Punching techniques

Another evident trend is the application of mechanical computers for the rapid calculation of distillation problems. At least two papers have already appeared, one by Weil (57) on the use of an electronic computer, and the other by Rose and Williams (47) on the application of the IBM card punch technique. If a short rigorous method is not forthcoming, machine calculations may be the answer to accurate design of fractionating equipment. 

Matthew JK, Virginia AD (2009) Viscoelasticity and shear stability of single-walled caibon nanotube/unsaturated polyester resin dispersions. Macromolecules 42(17) 6624—6632 Mehta H, Wangshul H, Kanagaraj S (2011) Studies on mechanical properties of carbon nanotubes/ high-density polyethylene nanocomposites by small punch technique. Int J Nanosci 10(1-2) 247-251... 

Some ductile plastics, such as PC and ABS, can be fabricated like metals with punching and cold-forming techniques. These processing techniques are analogous to the hardness tests in that a rigid indentor is pressed into a sheet of a less-rigid plastic. 

Since these studies utilized autoradiographic techniques, it was important to determine the chemical nature of the material measured using radiochemical procedures. Using punch biopsies of the brain slices which were measured autoradiographically, it was shown using thin-layer chromatography that about 30% of the radioactivity was associated with unchanged BCNU (14). It was therefore concluded that the measurements described above accurately reflect brain concentrations of BCNU. 

Sampling techniques must be defined and controlled. If leaf punch samples are taken, the sampling design must define the portions of the crop that will be sampled (e.g., all sides of each plant, how high to sample in trees, inner and outer leaves). Never sample a leaf by brushing with an outer leaf that may be sampled at a later date. 

The regulations require three samples from the treated plot (one from each subplot) and a single sample from the control plot at each sampling interval. For foliage the preferred technique is to collect leaf punch samples. Leaf punch samplers are available in 5-, 2.5- and 1.25-cm punch areas. Common practice requires a sample of 40-5-cm leaf disks to provide a 400-cm sample using both the top and bottom of the leaf disk to calculate sample surface area. 

For tree crops, the EPA recommends the Iwata approach. In this approach, 40 punches are collected for each sample at various heights and at 45° intervals around the circumference of each sampled tree. The sampling design and technique are described below. 

Booster was used to initiate the expl at one end. The radial motion of the cylinder wall was measured in a plane perpendicular to the cylinder axis 7 inches from the booster end, A streak camera recorded the motion, using conventional shadowgraph technique (See under CAMERAS, HIGH-SPEED PHOTOGRAPHIC in Vol 2 of Encycl, p CI3-L). In addn, the deton velocity of the expl was measured by placing pin switches 9-i° apart on the surface of the cylinder, as described, for example, by Cook (Ref 2, p 29). The streak camera record was read on a precision comparator which punched out the data directly on IBM cards. A computer code con-... 

The invention of punch-card technique was done in 1890 by Herman Hollerith at the US Bureau of Census and used at first for adding up the number of inhabitants in US each tenth year. The technique was greatly expanded beginning in the 1930 s and many scientific applications of punched-card equipment have been found as a computing aid. 

Although pellets for exptl use are loaded by single operation methods in which weighed charges are pressed either by stop loading or by controlled pressure techniques, quantity production of pellets is accomplished in automatic pelleting machinery, in which the explosive is metered volumetrically by the controlled movements of punches. Single stroke presses of the types used for expls produce about 90 pellets per minute while rotary presses have rates of about 700 pellets per minute... 

Figure 5 shows the results of the authors study on the ability of NIR to monitor the scale-up from the laboratory Carver Press to the Fitzpatrick roller compactor. Because the NIR signal is influenced by changes in the physical and mechanical properties, multivariate data analysis techniques were used to identify and separate these contributions in the overall NIR signal. A flat-faced rectangular die and punch set, 40 x 15 mm in size, was fitted on the laboratory Carver Press to prepare tablets similar in shape and size to the roller compacted samples. 

The patients verbal reports were transferred to IBM punch cards and are being submitted to several techniques of linguistic analysis. One such technique, the Role Construct Sorting Procedure, is a test to measure changes in the way patients conceptualize people who are important in their lives. More-... 

The optimal moisture content of the dried granulation needs to be determined. High moisture content can result in (1) tablet picking or sticking to tablet punch surfaces and (2) poor chemical stability as a result of hydrolysis. An overdried granulation could result in poor hardness and friability. Moisture content analysis can he performed using the conventional loss-on-drying techniques or such state-of-the-art techniques as near infrared (NIR) spectroscopy. 

Pickering and Eckstrom evaporate catalyst metals, such as rhodium or nickel, onto the mirrors of a White multiple (20-40) reflection cell (68). A series of scans are taken before and after adsorption of the gases. The comparison of the two sets of curves is accomplished by a method described by King et al. (69), in which the detector output is fed to an ana-log-to-digital converter for recording on punched cards. The final graphs are plotted with an IBM accounting machine. This technique makes it possible to study absorption bands of the order of 0.03 to 0.05% of the radiation. 

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