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We report on the synthesis of two acentric and one centrosymmetric Zn metal–organic complexes with 3-tetrazolemethyl pyridine spacers obtained in situ by hydrothermal routes. X-ray diffraction structural analysis reveals that they have the same equivalent nodes but with dissimilar topologies. The two acentric frameworks [Zn(Tzmp)Cl]n (1) and ([Zn(Tzmp)Br]n (2), HTzmp = 3-tetrazolemethyl pyridine) are isomorphism which exhibit an acentric 3D framework with (10, 3)-b net called “ths”, while the centrosymmetric complex ([Zn(Tzmp)N3]n (3)) features a distinctive 2D sheet with Shubnikov hexagonal plane net. Photo-luminescent studies suggest the ligand-field strength of coordinated negative ions (Cl− > Br− > N3−) has ordered adjusting effects on the emission redshift. The second harmonic generation (SHG) measurement shows that compounds 1 and 2 are nonlinear optically active, with SHG responses being 2/3 and half of the standard potassium dihydrogen phosphate (KDP), respectively.

Reversible crystal state structural phase transitions molecular materials without metal have been received increasing interest recently. Here we successfully synthesized a novel ternary neutral co-crystallized organic adduct hexamethylenetetramine·1-adamantane carboxylic acid·chloroform, 1, which accompanies with an interesting reversible phase transition close to the zero temperature (263 K). We confirmed this reversible phase transition by its switchable thermal dielectric behaviors and unit cell constants anomalies around the phase transition temperature (Tc). X-ray single crystal diffraction analysis above (1-RTP) and below (1-LTP) Tc suggests that the order-disorder motion from the adamantane ring in 1-adamantane carboxylic acid triggered the reversible phase transition.

Dielectric relaxations have widely applied on high permittivity capacitors, dielectric switches, ferroelectrics, pyroelectrics, and electrical insulating materials. However, few investigations of large dielectric relaxation behaviors on organic–inorganic hybrid materials have been documented before. Here we present a novel two-dimensional succinimide lithium(I) hybrid compound, [Li(PDD)2ClO4]n, 1, (PDD = 2,5-pyrrolidinedione = succinimide) which shows reversible phase transition behavior in the vicinity of 228 K accompanied by an unusual symmetry breaking from I41/amd to C2/c. X-ray single crystal diffractions analysis indicates the twist motion of pyrrolidine heterocycles, and order–disorder motion of ClO4– anions triggered the reversible phase transition. By means of an intuitive crystallographic model (rattling ion model), we further illustrated the mechanism of the interesting reversible phase transition. Particularly, 1 shows ultralarge dielectric relaxation behavior in the vicinity of the phase tran...

Solid-to solid-state reversible phase transitions are widely used in switchable dielectrics, ferroelectrics, piezoelectrics, and pyroelectric and non-linear optical materials. Herein we report a new crown ether clathrate, [Habf-(18-crown-6)1.5]+ [PF6]- (Habf = p-ammonium benzene formamide) which shows an interesting reversible phase transition near room temperature (263 K). X-ray single crystal diffraction analysis shows that the synergetic rotation motion between the 18-crown-6 crown ethers and the order-disorder motions of both hexafluorophosphate guest anions and 18-crown-6 crown ether host molecules lead to the phase transition. This reversible phase transition is confirmed by an evident thermal anomaly behavior around 263 K. The apparent step-like dielectric change around the phase transition indicates that it has potential application in dielectric switches.

Molecular ferroelectrics have displayed a promising future since they are light-weight, flexible, environmentally friendly and easily synthesized, compared to traditional inorganic ferroelectrics. However, how to precisely design a molecular ferroelectric from a non-ferroelectric phase transition molecular system is still a great challenge. Here we designed and constructed a molecular ferroelectric by double regulation of the anion and cation in a simple crown ether clathrate, 4, [K(18-crown-6)]+ [PF6 ]- . By replacing K+ and PF6- with H3 O+ and [FeCl4 ]- respectively, we obtained a new molecular ferroelectric [H3 O(18-crown-6)]+ [FeCl4 ]- , 1. Compound 1 undergoes a para-ferroelectric phase transition near 350 K with symmetry change from P21/n to the Pmc21 space group. X-ray single-crystal diffraction analysis suggests that the phase transition was mainly triggered by the displacement motion of H3 O+ and [FeCl4 ]- ions and twist motion of 18-crown-6 molecule. Strikingly, compound 1 shows high a Curie temperature (350 K), ultra-strong second harmonic generation signals (nearly 8 times of KDP), remarkable dielectric switching effect and large spontaneous polarization. We believe that this research will pave the way to design and build high-quality molecular ferroelectrics as well as their application in smart materials.

Objective This study was designed to investigate the effects of curcumin on inflammatory factors and ECM expression in exercise-induced renal ischemia reperfusion injury in rats. Methods Sixty 7-week-old male SD rats were divided randomly into three groups: group A (normal control group, n=12), group B (overtraining group, n=24) and group C (curcumin + overtraining group, n=24). Group B and C performed 6 weeks of incremental load training on the treadmill. 24 hours after the last training, the rats were anesthetized intraperitoneally, the morphology of renal tissue and the deposition of glomerular ECM were observed using light microscope，the related biochemical indexes were tested. Results (1) the renal structure of rats in group A were normal, histopathological changes were observed in group B and C, Paller score of group B were significantly higher than group A(P

Objective Long-term intensive training may led to ischemia oxygen reaction and increase the ROS. Astaxanthin, as the super antioxidant, was investigated to against anti-oxidative stress. By supplementing the astaxanthin, we wanted to observe if it can mediated Nrf2 reduces myocardial cell oxidative injury in rats after high intensity training of 6 weeks. Methods 7-week SD male rats were divided into 3 groups randomly: control group ( C group，n =10)，high intensity training group ( HT group，n = 15)，astaxanthin and high intensity training group (HTA group，n = 15) . The rats in HTA group were given with astaxanthin 20 mg /kg·d and in HT group were given with oil during the training day．The serum cTnI，myocardial apoptosis index, the expression of myocardial BAX, Bcl2, Nrf2, HO-1, myocardial MDA，SOD and T- AOC activity were measured 24 hours after the last training． Results After 6-week tranning of high intensity, compared with group C, the serum cTNI, myocardial apoptosis index, the expression of BAX and myocardial MDA were significantly higher in group HT(P

The effect of applied forging pressure on microstructure and mechanical properties of 6061 aluminum alloy was examined. The results showed that the ultimate tensile strength, elongation and hardness of the alloy after heat-treated treatment increase with the applied forging pressure, and the corresponding highest values, 365MPa, 11.52% and 146.53HV, were obtained at the applied forging pressure of 120MPa. Compared to casting condition without forging pressure, the ultimate tensile strength, elongation and hardness can be increased by 22.8%, 98.2% and 48.7%, respectively. The defects such as the shrinkage pores and cracks were absent in the microstructure due to the applied forging pressure. The SEM observation indicated that the fracture mode of 6061 aluminum alloy is more ductile at higher applied forging pressure.

For the purpose of investigations of the different situations when the cells of Acidianus manzaensis can or can not attach the surface of the chalcopyrite. Three experiments were carried out in the modified shake flasks, and in one of the experiments the cells could not attach the surface of the chalcopyrite, but could participate in the solution chemistry of the process. The redox potential, pH, cell density, copper, ion and thiosulfate concentration in the solution were monitored in the experiments, and the morphological feature and chemical composition of the leached residues were analyzed by SEM and XRD. The most leach effiency of Cu and Fe was reached in the experiment that the Acidianus manzaensis could attach the surface of the chalcopyrite. However, the unattached Acidianus manzaensis could also leach the chalcopyrite, but it was less actively than attached cells. There was no precipitation of jarosite in the leached residues of the three experiments, but there was sulfur in the leached residues when the cells could not attach the chalcopyrite. So the surface passivating layer of sulfur can be removed only when the Acidianus manzaensis can attach the surface of the chalcopyrite. From these results it become apparent that the leach of the chalcopyrite is the cooperative action of the attached and unattached Acidianus manzaensis.

We experimentally investigate the quantum-correlated twin beams generated through stimulated nondegenerate four-wave mixing in the double-lambda atomic system. A 2.5-dB noise reduction of intensity difference with 18.4-GHz frequency difference at the cesium D1 line is observed in a Cs vapor cell. The quantitative theoretical analysis reveals the experimental difficulty in getting high quantum correlation in Cs atoms because of the large hyperfine splitting of the ground states. However, it is favorable for obtaining quantum correlation in a wide range of pump detunings and relative long lengths of vapor cells. This quantum correlation provides a potential resource for possible coherent interfaces between atomic and solid-state systems due to its wavelength at the Cs D1 line which lies well within the wavelength regime of the exciton emission from InAs quantum dots.

Three different methods are used to manipulate and control phthalocyanine based single molecular rotors on Au (111) surface: (1) changing the molecular structure to alter the rotation potential; (2) using the tunnelling current of the scanning tunnelling microscope (STM) to change the thermal equilibrium of the molecular rotor; (3) artificial manipulation of the molecular rotor to switch the rotation on or off by an STM tip. Furthermore, a molecular 'gear wheel' is successfully achieved with two neighbouring molecules.