Retention of Phytochemicals in Fresh and Processed Broccoli

Our objective was to determine whether steam blanching, storage and preparation affected concentrations of sulforaphane (SF), sulforaphane nitrile (SFN), cyanohydroxybutene (CHB), iberin (I) or iberin nitrile (IN) in fresh and frozen broccoli. Broccoli (var. “Arcadia”) was grown in St. Charles, IL over three seasons. Samples were steam blanched (2 min at 93 ± 5°C) within 24h of harvest, frozen and stored at ?20°C up to 90 days, and fresh broccoli was stored at 4°C up to 21 days. Samples were analyzed uncooked or microwave cooked. SF, SFN, I, IN and CHB were determined by GC in dichloromethane extracts from lyophilized samples. Rates of loss for CHB and SF were similar during storage of fresh broccoli. Blanching, storage, and microwave cooking decreased (p < 0.01) concentrations of each compound in fresh and frozen broccoli.     

Effect of Rub-Groove Wall Angle on the Leakage of Abradable Stepped Labyrinth Seals

Rub grooves are generally formed in gas-turbine labyrinth seals of the abradable type during various transients. The rub-groove shape, often the slope angle of the groove downstream wall, varies and largely depends on the rotordynamics and the thermal expansion rates of the rotor and the stator. The effect of rub-groove shape on stepped labyrinth seal leakage was studied by varying the slope angle of the groove downstream wall, using various tooth axial positions and various prerub radial clearances. The investigation was done for compressible flow, with air as the working fluid. A finite volume method was used to solve the two-dimensional axisymmetric, Reynolds-averaged Navier-Stokes equation system. The high-Reynolds-number k-? turbulence model was used along with wall functions. It was found that the wall angle of rub groove has a significant effect on the leakage as well as on the flow pattern. For the cases considered here, when the seal operates with the tooth positioned axially within the rub-groove axial width, the leakage decreases with an increase of the rub-groove downstream wall slope angle. However, for operation when the tooth lies axially just downstream of the groove, the leakage is slightly increased with an increase of the rub-groove wall angle. For cases with a certain tooth axial position and prerub radial clearance, a small change of groove sloping wall angle results in a large change in flow pattern.     

SOYBEAN LIPOXYGENASE-I CATALYSED EXCHANGE OF MOLECULAR OXYGEN IN 13-S-HYDROPEROXY-9-CIS, 11-TRANS OCTADECADIENOIC ACID

Soybean lipoxygenase-I was incubated with ¹⁸O₂- 13-S-hydroperoxy 9-cis, 11-trans octadecadienoic-acid. It was shown, by ¹⁸O content, degree of racemisation and of isomerisation that the enzyme catalysed the exchange of molecular oxygen with the oxygen atoms of the OOH group which is stereoselectively retained in the 13(S) conjiguraton after exchange .     

Dynamic Fatigue of a Machinable Glass-Ceramic

To assess the stress-corrosion susceptibility of a machinable glass-ceramic, its dynamic fatigue behavior was investigated by measuring its strength as a function of stress rate. Fracture mechanics techniques were used to analyze the results for the purpose of making lifetime predictions for components of this material. This material was concluded to have only moderate resistance ( N =30) to stress corrosion in ambient conditions. The effects of specimen size on strength were assessed for the material used in this study; it was concluded that the Weibull edge-flaw scaling law adequately describes the observed strength-size relation.     

Investigation of the System CaO-MgO-V2O5: II, Crystalline Solutions and Crystal Chemistry

The extent of the crystalline solutions in the system CaO-MgO-V₂Os was studied quantitatively by the determination of lattice parameters. Metavanadate solutions existed along the length of the CV-MV join, while the defect garnet solutions occurred at 29 to 32 mol% MgO on the orthovanadate join. The addition of solute ions created structural changes in the directions of the polyhedral layers (a- and c-axis directions). Little change was reflected in the direction of polyhedral chains ( b-axis direction). The amount of solute allowed into the host lattices was structurally limited due to the significant differences in size between Mg²⁺ and Ca²⁺.     

BTN1, a Yeast Gene Corresponding to the Human Gene Responsible for Batten's Disease,is Not Essential for Viability,Mitochondrial Function,or Degradation of Mitochondrial ATP Synthase

The Saccharomyces cerevisiae gene BTN1, encodes a 408 amino acid putative integral membrane protein, which is 39% identical and 59% similar to the human Cln3p, whose mutant forms are responsible for Batten's disease and for a diminished degradation of mitochondrial ATPase synthase subunit c. Disruption experiments established that Btn1p is not essential for viability, mitochondrial function, or degradation of mitochondrial ATP synthase in yeast. © 1997 John Wiley & Sons, Ltd.     

EARTHQUAKE RESPONSE OF STRENGTHENED STEEL SPECIAL MOMENT RESISTING FRAMES

This paper presents the response of steel moment resisting frames with damage to their welded connections for two repair options: (1) reweld only; and (2) reweld and strengthen connection. Two different nonlinear dynamic analysis programs are used to research the effect of repairing and strengthening these weld failures and also for predicting the expected building response assuming that the connection is not repaired. The effect on response is studied for connections where weld failure reduces the capacity to 50, 20 and 5% of the original moment capacity. The frames selected for the research are in a real building damaged during the Northridge earthquake. They are subjected to an ensemble of artificial earthquake records that have an equal probability of occurring at the site for comparative studies. © 1997 John Wiley & Sons, Ltd.     

NONLINEAR DISCRETE-TIME RISK-SENSITIVE OPTIMAL CONTROL

This paper is devoted to the study of the connections among risk-sensitive stochastic optimal control, dynamic game optimal control, risk-neutral stochastic optimal control and deterministic optimal control in a nonlinear, discrete-t ime context with complete state information. The analysis worked out sheds light on the profound links among these control strategies, which remain hidden in the linear context. In particular, it is shown that, under suitable parameterizations, risk-sensi tive control can be regarded as a control methodology which combines features of both stochastic risk-neutral control and deterministic dynamic game control.     

输入/损失技术

输入 /损失技术 ,是一项独一无二的技术 ,它通过对燃料及其渗漏的流动、燃料化学性质、燃料热值和热效率的分析 ,为全面理解电厂热力过程创造了条件。低位 (净 )发热量与高位 (总 )发热量和热效率可以确定 ,而直接的燃料流量或排放物流量的测量没有给定。鉴于打算将其用于燃煤电厂 ,输入 /损失技术是根据透平循环的能量流动和锅炉运行特性 ,通过迭代技术与发散测量方法来确定煤的流动与燃烧热值的。发散测量方法 ,是以多维最小化技术来校正的。多维最小化技术对于给定的煤种可以校正燃料的特性参数在小于±2 %的标准误差范围内 ,校正后的结果可以证明是基本稳定的。典型的热值可以在 0 .5 %的精确度下进行预测。它是为在线监测器而设计的。这种方法已经被 1 2 0 0次元素分析和 1 0年的指导性测试结果广泛验证。图4表 3参 2 0