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Objectives: To measure the expression of matrix metalloproteinase (MMP)-2, tissue inhibitor of matrix metalloproteinase inhibitor (TIMP)-2, and CD147 in mice with chronic liver injury induced by carbon tetrachloride after treatment with the traditional Chinese medicine (TCM) “Compound T11”. Method: Sixty male ICR mice were divided randomly into 6 groups of 10: control (C), model (M), low-dose treatment (LT; 50 mg/mL of Compound T11), medium-dose treatment (MT, 100 mg/mL), high-dose treatment (HT, 150 mg/mL), and positive drug treatment (YT, 67.5 mg/mL). Each group was modeled for 7 weeks. Groups M, LT, MT, HT, and YT were injected (s.c.) with 20% carbon tetrachloride diluted with olive oil, and group C was given olive oil in the same way twice a week. After modeling, the treatment groups were administered Compound T11 at the concentrations shown above by oral gavage daily for 2 weeks, while group C was given 0.5% carboxymethyl cellulose sodium. After the final treatment, mice were killed and their liver tissues were excised. Immunohistochemical staining was performed to measure the protein expression of MMP-2, TIMP-2, and CD147, and western blotting was used to measure the protein expression of MMP-2, TIMP-2, CD147, and α-smooth muscle actin (SMA). MMP-2, TIMP-2, and CD147 mRNA expression was determined by quantitative fluorescence real-time PCR. Results: Compound T11 increased the protein expression of MMP-2 and CD147 and decreased the protein expression of TIMP-2 and α-SMA. Conclusions: Treatment of chronic liver injury by TCM Compound T11 may be associated with changes to the expression of MMP-2 and CD147, and the inhibition of TIMP-2 expression.

Materials with opposite affinities toward oil and water have been extensively used to coat porous substrates for oil-water separation, but the applications of these materials have been limited by the need for complex coating processes as well as the short-term adherence of these materials onto different substrates under extreme conditions. As reported herein, the robust porous polyurethane hydrogel has been theoretically and structurally designed with ultralow-oil-adhesion properties which is free stand without depending on additional substrates. The combination of superhydrophilic properties along with the underwater superoleophobic behavior of this porous hydrogel allows gravity driven separations of oil-water mixtures, and its antiadhesion performance toward oil prevents undesirable oily fouling. The underwater superoleophobic properties were also illustrated by molecular dynamics simulation to understand the resisting effect of hydrated layers. The as-prepared porous hydrogel shows ultrahigh oil-water separation efficiencies of 99.9% for various oil-water mixtures, ranging from those containing viscous oils (pump oil and peanut oil) to organic solvents (n-hexane, n-hexadecane, and toluene). In addition, this hydrogel is durable even with exposure to various harsh conditions including acidic and basic media (pH 0-14) as well as exposure to mechanical abrasion. We believe that the combination of facile preparation, substrate independence, gravity driven separation, antifouling properties, high durability, as well as the outstanding separation flux and efficiency of this robust porous hydrogel will help to advance the design and application of materials in oil-water separation fields.

The underwater superoleophobicity of a coating is often caused by its preferential water affinity, which, however, normally weakens the substrate adhesion property. In this work, a new strategy is reported for achieving strong underwater adhesion between a well-designed amphiphilic polyurethane coating and a diverse range of substrates while also rendering the coating surface's superoleophobicity. When the coating, which is a mixture of an amphiphilic polyurethane and a water miscible solvent, is immersed in water, the hydrophobic segments aggregate to orientate and pile along the surface of substrates via a segment orientation mechanism triggered by solvent exchange with water penetration to exert strong adhesion. At the same time, the hydrophilic segments will physically crosslink to form a hydrogel coating, endowing the substrate with underwater superoleophobicity. This work provides a facile, versatile, and scalable approach for the future design of superoleophobic coatings in a water environment.

In the process of smelting and manufacturing, bearing steel inevitably have defects such as non-metallic inclusions. Moreover, inclusion geometry (type, quantity, size, distribution, and shape) has a significant effect on the fatigue failure of bearing steel. In order to study effect extent of the size and distribution of inclusion on the fatigue life of bearings, this paper uses the test high-speed rail bearings LY-Z028 to research and analysis. The micro-model of contact between single inclusion and the matrix is established, and then performs ANSYS simulation on stress concentration which caused by size of single inclusion and relative surface depth. Further, multiple linear regression method is used to compare the effect extent of these two factors on the fatigue life. The results show that size of single inclusion has a greater impact on the fatigue life than relative surface depth, which can provide an effective reference for smelting and production requirements.

The contact simulation model of high-speed railway train axle box bearing is simplified into a two-dimensional plane with an elastic semi-infinite body subjected to semi-elliptical cylindrical compressive stress in one direction. The ANSYS software was used to solve the effects of single inclusion size, the depth of the contact surface and the elastic modulus on dynamic shear stress and Von Mises stress of high-iron bearing subsurface, and compared with the calculation results of bearing material uniformity assumption. Using the modified Basquin equation, the relevant assumptions are made. The maximum Von Mises stress is used as the key stress for fatigue life calculation. The bearing fatigue life calculation method is established to study the influence of the inclusion size, the depth of the contact surface and the elastic modulus on the bearing fatigue life.

The porous Si-based ceramic core was prepared using injection method, where quartz glass powders were used as original materials and thermosetting silicon resin was used as plasticizer. The effect of sintering tem- perature and holding time on the properties of the samples were examined. It was found that the process of devitri- fication was accelerated with the increase of sintering temperature while the glass phase transforms into cristobalite gradually. When sintering temperature was at 1250℃, the amount of cristobalite increased with the extension of holding time. Linear shrinkage rate and weight loss of the samples slightly increased with the increase of sintering temperature. But the holding time showed less effect on linear shrinkage rate and weight loss of the samples. In fact, the weight loss of the sample was mainly caused by decomposition of silicon resin. The sample sintered at 1250 for ℃ 10 h showed linear shrinkage of 0.93%, the porosity of 32.8% and bending strength of 9.08 MPa.