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In this study, a clean oxidation process for the treatment of wastewater containing hydroxypropyl guar gum (HPGG) and other polymers under a high pH range was designed. For that, 5-sulfosalicylic acid (L)-Co(II) complex supported on bentonite (B) (B@Co(II)L) was prepared for treatment of wastewater by hydrogen peroxide ($\mathrm{H}_{2}\mathrm{O}_{2}$). The morphology and pore structure of B@Co(II)L was first characterized by scanning electron microscopy (SEM), powder X-ray diffraction (XRD), Fourier infrared spectrometer (FT-IR), and $\mathrm{N}_{2}$ adsorption–desorption isotherms, after which the catalytic performance was investigated for the treatment of polymer wastewater. Results show that B@Co(II)L performed high catalytic performance in a wide range of 7.0 to 13.0. The viscosity of the HPGG can be decreased effectively from 22 to 2.5 mm$^{2}$/s under the optimal conditions of 45 °C, pH 10.0, 10% $\mathrm{H}_{2}\mathrm{O}_{2}$ (mass ratio to HPGG), and 10% B@Co(II)L (mass ratio to $\mathrm{H}_{2}\mathrm{O}_{2}$), and the removal rate for chemical oxygen demand (COD) of HPGG, CMC, and PAM reached to 95.9%, 94.8%, and 93.7%, respectively, within 240 min. Most of all, by applying the catalyst in the oilfield, it was found that the catalyst has high performance and the removal rate for COD of oilfield wastewater, fracturing fluids, and drilling fluid can be achieved by 92.1%, 94.2%, and 90.7%, respectively.

Polycrystalline Bi4CoxFe2xTi3−3xO12 (BC2FT) ceramics (0 ≤ x ≤ 0.4) were synthesized by conventional solid state reaction and their dielectric, multiferroic and magnetodielectric (MD) properties have been investigated. The XRD data results reveals that all samples possess a layered perovskite structure belonging to the n = 3 members of the Aurivillius family and a secondary phase of Bi5Ti3FeO15 could be observed at higher concentrations. The average grain size is found to decrease with the increase of x. Permittivity values decrease with the content of Co and Fe increasing (0.1 ≤ x ≤ 0.4). BC2FT ceramics exhibit ferroelectric and weak ferromagnetic properties at room temperature. Room-temperature magnetodielectric (MD) and magnetodielectricloss effect were observed in all samples, resulting from the contributions of the magnetostriction effect. Furthermore, with the dopant content of Co and Fe increasing, the negative peaks shift to a lower frequency and the positive peak get the largest room-temperature MD response of 0.649% at 97.88 Hz with x = 0.4. [ABSTRACT FROM AUTHOR]

An ultralow interfacial tension (IFT) oil displacement agent, which was a surfactant combinational system (HCS) with good salt and heat resistance, was synthesized using amphoteric betaine (AMS)/anionic sulfonate (AKS)/nonionic alkyl amide (NIS). The interface tensiometer was used to test the IFT. The results showed that the oil–water IFT could be as low as 10−4mN/m when the salinity is 10,000∼50,000 mg/L, the concentration is 1∼5 g/L, and the temperature is 40∼80°C. The surfactant system has good emulsification stability. The displacement simulation experiments demonstrated that the increment of the recovery ratio can be up to 14.1%. The surfactant system could meet the demands of site operation. [ABSTRACT FROM PUBLISHER]

Based on aqueous solution polymerisation, a hydrophobic association fracturing fluid thickener (HAT-1) was synthesised by using acrylamide (AM), acrylic acid (AA), 2-acrylamide-2-methylpropanesulphonic acid (AMPS) and N-dodecyl acrylamide (NDAM) as raw materials. The factors that influenced synthetic process of HAT-1 were investigated and the optimum synthetic conditions were obtained as follows: reaction temperature - 70°C, polymerisation time - 4 h, total monomer amount - 25%, initiator amount - 0.03% (compared to total monomer amount), pH value of the reaction system - 8, monomer molar ratio of AM, AA, AMPS, N-DAM - 80:15:4:1. Laboratory evaluation shows that HAT-1 fracturing fluid system has better performances on heat resistance, shear resistance, sand-carrying capability and gel-breaking property. Residue content of HAT-1 broken fluid is lower than regular fracturing fluid, could satisfy the fracturing operation requirement for the reservoirs below 90°C. [ABSTRACT FROM AUTHOR]

A bifunctional catalyst comprising CuCl 2 /Al 2 O 3 and nitrogen-doped carbon was developed for an efficient one-pot ethylene oxychlorination process to produce vinyl chloride monomer (VCM) up to 76 % yield at 250 °C and under ambient pressure, which is higher than the conventional industrial two-step process (≈50 %) in a single pass. In the second bed, active sites containing N-functional groups on the metal-free N-doped carbon catalyzed both ethylene oxychlorination and ethylene dichloride (EDC) dehydrochlorination under the mild conditions. Benefitting from the bifunctionality of the N-doped carbon, VCM formation was intensified by the surface Cl*-looping of EDC dehydrochlorination and ethylene oxychlorination. Both reactions were enhanced by in situ consumption of surface Cl* by oxychlorination, in which Cl* was generated by EDC dehydrochlorination. This work offers a promising alternative pathway to VCM production via ethylene oxychlorination at mild conditions through a single pass reactor., (© 2020 The Authors. Published by Wiley-VCH GmbH.)

Objective: To explore the effect of acrylonitrile exposure on the expression of Bcl-2 and Bax in mice spermatogenic cells., Methods: Based on body weight, 250 SPF Kunming adult male mice were randomly divided into five groups: negative control group (normal saline 0.01ml/g), three AN exposure groups (intraperitoneal injection of 1.25, 2.50 or 5.00 mg/kg of AN daily for 5 days, respectively) and positive control group (intraperitoneal injection of cyclophosphamide 40mg/kg). Mice were killed in the 7th, 14th, 21st, 28th and 35th day after the first exposure by cervical dislocation. Immunohistochemical method (SABC) was used to detect the expression of Bcl-2 and Bax protein in spermatogenic cells., Results: The average optical density values of Bcl-2 at five time points of the AN 2.50 mg/kg group and the 21th day point of the AN 1.25mg/kg group were significantly lower than the negative control group (P < 0.05). Except the 21st day point of the AN 1.25 mg/kg group, the mean optical density values of Bax in all time points of AN exposure groups were significantly higher than the negative control group (P < 0.05). The decreased expression of Bcl-2 protein was most distinct in AN 2.50mg/kg group and the positive control group at all time points. The expression of Bax protein was significantly increased in all groups at the 14th day point., Conclusion: The expression of Bcl-2 protein could be weakened in spermatogenic cells induced by AN, especially in the AN 2.50 mg/kg group; while the expression of Bax was enhanced, and the amplitude of change in the 14th day point was more obvious.

Objective: To understand the status and associated factors of overweight and obesity of rural children under 7 year-old in Gansu province., Methods: A total of 9390 rural children under 7 year-old and their mothers in 4 counties in Gansu province were selected by stratified random cluster sampling method and screened for overweight or obesity by BMI. All data were input by using a double entry method with EPI data 3.0 software and analyzed statistically by Excel/SPSS 10.0 software., Results: The detection rate of overweight in rural children under 7 in Gansu province was 8.2% (male 8.7%, female 7.9%), the detection rate of obesity was 6.1% (male 6.4%, female 5.8%). The independent risk factors for overweight and obesity were birth weight > or = 4000 g and living in scattered lifestyle., Conclusion: The risks of overweight and obesity in rural children are rather high, more attention should be paid to children aged from 9 month to 2 years. Reducing the rate of birth weight > or = 4000 g and scattered lifestyle in children can make some contribution to the prevention of obesity and overweight.