Recent Developments and Mid‐ and Long‐Term CO2 Mitigation Projects in Ironmaking

CO₂ mitigation and the stable supply of raw materials are two major issues for the steel industry. The Japanese steel industry has promoted short term developments and investments to comply with the Japan Iron and Steel Federation's voluntary action plan in parallel with developing plans for drastic CO₂ mitigation programs toward the post Kyoto protocol period. This paper describes short‐term measures in the ironmaking field such as natural gas injection technology to the sintering bed and burden distribution control with coke mixed charging. For mid and long term CO₂ mitigation, the joint project, ‘Preparatory research work for the blast furnace based innovative ironmaking technologies’ was actively promoted by the New Energy and industrial Technology Development Organization (NEDO) from FY2006 to FY2008. Based on the enhancement of carbon ‐ CO₂ reaction by close positioning of carbon and iron oxide/metallic iron, the production process and reaction mechanism in a blast furnace were studied for two innovative composites with iron oxide, metallic iron and carbon. For development at a pilot plant scale, a new project, ‘Development of innovative ironmaking process using low cost iron ore and coal’ started in FY2009. Key technologies of the project are the production process and evaluation in a blast furnace of a hybrid composite of metallic iron and carbon, so called ‘Ferro‐coke’. This paper describes key technologies and recent developments of the project.     

Burnup management simulator for small and medium sized reactors

We propose a novel burn up management simulator scheme which would maximize the discharge burn up of Small and Medium Sized Reactors (SMR) by optimum choice of Fuel Cycle Length (FCL). In this simulator, the objective being to maximize the burn up of all the subassemblies of the reactor so that burn up loss in them is a minimum and the plant availability factor is maximized. The simulator can be used both for the conventional batch refueling as well as the once through cycle schemes. Further, the designer has the option to choose a particular FCL depending upon the percentage loss in burn up.     

Design of single-site Ti embedded highly hydrophilic silica thin films with macro-mesoporous structures

Single-site Ti-containing macroporous silica thin films with mesoporous frameworks were successfully prepared on quartz substrate with high transparency by using poly(methyl methacrylate) (PMMA) microspheres and organic surfactant as template of porous structures. The presence of mesoporous structure and the differences of macroporous structure of film surface were investigated by XRD and FE-SEM measurements. The local structure of Ti moieties embedded within silica matrixes were also confirmed by UV-vis investigations. It was found that the macroporous structure and the embedded single-site Ti moieties within mesoporous frameworks were quite effective for improvement of surface hydrophilicity, i.e., the water droplet was entirely spread on the film surface even before and after irradiation of UV light.     

High butanol production by Clostridium saccharoperbutylacetonicum N1-4 in fed-batch culture with pH-Stat continuous butyric acid and glucose feeding method

A pH-stat fed-batch culture by feeding butyric acid and glucose has been studied in an acetone-butanol-ethanol (ABE) fermentation using Clostridium saccharoperbutylacetonicum N1-4. The specific butanol production rate increased from 0.10 g-butanol/g-cells/h with no feeding of butyric acid to 0.42 g-butanol/g-cells/h with 5.0 g/l butyric acid. The pH value in broth decreases with butyric acid production during acidogenesis, and then butyric acid reutilization and butanol production result in a pH increase during solventogensis. The pH-stat fed-batch culture was performed to maintain a constant pH and butyric acid concentration in the culture broth, but feeding only butyric acid could not support butyric acid utilization and butanol production. Subsequently, when a mixture of butyric acid and glucose was fed, butyric acid was utilized and butanol was produced. To investigate the effect of the feeding ratio of butyric acid to glucose (B/G ratio), several B/G ratio solutions were fed. The maximum butanol production was 16 g/l and the residual glucose concentration in broth was very low at a B/G ratio of 1.4. Moreover, yields of butanol in relation to cell mass and glucose utilization were 54% and 72% higher in pH-stat fed-batch culture with butyric acid than that of conventional batch culture, respectively.     

Effects of a humidity-stabilizing sheet on the color and K value of beef stored at cold temperatures

The effects of a humidity-stabilizing sheet containing glycerol, on the color and K value of beef stored at cold temperatures were investigated in this study. A drip-absorbing sheet seems to be effective for the preservation of meat quality, while a humidity-stabilizing sheet containing glycerol prevents the increase of metmyoglobin in cold stored beef. Maintaining samples wrapped in humidity-stabilizing sheets containing glycerol at low temperature for 7days was a functional method for conserving the concentration of inosine monophosphate. Beef samples wrapped in sheets containing glycerol had lower K values than samples wrapped in sheets not containing glycerol. When the surface of the meat starts to desiccate, the humidity-stabilizing sheet releases moisture that has been absorbed from the beef in the early stages of storage. Thus, glycerol could potentially play a role as a humidity-stabilizing controller and color preservative. This research suggests that a humidity-stabilizing sheet containing glycerol is a useful moisture controller and prevents deterioration of meat quality, discoloration, and desiccation.     

Availability of bone marrow stromal cells in three-dimensional coculture with hepatocytes and transplantation into liver-damaged mice

Rat bone marrow stromal cells (BMSCs) were cultured in porous hydroxyapatite (HA) disks for 2 weeks to form a cell layer on the surface. Freshly isolated hepatocytes were then inoculated into both BMSC-cultured and non-treated HA disks. Hepatocytes cocultured with BMSCs secreted significantly more albumin than those in monoculture in vitro. The cell-packed HA disks were implanted into the peritoneal cavity of Nagase analbuminemia rats (NARs), and 4 weeks later, blood samples were collected to measure the albumin concentration. The cotransplantation of BMSCs with hepatocytes significantly increased the serum albumin concentration in NARs. The HA disks coculturing mice hepatocytes and BMSCs were also implanted into mice, in which liver damage had been induced using carbon tetrachloride and phenobarbital. The decreased serum albumin level in liver-damaged mice was completely recovered by the transplantation of hepatocytes and BMSCs. The serum level of IL-6 in liver-damaged mice was also increased by the cotransplantation of BMSCs and hepatocytes. Thus, the transplantation of BMSCs appears to have a systemic effect on recipients through the increase in the serum cytokine level as well as a local effect on cotransplanted hepatocytes.     

Garlic as an anti-fatigue agent

More than three thousand publications in the past have confirmed the efficacy of garlic for the prevention and treatment of a variety of diseases, acknowledging and validating its traditional uses. Garlic is also used for the treatment of fatigue, although the mechanism involved remain unclear. The anti-fatigue function of garlic may be closely related to its many favorable biological and pharmacological effects. In animal studies, garlic has been shown to promote exercise endurance. Differences in the methods of processing garlic result in differences in the intensity of its anti-fatigue effect, and the most favorable form of processing has been shown to be extraction of raw garlic followed by its natural aging for a long period in a water-ethanol mixture. In human studies, it has been confirmed that garlic produces symptomatic improvement in persons with physical fatigue, systemic fatigue due to cold, or lassitude of indefinite cause, suggesting that garlic can resolve fatigue through a variety of actions. Recently, primarily in Japan, attempts have been made to measure the intensity of fatigue objectively and quantitatively using biomarkers. Currently available data strongly suggest that garlic may be a promising anti-fatigue agent, and that further studies to elucidate its application are warranted.     

Comparison between PFC and PID control systems for a pneumatic cylinder

The world population is aging, along with a decrease in population and a shortage of young workers. Mechanisms using pneumatic cylinders are therefore expected to be useful to perform tasks such as day‐to‐day work support for elderly people. However, a pneumatic cylinder involves a large time delay. Therefore, a traditional control system becomes complex, with the necessity to add Smith compensation. Therefore, we use predictive functional control (PFC). This control system is not complex even if the plant includes a time delay. This study evaluates the performance of force and position control systems using a pneumatic cylinder and PFC. We compare the PFC scheme with the proportional integral derivative (PID) control and show that PFC achieves better performance than PID control. © 2015 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

Role of boric acid for a poly (vinyl alcohol) film as a cross-linking agent: Melting behaviors of the films with boric acid

We have investigated the role of boric acid as a cross-linking agent for a poly (vinyl alcohol) (PVA) film when the film is immersed in boric acid aqueous solution. DSC results show that the films with boric acid exhibit the higher glass transition temperatures than that of the PVA film without boric acid, when the films are dried after immersing in boric acid aqueous solutions with various boric acid concentrations, implying that boric acid penetrating into the films slows down the PVA molecular motion. Furthermore, simultaneous small-angle X-ray scattering and wide-angle X-ray diffraction measurements were performed on the melting processes of the PVA films with boric acid. We found that the crystallite size increase originated from melting and recrystallization do not occur for the PVA films with boric acid, whereas in the case of the PVA without boric acid the crystallite size is enlarged in both directions parallel and perpendicular to the chain axis via melting and recrystallization on melting. These indicate that chemical reactions of boric acid to the PVA molecular chains in amorphous regions resulted in cross-linking points take place in boric acid aqueous solutions, inhibiting recrystallization on melting, because the cross-links slow down the PVA molecular motion and must not be included in the crystalline domains.     

Synthesis, thermal and mechanical properties and biodegradation of branched polyamide 4

A series of linear and branched polyamide 4 were prepared and characterized in order to study the effect of the structure on thermal and mechanical properties. Polybasic acid chlorides were effective initiators for the synthesis of the branched polyamide 4. The melting points of the polyamide 4 for the high molecular weight region were near 265 °C and showed no significant difference depending on their chain structure. On the other hand, it was found that the branched polyamide 4 showed remarkable increase of tensile strength, compared to similar molecular weight of the linear polyamide 4 (e.g. four-branched type M_w=9.28×10⁴, tensile strength=72 MPa).When the initiator having branched structure were used, gel was also formed at the initiator concentration over a certain value (e.g. 3.0 mol% for 4-branched type).The biodegradation of the branched polyamide 4 was evaluated using a standard activated sludge (e.g. four-branched type M_w=8.25×10⁴, biodegradation 41%).