2021 Vol. 36, No. 2
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2021, 36(2)
:1-9.
doi: 10.12187/2021.02.001
Abstract:
The key process of industrial production of Guangdong steamed chicken was optimized by single factor test and orthogonal test with Guangdong native chicken as raw material.The sensory quantitative descriptive test and electronic nose were used to compare the preparation of Guangdong steamed chicken and the commercial Guangdong steamed chicken under the optimal technological conditions.The results showed that the key technological conditions for industrial production of Guangdong steamed chicken were as follows:spice content 0.5%,pickling time 5 h,steaming time 20 min.The comprehensive sensory score of Guangdong steamed chicken was 96.0 under the optimal conditions.Compared with the commercial Guangdong steamed chicken,the Guangdong steamed chicken prepared by the best technology had similar characteristic flavor and aroma,but the methyl volatile components were higher,and the flavor and texture were significantly improved.In addition,the aroma,taste and saltiness were more uniform and stable.
The key process of industrial production of Guangdong steamed chicken was optimized by single factor test and orthogonal test with Guangdong native chicken as raw material.The sensory quantitative descriptive test and electronic nose were used to compare the preparation of Guangdong steamed chicken and the commercial Guangdong steamed chicken under the optimal technological conditions.The results showed that the key technological conditions for industrial production of Guangdong steamed chicken were as follows:spice content 0.5%,pickling time 5 h,steaming time 20 min.The comprehensive sensory score of Guangdong steamed chicken was 96.0 under the optimal conditions.Compared with the commercial Guangdong steamed chicken,the Guangdong steamed chicken prepared by the best technology had similar characteristic flavor and aroma,but the methyl volatile components were higher,and the flavor and texture were significantly improved.In addition,the aroma,taste and saltiness were more uniform and stable.
2021, 36(2)
:10-16.
doi: 10.12187/2021.02.002
Abstract:
By simulating the processing of roasted chicken wing roots,the experimental environment,thawing water,contact surface,and meat products were sampled and tested to study the source of pathogenic microorganisms and the law of bacterial phase change during the processing of roasted chicken wing roots.The results showed that during the processing of roasted chicken wing roots,the highest number of colonies in the experimental ambient was in the thawing zone,which was 165 CFU/dish,followed by the pretreatment zone,which was 105 CFU/dish. The number of microorganisms in the thawing water showed an overall upward trend with the thawing process. The total number of bacterial colonies in the hands of the experimenters in the pretreatment area was higher than that of the experimenters in the vacuum packaging area,and the hands of the experimenters in the pretreatment area had a certain amount of E. coli and fungi. The total number of colonies on the contact surface of the scissors and the basket of the thawing tank and the pretreatment area was large,and the total number of colonies on the contact surface of the packaging basket reached the highest value of 4.1 CFU/cm2. As the processing progresses,the number of microorganisms in the roasted chicken wing roots increased first and then decreased. In the process of thawing,pretreatment and tumbling,the total number of colonies in the semi-finished product was significantly higher,and the number of microorganisms decreased significantly after roasting. By taking measures such as controlling the sanitary condition of raw materials,disinfecting the experimental environment in real time,strictly abiding by operating regulations,shortening the thawing time,and reducing secondary pollution,the pollution of pathogenic microorganisms could be effectively controlled and the quality of products could be guaranteed.
By simulating the processing of roasted chicken wing roots,the experimental environment,thawing water,contact surface,and meat products were sampled and tested to study the source of pathogenic microorganisms and the law of bacterial phase change during the processing of roasted chicken wing roots.The results showed that during the processing of roasted chicken wing roots,the highest number of colonies in the experimental ambient was in the thawing zone,which was 165 CFU/dish,followed by the pretreatment zone,which was 105 CFU/dish. The number of microorganisms in the thawing water showed an overall upward trend with the thawing process. The total number of bacterial colonies in the hands of the experimenters in the pretreatment area was higher than that of the experimenters in the vacuum packaging area,and the hands of the experimenters in the pretreatment area had a certain amount of E. coli and fungi. The total number of colonies on the contact surface of the scissors and the basket of the thawing tank and the pretreatment area was large,and the total number of colonies on the contact surface of the packaging basket reached the highest value of 4.1 CFU/cm2. As the processing progresses,the number of microorganisms in the roasted chicken wing roots increased first and then decreased. In the process of thawing,pretreatment and tumbling,the total number of colonies in the semi-finished product was significantly higher,and the number of microorganisms decreased significantly after roasting. By taking measures such as controlling the sanitary condition of raw materials,disinfecting the experimental environment in real time,strictly abiding by operating regulations,shortening the thawing time,and reducing secondary pollution,the pollution of pathogenic microorganisms could be effectively controlled and the quality of products could be guaranteed.
2021, 36(2)
:17-24.
doi: 10.12187/2021.02.003
Abstract:
The sour chicken sealed anaerobic fermented by traditional methods in Qianyu and Xiangxi regions was studied,with the fresh chicken as the control.They pH value,color,texture,tenderness and volatile flavor compounds were determined and microbial isolation,identification and sensory evaluation were conducted.The results showed that compared with the fresh chicken,the quality of sour chicken has changed significantly.The pH value,L* value and elasticity of the sour chicken reduced significantly,the b* value,hardness,cohesion chewiness and tenderness increased significantly,and the a* value did not change significantly.Volatile flavor compounds increased from 36 kinds (fresh chicken) to 55 kinds,and among them,the mass fraction of acidic flavor substances that directly contribute to the flavor of sour chicken increased from 6.03% to 29.00%.The amount of colony and quantity of lactic acid bacteria increased significantly.The sensory scores of the three aspects of the texture,smell,and taste of the sour chicken meat significantly increased,and the color was better than that of fresh chicken,but the difference was not significant.
The sour chicken sealed anaerobic fermented by traditional methods in Qianyu and Xiangxi regions was studied,with the fresh chicken as the control.They pH value,color,texture,tenderness and volatile flavor compounds were determined and microbial isolation,identification and sensory evaluation were conducted.The results showed that compared with the fresh chicken,the quality of sour chicken has changed significantly.The pH value,L* value and elasticity of the sour chicken reduced significantly,the b* value,hardness,cohesion chewiness and tenderness increased significantly,and the a* value did not change significantly.Volatile flavor compounds increased from 36 kinds (fresh chicken) to 55 kinds,and among them,the mass fraction of acidic flavor substances that directly contribute to the flavor of sour chicken increased from 6.03% to 29.00%.The amount of colony and quantity of lactic acid bacteria increased significantly.The sensory scores of the three aspects of the texture,smell,and taste of the sour chicken meat significantly increased,and the color was better than that of fresh chicken,but the difference was not significant.
2021, 36(2)
:25-33.
doi: 10.12187/2021.02.004
Abstract:
On the basis of a brief description of immobilized enzymes and their characteristics,the relevant application research of immobilized enzymes in the food industry (food processing and storage,food additive production,bioactive peptide preparation and food testing) was reviewed.It was pointed out that the application of immobilized enzymes in the food industry could not only increase the decomposition rate,increase the output of industrial production,and reduce production costs; but also help to retain the original flavor of the product and increase its functionality.Biosensors based on immobilized enzymes had the advantages of fast,high efficiency and easy operation.In the future,further research could be done on seeking new immobilization technologies and immobilized carriers,optimizing immobilized pre-separation technologies,and preparing new immobilized enzymes capable of multi-enzyme reactions to promote the application of immobilized enzymes in the food industry.
On the basis of a brief description of immobilized enzymes and their characteristics,the relevant application research of immobilized enzymes in the food industry (food processing and storage,food additive production,bioactive peptide preparation and food testing) was reviewed.It was pointed out that the application of immobilized enzymes in the food industry could not only increase the decomposition rate,increase the output of industrial production,and reduce production costs; but also help to retain the original flavor of the product and increase its functionality.Biosensors based on immobilized enzymes had the advantages of fast,high efficiency and easy operation.In the future,further research could be done on seeking new immobilization technologies and immobilized carriers,optimizing immobilized pre-separation technologies,and preparing new immobilized enzymes capable of multi-enzyme reactions to promote the application of immobilized enzymes in the food industry.
2021, 36(2)
:34-42.
doi: 10.12187/2021.02.005
Abstract:
The volatile chemical components of tobacco flavor were prepared by simultaneous distillation extraction and analyzed using gas chromatography-mass spectrometry.The aroma-active violates were determined by means of gas chromatography-mass spectrometry-olfactometry combined with aroma extraction dilution analysis,and the important odorants were further screened out according to quantitative study and odor activity values.Aroma recombination and omission experiments identified the key odorants of the tobacco flavor.The results exhibited that simultaneous distillation extraction of tobacco flavor included 54 kinds of volatile compounds,including 22 aroma-active compounds,and 17 odorants were screened out as the predominant odorants according to flavor dilution factors and odor activity values.β-damascarone,linalool,ethyl maltol,linalyl acetate,neryl acetate,myrcene,nerol,geranyl acetate,D-limonene,and benzyl alcohol were confirmed as the key odorants of tobacco flavor.
The volatile chemical components of tobacco flavor were prepared by simultaneous distillation extraction and analyzed using gas chromatography-mass spectrometry.The aroma-active violates were determined by means of gas chromatography-mass spectrometry-olfactometry combined with aroma extraction dilution analysis,and the important odorants were further screened out according to quantitative study and odor activity values.Aroma recombination and omission experiments identified the key odorants of the tobacco flavor.The results exhibited that simultaneous distillation extraction of tobacco flavor included 54 kinds of volatile compounds,including 22 aroma-active compounds,and 17 odorants were screened out as the predominant odorants according to flavor dilution factors and odor activity values.β-damascarone,linalool,ethyl maltol,linalyl acetate,neryl acetate,myrcene,nerol,geranyl acetate,D-limonene,and benzyl alcohol were confirmed as the key odorants of tobacco flavor.
2021, 36(2)
:43-48.
doi: 10.12187/2021.02.006
Abstract:
In order to realize the digital design of tobacco stem formula,18 samples of upper,middle and lower tobacco stems from 6 main producing areas (Chuxiong,Nanping,Chenzhou,Chongqing,Bijie and Pingdingshan) in China were selected as the research objects. Based on the standardized score comprehensive evaluatition,a quantitative evaluation method for usability of tobacco stem raw materials was established from five factors including luster of tobacco stem,filling value,sensory quality,tar release per gram of tobacco stem and comprehensive hazard index of smoke,combined with the demand of different grades of cigarettes for tobacco stem raw materials. The results showed that the tobacco stem raw materials optimized by the standard score evaluation method were made into stem shreds,and the relevant indicators were consistent with the design goals of the stem shred formula,indicating that the method was objective and simple,and it could be used as a quantitative method for comprehensive evaluation of tobacco stem usability.
In order to realize the digital design of tobacco stem formula,18 samples of upper,middle and lower tobacco stems from 6 main producing areas (Chuxiong,Nanping,Chenzhou,Chongqing,Bijie and Pingdingshan) in China were selected as the research objects. Based on the standardized score comprehensive evaluatition,a quantitative evaluation method for usability of tobacco stem raw materials was established from five factors including luster of tobacco stem,filling value,sensory quality,tar release per gram of tobacco stem and comprehensive hazard index of smoke,combined with the demand of different grades of cigarettes for tobacco stem raw materials. The results showed that the tobacco stem raw materials optimized by the standard score evaluation method were made into stem shreds,and the relevant indicators were consistent with the design goals of the stem shred formula,indicating that the method was objective and simple,and it could be used as a quantitative method for comprehensive evaluation of tobacco stem usability.
2021, 36(2)
:49-54.
doi: 10.12187/2021.02.007
Abstract:
In order to explore the effects of slim cigarette material parameters on benzo[a]pyrene (B[a]P) delivery in mainstream smoke,the uniform design method was used to design the test plan,and the stepwise regression method was used to establish the regression equations between the release of B[a]P and slim cigarette auxiliary material factors,including cigarette paper permeability(X1),tipping paper permeability(X2),plug wrapper permeability(X3),tow specification in the filter(X4).The optimized auxiliary material parameters were verified.The results showed that the sequence of every factor on the B[a]P yield was X3 > X4 > X2 > X1,and all the factors had negative effects on the release of B[a]P.The order of the influence of each factor or interaction of factors on the target value was as follows:X2X3 > X1X4 > X32 > X4,the positive correlation with the delivery of B[a]P were X32 and X4,and the negative correlation with the delivery of B[a]P were X2X3 and X1X4.The optimized auxiliary material combination for low B[a]P delivery were 100 CU(X1),800 CU (X2),26 000 CU (X3),6.0Y/17 000(X4).Compared with the lowest B[a]P in the experimental group,the predicative value of the B[a]P delivery in mainstream smoke of slim cigarette decreased by 39.3%.
In order to explore the effects of slim cigarette material parameters on benzo[a]pyrene (B[a]P) delivery in mainstream smoke,the uniform design method was used to design the test plan,and the stepwise regression method was used to establish the regression equations between the release of B[a]P and slim cigarette auxiliary material factors,including cigarette paper permeability(X1),tipping paper permeability(X2),plug wrapper permeability(X3),tow specification in the filter(X4).The optimized auxiliary material parameters were verified.The results showed that the sequence of every factor on the B[a]P yield was X3 > X4 > X2 > X1,and all the factors had negative effects on the release of B[a]P.The order of the influence of each factor or interaction of factors on the target value was as follows:X2X3 > X1X4 > X32 > X4,the positive correlation with the delivery of B[a]P were X32 and X4,and the negative correlation with the delivery of B[a]P were X2X3 and X1X4.The optimized auxiliary material combination for low B[a]P delivery were 100 CU(X1),800 CU (X2),26 000 CU (X3),6.0Y/17 000(X4).Compared with the lowest B[a]P in the experimental group,the predicative value of the B[a]P delivery in mainstream smoke of slim cigarette decreased by 39.3%.
2021, 36(2)
:55-63.
doi: 10.12187/2021.02.008
Abstract:
Using ammonium tetrathiomolybdate and hydrazine hydrate as raw materials,the sulfur-vacancy containing MoS2 was synthesized by simple hydrothermal synthesis combined with subsequent ethanol solvothermal treatment,and its hydrogen evolution reaction (HER) performance was investigated.The electrochemical performance was calculated by first principle density functional theory.The results showed that sulfur-vacancy had obvious effect on HER performance of MoS2.The Tafel slope of the sample Eth24h-MoS2 obtained by ethanol solvothermal treatment for 24 h was 69 mV/dec and the overpotential was 237 mV at current density of 10 mA/cm2,which was significantly lower than that of the original MoS2,and had good electrochemical stability.With the increase of sulfur-vacancy density,the band gap of MoS2 decreased and its conductivity improved.The hydrogen adsorption free energy ΔGH of sulfur-vacancy position and sulfur-vacancy free position decreased rapidly.The closer the hydrogen adsorption site was to the sulfur-vacancy position,the smaller the ΔGH value was.
Using ammonium tetrathiomolybdate and hydrazine hydrate as raw materials,the sulfur-vacancy containing MoS2 was synthesized by simple hydrothermal synthesis combined with subsequent ethanol solvothermal treatment,and its hydrogen evolution reaction (HER) performance was investigated.The electrochemical performance was calculated by first principle density functional theory.The results showed that sulfur-vacancy had obvious effect on HER performance of MoS2.The Tafel slope of the sample Eth24h-MoS2 obtained by ethanol solvothermal treatment for 24 h was 69 mV/dec and the overpotential was 237 mV at current density of 10 mA/cm2,which was significantly lower than that of the original MoS2,and had good electrochemical stability.With the increase of sulfur-vacancy density,the band gap of MoS2 decreased and its conductivity improved.The hydrogen adsorption free energy ΔGH of sulfur-vacancy position and sulfur-vacancy free position decreased rapidly.The closer the hydrogen adsorption site was to the sulfur-vacancy position,the smaller the ΔGH value was.
2021, 36(2)
:64-73.
doi: 10.12187/2021.02.009
Abstract:
polymethyl methacrylate-methacrylic acid/silica (Poly(MMA/MAA)/SiO2,that is,PMMS),carboxymethyl chitosan (CMCS),acrylamide (AAm) were used as raw materials,EDC/NHS as catalysis,the CMCS-PMMS/PAAm composite hydrogel was prepared by pH adjustment,free radical polymerization.The rheological properties,mechanical properties,swelling properties,electrical conductivity and biocompatibility of the hydrogels were studied.The results showed that the pH value had a great influence on the rheological properties of the composite hydrogel.The storage modulus (G') decreased first and then increased.When the pH value was 6,the G' maximum was 9200 Pa; Hydrogels with low pH were stiff,and the ones with high pH were soft and tough.When the pH value was 9 or 10,the composite hydrogel could maintain a good shape under a large compressive strain. It had good tensile properties and cyclic compressibility.The composite hydrogel also had good swelling properties,and even after water absorption reached the swelling equilibrium,it could still maintain the deformation recovery ability (the equilibrium swelling rate in pure water could reach 860%).In addition,the hydrogel had good conductivity,the highest conductivity could reach 2.98×10-4 S/cm; and it had good anti-hemolysis performance and cell compatibility.The hemolysis rate of all composite hydrogel samples was less than 5%,and the cytoactive was more than 75%.
polymethyl methacrylate-methacrylic acid/silica (Poly(MMA/MAA)/SiO2,that is,PMMS),carboxymethyl chitosan (CMCS),acrylamide (AAm) were used as raw materials,EDC/NHS as catalysis,the CMCS-PMMS/PAAm composite hydrogel was prepared by pH adjustment,free radical polymerization.The rheological properties,mechanical properties,swelling properties,electrical conductivity and biocompatibility of the hydrogels were studied.The results showed that the pH value had a great influence on the rheological properties of the composite hydrogel.The storage modulus (G') decreased first and then increased.When the pH value was 6,the G' maximum was 9200 Pa; Hydrogels with low pH were stiff,and the ones with high pH were soft and tough.When the pH value was 9 or 10,the composite hydrogel could maintain a good shape under a large compressive strain. It had good tensile properties and cyclic compressibility.The composite hydrogel also had good swelling properties,and even after water absorption reached the swelling equilibrium,it could still maintain the deformation recovery ability (the equilibrium swelling rate in pure water could reach 860%).In addition,the hydrogel had good conductivity,the highest conductivity could reach 2.98×10-4 S/cm; and it had good anti-hemolysis performance and cell compatibility.The hemolysis rate of all composite hydrogel samples was less than 5%,and the cytoactive was more than 75%.
2021, 36(2)
:74-82.
doi: 10.12187/2021.02.010
Abstract:
The pyrolysis gas release behavior and pyrolysis kinetics characteristics of bamboo powder were investigated by using TG-FTIR instrument and distributed activation energy model (DAEM) under a wide range of heating rates (20 ℃/min,50 ℃/min,and 100 ℃/min).The results showed that the pyrolysis process of bamboo powder experienced three stages,that was,the preheating drying stage,fast degradation stage and carbonization stage.The pyrolysis weight loss curve and differential weight loss curve shifted to the high temperature side with the increase of heating rate.The maximum of mass loss rate also increased as the heating rate increased,which was conducive to the full release of volatile components.The prominent volatile components released during the pyrolysis process of bamboo were CO2,aldehydes,ketones,organic acids and aromatic hydrocarbon,alkanes,phenols,etc.The activation energies fluctuated obviously with the conversion degree.The activation energies increased gradually with conversion degree during 0.10 and 0.25.During 0.25 and 0.80,the decomposition of cellulose/lignin and secondary decomposition of coke occurred,and the activation energies ranged from 219.7 kJ/mol to 268.8 kJ/mol.
The pyrolysis gas release behavior and pyrolysis kinetics characteristics of bamboo powder were investigated by using TG-FTIR instrument and distributed activation energy model (DAEM) under a wide range of heating rates (20 ℃/min,50 ℃/min,and 100 ℃/min).The results showed that the pyrolysis process of bamboo powder experienced three stages,that was,the preheating drying stage,fast degradation stage and carbonization stage.The pyrolysis weight loss curve and differential weight loss curve shifted to the high temperature side with the increase of heating rate.The maximum of mass loss rate also increased as the heating rate increased,which was conducive to the full release of volatile components.The prominent volatile components released during the pyrolysis process of bamboo were CO2,aldehydes,ketones,organic acids and aromatic hydrocarbon,alkanes,phenols,etc.The activation energies fluctuated obviously with the conversion degree.The activation energies increased gradually with conversion degree during 0.10 and 0.25.During 0.25 and 0.80,the decomposition of cellulose/lignin and secondary decomposition of coke occurred,and the activation energies ranged from 219.7 kJ/mol to 268.8 kJ/mol.
2021, 36(2)
:83-91.
doi: 10.12187/2021.02.011
Abstract:
Four resonance compensation topologies equivalent circuit models for magnetic field coupling resonance wireless power transfer system (primary side series and secondary side series type,primary side series secondary side parallel type,primary side parallel secondary side series type and primary side parallel secondary side parallel type) was constructed. The efficiency characteristics of magnetic field coupling resonance wireless power transfer systemwasanalyzed. The influence of coupling coefficient and quality factor on system efficiency was studied. The simulation results showed that the secondary side resonance compensation topology had a greater impact on the system efficiency,and the system efficiency was more sensitive to changes in the coupling coefficient and quality factors.Compared with the secondary side using the series compensation topology,the system had a wider range of high transfer efficiency when the secondary side used the parallel compensation topology. The experimental results verified the correctness of the simulation results.
Four resonance compensation topologies equivalent circuit models for magnetic field coupling resonance wireless power transfer system (primary side series and secondary side series type,primary side series secondary side parallel type,primary side parallel secondary side series type and primary side parallel secondary side parallel type) was constructed. The efficiency characteristics of magnetic field coupling resonance wireless power transfer systemwasanalyzed. The influence of coupling coefficient and quality factor on system efficiency was studied. The simulation results showed that the secondary side resonance compensation topology had a greater impact on the system efficiency,and the system efficiency was more sensitive to changes in the coupling coefficient and quality factors.Compared with the secondary side using the series compensation topology,the system had a wider range of high transfer efficiency when the secondary side used the parallel compensation topology. The experimental results verified the correctness of the simulation results.
2021, 36(2)
:92-101.
doi: 10.12187/2021.02.012
Abstract:
Aiming at the problems of complicated calculation process, large neutral pointe potential fluctuation and large output current harmonic of the traditional three-level ANPC grid-connected inverter limited control set model predictive control, a current control method of three-level ANPC grid-connected inverter based on optimized cost function was proposed. This method simplified the steps of establishing the intermediate variable of the DC side mid-point voltage offset ΔUdc and the three-phase switching state Sx in the traditional model predictive control method.Under the static αβ coordinate system, the relationship between load current i, ΔUdc and Sx was used to directly establish a mathematical model.Through the real-time calculation of 27 switch states, the optimal output switch state was selected.Simulation and experiment result showed that the method effectively reduced the total harmonic distortion rate and achieved the effect of suppressing midpoint voltage fluctuations.
Aiming at the problems of complicated calculation process, large neutral pointe potential fluctuation and large output current harmonic of the traditional three-level ANPC grid-connected inverter limited control set model predictive control, a current control method of three-level ANPC grid-connected inverter based on optimized cost function was proposed. This method simplified the steps of establishing the intermediate variable of the DC side mid-point voltage offset ΔUdc and the three-phase switching state Sx in the traditional model predictive control method.Under the static αβ coordinate system, the relationship between load current i, ΔUdc and Sx was used to directly establish a mathematical model.Through the real-time calculation of 27 switch states, the optimal output switch state was selected.Simulation and experiment result showed that the method effectively reduced the total harmonic distortion rate and achieved the effect of suppressing midpoint voltage fluctuations.
2021, 36(2)
:102-108.
doi: 10.12187/2021.02.013
Abstract:
A stochastic uncertain dynamic model was put forward for power systems with asynchronous wind turbines. Based on the stochastic differential equation,matrix theory and other related theories,a Lyapunov function was constructed according to the probability stability theorem,and the stochastic small disturbance interval stability of the asynchronous wind turbine with parameter perturbation was analyzed by differential operator. Simulation results verified the validity of the proposed probabilistic stability theorem for power systems with parameter perturbation.
A stochastic uncertain dynamic model was put forward for power systems with asynchronous wind turbines. Based on the stochastic differential equation,matrix theory and other related theories,a Lyapunov function was constructed according to the probability stability theorem,and the stochastic small disturbance interval stability of the asynchronous wind turbine with parameter perturbation was analyzed by differential operator. Simulation results verified the validity of the proposed probabilistic stability theorem for power systems with parameter perturbation.
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
