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Ion coordination affinity and its application in mineral flotation
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作者 Hong-liang ZHANG Xin RAO +4 位作者 Chen-yang ZHANG Jian-hua CHEN Yang-ge ZHU Rong WANG Wei SUN 《Transactions of Nonferrous Metals Society of China》 2025年第10期3468-3479,共12页
The ion coordination affinities of the commonly found metal ions were evaluated using DFT calculations.The results indicate that the lowest unoccupied molecular orbital(LUMO)energy of metal ions correlates positively ... The ion coordination affinities of the commonly found metal ions were evaluated using DFT calculations.The results indicate that the lowest unoccupied molecular orbital(LUMO)energy of metal ions correlates positively with their binding energies with O(S)ligands,and some metal ions with various valence states also present different affinities.Besides,due to the steric hindrance effects,the mono-and hexa-coordinated metal ions may exhibit different affinities,and the majority of the studied hexa-coordinated metal ions exhibit oxophilicity.These affinity differences perfectly illustrate the activation flotation practice in which the oxyphilic ions are applied to activating oxide minerals,while thiophilic ions are applied to activating sulfide minerals. 展开更多
关键词 ion coordination affinity mineral flotation coordination chemistry density functional theory
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Biogeographic affinitypartly shapes woody plant diversity along an elevational gradient in subtropical forests
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作者 Zhaochen Zhang Fang Wang +13 位作者 Xiaoran Wang Mufan Sun Pu Zheng Jingchao Zhao Junhong Chen Min Guan Pengcheng Liu Xiaofan Shang Yaoshun Lu Qingpei Yang Qingni Song Lin Chen Quying Zhong Jian Zhang 《Plant Diversity》 2025年第5期784-792,共9页
The ecological and evolutionary mechanisms underlying montane biodiversity patterns remain unresolved.To understand which factors determined community assembly rules in mountains,biogeographic affinity that represents... The ecological and evolutionary mechanisms underlying montane biodiversity patterns remain unresolved.To understand which factors determined community assembly rules in mountains,biogeographic affinity that represents the biogeographic and evolutionary history of species should incorporate with current environments.We aim to address two following questions:1)How does plant taxonomic and phylogenetic diversity with disparate biogeographic affinitiesvary along the subtropical elevational gradient?2)How do biogeographic affinityand environmental drivers regulate the community assembly?We collected woody plant survey data of 32 forest plots in a subtropical mountain of Mt.Guanshan with typical transitional characteristics,including 250 woody plant species belonging to 56 families and 118 genera.We estimated the effects of biogeographic affinity,climate and soil properties on taxonomic and phylogenetic diversity of plant communities employing linear regression and structural equation models.We found that the richness of temperate-affiliated species increased with elevations,but the evenness decreased,while tropical-affiliatedspecies had no significantpatterns.Winter temperature directly or indirectly via biogeographic affinityshaped the assemblage of woody plant communities along elevations.Biogeographic affinityaffected what kind of species could colonize higher elevations while local environment determined their fitnessto adapt.These results suggest that biogeographic affinityand local environment jointly lead to the dominance of temperate-affiliated species at higher elevations and shape the diversity of woody plant communities along elevational gradients.Our findingshighlight the legacy effect of biogeographic affinityon the composition and structure of subtropical montane forests. 展开更多
关键词 Taxonomic diversity Phylogenetic diversity Biogeographic affinity Cold tolerance Phylogenetic niche conservatism
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An Adaptive Cubic Regularisation Algorithm Based on Affine Scaling Methods for Constrained Optimization
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作者 PEI Yonggang WANG Jingyi 《应用数学》 北大核心 2026年第1期258-277,共20页
In this paper,an adaptive cubic regularisation algorithm based on affine scaling methods(ARCBASM)is proposed for solving nonlinear equality constrained programming with nonnegative constraints on variables.From the op... In this paper,an adaptive cubic regularisation algorithm based on affine scaling methods(ARCBASM)is proposed for solving nonlinear equality constrained programming with nonnegative constraints on variables.From the optimality conditions of the problem,we introduce appropriate affine matrix and construct an affine scaling ARC subproblem with linearized constraints.Composite step methods and reduced Hessian methods are applied to tackle the linearized constraints.As a result,a standard unconstrained ARC subproblem is deduced and its solution can supply sufficient decrease.The fraction to the boundary rule maintains the strict feasibility(for nonnegative constraints on variables)of every iteration point.Reflection techniques are employed to prevent the iterations from approaching zero too early.Under mild assumptions,global convergence of the algorithm is analysed.Preliminary numerical results are reported. 展开更多
关键词 Constrained optimization Adaptive cubic regularisation affine scaling Global convergence
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Characteristics and Affinity of Tropical Flora in Southern China 被引量:7
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作者 朱华 M.C.Roos 《Forestry Studies in China》 CAS 2002年第1期18-24,共7页
The tropical flora in southern China is represented mainly by three regional flora, i.e. southern Yunnan (southwestern China), southwestern Guangxi (southwestern China) and Hainan Island (southern China). The floristi... The tropical flora in southern China is represented mainly by three regional flora, i.e. southern Yunnan (southwestern China), southwestern Guangxi (southwestern China) and Hainan Island (southern China). The floristic composition of each is concisely enumerated. Their geographical elements at generic level are analyzed. Furthermore, a comparison of floristic similarities between southern Yunnan and Hainan Island and Malay Peninsula and Brunei of western Malesia is made, based on existing regional flora treatments. The following is concluded: (1) The flora of southern China consists mainly of tropical floristic elements which contribute about 60% at the family level and more than 80 % at the generic level of its total flora. The dominant distribution type of the flora of southern China at the generic level is the tropical Asian distribution pattern. This reveals that the flora of southern China is of tropical nature with a strong tropical Asian affinity; (2) Most of the dominant families from the flora of southern China are also dominant in the Malesian flora. The floristic similarities between the regional flora of southern China and the regional flora of western Malesia are over 70% at the family level and more than 50% at the generic level. This suggests that the tropical flora of southern China belongs to the Malesian floristic region; (3) Situated at the northern margin of tropical Asia, on the other hand it is also obvious that the flora of southern China comprises less strictly tropical elements compared to the Malesian flora, and is consequently only a marginal type of the latter; (4) The close affinity of the flora of southern China to the Malesian flora can be explained by the geological history of southeast Asia. 展开更多
关键词 southern China FLORA floristic composition affinity
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Affinity Chromatography Purification of Recombinant Human Interleukin-6 from Its Fusion Protein with GST
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作者 吴蕾 甘一如 +1 位作者 林峰 黄鹤 《Transactions of Tianjin University》 EI CAS 2002年第2期106-109,共4页
Recombinant E.coli JM109, containing pHZ1818 plasmid which included the fused gene encoding human interleukin 6(IL 6), expressed a fusion protein with glutathion S transferase(GST). The fusion protein existed both... Recombinant E.coli JM109, containing pHZ1818 plasmid which included the fused gene encoding human interleukin 6(IL 6), expressed a fusion protein with glutathion S transferase(GST). The fusion protein existed both in the supernatant and inside the bacterial cell,but the insoluble protein had no biological activity and could not be refolded. The rotative speed of the shaker and the temperature of induction were optimized to maximize the expression of the soluble fusion protein. From the supernatant of the cell sonicates Glutathion Sephrose 4B affinity column chromatography was employed to isolate the fusion protein which could be purified to >80 0 0 in a single step. The yield of soluble GST IL 6 was about 10 mg per liter culture. The GST was site specifically cloven by 6 hours of treatment with thrombin and from the thrombin digest mixture IL 6 was purified by Q high performance ion exchange chromatography. From 1 liter of E.coli culture 2 mg refined IL 6 was obtained. The purified IL 6 had a purity of more than 95 0 0 and a biological activity of 1.02×10 8 IU/mg. 展开更多
关键词 affinity purification human interleukin 6 fusion protein GST
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一种利用熵函数和Affinity Propagation聚类的超图模型优化方法
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作者 刘建军 夏胜平 郁文贤 《中国图象图形学报》 CSCD 北大核心 2011年第3期442-448,共7页
属性图相似性阈值对类属超图(CSHG)模型的训练结果具有重要影响。在满足聚类准确性的条件下,利用定义的熵函数给出优化CSHG模型结构的相似性阈值,并得到初始优化的CSHG模型,进一步利用FTOG之间的相似性矩阵得到最简CSHG模型结构。另外,... 属性图相似性阈值对类属超图(CSHG)模型的训练结果具有重要影响。在满足聚类准确性的条件下,利用定义的熵函数给出优化CSHG模型结构的相似性阈值,并得到初始优化的CSHG模型,进一步利用FTOG之间的相似性矩阵得到最简CSHG模型结构。另外,利用亲缘传播聚类(affinity propagation clustering)方法去除FTOG聚类中的冗余属性图,最终得到最优的CSHG模型。实验结果表明,本方法是有效的。 展开更多
关键词 相似性图聚类 类属超图 熵函数 亲缘传播
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Affinity and fluorescent detection of surfactants/ssDNA and single-walled carbon nanotube 被引量:1
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作者 周姣 李娟萍 +2 位作者 聂钰洪 李继山 杨金凤 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第2期456-461,共6页
A new biosensor platform was explored for detection of surfactant based on fluorescence changes from single strand DNA (ssDNA) and single-walled carbon nanotubes (SWNTs). Thermodynamics assay was performed to valu... A new biosensor platform was explored for detection of surfactant based on fluorescence changes from single strand DNA (ssDNA) and single-walled carbon nanotubes (SWNTs). Thermodynamics assay was performed to value the stability of probe. The affinities of SWNT to five common surfactants (SDS, DBS, Triton X-100, Tween-20 and Tween-80) were investigated by real-time fluorescence method. The effects of Mg^2+ and pH on the fluorescence intensity of self-assembled quenched sensor were performed. The fluorescent emission spectra were used to measure the responses of self-assembled quenched fluorescent of ssDNA/SWNTs to different concentration surfactant(Triton X-100). The FAM-DNA wrapped SWNTs probe was stable in a wide temperature range (5 ℃ to 80℃). The binding strength of surfactants and single-stranded DNA (ssDNA) on SWNTs surfaces was shown as follows: Triton X-100〉DBS〉Tween-20〉Tween-80〉ssDNA〉SDS, and the optimized reaction conditions included pH 7.4 and 10 mmol/L Mg2+. The fluorescence of FAM-ssDNA wrapped SWNTs was proportionally recovered as a result of adding different concentrations of Triton X- 100, which realizes the quantitative detection of Triton X- 100. 展开更多
关键词 single-stranded DNA single-walled carbon nanotubes SURFACTANT fluorescent sensor affinity
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基于Affinity Propagation算法的半监督微博水军识别 被引量:3
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作者 林义钧 吴渝 李红波 《信息网络安全》 CSCD 北大核心 2022年第3期85-96,共12页
对微博网络空间中水军账户的识别研究,有助于清朗网络空间和维护社会安定。首先,文章针对微博水军不断进化、传统特征集无法覆盖现有水军特征,结合水军定义与原始特征,构造了新特征。然后,针对水军账户标注困难,无标注数据又没能充分利... 对微博网络空间中水军账户的识别研究,有助于清朗网络空间和维护社会安定。首先,文章针对微博水军不断进化、传统特征集无法覆盖现有水军特征,结合水军定义与原始特征,构造了新特征。然后,针对水军账户标注困难,无标注数据又没能充分利用的问题,提出了一种基于Affinity Propagation算法的半监督微博水军识别方法(APDHW)。该方法通过在Affinity Propagation算法中引入欧氏距离Radius阈值,再结合支持向量机分类算法,实现对微博水军识别。通过多组实验对比及实证研究,结果表明文章所提的微博水军识别方法在牺牲少量算法时间的情况下得到较好的识别效果,提升了水军识别的准确率和召回率。 展开更多
关键词 微博水军 affinity Propagation 半监督学习 水军识别
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基于Affinity Propagation聚类方法的图像检索技术在数字图书馆中的应用 被引量:4
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作者 万洁 《计算机与现代化》 2008年第8期116-119,共4页
随着数字图书馆包含的内容逐渐丰富,数字图像也越来越多。为了有效地检索这些图像,迫切需要一种效率更高的检索方法。目前的基于内容的图像检索算法在检索时间和效率上都还不能满足这一需求。本文采用最新提出的Af-finity Propagation... 随着数字图书馆包含的内容逐渐丰富,数字图像也越来越多。为了有效地检索这些图像,迫切需要一种效率更高的检索方法。目前的基于内容的图像检索算法在检索时间和效率上都还不能满足这一需求。本文采用最新提出的Af-finity Propagation聚类方法和颜色-形状直方图特征,提出一种新的检索方法应用到数字图书馆进行图像检索。经过试验证明在查准率、查全率和检索时间上均有较大的提高。 展开更多
关键词 图像检索 数字图书馆 affinity Propagation CLUSTER 颜色.形状直方图
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Local and global approaches of affinity propagation clustering for large scale data 被引量:15
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作者 Ding-yin XIA Fei WU +1 位作者 Xu-qing ZHAN Yue-ting ZHUANG 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2008年第10期1373-1381,共9页
Recently a new clustering algorithm called 'affinity propagation' (AP) has been proposed, which efficiently clustered sparsely related data by passing messages between data points. However, we want to cluster ... Recently a new clustering algorithm called 'affinity propagation' (AP) has been proposed, which efficiently clustered sparsely related data by passing messages between data points. However, we want to cluster large scale data where the similarities are not sparse in many cases. This paper presents two variants of AP for grouping large scale data with a dense similarity matrix. The local approach is partition affinity propagation (PAP) and the global method is landmark affinity propagation (LAP). PAP passes messages in the subsets of data first and then merges them as the number of initial step of iterations; it can effectively reduce the number of iterations of clustering. LAP passes messages between the landmark data points first and then clusters non-landmark data points; it is a large global approximation method to speed up clustering. Experiments are conducted on many datasets, such as random data points, manifold subspaces, images of faces and Chinese calligraphy, and the results demonstrate that the two ap-proaches are feasible and practicable. 展开更多
关键词 CLUSTERING affinity propagation Large scale data Partition affinity propagation Landmark affinity propagation
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Nano CuO/g-C_3N_4 sheets-based ultrafiltration membrane with enhanced interfacial affinity,antifouling and protein separation performances for water treatment application 被引量:5
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作者 Thanigaivelan Arumugham Reshika Gnanamoorthi Amimodu +1 位作者 Noel Jacob Kaleekkal Dipak Rana 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2019年第8期57-69,共13页
To improve the interfacial affinity and antifouling properties of polyphenylsulfone(PPSU)membrane, nano CuO/g-C3 N4(g-CN) sheets were synthesized via facile calcination route as one pot synthesis method. The uniformly... To improve the interfacial affinity and antifouling properties of polyphenylsulfone(PPSU)membrane, nano CuO/g-C3 N4(g-CN) sheets were synthesized via facile calcination route as one pot synthesis method. The uniformly assembled nanohybrid fillers, CuO on g-CN sheets were confirmed by using XRD, TEM, EDX and FTIR analysis. The non-solvent induced phase inversion technique was used to fabricate the nanohybrid ultrafiltration(UF)membranes by doping different concentration(0.5–1 wt.%) of nano CuO/g-C_3 N_4(g-CN)sheets within the PPSU matrix. The results of contact angle, atomic force microscopy,energy-dispersive X-ray spectroscopy reveal that surface structure and physico-chemical properties of nanohybrid membrane plays lead role in solute interaction and rejection compared to bare membrane, M0. Furthermore, the interfacial affinity of membrane was explored in detail via surface free energy, spreading coefficient, wetting tension and reversible work of adhesion analysis. Nanohybrid UF membrane, with 0.5% of the filler(M1)displayed remarkable permeation flux of 202, 131 L/m2/hr for pure water and protein solution, respectively while maintaining a high protein rejection(96%). Moreover, the exceptional dispersion of the nanosheets in the polymer matrix enhanced FRR(79%) and decreased the overall resistance of M1 compared to the pristine membrane(M0). Overall results suggest that the incorporation of nano sheets is a facile modification technique which improves the comprehensive membrane performance and holds a great potential to be further explored for water treatment. 展开更多
关键词 ULTRAFILTRATION membrane Copper oxide Graphitic carbon NITRIDE INTERFACIAL affinity ANTIFOULING Protein removal
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Dyes with high affinity for polylactide 被引量:5
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作者 Liang He Shu Fen Zhang +2 位作者 Bing Tao Tang Li Li Wang Jin Zong Yang 《Chinese Chemical Letters》 SCIE CAS CSCD 2007年第9期1151-1153,共3页
Attempts were made to develop dyes with high affinity for polylactide as an alternative to the existent commercial disperse dyes. The dyes synthesized according to the affinity concept of dye to polylactide exhibited ... Attempts were made to develop dyes with high affinity for polylactide as an alternative to the existent commercial disperse dyes. The dyes synthesized according to the affinity concept of dye to polylactide exhibited excellent dyeing properties on polylactide compared with the commercial disperse dyes. 展开更多
关键词 Dye affinity POLYLACTIDE Dyeing properties
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Male spike strobiles with Gnetum affinity from the Early Cretaceous in western Liaoning,Northeast China 被引量:5
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作者 Shuang-Xing GUO jin-Geng SHA +1 位作者 Li-Zeng BIAN Yin-Long QIU 《Journal of Systematics and Evolution》 SCIE CSCD 北大核心 2009年第2期93-102,共10页
A fossil with Gnetum affinity was found in the Jianshangou Member (Barremian Age) of the Yixian Formation (Lower Cretaceous Epoch) of the Jehol Group in western Liaoning, northeastern China. The single fossil spec... A fossil with Gnetum affinity was found in the Jianshangou Member (Barremian Age) of the Yixian Formation (Lower Cretaceous Epoch) of the Jehol Group in western Liaoning, northeastern China. The single fossil specimen is represented by both elongate-cylindrical male spike strobiles which borne within a nodal bract of cauliflorous branch. The spike strobiles have apparent nodes, invisible internodes, and numerous verticillate involucral collars. The microsporangiate units within involucral collars are not seen. The male spike strobiles with verticillate involucral collars occur exclusively in Gnetum; hence, the fossil strobiles are attributed to a new taxon, Khitania columnispicata gen. & sp. nov., being closely related to Gnetum. The general isotopic dating suggests an age of Barremian, ca. 125-122 million years (Myr) ago for the Jianshangou Member. The palaeoecological and palaeoclimatic inference based on the compositions of flora and fauna, and lithological characters of the fossil locality suggests that the fossil plants grew in a subtropical mesophytic forest and under a warmer climate. The remains of male spike strobiles are the first record of gnetalean macrofossil. It documents the evolution of the distinct gnetoid morphology and indicates a wider range of distribution of Gnetaceae in the Early Cretaceous than present day. 展开更多
关键词 BIOGEOGRAPHY Early Cretaceous Gnetum affinity male spike strobiles northeastern China.
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Synthesis of a New Series of Bone Affinity Compounds 被引量:3
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作者 Ying WANG Hong CHEN +6 位作者 Zong Ming WAN Mao Sheng CHENG Xue Chao WANG Guo Liang CONG Sheng JING Zi Ping YAN Bo WU 《Chinese Chemical Letters》 SCIE CAS CSCD 2006年第3期310-312,共3页
A new series of bone affinity compounds were synthesized by linking chrysophanol with 5-fluorouracil derivatives. Their bone affinity was established by hydroxyapative (HA) affinity experiment in vitro, and their cy... A new series of bone affinity compounds were synthesized by linking chrysophanol with 5-fluorouracil derivatives. Their bone affinity was established by hydroxyapative (HA) affinity experiment in vitro, and their cytostatic effects were shown by the MTT assay. 展开更多
关键词 CHRYSOPHANOL 5-FLUOROURACIL bone affinity antitumor.
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DFT Calculations of the Ionization Potential and Electron Affinity of Alaninamide 被引量:3
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作者 张慧 卢金凤 +2 位作者 张淑芳 唐珂 周正宇 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2007年第11期1373-1379,共7页
Adiabatic and vertical ionization potentials (IPs) mad valence electron affmities (EAs) of alaninamide in gas phase have been detennined using density functional theory (BLYP, B3LYP, B3P86) methods with 6-311+... Adiabatic and vertical ionization potentials (IPs) mad valence electron affmities (EAs) of alaninamide in gas phase have been detennined using density functional theory (BLYP, B3LYP, B3P86) methods with 6-311++G(d, p) basis set, respectively. IPs and EAs of alaninamide in solutions have been calculated at the B3LYP/6-311++G(d, p) level. Five possible conformers of alaninamide and their charged states have been optimized employing density functional theory B3LYP method with 6-311++(d, p) basis set, respectively. 展开更多
关键词 alaninamide onization potential electron affinity vertical ionization potentials
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Preparation of Chitosan-coated Nylon Membranes and their Application as Affinity Membranes 被引量:2
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作者 Wei SHI Feng Bao ZHANG Guo Liang ZHANG 《Chinese Chemical Letters》 SCIE CAS CSCD 2005年第8期1085-1088,共4页
Chitosan-coated nylon membranes which possess a large number of reactive groups of-CH2OH and -NH2 were prepared by coupling chitosan onto the nylon membrane. Then polylysine as ligand was also immobilized onto the com... Chitosan-coated nylon membranes which possess a large number of reactive groups of-CH2OH and -NH2 were prepared by coupling chitosan onto the nylon membrane. Then polylysine as ligand was also immobilized onto the composite membranes by 1, 1'-carbonyl-diimidazole activation to prepare affinity membranes for bilirubin adsorption. The results showed that these membranes exhibited high binding affinity capacities for bilirubin and the adsorption isotherm fitted the Freundlich model well. 展开更多
关键词 CHITOSAN affinity membrane BILIRUBIN adsorption.
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A new series of emodin derivatives with bone affinity 被引量:2
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作者 Hong Chen Ying Wang +3 位作者 Ling Leng Mao Sheng Cheng Peng Fei Yu Jing Ze Zhang 《Chinese Chemical Letters》 SCIE CAS CSCD 2007年第2期141-144,共4页
A new series of bone affinity compounds were synthesized by linking emodin with 5-fluorouracil derivatives. Their bone affinities were established by hydroxyapative (HA) affinity experiment in vitro, and their cytosta... A new series of bone affinity compounds were synthesized by linking emodin with 5-fluorouracil derivatives. Their bone affinities were established by hydroxyapative (HA) affinity experiment in vitro, and their cytostatic effects were shown by the MTT assay. 展开更多
关键词 EMODIN 5-FLUOROURACIL Bone affinity ANTITUMOR
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Multiple Model Soft Sensor Based on Affinity Propagation, Gaussian Process and Bayesian Committee Machine 被引量:33
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作者 李修亮 苏宏业 褚健 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2009年第1期95-99,共5页
Presented is a multiple model soft sensing method based on Affinity Propagation (AP), Gaussian process (GP) and Bayesian committee machine (BCM). AP clustering arithmetic is used to cluster training samples acco... Presented is a multiple model soft sensing method based on Affinity Propagation (AP), Gaussian process (GP) and Bayesian committee machine (BCM). AP clustering arithmetic is used to cluster training samples according to their operating points. Then, the sub-models are estimated by Gaussian Process Regression (GPR). Finally, in order to get a global probabilistic prediction, Bayesian committee mactnne is used to combine the outputs of the sub-estimators. The proposed method has been applied to predict the light naphtha end point in hydrocracker fractionators. Practical applications indicate that it is useful for the online prediction of quality monitoring in chemical processes. 展开更多
关键词 multiple model soft sensor affinity propagation Gaussian process Bayesian committee machine
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Implications from protein uptake kinetics onto dextran-grafted Sepharose FF coupled with ion exchange and affinity ligands 被引量:10
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作者 Aiying Xue Linling Yu Yan Sun 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2017年第7期906-910,共5页
Our previous studies have reported the presence of "chain delivery" effects of protein adsorption onto ion exchangers with polymer-grafted ion-exchange groups, such as dextran-grafted and poly(ethylenimine)-... Our previous studies have reported the presence of "chain delivery" effects of protein adsorption onto ion exchangers with polymer-grafted ion-exchange groups, such as dextran-grafted and poly(ethylenimine)-modified Sepharose gels. However, it is unclear if the "chain delivery" occurs on affinity adsorption with specific interactions. This work is designed to address this issue. A dextran-grafted Sepharose gel was prepared, and then the matrix was modified using diethylaminoethyl, a typical ion-exchange group, or octapeptide(FYCHWQDE), an affinity ligand for human immunoglobulin G(h Ig G) to prepare ion-exchange or affinity adsorbents, respectively.Results of h Ig G adsorption showed that the uptake rate represented by the effective diffusivity of h Ig G onto the dextran-grafted ion exchangers was obviously enhanced by the dextran grafting, indicating the presence of"chain delivery" of the bound proteins on the charged groups on the dextran chains. By contrast, the effective diffusivity of h Ig G changed little as ligand density increased on the dextran-grafted FYCHWQDE adsorbents.Their adsorption capacities decreased and effective diffusivities were not accelerated by the dextran grafting.Thus, this work clarified that grafted dextran could not accelerate h Ig G uptake rate on the affinity resins, or in other words, chain delivery did not occur on the specific interaction-based affinity adsorption. 展开更多
关键词 Dextran-grafted adsorbent Ion exchange chromatography affinity chromatography lmmunoglobulin G KINETICS
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