THE ADSORPTION OF STARCHES ON PRESSURESENSITIVE ADHESIVE MATERIAL AND ITS IMPACT ON AGGLOMERATION

INTRODUCTIONIn our previous study [1], it was found that during high consistency pulping cationic starch could assist in the dispersion of pressure sensitive adhesive (PSA) particles, or sticky particles. Without the starch present the sticky particles were observed to agglomerate into large spherical particles. The cationic starch was shown to prevent agglomeration and cause the particles to form string-like shapes. Pulping the PSA in copy paper containing cationic starch also prevent…     

Elaboration and Properties of Nanocomposite Structures Based on Crown Modified Platinum Nanoparticles

1 Results This paper presents the development of platinum nanocomposites structures based on organically modified c.a.2 nm core platinum nanoparticles.The chemical modification of the 4-mercaptoaniline functionalized particles by various in coming molecules is evidenced and precisely quantified.The particles can be dissolved like molecules in various solvents depending on the features of the new crown and X-rays shows that the interparticle distance is affected by the crown modification.These platinum nanoparticles can be used to build up mixed LB films in well controlled way[1].The nanostructures are characterized by X-rays photoelectron[2] spectroscopy,IR spectroscopy,and small angle X-rays diffraction.The approach allows to build up well defined structures containing different particles in which electrical and electrochemical behaviour can be studied[3].The d.c.electrical properties are influenced by the crown modification as well as the electrochemical properties towards oxygen reduction.As a conclusion we believe that these systems are of particular interest to understand fundamental nanoscale events involved in electrocatalysis and could be of practical interest in practical fuel cells devices.     

Study on Soap-free P(MMA-EA-AA/MAA) Latex Particles With Narrow Size Distribution

1Introduction In the past decades, more and more studies have been focused on the synthesis of monodisperse particles with different diameter by special polymerization technique. In 1980' s, Ugelstad, et al[1] invented two-step swelling method to prepare monodisperse microsphere with large size more than 1 μm. In the following decade, Okubo and his coworkers[2] synthesized monodisperse crosslinked polymer particles above 3 μm using one-step dynamic swelling method. New method has been developed to produce particles more than 50 μm in diameter with a standard deviation of less than 2%[3]. Up to now, most of the monodisperse particles were usually prepared by polymerization of St in the presence of surfactants. In this presentation, sub-micro sized P (MMA-EA-AA/MAA) particles with narrow size distribution were prepared by seeded emulsion polymerization in the absence of any surfactant materials.     

Synthesis of HTEMPO Grafted the Surface of Attapulgite by γ-Glycidoxypropyltrimethoxysilane

1 Results Living free radical polymerization has undergone tremendous advancement in the past few years, particularly in the area of nitroxide mediated free radical polymerization. In 1980s, the use of nitroxyl free radicals such as 2,2,6,6-tetramethylpiperidinyl-1-oxyl(TEMPO) to moderate free radical polymerizations was first reported by Rizzardo,et al[1], more and more people began to interested in the polymerization methods which controlled by nitroxide stable free radicals. Recently, some people introduced 4-Hydroxy-2,2,6,6-tetramethylpiperidinyl -1-oxyl(HTEMPO) to inorganic particles and synthesis organic/inorganic hybrid materials[2]. In our study we grafted of HTEMPO onto the surface of attipulgite which can control the polymerization of styrene.     

Characterization of composite particles responsive to electric and magnetic fields

The multilayer particles with responses to electric and magnetic fields are a prerequisite for particles assembled under external fields. Three routes to produce particles responsive to electric and magnetic fields are presented in this article. The size and morphology, properties as well as the electric-magnetic responses of three kinds of particles are comparatively discussed. This will provide a useful basis for the control of the behavior of the particles in suspensions by external electric and magnetic fields.     

Variations of sulfur and carbon isotopes in seawater during the Doushantuo stage in late Neoproterozoic

The Doushantuo Formation of the Sinian System in the Yangtze area is the first sedimentary stratigraphic unit after the Neoproterozoic Snowball Earth event[1], named the Nantuo Glaciation in south China. There are not only phosphorite and manganese mineralized beds[2], but also a series of biome which represents the biological radiation in Neoproterozoic[3] found in this formation. It is important to study the palaeoenvironment and the early biological evolution implied in the Doushantuo …     

Alternative Models of Iron and Cobalt Catalysts for Ethylene Oligomerization and Polymerization

1 Results Great progresses have been made in the field of transition metal-based complexes as catalytic precursors for olefin oligomerization and polymerization,in which the core subjects will remain as "know and how" to develop novel catalysts both in academic and industrial consideration.The key advantage of iron and cobalt catalyst for ethylene polymerization is to produce vinyl-type polyethylenes.Therefore following the pioneering works of bis(imino) pyridyl iron and cobalt catalyst by Brookhart[1] and Gibson[2] in 1998,there have been many contributions toward their derivatives' complexes for the investigation of their catalytic behaviors.However,there are few examples successful good activity catalysts based upon new designed ligands such as monoiminopyridines[3],2-imino-1,10-phenanthrolines[4],2-benzimidazolylpyridines[5],2-quinoxalinyl-6-imino pyridines[6] and bimetallic complex[7].Those catalysts performed good to high catalytic activities towards ethylene oligomerization and polymerization,meanwhile most of them were first contributed with our efforts inspired by bis(imino)pyridyl metal catalyst.Herein we will present our results with designing pathways,and academic and industrial considerations.     

THE STUDY ON MECHANISM OF BINDER MIGRATION DURING COATING PROCESS

INTRODUCTIONBinders are the second most abundant component in the coating color after the pigment. Binders are added into coating colors to fulfill the following purposes, binding of pigment particles to each other, binding of pigment particles to base paper, adjusting of ink absorption, protecting of colloid, affecting stability and flowability of coating color [1]. Unlike uniform distribution in well prepared coating color suspension, binder distribution is nonuniform along the cross sec…     

Design and Application of Novel Dispersants for Coatings and Other System

1 Results Dispersants are defined as liquids or gases that can be added to a mixture to promote dispersion or to maintain dispersed particles in suspension. A good dispersant not only helps to provide good dispersion, but also good performance, stability and rheological properties. Therefore, dispersants are widely used in many applications such as coating, ink, electronic materials, plastics, and so on[1]. There are different ways to categorize the many dispersants available on the market. From a molecular weight point of view, dispersants can be categorized as low MW dispersants and high MW dispersants. This presentation mainly introduces the high MW dispersants, including their dispersion mechanism, functional design and applications.     

Stability and Robustness Analysis of an Adaptive Algorithm for Quasi-periodic Disturbances Rejection

IntroductionThere exist several approaches to tackle periodicdisturbance rejection problems. One approach is based onrepetitive or learning control principles[1], it has gainedsome popularity in various applications where periodicdisturbances rejection or repetitive tracking is required.These applications include the control of disk drives[2],rejection of load disturbances in steel casting process[3],eccentricity compensation in rolling[4] and so on. This typeof …     

Annual precipitation fields secular variation over global land areas for 1948—2000

In contrast to global temperature, fewer studies have been contributed to global precipitation. There are nu-merous efforts devoted to the problem, including Gruza[1], Diaz et al.[2], Bradley et al.[3], Vinnikov et al.[4] and Hulme[5], in which the global precipitation was addressed simply in the context of data in the 1980s, sometime be-fore that and the early 1990s[6—8]. More recently, studies have involved data around 1997 but on a local basis. Evi-dently, the problem of secular variatio…     

镶嵌纳米碳粒和硅粒氧化硅膜的电致红光发射研究

Luminescence study from the silicon oxide films embedded nm carbon particles (CSO) and nm silicon particles (SSO) is of great importance in integrated optoelectronics[1]. The pioneering work on electroluminescence (EL) from the SSO was reported by Dimaria et al[2]. They attributed the light emission to band-band recombination of electron-hole pairs in nanosize silicon particles. This model is referred to as the quantum confinement model. In this paper,we deposit CSO and SSO films onto p-type Si substrate and study comparatively visible EL from the Au/CSO/p-Si and Au/SSO/p-Si structures.     

Relationship between Arctic Oscillation and Pacific Decadal Oscillation on decadal timescale

The Pacific Decadal Oscillation (PDO) is one of the main modes to describe the climate variability in the North Pacific (NP)[1-5]. Recent studies showed that PDO is related to winter surface air temperature and precipitation over North America[3,6], the c…     

FTIR-ATR chamber for observation of efflorescence and deliquescence processes of NaClO4 aerosol particles on ZnSe substrate

NaClO4 aerosol particles with diameter of 5-20 microns are deposited on the ZnSe substrate. An FTIR-ATR chamber on the ZnSe substrate is set up to observe the structural changes of NaClO4 aerosol particles at crystallization relative humidity （CRH） and deliquescence relative humidity （DRH）. With the decrease of RH （relative humidity） from 96% to 24% in the efflorescence process, the absorbance of O-H stretching band of the aerosol solutions continuously decreases. A sudden decrease of the water peak is observed at RH20%, where solid particles form. Very small amount of residual interfacial water, with two weak peaks at 3602 and 3533 cm^-1, can still be resolved in the FTIR-ATR spectra of the solid particles. In the deliquescence process of the same sample, little spectral changes are observed when the value of RH varies from 5% to 29%. Before the abrupt increase of the O-H stretching band at the DRH of about RH46%, a pre-deliquescence process is observed, i.e. in the RH range between 33% and 46%, there is really a slow absorbance increase for the peak area of O-H stretching band. The O-H stretching band shows an arciform O-H en- velope, totally different from not only the FTIR-ATR spectra of ClO4^- solutions either under supersaturated state or in diluted state, but also the characteristic of the residually interfacial water discussed in the efflorescence process. Such kind of water is considered as pure water, indicating that small amount of water aggregates in the microspaces of solid aerosol particles due to the capillary cohesion effect. When the RH arrives at RH44%, two weak shoulders at 3384 and 3260 cm^-1 can be resolved, and the solid NaClO4 particles begin to be dissolved by increasing capillary cohesion water. The spectral characteristic of the v3-ClO4^- band also shows the transition from solid particles to mainly solvated ClO4^- ions.     

Effects of coagulation on submerged ultrafiltration membrane fouling caused by particles and natural organic matter （NOM）

Natural organic matter (NOM) and particles in source water are responsible for the majority of ultrafiltration (UF) membrane fouling that occurs during drinking water treatment. This study was conducted to (1) understand the UF membrane fouling phenomena caused by NOM and turbidity-causing particles and (2) investigate the effect of coagulation pretreatment on the alleviation of membrane fouling. In this study, kaolinite and humic acid (HA) were used to simulate the particles and NOM present in source water. The results revealed that the particles contributed to reversible fouling due to cake layer formation on the membrane surface, but that could be effectively reduced by increasing the frequency of physical backwashing. The results of the molecular weight (MW) distribution measurements, resin fractionation, SEM and FTIR analyses showed that HA primarily contributed to irreversible fouling. Taken together, the results of this study imply that the particles and NOM compounds present in source water may have different fouling behavior, and that particles may mitigate the irreversible fouling caused by HA. The addition of coagulant can lead to a higher rate of removal of large-sized hydrophobic compounds. Coagulation pretreatment can improve membrane performance and postpone membrane fouling development effectively, as well as retard the implementation of membrane chemical cleaning.     

Geochemistry and zircon U-Pb ages of granulite xenolith from Tuoyun basalts, Xinjiang： Implications for the petrogenesis and the lower crustal nature beneath the southwestern Tianshan

The continental lithosphere growth mainly includes the horizontal accretion at the plate boundaries and vertical accretion within the plate[1]. Mafic magmatic materials, as the products of crust-mantle interaction[2,3], became more and more important in studying the formation and evolu- tion of the lower crust. The previous geologic researcheson Tianshan, extending nearly 2500 km from east to west, and the neighbor area were mainly focused on the Paleozoic collision structure[4 ― 6], Mesozoi…     

DNS of the turbulence modulation by dispersed particles in compressible spatially developing two-phase jets

A new two-way coupled direct numerical simulation (DNS) method is developed to study the turbulence modulation in the compressible and spatial developing particle-laden turbulent jets with higher Reynolds number. The high-resolution solver is performed for the gas phase flow-field and the Lagrangian method is used to trace particles. It is found that the particles with Stokes number of 0.01and 50 advance the evolution of the coherent structures in the flow-field, but the particles with Stokes number of 1 delay it. All particles increase the turbulent kinetic energy and decrease the vorticity thickness, in which the particles with the Stokes number of 1 exhibit the maximum modulation. The jet velocity half-width and the decay of the streamwise mean velocity along the centerline are reduced by particles with Stokes number of 0.01 and 1. The momentum thickness is increased by particles and the larger the Stokes number is, the larger the momentum thickness is.     

Vector bundle constraint for particle swarm optimization and its application to active contour modeling

Active contour modeling (ACM) has been shown to be a powerful method in object boundary extraction. In this paper, a new ACM based on vector bundle constraint for particle swarm optimization (VBCPSO-ACM) is proposed. Different from the traditional particle swarm optimization (PSO), in the process of velocity update, a vector bundle is predefined for each particle and velocity update of the particle is restricted to its bundle. Applying this idea to ACM, control points on the contour are treated as particles in PSO and the evolution of the contour is driven by the particles. Meanwhile, global searching is shifted to local searching in ACM by decreasing the number of neighbors and inertia. In addition, the addition and deletion of particles on the active contour make this new model possible for representing the real boundaries more precisely. The proposed VBCPSO-ACM can avoid self-intersection during contour evolving and also extract inhomogeneous boundaries. The simulation results proved its great performance in performing contour extraction.     

Characterization and Preparation of Bimetallic Nanoparticles

1 Results Bimetallic particles in the nanometer size range are of substantial interest due to their vast applications in catalysis[1].The synthesis of bimetallic nanoparticles with definite size with a well-control over their nanostructure remains a challenging problem.Thus there exists a great demand for both synthesis and atomic level characterization of nanostructure of bimetallic nanoparticles (NPs).With the recent advent of high-intensity tunable sources of X-rays,now available at synchrotron radiation facilities worldwide,made X-ray absorption spectroscopy (XAS) a powerful tool for carrying out most of the structural aspects of the nano-sized catalysts.     

Reusing oxide-based pulverised fly ash and medical waste particles to develop electroless nickel composite coatings(Ni–P/fly ash and Ni–P/SiO_2–Al_2O_3)

Recycling and reusing materials from waste have become a nexus in the development of sustainable materials, leading to more balanced technologies. In this study, we developed a composite coating by co-depositing recycled ceramic particles, pulverised fly ash(PFA) and medical ceramics(MC), into a nickel–phosphorus matrix using a typical electroless plating process. Scanning electron microscopy(SEM) images indicated well-dispersed particles in the Ni–P matrix. However, compared with the MC particles, the PFA particles were distributed scantily with a lower content in the matrix, which could be due to the less impingement effect during the co-deposition. A modified microstructure with refined grains was obtained for the PFA-incorporated composite coating, as seen in the SEM micrograph. The X-ray diffraction result of the MC-incorporated composite coating showed the formation of Nix Siy phases in addition to the typical Ni3 P phases for the heattreated electroless Ni–P coatings. Upon heat treatment, the PFA-reinforced composite coating, due to a modified microstructure, exhibited a higher microhardness up to HK0.05 818, which is comparable to that of the traditional SiC particle-embedded composite coating(HK0.05 825).The findings can potentially open up a new strategy to further advance the green approach for industrial surface engineering.