2021 Vol. 36, No. 4
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2021, 36(4)
:1-8.
doi: 10.12187/2021.04.001
Abstract:
In order to produce the xylanase efficiently, the effects of the culture medium composition and content in a 100 L fermentation tank on the xylanase fermentation were investigated with the high-yield methanol protein strain of Pichia pastoris selected by mutagenesis in our lab. The ratio of the medium was determined. Then, the orthogonal experimental scheme was designed to optimize the ratio of the medium. The result showed that the optimal components of fermentation medium were mass concentration of phosphoric acid of 25 g/L, dipotassium hydrogen phosphate of 0. 5 g/L, ammonium chloride of 0. 3 g/L, calcium sulfate dihydrate of 0. 25 g/L, sodium chloride of 0. 6 g/L, potassium sulfate of 3. 0 g/L, and magnesium sulfate heptahydrate of 2. 2 g/L; under the optimal medium formula, the wet weight of fermentation reached 409~417 g/L, and the xylanase activity reached 40 915~41 428 U/mL.
In order to produce the xylanase efficiently, the effects of the culture medium composition and content in a 100 L fermentation tank on the xylanase fermentation were investigated with the high-yield methanol protein strain of Pichia pastoris selected by mutagenesis in our lab. The ratio of the medium was determined. Then, the orthogonal experimental scheme was designed to optimize the ratio of the medium. The result showed that the optimal components of fermentation medium were mass concentration of phosphoric acid of 25 g/L, dipotassium hydrogen phosphate of 0. 5 g/L, ammonium chloride of 0. 3 g/L, calcium sulfate dihydrate of 0. 25 g/L, sodium chloride of 0. 6 g/L, potassium sulfate of 3. 0 g/L, and magnesium sulfate heptahydrate of 2. 2 g/L; under the optimal medium formula, the wet weight of fermentation reached 409~417 g/L, and the xylanase activity reached 40 915~41 428 U/mL.
2021, 36(4)
:9-17.
doi: 10.12187/2021.04.002
Abstract:
The gelatin-chitosan-cinnamon essential oil natural coating solution was prepared by the self-assembly method, and the particle size of the natural coating solution and its encapsulation rate of cinnamon essential oil were used as indicators. On the basis of single factor test, orthogonal test was used to determine the optimal process for preparing natural coating solution. The antibacterial effect of the natural coating solution by the antibacterial circle method was studied. The results showed that the optimal process for the preparation of gelatin-chitosan-cinnamon essential oil natural coating solution was gelatin mass concentration of 6 mg/mL, chitosan mass concentration of 3 mg/mL, cinnamon essential oil mass concentration of 3 mg/mL, emulsifier mass concentration of 3 mg/mL, adjusting the pH of the solution to 4. 5, rotating speed of 800 r/min, stirring time of 30 min. The particle size of natural coating solution was (236. 54±18. 32) nm, and the encapsulation rate of cinnamon essential oil was (46. 78±2. 61)%. And the antibacterial effect of the natural coating solution treatment group was better than that of the chitosan and gelatin-chitosan groups. The addition of cinnamon essential oil could improve the inhibition effect of gelatin-chitosan coating solution.
The gelatin-chitosan-cinnamon essential oil natural coating solution was prepared by the self-assembly method, and the particle size of the natural coating solution and its encapsulation rate of cinnamon essential oil were used as indicators. On the basis of single factor test, orthogonal test was used to determine the optimal process for preparing natural coating solution. The antibacterial effect of the natural coating solution by the antibacterial circle method was studied. The results showed that the optimal process for the preparation of gelatin-chitosan-cinnamon essential oil natural coating solution was gelatin mass concentration of 6 mg/mL, chitosan mass concentration of 3 mg/mL, cinnamon essential oil mass concentration of 3 mg/mL, emulsifier mass concentration of 3 mg/mL, adjusting the pH of the solution to 4. 5, rotating speed of 800 r/min, stirring time of 30 min. The particle size of natural coating solution was (236. 54±18. 32) nm, and the encapsulation rate of cinnamon essential oil was (46. 78±2. 61)%. And the antibacterial effect of the natural coating solution treatment group was better than that of the chitosan and gelatin-chitosan groups. The addition of cinnamon essential oil could improve the inhibition effect of gelatin-chitosan coating solution.
2021, 36(4)
:18-28.
doi: 10.12187/2021.04.003
Abstract:
Aspergillus oryzae was used to prepare antioxidant peptides crude extract from Perilla seed meal by solid-state fermentation. The polypeptide content and 1, 1-diphenyl-2-trinitrophenylhydrazyl (DPPH) free radical scavenging rate were used as indicators, the single factor experiment was conducted on four factors that affect the fermentation time, fermentation temperature, inoculum amount, and liquid-to-material ratio of Aspergillus oryzae fermented Perilla seed meal, and the response surface was optimized on the basis of it. The results showed that the best process parameters for solid-state fermentation of Perilla seed meal by Aspergillus oryzae were fermentation time 48 h, fermentation temperature 28℃, inoculation amount 5.5% and liquid-to-material ratio 1:1. Under this technological condition, the polypeptide content of the solid-state fermentation product of Perilla seed meal was (58.75±1.12) mg/g, which was 2.66 times higher than that before fermentation; the DPPH free radical scavenging rate was (82.13±1.54)%, which was 0.23 times higher than that before fermentation; the IC50 of DPPH free radical was 0.17 mg/mL. The studies showed that Perilla seed meal could obtain biologically active peptides with high antioxidant capacity after solid-state fermentation of Aspergillus oryzae.
Aspergillus oryzae was used to prepare antioxidant peptides crude extract from Perilla seed meal by solid-state fermentation. The polypeptide content and 1, 1-diphenyl-2-trinitrophenylhydrazyl (DPPH) free radical scavenging rate were used as indicators, the single factor experiment was conducted on four factors that affect the fermentation time, fermentation temperature, inoculum amount, and liquid-to-material ratio of Aspergillus oryzae fermented Perilla seed meal, and the response surface was optimized on the basis of it. The results showed that the best process parameters for solid-state fermentation of Perilla seed meal by Aspergillus oryzae were fermentation time 48 h, fermentation temperature 28℃, inoculation amount 5.5% and liquid-to-material ratio 1:1. Under this technological condition, the polypeptide content of the solid-state fermentation product of Perilla seed meal was (58.75±1.12) mg/g, which was 2.66 times higher than that before fermentation; the DPPH free radical scavenging rate was (82.13±1.54)%, which was 0.23 times higher than that before fermentation; the IC50 of DPPH free radical was 0.17 mg/mL. The studies showed that Perilla seed meal could obtain biologically active peptides with high antioxidant capacity after solid-state fermentation of Aspergillus oryzae.
2021, 36(4)
:29-36.
doi: 10.12187/2021.04.004
Abstract:
In view of the research results of enriched product types and improved flavor characteristics and health care functions by applying probiotic fermentation technology in deep processing of fruit and vegetable juice, this paper summarized the influence of probiotic fermentation on physical and chemical properties of fruit and vegetable juice, the probiotic activity maintaining technology and probiotic function of fermented fruit and vegetable juice. It was pointed out that:probiotic fermentation could not only change the flavor and sensory quality of fruit and vegetable juice, but also changed the chemical components of organic acids and polyphenols in fruit and vegetable juice; the number of viable bacteria in probiotic fermented fruit and vegetable juice could be increased by adding auxiliary prebiotics, embedding microcapsules and optimizing fermentation conditions; fermented fruit and vegetable juice had probiotic functions such as raising gastrointestinal function, resisting oxidation, inhibiting bacteria and elevating type II diabetes. At present, the research on fermented fruit and vegetable juice was still in the laboratory research stage, and has not been put into the factory for mass production. In the future, in-depth research can be carried out on screening suitable fermentation strains, enhancing the survival rate of probiotics in fermented fruit and vegetable juice during storage, and studying the mechanism of the relationship between fermented fruit and vegetable juice and human digestive tract health and immune regulation, so as to further promote the functional researchdevelopment and industrial production of probiotic fermented fruit and vegetable juice.
In view of the research results of enriched product types and improved flavor characteristics and health care functions by applying probiotic fermentation technology in deep processing of fruit and vegetable juice, this paper summarized the influence of probiotic fermentation on physical and chemical properties of fruit and vegetable juice, the probiotic activity maintaining technology and probiotic function of fermented fruit and vegetable juice. It was pointed out that:probiotic fermentation could not only change the flavor and sensory quality of fruit and vegetable juice, but also changed the chemical components of organic acids and polyphenols in fruit and vegetable juice; the number of viable bacteria in probiotic fermented fruit and vegetable juice could be increased by adding auxiliary prebiotics, embedding microcapsules and optimizing fermentation conditions; fermented fruit and vegetable juice had probiotic functions such as raising gastrointestinal function, resisting oxidation, inhibiting bacteria and elevating type II diabetes. At present, the research on fermented fruit and vegetable juice was still in the laboratory research stage, and has not been put into the factory for mass production. In the future, in-depth research can be carried out on screening suitable fermentation strains, enhancing the survival rate of probiotics in fermented fruit and vegetable juice during storage, and studying the mechanism of the relationship between fermented fruit and vegetable juice and human digestive tract health and immune regulation, so as to further promote the functional researchdevelopment and industrial production of probiotic fermented fruit and vegetable juice.
2021, 36(4)
:37-44.
doi: 10.12187/2021.04.005
Abstract:
In order to investigate the effect of different ventilation distribution on organic acid release from mainstream smoke of slim cigarette, the slim cigarette samples with different filter ventilation and cigarette paper air permeability were rolled, and the organic acid in mainstream smoke of samples were analyzed by GC-MS, the prediction models of organic acids release based on both filter and paper ventilation rate were established. The results showed that were as follows:26 kinds of organic acids were detected. With the increase of filter ventilation rate or paper ventilation rate, the decrease rate of organic acids with smaller molecular weight was higher, while that with larger molecular weight was smaller, and the effect of paper ventilation rate on the release of organic acids in cigarette smoke was greater than that of filter ventilation rate. When the total ventilation rate(V) was constant, the release of organic acids in cigarette smoke with high filter ventilation rate and low paper ventilation rate was higher than that with low filter ventilation rate and high paper ventilation rate. The prediction accuracy of the model of organic acid release was high, and the results further proved that the cigarette organic acid release was higher with the combination of high filter ventilation rate and low paper ventilation rate.
In order to investigate the effect of different ventilation distribution on organic acid release from mainstream smoke of slim cigarette, the slim cigarette samples with different filter ventilation and cigarette paper air permeability were rolled, and the organic acid in mainstream smoke of samples were analyzed by GC-MS, the prediction models of organic acids release based on both filter and paper ventilation rate were established. The results showed that were as follows:26 kinds of organic acids were detected. With the increase of filter ventilation rate or paper ventilation rate, the decrease rate of organic acids with smaller molecular weight was higher, while that with larger molecular weight was smaller, and the effect of paper ventilation rate on the release of organic acids in cigarette smoke was greater than that of filter ventilation rate. When the total ventilation rate(V) was constant, the release of organic acids in cigarette smoke with high filter ventilation rate and low paper ventilation rate was higher than that with low filter ventilation rate and high paper ventilation rate. The prediction accuracy of the model of organic acid release was high, and the results further proved that the cigarette organic acid release was higher with the combination of high filter ventilation rate and low paper ventilation rate.
2021, 36(4)
:45-50.
doi: 10.12187/2021.04.006
Abstract:
In order to study the suitability about drying mode and fine tobacco processing, constant temperaturedrying mode, low temperature difference, medium temperature difference and high temperature difference sectional drying modes were used to dry cut tobacco respectively under the same other processing conditions, and the effects of different drying modes on cut tobacco structure, rolling quality and mainstream smoke components of slim cigarette were explored. The results showed that, compared with other drying modes, the structure proportion of cut tobacco dried by high temperature difference sectional drying mode was more suitable for slim cigarette processing. Under the conditions of constant temperature and high temperature difference sectional drying modes, the cigarette weight, drawing resistance, hardness and total ventilation rate of the slim cigarette were close to the design value, and physical quality indexes of the slim cigarette was relatively stable. Under the medium and high temperature difference sectional drying mode, the difference of tar, nicotine between the actual value and the design value were relatively low, and CO content was relatively low. In conclusion, high temperature difference sectional drying mode was suitable to slim cigarette processing.
In order to study the suitability about drying mode and fine tobacco processing, constant temperaturedrying mode, low temperature difference, medium temperature difference and high temperature difference sectional drying modes were used to dry cut tobacco respectively under the same other processing conditions, and the effects of different drying modes on cut tobacco structure, rolling quality and mainstream smoke components of slim cigarette were explored. The results showed that, compared with other drying modes, the structure proportion of cut tobacco dried by high temperature difference sectional drying mode was more suitable for slim cigarette processing. Under the conditions of constant temperature and high temperature difference sectional drying modes, the cigarette weight, drawing resistance, hardness and total ventilation rate of the slim cigarette were close to the design value, and physical quality indexes of the slim cigarette was relatively stable. Under the medium and high temperature difference sectional drying mode, the difference of tar, nicotine between the actual value and the design value were relatively low, and CO content was relatively low. In conclusion, high temperature difference sectional drying mode was suitable to slim cigarette processing.
2021, 36(4)
:51-57.
doi: 10.12187/2021.04.007
Abstract:
To make better use of discarded tobacco leaves and yield caramel spices for tobacco with obvious sweetness and rich fragrance, synergistic caramel products by extrusion method were developed on the basis of the caramel reactions. The single factor experiment was used to determine the preparation process of the synergistic caramel products. GC-MS detection and sensory evaluation were used to analyze the flavor components of the products and the applicability of discarded tobacco leaves for different producing areas the preparation process. The results show that the optimal mass fraction of glucose was 30%. The extrusion temperature of area Ⅲ 170℃ and area Ⅱ 150℃ was suitable. Compared with the control group, the aroma components content of the synergistic caramel products were increased by 4.4 folds, and the contents of tobacco terpenes fragrances were also significantly increased. The synergistic caramel products could improve the flavor richness, sweetness and taste of cigarette. The preparation method of the synergistic caramel products had certain applicability to the discarded tobacco leaves from different producing areas.
To make better use of discarded tobacco leaves and yield caramel spices for tobacco with obvious sweetness and rich fragrance, synergistic caramel products by extrusion method were developed on the basis of the caramel reactions. The single factor experiment was used to determine the preparation process of the synergistic caramel products. GC-MS detection and sensory evaluation were used to analyze the flavor components of the products and the applicability of discarded tobacco leaves for different producing areas the preparation process. The results show that the optimal mass fraction of glucose was 30%. The extrusion temperature of area Ⅲ 170℃ and area Ⅱ 150℃ was suitable. Compared with the control group, the aroma components content of the synergistic caramel products were increased by 4.4 folds, and the contents of tobacco terpenes fragrances were also significantly increased. The synergistic caramel products could improve the flavor richness, sweetness and taste of cigarette. The preparation method of the synergistic caramel products had certain applicability to the discarded tobacco leaves from different producing areas.
2021, 36(4)
:58-62.
doi: 10.12187/2021.04.008
Abstract:
A new rolling plate auto-cleaning equipment was designed based on the technology of rodless cylinder, to solve the problem that the rolling plate's surface of cigarette maker was difficult to clean. The device consists of copper brush, rodless cylinder, industrial camera, light source, blowing block and blowing rod, etc. It used the copper brush driven by the rodless cylinder to clean the paper, glue and other foreign matters on the rolling plate, and used the industrial camera to realize the intelligent detection of rolling plate cleanliness. The rolling plate auto-cleaning equipment was applied to ZJ116A cigarette maker for testing. The results showed that the rolling plate jam of the improved cigarette maker was 2.6 times per day less than that before the improvement decreased from 5.1 times/day to 2.5 times/day, the number of manual cleaning is also reduced by 3.03 times per dayalso decreased from 4.03 times/day to 1 times/day. The rolling plate auto-cleaning equipment could effectively improve the operation rate of the cigarette maker.
A new rolling plate auto-cleaning equipment was designed based on the technology of rodless cylinder, to solve the problem that the rolling plate's surface of cigarette maker was difficult to clean. The device consists of copper brush, rodless cylinder, industrial camera, light source, blowing block and blowing rod, etc. It used the copper brush driven by the rodless cylinder to clean the paper, glue and other foreign matters on the rolling plate, and used the industrial camera to realize the intelligent detection of rolling plate cleanliness. The rolling plate auto-cleaning equipment was applied to ZJ116A cigarette maker for testing. The results showed that the rolling plate jam of the improved cigarette maker was 2.6 times per day less than that before the improvement decreased from 5.1 times/day to 2.5 times/day, the number of manual cleaning is also reduced by 3.03 times per dayalso decreased from 4.03 times/day to 1 times/day. The rolling plate auto-cleaning equipment could effectively improve the operation rate of the cigarette maker.
2021, 36(4)
:63-77.
doi: 10.12187/2021.04.009
Abstract:
Cigarette butts were the final byproduct after cigarette smoking, the resource utilization of cigarette butts was of great significance for reducing environmental pollution and promoting effective utilization of resources simultaneously. Based on the literature review of cigarette butts resource utilization, it was pointed out that in terms of construction materials, lightweight clay bricks, asphalt concrete and sound/wave-absorbed materials were the main products of cigarette butts. The processing capacity of cigarette butts in this field was relatively large, and the products had the characteristics of light weight and heat insulation. In terms of carbon materials, adsorbent and the electrochemical materials were the mian products of cigarette butts, and the preparation of the later material was an important way for the high-value utilization of cigarette butts in the future. The chemical components absorbed by cigarette butts could be used to prepare products, mainly including metal corrosion inhibitors and insecticides for mosquitoes. The research on extracting chemical raw materials from cigarette butts was relatively less. The oil-water separation materials were prepared by the cellulose acetate of cigarette butts and the organosilane/polydopamine-modified products. The cellulose films or nanocrystals prepared from cellulose acetate also featured an excellent water purification performance. In the future, we could improve the infrastructure such as smoking area and smoking control area to facilitate the effective collection of cigarette butts, conduct comprehensive evaluation from the three aspects of "cost-environment-benefit" to shorten the transformation cycle between technology and industrialization, and carry out in-depth research from the development of degradable filter materials and reusable filters, so as to promote the industrialization of resource utilization of cigarette butts.
Cigarette butts were the final byproduct after cigarette smoking, the resource utilization of cigarette butts was of great significance for reducing environmental pollution and promoting effective utilization of resources simultaneously. Based on the literature review of cigarette butts resource utilization, it was pointed out that in terms of construction materials, lightweight clay bricks, asphalt concrete and sound/wave-absorbed materials were the main products of cigarette butts. The processing capacity of cigarette butts in this field was relatively large, and the products had the characteristics of light weight and heat insulation. In terms of carbon materials, adsorbent and the electrochemical materials were the mian products of cigarette butts, and the preparation of the later material was an important way for the high-value utilization of cigarette butts in the future. The chemical components absorbed by cigarette butts could be used to prepare products, mainly including metal corrosion inhibitors and insecticides for mosquitoes. The research on extracting chemical raw materials from cigarette butts was relatively less. The oil-water separation materials were prepared by the cellulose acetate of cigarette butts and the organosilane/polydopamine-modified products. The cellulose films or nanocrystals prepared from cellulose acetate also featured an excellent water purification performance. In the future, we could improve the infrastructure such as smoking area and smoking control area to facilitate the effective collection of cigarette butts, conduct comprehensive evaluation from the three aspects of "cost-environment-benefit" to shorten the transformation cycle between technology and industrialization, and carry out in-depth research from the development of degradable filter materials and reusable filters, so as to promote the industrialization of resource utilization of cigarette butts.
2021, 36(4)
:78-85.
doi: 10.12187/2021.04.010
Abstract:
Using catalpol and propionyl anhydride as raw materials, pyridine as solvent and acid binding agent, catalpol perpropionyl product (CP-6) was synthesised by microwave-assisted method. The synthesis conditions were optimized by orthogonal test, and the neuroprotective activity was initially screened by the colorimetric method of the tetramethylazolyzol salt trace enzyme reaction. The test results showed that when the molar ratio of propionic anhydride to catalpol was 18:1, the reaction temperature in the microwave reactor was 80℃, the reaction time was 6 h, and the mass concentration of catalpol in pyridine was 25 g/L, the relative content of CP-6 in the reaction system could reach 98. 51%. MTT method was used to screen the neuroprotec tive activity of CP-6, and the results showed that CP-6 had neuroprotective effect and may be a potential neu roprotective agent.
Using catalpol and propionyl anhydride as raw materials, pyridine as solvent and acid binding agent, catalpol perpropionyl product (CP-6) was synthesised by microwave-assisted method. The synthesis conditions were optimized by orthogonal test, and the neuroprotective activity was initially screened by the colorimetric method of the tetramethylazolyzol salt trace enzyme reaction. The test results showed that when the molar ratio of propionic anhydride to catalpol was 18:1, the reaction temperature in the microwave reactor was 80℃, the reaction time was 6 h, and the mass concentration of catalpol in pyridine was 25 g/L, the relative content of CP-6 in the reaction system could reach 98. 51%. MTT method was used to screen the neuroprotec tive activity of CP-6, and the results showed that CP-6 had neuroprotective effect and may be a potential neu roprotective agent.
2021, 36(4)
:86-96,104.
doi: 10.12187/2021.04.011
Abstract:
The thermal simulation testing machine was used to conduct axisymmetric isothermal hot compression experiments on 6063-T5 aluminum alloy. The influence of thermal deformation parameters on the true flow stress was analyzed, and the adaptive coefficient Arrhenius constitutive model and dislocation density growth model were established.The influence of process parameters on the hot deformation behavior of 6063-T5 aluminum alloy was investigated by drawing the hot working diagram. The results showed that, with the increase of temperature, the true stress showed a step-down trend, and the softening effect of the material became more and more obvious. With the increase of strain rate, the true stress increased slowly, and the hardening effect became more and more obvious. The Arrhenius constitutive model which was constructed by using the determination coefficient as the evaluation criterion and the dislocation density growth model can accurately describe the influence of hot deformation parameters on the hot deformation behavior of 6063-T5 aluminum alloy. The hot processing map showed that the optimum deformation temperature and strain rate ranges for the 6063-T5 aluminum alloy were 350~525℃ and 0.01~1 s-1 respectively.
The thermal simulation testing machine was used to conduct axisymmetric isothermal hot compression experiments on 6063-T5 aluminum alloy. The influence of thermal deformation parameters on the true flow stress was analyzed, and the adaptive coefficient Arrhenius constitutive model and dislocation density growth model were established.The influence of process parameters on the hot deformation behavior of 6063-T5 aluminum alloy was investigated by drawing the hot working diagram. The results showed that, with the increase of temperature, the true stress showed a step-down trend, and the softening effect of the material became more and more obvious. With the increase of strain rate, the true stress increased slowly, and the hardening effect became more and more obvious. The Arrhenius constitutive model which was constructed by using the determination coefficient as the evaluation criterion and the dislocation density growth model can accurately describe the influence of hot deformation parameters on the hot deformation behavior of 6063-T5 aluminum alloy. The hot processing map showed that the optimum deformation temperature and strain rate ranges for the 6063-T5 aluminum alloy were 350~525℃ and 0.01~1 s-1 respectively.
2021, 36(4)
:97-104.
doi: 10.12187/2021.04.012
Abstract:
By analyzing the characteristics of the friction and wear process of bulk amorphous alloys, the main influencing factors of its friction and wear performances were summarized.The research status of the friction and wear performances of bulk amorphous alloys were also described from three aspects:the comparison of the friction and wear performances of amorphous alloys and the corresponding crystalline alloys, the effect of heat treatment and friction-induced crystallization structure on the friction and wear performances. It was pointed out that the main factors affecting the friction and wear performances of bulk amorphous alloys were heat transfer factors, counter-face materials and friction conditions, and the different influencing factors were interrelated and affected each other.The thermal properties of the counter-face materials determined export rate of the friction heat, and affected the friction process by affecting the friction surface temperature.When the friction conditions change, the stability of amorphous alloy materials was changed and the amount of wear increased or decreased sharply, thereby affecting its friction properties.Due to the characteristics of the structure and the friction and wear process of amorphous alloys, there were contradictory conclusions in research of the comparative study on the friction properties of amorphous alloys and corresponding crystalline materials, the effect of heat treatment and friction-induced crystallization structure on the friction properties of bulk amorphous alloy materials.It is necessary to further study the relationship between the structure of amorphous alloys and its tribological behaviors, explore the wear mechanism and its transformation laws.Then the methods and approach of improving the wear resistance of amorphous alloys were obtained.
By analyzing the characteristics of the friction and wear process of bulk amorphous alloys, the main influencing factors of its friction and wear performances were summarized.The research status of the friction and wear performances of bulk amorphous alloys were also described from three aspects:the comparison of the friction and wear performances of amorphous alloys and the corresponding crystalline alloys, the effect of heat treatment and friction-induced crystallization structure on the friction and wear performances. It was pointed out that the main factors affecting the friction and wear performances of bulk amorphous alloys were heat transfer factors, counter-face materials and friction conditions, and the different influencing factors were interrelated and affected each other.The thermal properties of the counter-face materials determined export rate of the friction heat, and affected the friction process by affecting the friction surface temperature.When the friction conditions change, the stability of amorphous alloy materials was changed and the amount of wear increased or decreased sharply, thereby affecting its friction properties.Due to the characteristics of the structure and the friction and wear process of amorphous alloys, there were contradictory conclusions in research of the comparative study on the friction properties of amorphous alloys and corresponding crystalline materials, the effect of heat treatment and friction-induced crystallization structure on the friction properties of bulk amorphous alloy materials.It is necessary to further study the relationship between the structure of amorphous alloys and its tribological behaviors, explore the wear mechanism and its transformation laws.Then the methods and approach of improving the wear resistance of amorphous alloys were obtained.
2021, 36(4)
:105-111.
doi: 10.12187/2021.04.013
Abstract:
Aiming at the problems of the insufficient sensitivity and poor measurement accuracy due to the stable flow rate and rate changes and other factors, taking ultrasonic thermal energy flowmeter with time difference method as the research object, an adaptive compensation algorithm for thermal energy flowmeter was proposed. The nonlinear relationship between heat and comprehensive compensation coefficient was studied, a mathematical model of error compensation was established, and then a weighted Lagrange fitting correction algorithm was proposed to realize adaptive correction of comprehensive coefficients. The experimental results showed that, compared with the traditional algorithms, the proposed algorithm could improve the instrument detection accuracy and reduce the measurement error which had high engineering application value.
Aiming at the problems of the insufficient sensitivity and poor measurement accuracy due to the stable flow rate and rate changes and other factors, taking ultrasonic thermal energy flowmeter with time difference method as the research object, an adaptive compensation algorithm for thermal energy flowmeter was proposed. The nonlinear relationship between heat and comprehensive compensation coefficient was studied, a mathematical model of error compensation was established, and then a weighted Lagrange fitting correction algorithm was proposed to realize adaptive correction of comprehensive coefficients. The experimental results showed that, compared with the traditional algorithms, the proposed algorithm could improve the instrument detection accuracy and reduce the measurement error which had high engineering application value.
2021, 36(4)
:112-117.
doi: 10.12187/2021.04.014
Abstract:
Multi-channel frequency hopping (FH) communication systems are often disturbed by channel hopping, which results in channel anomalies.In order to solve this problem, an adaptive feedback channel modulation method was designed to identify the abnormal hopping of a multi-channel FH communication system. Firstly, the channel model of the multi-channel FH communication system was constructed, and the output conversion control was developed by combining the space channel equalization method, and the carrier modulation and beam output were adjusted by the decision feedback regulation method, then the channel feedback equalization control model of the multi-channel FH communication system was established. Based on this, the adaptive parameter adjustment method was used to carry out the equalization design of the multi-channel FH communication system and the optimized parameter identification, the channel output gain was improved through spread spectrum processing, and then the abnormal hopping position information was identified according to the extracted results of channel difference feature points. The simulation results showed that this method was more accurate in identifying the abnormal hopping of multi-channel FH communication system, and the communication channel equalization was better after the application of this method.
Multi-channel frequency hopping (FH) communication systems are often disturbed by channel hopping, which results in channel anomalies.In order to solve this problem, an adaptive feedback channel modulation method was designed to identify the abnormal hopping of a multi-channel FH communication system. Firstly, the channel model of the multi-channel FH communication system was constructed, and the output conversion control was developed by combining the space channel equalization method, and the carrier modulation and beam output were adjusted by the decision feedback regulation method, then the channel feedback equalization control model of the multi-channel FH communication system was established. Based on this, the adaptive parameter adjustment method was used to carry out the equalization design of the multi-channel FH communication system and the optimized parameter identification, the channel output gain was improved through spread spectrum processing, and then the abnormal hopping position information was identified according to the extracted results of channel difference feature points. The simulation results showed that this method was more accurate in identifying the abnormal hopping of multi-channel FH communication system, and the communication channel equalization was better after the application of this method.
2021, 36(4)
:118-124.
doi: 10.12187/2021.04.015
Abstract:
The Aiming at the problems of large number of bottom events and component polymorphism in the current reliability analysis method of the on-load tap-changer is significantly important for the stability of the transformer and even electrical power system. In this paper, the reliability was evaluated by using the multi-state multi-valued decision diagram (MMDD). First, the reliability evaluation model was built based on the induction and classification of the fault modes of the on-load tap-changer. Second, the of the system reliability is qualitatively andwas quantitatively analyzed by using the multi-state decision graphMMDD. Finally, the reliability of each fault condition of the tap-changer was evaluated under the probability importance of each component. An evaluation Example analysis results showed that the MMDD had the advantages of investigation, deduction, calculation and explanation of the system faults. Further, and the relationship between fault term and system reliability could be obtained.
The Aiming at the problems of large number of bottom events and component polymorphism in the current reliability analysis method of the on-load tap-changer is significantly important for the stability of the transformer and even electrical power system. In this paper, the reliability was evaluated by using the multi-state multi-valued decision diagram (MMDD). First, the reliability evaluation model was built based on the induction and classification of the fault modes of the on-load tap-changer. Second, the of the system reliability is qualitatively andwas quantitatively analyzed by using the multi-state decision graphMMDD. Finally, the reliability of each fault condition of the tap-changer was evaluated under the probability importance of each component. An evaluation Example analysis results showed that the MMDD had the advantages of investigation, deduction, calculation and explanation of the system faults. Further, and the relationship between fault term and system reliability could be obtained.
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
(086)0371-86608633
