Research Problems

IL iiicliiilcs general references to aid you in more ileiailed study. Although these references arenot comprehensive, some are key references. Other references provide examples of research problem s n sing these computational methods. 

Advanced users can also benefit from reading this guide. Many people use a lim ited n n mber of algorith m s an d methods for chem -ical calculation s. This book compares of the differen t meth ods in IlyperChem and helps you determine the most appropriate method for your research problems. The book discusses strengths and weaknesses of the methods and algorithms. 

Presell is the basic theory of tjuaiiHim mechanics, particularly, semi-empirical molecular orbital theory. The authors detail and justify the approximations inherent in the semi-empirical Ham illoTi ian s. Includes useful discussion s of th e appiicaliori s of these methods to specific research problems. 

Introduction. When only very small quantities of organic materials are available their manipulation must necessarily be carried out on a correspondingly small scale. This occurs frequently in research problems, but small-scale preparative work is often of value to the student because considerable economy of materials and of time can be achieved. It is emphasised, however, that the proper training for the organic chemist must rest upon the correct understanding and thorough practice of the manipulations on the macro-scale already described, and that he should consider small-scale work as a sequel to and not as a replacement of the above standard techniques. 

The group that has the most difficulty finding appropriate literature are working chemists, not theorists. These are experienced researchers who know chemistry and now have computational tools available. These are people who want to use computational chemistry to address real-world research problems and are bound to run into significant difficulties. This book is for those chemists. 

Although you can investigate many research problems after reading the//yperC/zem Reference Manual HyperChem Computational Chemistry, you may also need information from textbooks and current journals. The following list of selected texts can supply the background necessary for understanding the calculations in HyperChem. 

You will come across numerous examples of qualitative and quantitative methods in this text, most of which are routine examples of chemical analysis. It is important to remember, however, that nonroutine problems prompted analytical chemists to develop these methods. Whenever possible, we will try to place these methods in their appropriate historical context. In addition, examples of current research problems in analytical chemistry are scattered throughout the text. 

Because of the expanded scale and need to describe additional physical and chemical processes, the development of acid deposition and regional oxidant models has lagged behind that of urban-scale photochemical models. An additional step up in scale and complexity, the development of analytical models of pollutant dynamics in the stratosphere is also behind that of ground-level oxidant models, in part because of the central role of heterogeneous chemistry in the stratospheric ozone depletion problem. In general, atmospheric Hquid-phase chemistry and especially heterogeneous chemistry are less well understood than gas-phase reactions such as those that dorninate the formation of ozone in urban areas. Development of three-dimensional models that treat both the dynamics and chemistry of the stratosphere in detail is an ongoing research problem. 

An operations research problem may be remedial in that it seeks to... 

An illustration of an operations research problem for which no model is yet available is the following, which occurs in queueing theory.4 Everyone has observed, and perhaps been displeased to notice, persons in a waiting line, before a theater box-office, for example, who arrive after the observer s arrival, but who go to persons in front to solicit their cooperation in obtaining service. Thus, an... 

Whatever model is used to describe an operations research problem, be it a differential equation, a mathematical program, or a stochastic process, there is a natural tendency to seek a maximum or a minimum with a certain purpose in mind. Thus, one often finds optimization problems imbedded in the models of operations research. 

A Search Problem.—An example of an operations research problem that gives rise to an isoperimetric model is a search problem, first given by B. Koopman,40 that we only formulate here. Suppose that an object is distributed in a region of space with ... 

A third balanced portfolio, of funding mechanisms, is needed if the above-mentioned research frontiers are to be pursued in the most effective manner. Different frontiers will require different mixes of mechanisms, and the decision to use a particular mechanism should be determined by the nature of the research problem, by instramentation and facilities requirements, and by the perceived need for trained personnel in particular areas for industry. This topic is discussed in more detail in Chapter 10. 

In the electronics industry, a large number of relatively small firms play a key role in generating new process concepts and equipment. These firms face important research problems in fundamental science and engineering that would benefit markedly from the insights of academic chemical engineering researchers. Academic researchers should seek out and forge links to these small firms that stand at the crucial step between laboratory research and production processes. Potential mechanisms for accomplishing this are described in Chapter 10. 

Because of these advantages, and because many of the most exciting research problems in chemical engineering lend themselves to the scale and enviromnent of the small research group, grants to individual academic investigators should continue to remain the mainstay of the portfoho of support mechanisms for research. 

The prominent position of quantum mechanics led a coterie of academic theoreticians to think that their approach could solve research problems facing the pharmaceutical industry. These theoreticians, who met annually in Europe and on Sanibel Island in Florida, invented the new subfields of quantum biology [45] and quantum pharmacology [46]. These names may seem curious to the uninitiated. They were not meant to imply that some observable aspect of biology or pharmacology stems from the wave-particle... 

Computational chemists in the pharmaceutical industry also expanded from their academic upbringing by acquiring an interest in force field methods, QSAR, and statistics. Computational chemists with responsibility to work on pharmaceuticals came to appreciate the fact that it was too limiting to confine one s work to just one approach to a problem. To solve research problems in industry, one had to use the best available technique, and this did not mean going to a larger basis set or a higher level of quantum mechanical theory. It meant using molecular mechanics or QSAR or whatever. 

The materials research community is unaware of particular insights or research now being done in chemistry departments and should be exposed to them. (This erroneous view ignores the facts that every industry utilizes all disciplines in attacking research problems, and chemists are already fully involved in industry.)... 

NIDA Research Monographs are prepared by the research divisions of the National Institute on Drug Abuse and published by its Office of Science The primary objective of the series is to provide critical reviews of research problem areas and techniques, the content of state-of-the-art conferences, and integrative research reviews, its dual publication emphasis is rapid and targeted dissemination to the scientific and professional community. 

In this brief closing chapter we take a step backward from the knobs and the tubes and the equations to develop a few general thoughts on the nitty-gritty of how to approach a research problem in biomolecular EPR spectroscopy. 

In order to focus on more of the basic research problems related to radon, a symposium was organized in conjunction with the 191th National Meeting of the American Chemical Society. This volume presents most of the reports given at that symposium. There are five major groups of reports occurrence, measurement methods, physical and chemical properties of radon and its decay products, health effects, and mitigation of radon levels. 

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