Based on analysis of geophysical data such as core observation, rock slices identification, physical property, scanning electron microscope, X-ray diffraction, logging data etc., 16 factors of sedimentation, diagenesi...Based on analysis of geophysical data such as core observation, rock slices identification, physical property, scanning electron microscope, X-ray diffraction, logging data etc., 16 factors of sedimentation, diagenesis, fluid pressure, and their relationships with reservoir physical property were analyzed, and the results indicate sedimentation is the internal factor controlling the reservoir property, diagenesis is the external and final decisive factor and abnormal fluid pressure is an important factor preserving the deep reservoir property. Quantitative characterization of diagenesis indicates that compaction and dissolution are more important than cementation and they respectively cause porosity change of-23.6% and 7.7% and -6.2%. Through optimizing 11 main controlling factors and constructing reservoir evaluation index (REI) according to the hierarchical cluster and principal component analysis, reservoir classification standard was established and reservoirs were divided into four classes. The studies show that Es~ SQ4 consists mainly of class I and II, while Es~ SQ6 is mainly of class III and II; the favorable zone is the north and south slope of Qibei sub-sag and the Liujianfang fault-nose. The successful application of the quantitative and comprehensive evaluation in the Qibei area verifies the advanced, practicable method of less artificial factor is suitable for the low porosity and permeability reservoir.展开更多
Based on the water quality monitoring data of 5 large reservoirs in Ji’an City,Jiangxi Province from 2015-2021,the temporal and spatial variation characteristics and trends of water quality of the reservoirs were ana...Based on the water quality monitoring data of 5 large reservoirs in Ji’an City,Jiangxi Province from 2015-2021,the temporal and spatial variation characteristics and trends of water quality of the reservoirs were analyzed by single-factor evaluation method and seasonal Kendall test to evaluate the trophic status of the reservoirs and explore the influencing factors of characteristic pollutants.The results showed that:①the water quality of the reservoirs was good and could meet the water needs of various functions;②the water quality of the reservoirs had generally changed from bad to good in recent years,indicating that the implementation of“river chief system”has achieved certain results;③Kendall test analysis showed that,except for individual projects which showed an upward trend in water quality,other projects showed no obvious change trend or downward trend,indicating that the water quality of the reservoirs is indeed improving;④the causes of water pollution in reservoir area were further analyzed by exploring the natural and human factors of the characteristic pollutant total phosphorus.It is recommended to strengthen supervision in the later stage to control point and non-point source pollution.展开更多
Micro-arc oxidation (MAO) process was carried out in a dual electrolyte system of NaAlO 2 and Na 3 PO 4 to develop compact, smooth and corrosion-resistant coatings on ZK60 Mg alloy by single factor experiments. The ...Micro-arc oxidation (MAO) process was carried out in a dual electrolyte system of NaAlO 2 and Na 3 PO 4 to develop compact, smooth and corrosion-resistant coatings on ZK60 Mg alloy by single factor experiments. The microstructural characteristics of coatings were investigated by X-ray diffractometry (XRD) and scanning electron microscopy (SEM) coupled with energy dispersive X-ray spectroscopy (EDS). Test of mass loss was conducted at a 3.5% NaCl solution to assess the resistance to corrosion. The effect of every element in the dual electrolyte system on voltage—time responses during MAO process and the coating characteristic were also analyzed and discussed systematically via single factor experiments. The results reveal that the main components of NaAlO 2 and Na 3 PO 4 as well as additives of NaOH, NaB4O7 and C6H5Na3O7 demonstrate different effects on MAO process and coating characteristics. By means of single factor experiments, an optimized dual electrolyte system was developed, containing 17.5 g/L NaAlO 2, 5.0 g/LNa3 PO4, 5.0 g/L NaOH, 3.0 g/L NaB4O7 and 4.2g/LC6H5Na3O7 .展开更多
The water quality in the Danjiangkou Reservoir has attracted considerable attention from the Chinese public and government since the announcement of the Middle Route of the South to North Water Diversion Project (SN...The water quality in the Danjiangkou Reservoir has attracted considerable attention from the Chinese public and government since the announcement of the Middle Route of the South to North Water Diversion Project (SNWDP), which commenced transferring water in 2014. Integrated research on the evaluation, prediction, and protection of water quality in the Danjiangkou Reservoir was carried out in this study in order to improve environmental management. Based on 120 water samples, wherein 17 water quality indices were measured at 20 monitoring sites, a single factor evaluation method was used to evaluate the current status of water quality. The results show that the main indices influencing the water quality in the Danjiangkou Reservoir are total phosphorus (TP), permanganate index (CODM,), dissolved oxygen (DO), and five-day biochemical oxygen demand (BODs), and the concentrations of TP, BODs, ammonia nitrogen (NH3--N), CODM,, DO, and anionic surfactant (Surfa) do not reach the specified standard levels in the tributaries. Seasonal Mann--Kendall tests indicated that the CODMn concentration shows a highly significant increasing trend, and the TP concentration shows a significant increasing trend in the Danjiangkou Reservoir. The distribution of the main water quality indices in the Danjiangkou Reservoir was predicted using a two-dimensional water quality numerical model, and showed that the sphere of influence from the tributaries can spread across half of the Han Reservoir if the pollutants are not controlled. Cluster analysis (CA) results suggest that the Shending River is heavily polluted, that the Jianghe, Sihe, and Jianhe rivers are moderately polluted, and that they should be the focus of environmental remediation.展开更多
In this study,the 24 h tensile strength of new type acetone-urea-formaldehyde furan resin (nitrogen content 3%) was investigated by uniform design optimization.Four independent variables such as acetone:formaldehyde m...In this study,the 24 h tensile strength of new type acetone-urea-formaldehyde furan resin (nitrogen content 3%) was investigated by uniform design optimization.Four independent variables such as acetone:formaldehyde molar ratio (mol/mol),solution pH value,reaction temperature (℃) and reaction time (min) were considered in the experiments.U13(134) uniform design was employed and the equation of 24 h tensile strength model was obtained after 13 experimentations.The 24 h tensile strength was optimized by applying single factor experiments and stepwise non-linear regression analysis.Minitab (Minitab 15 trial version) and MATLAB (R2010a trial version) were used for data analysis.The t-value and p-value indicate that the major impact factors include the interaction effect of solution pH value and reaction temperature (X2X3),the linear terms of acetone:formaldehyde molar ratio (X1),reaction time (X4) followed by the square effects of acetone/formaldehyde molar ratio (X1X1).The optimized results were achieved with the acetone:formaldehyde molar ratio (mol/mol) at 3:1,solution pH value at 6.0,reaction temperature at 70℃,and reaction time at 140 min,respectively.This method can not only significantly reduce the number and cost of the tests,but also provide a good experimental design strategy for the development of furan resin.The investigation shows that the predicted results of 24 h tensile strength are consistent well with the experimental ones.展开更多
The high concentrations of Fe^(2+) and Mn^(2+) in acid mine drainage make it difficult and expensive to treat.It is urgent that we find a cheap and efficient adsorption material to treat Fe^(2+) and Mn^(2+).As a solid...The high concentrations of Fe^(2+) and Mn^(2+) in acid mine drainage make it difficult and expensive to treat.It is urgent that we find a cheap and efficient adsorption material to treat Fe^(2+) and Mn^(2+).As a solid waste in mining areas,coal gangue occupies a large area and pollutes the surrounding environment during the stacking process.Developing a method of resource utilization is thus a research hotspot.In this study,we modified spontaneous combustion gangue using NaOH,NaCl,and HCl by chemically modifying the minerals.We determined the optimal conditions for treating Fe^(2+) and Mn^(2+) in acid mine drainage with spontaneous combustion gangue and modified coal gangue using the single factor test method.Based on results of the static test,two dynamic test columns,column No.1(spontaneous combustion gangue)and column No.2(NaOH modified spontaneous combustion gangue),were constructed,and the repair effects of acid mine drainage were compared and analyzed using dynamic experiments.The results show that overall,NaOH modified spontaneous combustion gangue is the most efficient at removing the Fe^(2+) and Mn^(2+) in acid mine drainage.The optimal conditions for NaOH modification are an NaOH concentration of 3 mol/L,a liquid to solid ratio of 2 L/kg,and a modification time of 8 h.The overall efficiency of column No.2 at removing Fe^(2+) and Mn^(2+) from acid mine drainage is better than that of column No.1.Among them,the average removal efficiency of Fe^(2+)and Mn^(2+) from acid mine drainage in column No.2 were 97.73%and 44.82%,respectively.The above results show that NaOH modified spontaneous combustion gangue is a good adsorbent,which has application potential in wastewater remediation,as it can achieve the purpose of“treating dust with waste”.展开更多
[ Objective] The content of total antimony (Sb) in fresh fruit was investigated and its pollution was evaluated, to provide the basic data for diet exposure evaluation. [ Method] The content of total Sb in 194 sampl...[ Objective] The content of total antimony (Sb) in fresh fruit was investigated and its pollution was evaluated, to provide the basic data for diet exposure evaluation. [ Method] The content of total Sb in 194 samples was detected by hydride generation-atomic fluorescence spectrometry (HG-AFS), and the Sb pollution in several fruits was evaluated by the method of single factor pollution index. [ Result ] The mean of total Sb was 0. 005 6 mg/kg, and the median was 0.003 8 mg/kg. The minimum value was not detected while the maximum value was O. 21 mg/kg, and the confidence interval was ND-O. 019 mg/kg (PS-P95). The medi- ans of total Sb content in different fruits successively were dragon fruit (0.011 0 mg/kg) 〉 kiwi fruit (0.008 0 mg/kg) 〉 peach (0.006 0 mg/kg). According to the method of single factor pollution index, the index from all samples was less than 0.2, suggesting that the samples involved were under the normal background value. [ Conclusion ] The Sb was detected in all samples but under the background value, and it was concluded that there was no Sb pollution in fresh fruit in Hunan Province.展开更多
A novel redox-responsive PEG-sheddable copolymer of disulfide-linked polyethylene glycol 5000-lysine-di-tocopherol succinate(P_(5k)SSLV)was designed and synthesized.Thin-film hydration method was used to prepare DOX-l...A novel redox-responsive PEG-sheddable copolymer of disulfide-linked polyethylene glycol 5000-lysine-di-tocopherol succinate(P_(5k)SSLV)was designed and synthesized.Thin-film hydration method was used to prepare DOX-loaded P_(5k)SSLV nanomicelle.To optimize the preparation technology,we investigate the effects of dosage,type of organic solvent,hydration temperature and time,and cryoprotectant on drug-loading content,encapsulation efficiency,particle size,and zeta potential.The mean particle size and zeta potential were determined by Zetasizer.The morphology of the P_(5k)SSLV-DOX nanomicelles was visualized by transmission electron microscopy.The drug-loading content and encapsulation efficiency of P_(5k)SSLV-DOX nanomicelle were investigated by UV.The drug-loading content,encapsulation efficiency,particle size,and zeta potential of the final optimized nanomicelles were 4.58%,97.20%,30.21 nm and -0.84 mV,respectively.In addition,the stability of nanomicelles was investigated,which included dilution stability and storage stability.The results showed that P_(5k)SSLV-DOX nanomicelle had good dilution stability and storage stability at 4℃.The preparation method of P_(5k)SSLV-DOX nanomicelle with thinfilm hydration method was practical and simple,which was valuable to be further studied.展开更多
This paper studies discrete investment portfolio model that the objective function is utility function. According to a hybrid branch-and-bound method based on Lagrangian relaxation and continuous relaxation, the paper...This paper studies discrete investment portfolio model that the objective function is utility function. According to a hybrid branch-and-bound method based on Lagrangian relaxation and continuous relaxation, the paper analyzes the question using the real statistical data. The results indicate that discrete investment portfolio model really has its guidance in the actual investment.展开更多
[Objectives] To extract the flavonoids from leaves of Coix lacryma-jobi L. [Methods] Ethanol extraction method was adopted,spectrophotometry was used,and single factor experiment and orthogonal experiment were carried...[Objectives] To extract the flavonoids from leaves of Coix lacryma-jobi L. [Methods] Ethanol extraction method was adopted,spectrophotometry was used,and single factor experiment and orthogonal experiment were carried out to study the effects of ethanol percentage,extraction temperature,solid-to-liquid ratio and extraction time on the extraction of total flavonoids from leaves of C. lacryma-jobi L.[Results] The order of 4 factors influencing the extraction of flavonoids from leaves of C. lacryma-jobi L. was: solid-to-liquid ratio > extraction time > ethanol percentage > extraction temperature. When the extraction temperature was 70℃,the extraction time was 1. 5 h and the solid-liquid ratio was 1: 10,the ethanol percentage was 60%,the extraction effect was the best,extraction of flavonoids was 0. 107 5 mg/m L.[Conclusions] This study is expected to provide a theoretical basis for further development and utilization of C. lacryma-jobi L.展开更多
[ Objective ] This study aimed to establish and optimize the ISSR-PCR reaction system and amplification process for Elymus sibiricus L. , to provide sci- entific basis for exploring the genetic diversity of E. sibiric...[ Objective ] This study aimed to establish and optimize the ISSR-PCR reaction system and amplification process for Elymus sibiricus L. , to provide sci- entific basis for exploring the genetic diversity of E. sibiricus germplasm resources. [ Method] Orthogonal design and single factor test were applied to establish the ISSR-PCR reaction system of E. sibiricus, optimize the influencing factors including Taq DNA polymerase, DNA template concentration, Mg2 + , dNTP, primer concentration, and screen the annealing temperature, number of cycles and extension time. [ Result ] The optimal reaction system for ISSR analysis contains 0.2 mmol/L dNTPs, 0.2 μmol/L ISSR primers, 1.5 U of Taq DNA polymerase, 2.5 μl of 10 × PCR Buffer, 1.5 mmol/L MgC12 and 40 ng of template DNA in 25 μl total volume; the amplification was conducted with 35 cycles and extension time of 90 s. [ Conclusion] ISSR-PCR reaction system for E. sibiricus was established and optimized, and then verified using two E. sibiricus germplasrns, demonstrating that the ISSR-PCR reaction system is stable and can be used for the genetic analysis of E. sibiricus.展开更多
[Objectives]This study was conducted to screen best process parameters for making Foshou yam and honey can.[Methods]The Foshou yam produced from Wuxue was used as a raw material to prepare Foshou yam and honey nutriti...[Objectives]This study was conducted to screen best process parameters for making Foshou yam and honey can.[Methods]The Foshou yam produced from Wuxue was used as a raw material to prepare Foshou yam and honey nutritional can by combining Foshou yam with honey through screening,pre-cooking,filling,exhausting,cooling and other technical processes.The optimum technology parameter of Foshou yam and honey nutritional can was studied through single factor tests and response surface optimization.[Results]The optimum technical parameters of Foshou yam and honey nutritional can were citric acid concentration 0.1%,amount of edible salt 0.1%,cooking time 14 min and honey concentration 26%.Under these conditions,the final sensory score was 90.20.The prepared can was not only rich in nutrition,but also had good flavor and taste.[Conclusions]This study provides reference for the development and utilization of Foshou yam and the research and development of functional food.展开更多
[Objectives] The chlorogenic acid in Sambucus chinensis Lindl is a kind of biologically active substance with multiple pharmacological effects, but the content is relatively small. It is of great significance to find ...[Objectives] The chlorogenic acid in Sambucus chinensis Lindl is a kind of biologically active substance with multiple pharmacological effects, but the content is relatively small. It is of great significance to find the best extraction process. Therefore, we designed single factor experiments and orthogonal experiments to screen the best conditions for extracting chlorogenic acid from S. chinensis. [Methods] With ethanol concentration, ultrasonic power, and extraction time as three single factors, single factor experiments were performed on S. chinensis, and its chlorogenic acid content was calculated from a standard curve. The contents of chlorogenic acid obtained under various conditions were compared, and then, orthogonal experiments were designed according to the orthogonal table to analyze the optimal extraction conditions of chlorogenic acid. [Results] The optimal extraction conditions of chlorogenic acid for S. chinensis were: the ethanol concentration 60%, the ultrasonic power 36 W, and the extraction time 40 min.[Conclusions] The factor that had the greatest effect on the extraction rate of chlorogenic acid in S. chinensis was ethanol concentration, followed by extraction time, and the least influencing factor was ultrasonic power. With 60% ethanol solution serving as the extractant, the ultrasonic power of 36 W, and the extraction time of 40 min, a better extraction rate was obtained. These conditions can be used as the best extraction conditions for chlorogenic acid.展开更多
[Objectives]To detect content of Pb,Cd,Hg,As,Cu,Zn,and Cr in Lysimachia christinae,and to analyze the pollution level.[Methods]Seven kinds of elements in L.christinae were determined by Inductively coupled plasma mass...[Objectives]To detect content of Pb,Cd,Hg,As,Cu,Zn,and Cr in Lysimachia christinae,and to analyze the pollution level.[Methods]Seven kinds of elements in L.christinae were determined by Inductively coupled plasma mass spectrometry and analyzed by single index and comprehensive index.[Results]The seven heavy metal elements showed good linearity in their respective concentration ranges.The recoveries of the samples were 84.5%-109.5%,and the RSD values were 2.30%-5.10%.Comparing the measured results of heavy metal elements with the limit values stipulated in the 2020 edition of the Chinese Pharmacopoeia and other standards,the Cr element in 19 batches of samples exceeded the standard,and the Zn element in 7 batches of samples exceeded the standard.The exceeding rates were 100.0%and 36.8%,respectively;the content of other heavy metal elements did not exceed the standard.The order of individual index from large to small was Cr,Zn,Cd,Hg,Cu,As,and Pb,and the average comprehensive pollution level was mild pollution and above.[Conclusions]L.christinae was mainly polluted by Cr,followed by Zn;this study can provide basic data for drafting of the limit standard for heavy metal elements in L.christinae.展开更多
[Objective] The paper was to evaluate the water quality environment in Dachangshan artificial habitat development demonstration area.[Method] From 2013 to 2015, an environmental survey was conducted for eight voyages ...[Objective] The paper was to evaluate the water quality environment in Dachangshan artificial habitat development demonstration area.[Method] From 2013 to 2015, an environmental survey was conducted for eight voyages in Dachangshan artificial habitat development demonstration area of Changhai County, Dalian City, and 20 hydrochemical indexes including salinity, pH, and COD were monitored. The water quality of thesea area was analyzed by principal component analysis and single factor index method. [Result] Except for that the control area of the August 2014voyage belonged to IIclass sea water standard, the water quality in other stations of all voyages conformed toIclass sea water standard. Totally 20water quality indicators were synthesized into six principal components using principal component analysis, which explained 79.165% of the results;the principal component score was ranged from -1.536 to 3.706; the score in August 2014 was the highest, and the evaluation results were basicallyconsistent with the results of single factor index analysis. [Conclusion] The overall water quality is good in Dachangshan artificial habitat development demonstration area.展开更多
In this paper,the liquid seed medium of Grifola frondosa was optimized by single factor and orthogonal experiments using the shake flask culture method.The single factor experiments results showed that soybean powder ...In this paper,the liquid seed medium of Grifola frondosa was optimized by single factor and orthogonal experiments using the shake flask culture method.The single factor experiments results showed that soybean powder and maltose were the optimal nitrogen and carbon sources,and MgSO4 was the optimal inorganic salt.The orthogonal experiment results showed that the optimal combination of liquid seed culture medium for Grifola frondosa was:20%potato,0.75%soybean powder,5%maltose,0.1%KH2PO4,0.05%MgSO4,0.001%VB1.Using the optimized medium,shaking culture for 10 d under the inoculum amount of 5%,the temperature of 28℃,and the rotation speed of 150 r/min,the dry weight of mycelium exceeded 1.3228 g/100mL.展开更多
[Objectives] This study was conducted to determine the optimum process conditions for the preparation of alkali-soluble pachymaran rice wine. [Methods] A new type of alkali-soluble pachymaran rice wine was prepared by...[Objectives] This study was conducted to determine the optimum process conditions for the preparation of alkali-soluble pachymaran rice wine. [Methods] A new type of alkali-soluble pachymaran rice wine was prepared by mixing and fermenting alkali-soluble pachymaran and glutinous rice as raw materials. The sensory score was used as the evaluation index to investigate the effects of three factors including the amount of alkali-soluble pachymaran, inoculation amount and fermentation temperature on the quality of the alkali-soluble pachymaran rice wine. The fermentation process of the rice wine was then optimized by an orthogonal experiment. [Results] With the proportion of the alkali-soluble pachymaran added of 0.4%, the inoculation amount of 0.6% and the fermentation temperature at 30 ℃, the sensory score of the prepared rice wine was the highest, which was 93.5 points. The alkali-soluble pachymaran rice wine prepared under above conditions was rich in flavor and tasted sweet and sour. [Conclusions] The production of the new rice wine and the understanding of the development history of rice wine will provide reference for the future development of rice wine industry, and provide research directions for the development of new health drinks.展开更多
The effects of process variables in Simultaneous Saccharification and Fermentation (SSF) of wheat bran flour were studied in bulk fermentation using a coculture of Aspergillus niger - Kluveromyces marxianus. The effec...The effects of process variables in Simultaneous Saccharification and Fermentation (SSF) of wheat bran flour were studied in bulk fermentation using a coculture of Aspergillus niger - Kluveromyces marxianus. The effect of substrate density, pH, temperature, and enzyme concentration on wheat bran was predicted by designing experiments in which a single parameter is varied keeping other variables at a constant level. The above parameters were optimized for a batch culture in a fermentor. Optimal values for substrate concentration, pH, temperature, and enzyme concentration during processing were 200 g/l, 5.5, 65°C, and 7.5 IU, respectively. In pre-treatment experiments, the concentration of enzymes and the pre-treatment temperature are highly correlated. The influence of pH, temperature, and substrate density on ethanol production was investigated. Temperature pH was determined as optimal, 32°C and 5.5, respectively. After 48 hours of fermentation at optimum pH, a solution of wheat bran containing a maximum of 6% starch produces a maximum of 22.9 g/l ethanol.展开更多
AIM:To investigate the association between three tag single nucleotide polymorphisms (tagSNPs) in inter-feron regulatory factors (IRF3) and the genetic suscep-tibility to chronic hepatitis B virus (HBV) infection.METH...AIM:To investigate the association between three tag single nucleotide polymorphisms (tagSNPs) in inter-feron regulatory factors (IRF3) and the genetic suscep-tibility to chronic hepatitis B virus (HBV) infection.METHODS:We performed a case-control study of 985 Chinese cases of chronic HBV infection and 294 self-limiting HBV-infected individuals as controls.Three tagSNPs in IRF3 (rs10415576,rs2304204,rs2304206) were genotyped with the Multiplex SNaPshot technique.The genotype and allele frequencies were calculatedand analyzed.RESULTS:The three SNPs showed no significant geno-type/allele associations with chronic HBV infection.Overall allele P values were:rs10415576,P=0.0908,odds ratio (OR) [95% confidence interval (CI)]=1.1798 (0.9740-1.4291);rs2304204,P=0.5959,OR (95% CI)=1.0597 (0.8552-1.3133);rs2304206,P=0.8372,OR (95% CI)=1.0250 (0.8097-1.2976).Overall genotype P values were:rs10415576,P=0.2106;rs2304204,P=0.8458;rs2304206,P=0.8315.There were no statisti-cally significant differences between patients with chron-ic HBV infection and controls.Haplotypes generated by these three SNPs were also not significantly different between the two groups.CONCLUSION:The three tagSNPs of IRF3 are not asso-ciated with HBV infection in the Han Chinese population.展开更多
文摘Based on analysis of geophysical data such as core observation, rock slices identification, physical property, scanning electron microscope, X-ray diffraction, logging data etc., 16 factors of sedimentation, diagenesis, fluid pressure, and their relationships with reservoir physical property were analyzed, and the results indicate sedimentation is the internal factor controlling the reservoir property, diagenesis is the external and final decisive factor and abnormal fluid pressure is an important factor preserving the deep reservoir property. Quantitative characterization of diagenesis indicates that compaction and dissolution are more important than cementation and they respectively cause porosity change of-23.6% and 7.7% and -6.2%. Through optimizing 11 main controlling factors and constructing reservoir evaluation index (REI) according to the hierarchical cluster and principal component analysis, reservoir classification standard was established and reservoirs were divided into four classes. The studies show that Es~ SQ4 consists mainly of class I and II, while Es~ SQ6 is mainly of class III and II; the favorable zone is the north and south slope of Qibei sub-sag and the Liujianfang fault-nose. The successful application of the quantitative and comprehensive evaluation in the Qibei area verifies the advanced, practicable method of less artificial factor is suitable for the low porosity and permeability reservoir.
基金Hydraulic Science and Technology Project of Water Resources Department of Jiangxi Province(202324YBKT14)Youth Science and Technology Innovation Fund of Jiangxi Hydrology Monitoring Center(SWJJKT202208).
文摘Based on the water quality monitoring data of 5 large reservoirs in Ji’an City,Jiangxi Province from 2015-2021,the temporal and spatial variation characteristics and trends of water quality of the reservoirs were analyzed by single-factor evaluation method and seasonal Kendall test to evaluate the trophic status of the reservoirs and explore the influencing factors of characteristic pollutants.The results showed that:①the water quality of the reservoirs was good and could meet the water needs of various functions;②the water quality of the reservoirs had generally changed from bad to good in recent years,indicating that the implementation of“river chief system”has achieved certain results;③Kendall test analysis showed that,except for individual projects which showed an upward trend in water quality,other projects showed no obvious change trend or downward trend,indicating that the water quality of the reservoirs is indeed improving;④the causes of water pollution in reservoir area were further analyzed by exploring the natural and human factors of the characteristic pollutant total phosphorus.It is recommended to strengthen supervision in the later stage to control point and non-point source pollution.
基金Project(JSAWT-09-02)supported by the Key Laboratory of Advanced Welding Technology of Jiangsu Province,ChinaProject supported by the Priority Academic Program Development of Jiangsu Higher Education Institutions,China
文摘Micro-arc oxidation (MAO) process was carried out in a dual electrolyte system of NaAlO 2 and Na 3 PO 4 to develop compact, smooth and corrosion-resistant coatings on ZK60 Mg alloy by single factor experiments. The microstructural characteristics of coatings were investigated by X-ray diffractometry (XRD) and scanning electron microscopy (SEM) coupled with energy dispersive X-ray spectroscopy (EDS). Test of mass loss was conducted at a 3.5% NaCl solution to assess the resistance to corrosion. The effect of every element in the dual electrolyte system on voltage—time responses during MAO process and the coating characteristic were also analyzed and discussed systematically via single factor experiments. The results reveal that the main components of NaAlO 2 and Na 3 PO 4 as well as additives of NaOH, NaB4O7 and C6H5Na3O7 demonstrate different effects on MAO process and coating characteristics. By means of single factor experiments, an optimized dual electrolyte system was developed, containing 17.5 g/L NaAlO 2, 5.0 g/LNa3 PO4, 5.0 g/L NaOH, 3.0 g/L NaB4O7 and 4.2g/LC6H5Na3O7 .
基金supported by the National Natural Science Foundation of China(Grants No.41101250 and 51309031)the Chinese 12th Five-Year Science and Technology Support Program(Grant No.2012BAC06B00)
文摘The water quality in the Danjiangkou Reservoir has attracted considerable attention from the Chinese public and government since the announcement of the Middle Route of the South to North Water Diversion Project (SNWDP), which commenced transferring water in 2014. Integrated research on the evaluation, prediction, and protection of water quality in the Danjiangkou Reservoir was carried out in this study in order to improve environmental management. Based on 120 water samples, wherein 17 water quality indices were measured at 20 monitoring sites, a single factor evaluation method was used to evaluate the current status of water quality. The results show that the main indices influencing the water quality in the Danjiangkou Reservoir are total phosphorus (TP), permanganate index (CODM,), dissolved oxygen (DO), and five-day biochemical oxygen demand (BODs), and the concentrations of TP, BODs, ammonia nitrogen (NH3--N), CODM,, DO, and anionic surfactant (Surfa) do not reach the specified standard levels in the tributaries. Seasonal Mann--Kendall tests indicated that the CODMn concentration shows a highly significant increasing trend, and the TP concentration shows a significant increasing trend in the Danjiangkou Reservoir. The distribution of the main water quality indices in the Danjiangkou Reservoir was predicted using a two-dimensional water quality numerical model, and showed that the sphere of influence from the tributaries can spread across half of the Han Reservoir if the pollutants are not controlled. Cluster analysis (CA) results suggest that the Shending River is heavily polluted, that the Jianghe, Sihe, and Jianhe rivers are moderately polluted, and that they should be the focus of environmental remediation.
文摘In this study,the 24 h tensile strength of new type acetone-urea-formaldehyde furan resin (nitrogen content 3%) was investigated by uniform design optimization.Four independent variables such as acetone:formaldehyde molar ratio (mol/mol),solution pH value,reaction temperature (℃) and reaction time (min) were considered in the experiments.U13(134) uniform design was employed and the equation of 24 h tensile strength model was obtained after 13 experimentations.The 24 h tensile strength was optimized by applying single factor experiments and stepwise non-linear regression analysis.Minitab (Minitab 15 trial version) and MATLAB (R2010a trial version) were used for data analysis.The t-value and p-value indicate that the major impact factors include the interaction effect of solution pH value and reaction temperature (X2X3),the linear terms of acetone:formaldehyde molar ratio (X1),reaction time (X4) followed by the square effects of acetone/formaldehyde molar ratio (X1X1).The optimized results were achieved with the acetone:formaldehyde molar ratio (mol/mol) at 3:1,solution pH value at 6.0,reaction temperature at 70℃,and reaction time at 140 min,respectively.This method can not only significantly reduce the number and cost of the tests,but also provide a good experimental design strategy for the development of furan resin.The investigation shows that the predicted results of 24 h tensile strength are consistent well with the experimental ones.
基金This work was supported by the National Natural Science Foundation of China(Nos.51304114,41672247)the Scientific Research Fund of the Liaoning Provincial Education Department(No.LJ2017FAL016).
文摘The high concentrations of Fe^(2+) and Mn^(2+) in acid mine drainage make it difficult and expensive to treat.It is urgent that we find a cheap and efficient adsorption material to treat Fe^(2+) and Mn^(2+).As a solid waste in mining areas,coal gangue occupies a large area and pollutes the surrounding environment during the stacking process.Developing a method of resource utilization is thus a research hotspot.In this study,we modified spontaneous combustion gangue using NaOH,NaCl,and HCl by chemically modifying the minerals.We determined the optimal conditions for treating Fe^(2+) and Mn^(2+) in acid mine drainage with spontaneous combustion gangue and modified coal gangue using the single factor test method.Based on results of the static test,two dynamic test columns,column No.1(spontaneous combustion gangue)and column No.2(NaOH modified spontaneous combustion gangue),were constructed,and the repair effects of acid mine drainage were compared and analyzed using dynamic experiments.The results show that overall,NaOH modified spontaneous combustion gangue is the most efficient at removing the Fe^(2+) and Mn^(2+) in acid mine drainage.The optimal conditions for NaOH modification are an NaOH concentration of 3 mol/L,a liquid to solid ratio of 2 L/kg,and a modification time of 8 h.The overall efficiency of column No.2 at removing Fe^(2+) and Mn^(2+) from acid mine drainage is better than that of column No.1.Among them,the average removal efficiency of Fe^(2+)and Mn^(2+) from acid mine drainage in column No.2 were 97.73%and 44.82%,respectively.The above results show that NaOH modified spontaneous combustion gangue is a good adsorbent,which has application potential in wastewater remediation,as it can achieve the purpose of“treating dust with waste”.
基金Supported by Scientific Research Project of Medicine and Health Care in Hunan Province(B2014-162)Scientific Research Project of Xiangtan Science and Technology Bureau(SF20141003)
文摘[ Objective] The content of total antimony (Sb) in fresh fruit was investigated and its pollution was evaluated, to provide the basic data for diet exposure evaluation. [ Method] The content of total Sb in 194 samples was detected by hydride generation-atomic fluorescence spectrometry (HG-AFS), and the Sb pollution in several fruits was evaluated by the method of single factor pollution index. [ Result ] The mean of total Sb was 0. 005 6 mg/kg, and the median was 0.003 8 mg/kg. The minimum value was not detected while the maximum value was O. 21 mg/kg, and the confidence interval was ND-O. 019 mg/kg (PS-P95). The medi- ans of total Sb content in different fruits successively were dragon fruit (0.011 0 mg/kg) 〉 kiwi fruit (0.008 0 mg/kg) 〉 peach (0.006 0 mg/kg). According to the method of single factor pollution index, the index from all samples was less than 0.2, suggesting that the samples involved were under the normal background value. [ Conclusion ] The Sb was detected in all samples but under the background value, and it was concluded that there was no Sb pollution in fresh fruit in Hunan Province.
文摘A novel redox-responsive PEG-sheddable copolymer of disulfide-linked polyethylene glycol 5000-lysine-di-tocopherol succinate(P_(5k)SSLV)was designed and synthesized.Thin-film hydration method was used to prepare DOX-loaded P_(5k)SSLV nanomicelle.To optimize the preparation technology,we investigate the effects of dosage,type of organic solvent,hydration temperature and time,and cryoprotectant on drug-loading content,encapsulation efficiency,particle size,and zeta potential.The mean particle size and zeta potential were determined by Zetasizer.The morphology of the P_(5k)SSLV-DOX nanomicelles was visualized by transmission electron microscopy.The drug-loading content and encapsulation efficiency of P_(5k)SSLV-DOX nanomicelle were investigated by UV.The drug-loading content,encapsulation efficiency,particle size,and zeta potential of the final optimized nanomicelles were 4.58%,97.20%,30.21 nm and -0.84 mV,respectively.In addition,the stability of nanomicelles was investigated,which included dilution stability and storage stability.The results showed that P_(5k)SSLV-DOX nanomicelle had good dilution stability and storage stability at 4℃.The preparation method of P_(5k)SSLV-DOX nanomicelle with thinfilm hydration method was practical and simple,which was valuable to be further studied.
基金Supported by the Key Project of Science and Technology Department of Henan Province(122102210060)
文摘This paper studies discrete investment portfolio model that the objective function is utility function. According to a hybrid branch-and-bound method based on Lagrangian relaxation and continuous relaxation, the paper analyzes the question using the real statistical data. The results indicate that discrete investment portfolio model really has its guidance in the actual investment.
基金Supported by Project of National Natural Science Foundation(81360684)Natural Science Foundation Project of Guangxi(2011GXNSFA018046)+3 种基金the 12th Five-Year TCM Key Discipline Chinese Medicine Chemistry Construction Program of State Administration of Traditional Chinese Medicine(Guo Zhong Yi Yao Ren Jiao Fa[2012]32)Key Discipline Chinese Medicine Chemistry Construction Program of Guangxi(Gui Jiao Ke Yan[2013]16)Program of Key Laboratory of Guangxi Universities on National Medicine in Youjiang River Basin(Gui Jiao Ke Yan[2014]14)Student’s Platform for Innovation and Entrepreneurship Training Program of Guangxi in 2015(201510599026)
文摘[Objectives] To extract the flavonoids from leaves of Coix lacryma-jobi L. [Methods] Ethanol extraction method was adopted,spectrophotometry was used,and single factor experiment and orthogonal experiment were carried out to study the effects of ethanol percentage,extraction temperature,solid-to-liquid ratio and extraction time on the extraction of total flavonoids from leaves of C. lacryma-jobi L.[Results] The order of 4 factors influencing the extraction of flavonoids from leaves of C. lacryma-jobi L. was: solid-to-liquid ratio > extraction time > ethanol percentage > extraction temperature. When the extraction temperature was 70℃,the extraction time was 1. 5 h and the solid-liquid ratio was 1: 10,the ethanol percentage was 60%,the extraction effect was the best,extraction of flavonoids was 0. 107 5 mg/m L.[Conclusions] This study is expected to provide a theoretical basis for further development and utilization of C. lacryma-jobi L.
基金Supported by Project of Collection,Cataloguing and Utilization of Perennial Forage Grass Germplasm Resources(NB2012-2130135-33)Conservation Project for Forage Grass Germplasm Resources
文摘[ Objective ] This study aimed to establish and optimize the ISSR-PCR reaction system and amplification process for Elymus sibiricus L. , to provide sci- entific basis for exploring the genetic diversity of E. sibiricus germplasm resources. [ Method] Orthogonal design and single factor test were applied to establish the ISSR-PCR reaction system of E. sibiricus, optimize the influencing factors including Taq DNA polymerase, DNA template concentration, Mg2 + , dNTP, primer concentration, and screen the annealing temperature, number of cycles and extension time. [ Result ] The optimal reaction system for ISSR analysis contains 0.2 mmol/L dNTPs, 0.2 μmol/L ISSR primers, 1.5 U of Taq DNA polymerase, 2.5 μl of 10 × PCR Buffer, 1.5 mmol/L MgC12 and 40 ng of template DNA in 25 μl total volume; the amplification was conducted with 35 cycles and extension time of 90 s. [ Conclusion] ISSR-PCR reaction system for E. sibiricus was established and optimized, and then verified using two E. sibiricus germplasrns, demonstrating that the ISSR-PCR reaction system is stable and can be used for the genetic analysis of E. sibiricus.
基金2018 Undergraduate Innovation and Entrepreneurship Training Program of Huanggang Normal University(201810514045)High-level Cultivation Project of Huanggang Normal University(201816703)。
文摘[Objectives]This study was conducted to screen best process parameters for making Foshou yam and honey can.[Methods]The Foshou yam produced from Wuxue was used as a raw material to prepare Foshou yam and honey nutritional can by combining Foshou yam with honey through screening,pre-cooking,filling,exhausting,cooling and other technical processes.The optimum technology parameter of Foshou yam and honey nutritional can was studied through single factor tests and response surface optimization.[Results]The optimum technical parameters of Foshou yam and honey nutritional can were citric acid concentration 0.1%,amount of edible salt 0.1%,cooking time 14 min and honey concentration 26%.Under these conditions,the final sensory score was 90.20.The prepared can was not only rich in nutrition,but also had good flavor and taste.[Conclusions]This study provides reference for the development and utilization of Foshou yam and the research and development of functional food.
文摘[Objectives] The chlorogenic acid in Sambucus chinensis Lindl is a kind of biologically active substance with multiple pharmacological effects, but the content is relatively small. It is of great significance to find the best extraction process. Therefore, we designed single factor experiments and orthogonal experiments to screen the best conditions for extracting chlorogenic acid from S. chinensis. [Methods] With ethanol concentration, ultrasonic power, and extraction time as three single factors, single factor experiments were performed on S. chinensis, and its chlorogenic acid content was calculated from a standard curve. The contents of chlorogenic acid obtained under various conditions were compared, and then, orthogonal experiments were designed according to the orthogonal table to analyze the optimal extraction conditions of chlorogenic acid. [Results] The optimal extraction conditions of chlorogenic acid for S. chinensis were: the ethanol concentration 60%, the ultrasonic power 36 W, and the extraction time 40 min.[Conclusions] The factor that had the greatest effect on the extraction rate of chlorogenic acid in S. chinensis was ethanol concentration, followed by extraction time, and the least influencing factor was ultrasonic power. With 60% ethanol solution serving as the extractant, the ultrasonic power of 36 W, and the extraction time of 40 min, a better extraction rate was obtained. These conditions can be used as the best extraction conditions for chlorogenic acid.
基金Supported by Risk Monitoring Task Project of Chongqing Drug Administration in 2020。
文摘[Objectives]To detect content of Pb,Cd,Hg,As,Cu,Zn,and Cr in Lysimachia christinae,and to analyze the pollution level.[Methods]Seven kinds of elements in L.christinae were determined by Inductively coupled plasma mass spectrometry and analyzed by single index and comprehensive index.[Results]The seven heavy metal elements showed good linearity in their respective concentration ranges.The recoveries of the samples were 84.5%-109.5%,and the RSD values were 2.30%-5.10%.Comparing the measured results of heavy metal elements with the limit values stipulated in the 2020 edition of the Chinese Pharmacopoeia and other standards,the Cr element in 19 batches of samples exceeded the standard,and the Zn element in 7 batches of samples exceeded the standard.The exceeding rates were 100.0%and 36.8%,respectively;the content of other heavy metal elements did not exceed the standard.The order of individual index from large to small was Cr,Zn,Cd,Hg,Cu,As,and Pb,and the average comprehensive pollution level was mild pollution and above.[Conclusions]L.christinae was mainly polluted by Cr,followed by Zn;this study can provide basic data for drafting of the limit standard for heavy metal elements in L.christinae.
基金Supported by Special Fund for Scientific Research (Marine) in the Public Interest(201205023)Nation Key Technology R&D Program(2012BAD18B02,2015BAD13B05)
文摘[Objective] The paper was to evaluate the water quality environment in Dachangshan artificial habitat development demonstration area.[Method] From 2013 to 2015, an environmental survey was conducted for eight voyages in Dachangshan artificial habitat development demonstration area of Changhai County, Dalian City, and 20 hydrochemical indexes including salinity, pH, and COD were monitored. The water quality of thesea area was analyzed by principal component analysis and single factor index method. [Result] Except for that the control area of the August 2014voyage belonged to IIclass sea water standard, the water quality in other stations of all voyages conformed toIclass sea water standard. Totally 20water quality indicators were synthesized into six principal components using principal component analysis, which explained 79.165% of the results;the principal component score was ranged from -1.536 to 3.706; the score in August 2014 was the highest, and the evaluation results were basicallyconsistent with the results of single factor index analysis. [Conclusion] The overall water quality is good in Dachangshan artificial habitat development demonstration area.
文摘In this paper,the liquid seed medium of Grifola frondosa was optimized by single factor and orthogonal experiments using the shake flask culture method.The single factor experiments results showed that soybean powder and maltose were the optimal nitrogen and carbon sources,and MgSO4 was the optimal inorganic salt.The orthogonal experiment results showed that the optimal combination of liquid seed culture medium for Grifola frondosa was:20%potato,0.75%soybean powder,5%maltose,0.1%KH2PO4,0.05%MgSO4,0.001%VB1.Using the optimized medium,shaking culture for 10 d under the inoculum amount of 5%,the temperature of 28℃,and the rotation speed of 150 r/min,the dry weight of mycelium exceeded 1.3228 g/100mL.
基金Supported by Youth Project of Hubei Education Department(03201718402)Huanggang Normal University High-level Cultivation Project(04201711903)
文摘[Objectives] This study was conducted to determine the optimum process conditions for the preparation of alkali-soluble pachymaran rice wine. [Methods] A new type of alkali-soluble pachymaran rice wine was prepared by mixing and fermenting alkali-soluble pachymaran and glutinous rice as raw materials. The sensory score was used as the evaluation index to investigate the effects of three factors including the amount of alkali-soluble pachymaran, inoculation amount and fermentation temperature on the quality of the alkali-soluble pachymaran rice wine. The fermentation process of the rice wine was then optimized by an orthogonal experiment. [Results] With the proportion of the alkali-soluble pachymaran added of 0.4%, the inoculation amount of 0.6% and the fermentation temperature at 30 ℃, the sensory score of the prepared rice wine was the highest, which was 93.5 points. The alkali-soluble pachymaran rice wine prepared under above conditions was rich in flavor and tasted sweet and sour. [Conclusions] The production of the new rice wine and the understanding of the development history of rice wine will provide reference for the future development of rice wine industry, and provide research directions for the development of new health drinks.
文摘The effects of process variables in Simultaneous Saccharification and Fermentation (SSF) of wheat bran flour were studied in bulk fermentation using a coculture of Aspergillus niger - Kluveromyces marxianus. The effect of substrate density, pH, temperature, and enzyme concentration on wheat bran was predicted by designing experiments in which a single parameter is varied keeping other variables at a constant level. The above parameters were optimized for a batch culture in a fermentor. Optimal values for substrate concentration, pH, temperature, and enzyme concentration during processing were 200 g/l, 5.5, 65°C, and 7.5 IU, respectively. In pre-treatment experiments, the concentration of enzymes and the pre-treatment temperature are highly correlated. The influence of pH, temperature, and substrate density on ethanol production was investigated. Temperature pH was determined as optimal, 32°C and 5.5, respectively. After 48 hours of fermentation at optimum pH, a solution of wheat bran containing a maximum of 6% starch produces a maximum of 22.9 g/l ethanol.
基金Supported by Grants from the National Natural Science Foundation of China,No.81072342the National Pre-973 Program Projects,No. 2009CB526411
文摘AIM:To investigate the association between three tag single nucleotide polymorphisms (tagSNPs) in inter-feron regulatory factors (IRF3) and the genetic suscep-tibility to chronic hepatitis B virus (HBV) infection.METHODS:We performed a case-control study of 985 Chinese cases of chronic HBV infection and 294 self-limiting HBV-infected individuals as controls.Three tagSNPs in IRF3 (rs10415576,rs2304204,rs2304206) were genotyped with the Multiplex SNaPshot technique.The genotype and allele frequencies were calculatedand analyzed.RESULTS:The three SNPs showed no significant geno-type/allele associations with chronic HBV infection.Overall allele P values were:rs10415576,P=0.0908,odds ratio (OR) [95% confidence interval (CI)]=1.1798 (0.9740-1.4291);rs2304204,P=0.5959,OR (95% CI)=1.0597 (0.8552-1.3133);rs2304206,P=0.8372,OR (95% CI)=1.0250 (0.8097-1.2976).Overall genotype P values were:rs10415576,P=0.2106;rs2304204,P=0.8458;rs2304206,P=0.8315.There were no statisti-cally significant differences between patients with chron-ic HBV infection and controls.Haplotypes generated by these three SNPs were also not significantly different between the two groups.CONCLUSION:The three tagSNPs of IRF3 are not asso-ciated with HBV infection in the Han Chinese population.