Influence of cold-rolling and annealing conditions on formability of aluminium alloy sheet

Using an Al-Mg-Cu alloy developed for auto body panels, strip sheets are experimentally produced by various cold-rolling and annealing procedures. Tensile and metallographic properties of the sheets and their relations are examined to attain high formability. The elongation is closely related to the grain size, and increases with the final annealing temperature. The rolling texture influences the plastic anisotropy, the Lankford value of the sheets. The comparatively high Lankford values are obtained under the condition that both the intermediate and the final annealing temperatures are higher and the reduction ratio after the intermediate annealing is smaller.     

Prediction of mill load in hot strip mill rolling

It has been ascertained whether or not the model capable of predicting the stress-strain relation of plain carbon steels, previously proposed, is applicable to the estimation of mill loads in the finishing process (consisting of six mill stands) of a hot strip mill. An appreciably good agreement with the predicted and measured mill load values has been obtained in the earlier passes where the strip microstructure is regarded to have completed static recrystallization, and the predicted mill loads in the later passes have been far less than the measured load owing to the effect of the strain accumulated in the previous rolling process. Then, a simple model to predict the accumulated strain has been constructed and introduced into the calculation of mill loads. As a result, the predicted mill loads have been fairly improved over the whole passes in the finishing process.     

Suppressive effect of functional drinking yogurt containing specific egg yolk immunoglobulin on Helicobacter pylori in humans

Helicobacter pylori is a human pathogen that infects over 50% of the population worldwide. It is the most important etiologic agent of gastroduodenal ulcers and malignancies. Helicobacter pylori urease enzyme is considered the main factor for the organism's colonization in the gastroduodenal mucosa. Hens immunized with the purified urease produce a highly specific anti-H. pylori urease immunoglobulin (IgY-urease) in their egg yolks. Immunoglobulin Y-urease was stable at 60 to 65 degrees C for 30 min and at pH 4.0 for 7 h. Its activity was lost at 80 degrees C for 20 min and at pH 2 for 4 h. Specially designed functional drinking yogurt containing Lactobacillus acidophilus and Bifidobacterium spp. with 1% egg yolk IgY-urease was produced commercially. Immunoglobulin Y-urease activity showed stability in the product up to 7 d, and then decreased to 85% after 3 wk of storage. A clinical study was conducted to determine the effectiveness of IgY-urease yogurt to suppress infection in humans. Forty-two volunteers who tested positive for H. pylori using a 13C-urea breath test were recruited. A total of 450 mL of IgY-urease (test group) or IgY-urease-free yogurt (control group) was consumed in 150-mL portions 3 times daily for 4 wk. Volunteers were tested after 2 and 4 wk; urea breath test values significantly decreased in the test group compared with the control group. The results indicate that suppression of H. pylori infection in humans could be achieved by consumption of drinking yogurt fortified with IgY-urease.     

Gas chromatography of dimethylalkylsilyl ether derivatives of bile acid methyl esters

The gas chromatographic separation of the DMAS ether derivatives of ten bile acid methyl esters, namely DMES, DMnPS and DMiPS ethers, have been studied by use of an open tubular glass capillary column, coated with SE-30. The DMAS ether derivatives were eluted in sequence according to the number of hydroxyl groups except of 12-KCDCA, and separated. This contrasts with the poorly resolved gas chromatographic peaks produced by the TMS ether derivatives. The DMES ether derivatives were resolved and baseline separation in 30 min, but those of HCA and 12-KCDCA had similar methylene unit values.     

Heat capacity measurements by means of thermal relaxation method in medium temperature range

The thermal relaxation method is used to measure heat capacities of small samples in the temperature range around room temperature. The calorimeter is designed to measure under heat exchange gas and a steplike excess heat is applied to the sample by irradiation from a lamp.     

单向纤维复合材料的偏轴实验方法开发与评价(英文)

This study presents an integrated method suitable for off-axis tension and compression testing in unidirectional composites,and its application to the testing of in-plane shear characterization.A new rotating-grip test fixture,incorporating the attractive features of the existing pinned-end fixture and hydraulic wedge grips,has been developed.The proposed gripping system consists of two sets of jaw faces,each with a pair of self-aligning bearings that allows for loading in the axial and radial directions.Fi...     

SMS fibre structure for temperature measurement using a simple intensity-based interrogation system

A singlemode-multimode-singlemode (SMS) fibre structure for temperature measurement that utilises a simple intensity-based interrogation system is proposed. The temperature dependence of the SMS fibre structure utilised as a sensor is investigated numerically and experimentally. It is found that a strong temperature dependence for the SMS fibre structure exists at selected wavelengths. The temperature characteristic at such wavelengths is linear in nature and can be used for temperature measurements. The proposed temperature sensor offers a high resolution and accuracy, and also benefits from a simple configuration and low cost when compared to other fibre-optic temperature sensors.     

Physiological properties of the Mauthner system in the adult zebrafish

We investigated the morphological and electrophysiological properties of the Mauthner (M-) cell and its networks in the adult zebrafish (Danio rerio) in comparison with those in the goldfish (Carassius auratus). The zebrafish M-cell has an axon cap, a high resistivity structure which surrounds the initial segment of the M-axon, and accounts for an unusual amplification of the fields generated within and around it. Second, extra- and intracellular recordings were performed with microelectrodes. The resting potential was approximately -80 mV with an input resistance of approximately 0.42 M omega. The M-cell extracellular field was large (10-20 mV), close to the axon hillock, and the latency of antidromic spikes short (approximately 0.4 milliseconds), confirming a high conduction velocity in the M-axon. The extrinsic hyperpolarizing potential (EHP), which signals firing of presynaptic cells and collateral inhibition, was markedly lower at frequencies of spinal stimulation > approximately 5/second, suggesting an organization of the recurrent collateral network similar to that in the goldfish. Inhibitory postsynaptic potentials (IPSPs) were highly voltage-dependent; their decay time constant was increased by depolarizations. The presynaptic neurons which are numerous could be identified by their passive hyperpolarizing potential (PHP) produced by the M-spike current. Auditory responses, mediated via mixed synapses (electrical and chemical), had short delays and hence are well suited to trigger the escape reaction. The similarities of their properties indicate that the wealth of information generated over decades in the goldfish can be extrapolated to the zebrafish.     

Impulse creeping discharge characteristics in insulating oils with EHD function reinforced by added HFC gas components

The basic properties of electrohydrodynamic (EHD) pumping and dielectric strength were examined for two insulating oils, rapeseed ester oil and silicone oil, which were denatured by a bonding of hydrofluorocarbon (HFC)134a gas components decomposed using a barrier discharge reactor. In this work, the mechanism of a pure conduction pumping contributed to the evaluation of the electrical pumping in sample oils. Dielectric strength of oils was evaluated from the impulse creeping discharge characteristics and the 60 Hz breakdown voltage test. Experimental results revealed that the creation of radicals such as C-F and C-H in denatured oils led to a slight deterioration of the insulation ability compared to standard oils, but the pumping ability was reinforced significantly. Such additional EHD function may be utilized as a new cooling method in oil-filled power apparatuses in view of the dielectric strength.     

Beitrag zur rechnerischen Ermittlung der Temperaturverteilung in Warmwalzen

Rechnerische Ansätze zum Ermitteln der Temperaturverteilung im Walzeninnern. Walzenoberflächentemperatur im Walzspalt und außerhalb des Walzspaltes. Berechnungsbeispiel.