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In this paper, we propose several types of planar micro-electromagnetic actuator that can be applied in micro-pumps and micro-valves. The various types each consist of a thin film permanent magnet (TFPM), a micro-coil and, in some cases, a ferromagnetic layer. The magnetic properties of a TFPM with a multilayered structure, comprising 300 nm thick NdFeB and 10 nm thick Ta layers deposited sequentially, are as high as bulk NdFeB magnets. Conventional micro-electromagnetic actuators consist of a bulk permanent magnet and a spiral micro-coil, whereas the actuators proposed in this paper consist of segmented patterns of TFPM, such as line/space and chessboard patterns, and mesh coils surrounding the segmented patterns. The TFPMs are segmented in order to reduce the demagnetization effect and to generate a large flux density. The proposed micro-coils possess a 2D structure and are easy to fabricate compared with spiral type micro-coils. The results of simulation show that the electromagnetic forces generated by actuators with segmented TFPMs are several times higher than one without segmentation. Furthermore, the actuation force performance is enhanced by covering the TFPM pattern with a ferromagnetic layer of Ni55Fe45 permalloy. The electromagnetic actuators are fabricated by a fully integrated MEMS process. The measured magnetic flux densities generated by the patterned TFPMs agree with the simulated results. The electromagnetic force between the patterned TFPM and the micro-coil is measured by an electronic force balance. Due to alignment errors between the micro-magnet and micro-coil, the experimentally measured forces are from 70% to 90% of the simulated ones.

The effect of the annealing temperature on the magnetostrictive properties of Fe­Co alloy thin films on quartz glass was systematically investigated. The saturation magnetostriction was 56ppm for the Fe32Co68-sputtered thin film quenched from 673K, and it increased to 159ppm with increasing annealing temperature up to 1073K. The magnetostriction above 1093K significantly decreased with the emerging fcc phase in the Fe­Co alloy. SEM images showed that the crystal grains present in the fcc phase aggregated to form a discontinuous surface, which resulted in a decrease in the effective magnetostriction. Measurements of the magnetic properties by vibrating sample magnetometer and magnetic force microscopy revealed the enhancement of the magnetization at the crystal grain boundaries of Fe­Co alloy thin films with large magnetostriction. Thus, the heterogeneity of the magnetization can play a key role in inducing the large magnetostrictive effect. [doi:10.2320/matertrans.MBW201315]

Schizophrenia is a disease that affects many areas of the brain. The dopamine hypothesis is one of the most widely-accepted ideas in the pathophysiology of schizophrenia. Besides alterations in the dopaminergic system in the central nervous system, there have been several reports of changes in dopaminergic systems in the peripheral blood of schizophrenic patients. Several reports have shown that dopamine receptor expression by lymphocytes is altered in patients with schizophrenia, but the results have been conflicting. We therefore re-assessed D3R and D4R mRNA levels in 11 patients with schizophrenia and 12 healthy subjects and correlated levels with severity of symptoms. D3R and D4R expression in lymphocytes and granulocytes was measured by quantitative RT-PCR and the severity of symptoms and cognitive impairment were assessed using the PANSS and BACS-J. There were no significant differences in mean D3R or D4R mRNA levels in lymphocytes from schizophrenic patients and controls and no significant difference in mean D4R mRNA levels in granulocytes (D3R mRNA undetectable). In patients with schizophrenia, D3R expression was inversely correlated with the total PANSS score (r = 0.768, p = 0.009), while D4R expression was positively correlated with working memory scales (r = 0.895, p = 0.001). In conclusion, these results imply that lymphocyte D3R and D4R are involved in the mechanisms of the disorder and could be used as target markers in the treatment of schizophrenia.

Nuclear waste contains a significant amount of long-lived non-gamma-emitting nuclei such as 129 I and 14 C. A method of nondestructive detection for monitoring long-lived waste products is proposed as an application of the (y, n) reaction. This method is useful for surveying long-lived "difficult-to-measure" nuclides, e.g., 129 I. Iodine-128 produced from the reaction of 129 I(γ, n) 128 I emits gamma rays that can easily be measured by a gamma-ray counter. We measured the inclusive photonuclear 129 I(γ, n) 128 I reaction cross section induced by bremsstrahlung photons. The photons were produced at a Ta target bombarded by 30-MeV electrons from a linear accelerator. The intensity of the slow neutrons was considered in the reactions of 127 I(n, γ) 128 I and 129 I(n, γ) 13 °1. The activity of 128 I was measured by a high-purity germanium spectrometer. The gamma-ray flux and the neutron flux were calculated using the EGS and MCNP codes, respectively. The average activation cross section of the 129 I(γ, n ) 128 I reaction had a 12% deviation from the evaluated International Atomic Energy Agency photonuclear data.

Many long-lived non-gamma emitting radioactive nuclei such as 129I, 14C and 93Zr are produced as wastes from nuclear fuel cycle facilities. They are called “difficult-to-measure” radio nuclei. Among them 129I is a long-lived β-emitting isotope with a half-life of 1.57 × 107 years. Iodine compounds are mobile in the vadose zone and groundwater and increase a significant long-term risk. Transmutation of 129I is a challenging issue in nuclear waste management and disposal. If 129I is transmuted into 128I (half life; 25 minutes), it can easily be measured by a Ge detector. However, the 129I(γ, n) reaction cross section has not been measured so far. In this study we have measured the inclusive 129I(y, n)128I cross section by using bremsstrahlung photons. The bremsstrahlung photons were produced from a 30-MeV electron linac. Measured average activation cross section agrees with 12% deviation from the evaluated one in the IAEA photonuclear data library. Gamma and neutron fluxes for the (γ, n) and the (n, γ) reac...

Semi-dry flue gas desulfurization was investigated with several kinds of SO 2 sorbents, such as slaked lime, limestone, Mg(OH) 2 and concrete pile sludge, in a powder-particle spouted bed. Slurry droplets including sorbent fine particles were fed to a spouted bed of coarse inert particles spouted with hot gas containing SO 2 . SO 2 removal efficiency was strongly affected by the approach to saturation temperature, Ca/S molar ratio and particle size of sorbent. Slaked lime showed the highest desulfurization efficiency. In this process, despite very short gas residence time, more than 90% SO 2 removal was easily achieved by choosing appropriate conditions.

The effects of particle size and weight fraction of fine powder (group C) upon the entrainment rate of bed particles (groups B + C or groups A + C) and fine powder were investigated in a fluidized bed and in a circulating fluidized bed. The entrainment rates and elutriation rate constants of the bed particles and fine powder were strongly affected by the particle size and the weight fraction of fine powder in the bed. A clear difference was observed in the dependence on the weight fraction of fine powder in both the entrainment rate of bed particles and the ratio of the elutriation rate constant of fine powder to that of coarse particles between the B–C and A–C binary particle systems. When fine powder of 6 μm or smaller was added, the elutriation rate constant of fine powder decreased as the mean diameter of the bed particles decreased from 40 μm. On the other hand, addition of group C powder of larger than 10 μm to group A particles showed very good fluidization with the large entrainment rate of the bed particles.

Research on the merits of long-term group residences is inconclusive. The purpose of the present paper was to investigate the effects of supported group residence on the symptoms, social function, quality of life, general health quality, and the medical/psychiatric cost in Japan of a large number of psychiatric beds and long average length of stay. Patients were assessed every 6 months for 2 years using Positive and Negative Syndrome Scale, Katz Adjustment Scale, World Health Organization Quality of Life (WHO-QOL) and General Health Questionnaire 12-item version. Patients discharged to the supported group residence (SGR) significantly improved with regard to positive symptoms, the level of socially expected activities and free-time activities. The QOL physical domain of the inpatients was significantly more deteriorated compared to the SGR group. The total psychiatric/medical cost of the SGR group was approximately one-third that of the inpatient group, while the cost of the SGR to treat physical comorbidity was much higher. The present findings indicate that SGR has advantages for mental and social function but not for physical health. A major limitation of the present study was the high mean age (>60 years) of the subjects who had been hospitalized for a long period (mean, 24 years).

Post-traumatic stress disorder (PTSD) is a stress-related mental disorder caused by traumatic experience, and presents with characteristic symptoms, such as intrusive memories, a state of hyperarousal, and avoidance, that endure for years. Single-prolonged stress (SPS) is one of the animal models proposed for PTSD. Rats exposed to SPS showed enhanced inhibition of the hypothalamo-pituitary-adrenal (HPA) axis, which has been reliably reproduced in patients with PTSD, and increased expression of glucocorticoid receptor (GR) in the hippocampus. In this study, we characterized further neuroendocrinologic, behavioral and electrophysiological alterations in SPS rats. Plasma corticosterone recovered from an initial increase within a week, and gross histological changes and neuronal cell death were not observed in the hippocampus of the SPS rats. Behavioral analyses revealed that the SPS rats presented enhanced acoustic startle and impaired spatial memory that paralleled the deficits in hippocampal long-term potentiation (LTP) and depression. Contextual fear memory was enhanced in the rats 1 week after SPS exposure, whereas LTP in the amygdala was blunted. Interestingly, blockade of GR activation by administering 17-beta-hydroxy-11-beta-/4-/[methyl]-[1-methylethyl]aminophenyl/-17-alpha-[prop-1-ynyl]estra-4-9-diene-3-one (RU40555), a GR antagonist, prior to SPS exposure prevented potentiation of fear conditioning and impairment of LTP in the CA1 region. Altogether, SPS caused a number of behavioral changes similar to those described in PTSD, which marks SPS as a putative PTSD model. The preventive effects of a GR antagonist suggested that GR activation might play a critical role in producing the altered behavior and neuronal function of SPS rats.

We developed thin-film magnetic field probes with a high spatial resolution aiming to obtain the absolute value of a high-frequency power current on an LSI chip. The spatial resolution was enhanced by miniaturizing the shielded loop coil, which is the detection part of the probe. The minimum outer size of the new coil is 50 x 22 μm. In taking measurements with the new probe over a 60-μm-wide microstrip line used as a device under test (DUT), we found that the probe output decreases by 6 dB at a distance of 40 μm. This value is less than half that of our previous probe, which was around 100 μm. In taking measurements with the new probe over 5-μm-wide microstrip lines used as a DUT, we found that the new probe achieved 10-μm-class high spatial resolution. This value is comparable to the typical width of global power lines on an LSI chip, which ranges from 10 μm to 100 μm. We estimated the configuration of the lines on an LSI chip that would enable the new probe to achieve a spatial resolution high enough to obtain the absolute value of a high-frequency power current on an LSI chip.

The penetration of fine cohesive powders through a powder-particle fluidized bed (PPFB) was studied and correlated with the hold-up of fine powders in the bed. Silica sand, limestone, glass beads, bentonite, composite clay and silica gel of 550 μm mean size and silica sand of 780 μm mean size were used as coarse particles. Aluminum hydroxide powders of 0.5, 1.0 and 3.0 μm mean size were used as fine powders. The effects of aerosol concentration and size of fine powders, type of coarse particles and superficial gas velocity on the penetrating fraction of fine powders were investigated under various hold-ups of fine powders in the bed at the non-equilibrium state. In the early stage of penetration, the penetrating fraction of fine powders was hardly affected by the inlet aerosol concentration of fine powders, superficial gas velocity and size of coarse particles, but strongly affected by the size of fine powders and type of coarse particles. A fluidized bed of angular coarse particles having a rough surface or a highly rough surface with a granular structure demonstrated very low penetration of aerosol fine powders until relatively high hold-up of fine powders in the bed. Beds of coarse particles having a higher angle of repose gave higher equilibrium hold-up of fine powders in the bed.

Fine powders (Geldart's group C) are added to a circulating fluidized bed (CFB) of coarse particles (Geldart's group A) and the solid circulation rate (SCR) is investigated with addition of fine powders of different sizes and different fractions (different hold-ups) to the bed. Experiments were carried out in a CFB of 2 m in height and 0.052 m in diameter, using FCC catalyst particles of 66 μ m as the coarse particles and cohesive aluminum hydroxide powders of 0.5– 15 μ m as the fine powders. The effects of hold-up of fine powders in the bed, fine powders size, and superficial gas velocity on the SCR were investigated. The SCR strongly depended on the hold-up of fine powders of 0.5 – 1.0 μ m in size and noticeably decreased with increasing the hold-up of fine powders under constant gas velocity. This dependency disappeared when the size of fine powders was larger than 3.0 μ m . Thus, depending on the size of fine powders added to the CFB, two distinct regions for the changes of SCR could be clearly identified.

Circulating fluidizing system of binary Geldart C powders and Geldart A particles was formed, and was called a circulating powder-particle fluidized bed (CPPFB). Solid residence in the CPPFB was concerned in two aspects, namely, bed turnover time and average turnover time of fine powders. The former represented the average time needed for all the bed particles to be circulated, while the latter represented the time needed for all the fine powders in the bed to be discharged out of the bed. Both parameters were investigated under different operating conditions as to the superficial gas velocity, size and hold-up of fine powders. FCC particles of 66 μm were used as coarse particles and 1–5 wt.% Al(OH) 3 powders of different sizes ranging from 0.5 to 15 μm were used as fine powders. The bed turnover time decreased with increasing the size of fine powders to a certain level and then became almost constant with further increase of the size of fine powders. When the size of fine powders was larger than this critical size, neither the size nor the hold-up of fine powders affected the bed turnover time. The bed turnover time drastically increased with increasing the hold-up of fine powders for the cases of using very fine powders of 1.0 μm or smaller. On the other hand, the average turnover time of fine powders decreased with increasing the size of fine powders to a minimum at around 3.5 μm and then increased with increasing the size of fine powders. It also decreased with increasing the gas velocity and decreasing the hold-up of fine powders in the bed. The average turnover time of fine powders was several times larger than the bed turnover time at the same operating conditions.

In this study, group C powder in Geldart's classification was added to a circulating fluidized bed or a fluid bed of group A particles. We define this system as a circulating powder-particle fluidized bed (CPPFB). The separation rate of fine powders from a CPPFB was investigated using two different types of solid collectors. A cyclone or a settling chamber was used as a solid collector. The effects of the superficial gas velocity (0.65–1.0 m/s), the holdup of fine powders in the bed (0–5 wt.%), and the size of fine powders (0.5–15 μm) on the separation rate of fine powders from the system were investigated. The separation rate increased with the increases in the holdup of fine powders in the bed and the superficial gas velocity. Irrespective of the type of the solid collector, the separation rate of fines was strongly influenced by the fine powder size and reached the maximum at a fine powder size around 3.5 μm. However, operation with a settling chamber causes a threshold of holdup of fine powders in the bed, below which the separation of fine powders did not occur. An empirical equation for the separation rates of fine powders of 0.5–3.0 μm in size from the CPPFB was obtained.

The elutriation of fine particles (Group C or A particles in Geldart's classification) from a fluid bed of mixed fine and coarse particles is investigated in a steady state. Al(OH) 3 and alumina and TiO 2 powder of 0.5– 32 μm were used as fines. FCC, alumina, Al(OH) 3 , limestone, silica sand, SiC particles of 44– 97 μm were used as coarse particles. The paper investigates the effect on the elutriation rate constant of both fine powders and coarse particles (i) of the weight fraction of Geldart C powders in the bed, (ii) of the superficial gas velocity, and (iii) of the size of C powder and size of coarse particles in the bed. The elutriation rate constant of group C or group A particles is not only affected by the properties of the elutriated powders or particles and gas velocity, but also by both the weight fraction and size of C powder in the bed. This finding differs from the elutriation result of A or B particles from a fluidized bed.

An efficient dry desulfurization process for hot coal gas was proposed. The process uses a powder-particle fluidized bed as the reactor, in which coarse particles of several hundred micrometers are fluidized via hot gas consisting of H2S, H2, and N2 while fine limestone particles are fed continuously into the bed. Fine limestone particles of less than 30 μm were used as H2S sorbent. The effects of operating parameters on the H2S removal efficiency were investigated. Desulfurization via 5-μm limestone was very effective, demonstrating over 90% H2S removal at 1073 K for the case of Ca/S = 2, even under the conditions of a very short residence time (0.3 s) of gas in the bed. Investigation of the sorbent pore structure before and after calcination and desulfurization revealed the correspondence of higher specific surface area of CaO to higher H2S removal efficiency.

The hydrodynamic behavior of a circulating powder-particle fluidized bed (CPPFB) was examined in terms of total solid entrainment rate and fine particle hold-up. Experiments were carried out in a circulating fluidized bed of 2 m in height and 0.052 m in diameter, using FCC catalyst particles of 66 μm as the coarse particles and cohesive aluminum hydroxide powders of 0.5 μm, 1 μm and 3 μm as the fine particles. The effects of adding cohesive fine particles on the total solid entrainment rate were investigated under different operating gas velocities. The total solid entrainment rate at the same operating gas velocity was found to increase with the increase in the fine particle size and decrease with the increase in fine particle hold-up.

The delta2 glutamate receptor (GluRdelta2) is predominantly expressed in the postsynaptic densities of parallel fiber-Purkinje cell synapses and plays a crucial role in cerebellar function. However, the mechanisms by which GluRdelta2 participates in cerebellar functions are largely unknown because GluRdelta2 does not bind glutamate analogs. We investigated the possibility that GluRdelta2 may be involved in channel formation together with other glutamate receptor families. We transiently expressed lurcher mutant AMPA receptor GluR1(Lc) and kainate receptor GluR6(Lc) in HEK293 cells. Cells expressing these constitutively active channels displayed a rectifying current-voltage (I-V) relationship. However, when cells were co-transfected with GluRdelta2(Lc), which had the arginine residue in the channel pore region, cells displayed a linear I-V relationship, a result that indicates GluRdelta2(Lc) formed functional heteromeric channels with GluR1(Lc) or GluR6(Lc). Assembly of GluRdelta2 with GluR1 or GluR6 was further confirmed by co-immunoprecipitation assays in HEK293 cells. In addition, GluRdelta2 receptors were partially co-immunoprecipitated from cerebellar synaptosomal fractions by antibodies against GluR2 or KA2. In contrast to lurcher channels, expression of wild-type GluRdelta2 significantly reduced the glutamate-induced current of the wild-type GluR1 receptors without affecting channel properties, such as current kinetics, dose-response relationship, and single-channel conductance. Thus, the heteromeric channel created by the association of wild-type GluR1 and GluRdelta2 may not be gated by glutamate and does not participate in glutamate-induced currents. These results suggest that GluRdelta2 and AMPA or kainate receptors can assemble to form heteromeric receptors in vitro and could modify glutamate signaling in vivo. These findings may help explain the role of GluRdelta2.

Electrophysiological studies have shown that decreases in extracellular Ca 2+ concentration and increases in extracellular K + concentration cause non-synaptic seizure-like neuronal activity in the hippocampus. Using the calcium imaging technique, we investigated the role of intracellular Ca 2+ concentration in the cause of non-synaptic seizure-like neuronal activity. Rat hippocampal slice culture was loaded with calcium indicator dye. Non-synaptic seizure-like neuronal activity was induced by low Ca 2+ /high K + solution. The calcium imaging, with a confocal laser scanning microscope and extracellular field recording were made simultaneously. Pharmacological inhibitors were used to examine the mechanism of the intracellular Ca 2+ changes. As a result, intracellular Ca 2+ oscillation occurred in neurons in a nonuniform fashion after replacing the solution, and then, gradual massive synchronization occurred in the large population. This massive synchronized Ca 2+ oscillation propagated transversely through the CA1 area at a velocity of 4.2–6.8 mm/min. A negative shift, which reflects seizure-like neuronal activity, was observed in extracellular field recording, corresponding to the synchronized intracellular Ca 2+ oscillation. Voltage-dependent calcium channel blocker and gap junction blocker inhibited this synchronization and the propagation. In conclusion, using the calcium-imaging technique, we demonstrated dynamic changes in synchronization and propagation of intracellular Ca 2+ oscillation, which corresponded to non-synaptic epileptiform activity. The role of gap junction as a contributing mechanism was speculated.

The influence of imipramine and lithium on the expression of calcineurin (CaN) and its serine/threonine phosphatase activity in the rat frontal cortex and hippocampus was examined. Northern blot analysis demonstrated that single or repeated (14 day) administration of imipramine did not affect the levels of CaN A (catalytic subunit) mRNA in rat brain. Similarly, the administration of lithium for 1 or 14 days had no effect on the expression of CaN A mRNA. In contrast, the acute administration of imipramine significantly increased CaN activity in the cortex and hippocampus. In addition, the chronic (14 day) administration also significantly increased CaN activity. However, administration of lithium for either 1 or 14 days did not influence CaN activity. These findings indicate that imipramine, but not lithium, increases the phosphatase activity of CaN, suggesting that the changes in neuronal functions induced by CaN may be involved in the molecular activity of imipramine.

静止状態から流動化状態に遷移する際の層の電気導電率と層膨張の関係を，66μm～490μmのカーボン粒子およびその一部に17μmの微粒子カーボンを添加した二成分系を用いて測定し，導電率に及ぼすガス速度の影響，粒子径の影響，微粒子添加の影響を調べた．層の電気抵抗はガス速度の増加に対しS字型を示し，最小流動化速度付近で急激な増加が見られた．単成分系では粒子径によらず導電率の大きさはおおよそ同程度であったが，微粒子を添加した二成分系ではおおよそ1桁高くなることがわかった．また，粒子体積率比と導電率比の関係曲線として，それぞれの空隙生成状況を特徴づけた．

A new semi-dry process to produce very fine calcium carbonate powder is developed. Ca(OH)2 slurry droplets are continuously fed into a spouted bed of coarse medium particles, and react with CO2 in fluidizing gas to produce fine CaCO3 powder. The CaCO3 powder is dried with fluidizing gas, and fine CaCO3 powder is entrained from the bed to be collected with a bag filter. The effect of operating conditions, such as the concentration of the Ca(OH)2 slurry, CO2 concentration in the fluidizing gas, approach to saturation temperature, superficial gas velocity and static bed height, on the conversion of Ca(OH)2 to CaCO3 and the particle size of product CaCO3 powder are investigated.Very fine CaCO3 powder and high Ca(OH)2 conversion are obtained in the case of low concentration of Ca(OH)2 in the feed slurry and high concentration of CO2 in the fluidizing gas. This method can produce very fine calcium carbonate powders with the mean particle size around 1 μm and the Ca(OH)2 conversion around 90%.

The minimum fluidization velocity was measured for various binary particle mixtures of coarse particles of group A or B and fine particles including group C particles of Geldart classification in the range where the weight fraction of the fine particles was less than 15 wt%. The minimum fluidization velocity decreased with the increase in the fraction of the fine particles in all cases; especially in the systems with group C particles, a remarkable decrease in the minimum fluidization velocity was observed with the increase in the fine particle fraction. Such a decrease in the minimum fluidization velocity observed in the systems with group C particles was expressed by the formation of aggregated particles consisted of the coarse and the fine particles. Mixing/segregation appearance of the system was also observed, revealing that group C particles can be fluidized and mixed homogeneously with coarse particles in a certain rage of the fine particle fraction. The range of the fine particle fraction for homogeneous mixing was dependent on the systems.

Intracellular calcium release in response to bath-applied quisqualate or caffeine was examined in cerebellar primary cultures of type-1-inositol-1,4,5-trisphosphate-receptor (IP3R1)- deficient mice. Under [Ca2+]o-free conditions, calcium release in response to 10 microM quisqualate was significantly reduced in Purkinje cells, but was unaffected in granule cells, suggesting that different subtypes of IP3 receptors contribute to the metabotropic glutamate response in these cells. In addition, calcium release in response to 10 mM caffeine under [Ca2+]o-free conditions was not impaired in cerebellar cells, suggesting that IICR and CICR are independently regulated in cerebellar cells. Moreover, in both wild-type and homozygous mutant mice, CICR in granule cells was approximately 6 times greater than in Purkinje cells.

Using gas-solid flows in circulating fluidized-bed risers to analogize vertical pneumatic conveying systems, the collapse of dilute suspension, that is, the choking of accumulative type, was studied in three different risers with respect to different particles. The collapse of dilute suspension was dominated by an identical differential pressure drop over the measuring section. This differential pressure drop was independent of gas velocity and riser diameter, but varied with particle properties. The saturation carrying capacity, the solid flow rate at the dilute suspension collapse, was closely related to particle characteristics and riser diameter. With an increase in the riser diameter, it increased for lighter and smaller particles, but decreased for heavier and larger particles. Based on these experimental measurements, as well as the related literature reports, a correlation was developed for the saturation carrying capacity by analyzing its dependencies on gas velocity and riser diameter. More than 150 experimental data of the saturation carrying capacity available in the literature were compiled to evaluate the accuracy of the proposed correlation by comparing with 13 other literature correlations, demonstrating that this new method has the highest accuracy.

The elutriation of fine particles (groups C or A particles) from a fluidized bed of fine–coarse particle mixtures was investigated at steady state. FCC and alumina particles were used as fines, Alumina, FCC, PVC, SiC and silica sand particles (groups A or B particles) were used as coarse particles, respectively. The elutriation rate constant of group C particles (adhesion particles) decreased with increases in the mean diameter of bed particles and with decreases in the size of elutriated particles under the condition of a constant superficial gas velocity. This finding is quite different from that of elutriation of groups A or B particles. The elutriation rate constant of group C particles was hardly affected by the density of coarse particles in the bed. To correlate the elutriation rate constant for adhesion particles, the particle size coefficient (Cps) is introduced. Empirical equations of elutriation rate constant for cohesive particles were obtained. The proposed correlation well predicts the values of elutriation rate constant of cohesive particles.

In the present study, we used inositol-1,4,5-trisphosphate (IP3) type 1 receptor (IP3R1) knockout mice to examine the role of this receptor in the induction of LTP, LTD, and DP at mossy fiber-CA3 synapses. No difference in synaptically induced field-EPSPs was seen between the wild-type (IP3R1(+/+)) and IP3R1 knockout mice (IP3R1(-/-)), showing that basic synaptic transmission does not involve IP3R1 activation. Tetanus induced LTP in both wild-type and IP(3)R1(-/-) mice, but the magnitude of LTP was significantly greater in IP3R1(-/-) mice (149.8+/-3.5%, mean+/-S.E.M., n=15) than in wild-type mice (132.4+/-1.5%, n=17), suggesting that the IP3R1 has a suppressive effect on LTP induction. To determine whether this effect involved N-methyl-D-aspartate receptor (NMDAR)-dependent LTP, the effect of tetanus was tested in the present of the NMDAR antagonist, D,L-AP5 (50 microM); under these conditions, the LTP in both IP3R1(-/-) and IP3R1(+/+) mice was not significantly reduced. In addition, group I mGluR activation was shown to be necessary for LTP induction, as the LTP was almost blocked by the group I mGluR antagonist, RS-4CPG (500 microM) in both IP3R1(-/-) (117.6+/-1.7%, n=8) and IP3R1(+/+) (116.9+/-1.8%, n=5) mice. The IP3R1 also plays an essential role in LTD induction, as low-frequency stimulation (LFS) failed to induce LTD in the mutant mice (104.5+/-2.1%, n=10). DP was induced in both IP3R1(-/-) and wild-type mice.

Short-term plasticity, the effect of a preceding synaptic response on the following response in a pair, in layers II/III of the rat auditory cortex slice after application of repetitive stimuli to layer IV, was investigated using a multichannel extracellular recording system. Paired-pulse depression, which is induced to a moderate degree in standard artificial cerebrospinal fluid, was markedly facilitated in the presence of bicuculline, a GABA(A) receptor antagonist, concurrent with the emergence of a polysynaptic component of the EPSP (polyEPSP) in the first response in a pair. This depression (bicuculline-facilitated synaptic depression, BFSD) was maximal at the minimum interval tested (50 ms), reduced as the interval was increased, and persisted beyond an interval of 2 s. The occurrence of BFSD was dependent on the presence of a polyEPSP regardless of the presence of the monosynaptic component of the EPSP, indicating that BFSD is induced by a heterosynaptic mechanism. D-AP5, an NMDA receptor antagonist, partially eliminated polyEPSPs and reversed BFSD. These results suggest that activation of polysynaptic excitatory pathways induces a heterosynaptic depression in the range of a few seconds and that NMDA receptor activity is involved in this heterosynaptic depression.

A novel sorbent, potassium carbonate impregnated on porous fine alumina, was produced, and its reactive and regenerative properties were evaluated for dry-type simultaneous removal of SO2 and NO from flue gas under stack temperatures, by using a powder-particle fluidized bed (PPFB) with I.D. of 53 mm as the reactor. High removal efficiencies for SO2 and NO were achieved simultaneously. An apparent beneficial effect of SO2 on the enhancement of NO removal was found based on a large amount of data. The alumina carrier was successfully regenerated and used repeatedly for the production of fresh sorbent particles. With no ammonia, low temperature, high removal efficiency, and no second waste emission as main characteristics, this dry process can be a competitive technology for pollution control of flue gas from power plants in the future.

The elutriation of fine particles (group C or A particles) from a fluidized bed of fine-coarse particle mixtures was investigated in a steady state. Alumina particles were used as fine; PVC, alumina, SiC and silica sand particles (group A or B particles) were used as coarse particles. The effect of the relative humidity on the elutriation rate constant was investigated for different elutriated particle sizes and bed particles. There were three different zones between the elutriation rate constant and the relative humidity. At the lower relative humidity, the elutriation rate constant increased with increasing relative humidity. When the relative humidity reached a certain value, the elutriation rate constant was not affected by the relative humidity. We defined this relative humidity as the electrostatic relative humidity (RHe). In the middle relative humidity region, the elutriation rate constant was not affected by the relative humidity. When the relative humidity increased and reached a certain higher value, the elutriation rate constant decreased with an increase of relative humidity. We defined this relative humidity as the capillary relative humidity (RHc). When the relative humidity is smaller than RHe, the elutriation rate constant is affected by the electrostatic forces of the bed particles and the elutriation rate constant increased with an increase of relative humidity. When the relative humidity is higher than RHc, the elutriation rate constant is affected by the capillary forces of the bed particles and the elutriation rate constant decreased with an increase of relative humidity.

As one of the key technologies in the development of a direct internal-reforming solid oxide fuel cell, catalytic activity and stability of a Ni–YSZ–CeO2 anode on a zirconia electrolyte for the steam reforming of methane was investigated by experiments using a differential fuel cell reactor. The effects of the partial pressure of CH4, H2O and H2, and temperature as well as the electrochemical oxidation on the catalytic activity were analyzed. It was found that the catalytic activity of the Ni–YSZ–CeO2 anode was higher than that of the Ni–YSZ reported especially at low temperature. A deterioration of the catalytic activity of the anode was observed at low PH2 and high PH2O atmosphere, and also at high current densities. This might be caused by the oxidation of the Ni surface by H2O in the reaction gas and that produced by the anodic reaction. A rate equation for a fractional function for the steam reforming on open circuit was also proposed.

The elutriation of fine particles (group C or group A particles) from a fluidized bed of fine-coarse particle mixtures was investigated at a steady state. FCC, AL(OH)3, limestone, alumina, SiC, PVC and silica sand particles in the range of 22.44 to 650 μm were used as the fluidized particles. The elutriation rate constant of particles increased with increase of particle size in the range of group C particles at the constant superficial gas velocity and decreased with increase of the particle size in the rage of group A and B particles. The particle size corresponding to the maximum elutriation rate constant is defined as the critical particle size of the elutriation. The critical particle size decreases with increasing elutriated particle density and with increasing gas velocity. On the contrary, the critical particle size increases with increasing the mean diameter of bed particles. But, the coarse particle density has no effect on the critical particle size. An empirical equation is obtained to estimate the critical particle size.

Activity-induced synaptic modification is essential for the development and plasticity of the nervous system. Repetitive correlated activation of pre- and postsynaptic neurons can induce persistent enhancement or decrement of synaptic efficacy, commonly referred to as long-term potentiation or depression (LTP or LTD). An important unresolved issue is whether and to what extent LTP and LTD are restricted to the activated synapses. Here we show that, in the CA1 region of the hippocampus, reduction of postsynaptic calcium influx by partial blockade of NMDA (N-methyl-D-aspartate) receptors results in a conversion of LTP to LTD and a loss of input specificity normally associated with LTP, with LTD appearing at heterosynaptic inputs. The induction of LTD at homo- and heterosynaptic sites requires functional ryanodine receptors and inositol triphosphate (InsP3) receptors, respectively. Functional blockade or genetic deletion of type 1 InsP3 receptors led to a conversion of LTD to LTP and elimination of heterosynaptic LTD, whereas blocking ryanodine receptors eliminated only homosynaptic LTD. Thus, postsynaptic Ca2+, deriving from Ca2+ influx and differential release of Ca2+ from internal stores through ryanodine and InsP3 receptors, regulates both the polarity and input specificity of activity-induced synaptic modification.

With two different kinds of particles and three different circulating fluidized (CFB) bed risers, the riser diameter influences on bed density for different particles were investigated by measuring the total pressure drop across the whole riser and the axial profile of apparent voidage. The risers had the same bed height of 3.0 m but different inner diameters of 66, 97 and 150 mm, respectively. Particles of FCC and silica sand were used, which belong to types A and B of Geldart classification, respectively. It was found that riser diameter has opposite influences for Geldart A and B particles on the total pressure drop across the whole riser and the differential pressure gradient (apparent solids concentration) at a specified bed elevation. With increasing riser diameter, these two pressure drops increase for group B but decrease for group A particles, consistent with several other literature measurements in pilot-scale risers. As a result of these different dependencies of bed density on riser diameter, the saturation-carrying capacity, i.e., the solids circulation rate at the dilute suspension collapse, was also found to vary differently with riser diameter for different particles. That is, the increase in riser diameter increases the saturation-carrying capacity for Geldart A but decreases it for Geldart B particles.

Hydrated lime is normally used as SO 2 sorbent in spray dry scrubbers, whereas limestone is considered unreactive under conditions prevailing in such a system. However, limestone is more easily available and several times cheaper than hydrated lime. We tried to use limestone to remove SO 2 from flue gas in the semidry FGD process with a powder-particle spouted bed. If limestone can be utilized in the process it would be of particular advantage. In the present study, the effects of operating parameters on SO 2 removal were investigated, such as Ca/S molar ratio, particle size of SO 2 sorbent, apparent residence time of gas in the bed and approach to saturation temperature. The comparison of reactivity with SO 2 between limestone and hydrated lime was also made based on their structural properties. The experimental results showed that SO 2 removal efficiency of limestone was considerably enhanced in the present process by increasing Ca/S molar ratio and decreasing the approach to saturation temperature and sorbent size. Thus, the present process with limestone as SO 2 sorbent may be an attractive alternative to other FGD technologies in terms of removal efficiency, price and availability of sorbent.

Protein tyrosine phosphatase delta (PTPdelta) is a receptor-type PTP expressed in the specialized regions of the brain including the hippocampal CA2 and CA3, B lymphocytes and thymic medulla. To elucidate the physiological roles of PTPdelta, PTPdelta-deficient mice were produced by gene targeting. It was found that PTPdelta-deficient mice were semi-lethal due to insufficient food intake. They also exhibited learning impairment in the Morris water maze, reinforced T-maze and radial arm maze tasks. Interestingly, although the histology of the hippocampus appeared normal, the magnitudes of long-term potentiation (LTP) induced at hippocampal CA1 and CA3 synapses were significantly enhanced in PTPdelta-deficient mice, with augmented paired-pulse facilitation in the CA1 region. Thus, it was shown that PTPdelta plays important roles in regulating hippocampal LTP and learning processes, and that hippocampal LTP does not necessarily positively correlate with spatial learning ability. To our knowledge, this is the first report of a specific PTP involved in the regulation of synaptic plasticity or in the processes regulating learning and memory.

A new semi-dry desulfurization process was tested in this study. The process uses the so-called powder-particle spouted bed (PPSB) as the reactor in which coarse medium particles, usually silica sand of several hundred micrometers in size, are fluidized with hot flue gas. A slurry of fine SO x sorbent, such as slaked lime or other alkaline powder, is continuously supplied into the bed of coarse particles. As a consequence, both the desulfurization reaction and slurry drying take place simultaneously in the single reactor. By using a model flue gas, SO 2 –air, and the sorbent Ca(OH) 2 in a laboratory-scale reactor, the removal efficiency of this process was examined with respect to major operating parameters in this study. It was demonstrated that SO 2 removal in excess of 95% can be achieved at Ca/S=1.2, while spent sorbent appears in the form of dry powder. The optimal temperature of flue gas treated with this technique was shown to be approximately 420 K. In comparison with wet desulfurization scrubbers, this PPSB semi-dry process appears to have lower cost, less complicated configuration and simpler disposal of used sorbent.

This study is devoted to examining an adaptive sorbent for the combined desulfurization/denitration (DeSOx/DeNOx) process reported in work by Xu et al. (Trans. Inst. Chem. Eng. 1999, 77, Part B, 77−87). The so-called powder-particle fluidized bed (PPFB) is used by the process so that SOx in flue gas is absorbed by a continuously supplied fine DeSOx sorbent and NOx is reduced to N2 by ammonia under the catalysis of a coarse DeNOx catalyst, the fluidization medium particles (FMP). Experiments were conducted in a laboratory-scale PPFB reactor by using model flue gases containing SO2 and NO. It was found that the sodium carbonate supported by fine alumina particles (Na2CO3/Al2O3) had not only a high efficiency in absorbing SO2 but also little negative effect upon the simultaneous NOx reduction of the process. Using a DeNOx catalyst, such as V2O5·WO3/TiO2 or WO3/TiO2, to catalyze the DeNOx reactions, high SO2 absorption and NO reduction in excess of 95% were achieved for model gases free of CO2 at stoichiometr...

Inducing long-term depression (LTD), one type of synaptic plasticity, typically requires electrical stimulation. Using rat hippocampal slices, we show that increasing the Ca 2+ of the extracellular solution to 4 mM and decreasing the Mg 2+ to 0.1 mM induced LTD in the CA1 region in the absence of electrical stimulation. The ionically-induced-LTD occluded electrical stimulation-induced LTD and was not blocked by application of 50 μM d -2-amino-5-phosphonopentanoic acid (an N -methyl- d -aspartate receptor antagonist) or by 1 mM (RS)-alpha-methyl-4-carboxyphenylglycine (a metabotropic glutamate receptor antagonist) alone. However, LTD was not ionically induced in the presence of both inhibitors. Our findings suggest that altering tissue excitability by changing the ionic environment mimics electrical stimulation in the induction of LTD.

Catalytic degradation of high density polyethylene (HDPE) and polypropylene (PP) were carried out in this work in a powder-particle fluidized bed with inside diameter of 25 mm. Two kinds of catalysts (F9; Silica/Alumina,SA) were used as medium particles fluidized by nitrogen. The yields of liquid fuel, gas product and solid residue were investigated under different operating conditions, including catalyst type, bed temperature, superficial gas velocity. The compositions of liquid and gas products were also determined by gas chromatography. Between two kinds of catalyst, SA can produce higher yield of liquid fuel and more valuable gas product under temperature range from 400 to 550°C. Over 86 wt.% conversion of liquid fuel, containing hydrocarbons from C-5 to C-11, was reached from both HDPE and PP under 500°C with a residue yield level of less than 8 wt.%. Gas product under appropriate operating conditions contains over 59 wt.% ethylene and propylene.

The elutriation of fine powders (group C or group A powders in Geldart’s classification) from a fluidized bed of fine-coarse particle mixtures in a steady state is investigated. FCC and alumina particles of 12 μm to 91 μm in diameter (group C and group A powders) were used as fines. Alumina particles of 69 μm to 650 μm in diameter (group A and group B particles) were used as coarse particles. The effects of the weight fraction of powder in the bed, superficial gas velocity, size of fine powder, size of coarse particle, and mean diameter of bed particles on the elutriation rate constant were investigated.The following results are obtained. The elutriation rate constant of group A particles is affected by the properties of the elutriated particles and gas and by operating conditions such as gas velocity. However, the elutriation rate constant of group C powders is not only affected by the above conditions, but also by the weight fraction of the elutriated powder in the bed and sizes of both coarse particles and elutriated powder in the bed, that is, the mean diameter of the bed particles. The elutriation rate constant of group C powders decreases with increases in the mean diameter of bed particles and with decreases in the size of group C powders under the condition of a constant superficial gas velocity. This finding is quite different from that of elutriation of group A or group B particles.

Pore size distribution and mean pore diameter of calcined lime powder produced by a powder-particle fluidized bed were measured and the effects of reaction temperature, average residence time of gas in the bed, CO2 and conversion of limestone were investigated. In CO2- free atmosphere, small pores of less than 100A were mainly observed in the calcined lime. The mean pore diameter increased with the superficial residence time of gas in the bed, which is defined as the static bed height divided by the superficial gas velocity. When the superficial residence time of gas in the bed was constant, a strong relationship was found between the conversion of limestone and the mean pore diameter of calcined lime. Through this study, it was shown that calcium oxide powders with various pore structures can be easily produced in very short residence time of gas by the powder-particle fluidized bed.

A powder-particle spouted bed (PPSB) is proposed for removal of SO2 from flue gas. Experimental results of a bench scale process show that, in addition to the known advantages in a semidry desulfurization process, a PPSB enables more efficient SO2 removal. However, quantitative investigation of the relationship between SO2 removal efficiency and the influential factors is still needed before a PPSB can be used in the flue gas desulfurization industry. In this paper, based on the analysis of chemical reaction and mass transfer between sorbent particles and flue gas, a method for analyzing the SO2 removal efficiencies in the semidry desulfurization process with a PPSB is proposed. The relations of SO2 removal efficiency to such parameters as stoichiometric ratio, approach to saturation temperature, and sorbent particle diameter are established. The desulfurization efficiency is numerically simulated by this method. Comparison of the calculated results with the experimental data shows that this method is of satisfactory reliability for prediction of SO2 removal efficiency in this new flue gas desulfurization process.

Porous quicklime powder is produced from 5 μm limestone particles in a Powder-Particle Fluidized Bed (PPFB). PPFB is a new fluidization technique in which agglomerative fine particles adhere onto the surface of the fluidized coarse particles, and are co-fluidized in the bed. For 5-μm limestone calcined with dry air at 1073 to 1223 K, the PPFB yields the lime powder with BET specific surface areas of 15 to 60 m2/g, depending on the residence time of gas in the PPFB. Measurement of the total pore volume of produced lime reveals a maximum value of 0.178 cm3/g, which is much higher than those obtained by conventional methods. However, the pore volume of the lime produced at 1173 K with gas containing CO2 is almost constant, regardless of the residence time of gas. This can be caused from the fact that the CO2 effect on mild sintering surpasses the temperature-promoted sintering. From this study, the lime powder that has very large BET specific surface and large pore volume can be produced by this method.

This paper is devoted to establishing a simple correlation calculating the equivalent diameter of clusters in gas-solid how. Three different kinds of cluster sizes were distinguished in accordance with the measuring techniques: (1) vertical length measured with optical fiber or capacitance probes; (2) cross-sectional size determined with image analysis of graphs taken by video camera or other suitable detection systems; and (3) hydrodynamic equivalent diameter of clusters derived from differential pressure drop (solid concentration) via appropriate fluid dynamic models. The hydrodynamic equivalent cluster diameter correlated in hydrodynamic modeling was generalized as the diameter of spheres (uniform in size) having the same total volume as actual dusters (not a single cluster), which is subject to hydrodynamic equations, such as force balance, for clusters. It was demonstrated that hydrodynamic equivalent cluster diameter is close to cross-sectional size, but much less than vertical length of clusters experimentally measured. The correlation reported in Xu and Li (1998) (Chem. Engng Sci., vol. 63, p. 1349) was found to be capable of predicting hydrodynamic equivalent cluster diameters of heterogeneous gas-solid systems for both Geldart A and Geldart B particles, which was then further simplified for facilitating its practical use. (C) 1999 Elsevier Science Ltd. All rights reserved.

The collapse of dilute suspension was studied in three different circulating fluidized bed (CFB) risers with two types of particles. The risers had the same height of 3.0 m but different inner diameters of 66 mm, 97 mm and 150 mm, respectively. FCC particles (Geldart A) and silica sand particles (Geldart B) were used. It was found that the collapse of dilute suspension is characterized by rapid accumulation of particles at the riser bottom, independent of the riser diameter and the types of particles. In accordance with the observation, an approach was developed to determine the collapsing point from experimental measurements. Then, the dilute suspension collapse was found to be dominated by an identical differential pressure drop at the riser bottom. This critical pressure drop is independent of gas velocity and riser diameter, whereas varies with the properties of particles. Riser diameter has different influences for FCC and silica sand particles upon the saturation carrying capacity, the solids circulation rate at the dilute suspension collapse. Under a given gas velocity, the collapse in a larger riser is observed to take place at a larger solids circulation rate for FCC, but at a smaller solids circulation rate for silica sand. This diversified dependence on riser diameter of the saturation carrying capacity was identified as a result of the different influences of the riser diameter on the bed density for those two types of particles. On a etudie la rupture de la suspension diluee dans trois colonnes montantes a lit fluidise circulant (CFB) avec deux types de particules. Les colonnes avaient la meme hauteur de 3,0 m mais differents diametres interieurs, soient 66 mm, 97 mm et 150 mm. Des particules de FCC (Geldart A) et de sable de dice (Geldart B) ont ete utilisees. On a trouve que la rupture de la suspension diluee se caracterisait par I'accumulation rapide de particules au fond de la colonne montante, independamment du diametre de la colonne et du type de particules. Conformement a cette observation, on a developpe une approche afin de determiner le point de rupture a partire de mesures experimentales. On a trouve ensuite que la rupture de la suspension diluee etait dominee par une perte de charge differentielle identique au fond de la colonne. Cette perte de pression critique est independante de la vitesse de gaz et du diametre de la colonne, tandis qu'elle vane avec les proprietes des particules. Le diametre de la colonne exerce differentes influences pour les particules de FCC et de sable de silice sur la capacite de transport de la saturation et la vitesse de circulation des solides a la rupture de la suspension diluee. Pour une vitesse de gaz donnee, on a observe que la rupture dans une colonne montante plus large se produisait a une vitesse de circulation des solides plus grande pour les FCC, mais e une vitesse de circulation des solides moins grande pour le sable de silice. Cette difference de dependance par rapport au diametre de la colonne montante de la capacite de transport de la saturation nous apparait comme resultant de differentes influences du diametre de la colonne sur la masse volumique du lit pour ces deux types de particules.