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The substitution of iron ore tailing powders(IP) for fly ash as mineral admixtures was studied in the development of engineered cementitious composites(ECC). The focus was placed on the effect of IP content on the tensile properties and compressive strength of ECC. The mechanical properties of ECC with IP were also compared with those of traditional ECC with fly ash. Experimental results show that it is feasible to use IP as mineral admixtures to produce high-ductile ECC. ECC with IP exhibits a lower strength performance but a higher ductility under tensile load than ECC with fly ash at the same addition of mineral admixtures. ECC with an IP/cement mass ratio of 1. 2-2. 2 shows a 28-d compressive strength of 36. 7-54. 2 MPa,which meets the compressive strength requirement of normal concrete structures,and a 28-d tensile ductility of 3. 4%-4. 3%. The amount of iron ore tailings in those mixtures accounts for 66. 6%-77. 0% of the total solid matrix ingredients of ECC.

On the purpose of improving the utilization level of mine solid wastes and reducing the cost of backfill mining, this article reports an experimental study on preparing cementitious materials for backfilling by using water-granulated nickel slag. Mechanical and chemical activation methods were adopted to improve the cementitious activity of the slag. Taking the strength of backfill bodies as evaluation standards, the hydration activity and cementitious performance of the slag were investigated by changing the grinding fineness and activated agents, and the chemical activation mechanism was analyzed. The results indicate that the cementing agent prepared from the slag (occupying 85% of the total raw materials) can be used to replace cement and meet the production requirements of back-filling materials.

The article discusses a study which investigates the use of antipsychotic polypharmacy (APP) medication in China for the treatment of patients suffering from schizophrenia and its association with factors including quality of life and treatment satisfaction. Topics covered include the use of survey techniques to collect data, the use of the computer software the Statistical Package for the Social Sciences to evaluate the acquired data, and a detailed analysis of the results.

Objective To systematically evaluate the efficacy of clozapine combined with other antipsychotic drugs in the treatment of refractory schizophrenia. Methods We searched Medline, EMBASE, and China Biology Medicine databases in both English and Chinese for randomized controlled trials, quasi-randomization controlled trials, and clinical controlled trials concerning the combinations of clozapine with other antipsychotic drugs for refractory schizophrenia. Quality assessment and data extraction were conducted with the Cochrane collaboration's RevMan 5.3 software. Results Totally 47 trials met the inclusion criteria, in which clozapine was combined with risperidone, aripiprazole, sulpiride, ziprasidone, modified electroconvulsive therapy, valproate, or lithium carbonate, respectively. Analysis showed that most combination strategies were superior to clozapoine alone (P<0.05), except for the combination with lithium carbonate(8 weeks: RR=1.27, 95%CI=0.82-1.97,P=0.28; 12 weeks: RR=1.53, 95% CI=0.45-5.13, P=0.49). Conclusion Reasonable combination of clozapine with other drugs may improve the therapeutic effectiveness and reduce adverse reactions and thus can be effectively used for treating refractory schizophrenia.