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Liquid crystalline polyarylates (LCPs) have excellent thermal stability and mechanical properties, widely used in cutting-edge fields such as aerospace and electronics industries, but the existing LCPs still face the processing problems caused by high melting point (tm >350 °C). Liquid crystal polyarylate thermosets (LCTs) with excellent overall performance are obtained using the reactive end-group phenynyl to encapsulate the main chain of LCPs, effectively regulating the molecular weight and lowering the melting point of the polymers without destroying the liquid crystallinity. The thermal properties of LCTs can be further regulated by modulating the main chain structure. LCTs consisting of p-hydroxybenzoic acid (HBA), terephthalic acid (TA), hydroquinone (HQ), 4,4'-dihydroxybenzophenone (DHBP) and 2, 6-naphthalene dicarboxylic acid (NDA) were synthesized by one-pot melt polycondensation reaction. A series of LCTs were synthesized by adjusting the ratio of HQ to DHBP to further study the relationship between ketone carbonyl groups and LCTs. The results show that the prepared LCTs have high thermal stability (td,5% > 470 °C), typical nematic schlieren textures and oriented microfiber morphology. The addition of ketone carbonyl groups affected the regularity of molecular chain and the proportion of soft and hard segments. With the increase of ketone carbonyl groups content, the glass transition temperature of LCTs decreased. [ABSTRACT FROM AUTHOR]

Copyright of Wool Textile Journal is the property of National Wool Textile Science & Technology Information Center and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Hydroquinone(HQ) was mainly used in the industrial field as a stabilizing agent and antioxygen. The residue of hydroquinone in industrial wastewater was seriously harmful to human body and environment. Therefore, it is of great significance to establish a simple and accurate method for the detection of hydroquinone for food safety and environmental monitoring. In this paper, a nano-zinc oxide-high purity graphite/glass carbon (ZnO-C/GC) composite electrochemical sensor was prepared. The experimental materials were simple and low cost. The structural characteristics, surface characteristics and conductivity of nano-ZnO-C composites material were analyzed by atomic force microscope (AFM), field emission scanning electron microscope (SEM), X-ray diffraction (XRD) and electrochemical AC impedance (EIS). Hydroquinone by cyclic voltammetry (CV) was used to realize the detection of hydroquinone by nano-ZnO-C/GC composite electrochemical sensor. The electrocatalytic mechanism of hydroquinone was explored. The electrochemical sensor has good stability and accuracy for the detection of hydroquinone, a wide linear range, and a detection limit of 1. 0 × 10-8 mol/L. [ABSTRACT FROM AUTHOR]

A method for the determination of the migration of 4, 4'-difluorobenzophenone and hydroquinone in PEEK food contact materials by ultra performance liquid chromatography was established. The samples were soaked in six food simulants. Water, 4% acetic acid, 10% ethanol and 20% ethanol food simulants were directly filtered and injected. The 50% ethanol and 95% ethanol food simulants were concentrated by rotary evaporation, dissolved in water and diluted, and the solution was filtered and injected. The separation was achieved within 7 min by C18 column and acetonitrile-water mobile phase gradient elution. The mass concentration of 4,4'-difluorobenzophenone in six food simulants is linear with the peak area in range of 0.025~0.500 mg/L, and the lower limit of quantification is 0.012~0.020 mg/kg. The mass concentration of hydroquinone has a linear relationship with its peak area in range of 0.1~2.0 mg/L, and the lower limit of quantification was in range of 0.050~0.072 mg/kg. The recoveries at three concentration levels were in the range of 92.5%~109%. The relative standard deviations (RSDs, n=6) were in range of 3.0%~7.6%. The method has been applied to the determination of the migration of 4,4'-difluorobenzophenone and hydroquinone in PEEK plastics for food contact. [ABSTRACT FROM AUTHOR]

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[Objectives] The anti-PRV effect of the drug mifepristone and its synergistic effect with another anti-PRV drug, hydroquinone were investigated to lay the foundation for the research and clinical application of anti-PRV drugs. [Methods] The effect of mifepristone and its combination with hydroquinone on PRV replication in vitro and the stage of action that produced the effect were examined by Western blot and qPCR, and its antiviral effect and synergistic effect with hydroquinone combination were further confirmed by mouse attack protection test. [Results]The antiviral effect of mifepristone at 15 μmol·L-1 increased with increasing drug concentration and occurred at an early stage of PRV replication. The results of in vitro and in vivo tests showed that mifepristone (5 μmol·L-1 in vivo, 40 mg·kg-1 in vitro)alone or in combination with hydroquinone(5 μmol·L-1 in vivo,50 mg·kg-1 in vitro)had antiviral effects and synergistic antiviral effects with hydroquinone. It also reduced the damage to the liver caused by hydroquinone. [Conclusions]Mifepristone had an antiviral effect in the early stage of virus replication, and the combination with hydroquinone had a better antiviral effect. At the same time, it could reduce the damage of hydroquinone to the liver and make up for the efficacy of mifepristone. [ABSTRACT FROM AUTHOR]

Due to the deep reservoir, high temperature and high salt storage conditions in Tahe oilfield, common polyproacrylamide is easy to aging and dehydrate at high temperature, which makes the sealing effect worse. In view of this, it is urgent to develop a gel plugging agent with good aging stability, high strength and good plugging performance under high temperature and high salinity conditions. In this paper, The use of low-cost industrial humic acid as strengthening agent and stabilizer, temperature and salt resistance containing sulfonic acid group polyacrylamide as the main agent, Hexamethylenetetramine, hydroquinone as delayed cross-linking agent, the preparation of humic acid - organic gel, gelling time, gelling strength and high temperature aging stability as the basis to optimize the optimal formula, The gel plugging effect was evaluated by the breakthrough pressure after gel curing of sand-filled tube. The results showed that the optimal formula was 2% humic acid + 0.6% Hexamethylenetetramine + 0.6% hydroquinone +0.5%SV-2, 0.8%SV-5, at 130℃, gelatinizing time 4h, gelatinizing strength 16Pa, dehydration less than 10% within 30 days. After 35mL gel-base solution was injected into the single-tube sand-filled tube, the breakthrough pressure of the system reached 0.86 MPa after curing. After the breakthrough, the system still had 0.12MPa pressure after four times of water scouring of the gel-base solution, indicating that the gel had good plugging effect and good wall adhesion. [ABSTRACT FROM AUTHOR]

The potassium ferrate and powdered activated carbon is used to treat slightly polluted phenol raw water, the effect of dosage of powdered activated carbon, dosing sequence of potassium ferrate and powdered activated carbon, dosage of potassium ferrate, raw water pH, reaction temperature, tirting speeds and reaction time on the removal rate of phenol was studied, and the generated maleic acid and oxalic acid were selected as water quality safety indexes. The results showed that the best treatment conditions for phenol raw water are to add potassium ferrate ( mass ratio to phenol is 25: 1), then add 4. 0 mg/L powdered activated carbon, when the pH of raw water is 8, the temperature is 30 "C, the stirring speed is 180 r/ min, and the reaction time is 40 min. After treatment, the phenol removal rate can reach 60. 8 %, and the residual phenol concentration in the water can meet the hygienic standard of drinking water ( GB 5749-2006). At this time, maleic acid and oxalic acid account for more than 50%, while hydroquinone, a toxic intermediate, accounts for only about 1. 4% and p-benzoquinone for only about 3. 3 % . It can be seen that the combined treatment of slightly polluted phenol raw water by potassium ferrate and powdered activated carbon is not only efficient, but also has high water quality safety. [ABSTRACT FROM AUTHOR]

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In order to effectively slow down the oxidation of S(IV) during the absorption and desorption o£ S02 by organic amines, the effects of hydroquinone (HQ), resorcinol (RE), catechol (CT) and catechol (PR) on the desulfurization and antioxidant properties of 1 -(2-hydroxyethyl) piperazine(HEP) and NyNr-bis (2・hydroxyethyl) piperazine (BHEP) blend amine were studied・ The results showed that the conversion of S(IV) to S(VI) was inhibited by phenolic compounds, in which the antioxidant properties of HQ and PR were better, the RE was poor・ The absorption capacities and desorption rate of blend amine were increased in the presences of HQ, CT and RE, but the absorption capacity is slighdy increased and the desorption rate is significantly decreased in the presence of PR・ Comprehensive comparison, HQ could be considered as an excellent inhibitor on the oxidation reaction o£ sulfite in organic amine desulfurization process. [ABSTRACT FROM AUTHOR]

Copyright of China Surfactant Detergent & Cosmetics (1001-1803) is the property of China Surfactant Detergent & Cosmetics Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to solve the problems of poor stability, low strength, prominent compatibility with cement and so on, a suspension stabilizer (Point-XF) was prepared by using ammonium acrylamide(AM), ammonium persulfate(APS), acrylic acid(AA), thio-glycolic acid(TGA) and potassium hydrogen tartrate (KHT) under certain reaction conditions. Ethylenediamine tetraacetic acid (ED-TA), triethanolamine (TEOA), p-toluenesulfonic acid (PTSA) and hydroquinone (HQ) were used to prepare a complexation enhancer (Point-ZQ) under certain reaction conditions. Then, Point-XF, Point-ZQ, aluminumsulfate[AI2(SO4)3], hydroxymethyl cellulose (HMO and oxalic acid were used to prepare an alkali free liquid accelerator (Point-SN3) by the best process determined by orthogonal test. The test results show that Point-SN3 can not only effectively promote cement hydration, shorten setting time and improve early strength, but also has high stability and good adaptability with a variety of cements. [ABSTRACT FROM AUTHOR]

Copyright of China Brewing is the property of China Brewing Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of New Building Materials / Xinxing Jianzhu Cailiao is the property of New Building Materials Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Food Research & Development is the property of Food Research & Development Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Food Research & Development is the property of Food Research & Development Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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Copyright of Journal of Food Safety & Quality is the property of Journal of Food Safety & Quality Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

α-arbutin has important applications in cosmetics and medicine. However, the extraction yield from plant tissues is relatively low, which restricts its application value. In this study, we investigated the synthesis of α-arbutin using maltodextrin as the donor and hydroquinone as the acceptor, using a cyclodextrin glucosyltransferase (CGTase) from Anaerobranca gottschalkii . We performed site-saturated and site-directed mutagenesis on Ag CGTase. The activity of the variant Ag CGTase-F235G-N166H was 3.48 times higher than that of the wild type. Moreover, we achieved a conversion rate of 63% by optimizing the reaction pH, temperature, and hydroquinone addition amount. Overall, this study successfully constructed a strain with improved conversion rate for the synthetic production of α-arbutin and hydroquinone. These findings have significant implications for reducing the industrial production cost of α-arbutin and enhancing the conversion rate of the product.

Copyright of China Surfactant Detergent & Cosmetics (1001-1803) is the property of China Surfactant Detergent & Cosmetics Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Pulp & Paper is the property of China Pulp & Paper Magazines Publisher and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Coal Science & Technology (0253-2336) is the property of Coal Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Surfactant Detergent & Cosmetics (1001-1803) is the property of China Surfactant Detergent & Cosmetics Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Surfactant Detergent & Cosmetics (1001-1803) is the property of China Surfactant Detergent & Cosmetics Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objective To investigate the effect of hydroquinone (HQ) on the cell cycle of erythroleukemia cell line K562 and its mechanism. Methods K562 cells in the logarithmic phase were selected and then divided into the blank control group and HQ-treated low-dose group,medium-dose group and high-dose group which were treated with 0,15,30,and 60 μmol/L HQ for 72 h at intervals and repeatedly. After 72 h,the cell cycle distribution was detected by flow cytometry,and cell cycle-related protein expression such as CDC25 A,CDK2,CyclinE,CyclinA,p53,p21 and PCNA was detected Western blotting. Results The results of flow cytometry showed that the ratio of cells in the G0/G1 phase of the blank control group and low-dose,medium-dose and high-dose HQ groups was 55. 90% ± 2. 71%,40.16% ± 3. 34%,29. 97%± 1. 23%,and 32. 84% ± 0.93 %,and the ratio of cells in the S phase was 43. 42% ± 2. 61%,57.01% ± 3. 50%,66. 87% ± 1. 77%,and 66. 66% ± 0.31%,and the ratio of cells in the G2/M phase was 0.73% ± 0.78%,3. 27% ±2.05%,4. 40% ± 5.07%,and 0.18% ± 1. 54%,respectively. Therefore,HQ could decrease the proportion of cells in the G0/G1 phase in the K562 cell cycle (P < 0.05),increase the proportion of cells of the S phase (P < 0.05),and induce S phase arrest. Western blotting showed that compared with the blank control group,the expression of CDC25 A protein decreased in each HQ dose group (P < 0.05),and the expression of the high-dose to medium-dose and low-dose HQgroups decreased (P < 0.05). Compared with the blank control group,the expression of CyclinE and PCNA protein in the low-dose group was not statistically different,but the expression in the medium-dose and high-dose HQ groups decreased(P < 0.05). The expression of CyclinE and PCNA protein from the high-dose group to medium-does group and low-dose groups decreased in turn after exposure of HQ (P < 0.05). Compared with the blank control group,the expression of p53 protein in the low-does and medium-dose groups increased (P < 0.05),and the difference in the high-dose group was not statistically significant. There was no significant difference in the expression of CDK2,CyclinA or P21 protein between the blank control group and HQ dose groups (all P > 0.05). Conclusion HQ can induce S phase arrest in K562 cells which might be related to the down-regulated expression of CDC25 A,CyclinE,and PCNA. [ABSTRACT FROM AUTHOR]

Taking uranium tailings treated to hazard-free as the main raw material, a new type of environment functional material-uranium tailings-based porous ceramisite was prepared. The adsorption capacity of uranium tailings porous ceramisite for hydroquinone were investigated. The results indicated that, the removal rate and adsorption capacity of uranium tailings-based porous ceramisite for hydroquinone uranium tailings were 91.2% and 4.56 mg/g respectively with a pH value of 7. During the adsorption of the uranium tailing-based porous ceramsite for hydroquinone, the liquid film diffusion dominated and was more accurately described by the pseudo-first-order kinetic equation. Data fitting degree of Langmuir equation and Koble-Corrigan equation of adsorption isotherm was higher. The adsorption properties of uranium tailings-based porous ceramsite were fixed at a fixed site by a single layer molecular layer, and it was a non-uniform composite adsorption system. The adsorption process of uranium tailings porous ceramisite for hydroquinone was a high fitting for the liquid film diiffusion model. The R² and k value were 0.847 8 and 0.041 7 respectively. [ABSTRACT FROM AUTHOR]

Objective To investigate the role of XPD gene in DNA damage repair of U937 cells induced by hydroquinone ( HQ ) . Methods U937 cells were treated with 5，10，20，40，and 80 μmol/L HQ for 12，24 and 48 h. According to the cell activity，we selected 10，20， and 40 pm ol/L HQ for the following experiments. U937 cells were treated with 10 ，20 and 40 μmol/L HQ for 24 and 48 h ，which were taken as the low-dose，medium-dose，and high-dose HQ groups， meanwhile， the untreated U937 cells were taken as the blank control group. Single cell gel electrophoresis tail moment ( TM ) and Oliv tail moment ( OTM ) were used to detect DNA damage. The relative expression of XPD protein in each group was determined by Western blotting. Results Compared with the blank control group， TM and OTM in the low-dose， medium-dose， and high-dose HQ groups at 24 ，48 h significantly increased ( both P < 0. 05 ). TM and OTM in the low-dose，medium-dose， and high-dose HQ groups at 48 h significantly increased as compared with that of the same group at 24 h ( both P < 0. 05 )，and the TM and OTM values of the low-dose，medium-dose，and high-dose HQ groups increased successively ( both P < 0 .05 ). Compared with the blank control group， the relative expression of XPD protein in the lowdose， medium-dose， and high-dose HQ groups at 24 h was significantly higher ( P < 0 . 05 )， and the high-dose group was significantly higher than the low-dose group ( P < 0. 05 ). The relative expression of XPD protein in the high-dose HQ group at 48 h was significantly higher than that in the blank control group，low-dose，and medium-dose HQ groups ( P < 0 .05 )， but there was no significant difference between the blank control group and low-dose and medium-dose HQ groups ( all P > 0. 05 ). The relative expression of XPD protein in each group at 48 h was not significantly different from that at 24 h ( all P > 0 .05 ). C onclusion The up-regulation of XPD gene expression promotes the repair of DNA damage of U937 cells induced by HQ. [ABSTRACT FROM AUTHOR]

A L-Cysteine/Au/BDD modified electrode was fabricated by electrodeposition of nano-particle of Au and then self-assembly of L-Cysteine on the surface of boron-doped diamond film electrode. The morphology of nano-particles of Au was observed by using scanning electron microscopy, and the electrochemical behaviors and reaction mechanism of the prepared electrode were investigated by cyclic voltammetry. It has been found that, in pH 4.5, 0. 1 mol/L HAc-NaAc solution, the modified electrode exhibited an excellent electro-catalytic effect for the redox of hydroquinone (HQ). By using the chrono-amperometry technique and measuring the oxidation peak current of HQ, an electrochemical assay method was established for the detection of HQ. The linear range is from 2.5 × 10-7 to 2.5 × 10-5mof/L with the detection limit of 3.25 × 10-8 mof/L at a signal-to-noise ratio of 3. This method was adopted to determine HQ in simulated water samples and the recovery was 98.0% - 103.2% . The study may provide a simple, rapid and sensitive method for the determination of HQ presented in natural environment and industrial effluent. [ABSTRACT FROM AUTHOR]

Laboratory incubation experiments were conducted to compare the inhibitory effects of dicyandiamide (DCD) and 3,5-dimethylpyrazole (DMP) on nitrification in meadow-cinnamon soil and fluvo-aquic soil, the main soil types of North China Plain. The synergistic effect of DMP combined with urease inhibitor hydroquinone (HQ) on nitrogen transformation in fluvo-aquic soil was further studied. The results indicated that, in contrast to DCD, DMP had a stronger inhibitory effect on the nitrification in the two tested soils. In comparison with the treatment without any inhibitor, the soil NH4 +-N content in the treatment with DMP increased significantly by 149. 5% -387. 2% at the peak of nitrogen transformation stage, and the soil NO3--N content reduced by 22. 3% - 55. 3%. The inhibitory effects of DCD and DMP in fluvo-aquic soil were both stronger than in meadow-cinnamon soil. In addition, the application of DMP combined with HQ had a significantly synergistic effect on soil nitrogen transformation. [ABSTRACT FROM AUTHOR]

Objective: To investigate the regulatory effect and mechanism of DNA methyltransferase 3A (DNMT3a) in hydroquinone-induced hematopoietic stem cell toxicity., Methods: Cells (HSPC-1) were divided into 4 groups, that is A: normal HSPC-1; B: HQ-intervented HSPC-1; C: group B + pcDNA3 empty vector; D: group B + pcDNA3- DNMT3a. RT-qPCR and Western blot were used to detect the expression levels of DNMT3a and PARP-1 mRNA and protein, respectively. Cell morphology was observe; Cell viability and apoptosis rate of HSPC-1 were detected by MTT and flow cytometry, respectively., Results: Compared with group A, the expression levels of DNMT3a mRNA and protein in HSPC-1 of group B were decreased, while PARP-1 mRNA and protein were increased (P<0.05); there was no significant difference in the above indexes between group C and group B; compared with group B, the expression levels of DNMT3a mRNA and protein showed increased, while PARP-1 mRNA and protein were decreased significantly in cells of group D transfected with DNMT3a (P<0.05). Cells in each group were transfected with DNMT3a and cultured for 24 h, HSPC-1 in group A showed high density growth and mononuclear fusion growth, while the number of HSPC-1 in group B and C decreased and grew slowly. Compared with group B and C, the cell growth rate of group D was accelerated. The MTT analysis showed that cell viability of HSPC-1 in group B were lower than that of group A at 24 h, 48 h and 72 h (P<0.05); after transfected with DNMT3a, the cell viability of HSPC-1 in group D were higher than that of group B at 24 h, 48 h and 72 h (P<0.05). The apoptosis rate of cells in group B was significantly higher than that of group A (P<0.001), while the apoptosis rate in group D was lower than that of group B (P<0.001)., Conclusion: DNMT3a may be involved in the damage of hematopoietic stem cells induced by hydroquinone, which may be related to the regulation of PARP-1 activity by hydroquinone-inhibited DNMT3a.

Objective: A gas chromatography-tandem mass spectrometry detection method for benzene and its metabolites was established to provide methodological support and theoretical basis for the study of benzene toxicity mechanism. Methods: In August 2019 to March 2020, the animal model of containing high concentration of benzene by inhalation of poison through the respiratory tract of mice was established, taken the blood of mice after dyeing the poison, and the HLB solid phase extraction method was used to extract and purify the samples. The gas chromatography-tandem mass spectrometry detection method was used to qualitative and quantitative analysis of the target substances. After separated by HP-17MS capillary chromatographic column, the compounds were ionized with EI ion source, mass spectrometry detection was carried out by selective ion scanning method (SIM) , and quantification was carried out by external standard curve method. Results: Benzene and its metabolites (phenol, catechol, hydroquinone and m-trihydroxybenzene) in blood could be effectively separated and quasi deterministic and quantitative by this method. The regression equations and correlation coefficients of this method for detecting benzene and its metabolites were: benzene: y =3252.1 x +1540, r =0.9993; phenol: y =2046.5 x +1423, r =0.9991; catechol: y =1853.9 x +945, r =0.9993; hydroquinone: y =1891.5 x +840, r =0.9992; m-trihydroxybenzene: y =1052.4 x +655, r =0.9991. The detection limits for benzene, phenol, catechol, hydroquinone and m-trihydroxybenzene were 0.03, 0.03, 0.05, 0.05 and 0.10 μg/g, respectively. And the lower limits of quantification were 0.10, 0.10, 0.15, 0.15 and 0.30 μg/g, respectively. The intra-assay precision interval was 2.64%-10.06%, the inter-assay precision interval was 1.37%-10.17%, and the spike recovery rate was 89.8%-102.3%. This method could be used to quantitatively detect benzene, phenol, catechol, hydroquinone and m-trihydroxybenzene in the blood of benzene-infected mice. Conclusion: Solid phase extraction-gas chromatography-mass spectrometry can be used for qualitative and quantitative detection of benzene and its metabolites (phenol, catechol, hydroquinone and m-trihydroxybenzene) accurately.

In order to improve the activity and working life of metal catalysts in the heterogeneous catalytic ozonation of organic wastewater, four kinds of Mn-Co/ceramic honeycomb (CH) catalysts with different mass ratios of Mn and Co were prepared by coating method using cobalt nitrate hexahydrate [Co(NO 3 ) 2 ·6H 2 O] and manganese nitrate [Mn(NO 3 ) 2 ] as precursors, respectively, and CH as the carrier. The structure of the catalysts was analyzed via X-ray diffraction (XRD), N 2 adsorption/desorption, field emission scanning electron microscopy (FESEM), and X-ray photoelectron spectroscopy (XPS). The mechanical properties of the catalysts were studied. The reaction kinetics model of O 3 alone and catalytic ozonation of the hydroquinone were established and catalytic ozonation performance of catalysts was investigated. The results showed that the crystal phase of Mn 0 Co 1 /CH belonged to CoAl 2 O 4 and that the crystal phase of the Mn-Co/CH catalyst (Mn 1 Co 1 , Mn 2 Co 1 , and Mn 3 Co 1 ) mainly belonged to Mn 3 O 4 and CoO. In particular, the Mn 1 Co 1 /CH catalyst had a large specific surface area of 190 m 2 ·g -1 , high pore volume of 0.25 cm 3 ·g -1 , and pore size of 4.8 nm. The highest catalytic activity was obtained when Mn∶Co was 1∶1 (Mn 1 Co 1 /CH catalyst). The catalytic activity of the Mn 1 Co 1 /CH catalyst was the highest, and removal efficiencies of hydroquinone and COD were 78% and 54%, respectively, using Mn 1 Co 1 /CH catalytic ozonation. The Mn-Co/CH catalyst had a high compressive strength (15.89-16.94 MPa). The degradation efficiency of hydroquinone decreased significantly after the addition of tert-butanol, which indicated that·OH played an important role in the Mn 1 Co 1 /CH catalytic ozonation. The catalytic ozonation process fitted the first-order kinetic model. The apparent rate constant k for O 3 alone was only 0.0306. Furthermore, the Mn 1 Co 1 /CH catalyst had the highest rate, with an apparent rate constant k of 0.0535 min -1 . The Mn-Co/CH catalyst was easy to industrialize owing to its lower consumption, excellent catalytic characteristics, and long working life.