Tolerance class

Tolerances the processing cost increases with the tolerance requirements. Not all dimensions are so easily controlled and one can distinguish three tolerance classes the tolerance also depends on the thicknesses ... 

Dimensions to Tolerance Class h7 for axially-split pumps, an additional tolerance of + 75 pm (0,003 In) to allow for gasket thickness. 

IClass A pipettes are manufactured to the highest tolerances. Class B pipettes have tolerances approximately twice that of Class A pipettes. 

Gene expression in late embryo development is tightly associated with desiccation tolerance. Classes of coordinately expressed mRNAs in plant embryos in vivo and under various culture conditions have been reported [24,70,73]. A few temporal programs that are unrelated to the variations in ABA concentrations can explain the expression patterns. These programs appear to be controlled by a maturation factor and a post-abscission factor... 

Ciystallograms of structure-type line diagrams have been developped by Smirnova (1971,1975a, b, 1976,1977) to recognise relations between structure types and homologous series based on structural elements. Tolerance classes of elements of a-Fe-, Cu-, Mg- and a-La-type are discussed by Smirnova, Kurashkovskaya and Below (1977 a, b, c) on the basis of miscibility properties. 

Thickness tolerance class This variable references the thickness tolerance as agreed between user and supplier (see Table 6.5). Classes A, B, and C refer to measurement by micrometer of the base material without cladding. Class D requires measurement by microsection (see Fig. 6.5). Classes K, L, and M refer to measurement by micrometer of the base material with the metal cladding. Class X refers to a requirement agreed upon between user and supplier. 

The combination of the hazard severity and the hazard probability defines the hazard risk classes. These classes are listed in Table 4 with different levels of tolerability Class A forms the intolerable area of the risk matrix, Class B and C the tolerable area and class D means acceptable risk. 

For class S-1 weights, two-thirds of the weights in a set must be within one-half of the individual tolerances given below. No group tolerances have been specified for class P weights. See Natl. Bur. Standards Circ. 547, sec. 1 (1954). 

Denomination Class M Class S Class S-1, individual tolerance, mg Class P, individual tolerance, mg... 

Table 1 is condensed from Handbook 44. It Hsts the number of divisions allowed for each class, eg, a Class III scale must have between 100 and 1,200 divisions. Also, for each class it Hsts the acceptance tolerances appHcable to test load ranges expressed in divisions (d) for example, for test loads from 0 to 5,000 d, a Class II scale has an acceptance tolerance of 0.5 d. The least ambiguous way to specify the accuracy for an industrial or retail scale is to specify an accuracy class and the number of divisions, eg. Class III, 5,000 divisions. It must be noted that this is not the same as 1 part in 5,000, which is another method commonly used to specify accuracy eg, a Class III 5,000 d scale is allowed a tolerance which varies from 0.5 d at zero to 2.5 d at 5,000 divisions. CaHbration curves are typically plotted as in Figure 12, which shows a typical 5,000-division Class III scale. The error tunnel (stepped lines, top and bottom) is defined by the acceptance tolerances Hsted in Table 1. The three caHbration curves belong to the same scale tested at three different temperatures. Performance must remain within the error tunnel under the combined effect of nonlinearity, hysteresis, and temperature effect on span. Other specifications, including those for temperature effect on zero, nonrepeatabiHty, shift error, and creep may be found in Handbook 44 (5). The acceptance tolerances in Table 1 apply to new or reconditioned equipment tested within 30 days of being put into service. After that, maintenance tolerances apply they ate twice the values Hsted in Table 1.

Table 1. Summary of Tolerances and Number of Divisions Applicable to Accuracy Classes ...

Regulation Outside the United States. Each country estabhshes its own weights and measures requirements. The majority of these are based on the recommendations of the Organisation Internationale de Miitrologie Liigale (OIML), ia Paris. K76-1 is the OIML equivalent of Handbook 44 it uses accuracy classes and an acceptance tolerance stmcture similar ia many ways to Table 1 (8). 

Therapeutics. Therapeutic materials represent a class of polypeptides that are a low volume, high value product. The production system need not be very efficient but the quaHty of the recombinant protein has to be extremely pure (33,34). Thus high cost mammalian production systems can be tolerated. However, some of the therapeutic proteins such as insulin, human growth hormone, interleukins, interferon, and streptokinase are produced microbially. 

SSRIs are well tolerated. Adverse effects for compounds in this class include nervousness, tremor, dizziness, headache, insomnia, sexual dysfunction, nausea, and diarrhea. In addition, the tricycHc antidepressant clomipramine (33), which is a potent nonselective serotonin reuptake inhibitor, is approved for treatment of obsessive—compulsive disorder. 

In the field of chemical sensors, the revolution in software and inexpensive hardware means that not only nonlinear chemical responses can be tolerated, but incomplete selectivity to a variety of chemical species can also be handled. Arrays of imperfectly selective sensors can be used in conjunction with pattern recognition algorithms to sort out classes of chemical compounds and thek concentrations when the latter are mixed together. 

Working-grade thermometers, conventionally called industrial resistance thermometers, are generally smaller than the SPRT element and may be as small as 2.5 mm in diameter and 10 mm in length. These are available in various 0°C resistances, eg, 100, 200, and 500 Q. They are available as unsheathed elements or in a wide variety of sheaths and enclosures, both standard and custom. They are relatively inexpensive. They are usually made to be interchangeable, without relying on iadividual cahbration, within limits of 0.25 K or closer upon special order. A typical tolerance statement for a precision-class industrial resistance thermometer is... 

In general, manufacturers do not report the cahbrations of iadividual sensors to the purchaser, except upon request, but instead pubUsh tables of resistance vs temperature and tolerance charts for each class. Deviation here means departure from a nominal set of values of resistance versus temperature given in a manufacturer s Hterature. 

Propranolol. Propranolol (Table 1), a Class II antiarrhythmic agent, is usefiil in the management of hypertrophic subaortic stenosis, especially for the treatment of exertional or other stress-induced angina by improving blood flow. The dmg can increase exercise tolerance in patients suffering from angina. Propranolol has been shown to have cardioprotective action in post-MI patients (37—39,98,99,108). 

Surface roughness to process risk FMEA Severity Rating, strength Ultimate tensile strength Uniaxial yield strength Bilateral tolerance Unilateral tolerance Tolerance to process risk Variance Class width... 

The other class of primary antioxidants are the phenols (hindered phenols, hindered bisphenols, hindered thiobisphenols, polyhydroxy phenols) (Fig. 34). Phenolic antioxidants are generally used when the discolouration of the amine antioxidants cannot be tolerated. Phenols may produce coloured reaction products (yellow, tan or pink) but the discolouration is significantly less than produced with amines. 

The low structural requirements for local anesthetic activity do not maintain in all classes of drugs. Structural requirements for biologic activity in fact follow a full continuum from those cases in which addition of a single carbon atom serves to abolish activity to the case of the local anesthetics that tolerate quite drastic alterations. 

A biopolymer produced by a particular strain of bacteria is becoming widely used as a substitute for clay in low-solids muds. Since the polymer is attacked readily by bacteria, a bactericide such as paraformaldehyde or a chlorinated phenol also must be used with the biopolymer. The system has more stable properties than the extended bentonite system, because biopolymer exhibits good rheological properties in its own right, and has a better tolerance to salt and calcium. The system can be formulated to include salt, such as potassium chloride. Such a system, however, would then be classed as a nondispersed inhibitive fluid. 

Moisture-cured urethanes These are the only paints in this class of materials that are single pack. The curing is provided by moisture from the atmosphere. This has the advantage that the material can tolerate a degree of dampness in the atmosphere and on the surface to be coated. Its disadvantage is that the film thickness per coat is limited and that, once opened, the entire container must be used immediately. Conversely, if the humidity is very low the cure may be lengthened or stopped. 

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