MODIFICATION
66 -- Bismuth Block for filter material - Amendment 1
- Notice Date
- 1/14/2011
- Notice Type
- Modification/Amendment
- NAICS
- 325998
— All Other Miscellaneous Chemical Product and Preparation Manufacturing
- Contracting Office
- Department of Commerce, National Institute of Standards and Technology (NIST), Acquisition Management Division, 100 Bureau Drive, Building 301, Room B129, Mail Stop 1640, Gaithersburg, Maryland, 20899-1640
- ZIP Code
- 20899-1640
- Solicitation Number
- SB1341-11-RQ-0071
- Archive Date
- 2/28/2011
- Point of Contact
- Joni L Laster, Phone: 301-975-8397, Todd D Hill, Phone: 301-975-8802
- E-Mail Address
-
joni.laster@nist.gov, todd.hill@nist.gov
(joni.laster@nist.gov, todd.hill@nist.gov)
- Small Business Set-Aside
- Total Small Business
- Description
- Amendment I Drawing 044-0002-2 The above solicitation is hereby amended to incorporate quantity and technical changes to Line Item 0001 and include revised drawing (044-0002-2) drawing 044-002 is hereby deleted. The due date/time, January 27, 2011 @ 3pm EST remains unchanged. The quantity and technical changes for Line Item 0001 are as follows: FROM: The National Institute of Standards and Technology (NIST) has a requirement for a block of pure bismuth to be used as filter material. The Department of Commerce and the National Institute of Standards and Technology (NIST) have developed a major national facility for neutron scattering. This project provides for over fifteen unique instrument stations for use by national and international researchers for materials research. In addition, instruments are also provided for fundamental physics research, neutron interferometry, and neutron optics. To remain at the forefront of science, the NIST Center for Neutron Research (NCNR) is continuously developing new and improved instruments for neutron scattering. NIST requires an accurately dimensioned rectangular block made from pure, single-crystal bismuth. This bismuth block shall be cryogenically cooled and shall be located upstream of a new instrument named the Chromatic Analysis Neutron Diffractometer or Reflectometer (CANDOR) and shall be used as a gamma ray filter for CANDOR. This block of pure bismuth shall be made up of several large crystals and shall be used to filter out unwanted gamma rays from the neutron beam. Single-crystal bismuth is known to be affective in attenuating gamma rays whose high energy can distort the purity of the thermal neutrons. Single crystal and large crystal bismuth has much higher transmission of neutrons between.4nm and.8nm than small crystal (fine grained) polycrystalline due to the minimization of Bragg scattering by reducing the number of individual crystals. Cooling the bismuth has the effect of making the crystals become nearly transparent to thermal neutrons and remain nearly opaque to high energy gamma rays. All responsible quoters shall provide a quotation for the following line item: LINE ITEM 0001: Quantity one (1) each, bismuth block (that shall be made up of several large single crystals), which satisfies the material and end product specifications defined herein to achieve the desired performance as a gamma ray filter. (A) Bulk Materials Specification: CAS No.: The bismuth used shall be in accordance with the Chemical Abstracts Service (CAS) number 7440-69-9. Purity: The bismuth must be 99.999% pure. (B) Crystal End Product Specification: Crystal Characteristics: One structure that is composed of several large crystals shall be grown, that will be irregularly shaped, eg some round and some rectangular. The minimum dimension of any irregular shape shall be 25mm. Process Characteristics: After the structure of large crystals has been grown, it shall be cut, machined, fine ground and etched (to remove the deformed layer and reveal crystal boundaries) to the Physical Dimensions described in Section C. Density: The density of the end product shall be within 0.5% of the theoretical density of bismuth to ensure that there are not significant voids in the material. The room temperature density of bismuth is 9.78 g/cm³. Physical Characteristics: The following specifications ensure that the bismuth block can be mounted as a mechanical body without shedding toxic parts: 1. Shear Modulus - 1,700 kpsi 2. Young's Modulus - 4,500 kpsi 3. No cracks permissible 4. Largest dimension of corner or edge chip < 2mm 5. Number of chips allowable with size less than 2mm, 6-8 per piece ( C) Physical Dimensions: The material shall be delivered as one accurately dimensioned block. The physical dimensions, tolerances and surface finish are specified on the attached drawing 044-0002. TO: The National Institute of Standards and Technology (NIST) has a requirement for two blocks of pure bismuth to be used as filter material. The Department of Commerce and the National Institute of Standards and Technology (NIST) have developed a major national facility for neutron scattering. This project provides for over fifteen unique instrument stations for use by national and international researchers for materials research. In addition, instruments are also provided for fundamental physics research, neutron interferometry, and neutron optics. To remain at the forefront of science, the NIST Center for Neutron Research (NCNR) is continuously developing new and improved instruments for neutron scattering. NIST requires two accurately dimensioned, identical rectangular blocks made from pure, single-crystal bismuth. These bismuth blocks shall be cryogenically cooled and shall be located upstream of a new instrument named the Chromatic Analysis Neutron Diffractometer or Reflectometer (CANDOR) and shall be used as a gamma ray filter for CANDOR. These 2 blocks of pure bismuth shall be made up of several large crystals and shall be used to filter out unwanted gamma rays from the neutron beam. Single-crystal bismuth is known to be affective in attenuating gamma rays whose high energy can distort the purity of the thermal neutrons. Single crystal and large crystal bismuth has much higher transmission of neutrons between.4nm and.8nm than small crystal (fine grained) polycrystalline due to the minimization of Bragg scattering by reducing the number of individual crystals. Cooling the bismuth has the effect of making the crystals become nearly transparent to thermal neutrons and remain nearly opaque to high energy gamma rays. All responsible quoters shall provide a quotation for the following line item: LINE ITEM 0001: Quantity two (2), bismuth blocks (that shall be made up of several large single crystals), which satisfies the material and end product specifications defined herein to achieve the desired performance as a gamma ray filter. (A) Bulk Materials Specification: CAS No.: The bismuth used shall be in accordance with the Chemical Abstracts Service (CAS) number 7440-69-9. Purity: The bismuth must be 99.999% pure. (B) Crystal End Product Specification: Crystal Characteristics: Two structures that are composed of several large crystals shall be grown. These crystals will be irregularly shaped, eg some round and some rectangular,(Note: the average size of a crystal will be around 25mm but there is no minimum dimension because the shapes are too irregular). Process Characteristics: After the two blocks of large crystals have been grown, they shall be cut, machined, fine ground and etched (to remove the deformed layer and reveal crystal boundaries) to the Physical Dimensions described in Section C. Density: The density of the end product shall be within 0.5% of the theoretical density of bismuth to ensure that there are not significant voids in the material. The room temperature density of bismuth is 9.78 g/cm³. Physical Characteristics: The following specifications ensure that the bismuth blocks can be mounted as mechanical bodies without shedding toxic parts: 1. Shear Modulus - 1,700 kpsi 2. Young's Modulus - 4,500 kpsi 3. No cracks permissible 4. Largest dimension of corner or edge chip < 2mm 5. Number of chips allowable with size less than 2mm, 6-8 per piece ( C) Physical Dimensions: The material shall be delivered as two accurately dimensioned, identical blocks. The physical dimensions, tolerances and surface finish are specified on the attached drawing 044-0002-2.
- Web Link
-
FBO.gov Permalink
(https://www.fbo.gov/spg/DOC/NIST/AcAsD/SB1341-11-RQ-0071/listing.html)
- Place of Performance
- Address: 100 Bureau Drive, Gaithersburg, Maryland, 20899, United States
- Zip Code: 20899
- Zip Code: 20899
- Record
- SN02361171-W 20110116/110114234622-3fa4e2b76c0fff5097a97244bd3cb6ec (fbodaily.com)
- Source
-
FedBizOpps Link to This Notice
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