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Solvothermal reactions of zinc and cadmium nitrates with 1,3,5-tri-4-pyridyl-1,2-ethenylbenzene (tpeb) in the presence of various carboxylic acids including 4-iodobenzoic acid (4-HIBA), benzene-1,4-dicarboxylic acid (1,4-H2BDC), 2,5-furandicarboxylic acid (2,5-H2FDC), 2,5-dibromoterephthalic acid (2,5-H2DBTPA), 1,2-cyclohexanedicarboxylic acid (1,2-H2CHDC), and 1,5-pentanedioic acid (1,5-H2PDC) gave rise to eight coordination complexes, viz, [Zn(tpeb)2(4-IBA)2]·2H2O (1), {[Cd(NO3)(tpeb)(4-IBA)]·H2O}n (2), {[Cd2(NO3)2(tpeb)2(1,4-BDC)]}n (3), {[Cd2(tpeb)2(2,5-FDC)2]·2H2O}n (4), [Cd(tpeb)(2,5-DBTPA)2]n (5), {[Cd2(H2O)2(tpeb)2(1,2-CHDC)2]·H2O}n (6), [Zn(tpeb)(1,2-CHDC)]n (7), and {[Zn(tpeb)(1,5-PDC)]·H2O}n (8). Compound 1 is a discrete mononuclear complex with its Zn(II) center coordinated by two pairs of tpeb and 4-IBA ligands. Compound 2 has a 2D waterfall-like network constructed from bridging [Cd(NO3)(4-IBA)] units with tpeb ligands. Compounds 3, 4, and 5 contain similar 1D [Cd(tpeb)]n chains, which are l...

Solvothermal reactions of Cd(NO3)2·4H2O with 4-pyr-poly-2-ene (ppene) in the presence of benzene-1,2-dicarboxylic acid (1,2-H2BDC), benzene-1,3-dicarboxylic acid (1,3-H2BDC), benzene-1,4-dicarboxylic acid (1,4-H2BDC), benzene-1,3,5-tricarboxylic acid (1,3,5-H3BTC), or 4,4′-oxidibenzoic acid (4,4′-H2OBA) afforded five Cd(II) coordination polymers [Cd(ppene)(1,2-BDC)]n (1), [Cd(ppene)(1,3-BDC)]n (2), [{Cd(ppene)(1,4-BDC)}·MeCN]n (3) (Liu et al. Inorg. Chem. Commun. 2015, 58, 1−4), [{Cd(ppene)(1,3,5-HBTC)}·0.5(ppene)]n (4), and [Cd(ppene)(4,4′-OBA)]n (5), respectively. Upon UV light irradiation, 1, 3, and 4 can undergo a double [2 + 2] cycloaddition reaction to yield their corresponding photoproducts including [Cd2(4-tp-3-lad)(1,2-BDC)2]n (1a, 4-tp-3-lad = 2,3,5,6-tetra(pyridin-4-yl)bicyclo[2.2.0]hexane), [{Cd2(4-tp-3-lad)(1,4-BDC)2}·2MeCN]n (3a), and [{Cd2(4-tp-3-lad)(1,3,5-HBTC)2}·(ppene)]n (4a) in a single-crystal-to-single-crystal manner. Compounds 1, 2, 4, 5, 1a, 3a, and 4a have been structurally charac...

An innovative cooling technology based on a vectoring dual synthetic jet (DSJ) actuator is proposed, and then flow field and heat transfer characteristics are experimentally investigated. The deflection angle of vectoring DSJ can vary bilaterally and linearly with the movement of the adjustable slide. This novel feature makes the installation more flexible to obtain a maximum heat transfer coefficient and the effective heat transfer area is greatly extended, comparing to a conventional DSJ. The sweeping-flow capability can prevent the marginal region from working continuously at a high temperature. This cooling technology is expected to have important practical implications in space-constrained and large-area electronic cooling. Moreover, a model predicting the heat-transfer influence domain is established based on the vectoring angle of DSJ. The predicted results are validated to be in good agreement with the experimental results in the normal impingement region and the cross-flow region. It can provide a guide for properly arranging electric devices to improve the convective heat transfer.

A series of ((pyridinyl)-1H-pyrazolyl)pyridine (pypzpy) ligands in which the pyrazolyl ring at 1- and 3-positions is modified by two 2-, 3-, or 4-pyridyl groups were prepared. Reaction of CuI with 2-(1-(pyridin-2-yl)-1H-pyrazolyl)pyridine (2,2′-pypzpy) in MeCN at room temperature or solvothermal reaction of the same components at 120 °C afforded one binuclear complex [{(2,2′-pypzpy)Cu}(μ-I)]2 (1). Treatment of CuI with 3-(1-(pyridin-2-yl)-1H-pyrazolyl)pyridine (3,2′-pypzpy) at room temperature or at 120 °C produced one-dimensional (1D) polymer [{Cu3(μ3-I)3}(μ-3,2′-pypzpy)]n (2) and one two-dimensional (2D) polymer [{Cu2(μ-I)(μ3-I)}2(3,2′-pypzpy)2]n (3), respectively. Similar reactions of CuI with 4-(1-(pyridin-2-yl)-1H-pyrazolyl)pyridine (4,2′-pypzpy) at room temperature or at 150 °C yielded one 1D polymeric complex [{Cu(μ3-I)}2(4,2′-pypzpy)2{Cu(μ-I)}2]n (4). Complexes [{Cu3(μ3-I)3}(μ-2,3′-pypzpy)]n (5), [(CuI)(μ-2,3′-pypzpy)]2 (6), [(Cu2I2)(3,3′-pypzpy)] (7), [(CuI)(4,3′-pypzpy)] (8), [{Cu(μ3-I)}2(μ-2,4′...

An experimental investigation is carried out to analyze the flow regime and impingement heat transfer of a dual synthetic jet (DSJ) actuator for the compact thermal management. The time-averaged flow field of DSJ is observed to consist of four regions, namely, the formation region, merging region, development region and decay region other than three regions of SJ without the merging region. The downstream vorticity-concentrated partitions of the SJ and the DSJ spread outwards at about 22.5° and 26.6°, respectively. The heat transfer characteristic of an impinging DSJ is analyzed by comparing with a synthetic jet (SJ). It is found that the local Nusselt number reaches a maximum at a same dimensionless impingement spacing of H/dh = 5.5 both for the SJ and the DSJ, and the maximum local Nusselt number of the impinging DSJ is 11.4% higher. The maximum area-averaged Nusselt number of the impinging DSJ is 8.6% higher at only half of H/dh than the impinging SJ, which is more preferable for the space-restricted electronic cooling. In addition, the effects of slot dimensions on the heat transfer of the impinging DSJ are studied. The peak Nusselt number is directly proportional to the slot neck length and inversely proportional to the slot aspect ratio at a same H/dh. The area-averaged Nusselt number reduces with the increase of the slot neck length at a smaller H/dh, and varies contrarily at a larger H/dh. The best heat transfer performance of the impinging DSJ is achieved at a midlevel aspect ratio. The results provide a design guideline for the cooling packages of space-restricted electronics.

Reactions of Zn(NO3)2 with tetrakis(4-pyridyl)cyclobutane (tpcb) and 1,4-benzenedicarboxylic acid (1,4-H2BDC), 4,4′-biphenyldicarboxylic acid (4,4′-H2BPDB), 5-methyl-1,3-benzenedicarboxylic acid (5-CH3-1,3-H2BDC), 1,3,5-benzenetricarboxylic acid (1,3,5-H3BTC), 5-amino-1,3-benzenedicarboxylic acid (5-NH2-1,3-H2BDC), 4,4′-benzophenonedicarboxylic acid (4,4′-H2BPNDB) under solvothermal conditions led to the formation of six polydimensional coordination polymers {[Zn5(1,4-BDC)5(tpcb)2.5]·5H2O}n (1), {[Zn2(4,4′-BPDB)2(tpcb)]·0.5MeCN}n (2), [Zn2(OH2)2(5-CH3-1,3-BDC)2(tpcb)]n (3), {[Zn2(1,3,5-HBTC)2(tpcb)]·H2O}n (4), {[Zn2(5-NH2-1,3-BDC)2(tpcb)·H2O]}n (5), and [Zn2(4,4′-BPNDB)2(tpcb)]n (6). Compounds 1–6 were characterized by elemental analysis, IR, powder X-ray diffraction, and single crystal X-ray diffraction. Compounds 1 and 6 have different 3D (4,4) connected structures. Compounds 2–4 have different two-fold interpenetrating 3D (4,4)-connected structures. Compound 5 holds a 2D (3,4)-connected structure. The solid state luminescent properties of compounds 1–6 at ambient temperature were also investigated. The results provided some interesting insights into ligand effects on the structures and luminescent properties of zinc(II) coordination polymers.