Isolation and Structure of a New Vitamin B6 Conjugate in Rice Bran

A major form of vitamin B₆ in rice bran was isolated by various chromatographic techniques as colorless powder. It was identified as 5′-O-[6-O-((+)-5-hydroxy-dioxindole-β-acetyl)-β-cellobiosyl] pyridoxine by spectroscopy, and enzymatic and chemical hydrolyses.     

Calcium Treatment to Maintain Quality of Zucchini Squash Slices

Zucchini squash slices dipped in solutions of CaCl₂ alone or with chlorine were stored at 0°C, 5°C, and 10°C. Slices developed water soaked areas (chilling injury) at 0°C and brown discoloration at 5°C and 10°C, which increased with storage. The amount and severity of chilling injury/browning/decay of water-dipped controls were least at 5°C. Calcium treatments helped in reducing development of decay, rate of total microbial growth, ascorbic acid loss, and shear force decrease of slices stored at 0°C and 10°C but not at 5°C. Addition of chlorine to CaCl₂ seemed to have some benefits at 0°C or 10°C.     

NiFe alloy particles doping effect of Gd–Ba–Cu–O bulks processed by a new cold-seeding technology

The process of cold seeding melt growth of GdBa₂Cu₃O_y (Gd123) bulk superconductors using NdBa₂Cu₃O_y (Nd123) thin films was reported. In addition, a novel cold seeding concept of combining MgO crystal and buffer pellet was also introduced. The misorientation caused by the lattice mismatch between MgO and Gd123 melt was overcome by choosing suitable heat treatment program and Gd₂BaCuO₅ (Gd211) content of the buffer pellet. The doping effect of soft ferromagnetic NiFe alloy particles was also reported. The bulk sample with 0.4% (mole fraction) doping amount shows the best performance on the flux trapping. The critical current density is largely enhanced under the external field of 1–2 T, which is promising for large-scale applications. This effect is originated from the substitution of Fe and Ni ions for the Cu sites contributing to magnetic flux pinning.     

机器人机械手臂关节驱动控制系统设计

基于动态方程和Hamilton-Jacobi原理,从硬件到软件,设计了机器人机械手臂的关节驱动控制系统。主要任务是使该系统的能耗最小化。仿真和实验的结果,证明了该系统的可用性和准确性。     

Lability and Reactivity of Nonheme Protein-Bound Nitrite

Nitrite treated nonheme protein was separated from the free nitrite of the reaction mixture by Sephadex G-15 column chromatography. Spectral analysis (absorbance at 330 nm) indicated that tryptophyl residues of the protein had been modified with the NO group. The protein-nitrite complex was not stable, decomposing faster at lower pH and higher temperature. As the extent of the decomposition increased with time, an increasing amount of nitrite was detected by the AOAC method, indicating that the Griess reagent reacted with nitrite after it was regenerated from the NO group. When myoglobin was incubated with the nitrosated protein, nitrosyl hemochrome could be extracted from the reaction mixture in the presence of ascorbic acid. The results indicate the potential reversibility of the protein-nitrite reaction.     

The morphology of isotactic polystyrene crystals grown in thin films: the effect of substrate material

Thin isotactic polystyrene films (∼50 nm thick) have been crystallized from the melt on various substrate materials (carbon, glass, mica, polyimide sheet and silicon). The morphology of the crystals has been examined using atomic force microscopy, and was found to be dependent on the nature of the substrate, with two basic types of crystal forming. Crystals either develop around giant screw dislocations, or around small bundles of lamellae growing perpendicular to the substrate surface. It has further been observed that the number of screw dislocations generated in the lamellae is also dependent on the substrate, as is the growth rate of the spiral terraces. These effects are interpreted in terms of interactions between the molecules in the melt and the substrate surface. This revised version was published online in November 2006 with corrections to the Cover Date.     

Ultraviolet-emitting ZnO thick layer grown by thermal oxidation with gallium

The Zn O layer with thickness of 1.6 μm in Zn O/Zn Ga2O4 composite structure was grown by the thermal oxidation of Zn S substrate with gallium. The optical property of the Zn O thick layer was investigated by time-resolved photoluminescence. A single UV emission around 375 nm with short lifetime was observed at room temperature while the visible emission was absolutely quenched. The UV emission band was composed of the neutral donor bound exciton(D0X) and donor-acceptor pair(DAP) emission peaks with large full-width at half-maximums(FWHMs) at 3.367 and 3.318 e V, respectively, at 10 K. However, the intensity of the D0 X emission was stronger than that of the DAP emission at measuring temperatures of 10–300 K.     

Calcium Treatments Affect Storage Quality of Shredded Carrots

Carrot shreds, sticks and slices were dipped in solutions of CaCl₂ alone, or with chlorine and stored at 0, 5 or 10°C to determine the effects of calcium (Ca) on storage quality. A 0.5% or 1% CaCl₂ treatment maintained firmness and reduced microbial growth of carrot shreds at all temperatures. These treatments also resulted in lower tissue pH than in the water-dipped controls. Treatments increased Ca content slightly in sticks and slices and substantially in shreds and had no effect on storage quality of sticks or slices.     

Reaction of Nitrite and Cytochrome c in the Presence or Absence of Ascorbate

The reaction of nitrite with cytochrome c in the presence or absence of sodium ascorbate was studied. The amount of ferrocytochrome c nitrosyl compound I (cytochrome c · Fe²⁺-NO⁺) formed in the absence of ascorbate was dependent on pH both at initial equal concentrations of nitrite or nitrous acid; the amount formed was very small at pH above 5.0. The presence of ascorbate significantly enhanced the extent of the reaction in the pH range 5.0–6.0. The reaction decreased rapidly at pH above 6.0, but application of heat was effective in giving a large formation of the product. Ascorbate reduced compound I to ferrocytochrome c nitrosyl compound II (cytochrome c · Fe²⁺-NO). The relative amounts of the two compounds formed was influenced by pH; at pH below 3.6, a mixture of compound I and II was formed, but only compound II was formed above pH 3.6. Compound II easily gave rise to ferrocytochrome c Cytochrome c probably reacts with nitrite in cured meat if ascorbate or erythorbate is used.