To study the effects of paraphenylenediamine (PPD) and linear alkylbenzene sulphonate (LAS) alone and in combination on the skin. Methods Forty-eight guinea pigs were divided equally into 4 groups and exposed to P...To study the effects of paraphenylenediamine (PPD) and linear alkylbenzene sulphonate (LAS) alone and in combination on the skin. Methods Forty-eight guinea pigs were divided equally into 4 groups and exposed to PPD (4 mg/kg), LAS (12 mg/kg) and PPD (4 mg/kg) plus LAS (12 mg/kg) for 30 days. The biochemical parameters such as acid phosphatase, gtutathione-s-transferase, glutathione peroxidase, glutathione, lipid peroxidafion and histamine contents in exposed skin were estimated. The histopathological examination of the exposed skin was also carried out. Results The skin enzymes, lipid peroxidation, and histamine increased while glutathione decreased in skin. The simultaneously exposed group showed additive toxic effects. The histopathological examination showed severe hyperkeratosis, thickening of collagen fibres and vacuolisation of epidermal cells in PPD plus LAS exposed skin. Conclusion The findings of the present study suggest that simultaneous exposure to PPD and LAS has additive toxic effects.展开更多
Through the hydrogenation experiments for removal of olefin impurities in effluent mixture obtained from alkylation reactor for linear alkylbenzene synthesis, the reaction kinetics was studied. The experimental result...Through the hydrogenation experiments for removal of olefin impurities in effluent mixture obtained from alkylation reactor for linear alkylbenzene synthesis, the reaction kinetics was studied. The experimental results showed that the catalytic activity of Pd/Al2 O3 among four kinds of catalysts was the highest, and the olefin conversion reached 100%when the reaction temperature was higher than 140 ℃. The kinetic model was established through parameters estimation.The experimental validation of the kinetic model showed that the kinetic model had higher simulation accuracy. The results of prediction by the kinetic model indicated that with the intensification of reaction conditions, the olefin conversion would increase and the bromine index of the linear alkyl benzene would decrease. Under the conditions covering a WHSV of 2.0 h^(-1),a temperature of 90 ℃, and a hydrogen partial pressure of 1.5 MPa, the olefin conversion was 99.67%, and the bromine index of the linear alkyl benzene could be reduced to less than 20.00 mgBr/(100 g).展开更多
Oxidation of alkybenzenes PhCH_2R(R=H, CH_3, C_2H_5 and n-C_3H_7) under 1 atm. of O_2 or air catalyzed by iron(Ⅱ, Ⅲ)-2,2'-bipyridine and 1,10-phenanthroline complexes, affords the aryl-substituted ketones and al...Oxidation of alkybenzenes PhCH_2R(R=H, CH_3, C_2H_5 and n-C_3H_7) under 1 atm. of O_2 or air catalyzed by iron(Ⅱ, Ⅲ)-2,2'-bipyridine and 1,10-phenanthroline complexes, affords the aryl-substituted ketones and alcohols with the conversion of 15.00%~34.58% containing of 97.60%~99.80% ketones and alcohols. The turnover numbers of these catalysts are over 3500 mol-cat. ^(-1)for 3.5 h.展开更多
Two new copper complexes based on pyrazole-3-carboxylic acid (H2pca) ligand, Cu(Hpca)2(H2O)2?2H2O (1) and Cu2(pca)2(H2O)4 (2) have been synthesized and fully characterized by single-crystal X-ray diffra...Two new copper complexes based on pyrazole-3-carboxylic acid (H2pca) ligand, Cu(Hpca)2(H2O)2?2H2O (1) and Cu2(pca)2(H2O)4 (2) have been synthesized and fully characterized by single-crystal X-ray diffraction (SXRD), infrared spectroscopy (IR), thermal gravity analysis (TGA), powder X-ray diffraction (PXRD) and elemental analyses. Complex 1 is mononuclear while complex 2 shows a dinuclear structure. Complex 1 crystallizes in the monoclinic system, space group P21/c with Z = 2, a = 6.5591(5), b = 21.696(2), c = 4.9486(2) ?, V = 680.94(9) ?3, F(000) = 366, Dc = 1.745 g/cm3, μ = 1.650 mm-1, the final R = 0.0340 and wR = 0.0792. Complex 2 crystallizes in the monoclinic system, space group P21/n with Z = 2, a = 5.1935(4), b = 9.6052(7), c = 12.7347(9) ?, V = 634.44(8) ?3, F(000) = 420, Dc = 2.195 g/cm3, μ = 3.404 mm-1, the final R = 0.0305 and wR = 0.0653. The three-dimensional frameworks of two complexes are formed by the O?H???O and N?H???O hydrogen bonding interactions. Notably, two copper complexes are further used as catalysts in the oxidation of alkylbenzenes using t-butylhydroperoxide (TBHP) as the oxidant and they exhibit excellent catalytic performance (Conv. up to 98.9%, Sele. up to 98.7%).展开更多
Experimental studies were conducted to explore the fundamental mechanisms of alkali to lower the interfacial tension of oil/heavy alkylbenzene sulfonates (HABS) system. Sodium hydroxide was used as the strong alkali...Experimental studies were conducted to explore the fundamental mechanisms of alkali to lower the interfacial tension of oil/heavy alkylbenzene sulfonates (HABS) system. Sodium hydroxide was used as the strong alkali chemical to investigate the interracial tension (IFT) of oil/HABS system. The influences of salt and alkali on the interracial activity were studied by the measurement of interfacial tension and partition coefficient. Moreover, the al- kali/surfactant solutions were measured by dynamic laser scattering. The results showed that compared with the salt, the function of alkali to lower the interfacial tension and improve partition coefficient is more significant. The mi- celles formed by surfactants could be disaggregated because of adding alkali, so the size of micelles decreases and the number of mono-surfactants increases, then more surfactant molecules move to the interface of oil/surfactant system and the adsorption of surfactants at oil-water interfaces increases, which can lead to the decrease of IFT.展开更多
Adsorption experiments were carried out to investigate the sorption behaviors of naphthalene and phenanthrene in six different soils and to determine the effects of temperature, linear alkylbenzene sulfonate (LAS) a...Adsorption experiments were carried out to investigate the sorption behaviors of naphthalene and phenanthrene in six different soils and to determine the effects of temperature, linear alkylbenzene sulfonate (LAS) and cetylrimethyl ammonium bromide (CTAB) on sorption. The results show that for a given sorbent phenanthrene exhibited greater nonlinear and stronger sorption than naphthalene. There was a strong negative correlation for the Koc values with organic carbon content (foc). The increase of temperature was not favorable to sorption. Sorption decreased along with the increasing aqueous LAS concentration from 0 to 1000 mg/L. At low CTAB concentration (〈 100 mg/L), the adsorption increased as CTAB hemimicelles formed on the soil surface. At high concentration, CTAB decreased the adsorption by occupying active hydrophobic adsorption sites and solubilization of naphthalene and phenanthrene.展开更多
Surfactants are the major active ingredients of laundry detergents. Therefore, special attention should be focused on the treatment and disposal of laundry wastewater. The aim of this study was to characterise the was...Surfactants are the major active ingredients of laundry detergents. Therefore, special attention should be focused on the treatment and disposal of laundry wastewater. The aim of this study was to characterise the wastewater from a commercial laundry over 30 days. Physicochemical analyses were performed, monitoring the content of nitrogen, phosphate, heavy metals, linear alkylbenzene sulphonate (LAS), volatile organic acids and alcohols. The pH was approximately 5.6 and the COD approximately 4800 mg·L-1. The average concentrations of sulphate, sulphide, N-ammoniacal organic nitrogen compounds and heavy metals were below the maximum limit, in accordance with local and national environmental legislation, and the average total suspended solids was 0.08 g·L-1. Among the metals analysed, iron was observed with the highest concentrations (0.037 mg·L-1 and 0.72 mg·L-1). Phosphate was detected in 93% of samples (94.65 mg·L-1 average). LAS was detected in all samples (12.24 mg·L-1 to 1023.7 mg·L-1). Thirty-three different xenobiotic organic compounds were identified in the laundry wastewater with the qualitative screening. The major groups of the compounds were fragrances, preservatives, solvents and some surfactants. Although the characterisation indicated low values for many parameters, this does not eliminate the need for specific treatment before its disposal at the sewage system.展开更多
Linear alkylbenzene(LAB) will be used as solvent for the liquid scintillator in the central detector of Jiangmen Underground Neutrino Observatory. The sheer size of the detector imposes significant challenges and the ...Linear alkylbenzene(LAB) will be used as solvent for the liquid scintillator in the central detector of Jiangmen Underground Neutrino Observatory. The sheer size of the detector imposes significant challenges and the necessity to further improve the optical transparency of high-quality LAB. In order to study high optical transparencies, we continuously improve our measurement setup and use monochromatic light to measure the attenuation lengths of LAB samples. Moreover, the effects of organic impurities on LAB samples are studied to understand their interaction mechanisms and further improve the optical transparency of LAB.展开更多
The catalytic cracking of 1-hexene,1-heptene,1-octene,1-nonene,1-decene,and five olefins mixed with benzene,over USY catalysts was conducted in a small fixed fluidized bed reactor to study the conversion of benzene un...The catalytic cracking of 1-hexene,1-heptene,1-octene,1-nonene,1-decene,and five olefins mixed with benzene,over USY catalysts was conducted in a small fixed fluidized bed reactor to study the conversion of benzene under catalytic cracking conditions.Benzene mainly alkylated with C_(2)-C_(5)light olefins,generating monosubstituted alkylbenzenes,and the concentration of light olefins dramatically affected the alkylbenzene yield.Due to the limitation of thermodynamic equilibrium,the yield of benzene alkylation to alkylbenzene in catalytic cracking was in a relative low level.The equilibrium constant of benzene alkylation decreases with the increasing reaction temperature which resulted in reduction of alkyl benzene yield.展开更多
The micro-morphology and molecular stacking play a key role in determining the charge transport process and nonradiative energy loss, thus impacting the performances of organic solar cells(OSCs). To address this issue...The micro-morphology and molecular stacking play a key role in determining the charge transport process and nonradiative energy loss, thus impacting the performances of organic solar cells(OSCs). To address this issue, a non-fullerene acceptor PhC6-IC-F with alkylbenzene side-chain, possessing optimized molecular stacking, complementary absorption spectra and forming a cascade energy level alignment in the PM6:BTP-eC9 blend, is introduced as guest acceptor to improve efficiency of ternary OSCs. The bulky phenyl in the side-chain can regulate crystallinity and optimizing phase separation between receptors in ternary blend films, resulting in the optimal phase separations in the ternary films. As a result, high efficiencies of 18.33% as photovoltaic layer are obtained for PhC6-IC-F-based ternary devices with excellent fill factor(FF) of 78.92%. Impressively, the ternary system produces a significantly improved open circuit voltage(V_(oc)) of 0.857 V compared with the binary device,contributing to the reduced density of trap states and suppressed non-radiative recombination result in lower energy loss. This work demonstrates an effective approach for adjusting the aggregation, molecular packing and fine phase separation morphology to increase V_(oc) and FF, paving the way toward high-efficiency OSCs.展开更多
In order to improve the cutting performance in broaching,the lubrication and cleaning effects offered by water-based cutting fluids with green additives need to be studied from the viewpoint of green manufacturing.The...In order to improve the cutting performance in broaching,the lubrication and cleaning effects offered by water-based cutting fluids with green additives need to be studied from the viewpoint of green manufacturing.Therefore,water-based solutions with castor oil,surfactant(linear alkylbenzene sulfonate,LAS),and nanographite were prepared by ultrasonic agitation and sprayed into the zone of broaching via atomization.The performances of the cutting fluids,in terms of the viscosity,specific heat,wetting angle,and droplet size,were evaluated to discuss their effects on the broaching load.Among the fluids,the addition of LAS into oil-in-water(WO-S),where its cutting fluid with 10 wt.%castor oil and 1.5 wt.%surfactant,exhibited the lowest broaching force.With regard to the lubricating and cleaning mechanisms,WO-S has good wettability and permeability,and hence,can lubricate the cutting edge of the tool to decrease the cutting load,cool the cutting edge to keep it sturdy,and clean the surface of the cutting edge to keep it sharp.The results reveal that the simultaneous addition of castor oil and LAS had remarkable effects on the lubrication and cleaning,and resulted in a broaching load reduction of more than 10%compared to commercial cutting fluids.However,the addition of nanographite could not improve the lubrication owing to its agglomeration.展开更多
A faradaic response of anionic surfactants (AS),such as linear alkylbenzene sulfonate (LAS),dodecyl benzene sulfonate and dodecyl sulfate,was observed in weak acidic medium. The faradaic response of AS includes (1) a ...A faradaic response of anionic surfactants (AS),such as linear alkylbenzene sulfonate (LAS),dodecyl benzene sulfonate and dodecyl sulfate,was observed in weak acidic medium. The faradaic response of AS includes (1) a catalytic hydrogen wave of AS in HAc/NaAc buffer that was attributed to the reduction of proton associated with the sulfo-group of AS,and (2) a parallel catalytic hydrogen wave of AS in the presence of hydrogen peroxide,which was due to the catalysis of the catalytic hydrogen wave of AS by hydroxyl radical ·OH electrogenerated in the reduction of hydrogen peroxide. The parallel catalytic hydrogen wave is about 50 times as sensitive as the catalytic hydrogen wave. Based on the parallel catalytic hydrogen wave,a high selective method for the determination of AS was developed. In 0.1 mol/L HAc/NaAc (pH=6.2±0.1)/1.0×10 -3 mol/L H_2O_2 supporting electrolyte,the second-order derivative peak current of the parallel catalytic hydrogen wave located at -1.33 V (vs. SCE) was rectilinear to AS concentration in the range of 3.0×10 -6 —2.5×10 -4 mol/L,without the interference of other surfactants. The proposed method was evaluated by quantitative analysis of AS in environmental wastewater.展开更多
The introduction of ionic liquids to alkylation process gives a choice for“green production”in the petrochemical and detergent industry.A lot of papers and patents have been published using chloroaluminate ionic liq...The introduction of ionic liquids to alkylation process gives a choice for“green production”in the petrochemical and detergent industry.A lot of papers and patents have been published using chloroaluminate ionic liquid as a novel catalyst for alkylation with high reactivity and easy separation from reactants.These included the acidity,characterization,determination and catalysis technologies in batch and continuous operation mode for different scales.According to published data and several results of pilot alkylation,including the authors’experience,the prospect of chloroaluminate ionic liquids for commercials was also discussed.It has been pointed out that there still are many difficulties and challenges to be overcome for commercial application of the ionic liquid catalyst.展开更多
文摘To study the effects of paraphenylenediamine (PPD) and linear alkylbenzene sulphonate (LAS) alone and in combination on the skin. Methods Forty-eight guinea pigs were divided equally into 4 groups and exposed to PPD (4 mg/kg), LAS (12 mg/kg) and PPD (4 mg/kg) plus LAS (12 mg/kg) for 30 days. The biochemical parameters such as acid phosphatase, gtutathione-s-transferase, glutathione peroxidase, glutathione, lipid peroxidafion and histamine contents in exposed skin were estimated. The histopathological examination of the exposed skin was also carried out. Results The skin enzymes, lipid peroxidation, and histamine increased while glutathione decreased in skin. The simultaneously exposed group showed additive toxic effects. The histopathological examination showed severe hyperkeratosis, thickening of collagen fibres and vacuolisation of epidermal cells in PPD plus LAS exposed skin. Conclusion The findings of the present study suggest that simultaneous exposure to PPD and LAS has additive toxic effects.
文摘Through the hydrogenation experiments for removal of olefin impurities in effluent mixture obtained from alkylation reactor for linear alkylbenzene synthesis, the reaction kinetics was studied. The experimental results showed that the catalytic activity of Pd/Al2 O3 among four kinds of catalysts was the highest, and the olefin conversion reached 100%when the reaction temperature was higher than 140 ℃. The kinetic model was established through parameters estimation.The experimental validation of the kinetic model showed that the kinetic model had higher simulation accuracy. The results of prediction by the kinetic model indicated that with the intensification of reaction conditions, the olefin conversion would increase and the bromine index of the linear alkyl benzene would decrease. Under the conditions covering a WHSV of 2.0 h^(-1),a temperature of 90 ℃, and a hydrogen partial pressure of 1.5 MPa, the olefin conversion was 99.67%, and the bromine index of the linear alkyl benzene could be reduced to less than 20.00 mgBr/(100 g).
文摘Oxidation of alkybenzenes PhCH_2R(R=H, CH_3, C_2H_5 and n-C_3H_7) under 1 atm. of O_2 or air catalyzed by iron(Ⅱ, Ⅲ)-2,2'-bipyridine and 1,10-phenanthroline complexes, affords the aryl-substituted ketones and alcohols with the conversion of 15.00%~34.58% containing of 97.60%~99.80% ketones and alcohols. The turnover numbers of these catalysts are over 3500 mol-cat. ^(-1)for 3.5 h.
基金supported by the NNSFC(Nos.21401094 and 21501086)the Project of Shandong Province Higher Educational Science and Technology Program(No.J16LC53)the College Students'Science and Technology Innovation Fund(No.CXCY2017028 and CXCY2017037)
文摘Two new copper complexes based on pyrazole-3-carboxylic acid (H2pca) ligand, Cu(Hpca)2(H2O)2?2H2O (1) and Cu2(pca)2(H2O)4 (2) have been synthesized and fully characterized by single-crystal X-ray diffraction (SXRD), infrared spectroscopy (IR), thermal gravity analysis (TGA), powder X-ray diffraction (PXRD) and elemental analyses. Complex 1 is mononuclear while complex 2 shows a dinuclear structure. Complex 1 crystallizes in the monoclinic system, space group P21/c with Z = 2, a = 6.5591(5), b = 21.696(2), c = 4.9486(2) ?, V = 680.94(9) ?3, F(000) = 366, Dc = 1.745 g/cm3, μ = 1.650 mm-1, the final R = 0.0340 and wR = 0.0792. Complex 2 crystallizes in the monoclinic system, space group P21/n with Z = 2, a = 5.1935(4), b = 9.6052(7), c = 12.7347(9) ?, V = 634.44(8) ?3, F(000) = 420, Dc = 2.195 g/cm3, μ = 3.404 mm-1, the final R = 0.0305 and wR = 0.0653. The three-dimensional frameworks of two complexes are formed by the O?H???O and N?H???O hydrogen bonding interactions. Notably, two copper complexes are further used as catalysts in the oxidation of alkylbenzenes using t-butylhydroperoxide (TBHP) as the oxidant and they exhibit excellent catalytic performance (Conv. up to 98.9%, Sele. up to 98.7%).
文摘Experimental studies were conducted to explore the fundamental mechanisms of alkali to lower the interfacial tension of oil/heavy alkylbenzene sulfonates (HABS) system. Sodium hydroxide was used as the strong alkali chemical to investigate the interracial tension (IFT) of oil/HABS system. The influences of salt and alkali on the interracial activity were studied by the measurement of interfacial tension and partition coefficient. Moreover, the al- kali/surfactant solutions were measured by dynamic laser scattering. The results showed that compared with the salt, the function of alkali to lower the interfacial tension and improve partition coefficient is more significant. The mi- celles formed by surfactants could be disaggregated because of adding alkali, so the size of micelles decreases and the number of mono-surfactants increases, then more surfactant molecules move to the interface of oil/surfactant system and the adsorption of surfactants at oil-water interfaces increases, which can lead to the decrease of IFT.
基金supported by the National NaturalScience Foundation of China (No. 40372109)the National Basic Research Program (973) of China (No.2004CB418502).
文摘Adsorption experiments were carried out to investigate the sorption behaviors of naphthalene and phenanthrene in six different soils and to determine the effects of temperature, linear alkylbenzene sulfonate (LAS) and cetylrimethyl ammonium bromide (CTAB) on sorption. The results show that for a given sorbent phenanthrene exhibited greater nonlinear and stronger sorption than naphthalene. There was a strong negative correlation for the Koc values with organic carbon content (foc). The increase of temperature was not favorable to sorption. Sorption decreased along with the increasing aqueous LAS concentration from 0 to 1000 mg/L. At low CTAB concentration (〈 100 mg/L), the adsorption increased as CTAB hemimicelles formed on the soil surface. At high concentration, CTAB decreased the adsorption by occupying active hydrophobic adsorption sites and solubilization of naphthalene and phenanthrene.
基金The authors gratefully acknowledge the Laboratório de Processos Biológicos-LPB/EESC/USP Sao Paulo,Research Foundation(FAPESP)(No 2010/11531-9)the National Council for Scientific and Technological Development for their financial support.
文摘Surfactants are the major active ingredients of laundry detergents. Therefore, special attention should be focused on the treatment and disposal of laundry wastewater. The aim of this study was to characterise the wastewater from a commercial laundry over 30 days. Physicochemical analyses were performed, monitoring the content of nitrogen, phosphate, heavy metals, linear alkylbenzene sulphonate (LAS), volatile organic acids and alcohols. The pH was approximately 5.6 and the COD approximately 4800 mg·L-1. The average concentrations of sulphate, sulphide, N-ammoniacal organic nitrogen compounds and heavy metals were below the maximum limit, in accordance with local and national environmental legislation, and the average total suspended solids was 0.08 g·L-1. Among the metals analysed, iron was observed with the highest concentrations (0.037 mg·L-1 and 0.72 mg·L-1). Phosphate was detected in 93% of samples (94.65 mg·L-1 average). LAS was detected in all samples (12.24 mg·L-1 to 1023.7 mg·L-1). Thirty-three different xenobiotic organic compounds were identified in the laundry wastewater with the qualitative screening. The major groups of the compounds were fragrances, preservatives, solvents and some surfactants. Although the characterisation indicated low values for many parameters, this does not eliminate the need for specific treatment before its disposal at the sewage system.
基金supported by the National 973 Project Foundation of the Ministry of Science and Technology of China(No.2013CB834300)Strategic Pilot Science and Technology Project of the CAS(No.XDA10010000)the National Natural Science Foundation of China(No.116201 004)
文摘Linear alkylbenzene(LAB) will be used as solvent for the liquid scintillator in the central detector of Jiangmen Underground Neutrino Observatory. The sheer size of the detector imposes significant challenges and the necessity to further improve the optical transparency of high-quality LAB. In order to study high optical transparencies, we continuously improve our measurement setup and use monochromatic light to measure the attenuation lengths of LAB samples. Moreover, the effects of organic impurities on LAB samples are studied to understand their interaction mechanisms and further improve the optical transparency of LAB.
文摘The catalytic cracking of 1-hexene,1-heptene,1-octene,1-nonene,1-decene,and five olefins mixed with benzene,over USY catalysts was conducted in a small fixed fluidized bed reactor to study the conversion of benzene under catalytic cracking conditions.Benzene mainly alkylated with C_(2)-C_(5)light olefins,generating monosubstituted alkylbenzenes,and the concentration of light olefins dramatically affected the alkylbenzene yield.Due to the limitation of thermodynamic equilibrium,the yield of benzene alkylation to alkylbenzene in catalytic cracking was in a relative low level.The equilibrium constant of benzene alkylation decreases with the increasing reaction temperature which resulted in reduction of alkyl benzene yield.
基金supported by the National Science Fund for Distinguished Young Scholars(21925506)the National Key R&D Program of China(2017YFE0106000)+3 种基金the National Natural Science Foundation of China(U21A20331,51773212,81903743)Ningbo S&T Innovation 2025 Major Special Programme(2018B10055)CAS Key Project of Frontier Science Research(QYZDB-SSW-SYS030)Ningbo Natural Science Foundation(2021J192)。
文摘The micro-morphology and molecular stacking play a key role in determining the charge transport process and nonradiative energy loss, thus impacting the performances of organic solar cells(OSCs). To address this issue, a non-fullerene acceptor PhC6-IC-F with alkylbenzene side-chain, possessing optimized molecular stacking, complementary absorption spectra and forming a cascade energy level alignment in the PM6:BTP-eC9 blend, is introduced as guest acceptor to improve efficiency of ternary OSCs. The bulky phenyl in the side-chain can regulate crystallinity and optimizing phase separation between receptors in ternary blend films, resulting in the optimal phase separations in the ternary films. As a result, high efficiencies of 18.33% as photovoltaic layer are obtained for PhC6-IC-F-based ternary devices with excellent fill factor(FF) of 78.92%. Impressively, the ternary system produces a significantly improved open circuit voltage(V_(oc)) of 0.857 V compared with the binary device,contributing to the reduced density of trap states and suppressed non-radiative recombination result in lower energy loss. This work demonstrates an effective approach for adjusting the aggregation, molecular packing and fine phase separation morphology to increase V_(oc) and FF, paving the way toward high-efficiency OSCs.
基金This research is supported by National Natural Science Foundation of China(Grant No.51775153).
文摘In order to improve the cutting performance in broaching,the lubrication and cleaning effects offered by water-based cutting fluids with green additives need to be studied from the viewpoint of green manufacturing.Therefore,water-based solutions with castor oil,surfactant(linear alkylbenzene sulfonate,LAS),and nanographite were prepared by ultrasonic agitation and sprayed into the zone of broaching via atomization.The performances of the cutting fluids,in terms of the viscosity,specific heat,wetting angle,and droplet size,were evaluated to discuss their effects on the broaching load.Among the fluids,the addition of LAS into oil-in-water(WO-S),where its cutting fluid with 10 wt.%castor oil and 1.5 wt.%surfactant,exhibited the lowest broaching force.With regard to the lubricating and cleaning mechanisms,WO-S has good wettability and permeability,and hence,can lubricate the cutting edge of the tool to decrease the cutting load,cool the cutting edge to keep it sturdy,and clean the surface of the cutting edge to keep it sharp.The results reveal that the simultaneous addition of castor oil and LAS had remarkable effects on the lubrication and cleaning,and resulted in a broaching load reduction of more than 10%compared to commercial cutting fluids.However,the addition of nanographite could not improve the lubrication owing to its agglomeration.
基金ProjectsupportedbytheNationalNaturalScienceFoundationofChina (No .2 9875 0 17)
文摘A faradaic response of anionic surfactants (AS),such as linear alkylbenzene sulfonate (LAS),dodecyl benzene sulfonate and dodecyl sulfate,was observed in weak acidic medium. The faradaic response of AS includes (1) a catalytic hydrogen wave of AS in HAc/NaAc buffer that was attributed to the reduction of proton associated with the sulfo-group of AS,and (2) a parallel catalytic hydrogen wave of AS in the presence of hydrogen peroxide,which was due to the catalysis of the catalytic hydrogen wave of AS by hydroxyl radical ·OH electrogenerated in the reduction of hydrogen peroxide. The parallel catalytic hydrogen wave is about 50 times as sensitive as the catalytic hydrogen wave. Based on the parallel catalytic hydrogen wave,a high selective method for the determination of AS was developed. In 0.1 mol/L HAc/NaAc (pH=6.2±0.1)/1.0×10 -3 mol/L H_2O_2 supporting electrolyte,the second-order derivative peak current of the parallel catalytic hydrogen wave located at -1.33 V (vs. SCE) was rectilinear to AS concentration in the range of 3.0×10 -6 —2.5×10 -4 mol/L,without the interference of other surfactants. The proposed method was evaluated by quantitative analysis of AS in environmental wastewater.
文摘The introduction of ionic liquids to alkylation process gives a choice for“green production”in the petrochemical and detergent industry.A lot of papers and patents have been published using chloroaluminate ionic liquid as a novel catalyst for alkylation with high reactivity and easy separation from reactants.These included the acidity,characterization,determination and catalysis technologies in batch and continuous operation mode for different scales.According to published data and several results of pilot alkylation,including the authors’experience,the prospect of chloroaluminate ionic liquids for commercials was also discussed.It has been pointed out that there still are many difficulties and challenges to be overcome for commercial application of the ionic liquid catalyst.