Electrochemical probing of selective haemoglobin binding in hydrogel-based molecularly imprinted polymers

An electrochemical method has been developed for the probing of hydrogel-based molecularly imprinted polymers (HydroMIPs) on the surface of a glassy carbon electrode. HydroMIPs designed for bovine haemoglobin selectivity were electrochemically characterised and their rebinding properties were monitored using cyclic voltammetry. The electrochemical reduction of bovine oxyhaemoglobin (BHb) in solution was observed to occur at −0.460 V vs (Ag/AgCl) in 150 mM phosphate buffer solution (PBS). When the protein was selectively bound to the MIP, the electrochemical reduction of oxyhaemoglobin could be observed at a similar peak potential of −0.480 V vs (Ag/AgCl). When analysing the non-imprinted control polymer (NIP) interfaced at the electrode, which contained no protein, the peak reduction potential corresponded to that observed for dissolved oxygen in solution (−0.65 V vs (Ag/AgCl)). MIP and NIP (in the absence of protein) were interfaced at the electrode and protein allowed to diffuse through the polymers from the bulk solution end to the electrode. It was observed that whereas NIP exhibited a protein response within 10 min of protein exposure, up to 45 min of exposure time was required in the case of the MIP before a protein response could be obtained. Our results suggest that due to the selective nature of the MIP, BHb arrival at the electrode via diffusion is delayed by the MIP due to attractive selective interactions with exposed cavities, but not the NIP which is devoid of selective cavities.     

An emerging approach for the targeting analysis of dimethoate in olive oil: The role of molecularly imprinted polymers based on photo-iniferter induced “living” radical polymerization

This study concerns the first attempt to prepare molecularly imprinted polymers for the selective recognition of dimethoate using an iniferter polymerization technique (Inif-MIP). The synthesized polymers were fully characterized. SEM micrographs show a large accessibility to the binding sites with a significant improvement in MIP morphology. Inif-MIPs displayed high adsorption capacity (Q = 5.3 mg g⁻¹). The selectivity of this imprinting system was also assessed by means of cross-selectivity assays and the results obtained show that Inif-MIP displays a high selectivity for dimethoate, whereas some structural analogues (omethoate, malathion and methidathion) are poorly retained (6.3–28.7%) or not retained at all (fenthion). Inif-MISPE methodology was implemented by packing Inif-MIPs particles into a Solid Phase Extraction (SPE) cartridge and the loading, washing and eluting steps were optimized. The suitability of this sample preparation technique was demonstrated, as concentrations of dimethoate close to the tolerated maximum residue limits in the olive oil samples could be satisfactorily analyzed with good precision and accuracy. Some remarkable characteristics, like the sorbent reusability (at least 20 cycles without the lost of selectivity), low solvent consumption, reduced sample handling and, moreover higher recovery rates reaching 88% could be ascribed to the Inif-MISPE methodology.     

含掺合料混凝土氯盐侵蚀后孔结构特征试验研究

对氯盐侵蚀后不同掺合料混凝土进行了压汞试验,从细观角度研究了掺合料对混凝土孔结构特征的影响。结果表明:单掺粉煤灰20%、35%和50%以及单掺矿粉35%和50%,均有效降低了混凝土的总孔隙率,单掺50%矿粉时总孔隙率最小;单掺粉煤灰20%、35%以及单掺矿粉35%和50%,均有效降低了混凝土的总孔面积,单掺50%矿粉时总孔面积最小;单掺粉煤灰20%、35%和50%以及单掺矿粉35%和65%,均有效降低了混凝土的平均孔径,且单掺65%矿粉时平均孔径最小;单掺粉煤灰35%和50%及单掺矿粉65%时,最可几孔径较基准混凝土明显减小,混凝土孔径得到细化;单掺粉煤灰35%和50%以及单掺矿粉35%和65%均使多害孔、有害孔比例减小,且粉煤灰掺量在50%左右,有害孔比例最小,混凝土抗渗性能最好。     

Selective Separation of Thorium Using Ion Imprinted Chitosan‐Phthalate Particles via Solid Phase Extraction

Abstract

We have studied a new method for the preparation of Th(IV)‐imprinted chitosan‐phthalate particles, which can considerably enhance the adsorption capacity and selectivity of thorium ions. In this study, chitosan‐phthalate was used as the complexing monomer, Th(IV) as template, epichlorohydrin as crosslinking agent. Initially, chitosan was modified with phthalic anhydrides and complex formation occured between carboxylic acid functional groups and Th(IV) ions. Secondly, particles were crosslinked with epichlorohydrin. After the removal of Th(IV) ions, thorium solid phase extraction (SPE) on the Th(IV) ion‐imprinted particles from aqueous solutions containing their different amounts, selectivity study of thorium versus other interfering metal ions mixture which are Fe³⁺, La³⁺, and Mn²⁺ and distribution and selectivity coefficients were reported here. A comparison of the selectivity coefficient of Th(IV)‐imprinted chitosan‐phthalate particles with the selectivity coefficient of non‐imprinted polymers showed that the imprinted matrix for Th(IV)/Fe(III), Th(IV)/La(III) and Th(IV)/Mn(II) was 8.35, 8.75 and 10.81 times greater than non‐imprinted matrix, respectively.     

Maximum Intensity Projection Using Splatting in Sheared Object Space

In this paper we present a new Maximum Intensity Projection (MIP) algorithm which was implemented employing splatting in a shear-warp context. This algorithm renders a MIP image by first splatting each voxel on two intermediate spaces called "worksheet" and "shear image". Then, the maximum value is evaluated between worksheet and shear image. Finally, shear image is warped on the screen to generate the result image. Different footprints implementing different quality modes are discussed. In addition, we introduced a line encoded indexing speed-up method to obtain interactive speed. This algorithm allows for a quantitative, predictable trade-off between interactivity and image quality.     

线性规划软件包GLPK的分析与应用

GLPK是一个求解大规模的线性规划问题(LP)、混合整数规划问题(MIP)以及相关问题的自由软件包。该文分析TGLPK的算法结构与数值计算等多方面的实现技术，并应用于解决NP-hard的调度问题。数值结果表明GLPK是研究LP和MIP问题强有力的工具。     

The Pore Structure and Hydration Performance of Sulphoaluminate MDF Cement

1　IntroductionReducingporositycouldimprovethestrengthofma terials ,butitisnotenoughthatthechangeofthestrengthofthematerialsisonlysubjectedtothechangeofporosi ty .Thereforetheporedistributionconceptisintroduced .Weeventhinkthattherelationbetweentotalporos…     

分层移动IP网络的自适应移动性管理

移动IP(mobile IP,MIP)使主机在移动过程中不需改变IP地址便可连续访问Internet,其主要缺点是主机在移动过程中需要频繁地进行绑定更新,产生的信令开销较大。为降低移动IPv6的信令开销,IETF(Internet engineering task force)提出了分层移动IPv6(hierarchical mobile IPv6,HMIPv6)协议。基于HMIPv6,提出了一种自适应的分层移动性管理方案。这种方案采用模糊逻辑,根据移动主机的移动次数及移动性管理代价,动态选取MAP(mobility anchor point)并调整MAP区域所管辖的接入路由器个数。仿真分析表明,所提出的方案的代价优于固定MAP区域的移动性管理方案。     

MIP工艺在重油催化裂化装置的工业应用

对中国石化北京燕山分公司80万t/a重油催化裂化装置提升管反应部分进行了多产异构烷烃(MIP)工艺改造,并应用了RMIP-1型专用催化剂。运行及标定结果表明:与改造前相比,汽油、柴油产率分别降低了2.42,2.55个百分点,原料油转化率、丙烯收率分别增加了0.37,0.62个百分点,汽油研究法辛烷值(RON)增加了0.3个单位,汽油中的烯烃质量分数降低了13.69个百分点。     

Analysis of Pore Structures and Their Relations with Strength of Hardened Cement Paste

Three cement samples were prepared, including OPC consisted of 100wt%^ portland cement. PFA consisted of 70wt% portland cement and 30wt% fly-ash, and CA consisted of 70wt% portland cement and 30wt% modified fly ash. The strength of hardened cement paste of these samples was tested and their pore structures were determincd by a mercury intrusion porosimeter. Moreover, the data of the pore structures of three samples were comprehensively analyzed. The relations between the pore structures and the compressive strength of the three samples were studied. The experimental results show that the relations between the porosity determined by the mercury intrusion porosimeter and the compressive strength are not notable, and the total pore surface area, the average pore diameter and the median pore diameter could be used to explain the difference of the strength of the tested samples.