Benchmarking fundamentals

The counterflow configuration has been extensively utilized to provide benchmark experimental data for the study of stretched flame phenomena and the modeling of turbulent flames through the concept of laminar flamelets. Global flame properties of a fuel/oxidizer mixture obtained using this configuration, such as laminar flame speed and extinction stretch rate, have also been widely used as target responses for the development, validation, and optimization of a detailed reaction mechanism. In particular, extinction stretch rate represents a kinetics-affected phenomenon and characterizes the interaction between a characteristic flame time and a characteristic flow time. Furthermore, the study of extinction phenomena is of fundamental and practical importance in the field of combustion, and is closely related to the areas of safety, fire suppression, and control of combustion processes. 

After the discovery of the combined charge and space symmetry violation, or CP violation, in the decay of neutral mesons [2], the search for the EDMs of elementary particles has become one of the fundamental problems in physics. A permanent EDM is induced by the super-weak interactions that violate both space inversion symmetry and time reversal invariance [11], Considerable experimental efforts have been invested in probing for atomic EDMs (da) induced by EDMs of the proton, neutron, and electron, and by the P,T-odd interactions between them. The best available limit for the electron EDM, de, was obtained from atomic T1 experiments [12], which established an upper limit of de < 1.6 x 10 27e-cm. The benchmark upper limit on a nuclear EDM is obtained from the atomic EDM experiment on Iyt,Hg [13] as d ig < 2.1 x 10 2 e-cm, from which the best restriction on the proton EDM, dp < 5.4 x 10 24e-cm, was also obtained by Dmitriev and Senkov [14]. The previous upper limit on the proton EDM was estimated from the molecular T1F experiments by Hinds and co-workers [15]. 

High-performance liquid chromatography (HPLC) is one of the most widespread analytical and preparative scale separation techniques used for both scientific investigations and industrial and biomedical analysis. Now in its second edition, this revised and updated version of the Handbook of HPLC examines the new advances made in this field since the publication of the benchmark first edition twelve years ago. It reports detailed information on fundamental and practical aspects of HPLC related to conventional format and sophisticated novel approaches that have been developed to address a variety of separation problems in different fields. 

Product yields in the radiolysis of water are required for a number of practical and fundamental reasons. Model calculations require consistent sets of data to use as benchmarks in their accuracy. These models essentially trace the chemistry from the passage of the incident heavy ion to a specified point in time. Engineering and other applications often need product yields to predict radiation damage at long times. Consistent sets of both the oxidizing and reducing species produced in water are especially important to have in order to maintain material balance. Finally, it is impossible to measure the yields of all water... 

As already mentioned, in the case of semiconductor surfaces there is often a strong surface rearrangement upon adsorption due to the covalent bonding of the semiconductor substrate. The benchmark system for the study of the adsorption and desorption dynamics at semiconductor surfaces is the interaction of hydrogen with silicon surfaces [2, 61]. Apart from the fundamental interest, this system is also of strong technological relevance for the growth and passivation of semiconductor devices. 

The other approach to the electronic wave function and its links with the molecular parameters is the ab initio calculation we often use this term or mode of description elsewhere in this book. An ab initio calculation is one which uses only the fundamental laws of physics and the values of the fundamental constants. It is easy to define, but efforts to achieve success for molecules with many electrons, even diatomic molecules, have occupied the attention of many for the past seventy years. The electronic wave function produced by an ab initio calculation is often too complicated algebraically to provide something which can reasonably be described as a physical picture. In this situation the value of a molecular parameter, determined by experiment, is best regarded as a benchmark which can be used to test the accuracy of an ah initio calculation. 

The model system comprising the reaction sequence from initial 0-atom attack to steady-state erosion of a hydrocarbon surface can serve as a benchmark for fundamental atom-surface interactions at hyperthermal collision energies and for etching mechanisms of materials. Within this model system, there is still much to learn. It is likely that when a hyperthermal oxygen atom strikes a saturated hydrocarbon surface, it will either abstract a hydrogen atom or it will scatter inelastically. The subsequent reaction sequence becomes murky. Very little is known about the mechanisms of oxidation, surface roughening, or material loss. In fact, even the sticking... 

Allen BC, Kavlock RJ, Kimmel CA, and Faustman EM (1994) Dose-response assessments for developmental toxicity II. Comparison of generic benchmark dose estimates with NOAELs. Fundamental and Applied Toxicology 23 487-A95. 

A fundamental concept essential to the currently defined approaches for determining GMO safety is that of substantial equivalence (SE). Used as the basis for establishing a comparative benchmark, SE depends on two key concepts. Eirst, existing traditional foods are assumed to be safe as evidenced by their longterm use. Second, the response to traditional foods can be used as a basis for comparison to transgenically modified foods which are often derived from traditional foods. 

Fundamentally, this audit tool is designed to improve accountability and business planning processes, which, in turn, boost corporate adaptability and market responsiveness to enhance the economic, social, and environmental triple bottom line of participating corporate partners. As the field of CSR/SRI continues to develop and mature, we anticipate that tools like the CAP Gap Audit will be refined to assist industry leaders in benchmarking best-in-class standards for particular industries. 

A major advance in the efficiency of FCI calculations was the introduction of a factorized direct Cl algorithm by Siegbahn. This involves formulating the FCI calculation as a series of matrix multiplications an ideal algorithm for exploiting the power of current vector supercomputers. This algorithm is fundamental to our present ability to perform FCI benchmarks, and we discuss it in detail. We consider only the two-electron contribution to a given by Eq. (11), which can be written as... 

Reduction of combustion-generated noise from high-speed jet flows is the topic discussed in Section 2. Fundamental research and novel noise-reduction techniques are presented. These include detailed experimental and computational studies of jet-plume noise, as well as precise measurements. A narrow-band acoustic database generated from actual aircraft landing practice is used as a benchmark for the development of the effective noise-suppression technology. 

The electronic spectra of the five-membered ring compounds have been intensively studied by the experimental and theoretical works. These molecules are fundamental units in many important biological systems. Furthermore, their excitation spectra are benchmark examples for theoretical studies of molecular excited states [51,55-58]. For furan and thiophene, various types of excitation spectra were measured the vacuum ultraviolet (VUV) spectrum, electron energy-loss (EEL) spectrum and magnetic circular dichroism (MCD) spectrum. The SAC-Cl method offered consistent interpretations of these electronic spectra [51-53]. 

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