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Materials science is an interdisciplinary field involving the properties of matter and its applications to various areas of science and engineering. This science investigates the relationship between the structure of materials and their properties. It includes elements of applied physics and chemistry, as well as chemical, mechanical, civil and electrical engineering. With significant media attention to nanoscience and nanotechnology in the recent years, materials science has been propelled to the forefront at many universities, sometimes controversially.

Nuclear chemistry is a subfield of chemistry dealing with radioactivity, nuclear processes and nuclear properties. * It is the chemistry of radioactive elements such as the actinides, radium and radon together with the chemistry associated with equipment (such as nuclear reactors) which are designed to perform nuclear processes. This includes the corrosion of surfaces and the behavior under conditions of both normal and abnormal operation (such as during an accident). An important area is the behavior of objects and materials after being placed into a waste store or otherwise disposed of. The study of the chemical effects resulting from the absorption of radiation within living animals, plants, and other materials. The radiation chemistry controls much of radiation biology as radiation has an effect on living things at the molecular scale, to explain it another way the radiation alters the biochemicals within an organism, the alteration of the biomolecules then changes the chemistry which occurs within the organism, this change in biochemistry then can lead to a biological outcome. As a result nuclear chemistry greatly assists the understanding of medical treatments (such as cancer radiotherapy) and has enabled these treatments to improve. the study of the production and use of radioactive sources for a range of processes. These include radiotherapy in medical applications; the use of radioactive tracers within industry, science and the environment; and the use of radiation to modify materials such as polymers . the study and use of nuclear processes in non-radioactive areas of human activity. For instance, nuclear magnetic resonance (NMR) spectroscopy is commonly used in synthetic organic chemistry and physical chemistry and for structural analysis in macromolecular chemistry.

Nuclear magnetic resonance (NMR)

NMR spectroscopy uses the net spin of nuclei in a substances upon energy absorption to identify molecules. This has now become a standard spectroscopic tool within synthetic chemistry. One major use of NMR is to determine the bond connectivity within an organic molecule. NMR imaging also uses the net spin of nuclei (commonly protons) for imaging. This is widely used for diagnostic purposes in medicine, and can provide detailed images of the inside of a person without inflicting any radiation upon them. In a medical setting, NMR is often known simply as "magnetic resonance" imaging, as the word 'nuclear' has negative connotations for many people.

Electrochemistry is a branch of chemistry that studies the reactions which take place at the interface of an electronic conductor (the electrode composed of a metal or a semiconductor, including graphite) and an ionic conductor (the electrolyte). If a chemical reaction is caused by an external voltage, or if a voltage is caused by a chemical reaction, as in a battery, it is an electrochemical reaction. In general, electrochemistry deals with situations where an oxidation and a reduction reaction are separated in space. The direct charge transfer from one molecule to another is not the topic of electrochemistry.

Immunochemistry is a branch of chemistry that involves the study of the reactions and components on the immune system. Various methods in immunochemistry has been developed and refined, and been used in scientific study, from virology to molecular evolution. One of the earliest examples of immunochemistry is the Wasserman test to detect Syphilis. Svante Arrhenius was also one of the pioneers in the field; he published Immunochemistry in 1907 which described the application of the methods of physical chemistry to the study of the theory of toxins and antitoxins.

Sonochemistry is concerned with understanding the effect of sonic waves and wave properties on chemical systems. Since acoustic waves have unique physical properties, the corresponding atomic and molecular chemistry is unique as well. Often these effects are most apparent in ultrasonic systems. This is demonstrated in phenomena such as ultrasound, sonication, sonoluminescence and sonic cavitation. For example, in chemical kinetics, it has been observed that ultrasound can greatly enhance chemical reactivity in a number of systems; effectively acting as a catalyst by exciting the atomic and molecular modes of the system (such as the vibrational, rotational, and translational modes). In addition, in reactions that use solids, ultrasound breaks up the solid pieces from the energy released from the bubbles created by cavitation collapsing through them. This gives the solid reactant a larger surface area for the reaction to proceed over, increasing the observed rate of reaction. Ultrasound produces radicals in liquids due to the high temperatures and pressures experienced locally when a bubble collapses. While the application of ultrasound often generates mixtures of products, a paper published in 2007 in the journal Nature described the use of ultrasound to selectively effect a certain cyclobutane ring-opening reaction.Sonochemistry can be performed by using a bath (usually used for ultrasonic cleaning) or with a high power probe.

Phytochemistry is in the strict sense of the word the study of phytochemicals. These are chemicals derived from plants. In a narrower sense the terms are often used to describe the large number of secondary metabolic compounds found in plants. Many of these are known to provide protection against insect attacks and plant diseases. They also exhibit a number of protective functions for human consumers. Techniques commonly using in the field of phytochemistry are extraction, isolation and structural elucidation (MS,1Dand 2D NMR) of natural products, as well as various chromatography techniques (MPLC, HPLC, LC-MS). Phytochemistry is widely used in the field of Chinese medicine especially in the field of herbal medicine.

In most cases, biologically active compounds in Chinese medicine or herbal medicine have not been determined. Therefore, it is important to use the phytochemical methods to screen and analyze bioactive components, not only for the quality control of crude drugs, but also for the elucidation of their therapeutic mechanisms. Modern pharmacological studies indicate that binding to receptors or ion channels on cell membrane is the first step of some drug actions. A new method in phytochemistry; biochromatography, has been developed. This method combines human red cell membrane extraction and high performance liquid chromatography to screen potential active components in Chinese medicine.

Thermochemistry is the study of the heat evolved or absorbed in chemical reactions. Thermochemistry, generally, is concerned with the heat exchange accompanying transformations, such as mixing, phase transitions, chemical reactions, etc., which includes calculations of such quantities as the heat capacity, heat of combustion, heat of formation, etc. The laws of thermochemistry rest on two statements: