The soybean cyst nematode (SCN), Heterodera glycines Ichinohe, is a severe pest of soybean, Glycine max (L.) Merr., in the United States. Nematode reproduction and the seed yield losses caused by this nematode are influenced by soil texture (3,5,6). Todd and Pearson (5) recovered higher numbers of SCN females and cysts from a sandy loam soil than from silty loams. Soybean yield also has been ne...

Particles with nanometer dimensions (nanoparticles) are all around us. The finest particles of sand are blown by the wind over thousands of kilometers. The finest particles of soils are either eroded by the wind in extremely dry conditions or by water under wet conditions and deposited hundreds of kilometers or more from the origin. The air contains nanoparticles of carbon, ice, and oxides and ...

X-ray analyses of the clay minerals from thousands of sediments indicate that any of the major clay minerals can occur in abundance in any of the major depositional environments and there is no consistent coincidence between specific clay minerals and specific depositional environments. It is concluded that the great majority of clay minerals in sedimentary rocks are detrital in origin, strongl...

Adsorption of organic cations on several clay minerals is reviewed with an emphasis on the effect of ionic strength and modeling. The clay exchanged with suitable organic cations forms a basis for ecologically acceptable formulations of herbicides with reduced leaching, ground water contamination and enhanced weed control efficacy. Incomplete neutralization of the clay surface charge by an orga...

" A supplement of 1% to 4% clay or 4% salt mixture caused an increase in body weight and prevented the pathologic changes. " " Findings indicated that the various clays differed significantly in growth-promoting activity (Table 4). The most active material tested was clay sample A (ION-MIN from CEM); whereas, clay sample J, kaolin, and hydrobiotite were virtually devoid of growth-promoting acti...

Focus here is placed on the pharmaceutical and biomedical applications of novel clay-drug hybrid materials categorized by methods of administration. Clay minerals have been used for many years as pharmaceutical and medicinal ingredients for therapeutic purposes. A number of studies have attempted to explore clay-drug hybrid materials for biomedical applications with desired functions, such as s...

Second harmonic generation (SHG) is applied for the first time to study the surfaces of clay particles. An SHG signal was detected from an aqueous suspension of disk-shaped montmorillonite clay particles of 0.5 μm diameter and 0.01 μm thickness. The origin of the SHG signal is the polarization of water molecules by surface charges located in the edge region of the clay particles. On addition of...

Pillared clays (PILCs) are interesting materials mostly due to their high basal spacing and surface area, which make them suitable for adsorption and catalysis applications, for example. However, the production of these materials on industrial scale is dependent on research about what parameters influence the process. Thus, the objective of this work was to evaluate what parameters influence th...

Clay mineral studies in the U.S.S.R., mainly since 1960, are summarized. Electron diffraction techniques especially have been developed and used extensively. Methods have been developed for simultaneous recording of DTA curves and other properties. Polytypism of phyllosilicates has been studied intensively by Zvyagin and others. Mucfi new information on the structure and morphology of halloysit...

Isolated patches of white clay occurring in the terminal moraine of Long Island, Staten fsland, and southern New Jersey have been mentioned in a number of geologic descriptions. Such an occurrence was recently encountered during excavation for a building site and samples were submitted to the mineralogical laboratory of Columbia University for identification by Messrs. Schoonmaker and Kirkman. ...