聚邻氨基对酚磺酸修饰电极测定尿酸

A poly(2-Amino-Phenol-P-Sulphonic acid)Modified Electrode was prepared by cyclic voltammetry and the electrochemical behavior of Uric Acid(UA)on this modified electrode was studied.The result was showed that this modified electrode has strong electrocatalytic functionality for UA,and strong anti-jamming impact for Ascorbic acid(AA).In pH=5.6 KH2PO4-Na2HPO4 buffer solution,use cyclic voltammetry and difference pulse voltammetry,the linear rang for determining UA was 8.0×10-6mol/L～2.0×10-4 mol/L(CV)and 4.0×10-7mol/L～1.0×10-5mol/L(DPV),The detection limit is 6.0×10-6 mol/L and 1.0×10-7 mol/L.Use of this method for measurement of UA in urine obtained satisfactory results.

我厂对叔丁基苯酚装置的增产途径

一、前言 对叔丁基苯酚(以下简称“对酚”)是一种应用广泛的化工原料,可用来合成油溶性酚醛树脂,作光气法聚碳酸脂的反应终止剂,环氧树脂、二甲苯树脂的改性剂,PVC的稳定剂等。此外还可用于建筑、制鞋、油墨等行业。

Experimental and Simulation Study on the Extraction of p-Cresol Using Centrifugal Extractors

In this study,extraction of p-cresol from the simulated wastewater has been studied using centrifugal extractors and QH-1 extractant.The distribution ratio of p-cresol was approximately 308.5 in the QH-1-p-cresol(pH=2.0)system.The extraction stage efficiency of the single-stage centrifugal extractor was higher than 92%,and the extraction rate of the three-stage cascade was higher than 99%.When 15% NaOH was used for the stripping of p-cresol in QH-1 solution,the stripping rate of the three-stage cascade reached 100%.A mathematical model of multistage countercurrent extraction process that considers the phase volume change,extraction stage efficiency,and phase entrainment was used to simulate the extraction of p-cresol using centrifugal extractors.The calculated results using this model were in good agreement with the experimental results.

The Effect of Titania Structure on Ni/TiO_2 Catalysts for p-Nitrophenol Hydrogenation

The catalytic hydrogenation of p-nitrophenol to p-aminophenol was investigated over Ni/TiO2 catalysts prepared by a liquid-phase chemical reduction method. The catalysts were characterized by inductively coupled plasma (ICP), X-ray powder diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectra (XPS) and temperature-programmed reduction (TPR). Results show that the titania structure has favorable influence on physio-chemical and catalytic properties of Ni/TiO2 catalysts. Compared to commercial Raney nickel, the catalytic activity of Ni/TiO2 catalyst is much superior, irrespective of the titania structure. The catalytic activity of anatase titania supported nickel catalyst Ni/TiO2(A) is higher than that of rutile titania supported nickel catalyst Ni/TiO2(R), possibly because the reduction of nickel oxide to metallic nickel for Ni/TiO2(A) is easier than that for Ni/TiO2(R) at similar reaction conditions.

Distinct synergetic effects in the ozone enhanced photocatalytic degradation of phenol and oxalic acid with Fe^(3+)/TiO_2 catalyst

In this work. phenol and oxalic acid （OA） degradation in an ozone and photocatalysis integrated process was intensively conducted with Fe3 ＋/TiO2 catalyst. The ferrioxalate complex formed between Fe3＋ and oxalate accelerated the removal of OA in the ozonation, photolysis and photocatalytic ozonation process, for its high reactivity with ozone and UV. Phenol was degraded in ozonation and photolysis with limited TOC removal rates, but much higher TOC removal was achieved in photocatalytic ozonation due to the generation of-OH. The sequence of UV light and ozone in the sequential process also influences the TOC removal, and ozone is very powerful to oxidize intermediates catechol and hydroquinone to maleic acid. Fenton or photo-Fenton reactions only played a small part in Fe3＋/TiO2 catalyzed processes, because Fe＋ was greatly reduced but not regenerated in many cases. The synergetic effect was found to be highly related with the property of the target pollutants. Fe3 ＋/TiO2 catalyzed system showed the highest ability to destroy organics, but the TiO2 catalyzed system showed little higher synergy.

Alkylation of p-Cresol with tert-Butanol Catalyzed by Novel Multiple-SO_3H Functioned Ionic Liquid

The alkylation of p-cresol with tert-butanol（TBA）to 2-tert-butyl-p-cresol（TBC）catalyzed by a novel multiple-SO3H functioned ionic liquid（IL1）was investigated.Meanwhile,the catalytic activity of this novel ionic liquid was compared with other four traditional ionic liquids.The results showed that IL1 has superior catalytic activity to other four traditional ionic liquids with the conversion of 85.3%and selectivity of 95.2%.Also,the reaction conditions were investigated to obtain the optimum conditions.Operational simplicity,small amount of usage,high activity,reusability and selectivity are the key features of this methodology.

Versatile bifunctional nitrogen-doped porous carbon derived from biomass in catalytic reduction of 4-nitrophenol and oxidation of styrene

The scarcity and weak durability of metal,especially precious metal catalysts are big obstacles for their large-scale application in many reactions.The state-of-the-art of the catalytic science prefers such type of catalysts,which can replace metal-based catalysts to alleviate energy and environmental crises and exhibit catalytic performance comparable to or even exceeding these metal catalysts.Herein,we report that N-doped porous carbon(NKC)derived from cheap and abundant radish can be employed as versatile and efficient bifunctional catalysts in both the catalytic reduction of 4-nitrophenol(NRR)and oxidation of styrene(SOR).The series of NKC catalysts were prepared with a simple and facile one-pot strategy by coupling the N-doping,carbonization and KOH activation processes.These catalysts show hierarchical porosity,with the specific surface area,total pore volume and N-doping content ranging from 918.9-3062.7 m^2 g^-1,1.01-2.04 cm^3 g^-1 and 1.29-15.3 at%,respectively.Interestingly,our finding suggests that the catalytic performance is not directly related to these parameters but correlates positively with the content of graphitic N dopants,which is the dominant contributor for impelling both the NRR and SOR.Another intriguing finding is that for both reactions,the optimal catalyst was found to be the NKC-3-800 which possesses the highest graphitic N content of 3.13 at%.In addition,to gain insight into the catalytic behavior,analyses of kinetics and thermodynamics were performed,and the catalytic mechanisms were postulated.This work paves the way for the construction of biomass-derived N-doped carbon catalysts for bi-or even multi-functional applications in various organic reactions.

Liquid-Liquid-Liquid Three Phase Extraction Apparatus:Operation Strategy and Influences on Mass Transfer Efficiency

Abstract A new mixer-settler-mixer three chamber integrated extractor is proposed in this work for liquid-liquid- liquid three phase countercurrent and continuous extraction. Experiments revealed the influences of the structural design of the three-liquid-phase extractor and some key operational parameters on three-phase partition of two phenolic isomers, p-nitrophenol （p-NP） and o-nitrophenol （o-NP）. The model three-liquid-phase extraction system used here is nonane （organic top-plaase）-polyethylene glycol （PEG 20UU） （polymer mlddle-phase）-（NH4）2SO4 aqueous solution （aqueous bottom-phase）. It is indicated that agitating speed and retention time in three-phase mixer are key parameters to extraction fraction of nitrophenol. Dispersion band behavior is related to agitating intensity, and its occurrence does not affect the extraction fraction of target compounds. The present work highlights the possibility of a feasible approach of scaling up of the proposed three-phase extraction apparatus for future in- dustrial-aimed applications.

Measurements and thermodynamic modeling of liquid–liquid equilibria in ternary system 2-methoxy-2-methylpropane+p-cresol+water

Liquid-liquid equilibrium （LLE） data for the ternary system 2-methoxy-2-methylpropane （methyl tert-butyl ether） ＋ p-cresol ＋ water was measured at atmospheric pressure and temperatures of 298.15 K and 313.15 K. From the distribution coefficients and selectivity, it was found that 2-methoxy-2-methylpropane is an efficient solvent to extract p-cresol from wastewater. The consistency of the experimental tie-line data was verified with the Hand and Bachman equations. These data were also correlated with the non-random two liquid （NRTL） and universal quasi-chemical correlation activity coefficient （UN1QUAC） models to yield binary interac- tion parameters for p-cresol extraction process evaluation. Both models agreed with experiments very well, yet the NRTL model showed even smaller average deviation than the UNIQUAC model.

The roles of serine protease, intracellular and extracellular phenoloxidase in activation of prophenoloxidase system, and characterization of phenoloxidase from shrimp haemocytes induced by lipopolysaccharide or dopamine

We investigated the effects of lipopolysaccharide （LPS） and dopamine （DA） on the activation of the prophenoloxidase （proPO） system of Litopenaeus vannamei. LPS and DA were shown with a negative dose-dependent effect on hyalne cells （HC）, semi-granular cells （SGC）, large granular cells （LGC）, and total haemocyte count （THC）. When haemocytes were treated with LPS or DA, serine proteinase activity and intracellular phenoloxidase （PO） activity were significantly reduced, but extracellular PO activity increased significantly. These findings indicated that the reduction in haemocyte counts was mainly because of the degranulation and activation of the proPO system from semi-granule and large granule cells. The PKC inhibitor, chelerythrine, and the TPK inhibitor, genistein, had an inhibitory effect on extracellular PO activity, while serine proteinase and intracellular PO activity increased. This suggests that the LPS and DA induce the activation of proPO in haemocytes via PKC and TPK-related signaling pathways, but serine proteinase may be activated only by PKC, as the genistein effects were not statistically significant. Electrophoresis analysis revealed that POs induced by LPS or DA have the same molecular mass and high diphenolase activity. Two PO bands at 526 kDa and 272 kDa were observed in PAGE, while in the haemocyte lysate supematant （HLS）, only a 272-kDa band was observed. This band was resolved after SDS-PAGE under non-reducing and reducing conditions into two groups of POs, 166 kDa and 126 kDa, and 78.1 kDa and 73.6 kDa, respectively, suggesting that PO in L. vannamei is an oligomer, which may have different compositions intra- and extracellularly.

Plasma microRNA profiles distinguish lethal injury in acetaminophen toxicity: A research study

AIM: To investigate plasma microRNA (miRNA) profiles indicative of hepatotoxicity in the setting of lethal acetaminophen (APAP) toxicity in mice. METHODS: Using plasma from APAP poisoned mice, either lethally (500 mg/kg) or sublethally (150 mg/kg) dosed, we screened commercially available murine microRNA libraries (SABiosciences, Qiagen Sciences, MD) to evaluate for unique miRNA profiles between these two dosing parameters. RESULTS: We distinguished numerous, unique plasma miRNAs both up- and downregulated in lethally compared to sublethally dosed mice. Of note, many of the greatest up- and downregulated miRNAs, namely 574-5p, 466g, 466f-3p, 375, 29c, and 148a, have been shown to be associated with asthma in prior studies. Interestingly, a relationship between APAP and asthma has been previously well described in the literature, with an as yet unknown mechanism of pathology. There was a statistically significant increase in alanine aminotransferase levels in the lethal compared to sublethal APAP dosing groups at the 12 h time point (P < 0.001). There was 90% mortality in the lethally compared to sublethally dosed mice at the 48 h time point (P = 0.011). CONCLUSION: We identified unique plasma miRNAs both up- and downregulated in APAP poisoning which are correlated to asthma development.

Protective effects of 5-methoxypsoralen against acetaminophen-induced hepatotoxicity in mice

AIM:To investigate the hepatic protective effects of 5-methoxypsoralen(5-MOP) and to learn if 5-MOP causes hepatotoxicity at protective doses.METHODS:C57BL/6J mice were administrated orally with 5-MOP at doses of 12.5,25 and 50 mg/kg body weight respectively every morning for 4 d before given acetaminophen(APAP) subcutaneously at a dose of 500 mg/kg.The 5-MOP alone group was treated with 5-MOP orally at a dose of 50 mg/kg body weight for 4 d without APAP.Twenty-four hours after APAP administration,blood samples of mice were analyzed for serum enzyme alanine transaminase(ALT),aspartate transaminase(AST),lactate dehydrogenase(LDH) levels,and malondialdehyde(MDA),reduced glutathione(GSH) and oxidized glutathione(GSSG) of liver tissues were measured and histopathologic changes of the liver were observed.RESULTS:Compared with the vehicle control group,the serum levels(IU/L) of ALT,AST and LDH were all increased significantly in APAP group(8355 ± 3940 vs 30 ± 21,P < 0.05;6482 ± 4018 vs 146 ± 58,P <0.05;24627 ± 10975 vs 1504 ± 410,P < 0.05).Compared with APAP group,the serum ALT levels(IU/L)(1674 ± 1810 vs 8355 ± 3940,P < 0.05;54 ± 39 vs 8355 ± 3940,P < 0.05;19 ± 9 vs 8355 ± 3940,P < 0.05),AST levels(IU/L)(729 ± 685 vs 6482 ± 4108,P < 0.05;187 ± 149 vs 6482 ± 4108,P < 0.05;141 ± 12 vs 6482 ± 4108,P < 0.05) and LDH levels(IU/L)(7220 ± 6317 vs 24 627 ± 10 975,P < 0.05;1618 ± 719 vs 24 627 ± 10 975,P < 0.05;1394 ± 469 vs 24 627 ± 10 975,P < 0.05) were all decreased drastically in the three-dosage 5-MOP pretreatment groups.Pretreatment of 5-MOP could attenuate histopathologic changes induced by APAP,including hepatocellular necrosis and infiltration of inflammatory cells,and the effect was dose-dependent.MDA levels(nmol/mg) were decreased by 5-MOP in a dose-dependent manner(0.98 ± 0.45 vs 2.15 ± 1.07,P > 0.05;0.59 ± 0.07 vs 2.15 ± 1.07,P < 0.05;0.47 ± 0.06 vs 2.15 ± 1.07,P < 0.05).The pretreatment of 5-MOP could also increase the GSH/GSSG ratio(3.834 ± 0.340 vs 3.306 ± 0.282,P > 0.05;5.330 ± 0.421 vs 3.306 ± 0.282,P < 0.05;6.180 ± 0.212 vs 3.306 ± 0.282,P < 0.05).In the group treated with 5-MOP but without APAP,the serum enzyme levels,the liver histopathologic manifestation,and the values of MDA and GSH/GSSG ratio were all normal.CONCLUSION:5-MOP can effectively protect C57BL/6J mice from APAP-induced hepatotoxicity and possesses an antioxidative activity,and does not cause liver injury at the protective doses.

Preparation, Characterization and Biological Activity Studies of New Azo Compounds

A new series of azo were derived from 2,5-di（p-amino phenyl）-3,6-diphenyl pyrazine in the presence of benzoic acid, salicylic acid, p-amino salicylic acid, p-methoxy phenol and pmethyl phenol. The structures of the synthesized compounds were determined on the basis of their FTIR, UV （ultraviolet）, elemental analysis and H-NMR （H-nuclear magnetic resonance） spectral date. The purity of synthesized compounds was checked by performing TLC （thin layer chromatography）. The antibacterial activity was evaluated in DMSO （dimethyl sulfoxide）.

Factors associated with irritable bowel syndrome symptoms in hemodialysis patients

AIM: To investigate clinical characteristics associated with the presence of irritable bowel syndrome (IBS) symptoms in hemodialysis (HD) patients.METHODS: This was a cross-sectional study. A questionnaire based on the Bowel Disease Questionnaire that records gastrointestinal symptoms was given to 294 patients in 4 dialysis centers. A total of 196 (67%) subjects returned the survey. A multivariable logistic regression model was used to identify factors significantly associated with IBS symptoms. RESULTS: Symptoms compatible with IBS were present in 27 (13.8%) subjects and independently associated with low post-dialysis serum potassium [OR = 0.258, 95% CI (0.075-0.891), P = 0.032], paracetamol use [OR = 3.159, 95% CI (1.214-8.220), P = 0.018], and Kidney Disease Quality of Life (KDQOL) cognitive function score [OR = 0.977, 95% CI (0.956-0.999), P = 0.042]. Univariate regressions were also performed and the reported significance is for multivariate analysis. No association was detected for age, gender, depressed mood, smoking (present or past), body mass index, albumin level, Kt/V, sodium preor post-dialysis level, change in potassium level during HD, proton pump inhibitor or H2 blocker use, aspirin use, residual diuresis, hepatitis B or C infection, diabetes mellitus, marital status and education level. CONCLUSION: This study examined potential risk factors for symptoms compatible with IBS in HD patients and identified an association with paracetamol use, post-dialysis potassium level and KDQOL-cognitive function score.

Effect of Lianshu preparation on lipopolysaccharide-induced diarrhea in rats

AIM： To investigate the effect of Lianshu preparation on lipopolysaccharide （LPS）-induced diarrhea in rats. METHODS： A diarrhea model was established in Sprague Dawley rats via injection of 1 mL of 30 mg/kg LPS. A total of 40 rats were randomly divided into normal group, LPS group, LPS ＋ Lianshu group, LPS ＋ berberine group （n = 10 in each group）. Their intestinal mucosal barrier and frequency of diarrhea were observed. Levels of glucose, serum Na^＋, K^＋, Cl and hematocrit, plasma nitrogen monoxide （NO）, diamine oxidase （DAO）, and D （-）-lactate were measured. The number of IgA＋ plasma cells in small intestine was detected and SIgA levels in the intestinal fluid were measured. The antipyretic activity of Lianshu preparation in rats was evaluated using Brewer＇s yeast-induced pyrexia （10 mL/kg of 20% aqueous suspension）. Acetaminophen （250 mg/kg, intragastric administration, bid） was comparison. Temperature used as a standard drug for was recorded 1 h before and 6 h after Brewer＇s yeast injection. Finally, small intestina transmission in mice treated with Lianshu was detected after intraperitoneal injection of methyl prostigmin （2 mg/kg）. Atropine （10 g/kg） was used as a control. The ink content in intestine was determined and the total length of intestine was measured. RESULTS： The frequency of diarrhea was higher in LPS group than in LPS ＋ Lianshu group and LPS ＋ berberine group （36.70± 5.23 vs 28.50 ±4.06 and 32.70±9.30 respectively, P 〈 0.01）, and lower in LP5 ＋ Lianshu group than in LPS ＋ berberine group （P = 0.03）. The levels of Na＋, glucose, Cl, K^＋ were significantly lower in LPS ＋ Lianshu group than in LPS ＋ berberine group （140.35±3.19 mmol/L vs 131.99±4.86 mmol/L, 8.49 ±1.84 mmol/L vs 6.54±2.30 mmol/L, 106.29± 4.41 mmol/L vs 102.5±1.39 mmol/L, 5.08±0.66 mmol/L vs 4.32 ± 0.62 mmol/L respectively, P 〈 0.05）. The level of hematocrit was lower in LPS ＋ Lianshu group than in LPS ＋ berberine group （0.50% ±0.07% vs 0.59%± 0.10% respectively, P 〈 0.05）. The plasma levels of NO, DAO and D （-）-lactate were higher in LPS group than in normal group （79.74 ± 7.39μmol/L vs 24.94 ± 3.38μmol/L, 2.48 ±0.42μ/mL vs 0.82 ±0.33 p/mL, 5.63± 0.85μg/mL vs 2.01 ±0.32 μg/mL respectively, P 〈 0.01）, and lower in LPS ＋ Lianshu group than in LP5 ＋ berberine group （48.59±4.70μmol/L vs 51.56 ±8.38 μmol/L, 1.43± 0.53μmol/mL vs 1.81 ±0.42 μmol/mL, 4.00± 0.54 μg/mL vs 4.88 ± 0.77 pg/mL respectively, P 〈 0.05）. The morphology of the intestinal mucosa showed destroyed villi in LPS group and atrophied intestinal mucosa in other groups. The pathological intestinal mucosal changes were less in LPS ＋ Lianshu group than in LPS group. The number of IgA＋ plasma cells and amount of SIgA were higher in LPS ＋ Lianshu group than in LPS group （1.16±0.19/μm^2 vs 1.09±0.28/μm^2, P = 0.026; 0.59 ±0.12 mg/L vs 0.15± 0.19 mg/L respectively, P = 0.000）. Lianshu had counteractive effects on yeast-induced pyrexia and enterokinesia in rats. CONCLUSION： Lianshu preparation has therapeutic effects on LPS-induced diarrhea and enterokinesia in rats.

Catalytic Decomposition of Chlorophenols Using Fiber-supported Cobalt Phthalocyanine

A novel heterogeneous catalyst, viscose fiber- supported cobalt phthalocyanine （Co - TDTAPc - F）, was prepared by immobilizing cobalt tetra（2.4 - dichloro- 1,3, 5 -triazine）aminophtbalocyanine （Co- TDTAPc） on viscose fibers covalcntly. The oxidative removal of chlorophenols such as 2 - chlorophenoi, 4 - chlorophenol, 2, 4 - dichlorophenol, and 2, 4, 6 - trichlorophenol was investigated in the catalytic oxidative system of Co - TDTAPc- F/H2O2. Furthermore, more than 98% of these chloropbenols were decomposed in 4 h. Phenol, oxalic acid, maleic acid, and succinic acid, etc., were detected by high performance liquid chromatography （HPLC） and gas chromatography-mass spectrophotometer （GC - MS）, and these short-chain organic acids could be further oxidized easily. The results indicated that the catalytic oxidation in the Co- TDTAPc - F/H2O2 system leaded to a deeper oxidation. In addition, a degradation pathway for chlorophenols was proposed on the basis of detection of intermediate compounds.

Protective effects of 2,4-dihydroxybenzophenone against acetaminophen-induced hepatotoxicity in mice

AIM:To examine the effects of 2,4-dihydroxybenzophenone(BP-1),a benzophenone derivative used as an ultraviolet light absorbent,on acetaminophen(APAP)induced hepatotoxicity in C57BL/6J mice.METHODS:Mice were administered orally with BP-1 at doses of 200,400 and 800 mg/kg body weight respectively every morning for 4 d before a hepatotoxic dose of APAP(350 mg/kg body weight) was given subcutaneously.Twenty four hours after APAP intoxication,the serum enzyme including serum alaine aminotransferase(ALT),aspartate aminotransferase(AST),lactate dehydrogenase(LDH) were measured and liver histopathologic changes were examined.RESULTS:BP-1 administration dramatically reduced serum ALT,AST and LDH levels.Liver histopathological examination showed that BP-1 administration antagonized APAP-induced liver pathological damage in a dose-dependent manner.Further tests showed that APAP-induced hepatic lipid peroxidation was reduced significantly by BP-1 pretreatment,and glutathione depletion was ameliorated obviously.CONCLUSION:BP-1 can effectively protect C57BL/6J mice from APAP-induced hepatotoxicity,and reduction of oxidative stress might be part of the protection mechanism.

Impaired gluconeogenesis in a porcine model of paracetamol induced acute liver failure

AIM:To investigate glucose homeostasis and in particular gluconeogenesis in a large animal model of acute liver failure(ALF).METHODS:Six pigs with paracetamol induced ALF under general anaesthesia were studied over 25 h.Plasma samples were withdrawn every five hours from a central vein.Three animals were used as controls and were maintained under anaesthesia only.Using 1 H NMR spectroscopy we identified most gluconeogenic amino acids along with lactate and pyruvate in the animal plasma samples.RESULTS:No significant changes were observed in the concentrations of the amino acids studied in the animals maintained under anaesthesia only.If we look at the ALF animals,we observed a statistically significant rise of lactate(P<0.003)and pyruvate(P<0.018) at the end of the experiments.We also observed statistically significant rises in the concentrations of alanine(P<0.002),glycine(P<0.005),threonine(P< 0.048),tyrosine(P<0.000),phenylalanine(P<0.000) and isoleucine(P<0.01).Valine levels decreased significantly(P<0.05).CONCLUSION:Our pig model of ALF is characterized by an altered gluconeogenetic capacity,an impaired tricarboxylic acid(TCA)cycle and a glycolytic state.