N2‐Plasma‐Assisted One‐Step Alignment and Patterning of Graphene Oxide on a SiO2/Si Substrate Via the Langmuir–Blodgett Technique

Precise control of the placement and patterning of graphene on various substrates has tremendous impact in many fields, such as nanoscale electronics, multifunctional optoelectronic devices, and molecular sensing. A one‐step facile technique involving N₂‐plasma promotes surface modification and enhances the surface wettability of the substrate. The technique is employed to create partially hydrophilic surfaces on SiO₂/Si substrate with the aid of various templates, enabling the selective deposition, alignment, and formation of patterns comprising monolayer graphene oxide (GO) sheets; it successfully uses the Langmuir–Blodgett (LB) deposition technique over a large area without the need of any sophisticated equipment. Various characterization techniques are carried out in order to understand the possible mechanism behind the pinning of the GO on the partially treated areas. It is a relatively easy and swift process that can reliably accomplish specific surface modification with high bonding strength between GO and the substrate. This technique allows the creation of patterns with controllable dimensions. For example, the thickness of the GO sheets can be controlled; this is particularly important in creating arrays and devices at wafer‐scale. Being simple yet effective and inexpensive, this technique holds tremendous potential that can be exploited for numerous applications in the field of bio‐nanoelectronics.     

In‐gel detection and study of the role of flavonol 3‐glucosidase in the bitter taste generation in tartary buckwheat

The present study demonstrated that flavonol 3‐glucosidase (f3g) is an important cause of bitter taste generation in tartary buckwheat (Fagopyrum tataricum) flour using the f3g complement test. To screen the f3g deletion line, which must have little bitter taste, an in‐gel method to detect individual f3g isozymes in tartary buckwheat seeds was developed. The f3g isozymes in tartary buckwheat seed were stained using a rutin–copper complex on the native–PAGE gel. This method was able to clearly detect as little as 1.4 ng of individual f3g isozymes within 20 min following electrophoresis. With this method, screening of the f3g deletion line can be conducted efficiently and will result in a better taste in tartary buckwheat flour. Copyright © 2004 Society of Chemical Industry     

Preparation of oxidized 6-O-glycolchitosan,pH sensitivity of its aqueous solution and of its cross-linked hydrogel

Chitosan and 6-O-glycolchitosan, a water-soluble chitosan derivative, were oxidized by periodate. In the case of chitosan, only degradation products were obtained. With 6-O-glycolchitosan, however, water-soluble amphoteric polyelectrolyte derivatives of chitosan having higher molecular weight were obtained. The oxidized 6-O-glycolchitosan (OX-GC) showed a pH sensitive change of viscosity in aqueous solution. Moreover, the OX-GC hydrogel, cross-linked with glutaraldehyde, showed a pH sensitive swelling behavior. The OX-GC showed biodegradation behavior by lysozyme after acetylation.     

下部调剂对高炉炉料运动影响的离散模拟

应用三维离散元法对4 000m3高炉内的炉料运动行为进行研究.结果表明:鼓风动能增加,风口回旋区加深并没有改变高炉上部的料层结构与分布状况,而是使得高炉下部死料柱变小、变矮,其对上部炉料的支撑作用减弱,致使上部炉料的下降速度明显增大,冶炼强度得以提高.风口中心线以上2m处炉腹段,炉料的运动速度与应力分布趋于均一化.堵风...     

Controlling the resistivity of multi-walled carbon nanotube networks by copper encapsulation

The resistivity of multi-walled carbon nanotube networks can be changed by filling Cu into the nanotubes as well as by preparing the nanotube networks with various densities. The resistivity can be controlled to be lower than the c-axis resistivity of graphite, and has a low temperature coefficient of ?1.12 × 10^?5/K over the temperature range of 20–500 K. Filling Cu into the nanotubes decreases the intra-tube resistivity, but the temperature coefficient of the resistivity is governed by the inter-tube resistivity of the nanotube network.     

Analysis on Non‐Uniform Gas Flow in Blast Furnace Based on DEM‐CFD Combined Model

Blast furnace technology is currently aiming at low reducing agent operation so as to decrease CO₂ emissions. At the same time, the inner volume of blast furnaces has frequently been enlarged so as to increase production rate in some countries, including Japan. Operating conditions designed for low reducing agent in a large blast furnace tend to cause unfavorable phenomena such as slipping of the burden and gas channeling due to the decrease in coke rate. Mathematical models help to clarify the in‐furnace phenomena under these situations. From the above backgrounds, a new model has been developed that combines Discrete Element Method with Computational Fluid Dynamics (DEM‐CFD) to simulate precisely the gas flow and solid motion in a blast furnace. The present study aimed to develop a three‐dimensional mathematical model based on DEM‐CFD for simultaneous analysis of gas and solid flow in the whole blast furnace. The unbalanced gas flow in the case of clogging of the particular tuyere was analyzed to clarify the circumferential unevenness in the lower part of the blast furnace. Based on the combined DEM with CFD model, the non‐uniform gas flow in the lower part of the blast furnace was precisely evaluated.     

The Depressive Effects of 5,8,11-Eicosatrienoic Acid (20:3n-9) on Osteoblasts

In cases of essential fatty acid deficiency, 5,8,11-eicosatrienoic acid (Mead acid, 20:3n-9) is synthesized from oleic acid as a 20-carbon analog of arachidonic acid. It was reported that 20:3n-9 levels were markedly higher in human fetal cartilage than in the muscle, liver and spleen. We, therefore, hypothesized that 20:3n-9 decreased osteoblastic activity. Goldfish scales were incubated either with 20:3n-9 or with oleic acid at 15 °C for 6 and 18 h. Both osteoblastic and osteoclastic activities in the scale were assessed by measuring alkaline phosphatase (ALP) and tartrate-resistant acid phosphatase, respectively. MC3T3-E1 cells (an osteoblast cell line derived from the mouse) were incubated with 20:3n-9 or oleic acid at 37 °C for 6 and 18 h. ALP activity in cell lysate was measured. In the case of experiments with scales, 20:3n-9 (1–100 μM) significantly suppressed osteoblastic activity after 6 and 18 h of incubation, whereas oleic acid did not change this activity. Osteoclastic activity was not affected either by 20:3n-9 or by oleic acid. In the case with the cell line, osteoblastic activity was again significantly decreased with 20:3n-9 (10–30 μM) after 6-h incubation but not after 18 h incubation. The presence of 20:3n-9 in fetal cartilage may be important for the prevention of calcification in the cartilage. 20:3n-9 could be applied to some clinical situations where bone formation should be inhibited.     

Molecular characterization of the Tim9 homologue from the methylotrophic yeast Pichia methanolica

In this paper we describe molecular characterization of the TIM9 gene encoding the essential mitochondrial inner-membrane protein in the methylotrophic yeast Pichia methanolica. PmTIM9 contains two exons corresponding to a gene product of 89 amino acid residues and a 140 bp intron. The deduced amino acid sequence exhibited high identity to those of other yeast Tim9ps, and possessed two CX(3)C motifs that contained two cysteine residues conserved among small Tim family proteins. Moreover, PmTIM9 had the ability to partially suppress the temperature sensitivity of Saccharomyces cerevisiae strain tim9-3, suggesting that PmTIM9 is a functional homologue of the ScTIM9 gene.     

Characterisation of cellulose treated by the steam explosion method. Part 3: Effect of crystal forms (cellulose I,II and III) of original cellulose on changes in morphology,degree of polymerisaion,solubility and supermolecular structure by steam explosion

An attempt was made to clarify the effect of the crystal form of untreated cellulose on the morphological and structural changes of cellulose during steam explosion treatment (steam pressure P = 2.9MPa (T = 508K), treatment time t = 15-300 s). For this purpose, the crystal form of soft wood pulp (cellulose I) was converted by solid-to-solid transition, with minimal unavoidable change in other structural characteristics including morphology and average degree of polymerisation, into cellulose II or cellulose III. It was proved by both X-ray and solid-state cross-polarisation/magic-angle sample-spinning (CP/MAS) ¹³C NMR analyses that even a simple addition of water at room temperature brought about a significant structural change in the steam-untreated cellulose samples. The solubility towards 9.1 wt% aqueous sodium hydroxide, S_a, of the cellulose samples of crystal forms I and III could be improved from 31-33% up to almost 100% by selecting appropriate steam explosion conditions (for example, P = 2.9MPa, t = 30 s). Such a magnificent increase in S_a by the steam explosion treatment was not observed for the cellulose II sample, even under the rather severe conditions of the steam explosion treatment at which the cellulose III crystal was converted to a large extent to cellulose I, as confirmed by X-ray diffraction. X-ray diffraction analysis showed that crystallisation of samples with cellulose I or II crystal occurred to some extent during the steam explosion treatment. Contrary to this, the degree of breakdown of the intramolecular hydrogen bond O₃…O'₅, as estimated by CP/MAS ¹³C NMR analysis, significantly increased for cellulose I and I11 during the treatment. The decrease in the viscosity-average degree of polymerisation, P, observed for all treated samples can be roughly categorised into two or three steps of the first-order decomposition reaction with different reaction rates.