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アルゴン希釈下でのモノシランの熱分解を様々な形状のガス送入口を有する, 内径43および50mmのバッチ流動層を用いて行った.モノシランの反応率は大概99%以上で, フリーボードでの反応は無視できた.平均粒子径が0.316mm以上の場合については, ノズル型のガス送入口を用いれば, 粒子の凝集 (クロッギング) は生じにくいが, 923K以上ではモノシランのジェットの周りに粒子凝集物が形成された.他の3タイプの平板型分散板では, 凝集物は比較的低温で層断面の全体にわたり形成された.微粉の生成はノズル型の場合に比較的顕著であった.粒子径が小さい場合には凝集物が形成されやすい.凝集物の生成を防ぐには, 粒子の循環速度を上げ, 局所的な単位体積当りの析出速度を減少させる必要がある.微粉の生成を減少させるには析出速度に対する微粉生成速度の比を減少させる必要があり, これらのことから, 流動層グリッドゾーンのデザインが重要である.粒子の線成長速度は, 粒子径によらず一定であることが示唆された.反応率および微粉の流出量の実測値を, 前報で報告した速度式から予測される結果と比較し, 大概一致することを示した.

A simulation model for behavior of gas and solid in fluidized bed grid zone was developed and its validity was tested by comparison of its numerical results with the experimental cold model data of particle velocity and temperature relaxation in jet to guarantee the validity of the model. The proposed model was applied to chemical vapor deposition of polycrystalline silicon by monosilane pyrolysis, taking into account of both homogeneous decomposition to fine powder and heterogeneous chemical vapor deposition on the surface of silicon particles. A computational approach considering the local rate of thermal decomposition of monosilane in a grid zone was carried out to simulate the level of monosilane conversion. The numerical results on fines formation in the jet were much smaller than the previously reported experimental results on the fine elutriation from fluidized beds. The fines formation was confirmed to occur mainly in bubbles. To discuss clogging phenomena quantitatively, the relative rates of deposition and fine formation were defined as the ratios of the total deposition rate and fines formation rate to the circulation rate of solid in the annulus. The numerical well explained the experimentally observed effects of gas velocity, temperature, silane concentration and grid structure on the possibility of clogging.

希釈ガスとしてアルゴン, ヘリウム, 水素を用い, 内径50mmの回分式流動層を用いてモノシランの熱分解を行った.グリッド部における粒子凝集物の生成を防ぐため, 多孔質分散板を用い, 電気炉の下方に設置した.層内の最高温度を代表温度とした.クロッギングが生成する温度は, 水素, アルゴン, ヘリウム希釈の順に低下した.モノシラン反応率をアレニウス型のプロットにより解析したところ, 全ての希釈ガスについて, 見かけの活性化エネルギーは異相反応速度の真の活性化エネルギーとほぼ一致した.水素中と, アルゴンまたはヘリウム中での反応率の違いを定量的に説明した.微粉生成率の違いも気相反応速度に対する水素の阻害により説明された.アルゴン中および水素中での生成物の析出物形状, 結晶の成長, 粒子径あるいは結晶子径の違いを, X線回折, 透過型および走査型電顕により測定した.水素中での析出シリコン表面は, 明らかになめらかで, 特徴的結晶成長がみられた。水素中で生成した微粉の一次粒子径はアルゴン中のそれに比し明らかに大きかった.

Natural mordenite (NM), natural clinoptilolite (NC), HDTMA-modified natural mordenite (SMNM) and HDTMA-modified natural clinoptilolite (SMNC) have been proposed for the removal of As(V) from aqueous solution (HDTMA = hexadecyltrimethylammonium bromide). Influence of time on arsenic sorption efficiency of different sorbents reveals that NM, NC, SMNM and SMNC require about 20, 10, 110 and 20 h, respectively to reach at state of equilibrium. Pseudo-first-order model was applied to evaluate the As(V) sorption kinetics on SMNM and SMNC within the reaction time of 0.5 h. The pseudo-first-order rate constants, k are 1.06 and 0.52 h −1 for 1 and 0.5 g of SMNM, respectively. The observed k values 1.28 and 0.70 h −1 for 1 and 0.5 g of SMNC, respectively are slightly high compared to SMNM. Surfactant surface coverage plays an important role and a significant increase in arsenate sorption capacity could be achieved as the HDTMA loading level on zeolite exceeds monolayer coverage. At a surfactant partial bilayer coverage, As(V) sorption capacity of 97.33 and 45.33 mmol kg −1 derived from Langmuir isotherm for SMNM and SMNC, respectively are significantly high compared to 17.33 and 9.33 mmol kg −1 corresponding to NM and NC. The As(V) uptake was also quantitatively evaluated using the Freundlich and Dubinin–Kaganer–Radushkevich (DKR) isotherm models. Both SMNM and SMNC removed arsenic effectively over the initial pH range 6–10. Desorption performance of SMNM and SMNC were 66.41% and 70.04%, respectively on 0.1 M NaOH regeneration solution.

This paper studies several designs of network-based FPGA implementation of a stochastic simulation algorithm called the next reaction method, known for its large number of calculation involved. The procedure is divided into several subdivisions which will be implemented as independent modules, and they are connected with configurable interconnection networks so as to provide high throughput. By performing a multi-threading simulation, 3.6 times speedup was obtained compared with an execution on general purpose processors.

The sorption performance of a modified carbon black was explored with respect to arsenic removal following batch equilibrium technique. Modification was accomplished by refluxing the commercial carbon black with an acid mixture comprising HNO(3) and H(2)SO(4). Modification resulted in the substantial changes to the inherent properties like surface chemistry and morphology of the commercial carbon black to explore its potential as sorbent. The suspension pH as well as the point of zero charge (pH(pzc)) of the material was found to be highly acidic. The material showed excellent sorption performance for the removal of arsenic from a synthetic aqueous solution. It removed approximately 93% arsenic from a 50mg/L solution at equilibration time. The modified carbon black is capable of removing arsenic in a relatively broad pH range of 3-6, invariably in the acidic region. Both pseudo-first-order and second-order kinetics were applied to search for the best fitted kinetic model to the sorption results. The sorption process is best described by the pseudo-second-order kinetic. It has also been found that intra-particle diffusion is the rate-controlling step for the initial phases of the reaction. Modelling of the equilibrium data with Freundlich and Langmuir isotherms revealed that the correlation coefficient is more satisfactory with the Langmuir model although Freundlich model predicted a good sorption process. The sorption performance has been found to be strongly dependent on the solution pH with a maximum display at pH of 5.0. The temperature has a positive effect on sorption increasing the extent of removal with temperature up to the optimum temperature. The sorption process has been found to be spontaneous and endothermic in nature, and proceeds with the increase in randomness at the solid-solution interface. The spent sorbent was desorbed with various acidic and basic extracting solutions with KOH demonstrating the best result ( approximately 85% desorption).

DNA−Pt complexes have shown novel enzymatic activity as a peroxidase similar to that of horseradish peroxidase in the colorimetric reaction with its substrate. The enzymatic activity of these complexes increased with increasing reaction time and pH in reaction solutions of DNA and K2[PtCl4]. This enhanced enzymatic activity was attributed to the increase in Pt conjugated to DNA in the complex. The enzymatic activity per unit mole of the DNA−Pt complex was significantly higher for complexes prepared with high molecular weight DNA because the enzymatic activity of the complex per repeat unit of DNA was almost constant for these complexes prepared under the same reaction conditions. All the DNA−Pt complexes in this study prepared with different DNA sequences (i.e., [A]20, [G]20, [C]20, [T]20, and [AG]10) exhibited peroxidase enzymatic activity. These complexes showed good thermal stability as compared to native horseradish peroxidase.

The dynamics and surface chemistry of tert-butanethiol (TBT) adsorptive removal over silver-exchanged Y zeolite (Ag-Y) were studied under ambient conditions. Saturation uptake on Ag-Y was higher than that on H-Y and Na-Y. The structural analyses by a combination of X-ray diffraction, Ag K-edge X-ray absorption near-edge structure (XANES)/extended X-ray absorption fine structures (EXAFS), Ag L(III)-edge XANES, S K-edge XANES, and in situ UV-vis show that the AgSH molecule, Ag(2)S monomer, and Ag(4)S(2) cluster are the dominant silver species in TBT-saturated Ag-Y. Dynamic changes in adsorbed intermediates, gas-phase products, and the silver sulfides were followed by in situ FTIR, mass spectroscopy and in situ UV-vis, respectively. The results show the following reaction mechanism: (1) formation of iso-butene and adsorbed H(2)S on the Ag(+) site via C-S cleavage of hydrogen-bonded TBT initially adsorbed on the Ag(+) site; (2) conversion of the adsorbed H(2)S to AgSH and H(+) on zeolite; (3) the reaction of two Ag-SH species to yield Ag(2)S and H(+) on zeolite.

Stochastic simulation of biochemical systems has become one of major approaches to study life processes as system, yet is a computational challenge to run the simulation due to its vast calculation cost. This paper shows the implementation and evaluation of a stochastic simulation algorithm (SSA) called ?First Reaction Method? on an FPGA-based biochemical simulator. It achieves high throughput by (1) consecutively throwing data into deeply-pipelined floating point arithmetic units, and (2) by distruibuting multiple simulators for parallel execution. As the result of evaluation on an FPGA-based simulation platform called ReC-SiP2, the simulator outperforms execution on Xeon 2.80 GHz by approximately 80 times, even with large-scale bio-chemical systems.

The behavior of B, Cr, Se, As, Pb, Cd, and Mo in the leachates generated from two combustion residues, coal-fired power plant fly ash and municipal solid waste incineration ash, during precipitation of ettringite is presented. Experiments also were performed using modeled waste leachates as well as controlled solutions containing all the investigated elements. Moreover, to determine the possible effect of pH, lime treatment was conducted using the waste and modeled leachates. Results indicated the removal of B, Se, and Cr from the leachates because of incorporation of their oxyanions in the ettringite structure. The removal of B could further be explained by considering the structure of ettringite and monosulfoaluminate. The removal of Pb also occurred, probably because of lime-induced precipitation of Pb(OH)2. Similarly, the removal of As was observed as a result of lime-induced precipitation of Ca3(AsO4)2 and incorporation into the ettringite structure. On the other hand, the precipitation of ettringite did not reduce the concentrations of Mo and Cd because of the complex nature of these elements in the leachates. The results also suggest that the presence of high amounts of constituents such as Cl−, an alkali metal in the solution, also affected ettringite precipitation behavior. Moreover, elemental speciations as well as the presence of other constituents in the solution affected the incorporation by ettringite.

This communication reports the laboratory scale study on the production of cement clinkers from two types of municipal solid waste incineration fly ash (MSW ash) samples. XRD technique was used to monitor the phase formation during the burning of the raw mixes. The amount of trace elements volatilized during clinkerization and hydration, as well as leaching behaviours of the clinkers obtained from optimum compositions, were also evaluated. From the results it is observed that all of the major components of ordinary Portland cement (OPC) clinkers are present in the produced clinkers. Results also show the volatilization of considerable amounts of Na, K, Pb, Zn and Cd during the production of clinkers. However, major parts of the toxic elements remaining in the clinkers appear to be immobilized in the clinkers phases. Hydration studies of the clinkers obtained from optimum compositions show that the clinkers prepared from raw MSW ash are more reactive than the washed MSW ash based clinkers. TG/DTA analyses of the hydrated pastes show the formation of hydration products, which are generally found in OPC and OPC derived cements. The initial study, therefore, shows that more than 44% of MSW ash with the addition of very small amounts of silica and iron oxide can be used to produce cement clinkers. The amount of CaCO3 necessary to produce clinkers (approximately 50%) is also smaller than the same required for the conventional process (more than 70%).

The separation of La, Pr and Nd (Ln) using a supported liquid membrane system was studied. A water-soluble chelating agent, diethylenetriaminepentaacetic acid (DTPA), was added to the feed or stripping phase to improve permeation rates and selectivities. In the presence of DTPA in the feed phase, La was recovered selectively and the selectivity of Pr with respect to Nd attained was 2.5. However, when DTPA was added to the stripping phase, Ln could permeate even in the pH range in the stripping phase where permeation was hardly detected without DTPA. These phenomena were explained by the difference in the stabilities of chelate formation of Ln ions with DTPA.

Standard soil samples contaminated with various standard cyanocompounds were prepared. Column elution experiments and analyses were conducted. Compounds with an easy capacity for dissociation to ions, such as KCN and potassium hexacyanoferrate(III), were found to be eluted by forming free cyanide even in fresh water. Hexacyanoferrate(II) salts, such as potassium hexacyanoferrate(II) and iron(III) hexacyanoferrate(II), were found not to be dissociated in water, but were dissociated and diffused under alkaline conditions (pH >13). Hexacyanoferrate(II) ion was found to be more easily dissociated in water with a higher pH. Column tests as above were also conducted for soil samples taken from a former paint ink factory using iron(III) hexacyanoferrate(II), cyanogen chloride, potassium cyanate, copper cyanide, as well as potassium cyanide, as raw materials. It was demonstrate that iron(III) hexacyanoferrate(II) was dissociated and eluted under alkaline conditions. The elution rate was reduced when the contaminated soil was sandwiched with standard soil layers. Further, it was found that the Fe(CN) 6 4− ion eluted with NaOH from hexacyanoferrate acid in soil, were easily decomposed into cyanic acid or other byproducts by UV with the addition of ozone and H 2 O 2 .

The effects of addition of diethylenetriaminepentaacetic acid (DTPA) to the stripping phase on the permeation rates of rare earth metal ions (Ln 3+ ) through a supported liquid membrane (SLM) were investigated. It was note worthy that in the presence of DTPA Ln 3+ permeated through the SLM even in the range of high pH in the stripping phase where permeation of these ions was not detectable without DTPA. By measurement of the concentrations of Ln in the SLM, the formation of DTPA-Ln chelates led to an improvement in the permeation rates at high pH in the stripping phase.

Selective methanation of CO was performed over Ni/TiO 2 . CO in reformate gas was completely removed at 150-300 °C. The CH 4 concentration in the outlet gas could be maintained below 1% in the entire temperature region because Ni/TiO 2 suppressed the CO 2 methanation reaction. It can be considered that the formation of CO by the reverse water-gas-shift reaction is blocked by the application of TiO 2 to the support of Ni catalyst and that it results in the high CO/C02 selectivity of Ni/ Ti0 2 .

The 20th International Symposium on Chemical Reaction Engineering (ISCRE 20) was held on Sunday 7–Wednesday 10 September 2008. The scientific theme for ISCRE 20, Green Chemical Reaction Engineering for a Sustainable Future—Beyond the Kyoto Protocol, was chosen for a reason that the global environment issues are of great interest of the world and we, chemical reaction engineers, are requested and able to tackle the issues. The venue was Kyoto International Conference Center where the Kyoto Protocol was agreed at the 3rd Session of the Conference of the Parties to the United Nations Framework Convention on Climate Change (COP 3) in 1997. The year of 2008 was the first year of the commitment period to reduce the overall emissions of greenhouse gases by at least 5 per cent below 1990 levels.ISCRE 20 was hosted by the Society of Chemical Engineers, Japan (SCEJ) and operated by the SCEJ Divisions of Chemical Reaction Engineering, Energy Engineering, and Environmental Engineering and the Asia–Pacific Chemical Reaction Engineering (APCRE) Working Party. The Japanese Organizing Committee was consisted of 29 chemical reaction engineers of Steering Committee and 17 established scientists and engineers of Advisory Board. The Organizing Committee is grateful to the International Scientific Committee members, 19 members solicited from Asia–Pacific region, 15 members from Europe, and 10 members from the USA, for their great contribution in nominating plenary speakers as well as reviewing the abstracts submitted to the symposium. The Organizing Committee acknowledges Dr. Jan Lerou and Prof. Dan Luss for their kind instruction given to manage the symposium.Responding to the Call for Papers 374 abstracts were submitted for the presentation from 38 countries and regions worldwide as shown in Figure 1. The submitted abstracts were reviewed by the Scientific Committee and the Organizing Committee members, resulting in the acceptance of 311 papers. Finally 283 papers (76% net acceptance) were presented as 194 oral and 89 poster papers at the meeting. The Organizing Committee took a policy to accept as many oral papers as possible, based on the preference of the contributors. The distribution of oral and poster presentations by topic is shown in Table 1. (See more in PDF)

Publisher Summary This chapter discusses the effect of added-Ca/S molar ratio, furnace temperature, and heating rate during combustion on the behavior of sulfurous acid gas emission from a briquette of high-sulfur coal with limestone. The suitable temperature for efficient sulfur capture is 973–1073 Kelvin while sulfur retention is not improved by the further addition of limestone beyond Ca/S of 2. Rapid heating led relatively high degrees of sulfur retention, because sulfurous acid gas evolved during the combustion of volatile matter could also be captured by calcined limestone. Briquetting of high-sulfur coal with limestone depressed sulfurous acid gas emission during combustion; For instance, the degree of sulfur retention attained to 78% at 1073 K and added-Ca/S of 2.8. The combustion temperature suitable for desulfurization is between 973 and 1073 K. Plenty of sulfurous acid gas is evolved during the combustion of volatile matter. When the briquette is burnt in rapid heating rate, added limestone simultaneously decomposed and captured sulfurous acid gas efficiently.

As a countermeasure against global warming, large scale afforestation of arid land which is hardly used for crop cultivation has been receiving attention. By large scale afforestation, atmospheric CO2 will be fixed into plants. In arid land, however, most of the rainwater is lost by runoff and evaporation. Effective use of rainwater is required for afforestation. Thus, we made an original runoff model to evaluate water distribution in our research area in Western Australia. In this study, first of all, we tested the effect of the treatment way of the water movement around the watershed, and secondly, the effect of rainfall input method on the numerical estimation results of water level change.

Recently, the photocatalytic activity of titania has attracted considerable attention for solving various environmental problems. Photocatalysis is considered to be effective in air purification, water purification, and used for dealing with various types of environmental pollution. The smaller the particle size of titania, the faster the photocatalysis proceeds. Since our previous study revealed that the modification of synthesis process reduced the particle size of silica, we attempted to apply this process to synthesise titania, with an objective of obtaining titania with high photocatalytic activity. This paper describes an unconventional gas-phase synthetic method involving high-temperature hydrolysis.

Biomass has been focused as a fuel resource because of its huge abundance and carbon-neutral characteristics. Thus, we attempted to use tree biomass as the resource to automotive fuel. From the global warming point of view, the biomass energy production from large-scale plantation is required, however, the land use should not be changed from crop field or forest land. In the present paper, the feasibility of the use in Japan of biofuel from woody biomass produced in large arid area of Western Australia, where the present authors demonstrated that the large-scale afforestation is possible even in an arid land when introducing water management and plantation technologies, has been evaluated using LCA method, by considering the actual condition of our afforestation area. Furthermore, some sensitivity analysis is conducted on the effects of composition ratio of electric power sources.

The typing of the D1S8 (MS32) locus using the minisatellite variant repeat (MVR) polymerase chain reaction (PCR) method was performed by visualising amplified DNA stained with ethidium bromide. The results from rapid detection MVR-PCR were compared with those from the original MVR-PCR using Southern blot hybridisation with a 32P-labelled probe. With genomic DNA extracted from blood samples of 40 healthy unrelated Japanese individuals, the first 41 codes, on average, were correctly determined by rapid detection MVR-PCR without band intensity information, compared with at least 60 codes typed by the original MVR-PCR. The rapid detection MVR-PCR method was applied to bloodstains to simulate forensic samples. On average, 39 code positions could be determined from DNA extracted from 3-month-old bloodstains of six persons. Rapid detection MVR-PCR is more convenient than the original MVR-PCR, furnishes much information with regard to personal identification, and should be applicable to forensic fields.

It is a great pleasure to publish here a special issue of the Journal of Chemical Engineering of Japan titled, “Sustainable Chemical Engineering.” This special issue has been planned by the voluntary members of the Division of Environment, Society of Chemical Engineers, Japan (SCEJ), and edited by the members as guest editors of the issue. The main purpose of publishing this special issue is to provide opportunities of publishing research and technical topics related to environmental chemical engineering for a wide range of authors and readers interested in this field. This issue includes 21 high-quality articles: 1 review paper and 20 research papers, selected out of 31 submissions through a strict reviewing process by distinguished reviewers. The issue finally covers a wide range of environmental topics from micro-scale to global environment. We believe this special issue is beneficial all the readers of the journal, and stimulate the research activities of the environmental chemical engineering in the future.

The deoxyribonucleic acid (DNA) typing of human leukocyte antigen (HLA)-DQA1 from single hairs is described. HLA-DQA1 genotypes could be determined from single plucked hair roots. However, it was not easy to type HLA-DQA1 with hair shaft portions. Increase in the specimens of hair shaft portions (over 10 cm in length) to get sufficient DNA caused inhibition of polymerase chain reaction (PCR). Synthetic melanin as well as the one extracted from hairs inhibited the PCR of the genomic DNA template when added to the PCR reaction at the concentrations over than 15 ng/100 microL. Therefore, typability of hair shaft portions seems to depend on the delicate balance of the concentrations of DNA and the contaminated melanin in the final DNA extracts.

A numerical model of a fluidized bed reactor was developed for estimating rates of CVD and fines formation in polycrystalline silicon production from monosilane. In the model, Kunii-Levenspiel fluidized bed model and reaction kinetics were combined. The model predicts both the homogeneous decomposition to give fine powder and the heterogeneous CVD on seed silicon particles. The relative and quantitative contributions of both reactions were elucidated in fluidized bed bubbling zone including both bubble and emulsion phases. The present model also predicts the effects of operational conditions on the rates. The numerical values were compared with experimental data by ourselves and Hsu et al. The results indicated that fines mainly form in the bubble phase.

Publisher Summary In a coke oven chamber, the coking of coal charge is conducted batchwise. This chapter discusses a study in which a tracer technique using He and Ar was employed to investigate the paths of travel of gases produced in a test coke oven especially in the coal layer because the coal layer is thought to be mostly surrounded by the impermeable plastic zone. The variation in temperature distribution in the charge with elapse of time was monitored. The position of the plastic layer was predicted by assuming that it exists between the positions at 385°C of Soft T and 465°C of Solid T. A small amount of argon was detected from the center and helium was slightly found from the wall side as well, which suggests the small amount of cross flow through the plastic zone. In the middle of the stage, helium mostly flowed toward the door of coke side. After the plastic zone reached the center of the charge and disappeared, the maldistribution of tracer gases was hardly found, suggesting that the produced gas passed through the coke layer uniformly.

Characterization of polycrystalline silicon particles produced in a fluidized bed reactor via CVD from monosilane was carried out. It was observed that part of the hydrogen from monosilane remained in the particles. Most of hydrogen was bonded to silicon and temperatures as high as 1300 K were required to dehydrogenate the silicon particles. Particles were contaminated with metal elements which were diffused from the reactor wall, suggesting that the material used in constructing the fluidized bed reactor wall also needed to be controlled to improve the purity of product.

A plasma jetting fluidized bed reactor was developed for coating particles via PCVD. Conversion of methane was carried out to investigate characteristics of this type of reactor. It was found that introduction of reactive gases from the side of a d.c. plasma jet resulted in no deterioration of the stability of plasma and that the reactive gases were effectively activated even in the presence of particles. Particles packed in the reactor promoted reactions to give carbon in the presence of hydrogen in a large excess, strongly suggesting that PCVD on fluidized particles can be realized.

The fluidized bed CVD process for the polycrystalline silicon production is considered to be the most attractive alternative to the conventional bell-jar process. The employment of a reaction path starting from monosilane has various merits over the conventional reaction path starting from trichlorosilane. In the present study, chemical vapor deposition of polycrystalline silicon on seed particles was conducted in a experimental fluidized bed reactor by thermal decomposition of monosilane diluted with hydrogen. The bed temperature was gradually increased and the conversion at the temperature was measured. The apparent first order reaction rate constant of monosilane pyrolysis in the bed was determined and the activation energy was found to be almost the same as that of heterogeneous deposition reaction rate constant. Optimum process conditions for stable and effective operation were determined. Lastly the continuous operation was conducted for more than 100 min. without any trouble and with the least fines elutriation under the optimum condition determined above.

Publisher Summary This chapter presents the determination of progress of chemical reactions in the grid zone of a fluidized bed gasifier of coal char. Operation of coal gasifier at around 1300°C is considered to be optimum for energy efficiency, carbon efficiency, gas composition, and ash treatment. Both systems of fluidized bed and entrain bed are under research and development. Fluidized bed coal gasifiers are usually operated at around 900°C because softening of coal ash at higher temperatures gives rise to serious operational troubles. In a study described in the chapter, the coal sample used was Taiheiyo coal char produced by pyrolysis at 400°C. The results indicated that a part of gas was exchanged between the jets. Taking it into account that the initial molar ratio of steam to helium was 1/10, local levels of steam conversion were evaluated from the observed ratio of hydrogen to helium on the assumption that steam, hydrogen, and helium comparably diffused under the experimental conditions used. When no air was injected, CO was predominantly produced in the middle part of the bed and the water–gas shift reaction proceeded with height, and was almost equilibrated at the upper part of the bed.

The permeation rates of Nd and Pr ions through a supported liquid membrane (SLM) in the absence and presence of complexing agents in the stripping phase were studied. It was found that permeation of both Nd and Pr ions was accelerated by a complexing agent irreversively incorporated into the SLM.

The fertilization of the ocean with nutrients such as nitrate and/or phosphate is studied as one of the measures for solving the CO 2 problem in this paper. The desired amounts of nutrients were calculated based on the Redfield ratio of the phytoplankton in the ocean. Then, the dynamic decrease in the atmospheric CO 2 concentration by fertilization was estimated, using the unsteady state model developed by modifying the conventional two box model. The calculation results indicated that atmospheric CO 2 can be absorbed quickly, within a few years, by the fertilization. The estimation of energy requirements also indicated that this technique is feasible from the viewpoint of the energy balance.

Minisatellite variant repeat (MVR) mapping using the polymerase chain reaction (PCR) at D1S8 (MS32) was applied to samples from various human tissues. All DNA samples obtained from an individual's organs at autopsy consistently gave the same digital diploid codes. Even 1 ng of genomic DNA was sufficient to obtain authentic diploid MVR coding ladders. MVR-PCR could be reliably applied to DNA isolated from bloodstains, saliva stains, seminal stains and plucked hair roots, and should become a powerful tool for individual identification in forensic investigations.