Boron-Carbon-Nitrogen Compounds

The B-C-N compounds are attractive materials due to their unique properties associated with their layered, graphite-like structures [246, 247]. Such compositions can be deposited by the CVD of a mixture of BCI3, ammonia and a hydrocarbon (usually acetylene) at temperatures between 700-1700 °C [247-249]. A compound with the composition BC2N has been obtained by the CVD of a mixture of BCI3 and acetonitrile 

---

Laser isotope separation techniques have been demonstrated for many elements, including hydrogen, boron, carbon, nitrogen, oxygen, sHicon, sulfur, chlorine, titanium, selenium, bromine, molybdenum, barium, osmium, mercury, and some of the rare-earth elements. The most significant separation involves uranium, separating uranium-235 [15117-96-1], from uranium-238 [7440-61-1], (see Uranium and uranium compounds). The... 

Application of the equivalent cores method to solid compounds is slightly more complicated, requires additional assumptions, and is therefore less accurate than the application to gaseous compounds. However, fairly good correlations have been obtained for solid compounds of boron, carbon, nitrogen, and iodine20. The correlations were restricted, because of the nature of the assumptions involved, to molecular compounds or to compounds in which the core-ionized atoms are in anions. 

Other elements with which iron forms binary compounds, especially at higher temperatures, are boron, carbon, nitrogen, silicon, and phosphorus, l.ike FeO, these compounds often depart slightly or even considerably from daltonide composition, frequently being interstitial compounds, and in higher elements of groups VB and VIB, merging into the interstitial compound-solid solution picture which iron exhibits with the transition metals. 

During the introduction of this review, reference was made to the classical rule of the double bond. The theory, which in its original predictions supports the exceptional position for the elements boron, carbon, nitrogen, and oxygen, has lost its validity and needs modifications, as can be seen from the erratic increase in the numbers of compounds that contradict the rule that have been discovered within the last 12 years. These compounds are not found only as low-valent phosphorus-carbon species, but also increasingly as heteronuclear and even homonuclear molecules built up by heavier elements of the fourth to sixth main groups, such as Si, Ge, As, Sb, S, and Se. 

ZIRCAT (7440-67-7) Finely divided material is spontaneously flammable in air may ignite and continue to bum under water. Violent reactions with oxidizers, alkali hydroxides, alkali metals (and their compounds), carbon tetrachloride, cupric oxide, lead, lead oxide, lead peroxide (combined material can burn explosively, and is sensitive to friction and static electricity), nitryl fluoride, oxygen difluoride, phosphoms, potassium, potassium compounds (potassium chlorate, potassium nitrate), sodium borate, sodium hydroxide. Explodes if mixed with hydrated borax when heated. Contact with lithium chromate may cause explosion above 752°F/450°C. Forms explosive mixture with potassium chlorate. Dusts of zirconium ignite and explode in a carbon dioxide atmosphere. Contact with ammonium-V-nitrosophenylhydroxylamine above 104°F/40°C forms an explosive material. Incompatible with boron, carbon, nitrogen, halogens, lead, platinum, potassium nitrate. In case of fire, use approved Class D extinguishers or smothering quantities of dry sand, crushed limestone, clay. 

The result is that the first element of the main groups (lithium, beryllium as well as boron, carbon, nitrogen, oxygen, and fluorine described in Chapter 12) are different from the rest of their group members. Usually, the first element is much smaller than the rest of the elements in that group, and it tends to form covalent compounds and complexes. This tendency is called Fajans rule after Kazimierz Fajans, a physical chemist who in 1923 postulated it. 

Binary compounds can be made with uranium. Such solids state compounds have been investigated because they have interesting magnetic properties. They are made by direct interaction with uranium metal. Oxides mainly form with the general formula UO2, UjOg, UO2. The metal also reacts with other elements such as boron, carbon, nitrogen, phosphorus, and arsenic to make semi-metallic solids. Compounds can also be made using silicon, sulfur, selenium, and tellurium. Urinates can be formed by the addition of uranium with alkali and alkaline Earth metals. 

The Miedema modeP describes bonding in intermetallic, ordered compounds of metallic elements. In addition to the metallic elements the model also includes the elements hydrogen, boron, carbon, nitrogen, silicon, and phosphorus in their metallic... 

The search for effective electrocatalysts led to investigations of the corrosive resistance and of the reactivity for the O2 reduction of compounds of metals with other elements like boron, carbon, nitrogen, oxygen, etc. The cathode [78] of the Bacon cell represents the classical example. The porous cathodes were made by pressing and sintering mixtures of carbonyl nickel and ammonium bicarbonate. Subsequently, they were coated with a layer of lithiated nickel oxide. 

A remarkable variety of compounds in the Ca-(B,C,N) system has opened a window for research in related fields. With the elements boron, carbon and nitrogen, substance classes such as borocarbides, boronitrides, and carbonitrides can be considered to contain anionic derivatives of binary compounds B4C, BN, and C3N4. Until now, most compounds in these substance classes have been considered to contain alkali, alkaline-earth, or lanthanide elements. Lanthanide borocarbides are known from the work of Bauer [1]. Lanthanide boronitrides represent a younger family of compounds, also assigned as nitridoborates [2] following the nomenclature of oxoborates. 

Chemically, tungsten is rather inert, but it will form compounds with several other elements at high temperatures (e.g., the halogens, carbon, boron, silicon, nitrogen, and oxygen). Tungsten will corrode in seawater. 

There are several materials that form nanotubes including boron-nitrogen compounds. Here we will focus on nanotubes derived from carbon. Carbon nanotubes (CNTs) have... 

The evolution of a lake or pond into dry land depends on the presence of nutrients in the water. The term nutrients refers to elements and compounds that are necessary for the growth of plants. Nutrients are commonly divided into two categories major nutrients and minor nutrients, also known as micronutrients. Despite some differences in the way that various elements and compounds are classified, carbon, nitrogen, and phosphorus are always regarded as major nutrients. Some authorities also list potassium, sulfur, calcium, magnesium, and/or iron as major nutrients. Micronutrients include aluminum, boron, chlorine, copper, manganese, molybdenum, silicon, and zinc. 

---