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Major symptoms of depression are commonly observed in patients requiring total hip arthroplasty (THA), and this is associated with increased pain scores and opioid consumption. We aimed to investigate the analgesic effect of duloxetine in these high-risk patients.Among 263 patients scheduled for primary unilateral THA, 67 patients who scored at least 8 on the 17-item Hamilton Depression Scale (HAMD) were enrolled in this study. Patients were randomized to the duloxetine group (60 mg daily, from the day of surgery to postoperative day 6) or the placebo group. The postoperative visual analog scale (VAS) score during walking, the VAS score during hip flexion, and resting VAS score was measured. Postoperative morphine consumption, hip range of motion (ROM), Harris hip score (HHS), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) function, postoperative length of stay (LOS), and adverse events were recorded.The duloxetine group had significantly lower VAS scores during walking and hip flexion from postoperative day 3 to week 3 than the placebo group. With regard to the resting VAS score, duloxetine showed a better analgesic effect from postoperative day 3 to week 2 than placebo. Patients in the duloxetine group had less consumption of morphine. The duloxetine group exhibited better hip function scores, including ROM, HHS, and WOMAC function scores than the placebo group. No significant difference was observed in LOS or adverse events between groups.Perioperative short-term duloxetine provides advantages in decreasing pain, reducing morphine consumption, and increasing hip function in THA patients who have depressive symptoms.

Nicotinamide adenine dinucleotide (NAD+) is involved in regulating oxidative stress. Although NAD+ is associated with various health issues, its role in the intestinal microcirculation in necrotizing enterocolitis (NEC) remains to be confirmed. In the current study, we explored whether nicotinamide riboside (NR), a natural NAD + precursor, ameliorates the severity of NEC through endothelial nitric oxide synthase(eNOS) signaling.A mouse experimental NEC model was induced by formula gavage and hypoxia in full-term mouse pups. Intestinal endothelial cells (MIMECs) were isolated and subjected to stress using tumor necrosis factor (TNF)-α. NR was administered to assess the intestinal microcirculation and lipid peroxidation levels and to explore the involved signaling pathways.NAD + levels were reduced after induction of NEC stress, which was associated with intestinal injury. NR administration promoted NAD + levels, attenuated oxidative stress and relieved the symptoms of experimental NEC, which were relevant to increased intestinal microcirculatory perfusion through the sirtuin (SIRT) 1 pathway in experimental NEC mice. However, this improvement was not found in eNOS-knockout mice. Consistently, MIMECs exposed to TNFα showed decreased SIRT1 activity associated with increased eNOS acetylation, which could bring about endothelial dysfunction due to limited nitric oxide production. NR administration increased the NAD + content and repressed the production of reactive oxygen species (ROS) in MIMECs under TNFα stress. NR also promoted SIRT1 activity and accordingly suppressed the eNOS acetylation levels under TNFα stress.The current data indicate that NR administration improves the survival of experimental NEC mice via SIRT1-associated eNOS acetylation/deacetylation modulation, which is implicated in endothelial dysfunction. Although NR is commonly found in the human diet, it may also be a promising strategy for NEC treatment because of its pathogenic association with NEC.

The exploration towards cost-effective filler metal for ceramics joining has always been the key issues for ceramics joining. Herein, we reveal that the Al metal prefers to spread on the ZrO2 based ceramic under the air heating condition, due to the geometric limit effects by in-situ formed dense Al2O3 surface. Inspired by this, the joining of ZrO2 based ceramics was realized in air with Al metal as filler, through the diffusion of Al towards ceramic side. The Al element can induce obvious interfacial bonding effect on Al2O3 layer and ZrO2 ceramic, where the hybridization among the Al-p, Zr-d and O-p orbitals plays a key role. The in-situ formed Al2O3 layer on Al filler surface is vital for forming the fine interface (shear strength of ∼36 MPa), which results in the relief of lattice mismatch and peak stress at ceramic-filler metal transition interface.

Nowadays, SiO2 based material is one of the widest used materials in optical, microelectromechanical system, aerospace and some other industries. In practical application, SiO2 based materials are required to be joined with themselves or other heterogeneous materials to assemble products with various functions. And the joining quality directly affects the mechanical performances and functional properties of assembled products. Though many researchers studied different joining technologies, explored the microstructure of joining interface and tested after-joining properties, a review that summarizes the recent cutting-edge researches and development tendency of joining technologies for SiO2 based ceramics is still absent. Therefore, according to different applications and requirements, this review summarizes the widely used joining technologies and discusses corresponding joining mechanisms, current research progress and suitable applications. Due to the wide applications in specific industry, laser welding, anodic bonding and wafer bonding are discussed in detail. Further, brazing, the widest used method in SiO2 joining, has been elaborated deeply in its wetting mechanism, residual stress control, interfacial microstructure and mechanical performance aspects. In the end, this review proposed the future development trends of SiO2 ceramics joining, aiming at offering a full-view of potential improvements in SiO2 ceramic joining technologies.

AgCuTi-based composite fillers reinforced with Carbon Nanotubes (CNTs) were prepared by mechanical ball milling and ultrasonic agitation. The morphological features, chemical components, and melting characteristics of the composite fillers with different content of CNTs addition were investigated using Field Emission Scanning Electron Microscopy (FESEM), X-Ray Diffraction (XRD) and a Differential Scanning Calorimeter (DSC). After being heated at 900 ℃, the microstructure of the composite fillers was examined through FESEM and Transmission Electron Microscopy (TEM) to analyze the interfacial characteristics in the AgCuTi-CNTs system. The microstructures of the composite fillers with 0.5wt% CNTs and 0.1wt% CNTs were comparedwt%. It was found that 0.5wt% CNTs were favorable for dispersive distribution of the structure. Nano-sized TiC particles formed in the reaction of CNTs with Ti, resulting in the transformation of TiCu2 with high Ti content and Ti2Cu3 phases to TiCu4 phase with low Ti content. Additionally, the microstructure evolution of the composite fillers was studied by changing the ratio of Ti/CNTs. Results showed that CNTs significantly influenced the wettability of the AgCuTi filler. After addition of 0.3wt% of CNTs, the spreading area of the composite filler on the C/C composite increased by 145.9%.

Surface structure of C/C composites has been regulated through electrochemical corrosion at room temperature to modify the residual stress and improve the joining strength when brazed to Nb. The unique crevice corrosion in C/C composites is investigated to reveal the change of corrosion depth and fiber size. The interlacing zone of carbon fiber reinforced brazing alloy replaces the reaction layer in the original joint. Joining area is increased dramatically and the continuous crack will be hindered. The interlacing zone eliminates the stress concentration and relieves the residual stress through reducing the property mismatch. All advantages contribute to the joining quality of C/C Nb. Shear strength of C/C Nb joint with 80 μm depth reached 37.7 MPa, which was 1.2 times higher than that of original joint. Surface structure design of C/C composites not only expands the application in structure component, but also exhibits the promising application in energy field.

Joining of ceramic and metal is a key component in microelectronic device manufacturing, in which the integrity of bonded interface is critical in the performance and stability of the devices. Current methods with a problem of thick transition layer at the interface impeded heat flow, which degraded device service life seriously. Herein, we propose a laser-assisted bonding approach to join ceramic to metal directly without any intermediate material. By focusing the laser on the surface of β-Si3N4 ceramic, the Si microcrystalline layer with stacked α-Si3N4 nanocrystals was prepared first. The face-centered cubic (fcc) Si and hexagonal close-packed (hcp) β-Si3N4 substrate take the coherent orientation relations of [001]fcc║[0001]hcp and (220)fcc║( 10 1 ¯ 0 )hcp. Then, the defect-free Si3N4/Cu bonded interface obtained by the reaction of the formed Si and Cu at elevated temperature in the 805 - 900°C range for 30 min demonstrated a strong and stable joining of ceramic to metal. The introduction of the laser provides a novel approach to join ceramics to metals, and the ceramic/metal component is expected to be a new configuration for package substrate in high-power device applications.

To extend the application of the SiO2f/SiO2 composites, self-joining process is indispensable. Reliable self-joining of SiO2f/SiO2 composites was achieved by Bi2O3–B2O3–ZnO glass. With a low glass transition temperature, the onset temperature of residual stress is much lower than that of active brazing. In addition, bismuth glass exhibits a good wettability on the surface of SiO2f/SiO2 composites. When the joints were brazed at 750 °C/30 min, the average shear strength of the joints reached 21.2 MPa, reaching 77.8% of the shear strength of SiO2f/SiO2 composites. This technology can effectively fill the bank of self-joining of SiO2f/SiO2 composites.

The effect of Carbon Nanotubes (CNTs) content on the wettability of AgCu-4.5Ti + x CNTs (wt%) composite filler alloys on C/C composite was investigated. The results show that the added CNTs reacted with element Ti in the filler and produced the dispersed fine in situ synthesized TiC particles, which increased the consumption of element Ti and provided the nucleus for the growth of Ti-Cu compounds simultaneously. The above effects of introducing CNTs, inhibited the formation of Ti-Cu compounds, also changed the distribution of compounds, which dramatically influenced the interfacial microstructure and characteristics of wetting behavior. The increase of CNTs content refined and dispersed coarse Ti-Cu compounds, decreased the initial spreading temperature, and improved the wettability, but high content of CNTs (more than 0.3wt%) decreased the wettability of the filler alloy. The wetting interfacial microstructure of corresponding composite filler alloys were analyzed by Scanning Electron Microscope (SEM), Energy Dispersive X-ray Spectrometer (EDS) and Transmission Electron Microscope (TEM), which consisted of TiC, TiCu, TiCu2 and TiCu4 compound. The typical wetting behavior of AgCu-4.5Ti + 0.3wt% CNTs composite filler on C/C composite was divided into four stages. The effect mechanism of CNTs content on the wetting behavior was proposed.

Background H2O2, as a green and environmentally friendly oxidant, has been widely used in our daily life and industrial production. It is of epoch-making significance to develop highly efficient photocatalysts for producing H2O2. In recent years, g-C3N4 has received much attention due to its high chemical stability, environmental friendliness and suitable energy band structure. However, some shortcomings including the fast recombination of photogenerated electron-hole pairs and small specific surface area in traditional 2D g-C3N4 seriously impede its photocatalytic performance for the production of H2O2. Methods 1D hollow nanostructures possess intriguing physicochemical properties and are adopted to overcome the intrinsic shortcomings of g-C3N4. Herein, g-C3N4 with a hollow hexagonal prism structure (CN HP) is prepared to produce H2O2. It is characterized by XRD, XPS, SEM, HRTEM, ESR and DRS. BET, PL spectra, photocurrent and EIS are used to explain the enhanced photocatalytic performance. Significant findings Compared with traditional 2D g-C3N4, the specific surface area of CN HP increases to 41.513 m2/g, providing more active sites. Meanwhile, its hollow tubular structure can enhance the migration of photogenerated electrons to the catalyst surface, and electrons with a longer lifetime can participate in photocatalytic reactions to achieve high efficiency. The yield of H2O2 production can up to 4.08 μmol over CN HP in 40 min, which is about 7 times higher than that of traditional 2D g-C3N4, and the apparent quantum efficiency (AQE) of H2O2 production at 420 nm is 2.41%. This research provides a valuable reference for the development of green materials for efficient photocatalytic production of H2O2.

Based on reactive air brazing (RAB), we designed a new type of sealant (Ag–xCuAlO2) for joining 3 mol.% yttria-stabilized zirconia (YSZ) ceramics and AISI 310S stainless steel. The CuAlO2 content affected the wettability of the sealant on the YSZ surface, and the joints had a high shear strength when Ag–2 wt.%CuAlO2, which had a small contact angle on the YSZ substrate, was used as the sealant. In addition, the thickness of the oxide layer was reduced compared to that for the Ag–CuO sealant. The effects of the processing parameters on the microstructure and shear strength of the joints were investigated, and the as-brazed joints reached their highest shear strength (93.7 MPa) when brazed at 1040 °C for 30 min. After high-temperature oxidation at 800 °C for 200 h, the shear strength of the joints remained at 50 MPa, and no apparent change in the microstructure was observed, proving that the joints possessed excellent oxidation resistance.

Due to the formation of excessive brittle compounds, the joint of Cf/C composites and single crystal Ni-based superalloy (DD3) has relatively low mechanical properties, greatly degrading the reliability of joints. In this work, an active Cu interlayer is introduced to adjust the interfacial reaction and microstructure of the joint. Effects of the Cu interlayer on the interfacial reaction and microstructure of joints are investigated in detail. Especially, the effect of the Cu interlayer on the joining stability of the joint is first analyzed, and its enhancement mechanism is further clarified. Adding an active Cu interlayer prevents the intense diffusion of Ni and Al from the DD3 side to the Cf/C side by a reactive adjusting process. Therefore, brittle AlNi2Ti phases only can be formed in the region nearby the DD3. Besides, the content of the Cu solid solution in the brazed seam is increased, significantly improving the plastic deformation ability of the joint. The maximum shear strength of Cf/C-DD3 joints with the Cu interlayer reaches to 54 MPa, approximately 50% higher than that of the joint without the Cu interlayer. Furthermore, a stable joint strength is obtained in a broader brazing temperature range from 880 °C to 940 °C.