BINDER MODIFICATION AND DEVELOPMENT FOR BRIQUETTING STEEL MILL RESIDUES

Alternatives to the molasses-ordinary portland cement (OPC) binder as a binder for steel mill residues were extensively investigated. A large number of binder modifications were tested using a hand pelleting apparatus to identify effective compositions. The more effective compositions were evaluated in a series of three briquetting matrices using the Komarek press. Evaluations consisted of drop tests, compression tests of given and cured pellets, and tumble tests of cured pellets. Pyrolysis odor tests were performed to determine the effects of certain compositions on the disagreeable wet campfire odor produced during heating of the molasses--OPC briquettes. Several scanning electron microscope (SEM) morphology studies were conducted to examine the nature of structures formed during pelleting or briquetting

FINAL TOPICAL REPORT FOR NOVEL SYSTEMS SEQUESTERING AND UTILIZATION OF CO2

Atmospheric CO{sub 2} concentrations are increasing by about 0.5% each year, and there is serious concern that this will cause adverse climate change via the ''greenhouse effect.'' The principal sources of the increase are the utilization of fossil fuels and the deforestation of land. The capture of CO{sub 2} from flue gas or process streams has been demonstrated using chemical absorption with an ethanolamine solvent. However, the cost of releasing the CO{sub 2} by thermal stripping and recovering the solvent is very high, resulting in an energy penalty of 27% to 37 %, depending on the type of power plant (1). Alternatives that would result in energy penalties of 15% have been investigated. Sequestering schemes for CO{sub 2} produced from fossil fuels conversion to energy in utility plants could instead yield useful polymer products. Relatively concentrated CO{sub 2} by-product streams from fermentation of cellulose to fuel ethanol will also be available for conversion to useful polymers. As shown in Figure 1, this project offers two opportunities for mitigating the emission of CO{sub 2} to the atmosphere, depending on the source configuration and economic feasibility of the proposed processes: CO{sub 2} in a conventional utility-produced flue gas could be sequestered to form a reactive monomer using an amine (such as ethanolamine) that reacts with an aldehyde to form an amine intermediate, which subsequently copolymerizes with the CO{sub 2} to give a copolyurethane. Using a tertiary amine to trap the CO{sub 2} is also proposed. In this case the tertiary ammonium carbonate is reacted with the aldehyde to form the copolycarbonate, regenerating the tertiary amine. In an alternate scheme, a concentrated CO{sub 2} stream from an advanced energy system could be directly polymerized with aldehyde and catalyst to Polymer 2. Sources of concentrated CO{sub 2} include the water-gas shift reaction in an IGCC (integrated gasification combined-cycle) device, fermentation, a fuel cell anode gas, or oxygen-fired combustion. Significant sequestration of CO{sub 2} would be accomplished if large amounts could be efficiently and economically converted to stable and useful products that would pay for the processing. If the CO{sub 2} is stored rather than converted to a useful product, the cost of sequestering must be extremely low. If CO{sub 2} is to be utilized as a chemical feedstock, the allowable process cost can be higher, but only high-volume commodity chemical products could sequester a significant amount of CO{sub 2}. Large volumes of inexpensive CO{sub 2}-derived polymers could be utilized for enhanced oil recovery, structural thermoplastic resins, and ion-exchange applications. Economic success is better achieved with the availability of a very inexpensive aldehyde or derivative mine. To provide this component inexpensively, a novel photosystem is proposed such that CO{sub 2} is also converted to the desired copolymer feedstock

Subtask 1.16-Slow-Release Bioremediation Accelerators

Low-cost methods are needed to enhance various bioremediation technologies, from natural attenuation to heavily engineered remediation of subsurface hydrocarbon contamination. Many subsurface sites have insufficient quantities of nitrogen and phosphorus, resulting in poor bioactivity and increased remediation time and costs. The addition of conventional fertilizers can improve bioactivity, but often the nutrients dissolve quickly and migrate away from the contaminant zone before being utilized by the microbes. Through this project, conducted by the Energy & Environmental Research Center, polymers were developed that slowly release nitrogen and phosphorus into the subsurface. Conceptually, these polymers are designed to adhere to soil particles in the subsurface contamination zone where they slowly degrade and release nutrients over longer periods of time compared to conventional fertilizer applications. Tests conducted during this study indicate that some of the developed polymers have excellent potential to satisfy the microbial requirements for enhanced bioremediation

EFFECTS OF SODIUM AND CALCIUM IN LIGNITE ON THE PERFORMANCE OF ACTIVATED CARBON PRODUCTS

New federal drinking water regulations have been promulgated to restrict the levels of disinfection by-products (DBPs) in finished public water supplies. DBPs are suspected carcinogens and are formed when organic material is partially oxidized by disinfectants commonly used in the water treatment industry. Additional federal mandates are expected in the near future that will also affect public water suppliers with respect to DBPs. These new federal drinking water regulations may require public water suppliers to adjust treatment practices or incorporate additional treatment operations into their existing treatment trains. Many options have been identified, including membrane processes, granular activated carbon, powered activated carbon (PAC), enhanced coagulation and/or softening, and alternative disinfectants (e.g., chlorine dioxide, ozone, and chloramines). Of the processes being considered, PAC appears to offer an attractive benefit-to-cost advantage for many water treatment plants, particularly small systems (those serving fewer than 10,000 customers). PAC has traditionally been used by the water treatment industry for the removal of compounds contributing to taste and odor problems. PAC also has the potential to remove naturally occurring organic matter (NOM) from raw waters prior to disinfection, thus controlling the formation of regulated DBPs. Many small water systems are currently using PAC for taste and odor control and have the potential to use PAC for controlling DBPs. Activated carbons can be produced from a variety of raw materials, including wood, peat, coconut husks, and numerous types of coal. The Energy & Environmental Research Center (EERC) has been working on the development of a PAC product to remove NOM from surface water supplies to prevent the formation of carcinogenic DBPs during chlorination. During that study, the sodium and calcium content of the lignites showed a significant effect on the sorption capacity of the activated carbon product. As much as a 130% increase in the humic acid sorption capacity of a PAC produced from a high-sodium-content lignite was observed. We hypothesize that the sodium and calcium content of the coal plays a significant role in the development of pore structures and pore-size distribution, ultimately producing activated carbon products that have greater sorption capacity for specific contaminants, depending on molecular size

Megakaryocytes promote murine osteoblastic HSC niche expansion and stem cell engraftment after radioablative conditioning

Successful hematopoietic stem cell (HSC) transplantation requires donor HSC engraftment within specialized bone marrow microenvironments known as HSC niches. We have previously reported a profound remodeling of the endosteal osteoblastic HSC niche after total body irradiation (TBI), defined as relocalization of surviving megakaryocytes to the niche site and marked expansion of endosteal osteoblasts. We now demonstrate that host megakaryocytes function critically in expansion of the endosteal niche after preparative radioablation and in the engraftment of donor HSC. We show that TBI-induced migration of megakaryocytes to the endosteal niche depends on thrombopoietin signaling through the c-MPL receptor on megakaryocytes, as well as CD41 integrin-mediated adhesion. Moreover, niche osteoblast proliferation post-TBI required megakaryocyte-secreted platelet-derived growth factor-BB. Furthermore, blockade of c-MPL-dependent megakaryocyte migration and function after TBI resulted in a significant decrease in donor HSC engraftment in primary and competitive secondary transplantation assays. Finally, we administered thrombopoietin to mice beginning 5 days before marrow radioablation and ending 24 hours before transplant to enhance megakaryocyte function post-TBI, and found that this strategy significantly enhanced donor HSC engraftment, providing a rationale for improving hematopoietic recovery and perhaps overall outcome after clinical HSC transplantation.Successful hematopoietic stem cell (HSC) transplantation requires donor HSC engraftment within specialized bone marrow microenvironments known as HSC niches. We have previously reported a profound remodeling of the endosteal osteoblastic HSC niche after total body irradiation (TBI), defined as relocalization of surviving megakaryocytes to the niche site and marked expansion of endosteal osteoblasts. We now demonstrate that host megakaryocytes function critically in expansion of the endosteal niche after preparative radioablation and in the engraftment of donor HSC. We show that TBI-induced migration of megakaryocytes to the endosteal niche depends on thrombopoietin signaling through the c-MPL receptor on megakaryocytes, as well as CD41 integrin-mediated adhesion. Moreover, niche osteoblast proliferation post-TBI required megakaryocyte-secreted platelet-derived growth factor-BB. Furthermore, blockade of c-MPL-dependent megakaryocyte migration and function after TBI resulted in a significant decrease in donor HSC engraftment in primary and competitive secondary transplantation assays. Finally, we administered thrombopoietin to mice beginning 5 days before marrow radioablation and ending 24 hours before transplant to enhance megakaryocyte function post-TBI, and found that this strategy significantly enhanced donor HSC engraftment, providing a rationale for improving hematopoietic recovery and perhaps overall outcome after clinical HSC transplantation

A High-Rate, Heterogeneous Data Set from the Darpa Urban Challenge

This paper describes a data set collected by MIT’s autonomous vehicle Talos during the 2007 DARPA Urban Challenge. Data from a high-precision navigation system, five cameras, 12 SICK planar laser range scanners, and a Velodyne high-density laser range scanner were synchronized and logged to disk for 90 km of travel. In addition to documenting a number of large loop closures useful for developing mapping and localization algorithms, this data set also records the first robotic traffic jam and two autonomous vehicle collisions. It is our hope that this data set will be useful to the autonomous vehicle community, especially those developing robotic perception capabilities.United States. Defense Advanced Research Projects Agency (Urban Challenge, ARPA Order No. W369/00, Program Code DIRO, issued by DARPA/CMO under Contract No. HR0011-06-C-0149

Identification of a murine CD45-F4/80lo HSC-derived marrow endosteal cell associated with donor stem cell engraftment

Hematopoietic stem cells (HSCs) reside in specialized microenvironments within the marrow designated as stem cell niches, which function to support HSCs at homeostasis and promote HSC engraftment after radioablation. We previously identified marrow space remodeling after hematopoietic ablation, including osteoblast thickening, osteoblast proliferation, and megakaryocyte migration to the endosteum, which is critical for effective engraftment of donor HSCs. To further evaluate the impact of hematopoietic cells on marrow remodeling, we used a transgenic mouse model (CD45Cre/iDTR) to selectively deplete hematopoietic cells in situ. Depletion of hematopoietic cells immediately before radioablation and hematopoietic stem cell transplantation abrogated donor HSC engraftment and was associated with strikingly flattened endosteal osteoblasts with preserved osteoblast proliferation and megakaryocyte migration. Depletion of monocytes, macrophages, or megakaryocytes (the predominant hematopoietic cell populations that survive short-term after irradiation) did not lead to an alteration of osteoblast morphology, suggesting that a hematopoietic-derived cell outside these lineages regulates osteoblast morphologic adaptation after irradiation. Using 2 lineage-tracing strategies, we identified a novel CD45-F4/80lo HSC-derived cell that resides among osteoblasts along the endosteal marrow surface and, at least transiently, survives radioablation. This newly identified marrow cell may be an important regulator of HSC engraftment, possibly by influencing the shape and function of endosteal osteoblasts

IGF-1-mediated osteoblastic niche expansion enhances long-term hematopoietic stem cell engraftment after murine bone marrow transplantation

The efficiency of hematopoietic stem cell (HSC) engraftment after bone marrow (BM) transplantation depends largely on the capacity of the marrow microenvironment to accept the transplanted cells. While radioablation of BM damages osteoblastic stem cell niches, little is known about their restoration and mechanisms governing their receptivity to engraft transplanted HSCs. We previously reported rapid restoration and profound expansion of the marrow endosteal microenvironment in response to marrow radioablation. Here, we show that this reorganization represents proliferation of mature endosteal osteoblasts which seem to arise from a small subset of high-proliferative, relatively radio-resistant endosteal cells. Multiple layers of osteoblasts form along the endosteal surface within 48 hours after total-body irradiation, concomitant with a peak in marrow cytokine expression. This niche reorganization fosters homing of the transplanted hematopoietic cells to the host marrow space and engraftment of long-term (LT)-HSC. Inhibition of insulin-like growth factor (IGF)-1-receptor tyrosine kinase signaling abrogates endosteal osteoblast proliferation and donor HSC engraftment, suggesting that the cytokine IGF-1 is a crucial mediator of endosteal niche reorganization and consequently donor HSC engraftment. Further understanding of this novel mechanism of IGF-1-dependent osteoblastic niche expansion and HSC engraftment may yield clinical applications for improving engraftment efficiency after clinical HSC transplantation.The efficiency of hematopoietic stem cell (HSC) engraft-ment after bone marrow (BM) transplantation depends largely on the capacity of the marrow microenvironment to accept the transplanted cells. While radioablation of BM damages osteoblastic stem cell niches, little is known about their restoration and mechanisms governing their receptivity to engraft transplanted HSCs. We previously reported rapid restoration and profound expansion of the marrow endosteal microenvironment in response to marrow radioablation. Here, we show that this reorganization represents proliferation of mature endosteal osteoblasts which seem to arise from a small subset of high-proliferative, relatively radio-resistant endosteal cells. Multiple layers of osteoblasts form along the endosteal surface within 48 hours after total body irradiation, concomitant with a peak in marrow cytokine expression. This niche reorganization fosters homing of the transplanted hematopoietic cells to the host marrow space and engraft-ment of long-term-HSC. Inhibition of insulin-like growth factor (IGF)-1-receptor tyrosine kinase signaling abrogates endosteal osteoblast proliferation and donor HSC engraft-ment, suggesting that the cytokine IGF-1 is a crucial mediator of endosteal niche reorganization and consequently donor HSC engraftment. Further understanding of this novel mechanism of IGF-1-dependent osteoblastic niche expansion and HSC engraftment may yield clinical applications for improving engraftment efficiency after clinical HSC transplantation. © AlphaMed Press

Delayed marrow infusion in mice enhances hematopoietic and osteopoietic engraftment by facilitating transient expansion of the osteoblastic niche

Transplantation of bone marrow cells leads to engraftment of osteopoietic and hematopoietic progenitors. We sought to determine whether the recently described transient expansion of the host osteoblastic niche after marrow radioablation promotes engraftment of both osteopoietic and hematopoietic progenitor cells. Mice infused with marrow cells 24 hours after total body irradiation (TBI) demonstrated significantly greater osteopoietic and hematopoietic progenitor chimerism than did mice infused at 30 minutes or 6 hours. Irradiated mice with a lead shield over 1 hind limb showed greater hematopoietic chimerism in the irradiated limb than in the shielded limb at both the 6- and 24-hour intervals. By contrast, the osteopoietic chimerism was essentially equal in the 2 limbs at each of these intervals, although it significantly increased when cells were infused 24 hours compared with 6 hours after TBI. Similarly, the number of donor phenotypic long-term hematopoietic stem cells was equivalent in the irradiated and shielded limbs after each irradiation-to-infusion interval but was significantly increased at the 24-hour interval. Our findings indicate that a 24-hour delay in marrow cell infusion after TBI facilitates expansion of the endosteal osteoblastic niche, leading to enhanced osteopoietic and hematopoietic engraftment.Transplantation of bone marrow cells leads to engraftment of osteopoietic and hematopoietic progenitors. We sought to determine whether the recently described transient expansion of the host osteoblastic niche after marrow radioablation promotes engraftment of both osteopoietic and hematopoietic progenitor cells. Mice infused with marrow cells 24hours after total body irradiation (TBI) demonstrated significantly greater osteopoietic and hematopoietic progenitor chimerism than did mice infused at 30minutes or 6hours. Irradiated mice with a lead shield over 1 hind limb showed greater hematopoietic chimerism in the irradiated limb than in the shielded limb at both the 6- and 24-hour intervals. By contrast, the osteopoietic chimerism was essentially equal in the 2 limbs at each of these intervals, although it significantly increased when cells were infused 24hours compared with 6hours after TBI. Similarly, the number of donor phenotypic long-term hematopoietic stem cells was equivalent in the irradiated and shielded limbs after each irradiation-to-infusion interval but was significantly increased at the 24-hour interval. Our findings indicate that a 24-hour delay in marrow cell infusion after TBI facilitates expansion of the endosteal osteoblastic niche, leading to enhanced osteopoietic and hematopoietic engraftment. © 2013