In the present work, the performances of improved two-stage multi inter-cooler trans- critical carbon dioxide (CO2) refrigeration cycles with ejector and internal heat exchanger have been examined. In the new improved cycles, an internal heat exchanger is append to the cycles. Also, second inter-cooler in improved cycles, cooled with the refrigeration of the cycle, so that in first c...

BACKGROUND Stand-up paddle-boarding is an increasingly popular water sport; however no published data to our knowledge exists on the nature and type of injuries sustained in this sport. OBJECTIVES This study aims to describe the frequency, pattern, and mechanism of paddle-boarding injuries. MATERIALS AND METHODS Descriptive data of paddle-boarding injuries were collected using an interactiv...

The novel copper(II) coordination compound, [Cu2(O2CH)4(nia)2] (nia = nicotinamide), was isolated from the reaction mixture containing Cu2(OH)2CO3, nicotinamide, methanoic acid and ethanol. The new complex was characterized by X-ray single crystal diffraction and other standard physico-chemical methods. The structure contains binuclear centrosymmetric molecules in which two central atoms are br...

The title complex, [Cu(2)(CH(3)COO)(4)(C(16)H(12)N(2)O(2))(2)], forms a dimer of the paddle-wheel type located on a crystallographic inversion centre. The two Cu(II) atoms [Cu⋯Cu = 2.7254 (11) Å] are bridged by four acetate anions. The geometry of the polyhedron around the metal centre can be described as tetra-gonal-pyramidal derived from the calculation of the value τ = 0.0018. The apical pos...

The adsorption capacity and selectivity of carbon dioxide and nitrogen at 298 K have been evaluated for two series of MMOFs built on metal paddle-wheel building units, including non-interpenetrated Zn(BDC)(TED)(0.5) (1), Zn(BDC-OH)(TED)(0.5) (2), Zn(BDC-NH(2))(TED)(0.5) (3), and interpenetrated Zn(BDC)(BPY)(0.5) (4), Zn(BDC)(DMBPY)(0.5) (5), Zn(NDC)(BPY)(0.5) (6) and Zn(NDC)(DMBPY)(0.5) (7) fra...