Research on the Activity of Components in Fundamental System in Iron Blast Furnace Slag. III : Measurement of the Activity of Silica and Alumina in CaO-MgO-SiO_2-Al_2O_3 System

Our previous reports described the determination of activity of SiO_2 and Al_2O_3 in the slag of CaO-SiO_2-Al_2O_3 system by using the e. m. f. method of double cell. The present study investigated the effect of MgO on the activity of SiO_2 and Al_2O_3. From the experimental results it was found that at a constant concentration of Al_2O_3, activity coefficient of SiO_2, γ SiO_2 increased as substitution of MgO for CaO increased. With the addition of MgO, the activity of silica approached Raoult\u27s law. At a constant MgO concentration, the amphoteric nature of Al_2O_3 was clarified as in CaO-SiO_2Al_2O_3 system. Concerning the effect of MgO on the activity of Al_2O_3, an intimate relation exists between αAl_2O_5 and basicity, that is, by chosing the basicity as N_/N_, a relationship could be found between log αAl_2O_3 and basicity which corresponded to the results obtained in the slag of CaO-SiO_2-Al_2O_3 System. The above facts show the behaviour of MgO which acts as a base

Study on the Reduction Process of Iron Oxide Pellets in Isothermal Fixed Bed

A mathematical model for the isothermal fixed bed and one of the numerical calculating method for this model are presented in this paper. The reaction rate accepted in this model is determined on the basis of the rate observed for single iron oxide pellet. In order to clarify the availability of the mathematical model for analyzing the metallurgical reactors, change in the average fractional reduction over the whole bed with the progress of time was observed during the reduction of iron oxide pellets with CO and H_2 by the use of the experimental fixed bed. The observed data are in good agreement with the calculated curves except in the case where the pellets cracked badly during the reduction. It is, therefore, found that the distributions of process variables in isothermal fixed bed can be estimated with the considerable accuracy by the model mentioned above, and that the reaction rates of pellets with CO and H_2 used in this paper are expected to be available for the process analysis of metallurgical reactors

Research on the Activity of Components in Fundamental System of Iron Blast Furnace Slag. II : Measurement of the Activity of Alumina in the System CaO-SiO_2-Al_2O_3

The e. m. f. of the following cell Fe-Al-C_ | CaO-SiO_2-Al_2O_3 (I) | C or MgO | CaO-SiO_2-Al_2O_3 (II) | Fe-Al-C_. was measured at 1630℃ with the reference slags CaO 45.2, SiO_2 2.2 and Al_2O_3 53.7 wt % respectively. It was found that the e. m. f. sharply increased with increasing concentration of lime, and then decreased gradually. On the other hand, with constant alumina series, a marked increase of the e. m. f. was observed in the range near the liquidus of 2CaO-SiO_2. Now choosing the standard state as the solid alumina at 1630℃, the activity of alumina. in a given slag was calculated from the e. m. f. by the following equation : E=RT/6Flna_ From the authors\u27 data, the isoactivity lines were drawn on the ternary coordinates of CaO-SiO_2-Al_2O_3. And symmetrical isoactivity lines were obtained about the straight line connecting between 2CaO-SiO_2 at CaO-SiO_2 system and Al_2O_3 coordinate, which may be explained by the change of existing anion species of aluminum in the slag. Finally the most probable anion species and their stabilities were discussed

On the Deoxidation of Liquid Iron with Bubbles of Argon-Calcium Gas Mixture

To clarify the applicability of gaseous metal for the purification of liquid iron and steel, a study was made on the deoxidation with Ar-Ca gas bubbles floating up in iron melt. The present study will also give some informations on the behavior of complex deoxidizer containing calcium. The results obtained are as follows : (1) At 1550℃, the interaction parameters were e_0^=-535 and e_^=-1330, and the equilibrium constant for the reaction of [Cal + [O] =CaO was log K_=log a_a_0=-9.82. (2) The decrease in [O] was directly proportional to the amount of calcium added in the range of high oxygen content ([O]>150ppm) and was expressed by an exponential function of it in the range of low oxygen content ([O]<100ppm). This phenomenon is interpreted as follows ; the deoxidation process is controlled by the supply of calcium from the bubble side to the reaction zone in the former and by the supply of oxygen from the bulk of melt to that zone in the latter case. (3) The increase in the floating distance of Ar-Ca bubbles in the metal bath raised the efficiency of calcium utilization

Reduction Rate of Iron Oxide Pellets with Hydrogen

For analyzing the reduction process in the metallurgical reactor, especially in blast furnace, the reduction rates of hematite pellet and iron oxide pellet pre-reduced to wustite, "wustite pellet", were expressed by a mathematical model and the rate parameters thereof were determined. An unreacted core model was applied to simulate the hydrogen reduction of iron oxide pellets within the temperature range from 850 to 1, 150℃. Comparison of the rate constant of chemical reaction and its activation energy of hematite pellet with those of wustite pellet did not show significant difference. The pellets used had an activation energy of about 21 to 26 kcal/mol. In the macro- and microscopic observation of iron oxide pellets during the reduction, the reaction proceeded topochemically. A sharp interface was found between wustite and iron phase in the case of hematite pellet, whereas reaction zone of about 300μ was found in the case of wustite pellet. The calculated reduction curves almost agreed with the observed values with the changes of temperatures, diameters of the pellet and concentrations of reducing gas. These calculated curves further agreed with the values observed by altering one of the experimental conditions during reduction

Oncolytic virotherapy promotes radiosensitivity in soft tissue sarcoma by suppressing anti-apoptotic MCL1 expression

Soft tissue sarcoma (STS) is a rare cancer that develops from soft tissues in any part of the body. Despite major advances in the treatment of STS, patients are often refractory to conventional radiotherapy, leading to poor prognosis. Enhancement of sensitivity to radiotherapy would therefore improve the clinical outcome of STS patients. We previously revealed that the tumor-specific, replication-competent oncolytic adenovirus OBP-301 kills human sarcoma cells. In this study, we investigated the radiosensitizing effect of OBP-301 in human STS cells. The in vitro antitumor effect of OBP-301 and ionizing radiation in monotherapy or combination therapy was assessed using highly radiosensitive (RD-ES and SK-ES-1) and moderately radiosensitive (HT1080 and NMS-2) STS cell lines. The expression of markers for apoptosis and DNA damage were evaluated in STS cells after treatment. The therapeutic potential of combination therapy was further analyzed using SK-ES-1 and HT1080 cells in subcutaneous xenograft tumor models. The combination of OBP-301 and ionizing radiation showed a synergistic antitumor effect in all human STS cell lines tested, including those that show different radiosensitivity. OBP-301 was found to enhance irradiation-induced apoptosis and DNA damage via suppression of anti-apoptotic myeloid cell leukemia 1 (MCL1), which was expressed at higher levels in moderately radiosensitive cell lines. The combination of OBP-301 and ionizing radiation showed a more profound antitumor effect compared to monotherapy in SK-ES-1 (highly radiosensitive) and HT1080 (moderately radiosensitive) subcutaneous xenograft tumors. OBP-301 is a promising antitumor reagent to improve the therapeutic potential of radiotherapy by increasing radiation-induced apoptosis in STS

チ ノ ネットワーク セイチョウ モデル

知の創造プロセスに関する先行研究では、これまでいくつかのモデルが提唱されてきた。本稿で我々は、知の創造プロセスについて「増殖段階」「混在段階」「創造段階」の3段階からなる【知のネットワーク成長モデル】を新たに提唱する。本モデルが従来のモデルと異なる点は、知の創造理論について、数学の一分野であるノード(点)とエッジ(線)で結ばれた「グラフ」を用いたグラフ理論や、ライフサイエンスの分野である「タンパク質相互作用ネットワーク(PPI: Protein-Protein Interaction)」などを援用して、知の創造プロセスを提唱している点にある。さらに「混在段階」と「創造段階」の溝(キャズム)を越え、混在させた知に新しい価値を付加するためのセレンディピティの必要性についても言及している点にある。In this paper we describe a novel knowledge creation model, the "three-step knowledge network model," which comprises the propagation step, the mixing step, and the creation step. This model uses knowledge networks first proposed by Willard Van Orman Quine\u27s, and graph theory to describe the knowledge creation process. We use higher education as a example of knowledge creation that this model can describe, and in the future hope to apply this model to other phenomena

Research and Design of a Routing Protocol in Large-Scale Wireless Sensor Networks

无线传感器网络，作为全球未来十大技术之一，集成了传感器技术、嵌入式计算技术、分布式信息处理和自组织网技术，可实时感知、采集、处理、传输网络分布区域内的各种信息数据，在军事国防、生物医疗、环境监测、抢险救灾、防恐反恐、危险区域远程控制等领域具有十分广阔的应用前景。 本文研究分析了无线传感器网络的已有路由协议，并针对大规模的无线传感器网络设计了一种树状路由协议，它根据节点地址信息来形成路由，从而简化了复杂繁冗的路由表查找和维护，节省了不必要的开销，提高了路由效率，实现了快速有效的数据传输。 为支持此路由协议本文提出了一种自适应动态地址分配算——ADAR（AdaptiveDynamicAddre...As one of the ten high technologies in the future, wireless sensor network, which is the integration of micro-sensors, embedded computing, modern network and Ad Hoc technologies, can apperceive, collect, process and transmit various information data within the region. It can be used in military defense, biomedical, environmental monitoring, disaster relief, counter-terrorism, remote control of haz...学位：工学硕士院系专业：信息科学与技术学院通信工程系_通信与信息系统学号：2332007115216