Phosphasilenes, P=Si doubly bonded compounds, have received considerable attention due to their unique physical and chemical properties. We report on the synthesis and structure of a chlorophosphasilene coordinated by an N-heterocyclic carbene (NHC), which has the potential of functionalization at the Si-Cl moiety. Treatment of a silylphosphine, ArPH-SiCl₂RSi (Ar = bulky aryl group, RSi = Si(Si...

Symmetry has been dealt with in a wide variety of elds in both art and science. Symmetry and asymmetry as aesthetic features have been used in architecture, sculptures and paintings. Symmetry and symmetric groups have been de ned in mathematics [31]. Symmetry and it's compliment feature Chirality are basic properties of molecular structure that mediate chemical properties [29]. Though symmetry ...

Since the late 1970's, dozens of researchers, scholars, skeptics and "professional debunkers" have presented their theories on how the image on the Shroud of Turin was formed. Some are based on serious science while others show a complete lack of understanding of the Shroud image or its properties. In this paper, I will review the "proto-photography" theory proposed by Prof. Nicholas Allen of S...

Freshly prepared 2% acid and alkaline glutaraldehyde solutions were stored at 4, 20, and 37 C. At intervals, samples were removed and changes in pH, ultraviolet spectrum, and sporicidal activity (against Bacillus pumilus spores) were recorded. Alkaline solutions stored at 4 C showed little changes in these properties, whereas such solutions stored at 37 C became turbid and showed a decrease in ...

1. Introduction. In [5] Mazur constructed a homotopy 4-sphere which looked like one of the strongest candidates for a counterexample to the 4-dimensional Poincaré Conjecture. In this paper we show that Mazur's example is in fact a true 4-sphere after all. This raises the odds in favour of the 4-dimensional Poincaré Conjecture. The proof involves a smooth knot of S2 in S4 with unusual properties.

Crystal engineering is discussed, along with its three key concepts: crystal packing; the design of solids; and physical and chemical properties.

Carbon is a major player in the evolutionary scheme of the universe because of its abundance and its ability to form complex species. It is also a key element in the evolution of prebiotic molecules. The different forms of cosmic carbon are reviewed ranging from carbon atoms and carbon-bearing molecules to complex, solid-state, carbonaceous structures. The current state of knowledge is assessed...

a National Engineering Laboratory of Soil Nutrient Management, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, China b Soil Erosion and Degradation Research Group, Department of Geography, University of Valencia, Valencia, Spain c Soil Physics and Land Management Group, Wageningen University, Droevendaalsesteeg 4, 6708PB Wageningen, The Netherlands d University of Ch...

We generalize graded Hecke algebras to include a twisting twococycle for the associated finite group. We give examples where the parameter spaces of the resulting twisted graded Hecke algebras are larger than that of the graded Hecke algebras. We prove that twisted graded Hecke algebras are particular types of deformations of a crossed product.