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The effects of in-situ synthesis columnar mullite and pore structure on the hot modulus of rupture (HMOR), thermal shock resistance and corrosion resistance of corundum castables have been investigated in this paper. When 2% nano silica was added, the pore diameters of castables could be decreased to 15 nm (at 110 °C), 1 μm (1100 °C) and 6 μm (1500 °C), respectively. The corresponding reducing magnitude of pore size is 98.5%, 83.3% and 33.3%. The HMOR of castables fired at 1500 °C increased by 110% to 3.64 MPa. Furthermore, after three thermal shock cycles, the residual strength ratio of castables increased from 5.2% to 15.3%. A large amount of cross-distributed columnar mullite was formed between nano silica and α-Al2O3 by the two-dimensional nucleation mechanism, which remarkably enhanced the high temperature properties. The penetration index reduced from 30.86% to 19.88%, suggesting that smaller pore size and higher viscosity had a great influence to the penetration process.

Protecting the staff on site from exposure risk to toxic industrial chemicals (TICs) in an efficient way is of great significance. However, simultaneous removal of multicomponent TICs with different physical and chemical properties is a challenge for porous carbon materials. In this work, Cu-carbon beads with tailored porous structure and chemical property were synthesized via phase inversion-carbonization (PIC) route. The in-situ introduction of copper species was accomplished via coupling solidification-reduction of copper species and PIC process. The obtained Cu-carbon beads possessed uniform spherical shape (Φ1.3 mm) with good mechanical strength, developed porous structure and abundant chemical groups. Three kinds of TICs with different chemical properties, i.e. benzene (nonpolar), ethanol (polar) and H2S (inorganic), were selected as probes to evaluate the simultaneous elimination performance of Cu-carbon beads. The optimized Cu-beads-3 exhibited excellent performance for multicomponent TICs with capacities of 491.9 mg benzene/g, 192.1 mg ethanol/g and 76.2 mg H2S/g, representing 74.0, 60.3 and 99.2% capacities compared with monocomponent TICs. The enhanced adsorption of H2S were ascribed to chemisorption of copper species and basic groups on Cu-carbon beads. These results indicated that Cu-carbon beads would be a promising candidate for the simultaneous elimination of TICs with different chemical properties.

It is of great significance to protect workers from Sulphur compounds in efficient ways during the regular overhaul or emergency management. Efficient adsorbent with low pressure drop is highly desired in protective equipment. In this work, Cu-ordered mesoporous carbon foams (MeCF) were prepared through the sol-gel casting and wet-impregnation process. The obtained carbon foams possessed typical sponge structure with high porosity and copper particles attached on the skeleton. The characterization on morphology, structure and property illustrated that the presence of mesopores could effectively inhibit the growth of copper particle on MeCF. As the representative of Sulphur compounds, H

Porous matrix immobilization is considered as an effective approach to address the engineering challenges during practical application of nanoadsorbent. In this work, solid and hollow hydrous Zirconium (IV) oxide (ZrO2·nH2O, SHZO and HHZO) nanoparticles were enwrapped into millimeter-level beads by polyethersulfone through a mild liquid-liquid phase inversion technique. The beads possess asymmetric and hierarchical structure with an exterior porous surface dense layer and numerous inner interpenetrating finger-like channels, which promote the transportation of molecule and prevent the leaching of nanoadsorbents. As compared to SHZO beads, HHZO beads exhibited higher efficient adsorption capacity toward Pb (II) (104 mg·g−1), which could remain at 94% of HHZO nanoparticles. The effects of pH, the stability of adsorbents and coexisting ionic are further explored in detail. The Pb (II) removal mechanism is further studied by the EDS mapping, XPS, FTIR measurements, further indicating the surface hydroxyl groups played a key role in the adsorption process. Fixed-bed column sorption experiment and in situ regeneration were conducted so as to examine the practical application of the beads. Therefore, this kind of beads indicated the potential practical application in industrial wastewater treatment.

Simultaneous removal of multi-component pollutants from atmosphere is crucial for personal protection. Herein, porous carbon spheres (PCSs) with 1.2 mm diameter were prepared through the phase inversion route followed by carbonization using g-C3N4 and PVDF as precursors. The structure and chemical property of PCSs can be tailored via controlling the content of g-C3N4 due to its dual-function of template and nitrogen source. The resultant PCSs possess high surface areas, rich nitrogen content and favorable micro/meso/macro hierarchical porous structure, which are highly desired for simultaneous removal of benzene and H2S. The dynamic adsorption behaviors for benzene and H2S were investigated to examine the protective performance. Owing to the abundant porous structure and chemical polarity, PCSs extend the protective performance for H2S under retention of adsorption performance for benzene. The promotion on adsorption performance for H2S from mixture could be attributed to the change of electron distribution on nitrogen atom caused by the adsorbed benzene. The adsorption kinetic confirmed the enhancement on mass transfer ascribed to meso/macro hierarchical porous structure. These results revel that PCSs would be a promising adsorbent in personal protective equipment for VOCs and TICs.

In this work, nitrogen doped hollow carbon spheres (NHCS) were synthesized via modified “silica-assistant” route and further examined as adsorbents for the removal of benzene, which is a typical volatile organic compounds (VOCs). To understand the structure and composition on benzene removal, solid carbon spheres (SCS), nitrogen doped solid carbon spheres (NSCS) and hollow carbon spheres (HCS), were also prepared for comparison. The structure and morphology characterization revealed that the resultant carbon spheres possess uniform spherical shape, abundant micropores and mesopores with solid or hollow structure and high pore volume. Combined with Raman and XPS spectra, the composition of carbon spheres was successfully tailored via introduction of nitrogen atom into carbon matrix. To present the removal performance of carbon spheres for VOCs, the dynamic adsorption behavior was evaluated. Attributed to the combined effect of hollow structure and nitrogen doping, NHCS presents remarkable dynamic adsorption performance for benzene vapor with adsorption capacity of 766 mg/g. The enhancement on desorption behaviors resulting from hollow structure of HCS is confirmed when compared with SCS. Carbon spheres exhibit good regenerability based on desorption experiment. The mechanism of enhanced adsorption performance caused by nitrogen doping is clarified as the combined action of adjustment on porous structure and composition. These results indicate that NHCS would become a promising candidate for VOCs removal.

It is of great significance to protect workers from Sulphur compounds in efficient ways during the regular overhaul or emergency management. Efficient adsorbent with low pressure drop is highly desired in protective equipment. In this work, Cu-ordered mesoporous carbon foams (MeCF) were prepared through the sol-gel casting and wet-impregnation process. The obtained carbon foams possessed typical sponge structure with high porosity and copper particles attached on the skeleton. The characterization on morphology, structure and property illustrated that the presence of mesopores could effectively inhibit the growth of copper particle on MeCF. As the representative of Sulphur compounds, H2S was selected to evaluate the protective performance. Porous copper carbon foams with moderate loading rate (3%) of copper species exhibited longest breakthrough time and largest adsorption capacity. Compared with the microporous foams, MeCF-3 displayed promoted protective performance with breakthrough time of 54.7 min and adsorption capacity of 27.8 mg/g. The enhancement on capabilities was attributed to small-sized copper species with high activity and better dispersion on mesoporous structure. These results reveled that MeCF with sponge frameworks, developed mesoporous structure and high dispersion of active species would be a promising candidate for the elimination of H2S in personal protective equipment.

OBJECTIVE: To evaluate the effect of remote controlled injection manipulator system (RCIM) assisted percutaneous kyphoplasty (PKP) for the treatment of rupture of posterior vertebral osteoporotic vertebral fracture by comparing with intermittent hand bolus injection of bone cement during operation. METHODS: Between September 2010 and January 2016, a retrospective analysis was made on the clinical data of 48 senile patients with single segment rupture of the posterior vertebral osteoporotic thoracolumbar fracture undergoing PKP who accorded with the inclusion criteria. Of 48 patients, 22 received intermittent hand bolus injection of bone cement in the control group, and 26 received RCIM assisted bone cement perfusion in the trial group. There was no significant difference in age, gender, duration of disease, causes of injury, implicated vertebral bodies, bone mineral density T value, pain duration, preoperative visual analogue scale (VAS), relative vertebral body height in the anterior part, and posterior convex Cobb angle between groups (P>0.05). The bone cement perfusion time, the radiation dose of both doctors and patients, and the amount of bone cement injection were recorded; treatment effects were evaluated based on VAS score, posterior convex Cobb angle, relative ver-tebral body height in the anterior part, ratios of bone cement diffusion area and bone cement leakage rate. RESULTS: The patients were followed up for 6 months; no complications of toxic effect of bone cement, spinal cord or nerve root injuries, infection and vascular embolization occurred during follow-up period. There was no significant difference in bone cement injection amount and radiation dose of doctors between groups (P>0.05), but bone cement perfusion time, ratios of bone cement diffusion area, and radiation dose of patients were significantly lower in the trial group than the control group (P0.05). CONCLUSION: Satisfactory effectiveness can be achieved by applying RCIM assisted PKP for the treatment of rupture of posterior vertebral osteoporotic vertebral fracture. RCIM can shorten perfusion time, reduce radiation dose, and decrease incidence of bone cement leakage.

The effect of adding Fe nanosheets on the microstructure of phenol resin and low-carbon MgO–C refractories was investigated. The results indicate that well-crystallised carbon nanotubes (CNTs) of 50–100 nm in diameter and of micrometre scale in length could be generated at 1000 °C. The yield of CNTs decreases and the diameter of CNTs increases significantly as the coking temperature increases. The growth mechanism of vapour–solid (V–S) is transformed into the vapour–liquid–solid (V–L–S) mechanism at 1200 °C for CNTs in low-carbon MgO–C refractories. The mechanical properties and thermal shock resistance at 1000–1400 °C of the specimens with 0.5 wt% Fe nanosheets are greatly improved compared with specimens without Fe nanosheets. The largest magnitudes in the cold crushing strength (CCS), the cold modulus of rupture (CMOR), the hot modulus of rupture (HMOR), and the residual cold modulus of rupture (CMOR st ) are 25%, 44%, 24%, and 30%, respectively. The results are attributed to in situ formation of CNTs and the subsequent generation of bridging and crack deflection mechanisms in the matrix. However, as the coking temperature increases, the yield of the CNTs becomes lower and their diameter becomes larger. Thus, the favourable contribution on the thermal shock resistance decreases gradually.

Upon application of nano-sized metallic Ni particles as catalyst, the in-situ synthesis mechanism of spinel whiskers in MgO–C refractories was studied. Their phase composition and morphology were determined by means of X-ray diffraction and scanning electron microscopy supported by energy dispersive spectroscopy. The results show that when the catalyst of nano-sized Ni was added in MgO–C refractories, the granular MgAl2O4 (MA) spinels transformed into the shape of whiskers at 1 200 °C. The presence of Ni catalyst can accelerate the generation of Mg vapor, which can react with Al vapor to form MA spinel whiskers. Through dissolution and precipitation, MA spinel crystals nucleate directly and grow into whiskers from the catalytic droplets of nano-sized metallic Ni particles. The growth of spinel whiskers follows a typical vapor–liquid–solid (V–L–S) growth mechanism.

Using nickel nitrate as catalyst precursor, a cost effective method for large scale preparation of carbon nanotubes (CNTs) was investigated through catalytic pyrolysis of phenol resin in the temperature range of 600–1200°C under an Ar atmosphere. The morphology and structure of pyrolysed resin were characterised by X-ray diffraction, scanning electron microscope, transmission electron microscope and energy dispersive X-ray spectroscopy. The results show that the morphology and structure of CNTs depend on pyrolysis temperature, and the starting growth temperature of CNTs is ∼600°C. When the pyrolysis temperature is raised, the length and crystallinity of CNTs increase remarkably. High aspect ratio and well crystallised CNTs with average diameter of about 50–60 nm and micrometer scale length could be obtained at 1000°C. Scanning electron microscopy and transmission electron microscopy analysis reveals that the catalyst particle was located at the top of each CNT, which indicates the tip growth mecha...

To evaluate the effectiveness of anterior lumbar interbody fusion (ALIF) with self-locked Cage in the treatment of central type lumbar intervertebral disc protrusion and recessive lumbar segmental instability.Between March 2010 and February 2012, 31 patients with central type lumbar intervertebral disc protrusion and recessive lumbar segmental instability were treated with decompression and ALIF assisted by self-locked Cage through the mini-incision and retroperitoneal approach. There were 20 males and 11 females with the mean age of 46 years (range, 34-58 years). And the disease duration ranged from 5 to 32 months (mean, 16 months). The lesion located at the L3,4 level in 2 cases, L4,5 in 20 cases, and L5, S1 in 9 cases. The operation time, intraoperative blood loss, bedridden time, hospitalization time, and complications were recorded. The effectiveness was evaluated by Oswestry disability index (ODI) and visual analogue scale (VAS). Lumbar X-ray films and three-dimensional CT scan were taken to evaluate the fusion and the variation of the height and Cobb angle of intervertebral space.The mean operation time was 102 minutes; the mean intraoperative blood loss was 121 mL; the mean bedridden time was 5 days; and the mean hospitalization time was 11 days. Intraoperative peritoneum tear and ascending lumbar vein tear, postoperative cerebrospinal fluid leakage, pain at donor site, and asymmetric elevated skin temperature of the lower extremity occurred in 2 cases, 1 case, 1 case, 4 cases, and 2 cases respectively, which were relieved after symptomatic treatment. All cases were followed up 12-28 months (mean, 20 months). No infection, recurrence, deep venous thrombosis, or retrograde ejaculation was observed after operation. MRI showed complete decompression at 3 months after operation. At last follow-up, the scores of ODI, VAS of lumbars and lower limbs, the intervertebral height, and Cobb angle were significantly improved when compared with preoperative ones (P0.05); CT scan showed bone fusion in all cases.The clinical outcome of ALIF with self-locked Cage through mini-incision and retroperitoneal approach is satisfactory in treatment of central type lumbar intervertebral disc protrusion and recessive lumbar segmental instability. It can retain the posterior spinal construction and has the advantages of less trauma and bleeding, immediate stability, high bone fusion rate, and so on.