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Leveling with additives

The best way to accomplish this is to prepare standards in the usual way—add increasing volumes of a standard analyte solution to a series of volumetric flasks (include zero added)—but also add a volume of the sample solution to each before diluting to the mark with solvent. Thus you would have a series of standards in which the concentration of analyte added would be known, the smallest concentration added being zero. Exactly how much sample solution is used and what concentration added values would be prepared would be dictated by what concentration levels, with additions, would produce a linear standard curve. In any case, a diluted sample matrix is present in each standard and the matrices are matched. A disadvantage is that it is impossible to prepare a blank with a matched matrix. Thus, a pure solvent blank, or other approximation, must be used. [Pg.257]

The training program also includes a provision for timely feedback of new measurements of exposure levels, with additional control information where needed. [Pg.309]

An important task for theory in the quest for experimental verification of N4 is to provide spectral characteristics that allow its detection. The early computational studies focused on the use of infrared (IR) spectroscopy for the detection process. Unfortunately, due to the high symmetry of N4(7)/) (1), the IR spectrum has only one line of weak intensity [37], Still, this single transition could be used for detection pending that isotopic labeling is employed. Lee and Martin has recently published a very accurate quartic force field of 1, which has allowed the prediction of both absolute frequencies and isotopic shifts that can directly be used for assignment of experimental spectra (see Table 1.) [16]. The force field was computed at the CCSD(T)/cc-pVQZ level with additional corrections for core-correlation effects. The IR-spectrum of N4(T>2 ) (3) consists of two lines, which both have very low intensities [37], To our knowledge, high level calculations of the vibrational frequencies have so far only been performed... [Pg.433]

Consistent with the rationale for developing PPARa/y dual agonists, combining PPAR8 and PPARy agonist activity could result in a therapy that has the expected benefits on glucose levels with additional positive effects on lipid abnormalities commonly seen in individuals with T2D and the metabolic syndrome. [Pg.379]

Recent advances in motion-capture technology combined with continued developments in small-scale electronics can enable the rapid design and evaluation of flight vehicle concepts (Troy et al, 2007). These evaluations can be extended to the mission level with additional vehicles and associated software. [Pg.105]

Note 4—For some samples, it is necessary to heat and stir until the sample is completely homogeneous. Maintain the liquid level with additional TCE during heating if necessary. [Pg.725]

In addition to the possible multipolarities discussed in the previous sections, internal-conversion electrons can be produced by an EO transition, in which no spin is carried off by the transition. Because the y-rays must carry off at least one unit of angular momentum, or spin, there are no y-rays associated with an EO transition, and the corresponding internal-conversion coefficients are infinite. The most common EO transitions are between levels with J = = where the other multipolarities caimot contribute. However, EO transitions can also occur mixed with other multipolarities whenever... [Pg.454]

Analysis and Specifications. Typical product analyses include sohds level, ash, color, conductivity, purity, and minor saccharide levels (19). Specifications for anhydrous and monohydrate crystalline dextrose are available (15). High quahty anhydrous dextrose produced for the pharmaceutical industry is prepared in accordance with additional specifications (20). [Pg.292]

A comparison of actual with budgeted results can be used as the basis for control at the company, departmental, plant, or project level. In addition, a continuing record of performance should be maintained to provide the data for the preparation of further budgets. [Pg.852]

Cropley made general recommendations to develop kinetic models for compUcated rate expressions. His approach includes first formulating a hyperbolic non-linear model in dimensionless form by linear statistical methods. This way, essential terms are identified and others are rejected, to reduce the number of unknown parameters. Only toward the end when model is reduced to the essential parts is non-linear estimation of parameters involved. His ten steps are summarized below. Their basis is a set of rate data measured in a recycle reactor using a sixteen experiment fractional factorial experimental design at two levels in five variables, with additional three repeated centerpoints. To these are added two outlier... [Pg.140]

Although the diffusion mechanism can be seen as mechanical but occurring at molecular dimensions, van der Waals intermolecular interactions and conformational entropic energy provide an additional mechanism that increases adhesion [62]. It is interesting to note the analogy that exists between this mechanism at the molecular level with the adherence, adhesion and viscoelastic deformations concept applied for a macroscopic adhesive. [Pg.696]

Therefore if the level of slurry is maintained eonstant with addition of fresh feed, then the pressure drop due to the drag in the liquid flowing through the eake ean be equated to the pressure drop due to eentrifugal aetion viz. from equations 4.84 and 4.85... [Pg.113]

The initial aim of the procedure is to generate a reasonable base case design that can be used for preliminary economic evaluation of the process. This can subsequently be optimized and/or compared with any process alternatives that are identified. The complete process is always considered at each decision level, but additional fine detail is added to the structure of the flowsheet at any stage. Established heuristics and equipment selection procedures are used together with new process synthesis insights to guide each flowsheet decision. [Pg.271]

The piping around any facility, other than the straight pipe connecting the equipment, is made up primarily of a series of control stations. Flow from one vessel goes through a control station and into a piece of pipe that goe.s to another vessel. In addition to considering the use of block valves, check valves, etc., all control stations should be designed so that the control valve can be removed and any bypass valve is located above or on a level with the main control valve. If the bypass is below the con tiol valve, it provides a dead space for water accumulation and corrosion. [Pg.466]

Uncertainty on tlie other hand, represents lack of knowledge about factors such as adverse effects or contaminant levels which may be reduced with additional study. Generally, risk assessments carry several categories of uncertainly, and each merits consideration. Measurement micertainty refers to tlie usual eiTor tliat accompanies scientific measurements—standard statistical teclmiques can often be used to express measurement micertainty. A substantial aniomit of uncertainty is often inlierent in enviromiiental sampling, and assessments should address tliese micertainties. There are likewise uncertainties associated with tlie use of scientific models, e.g., dose-response models, and models of environmental fate and transport. Evaluation of model uncertainty would consider tlie scientific basis for the model and available empirical validation. [Pg.406]

If the operator removes the rotor from the balancing shaft without marking the point of bore and shaft contact, it may not be in the same position when reassembled. This often shifts the rotor by several mils as compared to the axis on which it was balanced, thus causing an imbalance to be introduced. The vibrations that result are usually enough to spoil what should have been a precision balance and produce a barely acceptable vibration level. In addition, if the resultant vibration is resonant with some part of the machine or structure, a more serious vibration could result. [Pg.936]

With still further increase in concentration this process continues. In addition, we may mention that, although in the solutions discussed the H20 molecules outnumber the (H30)+ ions nearly ten to one, in the still more concentrated solutions the HaO molecules become more and more sparse. For indicators 6 to 17 the same stepwise procedure was followed in mixtures of H2SO4 and water and yielded progressively higher proton levels. With the last indicator, No. 17, measurements were made in mixtures containing from 96 to 100 per cent of H2SO4. In the 100 per cent H2SO4 the proton transfer presumably was... [Pg.247]

Basicity also may be regarded as a measure of amine hydrolysis, and it governs the increase in pH level, per additional unit measure of amine. The law of diminishing returns applies of course, and beyond a certain point there is little further increase in system pH. Also, the basicity constant for individual amines varies considerably with temperature, so it is important to consider Kb at the relevant operating temperature, rather than simply at ambient temperature. [Pg.525]

The search for the racemic form of 15, prepared by allylic cyclopropanation of farnesyl diazoacetate 14, prompted the use of Rh2(OAc)4 for this process. But, instead of 15, addition occurred to the terminal double bond exclusively and in high yield (Eq. 6) [65]. This example initiated studies that have demonstrated the generality of the process [66-68] and its suitability for asymmetric cyclopropanation [69]. Since carbon-hydrogen insertion is in competition with addition, only the most reactive carboxamidate-ligated catalysts effect macrocyclic cyclopropanation [70] (Eq. 7), and CuPF6/bis-oxazoline 28 generally produces the highest level of enantiocontrol. [Pg.212]

Many of the earlier studies of mass transfer involved measuring the rate of vaporisation of liquids by passing a turbulent air stream over a liquid surface. In addition, some investigations have been carried out in the absence of air flow, under what have been termed still air conditions. Most of these experiments have been carried out in some form of wind tunnel where the rate of flow of air and its temperature and humidity could be controlled and measured. In these experiments it was found to be important to keep the surface of the liquid level with the rim of the pan in order to avoid the generation of eddies at the leading edge. [Pg.649]


See other pages where Leveling with additives is mentioned: [Pg.36]    [Pg.731]    [Pg.15]    [Pg.36]    [Pg.731]    [Pg.15]    [Pg.67]    [Pg.91]    [Pg.174]    [Pg.378]    [Pg.536]    [Pg.3]    [Pg.232]    [Pg.454]    [Pg.170]    [Pg.372]    [Pg.460]    [Pg.334]    [Pg.371]    [Pg.639]    [Pg.157]    [Pg.355]    [Pg.308]    [Pg.892]    [Pg.1029]    [Pg.172]    [Pg.327]    [Pg.551]    [Pg.539]    [Pg.695]    [Pg.1145]    [Pg.1293]    [Pg.148]    [Pg.3]   
See also in sourсe #XX -- [ Pg.179 , Pg.190 , Pg.191 , Pg.192 ]




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Additives leveling

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