[en] Ordered porous polymer (OPP) materials have extensively application prospects in the field of separation and purification, biomembrane, solid supports for sensors catalysts, scaffolds for tissue engineering, photonic band gap materials owing to ordered pore arrays, uniform and tunable pore size, high specific surface area, great adsorption capacity, and light weight. The present paper reviewed the preparation techniques of OPP materials like breath figures, hard template, and soft template. Finally, the applications of OPP materials in the field of separation, sensors, and biomedicine are introduced, respectively. - Highlights: • Breath figures involve polymer casting under moist ambience. • Hard template employs monodisperse colloidal spheres as a template. • Soft template utilizes the etched block in copolymers as template

[en] Underground borehole drilling usually causes instability in the surrounding coal due to in situ stress redistribution (including stress concentration and stress release). However, the mechanisms of unloading-induced coal strength reduction are still poorly understood. The primary objective of this study is to investigate the effect of confining pressure unloading on soft coal strength reduction for borehole stability analysis. A series of mechanical tests were conducted on both the traditionally and newly reconstituted coal samples under two different experimental stress paths, including conventional uniaxial/triaxial compression and triaxial compression with confining pressure unloading. The unloading stress path was obtained by analyzing the stress redistribution around a borehole, to capture a more accurate coal mechanical response. According to our experimental results, plastic deformation generated before failure under the unloading stress path is smaller than that generated under the conventional loading stress path. Furthermore, the cohesion of the traditionally and newly reconstituted samples diminishes approximately by 44.77 and 29.66%, respectively, with confining pressure unloading, indicating that there is a significant reduction in coal strength due to confining pressure unloading. The mechanism for unloading-induced coal strength reduction comes from confining pressure unloading-induced increase in shear stress on the fracture surface and a decrease in shear strength. This effect increases the shear slipping potential, whose driving force generates tension fractures at both ends of the preexisting fractures.

[en] Objective: To explore the correlation between thyroxine hormone and the severity of coronary artery disease (CAD). Methods: 158 patients with coronary adisease were entered consecutively into the study. They were separated into control group (absence of CAD, n = 98) and CAD group (presence of CAD, n = 60). Based on the number of vessel disease, CAD group was further divided into three sub-groups: single-vessel CAD subgroup (n = 30), bi-vessel CAD subgroup (n = 15) and multi-vessel CAD subgroup (n = 15). Serum free triiodothyronine (fT₃), free thyroxine (fT₄), thyroid stimulating hormone (TSH) were tested by electro chemiluminescence; high density lipoprotein cholesterol (HDL-C) and total cholesterol (TC) were measured by cholesterol oxidase method; and Gensini scoring system was used to evaluate the degree of coronary artery stenosis. Results: The levels of fT₃ in both bi-vessel CAD and multi-vessel subgroups were higher than those in control group (t = 1.947, 6.415, both P < 0.05). And the level of fT₄ in multi-vessel subgroup was also higher than that in control group (t = 3.026, P < 0.05). fT₃ was an independent risk factor of CAD using Logistic regression model. In addition, fT₃ was negatively correlated with Gensini scoring inmultiple linear regressions. Gensini scores would increase by 1 as long as the level oft fT₃ decreases 0.234 pmol/L. Conclusions: fT₃ level decreased in patients with CAD, and correlated with the severity of CAD. Gensiniscores would increase 1 as long as fT₃ decreases 0.234 pmol/L, which could be supposed as a sensitive predictor of CAD.(authors)

[en] Highlights: • The sensory neuropeptides of CGRP and SP significantly increased after renal IR injury in kidney. • The large dose of capsaicin treatment in neonatal rats resulted in degeneration of capsaicin sensitive sensory nerves. • The degeneration of capsaicin sensitive sensory nerves and the reduction of CGRP and SP aggravated IR-induced AKI in rats. • The degeneration of capsaicin sensitive sensory nerves activated the ERK signal pathway of spinal cord and kidney. Acute kidney injury (AKI) is a common kidney disorder which is associated with a high risk of mortality. Extensive evidence revealed the participation of renal afferent sensory nerves in the pathophysiology of renal ischemia reperfusion (IR) injury, however the role of these nerves in renal IR injury is controversial and remains to be further explored. Here, we report that capsaicin sensitive sensory nerves and neuropeptides prevented renal damage in AKI induced by IR injury. The sensory afferent degeneration model was established by injecting 50 mg/kg of capsaicin to male neonatal rats and verified by the tail flick test and reduced sensory neuropeptide of substance P and calcitonin gene related peptide in spinal cord, dorsal root ganglion and kidney after 12 weeks. Then, a model of renal IR injury was established. The sensory afferent degeneration in the AKI group increased the level of serum creatinine, NGAL and KIM-1, aggravated to some extent renal pathological damage, and enhanced the proinflammatory cytokines expressions and tubular cell apoptosis. In addition, it was also discovered that the level of phospho-ERK/ERK (p-ERK/ERK) showed an increase in spinal cord and kidney after degeneration of capsaicin sensitive sensory nerves. In conclusion, the degeneration of sensory nerves aggravated IR-induced AKI in rats, and the activated ERK signaling in spinal cord and kidney after sensory afferent degeneration might be the possible mechanism in the aggravated renal injury.

[en] Titanium isopropoxide, ammonium carbonate and nickelous nitrate were used as the sources of titanium, nitrogen, and nickel to prepare titania photocatalyst co-doped with nitrogen and nickel by means of the modified sol-gel method. The photocatalyst was characterized by X-ray diffraction (XRD), UV-vis diffusive reflectance spectroscopy (DRS), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM). The prepared N-Ni co-doped photocatalyst showed optical absorption in the visible light area and exhibited excellent photocatalytic ability for the degradation of formaldehyde under visible light irradiation. The effects of annealing temperature and component on the phase composition and photocatalytic activity were investigated. The results demonstrated that nitrogen atoms was weaved into the structure of titania and led to the response to visible light. However, nickel atoms existed in the form of Ni₂O₃, dispersed on the surface of TiO₂, suppressed the recombination of photo-induced electron-hole pairs, raised the photo quantum efficiency, and led to the enhancement of photocatalytic performance. The increase of photoactivity was attributed to the synergistic effects of co-doping

[en] The influences of doping on electronic structures and mechanical properties of BaHfO₃ are investigated by using first-principles plane-wave density functional theory within the generalized gradient approximation (GGA). The electronic structure calculations show that the lattice constant of optimized BaHfO₃ agrees with the experimental value, and BaHfO₃ and doped BaHfO₃ with Sr or Ti are both indirect band gap materials. Specifically, the band gap of Ba_0.5 Sr_0.5 HfO₃ increases and the characteristics of insulator enhances, while the band gap of BaHf_0.5 Ti_0.5O₃ is obviously reduced and the features of semi conductor material are displayed. The analysis of the density of states shows that the change of the band gap after doping is due mainly to the movement of the bottom of conduction band. The analysis of mechanical properties indicates that the shear modulus and Young's modulus of Ba_0.5 Sr_0.5 HfO₃ decrease comparing with BaHfO₃, which leads to the decrease of the hardness of the material. But for BaHf_0.5 Ti_0.5O₃, both the shear modulus and Young's modulus increase, which causes the enhance of hardness. Electron density distribution analysis reveals that the doping changes the valence electron concentration distribution of the system, resulting in the change of bonding characteristics of BaHfO₃, and this is the underlying reason for the change of hardness of the material. Thus, the doping can effectively control the hardness of the system. The results of the study provide a theoretical basis for the design and application of doping BaHfO₃ electromechanical materials. (authors)

[en] The evaluation of the influence of the bending deformation of silicon nanobridges on their electrical properties is crucial for sensing and actuating applications. A combined theory/experimental approach for determining the resistivity and the density of interface states of the bending silicon nanobridges is presented. The suspended p-type silicon nanobridge test structures were fabricated from silicon-on-insulator wafers by using a standard CMOS lithography and anisotropic wet etching release process. After that, we measured the resistance of a set of silicon nanobridges versus their length and width under different bias voltages. In conjunction with a theoretical model, we have finally extracted both the interface state density of and resistivity suspended silicon nanobridges under different bending deformations, and found that the resistivity of silicon nanobridges without bending was 9.45 mΩ·cm and the corresponding interface charge density was around 1.7445 × 10¹³ cm⁻². The bending deformation due to the bias voltage slightly changed the resistivity of the silicon nanobridge, however, it significantly changed the distribution of interface state charges, which strongly depends on the intensity of the stress induced by bending deformation. (semiconductor physics)

[en] A numerical method based on smoothed particle hydrodynamics with adaptive spatial resolution (SPH-ASR) was developed for simulating free surface flows. This method can reduce the computational demands while maintaining the numerical accuracy. In this method, the spatial resolution changes adaptively according to the distance to the free surface by numerical particle splitting and merging. The particles are split for refinement when they are near the free surface, while they are merged for coarsening when they are away from the free surface. A search algorithm was implemented for identifying the particles at the free surface. A particle shifting technique, considering variable smoothing length, was introduced to improve the particle distribution. The presented SPH-ASR method was validated by simulating various free surface flows, and the results were compared to those obtained using SPH with uniform spatial resolution (USR) and experimental data.

[en] Spiropyran-modified silicon quantum dots (Si QDs) were successfully fabricated through covalently linking the aminated Si QDs and spiropyrans. In comparison with Si QDs, the fluorescence emission peaks of the Si QDs in the spiropyran-modified Si QDs always locate at 525 nm irrespective of the excitation wavelengths. The spiropyran-modified Si QDs showed reversible photoluminescence. Blue-green fluorescence of the spiropyran-modified Si QDs could be gradually switched off, and red fluorescence could be gradually switched on with UV irradiation. The process could be reversible with visible light irradiation. The reversibly switchable photoluminescence of the spiropyran-modified Si QDs using UV and visible light irradiation could also be multiply repeated with good stability. Therefore, the spiropyran-modified Si QDs could be a promising candidate in many potential application areas such as photo-switch, data storage, and biolabeling and bioimaging.

[en] Flexible and wearable electrical devices have attracted extensive research attention in recent years. In the device fabrication process, the low-cost and compatibility with industrialized mass production are of great importance. Herein, membrane-based flexible photodetectors (PDs) based on Polyvinylidene Fluoride filter membrane with the structure of Ag nanowires (NWs)/ZnO NWs/graphene were fabricated by a full-solution method. The built-in electric field due to the ZnO/graphene Schottky junction is in favor of the separation and transport of photo-generated carriers, leading to enhanced device performance. The I _light/I _dark ratio was as high as ∼10², which is far superior to that of the reported ZnO-based fiber-shaped PDs. The PDs with remarkable flexibility can be easily attached to the human body and even can work steadily under serious bending conditions. Particularly, the photocurrent can keep 95% of the maximum value after the PD was bent 1000 times. In addition to the wearable applications, the membrane-based PD arrays can also be applied for imaging application. (paper)