KEY FACTORS FOR THE SEPARATION OF SILICON AND IRON DURING PHOSPHORUS RECOVERY FROM SLAG DISCHARGED FROM THE DOUBLE-SLAG REFINING PROCESS

In the present study, we developed a technology for concentrating and recovering phosphorus from slag-like phosphorus-containing unused resources and applied it to slag discharged during the latest steelmaking process, that is, double-slag refining process (DRP). The technology we developed consists of the following four processes: Process (1) is the initial acid elution; Process (2) involves alkali precipitation; Process (3) is the second acid elution; and, Process (4) utilizes ion-exchange. In Process (1), the addition of DPR slag to 0.5 M of a nitric acid solution for 24 min resulted in sufficient phosphorus dissolution. In Process (2), ammonia was added to the dissolved solution, and phosphorus was precipitated with high efficiency. The timing of the addition of ammonia significantly influenced the removal of silicon and iron, which would have been inconvenient to accomplish in subsequent processes. In Process (3), the precipitation obtained in Process (2) was re-dissolved in a nitric acid solution. The dissolution of phosphorus together with other elements progressed sufficiently, and we confirmed that silicon could be completely separated as silica by using high-concentration nitric acid at this stage. The fact that silicon could be removed during Process (3) was an important finding, since silicon could not have been separated in the Process (4). In Process (4), by passing the phosphorus-containing solution obtained in Process (3) through an ion exchange resin, elements other than phosphorus and silicon could be removed, which confirms that the range of applications for this technology could be expanded

Etude système de diodes lasers à verrouillage de modes pour la radio-sur-fibre en bande millimétrique

Ce travail de thèse s inscrit dans la recherche des solutions économiquementviables pour des réseaux personnels à hauts débits (plusieurs Gbps à plusieursdizaines de Gbps) opérationnels en bande millimétrique autour de 60 GHz. Aucas où ces réseaux servent un nombre élevé d utilisateurs, ils comprendront unemultitude d antennes afin d assurer l accès sans fil rapide. Afin de réduire aumaximum le coût d un module d antenne, les réseaux doivent fournir un signalanalogue à des porteuses millimetriques. Une solution prometteuse pour les systèmesde distribution qui correspond à ces besoins sont des structures à fibreoptique, laquelle permet une transmission à faibles pertes et à haute bande passante.On parle de l approche "radio-sur-fibre" (en anglais, radio-over-fiber). Laproblématique est de pouvoir générer et moduler un signal aux fréquences millimétriqueslors de la transmission optique - et ce avec des composant bas coûts.La technique utilisée dans le cadre de cette thèse est l emploi des diodes laser àverrouillage de modes. Ces derniers vont pouvoir générer des hautes fréquencestout en ne nécessitant qu une alimentation continue, et ils peuvent être modulésde manière directe ou externe. Les lasers à semi-conducteurs employés ici sontd une génération encore à l état d étude puisqu il s agit des lasers à boites (ouîlots) quantiques. Ces lasers ont montrés de très bonnes capacités à générer dessignaux électriques aux fréquences autour de 60 GHz, bien qu ayant encore, pourl instant, à une stabilité de fréquence (ou de phase) limitée. Dans le cadre des systèmesde communication opto/micro-ondes, peu de travaux approfondis ont étémenés sur ces structures.Au cours de cette thèse, plusieurs études ont été effectuées. La première portesur les propriétés générales d un système construit à partir de ce type de laser(puissances disponibles, figure de bruit, linéarité etc.). Une deuxième étude aété consacrée aux effets de la propagation des signaux dans les systèmes baséssur les lasers à verrouillage de modes, notamment de la dispersion chromatiquelaquelle a un effet considérable sur les distances de transmission. Les deux étudesmettent en avant l importance d une limitation du nombre de modes générés parla diode laser afin d optimiser non seulement le gain du lien et la puissance RFrécupérée, mais aussi la figure de bruit du système. Lors d une troisième étude, lastabilité en fréquence/phase s est révélée critique, car le bruit de fréquence/phaselimite la qualité de la transmission en introduisant un plancher d erreur mêmepour des rapports signal-a-bruit très élevés. Des différentes générations de lasersà boites (îlots) quantiques et à verrouillage de modes ont été testées. Le problèmedu bruit de fréquence et de phase persiste et ne peut pas être résolu en utilisantles techniques classiques comme les boucles à verrouillage de phase conventionnelles.Une solution pour ce problème a été développée pour les systèmes detransmission; elle permet simultanément un ajustement de fréquence supérieure(précision de quelques Hz à quelques kHz) à celle donnée par le processus de fabricationdes diodes lasers (précision de quelques GHz), ainsi qu une stabilisationde fréquence et de phase.This dissertation is related to the search for an economically sustainable solutionfor high data rate (several Gbps to several tens of Gbps) personal area networksoperating in the millimeter-wave region around 60 GHz. If such networks supplya large number of users, they need to encompass a multitude of antenna pointsin order to assure wireless access to the network. With the aim of reducing thecost of an antenna module, the networks should at best provide quasi "readyto-radiate" signals to the modules, i.e. at millimeter-wave carrier frequencies.Thanks to their low transmission loss and their high bandwidth, optical fiber distributionarchitectures represent a promising solution. The technique is referredto as the so-called "radio-over-fiber" approach whereby the analog radio signalwill be transported to the access point by an optical wave. The challenge herebyis the generation and modulation of an optical signal by a millimeter-wave radiosignal using preferably cost-efficient system components. The technique proposedherein is based on the use of mode-locked laser diodes which can generatesignals at very high frequencies under the condition of continuous current supply.Mode-locked laser diodes can be modulated both directly and externally. Thediodes employed in this work are based on so-called quantum dots (or quantumdashes); these are material structures which are themselves still subject to intensivephysical research. Signals at millimeter-wave frequencies (around 60 GHz)can easily be generated by such lasers. However, their frequency and phase stabilityis as yet limited. In the context of radio-over-fiber communication systems,these structures have not yet been studied in detail.In the course of this dissertation, several aspects are considered. A first systemstudy treats the basic properties of a system built from this type of laser source(available signal power, system noise figure, linearity etc.). A second study isdevoted to an investigation of propagation effects like dispersion, which considerablyinfluence the attainable transmission distances. An essential result of bothstudies is the importance of limiting the laser spectrum to a small number of lasermodes for an optimization of link gain, generated RF power, and system noisefigure. A third study deals with the limited frequency and phase stability whichturn out to be critical factors for transmission quality. The study of several generationsof quantum dot/dash lasers has revealed that the problems of frequencyand phase noise persist and cannot be solved using classical techniques involvinge.g. conventional phase-locked loops. In this dissertation, a solution is presentedwhich not only allows a more precise adjustment of the laser frequency (precisionin the order of Hz to kHz) than that given by the manufacturing process of thelaser (precision in the order of GHz), but also enables a stabilization of frequencyand phase.SAVOIE-SCD - Bib.électronique (730659901) / SudocGRENOBLE1/INP-Bib.électronique (384210012) / SudocGRENOBLE2/3-Bib.électronique (384219901) / SudocSudocFranceF

The effects of ERN1 on gene expression during early rhizobial infection in Lotus japonicus

Legumes develop root nodules in association with compatible rhizobia to overcome nitrogen deficiency. Rhizobia enter the host legume, mainly through infection threads, and induce nodule primordium formation in the root cortex. Multiple transcription factors have been identified to be involved in the regulation of the establishment of root nodule symbiosis, including ERF Required for Nodulation1 (ERN1). ERN1 is involved in a transcription network with CYCLOPS and NODULE INCEPTION (NIN). Mutation of ERN1 often results in misshapen root hair tips, deficient infection thread formation, and immature root nodules. ERN1 directly activates the expression of ENOD11 in Medicago truncatula to assist cell wall remodeling and Epr3 in Lotus japonicus to distinguish rhizobial exopolysaccharide signals. However, aside from these two genes, it remains unclear which genes are regulated by LjERN1 or what role LjERN1 plays during root nodule symbiosis. Thus, we conducted RNA sequencing to compare the gene expression profiles of wild-type L. japonicus and Ljern1-6 mutants. In total, 234 differentially expressed genes were identified as candidate LjERN1 target genes. These genes were found to be associated with cell wall remodeling, signal transduction, phytohormone metabolism, and transcription regulation, suggesting that LjERN1 is involved in multiple processes during the early stages of the establishment of root nodule symbiosis. Many of these candidate genes including RINRK1 showed decreased expression levels in Ljnin-2 mutants based on a search of a public database, suggesting that LjERN1 and LjNIN coordinately regulate gene expression. Our data extend the current understanding of the pleiotropic role of LjERN1 in root nodule symbiosis

Study on the Youth Project to Support from Remote Place in the Early Stage of the Disaster : Case Study of Information Support Using SNS at the Kumamoto Earthquake in 2016

In our research, we investigated information support using SNS at the time of disaster. There is an advantage that anyone can easily get and spread information. Therefore, it is effective to provide information using SNS. In conclusion, from the distant place young people of nonprofessional that they can support by using SNS. Introducing on the case of "YA4K" of facebook group who actually carried out support activities.研究ノー

スギ間伐材を用いた配向性パーティクルボードに関する研究(第 3 報) : ボードの材質に及ぼす接着剤の添加量の影響(林学部門)

スギ間伐材からストランド・パーティクルを作製し, 接着剤としてユリア樹脂(UF), メラミン・ユリア共縮合樹脂(UMF), フェノール樹脂(PF)およびイソシアネート樹脂(IC)の4種類, 含脂率を3,5,10,15%の4水準に設定して配向性およびランダムに配向させた12mm厚の単層ボードを製造した。配向性ボードの平均配向角は約10度であった。いずれのボードともに, また配向性およびランダムボードともに, 曲げ性能およびはく離強度は含脂率が増加するとともにほぼ直線的に増加した。また常態曲げ性能は, 接着剤が異なってもそれほど大きな差異はない。また, 配向性ボードの平行方向の曲げ強度は, ランダムボードのそれの約2倍, 配向性ボードの異方度は約5∿6である。いずれの接着剤の場合も, また配向性およびランダムボードともに, 厚さ膨張率は含脂率の増加とともに減少する傾向を示し, ICボードの寸法安定性が良好であった。配向性ボードの平行方向の吸湿板面寸法変化率は0.02∿0.09%の範囲にあり, 供試接着剤の種類や含脂率にはあまり影響されない。また, ランダムボードのそれは0.05∿0.11%, 配向性ボードの直交方向のそれは0.52∿1.02%であり, 含脂率の増加とともにやや寸法変化率が減少する傾向がみられた。Strand particles were oriented using a mechanical orienter, and single-layer oriented particleboards (OSB) were produced. The effect of resin content on bending properties and dimensional stability of the boards were investigated. Resins used were urea, melamine-urea, phenol and isocyanate. The bending strength in the oriented direction of the boards was about twice that of the random boards. The value of the parallel to perpendicular (∥/⊥) ratio for the bending properties reached approximately 5 to 6. The bending properties and internal bond strength were affected greatly by resin content. The thickness swelling of the boards was decreased with increasing resin content. The value of linear expansion (LE) in the oriented direction was about half of the value in the random boards. The value of LE decreased slightly with increasing resin content

コレステロール流出メカニズムの阻害は抗悪性リンパ腫治療の標的となり得る

熊本大

Molecular Species Disturbing the Fluid–Solid Phase Transition of Nitrogen Adsorbed on Graphite: Importance of Aromaticity

The fluid–solid (FS) phase transition of N 2 adsorbed on graphite is known to be depressed abnormally by conjugated coplanar molecules such as benzene and copper phthalocyanine. This paper describes an investigation of the influence of a non-aromatic conjugated species (1,3-butadiene), a non-aromatic cation acceptor (18-crown-6), a strong electron donor (tetrathiafulvalene) and a strong electron acceptor (tetracyanoquinodimethane) on the FS phase transition of N 2 , when they were preplated on graphite. These species were, in fact, found to have no significant effect. This implies that molecular properties such as cation acceptance and electron transfer are of no importance, whereas the aromaticity of co-existing species plays a crucial role in disturbing the phase behaviour of N 2