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Multi-cavity mold design is an efficient approach to achieving mass production and is frequently used in plastic injection applications. The runner system of a multi-cavity mold delivers molten plastic to each cavity evenly and makes the molded product from each individual cavity possess an equivalent quality. Not only the dimensions, but also the invisible quality, e.g., the internal stress of the product is of great concern in regard to molding quality. Using commercial software to find an optimal solution for the runner system may be time-consuming in respect to iterations if the engineers lack empirical rules. The H-type runner system is often used due to an inherently balanced filling in multi-cavities. However, the shear heat inducing an imbalanced flow behavior requires the H-type runner system to be improved as the number of the cavities is increased. This work develops a methodology based on the rheological concept to determine the runner system of a multi-cavity mold semi-analytically. As the relation of the viscosity with respect to shear rate is known, the runner system can be constructed step-by-step via this method. The use of the proposed method helps to focus attention on the connection between the physical situation and its related mathematical model. The influences of the melt temperature and resin type can be easily investigated. Three design examples, a 16-cavity mold with a fishbone runner system, an 8-cavity mold with an arbitrary runner layout, and the influences of melt temperature and resin type on the runner design are demonstrated and validated by the commercial software. The proposed method shows its great benefit when a new runner design project is launched in the initial design stage and then cooperates with the commercial software for further modifications.

To estimate the effect of bisphosphine ligands on the formation of the isomeric core structures of gold nanoclusters, the different ligation of bisphosphine ligands is usually used to participate in the construction of gold nanoclusters. Here, the selection of the different bisphosphine ligands, DPEphos and Xantphos, is performed to construct two novel gold nanoclusters, [Au11(DPEphos)4Cl2]Cl (1) and [Au11(Xantphos)4Cl2]Cl(2), which have been characterized by IR, 1H and 31P NMR, ESI-MS, XRD, SEM, XPS, TG, UV-vis, and X-ray crystal structure analysis. The structural analyses indicate that the ligation of bisphosphine ligands play a crucial role in the formation of the fascinating Au11 cores: gold nanocluster 1 includes a birdcage-shaped Au11 core with eight electrons, while gold nanocluster 2 contains a crown-shaped Au11 core with eight electrons. Meanwhile, DOS and PDOS studies indicate that the Au11 cores have a strong effect on the composition of HOMO and LUMO orbitals of gold nanoclusters. Furthermore, the different Au11 core structures lead to different optical absorption characteristics (1: 456 nm; 2: 427 nm). All these demonstrate that the ligation of bisphosphine ligands may have an important influence on constructing the stability of the isomeric core structures of gold nanoclusters.

To estimate the effect of bisphosphine ligands on the formation of the isomeric core structures of gold nanoclusters, the different ligation of bisphosphine ligands is usually used to participate in the construction of gold nanoclusters. Here, the selection of the different bisphosphine ligands, DPEphos and Xantphos, is performed to construct two novel gold nanoclusters, [Au

A series of copper(I)-diimine complexes, [Cu(bdpp)(bpy)]BF4 (1), [Cu(bdpp) (pen)]BF4 (2), [Cu(bdpp)(damp)]BF4 (3), [Cu(bdpp)(pen)]BF4 (4) (bdpp = 4,6-bis-(biphenyl phosphino) phenoxazine, bpy = 2,2′-bipyridine, phen = 1,10-Phenanthroline, dmp = 2,9-dimethyl-1,10-phenanthroline, bphen = 4,7-diphenyl-1,10-phenanthroline), have been synthesized and characterized by IR, 1H NMR, 31P NMR, XRD and X-ray crystal structure analysis. Structural analysis reveals that each Cu+ in 1–4 is four-coordinated by two N atoms and two P atoms and adopts a distorted tetrahedral geometry. DFT calculations show that the HOMOs in 1–4 are mainly comprised of bdpp and copper d–orbitals, while the LUMOs are mainly dominated by diimine ligands. Calculation of atomic charges indicates that the charges of the central Cu atoms in 1–4 are less than + 1, and the diimine ligands may be the key to the metal charge transfer to the coordinated atom. In 1–4, the maximum phosphorescent lifetimes and quantum yields are up to 349 μs and 22%, respectively. Moreover, complex 3 is used for fabricating the LED device, showing a decent performance with the maximum EQE of 11%.

A mononuclear Cu(I) complex, Cu(dppb)(2,2′-biquinoline)]BF4(1) (dppb = 1, 2-bis(diphenyl phosphino)benzene), has been synthesized and characterized at 100 K, 150 K, 200 K, 250 K and 298 K. The structural analysis reveals that the rise of temperature from 100 K to 298 K leads to the increasement of molecular size, such as the unit-cell parameters and volume, and the change of bond lengths, bond angles, C H…π and π…π interactions. DFT calculations indicate that the HOMO → LUMO energy gap and Mulliken atomic charges are changed by the increase of temperature from 100 K to 298 K, and the component of the HOMOs and LUMOs are barely changed at 100–298 K, which is in accordance with the variation of DOS and PDOS at different temperatures. Meanwhile, the surprising broad blue-yellow excitation bands are observed at 100–298 K and the maximum emission is increasing with the blue shift from 735 nm at 100 K to 685 nm at 298 K. Furthermore, the emission decay time of complex 1 reaches 3 μs at 298 K. In addition, copper(I) complex 1 is used to fabricate the monochromatic LED, which emits a red light.

Three Cu(I) complexes, [Cu(dppb)(bbim)]BF4 (1), [Cu(DPEphos)(bbim)]BF4 (2) and [Cu (Xantphos)(bbim)]BF4 (3) (dppb =1, 2-bis(diphenylphosphino)benzene, DPEphos=bis(2-diphenyl phosphinophenyl)ether, Xantphos=9, 9-dimethyl-bis(diphenylphosphino)xanthenes, bbim = bisbenzimidazole), have been synthesized and characterized by IR, 1H NMR, 31P NMR, TG, XRD elemental analysis and X-ray crystal structure analysis. The structural analysis indicates that the increases in the temperature from 100 K to 300 K result in the change of bond lengths, bond angles and the weak interactions. Theoretical calculations demonstrate that the HOMO → LUMO energy gap and Mulliken atomic charges are increased or shorten by increasing temperature from 100 K to 300 K, in according with the change of bond lengths and angles, while the composition of HOMO and LUMO orbitals are nearly unchanged at different temperatures. Meanwhile, the solid-state luminescent properties of these copper(I) complexes at 100 K, 200 K and 300 K also exhibit that the change of temperature leads to the variation of the Kr, Knr, τ, Фem and λmax, having a certain degree of consistency with the related calculation results. In these complexes, the maximum phosphorescent lifetime and quantum yield are up to 309 μs and 23% at 300 K, respectively. Moreover, to estimate potential application of copper(I) complexes for LED, monochromatic and white LED have been fabricated, respectively, showing reasonable electroluminescence with the maximum external quantum efficiency 3.95% and 5.31%.

Reaction of copper(I) salt with 2, 2′-bipyridine in different solvent produced two Cu4O4-based coordination complexes [Cu4(2,2′-bipyridine)4(OH)4(BF4)2](BF4)2. •2DMF (1) and {[Cu4 (2,2′-bipyridine)4(OH)4(BF4)2] (BF4)2 • 2{[Cu4(2,2′-bipyridine)4 (OH)4(BF4)](BF4)3}(2). Structural analysis shows that the Cu4O4 cores in 1 are interconnected by four OH− anions in the μ2-O and μ3-O coordination modes and four 2,2′-bipyridine in a bidentate mode to form a ladder-like conformation, while the Cu4O4 cores in 2 are linked by ligands OH− (ladder-like: μ2-O and μ3-O; cage-like: μ3-O) and bipyridine to yield two different conformations, and the Cu atoms also form different kinds of weak Cu … π interactions with the Cu … πcentroid distances of 3.415–3.664 A in 1, and 3.501–3.667 A in 2. DFT studies indicate the stability may be 1 > 2, and the HOMOs is collaboratively contributed by the Cu4O4 cores with admixed BF4− character, while the LUMOs is mainly localized on the copper d-orbital with admixed O atoms. In addition, calculation of atomic charges by the Mulliken method display that the charges of the central Cu atoms are less than +2, and the anion BF4 may be the key to the metal transfers charge to the coordinated atom.