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Superconductivity (SC) was experimentally observed for the first time in antimony polyhydride. The diamond anvil cell combined with a laser heating system was used to synthesize the antimony polyhydride sample at high pressure and high temperature. In - situ high pressure transport measurements as a function of temperature with an applied magnetic field were performed to study the SC properties. It was found that the antimony polyhydride samples show superconducting transition with critical temperature T c 116 K at 184 GPa. The investigation of SC at magnetic field revealed the superconducting coherent length of ∼40 Å based on the Ginzburg Landau (GL) equation. Antimony polyhydride superconductor has the second highest T c in addition to sulfur hydride among the polyhydrides of elements from main groups IIIA to VIIA in the periodic table. [ABSTRACT FROM AUTHOR]

Prevention of encrustation on the surface has always been the biggest challenge for urological implants. In the field of ureteral stent design, biodegradability has attracted much attention in recent years, because biodegradable ureteral stents not only avoid secondary intervention, but also prevent encrustation due to surface renewal by degradation process. Furthermore, researches have focus on some surface parameters to provide guidance for the development of stent materials, such as hydrophilicity or surface charge. In this work, we synthesized two types of poly(ester-carbonate)s, poly(L-lactide-co-5-amino-1,3-dioxan-2-one) (P(LA-co-AC)) containing amino, and poly (L-lactide-co-5-methyl-5-carboxyl-1,3-dioxan-2-one) (P(LA-co-MCC)) containing carboxyl. Blending P(LA-co-AC) and P(LA-co-MCC) with poly(L-lactide-co-Ɛ-caprolactone) (PLACL) respectively, two types of ureteral stent materials were prepared. Due to the influence of ions formed by the dissociation of amino and carboxyl, two types of materials show differences in surface charge analyses. We further developed a dynamic urinary extracorporeal circulation (DUEC) system to assess in vitro encrustation of materials with different surface charges. The results of this comparative study identified that the materials with strong negative surface charge were most favorable for use as ureteral stent, and provided a new approach to surmount the problems faced by urological surgery which complied with the future trend of biodegradable ureteral stent design. [ABSTRACT FROM AUTHOR]

It is challenging to search for high Tc superconductivity (SC) in transition metal elements wherein d electrons are usually not favored by conventional BCS theory. Here we report experimental discovery of surprising SC up to 310 GPa with Tc above 20 K in wide pressure range from 108 GPa to 240 GPa in titanium. The maximum Tconset above 26.2 K and zero resistance Tczero of 21 K are record high values hitherto achieved among element superconductors. The Hc2(0) is estimated to be ∼32 Tesla with coherence length 32 Å. The results show strong s-d transfer and d band dominance, indicating correlation driven contributions to high Tc SC in dense titanium. This finding is in sharp contrast to the theoretical predications based on pristine electron-phonon coupling scenario. The study opens a fresh promising avenue for rational design and discovery of high Tc superconductors among simple materials via pressure tuned unconventional mechanism. Superconductivity at megabar pressures has recently attracted interest in the context of hydrides. Here, the authors demonstrate superconductivity up to 26 K at high pressure in elemental titanium, and further suggest that electron correlations contribute to the high Tc. [ABSTRACT FROM AUTHOR]

Bi2NiTiO6 compound which shows both magnetic (TM = 58 K) and ferroelectric properties (TC = 513 K) was synthesized under high pressure of 5 GPa and temperature of 1273 K. The crystal structure, as determined by X-ray powder diffraction and neutron powder diffraction, is a distorted A(B1B2)O3 type perovskite with space group Pn21a. Structural evolution of multiferroic Bi2NiTiO6 shows that there are two isostructural phase transitions at ∼2 GPa and ∼15 GPa under high pressure and at room temperature and indicates that isostructural phase transitions occurred with temperature higher than 823 K under ambient condition. All the isostructural phase transitions come from the Bi ion discontinuous shift, which identifies the phase transition at ∼15 GPa and at temperature higher than 823 K are the same. Using a modified high-T Birch-Murnaghan equation of state and a thermal-pressure approach, we have derived the thermoelastic parameters of high pressure phase Bi2NiTiO6, including the ambient bulk modulus K0, temperature derivative of bulk modulus at constant pressure, volumetric thermal expansivity, pressure derivative of thermal expansion, and temperature derivative of bulk modulus at constant volume. [ABSTRACT FROM AUTHOR]

Superconductivity (SC) was experimentally observed for the first time in antimony polyhydride. The diamond anvil cell combined with a laser heating system was used to synthesize the antimony polyhydride sample at high pressure and high temperature. In - situ high pressure transport measurements as a function of temperature with an applied magnetic field were performed to study the SC properties. It was found that the antimony polyhydride samples show superconducting transition with critical temperature T c 116 K at 184 GPa. The investigation of SC at magnetic field revealed the superconducting coherent length of ∼40 Å based on the Ginzburg Landau (GL) equation. Antimony polyhydride superconductor has the second highest T c in addition to sulfur hydride among the polyhydrides of elements from main groups IIIA to VIIA in the periodic table., (© The Author(s) 2023. Published by Oxford University Press on behalf of China Science Publishing & Media Ltd.)

Prevention of encrustation on the surface has always been the biggest challenge for urological implants. In the field of ureteral stent design, biodegradability has attracted much attention in recent years, because biodegradable ureteral stents not only avoid secondary intervention, but also prevent encrustation due to surface renewal by degradation process. Furthermore, researches have focus on some surface parameters to provide guidance for the development of stent materials, such as hydrophilicity or surface charge. In this work, we synthesized two types of poly(ester-carbonate)s, poly(L-lactide-co-5-amino-1,3-dioxan-2-one) (P(LA-co-AC)) containing amino, and poly (L-lactide-co-5-methyl-5-carboxyl-1,3-dioxan-2-one) (P(LA-co-MCC)) containing carboxyl. Blending P(LA-co-AC) and P(LA-co-MCC) with poly(L-lactide-co-Ɛ-caprolactone) (PLACL) respectively, two types of ureteral stent materials were prepared. Due to the influence of ions formed by the dissociation of amino and carboxyl, two types of materials show differences in surface charge analyses. We further developed a dynamic urinary extracorporeal circulation (DUEC) system to assess in vitro encrustation of materials with different surface charges. The results of this comparative study identified that the materials with strong negative surface charge were most favorable for use as ureteral stent, and provided a new approach to surmount the problems faced by urological surgery which complied with the future trend of biodegradable ureteral stent design.

Competing Interests: Conflict of interest The authors declare that they have no conflict of interest.

In this work, a novel compound Ba 9 V 3 Se 15 with one-dimensional (1D) spin chains was synthesized under high-pressure and high-temperature conditions. It was systematically characterized via structural, magnetic, thermodynamic and transport measurements. Ba 9 V 3 Se 15 crystallizes into a hexagonal structure with a space group of P-6c2 (188) and the lattice constants of a  =  b  =  9.5745(7) Å and c  =  18.7814(4) Å. The crystal structure consists of face-sharing octahedral VSe 6 chains along c axis, which are trimeric and arranged in a triangular lattice in ab-plane. Ba 9 V 3 Se 15 is a semiconductor and undergoes complex magnetic transitions. In the zero-field-cooled (ZFC) process with magnetic field of 10 Oe, Ba 9 V 3 Se 15 sequentially undergoes ferrimagnetic and spin cluster glass transition at 2.5 K and 3.3 K, respectively. When the magnetic field exceeds 50 Oe, only the ferrimagnetic transition can be observed. Above the transition temperature, the specific heat contains a significant magnetic contribution that is proportional to T 1/2 . The calculation suggests that the nearest neighbor (NN) intra-chain antiferromagnetic exchange J 1 is much larger than the next nearest neighbor (NNN) intra-chain ferromagnetic exchange J 2 . Therefore, Ba 9 V 3 Se 15 can be regarded as an effective ferromagnetic chains with effective spin-1/2 by the formation of the V(2) (↓) V(1) (↑) V(2) (↓) cluster.