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Two new three-dimensional (3D) Ni(II) coordination polymers (CPs), namely, {[Ni(L1)2(H2O)2]·(1,5-NDS)}n (1) and [Ni(L2)2(1,5-NDS)]n (2) have been hydrothermally synthesized based on 1,5-naphthalenedisulfonate (1,5-NDS) and two bis(benzimidazole) ligands (L1 = 1,4-bis(1H-benzimidazol-1-yl)butane, L2 = 1,2-bis(benzimidazol-1-ylmethyl)benzene). CP 1 presents a 3D framework with 4-connected 66dia topology. While CP 2 shows a 3D network with 6-connected (412.63) pcu topology. CPs 1 and 2 both exhibit excellent luminescent properties and good water stability. And luminescent sensing experiments reveal that both CPs can detect uric acid (UA) in aqueous solution through the luminescent quenching effect, and they also can detect tryptophan (Trp) in aqueous solution with red-shift and turn-on luminescent effect. The detection limits toward UA and Trp are 1.30 and 0.92 μM for 1, and those are 1.20 and 1.30 μM for 2, respectively. Furthermore, the luminescence sensing mechanisms were studied via PXRD patterns, UV–Vis spectra, lifetimes and theoretical calculations. The luminescence test films of 1 and 2 were also prepared for visual detection of UA and Trp. [ABSTRACT FROM AUTHOR]

Two Cd(II) MOFs based on the 1,4-bis[(2-methyl-1H-imidazol-1-yl)-methyl]benzene (1,4-mbix) and succinate (Suc2−) or azelate (Aze2−) ligands have been hydrothermally synthesized, namely, {[Cd2(Suc)2(1,4-mbix)2]·5H2O}n (1) and [Cd(Aze)(1,4-mbix)]n (2). Both MOFs were structurally characterized by single-crystal X-ray diffraction. In MOF 1, the Cd(II) centers are connected by Suc2− and 1,4-mbix to generate a two-dimensional (2D) sql layer with (H2O)5 water cluster. Each 2D layer is further interlocked with two adjacent layers to form a 2D + 2D → 3D parallel polycatenated structure. In MOF 2, when the Suc2− was placed by Aze2−, the Cd(II) centers are connected by Aze2− and 1,4-mbix into a 2D sql layer but without any water molecules. And two 2D sql layers interpenetrate with each other to generate a twofold 2D + 2D → 2D sheet. MOFs 1 and 2 display photoluminescence at 343 nm (λex = 288 nm) and 298 nm (λex = 271 nm), respectively. Luminescent quenching experiments show that 1 and 2 have good ability for detection of Fe3+ in deionized water with low detection limits as 0.58 μM for 1 and 0.54 μM for 2, respectively. Two MOFs also can serve as luminescent sensors for Fe3+ in real tap water and river water. The luminescent quenching of 1 and 2 toward Fe3+ can be attributed to the competition among the absorption of Fe3+ with the excitation and emission of two MOFs. [ABSTRACT FROM AUTHOR]

The interaction between soil and marine structures like submarine pipeline/pipe pile/suction caisson is a complicated geotechnical mechanism process. In this study, the interface is discretized into multiple mesoscopic contact elements that are damaged randomly throughout the shearing process due to the natural heterogeneity. The evolution equation of damage variable is developed based on the Weibull function, which is able to cover a rather wide range of distribution shapes by only two parameters, making it applicable for varying scenarios. Accordingly, a statistical damage model is established by incorporating Mohr–Coulomb strength criterion, in which the interfacial residual strength is considered whereby the strain softening behavior can be described. A concept of "semi-softening" characteristic point on shear stress–displacement curve is proposed for effectively modeling the evolution of strain softening. Finally, a series of ring shear tests of the interfaces between fine sea sand and smooth/rough steel surfaces are conducted. The predicted results using the proposed model are compared with experimental data of this study as well as some results from existing literature, indicating that the model has a good performance in modeling the progressive failure and strain softening behavior for various types of soil–structure interfaces. [ABSTRACT FROM AUTHOR]

Many existed quantum private comparison (QPC) protocols can determine whether two secrets are equal or not, while the quantum private magnitude comparison (QPMC) protocol by Lang can output three results: greater than, equal and less than for two private data. In order to implement the magnitude comparison, it defined the minimum operation. However, if we only rely on this operation to implement QPMC, it may not be efficient at cooperating with some quantum resources. For this reason, it is necessary for us to introduce another operation—maximum one. With regard to some quantum resources, only by using the maximum operation are we able to realize a simple and efficient QPMC. In this paper, it is the maximum operation that helps us utilize a single Bell state to propose a QPMC protocol in an easy and efficient way. The protocol is fully analysed for its correctness and security. The analyses prove that the presented protocol is not only simple yet efficient but also of low costs. It would be a better alternative for QPMC. [ABSTRACT FROM AUTHOR]

Two new heterometallic CuEr cluster complexes based on 3,5-dichlorobenzoic acid (HL) and 2,2′:6′,2″-terpyridine (TPY), [Cu(L)(TPY)][Er(L)4]·H2O (1) and [Cu(L)(TPY)][Er2(L)7] (2), have been hydrothermally prepared by controlling the metal–ligand ratios. Comparative study revealed that metal–ligand ratios affected the coordination modes of L− and thus generate two distinct structures. Both complexes display as ion-pair bicomponent structures. The cationic [Cu(L)(TPY)]+ components show the similar binuclear cluster structure in two complexes, while the two anionic parts are very different. In 1, two Er(III) centers are coordinated by four bridging and four chelating L− ligands to form the binuclear anionic [Er2(L)8]2− cluster. While in 2, all L− ligands show the bridging modes and connect the Er(III) centers into an extended one-dimensional (1D) chain. So the overall structures of 1 and 2 are bicomponent 0D + 0D and 0D + 1D structures, respectively. Direct current magnetic susceptibility measurements were performed for two complexes and they both showed antiferromagnetic behavior. [ABSTRACT FROM AUTHOR]

Based on a synthetic geological study of drilling, well logging and core observations, two main genetic types of Chang 9 sand body in Odors Basin were recognized, which included two effects, that is, delta environment and tractive current effects that lead to the development of mouth bar, distal bar, sheet sand and other sand bodies of subaerial and subaqueous distributary channel, natural levee, flood fan and delta front, and shore-shallow lake environment and lake flow transformation effects that result in the development of sandy beach bar, sheet sand and other sand bodies. Chang 9 sand body mainly developed five basic vertical structures, namely box shape, campaniform, infundibuliform, finger and dentoid. The vertical stacking patterns of multilayer sand body was complex, and the common shapes included box shape + box shape, campaniform + campaniform, campaniform + box shape, infundibuliform + infundibuliform, campaniform + infundibuliform, box shape + campaniform, box shape + infundibuliform, and finger + finger. Based on the analysis on major dominating factors of vertical structure of sand body, sedimentary environment, sedimentary facies and rise, fall and cycle of base level are identified as the major geological factors that control the vertical structure of single sand body as well as vertical stacking patterns and distribution of multistory sand bodies. [ABSTRACT FROM AUTHOR]

Two Cd(II) MOFs based on the 1,4-bis[(2-methyl-1H-imidazol-1-yl)-methyl]benzene (1,4-mbix) and succinate (Suc2−) or azelate (Aze2−) ligands have been hydrothermally synthesized, namely, {[Cd2(Suc)2(1,4-mbix)2]·5H2O}n (1) and [Cd(Aze)(1,4-mbix)]n (2). Both MOFs were structurally characterized by single-crystal X-ray diffraction. In MOF 1, the Cd(II) centers are connected by Suc2− and 1,4-mbix to generate a two-dimensional (2D) sql layer with (H2O)5 water cluster. Each 2D layer is further interlocked with two adjacent layers to form a 2D + 2D → 3D parallel polycatenated structure. In MOF 2, when the Suc2− was placed by Aze2−, the Cd(II) centers are connected by Aze2− and 1,4-mbix into a 2D sql layer but without any water molecules. And two 2D sql layers interpenetrate with each other to generate a twofold 2D + 2D → 2D sheet. MOFs 1 and 2 display photoluminescence at 343 nm (λex = 288 nm) and 298 nm (λex = 271 nm), respectively. Luminescent quenching experiments show that 1 and 2 have good ability for detection of Fe3+ in deionized water with low detection limits as 0.58 μM for 1 and 0.54 μM for 2, respectively. Two MOFs also can serve as luminescent sensors for Fe3+ in real tap water and river water. The luminescent quenching of 1 and 2 toward Fe3+ can be attributed to the competition among the absorption of Fe3+ with the excitation and emission of two MOFs. [ABSTRACT FROM AUTHOR]