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As a new type of biologically compatible material, TiO2 NPs are widely used in the industry as additives, drug carriers, and components of skin care products. Due to their wide use, residual TiO2 NPs in the environment are a safety concern that has attracted extensive attention. In this study, the ovarian cell line BmN of the model organism Bombyx mori was used to reveal the damaging effects of TiO2 NPs exposure. The results demonstrated that TiO2 NPs exhibited a dose-dependent effect on the relative cell viability, with significant toxic effects being observed above 20 mg/L. Oxidative damage analysis showed that ROS accumulated significantly in BmN cells after exposure to TiO2 NPs (P ≤ 0.05) and induced DNA damage. Further analysis revealed that the transcriptional levels of key superoxide dismutase genes (SOD) decreased significantly, while the transcriptions of key genes of the MAPK/NF-κB signaling pathway (P38, MEK, ERK and REL) and the downstream inflammatory factor genes (IL6 and TNFSF5) were all significantly up-regulated (P ≤ 0.05). Overall, our results indicate that exposure to TiO2 NPs leads to reduced transcription of antioxidant genes, accumulation of peroxides, and inflammation. These findings provide valuable data for the safety evaluation of environmental residues of TiO2 NPs.

A zwitterionic surfactant, hexadecyl hydroxypropyl sulfo betaine, was examined for its ability to stabilize supercritical CO2 (SC-CO2) foam, with the goal of improving the oil recovery from mature ...

As a new type of biologically compatible material, TiO

Underground cross-linking profile control and water shutoff and deep fluid flow to chemical agent system are usually composed of main agent, cross-linking agent and additives. The cost of cross-linking agent and additives generally accounts for 30–50% of the total cost of the system. Many inorganic salt ions are widely used as cross-linking agent or additives. In this paper, using Ca2+ and Mg2+ scale forming ion source in CaCl2 water type oilfield high salinity formation water (as water injection) as crosslinking agent, cross-linking of original inorganic microgel is carried out to reduce the cost of steering agent. The formation of nano microscale inorganic microgel with density similar to that of environmental water source can be formed by cross-linking of the steering agent with scale forming ions in formation water. The microgel can be dispersed or suspended in water, and gradually adsorbed on the rock skeleton of the dominant channel such as hole or crack to form a micro gel coating in order to narrow the flow dominant channel and form resistance to flow. The passage of plugging does not die, achieving the purpose of adjusting the dominant channel, expanding the volume and improving the efficiency of water flooding. At the same time, the particle size of the micro gel can prevent it from entering the low permeability matrix to contaminate the oil layer. The diversion agent has the characteristics of rapid dissolution, temperature resistance, salt resistance, environmental protection, long-term effectiveness and no construction risk. Field tests of deep profile control and flooding have been carried out in reservoirs with different temperature and salinity at home and abroad. After profile control diversion in test blocks or well groups, the effect of improving water flooding is good. The average increase of water injection pressure is 2–3 MPa, and the effective rate of increasing oil production and precipitation in oil wells is more than 80%, and the validity period is less than one year up.

High temperature-resistant polymer (HTP) was synthesized by in-situ cross-linking of interpenetrating reaction using H-2 monomer containing amide bond and H-1 molecule containing hydroxyl as raw materials. IR spectra result showed that there were characteristic functional groups of H-1 and H-2 cross bond at the same time, that was to say that H-1 cross-linking reaction and H-2 polymerization could simultaneously take place. The interpenetrating cross-linking structure, extension properties at room temperature and long-term heat resistance properties of the material were tested. The experiment results showed that in the whole range of observations, HTP material cross-links and interpenetrates uniformly. The SEM pictures confirmed the interpenetration structure of HTP material. After cross-linking and interpenetration, the scale of HTP structure became smaller than before. This material had tensile resistance, dispersion stability in water, volume expansion, and could reach the maximum swelling ratio of 1.69 within 1.5 h at room temperature. At 90 °C, 120 °C and 140 °C, after soaking 130 days in formation water, HTP volume reduction rate was 1.57%, 3.24% and 6.82%, respectively.

Using Illumina next-generation sequencing (NGS), the complete mitochondrial genome of the Psenopsis anomala was sequenced in the present study. The mitochondrial genome of P. anomala is 16,528 bp long and consists of 13 protein-coding genes, 2 rRNA genes, 22 tRNA genes, and a control region. The structure about gene order and composition of P. anomala mitochondrial genome is similar to those of most other vertebrates. The nucleotide compositions of the light strand in descending order is 29.18% of T, 27.97% of G, 27.06% of A, and 15.79% of C. With the exception of the NADH dehydrogenase subunit 6 (ND6) and eight tRNA genes, other mitochondrial genes are encoded on the heavy strand. The phylogenetic analysis by maximum-likelihood (ML) method shown that the Psenopsis anomala was closer to Peprilus triacanthus in the phylogenetic relationship.

In this paper, we use fuzzy comprehensive evaluation method that based on the AHP to surveillance and evaluation in acceptance stage of E-government, and builds some related hierarchical indicators through actual and needs, sets up the factor sets, the evaluation sets, subjection functions and the weighting sets to implement surveillance and evaluation. The choosing big or small algorithm and the maximal subjection degree of the evaluation result are improved in fuzzy comprehensive evaluation. Example in this paper indicates that the researched method is feasible and effective.