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Small extracellular vesicles (sEVs) have been increasingly recognized as circulating biomarkers and prognosticators for disease diagnosis. However, the clinical applications of sEVs are seriously limited by the lack of a robust and easy scale-up isolation technique. Herein, the feasibility of a polyphenol-metal three-dimensional (3D) network for label-free sEV isolation was explored. As a proof-of-concept, with tannic acid (TA) as the polyphenolic ligand and Fe(III) as the coordinated metal, the TA-Fe(III) 3D network coating mesoporous silica beads (SiO

High performance liquid chromatography-mass spectrometry is one of the most commonly used strategies for lipid analysis. The development of versatile chromatographic stationary phases to meet the increasing demands for separation of complex lipids is very important. Styrene-maleic acid (SMA) copolymer is an amphiphilic polymer, which has been proven to have the ability to solubilize lipid molecules of various structures. In this study, styrene-maleic anhydride copolymer coated silica was first prepared by the thiol-ene click reaction. With L-cysteine hydrochloride or dodecanol as the post-modification reagents, Sil-SMA-amino acid and Sil-SMA-dodecanol stationary phase materials were further successfully fabricated via nucleophilic ring-opening reaction. The Fourier-transform infrared, thermogravimetric analysis, and elemental analysis results confirmed the two stationary phase materials were successfully prepared. Furthermore, both the Sil-SMA-dodecanol column and the Sil-SMA-amino acid column possessed reversed-phase/hydrophilic interaction/ion exchange mixed-mode retention mechanisms. The column efficiency of the Sil-SMA-derivatives columns reached 77,300 N/m. Based on the mixed-mode retention characteristics, the Sil-SMA-derivatives columns achieved both the lipid classes and species separation via a single column. The Sil-SMA-amino acid column was further successfully used to separate lipid extract from gastric cancer cell membrane. All these results demonstrated that the SMA-based stationary phase materials have a good potential for use in lipid separation.

There is a large and growing demand for the vigorous development of new high performance liquid chromatography stationary phases in order to solve complex phospholipids separation. Herein, phosphonium-based ionic liquid trioctyl(allyl)phosphonium bromide ([P888Allyl]Br) was first synthesized with trioctylphosphine and allyl bromide. With [P888Allyl]Br as the polymerizable monomer, polymerized phosphonium ionic liquid functionalized silica microsphere (PIL@SiO2) was further synthetized via click chemistry reaction. Significantly, based on the inherent amphiphilic nature of the introduced [P888Allyl]Br, the packed PIL@SiO2 column displayed hydrophilic/hydrophobic mixed-mode retention mechanisms. The PIL@SiO2 column can achieve separation of nucleic acid bases and nucleosides, sulfonamides, amides and anilines with excellent selectivity in a shorter separation time. The column efficiency reached 109,700 N/m for 2-iodoacetamide. One of the important characteristics of the PIL@SiO2 column is that both phospholipid classes and species can be efficiently separated via the same column, outperforming that of the commercial amino column. Furthermore, the application potential of the PIL@SiO2 column was further verified via separation of phospholipids extracted from soy lecithin. The proposed PIL@SiO2 column provides a promising candidate for separation of complex phospholipid samples.

ZnMgAl-LDHs were prepared by co-precipitation method and modified with starch to transform the structure for the adsorption property improvement. Samples were characterized by XRD, BET, SEM and FT-IR. Effect of starch soluble dosage, initial MO concentration and absorbent dosage on adsorption property of samples was studied. LDH samples modified by starch with starch versus Al3+ mole ratio of 0.0625 and calcinated at 450 °C for 5 h, exhibited higher crystallinity, higher surface area and more mesopores, which were beneficial to the adsorption process, the adsorption capacity on methyl orange (MO) reached 1555 mg/g. The kinetic data of adsorption were well fitted by the pseudo-second-order kinetic equation, while the isotherm data were well represented by the Langmuir equation. Starch doped method was a valid means to enhance adsorption performance.

Dielectric barrier discharge (DBD) non-thermal plasma was applied for ZnMgAl-LDHs modification to improve the adsorption property of methyl orange (MO). ZnMgAl-LDHs were prepared by co-precipitation method, and characterized via XRD, EDS, BET, SEM and FT-IR. Effects of plasma modification time, initial pH, initial MO concentration and adsorbent dosage on adsorption property of samples were investigated. The results showed that plasma modification led to the increase of specific surface area, pore volume and average pore size, as well as good dispersion. ZnMgAl-LDHs treated by combination of plasma modification for 30 min with calcination at 450 °C for 5 h exhibited high adsorption capacity of 1327 mg/g, much higher than without plasma modification. The equilibrium data for the adsorption of MO on adsorbents could be well fitted by the Pseudo-second-order equation and Langmuir equation. Plasma modification could be a potential and effective way for adsorption property improvement.

Vigorously developing new high performance liquid chromatography (HPLC) stationary phases to meet the versatile separation requirements is still an important issue in the field of analytical chemistry. Conjugated microporous polymers (CMPs) are a new type of three-dimensional network porous material with high specific surface area, good chemical stability and superhydrophobicity. Herein, we firstly report the synthesis and applications of CMPs@SiO2 material for HPLC stationary phase. The CMPs@SiO2 material can be in situ fabricated via Sonogashira coupling of 1,3,5-triethynylbenzene and 1,4-diiodobenzene on the surface of spherical silica. The morphology and physicochemical properties of the synthesized stationary phase material were investigated by a series of characterization methods. Due to the superhydrophobic nature of the CMPs@SiO2 material, the packed CMPs@SiO2 HPLC column displays ultrastrong chromatographic retention and can be used for separation of both hydrophobic and hydrophilic compounds with good selectivity. Significantly, CMPs@SiO2 column can be performed for separation with pure acetonitrile as the eluent. Thus, the new column was successfully exploited for monitor and analysis of the hydrolysis of silane coupling agents. Furthermore, based on its oleophilicity, this report firstly utilized the CMPs@SiO2 material to identify and analyze the quality of cooking oils through one-step enrichment and subsequent HPLC separation. We will further exploit to fabricate versatile CMPs-based stationary phases, highlighting their potential applications in different separation scopes.

Large quantity of fine Ti(C,N) particles, 15–30 nm in size, were observed in low carbon hot strips added to a small amount of Ti and produced by CSP process. The results showed that the precipitation of Ti(C,N) mostly took place during soaking and hot rolling, which is significantly different from that in the conventional production. These fine Ti carbonitride panicles could be very effective or. the austenite grain refinement by hindering grain growth of recrystallized austenite. Their precipitation behavior was discussed and compared with that of the steels produced in the conventional production.

International standard ISO-25498 specifies the method of selected area electron diffraction (SAED) analysis in TEM. It is applicable to the acquisition of SAED patterns, indexing the patterns and calibration of diffraction constant. Several features of this standard are introduced. As an example of the applications, phosphide with nanometer scale in a low-carbon steel produced by compact strip production process was analyzed by SAED and EDX. The phosphide precipitates in the steel are identified as MxP, where x is 2–3 and M is Fe, Ti, Cr, or Ni. It possesses a hexagonal lattice with lattice parameter a = 0.609 nm and c = 0.351 nm.

In this study, microstructures of 1.9 mm hot strip steel produced by compact strip production (CSP) are investigated by using optical metallograph observation and electron back-scattered diffraction (EBSD) data to deduce the status of hot rolled austenite before phase transformation, because the evolution of hot rolled austenite is important to provide information for the microstructure refinement. The experimental results show that the finishing hot rolled microstructure is a mixture of recrystallized and deformed austenite, and the percentage of recrystallized austenite is greater than that of the deformed austenite. At last, microstructure evolution of austenite is modeled based on chemical compositions and techniques of producing 1.9 mm hot strip. The simulation results agree well with experimental data. Analysis shows that microstructure refinement, recrystallization and supercooling rate are the primary causes to fine microstructure.

Fractal growth of molybdena, iodine, and carbon during vapor-solid transformation was studied experimentally. Three types of self-similar fractal clusters were observed, respectively. These clusters included two different crystalline structures, that is, single crystal and amorphous solid. The microstructure of single crystals included whiskers, ribbonlike crystals, and dendrites. The whiskers or ribbonlike crystals stacked together easily, and formed a bifurcation aggregate such as a molybdena fractal cluster. Under certain conditions, some dendrites were distorted and became branches of a network fluster. such as an iodine quasifractal cluster. The branching amorphous clusters of carbon aggregated at the edge of a glass sample after being irradiated by an electron beam. It is revealed phenomenologically from the experimental results that microstructures of these fractal clusters depended strongly on their growth conditions.

The structures of martensites in a Cu–11.2 wt% Al–3 wt% Ni specimen, which was quenched from 1173 K, have been studied by high resolution electron microscopy (HREM) and diffraction techniques. Two kinds of martensites, i.e. β′1 and γ′1, coexisting adjacent to each other in the specimen were observed. The γ′1 matensite consists of microtwins with monoclinic structure. Three variants of the twin structure, i.e. {1 2 1}, {2 1 0} and {1 0 1} twins, are arranged within a single plate. The β′1 martensite possesses basically ordered N9R structure, but mixed with thin 2H domains. Some diffraction spots of this martensite shift along the [0 0 1] direction. In addition, extra weak reflections appear in the diffraction pattern due to heterogeneous atomic displacements. The microstructural features of the martensites are examined and discussed.

Precipitates in two X80 pipeline steels were studied by transmission electron microscopy equipped with an energy filtering system. The steels are microalloyed with niobium and niobium–vanadium (Nb–V), respectively, and produced by continuous hot rolling. Besides the precipitates TiN and (Ti, Nb) (C, N), which were 10–100 nm in size, a large number of precipitates smaller than 10 nm distributed in the two steels have been observed. In the Nb–V microalloyed steel, only a few titanium nitrides covered by vanadium compounds on the surface have been observed. It is inferred that the vanadium exists mainly in the matrix as a solid solution element. The fact has been accepted that there was no contribution to the precipitation strengthening of the X80 steel by adding 0.04–0.06% vanadium under the present production process. By contrast, the toughness of the Nb–V steel is deteriorated. Therefore, a better toughness property of the Nb microalloyed X80 results from the optimum microalloying composition design and the suitable accelerating cooling after hot rolling.

Molybdena fractal clusters of various shapes were obtained experimentally in an evaporation-deposition system. The open ramified deposits grew after heating MoO3 powder at 750–900 °C for 0.5–2 h. They demonstrate two structural forms: the stack-like formation and the net-like one. Scanning electron microscopy observations revealed that the clusters consist of one of three different microstructures: needle-like whiskers, ribbon-like crystals, and fascicular crystals. Each pattern displays the microscopical anisotropy although they are of macroscopical self-similar feature. A nucleation-aggregation model is suggested to explain the non-equilibrium growth processes.

In this chapter, the microstructure and properties of low carbon steel produced by TSCR (Thin Slab Casting and Rolling) technology are studied, and compared with that of traditional process. The microstructure refinement and austenite recrystallization of low carbon steel produced by TSCR technology are presented. The characteristic and the mechanism of A1N precipitation in the steel are discussed based experimental results. The dynamics and corresponding model of precipitation during the heating and rolling are discussed also. The influences of A1N particles on the precipitation action in austenite region and on the ferrite transformation are analyzed. In addition, the softening mechanisms of low carbon steel for cold rolling by TSCR are explained. These include the property requirements of cold-rolled drawing sheets to hot strip, softening methods, grain coursing and softening mechanisms of B added low-carbon steel, the effects of the hot rolling and cooling technology on the softening of low carbon steel as well as the influences of different softening technology on the formability of cold-rolled 08A1 steels. On the other hand, the sulfide and oxide dispersive precipitates, other nanometer precipitates in the CSP low carbon steels, the carbides and carbonitrides in Ti containing steels, are introduced also in this chapter.

Much attention has been devoted to develop the new generation of microalloyed steels in recent years to meet the needs of high performance and low cost for the 21st century. The new type of steels is characterized by reduced carbon content, improved cleanness and refined grain size through the phase transformations.11'21 Precipitation of the carbonitrides in the steels is also one of the keypoints for controlling mechanical properties of the steels.In the present work ultra-low carbon clean microalloyed steels, which contain 0.029∽0.047(wt)%C, 1.48∽1.54(wt)% Mn, 0.044∽0.052(wt)%Nb, 0.025∽0.044Ti(wt)%, 0.0015∽0.0020(wt)%B and 0.0045∽0.0070(wt)%N, were prepared in a vacuum induction furnace in laboratory. The contents of S and P of the steels are 0.0005(wt)% and 0.0010∽0.0024(wt)% respectively. Total amount of the impurity elements O, S, P and H in the steels is 0.0061∽0.0077%. Dominant component of the structure in both casting and as-forged samples is acicular ferrite or bainite.

Structure of bainite in Cu-Al and Cu-Zn-Al alloys has been reported as 3R, 9R or 18R long period stacking structure (LPS) by X-ray and electron diffraction studies. In the present work, a Cu-25.5 (at)% Al alloy sample was heated at 900°C for 2 h then isothermally held at 450°C for 60 s before quenching into iced brine. FIG.1 shows a TEM bright field image of bainite plates (marked B) grown from grain boundary. The parent phase ( with DO3 structure ) has transformed to martensite (marked M ) during cooling from 450° C to 0°C. Both bainite and martensite plates have dense striations inside.Careful diffraction study on a JEOL 2000FX TEM with accelerating voltage 200 KV revealed (FIG.2) that the diffraction patterns contai_ning the same zone axis [001] ( hexagonal index ) or [111]c ( cubic index ) are from a bainite plate with obtuse V-shape. They are indexed as [010], [140], [130], [120], [230], [340] and [110] zone pattern for hexagonal system respectively.