The thermal degradation characteristics of selected organoplatinum antitumor agents

The thermal decomposition characteristics of representatives of three classes of organoplatinum compounds have been examined by thermogravimetry. Substituted salicylato(1,2-diaminocyclohexane)platinum(II) compounds undergo thermal decomposition by sequential loss of first the salicylato ligand and then the amine ligand to afford a residue corresponding to the platinum content of the compound. The thermal decomposition of N-arylsalicylaldimino(1,2-diaminocyclohexane)platinum(II) nitrate is more complex, but is also characterized by two major weight losses. Thermal decomposition ofbis-(2-thiophenecarboxylato)platinum(II) is characterized by ligand fragmentation to generate a residual mass corresponding to the platinum content of the compound.     

Internal irradiation effects in239Pu doped K2Ca2(SO4)3): EPR,TSL and PAS investigations

The electron/hole trapped centres created during internal irradiation in²³⁹Pu doped K₂Ca₂(SO₄)₃ were investigated using electron paramagnetic resonance (EPR), thermally stimulated luminescence (TSL) and photoacoustic spectroscopic studies (PAS). These techniques were used to identify the defects and characterize the thermally induced relaxation processes. TSL studies of self (α)/γ-irradiated²³⁹Pu doped K₂Ca₂(SO₄)₃ revealed two glow peaks around 400 and 433K. Plutonium introduced as Pu⁴⁺ was partly reduced to Pu³⁺ due to self irradiation. This was ascertained from PAS studies. EPR studies carried out on these samples showed the formation of radical ions SO ₄ ⁻ , SO ₃ ⁻ , O ₃ ⁻ , etc. The thermal destruction of SO ₄ ⁻ ion was found to be associated with the prominent glow peak around 433K. Pu³⁺ was found to act as luminescent centre for the observed TSL glow. The trap depth for the glow peak at 433K has been determined from TSL and EPR data.     

Stereochemistry and structural phase transition of Cu(II) complexes containing orthophosphate ions and pyridine/picoline

Copper complexes of the type Cu(L)₄(H₂PO₄)₂ designated as complex (I), and Cu(L)₄ HPO₄ designated as complex (II), (whereL = pyridine (py) or λ-picoline (pic)) have been synthesised, characterised by chemical analyses, IR, and electronic and magnetic susceptibility data. From ESR studies it is concluded that complexes (I) have elongatedtrans octahedral stereochemistry. The temperature dependence of the ESR spectrum of Cu(py)₄(H₂PO₄)₂ suggests a fluxional behaviour in the immediate coordination of Cu(II), whereas very little variation of the ESR spectrum of the Cu(pic)₄(H₂PO₄)₂ complex indicates that the stereochemistry of this complex is essentially static in nature. The differential scanning calorimetric studies in the case of Cu(py)₄(H₂PO₄)₂ complex have given clear evidence for the occurrence of a structural phase transition at 147 K. The absence of any abrupt changes in the ESR spectrum at that temperature excludes the possibility of any changes in the immediate environment of Cu(II).     

Hollow gold and platinum nanoparticles by a transmetallation reaction in an organic solution

Transmetallation reaction between hydrophobized silver nanoparticles with hydrophobized chloroaurate and chloroplatinate ions in chloroform results in the formation of hollow gold and platinum shell nanoparticles respectively.     

Exact two-qubit universal quantum circuit

We provide an analytic way to implement any arbitrary two-qubit unitary operation, given an entangling two-qubit gate together with local gates. This is shown to provide explicit construction of a universal quantum circuit that exactly simulates arbitrary two-qubit operations in SU(4). Each block in this circuit is given in a closed form solution. We also provide a uniform upper bound of the applications of the given entangling gates, and find that exactly half of all the controlled-unitary gates satisfy the same upper bound as the CNOT gate. These results allow for the efficient implementation of operations in SU(4) required for both quantum computation and quantum simulation.     

A lipophilic hexaporphyrin assembly supported on a stannoxane core

Lipophilic hexaporphyrin free-base and copper-metalated assemblies supported on a Sn6O6 core have been synthesized and characterized. The nuclease activity of the copper derivative has been studied.