Organic moderator-coolant in-pile irradiation loop for the MIT nuclear reactor : October 1, 1958 to October 1, 1959

Includes bibliographical references (leaf 34)First annual report; to October 1, 1958 to October 1, 1959Work performed under contract with Atomics International of North American Aviation, Inc. N9-S-514Division of Sponsored Research Project no. 8091Atomic Energy Commission contract no. AT(10-1)-106

How does iron interact with sporopollenin exine capsules? An X-ray absorption study including microfocus XANES and XRF imaging

Sporopollenin exine capsules (SECs) derived from plant spores and pollen grains have been proposed as adsorption, remediation and drug delivery agents. Despite many studies there is scant structural data available. This X-ray absorption investigation represents the first direct structural data on the interaction of metals with SECs and allows elucidation of their structure–property relationships. Fe K-edge XANES and EXAFS data have shown that the iron local environment in SECs (derived from Lycopodium clavatum) reacted with aqueous ferric chloride solutions is similar to that of ferrihydrite (FeOOH) and by implication ferritin. Fe Kα XRF micro-focus experiments show that there is a poor correlation between the iron distribution and the underlying SEC structure indicating that the SEC is coated in the FeOOH material. In contrast, the Fe Kα XRF micro-focus experiments on SECs reacted with aqueous ferrous chloride solutions show that there is a very high correlation between the iron distribution and the SEC structure, indicating a much more specific form of interaction of the iron with the SEC surface functional groups. Fe K-edge XANES and EXAFS data show that the FeII can be easily oxidised to give a structure similar to, but not identical to that in the FeIII case, and that even if anaerobic conditions are used there is still partial oxidation to FeIII

Radiopyrolysis

Statement of responsibility on title-page reads: E.A. Mason, T.H. Timmins, D.T. Morgan, and W.N. Bley"Issued: October 1966.""MIT-334-70 Reactor Technology."Also issued by T.H. Timmins and supervised by E.A. Mason as an Sc. D. thesis , Massachusetts Institute of Technology, Dept. of Nuclear Engineering, 1967Includes bibliographical references (pages A6.1-A6.7)MIT DSR Project no. 79819Work performed for the Savannah River Operations Office, U.S. Atomic Energy Commission under Contract no. AT(38-1)-33

Managing inventory and production capacity in start-up firms

We consider the problem of managing inventory and production capacity in a start-up manufacturing firm with the objective of maximising the probability of the firm surviving as well as the more common objective of maximising profit. Using Markov decision process models, we characterise and compare the form of optimal policies under the two objectives. This analysis shows the importance of coordination in the management of inventory and production capacity. The analysis also reveals that a start-up firm seeking to maximise its chance of survival will often choose to keep production capacity significantly below the profit-maximising level for a considerable time. This insight helps us to explain the seemingly cautious policies adopted by a real start-up manufacturing firm

Benefits of hybrid lateral transshipments in multi-item inventory systems under periodic replenishment

Lateral transshipments are a method of responding to shortages of stock in a network of inventory-holding locations. Conventional reactive approaches only seek to meet immediate shortages. The study proposes hybrid transshipments which exploit economies of scale by moving additional stock between locations to prevent future shortages in addition to meeting immediate ones. The setting considered is motivated by retailers who operate networks of outlets supplying car parts via a system of periodic replenishment. It is novel in allowing non-stationary stochastic demand and general patterns of dependence between multiple item types. The generality of our work makes it widely applicable. We develop an easy-to-compute quasi-myopic heuristic for determining how hybrid transshipments should be made. We obtain simple characterizations of the heuristic and demonstrate its strong cost performance in both small and large networks in an extensive numerical study