If a chemical symbol has a subscript associated with it, there are multiple atoms of that element in the compound. Unless they are part of a polyatomic ion, each atom of that element is an individual ion. For example, iron (III) sulfate is written Fe2(SO4)3. The +3 oxidation state of...
it is taught (in my math class) that the set of natural numbers starts at 1. But after finding out that some people use a different convention starting with 0, I just stick with "non-negative integers" and "positive integers" because these have much more absolute definitions. Unfortunately ...
2) Sir William Thomson, (Lord Kelvin) "The Size of Atoms" Nature XXVIII, 203-205 (June 28, 1883), 250-254 (July 12, 1883), 274-278 (July 19, 1883) I wish in the beginning to beg you not to run away from the subject by thinking of the exceedingly smallness of atoms. Atoms ar...
The number of parents teaching their offspring at home will increase if the current public school system continues to be viewed as an irrelevant institution that can hinder a child’s ability to learn. The rise of home-schooling reflects broadening dissatisfaction with formal education in the US....
Molecular modeling software depicts three-dimensional images of a chemical. Mathematical operations adjust the positions of the atoms in the molecule in an attempt to accurately portray the size and shape of the drug, and the location of any charged groups. Chemists can vary the atoms or groups ...
Neurogenesis has recently been observed in the adult human brain, suggesting the possibility of endogenous neural repair. However, the augmentation of neur... MA Curtis,EB Penney,AG Pearson,... - 《Proceedings of the National Academy of Sciences of the United States of America》 被引量: 984发...
the of and to a in that is was he for it with as his on be at by i this had not are but from or have an they which one you were all her she there would their we him been has when who will no more if out so up said what its about than into them can only other time new...
Introduction Over fifty years ago, Altman and Das showed new neurons are generated in the adult mammalian hippocampal dentate gyrus (DG) [1–3], thus disproving the long-standing belief that neurogenesis ceases at birth. We now know a great deal about the function and regulation of adult DG ...