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Crucial products

The technical functionality of chemical prodncts is the crucial product quality in B2B markets. Here especially trouble-free operating cycles and the minimisation of warranty risks play a decisive role. Enviromnental and health-related product qualities can only become significant for the market in places where the technical functionality is ensured and also sensitised customers or employees are available or where companies take action to secnre against scandals and create an image. The additional qualities become relevant especially on demand-dominated, dynamic markets with short product cycles and differentiated quality production. However, on stable mass markets with Fordist structures even minimum price increases or quality changes may prevent innovations or at least delay them for a long time. [Pg.104]

For example, the particle size distribution in emulsion, suspension, and precipitation polymerization can be a crucial product specification. One of the greatest difficulties in achieving quality control of the polymer product is that the actual customer specifications may be in terms of non-molecular parameters such as tensile strength, crack resistance, temperature stability, color or clarity, absorption capacity for plasticizer, etc. [Pg.115]

As mentioned above, the capacity of the intermediate iminium ion (2) to condense with its counterion is a crucial product-determining step. This is illustrated by the reaction of trimethylamine A -oxide with acetic and trifluoroacetic anhydride (Scheme 2). With acetic anhydride the iV-demethylated product di-methylacetamide is formed in high yield, whereas with trifluoroacetic anhydride under similar conditions the iminium ion (9), a synthetically useful Mannich reagent, is generated in nearly quantitative yield. ... [Pg.912]

The tetrahedral intermediate formed on the enzyme but not covalently linked - can be removed by a rapid alkaline quench and its constitution and spontaneous decomposition studied. It decomposes by loss of phosphate to give an ion pair. Rate-determining and product-determining steps are different, with a crucial product-determining ionisation not apparent in the kinetics. The intermediate ion can lose a proton, add 04 of the sugar or add water and revert to pyruvate, in processes governed by the second ionisation of the phosphate, although this is not seen in the pH-rate profile. [Pg.546]

Seven-membered cyclic orthocarbonates are also available via a formal double Baeyer-Villiger reaction by oxidation of a cyclopentanone diethyl acetal with m-chloroperbenzoic acid, for example the synthesis of orthocarbonates (167) and (168) (Scheme 31) <82JAI769>. However, only moderate yields (15-37%) of pure seven-membered cyclic orthocarbonates have been obtained, as complications arise with the separation of the complex reaction mixture. Moreover, precautions should be taken, because these reactions become very violent after an induction period. However, this procedure provides a simple method for the oxidative removal of the carbonyl group from a ketone via the intermediacity of an orthocarbonate. This is accomplished by treatment of the crude reaction mixture with LAH in ethereal solution to give the corresponding diols, thereby avoiding the crucial product separation. [Pg.259]

Mohammed asserts oxen are the crucial productive asset that would liberate me from this insecurity trap. On the other hand, however, he does not want to take credit from a regional credit organization to buy an ox as he does not want to be indebted and fears that the debt may be passed on to his children If he falls to repay. [Pg.18]

One of the crucial product usage parameters is the consumer s satisfaction, which requires a manufacturer to create a high-quality, safe, and reliable product. Based on this, designing for safety is a systematic and methodical activity and utilizes a variety of standardized procedures in the process of creating a final product with partial objectives and the final objective being taken into account. [Pg.142]

The contractor is paid per foot drilled. Whilst this will provide an incentive to make hole quickly, the same risks are involved as in the turnkey contract. Footage contracts are often used for the section above the prospective reservoir where hole conditions are less crucial from an evaluation or production point of view. [Pg.62]

Introduction and Commercial Application The reservoir and well behaviour under dynamic conditions are key parameters in determining what fraction of the hydrocarbons initially in place will be produced to surface over the lifetime of the field, at what rates they will be produced, and which unwanted fluids such as water are also produced. This behaviour will therefore dictate the revenue stream which the development will generate through sales of the hydrocarbons. The reservoir and well performance are linked to the surface development plan, and cannot be considered in isolation different subsurface development plans will demand different surface facilities. The prediction of reservoir and well behaviour are therefore crucial components of field development planning, as well as playing a major role in reservoir management during production. [Pg.183]

The lack of correlation between the flucUiating stress tensor and the flucUiating heat flux in the third expression is an example of the Curie principle for the fluctuations. These equations for flucUiating hydrodynamics are arrived at by a procedure very similar to that exliibited in the preceding section for difllisioii. A crucial ingredient is the equation for entropy production in a fluid... [Pg.706]

For an isotropic material, all orientations are equally probable and all such products that have an odd number of Tike direction cosines will vanish upon averaging-. This restricts the nonvanishing tensor elements to those such as xVaaa abba - Similarly for the elements Such orientational averaging is crucial in... [Pg.1190]

In the alkylative cyclization of the 1,6-enyne 372 with vinyl bromide, formation of both the five-membered ring 373 by exn mode carbopalladation and isomerization of the double bonds and the six-membered ring 374 by endo mode carbopalladation are observed[269]. Their ratio depends on the catalytic species. Also, the cyclization of the 1,6-enyne 375 with /i-bromostyrene (376) affords the endo product 377. The exo mode cyclization is commonly observed in many cases, and there are two possible mechanistic explanations for that observed in these examples. One is direct endo mode carbopalladation. The other is the exo mode carbopalladation to give 378 followed by cyclopropana-tion to form 379, and the subsequent cyclopropylcarbinyl-homoallyl rearrangement affords the six-membered ring 380. Careful determination of the E or Z structure of the double bond in the cyclized product 380 is crucial for the mechanistic discussion. [Pg.180]

The Fischer cyclization has proved to be a very versatile reaction which can tolerate a variety of substituents at the 2- and 3-positions and on the aromatic ring. An extensive review and compilation of examples was published several years ago[3]. From a practical point of view, the crucial reaction parameter is often the choice of the appropriate reaction medium. For hydrazones of unsymmetrical ketones, which can lead to two regioisomeric products, the choice of reaction conditions may determine the product composition. [Pg.54]

In the use of temperature measurement for control of the separation in a distillation column, repeatability is crucial but accuracy is not. Composition control for the overhead product would be based on a measurement of the temperature on one of the trays in the rectifying section. A target would be provided for this temperature. However, at periodic intervals, a sample of the overhead product is analyzed in the laboratory and the information provided to the process operator. Should this analysis be outside acceptable limits, the operator would adjust the set point for the temperature. This procedure effectively compensates for an inaccurate temperature measurement however, the success of this approach requires good repeatability from the temperature measurement. [Pg.758]

Ereduc tion of a product or service must be evaluated over its entire istoiy or life cycle. This life-cycle analysis or total systems approach (Ref. 3) is crucial to identifying opportunities for improvement. As described earher, this type of evaluation identifies energy use, material inputs, and wastes generated during a products hfe from extraction and processing of raw materials to manufacture and transport of a product to the marketplace and finally to use and dispose of the produc t (Ref. 5). [Pg.2165]

Micro-scaling or bottom up approach to quality costs, where it is possible to calculate the cost of losses involved in manufacture and due to returns and/or claims. This method requires a great deal of experience and relies on the availability of detailed cost data throughout a product s life-cycle. While this is a crucial activity for a business, it is also not a practical approach for estimating the quality cost for product in the early stages of product development. [Pg.14]

A proposed product development process that facilitates designing capable and reliable products has been outlined above. It must be stressed that the product development process itself will not produce quality products, and consideration of many issues are crucial to success, such as company strategy, management structure, commitment, sufficient resources, communication, and most importantly proficient engineering practices, such as the following. [Pg.268]

Thermoplastic elastomers have now been available for over 30 years and the writer recalls organising a conference on these materials in 1969. In spite of considerable publicity since that time these materials still only comprise about 5-10% of the rubber market (equivalent to about 1-2% of total plastics consumption). It is important to appreciate that simply being a thermoplastic material (and hence being processed and reprocessed like a thermoplastic plastics material) is not enough to ensure widespread application. Crucially the material must have acceptable properties for a potential end-use and at a finished product price advantageous over other materials. [Pg.880]

The upshot of all this research since 1954 is rather modest, with the exception of the GE research, which indicates that techniques and individual materials have to be married up an approach which is crucial for one material may not be very productive for another. This is of course not to say that this 40-year programme of research was wasted. The initial presumption of the potential value of ultra-pure metals was reasonable it is the obverse of the well-established principle that minor impurities and dopants can have major effects on the properties of metals. [Pg.358]

My principal objective in Section 10.4 has been to underline the necessity for a drastic enhancement of a crucial experimental technology, the production of ultrahigh vacuum, as a precondition for the emergence of a new branch of science, and this enhancement was surveyed in the preceding Section. It would not be appropriate in this book to present a detailed account of surface science as it has developed, so 1 shall restrict myself to a few comments. The field has been neatly subdivided among chemists, physicists and materials scientists it is an ideal specimen of the kind of study which has flourished under the conditions of the interdisciplinary materials laboratories described in Chapter 1. [Pg.407]

Because the rates of chemical reactions are controlled by the free energy of the transition state, information about the stmcture of transition states is crucial to understanding reaction mechanism. However, because transition states have only transitory existence, it is not possible to make experimental measurements that provide direct information about their structure.. Hammond has discussed the circumstances under which it is valid to relate transition-state stmcture to the stmcture of reactants, intermediates, and products. His statements concerning transition-state stmcture are known as Hammond s postulate. Discussing individual steps in a reaction mechanism, Hammond s postulate states if two states, as, for example, a transition state and an unstable intermediate, occur consecutively during a reaction process and have neariy the same energy content, their interconversion will involve only a small reorganization of molecular stmcture. ... [Pg.217]

Adhesives and resins are one of the most important raw materials in wood-based panels. Thus, each question concerning the life cycle assessment and the recycling of bonded wood panels does bring into question the adhesive resins used. This includes, for example, the impact of the resin on various environmental aspects such as waste water and effluents, emission of noxious volatile chemicals during production and from the finished boards, or the reuse for energy generation of wood panels. The type of resin has also a crucial influence on feasibility and efficiency for several material recycling processes. [Pg.1043]


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See also in sourсe #XX -- [ Pg.2625 ]




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