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Jia-Ying Pan,1,* Yuan Chen,1,* Zhi-He Lin,1 Bo Lv,1 Lei Chen,2 Shao-Yan Feng1 1Department of Otorhinolaryngology, Head and Neck Surgery, The Fifth Affiliated Hospital of Sun Yat-sen University, Zhuhai, Guangdong, People’s Republic of China; 2Department of Neurosurgery, The Fifth Affiliated Hospital of Sun Yat-sen University, Zhuhai, Guangdong, People’s Republic of China*These authors contributed equally to this workCorrespondence: Shao-Yan Feng, Department of Otorhinolaryngology, Head and Neck Surgery, The Fifth Affiliated Hospital of Sun Yat-sen University, No. 52, Meihua East Road, Xiangzhou District, Zhuhai, 519000, People’s Republic of China, Tel +86-13626927889, Email fshaoy@mail.sysu.edu.cn Lei Chen, Department of Neurosurgery, The Fifth Affiliated Hospital of Sun Yat-sen University, Zhuhai, Guangdong, People’s Republic of China, Tel +86-13902878497, Email clzzzz@126.com; chenlei63@mail.sysu.edu.cnObjective: Sensorineural Hearing Loss (SNHL) is a representative human sensory impairment, few studies have paid attention to the correlation between the Triglyceride-Glucose (TyG) index and SNHL to date. We conducted this analysis to elucidate the correlation between the TyG index and pure tone hearing thresholds among US adults.Methods: Our analysis included 1226 adults (age range: 20 to 69 years old) from the 2015– 2016 National Health and Nutrition Examination Survey (NHANES) data. TyG index was scored into three quartiles. Weighted univariate analysis, weighted multivariate linear regression analyses as well as smooth curve fittings evaluated the associations between TyG index and pure tone hearing thresholds.Results: In the multiple regression analysis, the second tertile of TyG index was negatively associated with high-frequency hearing thresholds shifts. Furthermore, the non-linear relationships between TyG index and speech-frequency and high-frequency hearing thresholds were identified by smooth curve fittings. After adjusti

Zhi-He Liu,1 Lin Zhang,2 Fan-Jing Jing,1 Shu-Xin Xiao,1 Yan Gao,1 Hai-Yan Bian,1 Xia Zhao1 1Department of Hematology, The Affiliated Hospital of Qingdao University, Qingdao, 266000, Shandong, People’s Republic of China; 2Laboratory of Molecular Diagnosis and Regenerative Medicine, The Affiliated Hospital of Qingdao University, Qingdao, 266000, Shandong, People’s Republic of ChinaCorrespondence: Xia ZhaoDepartment of Hematology, The Affiliated Hospital of Qingdao University, 16 Jiangsu Road, Shinan District, Qingdao, 266000, Shandong, People’s Republic of ChinaTel/Fax +8653282911201Email alice-xia@163.comPurpose: The role of NLRP3 inflammasome in the progression of many diseases has been increasingly recognized. However, the function of this molecular assembly in the development and progression of B-cell non-Hodgkin’s lymphoma remains unclear.Patients and Methods: In this study, we investigated the polymorphisms in the NLRP3 inflammasome associated genes in 281 patients with B-cell non-Hodgkin’s lymphoma and 385 age- and gender-matched healthy controls.Results: We found that IL-18 (rs1946518) and NFκB-94 ins/del (rs28362491) contributed to susceptibility to B-cell non-Hodgkin’s lymphoma. Specifically, the allele “G” in IL-18 (rs1946518) and allele “ins” in NFκB-94 ins/del (rs28362491) were significantly associated with the risk of disease. The AA genotype of CARD8 (rs2043211) and the higher level of serum lactate dehydrogenase (LDH) led to statistically poorer B-cell non-Hodgkin’s lymphoma survival. Less frequent genotype TT of CARD8 (rs2043211) was observed in patients with higher LDH level, clinical stages III–IV of disease, and IPI 3– 5, although the relationship did not reach statistical significance. However, IPI is an independent prognostic factor for B-cell non-Hodgkin’s lymphoma.Conclusion: IL-18 (rs1946518) and NFκB-94 ins/del (rs28362491) gene polymorphisms appear to be the factors influencing the risk of B-cell non-Hodgkin’

In terms of secondary resource recovery and environmental impact, fly ash is attracting a great deal of attention in China. This study aimed to investigate the carbochlorination process of titanium oxide to recover titanium. The extraction kinetics mechanism of titanium oxide from fly ash was investigated at temperatures ranging from 850 to 1 050 degrees C. The effect of various experimental parameters was studied. The reactants and reaction residues were analysed by scanning electronic microscopy and chemical analysis. The results show that the best extraction efficiency of 91.66% was obtained at a temperature of 1 050 degrees C, a coking coal content of 34.64 wt.%, a pellet diameter of 8 mm, an average gas flow of 0.35 l/min, and a time of 120 min. The carbochlorination reaction of titanium oxide is controlled by the chemical reaction. The apparent activation energy is approximately 44.45 kJ/mol between 800 and 1 050 degrees C. (Authors.), In terms of secondary resource recovery and environmental impact, fly ash is attracting a great deal of attention in China. This study aimed to investigate the carbochlorination process of titanium oxide to recover titanium. The extraction kinetics mechanism of titanium oxide from fly ash was investigated at temperatures ranging from 850 to 1 050 degrees C. The effect of various experimental parameters was studied. The reactants and reaction residues were analysed by scanning electronic microscopy and chemical analysis. The results show that the best extraction efficiency of 91.66% was obtained at a temperature of 1 050 degrees C, a coking coal content of 34.64 wt.%, a pellet diameter of 8 mm, an average gas flow of 0.35 l/min, and a time of 120 min. The carbochlorination reaction of titanium oxide is controlled by the chemical reaction. The apparent activation energy is approximately 44.45 kJ/mol between 800 and 1 050 degrees C. (Authors.)

In the silicothermic process for Mg production about 5% of fines are produced after calcining and pelletising of dolomite which cannot be used, resulting in high energy consumption and costs. To investigate possible improvements to the process, pellets essentially comprising dolomite, 75Si-Fe reducing agent, fluorite catalyst and organic or organic/inorganic composite binder were prepared prior to the calcination stage. Dolomite per se was found to have a high sphericity k of 0.90, which is favourable for pelletising. The pellets prepared using the composite binder had a uniform particle size of 10-15 mm, a dropping strength of 2.5 times/0.5 m and a compressive strength of 80 N/pellet. Mg loss during the sintering process was about 0.2% and no Si was oxidised. The dolomite pellets had a high activity and stability which improved resource utilisation and reduced the energy consumption of calcining., In the silicothermic process for Mg production about 5% of fines are produced after calcining and pelletising of dolomite which cannot be used, resulting in high energy consumption and costs. To investigate possible improvements to the process, pellets essentially comprising dolomite, 75Si-Fe reducing agent, fluorite catalyst and organic or organic/inorganic composite binder were prepared prior to the calcination stage. Dolomite per se was found to have a high sphericity k of 0.90, which is favourable for pelletising. The pellets prepared using the composite binder had a uniform particle size of 10-15 mm, a dropping strength of 2.5 times/0.5 m and a compressive strength of 80 N/pellet. Mg loss during the sintering process was about 0.2% and no Si was oxidised. The dolomite pellets had a high activity and stability which improved resource utilisation and reduced the energy consumption of calcining.

A sample of diasporic bauxite from China's Henan province was pretreated by roasting in a magnetic field, thereby enhancing the subsequent leaching rate compared to that of raw ore. The results of a laboratory study into the effect of varying roasting times, temperatures and the intensity of the magnetic field are presented and discussed. The work showed that the pretreatment altered the microstructure of the bauxite. The optimal roasting conditions were found to be a 60 min roast at 550 degrees C in a magnetic field of 6T., A sample of diasporic bauxite from China's Henan province was pretreated by roasting in a magnetic field, thereby enhancing the subsequent leaching rate compared to that of raw ore. The results of a laboratory study into the effect of varying roasting times, temperatures and the intensity of the magnetic field are presented and discussed. The work showed that the pretreatment altered the microstructure of the bauxite. The optimal roasting conditions were found to be a 60 min roast at 550 degrees C in a magnetic field of 6T.

食品の微生物制御で重要となる数種の細菌を対象として、17種の香辛料と5種のハーブの抗菌性を試験した。試料にはエタノールで抽出したエキスを用いた。香辛料の抗菌性は全般的にグラム陰性菌よりもグラム陽性菌に対して強かった。とくに、高い耐熱性の芽胞を形成して缶詰のフラットサワー原因菌として問題となる Bacillus stearothermophilns は大部分の香辛料に感受性を示した。なかでも、パプリカはMIC(最小発育限止濃度)が0.005%と最も強い抗菌性を示し、アニス(MIC:0.01%)、メース(MIC:0.02%)がそれに次いだ。これらの抗菌性は基礎培地のpHを弱酸性にしたり、塩分濃度を少し高めることによって強くなり、pH6.0および1.5%NaCl存在下でMICは約1オーダー低下した。しかし、乳酸ナトリウムとの相乗効果はほとんど認められなかった。以上の結果は、寒天希釈法と液体希釈法、接種物として栄養細胞と芽胞、いずれを用いた場合も差はみられなかった。セージは0.1%濃度で Bacillns 属細菌(B. subtilis, B. cereus, B. coagulans)の発育を完全に阻止した。カモミールなどのハーブの抗菌性は比較的低かった。グラム陰性菌について Eseherichia coli と Sainonella はいずれの香辛料でも0.2%濃度で発育阻害はみられず、Vibrio cholerae non-O1がセージ、ホワイトペッパーおよびクローブに感受性を示したのみであった。以上、食品中での耐熱性芽胞形成菌の制御に一部の香辛料が有効である可能性を明らかにした。, The present study was designed to identify spices and herbs that possess antibacterial activity and to apply for control of microorganisms in food. Alcoholic extracts of seventeen spices and five herbs were prepared and examined for growth inhibition of several kinds of food-related bacteria in culture media. Bacillus stearothermophilus, which produces heat-resistant spores, was highly sensitive to most of the spices tested. Both germination of spores and outgrowth of vegetative cells of this organism were inhibited by most of the spices tested. The MICs (minimal inhibitory concentrations) were 0.005% for paprika, 0.01% for anise and 0.02% for mace both on agar and in liquid media. The inhibition of this organism by effective spices was influenced by pH and NaCl concentration of the basal medium. When the pH and NaCl were 6.0 and 1.5%, respectively, the MICs decreased to 10-20%. No synergistic effect of spice and sodium lactate was observed except for mace. At 0.05%, nutmeg, sage, and white pepper perfectly inhibited the growth of this organism. Garlic showed no antibacterial effect and turmeric was also less effective. In general, antibacterial activity of herbs such as chamomile was comparatively low. Against B. coagulans, sage and rosemary inhibited the growth and the MICs were 0.05% and 0.2%, respectively. Both Escherichia coli and Salmonella were not inhibited by 0.2% concentration of all the spices and herbs tested. Sage showed the inhibitory effects against B. subtilis, B. cereus and Staphylococcus aureus. These results suggest that control of the thermophilic bacteria, especially B. stearothermophilus, in canned foods is possible by some spices.

High-alumina fly ash grading 40 wt% Al2O3 is seen as a novel and valuable substitute for bauxite in China, where fly ash is one of the most abundant industrial wastes, but both soda-lime sintering and acid leaching discharge other valuable elements such as Mg and Ca as waste residues containing large amounts of acid or alkali. Carbochlorination has been proposed as an environmentally benign process that can significantly improve the economic value of fly ash. The effects of reaction temperature, time, C content, pellet diameter and Cl2 gas flow rate on the carbochlorination of Mg- and Ca-bearing compounnds in fly ash are investigated and the kinetic mechanisms of the processes identified. The results show that chemical reaction control is dominant in carbochlorination of Mg in the temperature range 800-1 050 degrees C but that carbochlorination of Ca is controlled by the diffusion process. Morphological changes such as the breakage and disappearance of spherical particles showed that the original spherical structure of the fly ash was destroyed by carbochlorination., High-alumina fly ash grading 40 wt% Al2O3 is seen as a novel and valuable substitute for bauxite in China, where fly ash is one of the most abundant industrial wastes, but both soda-lime sintering and acid leaching discharge other valuable elements such as Mg and Ca as waste residues containing large amounts of acid or alkali. Carbochlorination has been proposed as an environmentally benign process that can significantly improve the economic value of fly ash. The effects of reaction temperature, time, C content, pellet diameter and Cl2 gas flow rate on the carbochlorination of Mg- and Ca-bearing compounnds in fly ash are investigated and the kinetic mechanisms of the processes identified. The results show that chemical reaction control is dominant in carbochlorination of Mg in the temperature range 800-1 050 degrees C but that carbochlorination of Ca is controlled by the diffusion process. Morphological changes such as the breakage and disappearance of spherical particles showed that the original spherical structure of the fly ash was destroyed by carbochlorination.

In order to develop a multistage reduction process for ferrotitanium low in O and Al, the effects of Al reductant ratio on the occurrence and distribution of residual Al and O were studied. High-Ti slag grading 88.98% TiO2 and 2.56% Fe2O3 from Panzhihua and ilmenite concentrate grading 41.71% TiO2 and 44.14% Fe2O3 from Jinzhou, China, were used as raw materials to prepare two types of ferrotitanium, one containing 21.22-26.2wt% Ti and the other 49.64-55.42wt% Ti, by aluminothermic reduction with reducing agent ratios of 1.05, 1.0, 0.95, 0.90, 0.85 and 0.80. Al residues were found to be present in the form of Ti3Al and Al2O3 inclusions. Residual O in the lower-Ti ferrotitanium was mainly present in Al2O3 inclusions but in the higher-Ti ferrotitanium was in the form of Ti4Fe2O, TiO and Al2O3 inclusions. The ratio of reducing agent controlled both the content and the state of occurrence of Al and O., In order to develop a multistage reduction process for ferrotitanium low in O and Al, the effects of Al reductant ratio on the occurrence and distribution of residual Al and O were studied. High-Ti slag grading 88.98% TiO2 and 2.56% Fe2O3 from Panzhihua and ilmenite concentrate grading 41.71% TiO2 and 44.14% Fe2O3 from Jinzhou, China, were used as raw materials to prepare two types of ferrotitanium, one containing 21.22-26.2wt% Ti and the other 49.64-55.42wt% Ti, by aluminothermic reduction with reducing agent ratios of 1.05, 1.0, 0.95, 0.90, 0.85 and 0.80. Al residues were found to be present in the form of Ti3Al and Al2O3 inclusions. Residual O in the lower-Ti ferrotitanium was mainly present in Al2O3 inclusions but in the higher-Ti ferrotitanium was in the form of Ti4Fe2O, TiO and Al2O3 inclusions. The ratio of reducing agent controlled both the content and the state of occurrence of Al and O.

To enable use of copper slag and extract the maximum value from the contained copper, an innovative method of reducing moderately diluted slag to smelt copper-containing antibacterial stainless steel is proposed. This work focused on moderate dilution of copper slag using natural gas. The thermodynamics of copper slag dilution and ternary phase diagrams of the slag system were calculated. The effects of blowing time, temperature, matte settling time, and calcium oxide addition were investigated. The optimum reaction conditions were identified to be blowing time of 20 min, reaction temperature of 1 250 degrees C, settling time of 60 min, CaO addition of 4% of mass of slag, natural gas flow rate of 80 ml/min, and outlet pressure of 0.1 MPa. Under these conditions, the Fe3O4 and copper contents of the residue were 7.36% and 0.50%, respectively. (Authors.), To enable use of copper slag and extract the maximum value from the contained copper, an innovative method of reducing moderately diluted slag to smelt copper-containing antibacterial stainless steel is proposed. This work focused on moderate dilution of copper slag using natural gas. The thermodynamics of copper slag dilution and ternary phase diagrams of the slag system were calculated. The effects of blowing time, temperature, matte settling time, and calcium oxide addition were investigated. The optimum reaction conditions were identified to be blowing time of 20 min, reaction temperature of 1 250 degrees C, settling time of 60 min, CaO addition of 4% of mass of slag, natural gas flow rate of 80 ml/min, and outlet pressure of 0.1 MPa. Under these conditions, the Fe3O4 and copper contents of the residue were 7.36% and 0.50%, respectively. (Authors.)

The effects were studied of roasting time and temperature on the S content and digestion performance of high-S bauxite subjected to roasting pretreatment in a rotary kiln. The sulphurisation and roasting mechanisms were also investigated. The results showed that S was removed as a gaseous product and the S content of the bauxite was reduced to below 0. 7% at a roasting temperature of 700 degrees for 30 min. The bauxite product was suitable for use in alumina production and the digestion temperature was reduced from 240 to 220 degrees C., The effects were studied of roasting time and temperature on the S content and digestion performance of high-S bauxite subjected to roasting pretreatment in a rotary kiln. The sulphurisation and roasting mechanisms were also investigated. The results showed that S was removed as a gaseous product and the S content of the bauxite was reduced to below 0. 7% at a roasting temperature of 700 degrees for 30 min. The bauxite product was suitable for use in alumina production and the digestion temperature was reduced from 240 to 220 degrees C.

High-S bauxite was pretreated in muffle, rotary tube and fluidised bed furnaces and the effects of roasting temperature and time on desulphurisation and digestion rate were studied. The results showed that elemental S was removed in the gas phase and that the S content of the roasted ore met the relevant industry standard. Optimum conditions for roasting pretreatment using the muffle or rotary tube furnaces were 750 degrees C for 30 min, for the fluidised bed furnace 800 degrees C for 10 min. The roasted ore produced using the fluidised bed exhibited the best digestion performance, with a digestion rate of 93.7% being achieved at 220 degrees C, a molar ratio of 1.3 and caustic soda concentration of 220 g/l., High-S bauxite was pretreated in muffle, rotary tube and fluidised bed furnaces and the effects of roasting temperature and time on desulphurisation and digestion rate were studied. The results showed that elemental S was removed in the gas phase and that the S content of the roasted ore met the relevant industry standard. Optimum conditions for roasting pretreatment using the muffle or rotary tube furnaces were 750 degrees C for 30 min, for the fluidised bed furnace 800 degrees C for 10 min. The roasted ore produced using the fluidised bed exhibited the best digestion performance, with a digestion rate of 93.7% being achieved at 220 degrees C, a molar ratio of 1.3 and caustic soda concentration of 220 g/l.

A novel methodology is presented for preparing an as-cast Ti-Al-V alloy directly from titanium-rich material through a thermite reduction. The new method is shown to be feasible through a thermodynamics and dynamics analysis. The as-cast Ti-Al-V alloys synthesised from titanium dioxide, rutile, and high-titanium slag were analysed by an X-ray diffractometer, a scanning electron microscope, an inductively coupled plasma emission spectrometer, and an oxygen/nitrogen/hydrogen analyser. The results indicate that the alloy is composed of a Ti-Al-V matrix and Al2O3 inclusions. The Al and V contents in the matrix are close to the mass ratio of Ti-6Al-4V (5.5-6.8 wt.% Al, 3.5-4.5 wt.% V). The Si and Fe in the alloys synthesised from rutile and high-titanium slag can be used as alloying elements in low-cost titanium alloys. The present method is expected to be useful for preparing Ti-Al-V alloys at a low production cost. (Authors.), A novel methodology is presented for preparing an as-cast Ti-Al-V alloy directly from titanium-rich material through a thermite reduction. The new method is shown to be feasible through a thermodynamics and dynamics analysis. The as-cast Ti-Al-V alloys synthesised from titanium dioxide, rutile, and high-titanium slag were analysed by an X-ray diffractometer, a scanning electron microscope, an inductively coupled plasma emission spectrometer, and an oxygen/nitrogen/hydrogen analyser. The results indicate that the alloy is composed of a Ti-Al-V matrix and Al2O3 inclusions. The Al and V contents in the matrix are close to the mass ratio of Ti-6Al-4V (5.5-6.8 wt.% Al, 3.5-4.5 wt.% V). The Si and Fe in the alloys synthesised from rutile and high-titanium slag can be used as alloying elements in low-cost titanium alloys. The present method is expected to be useful for preparing Ti-Al-V alloys at a low production cost. (Authors.)

The kinetics of a magnesium production process - the silicothermic reduction of dolime (CaO.MgO) in porous pellets pre-prepared from mixtures of dolomite (from Dashiqiao, Liaoning province, China), ferrosilicon, fluorite and polyvinyl alcohol binder - were investigated using a non-isothermal thermogravimetric method in flowing argon at temperatures in the range 1 323-1 673 degrees K. The results indicate that the kinetics may be represented by a second-order chemical reaction with an apparent activation energy of 280 kJ/mol. Calcium silicide, which was present in the pellets after the calcination process, was transformed into a liquid alloy above 1 300 degrees K, decreasing the diffusion resistance of the silicon during the reduction. The mass-transfer coefficient for magnesium vapour to argon gas at an argon flow rate of 0.0000556 cu m/s and a temperature range of 1 425-1 650 degrees K was calculated to be 0.11-0.14 m/s., The kinetics of a magnesium production process - the silicothermic reduction of dolime (CaO.MgO) in porous pellets pre-prepared from mixtures of dolomite (from Dashiqiao, Liaoning province, China), ferrosilicon, fluorite and polyvinyl alcohol binder - were investigated using a non-isothermal thermogravimetric method in flowing argon at temperatures in the range 1 323-1 673 degrees K. The results indicate that the kinetics may be represented by a second-order chemical reaction with an apparent activation energy of 280 kJ/mol. Calcium silicide, which was present in the pellets after the calcination process, was transformed into a liquid alloy above 1 300 degrees K, decreasing the diffusion resistance of the silicon during the reduction. The mass-transfer coefficient for magnesium vapour to argon gas at an argon flow rate of 0.0000556 cu m/s and a temperature range of 1 425-1 650 degrees K was calculated to be 0.11-0.14 m/s.

The thermodynamics were investigated of the V-Fe-H2O system at an oxygen partial pressure of 0.5 MPa, an ionic activity factor equivalent to a concentration of 0.1 mol/kg and temperatures of 60, 100, 150 and 200 degrees C. The potential/pH diagrams showed that stable regions for V(3+) VO(2+) and VO2(+) ions were in the region for Fe(3+) and Fe(2+) ions at pH values less than 2. The pH values of stable regions for V(3+) VO(2+), VO2(+), Fe(3+) and Fe(2+) ions became more negative and the redox potentials increased with increasing temperature. The stable regions for vanadium iron spinel and other oxides were significantly less affected. The calculations showed that V could be extracted using oxygen pressure acid leaching, but Fe could not be separated in a one-step leaching process and purification of the leachate is required to obtain V products. Experimental results showed that V and Fe leaching rates of 96.87% and 89.25% could be obtained at 140 degrees C, oxygen partial pressure of 0.5 MPa, particle size of 0.055-0.075 mm, liquid solid ratio of 15:1 v/w, leaching time of 120 minutes, stirring speed of 500 r/minute and initial acid concentration of 200 g/l. Good agreement was obtained between the thermodynamic calculations and the experimental results., The thermodynamics were investigated of the V-Fe-H2O system at an oxygen partial pressure of 0.5 MPa, an ionic activity factor equivalent to a concentration of 0.1 mol/kg and temperatures of 60, 100, 150 and 200 degrees C. The potential/pH diagrams showed that stable regions for V(3+) VO(2+) and VO2(+) ions were in the region for Fe(3+) and Fe(2+) ions at pH values less than 2. The pH values of stable regions for V(3+) VO(2+), VO2(+), Fe(3+) and Fe(2+) ions became more negative and the redox potentials increased with increasing temperature. The stable regions for vanadium iron spinel and other oxides were significantly less affected. The calculations showed that V could be extracted using oxygen pressure acid leaching, but Fe could not be separated in a one-step leaching process and purification of the leachate is required to obtain V products. Experimental results showed that V and Fe leaching rates of 96.87% and 89.25% could be obtained at 140 degrees C, oxygen partial pressure of 0.5 MPa, particle size of 0.055-0.075 mm, liquid solid ratio of 15:1 v/w, leaching time of 120 minutes, stirring speed of 500 r/minute and initial acid concentration of 200 g/l. Good agreement was obtained between the thermodynamic calculations and the experimental results.

The thermodynamics of the leaching of converter slag were investigated based on a study of the phi-pH diagram of the V-Ti-H2O system at an oxygen partial pressure of 0.5 MPa, ionic mass concentration of 0.1 mol/kg and temperatures in the range 60-200 degrees C. At pH values less than 2 stable V(3+), VO(2+) and VO2(+) regions exist in the stable region for TiO2, and the pH values of stable Ti and V regions decrease and the redox potentials become more positive with increasing temperature. The thermodynamic data indicate that V and Ti may be separated using a one- step leaching process. Experiments were carried out on the pressure acid leaching of a slag from Panzhihua, China, containing 8.07% V, 10.71% TiO2, 36.33% total Fe, 15.43% SiO2, 7.72% MnO, 5.47% MgO, 3.23% Cr2O3, 2.58% Al2O3 and 2.38% CaO. V and Ti leaching rates of 96.87% and 8.76%, respectively, were obtained at a temperature of 140 degrees C, reaction time 120 min, oxygen partial pressure of 0.5MPa, particle size of 0.055-0. 075 mm, liquid/solid ratio of 15:1, and initial acid concentration of 200 g/l and stirring at 500 r/min. The experimental results were in agreement with the thermodynamic calculations., The thermodynamics of the leaching of converter slag were investigated based on a study of the phi-pH diagram of the V-Ti-H2O system at an oxygen partial pressure of 0.5 MPa, ionic mass concentration of 0.1 mol/kg and temperatures in the range 60-200 degrees C. At pH values less than 2 stable V(3+), VO(2+) and VO2(+) regions exist in the stable region for TiO2, and the pH values of stable Ti and V regions decrease and the redox potentials become more positive with increasing temperature. The thermodynamic data indicate that V and Ti may be separated using a one- step leaching process. Experiments were carried out on the pressure acid leaching of a slag from Panzhihua, China, containing 8.07% V, 10.71% TiO2, 36.33% total Fe, 15.43% SiO2, 7.72% MnO, 5.47% MgO, 3.23% Cr2O3, 2.58% Al2O3 and 2.38% CaO. V and Ti leaching rates of 96.87% and 8.76%, respectively, were obtained at a temperature of 140 degrees C, reaction time 120 min, oxygen partial pressure of 0.5MPa, particle size of 0.055-0. 075 mm, liquid/solid ratio of 15:1, and initial acid concentration of 200 g/l and stirring at 500 r/min. The experimental results were in agreement with the thermodynamic calculations.

A laboratory study was carried out into the direct oxygen pressure leaching of a bulk flotation concentrate to extract Zn and elemental S. The major minerals present in the concentrate were sphalerite, marmatite and quartz, together with other minerals including Pb and Ti. Lignosulphate was used as a leaching additive to prevent encapsulation of the concentrate particles with S. Optimum parameters were determined to be a concentrate particle size of less than 44 micrometres, leaching temperature of 150 degrees C, leaching time 2 h, oxygen partial pressure 1 MPa, initial sulphuric acid concentration 15%, lignosulphate addition of 1% and solid/liquid ratio of 1:4. Zn leaching rates of up to 95% and S reduction rates of up to 90% were achieved., A laboratory study was carried out into the direct oxygen pressure leaching of a bulk flotation concentrate to extract Zn and elemental S. The major minerals present in the concentrate were sphalerite, marmatite and quartz, together with other minerals including Pb and Ti. Lignosulphate was used as a leaching additive to prevent encapsulation of the concentrate particles with S. Optimum parameters were determined to be a concentrate particle size of less than 44 micrometres, leaching temperature of 150 degrees C, leaching time 2 h, oxygen partial pressure 1 MPa, initial sulphuric acid concentration 15%, lignosulphate addition of 1% and solid/liquid ratio of 1:4. Zn leaching rates of up to 95% and S reduction rates of up to 90% were achieved.

Investigations were carried out into the characteristics of the rock surrounding the roadway to be driven along the gob during the mining of a fully mechanised caving face at the Fucun coal mine in China in order to design the optimum support method. A support system consisting of a combination of rock bolting and mesh ladder and rock bolting and rope girder was developed based on the pressure and deformation of the roadway. The method selected resulted in little deformation of the roadway and ensured safe production during stoping., Investigations were carried out into the characteristics of the rock surrounding the roadway to be driven along the gob during the mining of a fully mechanised caving face at the Fucun coal mine in China in order to design the optimum support method. A support system consisting of a combination of rock bolting and mesh ladder and rock bolting and rope girder was developed based on the pressure and deformation of the roadway. The method selected resulted in little deformation of the roadway and ensured safe production during stoping.

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