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Incarcerated gravid uterus is a rare obstetric condition that contributes to pregnancy-related adverse outcomes, especially if the uterus remains incarcerated and the condition goes undiagnosed until delivery. An effective diagnosis of this condition is benefited from pelvic examination combined with imaging methods and based on suspected symptoms. We present a case of ultrasound-assisted instrument reposition of an incarcerated gravid uterus at mid-gestation and discuss its clinical characteristics, diagnosis, imaging features, and treatment. We believe that once manual reduction fails, the use of instruments will undoubtedly be a better choice.

Electronic effect and geometry distortion of a low-symmetry ligand-field on the anisotropy barrier of spin reversal have been compared in three Dy(iii) single-ion magnets through simultaneous binding of heterodonor chelating ligands.

In recent decades, nanomaterial-based artificial enzymes called nanozymes have received more and more attention and have been applied in biological, chemical, medical, and other fields. In this work, bimetallic FeMn@C was synthesized by calcination from the Prussian blue analogue. The synthesized bimetallic FeMn@C exhibits efficient peroxidase-like activity. The effect of Mn doping amount, catalytic kinetics, and mechanism of FeMn@C nanozyme was further studied in detail. The results show that the peroxidase-like activity of bimetallic FeMn@C is nearly 16 times higher than that of single-metal Fe@C. The peroxidase-like activity of FeMn@C originates from its production of radicals. Compared with natural enzymes, FeMn@C nanozyme has a better affinity for the substrates. Besides, FeMn@C nanozyme has better stability than natural enzymes. Because of its strong magnetism, FeMn@C nanozyme can be recycled easily and exhibits excellent recycling performance. Based on the good affinity of FeMn@C for H

One mononuclear complex [Dy(Htpy)(NO3)2(acac)] (1) and a tpy--extended 1D chain {[Dy(CH3OH)(NO3)2(tpy)]·CH3OH}n (2) (Htpy = 4'-(4-hydroxyphenyl)-2,2':6',2''-terpyridine, Hacac = acetylacetone) were successfully designed to investigate the effect of bond length tuning around the DyIII cation on the magnetic dynamics of single-molecule magnets (SMMs). Interestingly, two magnetic entities possess the same local coordination sphere (N3O6-donor) as well as the configuration (Muffin, Cs) of dysprosium centers. Only a slight difference in structure results from purposefully substituting the acetylacetone ligand in 1 with hydroxyl oxygen from tpy- linkage and one methanol molecule in 2. However, the remarkable differences in dynamics behavior were clearly found between them. Compound 1 possesses a thermal-activated effective energy barrier (Ueff/kB) of 22.7 K under a 0 kOe direct current (dc) field and negligible hysteresis loop at 2.0 K, while complex 2 shows high-performance SMM behavior with the largest energy barrier of 354.36 K among the reported nine-coordinated DyIII-based systems and the magnetic hysteresis up to 4.0 K at a sweep rate of 200 Oe s-1. These experimental results combined with the previous reported data reveal that the shortest bond and the bond length difference around the DyIII center synergistically determine the dynamics of SMMs. The uniaxial anisotropy increases with the decrease of the shortest bond and the increase of the bond length difference, which is confirmed by the theoretical calculations.

A versatile microporous metal-organic framework (MOF), {[Cu(TIA)]·1.5CH3OH}n (Cu-1), was successfully obtained via the solvothermal reaction of cuprous(II) salt with the bifunctional ligand 3-(1H-1,2,4-triazol-1-yl)isophthalic acid. Single-crystal X-ray diffraction studies indicate that Cu-1 contains an apo three-dimensional skeleton and two types of one-dimensional channels. The framework of Cu-1 has excellent acid-alkali resistance and thermal stability, which is stable in a pH = 2-13 aqueous solution and an 260 °C air environment. In addition, the microporous copper MOF shows very high uptakes of CO2 (180 cm3·g-1) and C2H2 (113 cm3·g-1) at 273 K and displays excellent adsorption selectivity for small molecular gases. The ideal adsorbed solution theory selectivity values for C2H2/C2H4, CO2/CH4, and CO2/N2 are 2, 9, and 22 at 298 K, respectively. At the same time, breakthrough experiments for CO2/CH4, CO2/N2, and C2H2/C2H4 were further conducted to verify the efficient separation performances.

Constructing highly active electrocatalysts towards hydrogen evolution reaction (HER) in both alkaline and acidic media is essential for achieving a sustainable energy economy. Here, a facile ethylene glycol reduction strategy was employed to design the nickel-ruthenium nanocrystals (Ni-Ru NC) with an exposed highly active Ru (101) facet as an efficient electrocatalyst for HER. Testings show Ni-Ru NC outperforms the benchmark catalyst Pt/C by delivering extraordinarily low overpotentials of 21.1 and 70.9 mV to drive 10 mA cm

Photodegradation of organic dyes over coordination polymer (CP) photocatalysts has become one of the effective strategies for the prevention and control of water pollution, in which the energy band...

Three new Co(II) coordination polymers {[Co(TTPA)·(H2O)2]·H2O}n (Co-1), {[Co3(TTPA)3(H2O)2]·4DMSO}n (Co-2), and {[Co(TTPA)·(H2TTPA)]·2DMSO}n (Co-3) were successfully synthesized based on a multidentate bridging organic ligand 2,5-bis-(1,2,4-triazol-1-yl)-terephthalic acid (H2TTPA) under solvent-controlled thermal reaction conditions. Single-crystal X-ray diffraction studies show that complex Co-1 has a 4,4-linked two-dimensional layered structure, which is formed in a H2O–DMF–methanol mixed solvent. Co-2 displays a novel complicated topology—a 4,4,5,6-c tetranodal 3D framework with 1D channels along the a direction and is obtained under the condition of an equal volume ratio of DMSO and methanol as a solvent. Co-3 presents another 3D porous framework with a 4,6-dinodal 3D framework with a pore volume of 36.3% and is synthesized under the volume ratio of DMSO to methanol of 3 : 1. In addition, the static and/or dynamic magnetic properties of the three polymers were determined. The microporous MOF Co-2 also underwent gas sorption measurements.

In this work, an Fe3O triangle based helical chain complex [Fe3(μ3-O)(μ-O2CH)6H2O] was assembled in a solvothermal reaction. The complex was a rare polymeric complex bearing charge separation of Fe3+ and Fe2.5+, in which the charge distribution was like that of magnetite. The valence distribution and polymeric nature result in various magnetism behaviours e.g., ferrimagnetism along the chain, canted antiferromagnetic order, spin-flop and field induced SCM like behavior at low temperature.

Two new complexes, Ln(hfac)3(NITPhOA)2 (Ln = Tb(1), Dy(2); NITPhOA = 2-(4′-amyloxyphenyl)−4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide; hfac = hexafluoroacetylacetonate) have been synthesized and characterized. Single crystal X-ray diffraction analysis reveals that both complexes show mononuclear tri-spin structures. The central Ln(III) ion is eight-coordinated by three hfac anions and two NITPhOA molecules, in which the NITPhOA radical acts as monodentate ligand through the NO groups, and the Ln(III) center exhibits a dodecahedron environment. It's interesting that the mononuclear units form a pseudo-one-dimensional chain structure through intermolecular non-covalent N–O⋯O–N contacts of nitroxide groups for 1. Alternating current (ac) magnetic susceptibilities show a frequency-dependent characteristic for both 1 and 2, typical of slow relaxation of magnetization. It's the first time for a lanthanide–radical complex to form a pseudo one-dimensional structure through non-covalent O⋯O contacts.

Three new lanthanide complexes based on a nitronyl nitroxide radical [Ln(hfac)3(NIT3Ph3Py)]2 (Ln = Dy(1), Tb(2), Gd(3); hfac = hexafluoroacetylacetonate, NIT3Ph3Py = 2-(3′-(3″-pyridyl)-phenyl)-4,4,5,5- tetramethylimidazoline-1-oxyl-3-oxide) have been successfully synthesized, characterized structurally and magnetically. Single crystal X-ray diffraction analysis reveals that complexes 1–3 are isomorphous in which NIT3Ph3Py acts as a bridging ligand linking two Ln(III) ions through the nitrogen atom of pyridine ring and the oxygen atom of N O group to form a four-spin system. The magnetic studies reveal that the ferromagnetic interactions between the Ln(III) ions and nitronyl nitroxide radicals in the complexes. Moreover, alternating current (ac) magnetic susceptibilities show that Dy(III) complex exhibits frequency-dependent signals at low temperature.

In complex [Na-Dy(μ2-L)4]n(HL = 8-hydroxyquinoline) (1), the DyL4 units were linked by the NaI ions to form one-dimensional chains. The chain exhibited slow magnetic relaxation behavior at low temperature, accompanied by obvious quantum tunneling of magnetization (QTM). Very weak fluorescence was detected in 1 due to the mismatch of the state energy between DyIII and the L ligand. Through the magnetic dilution of diamagnetic YIII ions, complex [NaDy0.02Y0.98(μ2-L)4]n (2) was obtained; in 2 the QTM of DyIII was suppressed and the single ion magnet (SIM) behavior was enhanced. More interestingly, the fluorescence emission of 8-hydroxyquinoline was lightened by the YIII ions in 2, whose intensity is linearly correlated with the temperature variation. The examples of dual functional fluorescent thermometers and SIM materials are attained simply by ion dilution, achieving the effect of killing two birds with one stone.

The design on synthesizing a sturdy, low-cost, clean, and sustainable electrocatalyst, as well as achieving high performance with low overpotential and good durability toward water splitting, is fairly vital in environmental and energy-related subject. Herein, for the first time the growth of sulfur (S) defect engineered self-supporting array electrode composed of metallic Re and ReS

Multinuclear hetero-tri-spin complexes based on a methyl-pyrazole nitronyl nitroxide radical, namely, [Ln2Cu3(hfac)12(4-NIT-MePyz)4] (Ln = Gd(1), Tb(2), Dy(3); hfac = hexafluoroacetylacetone; 4-NIT-MePyz = 2-{4-(1-methyl)-pyrazolyl}-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide) have been successfully obtained through a one-pot reaction of the radical ligand (4-NIT-MePyz) with Cu(hfac)2 and Ln(hfac)3. These 2p–3d–4f complexes exhibit five-nuclear structures with the sequence [Cu–Rad–Ln–Rad–Cu–Rad–Ln–Rad–Cu], in which each 4-NIT-MePyz radical acting as a bidentate bridging ligand is coordinated to one Ln(hfac)3 unit through one oxygen atom of the NO groups and to one Cu(hfac)2 unit with one nitrogen atom from the pyrazole ring. For complex 1, based on the spin Hamiltonian calculations and MAGPACK program, it is concluded that there exist ferromagnetic couplings between GdIII and NIT radicals, as well as between CuII and free radicals with J1 = 6.8(1) and J3 = 1.3(2) cm−1, respectively, and antiferromagnetic interactions between radical and radical with J2 = −2.8(5) cm−1. Complex 2 shows frequency-dependent out-of-phase signals under a zero or 2000 Oe dc field indicating single-molecule magnetic behavior.

The combination of LnIII ions (GdIII, TbIII or DyIII) and a pyrazole nitronyl nitroxide radical results in three isomorphous complexes, namely, [Ln(hfac)3(NIT-Pyz)]2 (Ln = Gd(1), Tb(2), Dy(3); hfac = hexafluoroacetylacetone; NIT-Pyz = 2-{3-pyrazolyl}-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide). Single crystal X-ray diffraction studies revealed that all of them are composed of two crystallographically independent mononuclear systems, in which the central LnIII ions are coordinated by three hfac and one bidentate chelating NIT-Pyz radical. The central LnIII ions are all in square antiprism geometry (D4d) polyhedron configurations. Based on the spin Hamiltonian calculations, there exist antiferromagnetic couplings in the GdIII-NIT radical system in complex 1. Complexes 2 and 3 show frequency-dependent out-of-phase signals in a zero field indicating single-molecule magnetic behavior. Moreover, Tb's complex (2) shows a single thermal relaxation process with an energy barrier of 26 K. For Dy's complex (3), the Orbach and Raman processes both contribute to the magnetic relaxation behaviors.

A dynamic microporous magnet shows reversible temperature-tuned single-crystal-to-single-crystal transformations by stepwise losing of coordinated and lattice water molecules, exhibiting an unusually observed room-temperature hysteresis loop, variable magnetic ordering temperatures and high adsorption selectivity for CO2 over N2.

Prussian Blue Analogues Mn3[Fe(CN)6]2·12H2O porous nanoparticles have been achieved by coprecipitation method and using polyvinyl pyrrolidone (PVP) as a protective matrix. The obtained nanoparticles were characterized by X-ray diffraction (XRD), infrared spectroscopy (IR), X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TG), scanning electron microscopy (SEM), and high resolution transmission electron microscopy (HRTEM). The X-ray diffraction measurement results show that all the obtained nanoparticles are face centered cubic structure. The infrared spectroscopy (IR) and X-ray photoelectron spectroscopy (XPS) measurement results indicate that Mn3[Fe(CN)6]2·12H2O nanoparticles are mixed-valence, and the ratios of MnIIFeIII to MnIIIFeII in obtained nanoparticles are different in water and water-methanol mixed solvent. The magnetic studies of nanocubes (about 480 nm, coming from water synthesis) and nanospheres (about 200 nm, from co-solvent synthesis) materials show that both samples have spin-glass behavior, but magnetic property measurement results indicated Tc, Tb and Tg temperatures of Mn3[Fe(CN)6]2·12H2O decreases as the size of nanoparticle reduces.

Four unique infinite 2D Mn(II) aggregates, [Mn 3 ( μ 3 -ade) 2 (OAc) 4 X] n (X = DMF for 1 , DMA for 2 and C 2 H 5 O − for 3 ), [Mn 3 ( μ 3 -ade) 2 (ap) 2 DMF] n ( 4 ) (Hade = adenine; DMF = N , N- dimethylformamide; DMA = N , N- dimethylacetamide, OAc − = acetate ion, H 2 ap = adipic acid) with trinuclear Mn(II) as secondary building units (SBUs), have been successfully synthesized by the assembly of Hade nucleobase and manganese acetate under solvothermal conditions. The resultant complexes can be applied to explore the influence of solvent or co-ligands on the self-assembly and properties of metal complexes based on adenine. The Hade represent tridentate μ 3 -N3, N7, N9 bridging coordination modes. The acetate anions exhibit μ 2 - η 1 :η 1 bidentate, μ 2 - η 1 :η 2 tridentate mode, and μ 2 - η 0 :η 2 bidentate mode. The adipate anions in complex 4 adopt two coordination modes: one is μ 4 - η 2 :η 1 :η 1 :η 1 pentadentate mode, the other one is μ 3 - η 1 :η 2 :η 2 :η 1 hexadentate mode. Their magnetic behaviors exhibit interesting variations, in which the local net magnetization at low temperature increases from 1 to 3 . The Mn II 3 SBUs in 1 – 3 are symmetric with an inversion center, whereas that in 4 has three crystallographically independent Mn II atoms. Thus, the magnetic behaviors of 4 are different from complex 1 – 3 .

The Yinkeng orefield is located in the eastern Nanling region, South China. The Nanling region hosts numerous W(-Sn)-dominant, polymetallic deposits related to the widely distributed Mesozoic granites, making it one of the most important W-Sn polymetallic metallogenic belts in the world. In this study, we utilized multiple geophysical methods, including gravity, magnetic, audio-frequency magnetotelluric sounding (AMT), and high-resolution reflection seismic techniques, to detect the underground distribution of granites, strata, and structures. Our aims are to understand better the ore-controlling mechanisms for the large-scale W-Ag-Au-Pb-Zn aggregation, to establish a metallogenic model for this type of mineralization, and to supplement a 3000-m scientific drilling program in the Nanling region for the Chinese SinoProbe Program Project (SP-NLSD-1). In the Yinkeng orefield, an ore-controlling, NE-trending nappe structure is composed of several thrust faults at shallow depths (F1 and F2), which merge into a single major fault at depth. The Pre-Sinian sedimentary rocks of the hanging wall of these faults have much higher velocities, densities and wave impedance than the Carboniferous-Permian sedimentary rocks of the footwall. The slip surface of the nappe, which appears to have low resistivity, extends downward to a two-way travel time of more than 2.5 s, equivalent to a depth of more than 4000 m. Thrusting was from SE to NW, and the fault flattens at depth. The nappe structure may have provided channels for magmas and mineralized hydrothermal fluids. Granites in the Yinkeng area, which are spatially associated with the W-Ag-Pb-Zn orebodies, generally show high resistivity, low polarizability, low seismic velocity and medium magnetism, and their geophysical characteristics have revealed their distribution at depth. Specifically, the Gaoshanjiao granodioritic pluton, closely related to precious metal mineralization, is characterized by low density and high magnetism, allowing us to identify a large buried part of the pluton SE of the exposed body. The Jiangbei granitic pluton, which typically hosts W mineralization, has lower magnetism that reveals a NE-trending extension about 2.2–2.8 km wide at a depth of 16.6 km. One completely concealed granite, the Yinkeng pluton, lies below the nappe structure. It is geophysically similar to the Jiangbei granitic pluton but has an obviously higher magnetic signature. The high magnetism may be due to stratiform polymetallic bodies, which could represent a good exploration target for porphyry-skarn-type, W-Cu-polymetallic deposits (drilling site for SP-NLSD-1). Combined with surface mapping, the geophysical data collected in this study allow us to propose a deep exploration model that can serve as a guide for W-polymetallic ore prospecting in the Nanling and adjacent regions.

Microalgae have important applications in the aquaculture industry due to their remarkable nutritional value, especially the high contents of carotenoids. In this study, five microalgae, namely Spirulina sp., Dunaliella salina, Haematococcus pluvialis, Isochrysis galbana and Myrmecia incisa were investigated for their beneficial effects on Artemia nauplii, their predator in the food chain. For H. pluvialis (rich in astaxanthin), I. galbana (rich in fucoxanthin) and M. incisa (limited carotenoids but rich in arachidonic acid), they were cultured under either normal or stressful condition to produce the algal samples containing different amounts of carotenoids or fatty acids. Results showed that through feeding, the carotenoids in microalgae can be efficiently transferred to Artemia nauplii. In comparison with fatty acids, carotenoids made more contribution to the improved growth and health conditions of Artemia, leading to better performances in survival rate, average body length, total effective body length and total antioxidant capacity. Besides, the immunity of Artemia nauplii was also enhanced, as evidenced by the strong resistance against Vibrio parahaemolyticus-induced infection. Findings of the present study clearly supported the benefits of carotenoid-rich microalgae for Artemia nauplii, providing a feasible microalgae-based strategy to produce the nutrition-enhanced Artemia that has commercial significance.

Two water-stable silver(I) cation metal organic frameworks (MOFs), namely 2D MOF {[Ag(L)2]BF4}n (1) and 3D MOF {[Ag3(L)3]·(H2O)·(CF3SO3)3}n (2) (L = 1-(4-aminobenzyl)-1,2,4-triazole), have been prepared. 1 is the first example of a 2D MOF-based sensor for real-time discrimination of L- and D-cysteine from other amino acids through the quenching effect. Through deliberately tuning the nanoparticles of 2 under ultrasound conditions, these nanoparticles are, for the first time, successfully applied as an excellent DNA detecting platform.

• Two novel ternary Zn II -triazole-polycarboxylate framework has been synthesized and characterized.

A novel (4, 12)-connected metal-organic framework, {(NH4)2·[Co11(μ4-OH)6(CN)6(trz)12]}n, was solvothermally constructed from unusual CoII8 cubes, octahedral CoII1 subunits, and μ3-N1,N2,N4-triazolate (trz) connectors. Strong antiferromagnetic coupling between the neighboring CoII ions results in an absence of long-range magnetic ordering, leading to a strong spin-frustration with f > 62.

A field-induced MnIII-based single-ion magnet with axially elongated Jahn–Teller distortion was well isolated in a layered complex by diamagnetic NaI ions, which exhibits an effective thermal-activated energy barrier of 12.9 cm− 1 under 2.0 kOe dc field resulting from strongly axial anisotropy of the high-spin MnIII ion.

Two 4-(1H-1,2,4-triazol-1-yl)phenol (hptrz)-based transition metal complexes with different aromatic polycarboxylic acids as co-ligands, {[Cu2(H2O)4(hptrz)2(btec)]⋅2H2O}n (1) and [Cu(hptrz)2 (H2btc)2]·H2O (2) (H4btec = benzene-1,2,4,5-tetracarboxylic acid, H3btc = benzene-1,3,5-tricarboxylic acid), have been obtained, which were structurally characterized by single-crystal X-ray diffraction, elemental analysis, FT-IR spectra, thermogravimetric curves and luminescence spectra in detail. Structural analysis reveals that 1 is a 1-D infinite chain framework extended by btec4– anions, whereas 2 is isolated centrosymmetric mononuclear entities. In contrast, the neutral hptrz is a terminal ligand to complete the metal coordination sphere and it also helps to assemble the low-dimensional coordination sphere into a high-dimensional supramolecular architecture by O–H···O hydrogen-bonding interactions. Additionally, the high stability and luminescence emission suggest that 1 and 2 are good candidates for light emission materials. The magnetic features of 1 may be due to weak antiferromagnetic coupling between CuII ions which are separated by btec4– anions.

Multinuclear hetero-tri-spin complexes based on a methyl-pyrazole nitronyl nitroxide radical, namely, [Ln2Cu3(hfac)12(4-NIT-MePyz)4] (Ln = Gd(1), Tb(2), Dy(3); hfac = hexafluoroacetylacetone; 4-NIT-MePyz = 2-{4-(1-methyl)-pyrazolyl}-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide) have been successfully obtained through a one-pot reaction of the radical ligand (4-NIT-MePyz) with Cu(hfac)2 and Ln(hfac)3. These 2p-3d-4f complexes exhibit five-nuclear structures with the sequence [Cu-Rad-Ln-Rad-Cu-Rad-Ln-Rad-Cu], in which each 4-NIT-MePyz radical acting as a bidentate bridging ligand is coordinated to one Ln(hfac)3 unit through one oxygen atom of the NO groups and to one Cu(hfac)2 unit with one nitrogen atom from the pyrazole ring. For complex 1, based on the spin Hamiltonian calculations and MAGPACK program, it is concluded that there exist ferromagnetic couplings between GdIII and NIT radicals, as well as between CuII and free radicals with J1 = 6.8(1) and J3 = 1.3(2) cm-1, respectively, and antiferromagnetic interactions between radical and radical with J2 = -2.8(5) cm-1. Complex 2 shows frequency-dependent out-of-phase signals under a zero or 2000 Oe dc field indicating single-molecule magnetic behavior.

A new nitronyl nitroxide-Tb(III) complex, [Tb(hfac)3(NIT-3-Br-4Py)2] (1) (hfac = hexafluoroacetyl -acetonate, NIT-3-Br-4Py = 2-(3′-bromo-4′-pyridyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide), has been synthesized and characterized. The single-crystal X-ray diffraction analysis shows it crystallizes in monoclinic C2/c space group, and is composed of mononuclear molecules. The central Tb(III) ion is eight-coordinated by three bidentate chelating hfac anions and two monodentate NITR ligands, with a dodecahedron environment. Ac magnetic susceptibility study shows that complex 1 exhibits slow magnetic relaxation, suggesting single-molecule magnet behavior.

Two methylammonium-templated metal vanadates, namely [CH3NH3]2MV2O7 (M = Mn (1) and Cd (2)), have been solvothermally synthesized and characterized by IR, TGA, UV–Vis, single-crystal X-ray diffraction (XRD) and Powder XRD, etc. These two isostructural compounds feature an open-framework structure constructed by MO6 octahedra and V2O7 dimers. The methylammonium cations are located in the channels of the framework and act as bi-functional charge-compensating and structure-directing agents. Compound 1 exhibits an effective adsorption performance towards Eu3+ by means of ion exchange. Magnetic study reveals the antiferromagnetic exchange between Mn2+ ions in compound 1.