特种工程胎硫化外胎质量缺陷原因分析以及解决措施

我公司使用的硫化机采用氮气定型,二次水硫化的工艺。由于特种工程胎胎体偏厚且大,成型机都比较大,生产过程中的帘布筒、钢丝、胎侧等部件都比较重且大。成型胎面使用胎面缠绕机缠绕,所以整个生产过程难度较大。特种工程胎硫化外胎的主要质量问题有:胎面皮泡、胎侧缺胶、胎侧泡、胎肩侧皮泡、子口内侧露线、子口缺胶、胎肚内缺(窝气)、胎肚露线、胎肚皮泡、胎肚串泡、子口支边、胎冠支边、子口鼓包、外胎花缺等。通过对特种工程胎硫化外胎质量缺陷原因分析,找到相应的解决措施,从而减少硫化外胎质量缺陷。     

Current advances concerning the most cited metal ions doped bioceramics and silicate-based bioactive glasses for bone tissue engineering

Studies related to biomaterials that stimulate the repair of living tissue have increased considerably, improving the quality of many people's lives that require surgery due to traumatic accidents, bone diseases, bone defects, and reconstructions. Among these biomaterials, bioceramics and bioactive glasses (BGs) have proved to be suitable for coating materials, cement, scaffolds, and nanoparticles, once they present good biocompatibility and degradability, able to generate osteoconduction on the surrounding tissue. However, the role of biomaterials in hard tissue engineering is not restricted to a structural replacement or for guiding tissue regeneration. Nowadays, it is expected that biomaterials develop a multifunctional role when implanted, orchestrating the process of tissue regeneration and providing to the body the capacity to heal itself. In this way, the incorporation of specific metal ions in bioceramics and BGs structure, including magnesium, silver, strontium, lithium, copper, iron, zinc, cobalt, and manganese are currently receiving enhanced interest as biomaterials for biomedical applications. When an ion is incorporated into the bioceramic structure, a new category of material is created, which has several unique properties that overcome the disadvantages of primitive material and favors its use in different biomedical applications. The doping can enhance handling properties, angiogenic and osteogenic performance, and antimicrobial activity. Therefore, this review aims to summarize the effect of selected metal ion dopants into bioceramics and silicate-based BGs in bone tissue engineering. Furthermore, new applications for doped bioceramics and BGs are highlighted, including cancer treatment and drug delivery.     

Metal chlorides-promoted ammonia absorption of deep eutectic solvent

Ammonia is considered as a promising hydrogen or energy carrier. Ammonia absorption or adsorption is an important aspect for both ammonia removal, storage and separation applications. To these ends, a wide range of solid and liquid sorbents have been investigated. Among these, the deep eutectic solvent (DES) is emerging as a promising class of ammonia absorbers. Herein, we report a novel type of DES, i.e., metal-containing DESs for ammonia absorption. Specifically, the NH₃ absorption capacity is enhanced by ca. 18.1–36.9% when a small amount of metal chlorides, such as MgCl₂, MnCl₂ etc., are added into a DES composed of resorcinol (Res) and ethylene glycol (EG). To our knowledge, the MgCl₂/Res/EG (0.1:1:2) DES outperforms most of the reported DESs. The excellent NH₃ absorption performances of metal–containing DESs have been attributed to the synergy of Lewis acid–base and hydrogen bonding interactions. Additionally, good reversibility and high NH₃/CO₂ selectivity are achieved over the MgCl₂/Res/EG (0.1:1:2) DES, which enables it to be a potential NH₃ absorber for further investigations.     

Cycling stability and adsorption mechanism at room temperature of the upscaled Ni-doped hierarchical carbon scaffold

Hydrogen adsorption performance and mechanism upon cycling of the upscaled Ni-doped hierarchical carbon scaffold (HCS) are investigated. Upon 22 hydrogen ad/desorption cycles (T = 25–50 °C and p (H₂) = 1–50 bar), the upscaled Ni-doped HCS shows excellent cycling stability with gravimetric capacity of up to 1.51 wt % H₂. This is due to mechanical stability of HCS and good distribution of Ni nanoparticles. Hydrogen adsorption mechanism of Ni-doped HCS upon cycling is experimentally and theoretically characterized. Besides dissociative adsorption onto the surface, hydrogen diffusion into the lattice structure of Ni is observed. The latter enhances with the number of ad/desorption cycles and alters the electron sharing mechanisms between Ni and H during adsorption.     

Sulfur doped biocarbon obtained from Sargassum spp. for the oxygen reduction reaction

Sulfured doped carbon electrocatalysts is synthesized from the waste biomass Sargassum spp. Two doping procedures are examined to determine which is better for Oxygen Reduction Reaction (ORR); one by doping biocarbon obtained from the pyrolysis of the biomass and the second through a process of in situ doping in autoclave. The electrocatalyst are obtained from pyrolysis of the sample at 700 °C, which is finally characterized as a metal free electrocatalyst for the ORR. The electrocatalyst are characterized by BET surface area analysis, Raman spectroscopy, X-ray Photoelectron Spectroscopy (XPS) and the electrochemical characterization is determined in 0.1 M KOH. The sample SSKPT-1 exhibits a promising electrocatalytic activity with an onset potential of 0.896 V vs RHE and a current density of 5 mA cm^?2 (at 0.2 V vs. RHE) which could be partly attributed to its high BET surface area of 2755 m² g^?1.     

Effects of different metal corrosion inhibitors on hydrogen suppression and film formation with Mg–Zn alloy dust in NaCl solutions

To improve the safety of wet dust removal systems for processing magnesium-based alloys, a new method is proposed for preventing hydrogen generation. In this paper, hydrogen generation by Mg–Zn alloy dust was inhibited with six common metal corrosion inhibitors. The results showed that sodium dodecylbenzene sulfonate was the best hydrogen inhibitor, while CeCl₃ enhanced hydrogen precipitation. The film-forming stability of sodium dodecylbenzene sulfonate was tested with different contents, temperatures, Cl^? concentrations and perturbation rates. The results showed that this inhibitor formed stable protective films on the surfaces of Mg–Zn alloy particles, and adsorption followed the Langmuir adsorption model.     

Sorption kinetics in metal hydrides by leaky coating

The 3D geometry of a hydrogen absorbing metal grain (Pd) is mimicked by a membrane made of the metal with identical properties, which is sealed on one side with a hydrogen semi-impermeable surface (Cu). The hydrogen loss through the sealed membrane surface is negligible, i.e., the hydrogen uptake measurement is that of a bulk material (Sieverts measurement), but the surface desorbs sufficient hydrogen to be detected by a mass spectrometer. With this, two independent spatial and temporal kinetic properties are defined which allow the reconstruction of the time dependent hydrogen distribution inside the membrane. As proof of concept, the mechanism of hydride formation in Pd is analyzed, corroborating the formation and growth of incoherent interfaces during hydrogen sorption.     

Hydrangea like composite catalysts of ultrathin Mo2S3 nanosheets assembled on N,S-dual-doped graphitic biocarbon spheres with highly electrocatalytic activity for HER

Water electrolysis is the most clean and high-efficiency technology for production of hydrogen, an ultimate clean energy in future. Highly efficient non-noble electrocatalysts for hydrogen evolution reaction (HER) are desirable for large scale production of hydrogen by water electrolysis. Especially, exposing as many active sites as possible is a vital way to improve activities of the catalysts. Herein, a series of new hydrangea like composite catalysts of ultrathin Mo₂S₃ nanosheets assembled uprightly and interlacedly on N, S-dual-doped graphitic biocarbon spheres were facilely prepared. The unique structure endowed the catalysts highly exposed edge active sites and prominently high activities for HER. Especially, the optimized catalyst Mo₂S₃/NSCS-50 exhibited as low as 106 mV of overpotential at 10 mA/cm² (denoted as ?₁₀). The catalyst also showed low Tafel slope of 53 mV/dec, low electron transfer resistance of 34 Ω and high stability evidenced by the result that the current density only attenuated 11.7% after 10 h i-t test. The catalyst has shown broad prospect for commercial application in water electrolysis.     

Wavelength-dependent photoactivity of ZnxCd1−xS and ZnCo2O4/ZnxCd1−xS for H2 and H2O2 production

Zinc cadmium sulfide (Zn_xCd_1?xS) is a good photocatalyst for hydrogen evolution reaction (HER), but an optimum x (x_m) at which a maximum HER rate is reached varies from one report to another. In this work, we examine the effect of light wavelength, not only for the HER to H₂ in the presence of Na₂S and Na₂SO₃, but also for oxygen reduction reaction (ORR) without addition of any sacrifices. For the HER under a 365 and 420 nm LED lamp, the x_m were 0.9 and 0.7, respectively. For the HER under a 330 and 395–515 nm cut-off xenon lamp, the x_m were 0.7 and 0.5, respectively. For the ORR under a 420 nm cut-off halogen lamp, a maximum production of H₂O₂ was observed at x = 0.3. Furthermore, after 4% ZnCo₂O₄ loading, Zn_xCd_1?xS had an increased activity and stability, either for the HER or for the ORR. Through a (photo)electrochemical measurement, it is proposed that the photocatalytic activity of Zn_xCd_1?xS is determined by its light absorptivity and electron reactivity. The improved performance of n-type Zn_xCd_1?xS by p-type ZnCo₂O₄ is due to formation of a p-n junction, promoting the HER (ORR) on Zn_xCd_1?xS, and the sulfide (water) oxidation on ZnCo₂O₄. This work highlights that Zn_xCd_1-xS is a promising photocatalyst for H₂ and H₂O₂ production, respectively.