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In this manuscript, we report our ground-breaking result on development of artificial multicellular structures capable for neuron like spiking activity. These structures are self-growing ensembles of vesicles whose membranes are combinations of phospholipid and viscous amphipathic molecules. The vesicles grow from a porous gel, and an osmotic pressure difference between the interior of the gel and its surrounding drives the growth. The vesicles’ membranes have also incorporated pore forming proteins. The growing ensembles exhibit spike-like dynamics in electrical potential recorded on the electrodes inserted in the ensembles. We speculate that the spike-like electrical activity is due to the breaking and leaking of the compartments, fusion, and fission of the vesicles during the growth. We demonstrate the spontaneous growth of multi-cellular lipid compartments, which can also incorporate liposomes with membrane proteins, and their generation of an electrical spike-like signal. The bottom-up development of a multicellular artificial molecular system like this report would lead the transition of material's complexity toward information transfer emulating that of a nervous system. The evidence of neuromorphic electrical activity in multicellular systems of lipid vesicles is a promising indication of feasibility of future designs of self-growing artificial proto-brains. We, therefore, think that this manuscript should attract outstanding interest from the wide community of scientists, engineers and laymen, especially those interested in in artificial life, molecular computing, origins of life, artificial cell, molecular robotics, and synthetic biology.

A theoretical study is made on the maximum injection rates of pulverized coal in ironmaking blast furnaces. The study takes account of two restrictive conditions which enable stable blast furnace operations to be maintained. One is to burn out the injected coal in the raceway zone and the other is to avoid the coal ash deposition on the blowpipe wall. The predicted maximum injection rates for some operating blast furnaces are about 190–210 kg per ton of pig-iron produced, which seem to be reasonable in comparison with experiences reported. Also, the influences of pulverized coal injection on the coke consumption, the production rate of pig-iron and the bosh gas temperature are examined in relation to some blast gas conditions such as the oxygen enrichment and the moisture addition.

石炭の産炭地は世界各地に広がっていて性状はまちまちであり，炭種のNOx濃度，燃焼効率などへの影響を精度良く把握して，環境対策をも考慮した炭種選定およびボイラの効率的運転を行うことが重要となる.そこで当研究所では，多炭種に適用できる燃焼特性予測技術の確立を目指した研究開発を推進している.その1つに小型微粉炭燃焼炉（以下，小型燃焼炉と記載）を用いての微粉炭燃焼研究があり，多くの炭種について炉内での燃焼状態を解析して，火炉出口NOx濃度の予測を可能にする手法を見出すことを1つの目的としている．これまでに燃料比（固定炭素/揮発分），N分含有率の違う12炭種の石炭について燃焼試験を行ってきた．試験では，NOx生成特性を解析するために，炉内および炉出口での燃焼ガス成分の濃度を測定している．本報告では，特に石炭性状の火炉出口NOx濃度への影響について，簡単な統計処理による定量化を試みた結果を報告する．

The conformation of alkylamino chains has been analyzed by using isolated C–D stretching vibrations. The compounds studied are N-methylpiperidine-2,6-d2, N-ethylpiperidine-1′-d1, N-propylpiperidine-1′-d1, N-butylpiperidine-1′-d1, N,N-dimethylpentylamine-1-d1, N,N′,5,5-tetramethylhexahydropyrimidine-2-d1, N,N-dimethylbutylamine-2-d1, N,N-dimethylpentylamine-2-d1 and N,N-dimethylhexylamine-2-d1. The observed C–D stretching wavenumbers for different conformations at different positions of the alkylamino chain have been correlated linearly to the C–D bond lengths calculated by ab initio molecular orbital methods. The C–D stretching wavenumbers depend significantly on the conformation in the close vicinity of the C–D bond. Isolated C–D stretching vibrational spectroscopy has great potential for being used in conformational analysis of alkylamino chains in functional and biological substances.

In the present study, a proportional relationship is derived between the specific rate of grinding, called the selection function, and the net mill power for tumbling ball mills and vibration ball mills. The proportionality constant is a function of material properties and some mill operating parameters. Also, the net mill power is expressed in terms of mill size and operating parameters. A convex trend of the net mill power in relation to the ball filling, J with a peak at about J =0.4 is obtained for tumbling mills. Vibration mills have a so called double action showing an increase in mill power with increasing J even at J ⩾0.5. These results are confirmed to be in reasonable agreement with reported experiments.

This paper reviews the theoretical work on dust explosions developed by the authors. The bases of the work are a simplified model of the dust cloud suspension, the flame propagation process and the combustion of solid particles. As a result, characteristics of the phenomena are expressed by combining reaction kinetics, heat transfer theory and thermodynamics. Further, theoretical information on some protection methods is derived and shown to be safe. It thus appears that, although this treatment includes some severe assumptions, it could provide a basis for more rigorous theories for prediction of dust explosion and design of protection systems.

The present study deals with an analysis of the selection function for mills using balls as grinding media. The grinding mechanism assumes that a particle caught by two colliding balls will be ground only if the ball impact generates or activates at least one single crack within the particle causing the fragmentation. The derived selection function becomes convex in relation to particle size on a log—log chart, which has been observed experimentally. Further, the effects of ball properties and powder and ball fillings on the selection function or the mill capacity are examined theoretically and agree reasonably well with experiment.

This research aims to support chest computed tomography (CT) medical checkups to decrease the death rate by lung cancer. We have developed a remote cooperative reading system for lung cancer screening over the Internet, a secure transmission function, and a cooperative reading environment. It is called the Network-based Reading System. A telemedicine system involves many issues, such as network costs and data security if we use it over the Internet, which is an open network. In Japan, broadband access is widespread and its cost is the lowest in the world. We developed our system considering human machine interface and security. It consists of data entry terminals, a database server, a computer aided diagnosis (CAD) system, and some reading terminals. It uses a secure Digital Imaging and Communication in Medicine (DICOM) encrypting method and Public Key Infrastructure (PKI) based secure DICOM image data distribution. We carried out an experimental trial over the Japan Gigabit Network (JGN), which is the testbed for the Japanese next-generation network, and conducted verification experiments of secure screening image distribution, some kinds of data addition, and remote cooperative reading. We found that network bandwidth of about 1.5 Mbps enabled distribution of screening images and cooperative reading and that the encryption and image distribution methods we proposed were applicable to the encryption and distribution of general DICOM images via the Internet.

Relief venting is one of the protective methods most commonly provided against dust explosion hazards. Safety design has so far been based upon the empirical vent ratio, S/V, the area of vent per unit volume of vessel. However, direct use of this term as a scale-up factor is not theoretically sound. A revised form of scale-up factor as to relief venting is proposed on the basis of the unsteady-state macroscopic energy balance and several assumptions. The derived results show that the relationship between vent area and vessel volume can be characterized by a dimensionless term which must be used instead of the conventional vent ratio. Calculated results based upon the theory agree fairly well with past experimental data.

粉粒体移動層内に形成される死領域にはその縮流に応じて側部に形成される場合と中央に形成される場合とがある.本報では2次元重力場で形成される死領域輪郭に対して理論的および実験的に検討した.理論的には塑性力学でのすべり線が死領域と流動域との境界を与えるとする考えを基に, 二つの死預域の場合についてそれぞれ縮流の方向より主働あるいは受働の応力状態を仮定し, 死領域境界の軌跡を解析した.また実験的には測定が困難な移動層粉体層の内部摩擦係数と壁摩擦係数について検討を行い, 理論との比較を可能にした.理論と実験結果とはおおむね良好な一致を見せており二つの場合における死領域輪郭を一つの理論で予測できることが示された.

Based upon a simplified grinding mechanism, an analysis of the selection function is made for vibration mills. The mechanism considered is that a particle nipped by two colliding balls is to be ground only if the ball impact generates or activates at least one crack within the particle and the crack is big enough for fragmentation. The derived selection function increases with increasing size up to a certain value and then decreases with increasing particle size. This trend has been observed elsewhere by experiment. Also, the present paper examines the effects of the ball on the selection function.

The present study deals with one theoretical attempt which optimizes the conditions of pulverized coal injection in ironmaking blast furnaces. Firstly, pulverized coal combustion in the raceway zone is analyzed based on a simplified raceway zone model. Then the derived result is used together with the blowpipe zone combustion theory in order to estimate the optimum coal injection and blasting conditions. In this optimization, two factors are proposed. One is the burnout factor indicating the possibility of complete burnout of injected coal within the raceway zone. The other is called the ash deposition factor showing the possibility of fused coal ash deposition on the blowpipe or tuyere wall. These two values less than unity predict a good operation of coal injection to be achieved. Some practical data of coal injection in Japanese blast furnaces are used to examine the derived theory. Also some sensitivity tests of the theory are undertaken in order to clarify the effects of some operational parameters on the burnout and ash deposition factors.

Pulverized coal is being used increasingly as a blast furnace injectant. It is injected into a blowpipe zone where spontaneous ignition and combustion occur by mixing with the hot blast.A theoretical study is made on the ignition and combustion of injected coal particles in the blowpipe zone. The theory uses a simple combustion model in which diffusion of gaseous oxygen is dominant for the combustion rate. The derived results show the effects of coal properties and blast and injection conditions on the degree of burn out and the blast gas temperature at the tuyere nose. These results are compared qualitatively with reported experiments and reasonable agreement is obtained.In spite of some severe assumptions used in the theory for simplicity, the present objective is satisfied, which is to provide preliminary information for optimization of the injection conditions.

On the basis of the uniform dispersion model of mono-sized particles, the present paper deals with the upper limit of explosible dust concentration in terms of oxygen concentration. This limit is defined as the maximum dust concentration resulting in the propagation of a flame which consumes a definite amount of oxygen allocated to one solid particle. Comparisons with the existing data are reasonable. An evaluation of this upper limit will be particularly useful in view of the scarcity of data arising from the difficulties inherent in experimental techniques.