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Degradation Mechanism of Cationic Red X-GRL by Ozonation 被引量:14
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作者 Wei Rong ZHAO Xin Hua XU +1 位作者 Hui Xiang SHI Da Hui WANG 《Chinese Chemical Letters》 SCIE CAS CSCD 2003年第12期1309-1312,共4页
The degradation mechanism of Cationic Red X-GRL was investigated when the intermediates, the nitrate ion and the pH were analyzed in the ozonation. The degradation of the Cationic Red X-GRL includes the de-auxochrome... The degradation mechanism of Cationic Red X-GRL was investigated when the intermediates, the nitrate ion and the pH were analyzed in the ozonation. The degradation of the Cationic Red X-GRL includes the de-auxochrome stage, the decolour stage, and the decomposition of fragment stage. During the degradation process, among the six nitrogen atoms of Cationic Red X-GRL, one is transferred into a nitrate ion, one becomes the form of an amine compound, and the rest four are transformed into two molecules of nitrogen. In the course of the ozonation of Cationic Red X-GRL, the direct attack of ozone is the main decolour effect. 展开更多
关键词 OZONATION cationic red X-GRL MECHANISM INTERMEDIATES DYE decolourization.
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Kinetics of the Reaction Between Ozone and Cationic Red X-GRL 被引量:6
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作者 赵伟荣 史惠祥 汪大翚 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2003年第4期388-394,共7页
The ozonation of Cationic Red X-GRL in a semi-batch reactor was studied with variation of the gas flow rate, initial Cationic Red X-GRL concentration, temperature, and pH value. By the evaluation of the liquid mass tr... The ozonation of Cationic Red X-GRL in a semi-batch reactor was studied with variation of the gas flow rate, initial Cationic Red X-GRL concentration, temperature, and pH value. By the evaluation of the liquid mass transfer coefficient, the interfacial area, and the stoichiometric ratio between ozone and Cationic Red X-GRL, the rate constants and the kinetic regime of the reaction between ozone and Cationic Red X-GRL were investigated by applying the experimental data to a model based on the film mass transfer theory. The results obtained support a second order overall reaction, first order with respect to both ozone and dye, and the rate constants were correlated by a modified Arrhenius Equation of temperature and pH value with activation energy of 18.06kJ·mol-1. Hatta number of the reaction was found to be between 0.026 and 0.041, it indicates that the reaction occurs in the liquid bulk, corresponding to the slow kinetic regime. 展开更多
关键词 OZONATION cationic red X-GRL reaction kinetics DYE mass transfer
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Automated Red Deer Algorithm with Deep Learning Enabled Hyperspectral Image Classification
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作者 B.Chellapraba D.Manohari +1 位作者 K.Periyakaruppan M.S.Kavitha 《Intelligent Automation & Soft Computing》 SCIE 2023年第2期2353-2366,共14页
Hyperspectral(HS)image classification is a hot research area due to challenging issues such as existence of high dimensionality,restricted training data,etc.Precise recognition of features from the HS images is importa... Hyperspectral(HS)image classification is a hot research area due to challenging issues such as existence of high dimensionality,restricted training data,etc.Precise recognition of features from the HS images is important for effective classification outcomes.Additionally,the recent advancements of deep learning(DL)models make it possible in several application areas.In addition,the performance of the DL models is mainly based on the hyperparameter setting which can be resolved by the design of metaheuristics.In this view,this article develops an automated red deer algorithm with deep learning enabled hyperspec-tral image(HSI)classification(RDADL-HIC)technique.The proposed RDADL-HIC technique aims to effectively determine the HSI images.In addition,the RDADL-HIC technique comprises a NASNetLarge model with Adagrad optimi-zer.Moreover,RDA with gated recurrent unit(GRU)approach is used for the identification and classification of HSIs.The design of Adagrad optimizer with RDA helps to optimally tune the hyperparameters of the NASNetLarge and GRU models respectively.The experimental results stated the supremacy of the RDADL-HIC model and the results are inspected interms of different measures.The comparison study of the RDADL-HIC model demonstrated the enhanced per-formance over its recent state of art approaches. 展开更多
关键词 Hyperspectral images image classification deep learning adagrad optimizer nasnetlarge model red deer algorithm
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Adsorption of 2,4-dinitrophenol and 2,4-dichlorophenol on Cationic Surfactant Modified Red Soil 被引量:3
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作者 廖敏 《Chinese Journal Of Geochemistry》 EI CAS 2004年第4期301-308,共8页
Adsorption isotherms of 2,4-dinitrophenol and 2,4-dichlorophenol on hexadecyltrimethylammonium (HDTMA) bromide modified red soil under different ionic strength, divalent cation Cu 2+ or different pH conditions were st... Adsorption isotherms of 2,4-dinitrophenol and 2,4-dichlorophenol on hexadecyltrimethylammonium (HDTMA) bromide modified red soil under different ionic strength, divalent cation Cu 2+ or different pH conditions were studied. All the adsorption isotherms were well fitted to the Freundlich equation. The adsorption capacities of 2,4-dinitrophenol or 2,4-dichlorophenol were dramatically enhanced by HDTMA treatment of red soil. The increase of ionic strength and the addition of divalent heavy metal cation Cu 2+ significantly enhanced the adsorption of 2,4-dinitrophenol or 2,4-dichlorophenol on the HDTMA-modified red soil. Adsorption capacities of HDTMA-modified red soil for 2,4-dinitrophenol and 2,4-dichlorophenol gradually increased with decreasing pH in the aqueous phase. 展开更多
关键词 2 4-二硝基酚 2 4-二氢氯化 红土 阳离子表面活性剂
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Characteristics of Cationic Red X-GRL Adsorption by Diatomite Tailings 被引量:1
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作者 郑仁基 高惠民 +2 位作者 GUAN Junfang REN Zijie TIAN Jingjing 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2017年第5期1038-1047,共10页
As secondary mineral resources, diatomite tailings(DT) got from the Linjiang region of China were prepared and characterized by SEM, XRF and XRD. Mono-factor experiments were carried out to investigate the effects o... As secondary mineral resources, diatomite tailings(DT) got from the Linjiang region of China were prepared and characterized by SEM, XRF and XRD. Mono-factor experiments were carried out to investigate the effects of the operation factor, including contact time, adsorbent concentration, initial p H value of the dye solutions, adsorption temperature and initial concentration of cationic Red X-GRL(X-GRL) on the adsorption of X-GRL. The adsorption kinetics, isotherms, thermodynamics and mechanisms for X-GRL were also studied. It was efficient for DT to adsorb X-GRL from aqueous solutions, and it was even discovered to have higher adsorptivity for X-GRL than diatomite concentrate(DC) in our previous test. The adsorption processes fit very well with the pseudo-second-order model and the Langmuir isotherm equation. In addition, various thermodynamic parameters, such as standard Gibbs free energy(ΔG°), standard enthalpy(ΔH°) and standard entropy(ΔS°) have been calculated. From thermodynamic studies, it was seen that the adsorption was spontaneous and endothermic. The main driving forces of the physical adsorption on DT are electrostatic attraction. The reason why DT showed higher adsorptivity for X-GRL than DC was that there were more clay mineral particles within, which has a remarkable ability of dye adsorption due to its high surface area. DT as a cheap absorbent for X-GRL removal would replace or partially replace the activated carbon. 展开更多
关键词 diatomite tailings cationic red X-GRL adsorption
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Interaction between Cationic Surfactants and Bromopyrogallol Red as well as Its Application for the Sensitive and Selective Determination of Mo in Mo/W Binary Mixtures
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作者 Xi Rong HUANG Shu Hua HAN +2 位作者 Wen Juan ZHANG Yong Quan YIN Gui Ying XU (Department of Chemistry, Shandong University, Jinan 250100) 《Chinese Chemical Letters》 SCIE CAS CSCD 1997年第6期523-526,共4页
Prior to formation of the micelles of cationic surfactant (CSF), bromopyrogallol red (BPR) could exist in the forms of both monomer and oligomer After that, however, only BPR monomer existed. Nonionic surfactant OP-10... Prior to formation of the micelles of cationic surfactant (CSF), bromopyrogallol red (BPR) could exist in the forms of both monomer and oligomer After that, however, only BPR monomer existed. Nonionic surfactant OP-10 favoured the oligomerization of BPR monomer. The mixed micellar media prepared by mixing CSF and OP-10 in an appropriate ratio could be used for the sensitive and selective determination of Mo in Mo/W binary mixtures. 展开更多
关键词 well MO Interaction between cationic Surfactants and Bromopyrogallol red as well as Its Application for the Sensitive and Selective Determination of Mo in Mo/W Binary Mixtures
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珠三角赤红壤常年菜地土壤肥力质量评价
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作者 宁建凤 李彤 +3 位作者 曾瑞锟 姚建武 陈勇 梁紫薇 《草业学报》 CSCD 北大核心 2024年第5期25-40,共16页
赤红壤是广东省地带性土壤,研究位于该地带性土壤的菜地肥力变化特征,以客观评价耕作施肥管理的科学性,助力耕地质量保护与提升。在广东省珠三角地区广州市、江门市、肇庆市、惠州市惠阳区选取了89个蔬菜常年种植菜地,测定了耕层(0~20 ... 赤红壤是广东省地带性土壤,研究位于该地带性土壤的菜地肥力变化特征,以客观评价耕作施肥管理的科学性,助力耕地质量保护与提升。在广东省珠三角地区广州市、江门市、肇庆市、惠州市惠阳区选取了89个蔬菜常年种植菜地,测定了耕层(0~20 cm)土壤理化指标,利用第二次全国土壤普查养分分级标准和内梅罗综合指数法分析评价土壤肥力状况。珠三角赤红壤常年菜地土壤质地以壤土、砂质壤土、粉壤土为主,分别占比46.1%、23.6%和19.1%;pH 5.83,呈微酸性;有机质含量23.83 g·kg-1,为中等水平;阳离子交换量8.67 cmol(+)·kg-1,为中等偏下水平;全氮(N)、全磷(P)、全钾(K)含量分别为1.19、1.47、12.53 g·kg-1,其中全氮和全磷含量均属中等水平,全钾含量为中等偏下水平;有效态养分中碱解氮、有效磷、速效钾含量分别为135.24、120.24、222.48 mg·kg-1,属于丰富(碱解氮和速效钾)和极丰富水平(有效磷)。内梅罗综合指数法评价结果显示,珠三角赤红壤常年菜地土壤综合肥力指数为1.69,属良好等级。相比第二次全国土壤普查广东省赤红壤普查结果,土壤全钾含量不同程度降低,pH值、有机质、全氮、碱解氮含量均不同程度提高,增幅分别为16.6%、23.5%、38.4%和62.5%;阳离子交换量、全磷、有效磷和速效钾含量大幅增加,增幅分别达1.29、6.00、65.80和3.07倍,其中土壤有效磷累积较为普遍。全氮和全磷的年均累积量分别为8.46、32.31 mg·kg-1,碱解氮、有效磷和速效钾年均累积量分别为1.20、3.04、4.30 mg·kg-1。总体上,经过近40年耕种,珠三角赤红壤常年菜地肥力水平不同程度改善,土壤pH由酸性改善为微酸性,阳离子交换性能、有机质、全氮含量提升1个等级,碱解氮和有效钾含量提升2个等级,全磷和有效磷含量分别提升3和5个等级。各肥力指标总体上由原来的极度缺乏至中等偏下状态改善为目前的中等偏下至极丰富水平,总体肥力状况良好。在实施蔬菜有机无机肥配施技术基础上,合理施用氮、钾肥,降低磷肥投入量,可以进一步提升珠三角赤红壤区菜地地力水平,维持土壤资源的可持续利用。 展开更多
关键词 赤红壤 土壤肥力 常年菜地 阳离子交换量 耕地质量
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植物补光用In^(3+)掺杂Zn_(3)Ga_(2)Ge_(2)O_(10)∶Cr^(3+)远红光发光材料的性能研究
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作者 白琼宇 王春浩 《人工晶体学报》 CAS 北大核心 2024年第9期1568-1575,共8页
采用高温固相法制备了Cr^(3+)掺杂的远红光荧光粉,并通过引入In^(3+)对Zn_(3)Ga_(2)Ge_(2)O_(10)∶Cr^(3+)发光特性进行了调控。通过XRD对Zn_(3)(Ga_(1-x)In_(x))_(2)Ge_(2)O_(10)∶2%Cr^(3+)(摩尔分数)的晶体结构进行了分析。利用室温... 采用高温固相法制备了Cr^(3+)掺杂的远红光荧光粉,并通过引入In^(3+)对Zn_(3)Ga_(2)Ge_(2)O_(10)∶Cr^(3+)发光特性进行了调控。通过XRD对Zn_(3)(Ga_(1-x)In_(x))_(2)Ge_(2)O_(10)∶2%Cr^(3+)(摩尔分数)的晶体结构进行了分析。利用室温荧光光谱和热释光光谱分析了Zn_(3)(Ga_(1-x)In_(x))_(2)Ge_(2)O_(10)∶2%Cr^(3+)的发光特性,其发射光谱由^(4)T_(2)(^(4)F)→^(4)A_(2)和^(2)E→^(4)A_(2)跃迁的705、721 nm两发光峰叠加而成。随着Zn_(3)(Ga_(1-x)In_(x))_(2)Ge_(2)O_(10)∶2%Cr^(3+)中In^(3+)掺杂浓度增加,材料发射光谱呈现展宽的现象,这是Cr^(3+)所处晶体场环境的改变导致了晶体场劈裂程度的变化。光谱展宽后荧光材料的发光特性与植物中光敏色素吸收谱更加匹配,因此其有望应用于植物照明领域。此外,随着In^(3+)掺杂浓度增加,荧光材料表现出红色长余辉现象,并且余辉时间与In^(3+)掺杂浓度有关。 展开更多
关键词 荧光粉 Zn_(3)Ga_(2)Ge_(2)O_(10)∶Cr^(3+) In^(3+)掺杂 远红光 阳离子替代 植物补光
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Study on Exchangeable Cation Determining Base Saturation Percentage of Soil in South China
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作者 Anqi Wang Xiangzhen Kong +2 位作者 Xiaodong Song Bing Ju Decheng Li 《Agricultural Sciences》 2020年第1期17-26,共10页
Base saturation percentage (BSP) is an important soil chemical index in soil fertility and soil taxonomy. However, it is still unclear what exchangeable cation dominates BSP of soil in south China. Therefore, in this ... Base saturation percentage (BSP) is an important soil chemical index in soil fertility and soil taxonomy. However, it is still unclear what exchangeable cation dominates BSP of soil in south China. Therefore, in this study, the data of BSPs and exchangeable H+, Al3+, Ca2+, Mg2+, K+ and Na+ of 109 and 45 horizon samples of 50 and 28 soil species in red soil and yellow soil groups in the Database of Chinese Soil Species were used to explore further the characteristics of BSPs and exchangeable cations as well as the correlation between BSPs and exchangeable cations. The results showed that the concentrations of exchangeable cations in both red soil and yellow soil groups were in an order of Al3+ (4.55 ± 1.47 and 4.22 ± 1.2 cmol(+)/kg) > Ca2+ (0.32 ± 0.21 and 0.36 ± 0.24 cmol(+)/kg) > H+ (0.23 ± 0.13 and 0.19 ± 0.10 cmol(+)/kg) > K+ (0.16 ± 0.09 and 0.16 ± 0.11 cmol(+)/kg) > Mg2+ (0.13 ± 0.09 and 0.11 ± 0.08 cmol(+)/kg) > Na+ (0.08 ± 0.06 and 0.11 ± 0.06 cmol(+)/kg). For red soil group, Al3+ concentration was significantly higher than those of other exchangeable cations, Ca2+ and H+ concentrations were significantly higher than those of K+, Mg2+ and Na+;while for yellow soil group, Ca2+, H+ and K+ concentrations were significantly higher than those of Mg2+ and K+. BSP of red soil group was codetermined by Ca2+, Al3+, Mg2+ and Na+, with the contributions of 33.81%, 19.82% and 14.49%, respectively;while BSP of yellow soil group was codetermined by Al3+, Ca2+, Mg2+, K+ and Na+, with the contributions of 24.91%, 21.55%, 19.91% and 14.21%, respectively. A higher concentration of exchangeable cation does not mean the higher importance of the cation to soil BSP. 展开更多
关键词 Base Saturation PERCENTAGE (BSP) Exchangeable cationS Correlation red SOIL Yellow SOIL South China
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中国共产党精神谱系视域下新疆红色资源育人现状及对策探究
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作者 安玫 热米拉·斯力木 张婷 《喀什大学学报》 2023年第4期76-85,共10页
中国共产党精神谱系具有丰富的内涵和时代价值,是红色资源的源头根脉和精神内核。论文以中国共产党精神谱系为视角,调研新疆红色资源育人现状,发现存在认识不够深入,权威性研究成果不多,内涵有待于拓展、文化价值有待于提升,红色资源的... 中国共产党精神谱系具有丰富的内涵和时代价值,是红色资源的源头根脉和精神内核。论文以中国共产党精神谱系为视角,调研新疆红色资源育人现状,发现存在认识不够深入,权威性研究成果不多,内涵有待于拓展、文化价值有待于提升,红色资源的传播、影响受限于时代性、地域性,红色资源育人途径和方式创新性不足、育人体系不完备等问题,据此提出深入学习宣传中国共产党精神谱系、全面挖掘新疆的红色资源,凝练源于中国共产党精神谱系的新疆红色资源精神特质,分类系统梳理、扩大传播面和影响力以及构建“三位一体”协同育人体系的思路和措施。 展开更多
关键词 中国共产党 精神谱系 新疆红色资源 育人现状 对策
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Brilliant red X-3B uptake by a novel polycyclodextrin-modified magnetic cationic hydrogel:Performance,kinetics and mechanism 被引量:2
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作者 Junyi Li Yili Wang +4 位作者 Xiaomin Dou Haotian Hao Shuoxun Dong Xia Shao Yanchun Deng 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2020年第3期264-276,共13页
A novel polycyclodextrin-modified magnetic cationic hydrogel(PCD-MCH) was developed and its performance,kinetics and mechanism for the removal of reactive brilliant red X-3B(X-3B) were studied.The results showed that ... A novel polycyclodextrin-modified magnetic cationic hydrogel(PCD-MCH) was developed and its performance,kinetics and mechanism for the removal of reactive brilliant red X-3B(X-3B) were studied.The results showed that the zeta-potential of PCD-MCH was 32.8 to16.7 mV at pH 3.0-10.5.The maximum X-3B adsorption capacity of PCD-MCH was2792.3 mg/g.The adsorption kinetics could be well-described by the Weber-Morris model and the homogeneous surface diffusion model(HSDM).Diffusion stages corresponding to surface or film diffusion,intra-particle or wide mesopore diffusion,and narrow mesopore/micropore diffusion occurred at 0-120,120-480 and 480-1200 min,respectively.The latter two diffusion stages were rate-controlling for X-3B adsorption kinetics.At the initial X-3B concentration of 600 mg/L,the diffusion coefficient(Ds) and external mass transfer coefficient in the liquid phase(kF) were 3x10^-11 cm^2/min and 4.68 x 10^-6 cm/min,respectively.X-3B approaching the center of PCD-MCH particles could be observed at 360 min.At the end of the third diffusion stage,the Cp at q/qe=0 was 45.20 mg/L,which was close to the homogeneous Cp value of 46 mg/L along the radius of PCD-MCH particles.At pH 3.0-10.0,PCD-MCH showed stable X-3B adsorption capacities.After five regeneration-reuse cycles,the residual adsorption capacity of regenerated PCD-MCH was higher than 892.7 mg/g.The corresponding adsorption mechanism was identified as involving electrostatic interactions,cyclodextrin cavities and hydrogen bonds,of which cyclodextrin cavities showed prominent capture performance towards dye molecules through the formation of inclusion complexes. 展开更多
关键词 Adsorption Polycyclodextrin-magnetic cationic HYDROGEL Reactive BRILLIANT red X-3B Homogeneous surface diffusion model(HSDM) Electrostatic interactions Inclusion complexes
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TiO_2/膨润土纳米复合光催化剂降解偶氮染料的研究 被引量:56
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作者 孙振世 陈英旭 +2 位作者 柯强 杨晔 袁骏 《环境科学学报》 CAS CSCD 北大核心 2003年第1期129-133,共5页
采用酸性溶胶法合成TiO2 膨润土纳米复合光催化剂 ,并研究其光催化降解阳离子偶氮染料 .X射线衍射 (XRD)分析表明 ,TiO2 膨润土纳米复合物的d0 0 1衍射角为 9 0 6° .该复合催化剂具有较高的光催化降解有机污染物的活性 ,随着光... 采用酸性溶胶法合成TiO2 膨润土纳米复合光催化剂 ,并研究其光催化降解阳离子偶氮染料 .X射线衍射 (XRD)分析表明 ,TiO2 膨润土纳米复合物的d0 0 1衍射角为 9 0 6° .该复合催化剂具有较高的光催化降解有机污染物的活性 ,随着光照时间的延长 ,阳离子红GTL的特征峰 490 5nm强度逐渐减弱 ,最后它的特征峰可彻底消失 ,GTL的偶氮键是最活跃的化学键 ,它易于被氧化断键 .该复合催化剂的催化活性受溶液的pH影响较大 ,在中性和碱性条件下其光催化活性更强 .适量的过氧化氢可以加速光催化氧化反应 ,但过量的H2 O2 却抑制了羟基自由基的生成 ,从而使H2 O2 的利用效率下降 ,在本实验条件下其最佳用量是 6mmol L . 展开更多
关键词 TiO2/膨润土纳米复合光催化剂 偶氮染料 催化活性 纳米复合物 废水处理
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模拟酸雨对浙东北红壤中盐基离子和铝的淋失影响研究 被引量:34
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作者 戎秋涛 杨春茂 徐文彬 《环境科学学报》 CAS CSSCI CSCD 北大核心 1997年第1期32-38,共7页
通过对浙江省东北部杭州至宁波地区两个红壤剖面的模拟酸雨淋溶实验研究表明,随着时间的延续,盐基离子的淋失浓度会在某一时期出现一个峰值,该峰值的出现与酸雨的pH值并不简单相关,Al3+的淋失浓度只是在酸雨pH值=2.5左... 通过对浙江省东北部杭州至宁波地区两个红壤剖面的模拟酸雨淋溶实验研究表明,随着时间的延续,盐基离子的淋失浓度会在某一时期出现一个峰值,该峰值的出现与酸雨的pH值并不简单相关,Al3+的淋失浓度只是在酸雨pH值=2.5左右才显著增高并在淋出液pH=4.0时有一个阈值;经pH=2.5—3.0模拟酸雨10余年降水量的淋溶,红壤中淋出液的pH值下降不超过0.8. 展开更多
关键词 酸雨 红壤 盐基离子 淋溶 浙江东北部
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共存阳离子(Ca、Zn、K)对土壤镉有效性的影响 被引量:18
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作者 宋正国 徐明岗 +2 位作者 丁永祯 孙楠 唐世荣 《农业环境科学学报》 CAS CSCD 北大核心 2009年第3期485-489,共5页
采用盆栽与吸附试验,研究了镉污染赤红壤上,施用相同摩尔浓度的钙、钾与锌对小油菜生物量、镉吸收量及土壤镉吸附的影响。结果表明,低和高镉污染赤红壤上,施用锌明显增加小油菜地上部生物量,较对照分别增产21.1%和7.82%。不同阳离子(钠... 采用盆栽与吸附试验,研究了镉污染赤红壤上,施用相同摩尔浓度的钙、钾与锌对小油菜生物量、镉吸收量及土壤镉吸附的影响。结果表明,低和高镉污染赤红壤上,施用锌明显增加小油菜地上部生物量,较对照分别增产21.1%和7.82%。不同阳离子(钠、钙、钾和锌离子)共存改变土壤吸附镉能力的程度不同,与钠体系相比,钙、钾和锌体系中土壤镉吸附量分别降低65.6%、72.0%和96.9%,共存离子降低土壤镉吸附量的次序为锌离子>钾离子和钙离子,锌离子的影响最为明显。高镉污染赤红壤上,钙和钾使小油菜吸镉量分别增加5.5%和14.4%,低于低镉污染赤红壤上钙和钾使小油菜吸镉的增加量(分别为16.6%和19.6%);锌明显降低小油菜吸镉量,高和低镉污染赤红壤上,较对照分别减少45.8%和35.0%。3种阳离子与镉共存时,对土壤镉生物有效性的影响差异取决于竞争吸附与竞争吸收的大小,其机制有待进一步探讨。 展开更多
关键词 共存离子 小油菜 赤红壤 有效性
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甘蓝皮生物吸附去除水中的阳离子染料 被引量:30
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作者 孙影芝 龚仁敏 +2 位作者 张小平 刘慧君 杨超 《中国环境科学》 EI CAS CSCD 北大核心 2005年第B06期61-64,共4页
研究了低值的地产甘蓝皮生物吸附去除水中阳离子染料的可行性,选用了亚甲蓝、中性红、吖啶橙3种染料,研究了各种操作条件对吸附的影响,如吸附剂量、染料浓度、吸附剂粒径、pH值、吸附时间等,确定了最佳吸附条件.结果表明,初始pH值大于4,... 研究了低值的地产甘蓝皮生物吸附去除水中阳离子染料的可行性,选用了亚甲蓝、中性红、吖啶橙3种染料,研究了各种操作条件对吸附的影响,如吸附剂量、染料浓度、吸附剂粒径、pH值、吸附时间等,确定了最佳吸附条件.结果表明,初始pH值大于4,3种染料去除率高.吸附在12h达到平衡.吸附等温线符合Langmuir或Freundlich模式,吸附过程符合Langergren准一级动力学方程.由此表明甘蓝皮是一种优良的处理阳离子染料废水的生物材料. 展开更多
关键词 甘蓝皮 生物吸附 阳离子染料 亚甲蓝 中性红 吖啶橙
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模拟酸雨对阳离子在土体内迁移的影响 被引量:25
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作者 王代长 蒋新 +3 位作者 贺纪正 赵振华 孙磊 郜红建 《地球化学》 CAS CSCD 北大核心 2004年第1期46-52,共7页
利用室内模拟酸雨的土柱实验,研究了在红壤表土施用钾肥后酸雨对不同土层交换性阳离子迁移的影响。结果表明,在不同土体深度,表土直接受酸沉降的淋溶,也是最容易发生酸化的土层,pH2.5酸雨淋溶后,表土pH值下降到3.5~4.2,这是铝的缓冲范... 利用室内模拟酸雨的土柱实验,研究了在红壤表土施用钾肥后酸雨对不同土层交换性阳离子迁移的影响。结果表明,在不同土体深度,表土直接受酸沉降的淋溶,也是最容易发生酸化的土层,pH2.5酸雨淋溶后,表土pH值下降到3.5~4.2,这是铝的缓冲范围,且土壤交换性H+和Al3+含量的增加显示出土壤对酸沉降的缓冲效率和缓冲能力的急剧减弱;pH4.5酸雨淋溶后,A和B层土壤pH值上升了0.3~0.5,其机理与SO2-4的专性吸附释放OH-有关;表土施用钾肥后,K+交换土壤表面的H+和Al3+,引起土壤交换性H+和Al3+向下迁移;不同pH值的酸性降雨引起土壤中交换性阳离子向下迁移和淋失的程度也有明显的差异,pH2.5酸雨淋溶后土壤溶液中钾的含量高于pH4.5酸雨淋溶的,但交换性钾含量低于后者;pH2.5和pH4.5酸雨淋溶后交换性钙的淋失量分别占原土的50%~70%和20%~40%,这表明酸雨淋洗会导致养分库的损耗,造成土壤养分贫瘠。 展开更多
关键词 酸雨 阳离子 迁移 红壤 缓冲机制
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无机阳离子对TiO_2光催化降解染料的影响 被引量:15
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作者 唐玉朝 胡春 王怡中 《环境化学》 CAS CSCD 北大核心 2003年第4期364-368,共5页
考察了 6种无机阳离子对P 2 5TiO2 光催化降解染料的影响 ,结果发现 ,Cu2 +,Mn2 +和Ni2 +对光催化反应有强烈的抑制作用 ,Ca2 +,Mg2 +和Al3+对光催化反应速率无明显的负影响 .经X光电能谱 (XPS)的分析 ,确定锰离子以氧化物的形式沉积在... 考察了 6种无机阳离子对P 2 5TiO2 光催化降解染料的影响 ,结果发现 ,Cu2 +,Mn2 +和Ni2 +对光催化反应有强烈的抑制作用 ,Ca2 +,Mg2 +和Al3+对光催化反应速率无明显的负影响 .经X光电能谱 (XPS)的分析 ,确定锰离子以氧化物的形式沉积在氧化钛表面 ,使催化剂不可逆的中毒 .Cu2 +和Ni2 展开更多
关键词 无机阳离子 TIO2 光催化 降解 染料废水 影响 废水处理
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偶氮染料的臭氧氧化机理研究 被引量:31
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作者 史惠祥 赵伟荣 汪大翚 《浙江大学学报(工学版)》 EI CAS CSCD 北大核心 2003年第6期734-738,共5页
在3.5L半序批式反应器中进行了阳离子红X-GRL偶氮染料的臭氧氧化实验.用GC/MS定性和GC半定量等方法确定了该染料在臭氧氧化过程中各中间产物的出现次序及浓度变化,结合臭氧与染料反应的化学计量比、反应过程中溶液pH的下降和NO3-的生成... 在3.5L半序批式反应器中进行了阳离子红X-GRL偶氮染料的臭氧氧化实验.用GC/MS定性和GC半定量等方法确定了该染料在臭氧氧化过程中各中间产物的出现次序及浓度变化,结合臭氧与染料反应的化学计量比、反应过程中溶液pH的下降和NO3-的生成,得出了染料的臭氧氧化机理可分为三个阶段,即:助色基脱落、最大吸收峰紫移阶段;生色基分解、染料脱色阶段;无色中间产物进一步降解成有机酸、醛、酮及烷烃等有机小分子阶段.确定了染料分子中6个氮的转化路径,即:其中4个氮原子转化为2分子N2,另外2个氮原子分别转化为1分子有机氮化合物和1分子NO-3.染料的臭氧氧化以直接氧化为主. 展开更多
关键词 偶氮染料 臭氧氧化机理 脱色机理 中间产物 阳离子红X-GRL 印染废水
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模拟氮沉降下南方针叶林红壤的养分淋溶和酸化 被引量:18
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作者 孙本华 胡正义 +2 位作者 吕家珑 周丽娜 徐成凯 《应用生态学报》 CAS CSCD 北大核心 2006年第10期1820-1826,共7页
以中国科学院红壤生态实验站林草生态试验区针叶林红壤为研究对象,在恒温(20℃)条件下,通过大土柱(直径10cm、高60cm),8个月间隙性淋溶试验模拟研究了不同氮输入量(0、7.8、26和52mgN/月/柱)对针叶林红壤NO3-、NH4+、H+和土壤盐基离子(C... 以中国科学院红壤生态实验站林草生态试验区针叶林红壤为研究对象,在恒温(20℃)条件下,通过大土柱(直径10cm、高60cm),8个月间隙性淋溶试验模拟研究了不同氮输入量(0、7.8、26和52mgN/月/柱)对针叶林红壤NO3-、NH4+、H+和土壤盐基离子(Ca2+、Mg2+、K+、Na+)淋溶以及土壤酸化的影响.结果表明,土壤交换态盐基总量、Ca2+和Mg2+淋溶量随氮输入量的增加而增加,土壤交换态Na+和K+则无明显影响.4种N输入处理的土壤交换态盐基总量净淋溶(淋溶出的盐基与淋洗液累计输入的盐基之差)分别占土壤交换性盐基总量的13.9%、18.6%、31.8%和57.9%,土壤交换态Ca2+净淋溶分别占土壤交换性Ca2+总量的19.6%、25.8%、45.3%和84.8%,土壤交换态Mg2+净淋溶分别占土壤交换性Mg2+总量的4.4%、6.1%、10.9%和17.1%.随氮输入量增加,表层土壤pH值逐渐下降,4种N输入处理的表层土壤pH(KCl)分别为3.85、3.84、3.80和3.75;随氮输入量增加,淋溶液中无机氮、NO3-和H+逐渐增加.氮沉降可促进针叶林红壤的有机氮矿化,加速养分淋失和土壤酸化. 展开更多
关键词 针叶林 红壤 氮沉降 盐基离子 养分淋溶 土壤酸化
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黄铁矿催化类Fenton反应处理阳离子红X-GRL废水 被引量:27
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作者 冯勇 吴德礼 马鲁铭 《中国环境科学》 EI CAS CSCD 北大核心 2012年第6期1011-1017,共7页
基于对天然矿物黄铁矿进行SEM、EDS表征的基础上,以黄铁矿为非均相类Fenton催化剂,以偶氮染料阳离子红X-GRL为目标污染物,考察了催化剂双氧水用量、溶液初始pH值、阳离子红X-GRL初始浓度、反应时间等因素对染料脱色效果的影响.结果表明,... 基于对天然矿物黄铁矿进行SEM、EDS表征的基础上,以黄铁矿为非均相类Fenton催化剂,以偶氮染料阳离子红X-GRL为目标污染物,考察了催化剂双氧水用量、溶液初始pH值、阳离子红X-GRL初始浓度、反应时间等因素对染料脱色效果的影响.结果表明,在H2O2浓度为26.6mg/L、矿用量1g/L、溶液初始pH值6.4左右的条件下,反应2min后,染料脱色率达95%左右.进行了黄铁矿在水溶液中的酸性氧化实验并且考察了Fe2+、SO42-浓度及溶液pH随矿重复利用次数的变化规律.初次使用的黄铁矿具有很强的酸性氧化特性,反应过程中伴随着大量Fe2+、SO42-及H+的溶出.染料的快速脱色主要是均相Fenton反应作用的结果.黄铁矿作为一种新的催化剂大大提高了类Fenton反应的催化活性,而且该新型类Fenton反应能克服传统Fenton反应适用pH范围小的局限性,拓展了Fenton反应在废水处理中的应用. 展开更多
关键词 黄铁矿 类FENTON 阳离子红X-GRL 催化氧化
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