Short-cuts , allowable when

It is very important that you follow each of the steps listed below completely, in order do not try to take any short cuts. There are many modifications of this method. For example, a modification allows you to balance all the reactions as if they were in acidic solution followed by a step, when necessary, to convert to a basic solution. Switching to a modification before you completely understand this method very often leads to confusion, and an incorrect result. 

It is important to note that you did not enter the 10, nor did you enter the multiplication sign. If you experiment and enter the number into your calculator just as it is written, that is, 6.02 times 10 exponent 23, you will get an answer that is 10 times too big, or 6.02 x 1024. It is important that you realize that the calculator uses a short cut by showing 6.0223 when it really means 6.02 x 1023. Some tests allow you to use this shortcut, but it is always safe to use the true representation, which is the 10 with its proper exponent. 

GLP aims at a full reconstructability of any study conducted under its rules. Certain studies may be too limited in duration as to warrant the application of the Principles to the fullest extent. Feasibility considerations may lead to the view that certain pragmatic facilitations should be advisable. Nevertheless the spirit of the GLP Principles needs to be preserved, even when certain short-cuts may be allowed. Thus, the GLP Principles strive to lessen the burden of their (administrative) requirements for short-term studies to a certain degree without, however, jeopardising quality, integrity and reliability of these studies. 

A fully trained chemical operative will handle all chemicals with confidence in his personal safety, but he will never allow himself to become over confident, to take chances or short cuts. He knows that all chemicals must be treated with respect and, even when handling comparatively harmless materials, he will not deviate from proper handling methods since unsafe practices can easily become a habit, and bad habits are the hardest to break. 

A 2-1. three-necked flask is mounted on a steam bath and fitted with a reflux condenser, a separatory funnel, and an efficient sealed stirrer. In the flask is placed 600 cc. of absolute alcohol, and to this is added gradually 46 g. (2 gram atoms) of clean sodium cut into small pieces.1 The sodium ethoxide solution is stirred and cooled to room temperature, after which 267 g. (260 cc., 2.05 moles) of ethyl acetoacetate (Note 1) is added slowly through the separatory funnel. The reflux condenser is then replaced by a short still head, and the alcohol is removed by distillation at approximately room temperature and under the pressure of a water pump. When approximately half the alcohol has been removed, sufficient sodium enolate precipitates so that stirring has to be discontinued. When the residue appears dry (after about two hours) the last traces of alcohol are removed by heating for an hour on the steam bath under a pressure of 2 mm. The flask is allowed to cool to room temperature under reduced pressure. 

Indicator and sample selection are not the only choices a researcher has to make when using MAXCOV. A decision also has to be made about interval size, that is, how finely the input variable will be cut. Sometimes it is possible to use raw scores as intervals that is, each interval corresponds to one unit of raw score (e.g., the first interval includes cases that score one on anhedonia, the second interval includes cases that score two). This is what we used in the depression example. This approach usually works when indicators are fairly short and the sample size is very large, since it would allow for a sufficient number of cases with each raw score. In our opinion, this is the most defensible method of interval selection and should be used whenever possible. However, research data usually do not fit the requirements of this approach (e.g., the sample size is too small). Instead, the investigator can standardize indicators and make cuts at a fixed distance from each other (e.g.,. 25 SD), thereby producing intervals that encompass a few raw scores. 

The purpose of this book is to show how the consideration of molecular symmetry can cut short a lot of the work involved in the quantum mechanical treatment of molecules. Of course, all the problems we will be concerned with could be solved by brute force but the use of symmetry is both more expeditious and more elegant. For example, when we come to consider Huckel molecular orbital theory for the trivinylmethyl radical, we will find that if we take account of the molecule s symmetry, we can reduce the problem of solving a 7 x 7 determinantal equation to the much easier one of solving one 3x3 and two 2x2 determinantal equations and this leads to having one cubic and two quadratic equations rather than one seventh-order equation to solve. Symmetry will also allow us immediately to obtain useful qualitative information about the properties of molecules from which their structure can be predicted for example, we will be able to predict the differences in the infra-red and Baman spectra of methane and monodeuteromethane and thereby distinguish between them. 

When a parison is blown, a large volume of air must be displaced from the mold cavity in a short time. Because blowing is carried out at relatively low pressure, it is essential to provide venting to allow this air to escape without resistance. Unless a gloss finish is required on the molding, it is common practice to sandblast the cavity to a fine matt finish. This helps air to escape as the expanding parison touches the cavity face but it is not sufficient in itself. Vent slots may be cut at appropriate points into the mold parting face to a depth of 0.05 to 0.15 mm. The appropriate point is where there is a possibility for air to collect as the hot plastic expands in the cavity. 

Each time you mow, a freshly cut surface is available for pathogens to colonize. Repeated short mowing, under stressful conditions, makes plants smaller and fewer and allows weeds to easily move in. When plants are stressed by heat and drought in midsummer, it s best to raise the height of the blade and mow less frequently. 

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