2019 Vol. 34, No. 3
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2019, 34(3)
:1-20.
doi: 10.3969/j.issn.2096-1553.2019.03.001
Abstract:
The research results and recent developments of ionic liquids in the main role of the degradation and transformation in cellulose and its derivatives, hemicellulose and its derivatives,lignin and its model compounds were reviewed. Ionic liquids were considered to be solvents and catalysts commonly used in biomass conversion processes. For different types of biomass, ionic liquid/inorganic acid or ionic liquid/metal chloride (Lewis acid) was the mainstream system for postgraduate material conversion catalysts.The problems of the current ionic liquid system in the catalytic conversion of biomass were analyzed. The current ionic liquid system had the problems of high cost and difficult recovery in the application of biomass catalytic conversion. It proposed research directions for further research in the future. The main ones were:one was a new ionic liquid with better synthesis performance to catalyze the conversion of biomass; the second was to develop a new composite catalytic system, specifically a converted additive or catalyst was added into one or more kinds of biomass to dissolve or catalyze the ionic liquid; the third was to develop an ionic liquid catalytic system with low cost, superior performance and easy recovery.
The research results and recent developments of ionic liquids in the main role of the degradation and transformation in cellulose and its derivatives, hemicellulose and its derivatives,lignin and its model compounds were reviewed. Ionic liquids were considered to be solvents and catalysts commonly used in biomass conversion processes. For different types of biomass, ionic liquid/inorganic acid or ionic liquid/metal chloride (Lewis acid) was the mainstream system for postgraduate material conversion catalysts.The problems of the current ionic liquid system in the catalytic conversion of biomass were analyzed. The current ionic liquid system had the problems of high cost and difficult recovery in the application of biomass catalytic conversion. It proposed research directions for further research in the future. The main ones were:one was a new ionic liquid with better synthesis performance to catalyze the conversion of biomass; the second was to develop a new composite catalytic system, specifically a converted additive or catalyst was added into one or more kinds of biomass to dissolve or catalyze the ionic liquid; the third was to develop an ionic liquid catalytic system with low cost, superior performance and easy recovery.
2019, 34(3)
:21-27.
doi: 10.3969/j.issn.2096-1553.2019.03.002
Abstract:
1-N-tetradecyl-3-methylimidazolium dicyanamide salt ([C14mim] [DCA] was synthesized by two-step method using N-methylimidazole, bromotetradecane and dicyandiamide silver as raw materials. The structure of the product was characterized and the interaction of[C14mim] [DCA] with bovine serum albumin (BSA) was studied. The results showed that 1) The cmc value and Amin value of the mixed system increased with the increase of BSA concentration; 2) The interaction between[C14mim] [DCA] and BSA in the mixed system had an effect on the microenvironment of amino acid residues on BSA, and main influenced the tryptophan (Trp) residue on BSA; 3) The interaction between[C14mim] [DCA] and BSA in the mixed system affectd the hydraulic radius of the system, and with the increase of[C14mim] [DCA] concentration, the hydraulic radius of the[C14mim] [DCA]/BSA system became larger and had an effect on the structure of the BSA——BSA was unfolded.
1-N-tetradecyl-3-methylimidazolium dicyanamide salt ([C14mim] [DCA] was synthesized by two-step method using N-methylimidazole, bromotetradecane and dicyandiamide silver as raw materials. The structure of the product was characterized and the interaction of[C14mim] [DCA] with bovine serum albumin (BSA) was studied. The results showed that 1) The cmc value and Amin value of the mixed system increased with the increase of BSA concentration; 2) The interaction between[C14mim] [DCA] and BSA in the mixed system had an effect on the microenvironment of amino acid residues on BSA, and main influenced the tryptophan (Trp) residue on BSA; 3) The interaction between[C14mim] [DCA] and BSA in the mixed system affectd the hydraulic radius of the system, and with the increase of[C14mim] [DCA] concentration, the hydraulic radius of the[C14mim] [DCA]/BSA system became larger and had an effect on the structure of the BSA——BSA was unfolded.
2019, 34(3)
:28-33.
doi: 10.3969/j.issn.2096-1553.2019.03.003
Abstract:
The ionic liquids of 1-butyl-3-methylimidazolium chloride and 1-sulfopropyl-3-methylimidazolium hydrogensulfate were used as solvents and catalysts respectively to hydrolyze cellulose. Then using formic acid as hydrogen source, 2,5-dimethylfuran(DMF) was prepared by catalytic hydrogenation.According to the UV absorption spectrum of the standard samples and Lambert Beer's law,quantitative and qualitative analysis methods for DMF were established to select suitable DMF preparation conditions. The results showed that when the concentration of formic acid was 2 mol·kg-1, the reaction temperature was 343 K and the time was 12 h, the yield of DMF reached a maximum of 41.2%. Compared with the traditional method, the use of ionic liquid enhanced the stability of the system, reduced the specific gravity of the organic solvent, and the reaction process was greener.
The ionic liquids of 1-butyl-3-methylimidazolium chloride and 1-sulfopropyl-3-methylimidazolium hydrogensulfate were used as solvents and catalysts respectively to hydrolyze cellulose. Then using formic acid as hydrogen source, 2,5-dimethylfuran(DMF) was prepared by catalytic hydrogenation.According to the UV absorption spectrum of the standard samples and Lambert Beer's law,quantitative and qualitative analysis methods for DMF were established to select suitable DMF preparation conditions. The results showed that when the concentration of formic acid was 2 mol·kg-1, the reaction temperature was 343 K and the time was 12 h, the yield of DMF reached a maximum of 41.2%. Compared with the traditional method, the use of ionic liquid enhanced the stability of the system, reduced the specific gravity of the organic solvent, and the reaction process was greener.
2019, 34(3)
:34-41.
doi: 10.3969/j.issn.2096-1553.2019.03.004
Abstract:
Three strains screened from the surface of tobacco leaves could be used for inproving tobacco aroma:Bacillus altitudinis (Y2), Bacillus licheniformis (D3), and Bacillus subtilis (L1). They were prepared to single and compound biologics for solid-state fermentation of tobacco, then the routine chemical components, aroma substances of tobacco and petroleum ether extract were detected. The results showed that:the total sugar and reducing sugar content of tobacco leaves decreased after solid-state fermentation of tobacco was inoculated with single strains. The content of aroma substance such as carbonyls, acids and esters in tobacco leaves increased, and the aroma components were also richer. After solid-state fermentation with compound biological agents, the total sugar and reducing sugar content of tobacco leaves decreased, and the treatment consisting of Y2+L1 compound treatment could effectively reduce the content of nicotine and increase the ratio of sugar to alkali.It did not show superposition effect on the aroma components and, on the contrary,it exhibited a completely opposite trend on some aroma substances. D3 treatment or Y2+D3 compound treatment could increase the content of petroleum ether extract and showed strong aroma producing effect.
Three strains screened from the surface of tobacco leaves could be used for inproving tobacco aroma:Bacillus altitudinis (Y2), Bacillus licheniformis (D3), and Bacillus subtilis (L1). They were prepared to single and compound biologics for solid-state fermentation of tobacco, then the routine chemical components, aroma substances of tobacco and petroleum ether extract were detected. The results showed that:the total sugar and reducing sugar content of tobacco leaves decreased after solid-state fermentation of tobacco was inoculated with single strains. The content of aroma substance such as carbonyls, acids and esters in tobacco leaves increased, and the aroma components were also richer. After solid-state fermentation with compound biological agents, the total sugar and reducing sugar content of tobacco leaves decreased, and the treatment consisting of Y2+L1 compound treatment could effectively reduce the content of nicotine and increase the ratio of sugar to alkali.It did not show superposition effect on the aroma components and, on the contrary,it exhibited a completely opposite trend on some aroma substances. D3 treatment or Y2+D3 compound treatment could increase the content of petroleum ether extract and showed strong aroma producing effect.
2019, 34(3)
:42-51.
doi: 10.3969/j.issn.2096-1553.2019.03.005
Abstract:
In order to investigate the puff-by-puff discipline of flavor components in the mainstream cigarette smoking, a 20-channel rotary disc smoker modified from a patent in laboratory was used to achieve the puff-by-puff smoking of cigarettes. A GC-MS quantitative analysis method for neutral and alkaline flavor components in single-mouthful particulate phase of mainstream cigarette smoke was established. By using the established analytical method, the puff-by-puff delivery discipline of flavor components and the effects of the permeability of cigarette paper and packaging paper were studied. The results showed that:1) The established analytical method had a good precision and recovery and was suitable for the quantitative analysis of neutral and alkaline aroma substances in single-mouthful gaseous and granular phase of cigarette smoke. 2) The transport capacity of tar and nicotine in the mainstream cigarette smoke steadily increased with the increase in the number of suction mouths, and decreased with the increase in the permeability of cigarette paper and packaging paper. 3) The transmission of neutral and alkaline aroma components increased with the increase in the number of suction mouths, but the transmission of various flavor components was slightly different, and decreased with the increase of the permeability of cigarette paper and packaging paper. 4) The puff-by-puff contents of neutral and alkaline aroma components in gaseous and granular phase of the mainstream smoke per unit tar and nicotine were the lowest in the first puff, and then were in line with the number of suction puffs.
In order to investigate the puff-by-puff discipline of flavor components in the mainstream cigarette smoking, a 20-channel rotary disc smoker modified from a patent in laboratory was used to achieve the puff-by-puff smoking of cigarettes. A GC-MS quantitative analysis method for neutral and alkaline flavor components in single-mouthful particulate phase of mainstream cigarette smoke was established. By using the established analytical method, the puff-by-puff delivery discipline of flavor components and the effects of the permeability of cigarette paper and packaging paper were studied. The results showed that:1) The established analytical method had a good precision and recovery and was suitable for the quantitative analysis of neutral and alkaline aroma substances in single-mouthful gaseous and granular phase of cigarette smoke. 2) The transport capacity of tar and nicotine in the mainstream cigarette smoke steadily increased with the increase in the number of suction mouths, and decreased with the increase in the permeability of cigarette paper and packaging paper. 3) The transmission of neutral and alkaline aroma components increased with the increase in the number of suction mouths, but the transmission of various flavor components was slightly different, and decreased with the increase of the permeability of cigarette paper and packaging paper. 4) The puff-by-puff contents of neutral and alkaline aroma components in gaseous and granular phase of the mainstream smoke per unit tar and nicotine were the lowest in the first puff, and then were in line with the number of suction puffs.
2019, 34(3)
:52-59.
doi: 10.3969/j.issn.2096-1553.2019.03.006
Abstract:
The effects of acid treatment, alkali treatment and microwave treatment on the enzymatic hydrolysis of tobacco stalks were studied by using tobacco processing by-product tobacco rods as raw materials, and the changes of composition and microstructure of tobacco stalks before and after treatment were analyzed. The results showed that the alkali treatment had a significant effect on the conversion efficiency of tobacco stalks in the three pretreatment methods. The tobacco stalks were treated with a mass fraction of 1% NaOH solution at 75℃ for 120 min, and the glucose content in the hydrolysate was 334.69 mg/g tobacco stalks increased by 118.37% compared to the control sample. The composition analysis showed that the degradation of tobacco lignin by alkali treatment was more obvious, and the degradation rate was 46.45%. Alkali treatment not only destroyed the tobacco lignin benzene ring skeleton, but also modified the benzene ring side chain group, resulting in the disintegration of the lignin macromolecular structure, and the tobacco stalks enzymatic resistance barrier function was reduced, thereby improving the conversion efficiency of tobacco stalks. Alkali treatment did not change the crystallinity of tobacco stalks cellulose, and the increase in crystallinity caused by microwave and acid treatment would adversely affected the efficiency of enzymatic hydrolysis of tobacco stalks.
The effects of acid treatment, alkali treatment and microwave treatment on the enzymatic hydrolysis of tobacco stalks were studied by using tobacco processing by-product tobacco rods as raw materials, and the changes of composition and microstructure of tobacco stalks before and after treatment were analyzed. The results showed that the alkali treatment had a significant effect on the conversion efficiency of tobacco stalks in the three pretreatment methods. The tobacco stalks were treated with a mass fraction of 1% NaOH solution at 75℃ for 120 min, and the glucose content in the hydrolysate was 334.69 mg/g tobacco stalks increased by 118.37% compared to the control sample. The composition analysis showed that the degradation of tobacco lignin by alkali treatment was more obvious, and the degradation rate was 46.45%. Alkali treatment not only destroyed the tobacco lignin benzene ring skeleton, but also modified the benzene ring side chain group, resulting in the disintegration of the lignin macromolecular structure, and the tobacco stalks enzymatic resistance barrier function was reduced, thereby improving the conversion efficiency of tobacco stalks. Alkali treatment did not change the crystallinity of tobacco stalks cellulose, and the increase in crystallinity caused by microwave and acid treatment would adversely affected the efficiency of enzymatic hydrolysis of tobacco stalks.
2019, 34(3)
:60-67.
doi: 10.3969/j.issn.2096-1553.2019.03.007
Abstract:
Using a polar DB-WAX capillary column as the column, n-hexane as the extract, and n-tetradecane as the internal standard, the simultaneous determination of the waterborne adhesives by gas chromatography-tandem mass spectrometry (GC-MS/MS) was established. The method for the content of benzene series and phthalate compounds was investigated and the performance of the method was examined. The results showed that the complete separation of 13 components of benzene series and phthalate compounds was achieved by MRM mode and optimal collision energy conditions at the optimum extraction time of 20 min. The correlation coefficient of this method was >0.999, the detection limit of benzene series was 0.000 8~0.001 0 μg/mL, the limit of quantification was 0.002 5~0.003 0 μg/mL; the detection limit of phthalate compounds was 0.003 0~0.008 0 μg/mL, the limit of quantification was 0.010 0~0.030 0 μg/mL; the recoveries of the two classes of compounds at each spiked concentration level were between 83.2%~99.8%, and the relative standard deviation was less than 7.00%. This indicated that the method had good repeatability and high recovery rate, which could meet the requirements of quantitative analysis, and the limit of quantitation was lower than the industry standard.
Using a polar DB-WAX capillary column as the column, n-hexane as the extract, and n-tetradecane as the internal standard, the simultaneous determination of the waterborne adhesives by gas chromatography-tandem mass spectrometry (GC-MS/MS) was established. The method for the content of benzene series and phthalate compounds was investigated and the performance of the method was examined. The results showed that the complete separation of 13 components of benzene series and phthalate compounds was achieved by MRM mode and optimal collision energy conditions at the optimum extraction time of 20 min. The correlation coefficient of this method was >0.999, the detection limit of benzene series was 0.000 8~0.001 0 μg/mL, the limit of quantification was 0.002 5~0.003 0 μg/mL; the detection limit of phthalate compounds was 0.003 0~0.008 0 μg/mL, the limit of quantification was 0.010 0~0.030 0 μg/mL; the recoveries of the two classes of compounds at each spiked concentration level were between 83.2%~99.8%, and the relative standard deviation was less than 7.00%. This indicated that the method had good repeatability and high recovery rate, which could meet the requirements of quantitative analysis, and the limit of quantitation was lower than the industry standard.
2019, 34(3)
:68-76.
doi: 10.3969/j.issn.2096-1553.2019.03.008
Abstract:
To solve the problem of slow convergence,low precision and poor global search effect of beetle antennae search algorithm (BAS), an improved beetle antennae search algorithm (CDBAS) based on chaotic disturbance mechanism was proposed.The algorithm disturbed the position of longicorn by chaotic mechanism, searched the region with large global fitness value first in iteration, and then searched in the region.Comparation of BAS and CDBAS with 7 test functions showed that CDBAS algorithm had better optimization performance, faster convergence speed and higher accuracy.The CDBAS algorithm was applied to image enhancement. The results showed that the enhancement effect of CDBAS algorithm was more obvious, the image was clearer and the hierarchical information was more abundant.
To solve the problem of slow convergence,low precision and poor global search effect of beetle antennae search algorithm (BAS), an improved beetle antennae search algorithm (CDBAS) based on chaotic disturbance mechanism was proposed.The algorithm disturbed the position of longicorn by chaotic mechanism, searched the region with large global fitness value first in iteration, and then searched in the region.Comparation of BAS and CDBAS with 7 test functions showed that CDBAS algorithm had better optimization performance, faster convergence speed and higher accuracy.The CDBAS algorithm was applied to image enhancement. The results showed that the enhancement effect of CDBAS algorithm was more obvious, the image was clearer and the hierarchical information was more abundant.
2019, 34(3)
:77-83.
doi: 10.3969/j.issn.2096-1553.2019.03.009
Abstract:
Aiming at the problem that the semantics relation among texts is not considered and the amount of computation is too large while samples increases in crossing semantic gap methods,a method of crossing semantic gap was proposed based on semantic kernel SVM combined with improved EMD. Firstly, to solve the semantic relation problem among texts, the method constructed the semantic kernel function based on taking semantic relations of text features into consideration, extracting text features coexisting with images and combining HowNet common ontology repository.Then the semantic kernel function was embedded into the SVM to classify keywords for obtaining best candidate words. Secondly, the algorithm improved EMD with best decreasing matrix to cut down the amount of computation. The experiment result showed that the method proposed takes full consideration of semantic relation in the texts related,the annotation accuracy rate was obviously higher than the other 3 methods and the annotation time was cut down to 1/5 of before.
Aiming at the problem that the semantics relation among texts is not considered and the amount of computation is too large while samples increases in crossing semantic gap methods,a method of crossing semantic gap was proposed based on semantic kernel SVM combined with improved EMD. Firstly, to solve the semantic relation problem among texts, the method constructed the semantic kernel function based on taking semantic relations of text features into consideration, extracting text features coexisting with images and combining HowNet common ontology repository.Then the semantic kernel function was embedded into the SVM to classify keywords for obtaining best candidate words. Secondly, the algorithm improved EMD with best decreasing matrix to cut down the amount of computation. The experiment result showed that the method proposed takes full consideration of semantic relation in the texts related,the annotation accuracy rate was obviously higher than the other 3 methods and the annotation time was cut down to 1/5 of before.
2019, 34(3)
:84-91.
doi: 10.3969/j.issn.2096-1553.2019.03.010
Abstract:
Aim at the low real-time performance and high false alarm rate of the traditional fall detection model,AdaBoost multi-core support vector machine model (ADB-MKSVM) was proposed which was used to detect and identify the falling action. Based on the improved AdaBoost model framework, the model took multi-core support vector machine as the basis classifier and assembled these basis classifiers to form a stronger final classifier. According to the distribution of human movement data and whether the classification of each sample in each training set is correct or not, and the overall classification accuracy last time, the weight of each sample was determined. The dynamic weight allocation method was used to improve the recognition rate of the fall action. The test results showed that this model had good classification performance, and the method of binding the sensor on the waist position could effectively improve the detection effect of the fall action.The accuracy rate was 99.33%,the fall detection rate was 63.6%,and the false detection rate was 1.62%.
Aim at the low real-time performance and high false alarm rate of the traditional fall detection model,AdaBoost multi-core support vector machine model (ADB-MKSVM) was proposed which was used to detect and identify the falling action. Based on the improved AdaBoost model framework, the model took multi-core support vector machine as the basis classifier and assembled these basis classifiers to form a stronger final classifier. According to the distribution of human movement data and whether the classification of each sample in each training set is correct or not, and the overall classification accuracy last time, the weight of each sample was determined. The dynamic weight allocation method was used to improve the recognition rate of the fall action. The test results showed that this model had good classification performance, and the method of binding the sensor on the waist position could effectively improve the detection effect of the fall action.The accuracy rate was 99.33%,the fall detection rate was 63.6%,and the false detection rate was 1.62%.
2019, 34(3)
:92-102.
doi: 10.3969/j.issn.2096-1553.2019.03.011
Abstract:
By using the concept of comparison function, the asymptotic behavior of the intermediate point function of the high order Cauchy mean value theorem was studied. Under certain conditions, a broader asymptotic estimate of the intermediate point function of the high order Cauchy mean value theorem was established. The first-order differentiability of the intermediate point function of the high order Cauchy mean value theorem was obtained. The obtained results generalized and improved the results in the relevant literature,and enriched the theory of the median theorem.
By using the concept of comparison function, the asymptotic behavior of the intermediate point function of the high order Cauchy mean value theorem was studied. Under certain conditions, a broader asymptotic estimate of the intermediate point function of the high order Cauchy mean value theorem was established. The first-order differentiability of the intermediate point function of the high order Cauchy mean value theorem was obtained. The obtained results generalized and improved the results in the relevant literature,and enriched the theory of the median theorem.
2019, 34(3)
:103-108.
doi: 10.3969/j.issn.2096-1553.2019.03.012
Abstract:
The existence of fixed point for integral type orbitally contractive mappings in complete metric spaces and 2-metric spaces was studied, the fixed point theorem for integral type orbitally contractive mappings was proved under certain conditions, which extended some known results in the related literature to integral φ-φ-type orbital compression mapping class and integral Altman type orbital compression mapping class.
The existence of fixed point for integral type orbitally contractive mappings in complete metric spaces and 2-metric spaces was studied, the fixed point theorem for integral type orbitally contractive mappings was proved under certain conditions, which extended some known results in the related literature to integral φ-φ-type orbital compression mapping class and integral Altman type orbital compression mapping class.
Journal Information
Founded in 1986， bimonthly
Administered by：The Education Department Henan Province
Sponsored by：Zhengzhou University of Light Industry
Editor-in-chief：Wei Shizhong
Executive Editor-in-Chief：Zou Lin
Subeditor：Qu Shuanghong
Edited & published by：Editorial Department of Journal of Light Industry
CN 41-1437/TS
ISSN 2096-1553
Address：136 Science Avenue, Zhengzhou City, Henan Province, China
Postal Code：450001
Tel：(086)0371-86608635
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