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Biopolymers are easily denatured by heating, a change in pH or chemical substances when they are immobilized on a substrate. To prevent denaturation of biopolymers, we developed a method to trap a polynucleotide on a substrate by hydrogen bonding using silica particles with surfaces modified by aminoalkyl chains ([A-AM silane]/SiO2). [A-AM silane]/SiO2 was synthesized by silane coupling reaction of N-2-(aminoethyl)-3-aminopropyltrimethoxysilane (A-AM silane) with SiO2 particles with a diameter of 5 μm at 100 °C for 20 min. The surface chemical structure of [A-AM silane]/SiO2 was characterized by Fourier transform infrared spectroscopy and molecular orbital calculations. The surface of the silica particles was modified with A-AM silane and primary amine groups were formed. [A-AM silane]/SiO2 was trapped with single-stranded nucleic acids [(Poly-X; X = A (adenine), G (guanine) and C (cytosine)] in PBS solution at 37 °C for 1 h. The single-stranded nucleic acids were trapped on the surface of the [A-AM silane]/SiO2 by hydrogen bonding to form conjugated materials. The resulting complexes were further conjugated by derivatives of acridine orange (AO) as fluorescent labels under the same conditions to form [AO:Poly-X:A-AM silane]/SiO2 complexes. Changes in the fluorescence intensity of these complexes originating from interactions between the single-stranded nucleic acid and aromatic compounds were also evaluated. The change in intensity displayed the order [AO: Poly-G: A-AM silane]/SiO2 > [AO:Poly-A:A-AM silane]/SiO2 >> [AO:Poly-C:A-AM silane]/SiO2. This suggests that the single-stranded nucleic acids conjugated with aminoalkyl chains on the surfaces of SiO2 particles and the change in fluorescence intensity reflected the molecular interaction between AO and the nucleic-acid base in a polynucleotide.

Background and Objective: In the present study, micro-channel arrays were fabricated on the surface of plastic-based disposable chips. The cell adhesion process and the detection of plaque-forming macrophages were observed. Further, we evaluated cell adhesion in a fluid system in vitro. Material and Methods: Features of the micro-channel (1.4 mm wide and 10 mm long) included twenty micro-pillars (with a projection of 200 μm diameter and 250 μm high) coated in a 50 μm thick silicon rubber layer, which were regularly arranged at the bottom of each channel. The efficiency of cell capture was expected to increase by arrangement of micro-pillars in a micro-channel. Mouse macrophage RAW264.7 cells, stimulated for 24 h with lipopolysaccharide (LPS) derived from periodontopathic bacteria, were circulated continuously for 2 h at room temperature by the pump in a chip. Results: Control cells had not formed plaques on micro-pillars 20 min into the experiment. By contrast, LPS-activated macrophages produced plaques at the side walls of micro-pillars after 20 min. The plaques grew during the flow test, and image shading became clearer with increasing flow time for 120 min. The maximal adhesion rate per unit area appeared at 20% for control cells, whereas the peak was shifted to 30% for LPS-activated macrophages (n = 20). The average adhesion rate was 3.0 ± 2.0% for control cells and 5.0 ± 3.9% for LPS-activated macrophages (n = 100). Conclusion: These findings indicate that LPS-activated macrophages accumulate in micro-channel arrays, and suggest that macrophage plaque formation is a two-step procedure: (1) LPS-activated macrophages adhere physically to the silicon rubber layer on micro-pillars; and (2) consequently, the cells adhere to the activated macrophage layer.

This study describes some of the influencing factors, such as capillary action, static electricity and magnetic force, on the ability to separate living leukocytes from a single droplet of blood ( The chip was constructed from two substrate materials sandwiched together to form a micron-order gap (40 μm) with an upper hydrophilic (glass) surface and a lower hydrophobic (acrylic resin) surface. A blood sample flowed into the gap between the two substrates driven by the difference in surface tension between the two materials. Leukocytes adhered to the lower hydrophobic surface, whereas red corpuscles flowed toward the exit of the microfluidic device (this phenomenon is referred to as micro-flow). The separation rate of the red corpuscles was 91 ± 9% in a unit area of 0.1 mm2. Furthermore, we analyzed the change in the numbers of living leukocytes that could be collected after separation in the chip under different conditions. When SiO2 and iron composite particles, 10 μm in size, were added to the blood sample, leukocytes formed colonies containing two or three cells. The colonies could be moved freely on the x–y plane using a Nd magnet. When the upper board was charged by static electricity, the colonies adhered to the underneath of the upper board. Five or more colonies, as well as 10 or more individual leukocytes, were able to collect in a 0.1 mm2 area of the chip after micro-flow operation. Thus, the separation efficiency of a living cell colony containing Fe particles in a capillary chip is markedly influenced by magnetic and electrostatic forces.

The detection of antigen–antibody reactions in normal saline solution, measured using a chip-mounted source-drain electrode coated with an insulation layer with immobilized antibody or antigen molecules, was investigated as a function of concentration. Five pairs of source-drain electrodes (×8 arrays) were fabricated on a glass substrate of 20 mm × 30 mm size, in which the individual Au/Cr (1.0/0.1 μm thickness) sensors had widths of 50 μm, and an inter-electrode interval of 100 μm. The fabricated source-drain electrodes were further coated with an insulation layer comprising various porous materials for use as an adsorbent for receiving antibody molecules. The sensor chip was equipped with a handy-type sensor signal analyzer that comprised either an amplifier circuit with a Miniship™, or a system in a packaged LSI device. The weak current received by each sensor electrode was amplified and modulated with a sensor signal analyzer to give a digital signal, which was then wirelessly transmitted to a PC connected to a receiver device. The effects of the immobilized antibody molecules on the detection selectivity and detection limits were examined. The sensing functions were determined by measurement of the source-drain electrode voltage when the surface of the insulator was contacted with antigen solutions of various concentrations. The sensor ability was also evaluated by comparing the relative selectivity of each sensor. When a sensor surface with immobilized biotin was used for avidin sensing, or immobilized with leukotriene B4 for anti-leukotriene sensing, the sensor showed the largest effect for the selective detection of all sensor testing conducted. In contrast, when the sensor surface was immobilized with avidin for biotin sensing, or immobilized with anti-leukotriene for leukotriene sensing, the sensor exhibited low selectivity. Based on the results obtained, an adsorbed antibody on an adsorption particle is effectively expressed as the selective detection ability for the sensor-array chips. When liquid is deposited on the surface of an insulator, an electric double layer arises at the boundary surface. In this respect, the insulator molecules become polarized, resulting in the formation of opposing charges on both the boundary surface between the liquid and solid, and on the reverse side of the insulator. In the same way, when a solution mixture containing antigens is deposited on the surface of an insulator with antibodies immobilized to its surface, specific antigens and antibody reactions occur and the charge on the reverse side of the insulator is increased. The relationship between the source-drain electrode current and the sensor voltage follows Ohm's law. Based on this principle, a source-drain electrode produces a signal in response to changes in current originating from antigen–antibody reactions at the boundary surface on the insulator layer. The avidin molecule is composed of four domain structures, such that, four acceptors per molecule exist on the surface of the adsorbent particle. Biotin preferably interacts with this acceptor, because the molecular size of biotin is smaller that that of avidin. The sensor voltage changes do not suffer in the presence of cation contamination. In contrast, the molecular size of avidin is much larger than that of the cations in solution. In this respect, the cations are considered to interact with the sensor surface in preference to the biotin antibodies, thus promoting polarization of the insulator layer. As a result, the detection voltages increased, while the detection selectivity decreased.

A chip-mounted source–drain electrode coated with an insulator layer was investigated with respect to its ability for monitoring in a concentrated nitrate ion solution. Exposing the electrode surface to highly concentrated nitrate ion solutions resulted in an increase in the detection voltage, while weakly concentrated solutions caused the detection voltage to decrease. Semi-circular shaped microelectrodes consisted of an Au/Cr film of 1/0.1 μm thickness on a glass chip, constructed using photolithography. A novolac resin or fluoro-olefin vinyl ether copolymer was used as the precursor of an insulator layer on the source–drain electrode. NaNO3 solutions of 1.0 × 10−6 to 1.0 mol l−1 (1 μl) were applied to the insulated electrode, and the chemical sensitivity was evaluated by measuring the detection voltage. The effects of thickness, insulator type, solution, and sensor material, on the chemical sensitivity were investigated. For a novolac resin insulator layer of thickness 5 μm) resulted in a sensor voltage that showed a linear response depending on the NaNO3 concentration in the range of 1.0 × 10−6 to 1.0 × 10−3 mol l−1. The responsiveness of the sensor was improved with increasing insulator layer thickness. Optimization of the insulator thickness is therefore necessary if an effective sensor is to be realized. Sensor detection was also effected by the kind of solution and electrode material. The placing of a liquid droplet on the insulator surface resulted in the formation of an electric double layer at the boundary surface. Here, the molecules within the insulator become polarized, and a charge is formed at the boundary surface between the liquid and solid, and on the reverse side of the insulator. In this case, the relationship between the source–drain electrode current and the sensor voltage follows Ohm's law. Based on this principle, a source–drain electrode produces a signal in response to changes in current originating from polarization of the insulator layer.

A microelectrode sensor mounted on a chip was investigated regarding its properties for detecting optical intensity. Comb-like shaped microelectrodes were constructed by a photolithographic method and consisted of a Cu film of 10 μm thickness on a resin chip. Three comb-like electrodes with varying comb numbers were fabricated; lengths were: a = 10 mm (8 combs), a = 5 mm (4 combs), and a = 2.5 mm (2 combs). NaCl solutions of 1.0 × 10–4 to 1.0 mol l–1 (2–10 μL) were applied on the microelectrode under white light irradiation of 0–1.5 × 103 lx emitted from an LED. Optical sensitivity was then evaluated by measuring the electrical resistance. The effects of electrode size and sensor material on the detection limits for optical sensitivity were investigated. The sensor responded to changes in light intensity when an electrolyte solution contacted the surface of a pair of comb-like electrodes. When a strong light was irradiated onto the microelectrode in contact with an NaCl solution, the electrical resistance markedly reduced. By contrast, when a weak light was irradiated on the microelectrode in contact with an NaCl solution, the electrical resistance increased. When the sensor size or the number of combs was increased, electrical resistance showed a marked decrease with increased light intensity. In particular, an eight-comb microsensor exhibited high responsiveness under weak light intensity within the range of 0–1.0 × 103 lx. When the electrolyte concentration is constant, electrical resistance also converges to a constant value. In all the various upper boards tested (polyimide, silicon rubber, glass, and PET film), the resistance value depended on the thickness regardless of the intensity of light irradiation. The various materials showed no effect on light intensity. However, the electrical resistance of the sensor increased for upper boards made of Teflon, polypropylene, and polychlorovinylidene for which electrical resistance was reduced when light intensity was high. It is suggested that polarization occurs when light is irradiated onto a metal sensor surface and the boundary surface of an electrolyte droplet. In the presence of a constant electrolyte concentration, the charge distribution on the surface of the sensor was found to change in accordance with the intensity of light irradiation. These results clearly demonstrate that photosensitivity and ion sensitivity, as well as the formation of the ion layer, are influenced by the choice of the cover material. We applied a microelectrode as an optical detector for a microarray to measure the concentration of a dye such as methylene blue. We measured the electrical resistance values, as well as those of light intensity, of four microelectrodes located on the reverse side of a microarray. Methylene blue solution was prepared at concentrations of 0, 1.0 × 10–3, 1.0 × 10–2, and 1.0 × 10–1 wt% and 50 μL of each solution was applied to each of the microarrays. The upper board material was translucent and irradiated light could pass through the microarrays including the dye solution. The light that penetrated was received by each microelectrode, as well as a photosensor located under microarray. In each of the microarrays, the detection voltage of the microelectrode depended on the depth of the sample color.

A micro-electrode sensor mounted on a chip is developed to measure the concentration of non-electrolytes contained in a single drop of an ion solution. The sensitivity of the microsensor, as well as the detection of the electric resistance or voltage, depends on the size of the electrode and the kind of coating metals. The size of the Cu microsensor is optimized at 3.5 mm long, 200 μm wide and an interval of 700 μm. The electric resistance and conductivity of the optimized microsensor relates well to the concentration of electrolytes such as NaCl or glycine, within a concentration range of 10 −4 to 1 mol l −1 . Substance detection using a microsensor is within 100 ms, with a repetition precision of ±1.8 to 3.9%. The effects of additives in a single drop of a solution containing nucleic acids are also measured as model non-electrolytic substances to prevent the detection by buffer ions. Nucleic acids are preferentially adsorbed and are detectable by the microsensor when the adsorbent consists of polystyrene micro-particles with a schizophyllan-modified surface. Non-electrolytes in an ion solution are also measurable by the microsensor with adsorbents in a droplet.

We previously developed a microsensor consisting of a pair of electrodes (2 mm f) capable of measuring ion concentrations in NaCl, amino acids or nucleic acid solutions (1 nl 1 m l). Of minimal size and with a simple structure it has an enormous advantage in that it can easily be mounted on a flat chip or surface. The microsensor can detect changes in voltage or conductivity when the ion concentration is altered in a drop of NaCl, amino acid or nucleic acid solution on the sensor surface. The electrical resistance of the optimized microsensor is capable of detecting NaCl concentrations within the range of 1.0 10 4 1.0 mol l . We have also reported that the microsensor is responsive to changes in light intensity when an electrolyte solution is applied to the microelectrode surface during white light irradiation, with the optical sensitivity observed being similar to that displayed by certain CdS semiconductor sensors. In this study, we aimed to develop a microsensor chip that can detect both chemical concentration and light intensity. We now report the effects of the packaging materials on the limits of detection of NaCl concentration and optical sensitivity irradiated on the microelectrode. 2. Experiments

Recently, a fluid micro electro mechanical system (fluid MEMS), which is composed of a micro pump, mixer, valve, reactor, sensor, an electric circuit, on a chip, is being applied to a biotechnology or a medical analysis. Authors developed a micro sensor mounted on a chip to measure a concentration of one drop of solution (1nL-10μL) which contained nuclear acids. The form of the micro sensor mounted on the chip was a pair of Cu electrode which was a diameter of 2mm and was a thickness of 10μm. The sensing function was evaluated by the changes in a concentration of poly(x) (x=adenine, guanine, uracil, and cytosine) solution which was dropped on a micro sensor.To increase a recognization against nucleic acid, various adsorbent was added in a droplet. Especially, high recognition against the nucleic acid was observed with the adsorbent which modified the surface of polystyrene micro beads(10μm) using schizophyllan: a kind of polysaccharide. This biosensor recognized a small quantity of total-RNA and m-RNA extracted from the yeast.

Recently, a fluid-micro electro mechanical system (fluid MEMS), composed of a micro pump, mixer, valve, reactor, sensor, an electric circuit, on a chip, is being applied to biotechnology or medical analysis. The authors have been proposed a micro chemical sensor which can be mounted on a fluid MEMS chip to measure the concentration of small liquid samples (1 nL-1 μL) . This paper reports on the development of the micro photosensor which can analyze the concentration of small biochemical sample. The micro photosensor formed on a chip consists of thin Cu electrodes in a comb shape. The electrical resistance of the micro-sensor is related to the concentration of the solution in contact with the electrodes. In addition, the electrical resistance of the micro-sensor in contact with the solution is related to the intensity of light irradiated on to the surface of the electrode. This micro photosensor can detect the light which penetrats colored biochemical sample such as blood.

触媒素反応機構の分子シミュレーション解析によって, 水素化脱硫 (HDS) ならびに水素化脱窒素 (HDN) 反応に代表される石油精製反応の素反応モデルを考察した一連の成果をまとめた。水素化精製触媒の活性点は, 現在ではMoS2微結晶のエッジ部に形成されるCo-Mo-S相であるという説が広く支持されている。ここでは, (1) 気相H2の吸着•解離, (2) S化合物(基質分子) の配位, (3) C-S結合の開裂, (4) 生成物脱離の各ステップを経て, 反応が進行すると予想される。しかし, 実際の反応条件下で, このような活性点における触媒作用機構は明らかではない。これには反応に最も寄与する基質側の分子軌道の解明, ならびに活性点側の電子状態を概観した上で, 基質-活性点相互作用を議論する必要がある。そこで素反応モデルとして, ジベンゾチオフェンのHDS反応過程を分子軌道計算し, 化学反応律速の検証を行った。同様にアクリジンのHDN反応シミュレーションへの適用も試み, 触媒活性点における分子反応機構を提案した。

Upper Freeport coal was extracted using a mixture of carbon disulfide and N-methyl-2-pyrrolidinone (CS2/NMP) under ultrasonic irradiation at room temperature. The CS2/NMP-soluble fraction (CS2/NMP-...

Skeletal isomerization of 4,6-dimethyldibenzothiophene (4,6-DMDBT) was performed at 270 °C for 1 h at a hydrogen pressure of 2.5 MPa using a Ni-supported Y-type zeolite catalyst. Alkyldibenzothiophenes (alkyl-DBTs), which were produced by methylmigration and transalkylation, were further desulfurized at 255−300 °C for 2−120 min at a hydrogen pressure of 2.5 MPa using a CoMo/Al2O3 catalyst. The produced alkyl-DBTs, which carried 1−3 methyl groups, could be classified into three groups on the basis of activation energy for desulfurization. Group I included 2,8-DMDBT and C1-DBT, which carried no methyl groups at either the 4- or 6-position. Group III included unreacted 4,6-DMDBT, and group II contained other alkyl-DBTs with 1−3 methyl groups. No alkyl-DBTs with 4 methyl groups were found in the products of 4,6-DMDBT. The steric hindrance of the methyl groups on 4,6-DMDBT was relieved by methylmigration and transalkylation, and, as a result, the desulfurization activation energy, 37.2 kcal/mol, for 4,6-DMDBT ...

Illinois No. 6 coal was depolymerized by treatment with trifluoromethanesulfonic acid in methylcyclopentane at 120 °C. The yield of tetrahydrofuran (THF) extract was increased to 89 wt %. This incr...

Toluene, phenol, benzyl alcohol, and benzoic acid in alcohols were hydrogenated using Ru/Al2O3 and Pt/Al2O3 catalysts at 120 °C under a hydrogen pressure of 6 MPa. The Ru/Al2O3 catalyst exhibited a high activity for hydrogenation of mono-aromatics dissolved in alcohols. The hydrogenation activity of the Pt/Al2O3 catalyst was strongly inhibited by the presence of alcohols. To evaluate the role of solvents, nonpolar and polar solvents, some of which contained oxygen, sulfur or nitrogen, were used for the hydrogenation of benzyl alcohol over the Ru/Al2O3 catalyst. A relationship was found between the hydrogenation reactivity of benzyl alcohol in polar solvents and the δ value of the solvent, as defined by the difference between donor number and acceptor number. Nonpolar solvents had no effect on the hydrogenation reaction of benzyl alcohol. Polar solvents with negative δ values, such as methanol, ethanol, and acetic acid, also had no effect. However, polar solvents with positive δ values, such as acetone, te...

Yallourn, Taiheiyo, South Banko, Miike, and Hunter Valley coals were pyrolyzed using a Curie-point pyrolyzer at 500−1040 °C. Product distributions were determined by GC-TCD and GC-FTD, and N2 evolved in the gas phase was analyzed using a quadrupole mass spectrometer. Samples were also prepared by mildly oxidizing Yallourn coal and hydrogenating the resulting ethanol soluble over a Ru/Al2O3 catalyst. Quinoline and hydrogenated quinolines were also used as models in order to better understand the role of the heterocyclic structure in denitrogenation during pyrolysis. More than 90 mol % of the nitrogen atoms in the coals remained in the char and tar as a result of the pyrolysis of the raw coals. However, the heterocyclic structures of the raw Yallourn coal were partially changed by hydrogenation over a Ru/Al2O3 catalyst, and this alteration enhanced the cleavage of those structures during pyrolysis, decreased the nitrogen content of the char, and increased the yield of nitrogen compounds in the gas phase.

The hydrocracking of pyrene (Py) was examined in a batch autoclave at 386 °C for 0−30 min under a hydrogen pressure of 5 MPa, using a Ni-supported Y-type zeolite (Ni−HY) catalyst. The hydrocracking...

Polyethylene was thermally cracked at 425, 450, and 475 °C in nitrogen at atmospheric pressure for 10-120 min. The major components of the oil were straight-chain olefins which contained 4-25 carbons. Pyrolysis at lower temperatures for shorter reaction times produced straight-chain olefins with a broad distribution of carbon atoms, and pyrolysis at 450 °C for 60 min or under more severe conditions produced mainly straight-chain olefins containing 4-12 carbons. The reaction at 475 °C produced C 1 -C 4 hydrocarbon gases and coke by the secondary cracking and polymerization. The oil was then cracked over catalysts at 500 °C for 2 s at a heating rate of 3000 °C/s using a Curie-point pyrolyzer in a flow of helium at atmospheric pressure. Metal-loaded and dealuminated Y-zeolites as well as aluminosilicate MCM-41 were prepared and examined as cracking catalysts, and their catalytic activities and selectivities were compared to those of conventional zeolite catalysts. Aluminosilicate MCM-41 of Si/2Al = 25 and Ni-HY zeolite of Si/2Al = 50 exhibited a mild cracking activity, giving products of the middle distillate range with no coke deposition. The metal-loaded and metal-free HY zeolites of Si/2Al = 16 exhibited an excessive cracking activity, producing C 5 -C 7 olefins with coke deposition, n-Octadecane was used as the model compound and was cracked over the catalysts under the same conditions as those used for the polyethylene oil. The reactivity of the catalysts was well-correlated with the amount of NH 3 adsorption per unit catalyst area. The metal-supported dealuminated Y-zeolites and aluminosilicate MCM-41 possessed less aluminum atoms and, as a result, a smaller number of acidic sites. The removal of aluminum atoms from the zeolite framework and the control of the acidity are thus key factors in achieving mild cracking of the paraffinic oil.

In the present part of the group study on the preparation of 13 wt% MoO3/Al2O3, the effects of drying processes were investigated on the physicochemical and catalytic properties. Two series of catalysts were prepared by a conventional impregnation technique and by an equilibrium adsorption method using a common extrudate support. XPS and EPMA results demonstrated that the distribution of Mo oxide species in extrudates was strongly affected by drying processes. A rapid drying, in particular at a reduced pressure, was found to induce a strong segregation of Mo oxides on the outer surface of the extrudates, forming a sharp egg shell type distribution of Mo. On the other hand, drying under static conditions produced a moderate egg shell type distribution, suggesting that a slow drying rate is favorable for a homogeneous distribution of Mo. The equilibrium adsorption technique was found to provide considerably flat Mo profiles inside the extrudates except for the utmost surfaces where Mo concentrations increased steeply.

Ten types of 13 wt% MoO3/Al2O3 catalysts were prepared by a conventional impregnation or equilibrium adsorption method using a common extrudate support. These catalysts were subjected to a comprehensive characterization and catalytic reactions to find important preparation parameters in practical preparations. It was demonstrated in the present group study that the formation of crystalline MoO3 was strongly correlated with the Mo segregation on the outer surface of the extrudate. When the amount of the impregnation solution was large (ca. 10 cm3 g-Al2O3−1), a considerably homogeneous distribution and high dispersion of Mo oxide species were attained irrespective of the other preparation parameters. It is suggested that when a pore volume impregnation or incipient wetness technique is employed, drying processes strongly affect the dispersion and distribution of Mo oxide species. Drying at a reduced pressure is suggested to result in a segregation of Mo oxides on the outer surface of the extrudate, and accordingly a formation of crystalline MoO3.

Hydrocracking, hydrodenitrogenation (HDN), and hydrodesulfurization (HDS) of vacuum gas oil (VGO) were examined using Ni-, Co-, and Fe-loaded and dealuminated Y-zeolites at 300−380 °C under an initial hydrogen pressure of 5 MPa. The major fraction of the VGO was n-paraffins (45 wt %), and the second major fraction was alkyl-substituted 3- and 4-ring aromatics. Polar aromatics and 1- and 2-ring aromatics were minor components. Paraffins of 15−32 carbon chains and aromatic compounds of 3−4 rings were efficiently hydrocracked into a gasoline fraction over Ni−HY-A (Si/2Al = 16.0) zeolite, which gave the least yield of gaseous byproducts among the catalysts examined. Extensively dealuminated Ni−HY-B zeolite (Si/2Al = 50.0) produced a large amount of middle distillate fraction, while the yields of gas and coke that was deposited on the catalyst were markedly suppressed. Both zeolites exhibited excellent HDN and HDS activities. The Co−HY and Fe−HY zeolites showed a similar hydrocracking activity as did the Ni−HY...

Yallourn coal was oxidized in aqueous H 2 O 2 in the presence of 1-propanol at 70 °C for 6 h under atmospheric pressure. The coal was partially decomposed by the OH radicals formed from H 2 O 2 , and carboxy and methylene groups originating from H 2 O 2 and 1-propanol were added to the coal structure. As a result, the solubility of the coal in ethanol was increased to 80 kg per 100 kg of the raw coal. The H/C ratio, which was 0.95 for the raw coal, was increased to 1.07 by the oxidization in the presence of 1-propanol. The ethanol-soluble fraction of the oxidized coal was then hydrogenated using a Ru/Al 2 O 3 catalyst in a mixed solvent of ethanol and acetic acid at 120 °C for 12-72 h at a hydrogen pressure of 10 MPa. After the hydrogenation, a yellowish white solid (hereafter referred to as hydrogenated white coal) was obtained. Major gaseous products were CO and CO 2 , and the yield of these gases produced by the hydrogenation in the presence of acetic acid was less than 3 kg per 100 kg of raw coal. The H/C ratio of the hydrogenated coal increased with increasing hydrogenation time and amount of acetic acid and was 1.23 after a 72 h reaction. The hydrogenation also decreased the total nitrogen content in the raw coal. The denitrogenation increased with increasing hydrogenation time and reached 60% after 72 h. It is noteworthy that this conversion was attained by a reaction at 120 °C. The IR peaks at 3000 and 2900 cm -1 , assigned to methylene group, were increased by the hydrogenation. Further structural analyses of the hydrogenated white coal indicated that aromatic rings were changed to saturated rings, i.e., that the sp 2 bonding structure of the coal was transformed to the sp 3 bonding structure. In order to better understand the hydrogenation mechanism, benzyl alcohol, benzoic acid, phenol, and toluene were hydrogenated as model compounds, representing the structure of the alcohol-soluble fraction of the oxidized coal. The addition of carboxylic acids greatly enhanced the hydrogenation of aromatic rings in the model compounds over the Ru/Al 2 O 3 catalyst. The molecular orbital calculation, based on the WinMOPAC program, suggested that dipole moments and charges on the oxygen atoms of carboxylic acids played important roles in the above transformation of the coal structure.

軽油中に含有される難脱硫性硫黄化合物4,6-ジメチルジベンゾチオフェン (4,6-DMDBT) をn-デカン中, 270°C, 水素圧2.5MPaでNi担持Y-ゼオライト (Ni-HYゼオライト) を用いてメチル基の異性化反応を行い, 引き続き中間体であるアルキルジベンゾチオフェン類 (Cx-DBT) を同反応条件でCoMo/Al2O3で脱硫し, それらの脱硫反応速度を算出した。また, 反応中間体の構造を決定するため, 数種類のアルキルジベンゾチオフェン類を合成した。このようにして構造決定できたアルキルジベンゾチオフェン類の脱硫反応速度の実測値と, 分子軌道計算で得られた硫黄原子上の電子密度との関係を考察し, ゼオライトによるメチル基転位反応が難脱硫性硫黄化合物の脱硫反応性に及ぼす影響を調べた。Ni-HYゼオライトによる異性化反応で生成した側鎖炭素数1～4のアルキルジベンゾチオフェン類は, 脱硫反応速度の違いにより以下の4グループに分類できた: 4,6-DMDBT (グループI)

Sulfur compounds in the non-polar fraction, which represents 73 wt% of total sulfur in a vacuum gas oil (VGO), were analysed by sulfur-selective ligand exchange chromatography combined with high-performance liquid chromatographic (h.p.l.c.) separation on the basis of aromatic ring number, with subsequent capillary g.c.-mass spectrometry for identification. Quantification was achieved by independent h.p.l.c. separation based on aromatic ring number followed by capillary gas chromatography with a sulfur-selective flame photometric detector. These methods were very effective in isolating the sulfur compounds from complex mixtures of high-boiling hydrocarbon compounds and for separating the sulfur compounds according to aromatic ring number. The structures and concentrations of > 100 sulfur compounds in the non-polar fraction of the VGO were determined Alkyl benzo[b]thiophenes, dibenzo[b,d]thiophenes, benzonaphthothiophenes and phenanthro[4,5-b,c,d]thiophenes were found to be major sulfur species existing in the non-polar fraction of the VGO.

The catalytic activities of NiMo Al 2 O 3 and CoMo Al 2 O 3 with a variable content of Ni and Co, respectively, were examined for the hydrodesulfurization (HDS) of refractory sulfur species, 4,6-dimethyldibenzothiophene (4,6-DMDBT), in decane with naphthalene. Naphthalene of 10 wt.−% severely retarded the HDS of 4,6-DMDBT over the series of NiMo catalysts. Hydrogenation of naphthalene dominated over the series of NiMo catalysts, suppressing the HDS of 4,6-DMDBT over the catalysts. CoMo catalysts were superior to the NiMo catalysts for the HDS activities of 4,6-DMDBT with less retardation of the aromatic partner, providing the highest activity at Co content of 1 wt.−% in 15 wt.−% of Mo, although the former catalysts were inferior to the latter ones for the hydrogenation activities of the aromatic partner. The valence states of metals were observed by X-ray photoelectron spectra (XPS) to discuss the active sites for the hydrogenation especially selective to the sulfur species.

Deep hydrodesulfurization (HDS) of diesel fuel oil was designed based on the recognition that alkyl dibenzothiophenes such as 4-methyl-and 4,6-dimethyldibenzothiophenes were the main target for deep HDS. Multi-stage and fractional HDS were very effective to achieve satisfactory HDS in terms of both sulfur level and fluorescent color of desulfurized oil. Catalysts with the selective hydrogenation of refractory sulfur species in major aromatic partners and isomerization-disproportionation of their alkyl groups prior to HDS were also designed to promote the desulfurization of such sulfur species.

The catalytic activities of sulfided Ru−CoMo/Al2O3 were examined for the desulfurization of 4,6-dimethyldibenzothiophene (4,6-DMDBT) in decane and decane with naphthalene to find selective catalysts which desulfurize 4,6-DMDBT in the presence of naphthalene through preferential hydrogenation of its phenyl ring. Addition of Ru to CoMo catalyst exhibited an excellent activity for HDS of 4,6-DMDBT and suffered less inhibition by coexisting naphthalene, whereas significant retardation was observed over NiMo/Al2O3 and Ru−NiMo/Al2O3. The ternary combination required much less amount of Ru to maximize the selective HDS reaction, compared to the blend of Ru/Al2O3 and CoMo/Al2O3. Several structural characteristics of the ternary catalyst were revealed according to XPS and HREM: (1) Mo and Ru existed separately on the same alumina support in forms of respective sulfides, (2) crystal size of MoS2 increased when Ru was present on the same support, and (3) MoS2 was easily reduced in the presence of Ru. RuS2 is sugges...

The fluorescence color of a gas oil and its desulfurized oils was evaluated by using a fluorescence spectrophotometer. The visible-fluorescence species existing in the deeply desulfurized oil were separated by HPLC and identified by GC-MS (mass spectrometry), and their fluorescence emission spectra were examined and compared with those of representative polycyclic aromatic hydrocarbons. Anthracene, fluoranthene, and their alkyl derivatives are concluded to be major fluorescence species existing in the desulfurized oil at the concentration of about 10 ppmw. The color of oil was easily removed by their partial hydrogenation over NiMo catalyst at a relatively lower temperature of 280 °C for 10 min under a low hydrogen pressure of 2.9 MPa. The partial hydrogenation was ascertained to remove the fluorescence color of the model compounds.

Hydrodesulfurization (HDS) reactivity of a refractory sulfur species, 4,6-dimethyldibenzothiophene (4,6-DMDBT), was examined over a Y-zeolite containing CoMo/Al2O3 (CoMo/Al2O3-zeolite), conventional CoMo/Al2O3, and NiMo/Al2O3. Isomerization and considerable transalkylation of 4,6-DMDBT into 3,6-DMDBT and into tri- or tetramethyldibenzothiophenes, respectively, were observed characteristically over CoMo/Al2O3-zeolite catalyst. Migration of methyl groups enhances the HDS reactivity of the refractory sulfur species by diminishing the steric hindrance. Among the catalysts examined, CoMo/Al2O3-zeolite exhibited the best activity for HDS of the gas oil through the effective desulfurization of refractory alkyldibenzothiophenes.

The solution properties of various double-chained anionic surfactants [disodium 5, 12-bis (2-alkyloxymethyl) -4, 7, 10, 13-tetraoxa-1, 16-hexadecanedisulfonate ; 2CnElS3, n=8, 10, 12, 14] with two anionic groups, differing in alkyl chain lengths, were examined by surface tension, micellar diameter, aggregation number and pNa measurements.Critical micelle concentration (cmc) and minimum surface tension at cmc (γcmc) decreased with an increase in alkyl chain length. At the same alkyl chain length, these parameters were less than those of anionic surfactants with single chains and single ionic groups. Micellar diameter (HD), aggregation number (N), occupied area of the hydrophilic group on the micellar surfaces (A) all showed maximum values at n=10. The degree of ionic dissociation of micelles (α) decreased with increasing alkyl chain lengths.Molecular packing on the micellar surfaces was found to depend on the steric structure of the bridge part in the surfactant molecule.

The relative hydrodesulfurization reactivities of heterocyclic sulfur compounds collected from our experiments and the literature were correlated with their electronic parameters estimated using MOPAC-PM3. It is found that the direct hydrogenolytic S elimination (direct hydrogenolysis) of sulfur-containing compounds is definitely correlated with the electron density of their S atoms, while the hydrogenation of the thiophenic ring or neighboring ring prior to hydrogenolysis correlated with the bond order of the most unsaturated bond in the ring. Methyl groups at 4-and/or 6-positions of dibenzothiophene may sterically retard direct hydrogenolysis. Hence, the hydrogenation of the aromatic ring adjacent to the thiophenic ring followed by the hydrogenolysis is a major route for such species. The molecular orbital calculation clarified that the hydrogenation of refractory sulfur compounds with alkyl steric hindrance accelerates their hydrogenolysis by reducing the steric hindrance through molecular puckering and by increasing the electron density on S. The calculation allows us to estimate reactivities of sulfur-containing compounds in both routes and to design the reaction scheme to ensure the most efficient hydrodesulfurization

We fabricated an electrode chip with a structure coated by an insulation layer that contains dispersed SiO2 adsorbent particles modified by an amino-group on a source-drain electrode. Voltage changes caused by chelate molecule adsorption onto electrode surfaces and by specific cation interactions were investigated. The detection of specific cations without the presence of chelate molecules on the free electrode was also examined. By comparing both sets of results the complexation ability of the studied chelate molecules onto the electrode was evaluated. Five pairs of source-drain electrodes (×8 arrays) were fabricated on a glass substrate of 20 × 30 mm in size. The individual Au/Cr (1.0/0.1 μm thickness) electrodes had widths of 50 μm and an inter-electrode interval of 100 μm. The fabricated source-drain electrodes were further coated with an insulation layer comprising a porous SiO2 particle modified amino-group to adsorb the chelate molecules. The electrode chip was equipped with a handy-type sensor signal analyzer that was mounted on an amplifier circuit using a MinishipTM or a system in a packaged LSI device. For electrode surfaces containing different adsorbed chelate molecules an increase in the sensor voltage depended on a combination of host-guest reactions and generally decreased in the following order: 5,10,15,20-tetrakis(N-methylpyridinium-4-yl)-21H,23H-porphine, tetrakis(p-toluenesulfonate) (TMPyP) as a Cu2+ chelator and Cu2+ > 2-nitroso-5-[N-n-propyl-N-(3-sulfopropyl)amino]phenol (nitroso-PSAP) as an Fe2+ chelator and Fe2+ > 4,7-diphenyl-1,10-phenanthrolinedisulfonic acid, disodium salt (BPDSA) as an Fe2+ chelator and Fe2+ > 3-[3-(2,4-dimethylphenylcarbamoyl)-2-hydroxynaphthalene-1-yl-azo]-4-hydroxybenzenesulfonic acid, sodium salt (XB-1) as a Mg2+ chelator and Mg2+ > 2,9-dimethyl-4,7-diphenyl-1,10-phenanthrolinedisulfonic acid, disodium salt (BCIDSA) as a Cu2+ chelator and Cu2+, respectively. In contrast, for the electrode surfaces with adsorbed O,O'-bis(2-aminoethyl)ethyleneglycol-N,N,N',N'-tetraacetic acid (GEDTA) or O,O'-bis(2-aminophenyl)ethyleneglycol-N,N,N',N'-tetraacetic acid, tetrapotassium salt, hydrate (BAPTA) as a Ca2+ chelator no increase in the detection voltage was found for all the electrode tests conducted in the presence of Ca2+. To determine the differences in electrode detection, molecular orbital (MO) calculations of the chelate molecules and surface molecular modeling of the adsorbents were carried out. In accordance with frontier orbital theory, the lowest unoccupied MO (LUMO) of the chelate molecules can accept two lone pair electrons at the highest occupied MO (HOMO) of the amino group on the model surface structure of the SiO2 particle. As a result, a good correlation was obtained between the LUMO-HOMO difference and the ion response of all the electrodes tested. Based on the results obtained, the order of adsorbed chelate molecules on adsorption particles reflects the different metal ion detection abilities of the electrode chips.

NiMo触媒上におけるジベンゾチオフェン, および4,6-ジメチルジベンゾチオフェンのデカリン中での脱硫反応に, ナフタレンおよびテトラリンを共存させた場合の反応性および反応ルートを調べた。4,6-ジメチルジベンゾチオフェンの脱硫ルートは, 硫黄原子が直接脱硫される直接脱硫ルートと, 少なくとも片環が水素化された後に硫黄原子が脱硫される水素化脱硫ルートの二つであり, 後者が主反応である。しかし, 芳香族化合物が共存すると片環および両環水素化が阻害され, 脱硫が著しく低下した。阻害の大きさは, デカリン

ディーゼル軽油中の難脱硫性硫黄化合物である4-メチルジベンゾチオフェン, 4,6-ジメチルジベンゾチオフェンを合成し, デカリン溶媒中での反応性をジベンゾチオフェンと比較した。アルキルジベンゾチオフェンの脱硫反応には分子内の環が水素化されてから硫黄原子が脱硫される反応経路 (水素化脱硫) と, 硫黄原子が直接脱硫される反応経路 (直接脱硫) の二つがあるが, 置換メチル基の数の増加に伴い, 直接脱硫/水素化脱硫の比がジベンゾチオフェン(0.94)>4-メチルジベンゾチオフェン(0.37)>4,6-ジメチルジベンゾチオフェン(0.12) の順で減少した。硫黄原子近傍にメチル基が置換されると, NiMoおよびCoMo触媒のいずれでも環水素化を律速とする水素化脱硫経路の方が優先する。NiMo触媒を用いた場合, 反応温度, 水素圧, 反応時間の増加に伴い環の水素化が促進され, 水素化脱硫ルートが増加した。水素化中間体から硫黄原子が脱離するステップの速度定数は, 水素化脱硫ルートの優先性を反映して, 直接脱硫ステップの速度定数よりも4-メチルジベンゾチオフェンで30～35倍, 4,6-ジメチルジベンゾチオフェンでは約100倍も大きい。また, 直接脱硫ステップの速度定数は, 4,6-ジメチルジベンゾチオフェンでk2=2.02×10-5, 4-メチルジベンゾチオフェンでk10=6.9×10-5に対し, ジベンゾチオフェンではk13=1.82×10-4と前二者と比較して3～9倍も大きい。しかし, 前者の水素化物の脱硫反応速度は後者の直接脱硫反応速度より速いことから, 環の水素化によりメチル基の立体障害の解消, およびC-S結合の活性化が推定できる。このようにアルキルジベンゾチオフェンの脱硫反応は, メチル基の立体障害のため直接脱硫反応性に乏しく, また環の水素化を律速段階としているため, 脱硫反応条件下で水素化活性の高いNiMoがCoMoより高い活性を示すことが理解できる。

Recently, bio-microelectromechanical systems (Bio MEMSs) composed of a micro pump, mixer, valve, reactor, sensor, and an electric circuit on a chip, have being applied to biological or medical analyses. A microsensor mounted on a chip has been developed to measure the concentration of a one drop solution. The form of the microsensor on a chip was thin Cu electrodes of 12 mm2. The sensing function was evaluated by the concentration measurement of a solution (100nL) dropped on the microsensor, which could analyze electrolytes and amino acids. The electric resistance of the microsensor related well to the concentration of the solution. Further, the electric resistance of the sensor was related to light intensity that was irradiated to its surface. To measure the concentration of a solution, it is necessary to irradiate light of a constant intensity on the microsensor.