Automatic vectorization of point symbols on archive maps using deep convolutional neural network

Archive topographical maps are a key source of geographical information from past ages, which can be valuable for several science fields. Since manual digitization is usually slow and takes much human resource, automatic methods are preferred, such as deep learning algorithms. Although automatic vectorization is a common problem, there have been few approaches regarding point symbols. In this paper, a point symbol vectorization method is proposed, which was tested on Third Military Survey map sheets using a Mask Regional Convolutional Neural Network (MRCNN). The MRCNN implementation uses the ResNet101 network improved with the Feature Pyramid Network architecture and is developed in a Google Colab environment. The pretrained network was trained on four point symbol categories simultaneously. Results show 90% accuracy, while 94% of symbols detected for some categories on the complete test sheet.

Four Novel d10 Metal-Organic Frameworks Incorporating Amino-Functionalized Carboxylate Ligands: Synthesis, Structures, and Fluorescence Properties

By employment of amino-functionalized dicarboxylate ligands to react with d10 metal ions, four novel metal-organic frameworks (MOFs) were obtained with the formula of {[Cd(BCPAB)(μ2-H2O)]}n (1), {[Cd(BDAB)]∙2H2O∙DMF}n (2), {[Zn(BDAB)(BPD)0.5(H2O)]∙2H2O}n (3) and {[Zn(BDAB)(DBPB)0.5(H2O)]∙2H2O}n (4) (H2BCPAB = 2,5-bis(p-carbonylphenyl)-1-aminobenzene; H2BDAB = 1,2-diamino-3,6-bis(4-carboxyphenyl)benzene); BPD = (4,4′-bipyridine); DBPB = (E,E-2,5-dimethoxy-1,4-bis-[2-pyridin-vinyl]-benzene; DMF = N,N-dimethylformamide). Complex 1 is a three-dimensional (3D) framework bearing seh-3,5-Pbca nets with point symbol of {4.62}{4.67.82}. Complex 2 exhibits a 4,4-connected new topology that has never been reported before with point symbol of {42.84}. Complex 3 and 4 are quite similar in structure and both have 3D supramolecular frameworks formed by 6-fold and 8-fold interpenetrated 2D coordination layers. The structures of these complexes were characterized by single crystal X-ray diffraction (SC-XRD), thermal gravimetric analysis (TGA) and powder X-ray diffraction (PXRD) measurements. In addition, the fluorescence properties and the sensing capability of 2–4 were investigated as well and the results indicated that complex 2 could function as sensor for Cu2+ and complex 3 could detect Cu2+ and Ag+via quenching effect.

Seven new metal–organic frameworks assembled from semi-rigid polycarboxylate and auxiliary N-donor ligands: syntheses, structures and properties

Seven new metal–organic frameworks (MOFs), namely, [Zn2(L 1)(H2O)3] n (1), [Zn2(L 1)(dib)(H2O)2] n (2), {[Zn2(L 1)(4,4′-bipy)(H2O)2]·H2O} n (3), [Cd2(L 1)(1,10-phen)] n (4), [Ni2(HL 1)(4,4′-bipy)(μ3-OH)(μ2-H2O)] n (5), {[Co4(L 1)(4,4′-bibp)3]·(4,4′-bibp)3} n (6), and [Co2(L 2)(4,4′-bibp)2(H2O)] n (7), where H4 L 1 and H4 L 2 are semi-rigid 3-(3,5-dicarboxylphenoxy)phthalic acid and 4-(3,5-dicarboxylphenoxy)phthalic acid, respectively, and 4,4′-bipy is 4,4′-bipyridine, dib is 1,4-bis(1H-imidazol-1-yl)benzene, 1,10-phen is 1,10-phenanthroline and 4,4′-bipb is 1,4-bis(pyridin-4-yl)benzene, have been prepared under solvothermal conditions with ZnII, CdII, CoII and NiII ions in the presence of auxiliary N-donor ligands. The crystal structures and photoluminescence and magnetic properties of these compounds have been investigated. Compound 1 displays a 3,4,6-connected two-dimensional (2D) topology with a Schläfli symbol of (42.5)2(43.52.7)(45.56.63)2, and the 2D structure was further assembled to form a three-dimensional (3D) framework by intermolecular O—H...O hydrogen bonds. Compound 2 features a novel 3,3,4-connected structure and the point symbol is (4.102)(4.6.84)(62.8). Compound 3 exhibits a 3,4,6-connected 3-nodal net having a 3,4,6 T53 type topology, with the point symbol (4.62)2(42.64)2(42.68.82.103). Compound 4 shows a 2D→3D supramolecular structure formed by π–π stacking interactions. Compound 5 possesses a 3D framework with a tfz-d net topology. Compounds 6 and 7 are constructed from the same auxiliary ligand and metal salt at the same temperature, but with different main ligands and exhibiting different topologies. Compound 6 presents a 3D 4,6-connected topological network with a Schläfli symbol of (3.44.6)(32.44.56.63), while compound 7 has a 3D topological network with a Schläfli symbol of (412.616). Magnetic analyses indicate that compounds 5 and 7 show weak antiferromagnetic interactions.

A novel three-dimensional tetranuclear CoII coordination polymer with water hexamers based on the V-shaped tetracarboxylate ligand 4-(2,4-dicarboxylatophenoxy)phthalate

A new coordination polymer (CP), namely, poly[[diaquatris[μ2-1,4-bis(1H-imidazol-1-yl)benzene]bis[μ6-4-(2,4-dicarboxylatophenoxy)phthalato]tetracobalt(II)] hexahydrate], {[Co4(C16H6O9)2(C12H10N4)3(H2O)2]·6H2O} n , has been synthesized by solvothermal reaction. The CP was fully characterized by IR spectroscopy, elemental analysis, thermogravimetric analysis, and powder and single-crystal X-ray diffraction. It presents a three-dimensional (3D) structure based on tetranuclear CoII secondary building units (SBUs) with a tfz-d net and point symbol (43)2(46·618·84). The 4-(2,4-dicarboxyphenoxy)phthalic acid (H4dcppa) ligands are completely deprotonated and link {Co4(COO)4}4− SBUs into two-dimensional (2D) layers. Furthermore, adjacent layers are connected by 1,4-bis(1H-imidazol-1-yl)benzene (bib) ligands, giving rise to a 3D supramolecular architecture. Interestingly, there are numerous elliptical cavities in the CP where isolated unique discrete hexameric water clusters have been observed. The results of thermogravimetric and magnetic analyses are described in detail.

Map Hacking: On the use of inverse address-matching to discover individual identities from point-mapped information sources

The widespread availability of low-cost desktop GIS software now enables an unprecedented number of individuals to produce point-symbol maps from information considered confidential in its original, tabular, form. These maps, which are made by address-matching individual-level administrative records to street centerline files (e.g. TIGER) can be easily (and perhaps inadvertently) distributed in HTML format. These “raw” maps comprised of abstract map symbols do not directly disclose confidential information. However, a determined data spy can use GIS technology and other knowledge to “hack” the maps and make an estimate of the actual address (and hence, a good guess as the identity of an individual) associated with each point symbol. Though this process, called inverse address-matching, is supported by widely available GIS software, there has been almost no discussion in the GIS literature about factors that are important in successfully inverting the address-matching transformation. In this paper, we situate our work within current debates on privacy, and then conduct a set of controlled experiments that are designed to evaluate the performance of the address inversion process. We do this with the full understanding that such knowledge could be used for nefarious purposes. Such knowledge, however, can also be used to guard against individual-level identity disclosure by guiding the design and use of effective cartographic masking techniques.

A Co-MOF with a (4,4)-connected binodal two-dimensional topology: synthesis, structure and photocatalytic properties

The Co-MOF poly[[diaqua{μ4-1,1,2,2-tetrakis[4-(1H-1,2,4-triazol-1-yl)phenyl]ethylene-κ4 N:N′:N′′:N′′′}cobalt(II)] benzene-1,4-dicarboxylic acid benzene-1,4-dicarboxylate], {[Co(C34H24N12)(H2O)2](C8H4O4)·C8H6O4} n or {[Co(ttpe)(H2O)2](bdc)·(1,4-H2bdc)} n , (I), was synthesized by the hydrothermal method using 1,1,2,2-tetrakis[4-(1H-1,2,4-triazol-1-yl)phenyl]ethylene (ttpe), benzene-1,4-dicarboxylic acid (1,4-H2bdc) and Co(NO3)2·6H2O, and characterized by single-crystal X-ray diffraction, IR spectroscopy, powder X-ray diffraction (PXRD), luminescence, optical band gap and valence band X-ray photoelectron spectroscopy (VB XPS). Co-MOF (I) shows a (4,4)-connected binodal two-dimensional topology with a point symbol of {44·62}{44·62}. The two-dimensional networks capture free neutral 1,4-H2bdc molecules and bdc2− anions, and construct a three-dimensional supramolecular architecture via hydrogen-bond interactions. MOF (I) is a good photocatalyst for the degradation of methylene blue and rhodamine B under visible-light irradiation and can be reused at least five times.

Organically pillared layer framework of [Eu(NH2–BDC)(ox)(H3O)]

The non-porous three-dimensional structure of poly[(μ5-2-aminobenzene-1,4-dicarboxylato)(μ6-oxalato)(oxomium)europium(III)], [Eu(C8H5NO4)(C2O4)(H3O)] n or [EuIII(NH2–BDC)(ox)(H3O)] n (NH2–BDC2− = 2-aminoterephthalate and ox2− = oxalate) is constructed from two-dimensional layers of EuIII–carboxylate–oxalate, which are connected by NH2–BDC2− pillars. The basic structural unit of the layer is an edge-sharing dimer of TPRS-{EuIIIO9}, which is assembled through the ox2− moiety. The intralayer void is partially occupied by TPR-{EuIIIO6} motifs. Weak C—H...O and strong, classical intramolecular N—H...O and intermolecular O—H...O hydrogen-bonding interactions, as well as weak π–π stacking interactions, affix the organic pillars within the framework. The two-dimensional layer can be simplified to a uninodal 4-connected sql/Shubnikov tetragonal plane net with point symbol {44.62}.

Construction of (3,8)-connected three-dimensional cobalt(II) and copper(II) coordination polymers with 1,3-bis[(1,2,4-triazol-4-yl)methyl]benzene and benzene-1,3,5-tricarboxylate ligands

Coordination polymers (CPs) have been widely studied because of their diverse and adjustable topologies and wide-ranging applications in luminescence, chemical sensors, magnetism, photocatalysis, gas adsorption and separation. In the present work, two coordination polymers, namely poly[(μ5-benzene-1,3,5-tricarboxylato-κ6 O 1:O 1′:O 3:O 3:O 5,O 5′){μ3-1,3-bis[(1,2,4-triazol-4-yl)methyl]benzene-κ3 N:N′:N′′}di-μ3-hydroxido-dicobalt(II)], [Co2(C9H3O6)(OH)(C12H12N6)] n or [Co2(btc)(OH)(mtrb)] n , (1), and poly[[diaquabis(μ3-benzene-1,3,5-tricarboxylato-κ3 O 1:O 3:O 5)bis{μ3-1,3-bis[(1,2,4-triazol-4-yl)methyl]benzene-κ3 N:N′:N′′}tetra-μ3-hydroxido-tetracopper(II)] monohydrate], {[Cu4(C9H3O6)2(OH)2(C12H12N6)2(H2O)2]·H2O} n or {[Cu4(btc)2(OH)2(mtrb)2(H2O)2]·H2O} n , (2), were synthesized by the hydrothermal method using 1,3-bis[(1,2,4-triazol-4-yl)methyl]benzene (mtrb) and benzene-1,3,5-tricarboxylate (btc3−). CP (1) exhibits a (3,8)-coordinated three-dimensional (3D) network of the 3,8T38 topological type, with a point symbol of {4,5,6}2{42·56·616·72·82}, based on the tetranuclear hydroxide cobalt(II) cluster [Co4(μ3-OH)2]. CP (2) shows a (3,8)-coordinated tfz-d topology, with a point symbol of {43}2{46·618·84}, based on the tetranuclear hydroxide copper(II) cluster [Cu4(μ3-OH)2]. The different (3,8)-coordinated 3D networks based on tetranuclear hydroxide–metal clusters of (1) and (2) are controlled by the different central metal ions [CoII for (1) and CuII for (2)]. The thermal stabilities and solid-state optical diffuse-reflection spectra were measured. The energy band gaps (E g) obtained for (1) and (2) were 2.72 and 2.29 eV, respectively. CPs (1) and (2) exhibit good photocatalytic degradation of the organic dyes methylene blue (MB) and rhodamine B (RhB) under visible-light irradiation.

Cadmium(II) three-dimensional coordination polymers constructed from 1,3,5-tris(4-carboxyphenoxy)benzene: synthesis, crystal structure, fluorescence and I2 sorption characterization

Two three-dimensional (3D) CdII coordination polymers, namely poly[[di-μ-aqua-diaquabis{μ5-4,4′,4′′-[benzene-1,3,5-triyltris(oxy)]tribenzoato}tricadmium(II)] dihydrate], {[Cd3(C27H15O9)2(H2O)4]·2H2O} n , (I), and poly[[aqua{μ6-4,4′,4′′-[benzene-1,3,5-triyltris(oxy)]tribenzoato}(μ-formato)[μ-1,1′-(1,4-phenylene)bis(1H-imidazole)]dicadmium(II)] dihydrate], {[Cd2(C27H15O9)(C12H10N4)(HCOO)(H2O)]·2H2O} n , (II), have been hydrothermally synthesized from the reaction system containing Cd(NO3)2·4H2O and the flexible tripodal ligand 1,3,5-tris(4-carboxyphenoxy)benzene (H3tcpb) via tuning of the auxiliary ligand. Both complexes have been characterized by single-crystal X-ray diffraction analysis, elemental analysis, IR spectra, powder X-ray diffraction and thermogravimetric analysis. Complex (I) is a 3D framework constructed from trinuclear structural units and tcpb3− ligands in a μ5-coordination mode. The central CdII atom of the trinuclear unit is located on a crystallographic inversion centre and adopts an octahedral geometry. The metal atoms are bridged by four syn–syn carboxylate groups and two μ2-water molecules to form trinuclear [Cd3(COO)4(μ2-H2O)2] secondary building units (SBUs). These SBUs are incorporated into clusters by bridging carboxylate groups to produce pillars along the c axis. The one-dimensional inorganic pillars are connected by tcpb3− linkers in a μ5-coordination mode, thus forming a 3D network; its topology corresponds to the point symbol (42.62.82)(44.62)2(45.66.84)2. In contrast to (I), complex (II) is characterized by a 3D framework based on dinuclear cadmium SBUs, i.e. [Cd2(COO)3]. The two symmetry-independent CdII ions display different coordinated geometries, namely octahedral [CdN2O4] and monocapped octahedral [CdO7]. The dinuclear SBUs are incorporated into clusters by bridging formate groups to produce pillars along the c axis. These pillars are further bridged either by tcpb3− ligands into sheets or by 1,4-bis(imidazol-1-yl)benzene ligands into undulating layers, and finally these two-dimensional surfaces interweave, forming a 3D structure with the point symbol (4.62)(47.614). Compound (II) exhibits reversible I2 uptake of 56.8 mg g−1 with apparent changes in the visible colour and the UV–Vis and fluorescence spectra, and therefore may be regarded as a potential reagent for the capture and release of I2.