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A new lightweight magnesia refractory for working linings of high-temperature furnaces was prepared by using microporous magnesia aggregates instead of conventional dense magnesia aggregates. The median pore size of the microporous magnesia aggregates was 2.97 μm, while the apparent porosities of the microporous and dense aggregates were 33.3% and 5.5%, respectively. The phase composition, microstructures, fracture behaviors and strengths at room and high temperature of the lightweight magnesia refractory in comparison with those of the dense one were measured by means of XRD, SEM and three-point bending instrument. After the dense aggregates were replaced by the microporous ones, a better aggregate/matrix interface bonding was observed and the fracture mode changed from intergranular to transgranular fracture, which significantly improved the mechanical properties. Thus, the lightweight magnesia refractories had a lower bulk density of 11.8%, a higher apparent porosity of 56.2% as well as a higher flexural strength at room and high temperature of 48.4% and 160.0% comparing with the dense one, respectively.

Mullite-corundum foamed ceramics were prepared by direct-foaming method using white clay and industrial alumina as raw materials, and micro-pore-foaming agent (MPFA, the main composition was sodium dodecyl benzene sulfonate) as foaming agent. Effect of the MPFA addition on the phase compositions, microstructures and physical properties of the foamed ceramics were investigated by X-ray diffractometer (XRD), scanning electron microscopy (SEM) and energy dispersive spectrometer (EDS), etc. The results showed that the specimens fired at 1500 °C mainly consisted of needle-like mullite, corundum, and a small amount of glass phase. The MPFA decreased the viscosities and then increased the volume expansion of foamed slurries. Meanwhile, the adding of the MPFA caused the increases of apparent porosities and average pore sizes, and the decrease of strengths of the fired specimens. The optimized product was a specimen with 1.0 wt% MPFA fired at 1500 °C which had a high porosity of 73.7%, a proper compressive strength of 3.05 MPa, a low thermal conductivity of 0.287 W/(mK) (1000 °C) and a positive reheating linear change. Based on the experimental dates, an emendatory GE model was presented, which could predict accurately the effective thermal conductivity at 1000 °C of the mullite-corundum foamed ceramics with different pore characteristics.

This study presents a new lightweight corundum refractory (LCR) used for working linings of high-temperature furnaces. The LCR contained microporous corundum aggregates replacing tabular corundum aggregates in traditional corundum refractories (TCR). The median pore size of the microporous corundum aggregates was 4.20 μm, while the bulk density was 20.3% lower than that of the tabular corundum aggregates. The microstructure, cold modulus of rupture (CMOR) and fracture behavior of the LCR in comparison with those of the TCR were analyzed by mercury porosimetry, SEM and three-point bending tests. The results showed that the LCR had a better bonding at the interface between the microporous corundum aggregates and the matrix, which increased the percentage of crack propagation within the aggregates. Thus, the mechanical properties of the LCR was effectively enhanced. Compared with the TCR, the LCR had an 8.2% lower bulk density, while a 64.9% higher CMOR and a 38.2% higher fracture energy were achieved.

Brucite is an alternative magnesium precursor for magnesia castables. The hydration process of brucite-microsilica suspensions at 50 °C was firstly studied to identify the magnesium-silicate-hydrate (M-S-H) formation. The existence of M-S-H was dependent on the characteristics of brucite. The brucite with smaller grain size exhibited higher reactivity and favored the formation of M-S-H. The early strength of magnesia castables with addition of the 1 wt% reactive brucite powder was increased, which was related to the modified microstructure via filling effect of brucite fine particles and the formation of M-S-H. Explosion resistance of castables was improved as well attributed to the enhanced early strength and the M-S-H phase in the presence of reactive brucite. Besides, the facilitated formation of forsterite bonding phase in the brucite containing castables during firing process and the thermal-mechanical strength such as hot modulus of rupture and refractoriness under load were significantly increased.

In this paper, the influence of phase transformation on the properties and fracture behaviour of fused silica refractory was investigated. The virgin fused silica refractory is amorphous, and possible failure is attributed to the propagation of a single crack in the structure. Due to the crystallization and phase transformation of low-/high- temperature cristobalite subpolymorphs occurring during the heat treatment, microcracks are formed especially in the matrix and at the grain boundary. This microcracking enables the development of sizable fracture process zone, which is responsible for the increase of specific fracture energy even with the decrease of strength. Therefore, the heat-treated specimens exhibit lower brittleness and higher strain tolerance before failure compared with the virgin fused silica refractory. All of these properties represent a better thermal shock resistance. Furthermore, microcracking causes a characteristic temperature dependence of Young’s Modulus due to phase transformation and partial crack closure at increased temperatures.

In this study, four mullite foam ceramics with porous struts and low thermal conductivities, were prepared by direct-foaming method from white clay and industrial alumina with the addition of sodium carboxymethyl cellulose (CMC) as foam stabilising agent. The effect of the CMC addition on the phase composition, pore characteristics, and strength was analysed through XRD, SEM and EDS, etc. The great part of struts for the foam ceramics was the needle-like mullite, the rest was the minor corundum and quartz. The addition of CMC decreased the apparent porosity of foam ceramics and pore area fractions of their struts, while the phase composition was nearly unaffected. Furthermore, the compressive strengths and the thermal conductivities of the foams ceramics increased. The optimized product contained 0.15 wt% CMC, which combined a high porosity of 81.3%, shown a low thermal conductivity of 0.095 W/(mK) (at 350 °C) and a minor positive reheating linear change.

Interleukin-17 (IL-17) is a cytokine family that includes 6 members, IL-17A through IL-17F, most of them are reported to have pro-inflammatory role. Through binding to their receptors (IL-17Rs), IL-17 activates the intracellular signalling pathways to play an important role in autoimmune diseases, including rheumatoid arthritis (RA) and multiple sclerosis (MS). Ischaemic stroke is a complex pathophysiological process mainly caused by regional cerebral ischaemia. Inflammatory factors contribute to the physiological process of stroke that leads to poor prognosis. IL-17 plays a crucial role in promoting inflammatory response and inducing secondary injury in post-stroke. Though immune cells and inflammatory factors have been reported to be involved in the damage of stroke, the functions of IL-17 in this process need to be elucidated. This review focuses on the pathological modulation and the mechanism of IL-17 family in ischaemic stroke and seeking to provide new insights for future therapies.

To explore the efficacy and safety of sorafenib combined with transarterial chemoembolization (TACE) in the treatment of advanced hepatocellular carcinoma.118 patients with advanced hepatocellular carcinoma treated in our hospital from June 2014 to June 2016 were collected and randomly divided into the Sorafenib+TACE group (treated with Sorafenib combined with TACE, n=59) and the TACE group (n=59). The clinical efficacy, the changes in levels of serum vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF) and alpha fetoprotein (AFP) before and after treatment, adverse reactions and postoperative survival of patients were observed and recorded.The objective response rate (ORR) and the disease control rate (DCR) were 55.9% (33/59) and 86.4% (51/59) in the Sorafenib+TACE group, and 37.3% (22/59) and 67.8% (40/59) in the TACE group. Both ORR and DCR in the Sorafenib+TACE group were significantly superior to those in the TACE group (p=0.022, p=0.027). Main adverse reactions after treatment included myelosuppression, fever, rash, gastrointestinal reactions, hepatalgia, hypertension and hand-foot syndrome, mostly of grade I-II, which were all improved after dose reduction and symptomatic treatment. The incidence rates of rash, diarrhea, hypertension and hand-foot syndrome in the Sorafenib+TACE group were obviously higher than those in the TACE group (p0.001, p=0.002, p=0.002, p0.001). The levels of serum VEGF, bFGF and AFP declined significantly in both groups after treatment compared with those before treatment (p=0.013, p0.001, p0.001), while they were evidently lower in the Sorafenib+TACE group than in the TACE group after treatment (p0.001, p=0.016, p0.001). Follow-up results showed that the overall survival in the Sorafenib+TACE group was significantly longer than in the TACE group (p=0.030).Compared with TACE alone, Sorafenib combined with TACE can significantly improve ORR and DCR, obviously reduce the levels of serum VEGF, bFGF and AFP, and prolong the survival of patients with advanced hepatocellular carcinoma, while the adverse reactions are tolerable, so it is worthy of clinical popularization and application.

This study investigates five lightweight corundum-magnesium aluminate spinel castables (LCSC) which consisted of porous corundum-spinel aggregates and matrices with 0–2.8 wt% silicon carbide (SiC). The effect of the SiC powder content (SPC) in the matrix on the microstructure, strength, thermal conductivity and slag resistance was analyzed by XRD, SEM and EDS as well as by the thermochemical software FactSage. The addition of SiC powder resulted in a significantly improved interface bonding between the porous aggregates and the matrix enhancing the strength and slag resistance. Whereas the thermal conductivity at 300 °C and 500 °C remained unchanged, it increased significantly at 800 °C and 1000 °C. The optimized LCSC contained 1.9 wt% SiC powder which combined a suitable apparent porosity (32.5%), a low bulk density (2.41 g/cm3), a high flexural strength (17.62 MPa), a high compressive strength (100.76 MPa), a low thermal conductivity (0.978 W/m·K, 1000 °C) and a high slag resistance.

This study presents a new lightweight periclase-magnesium alumina spinel castable (LPSC) for the working lining of steel ladles using porous periclase-spinel aggregates to replace conventional dense magnesia aggregates. The porous periclase-spinel aggregates were produced by an in-situ decomposition technique resulting in an apparent porosity of 23.3% and a median pore size of 5.66 μm. Scanning electron microscopy revealed a better porous aggregate/matrix interface bonding in the LPSC, which significantly improved its strength and thermal shock resistance. Additionally, the higher amount of micropores of the porous aggregates in the LPSC absorbed more penetrated slag from the matrix, which enhanced the slag resistance. Thus, compared with conventional castables, the LPSC had a lower bulk density of 9.2–10.8% and a lower thermal conductivity of 18.8% (1000 °C) while at the same time a higher strength, thermal shock resistance and slag resistance was achieved.

In order to accelerate the formation of magnesium-silicate-hydrate gel (M-S-H), the sodium metasilicate was added into the MgO-SiO 2 slurries. The effect of sodium metasilicate on the hydration process of MgO-SiO 2 slurries was investigated in this work. It required a relatively small amount of sodium metasilicate to facilitate the formation of M-S-H and to surpress the brucite formation. In the early 24 h, the M-S-H formed quickly due to the high concentration of magnesium ions and silicate species in solutions. With the further increasing of curing time, the M-S-H gel phase continuously grew. Furthermore, the sufficient silicate ions amount was favorable for the transformation of newly formed brucite to the M-S-H phase. The addition of sodium metasilicate influenced not only the reaction process but also the morphology of hydrates. Instead of the yolk-shell structure, the flower-like and stacked sheet-like M-S-H formed in the presence of sodium metasilicate.

The microcrack network that develops during the cooling stage of magnesia spinel refractories production process contributes to its heterogeneity. To simulate the fracture process of a magnesia spinel refractory subjected to a wedge splitting test, a heterogeneous continuum model with random distribution of the properties was developed. The tortuous crack path and fracture process development were investigated numerically and compared to experimental digital image correlation observation. Bilinear strain softening curves were used to depict the fracture behaviour of the refractories. With an inverse identification approach, the fracture parameters including tensile strength, ultimate displacement, and total specific fracture energy were obtained. The method is the basis for a realistic simulation of crack propagation in refractories used for industrial applications.

In this paper, the formation of the fracture process zone (FPZ) of industrially produced magnesia spinel and magnesia refractories was analysed using digital image correlation (DIC). Compared to pure magnesia materials, the magnesia spinel materials exhibited a higher amount of microcracks, causing a larger FPZ. A critical displacement, where the cohesive stress between the crack faces decreases to zero, is determined by analysing the development of the localized zone. Critical displacement determined from the changes of the FPZ width and length is used to determine the onset of macro-cracking and locate the crack tip. The development of the fracture process zone for a magnesia spinel initiates before reaching the maximum load, and the onset of the macro-crack is in the post-peak region. The FPZ size increases until the formation of a macro-crack takes place, but decreases afterwards. For the magnesia refractory, no pronounced FPZ could be detected.

Highlights • The arterial supply of the future liver remnant (FLR) may be important for the FLR growth. • Huge hepatocellular carcinoma (HCC) can cause blood-stream steal from the FLR, which can result in ALPPS failure. • Transarterial embolization (TAE) of HCC can salvage failed Stage I ALPPS. • TAE can induce significant hypertrophy of FLR. • TAE-salvaged ALPPS may be suitable for huge HCC with chronic liver disease., Introduction The degree of hypertrophy of the future liver remnant (FLR) induced by associating liver partition and portal vein ligation for staged hepatectomy (ALPPS) in patients with HCC and chronic liver disease is often limited as compared with patients with a healthy liver. Presentation of case We reported a 53-year-old male who had a huge HCC (14.8 × 12 × 9.4 cm) arising from a background of hepatitis B liver fibrosis (METAVIR score F3). The ratio of the FLR/standard liver volume (SLV) was 23.8%. After stage I ALPPS, volumetric assessment on postoperative day (POD) 7 and 13 showed insufficient FLR hypertrophy (FLR/SLV: 28.7% and 30.7%, respectively). A postoperative computed tomographic 3D reconstruction and hepatic angiography showed steal of arterial blood from the FLR to the huge tumour in the right liver. Salvage transhepatic arterial embolization (TAE) was performed to block the major arterial blood supply to the tumour on POD 13. The FLR/SLV increased to 42.5% in 7 days. Stage II ALPPS consisting of right trisectionectomy was successfully performed. Discussion Salvage TAE which blocked the main arterial blood supply to the huge HCC improved the arterial supply with subsequent adequate and fast hypertrophy of the FLR to allow trisectionectomy in stage II ALPPS to be carried out. Conclusion Salvage TAE after failed stage I ALPPS with inadequate hypertrophy of the FLR allowed trisectionectomy in stage II ALPPS to be carried out in a patient with a huge HCC with chronic liver disease.

In this study, the degradation mechanisms of dense periclase-magnesium aluminate spinel refractory bricks used in the upper transition zone of cement rotary kilns were investigated by XRD, SEM and EDS. And the results indicated that the damage of the used brick was main due to the structural spalling as well as the formation and extension of cracks, caused by the corrosion of cement clinker, the deposition of alkali salts and thermal stress resulted from changing temperature field. The bricks reacted with the cement clinker forming a liquid phase at the reacting interface, and then the penetration of this liquid phase by reaction sintering altered the microstructure and compositions of bricks. Additionally, the constantly changing temperature field and the precipitation of alkali salts with the high thermal expansion coefficient in colder zones led to tremendous thermomechanical stress. Thus, joint effects of these factors caused the structural spalling and deterioration of refractory linings.

Foamed mullite-SiC ceramics were prepared by using white clay, industrial alumina and silicon powder as raw materials. The effects of the clay content on the phase composition, microstructure and thermal properties of foamed ceramics were investigated by X-ray diffractometer (XRD), scanning electron microscopy (SEM) and energy dispersive spectrometer (EDS). The fired foamed mullite-SiC ceramics contained mullite, corundum and β-SiC. With an increase of clay content, the apparent porosity decreased, while the compressive strength and thermal conductivity increased. The optimized composition had a clay content of 44 wt% clay, which yield a high porosity of 72.9%, an excellent compressive strength of 5.6 MPa and a low thermal conductivity of only 0.267 W/(m·K). An adjusted GE thermal conductivity model assuming an appropriate emissivity of 0.35 was highly capable to predict the effective thermal conductivities of the foamed mullite-SiC ceramics with different pore characteristics at 800 °C.

Only very few studies about the influence of cooling on the thermo-mechanical properties of heated rocks exist. This study focuses on high-speed heating followed by slow as well as rapid cooling of granite samples. Target temperatures of 400 °C and 800 °C were reached with heating rates of 200 °C/min, 300 °C/min and ISO 834 standard fire curve. Numerical simulations are used to investigate the temperature evolution inside the sample. The digital image correlation (DIC) technique was used to analyse the strain field evolution during air-cooling with furnace removed. DIC analysis reveals that the microcracks induced by high-speed heating and high temperatures (i.e. 800 °C) can close progressively due to the material contraction during cooling. The closing of microcracks caused by shrinkage plays a more important role than cracking behaviour caused by thermal gradients (i.e. thermal shock). Both rapid (furnace removed) and slow (furnace in place) cooling do not show obvious influence on the stress-strain behaviours of granite samples heated to 400 °C. The samples heated to 800 °C with rapid cooling have a higher uniaxial compression strength than in slow cooling case. This indicates that the contraction effect during rapid cooling might be more intense than in slow cooling cases.

In order to evaluate the stability of aerobic granules in a toxic environment, this study discussed the influence of an aniline supplement on the properties and microbial community of aerobic granules. In the early stages of sequencing batch reactor (SBR) operation, an aniline supplement slightly affected the properties of the aerobic granules (strength, growth rate, SVI and so on). This effect was thereafter removed because of a change in the microbial community and the structure of aerobic granules: with the present of aniline, microbes with biodegradation ability appeared and gathered in the aerobic granules and the aerobic granules densified and settled faster as their SVI decreased to 35 mL/g and settling velocity increased to 41.56 m/h. When a synthetic waste water containing acetate as carbon source was used as influent, aniline (10-500 mg/L) could be degraded in 6 h, at a rate as high as 37.5 mg aniline/(L·h), with a removal rate in excess of 90%, while the effluent COD fell below 100 mg/L from the initial about 2000 mg/L. The aerobic granules cultured by acetate were compact, stable and resistant to aniline.

A two-step strategic approach was proposed to synthesize three-dimensional Co3O4 nanoarrays fabricated on a Cu substrate surface with a Ni layer as the interface. Firstly, a Ni-nanoseed-layer was prepared on a Cu substrate by electrodepositing Ni. And then Co3O4 nanoarrays were in situ grown on the Ni layer via a hydrothermal synthesis. The as-obtained materials were used directly as anodes for Li-ion batteries, and the electrodes maintained a high capacity up to 1150 mA h g−1 at 0.1 C after 30 cycles, and showed an excellent cycling stability and rate capability. The good electrochemical performance is owing to the pre-electrodeposited Ni-nanoseed-layer, because the Ni layer could improve the mechanical adhesion between Co3O4 nanoarrays and substrates effectively and increase the conductivity of anodes, without applying binders or conductive additives. This strategic in situ synthesis method will probably open a new avenue for the development of integrated electrode materials for high-performance Li-ion batteries.

Multi-walled carbon nanotubes (MWNTs) functionalized with poly(dopamine) (PDA) were found to cause the immobilization of silver nanoparticles on the surface. The PDA functional layer not only improved the dispersion of MWNTs in aqueous solution, but also was used as a platform for subsequent silver nanoparticle immobilization. The surface morphology of the functionalized MWNTs was observed by high-resolution transmission electron microscopy. The results showed that PDA layers with controlled thickness on the nanometer scale were formed on MWNT surfaces by in situ spontaneous oxidative polymerization of dopamine, and that high-density of homogeneously dispersed spherical silver nanoparticles with sizes of 3–4 nm were immobilized on their outer surface. The space between spherical silver nanoparticles is less than 10 nm. Both X-ray photoelectron spectroscopy and X-ray diffraction results showed that the Ag nanoparticles on the surface of hybrids exist in the zero valent state.