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Comprehensive utilization of stainless-steel slag (SSS) is restrained due to the risk of Cr6+ leaching. Based on the studying the microstructure of synthetic slag (SS) containing Cr2O3 with XRD, SEM-EDS, and Image pro, the effect of binary basicity on the chromium occurrence in SSS was investigated. The results indicated that the binary basicity had a significant impact on the properties of spinel crystals. There was a positive correlation between the calcium content in spinel crystals and the SS basicity. The size of spinel crystals varied from large to small and the precipitation occurrence changed with the basicity increase. Furthermore, the chromium occurrences changed with the basicity. The chromium was produced in spinel crystals at lower basicity, but as the basicity increased to 3.0, the chromium precipitated as calcium chromate. In view of the relationship between the chromium leaching behavior and its occurrence, increasing basicity raised the Cr6+ leaching.

In order to study the effect of soil salinity on fertilizer nitrogen transformation, a laboratory culture experiment was conducted with six salinity levels (soil salt content was: 0.17%, 0.99%, 1.64%, 2.32%, 2.91%, 3.79%, respectively) and 6 fertilizer treatments (no fertilizer (CK), low (UPL), medium (UPM) and high three urea phosphate doses (150 kg N/hm2, 300 kg N/hm2 and 600 kg N/hm2), low (URL) and high urea doses (URH) (300 kg N/hm2 and 789 kg N/hm2)). With the increase of soil salinity, the average ammonia volatilization loss rate increased from 1.07% to 9.17%. The average of cumulative ammonia volatilization under different fertilization treatments basically followed the order: URH > URL > UPH > UPM > UPL > CK. With the increase of soil salinity, the average net nitrated nitrogen under different fertilizer treatment was 52.66, 43.06, 68.86, 43.18, 31.10, 22.66 mg/kg in order. Soil inorganic nitrogen transformation increased with the increase of fertilizer application. The net nitrated nitrogen and inorganic nitrogen transformation of soils with different salinity under UPM treatment were higher than those under URL treatment. [ABSTRACT FROM AUTHOR]

Hybrid improper ferroelectricity (HIF) has been proposed as a candidate approach to create room- temperature multiferroic materials with an intrinsic electric-field controlled magnetism effect, and HIFs in bi-layered Ruddlesden-Popper Ca3-xSrxTi2O7 ceramics have been confirmed in the present work. The ferroelectric hysteresis loops are observed in these ceramics at room temperature, and the polar orthorhombic structures with oxygen octahedral rotation and tilt modes have been confirmed by room-temperature X-ray powder diffraction. The amplitudes of oxygen octahedral rotation and tilt modes decrease with the increasing x value, which in turn leads to the decrease of remnant polarization in these ceramics. A first-order phase transition has been evidenced by the differential scanning calorimetry measurement, and the temperature of phase transition decreases linearly with the increasing content of strontium cations. It is found that the amplitude of oxygen octahedral distortion is the dominating factor that affects ferroelectric polarization in partial-ordered bi-layered Ca3Ti2O7-based ceramics. [ABSTRACT FROM AUTHOR]

OBJECTIVE: To investigate the efficacies and mechanisms of combination therapy with interleukin-15 (IL-15) and metformin (Met) on suppressing pancreatic cell proliferation and protecting Panc02-bearing mice. MATERIALS AND METHODS: MTT assays were applied to assess the inhibitory effects of IL-15 combined Met or Met and IL-15 alone on proliferation of normal HPDE6-C7 and Panc02 cells. After tumor grew up to 150 mm3, the Panc02-bearing xenograft model mice were randomly divided into saline group, IL-15 and Met alone group and combined treatment group (n=8) with the administration of each agent every other day for three weeks, and survival rates were recorded. The changes in tumor size, expression levels of the apoptosis, autophagy as well as Akt/mTOR/STAT3-related factors in tumor tissues were all measured. RESULTS: MTT assays demonstrated significantly inhibiting efficacy of combination therapy with IL-15 and Met on Panc02 cell proliferation compared to other groups (all p<0.05) with combination index<1 showing evident synergistic effect. Moreover, the apoptosis rate of Panc02 cell under combined treatment were 95.5±3.2% and significantly higher than those of others (all p<0.01). In addition, combined administration remarkably inhibited the growth of pancreatic carcinoma, and improved survival rate of Panc02-bearing model with less body weight loss. Furthermore, combined treatment significantly downregulated anti-apoptotic proteins as well as Akt/mTOR/STAT3 signaling pathway and upregulated autophagy related factors, respectively, compared with those of monotherapy groups in both Panc02 cells and tumor tissues. CONCLUSIONS: Combined treatment of IL-15 with Met showed synergistic anti-tumor efficacies on Panc02 cells attributing to promotion on apoptosis, autophagy and inhibition on Akt/mTOR/STAT3 signaling-transduction in Panc02-bearing model mice. [ABSTRACT FROM AUTHOR]

Studies on BN alternants, wherein the carbons in an alternant hydrocarbon are replaced by B and N, reveal that these species are stable and help understand the formation of carbon tubes. These species are soluble with respect to eigensolutions for the respective alternant hydrocarbons, as revealed by the extended Huckel models for the alternants. The opening of band gaps and HOMO-LUMO gaps for polymers and clusters, respectively, of these alternants can be explained by the varying electronegativities of B and N.