Low temperature—long time,high temperature-short time liquefaction of coal: The Hokudai process

A Japanese cola was hydrogenated in wash oil with fine iron dust and sulphur as catalyst under a reaction pressure of 12–13 MPa at 420 °C for 2 h and then at 500 °C for 0–20 min. The liquid yield boiling up to 600 °C amounted to 55–66 wt%. Pyridine conversion was ≈ 100 wt%, benzene conversion 82–90 wt% and n-hexane conversion 53–70 wt%. Compared with direct hydrogenation at 500 °C for 10 min the low temperature-long time plus high temperature-short time liquefaction process (the Hokudai process) is a very effective method for obtaining high liquid yield under relatively low hydrogen pressure without coking, using disposable catalyst and non-donor solvent.     

The new joint R&D

During the 1980s, a new form of collaborative research and development emerged in Europe, the US, and Japan. In this new form of joint R&D, companies that compete against one another join together for the purpose of creating new process technology in specified domains. This collaboration among competitors is justified for the development of technologies that many companies will ultimately use in a common manner. Such leaky technology typically cannot be effectively protected by patent or other means, and thus will not be developed except through collaborative means, in which those who benefit jointly incur the R&D expense. In Europe and Japan, governments typically provide 50-70% of the cost of such a joint project, while in the United States, government support for joint R&D is just now beginning to become available. The R&D collaboratives are described as being of two types: the secretariat, which is a coordinative body, and the operating entity, which operates its own R&D laboratory facilities. The conditions under which each organizational form appears, as well as the kinds of effort each form typically undertakes, are described     

Effects of daily administration of methamphetamine on multiple active/passive avoidance performance in rats

The effects of daily methamphetamine (M-Amp) treatment with (2 mg/kg/day, i.p.) were examined on multiple active/passive avoidance performance (MAP) in rats. After avoidance training, the animals were given M-Amp every day; on the days of learning sessions, which were on alternate days, the drug was administered at 15 min before the session. Daily administration of M-Amp produced enhancement of the number of respondings (running) as an excitatory dimension of behavior, disruption of immobilities as an inhibitory dimension, and impairment of successes as a discriminatory dimension, when compared with saline-treated rats. Following M-Amp withdrawal, recovery from these damages of learned behavior was observed, except the deterioration in the discriminative dimension. In conclusion, the MAP paradigm is good for assessing the behavioral effects of M-Amp treatment, making it easy to distinct the behavioral effects of M-Amp into excitatory-inhibitory and discriminative dimensions. It is important to distinguish the behavioral components induced by M-Amp, since the damage of learned avoidance performance consists of different dimensions in the M-Amp-treated rats. Impairment of discriminative behavior appears to demonstrate an attentional deficit, which may explain the behavioral disorderliness in M-Amp abusers who display no disturbance of apparent consciousness. These results are discussed with association of brain monoamine alterations.     

Cell cycle-dependent expression of estrogen receptor and effect of estrogen on proliferation of synchronized human osteoblast-like osteosarcoma cells

Dual fluoroimmunohistochemical staining of estrogen receptor (ER) and bromodeoxyuridine was performed in a human osteoblastic osteosarcoma cell line, HOS TE85 cells. ER immunoreactivity was observed preferentially in the nuclei of the cells that were bromodeoxyuridine positive. ER expression at various phases of the cell cycle was investigated in HOS TE85 cells, which were synchronized at the G1/S phase boundary by intermittent exposure to thymidine and hydroxyurea. ER immunoreactivity became detectable in the S phase, decreased in the G2/M and G1 phases, and then reappeared in the S phase of the next cell cycle. Western blot analysis also showed that ER protein exists in these cells and increases in the S phase. Moreover, Northern blot analysis demonstrated that the expression of ER messenger RNA increases in the early S phase, gradually decreases during the progress of the cell cycle, and increases again in the S phase of the subsequent cell cycle. Interestingly, 17 beta-estradiol (10(-8) M) increased cell number and [3H]thymidine incorporation into DNA in the synchronized HOS TE85 cells, whereas this effect was not observed in the nonsynchronized HOS TE85 cells. The present studies suggest that the cell cycle-dependent regulation may contribute to the heterogeneity of ER expression in osteoblastic cells.     

The origins of defects in sputtered Co-Cr perpendicular magneticrecording media

The authors examine various causes of contamination and the defects they produce, and they typify some defects that originate at the metal/substrate interface, as nodules or extraordinary particles. They find that these are not caused by dirt or mishandling, but are induced by an exudate from the polymide substrates used. The nodules' characteristic acorn shape can be analyzed mathematically to suggest a possible exudate-induced mechanism for their formation and growth. The authors conclude that most of these defects can be eliminated     

A 3-bit soft-decision IC for powerful forward error correction in 10-Gb/s optical communication systems

We describe the design concept and performance of a 3-bit soft-decision IC, which opens a vista for new terabit-capacity optical communication systems by dramatically improving the capability of forward error correction (FEC). The proposed soft-decision IC is composed of five functional blocks, i.e., a soft-decider, an error filter, a 3-bit encoder, a 3:48 de-multiplexer, and a clock recovery circuit. The biggest challenge was the soft-decision block regenerating the common data using seven deciders with separate thresholds. We employed a novel SiGe BiCMOS process and a custom BGA package made from low-temperature co-fired ceramics to achieve a high sensitivity of 20 mVpp with a wide phase margin of 270/spl deg/ for 12.4-Gb/s nonreturn-to-zero (NRZ) data signals. The error filter and the 3-bit encoder, which are incorporated in the IC, prevent the degradation of the FEC performance due to signal noise or fluctuations. The 3:48 de-multiplexer provides an accessible interface with the FEC encoder/decoder LSI. The clock recovery circuit, based on a phase-locked-loop technology, fulfilled the jitter tolerance requirements corresponding to ITU-T G.825, even for 55% duty cycle optical return-to-zero (RZ) signals. The 3-bit soft-decision IC, in cooperation with a block turbo encoder/decoder, achieved a record net coding gain of 10.1 dB with 24.6% redundancy, which is only 0.9 dB away from the Shannon limit for a code rate of 0.8 for a binary symmetric channel.     

Synthesis of nitrogen-rich B–C–N materials from melamine and boron trichloride

Nitrogen-rich B–C–N materials have been prepared by the reaction between melamine and boron trichloride at different temperatures. The composition of the materials was dependent on the synthesis and annealing temperatures: C6N10.8-11H9.4B1.5-1.7 (for products synthesized and annealed at 673 K), C6N9.3-9.4H3.8-3.9B2.2-2.5 (for those synthesized at 673 K and annealed at 873 K) and C6N9.2H3.6B1.2-1.3 (for those synthesized and annealed at 873 K). Fourier transform infrared spectroscopy and 13C nuclear magnetic resonance showed that the s-triazine rings from the melamine molecules were preserved in materials synthesized and annealed at 673 and 873 K. The sample obtained at 873 K had a graphite-like structure as suggested by X-ray and electron diffraction studies. The s-triazine rings were decomposed in the materials synthesized or annealed at 1223 K and the main product obtained was turbostratic boron nitride. © 1998 Chapman & Hall     

Reaction mechanism of coal hydrogenation: 2. Three rings solvent system

Taiheiyo coal was hydrogenated in phenanthrene, 9,10-dihydrophenanthrene, 1,2,3,4,5,6,7,8-octahydrophenanthrene and perhydrophenanthrene under 10 MPa (initial pressure) of hydrogen or nitrogen with or without stabilized nickel as catalyst at 400 °C for 15 min. Preasphaltene, asphaltene and oil conversions and the conversion of solvents were measured, and the amounts of hydrogen absorbed by coal from molecular hydrogen and from donor solvent were calculated. The main route of reaction appears to be the direct hydrogenation of coal by molecular hydrogen and the contribution of hydrogenation via the solvent was greater than in the case of the two rings solvent system.     

Vinyl polymerization: 414. Polymerization of vinyl monomer initiated by poly(N,N,N-trimethyl-N-2-methacryloxyethyl)ammonium chloride

The polymerization of vinyl monomer initiated by an aqueous solution of poly(N,N,N-trimethyl-N-2-methacryloxyethyl)ammonium chloride (poly(Q-DMAEM-CI) has been carried out at 85°C. The effects of the amounts of vinyl monomer, poly(Q-DMAEM-CI) and water on the conversion of vinyl monomer have been studied. The overall activation energy in the polymerization of MMA is estimated as 41.9 kJ mol^?1. The polymerization proceeds through a radical mechanism. The location in which the polymerization occurs is discussed. The selectivity for vinyl monomer is explained by ‘the concept of hard and soft hydrophobic areas and monomers’.     

Coking reaction in hydrogenation

Asphaltene prepared from a Japanese coal (Akabira, 81.2 wt% C) and coal tar pitch were heat treated under nitrogen or hydrogen. Under nitrogen the initial thermal decomposition produced radicals which abstracted hydrogen from other molecules to stabilize and to produce smaller molecules and gas. The molecules from which hydrogen was abstracted as well as other radicals polycondensed to produce heavier solvent-insoluble fractions. Under hydrogen the radicals were stabilized by hydrogen gas to produce smaller molecules avoiding the production of a heavier fraction. The higher the hydrogen pressure, the smaller was the yield of heavier fraction and the larger the yield of lighter fraction. Higher temperature accelerated the production of the heavier fraction. Donor solvents could reduce the production of the heavier fraction.