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The Scale

Hence these probes respond to solvent polarity qualitatively, and almost quantitatively, in the same way. It is now possible to set up a scale of solvent sensitivity, based on 1, in which the value of v(l), 3j, for cyclohexane is set equal to zero while that for dimethyl sulfoxide (DMSO) is set equal to 1.00, and values for all other solvents lying, by hypothesis, between these hmits. Parallel behavior is found for 3. The resulting values constitute the tt scale. [Pg.279]

If 2 or 4 is immersed in a solvent with proton acceptor properties, then instead of the resulting being almost coincident with that observed for 1 or 3, respectively, [Pg.279]

respectively [1]. As previously, cyclohexane was chosen to supply the lower value but this time hexamethylphosphoramide (HMPA) the upper one. The actual calculation process [6] is shghtly more sophisticated than this since it has to allow [Pg.279]

For example, 0 0° appears to be associated with AS, 0 0° with AH, and 0 0° with AG. Some values of 0 for various basicity-related processes are assembled in Table 11.1. The disconcerting discovery to which this analysis has led is that, while the 4-nitroaniline p scale appears closely similar in its sensitivity to the solute scales shown in juxtaposition to it, that of 4-nitrophenol is not [3, 6]. Hence the latter probe is unsuitable for generating a solvent scale that aims to be compatible with the galaxy of - closely correlated - solute scales. As Abraham et al. [6] emphasize this is most unfortunate, because the absorption peaks of p-nitrophenol are technically by far the best to use, being more Gaussian in shape and possessing less fine structure. In the event, these authors [6] based their solvent P scale, P-, entirely on aniline-type indicators. [Pg.280]

However, they do not speculate on how this difference arises. One possible explanation starts from the distinction between nitrogen, with one lone pair, and oxygen. [Pg.280]


Figure 3.45 H NMR spectrum of trani-Pt(PEl3)2HCl in benzene solution. The t scale can be converted to the 6 scale now used by the relationship b = 10 - t. (Reproduced with permission from Proc. Chem. Soc.. 1962, 321.)... Figure 3.45 H NMR spectrum of trani-Pt(PEl3)2HCl in benzene solution. The t scale can be converted to the 6 scale now used by the relationship b = 10 - t. (Reproduced with permission from Proc. Chem. Soc.. 1962, 321.)...
Kamlet MJ, Taft RW (1976) The solvatochromic comparison method. 1. The /6-scale of solvent hydrogen-bond acceptor (HBA) basicities. J Am Chem Soc 98 377-383. [Pg.481]

A iH NMR spectrum is a graph of resonance frequency (chemical shift) vs. the intensity of Rf absorption by the sample. The spectrum is usually calibrated in dimensionless units called "parts per million" (abbreviated to ppm) although the horizontal scale is a frequency scale, the units are converted to ppm so that the scale has the same numbers irrespective of the strength of the magnetic field in which the measurement was made. The scale in ppm, termed the 6 scale, is usually referenced to the resonance of some standard substance whose frequency is chosen as... [Pg.41]

For the majority of organic compounds, the chemical shift range for H covers approximately the range 0-10 ppm (from TMS) and for covers approximately the range 0-220 ppm (from TMS). By convention, the 6 scale runs (with increasing values) from right-to-left for H. [Pg.41]

The displacement of a signal from the hypothetical position of maximum shielding is called its chemical shift, notated as S (delta) and measured in parts per million (ppm). As indicated on Fig. 12-4, the zero of the 6 scale is conventionally located at the signal produced by the H s of tetramethylsilane (TMS), (CHj)4 Si. This compound serves because its H-signal is usually isolated in the extreme upheld region. Clues to the structure of an unknown compound can be obtained by comparing the chemical shifts of its spectrum to the d values in such tabulations as Table 12-3. Some generalizations about molecular structure and proton chemical shift in H nmr (pmr) arc ... [Pg.250]

The use of a secondary reference and/or employment of external referencing is a result of some practical considerations. Aspects considered range from principal factors like sample solubility, boiling point or signal overlap to trivial matters of convenience such as routine or tradition in a laboratory. In practice, the chemical shift S, measured relative to a secondary reference as an internal reference, is converted into the 6 scale according to the equation 2... [Pg.227]

A brief discussion of the various NMR parameters follows. The reader is referred to Stothers and other authors (8-12) for a detailed treatment of theoretical aspects. All chemical shifts listed in this review are given in the 6 scale relative to TMS (positive to lower field). [Pg.259]

Melting points were determined on a Yanako MP micro melting point apparatus and not corrected. IR spectra were measured on Jasco FT-IR 7000 spectrophotometer, UV spectra on Shimadzu UV-3000 spectrometer. H-NMR, C-NMR, H- C COSY and H- H COSY spectra were measured with a JNMGX270 spectrometer. Chemical shifts are given on the 6 scale with tetramethylsilane as an internal standard. MS was taken on a Hitachi M-6000 spectrometer. [Pg.287]

Because it is difficult to know to sufficient accuracy the value of the magnetic field applied (Harris, 1986), a standard of known resonance frequency is usually used. The most convenient standard for and proton NMR is tetramethylsilane (TMS) because it contains four equivalent carbon atoms, and the resultant strong signal means that only a small amount (1%-5%) need be added it gives rise to sharp signals, is chemically inert and is soluble in most organic materials (Kemp, 1986). The TMS peak is taken as 0 in the 6 scale and increases in a downfield direction. [Pg.327]

All boiling points and melting points are uncorrected. Capillary melting points were determined on a Thomas-Hoover melting point apparatus. Infrared were determined with perkin-Elmer Model 377 spectrophotometer. NMR spectra were obtained on a Varian T-60 spectrometer. Chemical shifts are reported on the 6 scale. Gel permeation chromatography measurements were performed using Altex pump, Sp 8200 UV detector and Styragel lO A, lO X columns. [Pg.311]

Note that the solvent in which the NMR sample is dissolved is reported (here deuteriochloroform) and the chemical shift is reported in parts per million relative to TMS (the 6 scale). Where it is appropriate, the coupling constants are reported (J). Only key peaks from the IR are reported as well as key ions from the mass spectrum. The mass spectrum is reported as two numbers (1) the m/s and (2) the relative intensity. For the exact mass (HRMS), the formula and mass for the expected formula are given, along with the actual mass found in the experiment. [Pg.700]

Similar principles to Problem 7 but easier. Note that the formula to be proved is to be applicable to any substance, not necessarily a gas. The only purpose of the gas, in the question as it is expressed, is to define the 6 scale of temperature. [Pg.463]

Now cascade any surplus heat down the temperature scale from interval to interval. This is possible because any excess heat available from the hot streams in an interval is hot enough to supply a deficit in the cold streams in the next interval down. Figure 6.18 shows the cascade for the problem. First, assume that no heat is supplied to the first interval from a hot utility (Fig. 6.18a). The first interval has a surplus of 1.5 MW, which is cascaded to the next interval. This second interval has a deficit of 6 MW, which reduces the heat cascaded from this interval to -4.5 MW. In the third interval the process has a surplus of 1 MW, which leaves -3.5 MW to be cascaded to the next interval, and so on. [Pg.178]

Looking at the heat flows in Fig. 6.18a, some are negative, which is infeasible. Heat cannot be transferred up the temperature scale. To... [Pg.178]

Fig. XI-6. Polymer segment volume fraction profiles for N = 10, = 0-5, and Xi = 1, on a semilogarithinic plot against distance from the surface scaled on the polymer radius of gyration showing contributions from loops and tails. The inset shows the overall profile on a linear scale, from Ref. 65. Fig. XI-6. Polymer segment volume fraction profiles for N = 10, = 0-5, and Xi = 1, on a semilogarithinic plot against distance from the surface scaled on the polymer radius of gyration showing contributions from loops and tails. The inset shows the overall profile on a linear scale, from Ref. 65.
X. Experimentally, it was found tliat x A , witli 3.2 < v < 3.6. The viscosity scales also as cc Ain contrast to tire situation below M, where x A. It is also interesting to compare tire dependence of tire diffusion... [Pg.2529]

For these sequences the value of Gj, is less than a certain small value g. For such sequences the folding occurs directly from the ensemble of unfolded states to the NBA. The free energy surface is dominated by the NBA (or a funnel) and the volume associated with NBA is very large. The partition factor <6 is near unify so that these sequences reach the native state by two-state kinetics. The amplitudes in (C2.5.7) are nearly zero. There are no intennediates in the pathways from the denatured state to the native state. Fast folders reach the native state by a nucleation-collapse mechanism which means that once a certain number of contacts (folding nuclei) are fonned then the native state is reached very rapidly [25, 26]. The time scale for reaching the native state for fast folders (which are nonnally associated with those sequences for which topological fmstration is minimal) is found to be... [Pg.2657]

In Eqs. (5) and (6), M is the total mass of the nuclei and is the mass of one electron. By using Eq. (2), the system s internal kinetic energy operator is given in terms of the mass-scaled Jacobi vectors by... [Pg.183]

Figure 6. Bending potential curves for the X Ai, A B electronic system of BH2 [33,34], Full hotizontal lines K —Q vibronic levels dashed lines /f — I levels dash-dotted lines K — 2 levels dotted lines K — 3 levels. Vibronic levels of the lower electronic state are assigned in benf notation, those of the upper state in linear notation (see text). Zero on the energy scale corresponds to the energy of the lowest vibronic level. Figure 6. Bending potential curves for the X Ai, A B electronic system of BH2 [33,34], Full hotizontal lines K —Q vibronic levels dashed lines /f — I levels dash-dotted lines K — 2 levels dotted lines K — 3 levels. Vibronic levels of the lower electronic state are assigned in benf notation, those of the upper state in linear notation (see text). Zero on the energy scale corresponds to the energy of the lowest vibronic level.
Two convenient forms of bath are shown ui Fig. 11,10, 2, a and 6. The former consists of a long-necked, round-bottomed flask (a longnecked Kjeldahl flask of 100 ml. capacity is quite satisfactory) supported by means of a clamp near the upper part of the neck. The thermometer is fltted through a cork, a section of the cork being cut away (see inset) so that the thermometer scale is visible and also to allow free expansion of the air in the apparatus. The bulb is about three-quarters filled with... [Pg.77]


See other pages where The Scale is mentioned: [Pg.391]    [Pg.227]    [Pg.73]    [Pg.791]    [Pg.463]    [Pg.101]    [Pg.298]    [Pg.126]    [Pg.488]    [Pg.391]    [Pg.227]    [Pg.73]    [Pg.791]    [Pg.463]    [Pg.101]    [Pg.298]    [Pg.126]    [Pg.488]    [Pg.242]    [Pg.233]    [Pg.247]    [Pg.832]    [Pg.855]    [Pg.857]    [Pg.910]    [Pg.1941]    [Pg.2361]    [Pg.2370]    [Pg.2374]    [Pg.2382]    [Pg.435]    [Pg.190]    [Pg.195]    [Pg.210]    [Pg.430]    [Pg.466]   


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Absolute zero and the Kelvin scale

Advanced Expression of Biopharmaceuticals in Yeast at Industrial Scale The Insulin Success Story

Application of the Scaled Particle Theory

Applications of the pure SPP, SA and SB scales

Aspects Concerning the Scale-up

At the Industrial Scale

At the Laboratory Scale

Atomic level energy and the scale of electromagnetic waves

Atomic-Scale Structure of the Cobalt-Promoted Catalyst

Atomistic scale models at the catalyst surface

Autoionization of Water and the pH Scale

Biocatalytic Approaches for the Large-Scale Production of Asymmetric Synthons

Bridging the Length Scales

CHOICE OF THE TIME SCALING FACTOR

Calibration of the Time Scale

Calibration of the wavelength scale

Challenges in the Design and Development of Large-Scale Photocatalytic Reactors for Water Purification

Choice of the renormalized length scale

Combining Scale and Ecological Dynamics The Hierarchical Patch Dynamic Paradigm

Comments on the Use of Simulation for Scale-up and Reactor Performance Studies

Concentration, the pH Scale, and Indicators

Confirmatory tests for anions on the semimicro scale

Control in the slow time scale

Conversion of Temperatures from the and 1968 Scales to ITS

Definition and Properties of the Absolute Potential Scale in Solid Electrochemistry

Definition of the BF3 Affinity Scale

Definition of the Donor Number Scale

Definition of the Scale

Dimensional Scaling Factors for the Mass Transfer Rate Processes

Dispersion modelling over the outer-scale

Dynamic Scaling-The Alaskan Pipeline

Economy of Scale and the Six-Tenths Factor

Electroanalysis at the micro-and nano-length scale

Electrochemical Processes at the Micro and Nano Scale

Electrodeposition on the Nanometer Scale In Situ Scanning Tunneling Microscopy

Electronegativity the spectroscopic scale

Elements of the scaled particle theory

Equilibrium constants expressed on the molality and volume concentration scales

Estimating Emissions at the Regional Scale

Evidence of the Interfacial Parameter Scale

Example 3 Scaling up the System Application to Industrial Production

Experimental Demonstration of the Novel Process Concept in a Pilot-Scale Set-Up

Experimental Establishment of the Absolute Potential Scale

Experimental tests of the scaling law predictions

Extending Atomistic Time Scale Simulations by Optimization of the Action

Extending the Time Scale Path Methodologies

Extending the Time Scale in Atomically Detailed Simulations

Flow Phenomena on the Micro Scale

Geophysical evidence for the scale of mantle convection

Good Laboratory Practice (GLP) regulations and their impact on the small-scale processing procedures

Governing Equations in the Macro Scale

Governing Equations on the Micro Scale

Hartree-Fock level in the context of local-scaling transformations

Health of the Nation Outcome Scales

Hyperbolic Scaling and Hamilton-Jacobi Equation for the Front Position

Identification of Group V cations on the semimicro scale

Industrial rates and the scale-down problem

Information at the Microscopic Scale

Laboratory-scale processing of the recycled material

Large Scale Orientation - The Need for a Finite Strain Tensor

Large-Scale Cl and the Unitary-Group Approach

Large-Scale Preparation of the Supported Metallocene Catalysts

Large-scale Detection of Genetic Variation The Key to Personalized Medicine

Large-scale Production of the M6L4 Complex

Large-scale-features of the human gene landscape

Linear scaling of the energy

Local-scaling transformation of the

Manipulation at the Micron Scale

Measurement of drying rate in the production scale dryer

Mechanisms for the different scaling behaviour

Meteorology of the Local Scale

Microstructures as a Tool for Production in the Tons per Hour Scale

Modeling at the particle scale

Molarity and the pH Scale

New Approach to the Scale-Up Problem in Tumbling Blenders

Normalization on the Energy Scale

On more general copolymer models and the Brownian scaling

Optimization and Scale-Up of the DERA Reaction

Other small-scale fluctuations and their effects on the segmental motion

Overcoming the Scale-up Challenges

Path Properties The Scaling Limit

Pilot Plant Scale Studies for the Liquefaction of PVC Mixed Plastics

Practical Considerations in the Scale-Up of Powder-Filled Hard Shell Capsule Formulations

Preliminary tests on the semimicro scale

Preparation of solution for cation testing on the semimicro scale

Problems with Multiple Spatial Scales The Example of Plasticity

Process characteristic of the foam centrifuge and its scale-up

Quantification of the Concentration Scale

Quantification of the Depth Scale

Rate-Limiting Phenomena on the Industrial Scale

Reactions on the NMR Time Scale

Reduction based on the investigation of time-scales

Reference Points on the ITS-90 Temperature Scale

Referencing the Mass, Energy, and Intensity Scales

Scale Conformational Changes in the M, N, and O Intermediates

Scale-Up and Monitoring of the Wet Granulation Process

Scale-Up in the Field of Granulation and Drying

Scale-Up of the Compaction and Tableting Process

Scale-Up of the Conventional Fluidized Bed Spray Granulation Process

Scale-up of the homogenization process

Scale-up, Flow Distribution and Interface to the Macroscopic World

Scaled Particle Theory of the Isotropic-Nematic Transition

Scales of Bronsted Basicity and Affinity in the Gas Phase

Scaling Behavior of the Small Strain Modulus

Scaling Laws for the Critical Properties

Scaling Parameters for the Number MWD

Scaling analysis using the Mason number for ER fluids

Scaling and Convergence to the Diffusion Process

Scaling and the Dimensionless Parameters for Convective Heat Transfer

Scaling and the Renormalization Group

Scaling laws and the temperature blob model

Scaling laws in the dilute limit

Scaling of the Diffusion Equation

Scaling of the Reduced Liouville Equation

Scaling of the Zero-order Hamiltonian

Scaling of the descriptor variables

Scaling of the exponents

Scaling of the number MWD

Scaling of the parameters

Scaling the Cell Current

Scaling the Data

Scaling the von Smoluchowski Rate Law

Scaling-Up the Coating Process

Schematic representation of the relevant spatial scales in reactive distillation

Scheme for the Scale-up of Electrochemical Reactors

Selection of the pH scale

Self-Ionization of Water and the pH Scale

Separation and identification of Group IIB cations on the semimicro scale

Separation and identification of Group IIIA cations on the semimicro scale

Separation and identification of Group IIIB cations on the semimicro scale

Separation and identification of Group IV cations on the semimicro scale

Separation of cations into groups on the semimicro scale

Shear weak lensing as a probe of the large-scale structure

Silicon-based proposals: solution for the scaling

Simulation of the Bench-Scale Reactor

Simulation of the bench-scale unit

Sites on the Coarse-Grained Scale

Solvent acidity the SA scale

Solvent basicity the SB scale

Solvent polarity the SPP scale

Some typical operations on the semimicro scale

Special tests for mixtures of anions on the semimicro scale

Stage V. Process Scale-up The Moment of Truth

State of the Art in Theory and Modeling Multiple Scales

Surface Tension and the Scaled Particle Approach

Synoptic Scale Motion The General Circulation

Systematic analysis on the semimicro scale. General considerations

Temperatures from the 1948 and 1968 Scales to ITS

Tension Investigating the Microemulsion Model and Scaling

Testing for anions in solution on the semimicro scale

Testing the Entire Process on a Small Scale

The 4-Fluorophenol Affinity Scale

The 4-Fluorophenol Hydrogen-Bond Basicity Scale

The Absolute Scale of Temperature

The Application of DuPHOS Rhodium(l) Catalysts for Commercial Scale Asymmetric Hydrogenation

The Atomic-Scale Structure of a Ribosome

The BF3 Affinity Scale

The BF3 Affinity Scale Data

The Big Test Going to Plant Scale

The Centigrade Scale

The Chemical Shift Scale

The Computation of MCB and MCA Scales

The Corresponding Composition Scales

The Delta Scale

The Diiodine Affinity Scale

The Diiodine Basicity Scale

The Distance Scale

The Donor Number or SbCls Affinity Scale

The Dynamo Number and Scaling Relations

The Effect of Scale-up on Mass Transfer

The Formation of Scale

The Geologic Time Scale

The Geologic Time Scale and Gravimetric Analysis

The Geophysical Laboratory Temperature Scale

The Gordy Electronegativity Scale

The Gross Scale Averaged Two-Phase Transport Equations

The Ideal Gas Temperature Scale

The Importance and Scale of Fixed Bed Catalytic Processes

The International Nuclear Event Scale

The International Temperature Scale of

The Kolmogorov scale

The Large-Scale Biocatalytic Synthesis of Enantiopure Cyanohydrins

The Limits of Scale

The Mulliken Electronegativity Scale

The NMR Time Scale

The Probability Scale

The Py scale of Dong and Winnick

The S scale of Drago

The Scale of Carbon Sequestration

The Scale of Production

The Scale-Up Conundrum

The Scale-up of Real Batch Reactors

The Scaling Theory

The Scaling-up Process

The Thermodynamic Temperature Scale

The Z scale of Kosower

The a Scale

The acidity scale

The basic scaling law

The glass transformation on different time scales

The hydrogen scale

The length scales

The optimal scale combination (OSC) method

The p Scale

The pH Scale

The pH Scale A Way to Quantify Acidity and Basicity

The pH Scale Is Used to Describe Acidity

The pH and pOH Scales

The pH scale and acid strength

The pOH Scale

The problem of scale

The scale factor

The scale of Swain and Scott

The scale of nucleophilicity

The scale of operation

The scaling functions for purely electromagnetic interactions

The scaling limit

The scaling relations

The subjective weighting results in a numerical scale of RSDI

The thermodynamic scaling function

The time scales

The tt Scale

The two modeling scales

The use of molality and concentration scales

Time Scales of Mixing in the Atmosphere and Oceans

Two-stage Large-Scale Plants for the Processing of Bimodal Polyethylene

Uncertainty and the Question of Time Scale

Water and the pH Scale

Wetting Phenomena on the Nanometer Scale

What Is the Scaling Analysis

What are the best scales of amino acid attributes

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