The effects of zinc （Zn） at different spray concentra- tions （0, 500, and 1 000 μmol · L-1 ） on the plant growth, the ac- tivities of antioxidant enzymes chemical forms of cadmium （Cd）, and the accumulatio...The effects of zinc （Zn） at different spray concentra- tions （0, 500, and 1 000 μmol · L-1 ） on the plant growth, the ac- tivities of antioxidant enzymes chemical forms of cadmium （Cd）, and the accumulation of Cd were studied and compared between two varieties, Shijichaotianjiao （SJCTJ） and Yanjiao425 （YJ425） of pepper （Capsicum annuum L.） in Cd-contaminated soil （Cd 10 mg @ kg-1 ）. The activities of catalase （CAT） and peroxidase （POD） were generally enhanced by Zn. However, superoxide dismutase （SOD） decreased. Addition of Zn decreased the ethanol-extract- able Cd, NaCl-extractable Cd, and acetic acid-extractable Cd in the fruit by 34.6%- 55.3%, 2.0%-17.7% and 0.4%-32.9%, and reduced the accumulation of Cd in fruit and plant total Cd by 12.8%- 68.6% and 9.0%-29.3% in both varieties, respectively.展开更多
Cadmium(Cd)pollution in agricultural soils has exerted a serious threat due to continuous application of pesticides,fertilizers,and wastewater irrigation.The present study aimed to test the efficiency of KOH-modified ...Cadmium(Cd)pollution in agricultural soils has exerted a serious threat due to continuous application of pesticides,fertilizers,and wastewater irrigation.The present study aimed to test the efficiency of KOH-modified and non-modified rice straw-derived biochar(KBC and BC,respectively)for reducing Cd solubility and bioavailability in Cd-contaminated soil.Cadmium-contaminated soil was incubated for 60 d with 15 and 30 g kg-1 BC and KBC.At the end of incubation,Cd mobility was estimated by the European Community Bureau of Reference sequential extraction and toxicity characteristic leaching procedure(TCLP),while bioavailability was determined using 1 molL-1 NH4NO3 extraction.The bioavailability risk index and bioaccessibility,assessed by a simple bioaccessibility extraction test,of Cd were used to examine the potential effects of Cd on living organisms.The results indicated that application of both KBC and BC significantly increased soil p H,cation exchange capacity,nutrients,and organic carbon.The soluble fraction of Cd was significantly decreased by 30.3%and 27.4%,respectively,with the addition of KBC and BC at 30 g kg-1 compared to the control(without biochar addition).Similarly,the bioaccessible Cd was significantly decreased by 32.4%and 25.2%,respectively,with the addition of KBC and BC at 30 g kg-1 compared to the control.In addition,both KBC and BC significantly reduced Cd leaching in the TCLP and NH4NO3-extractable Cd in the amended soil compared to the control.The reduction in Cd solubility and bioaccessibility by KBC and BC may be due to significant increases in soil pH and surface complexation.Overall,KBC at an application rate of 30 g kg-1 demonstrated positive results as soil amendment for Cd immobilization,and reduced bioaccessible Cd in contaminated soil.展开更多
为遴选可有效表征农田土壤Cd生物有效性的指标,文章采集浙江某地20组稻米及其协同土壤,分析稻米Cd质量比、土壤的基本理化性质、Cd总质量比、不同浸提态Cd质量比及欧共体标准物质局(European Community Bureau of Reference,BCR)形态。...为遴选可有效表征农田土壤Cd生物有效性的指标,文章采集浙江某地20组稻米及其协同土壤,分析稻米Cd质量比、土壤的基本理化性质、Cd总质量比、不同浸提态Cd质量比及欧共体标准物质局(European Community Bureau of Reference,BCR)形态。结果表明:稻米Cd质量比为0.01~0.51 mg/kg,土壤Cd质量比为0.17~3.15 mg/kg,稻米Cd富集系数为0.04~1.42;土壤Cd主要以弱酸态(40.5%)和还原态(37.1%)存在,二乙烯三胺五乙酸(diethylenetriaminepentaacetic acid,DTPA)浸提土壤Cd能力最强(15.6%);基于w(CaCl_(2)-Cd)构建的三次函数建立的回归模型可解释稻米Cd 57.4%方差,w(CaCl_(2)-Cd)可以作为表征水稻土壤Cd生物有效性的指标,基于水稻土壤Cd生物有效性可提高污染风险评价的科学性。展开更多
The interaction between a cationic dye Methylene Blue （MB） and an anionic surfactant sodium dodecyl sulfate （SDS） with the presence of Cd2＋ was investigated spectrophotometrically in a certain concentration range...The interaction between a cationic dye Methylene Blue （MB） and an anionic surfactant sodium dodecyl sulfate （SDS） with the presence of Cd2＋ was investigated spectrophotometrically in a certain concentration range. The spectrophotometric measurements of dye-metal ion-surfactant system were carried out. The results indicated that the SDS concentration had a significant influence on the dye spectrum, while the addition of Cd2~ hardly caused change of the maximum value of absorbance. According to this observation, we concluded that electrostatic and hydrophobic interaction between dye and surfactant occurred up to a certain level, and the homo-ions Cd2＋ almost exerted no effect on the dye-surfactant complexation, establishing a theoretical foundation for simultaneous removal of organic dye and heavy metal using foam fractionation. Meanwhile, the effects of their interaction on foam performance were investigated. The results showed that the addition of Cd2＋ favored the tendency to ameliorate foam properties just contrary to MB. The feasibility of foam separation for dye and heavy metal removal from simulated wastewater was also confirmed using a continuous foam fractionator. In the simultaneous removal process, with the initial SDS concentration ranging from 0.5 to 5.0 retool/L, the maximum removal efticiencies of MB and Cd2＋ were obtained as 99.69% and 99.61%, respectively. The enrichment ratios were reduced from 24.34 to 7.65 for MB and from 22.01 to 3.35 for Cd2＋.展开更多
The(2+1)-dimensional interaction of a Riemann wave propagating along the y-axis with a long wave along the x-axis is described by the space-time fractional Calogero-Degasperis(CD)and fractional poten-tial Kadomstev-Pe...The(2+1)-dimensional interaction of a Riemann wave propagating along the y-axis with a long wave along the x-axis is described by the space-time fractional Calogero-Degasperis(CD)and fractional poten-tial Kadomstev-Petviashvili(PKP)equation.It can be modeled according to the Hamiltonian structure,the lax pair with the non-isospectral problem,and the pain level property.The proposed equations are widely used in beachfront ocean and coastal engineering to describe the propagation of shallow-water waves,demonstrate the propagation of waves in dissipative and nonlinear media,and reveal the propagation of waves in dissipative and nonlinear media.In this paper,we have established further exact solutions to the nonlinear fractional partial differential equation(NLFPDEs),namely the space-time fractional CD and fractional PKP equations using the modified Rieman-Liouville fractional derivative of Jumarie through the two variable(G/G,1/G)-expansion method.As far as trigonometric,hyperbolic,and rational function so-lutions containing parameters are concerned,solutions are acquired when unique characteristics are as-signed to the parameters.Subsequently,the solitary wave solutions are generated from the solutions of the traveling wave.It is important to observe that this method is a realistic,convenient,well-organized,and ground-breaking strategy for solving various types of NLFPDEs.展开更多
To compare the effects of polysaccharide nucleic acid fraction of bacillus calmette guerin (BCG PSN) and thymopeptides on T lymphocytes of normal and immunosuppressed mice, CD4 + and CD8 + T lymphocyte subsets of...To compare the effects of polysaccharide nucleic acid fraction of bacillus calmette guerin (BCG PSN) and thymopeptides on T lymphocytes of normal and immunosuppressed mice, CD4 + and CD8 + T lymphocyte subsets of single nucleic cell in thymus, spleen and peripheral blood were detected successively by flow cytometry after application of BCG PSN and thymopeptides. Meanwhile, CD4 +/CD8 + ratio was also calculated. The results showed that both BCG PSN and thymopeptides could decrease the proportion of CD4 + CD8 + T lymphocyte subsets in the thymus, at the same time increase CD4 + T lymphocyte, CD8 +T lymphocyte proportion in the three tissues. The fluctuation in amplitude was greater in thymopeptides group than that in BCG PSN group. It is concluded that acting location of thymopeptides is in thymus, its stimulating action is stronger than that of BCG PSN, while BCG PSN not only accelerates the differentiation in thymus, but also has some direct stimulation to peripheral CD4 +T lymphocytes, and can maintain CD4 +/CD8 + ratio within normal range. So, BCG PSN is safer.展开更多
基金Supported by the National Science and Technology Pillar Program of China(No.2007BAD87B10)China Agriculture Research System(CARS-25-C-05)
文摘The effects of zinc （Zn） at different spray concentra- tions （0, 500, and 1 000 μmol · L-1 ） on the plant growth, the ac- tivities of antioxidant enzymes chemical forms of cadmium （Cd）, and the accumulation of Cd were studied and compared between two varieties, Shijichaotianjiao （SJCTJ） and Yanjiao425 （YJ425） of pepper （Capsicum annuum L.） in Cd-contaminated soil （Cd 10 mg @ kg-1 ）. The activities of catalase （CAT） and peroxidase （POD） were generally enhanced by Zn. However, superoxide dismutase （SOD） decreased. Addition of Zn decreased the ethanol-extract- able Cd, NaCl-extractable Cd, and acetic acid-extractable Cd in the fruit by 34.6%- 55.3%, 2.0%-17.7% and 0.4%-32.9%, and reduced the accumulation of Cd in fruit and plant total Cd by 12.8%- 68.6% and 9.0%-29.3% in both varieties, respectively.
基金financially supported by the National Science and Technology Support Program of China(No.2015BAD05B02)
文摘Cadmium(Cd)pollution in agricultural soils has exerted a serious threat due to continuous application of pesticides,fertilizers,and wastewater irrigation.The present study aimed to test the efficiency of KOH-modified and non-modified rice straw-derived biochar(KBC and BC,respectively)for reducing Cd solubility and bioavailability in Cd-contaminated soil.Cadmium-contaminated soil was incubated for 60 d with 15 and 30 g kg-1 BC and KBC.At the end of incubation,Cd mobility was estimated by the European Community Bureau of Reference sequential extraction and toxicity characteristic leaching procedure(TCLP),while bioavailability was determined using 1 molL-1 NH4NO3 extraction.The bioavailability risk index and bioaccessibility,assessed by a simple bioaccessibility extraction test,of Cd were used to examine the potential effects of Cd on living organisms.The results indicated that application of both KBC and BC significantly increased soil p H,cation exchange capacity,nutrients,and organic carbon.The soluble fraction of Cd was significantly decreased by 30.3%and 27.4%,respectively,with the addition of KBC and BC at 30 g kg-1 compared to the control(without biochar addition).Similarly,the bioaccessible Cd was significantly decreased by 32.4%and 25.2%,respectively,with the addition of KBC and BC at 30 g kg-1 compared to the control.In addition,both KBC and BC significantly reduced Cd leaching in the TCLP and NH4NO3-extractable Cd in the amended soil compared to the control.The reduction in Cd solubility and bioaccessibility by KBC and BC may be due to significant increases in soil pH and surface complexation.Overall,KBC at an application rate of 30 g kg-1 demonstrated positive results as soil amendment for Cd immobilization,and reduced bioaccessible Cd in contaminated soil.
文摘为遴选可有效表征农田土壤Cd生物有效性的指标,文章采集浙江某地20组稻米及其协同土壤,分析稻米Cd质量比、土壤的基本理化性质、Cd总质量比、不同浸提态Cd质量比及欧共体标准物质局(European Community Bureau of Reference,BCR)形态。结果表明:稻米Cd质量比为0.01~0.51 mg/kg,土壤Cd质量比为0.17~3.15 mg/kg,稻米Cd富集系数为0.04~1.42;土壤Cd主要以弱酸态(40.5%)和还原态(37.1%)存在,二乙烯三胺五乙酸(diethylenetriaminepentaacetic acid,DTPA)浸提土壤Cd能力最强(15.6%);基于w(CaCl_(2)-Cd)构建的三次函数建立的回归模型可解释稻米Cd 57.4%方差,w(CaCl_(2)-Cd)可以作为表征水稻土壤Cd生物有效性的指标,基于水稻土壤Cd生物有效性可提高污染风险评价的科学性。
基金supported by the National Natural Science Foundation of China (No. 50608028,50808073,50978088,51008121,51039001)the New Century Excellent Talents in University from the Ministry of Education of China (No. NCET-08-0180,NCET-08-0181)
文摘The interaction between a cationic dye Methylene Blue （MB） and an anionic surfactant sodium dodecyl sulfate （SDS） with the presence of Cd2＋ was investigated spectrophotometrically in a certain concentration range. The spectrophotometric measurements of dye-metal ion-surfactant system were carried out. The results indicated that the SDS concentration had a significant influence on the dye spectrum, while the addition of Cd2~ hardly caused change of the maximum value of absorbance. According to this observation, we concluded that electrostatic and hydrophobic interaction between dye and surfactant occurred up to a certain level, and the homo-ions Cd2＋ almost exerted no effect on the dye-surfactant complexation, establishing a theoretical foundation for simultaneous removal of organic dye and heavy metal using foam fractionation. Meanwhile, the effects of their interaction on foam performance were investigated. The results showed that the addition of Cd2＋ favored the tendency to ameliorate foam properties just contrary to MB. The feasibility of foam separation for dye and heavy metal removal from simulated wastewater was also confirmed using a continuous foam fractionator. In the simultaneous removal process, with the initial SDS concentration ranging from 0.5 to 5.0 retool/L, the maximum removal efticiencies of MB and Cd2＋ were obtained as 99.69% and 99.61%, respectively. The enrichment ratios were reduced from 24.34 to 7.65 for MB and from 22.01 to 3.35 for Cd2＋.
文摘The(2+1)-dimensional interaction of a Riemann wave propagating along the y-axis with a long wave along the x-axis is described by the space-time fractional Calogero-Degasperis(CD)and fractional poten-tial Kadomstev-Petviashvili(PKP)equation.It can be modeled according to the Hamiltonian structure,the lax pair with the non-isospectral problem,and the pain level property.The proposed equations are widely used in beachfront ocean and coastal engineering to describe the propagation of shallow-water waves,demonstrate the propagation of waves in dissipative and nonlinear media,and reveal the propagation of waves in dissipative and nonlinear media.In this paper,we have established further exact solutions to the nonlinear fractional partial differential equation(NLFPDEs),namely the space-time fractional CD and fractional PKP equations using the modified Rieman-Liouville fractional derivative of Jumarie through the two variable(G/G,1/G)-expansion method.As far as trigonometric,hyperbolic,and rational function so-lutions containing parameters are concerned,solutions are acquired when unique characteristics are as-signed to the parameters.Subsequently,the solitary wave solutions are generated from the solutions of the traveling wave.It is important to observe that this method is a realistic,convenient,well-organized,and ground-breaking strategy for solving various types of NLFPDEs.
文摘To compare the effects of polysaccharide nucleic acid fraction of bacillus calmette guerin (BCG PSN) and thymopeptides on T lymphocytes of normal and immunosuppressed mice, CD4 + and CD8 + T lymphocyte subsets of single nucleic cell in thymus, spleen and peripheral blood were detected successively by flow cytometry after application of BCG PSN and thymopeptides. Meanwhile, CD4 +/CD8 + ratio was also calculated. The results showed that both BCG PSN and thymopeptides could decrease the proportion of CD4 + CD8 + T lymphocyte subsets in the thymus, at the same time increase CD4 + T lymphocyte, CD8 +T lymphocyte proportion in the three tissues. The fluctuation in amplitude was greater in thymopeptides group than that in BCG PSN group. It is concluded that acting location of thymopeptides is in thymus, its stimulating action is stronger than that of BCG PSN, while BCG PSN not only accelerates the differentiation in thymus, but also has some direct stimulation to peripheral CD4 +T lymphocytes, and can maintain CD4 +/CD8 + ratio within normal range. So, BCG PSN is safer.
