts University School of Medicine, New England Medical Center, Boston, MA (USA))

    1990-09-01

    One of the methods currently being used to treat choroidal melanoma employs an episcleral plaque containing I-125 radioactive seeds. However, comprehensive dosimetry studies on the plaque are scarce and controversial. For this work, we use film to study the dosimetry outside the lip of the gold shield of the eye plaque. This lip around the gold shield was made to protect the critical structures behind and adjacent to the lesion. Since the changes of energy spectrum of I-125 in tissue are negligible, film dosimetry seems to be a logical choice because of high spatial resolution required around the lip of the gold plaque. For this study, we first established an H and D curve with dose expressed in a unit of specific dose rate constant. This avoids absolute dose measurements. All film density measurements are made with a 1-mm aperture scan, normalized to the density at the prescription point for tumor of 3--5-mm apical height, i.e., 5 mm from the interior surface of sclera, and converted to percentage isodose curves. With a gold shield, it is found that when the plaque is placed against the optical nerve, the optical disk and macula, located at 2 mm outside the lip, on the exterior surface of sclera, may receive 85% of the prescription dose for a 12-mm plaque and 58% for a 16-mm plaque. For tumors of 8-mm apical height, the optical nerve would receive more than the prescription dose.

  14. Film dosimetry analyses on the effect of gold shielding for Iodine-125 eye plaque therapy for choroidal melanoma

    International Nuclear Information System (INIS)

    Wu, A.; Krasin, F.

    1990-01-01

    One of the methods currently being used to treat choroidal melanoma employs an episcleral plaque containing I-125 radioactive seeds. However, comprehensive dosimetry studies on the plaque are scarce and controversial. For this work, we use film to study the dosimetry outside the lip of the gold shield of the eye plaque. This lip around the gold shield was made to protect the critical structures behind and adjacent to the lesion. Since the changes of energy spectrum of I-125 in tissue are negligible, film dosimetry seems to be a logical choice because of high spatial resolution required around the lip of the gold plaque. For this study, we first established an H and D curve with dose expressed in a unit of specific dose rate constant. This avoids absolute dose measurements. All film density measurements are made with a 1-mm aperture scan, normalized to the density at the prescription point for tumor of 3--5-mm apical height, i.e., 5 mm from the interior surface of sclera, and converted to percentage isodose curves. With a gold shield, it is found that when the plaque is placed against the optical nerve, the optical disk and macula, located at 2 mm outside the lip, on the exterior surface of sclera, may receive 85% of the prescription dose for a 12-mm plaque and 58% for a 16-mm plaque. For tumors of 8-mm apical height, the optical nerve would receive more than the prescription dose

  15. Long-term Results of the UCSF-LBNL Randomized Trial: Charged Particle With Helium Ion Versus Iodine-125 Plaque Therapy for Choroidal and Ciliary Body Melanoma.

    Science.gov (United States)

    Mishra, Kavita K; Quivey, Jeanne M; Daftari, Inder K; Weinberg, Vivian; Cole, Tia B; Patel, Kishan; Castro, Joseph R; Phillips, Theodore L; Char, Devron H

    2015-06-01

    Relevant clinical data are needed given the increasing national interest in charged particle radiation therapy (CPT) programs. Here we report long-term outcomes from the only randomized, stratified trial comparing CPT with iodine-125 plaque therapy for choroidal and ciliary body melanoma. From 1985 to 1991, 184 patients met eligibility criteria and were randomized to receive particle (86 patients) or plaque therapy (98 patients). Patients were stratified by tumor diameter, thickness, distance to disc/fovea, anterior extension, and visual acuity. Tumors close to the optic disc were included. Local tumor control, as well as eye preservation, metastases due to melanoma, and survival were evaluated. Median follow-up times for particle and plaque arm patients were 14.6 years and 12.3 years, respectively (P=.22), and for those alive at last follow-up, 18.5 and 16.5 years, respectively (P=.81). Local control (LC) for particle versus plaque treatment was 100% versus 84% at 5 years, and 98% versus 79% at 12 years, respectively (log rank: P=.0006). If patients with tumors close to the disc (eye preservation (P=.01). CPT was a significant predictor of prolonged disease-free survival (log rank: P=.001). Particle therapy resulted in significantly improved local control, eye preservation, and disease-free survival as confirmed by long-term outcomes from the only randomized study available to date comparing radiation modalities in choroidal and ciliary body melanoma. Copyright © 2015 Elsevier Inc. All rights reserved.

  16. Prescribing to tumor apex in episcleral plaque iodine-125 brachytherapy for medium-sized choroidal melanoma: A single-institutional retrospective review.

    Science.gov (United States)

    Vonk, David Thomas; Kim, Yongbok; Javid, Cameron; Gordon, John D; Stea, Baldassarre

    2015-01-01

    To report an institutional experience with episcleral plaque brachytherapy for medium-sized uveal melanoma. Variations in prescription dose point and dose rate were compared with Collaborative Ocular Melanoma Study (COMS) Group. A retrospective review was performed for 116 patients treated with iodine-125 plaque brachytherapy. About 85 Gy was prescribed to either the tumor apex (108 patients) or at 5 mm (8 patients) with dose rate ranging from 50.6 to 98.2 cGy/h. Patients were followed up for local tumor control, eye preservation, and vision retention. Dose and dose rate to tumor and sensitive structures were calculated. Multivariate and univariate analyses were performed to investigate correlation between clinical outcomes and dose/dose rate variables. Patients in this study were slightly older with worse visual acuity at baseline, but tumor size and position and ratio of ciliary body involvement were comparable to COMS population. Outcomes data were comparable to COMS: 95.3% local tumor control at 5 years and 77.7% vision preservation at 3 years. Only 4 patients needed enucleation because of tumor growth. Significant correlation was found between enucleation and tumor height and maximal scleral dose/dose rate as well as vision retention and tumor height and macula dose/dose rate. For tumors with <5 mm height, prescribing to tumor apex enabled to decrease dose to all sensitive structures without any loss of local control. Although dose rate was lowered to 50.6 cGy/h from the American Brachytherapy Society guidelines (60-105 cGy/h) because of limited availability of operating room (i.e., weekly), there was no difference in either local tumor control or complications. Copyright © 2015 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  17. The Importance of Prostate-specific Antigen (PSA) Nadir and Early Identification of PSA Relapse after 10 Years of Prostate Iodine 125 Seed Brachytherapy in Edinburgh.

    Science.gov (United States)

    McLaren, D B; Kerr, G; Law, A B; Brush, J P; Keanie, J; Malik, J; Keough, W; Ronaldson, T; Lee, J; Kehoe, T

    2015-09-01

    To analyse our 5 and 10 year prostate brachytherapy outcome data and to assess the impact of PSA nadir on relapse free survival and whether an alternative definition of PSA relapse could detect men destined to fail by the Phoenix definition at an earlier time point. 474 men were treated over a 10 year period between 20012 and 2011 and divided into 2 five year cohorts for the purpose of the analysis. The risk of relapse is strongly predicted by post treat prostate-specific antigen (PSA) nadir. After 3 years post-treatment, PSA nadir plus 0.4 ng/ml identified men at risk of relapse 17 months earlier than the Phoenix definition. The Phoenix definition of nadir plus 2.0 ng/ml does not allow the early identification of men destined to relapse. The initiation of salavage therapy at the earliest opportunity could potentially affect subsequent survival and an outline randomised controlled trial proposal is presented. Copyright © 2015 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.

  18. Clinical outcome of intermediate risk prostate cancer treated with iodine 125 mono-therapy: The Hotel-Dieu of Quebec experience

    International Nuclear Information System (INIS)

    Zebentout, O.; Apardian, R.; Beaulieu, L.; Harel, F.; Martin, A.G.; Vigneault, E.; Beaulieu, L.; Harel, F.; Beaulieu, L.

    2010-01-01

    Purpose To describe the biochemical failure-free survival (B.F.F.S.), G.U. toxicity and erectile dysfunction in intermediate risk prostate cancer treated with iodine 125 mono-therapy ( 125 I). Patients and methods Between October 1994 and October 2007, 1282 patients were treated with 125 I at the Hotel Dieu de Quebec. Two hundred patients were intermediate risk prostate cancer. One hundred and fifty-seven had enough follow-up to be evaluated in this study. Biochemical failure-free survival is reported using Phoenix definition. Acute and late G.U. toxicity was described using the International Prostate Symptoms Score (I.P.S.S.) as well as with the rate of bladder catheter. Erectile dysfunction was also reported. Results The mean age of the patients was 65.6 years (S.D. = 6 years) and the mean pretreatment P.S.A. was 8.7 ng/ml. About half of the patients (51%) were T2b/T2c. About 44.6% had a P.S.A. greater than 10 and 4.5% had Gleason score of 7/10. More than half of the patients received a short course of hormones of less than 6 months for cyto-reduction (57.4%). The median follow-up was 60 months. Biochemical failure-free survival at 60-month and 96-month were 87.1% and 81% according to Phoenix definition. The mean I.P.S.S. rose from 5 immediately after the implant to 15 1 month after and then slowly decreased to 8 at 24 months. Acute urinary retention with bladder catheter occurred in 10.9% of patients. Only 4.3% presented erectile dysfunction at 5 months post-implant. Conclusion 125 I mono-therapy for intermediate risk prostate implant gives biochemical failure-free survivals at 5 years and 8 years comparable to those obtained with high dose external beam radiotherapy. G.U. toxicity and erectile dysfunction were low and acceptable. Therefore, the use of 125 I alone in this group of patients could be presented and discussed with the patient in the waiting of phase III validation. (authors)

  19. Long-term Results of the UCSF-LBNL Randomized Trial: Charged Particle With Helium Ion Versus Iodine-125 Plaque Therapy for Choroidal and Ciliary Body Melanoma

    Energy Technology Data Exchange (ETDEWEB)

    Mishra, Kavita K., E-mail: Kavita.mishra@ucsf.edu [Department of Radiation Oncology, University of California-San Francisco, San Francisco, California (United States); Quivey, Jeanne M.; Daftari, Inder K. [Department of Radiation Oncology, University of California-San Francisco, San Francisco, California (United States); Lawrence Berkeley National Laboratory, Berkeley, California (United States); Weinberg, Vivian [Department of Radiation Oncology, University of California-San Francisco, San Francisco, California (United States); Cole, Tia B. [The Tumori Foundation, San Francisco, California (United States); Patel, Kishan [Department of Radiation Oncology, University of California-San Francisco, San Francisco, California (United States); Castro, Joseph R.; Phillips, Theodore L. [Department of Radiation Oncology, University of California-San Francisco, San Francisco, California (United States); Lawrence Berkeley National Laboratory, Berkeley, California (United States); Char, Devron H. [The Tumori Foundation, San Francisco, California (United States); Department of Ophthalmology, University of California-San Francisco, San Francisco, California (United States); Department of Ophthalmology, Stanford University, Palo Alto, California (United States)

    2015-06-01

    Purpose: Relevant clinical data are needed given the increasing national interest in charged particle radiation therapy (CPT) programs. Here we report long-term outcomes from the only randomized, stratified trial comparing CPT with iodine-125 plaque therapy for choroidal and ciliary body melanoma. Methods and Materials: From 1985 to 1991, 184 patients met eligibility criteria and were randomized to receive particle (86 patients) or plaque therapy (98 patients). Patients were stratified by tumor diameter, thickness, distance to disc/fovea, anterior extension, and visual acuity. Tumors close to the optic disc were included. Local tumor control, as well as eye preservation, metastases due to melanoma, and survival were evaluated. Results: Median follow-up times for particle and plaque arm patients were 14.6 years and 12.3 years, respectively (P=.22), and for those alive at last follow-up, 18.5 and 16.5 years, respectively (P=.81). Local control (LC) for particle versus plaque treatment was 100% versus 84% at 5 years, and 98% versus 79% at 12 years, respectively (log rank: P=.0006). If patients with tumors close to the disc (<2 mm) were excluded, CPT still resulted in significantly improved LC: 100% versus 90% at 5 years and 98% versus 86% at 12 years, respectively (log rank: P=.048). Enucleation rate was lower after CPT: 11% versus 22% at 5 years and 17% versus 37% at 12 years, respectively (log rank: P=.01). Using Cox regression model, likelihood ratio test, treatment was the most important predictor of LC (P=.0002) and eye preservation (P=.01). CPT was a significant predictor of prolonged disease-free survival (log rank: P=.001). Conclusions: Particle therapy resulted in significantly improved local control, eye preservation, and disease-free survival as confirmed by long-term outcomes from the only randomized study available to date comparing radiation modalities in choroidal and ciliary body melanoma.

  20. Study of dose deposition for different configurations of OncoSeed 6711 seeds; Estudo da deposicao de dose para diferentes configuracoes de sementes OncoSeed 6711

    Energy Technology Data Exchange (ETDEWEB)

    Tomaz, Lucas Crusoe

    2013-07-01

    Prostate cancer is the second most common cancer among men. Iodine-125 brachytherapy seeds are presented as a form of treatment. In prostate cancer therapy 80-120 iodine-125 seeds are implanted in the organ following a previous planning. During positioning and after it, the implanted seeds can undergo slight displacements relative to the original position. These deviations may cause changes in dose distribution in the tumor volume. This work has made a dosimetry study for iodine-125 seeds used in low dose rate brachytherapy. In the first stage, we performed a one seed dosimetric parameters study following the TG-43 protocol recommendations with the objective of validating our methodology. Then a quantitative study of the variation in dose distribution for three configurations of four seeds OncoSeed 6711 was conducted with two configurations using the seeds in symmetrical positions and the other presenting small displacements. A soft tissue phantom and TLD dosimeters were used. Then a qualitative study of isodose curves of the configurations was performed using radiochromic film, Gafchromic model. This method was used to complement the study of the crystals. The seed´s dosimetric parameters obtained in this work showed excellent agreement with the TG-43 consensual values, thus validating the methodology used in this work. The results obtained with radiochromic film and thermoluminescent dosimeters have shown that there is a significant difference in dose distribution when there is a change in the positioning of the seeds. The use of these two methods simultaneously is efficient since the crystals bring a point view and the film has a global view of the dose distribution. (author)

  1. Seals and sealing handbook

    CERN Document Server

    Flitney, Robert K

    2014-01-01

    Seals and Sealing Handbook, 6th Edition provides comprehensive coverage of sealing technology, bringing together information on all aspects of this area to enable you to make the right sealing choice. This includes detailed coverage on the seals applicable to static, rotary and reciprocating applications, the best materials to use in your sealing systems, and the legislature and regulations that may impact your sealing choices. Updated in line with current trends this updated reference provides the theory necessary for you to select the most appropriate seals for the job and with its 'Failur

  2. Study of dose deposition for different configurations of seeds OncoSeed 6711

    International Nuclear Information System (INIS)

    Tomaz, Lucas Crusoe

    2013-01-01

    Prostate cancer is the second most common cancer among men. lodine-125 brachytherapy seeds are presented as a form of treatment. In prostate cancer therapy 80-120 iodine-125 seeds are implanted in the organ following a previous planning. During positioning and after it, the implanted seeds can undergo slight displacements relative to the original position. These deviations may cause changes in dose distribution in the tumor volume. This work has made a dosimetry study for iodine-125 seeds used in low dose rate brachytherapy. In the first stage, we performed a one seed dosimetric parameters study following the TG-43 protocol recommendations with the objective of validating our methodology. Then a quantitative study of the variation in dose distribution for three configurations of four seeds OncoSeed 6711 was conducted with two configurations using the seeds in symmetrical positions and the other presenting small displacements. A soft tissue phantom and TLD dosimeters were used. Then a qualitative study of isodose curves of the configurations was performed using radiochromic film, Gafchromic model. This method was used to complement the study of the crystals. The seed's dosimetric parameters obtained in this work showed excellent agreement with the TG-43 consensual values, thus validating the methodology used in this work. The results obtained with radiochromic film and thermoluminescent dosimeters have shown that there is a significant difference in dose distribution when there is a change in the positioning of the seeds. The use of these two methods simultaneously is efficient since the crystals bring a point view and the film has a global view of the dose distribution. (author)

  3. Seals and sealing handbook

    CERN Document Server

    Flitney, Robert K

    2007-01-01

    Wherever machinery operates there will be seals of some kind ensuring that the machine remains lubricated, the fluid being pumped does not leak, or the gas does not enter the atmosphere. Seals are ubiquitous, in industry, the home, transport and many other places. This 5th edition of a long-established title covers all types of seal by application: static, rotary, reciprocating etc. The book bears little resemblance to its predecessors, and Robert Flitney has re-planned and re-written every aspect of the subject. No engineer, designer or manufacturer of seals can afford to be without this uniq

  4. Use of brachytherapy with permanent implants of iodine-125 in localized prostate cancer; La curietherapie par implants permanents d'I-125 dans le cancer localise de la prostate

    Energy Technology Data Exchange (ETDEWEB)

    Bladou, F.; Serment, G. [Hopital Salvador, Service d' Urologie, 13 - Marseille (France); Salem, N.; Simonian, M. [Hopital Salvador, Dept. de Radiotherapie, 13 - Marseille (France); Rosello, R.; Ternier, F. [Institut Paoli-Calmettes, Dept. de Radiologie, 13 - Marseille (France)

    2002-07-01

    Approximately 15,000 cases of early stage prostate cancer T1 and T2 are diagnosed every year in France by testing for PSA and performing prostatic biopsies. The treatment of these localized forms is based in most cases on radical prostatectomy or nn external beam radiotherapy. Although the ontological results obtained by these two therapeutic methods are satisfactory and equivalent in the long term, the side effects can be important. For a number of years, trans-perineal brachytherapy using permanent implants of iodine -125 or palladium-103 has proved itself as an alternative therapy with equivalent medium to long-term results. The low urinary, digestive and sexual side effects of prostate brachytherapy are important reasons for the enthusiasm among patients and the medical community for this therapy and the growing number of applications and centres which practice it. In September 1998 we started the prostate brachytherapy programmes- in Marseilles with close collaboration between the department of urology of the Hopital Salvator, and the departments of radiotherapy, medical imaging and medical physics of the Institut Paoli-Calmettes. To date, around 250 patients with localized adenocarcinoma of the prostate have benefited from this alternative therapy in our centre. Preliminary results, with a 3 year-follow-up, are comparable to results published in the literature by pioneer teams. (authors)

  5. Study of dose deposition for different configurations of seeds OncoSeed 6711; Estudo da deposicao de dose para diferentes configuracoes de sementes OncoSeed 6711

    Energy Technology Data Exchange (ETDEWEB)

    Tomaz, Lucas Crusoe

    2013-08-01

    Prostate cancer is the second most common cancer among men. lodine-125 brachytherapy seeds are presented as a form of treatment. In prostate cancer therapy 80-120 iodine-125 seeds are implanted in the organ following a previous planning. During positioning and after it, the implanted seeds can undergo slight displacements relative to the original position. These deviations may cause changes in dose distribution in the tumor volume. This work has made a dosimetry study for iodine-125 seeds used in low dose rate brachytherapy. In the first stage, we performed a one seed dosimetric parameters study following the TG-43 protocol recommendations with the objective of validating our methodology. Then a quantitative study of the variation in dose distribution for three configurations of four seeds OncoSeed 6711 was conducted with two configurations using the seeds in symmetrical positions and the other presenting small displacements. A soft tissue phantom and TLD dosimeters were used. Then a qualitative study of isodose curves of the configurations was performed using radiochromic film, Gafchromic model. This method was used to complement the study of the crystals. The seed's dosimetric parameters obtained in this work showed excellent agreement with the TG-43 consensual values, thus validating the methodology used in this work. The results obtained with radiochromic film and thermoluminescent dosimeters have shown that there is a significant difference in dose distribution when there is a change in the positioning of the seeds. The use of these two methods simultaneously is efficient since the crystals bring a point view and the film has a global view of the dose distribution. (author)

  6. seeds

    African Journals Online (AJOL)

    Owner

    peptidohydrolase (8.0%) from mung bean seedlings. (Baumgartner and Chrispeels, 1977), EP-HG (4.5%) from horse gram seedlings ( Rajeswari, 1997), acidic protease (15%) from germinating winged-bean seeds. (Usha and Singh, 1996) and EP-1 (1.6%) from barley seedlings and GA3-induced cysteine protease (3.38%).

  7. Glass sealing

    Energy Technology Data Exchange (ETDEWEB)

    Brow, R.K.; Kovacic, L.; Chambers, R.S. [Sandia National Labs., Albuquerque, NM (United States)

    1996-04-01

    Hernetic glass sealing technologies developed for weapons component applications can be utilized for the design and manufacture of fuel cells. Design and processing of of a seal are optimized through an integrated approach based on glass composition research, finite element analysis, and sealing process definition. Glass sealing procedures are selected to accommodate the limits imposed by glass composition and predicted calculations.

  8. Mechanical seals

    CERN Document Server

    Mayer, E

    1977-01-01

    Mechanical Seals, Third Edition is a source of practical information on the design and use of mechanical seals. Topics range from design fundamentals and test rigs to leakage, wear, friction and power, reliability, and special designs. This text is comprised of nine chapters; the first of which gives a general overview of seals, including various types of seals and their applications. Attention then turns to the fundamentals of seal design, with emphasis on six requirements that must be considered: sealing effectiveness, length of life, reliability, power consumption, space requirements, and c

  9. Security seal

    Science.gov (United States)

    Gobeli, Garth W.

    1985-01-01

    Security for a package or verifying seal in plastic material is provided by a print seal with unique thermally produced imprints in the plastic. If tampering is attempted, the material is irreparably damaged and thus detectable. The pattern of the imprints, similar to "fingerprints" are recorded as a positive identification for the seal, and corresponding recordings made to allow comparison. The integrity of the seal is proved by the comparison of imprint identification records made by laser beam projection.

  10. Use of iodine-125 brachytherapy in treatment of choroidal melanomas, technic and preliminary analysis of 78 patients; Traitement conservateur des melanomes choroidiens par curietherapie par l'iode 125, technique et analyse preliminaire d'une serie de 78 patients

    Energy Technology Data Exchange (ETDEWEB)

    Quetin, P.; Schumacher, C.; Schraub, S. [Centre Paul-Strauss, Dept. de Radiotherapie, 67 - Strasbourg (France); Meyer, L.; Polto, F.; Sahel, J. [Hopitaux Universitaires de Strasbourg, Clinique Ophtalmologique, 67 (France); Magnenet, P. [Centre Paul-Strauss, Dept. de Radiophysique, 67 - Strasbourg (France); Andres, E. [Hopital de Hautepierre, Medecine Interne, 67 - Strasbourg (France)

    2001-12-01

    Purpose. - Iodine 125 curietherapy is one of the conservative treatments of uveal melanoma. The technique used to achieve these results was simplified through the physical characteristics of the radioelement and the optimized-dosimetry program employed. Patients and methods. - 78 patients with choroidal melanoma were treated with iodine 125. About 100 Gy were delivered to the superior pole of the tumour. The minimal length of follow-up was 17 months and the average, 67 months. Results. -There was 88% local control, leading to lowered visual acuity in 76 % of the cases. Radiation retinopathy, directly related to proximity to the macula, is the principle etiology. Seven patients died of hepatic metastasis, five patients were enucleated. Four patients were further treated with proton-therapy to make up for non-control locally. Conclusion. -One dose of 100 Gy to the superior pole of the tumor seemed to lead to good local control, with the exception of complications related to proximity to the macula and the optic nerve. In this attempt to optimize irradiation, the time lapse between any benefit in local control derived from irradiation and post-therapeutic complications observed remains insufficient to evaluate any relationship. (authors)

  11. Nozzle seal

    International Nuclear Information System (INIS)

    Groff, R.D.; Vatovec, R.J.

    1978-01-01

    In an illustrative embodiment of the invention, a nuclear reactor pressure vessel, having an internal hoop from which the heated coolant emerges from the reactor core and passes through to the reactor outlet nozzles, is provided with annular sealing members operatively disposed between the outlet nozzle and the hoop and partly within a retaining annulus formed in the hoop. The sealing members are biased against the pressure vessel and the hoop and one of the sealing members is provided with a piston type pressure ring sealing member which effectively closes the path between the inlet and outlet coolants in the region about the outlet nozzle establishing a leak-proof condition. Furthermore, the flexible responsiveness of the seal assures that the seal will not structurally couple the hoop to the pressure vessel

  12. Ferrules seals

    Science.gov (United States)

    Smith, J.L.

    1984-07-10

    A device is provided for sealing an inner tube and an outer tube without excessively deforming the tubes. The device includes two ferrules which cooperate to form a vacuum-tight seal between the inner tube and outer tube and having mating surfaces such that overtightening is not possible. 3 figs.

  13. Ceramic Seal.

    Energy Technology Data Exchange (ETDEWEB)

    Smartt, Heidi A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Romero, Juan A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Custer, Joyce Olsen [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Hymel, Ross W. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Krementz, Dan [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Gobin, Derek [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Harpring, Larry [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Martinez-Rodriguez, Michael [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Varble, Don [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); DiMaio, Jeff [Tetramer Technologies, Pendleton, SC (United States); Hudson, Stephen [Tetramer Technologies, Pendleton, SC (United States)

    2016-11-01

    Containment/Surveillance (C/S) measures are critical to any verification regime in order to maintain Continuity of Knowledge (CoK). The Ceramic Seal project is research into the next generation technologies to advance C/S, in particular improving security and efficiency. The Ceramic Seal is a small form factor loop seal with improved tamper-indication including a frangible seal body, tamper planes, external coatings, and electronic monitoring of the seal body integrity. It improves efficiency through a self-securing wire and in-situ verification with a handheld reader. Sandia National Laboratories (SNL) and Savannah River National Laboratory (SRNL), under sponsorship from the U.S. National Nuclear Security Administration (NNSA) Office of Defense Nuclear Nonproliferation Research and Development (DNN R&D), have previously designed and have now fabricated and tested Ceramic Seals. Tests have occurred at both SNL and SRNL, with different types of tests occurring at each facility. This interim report will describe the Ceramic Seal prototype, the design and development of a handheld standalone reader and an interface to a data acquisition system, fabrication of the seals, and results of initial testing.

  14. Ferrules seals

    Science.gov (United States)

    Smith, James L.

    1984-01-01

    A device is provided for sealing an inner tube and an outer tube without excessively deforming the tubes. The device includes two ferrules which cooperate to form a vacuum-tight seal between the inner tube and outer tube and having mating surfaces such that overtightening is not possible.

  15. Sealing devices

    International Nuclear Information System (INIS)

    Coulson, R.A.

    1980-01-01

    A sealing device for minimising the leakage of toxic or radioactive contaminated environments through a biological shield along an opening through which a flexible component moves that penetrates the shield. The sealing device comprises an outer tubular member which extends over a length not less than the maximum longitudinal movement of the component along the opening. An inner sealing block is located intermediate the length of the component by connectors and is positioned in the bore of the outer tubular member to slide in the bore and effect a seal over the entire longitudinal movement of the component. The cross-section of the device may be circular and the block may be of polytetrafluoroethylene or of nylon impregnated with molybdenum or may be metallic. A number of the sealing devices may be combined into an assembly for a plurality of adjacent longitudinally movable components, each adapted to sustain a tensile load, providing the various drives of a master-slave manipulator. (author)

  16. Seal Counts

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Database of seal counts from aerial photography. Counts by image, site, species, and date are stored in the database along with information on entanglements and...

  17. [Christmas seals].

    Science.gov (United States)

    Loytved, G

    2006-11-01

    Christmas seals, i. e., special stamps used to decorate or seal Christmas and New Year's mail, were created by the Danish post office clerk E. Holboell. The proceeds from the sale of the stickers were meant to alleviate the suffering of children sick with tuberculosis. The first Christmas seal, showing a portrait of Queen Louise of Denmark, was issued on December 10, 1904. The demand at the post office was enormous. The funds raised exceeded all expectations and made it possible to finance the construction of a sanatorium for tuberculosis children. The idea of Christmas seals spread quickly around the world and ended up being copied in 130 countries. At the beginning of the 20 (th) century, the small stamp with the red double-barred cross became a banner for the crusade against tuberculosis. For many patients, it also represented a symbol of hope for recovery even though this hope, given the cure rates of a sanatorium treatment, only became a reality for a few. Worldwide, Christmas seals were and are colourful and imaginatively designed, mostly with Christmas symbols or motives relating to the fight against tuberculosis. The funds raised through the sale of the seals initially helped to build hospitals and were later also used to screen persons at risk for tuberculosis, to improve housing conditions of patients and for other measures of support. With the decrease of tuberculosis, some organisations discontinued fundraising through Christmas seals while others widened their intended purpose and supported, for example, the prevention of and research on lung diseases. In Germany, Christmas seals are closely connected with the German Central Committee against Tuberculosis. Today the "Kuratorium Tuberkulose in der Welt" is the only organisation in this country that still raises funds by this means. The funds are mostly used to assist developing countries with a high burden of tuberculosis.

  18. Disease-related effects of perioperative blood transfusions associated with 125I seed implantation for prostate carcinoma

    International Nuclear Information System (INIS)

    Petersen, J.P.; Schellhammer, P.F.; el-Mahdi, A.M.

    1990-01-01

    In some retrospective studies perioperative transfusions during oncologic surgery have been shown to decrease the time interval between surgery and local and/or distant recurrence of cancer. This study examines the disease-related effect, if any, of perioperative blood transfusions among 108 patients with localized carcinoma of the prostate treated by radioactive iodine-125 seed implantation of the prostate and lymphadenectomy. When all subjects were analyzed, there was no statistical difference of local and distant failure between the transfused and nontransfused groups. Patients with well-differentiated tumors had statistically fewer local recurrences (0% vs 22%, p = 0.036) if they were transfused perioperatively. However, the difference in distant metastases (0% vs 11%) was not statistically significant (p = 0.21). In contrast, patients with moderately and poorly differentiated disease receiving transfusions had more local recurrences and metastases, though this was not statistically significant. Our data suggest that there is no obvious evidence that perioperative blood transfusions have an adverse effect on local recurrence or distant metastases for iodine-125 seed implantation of carcinoma of the prostate

  19. Refining prostate seed brachytherapy: Comparing high-, intermediate-, and low-activity seeds for I-125 permanent seed prostate brachytherapy.

    Science.gov (United States)

    Delouya, Guila; Bahary, Pascal; Carrier, Jean-François; Larouche, Renée-Xavière; Hervieux, Yannick; Béliveau-Nadeau, Dominic; Donath, David; Taussky, Daniel

    2015-01-01

    To analyze the difference in prostate coverage and dose to the rectum in men with prostate carcinoma treated with permanent seed brachytherapy with different seed activities. Forty-nine patients treated with iodine-125 permanent seed prostate brachytherapy with low-activity seeds of 0.30-0.37 mCi were identified. For each of these patients, 2 patients with similar prostate volume (±2 cc) were paired: one treated with intermediate seed activity (0.44-0.46 mCi) and one with high seed activity (0.60-0.66 mCi). The doses to prostate and rectum were compared using CT on Day 30. A total of 147 patients divided into the three seed activity groups were analyzed. Mean prostate volume was 35.7 cc (standard deviation [SD], 11.70). Compared with low-activity seeds, implants with high-activity seeds consisted of an average of 22 seeds and 4.7 needles less. The dose to the prostate (prostate volume receiving 100% of the prescribed dose [V100], prostate volume receiving 150% of the prescribed dose, and minimal dose covering 90% of the prostate volume expressed in Gy) was not higher on Day 30 (p = 0.58-0.97). The mean volume (in cubic centimeters) of rectal wall receiving 100% of the prescribed dose (V100) increased with activity: low activity, 0.34 cc (SD, 0.49), intermediate activity, 0.47 cc (SD, 0.48), and high activity, 0.72 cc (SD, 0.79) (p = 0.009). There was a trend (p = 0.073) toward a higher frequency of clinically unfavorable rectal dosimetry (V100 > 1.3 cc) in patients with high-activity seeds (16.7%) compared with low-activity (6.3%) or intermediate-activity (4.2%) seeds. High-activity seeds do not result in a higher dose to the prostate but in a higher dose to the rectum. Copyright © 2015 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  20. Relationship between two year PSA nadir and biochemical recurrence in prostate cancer patients treated with iodine-125 brachytherapy; A relacao entre PSA nadir de dois anos e recidiva bioquimica no tratamento do cancer de prostata com braquiterapia de semente de iodo-125

    Energy Technology Data Exchange (ETDEWEB)

    Franca, Carlos Antonio da Silva; Vieira, Sergio Lannes; Penna, Antonio Belmiro Rodrigues Campbell, E-mail: carlosfranca@cremerj.org.br [Instituto Brasileiro de Oncologia (IBO), Rio de Janeiro, RJ (Brazil); Radioterapia Botafogo, Rio de janeiro, RJ (Brazil); Carvalho, Antonio Carlos Pires [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil); Bernabe, Antonio Jose Serrano [Radioterapia Botafogo, Rio de janeiro, RJ (Brazil)

    2014-03-15

    Objective: to evaluate the relationship between two year PSA nadir (PSAn) after brachytherapy and biochemical recurrence rates in prostate cancer patients. Materials and methods: In the period from January 1998 to August 2007, 120 patients were treated with iodine-125 brachytherapy alone. The results analysis was based on the definition of biochemical recurrence according to the Phoenix Consensus. Results: biochemical control was observed in 86 patients (71.7%), and biochemical recurrence, in 34 (28.3%). Mean PSAn was 0.53 ng/ml. The mean follow-up was 98 months. The patients were divided into two groups: group 1, with two year PSAn < 0.5 ng/ml after brachytherapy (74 patients; 61.7%), and group 2, with two year PSAn ≥ 0.5 ng/ml after brachytherapy (46 patients; 38.3%). Group 1 presented biochemical recurrence in 15 patients (20.3%), and group 2, in 19 patients (43.2%) (p < 0.02). The analysis of biochemical disease-free survival at seven years, stratified by the two groups, showed values of 80% and 64% (p < 0.02), respectively. Conclusion: levels of two year PSAn ≥ 0.5 ng/ml after brachytherapy are strongly correlated with a poor prognosis. This fact may help to identify patients at risk for disease recurrence. (author)

  1. Iodine 125 prostate brachytherapy: prognostic factors for long-term urinary, digestive and sexual toxicities;Curietherapie de prostate par iode 125: facteurs pronostiques de longue duree de toxicite urinaire, digestive et sexuelle

    Energy Technology Data Exchange (ETDEWEB)

    Doyen, J.; Mohammed Ali, A.; Ginot, A.; Ferre, M.; Castelli, J.; Hannoun-Levi, J.M. [Centre Antoine-Lacassagne, Dept. de Radiotherapie Oncologique, 06 - Nice (France); Chamorey, E. [Centre Antoine-Lacassagne, Unite de Statistiques Medicales, 06 - Nice (France); Mohammed Ali, A. [Faculte de Medecine, SOHAG (Egypt); Quintens, H.; Amiel, J. [CHU Pasteur, Service d' Urologie, 06 - Nice (France)

    2009-12-15

    .4 %) presented a sexual toxicity; 26.9 % (49 patients) and 5 % (nine patients) were scored as grade 2 and 3 respectively. A number of seeds greater than 75 (p = 0.032) and S grade greater than or equal to 2 (p < 0.0001) were recognized as prognostic factors in U.V.A.. S grade was the only prognostic factor in M.V.A. (p 0.0015). Conclusion The duration of U, D and S toxicity is strongly correlated with a high number of toxicities and the grade of toxicity. This analysis allows for better information given to the patient regarding the duration of the post-treatment complications

  2. Mechanical Seal Assembly

    Energy Technology Data Exchange (ETDEWEB)

    Kotlyar, Oleg M.

    1999-06-18

    An improved mechanical seal assembly is provided for sealing rotating shafts with respect to their shaft housings, wherein the rotating shafts are subject to substantial axial vibrations. The mechanical seal assembly generally includes a rotating sealing ring fixed to the shaft, a non-rotating sealing ring adjacent to and in close contact with the rotating sealing ring for forming an annular seal about the shaft, and a mechanical diode element that applies a biasing force to the non-rotating sealing ring by means of hemispherical joint. The alignment of the mechanical diode with respect to the sealing rings is maintained by a series of linear bearings positioned axially along a desired length of the mechanical diode. Alternative embodiments include mechanical or hydraulic amplification components for amplifying axial displacement of the non-rotating sealing ring and transferring it to the mechanical diode.

  3. Mechanical seal assembly

    Science.gov (United States)

    Kotlyar, Oleg M.

    2001-01-01

    An improved mechanical seal assembly is provided for sealing rotating shafts with respect to their shaft housings, wherein the rotating shafts are subject to substantial axial vibrations. The mechanical seal assembly generally includes a rotating sealing ring fixed to the shaft, a non-rotating sealing ring adjacent to and in close contact with the rotating sealing ring for forming an annular seal about the shaft, and a mechanical diode element that applies a biasing force to the non-rotating sealing ring by means of hemispherical joint. The alignment of the mechanical diode with respect to the sealing rings is maintained by a series of linear bearings positioned axially along a desired length of the mechanical diode. Alternative embodiments include mechanical or hydraulic amplification components for amplifying axial displacement of the non-rotating sealing ring and transferring it to the mechanical diode.

  4. Seal design alternatives study

    International Nuclear Information System (INIS)

    Van Sambeek, L.L.; Luo, D.D.; Lin, M.S.; Ostrowski, W.; Oyenuga, D.

    1993-06-01

    This report presents the results from a study of various sealing alternatives for the WIPP sealing system. Overall, the sealing system has the purpose of reducing to the extent possible the potential for fluids (either gas or liquid) from entering or leaving the repository. The sealing system is divided into three subsystems: drift and panel seals within the repository horizon, shaft seals in each of the four shafts, and borehole seals. Alternatives to the baseline configuration for the WIPP seal system design included evaluating different geometries and schedules for seal component installations and the use of different materials for seal components. Order-of-magnitude costs for the various alternatives were prepared as part of the study. Firm recommendations are not presented, but the advantages and disadvantages of the alternatives are discussed. Technical information deficiencies are identified and studies are outlined which can provide required information

  5. Iodine-125 metaraminol: A new platelet specific labeling agent

    International Nuclear Information System (INIS)

    Ohmomo, Y.; Yokoyama, A.; Kawaii, K.; Horiuchi, K.; Saji, H.; Torizuka, K.

    1984-01-01

    In the search for a platelet specific labeling agent, Metaraminol (MA), which is a sympatomimetic amine used for the treatment of hypotension, cardiogenic shock and well recognized as a drug actively incorporated and accumulated in platelet, attracted the authors' attention. Using the classical chloramine-T iodination method, a high labeling efficiency near 98%, reaching a specific activity up to about 1000 Ci/mmole was obtained. Upon the harvest of platelet, only as platelet rich plasma (PRP), the labeling with this radiopharmaceutical was easily performed by incubation at 37 0 C for 10 min. Labeling efficiency as high as 63.0 +- 3.1% at 24 x 10/sup 8/ cells/ml was obtained. In in-vitro studies, the unaltered state of I-125 MA labeled platelet, with their cellular functions fully retained was demonstrated. Pharmacological study indicated a specific incorporation of I-125 MA by active transport system similar to that of 5-HT, along with passive diffusion. Then the in-vivo study carried out in rabbits with induced thrombi on the femoral artery, showed rather rapid disappearance of the I-125 MA labeled autologous platelet radioactivity, from circulating blood reaching as high thrombus-to-blood activity ratio as 19.8+-4.3 within 30 min post-administration. This new platelet labeling agent, I-125 MA, has many advantages over the use of IN-111 oxine and holds considerable promise for thrombus imaging with single photon emission CT upon the availability of I-123 MA

  6. Iodine-125 brachytherapy for prostate cancer: first published Australian experience

    International Nuclear Information System (INIS)

    Joseph, David J.; Woo, Tony C.S.; Haworth, Annette

    2004-01-01

    With the emergence of new imaging and implant'techniques, prostate brachytherapy has become increasingly popular over the last decade. Brachytherapy promises to deliver twice the biologically effective dose as conventional external beam treatments without increasing the dose to tissues surrounding the prostate. However, there are few or no published Australian series of its efficacy in the clinic. We present the experience of one of the first centres in Australia to offer this service to its patients: a series from Sir Charles Gairdner Hospital in Western Australia. We present data on the efficacy of brachytherapy in maintaining prostate specific antigen levels, as well as the rate of urinary, rectal and sexual complications. Our results compare favourably with other brachytherapy and external beam treatment series. We believe that with the increasing trend towards dose escalation and novel therapies, standardized measurements of success and failure need to be better defined, and that randomized trials comparing modalities are needed to improve the management of prostate cancer Copyright (2004) Blackwell Publishing Asia Pty Ltd

  7. Preparation of iodine-125-labeled iothalamate for renal clearance measurements

    International Nuclear Information System (INIS)

    Rao, S.A.; Herold, T.J.; Dewanjee, M.K.

    1983-01-01

    Iothalamate, a derivative of benzoic acid, is used as a contrast medium for renal function studies, particularly for measurement of glomerular filtration rate. Its chemical composition and clearance properties are similar to those of diatrizoate. The structural differences between these groups of iodinated benzoic acid derivatives are dependent on the groups attached at the 3- and 5-positions of 2,4,6-tri-iodobenzoic acid. The renal clearance of sodium iothalamate in humans closely approximates that of inulin, and it is used as a replacement for inulin in determining glomerular filtration rate. /sup 125/I-labeled iothalamate sodium can be prepared by the exchange-labeling method at pH 4.0. Iothalamate must first be isolated from the contrast medium preparation and purified before radioiodination. After radioiodination, the product is purified by means of precipitation and is then converted to the sodium salt

  8. Review of options for managing iodine-125 wastes

    International Nuclear Information System (INIS)

    Lock, P.J.; Wakerley, M.W.

    1991-01-01

    Data on the nature, radioactive content and management options used for I-125 wastes that are produced in England and Wales and fall within the provisions of the Radioactive Substances Act 1960 have been collated. The options for, and impacts of the disposal of these wastes have been reviewed and discussed. In addition storage for decay has been reviewed. The necessary storage requirements and methods of storage for the various waste forms have been examined. Conclusions are drawn with respect to the potential/suitability of the various waste management options. (author)

  9. Mechanical seal program

    International Nuclear Information System (INIS)

    Lowery, G.B.

    1983-01-01

    The experimental plans and timing for completion of the mechanical seal program for both the slurry and transfer pumps are given. The slurry pump seal program will be completed by April 1984 with turnover of two seals in pumps to SRP Tank 15H. Transfer pump seal design will be released for plant use by May 1984. Also included are various other pump and seal related tests

  10. Nuclear reactor sealing system

    International Nuclear Information System (INIS)

    McEdwards, J.A.

    1983-01-01

    A liquid metal-cooled nuclear reactor sealing system is disclosed. The nuclear reactor includes a vessel sealed at its upper end by a closure head. The closure head comprises at least two components, one of which is rotatable; and the two components define an annulus therebetween. The sealing system includes at least a first and second inflatable seal disposed in series in an upper portion of the annulus. The system further includes a dip seal extending into a body of insulation located adjacent a bottom portion of the closure head. The dip seal comprises a trough formed by a lower portion of one of the components, and a seal blade pendently supported from the other component and extending downwardly into the trough. A body of liquid metal is contained in the trough which submerges a portion of the seal blade. The seal blade is provided with at least one aperture located above the body of liquid metal for providing fluid communication between the annulus intermediate the dip seal and the inflatable seals, and a body of cover gas located inside the vessel. There also is provided means for introducing a purge gas into the annulus intermediate the inflatable seals and the seal blade. The purge gas is introduced in an amount sufficient to substantially reduce diffusion of radioactive cover gas or sodium vapor up to the inflatable seals. The purge gas mixes with the cover gas in the reactor vessel where it can be withdrawn from the vessel for treatment and recycle to the vessel

  11. Magnetically Actuated Seal Project

    Data.gov (United States)

    National Aeronautics and Space Administration — FTT proposes development of a magnetically actuated dynamic seal. Dynamic seals are used throughout the turbopump in high-performance, pump-fed, liquid rocket...

  12. Seal coat research project

    Science.gov (United States)

    1999-12-01

    This study evaluates the use of seal coating as a method to protect bituminous pavements from oxidation, water infiltration, and raveling. The Minnesota Department of Transportation (Mn/DOT) applied seal coating to a roadway segment of Trunk Highway ...

  13. Magnetically Actuated Seal

    Science.gov (United States)

    Pinera, Alex

    2013-01-01

    This invention is a magnetically actuated seal in which either a single electromagnet, or multiple electromagnets, are used to control the seal's position. This system can either be an open/ close type of system or an actively controlled system.

  14. Reactor vessel sealing plug

    International Nuclear Information System (INIS)

    Dooley, R.A.

    1986-01-01

    This invention relates to an apparatus and method for sealing the cold leg nozzles of a nuclear reactor pressure vessel from a remote location during maintenance and inspection of associated steam generators and pumps while the pressure vessel and refueling canal are filled with water. The apparatus includes a sealing plug for mechanically sealing the cold leg nozzle from the inside of a reactor pressure vessel. The sealing plugs include a primary and a secondary O-ring. An installation tool is suspended within the reactor vessel and carries the sealing plug. The tool telescopes to insert the sealing plug within the cold leg nozzle, and to subsequently remove the plug. Hydraulic means are used to activate the sealing plug, and support means serve to suspend the installation tool within the reactor vessel during installation and removal of the sealing plug

  15. Hermetically Sealed Compressor

    Science.gov (United States)

    Holtzapple, Mark T.

    1994-01-01

    Proposed hermetically sealed pump compresses fluid to pressure up to 4,000 atm (400 MPa). Pump employs linear electric motor instead of rotary motor to avoid need for leakage-prone rotary seals. In addition, linear-motor-powered pump would not require packings to seal its piston. Concept thus eliminates major cause of friction and wear. Pump is double-ended diaphragm-type compressor. All moving parts sealed within compressor housing.

  16. Severe service sealing solutions

    International Nuclear Information System (INIS)

    Metcalfe, R.; Wensel, R.

    1994-09-01

    Successful sealing usually requires much more than initial leak-tightness. Friction and wear must also be acceptable, requiring a good understanding of tribology at the sealing interface. This paper describes various sealing solutions for severe service conditions. The CAN2A and CAN8 rotary face seals use tungsten carbide against carbon-graphite to achieve low leakage and long lifetime in nuclear main coolant pumps. The smaller CAN6 seal successfully uses tungsten carbide against silicon carbide in reactor water cleanup pump service. Where friction in CANDU fuelling machine rams must be essentially zero, a hydrostatic seal using two silicon carbide faces is the solution. In the NRU reactor moderator pumps, where pressure is much lower, eccentric seals that prevent boiling at the seal faces are giving excellent service. All these rotary face seals rely on supplementary elastomer seals between their parts. An integrated engineering approach to high performance sealing with O-rings is described. This is epitomized in critical Space Shuttle applications, but is increasingly being applied in CANDU plants. It includes gland design, selection and qualification of material, quality assurance, detection of defects and the effects of lubrication, surface finish, squeeze, stretch and volume constraints. In conclusion, for the severe service applications described, customized solutions have more than paid for themselves by higher reliability, lower maintenance requirements and reduced outage time. (author)

  17. High pressure shaft seal

    International Nuclear Information System (INIS)

    Martinson, A.R.; Rogers, V.D.

    1980-01-01

    In relation to reactor primary coolant pumps, mechanical seal assembly for a pump shaft is disclosed which features a rotating seal ring mounting system which utilizes a rigid support ring loaded through narrow annular projections in combination with centering non-sealing O-rings which effectively isolate the rotating seal ring from temperature and pressure transients while securely positioning the ring to adjacent parts. A stationary seal ring mounting configuration allows the stationary seal ring freedom of motion to follow shaft axial movement up to 3/4 of an inch and shaft tilt about the pump axis without any change in the hydraulic or pressure loading on the stationary seal ring or its carrier. (author)

  18. Flexible ring seal

    International Nuclear Information System (INIS)

    Abbes, Claude; Gournier, Andre; Rouaud, Christian; Villepoix, Raymond de.

    1976-01-01

    The invention concerns a flexible metal ring seal, able to ensure a perfect seal between two bearings due to the crushing and elastic deformation properties akin to similar properties in elastomers. Various designs of seal of this kind are already known, particularly a seal made of a core formed by a helical wire spring with close-wound turns and with high axial compression ratio, closed on itself and having the shape of an annulus. This wire ring is surrounded by at least one envelope having at rest the shape of a toroidal surface of which the generating circle does not close on itself. In a particular design mode, the seal in question can include, around the internal spring, two envelopes of which one in contact with the spring is composed of a low ductility elastic metal, such as mild steel or stainless steel and the other is, on the contrary, made of a malleable metal, such as copper or nickel. The first envelope evenly distributes the partial crushing of the spring, when the seal is tightened, on the second envelope which closely fits the two surfaces between which the seal operates. The stress-crushing curve characteristic of the seal comprises two separate parts, the first with a relatively sharp slope corresponds to the start of the seal compression phase, enabling at least some of these curves to reach the requisite seal threshold very quickly, then, beyond this, a second part, practically flat, where the stress is appreciably constant for a wide operating bracket [fr

  19. Seals in nuclear reactors

    International Nuclear Information System (INIS)

    1979-01-01

    The seals described are for use in a nuclear reactor where there are fuel assemblies in a vessel, an inlet and an outlet for circulating a coolant in heat transfer relationship with the fuel assemblies and a closure head on the vessel in a tight fluid relationship. The closure head comprises rotatable plugs which have mechanical seals disposed in the annulus around each plug while allowing free rotation of the plug when the seal is not actuated. The seal is usually an elastomer or copper. A means of actuating the seal is attached for drawing it vertically into the annulus for sealing. When the reactor coolant is liquid sodium, contact with oxygen must be avoided and argon cover gas fills the space between the bottom of the closure head and the coolant liquid level and the annuli in the closure head. (U.K.)

  20. Seals in nuclear reactors

    International Nuclear Information System (INIS)

    1979-01-01

    The aim of this invention is the provision of improved seals for reactor vessels in which fuel assemblies are located together with inlets and outlets for the circulation of a coolant. The object is to provide a seal arrangement for the rotatable plugs of nuclear reactor closure heads which has good sealing capacities over a wide gap during operation of the reactor but which also permits uninhibited rotation of the plugs for maintenance. (U.K.)

  1. Compliant seal development

    Science.gov (United States)

    Hendricks, Robert C.

    1993-10-01

    The compliant metallic seal combines the noncontact feature of the labyrinth seal, the low leakage of a mechanical seal, and the compliant nature of the brush seal. It consists of several thin metallic elements or leaves mounted within a ring which is press fit into the housing, and in form, sort of resembles a lip seal sections wiping the shaft. A second set of overlapping cover leaves are placed on top of the shaft riding leaves which reduces leakage and provides stiffness. The leaves can be straight or angle cut. The shaft riding fingers are designed with mismatched curvature to provide lift off similar to the Rayleigh lift pads in mechanical seals with leading edge clearances nearly twice those of the trailing edge as as shown by Fleming to be optimal for gas flows in convergent seal passages. Leading edge clearances range from 300 to 500 microinches. Balance pockets beneath the leaves provide fluid film feed to the 'Rayleigh lift' surface and the proper balance ratio (mechanical seal) when combined with the static pressure and film pressure. The leaves flex in the radial direction and accommodate thermomechanical behavior as well as axial motion and angular misalignment. In the static mode, there is a net closing force on the leaves. The seals were tested to 70 psi at speeds to 16,000 rpm or surface speeds to 330 fps and temperatures from ambient to 440 F. A slow cycle through the rig critical at 10,000 rpm induced a radial vibration response of 0.004 to 0.005 inch were accommodated by the seal. Preliminary performance data are encouraging demonstrating hydrodynamic liftoff and noncontacting operation at pressure and speeds typical of gas turbine engines. The leakage performance data are significantly better than commercial labyrinth and brush seals which should be expected as this design incorporates the features of the low leakage face or mechanical seal along with the flexibility of the brush configuration.

  2. Ropes eye plaque brachytherapy dosimetry for two models of 103Pd seeds

    International Nuclear Information System (INIS)

    Saidi, P.; Sadeghi, M.; Shirazi, A.; Tenreiro, C.

    2011-01-01

    Full text: Brachytherapy dose distributions are calculated for I5 m m ROPES eye plaque loaded with model Theragenics200 and IR06-103Pd seeds. The effects of stainless steel backing and Acrylic insert on dose distribution along the central axis of the eye plaque and at critical ocular structure are investigated. Monte Carlo simulation was carried out with the Version 5 of the MCNP. The dose at critical ocular structure by considering the eye composition was calculated. Results are compared with the calculated data for CaMS eye plaque loaded with Theragenics200 palladium-103 seeds and model 6711 iodine-125 seed. The air kerma strength of the IR06- 103Pd seed to deliver 85 Gy in apex of tumor in water medium was calculated to be 4.10 U/seed. Along the central axis of stainless steel plaque loaded with new 103Pd seeds in Acrylic insert, the dose reduction relative to water is 6.9% at 5 mm (apex). Removal of the Acrylic insert from the plaque (replacing with water) did not make significantly difference in dose reduction results (O.2%). The presence of the stainless steel backing results in dose enhancement near the plaque relative to water. Doses at points of interest are higher for ROPES eye plaque when compared to CaMS eye plaque. The dosimetric parameters calculated in this work for the new palladium seed, showed that in dosimetry point of view, the IR06-103Pd seed is suitable for use in brachytherapy. The effect of Acrylic insert on dose distribution is negligible and the main effect on dose reduction is due to the presence of stainless steel plaque backing. (author)

  3. Foil Face Seal Testing

    Science.gov (United States)

    Munson, John

    2009-01-01

    In the seal literature you can find many attempts by various researchers to adapt film riding seals to the gas turbine engine. None have been successful, potential distortion of the sealing faces is the primary reason. There is a film riding device that does accommodate distortion and is in service in aircraft applications, namely the foil bearing. More specifically a foil thrust bearing. These are not intended to be seals, and they do not accommodate large axial movement between shaft & static structure. By combining the 2 a unique type of face seal has been created. It functions like a normal face seal. The foil thrust bearing replaces the normal primary sealing surface. The compliance of the foil bearing allows the foils to track distortion of the mating seal ring. The foil seal has several perceived advantages over existing hydrodynamic designs, enumerated in the chart. Materials and design methodology needed for this application already exist. Also the load capacity requirements for the foil bearing are low since it only needs to support itself and overcome friction forces at the antirotation keys.

  4. Seal containment system

    International Nuclear Information System (INIS)

    Kugler, R.W.; Gerkey, K.S.; Kasner, W.H.

    1978-01-01

    An automated system for transporting nuclear fuel elements between fuel element assembly stations without contaminating the area outside the sealed assembly stations is described. The system comprises a plurality of assembly stations connected together by an elongated horizontal sealing mechanism and an automatic transport mechanism for transporting a nuclear fuel element in a horizontal attitude between the assembly stations while the open end of the fuel element extends through the sealing mechanism into the assembly station enclosure. The sealing mechanism allows the fuel element to be advanced by the transport mechanism while limiting the escape of radioactive particles from within the assembly station enclosure. 4 claims, 6 figures

  5. High Test Peroxide High Sealing Conical Seal, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — High Test Peroxide (HTP) Highly Compatible High Sealing Conical Seals are necessary for ground test operations and space based applications. Current conical seals...

  6. Sealed radioactive sources toolkit

    International Nuclear Information System (INIS)

    Mac Kenzie, C.

    2005-09-01

    The IAEA has developed a Sealed Radioactive Sources Toolkit to provide information to key groups about the safety and security of sealed radioactive sources. The key groups addressed are officials in government agencies, medical users, industrial users and the scrap metal industry. The general public may also benefit from an understanding of the fundamentals of radiation safety

  7. Seals and Scrolls.

    Science.gov (United States)

    Macaulay, Sara Grove

    2000-01-01

    Describes an art unit in which students sculpt a signature seal out of clay and use Chinese brush painting techniques to paint a scroll. Discusses the seal and its historical use in China. Lists materials needed and explains the procedure. (CMK)

  8. Flexible Seal Accommodates Part Mismatch

    Science.gov (United States)

    Bobb, I.

    1983-01-01

    Chain of plates embedded in flexible seal enables it to withstand side loading of 2,300 psi (116MPa) while sealing gap of up to 0.5 inch (13 mm) between cylindrical chamber wall and test fixture. Pressure-actuated seal along inner edge forces seal into contact even though cylinder wall becomes eccentric as cylinder pressure increases. Seal has many industrial applications, particularly where heat or pressure causes distortion of chamber being sealed.

  9. Brush seal performance measurement system

    OpenAIRE

    Aksoy, Serdar; Akşit, Mahmut Faruk; Aksit, Mahmut Faruk; Duran, Ertuğrul Tolga; Duran, Ertugrul Tolga

    2009-01-01

    Brush seals are rapidly replacing conventional labyrinth seals in turbomachinery applications. Upon pressure application, seal stiffness increases drastically due to frictional bristle interlocking. Operating stiffness is critical to determine seal wear life. Typically, seal stiffness is measured by pressing a curved shoe to brush bore. The static-unpressurized measurement is extrapolated to pressurized and high speed operating conditions. This work presents a seal stiffness measurement syste...

  10. Reactor vessel sealing plug

    International Nuclear Information System (INIS)

    Dooley, R.A.

    1986-01-01

    An apparatus is described for sealing a cold leg nozzle of a nuclear reactor pressure vessel from a remote location comprising: at least one sealing plug for mechanically sealing the nozzle from the inside of the reactor pressure vessel. The sealing plug includes a plate and a cone assembly having an end part receptive in the nozzle, the plate being axially moveable relative to the cone assembly. The plate and cone assembly have confronting bevelled edges defining an opening therebetween. A primary O-ring is disposed about the opening and is supported on the bevelled edges, the plate being guidably mounted to the cone assembly for movement toward the cone assembly to radially expand the primary O-ring into sealing engagement with the nozzle. A means is included for providing relative movement between the outer plate and the cone assembly

  11. SEALING SIMULATED LEAKS

    Energy Technology Data Exchange (ETDEWEB)

    Michael A. Romano

    2004-09-01

    This report details the testing equipment, procedures and results performed under Task 7.2 Sealing Simulated Leaks. In terms of our ability to seal leaks identified in the technical topical report, Analysis of Current Field Data, we were 100% successful. In regards to maintaining seal integrity after pigging operations we achieved varying degrees of success. Internal Corrosion defects proved to be the most resistant to the effects of pigging while External Corrosion proved to be the least resistant. Overall, with limitations, pressure activated sealant technology would be a viable option under the right circumstances.

  12. SRC seal testing

    Science.gov (United States)

    Miller, E. D.; Kohout, G. J.

    1973-01-01

    Small venthole drilled in semisealed silicon-controlled rectifier (SCR) cavity eliminates entrapped helium. Although these devices show slightly greater leak than those before lead installation, it is now possible to distinguish device with good hermetic seal from defective one.

  13. Turbine seal assembly

    Science.gov (United States)

    Little, David A.

    2013-04-16

    A seal assembly that limits gas leakage from a hot gas path to one or more disc cavities in a turbine engine. The seal assembly includes a seal apparatus that limits gas leakage from the hot gas path to a respective one of the disc cavities. The seal apparatus comprises a plurality of blade members rotatable with a blade structure. The blade members are associated with the blade structure and extend toward adjacent stationary components. Each blade member includes a leading edge and a trailing edge, the leading edge of each blade member being located circumferentially in front of the blade member's corresponding trailing edge in a direction of rotation of the turbine rotor. The blade members are arranged such that a space having a component in a circumferential direction is defined between adjacent circumferentially spaced blade members.

  14. [Sleep of Caspian seals].

    Science.gov (United States)

    Mukhametov, L M; Supin, A Ia; Poliakova, I G

    1984-01-01

    ECoG both hemispheres, EOG, neck EMG, ECG and electrical activity of olfactory bulbs were recorded in 4 free moving adult Caspean seals of both sexes. Their sleep on land and in water was compared. The wakefulness occupied 85,5 +/- 1,5% of total recording time, the slow wave sleep--12,8 +/- 1,4% and paradoxical sleep--1,7 +/- 0,2%. Unlike the dolphins, the Caspean seals possess no unihemispheric slow wave sleep. When the seals sleep on the land or on the water surface and do not change their posture for breathing they may breathe without awakening like the terrestrial mammals. But when the seals emerge or change their posture to get nostrils above the water they wake up briefly for respiration period.

  15. Core disruptive accident margin seal

    International Nuclear Information System (INIS)

    Golden, M.P.

    1979-01-01

    An apparatus for sealing the annulus defined within a substantially cylindrical rotatable riser assembly and plug combination of a nuclear reactor closure head is described. The apparatus comprises an inflatable sealing mechanism disposed in one portion of the riser assembly near the annulus such that upon inflation the sealing mechanism is radially actuated against the other portion of the riser assembly thereby sealing the annulus. The apparatus further comprises a connecting mechanism which places one end of the sealing mechanism in fluid communication with the reactor cover gas so that overpressurization of the reactor cover gas will increase the radial actuation of the sealing mechanism thus enhancing sealing of the annulus

  16. Ultra high vacuum seal arrangement

    Science.gov (United States)

    Flaherty, Robert

    1981-01-01

    Arrangement for demountably sealing two concentric metallic tubes in an ultra high vacuum system which facilitates remote actuation. A tubular seal includes integral spaced lips which circumferentially engage the metallic tubes. The lips plastically deform the metallic tubes by mechanical forces resulting from a martensite to austenite transformation of the tubular seal upon application of a predetermined temperature. The sealing force is released upon application of another temperature which causes a transformation from the stronger austenite to the weaker martensite. Use of a dual acting sealing ring and driving ring circumferentially contacting the sealing ring is particularly applicable to sealing larger diameter concentric metallic members.

  17. Titanium hermetic seals

    Science.gov (United States)

    Brow, Richard K.; Watkins, Randall D.

    1995-01-01

    Titanium is prenitrided by being heated in a nitrogen environment under conditions which give rise to the formation of a titanium-nitride surface layer on the titanium. Titanium thus prenitrided may be used in electrical components which are hermetically sealed using silicate glasses and standard glass sealing techniques. According to the method of the invention, alkali volatilization and formation of deleterious interfacial silicide are inhibited.

  18. Seed quality in informal seed systems

    NARCIS (Netherlands)

    Biemond, P.C.

    2013-01-01

    Keywords:     informal seed systems, seed recycling, seed quality, germination, seed pathology, seed health, seed-borne diseases, mycotoxigenic fungi, Fusarium verticillioides, mycotoxins, Vigna unguiculata, Zea mays, Nigeria.   Seed is a crucial input for agricultural

  19. Serum chemistry and antibodies against pathogens in antarctic fur seals, Weddell seals, crabeater seals, and Ross seals.

    Science.gov (United States)

    Tryland, Morten; Nymo, Ingebjørg H; Nielsen, Ole; Nordøy, Erling S; Kovacs, Kit M; Krafft, Bjørn A; Thoresen, Stein I; Åsbakk, Kjetil; Osterrieder, Klaus; Roth, Swaantje J; Lydersen, Christian; Godfroid, Jacques; Blix, Arnoldus S

    2012-07-01

    Information on health parameters, such as antibody prevalences and serum chemistry that can reveal exposure to pathogens, disease, and abnormal physiologic conditions, is scarce for Antarctic seal species. Serum samples from Antarctic fur seals (Arctocephalus gazella, n=88) from Bouvetøya (2000-2001 and 2001-2002), and from Weddell seals (Leptonychotes weddellii, n=20), Ross seals (Ommatophoca rossii, n=20), and crabeater seals (Lobodon carcinophagus, n=9) from the pack-ice off Queen Maud Land, Antarctica (2001) were analyzed for enzyme activity, and concentrations of protein, metabolites, minerals, and cortisol. Adult Antarctic fur seal males had elevated levels of total protein (range 64-99 g/l) compared to adult females and pups (range 52-79 g/l). Antarctic fur seals had higher enzyme activities of creatine kinase, lactate dehydrogenase, and amylase, compared to Weddell, Ross, and crabeater seals. Antibodies against Brucella spp. were detected in Weddell seals (37%), Ross seals (5%), and crabeater seals (11%), but not in Antarctic fur seals. Antibodies against phocine herpesvirus 1 were detected in all species examined (Antarctic fur seals, 58%; Weddell seals, 100%; Ross seals, 15%; and crabeater seals, 44%). No antibodies against Trichinella spp., Toxoplasma, or phocine distemper virus (PDV) were detected (Antarctic fur seals were not tested for PDV antibodies). Antarctic seals are challenged by reduced sea ice and increasing temperatures due to climate change, and increased anthropogenic activity can introduce new pathogens to these vulnerable ecosystems and represent a threat for these animals. Our data provide a baseline for future monitoring of health parameters of these Antarctic seal species, for tracking the impact of environmental, climatic, and anthropogenic changes in Antarctica over time.

  20. Upgrading inflatable door seals

    International Nuclear Information System (INIS)

    Sykes, T.M.; Metcalfe, R.; Welch, L.A.; Josefowich, J.M.

    1997-01-01

    Inflatable door seals are used for airlocks in CANDU stations. They have been a significant source of unreliability and maintenance cost. A program is underway to improve their performance and reliability, backed by environmental qualification testing. Only commercial products and suppliers existed in 1993. For historical reasons, these 'existing products' did not use the most durable material then available. In hindsight, neither had they been adapted nor optimized to combat conditions often experienced in the plants-sagging doors, damaged sealing surfaces, and many thousands of openings and closings per year. Initial attempts to involve the two existing suppliers in efforts to upgrade these seals were unsuccessful. Another suitable supplier had therefore to be found, and a 'new,' COG-owned seal developed; this was completed in 1997. This paper summarizes its testing, along with that of the two existing products. Resistance to aging has been improved significantly. Testing has shown that an accident can be safely withstood after 10 years of service or 40,000 openings-closings, whichever comes first. AECL's Fluid Sealing Technology Unit (FSTU) has invested in the special moulds, test fixtures and other necessary tooling and documentation required to begin commercial manufacture of this new quality product. Accordingly, as with FSTU's other nuclear products such as pump seals, the long-term supply of door seals to CANDU plants is now protected from many external uncertainties-e.g., commercial products being discontinued, materials being changed, companies going out of business. Manufacturing to AECL's detailed specifications is being subcontracted to the new supplier. FSTU is performing the quality surveillance, inspection, testing, and customer service activities concomitant with direct responsibility for supply to the plants. (author)

  1. Forged seal detection based on the seal overlay metric.

    Science.gov (United States)

    Lee, Joong; Kong, Seong G; Lee, Young-Soo; Moon, Ki-Woong; Jeon, Oc-Yeub; Han, Jong Hyun; Lee, Bong-Woo; Seo, Joong-Suk

    2012-01-10

    This paper describes a method for verifying the authenticity of a seal impression imprinted on a document based on the seal overlay metric, which refers to the ratio of an effective seal impression pattern and the noise in the neighborhood of the reference impression region. A reference seal pattern is obtained by taking the average of a number of high-quality impressions of a genuine seal. A target seal impression to be examined, often on paper with some background texts and lines, is segmented out from the background by an adaptive threshold applied to the histogram of color components. The segmented target seal impression is then spatially aligned with the reference by maximizing the count of matching pixels. Then the seal overlay metric is computed for the reference and the target. If the overlay metric of a target seal is below a predetermined limit for the similarity to the genuine, then the target is classified as a forged seal. To further reduce the misclassification rate, the seal overlay metric is adjusted by the filling rate, which reflects the quality of inked pattern of the target seal. Experiment results demonstrate that the proposed method can detect elaborate seal impressions created by advanced forgery techniques such as lithography and computer-aided manufacturing. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  2. Pool gateway seal

    International Nuclear Information System (INIS)

    Starr, J.A.; Steinert, L.A.

    1983-01-01

    A device for sealing a gateway between interconnectable pools in a nuclear facility comprising a frame supporting a liquid impermeable sheet positioned in a u-shaped gateway between the pools. An inflatable tube carried in a channel in the periphery of the frame and adjoining the gateway provides a seal therebetween when inflated. A restraining arrangement on the bottom edge of the frame is releasably engagable with an adjacent portion of the gateway to restrict the movement of the frame in the u-shaped gateway upon inflation of the tube, thereby enhancing the seal. The impermeable sheet is formed of an elastomer and thus is conformable to a liquid permeable supportive wall upon application of liquid pressure to the side of the sheet opposite the wall

  3. HMSRP Hawaiian Monk Seal Master Identification Records (seal)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains records of all individually identified Hawaiian monk seals since 1981. These seals were identified by PSD personnel and cooperating scientists...

  4. Structural Design and Sealing Performance Analysis of Biomimetic Sealing Ring

    Directory of Open Access Journals (Sweden)

    Chuanjun Han

    2015-01-01

    Full Text Available In order to reduce the failure probability of rubber sealing rings in reciprocating dynamic seal, a new structure of sealing ring based on bionics was designed. The biomimetic ring has three concave ridges and convex bulges on each side which are very similar to earthworms. Bulges were circularly designed and sealing performances of the biomimetic ring in both static seal and dynamic seal were simulated by FEM. In addition, effects of precompression, medium pressure, speed, friction coefficient, and material parameters on sealing performances were discussed. The results show that von Mises stress of the biomimetic sealing ring distributed symmetrically in no-pressure static sealing. The maximum von Mises stress appears on the second bulge of the inner side. High contact stress concentrates on left bulges. Von Mises stress distribution becomes uneven under medium pressure. Both von Mises stress and contact stress increase when precompression, medium pressure, and rubber hardness increase in static sealing. Biomimetic ring can avoid rolling and distortion in reciprocating dynamic seal, and its working life is much longer than O-ring and rectangular ring. The maximum von Mises stress and contact stress increase with the precompression, medium pressure, rubber hardness, and friction coefficient in reciprocating dynamic seal.

  5. Static seal for turbine engine

    Science.gov (United States)

    Salazar, Santiago; Gisch, Andrew

    2014-04-01

    A seal structure for a gas turbine engine, the seal structure including first and second components located adjacent to each other and forming a barrier between high and low pressure zones. A seal cavity is defined in the first and second components, the seal cavity extending to either side of an elongated gap extending generally in a first direction between the first and second components. A seal member is positioned within the seal cavity and spans across the elongated gap. The seal member includes first and second side edges extending into each of the components in a second direction transverse to the first direction, and opposing longitudinal edges extending between the side edges generally parallel to the first direction. The side edges include a groove formed therein for effecting a reduction of gas flow around the seal member at the side edges.

  6. Magnetically Actuated Seal, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — FTT proposes development of a magnetically actuated dynamic seal. Dynamic seals are used throughout the turbopump in high-performance, pump-fed, liquid rocket...

  7. Magnetically Actuated Seal, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — FTT proposes development of a magnetically actuated dynamic seal. Dynamic seals are used throughout the turbopump in high-performance, pump-fed, liquid rocket...

  8. Continuous improvement of pump seals

    International Nuclear Information System (INIS)

    Wong, W.; Eyvindson, A.; Rhodes, D.B.

    2003-01-01

    Pump seal reliability continues to be an area needing improvement and ongoing vigilance. Methods have been developed for identifying and assessing factors relating to seal performance, selecting the most relevant ones for a specific station, and then focusing on the most significant aspects and how to improve. Discussion invariably addresses maintenance practices, seal design, monitoring capabilities, operating conditions, transients, and pump and motor design. Success in reliability improvement requires ongoing dialogue among the station operators, pump manufacturers and seal designers. AECL CAN-seals lead the nuclear industry in reliability and seal life. They effectively save operators millions of dollars in outage time and person-rem. This paper describes some of the significant developments in AECL's ongoing program in seal R and D, as well as recent new installations following the most demanding seal qualification programs to date. (author)

  9. GOLD PRESSURE VESSEL SEAL

    Science.gov (United States)

    Smith, A.E.

    1963-11-26

    An improved seal between the piston and die member of a piston-cylinder type pressure vessel is presented. A layer of gold, of sufficient thickness to provide an interference fit between the piston and die member, is plated on the contacting surface of at least one of the members. (AEC)

  10. Four Sided Seal Tester

    Science.gov (United States)

    2009-07-01

    The Center for Advanced Food Technology School of Enviromental and Biological Sciences New Brunswick, NJ 08903 FTR 216 Defense Logistics Agency...specification for four sided seal tester as function of confinement plate distance” The following modifications were issued :  Jul 18, 2007 0013/01

  11. Detection of grey seal

    NARCIS (Netherlands)

    van Bleijswijk, J.; Begeman, L.; Witte, H.J.; IJsseldijk, L.L.; Brasseur, S.M.J.M.; Gröne, A.; Leopold, M.F.

    2014-01-01

    DNA was analysed from external wounds on 3 dead harbour porpoises Phocoena phocoena that were stranded in the Netherlands. Puncture wounds as well as the edges of large open wounds were sampled with sterile cotton swabs. With specific primers that target the mtDNA control region of grey seal

  12. Ultrasonic dip seal maintenance system

    International Nuclear Information System (INIS)

    Poindexter, A.M.; Ricks, H.E.

    1978-01-01

    Disclosed is a system for removing impurities from the surfaces of liquid dip seals and for wetting the metal surfaces of liquid dip seals in nuclear components. The system comprises an ultrasonic transducer that transmits ultrasonic vibrations along an ultrasonic probe to the metal and liquid surfaces of the dip seal thereby loosening and removing those impurities

  13. Failure analysis and seal life prediction for contacting mechanical seals

    Science.gov (United States)

    Sun, J. J.; He, X. Y.; Wei, L.; Feng, X.

    2008-11-01

    Fault tree analysis method was applied to quantitatively investigate the causes of the leakage failure of mechanical seals. It is pointed out that the change of the surface topography is the main reasons causing the leakage of mechanical seals under the condition of constant preloads. Based on the fractal geometry theory, the relationship between the surface topography and working time were investigated by experiments, and the effects of unit load acting on seal face on leakage path in a mechanical seal were analyzed. The model of predicting seal life of mechanical seals was established on the basis of the relationship between the surface topography and working time and allowable leakage. The seal life of 108 mechanical seal operating at the system of diesel fuel storage and transportation was predicted and the problem of the condition monitoring for the long-period operation of mechanical seal was discussed by this method. The research results indicate that the method of predicting seal life of mechanical seals is feasible, and also is foundation to make scheduled maintenance time and to achieve safe-reliability and low-cost operation for industrial devices.

  14. SU-E-T-458: Radiobiological Comparison of Single and Dual-Isotope Prostate Seed Implants.

    Science.gov (United States)

    Knaup, C; Mavroidis, P; Esquivel, C; Stathakis, S; Swanson, G; Papanikolaou, N

    2012-06-01

    Several isotopes are available for low dose-rate brachytherapy of the prostate. Currently, most implants use a single isotope. However, the use of dual-isotope implants may yield an advantageous combination of characteristics such as half-life and relative biological effectiveness. However, the use of dual-isotope implants complicates treatment planning and quality assurance. Do the benefits of dual-isotope implants outweigh the added difficulty? The goal of this work was to use a linear-quadratic model to compare single and dual-isotope implants. Ten patients were evaluated in this study. For each patient, six treatment plans were created with single or dual-isotope combinations of 1251, 103Pd and 131Cs. For each plan the prostate, urethra, rectum and bladder were contoured by a physician. The biologically effective dose was used to determine the tumor control probability and normal tissue complication probabilities for each plan. Each plan was evaluated using favorable, intermediate and unfavorable radiobiological parameters. The results of the radiobiological analysis were used to compare the single and dual-isotope treatment plans. Iodine-125 only implants were seen to be most affected by changes in tumor aggressiveness. Significant differences in organ response probabilities were seen at common dose levels. It was recognized that these differences were likely a result of suboptimal initial seed strengths. After adjusting the initial seed strength to maximize complication-free tumor control the differences between isotope combinations were minimal. This result was true even for unfavorable tumors. The objective of this work was to perform a radiobiologically based comparison of single and dual-isotope prostate seed implant plans. For all isotope combinations, the plans were improved by varying the initial seed strength. For the minimally-optimized treatment plans, no substantial differences in predicted treatment outcomes were seen among the different isotope

  15. SU-F-I-19: MRI Positive Contrast Visualization of Prostate Brachytherapy Seeds Using An Integrated Laplacian-Based Phase Processing

    Energy Technology Data Exchange (ETDEWEB)

    Soliman, A; Safigholi, H [Sunnybrook Research Institute, Toronto, ON (Canada); Sunnybrook Health Sciences Center, Toronto, ON (Canada); Nosrati, R [Sunnybrook Health Sciences Center, Toronto, ON (Canada); Ryerson University, Toronto, ON (Canada); Owrangi, A; Morton, G [Sunnybrook Health Sciences Center, Toronto, ON (Canada); University of Toronto, Toronto, ON (Canada); Song, W [Sunnybrook Research Institute, Toronto, ON (Canada); Sunnybrook Health Sciences Center, Toronto, ON (Canada); Ryerson University, Toronto, ON (Canada); University of Toronto, Toronto, ON (Canada)

    2016-06-15

    Purpose: To propose a new method that provides a positive contrast visualization of the prostate brachytherapy seeds using the phase information from MR images. Additionally, the feasibility of using the processed phase information to distinguish seeds from calcifications is explored. Methods: A gel phantom was constructed using 2% agar dissolved in 1 L of distilled water. Contrast agents were added to adjust the relaxation times. Four iodine-125 (Eckert & Ziegler SML86999) dummy seeds were placed at different orientations with respect to the main magnetic field (B0). Calcifications were obtained from a sheep femur cortical bone due to its close similarity to human bone tissue composition. Five samples of calcifications were shaped into different dimensions with lengths ranging between 1.2 – 6.1 mm.MR imaging was performed on a 3T Philips Achieva using an 8-channel head coil. Eight images were acquired at eight echo-times using a multi-gradient echo sequence. Spatial resolution was 0.7 × 0.7 × 2 mm, TR/TE/dTE = 20.0/2.3/2.3 ms and BW = 541 Hz/pixel. Complex images were acquired and fed into a two-step processing pipeline: the first includes phase unwrapping and background phase removal using Laplacian operator (Wei et al. 2013). The second step applies a specific phase mask on the resulting tissue phase from the first step to provide the desired positive contrast of the seeds and to, potentially, differentiate them from the calcifications. Results: The phase-processing was performed in less than 30 seconds. The proposed method has successfully resulted in a positive contrast of the brachytherapy seeds. Additionally, the final processed phase image showed difference between the appearance of seeds and calcifications. However, the shape of the seeds was slightly distorted compared to the original dimensions. Conclusion: It is feasible to provide a positive contrast of the seeds from MR images using Laplacian operator-based phase processing.

  16. Gulf and Dilmun Type seals

    DEFF Research Database (Denmark)

    Laursen, Steffen

    2011-01-01

    From around 2100 BC a glyptic tradition emerges in the Arabian Gulf, which is dependant on the well-established schools of the Indus Valley seal cutters. These circular hybrids of classic Harappan seals rapidly became popular amongst the merchants of Dilmun, centered on Bahrain Island. At first...... these Gulf Type‘ seals drew heavily on Indus Valley iconography and Indus script was occasionally employed in a pidgin-like manner. While the earliest circular seals incorporate features from Mesopotamian glyptic only to a lesser extent, this becomes a more important source of inspiration for later Dilmun...... Type seals....

  17. Hermetic Seal Leak Detection Apparatus

    Science.gov (United States)

    Kelley, Anthony R. (Inventor)

    2013-01-01

    The present invention is a hermetic seal leak detection apparatus, which can be used to test for hermetic seal leaks in instruments and containers. A vacuum tight chamber is created around the unit being tested to minimize gas space outside of the hermetic seal. A vacuum inducing device is then used to increase the gas chamber volume inside the device, so that a slight vacuum is pulled on the unit being tested. The pressure in the unit being tested will stabilize. If the stabilized pressure reads close to a known good seal calibration, there is not a leak in the seal. If the stabilized pressure reads closer to a known bad seal calibration value, there is a leak in the seal. The speed of the plunger can be varied and by evaluating the resulting pressure change rates and final values, the leak rate/size can be accurately calculated.

  18. Seals Having Textured Portions for Protection in Space Environments

    Science.gov (United States)

    Daniels, Christopher (Inventor); Garafolo, Nicholas (Inventor)

    2016-01-01

    A sealing construct for a space environment includes a seal-bearing object, a seal on the seal-bearing object, and a seal-engaging object. The seal includes a seal body having a sealing surface, and a textured pattern at the sealing surface, the textured pattern defining at least one shaded channel surface. The seal-engaging object is selectively engaged with the seal-bearing object through the seal. The seal-engaging object has a sealing surface, wherein, when the seal-engaging object is selectively engaged with the seal-bearing object, the sealing surface of the seal-engaging object engages the sealing surface of the seal, and the seal is compressed between the seal-bearing object and the seal-engaging object such that at least one shaded channel surface engages the sealing surface of the seal-engaging object.

  19. Radioactive waste sealing container

    International Nuclear Information System (INIS)

    Tozawa, S.; Kitamura, T.; Sugimoto, S.

    1984-01-01

    A low- to medium-level radioactive waste sealing container is constructed by depositing a foundation coating consisting essentially of zinc, cadmium or a zinc-aluminum alloy over a steel base, then coating an organic synthetic resin paint containing a metal phosphate over the foundation coating, and thereafter coating an acryl resin, epoxy resin, and/or polyurethane paint. The sealing container can consist of a main container body, a lid placed over the main body, and fixing members for clamping and fixing the lid to the main body. Each fixing member may consist of a material obtained by depositing a coating consisting essentially of cadmium or a zinc-aluminum alloy over a steel base

  20. Electromagnetic shaft seal

    International Nuclear Information System (INIS)

    Takahashi, Kenji.

    1994-01-01

    As an electromagnetic shaft seal, there are disposed outwarding electromagnetic induction devices having generating power directing to an electroconductive fluid as an object of sealing, and inwarding electromagnetic induction device added coaxially. There are disposed elongate rectangular looped first coils having a predetermined inner diameter, second coils having the same shape and shifted by a predetermined pitch relative to the first coil and third coil having the same shape and shifted by a predetermined pitch relative to the second coil respectively each at a predetermined inner diameter of clearance to the outwarding electromagnetic induction devices and the inwarding electromagnetic induction device. If the inwarding electromagnetic induction device and the outwarding electromagnetic induction device are operated, they are stopped at a point that the generating power of the former is equal with the sum of the generating power of the latter and a differential pressure. When three-phase AC is charged to the first coil, the second coil and the third coil successively, a force is generated in the advancing direction of the magnetic field in the electroconductive fluid by the similar effect to that of a linear motor, and the seal is maintained at high reliability. Moreover, the limit for the rotational angle of the shaft is not caused. (N.H.)

  1. Navy GTE seal development activity

    Science.gov (United States)

    Grala, Carl P.

    1993-10-01

    Under the auspices of the Integrated High Performance Turbine Engine Technology Initiative, the Naval Air Warfare Center conducts advanced development programs for demonstration in the next generation of air-breathing propulsion systems. Among the target technologies are gas path and lube oil seals. Two development efforts currently being managed by NAWCAD are the High Performance Compressor Discharge Film-Riding Face Seal and the Subsonic Core High Speed Air/Oil Seal. The High Performance Compressor Discharge Film-Riding Face Seal Program aims at reducing parasitic leakage through application of a film-riding face sea concept to the compressor discharge location of a Phase 2 IHPTET engine. An order-of-magnitude leakage reduction relative to current labyrinth seal configurations is expected. Performance goals for these seals are (1) 1200 F air temperature, (2) 800 feet-per-second surface velocity, and (3) 600 SPI differential pressure. The two designs chosen for fabrication and rig test are a spiral groove and a Rayleigh step seal. Rig testing is currently underway. The Subsonic Core High Speed Air/Oil Seal Program is developing shaft-to-ground seals for next-generation propulsion systems that will minimize leakage and provide full life. Significantly higher rotor speeds and temperatures will be experienced. Technologies being exploited include, hydrodynamic lift assist features, ultra light weight designs, and improved cooling schemes. Parametric testing has been completed; a final seal design is entering the endurance test phase.

  2. Closure and Sealing Design Calculation

    International Nuclear Information System (INIS)

    T. Lahnalampi; J. Case

    2005-01-01

    The purpose of the ''Closure and Sealing Design Calculation'' is to illustrate closure and sealing methods for sealing shafts, ramps, and identify boreholes that require sealing in order to limit the potential of water infiltration. In addition, this calculation will provide a description of the magma that can reduce the consequences of an igneous event intersecting the repository. This calculation will also include a listing of the project requirements related to closure and sealing. The scope of this calculation is to: summarize applicable project requirements and codes relating to backfilling nonemplacement openings, removal of uncommitted materials from the subsurface, installation of drip shields, and erecting monuments; compile an inventory of boreholes that are found in the area of the subsurface repository; describe the magma bulkhead feature and location; and include figures for the proposed shaft and ramp seals. The objective of this calculation is to: categorize the boreholes for sealing by depth and proximity to the subsurface repository; develop drawing figures which show the location and geometry for the magma bulkhead; include the shaft seal figures and a proposed construction sequence; and include the ramp seal figure and a proposed construction sequence. The intent of this closure and sealing calculation is to support the License Application by providing a description of the closure and sealing methods for the Safety Analysis Report. The closure and sealing calculation will also provide input for Post Closure Activities by describing the location of the magma bulkhead. This calculation is limited to describing the final configuration of the sealing and backfill systems for the underground area. The methods and procedures used to place the backfill and remove uncommitted materials (such as concrete) from the repository and detailed design of the magma bulkhead will be the subject of separate analyses or calculations. Post-closure monitoring will not

  3. TECHNOLOGY ROADMAPPING FOR IAEA SEALS.

    Energy Technology Data Exchange (ETDEWEB)

    HOFFHEINS,B.; ANNESE,C.; GOODMAN,M.; OCONNOR,W.; GUSHUE,S.; PEPPER,S.

    2003-07-13

    In the fall of 2002, the U.S. Support Program (USSP) initiated an effort to define a strategy or ''roadmap'' for future seals technologies and to develop a generalized process for planning safeguards equipment development, which includes seals and other safeguards equipment. The underlying objectives of the USSP include becoming more proactive than reactive in addressing safeguards equipment needs, helping the IAEA to maintain an inventory of cost-effective, reliable, and effective safeguards equipment, establishing a long-term planning horizon, and securing IAEA ownership in the process of effective requirements definition and timely transitioning of new or improved systems for IAEA use. At an initial workshop, seals, their functions, performance issues, and future embodiments were discussed in the following order: adhesive seals, metal seals, passive and active loop seals, ultrasonic seals, tamper indicating enclosures (including sample containers, equipment enclosures, and conduits). Suggested improvements to these technologies focused largely on a few themes: (1) The seals must be applied quickly, easily, and correctly; (2) Seals and their associated equipment should not unduly add bulk or weight to the inspectors load; (3) Rapid, in-situ verifiability of seals is desirable; and (4) Seal systems for high risk or high value applications should have two-way, remote communications. Based upon these observations and other insights, the participants constructed a skeletal approach for seals technology planning. The process begins with a top-level review of the fundamental safeguards requirements and extraction of required system features, which is followed by analysis of suitable technologies and identification of technology gaps, and finally by development of a planning schedule for system improvements and new technology integration. Development of a comprehensive procedure will require the partnership and participation of the IAEA. The

  4. TECHNOLOGY ROADMAPPING FOR IAEA SEALS

    International Nuclear Information System (INIS)

    HOFFHEINS, B.; ANNESE, C.; GOODMAN, M.; OCONNOR, W.; GUSHUE, S.; PEPPER, S.

    2003-01-01

    In the fall of 2002, the U.S. Support Program (USSP) initiated an effort to define a strategy or ''roadmap'' for future seals technologies and to develop a generalized process for planning safeguards equipment development, which includes seals and other safeguards equipment. The underlying objectives of the USSP include becoming more proactive than reactive in addressing safeguards equipment needs, helping the IAEA to maintain an inventory of cost-effective, reliable, and effective safeguards equipment, establishing a long-term planning horizon, and securing IAEA ownership in the process of effective requirements definition and timely transitioning of new or improved systems for IAEA use. At an initial workshop, seals, their functions, performance issues, and future embodiments were discussed in the following order: adhesive seals, metal seals, passive and active loop seals, ultrasonic seals, tamper indicating enclosures (including sample containers, equipment enclosures, and conduits). Suggested improvements to these technologies focused largely on a few themes: (1) The seals must be applied quickly, easily, and correctly; (2) Seals and their associated equipment should not unduly add bulk or weight to the inspectors' load; (3) Rapid, in-situ verifiability of seals is desirable; and (4) Seal systems for high risk or high value applications should have two-way, remote communications. Based upon these observations and other insights, the participants constructed a skeletal approach for seals technology planning. The process begins with a top-level review of the fundamental safeguards requirements and extraction of required system features, which is followed by analysis of suitable technologies and identification of technology gaps, and finally by development of a planning schedule for system improvements and new technology integration. Development of a comprehensive procedure will require the partnership and participation of the IAEA. The presentation will include a

  5. Seed quality in informal seed systems

    OpenAIRE

    Biemond, P.C.

    2013-01-01

    Keywords:     informal seed systems, seed recycling, seed quality, germination, seed pathology, seed health, seed-borne diseases, mycotoxigenic fungi, Fusarium verticillioides, mycotoxins, Vigna unguiculata, Zea mays, Nigeria.   Seed is a crucial input for agricultural production. Approximately 80% of the smallholder farmers in Africa depend for their seed on the informal seed system, consisting of farmers involved in selection, production and dissemination of seed. The la...

  6. Sealing of rock fractures

    International Nuclear Information System (INIS)

    Pusch, R.; Erlstroem, M.; Boergesson, L.

    1985-12-01

    The major water-bearing fractures in granite usually from fairly regular sets but the extension and degree of connectivity is varying. This means that only a few fractures that are interconnected with the deposition holes and larger water-bearing structures in a HLW repository are expected and if they can be identified and cut off through sealing it would be possible to improve the isolation of waste packages very effectively. Nature's own fracture sealing mechanisms may be simulated and a survey of the involved processes actually suggests a number of possible filling methods and substances. Most of them require high temperature and pressure and correspondingly sophisticated techniques, but some are of potential interest for immediate application with rather moderate effort. Such a technique is to fill the fractures with clayey substances which stay flexible and low-permeable provided that they remain physically and chemically intact. It is demonstrated in the report that effective grouting requires a very low viscosity and shear strength of the substance and this can be achieved by mechanical agitation as demonstrated in this report. Thus, by superimposing static pressure and shear waves induced by percussion hammering at a suitable frequency, clays and fine-grained silts as well as cement can be driven into fractures with an average aperture as small as 0.1 mm. Experiments were made in the laboratory using concrete and steel plates, and a field pilot test was also conducted under realistic conditions on site in Stripa. They all demonstrated the practicality of the 'dynamic injection technique' and that the fluid condition of the grouts yielded complete filling of the injected space to a considerable distance from the injection point. The field test indicated a good sealing ability as well as a surprisingly high resistance to erosion and piping. (author)

  7. Seed quality in informal seed systems

    NARCIS (Netherlands)

    Biemond, P.C.

    2013-01-01

    Keywords: informal seed systems, seed recycling, seed quality, germination, seed pathology, seed health, seed-borne diseases, mycotoxigenic fungi, Fusarium verticillioides, mycotoxins, Vigna unguiculata, Zea mays, Nigeria.

    Seed is a crucial input for agricultural production.

  8. Non Destructive Seal Testing Polymeric Tray

    National Research Council Canada - National Science Library

    Bruins, Henderikus B

    2006-01-01

    .... The ND tester is based on a static compression force that reduces the volume of the tray and creates an internal pressure inside the tray and exposes the seal to forces that open the seal if the seal...

  9. The effect of the radial function on I-125 seeds used for permanent prostate implantation

    International Nuclear Information System (INIS)

    Pickett, Barby; Pouliot, Jean

    2004-01-01

    The purpose of this study was to evaluate the integrity of eight commercially-available low-activity Iodine-125 ( 125 I) seeds for their radial function g(r) and its effect on the dose delivered to the adjacent critical structures when used in permanent prostate implants (PPI). Ten previously treated patients were retrospectively used in this comparison. The Amersham Health Oncura seed was used to peripherally design an isodose distribution with urethral and anterior rectal wall sparing. Plan criteria included minimum coverage of 144 Gy to the planning target volume (PTV), ≤ 70% dose to 150% of the PTV volume (V150-PTV), and the quantity of needles ≤ 70% of the size of the PTV, in cc. Upon completion of the Oncura plan, the seed type was changed and the activity was adjusted until the V100-PTV for each of the other 7 seed types matched the V100-PTV defined by the Oncura seed. Computed tomography (CT)-based postimplant dosimetry was used to determine the dose to 40% (D40) of the bulb of the penis (in Gy). Dose-volume histograms (DVH) were used to evaluate the differences to V100 (in %) and D40 (in Gy) of the anterior rectal wall and bulb of the penis, and V100 (in %) of the urethra. The data was tabulated. Radioactive 125 I sources included in this study were 125 I Source 2301 (Best); I-Plant (MedTech), IoGold (Mentor), Oncura (Amersham Health), ProstaSeed (UroCor), SelectSeed (Nucletron), SourceTech (Bard), and Symmetra (UroMed). The sizes of the PTV for the 10 patients ranged from 18.82 cc to 48.99 cc. The Oncura seed was used as the reference seed and all other seed types were normalized to it for data comparison. It was determined that the dose rate constant (xwedge) and anisotropy factor (phi) contribute to the activity needed to achieve comparable V100-PTV doses, but a strong dependence on the radial function g(r) was found to effect the doses to the critical structures studied. Values of g(r) at 4 cm were calculated and the IoGold and SourceTech seeds

  10. Repository Closure and Sealing Approach

    International Nuclear Information System (INIS)

    A.T. Watkins

    2000-01-01

    The scope of this analysis will be to develop the conceptual design of the closure seals and their locations in the Subsurface Facilities. The design will be based on the recently established program requirements for transitioning to the Site Recommendation (SR) design as outlined by ''Approach to Implementing the Site Recommendation Baseline'' (Stroupe 2000) and the ''Monitored Geologic Repository Project Description Document'' (CRWMS M andO 1999b). The objective of this analysis will be to assist in providing a description for the Subsurface Facilities System Description Document, Section 2 and finally to document any conclusions reached in order to contribute and provide support to the SR. This analysis is at a conceptual level and is considered adequate to support the SR design. The final closure barriers and seals for the ventilation shafts, and the north and south ramps will require these openings to be permanently sealed to limit excessive air and water inflows and prevent human intrusion. The major tasks identified with closure in this analysis are: (1) Developing the overall subsurface seal layout and identifying design and operational interfaces for the Subsurface Facilities. (2) Summarizing the general site conditions and general rock characteristic with respect to seal location and describing the seal selected. (3) Identify seal construction materials, methodology of construction and strategic locations including design of the seal and plugs. (4) Discussing methods to prevent human intrusion

  11. High temperature autoclave vacuum seals

    Science.gov (United States)

    Hoffman, J. R.; Simpson, W. G.; Walker, H. M.

    1971-01-01

    Aluminum sheet forms effective sealing film at temperatures up to 728 K. Soft aluminum wire rings provide positive seal between foil and platen. For applications at temperatures above aluminum's service temperature, stainless steel is used as film material and copper wire as sealant.

  12. Cryogenic Pressure Seal for Wires

    Science.gov (United States)

    Ciana, J. J.

    1984-01-01

    High-pressure-seal formed by forcing polyurethane into space surrounding wire or cable in special fitting. Wire or cable routed through fitting then through a tightly fitting cap. Wire insulation left intact. Cap filled with sealant and forced onto the fitting: this pushes sealant into fitting so it seals wire or cable in fitting as well as in cap.

  13. Rotating plug bearing and seal

    International Nuclear Information System (INIS)

    Wade, E.E.

    1977-01-01

    Disclosed is a bearing and seal structure for nuclear reactors utilizing rotating plugs above the nuclear reactor vessel. The structure permits lubrication of bearings and seals of the rotating plugs without risk of the lubricant draining into the reactor vessel below. The structure permits lubrication by utilizing a rotating outer race bearing. 19 claims, 3 figures

  14. Seals. Grades 3-6.

    Science.gov (United States)

    New England Aquarium, Boston, MA.

    Explanations of a marine mammal rescue program and information on seals and sea lions are presented in this curriculum package for intermediate grade teachers. Activities are highlighted which focus on the natural history of harbor seals. This unit contains: (1) pre-trip activities (including fact sheets and worksheets on the different types of…

  15. Aerodynamic seals for rotary machine

    Science.gov (United States)

    Bidkar, Rahul Anil; Cirri, Massimiliano; Thatte, Azam Mihir; Williams, John Robert

    2016-02-09

    An aerodynamic seal assembly for a rotary machine includes multiple sealing device segments disposed circumferentially intermediate to a stationary housing and a rotor. Each of the segments includes a shoe plate with a forward-shoe section and an aft-shoe section having multiple labyrinth teeth therebetween facing the rotor. The sealing device segment also includes multiple flexures connected to the shoe plate and to a top interface element, wherein the multiple flexures are configured to allow the high pressure fluid to occupy a forward cavity and the low pressure fluid to occupy an aft cavity. Further, the sealing device segments include a secondary seal attached to the top interface element at one first end and positioned about the flexures and the shoe plate at one second end.

  16. Turbine and Structural Seals Team Facilities

    Data.gov (United States)

    Federal Laboratory Consortium — Seals Team Facilities conceive, develop, and test advanced turbine seal concepts to increase efficiency and durability of turbine engines. Current projects include...

  17. Tamper tape seals

    International Nuclear Information System (INIS)

    Wright, B.W.; Undem, H.A.

    1994-07-01

    Tamper tapes are appealing for many applications due to their ease of use and relative robustness. Applications include seals for temporary area denial, protection of sensitive equipment, chain-of-custody audit trails, and inventory control practices. A next generation of adhesive tamper tapes is being developed that combines the best features of commercially available devices with additional state-of-the-art features in tamper indication, tamper-resistance, and counterfeit-resistance. The additional features are based on U.S. Department of Energy (DOE) research and development (R ampersand D) activities that were originally associated with preparations for the Strategic Arms Reduction Treaty (START). New features include rapid-set, chemical-cure adhesive systems that allow user-friendly application and layered levels of counterfeit-resistance based on unique open-quotes fingerprintclose quotes characteristics that can be accessed as desired

  18. High pressure mechanical seal

    Science.gov (United States)

    Babel, Henry W. (Inventor); Anderson, Raymond H. (Inventor)

    1996-01-01

    A relatively impervious mechanical seal is formed between the outer surface of a tube and the inside surface of a mechanical fitting of a high pressure fluid or hydraulic system by applying a very thin soft metal layer onto the outer surface of the hard metal tube and/or inner surface of the hard metal fitting. The thickness of such thin metal layer is independent of the size of the tube and/or fittings. Many metals and alloys of those metals exhibit the requisite softness, including silver, gold, tin, platinum, indium, rhodium and cadmium. Suitably, the coating is about 0.0025 millimeters (0.10 mils) in thickness. After compression, the tube and fitting combination exhibits very low leak rates on the order or 10.sup.-8 cubic centimeters per second or less as measured using the Helium leak test.

  19. Radioactive seed localization compared with wire-guided localization of non-palpable breast carcinoma in breast conservation surgery- the first experience in the United Kingdom.

    Science.gov (United States)

    Milligan, Robert; Pieri, Andrew; Critchley, Adam; Peace, Richard; Lennard, Tom; O'Donoghue, J M; Howitt, Rachel; Nicholson, Stewart; Cain, Henry; Petrides, George; Sibal, Nidhi

    2018-01-01

    In the UK, guidewires have traditionally been used for localization of non-palpable breast lesions in patients undergoing breast conservation surgery (BCS). Radioactive seed localization (RSL) using Iodine-125 seeds is an alternative localization method and involves inserting a titanium capsule, containing radioactive Iodine-125, into the breast lesion. We aim to demonstrate feasibility of RSL compared with guidewire-localization (GWL) for BCS in the UK. Data were collected on 100 patients with non-palpable unifocal invasive carcinoma of the breast undergoing GWL WLE prior to the introduction of RSL and the first 100 patients treated with RSL WLE. Statistical comparisons were made using Χ 2 -squared analysis or unpaired two-sample t-test. Significance was determined to be at p ≤ 0.05. Mean total tumour size was 19.44 mm (range: 5-55) in the GWL group and 18.61 mm (range: 3.8-59) in the RSL group (p = 0.548), while mean total specimen excision weight was significantly lower in the RSL group; 31.55 g (range: 4.5-112) vs 37.42 g (range: 7.8-157.1) (p = 0.018). Although 15 patients had inadequate surgical resection margins in the GWL group compared the 13 in the RSL group (15 vs 13%, respectively, p = 0.684), 10 of the patients in the GWL group had invasive carcinoma present resulting in at least one positive margin compared with only 3 patients in the RSL group (10 vs 3%, respectively, p = 0.045). In this study, RSL is shown to be non-inferior to the use of GWL for non-palpable carcinoma in patients undergoing BCS and we suggest that it could be introduced successfully in other breast units. Advances in knowledge: Here we have demonstrated the use of RSL localization results in significant lower weight resection specimens of breast carcinoma when compared with a matched group using GWL, without any significant differences in oncological outcome between the groups.

  20. Robotic seeding

    DEFF Research Database (Denmark)

    Pedersen, Søren Marcus; Fountas, Spyros; Sørensen, Claus Aage Grøn

    2017-01-01

    Agricultural robotics has received attention for approximately 20 years, but today there are only a few examples of the application of robots in agricultural practice. The lack of uptake may be (at least partly) because in many cases there is either no compelling economic benefit......, or there is a benefit but it is not recognized. The aim of this chapter is to quantify the economic benefits from the application of agricultural robots under a specific condition where such a benefit is assumed to exist, namely the case of early seeding and re-seeding in sugar beet. With some predefined assumptions...... with regard to speed, capacity and seed mapping, we found that among these two technical systems both early seeding with a small robot and re-seeding using a robot for a smaller part of the field appear to be financially viable solutions in sugar beet production....

  1. Rim seal arrangement having pumping feature

    Science.gov (United States)

    Lee, Ching-Pang; Myers, Caleb

    2017-04-25

    A rim seal arrangement for a gas turbine engine includes a first seal face on a rotor component, and a second seal face on a stationary annular rim centered about a rotation axis of the rotor component. The second seal face is spaced from the first seal face along an axial direction to define a seal gap. The seal gap is located between a radially outer hot gas path and a radially inner rotor cavity. The first seal face has a plurality of circumferentially spaced depressions, each having a depth in an axial direction and extending along a radial extent of the first seal face. The depressions influence flow in the seal gap such that during rotation of the rotor component, fluid in the seal gap is pumped in a radially outward direction to prevent ingestion of a gas path fluid from the hot gas path into the rotor cavity.

  2. Gas chromatograph analysis on closed air and nitrogen oxide storage atmospheres of recalcitrant seeds of Quercus Alba

    Science.gov (United States)

    Storage of recalcitrant seeds remains an unsolved problem. This study investigated the quantitative gas analysis of nitrous oxide (N2O) and air atmospheres on the recalcitrant seeds of Quercus alba by using gas chromatograph. Ten seeds were placed in each sealed atmospheric system of air and 98/2% N...

  3. Leak detection of KNI seals

    International Nuclear Information System (INIS)

    Baranyai, G.; Peter, A.; Windberg, P.

    1990-03-01

    In Unit 3 and 4 of the Paks Nuclear Power Plant, Hungary, KNI type seals are used as lead-throughs with conical nickel sealing rings. Their failure can be critical for the operation of the reactor. An Acoustical Leak Detection System (ALDS) was constructed and tested for the operational testing of the seals. Some individual papers are presented in this collection on the calibration and testing of the ALDS intended to be placed on the top of the reactor vessels. The papers include simulation measurements of Unit 3 of NPP, laboratory experiments, evaluation of measurements, and further development needs with the ALDS. (R.P.) 50 figs.; 19 tabs

  4. Seed regulations and local seed systems

    NARCIS (Netherlands)

    Louwaars, N.

    2000-01-01

    Seed regulations have been introduced in most countries based on the development of formal seed production. Concerns about seed quality and about the varietal identity of the seeds have commonly led to seed laws. However, formal regulations are often inappropriate for informal seed systems, which

  5. 7 CFR 29.35 - Lot seal.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Lot seal. 29.35 Section 29.35 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... INSPECTION Regulations Definitions § 29.35 Lot seal. A seal approved by the Director for sealing lots of...

  6. 7 CFR 29.34 - Sample seal.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Sample seal. 29.34 Section 29.34 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... INSPECTION Regulations Definitions § 29.34 Sample seal. A seal approved by the Director for sealing official...

  7. Design considerations for mechanical face seals

    Science.gov (United States)

    Ludwig, L. P.; Greiner, H. F.

    1980-01-01

    Two companion reports deal with design considerations for improving performance of mechanical face seals, one of family of devices used in general area of fluid sealing of rotating shafts. One report deals with basic seal configuration and other with lubrication of seal.

  8. Alaska Harbor Seal Glacial Surveys

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Floating glacial ice serves as a haul-out substrate for a significant number (10-15%) of Alaskan harbor seals, and thus surveying tidewater glacial fjords is an...

  9. Northern Fur Seal Food Habits

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains food habits samples, usually scats, collected opportunistically on northern fur seal rookeries and haulouts in Alaska from 1987 to present....

  10. M1 Abrams Seal Ring

    National Research Council Canada - National Science Library

    2004-01-01

    .... The 3.650-inch-diameter, 0.500-inch-wide seal, made of wrought A-286 nickel-iron super alloy, is difficult to clamp securely during machining, making it a challenge to maintain required roundness tolerances...

  11. Seals Research at AlliedSignal

    Science.gov (United States)

    Ullah, M. Rifat

    1996-01-01

    A consortium has been formed to address seal problems in the Aerospace sector of Allied Signal, Inc. The consortium is represented by makers of Propulsion Engines, Auxiliary Power Units, Gas Turbine Starters, etc. The goal is to improve Face Seal reliability, since Face Seals have become reliability drivers in many of our product lines. Several research programs are being implemented simultaneously this year. They include: Face Seal Modeling and Analysis Methodology; Oil Cooling of Seals; Seal Tracking Dynamics; Coking Formation & Prevention; and Seal Reliability Methods.

  12. Brush Seals for Improved Steam Turbine Performance

    Science.gov (United States)

    Turnquist, Norman; Chupp, Ray; Baily, Fred; Burnett, Mark; Rivas, Flor; Bowsher, Aaron; Crudgington, Peter

    2006-01-01

    GE Energy has retrofitted brush seals into more than 19 operating steam turbines. Brush seals offer superior leakage control compared to labyrinth seals, owing to their compliant nature and ability to maintain very tight clearances to the rotating shaft. Seal designs have been established for steam turbines ranging in size from 12 MW to over 1200 MW, including fossil, nuclear, combined-cycle and industrial applications. Steam turbines present unique design challenges that must be addressed to ensure that the potential performance benefits of brush seals are realized. Brush seals can have important effects on the overall turbine system that must be taken into account to assure reliable operation. Subscale rig tests are instrumental to understanding seal behavior under simulated steam-turbine operating conditions, prior to installing brush seals in the field. This presentation discusses the technical challenges of designing brush seals for steam turbines; subscale testing; performance benefits of brush seals; overall system effects; and field applications.

  13. Sealed can of spent fuel

    International Nuclear Information System (INIS)

    Suzuki, Yasuyuki.

    1976-01-01

    Object: To provide a seal plug cover with a gripping portion fitted to a canning machine and a gripping portion fitted to a gripper of the same configuration as a fuel body for handling the fuel body so as to facilitate the handling work. Structure: A sealed can comprises a vessel and a seal plug cover, said cover being substantially in the form of a bottomed cylinder, which is slipped on the vessel and air-tightly secured by a fastening bolt between it and a flange. The spent fuel body is received into the vessel together with coolant during the step of canning operation. Said seal plug cover has two gripping portions, one for opening and closing the plug cover of the canning machine as an exclusive use member, the other being in the form of a hook-shaped peripheral groove, whereby the gripping portions may be effectively used using the same gripper when the spent fuel body is transported while being received in the sealed can or when the fuel body is removed from the sealed can. (Kawakami, Y.)

  14. Reusable, tamper-indicating seal

    International Nuclear Information System (INIS)

    Ryan, M.J.

    1978-01-01

    A reusable, tamper-indicating seal is comprised of a drum confined within a fixed body and rotatable in one direction therewithin, the top of the drum constituting a tray carrying a large number of small balls of several different colors. The fixed body contains parallel holes for looping a seal wire therethrough. The base of the drums carries cams adapted to coact with cam followers to lock the wire within the seal at one angular position of the drum. A channel in the fixed body, visible from outside the seal, adjacent the tray constitutes a segregated location for a small plurality of the colored balls. A spring in the tray forces colored balls into the segregated location at one angular position of the drum, further rotation securing the balls in position and the wires in the seal. A wedge-shaped plough removes the balls from the segregated location, at a different angular position of the drum, the wire being unlocked at the same postion. A new pattern of colored balls will appear in the segregated location when the seal is relocked

  15. Hydrodynamic perception in true seals (Phocidae) and eared seals (Otariidae).

    Science.gov (United States)

    Hanke, Wolf; Wieskotten, Sven; Marshall, Christopher; Dehnhardt, Guido

    2013-06-01

    Pinnipeds, that is true seals (Phocidae), eared seals (Otariidae), and walruses (Odobenidae), possess highly developed vibrissal systems for mechanoreception. They can use their vibrissae to detect and discriminate objects by direct touch. At least in Phocidae and Otariidae, the vibrissae can also be used to detect and analyse water movements. Here, we review what is known about this ability, known as hydrodynamic perception, in pinnipeds. Hydrodynamic perception in pinnipeds developed convergently to the hydrodynamic perception with the lateral line system in fish and the sensory hairs in crustaceans. So far two species of pinnipeds, the harbour seal (Phoca vitulina) representing the Phocidae and the California sea lion (Zalophus californianus) representing the Otariidae, have been studied for their ability to detect local water movements (dipole stimuli) and to follow hydrodynamic trails, that is the water movements left behind by objects that have passed by at an earlier point in time. Both species are highly sensitive to dipole stimuli and can follow hydrodynamic trails accurately. In the individuals tested, California sea lions were clearly more sensitive to dipole stimuli than harbour seals, and harbour seals showed a superior trail following ability as compared to California sea lions. Harbour seals have also been shown to derive additional information from hydrodynamic trails, such as motion direction, size and shape of the object that caused the trail (California sea lions have not yet been tested). The peculiar undulated shape of the harbour seals' vibrissae appears to play a crucial role in trail following, as it suppresses self-generated noise while the animal is swimming.

  16. Development of borehole sealing technology

    International Nuclear Information System (INIS)

    Shimada, Kuniaki; Abe, Kenichi; Tanada, Masuakira; Fujii, Mitsuru

    2004-03-01

    As a part of the geoscientific research in JNC Tono Geoscience Center, we are conducting the borehole investigation as a method of surveying techniques to gain an understanding of geological environment characterization (geology/geological structure, rock hydraulic characteristics, ground water geochemical characteristics and rock mechanics) from surface to deep underground. The borehole for the borehole investigation is used for monitoring hole after the borehole investigation. Since the borehole may act as a passage of groundwater flow and disturb the geological environment artificially, it has to be sealed in finally. Moreover, the hydraulic testing and the geochemical analysis of groundwater that be conducted in the zones injected some kind of lost circulation materials might be impacted on the accuracy of test result. The actual technologies regarding to these themes was researched and evaluated. In the second step, clarification of problems and procedure of R and D for solution of these problems was examined. In order to estimate the effect of lost circulation materials on hydraulic testing, a laboratory test of borehole behavior was performed using a scale model that consisted of a borehole and a water-loss zone. In this test, we found out that the lost circulation material was desorbed from the water-loss zone by back-flow action. It was proved by the test that there is little influence from lost circulation materials on hydraulic testing. Investigation regarding borehole sealing technology was conducted in literature search and interview to overseas researchers. In consequent, three kinds of materials - bentonite clay, bentonite pellet, and ethanol bentonite, were selected as effective sealing material. Moreover, five kinds of methods were selected as effective sealing methods. In water permeability test of sealing material, three kinds of sealing materials indicated lower permeability - order of 10 -11 m/sec, and it was evaluated that it could be worked

  17. Dual-head gamma camera system for intraoperative localization of radioactive seeds

    International Nuclear Information System (INIS)

    Arsenali, B; Viergever, M A; Gilhuijs, K G A; De Jong, H W A M; Beijst, C; Dickerscheid, D B M

    2015-01-01

    Breast-conserving surgery is a standard option for the treatment of patients with early-stage breast cancer. This form of surgery may result in incomplete excision of the tumor. Iodine-125 labeled titanium seeds are currently used in clinical practice to reduce the number of incomplete excisions. It seems likely that the number of incomplete excisions can be reduced even further if intraoperative information about the location of the radioactive seed is combined with preoperative information about the extent of the tumor. This can be combined if the location of the radioactive seed is established in a world coordinate system that can be linked to the (preoperative) image coordinate system. With this in mind, we propose a radioactive seed localization system which is composed of two static ceiling-suspended gamma camera heads and two parallel-hole collimators. Physical experiments and computer simulations which mimic realistic clinical situations were performed to estimate the localization accuracy (defined as trueness and precision) of the proposed system with respect to collimator-source distance (ranging between 50 cm and 100 cm) and imaging time (ranging between 1 s and 10 s). The goal of the study was to determine whether or not a trueness of 5 mm can be achieved if a collimator-source distance of 50 cm and imaging time of 5 s are used (these specifications were defined by a group of dedicated breast cancer surgeons). The results from the experiments indicate that the location of the radioactive seed can be established with an accuracy of 1.6 mm  ±  0.6 mm if a collimator-source distance of 50 cm and imaging time of 5 s are used (these experiments were performed with a 4.5 cm thick block phantom). Furthermore, the results from the simulations indicate that a trueness of 3.2 mm or less can be achieved if a collimator-source distance of 50 cm and imaging time of 5 s are used (this trueness was achieved for all 14 breast phantoms which

  18. Spray sealing: A breakthrough in integral fuel tank sealing technology

    Science.gov (United States)

    Richardson, Martin D.; Zadarnowski, J. H.

    1989-11-01

    In a continuing effort to increase readiness, a new approach to sealing integral fuel tanks is being developed. The technique seals potential leak sources by spraying elastomeric materials inside the tank cavity. Laboratory evaluations project an increase in aircraft supportability and reliability, an improved maintainability, decreasing acquisition and life cycle costs. Increased usable fuel volume and lower weight than conventional bladders improve performance. Concept feasibility was demonstrated on sub-scale aircraft fuel tanks. Materials were selected by testing sprayable elastomers in a fuel tank environment. Chemical stability, mechanical properties, and dynamic durability of the elastomer are being evaluated at the laboratory level and in sub-scale and full scale aircraft component fatigue tests. The self sealing capability of sprayable materials is also under development. Ballistic tests show an improved aircraft survivability, due in part to the elastomer's mechanical properties and its ability to damp vibrations. New application equipment, system removal, and repair methods are being investigated.

  19. Harbour seals (Phoca vitulina and rehabilitation

    Directory of Open Access Journals (Sweden)

    Nynke Osinga

    2010-09-01

    Full Text Available Throughout the past few decades, rehabilitation of seals has become an activity that is anchored in the present day society of many countries. Seals are primarily rehabilitated to help individual animals in distress. At the same time, the release of seals which would have otherwise died can be considered as a contribution to the population. Most rehabilitated seals are animals under one year of age. They are mainly orphans, weaned seals with complications and seals with a parasiticbronchopneumonia. For the optimal handling of seals and their diseases, centralised operations with quality standards are essential. Rehabilitation provides an instrument to monitor the health of the seal population and its ecosystem. Changes in stranding trends or the appearance of new diseases can be monitored. Moreover, rehabilitation is important to show the general public thestate of the marine environment. In the Netherlands there is significant social support for the rehabilitation of seals. Experience obtained with seal care is of importance in countries where urgent help of threatened seal species is required. Here individual seals are also ambassadors to raise support for the protection of this species in general. Given that the anthropogenic impact on the seals and their environment is extensive in the Wadden Sea, rehabilitation centres can compensate the consequences of this impact on individual seals as well as the population as a whole.

  20. Iodine-125 radioimmunoassay for the direct detection of benzodiazepines in blood and urine

    Energy Technology Data Exchange (ETDEWEB)

    Goddard, C.P.; Stead, A.H.; Mason, P.A.; Law, B.; Moffat, A.C.; McBrien, M.; Cosby, S.

    1986-05-01

    A radioimmunoassay (RIA) for the direct detection of benzodiazepines in blood and urine is described. It is based on a commercially available antiserum and an easily synthesised radio-iodinated derivative of clonazepam that allows the use of relatively simple gamma-counting procedures. The assay can detect low therapeutic levels of all of the benzodiazepines currently available in the UK in 50-..mu..l samples of blood and urine (1-50 ng ml/sup -1/, depending on the drug); no prior sample preparation is required. It is inexpensive, rapid, simple to perform and is broadly specific for the benzodiazepine class of drugs. The assay offers a most suitable means of screening large numbers of samples of forensic interest for the presence of the benzodiazepines.

  1. Serial Intravitreal Bevacizumab Injections Slow the Progression of Radiation Maculopathy Following Iodine-125 Plaque Radiotherapy.

    Science.gov (United States)

    Stacey, Andrew W; Demirci, Hakan

    2016-01-01

    To assess the outcomes of intravitreal bevacizumab injection in the management of radiation maculopathy secondary to plaque radiotherapy, and to identify optimal treatment strategies. A retrospective review of all choroidal melanoma patients at one referral center who were treated with plaque radiotherapy, subsequently developed radiation maculopathy, and received intravitreal bevacizumab. A total of 31 patients were identified. The mean visual acuity decreased three Snellen lines in the year leading up to the first bevacizumab injection. After initiating injection therapy, the mean visual acuity remained stable for 9 months. The change in visual acuity of patients who received injections within 90 days of previous injections was significantly better than the visual acuity of those who received injections more than 90 days apart (p=0.0003). Patients who demonstrated late-phase macular leakage on fluorescein angiography at the time of the first bevacizumab injection had better long-term visual acuity outcomes than patients who had no evidence of macular leakage (average of one line improvement of vision vs. ten line loss of vision, p=0.03). Intravitreal bevacizumab injection was effective in stabilizing visual acuity in patients with radiation maculopathy. Patients benefited most from injections administered every 90 days or sooner. Fluorescein angiography can help identify patients who will respond favorably to treatment.

  2. Preparation of iodine - 125 - labeled insulin for radioimmunoassay: comparison of chloramine T and iodogen iodination

    International Nuclear Information System (INIS)

    Toledo e Souza, I.T. de; Giannella Neto, D.; Wajchenberg, B.L.

    1988-05-01

    Stoichiometric iodination of porcine insulin was performed to the general method of Hunter and Greenwood with modifications recommended by Roth. These method was compared with radioidination using Iodogen. Films of Iodogen react rapidly in the solid phase with aqueous mixtures of I - and proteins. For two methods satisfactory activity of the labeled porcine insulin was obtained and characteristics of the radioimmunoassay were studied. (author) [pt

  3. Interstitial brachytherapy of localised prostate cancer using iodine 125 permanent implants

    International Nuclear Information System (INIS)

    Peiffert, D.

    2005-01-01

    Brachytherapy with permanent implants is a validated method of treatment of prostate adenocarcinomas of favourable prognosis. Its technology is based on endorectal ultrasonography and on per-operative visualisation of the implant and the dose distribution. A strict selection of the patients is necessary before this localised treatment. An active collaboration between urologists, radio-physicists and radiation oncologists is necessary during all the process of selection, treatment and follow-up of the patients. An assessment of the carcinological and functional results is necessary. Recommendations are formalized by a joint collaboration between members of the AFU and of the SFRO. (author)

  4. Ocular Response of Choroidal Melanoma With Monosomy 3 Versus Disomy 3 After Iodine-125 Brachytherapy

    International Nuclear Information System (INIS)

    Marathe, Omkar S.; Wu, Jeffrey; Lee, Steve P.; Yu Fei; Burgess, Barry L.; Leu Min; Straatsma, Bradley R.; McCannel, Tara A.

    2011-01-01

    Purpose: To report the ocular response of choroidal melanoma with monosomy 3 vs. disomy 3 after 125 I brachytherapy. Methods and Materials: We evaluated patients with ciliochoroidal melanoma managed with fine needle aspiration biopsy immediately before plaque application for 125 I brachytherapy between January 1, 2005 and December 31, 2008. Patients with (1) cytopathologic diagnosis of melanoma, (2) melanoma chromosome 3 status identified by fluorescence in situ hybridization, and (3) 6 or more months of follow-up after brachytherapy were sorted by monosomy 3 vs. disomy 3 and compared by Kruskal-Wallis test. Results: Among 40 ciliochoroidal melanomas (40 patients), 15 had monosomy 3 and 25 had disomy 3. Monosomy 3 melanomas had a median greatest basal diameter of 12.00 mm and a median tumor thickness of 6.69 mm before brachytherapy; at a median of 1.75 years after brachytherapy, median thickness was 3.10 mm. Median percentage decrease in tumor thickness was 48.3%. Disomy 3 melanomas had a median greatest basal diameter of 10.00 mm and median tumor thickness of 3.19 mm before brachytherapy; at a median of 2.00 years after brachytherapy, median tumor thickness was 2.37 mm. The median percentage decrease in tumor thickness was 22.7%. Monosomy 3 melanomas were statistically greater in size than disomy 3 melanomas (p < 0.001) and showed a greater decrease in tumor thickness after brachytherapy (p = 0.006). Conclusion: In this study, ciliochoroidal melanomas with monosomy 3 were significantly greater in size than disomy 3 melanoma and showed a significantly greater decrease in thickness at a median of 1.75 years after brachytherapy. The greater decrease in monosomy 3 melanoma thickness after brachytherapy is consistent with other malignancies in which more aggressive pathology has been shown to be associated with a greater initial response to radiotherapy.

  5. Ocular Response of Choroidal Melanoma With Monosomy 3 Versus Disomy 3 After Iodine-125 Brachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    Marathe, Omkar S. [David Geffen School of Medicine, University of Los Angeles, Los Angeles, CA (United States); Wu, Jeffrey; Lee, Steve P. [Department of Radiation Oncology, University of Los Angeles, Los Angeles, CA (United States); Yu Fei; Burgess, Barry L. [Department of Ophthalmology, The Jules Stein Eye Institute, University of Los Angeles, Los Angeles, CA (United States); Leu Min [Department of Radiation Oncology, University of Los Angeles, Los Angeles, CA (United States); Straatsma, Bradley R. [Department of Ophthalmology, The Jules Stein Eye Institute, University of Los Angeles, Los Angeles, CA (United States); McCannel, Tara A., E-mail: TMcCannel@jsei.ucla.edu [Department of Ophthalmology, Jules Stein Eye Institute, University of Los Angeles, Los Angeles, CA (United States); Jonsson Comprehensive Cancer Center, University of Los Angeles, Los Angeles, CA (United States)

    2011-11-15

    Purpose: To report the ocular response of choroidal melanoma with monosomy 3 vs. disomy 3 after {sup 125}I brachytherapy. Methods and Materials: We evaluated patients with ciliochoroidal melanoma managed with fine needle aspiration biopsy immediately before plaque application for {sup 125}I brachytherapy between January 1, 2005 and December 31, 2008. Patients with (1) cytopathologic diagnosis of melanoma, (2) melanoma chromosome 3 status identified by fluorescence in situ hybridization, and (3) 6 or more months of follow-up after brachytherapy were sorted by monosomy 3 vs. disomy 3 and compared by Kruskal-Wallis test. Results: Among 40 ciliochoroidal melanomas (40 patients), 15 had monosomy 3 and 25 had disomy 3. Monosomy 3 melanomas had a median greatest basal diameter of 12.00 mm and a median tumor thickness of 6.69 mm before brachytherapy; at a median of 1.75 years after brachytherapy, median thickness was 3.10 mm. Median percentage decrease in tumor thickness was 48.3%. Disomy 3 melanomas had a median greatest basal diameter of 10.00 mm and median tumor thickness of 3.19 mm before brachytherapy; at a median of 2.00 years after brachytherapy, median tumor thickness was 2.37 mm. The median percentage decrease in tumor thickness was 22.7%. Monosomy 3 melanomas were statistically greater in size than disomy 3 melanomas (p < 0.001) and showed a greater decrease in tumor thickness after brachytherapy (p = 0.006). Conclusion: In this study, ciliochoroidal melanomas with monosomy 3 were significantly greater in size than disomy 3 melanoma and showed a significantly greater decrease in thickness at a median of 1.75 years after brachytherapy. The greater decrease in monosomy 3 melanoma thickness after brachytherapy is consistent with other malignancies in which more aggressive pathology has been shown to be associated with a greater initial response to radiotherapy.

  6. An iodine-125 radioimmunoassay for the direct detection of benzodiazepines in blood and urine

    International Nuclear Information System (INIS)

    Goddard, C.P.; Stead, A.H.; Mason, P.A.; Law, B.; Moffat, A.C.; McBrien, M.; Cosby, S.

    1986-01-01

    A radioimmunoassay (RIA) for the direct detection of benzodiazepines in blood and urine is described. It is based on a commercially available antiserum and an easily synthesised radio-iodinated derivative of clonazepam that allows the use of relatively simple gamma-counting procedures. The assay can detect low therapeutic levels of all of the benzodiazepines currently available in the UK in 50-μl samples of blood and urine (1-50 ng ml -1 , depending on the drug); no prior sample preparation is required. It is inexpensive, rapid, simple to perform and is broadly specific for the benzodiazepine class of drugs. The assay offers a most suitable means of screening large numbers of samples of forensic interest for the presence of the benzodiazepines. (author)

  7. Prostate-Specific Antigen Bounce After Permanent Iodine-125 Prostate Brachytherapy-An Australian Analysis

    International Nuclear Information System (INIS)

    Zwahlen, Daniel R.; Smith, Ryan; Andrianopoulos, Nick; Matheson, Bronwyn; Royce, Peter; Millar, Jeremy L.

    2011-01-01

    Purpose: To report on prostate-specific antigen (PSA) 'bounces' after 125 I prostate brachytherapy to review the relationship to biochemical control and correlate both clinical and dosimetric variables. Methods and Materials: We analyzed 194 hormone-naive patients with a follow-up of ≥3 years. Four bounce definitions were applied: an increase of ≥0.2 ng/mL (definition I), ≥0.4 ng/mL (definition II), ≥15% (definition III), and ≥35% (definition IV) of a previous value with spontaneous return to the prebounce level or lower. Results: Using definition I, II, III, and IV, a bounce was detected in 50%, 34%, 11%, and 9% of patients, respectively. The median time to onset was 14-16 months, the duration was 12-21.5 months, and the magnitude of the increase was 0.5-2 ng/mL. A magnitude of >2 ng/mL, fulfilling the criteria for biochemical failure (BF) according to the American Society for Therapeutic Radiology and Oncology Phoenix definition, was detected in 11.3%, 16.9%, 47.6%, and 50% using definitions I, II, III, and IV, respectively; 11 patients (5.7%) had true BF. The PSA bounces occurred earlier than BF (p < 0.001). The prediction of BF remains controversial and is probably unrelated to biochemical control. The only statistically significant factor predictive of a PSA bounce was younger age (definitions I and II). Conclusion: PSA bounces are common after brachytherapy. All definitions resulted in a high number of false-positive calls for BF during the first 2 years. The definition of an increase of ≥0.2 ng/mL should be preferred because of the lowest number of false-positive results for BF. Patients experiencing a PSA bounce during the first 2 years after brachytherapy should undergo surveillance every 3-6 months. Additional investigations are recommended for elevated postimplant PSA levels that have not corrected by 3 years of follow-up.

  8. Iodine-125 induced DNA strand breakage: Contributions of different physical and chemical radiation action mechanisms

    International Nuclear Information System (INIS)

    Li, W.

    2002-01-01

    The decay of the radioisotope 125 I into 125 Te is typically followed by the emission of two groups of approximately 10 electrons each. In deoxyribonucleic acid (DNA) with 125 I incorporated, these electrons produce various types of damage to DNA, e.g. single and double strand breaks. They occur through direct actions of physical tracks, or indirect actions of radicals produced in water. Among the direct actions one should consider not only the excitation and ionization of DNA by electrons but also the neutralization of highly charged 125m Te ions with electrons from neighboring molecules. The present work begins with a detailed description of electron tracks with the use of the PARTRAC code, compares results with recent experiments, and concludes with a firm assessment of the contribution to the strand break yields from the neutralization effect. (orig.)

  9. Reactions of iodine-125 with gaseous ethene induced via EC-decay of xenon-125

    International Nuclear Information System (INIS)

    Franken, K.; Coenen, H.H.

    1990-01-01

    Decay-induced reactions of nucleogenic iodine species in situ via the 125 Xe(EC) 125 I decay were examined in gaseous ethene. Vinyl iodide is the only monomeric compound found in pure ethene with 0.7% radiochemical yield besides 10% radioiodinated oligomers, which were analyzed by gel permeation chromatography. Addition of rare gases increases the yield of C 2 H 3 I up to 3.3% and of oligomers to about 25%. The effect of different rare gasese indicates substitution reactions of thermal iodine cations in 1 D 2 and 1 S 2 excited states with a 25% and in the 2 P 1 and 2 P 0 states with 75% contribution. Endothermic and homolytic reactions could be excluded for vinyl iodide generation. Radical besides ionic induced oligomerization, however, seem to occur since traces of oxygen increase the organic product yields. The chain length of oligomers formed is strongly reduced in the presence of rare gases, oxygen and especially of H-acidic compounds (HX, X = OH, OCH 3 , OC 2 H 5 ). Latter additives were also effective in trapping the intermediately formed ethene-iodonium complex giving rise to 1-iodo-2-X-ethanes. In presence of 1% HCl the production of 125 ICH 2 CH 2 Cl proceeded with preparative radiochemical yields of up to 70%. This occurs by primary formation of 125 ICl and subsequent addition to ethene. (orig.)

  10. Turbine interstage seal with self-balancing capability

    Energy Technology Data Exchange (ETDEWEB)

    Mills, Jacob A; Jones, Russell B; Sexton, Thomas D

    2017-09-26

    An interstage seal for a turbine of a gas turbine engine, the interstage seal having a seal carrier with an axial extending seal tooth movable with a stator of the engine, and a rotor with a seal surface that forms the interstage seal with the seal tooth, where a magnetic force produced by two magnets and a gas force produced by a gas pressure acting on the seal carrier forms a balancing force to maintain a close clearance of the seal without the seal tooth contacting the rotor seal surfaces during engine operation. In other embodiments, two pairs of magnets produce first and second magnetic forces that balance the seal in the engine.

  11. Monolithic LTCC seal frame and lid

    Energy Technology Data Exchange (ETDEWEB)

    Krueger, Daniel S.; Peterson, Kenneth A.; Stockdale, Dave; Duncan, James Brent; Riggs, Bristen

    2016-06-21

    A method for forming a monolithic seal frame and lid for use with a substrate and electronic circuitry comprises the steps of forming a mandrel from a ceramic and glass based material, forming a seal frame and lid block from a ceramic and glass based material, creating a seal frame and lid by forming a compartment and a plurality of sidewalls in the seal frame and lid block, placing the seal frame and lid on the mandrel such that the mandrel fits within the compartment, and cofiring the seal frame and lid block.

  12. EBR-II rotating plug seal maintenance

    International Nuclear Information System (INIS)

    Allen, K.J.

    1986-01-01

    The EBR-II rotating plug seals require frequent cleaning and maintenance to keep the plugs from sticking during fuel handling. Time consuming cleaning on the cover gas and air sides of the dip ring seal is required to remove oxidation and sodium reaction products that accumulate and stop plug rotation. Despite severely limited access, effective seal cleaning techniques have removed 11 800 lb (5 352 kg) of deposits from the seals since 1964. Temperature control modifications and repairs have also required major maintenance work. Suggested seal design recommendations could significantly reduce maintenance on future similar seals

  13. Mechanical seal with textured sidewall

    Energy Technology Data Exchange (ETDEWEB)

    Khonsari, Michael M.; Xiao, Nian

    2017-02-14

    The present invention discloses a mating ring, a primary ring, and associated mechanical seal having superior heat transfer and wear characteristics. According to an exemplary embodiment of the present invention, one or more dimples are formed onto the cylindrical outer surface of a mating ring sidewall and/or a primary ring sidewall. A stationary mating ring for a mechanical seal assembly is disclosed. Such a mating ring comprises an annular body having a central axis and a sealing face, wherein a plurality of dimples are formed into the outer circumferential surface of the annular body such that the exposed circumferential surface area of the annular body is increased. The texture added to the sidewall of the mating ring yields superior heat transfer and wear characteristics.

  14. Secondary seal effects in hydrostatic non-contact seals for reactor coolant pump shaft

    International Nuclear Information System (INIS)

    Fujita, T.; Koga, T.; Tanoue, H.; Hirabayashi, H.

    1987-01-01

    The paper presents a seal flow analysis in a hydrostatic non-contact seal for a PWR coolant pump shaft. A description is given of the non-contact seal for the reactor coolant pump. Results are presented for a distortion analysis of the seal ring, along with the seal flow characteristics and the contact pressure profiles of the secondary seals. The results of the work confirm previously reported findings that the seal ring distortion is sensitive to the o-ring location (which was placed between the ceramic seal face and the seal ring retainer). The paper concludes that the seal flow characteristics and the tracking performance depend upon the dynamic properties of the secondary seal. (U.K.)

  15. Sealed source peer review plan

    International Nuclear Information System (INIS)

    Feldman, Alexander; Leonard, Lee; Burns, Ron

    2009-01-01

    Sealed sources are known quantities of radioactive materials that have been encapsulated in quantities that produce known radiation fields. Sealed sources have multiple uses ranging from instrument calibration sources to sources that produce radiation fields for experimental applications. The Off-Site Source Recovery (OSR) Project at Los Alamos National Laboratory (LANL), created in 1999, under the direction of the Waste Management Division of the U.S. Department of Energy (DOE) Albuquerque has been assigned the responsibility to recover and manage excess and unwanted radioactive sealed sources from the public and private sector. LANL intends to ship drums containing qualified sealed sources to the Waste Isolation Pilot Plant (WIPP) for disposal. Prior to shipping, these drums must be characterized with respect to radiological content and other parameters. The U. S. Environmental Protection Agency (EPA) requires that ten radionulcides be quantified and reported for every container of waste to be disposed in the WIPP. The methods traditionally approved by the EPA include non-destructive assay (NDA) in accordance with Appendix A of the Contact-Handled Transuranic Waste Acceptance Criteria for the Waste Isolation Pilot Plant (DOE, 2002) (CH WAC). However, because of the nature and pedigree of historical records for sealed sources and the technical infeasibility of performing NDA on these sources, LANL proposes to characterize the content of these waste drums using qualified existing radiological data in lieu of direct measurement. This plan describes the process and documentation requirements for the use of the peer review process to qualify existing data for sealed radiological sources in lieu of perfonning radioassay. The peer review process will be performed in accordance with criteria provided in 40 CFR (section) 194.22 which specifies the use of the NUREG 1297 guidelines. The plan defines the management approach, resources, schedule, and technical requirements

  16. Stabilizing geometry for hydrodynamic rotary seals

    Science.gov (United States)

    Dietle, Lannie L.; Schroeder, John E.

    2010-08-10

    A hydrodynamic sealing assembly including a first component having first and second walls and a peripheral wall defining a seal groove, a second component having a rotatable surface relative to said first component, and a hydrodynamic seal comprising a seal body of generally ring-shaped configuration having a circumference. The seal body includes hydrodynamic and static sealing lips each having a cross-sectional area that substantially vary in time with each other about the circumference. In an uninstalled condition, the seal body has a length defined between first and second seal body ends which varies in time with the hydrodynamic sealing lip cross-sectional area. The first and second ends generally face the first and second walls, respectively. In the uninstalled condition, the first end is angulated relative to the first wall and the second end is angulated relative to the second wall. The seal body has a twist-limiting surface adjacent the static sealing lip. In the uninstalled condition, the twist-limiting surface is angulated relative to the peripheral wall and varies along the circumference. A seal body discontinuity and a first component discontinuity mate to prevent rotation of the seal body relative to the first component.

  17. Self-Sealing Cryogenic Fitting

    Science.gov (United States)

    Jia, Lin Xiang; Chow, Wen Lung; Moslemian, Davood; Lin, Gary; Melton, Greg

    1994-01-01

    Self-sealing fitting for cryogenic tubes remains free of leakage from room temperature to liquid-helium temperature even at internal pressure as high as 2.7 MPa. Fitting comprises parts made of materials with different coefficients of thermal expansion to prevent leakage gaps from forming as temperature decreases. Consists of coupling nut, two flared tube ends, and flared O-ring spacer. Spacer contracts more than tube ends do as temperature decreases. This greater contraction seals tube ends more tightly, preventing leakage.

  18. Seals in motion. How movements drive population development of harbour seals and grey seals in the North Sea

    OpenAIRE

    Brasseur, S.M.J.M.

    2017-01-01

    The harbour seal Phoca vitulina and the grey seal Halichoerus grypus have been inhabitants of the Wadden Sea since millennia. Prehistoric findings indicate the presence of both species around 5000 BC. This changed dramatically in the mid Middle-Ages as around 1500 AC, the grey seal disappeared from the Wadden Sea as a consequence of persecution. With growing hunting pressure, especially in the 20th century and concurrent habitat destruction and pollution, the harbour seals reached all time lo...

  19. influence of treatment of seed potato tubers with plant crude

    African Journals Online (AJOL)

    ACSS

    Seed potato tuber treatment with plant crude essential oil extracts. 297 were pipetted on to filter paper (Whatman No. 9;. 18.5 cm diameter; Whatman, Maidstone, Kent,. Germany), which was taped inside of the lid of each plastic, at the pre-determined treatment doses. The jars were lid-sealed and arranged in a completely ...

  20. Apollo Seals: A Basis for the Crew Exploration Vehicle Seals

    Science.gov (United States)

    Finkbeiner, Joshua R.; Dunlap, Patrick H., Jr.; Steinetz, Bruce M.; Daniels, Christopher C.

    2007-01-01

    NASA s Vision for Space Exploration Replace the Space Shuttle for missions to ISS. Return to the Moon. Allow manned exploration of Mars. Apollo-like configuration. Blunt-body heat shield. Conical backshell. CEV requires seal development. Prevent ingestion of reentry gases. Prevent loss of habitable atmosphere.

  1. HMSRP Hawaiian Monk Seal Handling Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains records for all handling and measurement of Hawaiian monk seals since 1981. Live seals are handled and measured during a variety of events...

  2. Film riding seals for rotary machines

    Science.gov (United States)

    Bidkar, Rahul Anil; Sarawate, Neelesh Nandkumar; Wolfe, Christopher Edward; Ruggiero, Eric John; Raj Mohan, Vivek Raja

    2017-03-07

    A seal assembly for a rotary machine is provided. The seal assembly includes multiple sealing device segments disposed circumferentially intermediate to a stationary housing and a rotor. Each of the segments includes a shoe plate with a forward-shoe section and an aft-shoe section having one or more labyrinth teeth therebetween facing the rotor. The sealing device includes a stator interface element having a groove or slot for allowing disposal of a spline seal for preventing segment leakages. The sealing device segment also includes multiple bellow springs or flexures connected to the shoe plate and to the stator interface element. Further, the sealing device segments include a secondary seal integrated with the stator interface element at one end and positioned about the multiple bellow springs or flexures and the shoe plate at the other end.

  3. Legacy HMSRP Hawaiian Monk Seals Observers

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set documents observers that have collected monk seal data as part of the ongoing monk seal population assessment efforts by PSD personnel and cooperating...

  4. Dynamic analysis of noncontacting hydrostatic seals

    International Nuclear Information System (INIS)

    Kokarakis, J.E.; Thomas, J.M.

    1988-01-01

    A troublesome operating history for hydrostatic seals in reactor coolant pumps motivates an investigation of the dynamics of a typical seal system. A dynamic model of the seal ring is formulated and the response of the seal to transient and steady excitation is analyzed. The model is capable of treating response of the seal ring to excitation by both pressure fluctuations at the faceplate and/or axial motion of the shaft. It also includes the effects of friction between the secondary seal and the mating insert. Damping, inherent in the fluid film between the seal faceplates, is considered by including dynamic pressure variations due to squeeze. A typical hydrostatic seal is analyzed in the numerical applications to study the interrelation between the design parameters, the stability of the system, and the potential contact between the stationery and rotating faces

  5. HMSRP Hawaiian Monk Seal Entanglement data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The data set contains records of all entanglements of Hawaiian monk seals in marine debris. The data set comprises records of seals entangled by derelict fishing...

  6. HMSRP Hawaiian Monk Seal Telemetry Tag Deployments

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This project investigates foraging behavior of Hawaiian monk seals by conducting telemetry studies. During these studies, live seals are instrumented with dive...

  7. Legacy HMSRP Hawaiian Monk Seal Ultrasound Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Ultrasound images for measuring the condition of juvenile seals at Laysan Island during 2009-2010, collected when seals were handled as part of the De-Worming Project

  8. HMSRP Hawaiian Monk Seal Crittercam video

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This project investigates foraging behavior of Hawaiian monk seals by conducting telemetry studies. During these studies, live seals are instrumented with dive...

  9. HMSRP Hawaiian Monk Seal Argos Location Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This project investigates foraging behavior of Hawaiian monk seals by conducting telemetry studies. During these studies, live seals are instrumented with satellite...

  10. Seal Apparatus and Methods to Manufacture Thereof

    Science.gov (United States)

    Richard, James A. (Inventor)

    2013-01-01

    In some implementations, apparatus and methods are provided through which a dynamic cryogenic seal is manufactured. In some implementations, the seal includes a retainer and a spring-seal assembly, the assembly being comprised of a main spring housing and fluorine-containing polymer seals. In some implementations, either a radial seal, or an axial (or "piston seal") is provided. In some implementations, methods of manufacturing the dynamic cryogenic seal are also provided. In some implementations, the methods include assembling the components while either heated or cooled, taking advantage of thermal expansion and contraction, such that there is a strong interference fit between the components at room temperature. In some implementations, this process ensures that the weaker fluorine-containing polymer seal is forced to expand and contract with the stronger retainer and spring and is under constant preload. In some implementations, the fluorine-containing polymer is therefore fluidized and retained, and can not lift off.

  11. Overview of LIDS Docking Seals Development

    Science.gov (United States)

    Dunlap, Patrick; Steinetz, Bruce; Daniels, Christopher

    2009-01-01

    GRC is supporting JSC by developing LIDS main interface seals Seal development and testing is occurring at both sub-scale and full-scale levels: a) Small-scale tests performed to define seal materials and evaluate exposure to space environments. b) Medium-scale testing: 1) Permits evaluation of candidate seal designs at faster pace than for full-scale seals. 2) Leak rates and loads can be scaled up to full-scale for indication of seal performance. c) Full-scale test rigs used for seal development and flight qualification tests and to assess on-orbit anomalies if needed. GRC responsible for delivering flight hardware seals to JSC approx.2013 for integration into LIDS flight units.

  12. Non Destructive Seal Testing Polymeric Tray

    Science.gov (United States)

    2006-10-01

    School of Enviromental and Biological Science Rutgers, The State University of New Jersey New Brunswick, New Jersey 08903 Principal Investigator...strength, tack seals and seal creep. The following modifications were issued : Jan 20, 2004 0008/01 Add incremental funding to increase total...Technologies”. Most of the “commercial off the shelf” systems are designed to detect seal integrity issues , such as seal contamination, cuts and holes. A

  13. Reactor coolant pump seals: improving their performance

    International Nuclear Information System (INIS)

    Pothier, N.E.; Metcalfe, R.

    1986-06-01

    Large CANDU plants are benefitting from transient-resistant four-year reliable reactor coolant pump seal lifetimes, a direct result of AECL's 20-year comprehensive seal improvement program involving R and D staff, manufacturers, and plant designers and operators. An overview of this program is presented, which covers seal modification design, testing, post-service examination, specialized maintenance and quality control. The relevancy of this technology to Light Water Reactor Coolant Pump Seals is also discussed

  14. Development of simplified rotating plug seal structure

    International Nuclear Information System (INIS)

    Ueta, M.; Ichimiya, M.; Kanaoka, T.; Sekiya, H.; Ueda, S.; Ishibashi, S.

    1991-01-01

    We studied a compact and simplified rotating plug seal structure and conducted experiments for key elements of the concept such us the mechanical seal structure and sodium deposit prevention system. Good characteristics were confirmed for the mechanical seal structure, which utilizes an elastomer seal and thin lathe bearing. Applicability of the density barrier concept was also confirmed as the sodium deposit prevention system. This concept can be applied to actual plants. (author)

  15. Acoustic resonance spectroscopy intrinsic seals

    International Nuclear Information System (INIS)

    Olinger, C.T.; Burr, T.; Vnuk, D.R.

    1994-01-01

    We have begun to quantify the ability of acoustic resonance spectroscopy (ARS) to detect the removal and replacement of the lid of a simulated special nuclear materials drum. Conceptually, the acoustic spectrum of a container establishcs a baseline fingerprint, which we refer to as an intrinsic seal, for the container. Simply removing and replacing the lid changes some of the resonant frequencies because it is impossible to exactly duplicate all of the stress patterns between the lid and container. Preliminary qualitative results suggested that the ARS intrinsic seal could discriminate between cases where a lid has or has not been removed. The present work is directed at quantifying the utility of the ARS intrinsic seal technique, including the technique's sensitivity to ''nuisance'' effects, such as temperature swings, movement of the container, and placement of the transducers. These early quantitative tests support the potential of the ARS intrinsic seal application, but also reveal a possible sensitivity to nuisance effects that could limit environments or conditions under which the technique is effective

  16. Ergonomics and safety of manual bag sealing.

    NARCIS (Netherlands)

    Groot, M.D. de; Bosch, T.; Eikhout, S.M.; Vink, P.

    2005-01-01

    A variety of seals is used to close bags. Each seal has advantages and disadvantages. For shop assistants sealing bags could be a repetitive physically demanding action. Opening and closing the bags again can cause some discomfort or annoyance for consumers. Besides, it is an activity which can

  17. Annular Pressure Seals and Hydrostatic Bearings

    National Research Council Canada - National Science Library

    San Andres, Luis

    2006-01-01

    ..., in particular those handling large density fluids. Highlights on the bulk-flow analysis of annular seals are given with details on the performance of two water seals long and short, featuring the advantages of an anti-swirl brake to enhance the seal...

  18. 19 CFR 113.25 - Seals.

    Science.gov (United States)

    2010-04-01

    ... signatures of principal and surety, if individuals, and the corporate seal shall be affixed close to the... law of the state in which executed. However, when the charter or governing statute of a corporation requires its acts to be evidenced by its corporate seal, such seal is required. ...

  19. 36 CFR 901.6 - Seal.

    Science.gov (United States)

    2010-07-01

    ... 36 Parks, Forests, and Public Property 3 2010-07-01 2010-07-01 false Seal. 901.6 Section 901.6 Parks, Forests, and Public Property PENNSYLVANIA AVENUE DEVELOPMENT CORPORATION BYLAWS OF THE CORPORATION § 901.6 Seal. The Corporation may adopt a corporate seal which shall have the name of the...

  20. Piston rod seal for a Stirling engine

    Science.gov (United States)

    Shapiro, Wilbur

    1984-01-01

    In a piston rod seal for a Stirling engine, a hydrostatic bearing and differential pressure regulating valve are utilized to provide for a low pressure differential across a rubbing seal between the hydrogen and oil so as to reduce wear on the seal.

  1. Aerodynamic seal assemblies for turbo-machinery

    Science.gov (United States)

    Bidkar, Rahul Anil; Wolfe, Christopher; Fang, Biao

    2015-09-29

    The present application provides an aerodynamic seal assembly for use with a turbo-machine. The aerodynamic seal assembly may include a number of springs, a shoe connected to the springs, and a secondary seal positioned about the springs and the shoe.

  2. Tribological Tuft Testing Candidate Brush Seal Materials

    Science.gov (United States)

    DellaCorte, Chris

    1999-01-01

    This paper presents a tribological tuft test method of candidate brush seal materials in viewgraph form. The goals of the research are: 1) To develop test method to tribologically brush seal materials; 2) To evaluate materials to identify potential improvements and trends; and 3) Guide seal material development and selection.

  3. Improved sealing for in-core systems

    International Nuclear Information System (INIS)

    Dunford, S.

    1989-01-01

    The in-core instrumentation sealing nozzles designed by Framatome have three mechanical seals in series instead of the one traditional seal, and are pressurized by simply tightening up the nozzle covers. They have been installed from the start on all Framatome PWRs, as well as having been backfitted on Belgium and Yugoslavian units and chosen for the Chinese Qinshan plant. (author)

  4. Dampers for Stationary Labyrinth Seals

    Science.gov (United States)

    El-Aini, Yehia; Mitchell, William; Roberts, Lawrence; Montgomery, Stuart; Davis, Gary

    2011-01-01

    Vibration dampers have been invented that are incorporated as components within the stationary labyrinth seal assembly. These dampers are intended to supplement other vibration-suppressing features of labyrinth seals in order to reduce the incidence of high-cycle-fatigue failures, which have been known to occur in the severe vibratory environments of jet engines and turbopumps in which labyrinth seals are typically used. A vibration damper of this type includes several leaf springs and/or a number of metallic particles (shot) all held in an annular seal cavity by a retaining ring. The leaf springs are made of a spring steel alloy chosen, in conjunction with design parameters, to maintain sufficient preload to ensure effectiveness of damping at desired operating temperatures. The cavity is vented via a small radial gap between the retaining ring and seal housing. The damping mechanism is complex. In the case of leaf springs, the mechanism is mainly friction in the slippage between the seal housing and individual dampers. In the case of a damper that contains shot, the damping mechanism includes contributions from friction between individual particles, friction between particles and cavity walls, and dissipation of kinetic energy of impact. The basic concept of particle/shot vibration dampers has been published previously; what is new here is the use of such dampers to suppress traveling-wave vibrations in labyrinth seals. Damping effectiveness depends on many parameters, including, but not limited to, coefficient of friction, mode shape, and frequency and amplitude of vibrational modes. In tests, preloads of the order of 6 to 15 lb (2.72 to 6.8 kilograms) per spring damper were demonstrated to provide adequate damping levels. Effectiveness of shot damping of vibrations having amplitudes from 20 to 200 times normal terrestrial gravitational acceleration (196 to 1,960 meters per square second) and frequencies up to 12 kHz was demonstrated for shot sizes from 0.032 to

  5. Comparative study on two different seal surface structure for reactor pressure vessel sealing behavior

    International Nuclear Information System (INIS)

    Chen Jun; Xiong Guangming; Deng Xiaoyun

    2014-01-01

    The seal surface structure is very important to reactor pressure vessel (RPV) sealing behavior. In this paper, two 3-D RPV sealing analysis finite models have been established with different seal surface structures, in order to study the influence of two structures. The separation of RPV upper and lower flanges, bolt loads and etc. are obtained, which are used to evaluate the sealing behavior of the RPV. Meanwhile, the comparative analysis of safety margin of two seal surface structural had been done, which provides the theoretical basis for RPV seal structure design optimization. (authors)

  6. Immobilisation of southern elephant seals and leopard seals with cyclohexamine anaesthetics and xylazine.

    Science.gov (United States)

    Mitchell, P J; Burton, H R

    1991-10-12

    Ketamine and xylazine were given to 55 southern elephant seals (Mirounga leonina) for stomach lavaging, and to three leopard seals (Hydrurga leptonyx). The elephant seals showed prolonged apnoea and two of them died owing to aspiration of stomach contents. Two of the leopard seals died from unknown causes. Tiletamine and zolazepam were given to five elephant seals and one leopard seal. Two of the elephant seals and the leopard seal died from unknown causes. Xylazine alone was administered to 34 leopard seals. Sedation was poor at low dose rates (less than 1.7 mg/kg) but four of the seals given higher dose rates died owing to the aspiration of stomach contents.

  7. Seed lipids.

    Science.gov (United States)

    Wolff, I A

    1966-12-02

    Many of the newly discovered seedoil acids have reactive or unusual functional groups or other facets of molecular structure that permit their ready differentiation from oleic, linoleic, linolenic, and the other most prevalent saturated and unsaturated long-chain fatty acids. The recognition and availability of the new acids, coupled with methods that make detection and determination easy, will help studies of lipid biosynthesis in the plant and of lipid metabolism and utilization in animals, and will stimulate more studies in depth on the fine points of seedlipid structure. Correlations of structural patterns in seed lipids of particular groups of plants with classical taxonomic categories will permit clarifications, raise needed questions concerning classifications, and accelerate research in chemotaxonomy and phylogenetics. Seed lipids are particularly well suited for establishing relationships among plants because of their great variety in structure compared to the more limited structural types of amino acids, sugars, purines, and many other plant substances. The newly characterized seed oils are potentially important industrial raw materials whenever they come from agronomically promising plant species. The molecular structures of seed triglycerides have major influence on their physical properties and therefore advances in knowledge in that sphere have practical implications. For example, the unusual characteristics of cocoa butter that make it so valuable for food and confectionery use are attributed to the specific arrangement of fatty acids it its triglycerides. The glycerides are almost all 2-oleic-1,3-disaturated acid triglycerides. The physical characteristics of lard are advantageously changed by catalytically rearranging fatty acyl groups among the glycerides initially in the fat to achieve a more nearly random distribution, followed sometimes by further fractionation to remove more saturated glycerides. Through this change of glyceride structures a

  8. Organic leek seed production - securing seed quality

    DEFF Research Database (Denmark)

    Deleuran, Lise Christina; Boelt, Birte

    2011-01-01

    seeds. Tunnel production is a means of securing seed of high genetic purity and quality, and organic leek (Allium porrum L.) seed production was tested in tunnels in Denmark. The present trial focused on steckling size and in all years large stecklings had a positive effect on both seed yield...

  9. Postoperative [{sup 125}I] seed brachytherapy in the treatment of acinic cell carcinoma of the parotid gland. With associated risk factors

    Energy Technology Data Exchange (ETDEWEB)

    Mao, Ming-hui; Zhang, Jian-Guo; Zhang, Jie; Zheng, Lei; Liu, Shu-ming; Huang, Ming-wei; Shi, Yan [Peking Univ. School and Hospital of Stomatology, Beijing (China). Dept. of Oral and Maxillofacial Surgery

    2014-11-15

    This retrospective study was undertaken to analyze data from patients receiving iodine-125 ([{sup 125}I]) seed brachytherapy postoperatively for the treatment of acinic cell carcinoma (ACC) of the parotid gland along with the following risk factors: residual tumor, recurrent tumor, facial nerve invasion, positive resection margins, advanced tumor stage, or tumor spillage. Twenty-nine patients with ACC (17 females, 12 males; age range, 13-73 years; median age, 37.3 years) were included. Median follow-up was 58.2 months (range, 14-122 months). Patients received [{sup 125}I] seed brachytherapy (median actuarial D90, 177 Gy) 3-41 days (median, 14 days) following surgery. Radioactivity was 18.5-33.3 MBq per seed, and the prescription dose was 80-120 Gy. The 3-, 5-, and 10-year rates of local control were 93.1, 88.7, and 88.7 %, respectively; overall survival was 96.6, 92, and 92 %; disease-free survival was 93.1, 88.4, and 88.4 %; and freedom from distant metastasis was 96.6, 91.2, and 91.2 %. Lymph node metastases were absent in all patients, although two patients died with distant metastases. Facial nerve recovery was quick, and no severe radiotherapy-related complications were noted. Recurrence history, local recurrence, and distant metastasis significantly affected overall survival. Postoperative [{sup 125}I] seed brachytherapy is effective in treating ACC and has minor complications. Patients with a history of recurrence showed poor prognosis and were more likely to experience disease recurrence and develop metastases. (orig.) [German] Diese retrospektive Studie wurde durchgefuehrt, um die Daten von Patienten zu analysieren, die postoperativ eine Seed-Brachytherapie mit Iod-125 ([{sup 125}I]) zur Behandlung von Azinuszellkarzinomen der Ohrspeicheldruese mit begleitenden Risikofaktoren, wie Residualtumor, Rezidivtumor, Invasion in den N. facialis, positive (= nicht tumorfreie) Resektionsraender, fortgeschrittenes Tumorstadium oder lokale Verbreitung von Tumorzellen

  10. seed oil

    African Journals Online (AJOL)

    Wara

    found to be 2.0 cm which is lower than that of Jatropha oil soap(5.4cm), Sesame oil soap(4.8cm), Cotton seed oil soap(4.5cm) and shea nut soap(4.2cm),t higher than that of Castor oil soap(1.6cm) and Castor glycerine soap(1.4cm). The soap was milk in colour and slightly soluble in distilled water. Keywords: Neem oil ...

  11. Development of the seal for nuclear material

    International Nuclear Information System (INIS)

    Lu Feng; Lu Zhao; Zhao Yonggang; Zhang Qixin; Xiao Xuefu

    2000-01-01

    Two kinds of double cap metallic seal and an adhesive seal are developed for the purpose of the accounting for and control of nuclear material. Two kinds of double cap metallic seal are made of stainless steel and copper, respectively and the self-locked technique is used. The number and the random pattern are carved out side and in side of a cap, respectively, for the seal. The random pattern carved inside of a cap for seal is taken a picture using numeral camera and memorized in computer. Special software is developed for verification of the random pattern memorized in computer. The adhesive seal is made of special adhesive paper for purpose of security, and a special pattern guarded against falsification is printed on seal paper using ultraviolet fluorescent light technique

  12. Air riding seal with purge cavity

    Science.gov (United States)

    Sexton, Thomas D; Mills, Jacob A

    2017-08-15

    An air riding seal for a turbine in a gas turbine engine, where an annular piston is axial moveable within an annular piston chamber formed in a stator of the turbine and forms a seal with a surface on the rotor using pressurized air that forms a cushion in a pocket of the annular piston. A purge cavity is formed on the annular piston and is connected to a purge hole that extends through the annular piston to a lower pressure region around the annular piston or through the rotor to an opposite side. The annular piston is sealed also with inner and outer seals that can be a labyrinth seal to form an additional seal than the cushion of air in the pocket to prevent the face of the air riding seal from overheating.

  13. Sealing system for a nuclear reactor

    International Nuclear Information System (INIS)

    McEdwards, J.A.

    1982-01-01

    A nuclear reactor is described which is cooled with a liquid metal and, in particular, the seal for such a nuclear reactor is described. The nuclear reactor includes a vessel, which is closed at the top by a top closure. The top closure consists of a least two components, one of which can rotate. There is an annular gap between the two components. The sealing system in the annular gap consists of at least a first and a second seal which can expand, which are situated in series in the top part of the annular gap. The system also includes an immersed seal: this is arranged in a body made of insulating material. The insulating material body is situated on the underside of the top closure. The immersed seal includes a trough at the lower end of one of the components and a sealing edge, which hangs from the other component and extends downwards into the trough. There is a liquid metal bath in the trough, into which part of the sealing edge projects. The sealing edge has at least one opening above the liquid metal bath. This permits a flow connection between the two spaces on the two sides of the sealing edge, i.e. the space between the immersed seal and the expanding seals on the one hand and the protective gas space within the vessel on the other hand. Further, there is a device by which flushing gas can be introduced into the annular gap between the expanding seals and the sealing edge. The flushing gas is provided to a sufficient extent, so that diffusion of radiaoctive protective gas and sodium vapour upwards to the expanding seals is considerably reduced. The flushing gas mixes with the protective gas in the reactor vessel and can be tapped off there, whereupon it is reprocessed and returned to the vessel. (orig.) [de

  14. Seal dynamics on the Swedish west coast: Scenarios of competition as Baltic grey seal intrude on harbour seal territory

    Science.gov (United States)

    Svensson, Carl Johan

    2012-07-01

    The Kattegat-Skagerrak region on the Swedish west coast is home to an abundant harbour seal population (Phoca vitulina) and a small scattered grey seal population (Halichoerus grypus). In addition, grey seal from the growing population in the Baltic Sea frequently migrate into the Kattegat-Skagerrak. Harbour seals on the west coast of Sweden show relatively high population growth (approximately 9%) compared to the Baltic grey seal in ice-free habitats (approximately 6%), which, in theory, makes harbour seal the stronger competitor of the two in this region. However, incidents of disease in harbour seals that lower population growth are becoming more frequent. These epidemics are primarily caused by the Phocine Distemper Virus (PDV), and may reduce population size with up to 70%. This study models the average development under potential scenarios of competing harbour- and Baltic grey seal populations using Leslie matrices and the Lotka-Volterra model of inter-specific competition. The model is parameterised with previously published data, and resource overlap is incorporated through density dependent pup survival. Using numerical methods short- and long-term abundances are simulated under weak, moderate and strong competition and for different frequencies of PDV epidemics. Results show that the harbour seals are resilient to competition while exerting a negative effect on grey seal abundance under moderate to strong competition. Hence Baltic grey seal benefit from weaker levels of competition. Under moderate and strong competition grey seal abundance is a direct function of the PDV frequency as this reduces the competitive strength of harbour seals. Theoretically this means that higher frequencies of PDV or other pathogens epidemics could facilitate an expansion of Baltic grey seal into Kattegat-Skagerrak. Independent of interaction strength and frequency of epidemics the projected changes to abundances are slow (50-100 years), and even in exceedingly stable

  15. Dosimetric studies, spectrometric, radiographic, metallographic of a new argentinean seed of 125 I used in brachytherapy

    International Nuclear Information System (INIS)

    Pirchio, R.; Saravi, M.; Banchik, D.; Munoz, C.

    2006-01-01

    A new source of 125 I model Braquibac TM has been developed in Argentina for applications in interstitial brachytherapy. The AAPM Task Group 43 (TG-43) recommends that dosimetric characteristics of new sources of brachytherapy of Iodine-125 have been theoretically and experimentally determined before its clinical use. The objectives outlined in this work were the study of the design of the new seed, the calculation of dosimetric parameters and the photons spectra analysis. Its were carried out radiographic and metallographic studies to determine the physical characteristics of the source. For the realization of the dosimetric calculations it was used the Monte Carlo code MCNP5. Values of the radial dose function, g(r), of the constant of dose rate, Λ, of the function of anisotropy of two dimensions, F(r, θ), of the factor and constant of anisotropy its were obtained simulating the source in water according to the recommended methodology in TG-43. The constant of dose rate is similar to 0,880 ± 0,080 c Gy h -1 U -1 . The kerma in air rate of reference, S K , was calculated as 1,036 c Gy cm 2 h -1 mCi -1 simulating the seed in dry air. Its were carried out spectrometric studies using a semiconductor planar detector of HPGe (high purity germanium). Photons spectra showed characteristic x-rays of 125 I with energies of 27,20 keV, 27,47 keV, 31 keV and 31,70 keV gamma photons of 35,5 keV, and x-ray fluorescent coming from the silver nucleus of 22,10 keV, 24,94 keV and 25,45 keV. The angular dependence of the intensity of photons around the seed and in air it was analyzed with the planar detector. This was carried out to study the anisotropy in the photons flow due to variation in the thickness of the titanium wall and of the welding, movements of the silver tube inside the source and deposition of the radioactive material on the silver tube. (Author)

  16. Evaluation of dose-volume histograms after prostate seed implantation. 4-year experience

    International Nuclear Information System (INIS)

    Hoinkis, C.; Lehmann, D.; Winkler, C.; Herrmann, T.; Hakenberg, O.W.; Wirth, M.P.

    2004-01-01

    Background and purpose: permanent interstitial brachytherapy by seed implantation is a treatment alternative for low-volume low-risk prostate cancer and a complex interdisciplinary treatment with a learning curve. Dose-volume histograms are used to assess postimplant quality. The authors evaluated their learning curve based on dose-volume histograms and analyzed factors influencing implantation quality. Patients and methods: since 1999, 38 patients with a minimum follow-up of 6 months were treated at the authors' institution with seed implantation using palladium-103 or iodine-125, initially using the preplan method and later real-time planning. Postimplant CT was performed after 4 weeks. The dose-volume indices D90, V100, V150, the D max of pre- and postplans, and the size and position of the volume receiving the prescribed dose (high-dose volume) of the postplans were evaluated. In six patients, postplan imaging both by CT and MRI was used and prostate volumes were compared with preimplant transrectal ultrasound volumes. The first five patients were treated under external supervision. Results: patients were divided into three consecutive groups for analysis of the learning curve (group 1: n = 5 patients treated under external supervision; group 2: n = 13 patients; group 3: n = 20 patients). D90 post for the three groups were 79.3%, 74.2%, and 99.9%, the V100 post were 78.6%, 73.5%, and 88.2%, respectively. The relationship between high-dose volume and prostate volume showed a similar increase as the D90, while the relationship between high-dose volume lying outside the prostate and prostate volume remained constant. The ratio between prostate volumes from transrectal ultrasound and CT imaging decreased with increasing D90 post , while the preplanning D90 and V100 remained constant. The different isotopes used, the method of planning, and the implanted activity per prostate volume did not influence results. Conclusion: a learning curve characterized by an increase

  17. Core disruptive accident margin seal

    International Nuclear Information System (INIS)

    Garin, J.; Belsick, J.C.

    1978-01-01

    Disclosed is an apparatus for sealing the annulus defined between a substantially cylindrical rotatable first riser assembly and plug combination disposed in a substantially cylindrical second riser assembly and plug combination of a nuclear reactor system. The apparatus comprises a flexible member disposed between the first and second riser components and attached to a metal member which is attached to an actuating mechanism. When the actuating mechanism is not actuated, the flexible member does not contact the riser components thus allowing the free rotation of the riser components. When desired, the actuating mechanism causes the flexible member to contact the first and second riser components in a manner to block the annulus defined between the riser components, thereby sealing the annulus between the riser components

  18. Transport of multiassembly sealed canisters

    International Nuclear Information System (INIS)

    Quinn, R.D.; Lehnert, R.A.; Rosa, J.M.

    1992-01-01

    A significant portion of the commercial spent nuclear fuel in dry storage in the US will be stored in multiassembly sealed canisters before the DOE begins accepting fuel from utilities in 1998. This paper reports that it is desirable from economic and ALARA perspectives to transfer these canisters directly from the plant to the MRS. To this end, it is necessary that the multiassembly sealed canisters, which have been licensed for storage under 10CFR72, be qualified for shipment within a suitable shipping cask under the rules of 10CFR71. Preliminary work performed to date indicates that it is feasible to license a current canister design for transportation, and work is proceeding on obtaining NRC approval

  19. Seals for sealing a pressure vessel such as a nuclear reactor vessel or the like

    International Nuclear Information System (INIS)

    Bruns, H.J.; Huelsermann, K.H.

    1975-01-01

    A description is given of seals for sealing a pressure vessel such as a nuclear reactor vessel, steam boiler vessel, or any other vessel which is desirably sealed against pressure of the type including a housing and a housing closure that present opposed vertical sealing surfaces which define the sides of a channel. The seals of the present invention comprise at least one sealing member disposed in the channel, having at least one stop face, a base portion and two shank portions extending from the base portion to form a groove-like recess. The shank portions are provided with sealing surfaces arranged to mate with the opposed vertical pressure vessel sealing surfaces. A shank-spreading wedge element also disposed in the channel has at least one stop face and is engaged in the groove-like recess with the sealing member and wedge element stop face adjacent to each other

  20. Seal for fluid forming tools

    Science.gov (United States)

    Golovashchenko, Sergey Fedorovich [Beverly Hills, MI; Bonnen, John Joseph Francis [Milford, MI

    2012-03-20

    An electro-hydraulic forming tool for forming a sheet metal blank in a one-sided die has first and second rigid rings that engage opposite sides of a sheet metal blank. The rigid rings are contained within slots on a die portion and a hydraulic force applicator portion of the forming tool. The seals are either resiliently biased by an elastomeric member or inherently resiliently biased into contact with the blank.

  1. Seed Treatment. Manual 92.

    Science.gov (United States)

    Missouri Univ., Columbia. Agricultural Experiment Station.

    This training manual provides information needed to meet minimum EPA standards for certification as a commercial applicator of pesticides in the seed treatment category. The text discusses pests commonly associated with seeds; seed treatment pesticides; labels; chemicals and seed treatment equipment; requirements of federal and state seed laws;…

  2. Seed Treatment. Bulletin 760.

    Science.gov (United States)

    Lowery, Harvey C.

    This manual gives a definition of seed treatment, the types of seeds normally treated, diseases and insects commonly associated with seeds, fungicides and insecticides used, types of equipment used for seed treatment, and information on labeling and coloring of treated seed, pesticide carriers, binders, stickers, and safety precautions. (BB)

  3. Steam Turbine Flow Path Seals (a Review)

    Science.gov (United States)

    Neuimin, V. M.

    2018-03-01

    Various types of shroud, diaphragm, and end seals preventing idle leak of working steam are installed in the flow paths of steam turbine cylinders for improving their efficiency. Widely known labyrinth seals are most extensively used in the Russian turbine construction industry. The category of labyrinth seals also includes seals with honeycomb inserts. The developers of seals with honeycomb inserts state that the use of such seals makes it possible to achieve certain gain due to smaller leaks of working fluid and more reliable operation of the system under the conditions in which the rotor rotating parts may rub against the stator elements. However, a positive effect can only be achieved if the optimal design parameters of the honeycomb structure are fulfilled with due regard to the specific features of its manufacturing technology and provided that this structure is applied in a goal-seeking manner in the seals of steam and gas turbines and compressors without degrading their vibration stability. Calculated and preliminary assessments made by experts testify that the replacement of conventional labyrinth seals by seals with honeycomb inserts alone, due to which the radial gaps in the shroud seal can be decreased from 1.5 to 0.5 mm, allows the turbine cylinder efficiency to be increased at the initial stage by approximately 1% with the corresponding gain in the turbine set power output. The use of rectangular-cellular seals may result, according to estimates made by their developers, in a further improvement of turbine efficiency by 0.5-1.0%. The labor input required to fabricate such seals is six to eight times smaller than that to fabricate labyrinth seals with honeycomb inserts. Recent years have seen the turbine construction companies of the United States and Germany advertising the use of abradable (sealing) coatings (borrowed from the gas turbine construction technology) in the turbine designs instead of labyrinth seals. The most efficient performance of

  4. Design optimization of seal structure for sealing liquid by magnetic fluids

    International Nuclear Information System (INIS)

    Liu Tonggang; Cheng Yusheng; Yang Zhiyi

    2005-01-01

    The durability of the magnetic fluid seal clearly decreases when sealing another liquid because of the interface instability caused by the applied magnetic field and the velocity difference of the two liquids. With an intention to establish a stable interface during sealing liquid, a new magnetic fluid seal was developed in this paper. The parameters of the structure were optimized by a simulation apparatus. And the magnetic fluid seal designed based on the optimum parameters shows good performance and long life for sealing lubricating oil

  5. Actively controlled shaft seals for aerospace applications

    Science.gov (United States)

    Salant, Richard F.

    1995-07-01

    This study experimentally investigates an actively controlled mechanical seal for aerospace applications. The seal of interest is a gas seal, which is considerably more compact than previous actively controlled mechanical seals that were developed for industrial use. In a mechanical seal, the radial convergence of the seal interface has a primary effect on the film thickness. Active control of the film thickness is established by controlling the radial convergence of the seal interface with a piezoelectric actuator. An actively controlled mechanical seal was initially designed and evaluated using a mathematical model. Based on these results, a seal was fabricated and tested under laboratory conditions. The seal was tested with both helium and air, at rotational speeds up to 3770 rad/sec, and at sealed pressures as high as 1.48 x 10(exp 6) Pa. The seal was operated with both manual control and with a closed-loop control system that used either the leakage rate or face temperature as the feedback. The output of the controller was the voltage applied to the piezoelectric actuator. The seal operated successfully for both short term tests (less than one hour) and for longer term tests (four hours) with a closed-loop control system. The leakage rates were typically 5-15 slm (standard liters per minute), and the face temperatures were generally maintained below 100C. When leakage rate was used as the feedback signal, the setpoint leakage rate was typically maintained within 1 slm. However, larger deviations occurred during sudden changes in sealed pressure. When face temperature was used as the feedback signal, the setpoint face temperature was generally maintained within 3 C, with larger deviations occurring when the sealed pressure changes suddenly. the experimental results were compared to the predictions from the mathematical model. The model was successful in predicting the trends in leakage rate that occurred as the balance ratio and sealed pressure changed

  6. Vacuum sealing with a spiral grooved gas dynamic seal

    International Nuclear Information System (INIS)

    Sawada, Tadashi

    1979-01-01

    Gas dynamic seals with rectangular spiral grooves are studied theoretically taking the effects of sidewalls of the grooves and the effects of gas compressibility into account, and slip boundary conditions are employed. The results are compared with the existing experimental data and the validity of the theory is confirmed over a wide pressure range except for the extremely low pressures. Suggestions are made regarding the choice of the geometrical dimensions, i.e., aspect ratio, helix angle, clearance parameter and groove width ratio. (author)

  7. Seal analysis technology for reactor pressure vessel

    International Nuclear Information System (INIS)

    Zheng Liangang; Zhang Liping; Yang Yu; Zang Fenggang

    2009-01-01

    There is the coolant with radiation, high temperature and high pressure in the reactor pressure vessel (RPV). It is closely correlated to RPV sealing capability whether the whole nuclear system work well or not. The aim of this paper is to study the seal analysis method and technology, such as the pre-tensioning of the bolt, elastoplastic contact and coupled technology of thermal and structure. The 3 D elastoplastic seal analysis method really and generally consider the loads and model the contact problem with friction between the contact plates. This method is easier than the specialized seal program and used widely. And it is more really than the 2 D seal analysis method. This 3 D elastoplastic seal analysis method has been successfully used in the design and analysis of RPV. (authors)

  8. Guide to optimized replacement of equipment seals

    International Nuclear Information System (INIS)

    Gleason, J.F.

    1990-03-01

    A reevaluation of current scheduled replacement intervals of polymeric seals in plant equipment can achieve significant benefits. Information is provided which has the potential for increasing replacement intervals based on better information on how seals have performed through unique nuclear industry tests to qualify equipment, improved elastomers and increased knowledge of the failure mechanisms and related performance. The research was performed by reviewing applications of elastomeric seals in nuclear plants and practice associated with defining seal replacement intervals in the nuclear power and other industries. Performance indicators and how they predict degradation of seals were evaluated. Guidelines and a flow chart for reevaluating seal replacement intervals are provided. 29 refs., 38 figs., 8 tabs

  9. A seal analyzer for testing container integrity

    International Nuclear Information System (INIS)

    McDaniel, P.; Jenkins, C.

    1988-01-01

    This paper reports on the development of laboratory and production seal analyzer that offers a rapid, nondestructive method of assuring the seal integrity of virtually any type of single or double sealed container. The system can test a broad range of metal cans, drums and trays, membrane-lidded vessels, flexible pouches, aerosol containers, and glass or metal containers with twist-top lids that are used in the chemical/pesticide (hazardous materials/waste), beverage, food, medical and pharmaceutical industries

  10. Development of advanced seals for space propulsion turbomachinery

    Science.gov (United States)

    Hendricks, Robert C.; Liang, Anita D.; Childs, Dara W.; Proctor, Margaret P.

    1992-04-01

    Current activities in seals for space propulsion turbomachinery that NASA sponsors are surveyed. The overall objective is to provide the designer and researcher with the concepts and data to control seal dynamics and leakage. Included in the program are low-leakage seals, such as the brush seal, the 'ceramic rope' seal, low-leakage seals for liquid oxygen turbopumps, face seals for two phase flow, and swirl brakes for stability. Two major efforts are summarized: a seal dynamics in rotating machinery, and an effort in seal code development.

  11. Management of disused sealed sources

    International Nuclear Information System (INIS)

    Lukauskas, D.; Skridaila, N.

    2003-01-01

    The report presents the requirements on management of disused sealed sources in Lithuania; disused sealed source disposal facilities; performed safety analysis and planed repository safety improvements. The requirements on pre-disposal management of Disused Sealed Sources (DSS) are presented. The requirements on disposal of short lived VLLW and LILW (A, B and C classes) radioactive waste approved in 2002-2003. Generic Waste Acceptance Criteria for Near Surface Disposal, P-2003-01 approved in 2003. Requirements on disposal of Low and intermediate level long lived waste do not exist (D and E classes). Requirements for the disposal of disused sealed sources (F class) do not exist. Disposal method for the F class - Near Surface or Deep geological repository, depending on the waste acceptance criteria. Only one repository for institutional radioactive waste exist in Lithuania - Maisiagala repository. It is near surface RADON type disposal facility, built in 1963 and closed in 1988. It was constructed of the monolithic reinforced concrete with the dimensions 5 m x 15 m x 3 m, the thickness of the sidewalls is about 0.25 m and the thickness of the bottom is about 0.2 m. The overall volume is about 200 m 3 . At time of closure only three fifths of the volume had been filled. The empty two fifths of the vault were filled with concrete, then with sand, then with the concrete (0.01 m), hot bitumen and the 0.05 m asphalt layers. Monolithic concrete that was covered with bitumen and 0.05 m thick layer of asphalt closed the vault. Sand layer the thickness of which was not less than 1.2 m formed the cap. Disused radioactive sources embedded in a biological shielding were buried together with their shielding, the sources without the shielding were buried in two stainless steel containers. The total activity of buried radioactive nuclides is 3.42.10 -15 Bq (calculated according the documentation). There are some uncertainties about the inventory: from 1963 to 1973. After the

  12. Reusable tamper-indicating security seal

    International Nuclear Information System (INIS)

    Ryan, M.J.

    1981-01-01

    A reusable tamper-indicating mechanical security seal for use in safeguarding nuclear material has been developed. The high-security seal displays an unpredictable, randomly selected, five-digit code each time it is used. This five digit code serves the same purpose that the serial number does for conventional non-reusable seals - a unique identifier for each use or application. The newly developed reusable seal is completely enclosed within a seamless, tamper-indicating, plastic jacket. The jacket is designed to reveal any attempts to penetrate, section or to chemically remove and replace with a counterfeit for surreptitious purposes

  13. Seal for an object containing nuclear fuel

    International Nuclear Information System (INIS)

    Scheuerpflug, W.; Nentwich, D.

    1977-01-01

    This seal which cannot be counterfeited, specially for sealing nuclear objects, e.g. fuel rods, not only makes any damage which has taken place obvious, but makes identification according to a key possible. For this purpose a minimum number of 'particles' or small bodies, which are identical but of different permeability, are fixed inside a short tube during 'loading' of the seal in a certain or an accidental sequence. The sequence of the spheres, which represents a key, can only be determined by special electromagnetic measuring equipment. On first opening the seal, this key sequence is irrevocably destroyed. (HP) [de

  14. Upgrading primary heat transport pump seals

    International Nuclear Information System (INIS)

    Graham, T.; Metcalfe, R.; Rhodes, D.; McInnes, D.

    1995-01-01

    Changes in the operating environment at the Bruce-A Nuclear Generating Station created the need for an upgraded Primary Heat Transport Pump (PHTP) seal. In particular, the requirement for low pressure running during more frequent start-ups exposed a weakness of the CAN2 seal and reduced its reliability. The primary concern at Bruce-A was the rotation of the CAN2 No. 2 stators in their holders. The introduction of low pressure running exacerbated this problem, giving rapid wear of the stator back face, overheating, and thermocracking. In addition, the resulting increase in friction between the stator and its holder increased stationary-side hysteresis and thereby changed the seal characteristic to the point where interseal pressure oscillations became prevalent. The resultant increased hysteresis also led to hard rubbing of the seal faces during temperature transients. An upgraded seal was required for improved reliability to avoid forced outages and to reduce maintenance costs. This paper describes this upgraded 'replacement seal' and its performance history. In spite of the 'teething' problems detailed in this paper, there have been no forced outages due to the replacement seal, and in the words of a seal maintenance worker at Bruce-A, 'it allows me to go home and sleep at night instead of worrying about seal failures.' (author)

  15. Ductile alloys for sealing modular component interfaces

    Energy Technology Data Exchange (ETDEWEB)

    Marra, John J.; Wessell, Brian J.; James, Allister W.; Marsh, Jan H.; Gear, Paul J.

    2017-08-08

    A vane assembly (10) having: an airfoil (12) and a shroud (14) held together without metallurgical bonding there between; a channel (22) disposed circumferentially about the airfoil (12), between the airfoil (12) and the shroud (14); and a seal (20) disposed in the channel (22), wherein during operation of a turbine engine having the vane assembly (10) the seal (20) has a sufficient ductility such that a force generated on the seal (20) resulting from relative movement of the airfoil (12) and the shroud (14) is sufficient to plastically deform the seal (20).

  16. Quick-sealing design for radiological containment

    International Nuclear Information System (INIS)

    Rampdla, D.S.; Speer, E.

    1991-01-01

    This patent describes a quick-sealing assembly and method for forming an adhesive seal on opposite sides of a mechanical seal for a flexible containment bag of the type used for working with radioactively contaminated objects. The assembly includes an elongated mechanical fastener having opposing engaging members affixed at a predetermined distance from each of the elongated edges, with an adhesive layer formed between the mechanical fastener and the elongated edge such that upon engagement of the mechanical fastener and adhesive layers to opposing containment fabric, a neat triple hermetic seal is formed

  17. Quick-sealing design for radiological containment

    International Nuclear Information System (INIS)

    Rampolia, D.S.; Speer, E.

    1990-01-01

    This patent describes a quick-sealing assembly and method for forming an adhesive seal on opposite sides of a mechanical seal for a flexible containment bag of the type used for working with radioactively contaminated objects. The assembly includes an elongated mechanical fastener having opposing engaging members affixed at a predetermined distance from each of the elongated edges, with an adhesive layer formed between the mechanical fastener and the elongated edge such that upon engagement of the mechanical fastener and adhesive layers to opposing containment fabric, a neat triple hermetic seal is formed

  18. Quick-sealing design for radiological containment

    Science.gov (United States)

    Rampolia, Donald S.; Speer, Elmer

    1990-01-01

    A quick-sealing assembly and method for forming an adhesive seal on opposite sides of a mechanical seal for a flexible containment bag of the type used for working with radioactively contaminated objects. The assembly includes an elongated mechanical fastener having opposing engaging members affixed at a predetermined distance from each of the elongated edges, with an adhesive layer formed between the mechanical fastener and the elongated edge such that upon engagement of the mechanical fastener and adhesive layers to opposing containment fabric, a neat triple hermetic seal is formed.

  19. Bingham Sealing and Application in Vacuum Clamping

    Science.gov (United States)

    Yao, S. M.; Teo, Wee Kin; Geng, Zunmin; Turner, Sam; Ridgway, Keith

    2011-12-01

    Vacuum clamping is extensively used in shell machining. In this paper a Bingham Sealing (BS) is presented and formulized based on Bingham plastic performance. The sealing capability of BS is evaluated in various cases. A new Bingham plastic is developed and the yield stress is measured. The performances of "O"ring sealing and BS with the developed Bingham plastic are compared to the static experiment. In this experiment the same vacuum is achieved and the distortion of the blade with BS is better than that with "O" ring sealing.

  20. Bingham Sealing and Application in Vacuum Clamping

    International Nuclear Information System (INIS)

    Yao, S M; Teo, Wee Kin; Geng Zunmin; Turner, Sam; Ridgway, Keith

    2011-01-01

    Vacuum clamping is extensively used in shell machining. In this paper a Bingham Sealing (BS) is presented and formulized based on Bingham plastic performance. The sealing capability of BS is evaluated in various cases. A new Bingham plastic is developed and the yield stress is measured. The performances of Or ing sealing and BS with the developed Bingham plastic are compared to the static experiment. In this experiment the same vacuum is achieved and the distortion of the blade with BS is better than that with 'O' ring sealing.

  1. Byzantine seals from the Ras fortress

    Directory of Open Access Journals (Sweden)

    Ivanišević Vujadin

    2013-01-01

    Full Text Available In this paper, seals found at the location of the Ras fortress (Tvrđava Ras have been published. Inscriptions on these seals show that they used to belong to persons which could be identified with certain military commanders who served under Alexios I Komnenos. The seals in question are: the seals of protonobelissimos Eustathios Kamytzes, Constantine Dalassenos Doukas, protoproedros and doux Constantine Kekaumenos and a certain person called Alexios. [Projekat Ministarstva nauke Republike Srbije, br. 177021 i br. 177032

  2. 48 CFR 14.101 - Elements of sealed bidding.

    Science.gov (United States)

    2010-10-01

    ... CONTRACTING METHODS AND CONTRACT TYPES SEALED BIDDING Use of Sealed Bidding 14.101 Elements of sealed bidding. Sealed bidding is a method of contracting that employs competitive bids, public opening of bids, and... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Elements of sealed bidding...

  3. Ceramic/metal seals. [refractory materials for hermetic seals for lighium-metal sulfide batteries

    Science.gov (United States)

    Bredbenner, A. M.

    1977-01-01

    Design criteria are discussed for a hermetic seal capable of withstanding the 450 C operating temperature of a lithium-metal sulfide battery system. A mechanical seal consisting of two high strength alloy metal sleeves welded or brazed to a conductor assembly and pressed onto a ceramic is described. The conductor center passes through the ceramic but is not sealed to it. The seal is effected on the outside of the taper where the tubular part is pressed down over and makes contact.

  4. Seals at sea: modelling seal distribution in the German bight based on aerial survey data

    NARCIS (Netherlands)

    Herr, H.; Scheidat, M.; Lehnert, K.; Siebert, U.

    2009-01-01

    The Wadden Sea is an important habitat for harbour seals and grey seals. They regularly haul-out on sandbanks and islands along the coast. Comparably little is known about the time seals spend at sea and how they use the remainder of the North Sea. Yet, human activity in offshore waters is

  5. Albinistic common seals (Phoca vitulina) and melanistic grey seals (Halichoerus grypus) rehabilitated in the Netherlands

    NARCIS (Netherlands)

    Osinga, Nynke; 't Hart, Pieter; Vader, Pieter C. van Voorst

    2010-01-01

    The Seal Rehabilitation and Research Centre (SRRC) in Pieterburen, The Netherlands, rehabilitates seals from the waters of the Wadden Sea, North Sea and Southwest Delta area. Incidental observations of albinism and melanism in common and grey seals are known from countries surrounding the North Sea.

  6. Corkscrew Seals: Grey Seal (Halichoerus grypus) Infanticide and Cannibalism May Indicate the Cause of Spiral Lacerations in Seals.

    Science.gov (United States)

    Brownlow, Andrew; Onoufriou, Joseph; Bishop, Amanda; Davison, Nicholas; Thompson, Dave

    2016-01-01

    Large numbers of dead seals with characteristic spiral lesions have been washing ashore around the North Atlantic over the past two decades. Interactions with ship propellers and shark predation have been suggested as the likely causal mechanisms. However, new evidence points towards a more likely candidate: grey seal predation. An adult male grey seal was observed and recorded catching, killing and eating five weaned grey seal pups over a period of one week on the Isle of May, Scotland. A further 9 carcasses found in the same area exhibited similar injuries. Post mortem analysis of lesions indicated the wound characteristics were similar to each other and in 12 of the 14 carcasses analysed, were indistinguishable from carcasses previously attributed to propeller interaction. We therefore propose that most of the seal carcasses displaying spiral lacerations in the UK are caused by grey seal predation. Cases in other locations should be re-evaluated using the scoring system presented here to identify whether grey seal predation is a major cause of mortality in phocid seals.

  7. Barley seed aging

    NARCIS (Netherlands)

    Nagel, Manuela; Kodde, Jan; Pistrick, Sibylle; Mascher, Martin; Börner, Andreas; Groot, Steven P.C.

    2016-01-01

    Experimental seed aging approaches intend to mimic seed deterioration processes to achieve a storage interval reduction. Common methods apply higher seed moisture levels and temperatures. In contrast, the “elevated partial pressure of oxygen” (EPPO) approach treats dry seed stored at ambient

  8. Machine Vision Inspection of Polymeric Traypack Seal Areas

    National Research Council Canada - National Science Library

    Coburn, John

    2002-01-01

    .... Since entrapped matter can lead to open seals, defects, and seal anomalies, a method of measurement for seal area contamination is useful in quantifying effects of filler changes, line speeds, and product formulations...

  9. Sealing of boreholes using natural, compatible materials: Granular salt

    International Nuclear Information System (INIS)

    Finley, R.E.; Zeuch, D.H.; Stormont, J.C.; Daemen, J.J.K.

    1994-01-01

    Granular salt can be used to construct high performance permanent seals in boreholes which penetrate rock salt formations. These seals are described as seal systems comprised of the host rock, the seal material, and the seal rock interface. The performance of these seal systems is defined by the complex interactions between these seal system components through time. The interactions are largely driven by the creep of the host formation applying boundary stress on the seal forcing host rock permeability with time. The immediate permeability of these seals is dependent on the emplaced density. Laboratory test results suggest that careful emplacement techniques could results in immediate seal system permeability on the order of 10 -16 m 2 to 10 -18 m 2 (10 -4 darcy to 10 -6 ). The visco-plastic behavior of the host rock coupled with the granular salts ability to ''heal'' or consolidate make granular salt an ideal sealing material for boreholes whose permanent sealing is required

  10. Performance oriented guidance for Mississippi chip seals - volume I.

    Science.gov (United States)

    2013-12-01

    A five year laboratory study was conducted to investigate near surface properties of flexible pavements in relation to : how they are affected by bituminous surface treatments. Chip seals and scrub seals (a specialized type of chip seal) : were the f...

  11. Design, construction and testing of underground seals

    CSIR Research Space (South Africa)

    Cook, AP

    2000-01-01

    Full Text Available the structural design or material requirements for seals, but also require an overpressure of 140 kPa, and this within 24 hours of construction. Approved systems for seal construction from MSHA are concrete blocks, Omega 384 foam blocks, cementitious foam........................................................................................................................ 7 2.1.2 Masonry ....................................................................................................................... 7 2.1.3 Concrete...

  12. Space Environment's Effects on Seal Materials

    Science.gov (United States)

    deGroh, Henry C., III; Daniels, Christopher C.; Dunlap, Patrick; Miller, Sharon; Dever, Joyce; Waters, Deborah; Steinetz, Bruce M.

    2007-01-01

    A Low Impact Docking System (LIDS) is being developed by the NASA Johnson Space Center to support future missions of the Crew Exploration Vehicle (CEV). The LIDS is androgynous, such that each system half is identical, thus any two vehicles or modules with LIDS can be coupled. Since each system half is a replica, the main interface seals must seal against each other instead of a conventional flat metal surface. These sealing surfaces are also expected to be exposed to the space environment when vehicles are not docked. The NASA Glenn Research Center (NASA GRC) is supporting this project by developing the main interface seals for the LIDS and determining the durability of candidate seal materials in the space environment. In space, the seals will be exposed to temperatures of between 50 to 50 C, vacuum, atomic oxygen, particle and ultraviolet radiation, and micrometeoroid and orbital debris (MMOD). NASA GRC is presently engaged in determining the effects of these environments on our candidate elastomers. Since silicone rubber is the only class of seal elastomer that functions across the expected temperature range, NASA GRC is focusing on three silicone elastomers: two provided by Parker Hannifin (S0-899-50 and S0-383-70) and one from Esterline Kirkhill (ELA-SA-401). Our results from compression set, elastomer to elastomer adhesion, and seal leakage tests before and after various simulated space exposures will be presented.

  13. System for inspection of package seal integrity

    Science.gov (United States)

    Gibson, Terry G.

    1995-10-01

    There is an increasing acceptance of reduced waste packaging methods for pharmaceutical and medical products. The high level of product integrity must be maintained, while manufacturing lines are required to increase production rates. To ensure their confidence in these packaging methods, manufacturers have turned to process validation as one method of check. In addition to that effort, automated on-line inspection has become increasingly important. Automated inspection can be used to augment manual inspection techniques that are viable at slower production rates. In this paper we explore the elements of a systematic approach that can provide 100% automatic inspection of product seals at full production rates. The various materials used to seal packages effect the system configuration. One such package sealing material is highly specular (mirror-like) laminated foil. A characteristic of this packaging method is its ability to reflect nearly all of the light from the surface. However, the heat process required to bond the seal to the package creates a coining effect where a uniform, low to medium intensity light source, transmitted at a low incident angle, can be used to identify seal defects. It is equally difficult to inspect package seals that are opaque, translucent, or transparent. Each seal material requires a specific lighting solution. When using reflective material, great care must be taken to develop and integrate the lighting method to an automated package seal inspection system.

  14. Performance evaluation of chip seals in Idaho.

    Science.gov (United States)

    2010-08-01

    The intent of this research project is to identify a wide variety of parameters that influence the performance of pavements treated via chip seals within the State of Idaho. Chip sealing is currently one of the most popular methods of maintenance for...

  15. Population structure of ice-breeding seals.

    Science.gov (United States)

    Davis, Corey S; Stirling, Ian; Strobeck, Curtis; Coltman, David W

    2008-07-01

    The development of population genetic structure in ice-breeding seal species is likely to be shaped by a combination of breeding habitat and life-history characteristics. Species that return to breed on predictable fast-ice locations are more likely to exhibit natal fidelity than pack-ice-breeding species, which in turn facilitates the development of genetic differentiation between subpopulations. Other aspects of life history such as geographically distinct vocalizations, female gregariousness, and the potential for polygynous breeding may also facilitate population structure. Based on these factors, we predicted that fast-ice-breeding seal species (the Weddell and ringed seal) would show elevated genetic differentiation compared to pack-ice-breeding species (the leopard, Ross, crabeater and bearded seals). We tested this prediction using microsatellite analysis to examine population structure of these six ice-breeding species. Our results did not support this prediction. While none of the Antarctic pack-ice species showed statistically significant population structure, the bearded seal of the Arctic pack ice showed strong differentiation between subpopulations. Again in contrast, the fast-ice-breeding Weddell seal of the Antarctic showed clear evidence for genetic differentiation while the ringed seal, breeding in similar habitat in the Arctic, did not. These results suggest that the development of population structure in ice-breeding phocid seals is a more complex outcome of the interplay of phylogenetic and ecological factors than can be predicted on the basis of breeding substrate and life-history characteristics.

  16. Earlier pupping in harbour seals, Phoca vitulina

    NARCIS (Netherlands)

    Reijnders, P.J.H.; Brasseur, S.M.J.M.; Meesters, H.W.G.

    2010-01-01

    The annual reproductive cycle of most seal species is characterized by a tight synchrony of births. Typically, timing of birth shows little inter-annual variation. Here, however we show that harbour seals Phoca vitulina from the Wadden Sea (southeast North Sea) have shortened their yearly cycle,

  17. 39 CFR 2.4 - Seal.

    Science.gov (United States)

    2010-07-01

    ... 39 Postal Service 1 2010-07-01 2010-07-01 false Seal. 2.4 Section 2.4 Postal Service UNITED STATES... Secretary of State, and is required by 39 U.S.C. 207 to be judicially noticed. The Seal shall be in the... description of the Postal Service emblem is described at 39 CFR 221.7. ...

  18. Space Environment Effects on Silicone Seal Materials

    Science.gov (United States)

    deGroh, Henry C., III; Daniels, Christopher C.; Dever, Joyce A.; Miller, Sharon K.; Waters, Deborah L.; Finkbeiner, Joshua R.; Dunlap, Patrick H.; Steinetz, Bruce M.

    2010-01-01

    A docking system is being developed by the NASA to support future space missions. It is expected to use redundant elastomer seals to help contain cabin air during dockings between two spacecraft. The sealing surfaces are exposed to the space environment when vehicles are not docked. In space, the seals will be exposed to temperatures between 125 to -75 C, vacuum, atomic oxygen, particle and ultraviolet radiation, and micrometeoroid and orbital debris (MMOD). Silicone rubber is the only class of space flight-qualified elastomeric seal material that functions across the expected temperature range. NASA Glenn has tested three silicone elastomers for such seal applications: two provided by Parker (S0899-50 and S0383-70) and one from Esterline (ELA-SA-401). The effects of atomic oxygen (AO), UV and electron particle radiation, and vacuum on the properties of these three elastomers were examined. Critical seal properties such as leakage, adhesion, and compression set were measured before and after simulated space exposures. The S0899-50 silicone was determined to be inadequate for extended space seal applications due to high adhesion and intolerance to UV, but both S0383-70 and ELA-SA-401 seals were adequate.

  19. 19 CFR 101.7 - Customs seal.

    Science.gov (United States)

    2010-04-01

    ... 19 Customs Duties 1 2010-04-01 2010-04-01 false Customs seal. 101.7 Section 101.7 Customs Duties U.S. CUSTOMS AND BORDER PROTECTION, DEPARTMENT OF HOMELAND SECURITY; DEPARTMENT OF THE TREASURY GENERAL PROVISIONS § 101.7 Customs seal. (a) Design. According to the design furnished by the Department...

  20. Dura Seal recommendations for nuclear power plants

    International Nuclear Information System (INIS)

    Anon.

    1980-01-01

    Reactor systems (BWR, PWR and Candu) are briefly reviewed with reference to the pumping services encountered in each system, to indicate the conditions imposed on mechanical seals for nuclear power plant liquid handling equipment. A description of the Dura Seals used in each service is included. (U.K.)

  1. Sealing Occlusal Dentin Caries in Permanent Molars

    DEFF Research Database (Denmark)

    Qvist, Vibeke; Borum, Mette Kit; Møller, Kirsten Dynes

    2017-01-01

    .001). The median survival time for sealings not replaced by restorations was 7.3 y (CI, 6.4 y to NA). Survival of sealings was increased in patients with low caries risk and/or excellent oral hygiene, second molars compared with first molars, and lesions not extending the middle one-third of the dentin. Survival...

  2. Seroprevalence of Antibodies against Seal Influenza A(H10N7) Virus in Harbor Seals and Gray Seals from the Netherlands

    NARCIS (Netherlands)

    Bodewes, Rogier; Garcia, Ana Rubio; Brasseur, Sophie M.; Conteras, Guillermo J.S.; De Bildt, Van Marco W.G.; Koopmans, Marion P.G.; Osterhaus, Albert D.M.E.; Kuiken, Thijs

    2015-01-01

    In the spring and summer 2014, an outbreak of seal influenza A(H10N7) virus infection occurred among harbor seals (Phoca vitulina) off the coasts of Sweden and Denmark. This virus subsequently spread to harbor seals off the coasts of Germany and the Netherlands. While thousands of seals were

  3. Seroprevalence of Antibodies against Seal Influenza A(H10N7) Virus in Harbor Seals and Gray Seals from the Netherlands

    NARCIS (Netherlands)

    Bodewes, Rogier; Rubio García, Ana; Brasseur, Sophie M; Sanchez Conteras, Guillermo J; van de Bildt, Marco W G; Koopmans, Marion P G; Osterhaus, Albert D M E; Kuiken, Thijs

    2015-01-01

    In the spring and summer 2014, an outbreak of seal influenza A(H10N7) virus infection occurred among harbor seals (Phoca vitulina) off the coasts of Sweden and Denmark. This virus subsequently spread to harbor seals off the coasts of Germany and the Netherlands. While thousands of seals were

  4. Effects of sonic booms on breeding gray seals and harbor seals on Sable Island, Canada.

    Science.gov (United States)

    Perry, Elizabeth A; Boness, Daryl J; Insley, Stephen J

    2002-01-01

    The Concorde produces audible sonic booms as it passes 15 km north of Sable Island, Nova Scotia, where gray and harbor seals occur year round. The purpose of this research was to assess how sonic booms affect these seals. The intensity of the booms was measured and three types of data (beach counts, frequency of behavior, and heart rate) were collected before and after booms during the breeding seasons of the two species. In addition to the data taken during breeding, beach counts were made before and after booms during the gray seal moult. The greatest range in overpressure within a single boom was 2.70 psf during gray seal breeding and 2.07 psf during harbor seal breeding. No significant differences were found in the behavior or beach counts of gray seals following sonic booms, regardless of the season. Beach counts and most behaviors of harbor seals also did not differ significantly following booms, however, harbor seals became more vigilant. The heart rates of four gray seal mothers and three pups showed no clear change as a result of booms, but six male harbor seals showed a nonsignificant tendency toward elevated heart rates during the 15-s interval of the boom. These results suggest sonic booms produced by the Concorde, in level flight at altitude and producing on average a sonic boom of 0.9 psf, do not substantially affect the breeding behavior of gray or harbor seals.

  5. Active Infrared Thermography for Seal Contamination Detection in Heat-Sealed Food Packaging

    Directory of Open Access Journals (Sweden)

    Karlien D’huys

    2016-11-01

    Full Text Available Packaging protects food products from environmental influences, assuring quality and safety throughout shelf life if properly performed. Packaging quality depends on the quality of the packaging material and of the closure or seal. A common problem possibly jeopardizing seal quality is the presence of seal contamination, which can cause a decreased seal strength, an increased packaging failure risk and leak formation. Therefore, early detection and removal of seal contaminated packages from the production chain is crucial. In this work, a pulsed-type active thermography method using the heated seal bars as an excitation source was studied for detecting seal contamination. Thermal image sequences of contaminated seals were recorded shortly after sealing. The detection performances of six thermal image processing methods, based on a single frame, a fit of the cooling profiles, thermal signal reconstruction, pulsed phase thermography, principal component thermography and a matched filter, were compared. High resolution digital images served as a reference to quantify seal contamination, and processed thermal images were mapped to these references. The lowest detection limit (equivalent diameter 0.60 mm was obtained for the method based on a fit of the cooling profiles. Moreover, the detection performance of this method did not depend strongly on the time after sealing at which recording of the thermal images was started, making it a robust and generally applicable method.

  6. Investigations of Shuttle Main Landing Gear Door Environmental Seals

    Science.gov (United States)

    Finkbeiner, Joshua; DeMange, Jeff; Dunlap, Pat; Steinetz, Bruce; Newswander, Daniel

    2006-01-01

    The Columbia Accident investigation Board (CAIB) requested an investigation into the MLG door seals. Initially, the MLG door seals were thought to have been a potential contributor to the loss of Columbia. These suspicions were later found to be untrue, but the seals remained as a cause for concern in future flights. MLG door seals comprised of thermal barrier and environmental seal. This study focuses on the environmental seal for the MLG door.

  7. [Methods for sealing of corneal perforations].

    Science.gov (United States)

    Samoilă, O; Totu, Lăcrămioara; Călugăru, M

    2012-01-01

    A variety of corneal pathology can lead to corneal ulcers and perforations. A deep corneal ulcer may need surgical treatment to allow good volume restoration and reepithelisation. Corneal perforation must be sealed and when the perforation is large, the task of repairing the defect can be underwhelming. The elegant solution is the corneal transplant, but this is not always readily available, especially in undeveloped countries. We present here two cases with different solutions to seal the perforated cornea: the first one has a large peripheral defect and it is successfully sealed with scleral patch and the second one is central with small perforation and is successfully sealed with multilayered amniotic membrane. Both cases are followed for over 12 months and demonstrate good corneal restoration (both on clinical examination and corneal topography). Sclera and amniotic membrane can be used to seal corneal defects when corneal transplant is not readily available.

  8. Properties of Sealing Materials in Groundwater Wells

    DEFF Research Database (Denmark)

    Köser, Claus

    boreholes which in some cases can act as direct openings down to aquifers. The reasons for this may include bad or missing seal. In this context, Schmidt (1999) concluded that there is no proven way to make a clay seal with the desired tightness. This thesis deals primarily with the properties of bentonite...... pellets as sealing material in groundwater wells. The way and the pattern, in which bentonite pellets are deposited, have been shown to have an effect on the swelling pressure of the bentonite seal. During the transport phase of pellets from the terrain to a given sedimentation depth, a sorting process...... on the maximum swelling pressure; i) the bulk density of the sample, and ii) whether the sample is sorted or unsorted. CT scans (Computed Tomography) have been used to evaluate certain properties of bentonite seals in a limited volume. In this context, a set of algorithms to convert CT numbers (HU unit...

  9. Spring loaded compliant seal for high temperature use

    Science.gov (United States)

    Memmen, Robert L; Fedock, John A; Downs, James P

    2013-10-15

    A flexible seal having an X-shaped cross section that forms four contact points on four contact surfaces of two opposed seal slots. The flexible seal is used for a component in which the two seal slots undergo a large deflection such that the opposed slots are not aligned and a rigid seal will not form an adequate seal. The flexible seal can be used in a component of a combustor or a turbine in a gas turbine engine where opposed seal slots undergo the large deflection during operation.

  10. A hybrid floating brush seal (HFBS) for improved sealing and wear performance in turbomachinery applications

    Science.gov (United States)

    Lattime, Scott Byran

    A conceptually new type of seal has been developed for gas turbine applications which dramatically reduces wear and leakage associated with current labyrinth and brush seal technologies. The Hybrid Floating Brush Seal (HFBS) combines brush seal and film riding face seal technologies to create a hybrid seal that allows both axial and radial excursions of the sealed shaft, while simultaneously eliminating interface surface speeds (friction and heat) between the rotor and the brush material that characterize standard brush seal technology. A simple test rig was designed to evaluate feasibility of the HFBS under relatively low pressures and rotational speeds (50psig, 5krpm). A second test stand was created to study the effects of centrifugal force on bristle deflection. A third test facility was constructed for prototype development and extensive room temperature testing at moderate pressures and fairly high rotational speeds (100psig, 40krpm). This test rig also allowed the evaluation of the HFBS during axial movement of a rotating shaft. An analytical model to predict the effects of centrifugal force on the bristles of a rotating brush seal was developed. Room temperature analysis of the HFBS proved successful for relatively high operating rotational velocities at moderate pressures with very acceptable leakage rates for gas turbine engines. Brush seals were able to track rotor speeds up to 24krpm while maintaining sealing integrity. The HFBS's ability to function under axial shaft displacement and synchronous dynamic radial loading was also proven successful. Hydrodynamic performance of the face seal was proven to provide adequate stiffness and load carrying capacity to keep the brush seal from contacting the face seal at pressure drops across the brush of up to 100psi. Leakage performance over standard brush seal and labyrinth technology was quite dramatic. The HFBS showed its sealing advantage using much higher radial interference between the rotor and the bristle

  11. Does the seal licensing system in Scotland have a negative impact on seal welfare?

    Directory of Open Access Journals (Sweden)

    Laetitia Nunny

    2016-08-01

    Full Text Available This study examined the licensing system that permits seal shooting in Scotland, which was established under Part 6 Conservation of Seals of the Marine (Scotland Act 2010. Four approaches were used: data were collated and analyzed from both the Scottish Government and Scottish Marine Animal Stranding Scheme; a survey was sent to current license holders and informal interviews were conducted with key stakeholder types. Between February 2011 and the end of October 2015, 1229 gray seals and 275 common seals were reported shot under license to the Scottish Government. The numbers of seals reported as shot has reduced year-on-year since the licensing system was put in place. While some license holders, notably fish farms, were using some non-lethal forms of deterrent to reduce seal-related damage, these were often used alongside seal shooting. Of the seals reported as shot to the Scottish Government, only a small percentage were also reported to the Scottish Marine Animal Stranding Scheme, despite this being a licensing requirement. Only 2.3% of the shot gray seals and 4.5% of the shot common seals were necropsied. There is evidence from these necropsies that some seals had not died instantly or had not been shot in the manner recommended by the Scottish Seal Management Code of Practice. These preliminary results show that more carcasses need to be recovered and necropsied if the welfare implications of current seal shooting practice are to be properly assessed. The current legislation does not specify closed seasons to protect breeding seals and thirty-five per cent of necropsied seals were pregnant gray seals. Seals have also been shot during their lactation periods when pups are dependent on their mothers. This raises significant welfare concerns. The re-introduction of closed seasons specific to each species of seal is recommended along with greater effort to deploy non-lethal methods. Independent assessment of the number of seals being killed

  12. Ocean climate and seal condition

    Directory of Open Access Journals (Sweden)

    Crocker Daniel E

    2005-03-01

    Full Text Available Abstract Background The condition of many marine mammals varies with fluctuations in productivity and food supply in the ocean basin where they forage. Prey is impacted by physical environmental variables such as cyclic warming trends. The weaning weight of northern elephant seal pups, Mirounga angustirostris, being closely linked to maternal condition, indirectly reflects prey availability and foraging success of pregnant females in deep waters of the northeastern Pacific. The aim of this study was to examine the effect of ocean climate on foraging success in this deep-diving marine mammal over the course of three decades, using cohort weaning weight as the principal metric of successful resource accrual. Results The mean annual weaning weight of pups declined from 1975 to the late 1990s, a period characterized by a large-scale, basin-wide warm decadal regime that included multiple strong or long-duration El Niños; and increased with a return to a cool decadal regime from about 1999 to 2004. Increased foraging effort and decreased mass gain of adult females, indicative of reduced foraging success and nutritional stress, were associated with high ocean temperatures. Conclusion Despite ranging widely and foraging deeply in cold waters beyond coastal thermoclines in the northeastern Pacific, elephant seals are impacted significantly by ocean thermal dynamics. Ocean warming redistributes prey decreasing foraging success of females, which in turn leads to lower weaning mass of pups. Annual fluctuations in weaning mass, in turn, reflect the foraging success of females during the year prior to giving birth and signals changes in ocean temperature cycles.

  13. Study on sealing of boreholes

    International Nuclear Information System (INIS)

    1987-01-01

    A bibliographical research on the problem of the backfilling and sealing of boreholes, shafts and tunnels for radioactive waste disposal has been carried out. Various materials - both natural and artificial - like clay, industrial cement, polymer concrete, geothermical and magnesium cement have been examined. Their main physico-chemical and durability characteristics have been examined. The problem of the interaction between the sealing and the geological environment has been also dealt. The final subject discussed in the bibliography is the damage caused to the host formation by the excavation of shafts and tunnels. The laboratory tests have been performed on a natural clay and other types of material (cement grout, cement grout with expansive additive, cement mortar and remoulded clay) which have been used as plug materials. The main conclusions obtained from the tests are the following: - The permeability of the cement is lower than the permeability of the clay; - no adhesion was observed between clay and cement mortar, with or without expansive additive, when cured under different ambient conditions, but without any application of load; - When curing took place under load, good adhesion was observed between the clay and the cement mortar; - The flow of water in a specimen consisting of a clay core surrounded by remoulded clay is larger than in the natural clay. These results seem to be caused by the different permeabilities of the remoulded and undisturbed clay and not to depend on flow at the contact between the two materials. A remote instrumentation package for the in situ evaluation of the performance of a plug, has been developed. In order to get rid of the uncertainty associated with the infiltration of the cables through the plug a wireless data transmission system, based on acoustic waves, has been developed

  14. Design and development of face seal type sealing plug for advanced heavy water reactor

    International Nuclear Information System (INIS)

    Bansal, S.; Bhattacharyya, S.; Patel, R.J.; Agrawal, R.G.; Vaze, K.K.

    2005-09-01

    Advanced Heavy Water Reactor is a vertical pressure tube type reactor having light water as its coolant and heavy water as moderator. Sealing plug is required to close the pressure boundary of main heat transport system of the reactor by preventing escape of light water/steam From the coolant channel. There are 452 coolant channels in the reactor located in square lattice pitch. Sealing plug is located at the top of each coolant channel (in the top end fitting). Top end fitting is having a stepped bore to create a sealing face. Sealing plug is held through its expanded jaws in a specially provided groove of the end fitting. The plug was designed and prototypes were manufactured considering its functional importance, intricate design and precision machining requirements. Sealing plug consists of about 20 components mostly made up of precipitation hardening stainless steel, which is suitable for water environment and meets other requirements of strength and resistance to wear and galling. Seal disc is a critical component of the sealing plug as it is the pressure-retaining component. It is a circular disc with protruded stem. One face of the seal disc is nickel plated in the peripheral area that creates the sealing by abutting against the sealing face provided in the end fitting. The typical shape and profile of seal disc provides flexibility and allows elastic deformation to assist in locking of sealing plug and creating adequate seating force for effective sealing. Design and development aspects of the sealing plug have been detailed out in this report. Also results of stress analysis and experimental studies for seal disc have been mentioned in the report. Stress analysis and experimental testing was required for the seal disc because high stresses are developed due to its exposure to high pressure and temperature environment of Main Heat Transport system. Hot testing was carried out to simulate the reactor-simulated condition. The performance was found to be

  15. Numerical Investigation of the Effect of Radial Lip Seal Geometry on Sealing Performance

    Science.gov (United States)

    Tok, G.; Parlar, Z.; Temiz, V.

    2018-01-01

    Sealing elements are often needed in industry and especially in machine design. With the change and development of machine technology from day to day, sealing elements show continuous development and change in parallel with these developments. Many factors influence the performance of the sealing elements such as shaft surface roughness, radial force, lip geometry etc. In addition, the radial lip seals must have a certain pre-load and interference in order to provide a good sealing. This also affects the friction torque. Researchers are developing new seal designs to reduce friction losses in mechanical systems. In the presented study, the effect of the lip seal geometry on sealing performance will be examined numerically. The numerical model created for this purpose will be verified with experimental data firstly. In the numerical model, shaft and seal will be modeled as hyper-elastic in 2D and 3D. NBR (Nitrile Butadiene Rubber) as seal material will be analyzed for the rotating shaft state at constant speed by applying a uniform radial force.

  16. Actively controlled shaft seals for aerospace applications

    Science.gov (United States)

    Salant, Richard F.

    The objective of years 4 and 5 of this project (1992 and 1993) is to determine experimentally the behavior and operating characteristics of a controllable mechanical seal, and to identify potential problem areas. A controllable mechanical seal is one in which the thickness of the lubricating film separating the sealing surfaces is adjustable, and can be controlled by an electronic control system, based on information supplied by sensors that monitor the condition of the film. This work builds upon work done during years 1-3, in which a controllable mechanical seal was designed, analyzed, and fabricated. At the beginning of year 4, the mechanical seal and test rig was assembled, and preliminary testing begun. The five major tasks of years 4 and 5 encompass instrumentation, configuration changes of the mechanical seal to optimize its performance, systematic steady state tests, systematic transient tests, and a final report. During this reporting period, significant progress was made on instrumenting the test rig and modifying the design to optimize the seal's performance. Initial steady state tests were also performed.

  17. Tamper-indicating quantum optical seals

    Energy Technology Data Exchange (ETDEWEB)

    Humble, Travis S [ORNL; Williams, Brian P [ORNL

    2015-01-01

    Confidence in the means for identifying when tampering occurs is critical for containment and surveillance technologies. Fiber-optic seals have proven especially useful for actively surveying large areas or inventories due to the extended transmission range and flexible layout of fiber. However, it is reasonable to suspect that an intruder could tamper with a fiber-optic sensor by accurately replicating the light transmitted through the fiber. In this contribution, we demonstrate a novel approach to using fiber-optic seals for safeguarding large-scale inventories with increased confidence in the state of the seal. Our approach is based on the use of quantum mechanical phenomena to offer unprecedented surety in the authentication of the seal state. In particular, we show how quantum entangled photons can be used to monitor the integrity of a fiber-optic cable - the entangled photons serve as active sensing elements whose non-local correlations indicate normal seal operation. Moreover, we prove using the quantum no-cloning theorem that attacks against the quantum seal necessarily disturb its state and that these disturbances are immediately detected. Our quantum approach to seal authentication is based on physical principles alone and does not require the use of secret or proprietary information to ensure proper operation. We demonstrate an implementation of the quantum seal using a pair of entangled photons and we summarize our experimental results including the probability of detecting intrusions and the overall stability of the system design. We conclude by discussing the use of both free-space and fiber-based quantum seals for surveying large areas and inventories.

  18. Compliant Glass Seals for SOFC Stacks

    Energy Technology Data Exchange (ETDEWEB)

    Chou, Yeong -Shyung [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Choi, Jung-Pyung [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Xu, Wei [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Stephens, Elizabeth V. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Koeppel, Brian J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Stevenson, Jeffry W. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Lara-Curzio, Edgar [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2014-04-30

    This report summarizes results from experimental and modeling studies performed by participants in the Solid-State Energy Conversion Alliance (SECA) Core Technology Program, which indicate that compliant glass-based seals offer a number of potential advantages over conventional seals based on de-vitrifying glasses, including reduced stresses during stack operation and thermal cycling, and the ability to heal micro-damage induced during thermal cycling. The properties and composition of glasses developed and/or investigated in these studies are reported, along with results from long-term (up to 5,800h) evaluations of seals based on a compliant glass containing ceramic particles or ceramic fibers.

  19. Infiltrating/sealing proximal caries lesions

    DEFF Research Database (Denmark)

    Martignon, S; Ekstrand, K R; Gomez, J

    2012-01-01

    This randomized split-mouth controlled clinical trial aimed at assessing the therapeutic effects of infiltration vs. sealing for controlling caries progression on proximal surfaces. Out of 90 adult students/patients assessed at university clinics and agreeing to participate, 39, each with 3...... differences in lesion progression between infiltration and placebo (P = 0.0012) and between sealing and placebo (P = 0.0269). The study showed that infiltration and sealing are significantly better than placebo treatment for controlling caries progression on proximal lesions. No significant difference...

  20. Spraying for time - Abradable seals the key

    Science.gov (United States)

    Haines, S. A.

    1984-03-01

    Abradable seals are explained and a brief history of their development is given. Abradable seals are made of high-temperature-resistant composite powders, such as nickel-coated graphite, that constitute a core material coated with metal. They must abrade easily if struck by turbine blades and be soft enough to prevent engine damage should they be blown back. Research done to improve abradable seals with respect to hardness, oxidation, resistance and temperature changes is stressed. The end result is a composite powder with good insulating properties and the ability to withstand temperatures up to 850 C.

  1. [Physiological and biochemical changes of angelica seeds during storage with different moisture contents].

    Science.gov (United States)

    Wang, Yinquan; Zhao, Yong; An, Peikun; Zhang, Jinlin; Wang, Yan

    2012-01-01

    To study the physiological and biochemical changes during storage of angelica seeds with different moisture contents. The dynamic changes of percentage and index of seeds germination, relative conductivity, superoxide dismutase (SOD) activity, contents of soluble sugar and protein were determined at an interval of every two months. Under the conditions stored in sealed paper cups at 15 degrees C for 10 months, the germination percentage of angelica seeds with 2.85% of moisture content was kept above 85%. With moisture content reducing, the increase rate of relative conductivity decreased, the down trend of SOD activity and protein content were weakened, and soluble sugar content kept stable. In cool conditions, a modest low moisture content of seeds can be beneficial to prolong the longevity of angelica seeds, while high moisture content will accelerate the deterioration process of the seeds.

  2. Classification for Tolerance and the Storage to Desiccation Seed Cassia fistula L.

    Directory of Open Access Journals (Sweden)

    F. Pelissari

    2013-03-01

    Full Text Available Abstract: The Knowledge of behavior of seed during storage is essential to maintain their viability for a long time. Therefore, this study aimed to classify the seeds of Cassia fistula on the storage capacity and desiccation-tolerance. The seeds were dried in sealed containers with silica gel to obtain 5% moisture content, and then the germination tests were carried out in Petri dishes with agar, placed in growth chamber at 30 C. Seeds were classified using adapted protocol from Ellis and Hong (1996. The seeds of this species are desiccation-tolerance and can be classified as orthodox, because, even after being placed in low temperature did not lose their viability.Keywords: storage, seed, viability.

  3. The evolution of seeds.

    Science.gov (United States)

    Linkies, Ada; Graeber, Kai; Knight, Charles; Leubner-Metzger, Gerhard

    2010-06-01

    The evolution of the seed represents a remarkable life-history transition for photosynthetic organisms. Here, we review the recent literature and historical understanding of how and why seeds evolved. Answering the 'how' question involves a detailed understanding of the developmental morphology and anatomy of seeds, as well as the genetic programs that determine seed size. We complement this with a special emphasis on the evolution of dormancy, the characteristic of seeds that allows for long 'distance' time travel. Answering the 'why' question involves proposed hypotheses of how natural selection has operated to favor the seed life-history phenomenon. The recent flurry of research describing the comparative biology of seeds is discussed. The review will be divided into sections dealing with: (1) the development and anatomy of seeds; (2) the endosperm; (3) dormancy; (4) early seed-like structures and the transition to seeds; and (5) the evolution of seed size (mass). In many cases, a special distinction is made between angiosperm and gymnosperm seeds. Finally, we make some recommendations for future research in seed biology.

  4. Grape Seed Extract

    Science.gov (United States)

    ... R S T U V W X Y Z Grape Seed Extract Share: On This Page Background How ... Foster This fact sheet provides basic information about grape seed extract—common names, usefulness and safety, and ...

  5. Seeds as biosocial commons

    NARCIS (Netherlands)

    Patnaik, Archana

    2016-01-01

    This research investigates and describes the conservation and use of Plant Genetic Resources (PGRs), especially seeds through processes of commonisation. Seeds form an important element for sustaining human life (through food production) and social relations (by maintaining agricultural

  6. What Are Chia Seeds?

    Science.gov (United States)

    ... your diet? Chia seeds come from the desert plant Salvia hispanica , a member of the mint family. ... ancient Aztec diet. The seeds of a related plant, Salvia columbariae (golden chia), were used primarily by ...

  7. 19 CFR 123.24 - Sealing of conveyances or compartments.

    Science.gov (United States)

    2010-04-01

    ...; DEPARTMENT OF THE TREASURY CUSTOMS RELATIONS WITH CANADA AND MEXICO Shipments in Transit Through Canada or Mexico § 123.24 Sealing of conveyances or compartments. (a) Sealing required. Merchandise in transit...-bound seals may go forward without additional seals. (c) Carrier relieved of responsibility. The port...

  8. Sealing and monitoring a container containing heat generating materials

    International Nuclear Information System (INIS)

    Bourrelly, P.; Monier, J.; Parin, H.; Sanson, C.; Schoepp, R.

    1986-01-01

    The sealing system includes one or several seals on the container wall. These seals comprise resistors electrically connected and thermally insulated for monitoring heat transfer between the seal and the container or the environment by producing an electric signal to a remote monitor. Opening the container changes the heat flux which is detected. Application is made for monitoring radioactive waste containers [fr

  9. The southern elephant seal Mirounga leonina at Gough Island

    African Journals Online (AJOL)

    haul-out in December coincided with the elephant seal moulting season, the elephant seals were found on the vegetated areas whilst the majority of fur seals hauled out onto the boulder beach. No interactions between the two species were recorded. Potential predators of elephant seals, i.e. the killer whales Orcinus orca ...

  10. Application of radioisotope technique for investigation of pumps seals

    International Nuclear Information System (INIS)

    Antoszewski, B.; Zorawska, A.

    1988-01-01

    Radioisotope method of measuring the wear of rings of the face mechanical seals, bush in soft seals, and leakage in double mechanical seals is described. The examples are given. It is found that radioisotope technique can be used for investigation of the seals. (author)

  11. HMSRP Hawaiian Monk Seal Necropsy Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains information on Hawaiian monk seal gross necropsy (in some cases only field notes or minimal information) and histopathology results beginning...

  12. HMSRP Hawaiian Monk Seal Survival Factors

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains records of survival factors recorded by PSD personnel and cooperating scientists as part of the ongoing monk seal population assessment...

  13. HMSRP Hawaiian Monk Seal Microsatellite Genotypes

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Currently ~2,400 Hawaiian monk seal specimens have been analyzed genetically, providing genotypes at 18 microsatellite loci. These data are organized by individual,...

  14. Onboard Acoustic Recording from Diving Elephant Seals

    National Research Council Canada - National Science Library

    Fletcher, Stacia

    1996-01-01

    The aim of this project was to record sounds impinging on free-ranging northern elephant seals, Mirounga angustirostris, a first step in determining the importance of LFS to these animals as they dive...

  15. Cask systems development program seal technology

    International Nuclear Information System (INIS)

    Madsen, M.M.; Humphreys, D.L.; Edwards, K.R.

    1991-01-01

    General design or test performance requirements for radioactive materials (RAM) packages are specified in Title 10 of the US Code of Federal Regulations Part 71 (10 CFR 71). Seals that provide the containment system interface between the packaging body and the closure must function in both high- and low-temperature environments under dynamic and static conditions. Experiments were performed to characterize the performance of several seal materials at low temperatures. Helium leak tests on face seals were used to compare the materials. Materials tested include butyl, neoprene, ethylene propylene, fluorosilicone, silicone, Eypel, Kalrez, Teflon, fluorocarbon, and Teflon/silicone composites. Results show that the seal materials tested, with the exception of silicone S613-60, are not leak tight (1 x 10 -7 std cm 3 /s) at manufacturer low-temperature ratings

  16. Fuel cell cassette with compliant seal

    Science.gov (United States)

    Karl, Haltiner, Jr. J.; Anthony, Derose J.; Klotzbach, Darasack C.; Schneider, Jonathan R.

    2017-11-07

    A fuel cell cassette for forming a fuel cell stack along a fuel cell axis includes a cell retainer, a plate positioned axially to the cell retainer and defining a space axially with the cell retainer, and a fuel cell having an anode layer and a cathode layer separated by an electrolyte layer. The outer perimeter of the fuel cell is positioned in the space between the plate and the cell retainer, thereby retaining the fuel cell and defining a cavity between the cell retainer, the fuel cell, and the plate. The fuel cell cassette also includes a seal disposed within the cavity for sealing the edge of the fuel cell. The seal is compliant at operational temperatures of the fuel cell, thereby allowing lateral expansion and contraction of the fuel cell within the cavity while maintaining sealing at the edge of the fuel cell.

  17. Prevention of Stripping under Chip Seals

    Science.gov (United States)

    2017-10-01

    Eighteen chip-sealed roadways in eight cities and counties in Minnesota were evaluated both in the field (for condition surveys and density tests) and in the laboratory (for permeability, stripping, tensile-strength ratio, asphalt film thickness, and...

  18. Chip seal performance measures : best practices.

    Science.gov (United States)

    2015-03-01

    The Washington State Department of Transportation (WSDOT) has a long history of designing, constructing, : and maintaining chip seal or bituminous surface treatment pavements. However, to date WSDOT has not : developed pavement performance indicators...

  19. Sealing And Filling Cracks In Asphalt Pavements

    Science.gov (United States)

    1999-11-01

    The primary objective of the crack treatment experiment was to determine the most effective and economical materials and methods for conducting crack-sealing and crack-filling operations. Secondary objectives included the identification of performanc...

  20. Management of spent sealed sources in Indonesia

    International Nuclear Information System (INIS)

    Wisnubroto, D.S.

    2002-01-01

    This paper describes the effort of the Center for Development of Radioactive Waste Management (CDRWM) to develop and implement activities in maintaining and improving the safety of spent sealed radiation sources and the security of radioactive materials over their life cycle. There is a wide variety of uses of radiation sources and radioactive materials in Indonesia, while the CDRWM plan to cover all spent radiation sources. Primary consideration is given to sealed radiation sources with relatively high levels of radioactivity which might necessitate interventional measures should control over them be lost. The policy of the Government of Indonesia for spent radiation sources is, whenever possible, spent sealed sources should be returned to the supplier. CDRWM has a general principle that sealed sources should not be removed from their holders, or the holders physically modified (except for Ra-226 needles, smoke detector and lighting preventer). (author)

  1. Inflatable Module Seal Interface Development and Testing

    Data.gov (United States)

    National Aeronautics and Space Administration — Develop a repeatable low permeable sealing interface evaluating O-ring, RTV bond and flowed RTV bond methods. Advanced Bladder materials (ArmorFlex, Nanoclay, etc)...

  2. HMSRP Hawaiian Monk Seal Tag Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains records for all tags applied to Hawaiian monk seals since 1981. These tags were applied by PSD personnel and cooperating scientists as part of...

  3. Rotatable seal assembly. [Patent application; rotating targets

    Science.gov (United States)

    Logan, C.M.; Garibaldi, J.L.

    1980-11-12

    An assembly is provided for rotatably supporting a rotor on a stator so that vacuum chambers in the rotor and stator remain in communication while the chambers are sealed from ambient air, which enables the use of a ball bearing or the like to support most of the weight of the rotor. The apparatus includes a seal device mounted on the rotor to rotate therewith, but shiftable in position on the rotor while being sealed to the rotor as by an O-ring. The seal device has a flat face that is biased towards a flat face on the stator, and pressurized air is pumped between the faces to prevent contact between them while spacing them a small distance apart to avoid the inflow of large amounts of air between the faces and into the vacuum chambers.

  4. Diverse papillomaviruses identified in Weddell seals.

    Science.gov (United States)

    Smeele, Zoe E; Burns, Jennifer M; Van Doorsaler, Koenraad; Fontenele, Rafaela S; Waits, Kara; Stainton, Daisy; Shero, Michelle R; Beltran, Roxanne S; Kirkham, Amy L; Berngartt, Rachel; Kraberger, Simona; Varsani, Arvind

    2018-04-01

    Papillomaviridae is a diverse family of circular, double-stranded DNA (dsDNA) viruses that infect a broad range of mammalian, avian and fish hosts. While papillomaviruses have been characterized most extensively in humans, the study of non-human papillomaviruses has contributed greatly to our understanding of their pathogenicity and evolution. Using high-throughput sequencing approaches, we identified 7 novel papillomaviruses from vaginal swabs collected from 81 adult female Weddell seals (Leptonychotes weddellii) in the Ross Sea of Antarctica between 2014-2017. These seven papillomavirus genomes were amplified from seven individual seals, and six of the seven genomes represented novel species with distinct evolutionary lineages. This highlights the diversity of papillomaviruses among the relatively small number of Weddell seal samples tested. Viruses associated with large vertebrates are poorly studied in Antarctica, and this study adds information about papillomaviruses associated with Weddell seals and contributes to our understanding of the evolutionary history of papillomaviruses.

  5. Multi-Canister overpack sealing configuration

    International Nuclear Information System (INIS)

    SMITH, K.E.

    1998-01-01

    The Spent Nuclear Fuel (SNF) position regarding the Multi-Canister Overpack (MCO) sealing configuration is to initially rely on an American Society of Mechanical Engineers (ASME) Section III Subsection NB code compliant mechanical closure/sealing system to quickly and safely establish and maintain full confinement of radioactive materials prior to and during MCO fuel drying activities. Previous studies have shown the mechanical seal to be the preferred closure method, based on dose, cost, and schedule considerations. The cost and schedule impacts of redesigning the mechanical closure to a welded shield plug do not support changing the closure system. The SNF Project has determined that the combined mechanical/welded closure system meets or exceeds the regulatory requirements to provide redundant seals while accommodating key safety and schedule limitations that are unique to K Basins fuel removal effort

  6. HMSRP Hawaiian Monk Seal Photo Identification Database

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This photo collection contains identification and other images and video of Hawaiian monk seals taken by PSD personnel and cooperating scientists as part of the...

  7. HMSRP Hawaiian Monk Seal Fisheries Interactions data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The data set contains records of all documented hookings and/or entanglements of Hawaiian monk seals with actively fished gear, both commercial and recreational. The...

  8. HMSRP Hawaiian Monk Seals on Social Media

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — As social media platforms develop, they potentially provide valuable information for wildlife researchers and managers. NOAA’s Hawaiian Monk Seal Research Program...

  9. Collyria seals in the Roman Empire.

    Science.gov (United States)

    Perez-Cambrodi, Rafael J; Pinero, David P; Mavrou, Ariadni; Cervino, Alejandro; Brautaset, Rune; Murube del Castillo, Juan

    2013-01-01

    Roman seals associated with collyria (Latin expression for eye drops/washes and lotions for eye maintenance) provide valuable information about eye care in the antiquity. These small, usually stone-made pieces bore engravings with the names of eye doctors and also the collyria used to treat an eye disease. The collyria seals have been found all over the Roman empire and Celtic territories in particular and were usually associated with military camps. In Hispania (Iberian Peninsula), only three collyria seals have been found. These findings speak about eye care in this ancient Roman province as well as about of the life of the time. This article takes a look at the utility and social significance of the collyria seals and seeks to give an insight in the ophthalmological practice of in the Roman Empire.

  10. HMSRP Hawaiian Monk Seal Survey Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains records of Hawaiian monk seal and green turtle sightings in the Northwestern Hawaiian Islands (NWHI) since 1982 at Lisianski Island, and since...

  11. Tamper-indicating devices and safeguards seals evaluation test report

    International Nuclear Information System (INIS)

    Horton, P.R.V.; Waddoups, I.G.

    1993-12-01

    Sandia National Laboratories was asked to evaluate the seals used as tamper-indicating devices (TIDs) at DOE facilities. Initially, a survey determined what seal manufacturers were being used and what similar seal types were available. Once the required specifications for TIDs were defined, a test plan measured the currently available seals against the requirements. Environmental and physical type tests stressed the seals under two broad categories: (1) handling durability and (2) tamper resistance. Results of the testing provide comparative ratings for the various seals, recommendations for using currently available seals, and a new tamper-indicating technology

  12. Troubleshooting ProSeal LMA

    Directory of Open Access Journals (Sweden)

    Bimla Sharma

    2009-01-01

    Full Text Available Supraglottic devices have changed the face of the airway management. These devices have contributed in a big way in airway management especially, in the difficult airway scenario significantly decreasing the pharyngolaryngeal morbidity. There is a plethora of these devices, which has been well matched by their wider acceptance in clinical practice. ProSeal laryngeal mask airway (PLMA is one such frequently used device employed for spontaneous as well as controlled ventilation. However, the use of PLMAat tunes maybe associated with certain problems. Some of the problems related with its use are unique while others are akin to the classic laryngeal mask airway (eLMA. However, expertise is needed for its safe and judicious use, correct placement, recognition and management of its various malpositions and complications. The present article describes the tests employed for proper confirmation of placementto assess the ventilatooy and the drain tube functions of the mask, diagnosis of various malpositions and the management of these aspects. All these areas have been highlighted under the heading of troubleshooting PLMA. Many problems can be solved by proper patient and procedure selection, maintaining adequate depth of anaesthesia, diagnosis and management of malpositions. Proper fixation of the device and monitoring cuff pressure intraopera-tively may bring down the incidence of airway morbidity.

  13. Simulation of leakage through mechanical sealing device

    Science.gov (United States)

    Tikhomorov, V. P.; Gorlenko, O. A.; Izmerov, M. A.

    2018-03-01

    The procedure of mathematical modeling of leakage through the mechanical seal taking into account waviness and roughness is considered. The percolation process is represented as the sum of leakages through a gap between wavy surfaces and percolation through gaps formed by fractal roughness, i.e. the total leakage is determined by the slot model and filtration leakage. Dependences of leaks on the contact pressure of corrugated and rough surfaces of the mechanical seal elements are presented.

  14. Mechanical seal having a double-tier mating ring

    Science.gov (United States)

    Khonsari, Michael M.; Somanchi, Anoop K.

    2005-09-13

    An apparatus and method to enhance the overall performance of mechanical seals in one of the following ways: by reducing seal face wear, by reducing the contact surface temperature, or by increasing the life span of mechanical seals. The apparatus is a mechanical seal (e.g., single mechanical seals, double mechanical seals, tandem mechanical seals, bellows, pusher mechanical seals, and all types of rotating and reciprocating machines) comprising a rotating ring and a double-tier mating ring. In a preferred embodiment, the double-tier mating ring comprises a first and a second stationary ring that together form an agitation-inducing, guided flow channel to allow for the removal of heat generated at the seal face of the mating ring by channeling a coolant entering the mating ring to a position adjacent to and in close proximity with the interior surface area of the seal face of the mating ring.

  15. on oil palm seeds

    African Journals Online (AJOL)

    User

    The ab- dominal sternite is cream-white. The femur of the hind leg is thick. The compound eyes are black. This study showed that the larvae developed within the shells, on surface of the seeds, rotten. Infestation by Megaselia rufipes Meigen on germinated oil palm seeds ... 29. Fig. 5: Cracked seeds infested with maggots.

  16. Seed development and carbohydrates

    NARCIS (Netherlands)

    Wittich, P.E.

    1998-01-01

    Seeds assure the plant the onset of a next generation and a way of dispersal. They consist of endosperm and an embryo (originating from gametophytic tissue), enveloped by a seed coat (sporophytic tissue). Plants generate different types of seeds. For instance, the endosperm may either be

  17. Behaviour of elastomeric seals at low temperature

    International Nuclear Information System (INIS)

    Weise, H.P.; Kowalewsky, H.; Wenz, R.

    1993-01-01

    The properties of elastomer O-ring seals (Viton, silicone rubber, EPDM) at low temperature have been investigated by measuring the gas leakage rate and the sealing force during thermal cycling between +20degC and -70degC. For all materials it has been found that at a well defined (critical) temperature the leakage rate sharply rises from permeation level to a high value which is determined by gas streaming through the leak path between the O-ring and the flange surfaces arising from thermal contraction of the elastomer in the glassy state. At the critical temperature the sealing force has been found to be zero or even negative due to adhesion between the elastomer material and the flanges. For all seals the critical temperature is well below the glass transition of the elastomer and also significantly below the temperature where the compression set becomes 100 %. Warming up the sealing system restores leak tightness. Low temperature cycle of elastomeric seals have been found to be entirely reversible. (author)

  18. Self-balancing air riding seal for a turbine

    Energy Technology Data Exchange (ETDEWEB)

    Mills, Jacob A.

    2017-08-15

    A turbine of a gas turbine engine has an air riding seal that forms a seal between a rotor and a stator of the turbine, the air riding seal including an annular piston movable in an axial direction under the influence of a pressure on one side with a pressure acting on an opposite side that self-balances the air riding seal during the steady state condition of the engine and lifts off the seal during engine transients.

  19. Seroprevalence of Antibodies against Seal Influenza A(H10N7) Virus in Harbor Seals and Gray Seals from the Netherlands.

    Science.gov (United States)

    Bodewes, Rogier; Rubio García, Ana; Brasseur, Sophie M; Sanchez Conteras, Guillermo J; van de Bildt, Marco W G; Koopmans, Marion P G; Osterhaus, Albert D M E; Kuiken, Thijs

    2015-01-01

    In the spring and summer 2014, an outbreak of seal influenza A(H10N7) virus infection occurred among harbor seals (Phoca vitulina) off the coasts of Sweden and Denmark. This virus subsequently spread to harbor seals off the coasts of Germany and the Netherlands. While thousands of seals were reported dead in Sweden, Denmark and Germany, only a limited number of seals were found dead in the Netherlands. To determine the extent of exposure of seals in the Netherlands to influenza A/H10N7 virus, we measured specific antibody titers in serum samples from live-captured seals and seals admitted for rehabilitation in the Netherlands by use of a hemagglutination inhibition assay and an ELISA. In harbor seals in 2015, antibodies against seal influenza A(H10N7) virus were detected in 41% (32 out of 78) pups, 10% (5 out of 52) weaners, and 58% (7 out of 12) subadults or adults. In gray seals (Halichoerus grypus) in 2015, specific antibodies were not found in the pups (n = 26), but in 26% (5 out of 19) of the older animals. These findings indicate that, despite apparent low mortality, infection with seal influenza A(H10N7) virus was geographically widespread and also occurred in grey seals.

  20. Development of procedure using plasma welding process to produce 125I seeds

    International Nuclear Information System (INIS)

    Feher, Anselmo

    2006-01-01

    The prostate cancer, which is the second cause of death by cancer in men, overcome only by lung cancer, is a problem of public health in Brazil. Brachytherapy is among the possible available treatments for prostate cancer, in which small seeds containing 125 I radioisotope are implanted in the prostate. The seed consists of a titanium sealed capsule with 0.8 mm external diameter and 4.5 mm length, containing a central silver wire with adsorbed 125 I. The plasma arc welding is one of the viable techniques for the sealing process. The equipment used in this technique is less costly than in other processes. The main objective of this work was the development and the validation of the welding procedure using plasma welding process and the elaboration of a sealing routine according to Good Manufacturing Practices. The development of this work has presented the following phases: cut and cleaning of the titanium material, determination of the welding parameters, development of a device for holding the titanium tube during the welding process, validation of sealed sources according to ISO 2919 Sealed Radioactive Sources - General Requirements and Classification, leakage test according to ISO 9978 Sealed Radioactive Sources - Leakage Test Methods and metallographic assays. The developed procedure, to seal 125 I seeds using plasma welding process, has shown to be efficient, satisfying all the established requirements of ISO 2919. The results obtained in this work have given the possibility to establish a routine production process according to the orientations presented in resolution RDC number 59 - Good Manufacturing Practices do Medical Products of the ANVISA - Brazilian Nacional Agency of Sanitary Surveillance. (author)

  1. DEVELOPMENT OF A CERAMIC TAMPER INDICATING SEAL: SRNL CONTRIBUTIONS

    Energy Technology Data Exchange (ETDEWEB)

    Krementz, D.; Brinkman, K.; Martinez-Rodriguez, M.; Mendez-Torres, A.; Weeks, G.

    2013-06-03

    Savannah River National Laboratory (SRNL) and Sandia National Laboratories (SNL) are collaborating on development of a Ceramic Seal, also sometimes designated the Intrinsically Tamper Indicating Ceramic Seal (ITICS), which is a tamper indicating seal for international safeguards applications. The Ceramic Seal is designed to be a replacement for metal loop seals that are currently used by the IAEA and other safeguards organizations. The Ceramic Seal has numerous features that enhance the security of the seal, including a frangible ceramic body, protective and tamper indicating coatings, an intrinsic unique identifier using Laser Surface Authentication, electronics incorporated into the seal that provide cryptographic seal authentication, and user-friendly seal wire capture. A second generation prototype of the seal is currently under development whose seal body is of Low Temperature Co-fired Ceramic (LTCC) construction. SRNL has developed the mechanical design of the seal in an iterative process incorporating comments from the SNL vulnerability review team. SRNL is developing fluorescent tamper indicating coatings, with recent development focusing on optimizing the durability of the coatings and working with a vendor to develop a method to apply coatings on a 3-D surface. SRNL performed a study on the effects of radiation on the electronics of the seal and possible radiation shielding techniques to minimize the effects. SRNL is also investigating implementation of Laser Surface Authentication (LSA) as a means of unique identification of each seal and the effects of the surface coatings on the LSA signature.

  2. Gas-lubricated seal for sealing between a piston and a cylinder wall

    Science.gov (United States)

    Hoult, D.P.

    1985-09-10

    A piston-cylinder seal uses gas for a lubricant and has a runner supported on a gapless structure and placed in the space between the piston and the cylinder wall. The runner is deformed elastically under the influence of the operating pressures to follow and compensate for variations in the piston-cylinder fit and maintain a seal. 4 figs.

  3. Development of a Whole Container Seal

    Energy Technology Data Exchange (ETDEWEB)

    Kuhn, Michael J [ORNL; Pickett, Chris A [ORNL; Stinson, Brad J [ORNL; Rowe, Nathan C [ORNL

    2014-01-01

    This paper outlines a technique for utilizing electrically conductive textiles as a whole container seal. This method has the potential to provide more robustness for ensuring that the container has not been breached versus conventional sealing methods that only provide tamper indication at the area used for normal access. The conductive textile is used as a distributed sensor for detecting and localizing container tamper or breach. For sealing purposes, the conductive fabric represents a bounded, near-infinite grid of resistors. The well-known infinite resistance grid problem was used to model and confirm the expected accuracy and validity of this approach. An experimental setup was built that uses a multiplexed Wheatstone bridge measurement to determine the resistances of a coarse electrode grid across the conductive fabric. Non-uniform resistance values of the grid infer the presence of damage or tears in the fabric. Results suggest accuracy proportional to the electrode spacing in determining the presence and location of disturbances in conductive fabric samples. Current work is focused on constructing experimental prototypes for field and environmental testing to gauge the performance of these whole container seals in real world conditions. We are also developing software and hardware to interface with the whole container seals. The latest prototypes are expected to provide more accuracy in detecting and localizing events, although detection of a penetration should be adequate for most sealing applications. We are also developing smart sensing nodes that integrate digital hardware and additional sensors (e.g., motion, humidity) into the electrode nodes within the whole container seal.

  4. Materials for water pump mechanical seals

    International Nuclear Information System (INIS)

    Brousse, P.

    1992-01-01

    In view of the continually increasing power ratings of conventional and nuclear power plants and the related reliability and safety problems, plant builders have had to develop seal systems compatible with current water pump performances. In 1970, EDF/R and DD was already concerned by this problem. It soon became obvious that the nature of the materials used for the friction surfaces was decisive for seal durability. Exceptional loads (transients, high vibration levels, etc...) hasten aging. To begin with, friction surfaces consisted of a hard material (tungsten carbide) mated with a soft material (carbon). Resistance was unpredictable and not compatible with industrial requirements. Tests performed on the EDF/R and DD test benches evidenced the same types of degradation. The mechanical seal manufacturers then began to use ceramic materials (silicon carbide), which raised high expectations. Unfortunately, these were recent materials and their manufacturing process was not thoroughly understood. Hopes were soon dashed in many applications, including that of mechanical seals. Fluctuating results were obtained over the next few years. The raw material suppliers made progress, especially with regard to reducing fragility. On a parallel, the mechanical seal manufacturers initiated comparative tests on the friction resistance of materials. It has also been established that ceramics have to be stringently supervised at all levels: part design, inspection, assembly, use. EDF has much insisted that mechanical seal suppliers guarantee the constant quality of their products. EDF/R and DD has systematically tested new sensitive devices, under normal and exceptional conditions, prior to their installation at the plants. At the present time, the silicon carbides proposed by the mechanical seal suppliers are entirely satisfactory. The carbon mating surface was far less problematic. The required reliability was obtained by replacing resin binder carbons by the more resistant

  5. Study and development of an Iridium-192 seed for use in ophthalmic cancer

    International Nuclear Information System (INIS)

    Mattos, Fabio Rodrigues de

    2013-01-01

    Even ocular tumors are not among the cases with a higher incidence, they affect the population, especially children. The Institute of Energy and Nuclear Research (IPEN-CNEN/SP) in partnership with Escola Paulista de Medicina (UNIFESP), created a project to develop and implement a alternative treatment for ophthalmic cancer that use brachytherapy iridium-192 seeds. The project arose by reason of the Escola Paulista treat many cancer cases within the Unified Health System (SUS) and the research experience of sealed radioactive sources group at IPEN. The methodology was developed from the available infrastructure and the experience of researchers. The prototype seed presents with a core (192-iridium alloy of iridium-platinum) of 3.0 mm long sealed by a capsule of titanium of 0.8 mm outside diameter, 0.05 mm wall thickness and 4,5mm long. This work aims to study and develop a seed of iridium-192 from a platinum-iridium alloy. No study on the fabrication of these seeds was found in available literature. It was created a methodology that involved: characterization of the material used in the core, creation of device for neutron activation irradiation and and seed sealing tests. As a result, proved the feasibility of the method. As a suggestion for future work, studies regarding metrology and dosimetry of these sources and improvement of the methodology should be carried out, for future implementation in national scope. (author)

  6. Solid oxide fuel cell having a glass composite seal

    Science.gov (United States)

    De Rose, Anthony J.; Mukerjee, Subhasish; Haltiner, Jr., Karl Jacob

    2013-04-16

    A solid oxide fuel cell stack having a plurality of cassettes and a glass composite seal disposed between the sealing surfaces of adjacent cassettes, thereby joining the cassettes and providing a hermetic seal therebetween. The glass composite seal includes an alkaline earth aluminosilicate (AEAS) glass disposed about a viscous glass such that the AEAS glass retains the viscous glass in a predetermined position between the first and second sealing surfaces. The AEAS glass provides geometric stability to the glass composite seal to maintain the proper distance between the adjacent cassettes while the viscous glass provides for a compliant and self-healing seal. The glass composite seal may include fibers, powders, and/or beads of zirconium oxide, aluminum oxide, yttria-stabilized zirconia (YSZ), or mixtures thereof, to enhance the desirable properties of the glass composite seal.

  7. Method and system to facilitate sealing in gas turbines

    Science.gov (United States)

    Morgan, Victor John; Foster, Gregory Thomas; Sarawate, Neelesh Nandkumar

    2017-09-12

    A method and system for sealing between components within a gas turbine is provided. A first recess defined in a first component receives a seal member. A second recess defined in a second component adjacent the first component also receives the seal member. The first and second recesses are located proximate a hot gas path defined through the gas turbine, and define circumferential paths about the turbine axis. The seal member includes a sealing face that extends in a direction substantially parallel to the turbine axis. The seal member also includes a plurality of seal layers, wherein at least one of the seal layers includes at least one stress relief region for facilitating flexing of the first seal member.

  8. Advanced Seal Development for Large Industrial Gas Turbines

    Science.gov (United States)

    Chupp, Raymond E.

    2006-01-01

    Efforts are in progress to develop advanced sealing for large utility industrial gas turbine engines (combustion turbines). Such seals have been under developed for some time for aero gas turbines. It is desired to transition this technology to combustion turbines. Brush seals, film riding face and circumferential seals, and other dynamic and static sealing approaches are being incorporated into gas turbines for aero applications by several engine manufacturers. These seals replace labyrinth or other seals with significantly reduced leakage rates. For utility industrial gas turbines, leakage reduction with advanced sealing can be even greater with the enormous size of the components. Challenges to transitioning technology include: extremely long operating times between overhauls; infrequent but large radial and axial excursions; difficulty in coating larger components; and maintenance, installation, and durability requirements. Advanced sealing is part of the Advanced Turbine Systems (ATS) engine development being done under a cooperative agreement between Westinghouse and the US Department of Energy, Office of Fossil Energy. Seal development focuses on various types of seals in the 501ATS engine both at dynamic and static locations. Each development includes rig testing of candidate designs and subsequent engine validation testing of prototype seals. This presentation gives an update of the ongoing ATS sealing efforts with special emphasis on brush seals.

  9. Plasma treatment of Seeds: effect on growth, spores and bacterial charge

    Science.gov (United States)

    Ambrico, P. F.; Simek, M.; Morano, M.; Ambrico, M.; Minafra, A.; Prukner, V.; de Miccolis Angelini, R. M.; Trotti, P.

    2016-09-01

    We report on the effect of low temperature plasma treatment on tomato, basil and tobacco commercial seeds. Seeds were treated in filtered ambient air volume, surface and plasma jet DBD at atmospheric pressure Sterile agar substrate, supplemented with a nutrient and vitamin mixture, was used to allow seeds germination in sterilized sealed plastic containers. The seeds were stored in controlled environmental condition (T = 26C, cycle of 14hrs light/10hrs dark condition). Since all the procedure was performed under sterile conditions, only bacteria and fungi carried by seeds could grow. Plasma treatment significantly reduced the presence of bacterial contamination, while some fungi could resist at shortest exposures Seeds germination was then followed by time lapse photography in sterile water on 3MM Whatman paper in a closed container. The effect of plasma treatment was a faster germination time of seeds and emergence of cotyledons, able to start photosynthesis in seedlings.The plasma treated seeds were also sow in a soil/peat moss mixture. Plants were cultivated for about 40 days, showing that plasma induced a faster growth in length and weight with respect to untreated seeds.Furthermore the effect of plasma on seeds surface was studied by SEM imaging. We acknowledge `SELGE' (Puglia) and TACR (TA03010098).

  10. Design Vulnerability Assessments for Safeguards Sealing Systems

    International Nuclear Information System (INIS)

    Brockman, Linda; Johnston, Roger; Kravtchenko, Victor; Undem, Halvor A.; Wishard, Bernard

    2010-01-01

    The International Atomic Energy Agency (the 'Agency') engages in a rigorous equipment authorization process prior to deploying Safeguards instrumentation, including Safeguards sealing systems, for world-wide use. A positive result from a vulnerability assessment is one of the many requirements that must be met prior to instrumentation deployment. Given the long time period in the Safeguards instrumentation development cycle, the substantial Member State investments made, and the significant Agency staff time required, a negative result for the vulnerability assessment can result in the loss of time, considerable additional expense, or even the failure to deploy an instrument or sealing system at all. First suggested in 1998 by the General Physics Institute in Moscow, an approach that incorporates a design vulnerability assessment minimizes the risk of deployment failure by teaming a public sector vulnerability assessment team with the instrument or sealing system design team in order to identify, at the earliest possible design stage, inherent vulnerabilities. Involving the vulnerability assessors early and often in the design and development process avoids many of the problems inherent in evaluating security vulnerabilities only after the design is finalized. The disadvantages include increased costs and time to deployment. An improved pressure-sensitive adhesive label seal, called the 'VOID-3 seal' was developed for the Agency using this design vulnerability assessment process.

  11. Modeling the rubbing contact in honeycomb seals

    Science.gov (United States)

    Fischer, Tim; Welzenbach, Sarah; Meier, Felix; Werner, Ewald; kyzy, Sonun Ulan; Munz, Oliver

    2018-03-01

    Metallic honeycomb labyrinth seals are commonly used as sealing systems in gas turbine engines. Because of their capability to withstand high thermo-mechanical loads and oxidation, polycrystalline nickel-based superalloys, such as Hastelloy X and Haynes 214, are used as sealing material. In addition, these materials must exhibit a tolerance against rubbing between the rotating part and the stationary seal component. The tolerance of the sealing material against rubbing preserves the integrity of the rotating part. In this article, the rubbing behavior at the rotor-stator interface is considered numerically. A simulation model is incorporated into the commercial finite element code ABAQUS/explicit and is utilized to simulate a simplified rubbing process. A user-defined interaction routine between the contact surfaces accounts for the thermal and mechanical interfacial behavior. Furthermore, an elasto-plastic constitutive material law captures the extreme temperature conditions and the damage behavior of the alloys. To validate the model, representative quantities of the rubbing process are determined and compared with experimental data from the literature. The simulation results correctly reproduce the observations made on a test rig with a reference stainless steel material (AISI 304). A parametric study using the nickel-based superalloys reveals a clear dependency of the rubbing behavior on the sliding and incursion velocity. Compared to each other, the two superalloys studied exhibit a different rubbing behavior.

  12. Modeling the rubbing contact in honeycomb seals

    Science.gov (United States)

    Fischer, Tim; Welzenbach, Sarah; Meier, Felix; Werner, Ewald; kyzy, Sonun Ulan; Munz, Oliver

    2017-12-01

    Metallic honeycomb labyrinth seals are commonly used as sealing systems in gas turbine engines. Because of their capability to withstand high thermo-mechanical loads and oxidation, polycrystalline nickel-based superalloys, such as Hastelloy X and Haynes 214, are used as sealing material. In addition, these materials must exhibit a tolerance against rubbing between the rotating part and the stationary seal component. The tolerance of the sealing material against rubbing preserves the integrity of the rotating part. In this article, the rubbing behavior at the rotor-stator interface is considered numerically. A simulation model is incorporated into the commercial finite element code ABAQUS/explicit and is utilized to simulate a simplified rubbing process. A user-defined interaction routine between the contact surfaces accounts for the thermal and mechanical interfacial behavior. Furthermore, an elasto-plastic constitutive material law captures the extreme temperature conditions and the damage behavior of the alloys. To validate the model, representative quantities of the rubbing process are determined and compared with experimental data from the literature. The simulation results correctly reproduce the observations made on a test rig with a reference stainless steel material (AISI 304). A parametric study using the nickel-based superalloys reveals a clear dependency of the rubbing behavior on the sliding and incursion velocity. Compared to each other, the two superalloys studied exhibit a different rubbing behavior.

  13. Tribological Studies of Dynamic Thermal Seal Materials

    Science.gov (United States)

    DeMange, Jeffrey J.; Taylor, Shawn C.

    2016-01-01

    Thermal seals are required on high-speed vehicles in many dynamic applications such as variable inlets in propulsion systems and control surfaces. These seals, often referred to as dynamic thermal seals, must not only mitigate inboard heat transfer, but must also exhibit sufficient durability when scrubbed against mating surfaces. For high-temperature high-speed vehicle applications, the mating surfaces are often made from thermal protection system (TPS) materials, which are typically rougher and more abrasive than TPS materials used at lower temperatures. The high-temperature TPS materials used can include non-ablative (e.g., lightweight porous oxides, ceramic matrix composites) andor ablative systems (e.g., phenolic systems). Due to the increased need for durable high-temperature dynamic seals, researchers working with the NASA Glenn Research Center embarked on an effort to (a) characterize the tribological performance of state-of-the-art thermal seal materials against a variety of TPS materials and (b) develop approaches for improved wear resistance. Tests were conducted using a recently upgraded high-temperature tribometer to assess wear resistance for a variety of tribopairs under multiple conditions. This data will begin to frame the challenges of using these materials and eventually permit an improved ability to design and implement these critical TPS components.

  14. Does the informal seed system threaten cowpea seed health?

    NARCIS (Netherlands)

    Biemond, P.C.; Oguntade, O.; Lava Kumar, P.; Stomph, T.J.; Termorshuizen, A.J.; Struik, P.C.

    2013-01-01

    Most smallholder farmers in developing countries depend on an informal Seed System (SS) for their seed. The informal SS is often criticized because farmer-produced seed samples are not tested for seed health, thus accepting the risk of planting infected seeds. Here we aimed at assessing the quality

  15. Seal assembly with anti-rotation pin for high pressure supercritical fluids

    Science.gov (United States)

    Wright, Steven A.; Fuller, Robert L.

    2014-08-05

    A seal assembly for sealing a machine with a first chamber and a second chamber is provided. A rotating shaft extends through the first and second chambers, and rotates therein. The seal assembly has a seal housing, a seal ring and a seal pin. The seal housing is positionable in the machine housing. The seal housing has a seal pocket extending into a fluid side thereof, and a housing receptacle extending into an inner diameter thereof at the seal pocket. The seal ring is positionable in the seal pocket of the seal housing for forming a seal therewith. The seal ring has a ring receptacle extending into an outer diameter thereof. The ring receptacle is positionable adjacent to the housing receptacle for defining a pin hole therebetween. The seal pin is loosely positionable in the pin hole whereby movement about the seal ring is accommodated while preventing rotation thereof.

  16. LM2500+ Brush Seal Case Study

    Science.gov (United States)

    Haaser, Fred G.

    2006-01-01

    The LM2500+ industrial aeroderivative gas turbine, a 25% enhanced power derivative of the LM2500 gas turbine, recently completed its development test program during the period 5/96 - 10/96. Early in the engine program a Quality Function Deployment (QFD) process was used to determine customer needs for this project.The feedback obtained from the QFD process showed without doubt that gas turbine customers now emphasize product reliability and availability at the top of their needs. One area of development on the LM2500+ was to investigate the use of a brush seal as a means to reduce undesirable turbine cooling leakages within the turbine mid frame in order to enhance part life. This presentation presents a case study on the factors that went into evaluating a brush seal during engine test, test results, and the ultimate decision not to implement the brush seal for cost and other reasons.

  17. Sealed sources in Peru: advances and outlook

    International Nuclear Information System (INIS)

    Rodriguez, C.G.

    1998-01-01

    Cementation of spent sealed sources is performed by the Radioactive Waste Management Group of the Peruvian Institute of Nuclear Energy (IPEN). The sealed sources are collected in different areas of the country and brought to the RACSO nuclear centre, a national storage and conditioning facility for spent sources from industry and medical institutions. In addition to its amenities dedicated to research and the production of radioisotopes, the RACSO nuclear centre features a complex of some 1.5 ha for radioactive waste management that includes an infiltration bed and chemical treatment plant for liquid waste, compacting equipment and trenches for solid radioactive waste, a tank for the elimination of biological residues and a temporary storage emplacement for radioactive waste immobilized in cement cylinder casings. The steps described are the unpacking, identification of spent sealed sources, placement of the source in shielding, cementation, solidification, tagging and storage, as well as the actions taken to comply with the appropriate measures of radiological protection. (author)

  18. A comparison of the flow of iodine 125 through three different intestinal anastomoses: standard, Gambee, and stapler

    International Nuclear Information System (INIS)

    Wheeless, C.R. Jr.; Smith, J.J.

    1983-01-01

    Angiogenesis determines blood supply, and it is postulated that after surgery, the healing of a wound is directly related to the blood supplied to the surrounding tissues. As a first step in evaluating the process of flow through different surgical anastomoses, the flow rate of 125 I through three different types of anastomoses in the intestines of dogs was determined. When the results were compared, the flow rate through the stapler anastomosis was significantly higher than the flow rate through the standard and Gambee anastomoses

  19. DNA-PKcs Expression Is a Predictor of Biochemical Recurrence After Permanent Iodine 125 Interstitial Brachytherapy for Prostate Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Molina, Sarah [Department of Pathology, INSERM UMR1069, CHU/Université de Tours, Tours (France); Department of Radiation Oncology, CHU/Université de Poitiers, Poitiers (France); Guerif, Stéphane; Garcia, Alexandre [Department of Radiation Oncology, CHU/Université de Poitiers, Poitiers (France); Debiais, Céline [Department of Pathology, CHU/Université de Poitiers, Poitiers (France); Irani, Jacques [Department of Urology, CHU/Université de Poitiers, Poitiers (France); Fromont, Gaëlle, E-mail: gaelle.fromont-hankard@univ-tours.fr [Department of Pathology, INSERM UMR1069, CHU/Université de Tours, Tours (France)

    2016-07-01

    Purpose: Predictive factors for biochemical recurrence (BCR) in localized prostate cancer (PCa) after brachytherapy are insufficient to date. Cellular radiosensitivity depends on DNA double-strand breaks, mainly repaired by the nonhomologous end-joining (NHEJ) system. We analyzed whether the expression of NHEJ proteins can predict BCR in patients treated by brachytherapy for localized PCa. Methods and Materials: From 983 PCa cases treated by brachytherapy between March 2000 and March 2012, 167 patients with available biopsy material suitable for in situ analysis were included in the study. The median follow-up time was 47 months. Twenty-nine patients experienced BCR. All slides were reviewed to reassess the Gleason score. Expression of the key NHEJ proteins DNA-PKcs, Ku70, and Ku80, and the proliferation marker Ki67, was studied by immunohistochemistry performed on tissue microarrays. Results: The Gleason scores after review (P=.06) tended to be associated with BCR when compared with the score initially reported (P=.74). Both the clinical stage (P=.02) and the pretreatment prostate-specific antigen level (P=.01) were associated with biochemical failure. Whereas the expression of Ku80 and Ki67 were not predictive of relapse, positive DNA-PKcs nuclear staining (P=.003) and higher Ku70 expression (P=.05) were associated with BCR. On multivariate analysis, among pretreatment variables, only DNA-PKcs (P=.03) and clinical stage (P=.02) remained predictive of recurrence. None of the patients without palpable PCa and negative DNA-PKcs expression experienced biochemical failure, compared with 32% of men with palpable and positive DNA-PKcs staining that recurred. Conclusions: Our results suggest that DNA-PKcs could be a predictive marker of BCR after brachytherapy, and this might be a useful tool for optimizing the choice of treatment in low-risk PCa patients.

  20. Evolution of dosimetry constraints to reduce the acute urinary toxicity after prostate brachytherapy with iodine 125 of 395 localised cancers

    International Nuclear Information System (INIS)

    Guerif, S.; Bonvalet, L.; Goudona, J.B.; Glandier, C.

    2007-01-01

    The incidence reduction of urethritis and its length are correlated with a reduction of the urethral D90 and D30 on our selection. The future progress will pass through a targeted therapy on a macroscopic tumoral volume by keeping the V100 to reduce the urethral D90 and the D30. We study now, the possibility to boost the macroscopic tumoral volume seen on MRI with a coverage one V100 between 145 and 150 Gy, a D90 inferior to 160 Gy and an minimal urethral D30. (N.C.)

  1. Uveal Melanoma Treated With Iodine-125 Episcleral Plaque: An Analysis of Dose on Disease Control and Visual Outcomes

    Energy Technology Data Exchange (ETDEWEB)

    Perez, Bradford A. [Department of Radiation Oncology, Duke University, Durham, North Carolina (United States); Mettu, Pradeep; Vajzovic, Lejla [Department of Ophthalmology, Duke University, Durham, North Carolina (United States); Rivera, Douglas [Austin Cancer Centers, Austin, Texas (United States); Alkaissi, Ali; Steffey, Beverly A.; Cai, Jing [Department of Radiation Oncology, Duke University, Durham, North Carolina (United States); Stinnett, Sandra [Department of Biostatistics and Informatics, Duke University, Durham, North Carolina (United States); Dutton, Jonathan J. [Department of Ophthalmology, University of North Carolina, Chapel Hill, North Carolina (United States); Buckley, Edward G. [Department of Ophthalmology, Duke University, Durham, North Carolina (United States); Halperin, Edward [Department of Radiation Oncology, New York Medical College, Valhalla, New York (United States); Marks, Lawrence B. [Department of Radiation Oncology, University of North Carolina, Chapel Hill, North Carolina (United States); Mruthyunjaya, Prithvi [Department of Radiation Oncology, Duke University, Durham, North Carolina (United States); Department of Ophthalmology, Duke University, Durham, North Carolina (United States); Kirsch, David G., E-mail: david.kirsch@duke.edu [Department of Radiation Oncology, Duke University, Durham, North Carolina (United States); Department of Pharmacology and Cancer Biology, Duke University, Durham, North Carolina (United States)

    2014-05-01

    Purpose: To investigate, in the treatment of uveal melanomas, how tumor control, radiation toxicity, and visual outcomes are affected by the radiation dose at the tumor apex. Methods and Materials: A retrospective review was performed to evaluate patients treated for uveal melanoma with {sup 125}I plaques between 1988 and 2010. Radiation dose is reported as dose to tumor apex and dose to 5 mm. Primary endpoints included time to local failure, distant failure, and death. Secondary endpoints included eye preservation, visual acuity, and radiation-related complications. Univariate and multivariate analyses were performed to determine associations between radiation dose and the endpoint variables. Results: One hundred ninety patients with sufficient data to evaluate the endpoints were included. The 5-year local control rate was 91%. The 5-year distant metastases rate was 10%. The 5-year overall survival rate was 84%. There were no differences in outcome (local control, distant metastases, overall survival) when dose was stratified by apex dose quartile (<69 Gy, 69-81 Gy, 81-89 Gy, >89 Gy). However, increasing apex dose and dose to 5-mm depth were correlated with greater visual acuity loss (P=.02, P=.0006), worse final visual acuity (P=.02, P<.0001), and radiation complications (P<.0001, P=.0009). In addition, enucleation rates were worse with increasing quartiles of dose to 5 mm (P=.0001). Conclusions: Doses at least as low as 69 Gy prescribed to the tumor apex achieve rates of local control, distant metastasis–free survival, and overall survival that are similar to radiation doses of 85 Gy to the tumor apex, but with improved visual outcomes.

  2. Correlation of cytotoxicity with elimination of iodine-125 from nude mice inoculated with prelabeled human melanoma cells

    International Nuclear Information System (INIS)

    Lockshin, A.; Giovanella, B.C.; Quian, C.; Mendoza, J.T.; Vardeman, D.M.; Stehlin, J.S. Jr.

    1984-01-01

    BRO human melanoma cells were prelabeled in vitro with [125I]5-iodo-2'-deoxyuridine ([125I]IdUrd) and inoculated into NIH-II nude mice ip, im, sc, or iv. Saline or diphtheria toxin (DT), which is selectively toxic to human cells compared to those of mice, was injected, and the loss of 125I from the animals was monitored daily with a whole-body gamma scintillation detector. For most of the inoculation sites DT accelerated the rate of 125I excretion and in all cases was cytotoxic for the inoculated cells as determined by host survival or measurement of visible tumor growth. Differences between the rates of 125I loss for DT-treated mice compared to untreated mice were most evident for cells inoculated ip or im. These results indicate that [125I]IdUrd prelabeling of human tumor cells inoculated in nude mice offers a rapid method for determination of cytotoxicity in vivo

  3. Iodine 125-lysergic acid diethylamide binds to a novel serotonergic site on rat choroid plexus epithelial cells

    International Nuclear Information System (INIS)

    Yagaloff, K.A.; Hartig, P.R.

    1985-01-01

    125 I-Lysergic acid diethylamide ( 125 I-LSD) binds with high affinity to serotonergic sites on rat choroid plexus. These sites were localized to choroid plexus epithelial cells by use of a novel high resolution stripping film technique for light microscopic autoradiography. In membrane preparations from rat choroid plexus, the serotonergic site density was 3100 fmol/mg of protein, which is 10-fold higher than the density of any other serotonergic site in brain homogenates. The choroid plexus site exhibits a novel pharmacology that does not match the properties of 5-hydroxytryptamine-1a (5-HT1a), 5-HT1b, or 5-HT2 serotonergic sites. 125 I-LSD binding to the choroid plexus site is potently inhibited by mianserin, serotonin, and (+)-LSD. Other serotonergic, dopaminergic, and adrenergic agonists and antagonists exhibit moderate to weak affinities for this site. The rat choroid plexus 125 I-LSD binding site appears to represent a new type of serotonergic site which is located on non-neuronal cells in this tissue

  4. Complex cell geometry and sources distribution model for Monte Carlo single cell dosimetry with iodine 125 radioimmunotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Arnaud, F.X. [Université Toulouse III-Paul Sabatier, INPT, LAPLACE, F-31062 Toulouse (France); CNRS, LAPLACE, F-31062 Toulouse (France); Paillas, S. [IRCM, Institut de Recherche en Cancérologie de Montpellier, Montpellier F-34298 (France); INSERM, U1194, Montpellier F-34298 (France); Pouget, J.P [IRCM, Institut de Recherche en Cancérologie de Montpellier, Montpellier F-34298 (France); INSERM, U1194, Montpellier F-34298 (France); Université de Montpelllier, F-34090 Montpellier (France); Institut régional du Cancer de Montpellier, F-34298 Montpellier (France); Incerti, S. [Université Bordeaux, CENBG, UMR 5797, F-33170 Gradignan (France); CNRS, IN2P3, CENBG, UMR 5797, F-33170 Gradignan (France); Bardiès, M. [Inserm, UMR1037 CRCT, F-31000 Toulouse (France); Université Toulouse III-Paul Sabatier, UMR1037 CRCT, F-31000 Toulouse (France); Bordage, M.C., E-mail: marie-claude.bordage@inserm.fr [Université Toulouse III-Paul Sabatier, INPT, LAPLACE, F-31062 Toulouse (France); CNRS, LAPLACE, F-31062 Toulouse (France); Inserm, UMR1037 CRCT, F-31000 Toulouse (France); Université Toulouse III-Paul Sabatier, UMR1037 CRCT, F-31000 Toulouse (France)

    2016-01-01

    In cellular dosimetry, common assumptions consider concentric spheres for nucleus and cell and uniform radionuclides distribution. These approximations do not reflect reality, specially in the situation of radioimmunotherapy with Auger emitters, where very short-ranged electrons induce hyper localised energy deposition. A realistic cellular dosimetric model was generated to give account of the real geometry and activity distribution, for non-internalizing and internalizing antibodies (mAbs) labelled with Auger emitter I-125. The impact of geometry was studied by comparing the real geometry obtained from confocal microscopy for both cell and nucleus with volume equivalent concentric spheres. Non-uniform and uniform source distributions were considered for each mAbs distribution. Comparisons in terms of mean deposited energy per decay, energy deposition spectra and energy-volume histograms were calculated using Geant4. We conclude that realistic models are needed, especially when energy deposition is highly non-homogeneous due to source distribution.

  5. Regulation of autophagy via PERK-eIF2α effectively relieve the radiation myelitis induced by iodine-125.

    Directory of Open Access Journals (Sweden)

    Zuozhang Yang

    Full Text Available Radiation myelitis is the most serious complication in clinical radiotherapy for spinal metastases. We previously showed that (125I brachytherapy induced apoptosis of spinal cord neurons accompanied by autophagy. In this study, we further investigated the mechanism by which (125I radiation triggered autophagy in neural cells. We found that autophagy induced by (125I radiation was involved in endoplasmic reticulum (ER stress and mainly dependent on PERK-eIF2α pathway. The expressions of LC3II, ATG12 and PI3K were significantly suppressed in PERK knockout neural cells. Meanwhile, the expressions of phosphorylated-Akt s473 and caspase3/8 all significantly increased in neural cells transfected with a PERK siRNA and which enhanced apoptosis of neurons after (125I radiation. The results were consistent with that by MTT and Annexin-FITC/PT staining. In animal model of banna pigs with radiation myelitis caused by (125I brachytherapy, we have successfully decreased PERK expression by intrathecal administration of the lentivirus vector. The apoptosis rate was significantly higher than that in control group and which deteriorated radiation myelitis of banna pigs. Thus, autophagy caused by (125I radiation was mainly as an attempt of cell survival at an early stage, but it would be a self-destructive process and promoted the process of apoptosis and necrosis radiated by (125I for more than 72 hours. The study would be useful and helpful to maximize efficiency of radiation therapy in clinical therapy.

  6. Blood temperature profiles of diving elephant seals.

    Science.gov (United States)

    Meir, Jessica U; Ponganis, Paul J

    2010-01-01

    Hypothermia-induced reductions in metabolic rate have been proposed to suppress metabolism and prolong the duration of aerobic metabolism during dives of marine mammals and birds. To determine whether core hypothermia might contribute to the repetitive long-duration dives of the northern elephant seal Mirounga angustirostris, blood temperature profiles were obtained in translocated juvenile elephant seals equipped with a thermistor and backpack recorder. Representative temperature (the y-intercept of the mean temperature vs. dive duration relationship) was 37.2 degrees C +/- 0.6 degrees C (n=3 seals) in the extradural vein, 38.1 degrees C +/- 0.7 degrees C (n = 4 seals) in the hepatic sinus, and 38.8 degrees +/- 1.6 degrees C (n = 6 deals) in the aorta. Mean temperature was significantly though weakly negatively related to dive duration in all but one seal. Mean venous temperatures of all dives of individual seals ranged between 36 degrees and 38 degrees C, while mean arterial temperatures ranged between 35 degrees and 39 degrees C. Transient decreases in venous and arterial temperatures to as low as 30 degrees -33 degrees C occurred in some dives >30 min (0.1% of dives in the study). The lack of significant core hypothermia during routine dives (10-30 min) and only a weak negative correlation of mean temperature with dive duration do not support the hypothesis that a cold-induced Q(10) effect contributes to metabolic suppression of central tissues during dives. The wide range of arterial temperatures while diving and the transient declines in temperature during long dives suggest that alterations in blood flow patterns and peripheral heat loss contribute to thermoregulation during diving.

  7. SSME Seal Test Program: Test results for sawtooth pattern damper seal

    Science.gov (United States)

    Childs, D. W.

    1986-01-01

    Direct and transverse force coefficients for 11, sawtooth-pattern, and damper-seal configurations were examined. The designation damper seal uses a deliberately roughened stator and smooth rotor to increase the net damping force developed by a seal. The designation sawtooth-pattern refers to a stator roughness pattern. The sawtooth pattern yields axial grooves in the stator which are interrupted by spacer elements which act as flow constrictions or dams. All seals use the same smooth rotor and have the same, constant, minimum clearance. The stators examined the consequences of changes in the following design parameters: (1) axial-groove depth; (2) number of teeth: (3) number of sawtooth sections; (4) number of spacer elements; (5) dam width; (6) axially aligned sawtooth sections versus axially-staggered sawtooth sections; and (7) groove geometry. It is found that none of the sawtooth-pattern seal performs as well as the best round-hole-pattern seal. Maximum damping configurations for the sawtooth and round-hole-pattern stators have comparable stiffness performance. Several of the sawtooth pattern stators outperformed the best round-hole pattern seal.

  8. Miniature magnetic fluid seal working in liquid environments

    Energy Technology Data Exchange (ETDEWEB)

    Mitamura, Yoshinori, E-mail: ymitamura@par.odn.ne.jp [Graduate School of Information Science and Technology, Hokkaido University, Sapporo 060-0814 (Japan); Durst, Christopher A., E-mail: chris@procyrion.com [Procyrion, Inc., Houston, TX 77027 (United States)

    2017-06-01

    This study was carried out to develop a miniature magnetic fluid (MF) seal working in a liquid environment. The miniature MF seal is intended for use in a catheter blood pump. The requirements for the MF seal included a size of less than Ø4×4.5 mm, shaft diameter of 1 mm, sealing pressure of 200 mmHg, shaft speed of up to 40000 rpm, and life of one month. The miniature MF seal was composed of an NdFeB magnet (Ø4×Ø2×1) sandwiched between two pole pieces (Ø4×Ø1.1×0.5). A shield (Ø4×Ø1.2×1.5) was placed on the pole piece facing the liquid to minimize the influence of pump flow on the MF. The seal was installed on a Ø1 shaft. A seal was formed by injecting MF (Ms: 47.8 kA/m and η: 0.5 Pa·sec) into the gap between the pole pieces and the shaft. Total volume of the MF seal was 44 μL. A sealing pressure of 370 mmHg was obtained at motor speeds of 0-40,000 rpm. The seal remained perfect for 10 days in saline under the condition of a pump flow of 1.5 L/min (The test was terminated in accordance with plans). The seal remained intact after ethylene oxide sterilization during which the seal was exposed to high pressures. In conclusion, the newly developed MF seal will be useful for a catheter pump. - Highlights: • A miniature magnetic fluid seal working in a liquid environment was developed. • The seal can be installed on Ø1 mm shaft and can seal against 370 mmHg at 40000 rpm. • The magnetic fluid seal will be useful for a catheter blood pump.

  9. Numerical Investigation on Windback Seals Used in Aero Engines

    Directory of Open Access Journals (Sweden)

    Michael Flouros

    2018-01-01

    Full Text Available Seals are considered one of the most important flow elements in turbomachinery applications. The most traditional and widely known seal is the labyrinth seal but in recent years other types like the brush or carbon seals were introduced since they considerably reduce the sealing air consumption. When seals are used for sealing of aero engine bearing chambers they are subjected to high “bombardment” through oil particles which are present in the bearing chamber. These particles mainly result from the bearings as a consequence of the high rotational speeds. Particularly when carbon or brush seals are used, problems with carbon formation (coking may arise when oil gets trapped in the very tight gap of these seals. In order to prevent oil migration into the turbomachinery, particularly when the pressure difference over a seal is small or even negligible, significant improvement can be achieved through the introduction of so called windback seals. This seal has a row of static helical teeth (thread and below this thread a scalloped or smooth shaft section is rotating. Depending on the application, a windback seal can be used alone or as a combination with another seal (carbon, brush or labyrinth seal. A CFD analysis carried out with ANSYS CFX version 11 is presented in this paper with the aim to investigate this seal type. The simulations were performed by assuming a two-phase flow of air and oil in the bearing compartment. Design parameters like seal clearance, thread size, scallop width, were investigated at different operating conditions.

  10. Dynamic analysis of C/C composite finger seal

    Directory of Open Access Journals (Sweden)

    Chen Guoding

    2014-06-01

    Full Text Available A seal device as an important component of aeroengines has decisive influence on performance, reliability, and working life of aeroengines. With the development of aeroengines, demands on the performance characteristics of seal devices are made strictly. Finger seal as a novel kind of sealing device, recently attracts more and more attentions in academic circles and engineering fields at home and abroad. Research on finger seals has been extensively developed, especially on leakage and wear performances under dynamic conditions. However, it is a pity that the work on finger seals has been limited with a single approach that is improving the performance by structural optimization; in addition, the technology of dynamic analysis on finger seals is weak. Aiming at the problems mentioned above, a distributed mass equivalent dynamic model of finger seals considering the coupling effect of overlaid laminates is established in the present paper, the dynamic performance of 2.5 dimension C/C composite finger seal is analyzed with the model, and then the effects of fiber bundle density and fiber bundle preparation direction on finger seal’s dynamic performance are discussed, as well as compared with those of Co-based alloy finger seal. The current work is about dynamic analysis of finger seals and application of C/C composite in this paper may have much academic significance and many engineering values for improving research level of finger seal dynamics and exploring feasibility of C/C composite being used for finger seals.

  11. Effect of sealing on the morphology of anodized aluminum oxide

    International Nuclear Information System (INIS)

    Hu, Naiping; Dong, Xuecheng; He, Xueying; Browning, James F.; Schaefer, Dale W.

    2015-01-01

    Highlights: • We explored structural change of anodizing aluminum oxide induced by sealing. • All sealing methods decrease pore size as shown by X-ray/neutron scattering. • Cold sealing and hot water sealing do not alter the aluminum oxide framework. • Hot nickel acetate sealing both fills the pores and deposits on air oxide interface. • Samples with hot nickel acetate sealing outperform other sealing methods. - Abstract: Ultra-small angle X-ray scattering (USAXS), small-angle neutron scattering (SANS), X-ray reflectometry (XRR) and neutron reflectometry (NR) were used to probe structure evolution induced by sealing of anodized aluminum. While cold nickel acetate sealing and hot-water sealing decrease pore size, these methods do not alter the cylindrical porous framework of the anodic aluminum oxide layer. Hot nickel acetate both fills the pores and deposits on the air surface (air–oxide interface), leading to low porosity and small mean pore radius (39 Å). Electrochemical impedance spectroscopy and direct current polarization show that samples sealed by hot nickel acetate outperform samples sealed by other sealing methods

  12. Space Shuttle Orbiter AFT heat shield seal

    Science.gov (United States)

    Walkover, L. J.

    1979-01-01

    The evolution of the orbiter aft heat shield seal (AHSS) design, which involved advancing mechanical seal technology in severe thermal environment is discussed. The baseline design, various improvements for engine access, and technical problem solution are presented. It is a structure and mechanism at the three main propulsion system (MPS) engine interfaces to the aft compartment structure. Access to each MPS engine requires disassembly and removal of the AHSS. Each AHSS accommodates the engine movement, is exposed to an extremely high temperature environment, and is part of the venting control of the aft compartment.

  13. Cadmium Toxicity to Ringed Seals (Phoca hispida)

    DEFF Research Database (Denmark)

    Sonne, Christian; Dietz, R.; Riget, F. F.

    Cadmium concentrations in kidneys from ringed seals (Phoca hispida) from North West Greenland (Qaanaaq) are high. Concentrations range at level known to induce renal toxic effects (mainly tubulopathy) and demineralisation (osteopenia) of the skeletal system (Fanconi's Syndrome) in humans as well...... as laboratory mammals. We have studied possible cadmium induced histopathological changes in the kidneys as well as a demineralisation of the skeletal system (DXA-scanning of lumbal vertebraes). No obvious cadmium induced toxic changes were found. Food composition and physiological adaptations may explain...... the absence of toxic effects of cadmium in ringed seal...

  14. Producing the target seed: Seed collection, treatment, and storage

    Science.gov (United States)

    Robert P. Karrfalt

    2011-01-01

    The role of high quality seeds in producing target seedlings is reviewed. Basic seed handling and upgrading techniques are summarized. Current advances in seed science and technology as well as those on the horizon are discussed.

  15. Reactor coolant pump shaft seal behavior during station blackout

    International Nuclear Information System (INIS)

    Kittmer, C.A.; Wensel, R.G.; Rhodes, D.B.; Metcalfe, R.; Cotnam, B.M.; Gentili, H.; Mings, W.J.

    1985-04-01

    A testing program designed to provide fundamental information pertaining to the behavior of reactor coolant pump (RCP) shaft seals during a postulated nuclear power plant station blackout has been completed. One seal assembly, utilizing both hydrodynamic and hydrostatic types of seals, was modeled and tested. Extrusion tests were conducted to determine if seal materials could withstand predicted temperatures and pressures. A taper-face seal model was tested for seal stability under conditions when leaking water flashes to steam across the seal face. Test information was then used as the basis for a station blackout analysis. Test results indicate a potential problem with an elastomer material used for O-rings by a pump vendor; that vendor is considering a change in material specification. Test results also indicate a need for further research on the generic issue of RCP seal integrity and its possible consideration for designation as an unresolved safety issue

  16. Bentonite as a waste isolation pilot plant shaft sealing material

    International Nuclear Information System (INIS)

    Daemen, J.; Ran, Chongwei

    1996-12-01

    Current designs of the shaft sealing system for the Waste Isolation Pilot Plant (WIPP) propose using bentonite as a primary sealing component. The shaft sealing designs anticipate that compacted bentonite sealing components can perform through the 10,000-year regulatory period and beyond. To evaluate the acceptability of bentonite as a sealing material for the WIPP, this report identifies references that deal with the properties and characteristics of bentonite that may affect its behavior in the WIPP environment. This report reviews published studies that discuss using bentonite as sealing material for nuclear waste disposal, environmental restoration, toxic and chemical waste disposal, landfill liners, and applications in the petroleum industry. This report identifies the physical and chemical properties, stability and seal construction technologies of bentonite seals in shafts, especially in a saline brine environment. This report focuses on permeability, swelling pressure, strength, stiffness, longevity, and densification properties of bentonites

  17. Improvement in oil seal performance of gas compressor in HTTR

    International Nuclear Information System (INIS)

    Oyama, Sunao; Hamamoto, Shimpei; Nemoto, Takahiro; Sekita, Kenji; Isozaki, Minoru; Emori, Kouichi; Ohta, Yukimaru; Mizushima, Toshihiko; Kaneshiro, Noriyuki; Ito, Yoshiteru; Yamamoto, Hideo

    2007-08-01

    High-Temperature engineering Test Reactor (HTTR) built by Japan Atomic Energy Agency (JAEA) has reciprocating compressor commonly used to extract and discharge helium gas into primary/secondary coolant helium loop from helium purification system. Piston rod seal of the compressor consist of several components to prevent coolant leak. However, rod seal system has weak reliability during long term operation due to repeated leakage of seal oil in operation. As a result of investigations, leakage's root is found in that seal were used in a range beyond limit sliding properties of seal material. For this reason, a lip of the seal was worn and transformed itself and was not able to sustain a seal function. Therefore, through tests using facility actual equipment for endurance of candidate materials, one seal material were chosen for long term operation. (author)

  18. HMSRP Hawaiian Monk Seal Master Identification Records (annual)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains records of all individually identified Hawaiian monk seals since 1981. These seals were identified by PSD personnel and cooperating scientists...

  19. Dynamic Instability of Undamped Bellows Face Seals in Cryogenic Liquid

    National Research Council Canada - National Science Library

    Hudelson, John C

    1966-01-01

    .... The results of the tests indicated that dynamic instability will occur in undamped bellows face seals operating in a cryogenic environment and be of such a magnitude as to damage the sealing surface...

  20. An Update on Structural Seal Development at NASA GRC

    Science.gov (United States)

    Dunlap, Pat; Steinetz, Bruce; Finkbeiner, Josh; DeMange, Jeff; Taylor, Shawn; Daniels, Chris; Oswald, Jay

    2006-01-01

    A viewgraph presentation describing advanced structural seal development for NASA exploration is shown. The topics include: 1) GRC Structural Seals Team Research Areas; 2) Research Areas & Objective; 3) Wafer Seal Geometry/Flow Investigations; 4) Wafer Seal Installation DOE Study; 5) Results of Wafer Seal Installation DOE Study; 6) Wafer Geometry Study: Thickness Variations; 7) Wafer Geometry Study: Full-Size vs. Half-Size Wafers; 8) Spring Tube Seal Development; 9) Resiliency Improvement for Rene 41 Spring Tube; 10) Spring Tube Seals: Go-Forward Plan; 11) High Temperature Seal Preloader Development: TZM Canted Coil Spring; 12) TZM Canted Coil Spring Development; 13) Arc Jet Test Rig Development; and 14) Arc Jet Test Rig Status.

  1. Magnetic nanofluids and magnetic composite fluids in rotating seal systems

    International Nuclear Information System (INIS)

    Borbath, T; Borbath, I; Boros, T; Bica, D; Vekas, L; Potencz, I

    2010-01-01

    Recent results are presented concerning the development of magnetofluidic leakage-free rotating seals for vacuum and high pressure gases, evidencing significant advantages compared to mechanical seals. The micro-pilot scale production of various types of magnetizable sealing fluids is shortly reviewed, in particular the main steps of the chemical synthesis of magnetic nanofluids and magnetic composite fluids with light hydrocarbon, mineral oil and synthetic oil carrier liquids. The behavior of different types of magnetizable fluids in the rotating sealing systems is analyzed. Design concepts, some constructive details and testing procedures of magnetofluidic rotating seals are presented such as the testing equipment. The main characteristics of several magnetofluidic sealing systems and their applications will be presented: vacuum deposition systems and liquefied gas pumps applications, mechanical and magnetic nanofluid combined seals, gas valves up to 40 bar equipped by rotating seal with magnetic nanofluids and magnetic composite fluids.

  2. Performance evaluation of seal coat materials and designs.

    Science.gov (United States)

    2011-01-01

    "This project presents an evaluation of seal coat materials and design method. The primary objectives of this research are 1) to evaluate seal coat performance : from various combinations of aggregates and emulsions in terms of aggregate loss; 2) to ...

  3. Performance oriented guidance for Mississippi chip seals - volume II.

    Science.gov (United States)

    2013-12-01

    A laboratory and field study was conducted related to long term chip seal performance. This reports primary : objective was to initiate development of a long term performance (LTP) test protocol for chip seals focused on : aggregate retention. Key...

  4. Bismuth alloy potting seals aluminum connector in cryogenic application

    Science.gov (United States)

    Flower, J. F.; Stafford, R. L.

    1966-01-01

    Bismuth alloy potting seals feedthrough electrical connector for instrumentation within a pressurized vessel filled with cryogenic liquids. The seal combines the transformation of high-bismuth content alloys with the thermal contraction of an external aluminum tube.

  5. Seed dormancy and germination.

    Science.gov (United States)

    Penfield, Steven

    2017-09-11

    Reproduction is a critical time in plant life history. Therefore, genes affecting seed dormancy and germination are among those under strongest selection in natural plant populations. Germination terminates seed dispersal and thus influences the location and timing of plant growth. After seed shedding, germination can be prevented by a property known as seed dormancy. In practise, seeds are rarely either dormant or non-dormant, but seeds whose dormancy-inducing pathways are activated to higher levels will germinate in an ever-narrower range of environments. Thus, measurements of dormancy must always be accompanied by analysis of environmental contexts in which phenotypes or behaviours are described. At its simplest, dormancy can be imposed by the formation of a simple physical barrier around the seed through which gas exchange and the passage of water are prevented. Seeds featuring this so-called 'physical dormancy' often require either scarification or passage through an animal gut (replete with its associated digestive enzymes) to disrupt the barrier and permit germination. In other types of seeds with 'morphological dormancy' the embryo remains under-developed at maturity and a dormant phase exists as the embryo continues its growth post-shedding, eventually breaking through the surrounding tissues. By far, the majority of seeds exhibit 'physiological dormancy' - a quiescence program initiated by either the embryo or the surrounding endosperm tissues. Physiological dormancy uses germination-inhibiting hormones to prevent germination in the absence of the specific environmental triggers that promote germination. During and after germination, early seedling growth is supported by catabolism of stored reserves of protein, oil or starch accumulated during seed maturation. These reserves support cell expansion, chloroplast development and root growth until photoauxotrophic growth can be resumed. Crown Copyright © 2017. Published by Elsevier Ltd. All rights reserved.

  6. Reliability Driven Standardization of Mechanical Seals for Petrochemical Applications

    OpenAIRE

    Compagno, Lucio; Trapani, Natalia

    2014-01-01

    Part 1: Knowledge-Based Performance Improvement; International audience; Mechanical seals are the most diffuse solution for rotating shaft sealing because of their high safety performances and low maintenance costs. The only requirement to meet high service level is a care in the choice of a sealing system suitable for fluids treated and operating conditions. Mechanical seal manufacturers usually have very large catalogues with a wide mix of products for each use and also offers to their clie...

  7. Ecology, tourism and management of harbour seals (Phoca vitulina)

    OpenAIRE

    Granquist, Sandra M.

    2016-01-01

    In cases where human and wildlife are co-using the same geographical areas and resources, management issues often get complex and stakeholder conflicts are common. The Icelandic harbour seal (Phoca vitulina) population is rapidly decreasing, but direct culling of seals still occurs. At the same time seals are becoming an important resource due to increased interest in wildlife watching. Despite the complicated management situation, the Icelandic harbour seal population is one of the least stu...

  8. Development of Advanced Carbon Face Seals for Aircraft Engines

    Science.gov (United States)

    Falaleev, S. V.; Bondarchuk, P. V.; Tisarev, A. Yu

    2018-01-01

    Modern aircraft gas turbine engines require the development of seals which can operate for a long time with low leakages. The basic type of seals applied for gas turbine engine rotor supports is face seal. To meet the modern requirements of reliability, leak-tightness and weight, low-leakage gas-static and hydrodynamic seals have to be developed. Dry gas seals use both gas-static and hydrodynamic principles. In dry gas seals microgrooves are often used, which ensure the reverse injection of leakages in the sealed cavity. Authors have developed a calculation technique including the concept of coupled hydrodynamic, thermal and structural calculations. This technique allows to calculate the seal performance taking into account the forces of inertia, rupture of the lubricant layer and the real form of the gap. Authors have compared the efficiency of seals with different forms of microgrooves. Results of calculations show that seal with rectangular form of microgrooves has a little gap leading to both the contact of seal surfaces and the wear. Reversible microgrooves have a higher oil mass flow rate, whereas HST micro-grooves have good performance, but they are difficult to produce. Spiral microgrooves have both an acceptable leakages and a high stiffness of liquid layer that is important in terms of ensuring of sealing performance at vibration conditions. Therefore, the spiral grooves were chosen for the developed seal. Based on calculation results, geometric dimensions were chosen to ensure the reliability of the seal operation by creating a guaranteed liquid film, which eliminates the wear of the sealing surfaces. Seals designed were tested both at the test rig and in the engine.

  9. 7 CFR 205.311 - USDA Seal.

    Science.gov (United States)

    2010-01-01

    ... PROVISIONS NATIONAL ORGANIC PROGRAM Labels, Labeling, and Market Information § 205.311 USDA Seal. (a) The... (2) On a white or transparent background with black outer circle and black “USDA” on a white or transparent upper half of the circle with a contrasting white or transparent “organic” on the black lower half...

  10. Measure Guideline: Guide to Attic Air Sealing

    Energy Technology Data Exchange (ETDEWEB)

    Lstiburek, J.

    2014-09-01

    The Guide to Attic Air Sealing was completed in 2010 and although not in the standard Measure Guideline format, is intended to be a Measure Guideline on Attic Air Sealing. The guide was reviewed during two industry stakeholders meetings held on December 18th, 2009 and January 15th, 2010, and modified based on the comments received. Please do not make comments on the Building America format of this document. The purpose of the Guide to Attic Air Sealing is to provide information and recommendations for the preparation work necessary prior to adding attic insulation. Even though the purpose of this guide is to save energy - health, safety and durability should not be compromised by energy efficiency. Accordingly, combustion safety and ventilation for indoor air quality are addressed first. Durability and attic ventilation then follow. Finally, to maximize energy savings, air sealing is completed prior to insulating. The guide is intended for home remodelers, builders, insulation contractors, mechanical contractors, general contractors who have previously done remodeling and homeowners as a guide to the work that needs to be done.

  11. A morbillivirus causing mass mortality in seals.

    NARCIS (Netherlands)

    A.D.M.E. Osterhaus (Albert)

    1989-01-01

    textabstractDuring an outbreak of a serious apparently infectious disease among harbour seals (Phoca vitulina), which started in the Kattegat area in April 1988 and rapidly spread to the North sea, the Wadden sea and the Baltic sea, greater than 17,000 animals died within a period of eight months.

  12. Sealing materials for solid oxide fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Larsen, P.H.

    1999-02-01

    A major obstacle in the achievement of high electrical efficiency for planar solid oxide fuel cell stacks (SOFC) is the need for long term stable seals at the operational temperature between 850 and 1000 deg. C. In the present work the formation and properties of sealing materials for SOFC stacks that fulfil the necessary requirements were investigated. The work comprises analysis of sealing material properties independently, in simple systems as well as tests in real SOFC stacks. The analysed sealing materials were based on pure glasses or glass-ceramic composites having B{sub 2}O{sub 3}, P{sub 2}O{sub 5} or siO{sub 2} as glass formers, and the following four glass systems were investigated: MgO/caO/Cr{sub 2}O{sub 3}-Al{sub 2}O{sub 3}B{sub 2}O{sub 3}-P{sub 2}O{sub 5}, MgO-Al{sub 2}O{sub 3}-P{sub 2}O{sub 5}, MgO-Al{sub 2}O{sub 3}-P{sub 2}O{sub 5}-SiO{sub 2} and BaO/Na{sub 2}O-Al{sub 2}O{sub 3}-SiO{sub 2}. (au) 32 tabs., 106 ills., 107 refs.

  13. K-Basin isolation barrier seal

    International Nuclear Information System (INIS)

    Ruff, E.S.

    1994-10-01

    This report documents various aspects of the design, analysis, procurement, and fabrication of the hydraulic seal on the isolation barriers to be installed in the 100-K Area spent nuclear fuel basin. The isolation barrier is used to keep water in the basin in the event of an earthquake

  14. Liquid-hydrogen/nuclear-radiation resistant seals

    Science.gov (United States)

    Van Auken, R.

    1971-01-01

    Seal employs aromatic heterocyclic polymer, polyquinoxaline, and features resin starved laminate consisting of alternate layers of woven glass fabric and polymer film. Design gives gasket a mechanical spring characteristic, eliminating cold flow and resulting in elastic recovery when gasket is unloaded.

  15. Pressure Gauges Monitor Leakage Past Seals

    Science.gov (United States)

    Smith, Steven A.

    1990-01-01

    Method devised to measure leakage of gas past each of two sets of primary and secondary seals into common volume from which aggregate flow measured. Although method applicable only to specific combination of flow configuration and thermal conditions, it serves as example of more general approach involving use of statistical analysis to extract additional information from measurements.

  16. leonina and Cape fur seals Arctocephalus pusillus

    African Journals Online (AJOL)

    cows or yearling/subadult individuals from size and ap- pearance. .... The penis was then everted and rubbed across the rump and hindflip- pers of the fur seal: successful intromission was never observed (Fig. 2H). Pelvic thrusts followed, and were timed on three ... the smaller size of A. p. pusillus cows (averaging 70 kg as.

  17. The Navy SEAL Physical Fitness Guide

    Science.gov (United States)

    1997-08-01

    Some severe sprains may require surgical intervention . Overtraining Syndrome The most common physical conditioning error for the SEAL operator is...after its use. Importantly, transmission of hepatitis B and AIDS can occur from needle or drug sharing. Various cancers have also been associated with...Anabolic Steroids in Men: Physiologic and Psychological Physiological Effects Irreversible Breast enlargement Atrophy of the testicles May Be

  18. Radioactive sealed sources inventory and management

    International Nuclear Information System (INIS)

    Rodriguez C, G.; Mallaupoma G, M.; Cruz C, W.

    1996-01-01

    This report is related to the management of radioactive wastes, that is to say, related to the sealed sources utilized in industry, medicine and research jobs, that can not be used anymore, because of their life time termination or their activity decay to useless limits. Owing to this fact, it is necessary to take them to the Management Plant of Radioactive waste in the 'RACSO' Nuclear Center, as it is specified by the National Authority Technical Office (OTAN) regulations in Peru. The experience gained by IPEN in the sealed source management is shown in the table which informs about the radionuclide types, activity and volume amount for years. In the 'RACSO' Nuclear Center, 63 sealed sources are stored and right measures are being adopted in order to be conditioned by cementation in 200 lt steel reinforced cylinders, which are proper to their transportation and storage. A flow-chart shows the steps that the national users should follow in order to manage radioactive sealed sources and so that minimize the risks. Resulting from the agreement between the users and managers, a systematic coordination is developed, verifying the information related to the source characterization, the way of transportation and the future conditioning. It also involves the cost aspects, which in some cases, represent a big problem in the management. (authors). 3 refs., 3 figs., 1 tab

  19. Bearings and Seals. FOS: Fundamentals of Service.

    Science.gov (United States)

    John Deere Co., Moline, IL.

    This manual on bearings and seals is one of a series of power mechanics texts and visual aids for use in training for the servicing of automotive and off-the-road farm and industrial machines. Materials provide basic information and illustrations for use by vocational students and teachers as well as shop servicemen and laymen. Focusing on…

  20. Seed thioredoxin h

    DEFF Research Database (Denmark)

    Hägglund, Per; Finnie, Christine; Yano, Hiroyuki

    2016-01-01

    , for example chloroplastic f- and m-type thioredoxins involved in regulation of the Calvin-Benson cycle. The cytosolic h-type thioredoxins act as key regulators of seed germination and are recycled by NADPH-dependent thioredoxin reductase. The present review on thioredoxin h systems in plant seeds focuses...

  1. (Cuminum cyminum L.) seeds

    African Journals Online (AJOL)

    lenovo

    2013-08-19

    Aug 19, 2013 ... Changes in fatty acids were studied during maturation of cumin (Cuminum cyminum L.) seeds cultivated in the ... Key words: Cumin (Cuminum cyminum L.), Apiaceae, seed, fatty acids composition, petroselinic acid, maturation. ..... atherosclerosis, autoimmune disorder, diabetes and other diseases.

  2. THE PROBLEMS AND PROSPECTS OF THE USE OF ELASTOMER SEALS FOR SEALING OF UNDERGROUND STRUCTURES

    Directory of Open Access Journals (Sweden)

    L. H. Politikova

    2007-10-01

    Full Text Available The research work on creation of effective rubber sealants for hermetic sealing of joints of underground structures from modular ferro-concrete and pig-iron including the underground tunnel casings is carried out.

  3. 48 CFR 570.105-3 - Sealed bidding.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 4 2010-10-01 2010-10-01 false Sealed bidding. 570.105-3 Section 570.105-3 Federal Acquisition Regulations System GENERAL SERVICES ADMINISTRATION SPECIAL... sealed bidding, use the procedures in FAR part 14. In most cases you should not use sealed bidding to...

  4. Nuclear reactor having an inflatable vessel closure seal structure

    International Nuclear Information System (INIS)

    1980-01-01

    An improved type of closure head seal for the rotatable plugs of the reactor vessel of a liquid metal fast breeder reactor is described. The seal prevents the release of radioactive particles while allowing the plug to be rotated without major manipulation of the seal structure. (UK)

  5. Short communications Goose barnacles on seals and a penguin at ...

    African Journals Online (AJOL)

    During a survey of seals in September and October 2009 at Gough Island, South Atlantic Ocean, we recorded goose barnacles (Lepas australis) attached to the pelage of two of the 12 elephant seals (Mirounga leonina) inspected and one of the seven vagrant Antarctic fur seals (Arctocephalus gazella) which were found ...

  6. Moult in the Mediterranean monk seal from Cap Blanc, western ...

    African Journals Online (AJOL)

    It is different to that of the Hawaiian monk seal and elephant seals, as Mediterranean monk seals partly moult in the water. The intermoult period was close to one year except in females nursing a pup. Such females have longer intermoult periods and can even moult whilst still lactating. In males, the process of developing ...

  7. POPULATION NUMBERS OF FUR SEALS AT PRINCE EDWARD ...

    African Journals Online (AJOL)

    During the period 17–22 December 2001, the onshore distribution and the abundance of Antarctic fur seals Arctocephalus gazella and Subantarctic fur seals A. tropicalis were determined for Prince Edward Island. Two breeding colonies of Antarctic fur seals were located on the south-east coast of the island; the first a mixed ...

  8. Preliminary comparison of calls of the hybridizing fur seals ...

    African Journals Online (AJOL)

    Preliminary comparison of calls of the hybridizing fur seals Arctocephalus tropicalis and A. gazella. M. St Clair Hill, J.W.H. Ferguson, M.N. Bester, G.I.H. Kerley. Abstract. The Antarctic fur seal (Arctocephalus gazella) and the Subantarctic fur seal (A. tropicalis) hybridize on a relatively small scale at Marion Island. To date the ...

  9. Fluctuations in the population of southern elephant seals Mirounga ...

    African Journals Online (AJOL)

    and seals (Laws 1973). Predation. Carrick and Ingham (1962) indicated that the killer whale. Orcinus orca is an important predator of elephant seals, es- pecially of immature individuals. Moreover, Condy (1977) suggests that the observed decrease in the elephant seal population at Marion Island is due to a lowered recruit-.

  10. Computer tools for face seal analyses developed at John Crane

    Science.gov (United States)

    Wu, Shifeng

    1994-01-01

    The purposes of the computer tools for face seal analysis are new product optimization, existing seals on new applications, existing seals on off-duty conditions, and trouble-shooting. Discussed in this viewgraph presentation are interface forces, friction/heat generation, heat transfer/temperature distribution, axisymmetric pressure/thermal distortion, leakage, and an example case.

  11. Test of Seal System for Flexible Pipe End Fitting

    DEFF Research Database (Denmark)

    Banke, Lars; Jensen, Thomas Gregers

    1999-01-01

    The purpose of the end fitting seal system is to ensure leak proof termination of flexible pipes. The seal system of an NKT end fitting normally consists of a number of ring joint gaskets mounted in a steel sleeve on the outside of the polymeric inner liner of the pipe. The seal system is activated...

  12. 14 CFR 1221.102 - Establishment of the NASA Seal.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 5 2010-01-01 2010-01-01 false Establishment of the NASA Seal. 1221.102 Section 1221.102 Aeronautics and Space NATIONAL AERONAUTICS AND SPACE ADMINISTRATION THE NASA SEAL AND OTHER DEVICES, AND THE CONGRESSIONAL SPACE MEDAL OF HONOR NASA Seal, NASA Insignia, NASA Logotype, NASA...

  13. 14 CFR 1221.109 - Use of the NASA Seal.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 5 2010-01-01 2010-01-01 false Use of the NASA Seal. 1221.109 Section 1221.109 Aeronautics and Space NATIONAL AERONAUTICS AND SPACE ADMINISTRATION THE NASA SEAL AND OTHER DEVICES, AND THE CONGRESSIONAL SPACE MEDAL OF HONOR NASA Seal, NASA Insignia, NASA Logotype, NASA Program...

  14. Seal boxes from the Viminacium site

    Directory of Open Access Journals (Sweden)

    Milovanović Bebina

    2013-01-01

    Full Text Available Bronze seal boxes that had the function of holding the wax seal on the Viminacium site - Upper Moesia (Stari Kostolac, Serbia, mainly from the area of the necropolis (ten were found in the graves and ten at the cemetery between the graves. Six are from buildings that had a storage function, five are from public facilities - an amphitheatre, and only one find is from the military fort of the legion VII Claudia, which was stationed in Viminacium in the second half of the 1st century. Thirty-two seal boxes have been processed: nine whole, six with fragmented upper and lower parts, seven bases and ten covers. Seal boxes consist of two parts: the cover and the base. The cover is decorated with figural images, concentric rings and especially with applied ornaments. Some of the motifs are filled with enamel. The base always has three to five circular perforations at the bottom, the side walls are a height of 4 to 5 mm with two opposed notches or slots which are thought to have facilitated the tying of the seal box to a package or a document. The lock mechanism is operated using the hinges principle. Some specimens have a circular extension on the cover with a thorn on the bottom. This fits the hollow in the base, through which passes a thorn for the additional fixing of the cover. Based on shape and decoration, seal boxes were classified into five types: I - elliptical or oval shaped with a figural representation on the cover derived in relief; II/1 - leaf or heart-shaped with a special, riveted ornament; II/2 - leaf or heart-shaped with enamel on the cover; III/1 - circular showing a form in relief; III/2 - circular with cast concentric rings, with no enamel; III/3 - circular with concentric rings with enamel on the cover; IV - diamond shaped with enamel on the cover and V - square with enamel on the cover. The seal boxes dominate chronologically from the first half of the 2nd and throughout the 3rd century.

  15. Neutron irradiation of seeds

    International Nuclear Information System (INIS)

    1967-01-01

    Neutrons are a valuable type of ionizing radiation for seed irradiation and radiobiological studies and for inducing mutations in crop plants. In experiments where neutrons are used in research reactors for seed irradiation it is difficult to measure the dose accurately and therefore to establish significant comparisons between experimental results obtained in various reactors and between repeated experiments in the same reactor. A further obstacle lies in the nature and response of the seeds themselves and the variety of ways in which they are exposed in reactors. The International Atomic Energy Agency decided to initiate international efforts to improve and standardize methods of exposing seeds in research reactors and of measuring and reporting the neutron dose. For this purpose, an International Neutron Seed Irradiation Programme has been established. The present report aims to give a brief but comprehensive picture of the work so far done in this programme. Refs, figs and tabs

  16. ITER lip seal welding and cutting developments

    Energy Technology Data Exchange (ETDEWEB)

    Levesy, B.; Cordier, J.J.; Jokinen, T. [ITER Organization, Route de Vinon sur Verdon, 13115 Saint Paul Lez Durance (France); Kujanpää, V.; Karhu, M. [VTT Technical Research Centre of Finland (Finland); Le Barbier, R. [ITER Organization, Route de Vinon sur Verdon, 13115 Saint Paul Lez Durance (France); Määttä, T. [VTT Technical Research Centre of Finland (Finland); Martins, J.P.; Utin, Y. [ITER Organization, Route de Vinon sur Verdon, 13115 Saint Paul Lez Durance (France)

    2015-10-15

    Highlights: • Different TIG and Laser welding techniques are tested. • Twin spot laser welding techniques is the best. • Limited heat input gives a stable weld pool in all positions. • Penetrations is achieved. • Lip seal welding and cutting with a robotic arm is successfully performed on a representative mock-up. - Abstract: The welded lip seals form part of the torus primary vacuum boundary in between the port plugs and the vacuum vessel, and are classified as Protection Important Component. In order to refurbish the port plugs or the in-vessel components, port plugs have to be removed from the machine. The lip seal design must enable up to ten opening of the vacuum vessel during the life time operation of the ITER machine. Therefore proven, remote reliable cutting and re-welding are essential, as these operations need to be performed in the port cells in a nuclear environment, where human presence will be restricted. Moreover, the combination of size of the components to be welded (∼10 m long vacuum compatible thin welds) and the congested environment close to the core of the machine constraint the type and size of tools to be used. This paper describes the lip seal cutting and welding development programme performed at the VTT Technical Research Centre, Finland. Potential cutting and welding techniques are analyzed and compared. The development of the cutting, TIG and laser welding techniques on samples are presented. Effects of lip seal misalignments and optimization of the 2 welding processes are discussed. Finally, the manufacturing and test of the two 1.2 m × 1 m representative mock-ups are presented. The set-up and use of a robotic arm for the mock-up cutting and welding operations are also described.

  17. Sealed source dismantling hot cell - startup

    Energy Technology Data Exchange (ETDEWEB)

    Dellamano, Jose Claudio; Ferreira, Robson de Jesus, E-mail: jcdellam@ipen.br, E-mail: rojefer@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil). Gerencia de Rejeitos radioativos

    2013-07-01

    Sealed radioactive sources are widely used in many applications of nuclear technology and at the end of the useful life, most sources become radioactive waste. In Brazil, this waste is received by the Institutes of the National Nuclear Energy Commission and kept under centralized storage. The Waste Management Department at the Nuclear and Energy Research Institute is the main storage center, having received around 20,000 disused sources. A hot cell was designed and constructed to manage Co-60 spent sealed sources with activity up to 3.7 10{sup 1}0 Bq and other sources with equivalent activities. In the hot cell the sources are withdraw from their original shielding and transferred to a standard shielding for further disposal off. The original shielding disassembling is made outside the hot cell and after opening, it is transferred inside the hot cell and the sealed source is removed remotely. The source is checked in relation to external contamination and its activity is checked. After this, the source is positioned in the standard shielding located inside an overpack at the bottom of the hot cell. This paper describes some pre-operational tests carried out in it, that include: opening and closing doors and locks, checking of all electrical and pneumatic controls, the original shielding movement inside the hot-cell, dose rate measurements outside the hot-cell, insertion of the sealed sources inside the activity meter chamber, transferring the sealed source to the standard shielding, movement of the overpack with the standard shielding to outside of the hot-cell and plugging of the standard shielding. (author)

  18. Release of allyl isothiocyanate from mustard seed meal powder.

    Science.gov (United States)

    Dai, Ruyan; Lim, Loong-Tak

    2014-01-01

    Allyl isothiocyanate (AITC) is a wide-spectrum antimicrobial compound found in mustard seeds, produced when their tissues are disrupted. The formation of AITC in mustard seed is mediated by the myrosinase enzyme which catalyzes the release of volatile AITC from a glucosinolate-sinigrin. Since water is a substrate in the reaction, humidity from the air can be used to activate the release of AITC from mustard seed. In this study, defatted and partially defatted mustard seed meals were ground into powders with particle size ranging from 5 to 300 μm. The mustard seed meal powder (MSMP) samples were enclosed within hermetically sealed glass jars wherein the headspace air was adjusted to 85% or 100% relative humidity at 5, 20, or 35 °C. Data from gas chromatography analysis showed that AITC release rate and amount increased with increasing relative humidity and temperature. Moreover, the release rate can be manipulated by particle size and lipid content of the MSMP samples. The amount of AITC released ranged from 2 to 17 mg/g MSMP within 24 h under the experimental conditions tested. In view of the antimicrobial properties of AITC, the mustard meal powder may be used as a natural antimicrobial material for extending the shelf life of food products. © 2013 Institute of Food Technologists®

  19. Biodegradation of genetically modified seeds and plant tissues during composting.

    Science.gov (United States)

    Reuter, Tim; Alexander, Trevor W; Xu, Weiping; Stanford, Kim; McAllister, Tim A

    2010-03-15

    The increasing global market of genetically modified (GM) crops amplifies the potential for unintentional contamination of food and feed with GM plants. Methods proposed for disposal of crop residues should be assessed to prevent unintended distribution of GM materials. Composting of organic material is inexpensive and location-independent. The objective of this study was to determine the effectiveness of composting for disposal of GM plants in terms of reducing seed viability and promoting the degradation of endogenous as well as transgenic DNA. Duplicate samples of corn kernels, alfalfa leaves, and GM canola seeds, meal and pellets were sealed in porous nylon bags and implanted in duplicate 85,000 kg (initial weight) feedlot manure compost piles. Samples were collected at intervals over 230 days of composing. Canola seeds and corn kernels were not viable after 14 days of composting with temperatures in the piles exceeding 50 degrees C. In all samples, PCR analyses revealed that plant endogenous and transgenic fragments were substantially degraded after 230 days of composting. Southern blotting of genomic DNA isolated from canola seeds identified differences in the persistence of endogenous, transgenic, and bacterial DNA. Composting GM and non-GM plant materials with manure rendered seeds non-viable, and resulted in substantial, although not complete, degradation of endogenous and transgenic plant DNA. This study demonstrates that composting could be effective for disposing of GM crops in the event of their inadvertent entry into the food or feed chain.

  20. Sealing properties of mechanical seals for an axial flow blood pump.

    Science.gov (United States)

    Tomioka, J; Mori, T; Yamazaki, K; Koyanagi, H

    1999-08-01

    A miniature intraventricular axial flow blood pump for left ventricular support is under development. One of the key technologies required for such pumps is sealing of the motor shaft. In this study, to prevent blood backflow into the motor side, mechanical seals were developed and their sealing properties investigated. In the experimental apparatus, the mechanical seal separated the bovine blood on the chamber side from the cooling water on the motor side. A leakage of the blood was measured by inductively coupled plasma (ICP) light emission analysis. The rate of hemolysis was measured by the cyanmethemoglobin method. Frictional torque acting on the shaft was measured by a torque transducer. In the experiments, the rotational speed of the shaft was changed from 1,000 to 10,000 rpm, and the contact force of the seal faces was changed from 1.96 to 4.31 N. To estimate lubrication regimes, the Stribeck curve, a diagram of the coefficient of friction against the bearing characteristic G number, was drawn. The results of the experiments showed that both the leakage of blood and the rate of hemolysis were very small. The friction loss was also very small. The mechanical seal was operated in various lubrication regimes, from a fluid lubrication regime to a mixed lubrication regime.

  1. Phagocytosis in pup and adult harbour, grey and harp seals.

    Science.gov (United States)

    Frouin, Héloïse; Lebeuf, Michel; Hammill, Mike; Fournier, Michel

    2010-04-15

    Knowledge on pinniped immunology is still in its infancy. For instance, age-related and developmental aspects of the immune system in pinnipeds need to be better described. The present study examined the phagocytic activity and efficiency of harbour, grey and harp seal leukocytes. In the first part of the study, peripheral blood was collected from captive female harbour seals of various ages. Data showed an age-related decrease in phagocytosis in female harbour seals from sub-adult to adulthood. In the second part of the study, changes in phagocytosis were quantified during lactation in wild newborn harbour, grey and harp seals and in their mothers (harp and grey seals). In newborns of the same age, leukocytes of harbour and harp seals phagocytosed less than those of grey seal pups. The phagocytic activity and efficiency increased significantly from early to mid-lactation in newborn harbour seals, and from early to late lactation in newborn grey seals, which could suggest that the transfer of phagocytosis-promoting factor(s) in colostrum is an important feature of temporary protection for pups. In contrast, no changes in phagocytic activity and efficiency were observed in lactating females of the two seal species, harp and grey, examined. At late lactation, phagocytic activity in both grey and harp seal pups and phagocytic efficiency in grey seal pups were significantly higher than in their mothers. These results could reflect either the capacity of phagocytes of the newborn harp and grey seals to respond to pathogens. Results from this study suggest that the phagocytosis of the seal species examined is not fully developed at birth as it generally increases in pups during lactation. Thereafter, the phagocytic activity of seals appears to decrease throughout adulthood. Copyright 2009 Elsevier B.V. All rights reserved.

  2. Organic leek seed production - securing seed quality

    DEFF Research Database (Denmark)

    Deleuran, Lise Christina; Boelt, Birte

    2011-01-01

    organic vegetable growers can get derogations to use non-organic seeds in their productions. Potentially, this could lead to the organic consumers’ loss of faith and interest in organic products. The pre-requisite for an organic vegetable production is the presence of organically produced high quality...

  3. Organic Leek Seed Production - Securing Seed Quality

    DEFF Research Database (Denmark)

    Deleuran, L C; Boelt, B

    2011-01-01

    organic vegetable growers can get derogations to use non-organic seeds in their productions. Potentially, this could lead to the organic consumers’ loss of faith and interest in organic products. The pre-requisite for an organic vegetable production is the presence of organically produced high quality...

  4. ASTUS system for verifying the transport seal TITUS 1

    International Nuclear Information System (INIS)

    Barillaux; Monteil, D.; Destain, G.D.

    1991-01-01

    ASTUS, a system for acquisition and processing ultrasonic signatures of TITUS 1 seals has been developed. TITUS seals are used to verify the integrity of the fissile material's container sealing after transport. An autonomous portable reading case permit to take seals signatures at the starting point and to transmit these reference signatures to a central safeguards computer by phonic modem. Then, at the terminal point with a similar reading case, an authority takes again the signature of seals and immediately transmit these signatures to the central safeguards computer. The central computer processes the data in real time by autocorrelation and return its verdict to the terminal point

  5. Effect of seed invigoration by osmopriming on seed quality ...

    African Journals Online (AJOL)

    An experiment was conducted to determine the influence of osmopriming techniques on seed lots of three Capsicum species. The seeds were primed using seven different solutions for three different priming durations. Primed seed lots were evaluated for seed germination, seedling vigour index, seedling emergence and ...

  6. Effects of seed fermentation method on seed germination and vigor ...

    African Journals Online (AJOL)

    The present study was conducted to examine the influence of Lagenaria siceraria seed fermentation method on seed germination and vigor. Three seed fermentation methods (fermented in ambient air, plastic bag stored in ambient or in plastic bag buried) were tested on two cultivars during two years. Seed germination and ...

  7. Effect of Genotypes and Seed Production Environments on Seed ...

    African Journals Online (AJOL)

    Seeds from each harvest were subjected to different seed quality tests and data generated were analyzed. Seed quality traits were considerably affected by the genotypes and growing conditions i.e. plant population and cropping seasons. Genotypes with superior seed quality were prevalent at 166.667 and 266.667 plants ...

  8. Experimental and Optimization Design of Offshore Drilling Seal

    Directory of Open Access Journals (Sweden)

    Zhang Yi

    2017-11-01

    Full Text Available Three-cone bit is the key equipment in the exploration of the oil in offshore drilling and exploration, the bearing system and the seal system are the critical components for the bit. Especially in the offshore drilling environment, the seal design need to be carefully considered. A multi-objective optimization design including orthogonal design method and F-test with finite element analysis for a three-cone bit seal is proposed. Firstly, the calculation method of optimization targets are given, including the minimization of maximum contact pressure and leakage rate analyzed by ANSYS and MATLAB respectively, to maximize seal life and reliability. Then, an orthogonal experiment approach is used to investigate the effects of the eleven parameters on the seal performance, and the influence degrees of the seal factors on the optimization targets have been confirmed by F-test, and the reasonable factors can be determined by the trend of the targets. Finally, in order to validate the analysis results, a new seal was designed and tested on a seal tester compared to the previous seal. In this test, the seal maximum interface temperature that reflects the position of maximum contact pressure can be obtained by using three high precision thermocouples. Both the experiment results and the numerical analyses proved that the maximum contact pressure and leakage rate of the improved seal have been reduced compared to the previous.

  9. VACOSS - variable coding seal system for nuclear material control

    International Nuclear Information System (INIS)

    Kennepohl, K.; Stein, G.

    1977-12-01

    VACOSS - Variable Coding Seal System - is intended to seal: rooms and containers with nuclear material, nuclear instrumentation and equipment of the operator, instrumentation and equipment at the supervisory authority. It is easy to handle, reusable, transportable and consists of three components: 1. Seal. The light guide in fibre optics with infrared light emitter and receiver serves as lead. The statistical treatment of coded data given in the seal via adapter box guarantees an extremely high degree of access reliability. It is possible to store the data of two undue seal openings together with data concerning time and duration of the opening. 2. The adapter box can be used for input or input and output of data indicating the seal integrity. 3. The simulation programme is located in the computing center of the supervisory authority and permits to determine date and time of opening by decoding the seal memory data. (orig./WB) [de

  10. Low torque hydrodynamic lip geometry for rotary seals

    Science.gov (United States)

    Dietle, Lannie L.; Schroeder, John E.

    2015-07-21

    A hydrodynamically lubricating geometry for the generally circular dynamic sealing lip of rotary seals that are employed to partition a lubricant from an environment. The dynamic sealing lip is provided for establishing compressed sealing engagement with a relatively rotatable surface, and for wedging a film of lubricating fluid into the interface between the dynamic sealing lip and the relatively rotatable surface in response to relative rotation that may occur in the clockwise or the counter-clockwise direction. A wave form incorporating an elongated dimple provides the gradual convergence, efficient impingement angle, and gradual interfacial contact pressure rise that are conducive to efficient hydrodynamic wedging. Skewed elevated contact pressure zones produced by compression edge effects provide for controlled lubricant movement within the dynamic sealing interface between the seal and the relatively rotatable surface, producing enhanced lubrication and low running torque.

  11. Material Research of Rotary Sealing Device for Combined Cutting System

    Directory of Open Access Journals (Sweden)

    Rui Zeng

    2017-01-01

    Full Text Available In order to solve the rotary sealing problem of rotary shaft in drum shearer combined cutting system, the material and structure of combined cutting system rotary sealing device needs to be selected and designed. In the paper, the rotary sealing structure of four grades in series was designed first, and then the material of NBR-40 and PTFE 4FT-4 under the separate static and dynamic sealing tests were carried out on the combined tooth-slip-ring sealing test-bed. The tests show that the NBR-40 O-Ring with PTFE 4FT-4 tooth-slip-ring has no low-pressure leakage problem and low leakage in the sealing progress, the sealing effect of which is the best.

  12. Apparatus and method for inspecting a sealed container

    Science.gov (United States)

    Harmon, J Frank [Pocatello, ID; Jones, James L [Idaho Falls, ID; Hunt, Alan W [Pocatello, ID; Spaulding, Randy J [Pocatello, ID; Smith, Michael [Phoenix, AZ

    2009-03-24

    An apparatus for inspecting a sealed container is disclosed and which includes a pulsed electron accelerator which is positioned in spaced relation relative to a first side of the sealed container, and which produces a pulsed beam of photons which passes through the sealed container and any contents enclosed within the sealed container; a detector positioned in spaced relation relative to a second, opposite side of the sealed container, and which receives the pulsed beam of photons which passes through the contents of the sealed container, and which produces an output signal; and a computer for developing a visible image from the output signal of the detector which depicts the contents of the sealed container.

  13. Method of making hermetic seals for hermetic terminal assemblies

    Science.gov (United States)

    Hsu, John S.; Marlino, Laura D.; Ayers, Curtis W.

    2010-04-13

    This invention teaches methods of making a hermetic terminal assembly comprising the steps of: inserting temporary stops, shims and jigs on the bottom face of a terminal assembly thereby blocking assembly core open passageways; mounting the terminal assembly inside a vacuum chamber using a temporary assembly perimeter seal and flange or threaded assembly interfaces; mixing a seal admixture and hardener in a mixer conveyor to form a polymer seal material; conveying the polymer seal material into a polymer reservoir; feeding the polymer seal material from the reservoir through a polymer outlet valve and at least one polymer outlet tube into the terminal assembly core thereby filling interstitial spaces in the core adjacent to service conduits, temporary stop, and the terminal assembly casing; drying the polymer seal material at room temperature thereby hermetically sealing the core of the terminal assembly; removing the terminal assembly from the vacuum chamber, and; removing the temporary stops, shims.

  14. Development of methodology for the synthesis of poly(lactic acid-co-glycolic acid) for use in the production of radioactive sources; Desenvolvimento da metodologia para sintese do poli(acido latico-co-acido glicolico) para utilizacao na producao de fontes radioativas

    Energy Technology Data Exchange (ETDEWEB)

    Peleias Junior, Fernando dos Santos

    2013-07-01

    According to World Health Organization (WHO), cancer is a leading cause of death worldwide. Prostate cancer is the second most common cancer in men. A method of radiotherapy which has been extensively used is brachytherapy, where radioactive seeds are placed inside the area requiring treatment. Iodine-125 seeds can be placed loose or stranded in bioabsorbable polymers. Stranded seeds show some advantages, since they reduce the rate of seed migration, an event that could affect the dosimetry of the prostate and cause unnecessary damage to healthy tissues or organs. For Iodine-125 stranded seeds, polyglactin 910 (poly(lactic-co-glycolic acid)) (PLGA), with a coverage of polyglactin 370 (Vicryl Registered-Sign ) is used. It was purposed in this dissertation, the study and development of the synthesis methodology for PLGA via ring-opening polymerization, as well as its characterization, with the objective of using the synthesized material to manufacture a material similar to RAPID Strand{sub Registered-Sign }. The results obtained show that it was possible to determine the optimal reaction parameters (time and temperature) for PLGA in 80/20 (lactide/glycolide) ratio. Using a temperature of 110 Degree-Sign C and reaction time of 24h, a yield of 86% was obtained, and increasing the reaction time to 72 hours, the yield was higher than 90%. The molecular mass values obtained from the samples are still very low compared to those obtained by other authors in the literature (about 20%). Failures in the sealing of vials, leaving them vulnerable to moisture and oxygen, or lack of an efficient stirring system might be possible explanations for these results. A suitable chemical reactor could solve the problem. Regarding polymer characterization, all techniques used not only confirmed the expected structure of the polymer, but also showed the highest proportion of lactide units compared to to glycolide units. (author)

  15. Methodology study for fixation of radioactive iodine in polymeric substrate for brachytherapy sources

    International Nuclear Information System (INIS)

    Rodrigues, Bruna T.; Rostelato, Maria Elisa C.M.; Souza, Carla D.; Tiezzi, Rodrigo; Souza, Daiane B. de; Benega, Marcos A.G.; Souza, Anderson S. de; Peleias Junior, Fernando S.; Zeituni, Calos A.; Fernandes, Vagner; Melo, Emerson Ronaldo de; Camargo, Anderson Rogerio de

    2015-01-01

    Cancer is now the second leading cause of death by disease in several countries, including Brazil. Prostate cancer is the most common among men. Brachytherapy is a modality of radiotherapy in which radioactive seeds are placed inside or in contact with the organ to be treated. The most widely used radioisotope in prostate brachytherapy is Iodine-125 which is presented fixated on a silver substrate that is subsequently placed inside a titanium capsule. A large dose of radiation is released only in the targeted tumor protecting healthy surrounding tissues. The technique requires the application of 80 - 120 seeds per patient. The implants of seeds have low impact and non-surgical procedures. Most patients can return to normal life within three days with little or no pain. This work proposes an alternative to the seeds that have already been developed, in order to reduce the cost by obtaining a better efficiency on fixing the radioactive iodine onto the epoxy resin. Methods have been developed to perform the fixation of Iodine-125 onto polymeric substrates. The parameters analyzed were the immersion time, type of static or dynamic reaction, concentration of the adsorption solution, the specific activity of the radioactive source, the need for carrier and chemical form of the radioactive Iodine. These experiments defined the most effective method to fixate the Iodine onto the polymeric material (epoxy resin), the Iodine activity in the polymeric substrate, the activity of the distribution of variation in a plot of polymeric cores and the efficiency of the epoxy resin to seal the seed. (author)

  16. Methodology study for fixation of radioactive iodine in polymeric substrate for brachytherapy sources

    Energy Technology Data Exchange (ETDEWEB)

    Rodrigues, Bruna T.; Rostelato, Maria Elisa C.M.; Souza, Carla D.; Tiezzi, Rodrigo; Souza, Daiane B. de; Benega, Marcos A.G.; Souza, Anderson S. de; Peleias Junior, Fernando S.; Zeituni, Calos A.; Fernandes, Vagner; Melo, Emerson Ronaldo de; Camargo, Anderson Rogerio de, E-mail: bteigarodrigues@gmail.com [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2015-07-01

    Cancer is now the second leading cause of death by disease in several countries, including Brazil. Prostate cancer is the most common among men. Brachytherapy is a modality of radiotherapy in which radioactive seeds are placed inside or in contact with the organ to be treated. The most widely used radioisotope in prostate brachytherapy is Iodine-125 which is presented fixated on a silver substrate that is subsequently placed inside a titanium capsule. A large dose of radiation is released only in the targeted tumor protecting healthy surrounding tissues. The technique requires the application of 80 - 120 seeds per patient. The implants of seeds have low impact and non-surgical procedures. Most patients can return to normal life within three days with little or no pain. This work proposes an alternative to the seeds that have already been developed, in order to reduce the cost by obtaining a better efficiency on fixing the radioactive iodine onto the epoxy resin. Methods have been developed to perform the fixation of Iodine-125 onto polymeric substrates. The parameters analyzed were the immersion time, type of static or dynamic reaction, concentration of the adsorption solution, the specific activity of the radioactive source, the need for carrier and chemical form of the radioactive Iodine. These experiments defined the most effective method to fixate the Iodine onto the polymeric material (epoxy resin), the Iodine activity in the polymeric substrate, the activity of the distribution of variation in a plot of polymeric cores and the efficiency of the epoxy resin to seal the seed. (author)

  17. Development of methodology for the synthesis of poly(lactic acid-co-glycolic acid) for use in the production of radioactive sources

    International Nuclear Information System (INIS)

    Peleias Junior, Fernando dos Santos

    2013-01-01

    According to World Health Organization (WHO), cancer is a leading cause of death worldwide. Prostate cancer is the second most common cancer in men. A method of radiotherapy which has been extensively used is brachytherapy, where radioactive seeds are placed inside the area requiring treatment. Iodine-125 seeds can be placed loose or stranded in bioabsorbable polymers. Stranded seeds show some advantages, since they reduce the rate of seed migration, an event that could affect the dosimetry of the prostate and cause unnecessary damage to healthy tissues or organs. For Iodine-125 stranded seeds, polyglactin 910 (poly(lactic-co-glycolic acid)) (PLGA), with a coverage of polyglactin 370 (Vicryl ®) is used. It was purposed in this dissertation, the study and development of the synthesis methodology for PLGA via ring-opening polymerization, as well as its characterization, with the objective of using the synthesized material to manufacture a material similar to RAPID Strand ® . The results obtained show that it was possible to determine the optimal reaction parameters (time and temperature) for PLGA in 80/20 (lactide/glycolide) ratio. Using a temperature of 110 ° C and reaction time of 24h, a yield of 86% was obtained, and increasing the reaction time to 72 hours, the yield was higher than 90%. The molecular mass values obtained from the samples are still very low compared to those obtained by other authors in the literature (about 20%). Failures in the sealing of vials, leaving them vulnerable to moisture and oxygen, or lack of an efficient stirring system might be possible explanations for these results. A suitable chemical reactor could solve the problem. Regarding polymer characterization, all techniques used not only confirmed the expected structure of the polymer, but also showed the highest proportion of lactide units compared to to glycolide units. (author)

  18. Enhanced sealing project (ESP): evolution of a full-sized concrete and bentonite shaft seal

    International Nuclear Information System (INIS)

    Dixon, D.A.; Priyanto, D.G.; Martino, J.B.; De Combarieu, M.; Johansson, R.; Korkeakoski, P.; Villagran, J.

    2012-01-01

    Document available in extended abstract form only. A full-scale shaft seal was designed and installed in the 5-m-diameter access shaft at Atomic Energy of Canada's (AECL's) Underground Research Laboratory (URL) at the point where he shaft intersects an ancient water-bearing, low-angle thrust fault in granitic rock. The seal, part of the permanent closure of the URL, consists of a 6-m-thick bentonite-based component sandwiched between 3-m-thick upper and lower, 3-m-thick concrete components. The bentonite-based component spans the fracture zone and extends approximately 1 m beyond the maximum identified extent of the fracture. This design was adopted in order to limit water from the deeper, saline regions mixing with the fresher, near-surface groundwater regime. The concrete components provide the mechanical confinement and an in situ compacted 40/60 mixture of bentonite clay and quartz sand provides the sealing component. Construction of the shaft seal was done as part of Canada's Nuclear Legacies Liability Program. However, monitoring the seal evolution was not part of the decommissioning program's mandate. In addition to accomplishing the permanent closure of the URL, this seal's construction provides a unique opportunity to instrument and monitor the evolution of a full-scale shaft seal as well as the recovery of the regional groundwater regime as the facility passively floods above the seal. A jointly funded monitoring project was developed by NWMO (Canada), SKB (Sweden), Posiva (Finland) and ANDRA (France) and since mid 2009 the thermal, hydraulic and mechanical evolution of the seal has been constantly monitored. The evolution of the type of seal being monitored in the ESP is of relevance to repository closure planning, gaining confidence in the functionality of shaft seals. Although constructed in a crystalline rock medium, the results of the ESP are expected to be relevant to the performance of seals in a variety of host rock types. The shaft seal has been

  19. Manifold seal structure for fuel cell stack

    Science.gov (United States)

    Collins, William P.

    1988-01-01

    The seal between the sides of a fuel cell stack and the gas manifolds is improved by adding a mechanical interlock between the adhesive sealing strip and the abutting surface of the manifolds. The adhesive is a material which can flow to some extent when under compression, and the mechanical interlock is formed providing small openings in the portion of the manifold which abuts the adhesive strip. When the manifolds are pressed against the adhesive strips, the latter will flow into and through the manifold openings to form buttons or ribs which mechanically interlock with the manifolds. These buttons or ribs increase the bond between the manifolds and adhesive, which previously relied solely on the adhesive nature of the adhesive.

  20. Low temperature sealing capabilities of fluoroelastomers

    Energy Technology Data Exchange (ETDEWEB)

    Stevens, D.D.; Thomas, E.W.; Brown, J.H.; Revolta, W.N.K.

    1991-10-01

    The purpose of this article is to examine some traditional rubber methods of measuring low temperature properties and compare those results to a test designed to evaluate the low temperature static sealing of o-rings. Testing is performed on a variety of fluoroelastomers to document differences and establish trends. By evaluating the performance of various fluoroelastomers in a practical low temperature o-ring test, the design engineer may gain a better understanding of the low temperature sealing capabilities of these polymers. Although the test results disclosed in this article are of short duration, it is the intention of the authors to evaluate the effects of longer term compressive deformation, stress relaxation and hot/cold cycling with the static o-ring test device in future work.

  1. Glass-ceramic composition for hermetic seals

    International Nuclear Information System (INIS)

    Ballard, C.P. Jr.

    1979-01-01

    The invention relates to a glass-ceramic composition having a high fracture strength adaptable for hermetically sealing to chromium bearing iron or nickel base alloys at temperatures of between about 950 0 C to about 1100 0 C to form a hermetically sealed insulator body, comprising from about 55 to about 65 weight percent SiO 2 , from about 0 to about 5 weight percent Al 2 O 3 , from about 6 to about 11 weight % Li 2 O, from about 25 to about 32 weight percent BaO, from about 0.5 to about 1.0 weight percent CoO and from about 1.5 to about 3.5 weight percent P 2 O 5

  2. Nanocrystalline diamond coatings for mechanical seals applications.

    Science.gov (United States)

    Santos, J A; Neto, V F; Ruch, D; Grácio, J

    2012-08-01

    A mechanical seal is a type of seal used in rotating equipment, such as pumps and compressors. It consists of a mechanism that assists the connection of the rotating shaft to the housings of the equipments, preventing leakage or avoiding contamination. A common cause of failure of these devices is end face wear out, thus the use of a hard, smooth and wear resistant coating such as nanocrystalline diamond would be of great importance to improve their working performance and increase their lifetime. In this paper, different diamond coatings were deposited by the HFCVD process, using different deposition conditions. Additionally, the as-grown films were characterized for, quality, morphology and microstructure using scanning electron microscopy (SEM) and Raman spectroscopy. The topography and the roughness of the films were characterized by atomic force microscopy (AFM).

  3. Glass-ceramic composition for hermetic seals

    Science.gov (United States)

    Ballard, Jr., Clifford P.

    1979-01-01

    The invention relates to a glass-ceramic composition having a high fracture strength adaptable for hermetically sealing to chromium bearing iron or nickel base alloys at temperatures of between about 950.degree. C to about 1100.degree. C to form a hermetically sealed insulator body, comprising from about 55 to about 65 weight percent SiO.sub.2, from about 0 to about 5 weight percent Al.sub.2 O.sub.3, from about 6 to about 11 weight % Li.sub.2 O, from about 25 to about 32 weight percent BaO, from about 0.5 to about 1.0 weight percent CoO and from about 1.5 to about 3.5 weight percent P.sub.2 O.sub.5.

  4. Genetics and Forest Seed Handling

    DEFF Research Database (Denmark)

    Schmidt, Lars Holger

    2016-01-01

    High genetic quality seed is obtained from seed sources that match the planting site, have a good outcrossing rate, and are superior in some desirable characters. Non-degraded natural forests and plantations may be used as untested seed sources, which can sometimes be managed to promote outbreeding...... and increase seed production. Planted seed orchards aim at capturing large genetic variation and are planted in a design that facilitates genetic evaluation and promotes outbred seed production. Good seed production relies upon success of the whole range of reproductive events from flower differentiation...

  5. Sealing nuclear graphite with pyrolytic carbon

    International Nuclear Information System (INIS)

    Feng, Shanglei; Xu, Li; Li, Li; Bai, Shuo; Yang, Xinmei; Zhou, Xingtai

    2013-01-01

    Pyrolytic carbon (PyC) coatings were deposited on IG-110 nuclear graphite by thermal decomposition of methane at ∼1830 °C. The PyC coatings are anisotropic and airtight enough to protect IG-110 nuclear graphite against the permeation of molten fluoride salts and the diffusion of gases. The investigations indicate that the sealing nuclear graphite with PyC coating is a promising method for its application in Molten Salt Reactor (MSR)

  6. Annular Pressure Seals and Hydrostatic Bearings

    Science.gov (United States)

    2006-11-01

    scale). The equation below presents a close form expression for estimation of the added mass coefficient (MXX) in a seal or squeeze film damper [14...Arauz & L. San Andrés, “ASME Journal of Tribology, 120, pp. 221-233, 1998. [14] Squeeze Film Dampers : Operation, Models and Technical Issues, L. San...fluid film bearing technology with very low number of parts and no DN limit operation. Details on the bulk- flow analysis of turbulent flow

  7. Remote Monitoring of Instrumentation in Sealed Compartments

    International Nuclear Information System (INIS)

    Landron, Clinton; Moser, John C.

    1999-01-01

    The Instrumentation and Telemetry Departments at Sandia National Laboratories have been exploring the instrumentation of sealed canisters where the flight application will not tolerate either the presence of a chemical power source or penetration by power supply wires. This paper will describe the application of a low power micro-controller based instrumentation system that uses magnetic coupling for both power and data to support a flight application

  8. Control of sealed radioactive sources in Peru

    International Nuclear Information System (INIS)

    Ramirez Quijada, R.

    2001-01-01

    The paper describes the inventory of radioactive sources in Peru and assesses the control. Three groups of source conditions are established: controlled sources, known sources, and lost and orphan sources. The potential risk, described as not significant, for producing accidents is established and the needed measures are discussed. The paper concludes that, while the control on sealed sources is good, there is still room for improvement. (author)

  9. What Are Chia Seeds?

    Science.gov (United States)

    ... help improve cardiovascular risk factors such as lowering cholesterol, triglycerides and blood pressure. However, there are not ... ground or whole chia seeds on cereal, rice, yogurt or vegetables. In Mexico, a dish called chia ...

  10. Qualification tests for 192Ir sealed sources

    Science.gov (United States)

    Iancso, Georgeta; Iliescu, Elena; Iancu, Rodica

    2013-12-01

    This paper describes the results of qualification tests for 192Ir sealed sources, available in Testing and Nuclear Expertise Laboratory of National Institute for Physics and Nuclear Engineering "Horia Hulubei" (I.F.I.N.-HH), Romania. These sources had to be produced in I.F.I.N.-HH and were tested in order to obtain the authorization from The National Commission for Nuclear Activities Control (CNCAN). The sources are used for gammagraphy procedures or in gammadefectoscopy equipments. Tests, measurement methods and equipments used, comply with CNCAN, AIEA and International Quality Standards and regulations. The qualification tests are: 1. Radiological tests and measurements: dose equivalent rate at 1 m; tightness; dose equivalent rate at the surface of the transport and storage container; external unfixed contamination of the container surface. 2. Mechanical and climatic tests: thermal shock; external pressure; mechanic shock; vibrations; boring; thermal conditions for storage and transportation. Passing all tests, it was obtained the Radiological Security Authorization for producing the 192Ir sealed sources. Now IFIN-HH can meet many demands for this sealed sources, as the only manufacturer in Romania.

  11. Sealing versus Nonsealing: Cost-benefit analysis

    Directory of Open Access Journals (Sweden)

    Anshula N Deshpande

    2016-01-01

    Full Text Available Dental caries still remains the second most prevalent disease after common cold, out of which occlusal caries is the most profound one. In India, more than 40% of children are found to be affected by dental caries. Occlusal surfaces of the teeth are most susceptible sites for caries development due to their morphology. They are least benefited from fluoride application. Various efforts have been made by the preventive means to decline the rate of caries, one of which being sealant application. Sealants have come into existence long back since 1971 when first pit and fissure sealant Nuva-Caulk came into existence. There have been piles of literature stating the benefits that arrive from sealing the teeth. However, one crucial point that is being missed most of the times is the cost-effectiveness of the sealant. There are various schools of thoughts, regarding this that is controversial ones. Some of the analysts believe that always sealing may be a bit costlier, but it reduces subsequent dental treatments and hence saves money as well as time. However, some believe that why to unnecessarily seal the teeth in all cases even when the child is not at a risk to develop caries. Hence, we need to foresee both the sides of equation. For best clinical practice and decision-making, we need to have a balance of best evidence, clinical judgment, and the most important, patient needs and preferences.

  12. ESDRED Temporary Sealing Technology Final Technical Report

    Energy Technology Data Exchange (ETDEWEB)

    Alonso, J.; Garcia-Sineriz, J. L.; Barcena, I.; Alonso, M. C.; Fernandez Luco, L.; Garcia, J. L.; Fries, T.; Pettersson, S.; Boden, A.; Salo, J. P.

    2009-07-01

    The work in the ESDRED In te grated Project Module 4, Temporary Sealing (using low pH cement) Technology, consisted first of designing a low pH cement formulation and then of preparing several concrete designs suitable for the construction of sealing plugs and for rock support using shot crete techniques. Regarding sealing plugs, a short plug was constructed at Aspo in Sweden and it was very quickly loaded to failure i.e. slippage by applying water pressure to one face. A second, full scale plug was subsequently constructed at Grimsel test site in Switzerland. It was loaded using the swelling pressure created by bentonite blocks which were artificially hydrated. At time of writing the targeted pressure on the plug was not reached. As the saturation of the bentonite is taking longer than expected the partners involved agreed to continue with the saturation of the bentonite blocks and the related data monitoring beyond the ESDRED Project. The studies on low-pH shot crete for rock sup port were based on available recipes of low-pH concrete mixtures for use in a repository. Pilot and full scale tests were carried out in Sweden and in Switzerland. (Author) 5 refs.

  13. One-piece modified gasket seal technique.

    Science.gov (United States)

    Wessell, Aaron; Singh, Ameet; Litvack, Zachary

    2013-10-01

    Objectives Review the effectiveness of a modified gasket seal technique utilizing a porous high-density polyethylene plate/rectus sheath fascia construct without fat grafting for primary closure of anterior defects following endoscopic skull base surgery. Design Retrospective review (2011-2012). Setting Single academic medical center. Methods A retrospective review of five patients who underwent expanded endoscopic endonasal surgery for various pathologies (two craniopharyngiomas, two tuberculum meningiomas, and one planum meningioma) was performed. Skull base closure was performed using a one-piece modified gasket seal technique. Primary outcome measures included postoperative cerebrospinal fluid (CSF) leaks and donor site morbidity. Results There were no postoperative CSF leaks. Two patients experienced aseptic meningitis treated with a 14-day course of steroids. Two patients experienced new postoperative chronic/recurrent sinusitis treated with oral antibiotics and topical nasal therapy. There was no donor site morbidity such as infection, hematoma, or hernias. Conclusions The one-piece modified gasket-seal closure is a safe and effective method for reconstruction of endonasal defects of the anterior skull base. Rectus sheath fascia is an appropriate dural substitute for free tissue grafting with low donor site morbidity. The construction of the one-piece graft significantly decreases operative time and lowers the learning curve for multilayered closure.

  14. Management of disused plutonium sealed sources

    Energy Technology Data Exchange (ETDEWEB)

    Whitworth, Julia Rose [Los Alamos National Laboratory; Pearson, Michael W [Los Alamos National Laboratory; Abeyta, Cristy [Los Alamos National Laboratory

    2010-01-01

    The Global Threat Reduction Initiative's (GTRI) Offsite Source Recovery Project (OSRP) has been recovering excess and unwanted radioactive sealed sources since 1999, including more than 2,400 Plutonium (Pu)-238 sealed sources and 653 Pu-239-bearing sources that represent more than 10% of the total sources recovered by GTRI/OSRP to date. These sources have been recovered from hundreds of sites within the United States (US) and around the world. OSRP grew out of early efforts at the Los Alamos National Laboratory (LANL) to recover and disposition excess Plutonium-239 (Pu-239) sealed sources that were distributed in the 1960s and 1970s under the Atoms for Peace Program, a loan-lease program that serviced 31 countries, as well as domestic users. In the conduct of these recovery operations, GTRI/OSRP has been required to solve problems related to knowledge-of-inventory, packaging and transportation of fissile and heat-source materials, transfer of ownership, storage of special nuclear material (SNM) both at US Department of Energy (DOE) facilities and commercially, and disposal. Unique issues associated with repatriation from foreign countries, including end user agreements required by some European countries and denials of shipment, will also be discussed.

  15. Creep as a mechanism for sealing amalgams.

    Science.gov (United States)

    Osborne, John W

    2006-01-01

    Dental amalgam seals itself over time. The reduction of microleakage in amalgam restorations has been explained by corrosion products filling in the interface gap between amalgam and tooth structure in order to seal the restoration interface. This concept has been widely accepted; yet, curiously, there is little research supporting this theory. The creep mechanism may be a plausible alternative to explaining why microleakage is reduced over time in amalgam restorations. Amalgam restorations are confined to the fixed space of the cavity preparation; expansion of the amalgam through internal phase changes in this confined area must be relieved. The resultant creep-expansion of the amalgam restoration fills in the tooth/amalgam interface gap. Once the interfacial gap is filled and amalgam has made intimate contact with the cavity wall, the dental amalgam slides along the tooth preparation plane as predicted by classic metallurgical studies. The results of the creep of amalgam have been observed clinically as the extrusion of amalgam from the cavity preparation. This explanation for amalgam sealing the tooth/amalgam gap fits many clinical observations and certain research data.

  16. CENTRIFUGAL PUMP AND SHAFT SEALING MEANS

    Science.gov (United States)

    Rushing, F.C.

    1960-09-01

    A description is given of sealing means between a hollow rotatable shaft and a stationary member surrounding the shaft which defines therewith a sealing space of annular cross-section, comprising a plurality of axially spaced rings held against seats by ring springs which serve to subdivide the sealing space- into a plurality of zones. Process gas introduced into the hollow shaft through a port communicating with a centrally located zone which iu turn communicates with a bore in the sleeve, is removed from the shaft through a second port communicating with an adjacent central zone and discharged through a second bore. A sealant gas is supplied to an end zone under a pressure sufficient to cause it to flow axially into adjacent zones and then maintained at a lower pressure than either the sealant gas source or the process gas inlet zone, preventing the sealant gas from entering the shaft and allowing gases leaking into the sealant gas to be withdrawn and led to a separator.

  17. A role for seed storage proteins in Arabidopsis seed longevity.

    Science.gov (United States)

    Nguyen, Thu-Phuong; Cueff, Gwendal; Hegedus, Dwayne D; Rajjou, Loïc; Bentsink, Leónie

    2015-10-01

    Proteomics approaches have been a useful tool for determining the biological roles and functions of individual proteins and identifying the molecular mechanisms that govern seed germination, vigour and viability in response to ageing. In this work the dry seed proteome of four Arabidopsis thaliana genotypes, that carry introgression fragments at the position of seed longevity quantitative trait loci and as a result display different levels of seed longevity, was investigated. Seeds at two physiological states, after-ripened seeds that had the full germination ability and aged (stored) seeds of which the germination ability was severely reduced, were compared. Aged dry seed proteomes were markedly different from the after-ripened and reflected the seed longevity level of the four genotypes, despite the fact that dry seeds are metabolically quiescent. Results confirmed the role of antioxidant systems, notably vitamin E, and indicated that protection and maintenance of the translation machinery and energy pathways are essential for seed longevity. Moreover, a new role for seed storage proteins (SSPs) was identified in dry seeds during ageing. Cruciferins (CRUs) are the most abundant SSPs in Arabidopsis and seeds of a triple mutant for three CRU isoforms (crua crub cruc) were more sensitive to artificial ageing and their seed proteins were highly oxidized compared with wild-type seeds. These results confirm that oxidation is involved in seed deterioration and that SSPs buffer the seed from oxidative stress, thus protecting important proteins required for seed germination and seedling formation. © The Author 2015. Published by Oxford University Press on behalf of the Society for Experimental Biology.

  18. Storage of sunflower seeds

    Directory of Open Access Journals (Sweden)

    Denise de Castro Lima

    Full Text Available The sunflower is among the top five crops in the world for the production of edible vegetable oil. The species displays rustic behavior, with an excellent edaphic and climatic adaptability index, being able to be cultivated throughout Brazil. Seed quality is the key to increasing production and productivity in the sunflower. The objective of this work was to monitor the viability of sunflower seeds with a view to their conservation when stored in different environments and packaging. The seeds were packed in paper bags, multilayered paper, black polyethylene and PET bottles; and stored for a period of twelve months in the following environments: dry cold room (10 ºC and 55% RH, the ambient conditions of Fortaleza, Ceará, Brazil (30-32 ºC and 75% RH, refrigerator (4 ºC and 38-43% RH and freezer (-20 ºC. Every three months, the water content of the seeds was determined and germination, accelerated ageing, speed of emergence index, and seedling dry weight were evaluated. The experimental design was completely randomized, in a scheme of split-lots, with four replications. It can be concluded that the natural environment is not suitable for the storage of sunflower seeds. Sunflower seeds remain viable for 12 months when stored in a dry cold room, refrigerator or freezer, irrespective of the type of packaging used.

  19. Innovative Seals for Solid Oxide Fuel Cells (SOFC)

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Raj

    2008-06-30

    A functioning SOFC requires different type of seals such as metal-metal, metal-ceramic, and ceramic-ceramic. These seals must function at high temperatures between 600--900{sup o}C and in oxidizing and reducing environments of the fuels and air. Among the different type of seals, the metal-metal seals can be readily fabricated using metal joining, soldering, and brazing techniques. However, the metal-ceramic and ceramic-ceramic seals require significant research and development because the brittle nature of ceramics/glasses can lead to fracture and loss of seal integrity and functionality. Consequently, any seals involving ceramics/glasses require a significant attention and technology development for reliable SOFC operation. This final report is prepared to describe the progress made in the program on the needs, approaches, and performance of high temperature seals for SOFC. In particular, a new concept of self-healing glass seals is pursued for making seals between metal-ceramic material combinations, including some with a significant expansion mismatch.

  20. Fusion Engineering Device frame seal welder and cutter

    International Nuclear Information System (INIS)

    Watts, K.D.; Williams, S.A.; Longhurst, G.R.; McPherson, R.S.; Masson, L.S.

    1981-10-01

    The Fusion Engineering Device (FED) is being designed in a torus shape using ten removable segments to form the torus geometry. The torus consists of a frame and ten shield assemblies which fit into the frame. It is necessary to seal the shield segment to the frame for the assembly to sustain an internal vacuum. Designs for the seal, the welder to weld the seal in place, the cutter to remove the seal, and the handling fixture for seal installation and removal are presented. The concept for the seal installation is novel in that precise alignment of the seal to the torus frame and shield assemblies is not required. Vacuum handling technology is used for handling the three story tall, twelve foot wide, fragile, relatively light weight seal. The welder and cutter assemblies track off the seal handling fixture, eliminating the need for complex rails on each of the shield segments. The entire seal installation and removal system has been designed for remote operation