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A new thiospinel CuCrZrS 4 has been successfully synthesized by a solid-state chemical reaction. This CuCrZrS 4 exhibits ferromagnetic properties below the Curie temperature at T c = 60 ± 2 K. The appearance of irreversibility between field-cooled (F.C.) and zero-field cooled (Z.F.C.) magnetization is prominent below around 5 K in less than 150 Oe. The ac susceptibility χ AC shows a rapid decrease below ≈10 K. This low-magnetic field behaviour indicates the existence of a reentrant spin glass phase below ≈10 K. The d.c. magnetic susceptibility above 100 K shows Curie-Weiss behaviour with the effective magnetic moment of 3.61 µ B , which is a little less than the spin only value of 3.87 µ B for Cr 3+ ion. The asymptotic Curie temperature θ p is approximately 65 K which is a little higher than T c. The valence state is confirmed to be Cu + Cr 3+ Zr 4+ S 2-4 on the basis of magnetic properties. Electrical resistivity ρ shows a semiconducting temperature dependence over the temperature range 4.2 to 280 K with an activation energy of 6.84×10-3 eV in the higher temperature range 50 to 283 K.

An efficient, accurate HPLC-MS/TQMS method was introduced for the quantitative/qualitative simultaneous analysis of main ingredients, namely geniposide and genipingentiobioside, in the Gardenia fruit. The separation was successfully obtained using a C 8 (100mm×2.1mm, 5μm, 30°C) column by gradient elution with ultrapure water as mobile phase, where flow rate was set to 0.2 ml/min and detection wavelength at 240 nm. The analytical method was validated and the quantification of active compounds, namely genipingentiobioside and gardenoside, was performed. Linearity, precision, repeatability, stability and recovery were also reported. The quantitative analysis revealed that both main ingredients as geniposide and genipingentiobioside have performed a good linear relationship in 0.1-100 mg/ml concentration range (r=1.00000 and r =0.99998). The average content was measured to be 4.842% with RSD 0.96% for geniposide and 1.1976% with RSD 0.47% for genipingentiobioside in the Gardenia fruit. Accordingly, this method would be feasible for the quantity and quality control of crude drugs.

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