Basic features weight

The electrical conductivity of a material is a macroscopic solid-state property since even in high molecular-weight polymers there is not just one conjugated chain which spans the distance between two electrodes. Then it is not valid to describe the conductivity by the electronic structure of a single chain only, because intra- and interchain charge transport are important. As with crystalline materials, some basic features of the microscopic charge-transport mechanism can be inferred from conductivity measurements [83]. The specific conductivity a can be measured as the resistance R of a piece of material with length d and cross section F within a closed electrical circuit,... 

In practice, binder system may consist of three or four additives that differ in their volatility and chemical decomposition. Furthermore, interactions between the binder and the particle surfaces may alter the decomposition kinetics of the pure polymer. In view of its complex nature, a detailed analysis of thermal debinding is not useful. Instead, we consider the basic features of the process for a simplified system consisting of a powder compact with a single binder [e.g., a high molecular weight thermoplastic polymer such as poly(methyl methacrylate), poly(propylene), or poly(vinyl butyral)]. 

Enzymes are high-molecular-weight protein molecules that catalyze reactions of importance in biology and biomedicine. Feature 29-1 discusses the basic features of enzymes. Enzymes are particularly useful as analytical reagents because of their selectivity. Consequently, they are widely used in the determination of molecules with which they combine when acting as catalysts. Such molecules are usually designated as substrates. In addition to the determination of substrates, enzyme-catalyzed reactions are employed for the determination of activators, inhibitors, and, of course, enzymes themselves. ... 

In the oldest and perhaps most commonly used method for measuring the adsorption of gases, a measured amount of gas is introduced to a known weight of an adsorbent. The amount adsorbed is calculated by comparing the resulting gas pressure with that which would be expected if no adsorption occurred. Many assemblies have been developed to fit specific adsorptions. They all require careful attention to a number of details for which reference should be made to the original publications.2,3,4 Only an outline of the basic features will be given here. 

Most neural networks are based on a model of a neuron that captures the most basic features of real neurons a neuron receives inputs from other neurons via synapses and the output from a neuron is a nonlinear function of a weighted summation of its inputs. There are many different sets of equations that capture these basic features the following set of equations is commonly used ... 

In the second step we need to identify a technical contradiction involving the basic features that have been distinguished. In our simple example, this is easy We have a technical contradiction between strength and weight. ... 

The basic features of a cell membrane are given in Figure 1 to show how it consists essentially of protein molecules incorporated into a semifluid liquid bilayer structure. As a rough guide the plasma membrane of most cells is composed, on a dry weight basis, of nearly equal components of protein and lipid. Because of its nonpolar nature the lipid membrane structure is intrinsically impermeable to polar and electrically charged molecules. For example, turbidity measurements on sarcoplasmic reticulum membranes provide membrane resistance values of 2.6 x 10 and 2.5 X 10 Q cm for the permeability of calcium ions and protons, respectively, while for sodium and potassium ions the corresponding values are... 

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