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The synthesis and structure of a new flexible metal-organic framework Ni(2)(2,6-ndc)(2)(dabco) (DUT-8(Ni), DUT = Dresden University of Technology, 2,6-ndc = 2,6-naphthalenedicarboxylate, dabco = 1,4-diazabicyclo[2.2.2]octane) as well as its characterization by gas adsorption and (129)Xe NMR spectroscopy is described. The compound shows reversible structural transformation without loss of crystallinity upon solvent removal and physisorption of several gases. Xenon adsorption studies combined with (129)Xe NMR spectroscopy turn out to be favorable methods for the detection and characterization of the so-called "gate-pressure" effect in this novel MOF material. The linewidth and chemical shift of the (129)Xe NMR signal are shown to be very sensitive parameters for the detection of this structural transition from a narrow pore system with low porosity to a wide pore state. The transition and threshold temperature is clearly detected.

Microporous hydrophobic polysilanes with high specific surface areas (700-1100 m2 g(-1)) for applications in gas adsorption are obtained using an organolithiation route.

tic acid 27 ml L -1 , surface agent 20-30 mg L -1 , IF-MoS 2 and 2H-MoS 2 3 g L -1 , pH=4.8-5.1, temperature at 353-358 K and the depositing time is 2 h. The electroless coatings were treated at 673 K for 2 h in vacuum. The surface morphology of the coatings was characterized by scanning electron microscopy (SEM, FSEM SIRION JY/ T010-1996).The tribological properties of the coatings were investigated using a pin-ondisk wear tester (MMW-1) under unlubricated condition in air (relative humidity 60 %) at sliding speed of 0.126 m s -1 . The spherical pins with radius of 5 mm were fabricated by quenched-and-tempered medium carbon steel with a hardness of HB220. The test loads ranged from 50 to 120 M. Friction coefficient were calculated by dividing the friction force that was recorded on line via torque as measured by the strain gauge. Mass loss was measured with an analytical balance at an interval of 5 min throughout the test. The worn surfaces of the electroless coatings were observed also by scanning electron microscopy (SEM, FSEM SIRION JY/T010-1996).

129Xe NMR measurements of adsorbed xenon are shown for the first time to be a suitable tool to characterize the porosity and the properties of the metal-organic framework Cu3(BTC)2(H2O)3 (BTC = benzene 1,3,5-tricarboxylate). The NMR experiments are performed at room temperature and over a wide range of xenon pressure and on two different synthesized Cu3(BTC)2 samples. 129Xe NMR results reveal that in dependence on the kind of the synthesis pathway either one or two signals are observed which can be attributed to two kinds of fast exchange of xenon atoms in two pores with different pore sizes. Coadsorption experiments of xenon and ethylene demonstrate that the xenon atoms prefer to fill the greater pores of the material because the smaller pores are occupied with residual molecules from the synthesis procedure and additionally adsorbed ethylene. Besides the NMR experiments a series of electron paramagnetic resonance (EPR) measurements are performed to estimate the state of copper having a strong influence on the chemical shift of the adsorbed xenon. The EPR experiments demonstrate that spin exchange between the interconnected copper dimers is taking place across the BTC linker molecules in the Cu3(BTC)2 framework.