Single Dip Research Articles

Making Rubber Membranes

A simple procedure for making rubber membranes in the laboratory is described. The technique necessary in order to obtain good quality membranes of any shape and thickness in a single dip is outlined. Permeability tests indicate that practically leak-proof membranes can only be obtained after curing at elevated temperatures.

The (d, p) reaction anomaly at the threshold of the analogue channel and the p-wave neutron strength function

The anomaly is discussed in terms of the averaged S-matrix and the p-wave neutron strength function. It is shown that the neutron strength function determines the steructure of the anomaly (single dip, double dip) and the (d, p) background its form (symmetric, asymmetric).

The Forbush-decrease in cosmic-rays and the transit time of the modulating cloud

Fifteen cases of Forbush-decreases and their associated solar flares have been analyzed using the method of superimposed epochs for estimating the tendency of recurrence between the flares and the Forbush-decreases. The fifteen events are divided into two classes. Eleven events are characterized as the simple type consisting of one single sharp dip with a smooth recovery up to the undisturbed niveau. For this type the assembly of flares preceding the mean Forbush-decrease lies concentrated within a time interval of 2.2–3.2 days before the sharp decrease, with a maximum in recurrence at 2.7 days transit time corresponding to a mean particle speed of 640 km/sec. This simple type of event is thus being produced through a particle-cloud ejection from one single flare. The mean curve of the dip for this simple type shows an exponential-like decrease down to 2.8 per cent and a recovery up to normal niveau with time constants of respectively 4 hr and 3.2–3.5 days. Four great events are characterized as composite events, in these cases the associated flares appear almost evenly distributed over the surrounding days ranging from 3–4 days before to 7–8 days after the Forbush-decrease. The composite events, which last with almost uniform depression 7–8 days after the dip, are therefore being produced by successive series of solar flares, and the mean maximum decrease of the composite type was 7 per cent. When comparing the onset of the Forbush-decrease with the position of the SC of geomagnetic storm, the SC appears in mean about 3 hr before the sharp onset of the Forbush-decrease.

Residues of Dursban and its oxygen analog in the body tissues of treated cattle.

Residues of Dursban® (O,O -diethyl O -3,5,6-trichloro-2-pyridyl phosphorothioate) and its oxygen analog (diethyl 3,5,6-trichloro-2-pyridyl phosphate) present in the body tissues of cattle and the rate of elimination were determined after single spray treatments with 0.25 or 0.05% emulsions, a single dip with a 0.05% emulsion, and multiple dips with a 0.05% emulsion. The residues of Dursban were preponderant in the fatty tissues, and the low residues found in other tissues could be attributed to the small amount of fat present. Average residues in the fat of treated cattle 1 week after a single dip were about twice those resulting from a single spray treatment; average residue in the fat 1 week after the multiple dips was about 6 times that in the fat of cattle dipped once. The oxygen analog was found only in fat samples containing the higher residues of Dursban; they amounted to about 1% of the residue of Dursban.

Unitary responses to tone stimuli recorded from the medical geniculate body of cats

Unitary responses to tone stimuli obtained from the medial geniculate body were investigated in cats and the following results were obtained. 1)The unitsres ponding to tone stimuli were classified into 3 types.The first type showed a single spike or burst of spikes in response to the onset of tone stimulus.Thesecond type showed the response which consisted of asingle spike or a burst of spikes and a following silent period and then continuous firing.In the third type, theres- ponse was continuous firing with relatively long latency.The units of these types accounted for 86%, 6%and7%, respectively.2)Most units of the first type responded with a short latency of less than 20msec.In some of the rest, the latency of the response was more than 100msec.In the others, the latency was more than 100msec at high intensity, but less than 20msec at low infensity.3)In about 39% of the response areas obtained, eachshowed a single dip in its low intensity limit and in36%, two or more dips were observed.The remainder included many varieties.

Single mode tuning dip in the modulated power output of gas lasers

Single mode tuning dip in the modulated power output of gas lasers

Advances and developments in weather forecasting

Selectivity coefficients for sodium, calcium and potassium ion-selective electrodes estimated by traditional methods such as the separate solution and mixed solution methods are compared with values obtained by a more rigorous approach based on multivariate calibration using simplex optimisation and non-linear modelling of the array characteristics. The validity of the latter approach is demonstrated by using the models to predict the concentration of sodium, calcium and potassium in blood plasma and mineral water samples using dip and flow-injection analysis (FIA) measurements. For the array FIA data, the possibility of using an enhanced kinetic-based selectivity for analytical measurements is raised. Further improvement in the three electrode array performance by using a fourth “multiple ionophore electrode” (MIE) is discussed. Results obtained are compared with single electrode dip and FIA measurements of sodium in plasma samples.