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BiOBr sheets of controllable shape and size were synthesized via an ultrasound-assisted co-precipitation method at room temperature by varying the bromine source and reactant concentration. The BiOBr sheets synthesized from KBr and NaBr were rounded rectangles and round, respectively. The size of BiOBr sheets increased with increasing reactant concentration. As the reactant concentration increased from 10 mmol L−1 to 15 mmol L−1 until 20 mmol L−1, the size of as-prepared BiOBr sheets increased from 100–300 nm to 300–500 nm until 700–1000 nm, respectively. Moreover, the size difference in BiOBr sheets did not significantly affect the photocatalytic performance in degrading organic dyes. Such a simple and rapid method of controlling the shape and size of BiOBr sheets could provide more abundant matrix materials for the synthesis and modification of BiOBr.

Two new eight-layer hexagonal perovskites with the composition Ba8MNb6O24 (M = Fe and Cu) are synthesized by solid-state reaction at 1350-1400 °C. Their crystal structures have been investigated using X-ray and electron diffractions as well as high-resolution transmission electron microscopy. Although both compounds have similar M2+ size, Ba8FeNb6O24 and Ba8CuNb6O24 adopt shifted and twinned structures, respectively. Through comparison with the reported shifted Ba8MNb6O24 (M = Mn, Co, and Zn) and twinned Ba8NiNb6O24 as well as inexistent Ba8Mg(Nb/Ta)6O24, we elucidate that the twin-shift competition of Ba8MNb6O24 family could be related with multiple chemical factors including tolerance factors, B-cationic size difference, entropy variation with B-cation and vacancy disorder, Jahn-Teller distortion, and FSO B-B d orbit interactions.

Colloidal chemistry techniques at elevated temperatures (250–300°C) have been used to synthesize big (up to 20 nm) quantum dots (QDs) based on indium antimonide (InSb). In respect to their optical and electrical characteristics, the obtained big QDs exhibit properties similar to those of QDs with usual dimensions (4–5 nm), except the spectral maximum of luminescence being shifted inadequately to the size difference. This circumstance, together with the QD shape as measured by transmission electron microscopy, can be indicative of a less perfect crystalline structure of obtained big QDs, probably resulting from insufficiently high temperature of synthesis.

Sn-MFI zeolite is one kind of remarkable emerging solid Lewis acid catalyst with high stability in recent years, due to its wide application in the environmental-friendly biomass conversion and catalytic oxidation processes. Herein, it is confirmed that the Sn species are highly dispersed in the matrix of zeolite, and the expansion of unit cell is attributed to the formation of crystalline Sn O Si bonds, owing to the size difference between Si and Sn atoms. Due to the charge difference, Sn-MFI zeolites possess much more Lewis acid sites than Silicalite-1 and SnO2/Silicalite-1, and the catalytic property is closely related to the amount of Lewis acid sites. Consequently, it is reasonable to infer that the Sn atoms are inserted into the framework of Sn-MFI zeolite, in tetrahedral coordination, which acts as the active sites in Lewis acid catalyzed reactions.

Inorganic nanomaterials are emerging as widely applicable and solving complex modern world problems. Herein, this chapter introduces the use of microorganisms, especially their enzymes, for the synthesis of eco-friendly and cost-effective NPs. The use of enzyme in the synthetic process lets researcher controls the size, shape, growth, and reaction rate of NPs. It also lowers the need for high temperatures and other special requirements such as the use of toxic solvents or reducing agents as well as prevents the produced NPs from aggregation. The microgenic synthesis functionalized the produced NPs with certain immunogenic material due to the large amount of enzymes involved in the process, thus making it biocompatible for medical applications. However, despite the exceptional features of biogenic nanoparticles, there is still room available for improvement, such as the development of a synthetic process that is free from all the down processes (filtration, size difference, etc.), searching for the broader application of green NPs, searching for enzymes or proteins that can synthesize nanoparticle in optimum capacity at room temperature, and of course synthesizing NPs that can be used for the development of sustainable green economy and environment as well as one that can heal the devastations of climate change.

The small ubiquitin-like modifier (SUMO) is an important post-translational modifier that regulates various cellular processes. Extensive investigations have been made to comprehend the enzymatic process and consequence of SUMOylation. In vitro SUMOylation assays are invaluable for understanding the fundamental mechanisms of SUMOylation. A majority of these assays monitor changes in the size of the substrate upon SUMO conjugation. Current methods typically detect the size difference through SDS-PAGE and western blots, which makes these methods cumbersome, error-prone, and time-consuming. Here, we describe a fluorescence-based assay for real-time detection of SUMOylation. In the method, a fluorophore-tagged substrate is used in the SUMOylation reaction. Upon SUMOylation, the size and correlation time (τc ) of the substrate increases, and so does its anisotropy. The rate of change in anisotropy with time reflects the efficiency of the SUMOylation machinery. The real-time SUMOylation assay protocol is elegant, time-saving, and less prone to errors. © 2020 Wiley Periodicals LLC. Basic Protocol: Fluorescent anisotropy-based in vitro SUMOylation assay.

The effects of hot-strip coiling temperature on Ti(C,N) precipitation, texture and hydrogen permeation behavior in DC06EK enamel steel were investigated by TEM, EBSD test and electrochemical hydrogen permeation experiment. It was found that the Ti(C,N) particles in hot-strip coarsened with increasing coiling temperature, whereas after cold-rolling and annealing, the size difference of Ti(C,N) particles was lessened. The hot-strip coiling temperature has a significant impact on the recrystallized texture in the subsequent cold-rolled and annealed sheet. Hot-strip using high temperature (700 °C) coiling leads to strong {111} recrystallized texture in annealed sheet, with peak intensity 9.2. On the contrary, in annealed sheets using hot-strip coiling at 650 °C, their {111} recrystallized textures were weaker, which was also reflected in their rm values. Even though the hydrogen diffusion coefficient is slightly lower (7.76×10-5 mm2/s) in annealed sheet using low temperature coiling (600 °C), appropriately higher coiling temperature is more suitable for DC06EK enamel steel combining both good drawability and fish-scale resistance.

In the present research, molecular dynamics simulation is applied to study the in- teractions between tungsten dusts and a beryllium plasma-facing material surface. Calculation results show that it is quite difficult for nanometer-size dust particles to damage the plasma-facing material surface, which is different from the micrometer-size ones. The reason may be the size difference between dust and crystal grains. The depth of dust penetration into plasma-facing ma- terials is closely related to the incident velocity, and the impacting angle also plays an important role. Dust and material surface damage is also investigated. Results show that both incident velocity and angle can significantly influence the damage.

Microalgae represent the most promising new source of biomass for the world's growing demands. However, the biomass productivity and quality is significantly decreased by the presence of bacteria or other invading microalgae species in the cultures. We therefore report a low-cost spiral-microchannel that can effectively separate and purify Tetraselmis suecica (lipid-rich microalgae) cultures from Phaeodactylum tricornutum (invasive diatom). Fluorescent polystyrene-microbeads of 6 μm and 10 μm diameters were first used as surrogate particles to optimize the microchannel design by mimicking the microalgae cell behaviour. Using the optimum flowrate, up to 95% of the P. tricornutum cells were separated from the culture without affecting the cell viability. This study shows, for the first time, the potential of inertial microfluidics to sort microalgae species with minimal size difference. Additionally, this approach can also be applied as a pre-sorting technique for water quality analysis. ispartof: BIORESOURCE TECHNOLOGY vol:252 pages:91-99 ispartof: location:England status: published

Antifouling and sensitive-separation are two challenges for modifying poly (vinylidene fluoride) membrane. For the first time, we have reported a temperature- and pH-sensitive membrane with improved antifouling property. The membrane was prepared by phase separation of blends of poly (vinylidene fluoride)/poly ( N -isopropylacrylamide- co -acrylic acid) microgels/DMF in water. The hydrophilic poly ( N -isopropylacrylamide- co -acrylic acid) microgels are largely distributed in membrane bulk. Increasing poly ( N -isopropylacrylamide- co -acrylic acid) microgels helps to produce more pores and improve surface hydrophilicity of the PVDF membrane. Importantly, the membrane can separate solutes with little size difference by changing the temperature or pH condition; meanwhile, it shows a good fouling resistance for bovine serum albumin in response to temperature or pH change.

We detail the operation mechanism and instrumental limitations for potentiometric-scanning ion conductance microscopy (P-SICM). P-SICM makes use of a dual-barrel probe, where probe position is controlled by the current measured in one barrel and the potential is measured in a second barrel. Here we determine the interaction of these two barrels and resultant effects in quantitation of signals. Effects due to the size difference in pipet tip opening are examined and compared to model calculations. These results provide a basis for quantitation and image interpretation for P-SICM.

Expressed protein ligation (EPL) is a valuable tool to study site-specific functionalities on proteins such as posttranslational modifications. The purification of such ligation products from EPL mixtures can be cumbersome due to a small size difference between the expressed protein portion and the desired ligated protein. Therefore, affinity tags are often required, which remain on the protein after purification. Herein, we present an efficient protocol to install a photocleavable biotin building block on synthetic C-terminal tau[390-441] and describe its use for purification of full-length semi-synthetic tau[1-441].

Aptamers are single-stranded, synthetic oligonucleotides that fold into 3-dimensional shapes capable of binding non-covalently with high affinity and specificity to a target molecule. They are generated via an in vitro process known as the Systematic Evolution of Ligands by EXponential enrichment, from which candidates are screened and characterized, and then used in various applications. These applications range from therapeutic uses to biosensors for target detection. Aptamers for small molecule targets such as toxins, antibiotics, molecular markers, drugs, and heavy metals will be the focus of this review. Their accurate detection is needed for the protection and wellbeing of humans and animals. However, the small molecular weights of these targets, including the drastic size difference between the target and the oligonucleotides, make it challenging to select, characterize, and apply aptamers for their detection. Thus, recent (since 2012) notable advances in small molecule aptamers, which have overcome some of these challenges, are presented here, while defining challenges that still exist are discussed.

Crystallographic study of the Lu 3 Al 5 O 12 :Sc system shows existence of a wide range of compositions involving substitutions by Sc for both six-fold octahedral and eight-fold dodecahedral sites of the lattice. In comparison to other rare-earth garnets, the total amount of Sc that can be tolerated by this matrix is however much lower. The limited solubility of Sc is associated with the small size difference between the constituent atoms, which approaches a critical value with increasing the Sc content. Preparation of clear single-phase solid solution crystals requires an accurate account of site occupation preferences.

Microfluidics-based circulating tumor cell (CTC) isolation is achieved by using gelatin-coated silica microbeads conjugated to CTC-specific antibodies. Bead-binding selectively enlarges target cell size, providing efficient high-purity capture. CTCs captured can be further released non-invasively. This stratagem enables high-performance CTC isolation for subsequent studies.

RESUMO A determinação do nível de ploidia é muito importante, principalmente em programas de melhoramento genético que envolvem poliploides, a fim de possibilitar a escolha adequada dos materiais vegetais com os quais se deseja trabalhar. A relação entre o conteúdo de DNA de acessos de bananeira e sua ploidia ainda permanece controversa na literatura; assim, o presente trabalho teve como objetivo avaliar o conteúdo de DNA de acessos de bananeira com diferentes níveis de ploidia. Foram avaliados sete acessos tetraploides, quatro triploides e quatro diploides. A determinação do conteúdo foi realizada pela técnica de citometria de fluxo. Foram trituradas entre 50-60 mg de folhas frescas, juntamente com o padrão interno (Pisum sativum) no tampão LB01, e, posteriormente, as amostras foram filtradas em gaze e filtro de 50 µm. Adicionaram-se 5 µL de RNase e 25 µL de iodeto de propídeo. Para cada amostra, foram analisados 10 mil núcleos, com três repetições. Os resultados obtidos para o conteúdo de DNA permitiram estimar o tamanho dos genomas A e B, sendo o primeiro cerca de 14% maior que o segundo. Os resultados apresentaram clara relação entre o conteúdo de DNA e o nível de ploidia dos materiais. O contéudo de DNA apresentou aumento médio de 30% nas cultivares diploides em relação às cultivares triploides avaliadas e de 25% nas cultivares triploides em relação às cultivares tetraploides. Apesar da diferença nos tamanhos dos genomas A e B, contribuições distintas desses dois genomas não foram diretamente relacionadas com alterações no conteúdo do DNA de cultivares tetraploides. ABSTRACT Ploidy determination is very important, especially in breeding programs, to allow the correct choice of plant material to work. The relation between DNA content and ploidy level still has some controversies in literature, so the present study had the aim of evaluate DNA content in banana accesses with different ploidy levels. Data were evaluated from six tetraploid, four triploids and four diploids accesses. 50-60 mg of leave material were crushed with material from internal standard (Pisum sativum) in LB01 buffer and then filtered through gauze and 50 µm filter. It was added 5 µL of RNase and 25 µL of propide iodate. For each sample 10 thousand nuclei were analyzed with three repetitions. The DNA content results allowed separating genome A and B. Genome A appeared to be 14% major than genome B. Results showed a clear relationship between DNA content and ploidy level. DNA content increased 30% on average from diploid to triploid cultivars and 25% from triploid cultivars to tetraploid cultivars. Despite the size difference between genome A and B it could not be found a direct relationship between the contribution of these two genomes and the size of DNA content in tetraploid cultivars.

A modular set of phosphite-oxazoline (P,N) ligands has been applied to the title reaction. Excellent ligands have been identified for a range of substrates, including previously challenging terminally disubstituted olefins, where we now have reached enantioselectivities of 99% for a range of substrates. The selectivity is best for minimally functionalized substrates with at least a moderate size difference between geminal groups. A DFT study has allowed identification of the preferred pathway. Computational prediction of enantioselectivities gave very good accuracy.

The partitioning of thermodynamic quantities of the reference electrolyte (Ph4AsPh4B) is discussed by comparing its standard free energies of transfer from water to organic solvents (ΔWSG°) with those for Ph4AsPh4B. From experiment in 14 different dipolar-aprotic organic solvents, it is found that an asymmetric partition with the ratio: ΔWSG° (Ph4As+)/ΔWSG° (Ph4B−)=1.08 ± 0.02 is better justified than the equal partition practised in the literature. This asymmetry is mainly ascribed to the size difference between the reference cation and anion. The electrostatic contribution (ΔWSG°A(el)), primarily from iondipole interaction, does not appear as a cause for the asymmetry.

The positions of heterochromatic bands, 45S and 5S rDNA regions were detected on the chromosomes in three cultivars of cucumber (Cucumis sativus L.). The post-heated DAPI bands, which revealed heterochromatic region, were observed on the both terminal and pericentromeric regions of most of the chromosomes in three cultivars. However, these band patterns were different between European and Eastern Asian cultivars. The major 45S rDNA sites were found around the centoromeric region of the chromosomes 1, 2 and 5, and the minor 45S rDNA sites were found around centoromeric region of the chromosomes 3 and 7. The positional variation of this region was not found among three cultivars, but size difference was observed in the chromosome 5. The 5S rDNA site was observed on the interstitial region of the chromosome 6 in all of the cultivars studied. These results indicated that the variation of chromosome structure among cucumber cultivars occurred in the heterochromoatic region and suggested that the genetic variation in cucumber cultivars would be revealed by strict analysis and comparison for the position and size of heterochromatic region.

Densities and viscosities for the system, water (W) + 1,2-dimethoxyethane (DME), have been determined for the entire range of composition at temperatures, ranging from 303.15 to 323.15 K. Density, viscosity, enthalpy, entropy and free energy of activation for viscous flow have been plotted against the mole fraction of DME. Excess molar volume, , excess viscosity, η E, and excess free energy of activation, ΔG ≠E, have also been plotted against the mole fraction of DME. Most of these properties have been fitted to appropriate polynomial equations. Results have been explained in terms of such factors as, size difference of component molecules, hydrophilic effect, hydrophobic hydration and dipole–dipole interaction.

This paper presents development of a parylene membrane microfilter device for single stage capture and electrolysis of circulating tumor cells (CTCs) in human blood, and the potential of this device to allow genomic analysis. The presence and number of CTCs in blood has recently been demonstrated to provide significant prognostic information for patients with metastatic breast cancer. While finding as few as five CTCs in about 7.5mL of blood (i.e., 10(10) blood cells in) is clinically significant, detection of CTCs is currently difficult and time consuming. CTC enrichment is performed by either gradient centrifugation of CTC based on their buoyant density or magnetic separation of epithelial CTC, both of which are laborious procedures with variable efficiency, and CTC identification is typically done by trained pathologists through visual observation of stained cytokeratin-positive epithelial CTC. These processes may take hours, if not days. Work presented here provides a micro-electro-mechanical system (MEMS)-based option to make this process simpler, faster, better and cheaper. We exploited the size difference between CTCs and human blood cells to achieve the CTC capture on filter with approximately 90% recovery within 10 min, which is superior to current approaches. Following capture, we facilitated polymerase chain reaction (PCR)-based genomic analysis by performing on-membrane electrolysis with embedded electrodes reaching each of the individual 16,000 filtering pores. The biggest advantage for this on-membrane in situ cell lysis is the high efficiency since cells are immobilized, allowing their direct contact with electrodes. As a proof-of-principle, we show beta actin gene PCR, the same technology can be easily extended to real time PCR for CTC-specific transcript to allow molecular identification of CTC and their further characterization.

International audience; In order to determine the energetic driving forces for surface segregation in AuPd alloys, we use a combined approach coupling ab initio calculations and an analysis via an effective Ising model. Previously, this approach has been used successfully in the framework of N-body interatomic potentials to study the surface segregation in both semi-infinite alloys and nanoparticles, allowing one to determine the relative contributions of the different elementary driving forces. Here, we go beyond the use of N-body interatomic potentials by using ab initio calculations to evaluate the segregation enthalpy and the effective pair interactions, the contribution due to the size difference between the constituants being still obtained by N-body interatomic potentials. We show that the decomposition of the segregation enthalpy into its different elementary contributions is still valid at this level of description. This allows us to analyze the segregation driving forces in the two infinite dilute limits of the Au–Pd system, for both (100) and (111) surfaces. Finally, between the two infinite dilute limits, we find that our results are consistent with existing experimental data.

Energy calculations have been carried out on high-symmetry cuboctahedral Ni–Al nanoalloy clusters, of varying composition, with the interatomic interactions modelled by the Gupta many-body potential. Relaxations of cuboctahedral fragments cut from the bulk lattice of Ni 3 Al, with 13–561 atoms, were undertaken, as were relaxations of high symmetry clusters with 55 and 147 atoms. The lowest energy isomers were found to be dominated by three factors: the tendency toward mixing due to the favourable energy of mixing, Δ mix E ; the size difference between nickel and aluminium; and the higher cohesive and surface energy of nickel compared to aluminium. The latter two factors favour Al-segregation to the surface. The most stable Ni:Al composition approaches 3:1 for larger clusters.

We report molecular dynamics simulations of the production of radiation cascades in pyrochlores. We consider the apparently similar systems Gd2Ti2O7, Gd2Zr2O7 and Gd2Pb2O7, the first two of which have been put forward as potential materials for high-level radioactive waste storage. The effects of changing the mass of the 'primary knock-on' atom are also examined and we investigate whether the change in behaviour from Ti to Zr to Pb is largely due to the mass or the size difference between the elements. Problems associated with analysing the cascades and the damage created are discussed. There are clear differences between the three compounds. The simulations see no direct amorphization but rather a transition to the fluorite structure which is more pronounced for the Zr and Pb compounds than the Ti system. Underlying chemical trends are examined.

Due to its importance in Si-based devices, carbon incorporation in a silicon matrix has become an object of intensive research. However, the size difference between carbon and silicon makes this incorporation difficult, and only small amounts of carbon (a few percent) can be introduced without giving rise to SiC precipitation. Experimental and theoretical studies combined together have led to important progress in the general understanding of surface–subsurface carbon incorporation in the clean and hydrogenated Si(0 0 1) reconstructed surfaces. These results emphasize the role of the surface reconstruction and the carbon–carbon interactions. However, the Si(0 0 1) surface often presents defects such as dimer vacancies or ad-dimers. By modifying the local stress, these defects can play an important role in carbon incorporation. We review the results of recent studies and discuss the role of different relevant parameters such as local stress, carbon–defect interactions, carbon concentration, position and orientation of the defects, defect–defect distance, defect concentration… Finally, we show how, acting on the surface defects, one might improve carbon penetration in Si(0 0 1) and allow a better control of the carbon position in the subsurface layers.

The electrical conductivity spectra of three mixed alkali glass systems 0.3[xLi2O · (1 − x)R2O] · 0.7B2O3 (with R = Na, K, Rb; x = 0.0, 0.2, 0.4, 0.6, 0.8, 1.0) have been studied. For the first time it is reported that the strength of the mixed alkali effect does not always increase with the size difference of the involved alkali ions. The experimental results have been successfully interpreted by the structural model proposed by Swenson and his coworkers in combination with the structural considerations.

We present an integrated glass capillary system on silicon for size-based sieving of distinct mixtures of proteins, short DNA, and long DNA fragments into sharp peaks. The minimum resolvable size difference achieved is noted as 3.45 kDa for 45-52.8 kDa proteins, 20 bp for 200-300 bp DNA strands, and 182 bp for 5.6-5.8 kbp DNA chains. This high-resolution sieving arises from vastly steep entropic barriers created at the onsets of extremely restrictive (resistive) capillary segments and their pivotal role in shifting the equilibrium entropic sieving to intense fields (1000 V/cm). DNA fragments of various sizes are shown fully resolved in less than 7 min at a steady voltage of 2000 V being directly applied across the length of a 2 cm long sieve featuring thousands of entropic barriers. The utility of higher field strengths and longer sieves is also demonstrated without triggering dielectric breakdown by time-division multiplexing up to 2000 V across the 1 cm long sieve segments. The self-enclosed 70 nm diameter capillaries were fabricated using coarse (1 μm) photolithography and standard semiconductor manufacturing techniques.

In this paper, near-wall electrophoretic motion of spherical particles in cylindrical capillaries was experimentally investigated. It is demonstrated that same-sized particles move faster in smaller capillaries. This observation verifies the theoretical prediction of the wall enhancing effect in our recent paper (C. Ye, X. Xuan, D. Li, Microfluid. Nanofluid. 1 (2005)). Our experiments show that this wall enhancing effect becomes more significant when the size difference between particle and capillary becomes smaller and when a dilute electrolyte solution (i.e., thicker electric double layer) is used.

Turbot Scophthalmus maximus, larvae were start-fed with formulated feeds containing marine phospholipids (MP) or soya phospholipids (SP). The experiment was performed with six experimental groups, four groups were given formulated feeds, one group was given live feed and one group was starved. Phospholipid (PL) contents of the formulated feeds were respectively 5% MP, 15% MP, 5% SP and 15% SP. Larvae were offered feed from day 3 post-hatch. There was no significant size difference on day 5 between the group fed 15% MP and the group given rotifers. Electron microscopical examination of enterocytes was performed on larval intestine on day 5. Larvae fed 5% and 15% MP and larvae fed rotifers had normal looking enterocytes with numerous normal looking mitochondria. In the enterocytes of larvae fed 5% SP and 15% SP the mitochondria appeared swollen with a translucent matrix and fragmented cristae. Thus, MP and not SP seemed suitable as a lipid and PL source for start-feeding turbot larvae.

1. The authors' goal was to compare the size and density of Purkinje cells in the cerebellum of subjects with and without autism. Blocks of cerebellum were dissected at autopsy from the brains of age, sex- and postmortem-intervaled (PMI) groups of autistic and normal control individuals (N = 5 per group). Frozen, unfixed blocks were sectioned and stained with 1% cresyl violet. 2. The linear, molecular, granular densities and cross-sectional area of Purkinje cells were measured using computer-assisted image analysis. The average cross-sectional areas of Purkinje cells of the patients with autism were smaller by 24% when compared to the normal subjects. Two of the five autistic subjects had mean Purkinje cell sizes that corresponded to greater than 50% reduction in size. There was a substantial effect size difference in Purkinje cell size (eta2 = 0.29) between control and autistic brains (F(1, 8) = 3.32, P = 0.106). No differences in Purkinje cell densities were observed between the two groups 3. These data indicate the possibility of Purkinje cell atrophy in autism with significant neurohistological heterogeneity among individuals diagnosed with this disorder.

A novel enantioselective desymmetrization of 2,2-disubstituted 1,3-propanediols has been established to generate all-carbon quaternary stereocenters, which has been implemented with BzCl and Et3N in the presence of Pybox(6)-CuCl2 complex in CH2Cl2 or PhMe at −78°C. While all the cyanide-comprising diols were desymmetrized with superb enantioselectivity (higher than 98% ee), the stereoinduction of the other substrates greatly depends on the size difference between the two substituents at the 2-position. When the size difference becomes larger, the corresponding substrates tend to engender enhanced enantioselectivity (up to 99% ee).

The semiempirical theories of mixtures developed by van Laar, Margules, Scatchard-Hamer, Wilson and Renon and Prausnitz are used to study the concentration fluctuations of binary liquid alloys formed among the alkali metals. Examination of the fitting capabilities of these theories leads to the conclusion that those of van Laar, Scatchard-Hamer and Renon and Prausnitz are appropriate both when the atomic sizes of the component metals are similar and when there is considerable atomic size mismatch. The Margules and Wilson theories, on the contrary, appear to be restricted only to cases in which the size difference between the two types of atoms is small This work was supported in part by a Grant from the Spanish Comisiön Asesora de Investigaciön Cientifica y Tecnica SI

Bacterial separation from human blood samples can help with the identification of pathogenic bacteria for sepsis diagnosis. In this work, we report an acoustofluidic device for label-free bacterial separation from human blood samples. In particular, we exploit the acoustic radiation force generated from a tilted-angle standing surface acoustic wave (taSSAW) field to separate Escherichia coli from human blood cells based on their size difference. Flow cytometry analysis of the E. coli separated from red blood cells shows a purity of more than 96%. Moreover, the label-free electrochemical detection of the separated E. coli displays reduced non-specific signals due to the removal of blood cells. Our acoustofluidic bacterial separation platform has advantages such as label-free separation, high biocompatibility, flexibility, low cost, miniaturization, automation, and ease of in-line integration. The platform can be incorporated with an on-chip sensor to realize a point-of-care sepsis diagnostic device.

Synthetic (SiGe)-pyroxenoids are often observed to have superperiods. Whether or not these superperiods grow in connection with Si-Ge ordering is a fundamental question. The size difference between Ge and Si tetrahedra leads to CdGeO3 having the pyroxmangite structure, whereas CdSiO3 has the wollastonite structure. Consequently, considerable strain is expected for a pyroxenoid with a disordered Ge-Si distribution. A 29Si MAS-NMR study of a Cd-pyroxmangite of nominal composition Cd7[Ge6Si]O7 points to considerable Si clustering, probably as GeSiSiSiGe triples corresponding to the wollastonite-like units of the siebener chain. It is proposed that such ordering relieves strain within the tetrahedral chain. Residual strain is also relieved by insertion of an extra pair of GeO4 tetrahedra into the pyroxene-like component of the siebener-chain units, leading to single neuner-chain units which terminate the superperiods. This growth pattern is cyclic. The presence of several types of superperiod may reflect similar energetics for different Ge-Si-ordering patterns within the siebener chains. Ordering of Si-rich unit cells and of unit cells having no Si is proposed as the reason for the occurrence of the superperiods in Cd-pyroxmangite.

Sintering of two cylindrical particles of different sizes by surface diffusion at the early stage is theoretically analysed. Formulae for the neck growth rate are derived using a variational principle and the continuity equation of vacancies. The size difference between two particles is found to influence the growth rate of the neck only when the difference is large., 論文

We propose a simple physical model of phase separation of colloidal suspensions and emulsions, which we call the ``viscoelastic model.'' On the basis of this model, we consider two poorly understood phenomena: (i) phase separation accompanying the formation of a transient gel, and its collapse, and (ii) shear effects on composition fluctuations and phase separation. These phenomena can be explained by ``asymmetric stress division'' between the components of a mixture due to their size difference; the interaction network of particles can store elastic energy, while a fluid component cannot. The importance of the bulk stress stemming from an interaction network is discussed, using a concept of self-induced elastic constraint due to connectivity. We argue that there are common features to polymer solutions, colloidal suspensions, emulsions, and possibly protein solutions. They originate from dynamic asymmetry between the components and the resulting interaction network of the slower component of a mixture, which leads to the formation of a transient gel.

Inner ear stones (otoliths) of developing cichlid fish ( Oreochromis mossambicus ) were marked with the calcium tracer alizarin-complexone (AC) at 1g-earth gravity before and after a long-term (20 days) stay of the animals at moderate hypergravity conditions (3g; centrifuge). AC deposition at the otoliths resulted in two fluorescence bands, which enclosed the area grown during exposure to altered gravity. This area was measured with regard to size and asymmetry (size difference between the left and the right stones). Both utricular and saccular otoliths (lapilli and sagittae, respectively) were significantly smaller after hyper-g exposure as compared to parallely raised 1g-control specimens. The asymmetry concerning the lapilli was pronouncedly decreased in comparison to the 1g-controls. These findings suggest, that the growth and the development of bilateral asymmetry of otoliths is guided by the environmental gravity vector. Some of the hyper-g animals revealed a kinetotic behaviour at the transfer from hyper-g to normal 1g-earth gravity conditions, which was qualitatively similar to the behaviour observed in previous experiments at the transfer from 1g to microgravity in the course of parabolic aircraft flights. The lapillar asymmetry of kinetotic samples was found to be significantly higher than that of normally behaving experimental specimens. This result supports an earlier theoretical concept, according to which human static space sickness might be based on asymmetric utricular otoliths.

The microscopic surface structure of InP(001) is investigated by combining first-principles total-energy calculations with soft-x-ray photoelectron spectroscopy and scanning tunneling microscopy. The 4\ifmmode\times\else\texttimes\fi{}2 cation dimer model adapted from Ga-rich GaAs(001) surfaces as well as recently proposed, rather complex 2\ifmmode\times\else\texttimes\fi{}4 trimer reconstruction models are found to be unstable. The energetically favored 2\ifmmode\times\else\texttimes\fi{}4 reconstructions are stabilized by dimerized In and P atoms. Unlike the well-known GaAs surface, however, mixed In-P dimers are preferred for cation-rich surfaces due to the notable size difference between the material constituents.

The segregation phenomena of different binary mixtures were studied experimentally in a vertical shaker. The larger particles tend to move upwards in the shaker in a certain range of vibrational accelerations. The segregation effect was more significant for the mixture with a larger size difference. The segregation coefficient was measured and found to increase with vibrational acceleration until reaching a maximum and then to decrease with acceleration. The bed expansion height was also measured. It was found that the greatest segregation effect occurred when the bed transformed from a dense state to a loose state.

The most important factors affecting the Snoek peak height of carbon in commercial steel sheets are shortly reviewed. It is shown that the proportionality factor K Q + (=Q max -1 /C i )-for a given interstitial and a given internal damping technique-mainly is affected by the steel texture and the presence of substitutional atoms. The influence of texture and composition is illustrated for four non oriented electrical steels with Si-contents between 0 and 1.8%. This difference in Si-content, combined with differences in C-content between the internal damping specimens, resulted in significant texture changes, providing an interesting frame not only to apply the theory on the orientation dependence of the calculated proportionality factor K Q (developed in a previous paper), but also to discuss the effect of alloying elements on the Snoek peak height. The proportionality factors of the experimentally measured textures are calculated by making the convolution product of the orientation distribution function (ODF) of the measured texture and the distribution function of K Q . Doing so, the effect of texture on the experimentally measured K Q + can be separated from the direct effect of the substitutional elements (mainly Mn, Al and Si). The latter effect is discussed in terms of the elastic strain present around substitutional atoms due to their size difference with Fe atoms.

We study the efficacy of bone regeneration by using two differently sized allogeneic cancellous bone granules loaded with autologous cultured osteoblasts in a rabbit model. Critical-sized bone defects of the radial shaft were made in 40 New Zealand White rabbits. Small allogeneic bone granules (150–300 μm in diameter) loaded with cultured differentiated autologous osteoblasts were implanted into one forearm (SBG group) and large bone granules (500–710 μm) loaded with osteoblasts were implanted into the forearm of the other side (LBG group). Radiographic evaluations were performed at 3, 6, 9 and 12 weeks and histology and micro-CT image analysis were carried out at 6 and 12 weeks post-implantation. On radiographic evaluation, the LBG group showed a higher bone quantity index at 3 and 6 weeks post-implantation (P

The stereochemical course of reductions of iminium ions with sodium cyanoborohydride and sodium triacetoxyborohydride was examined within the context of model studies directed toward the synthesis of the quinolizidine alkaloid clavepictine A. Conformational preferences of the iminium ion and and effective size of the reducing agent were shown play a role in determining reduction stereochemistry.

We study the nature of intermediate range order (IRO) in a 2:1 model liquid binary mixture as the range of the potentials is changed from short to long range. The calculations were carried out within the Mean Spherical Approximation, and the study focuses on the Bhatia-Thornton partial structure factors. We find evidence of IRO when there is size difference between the atoms in the mixture. However, at the level of description of this work, there appears no way of distinguishing between the IRO in a compound forming or an ionic system.

A theoretical model based on the grand partition function has been developed to investigate the role of size effects on surface tension and surface segregation of liquid binary alloys. The necessary relation, which connects the surface composition with surface tension through order potential, surface coordination and volume ratio, is obtained. This has been applied to liquid Na-Cs alloys. Likewise bulk properties, surface segregation and surface tension of Na-Cs liquid alloys are also affected appreciably by the size difference and are anomalous around C Na = 0.8.

Intracellular crowding in biological systems is usually mimicked in in vitro experiments by adding single crowders at high volume fractions, without taking into consideration the polydispersity of the crowders in the cellular environment. Here, we develop a molecular thermodynamic formalism to examine the effects of size-polydispersity of crowders on aggregation reaction equilibria. Although the predominantly common practice so far has been to appeal to the entropic (excluded-volume) effects in describing crowding effects, we show that the internal energy (hence, the enthalpy) of the system could dramatically alter the effects, even qualitatively, particularly in the case of a mixture of crowders, depending on the changes in the covolume of the products relative to that of the reactants and on the preferential binding or exclusion of the crowders by the reactants and products. We also show that in the case of polydisperse crowders the crowders with the largest size difference dominate the overall changes in the yield of the reaction, depending on the individual concentrations of the crowders.

We examine the effects of atomic mobility on solid state amorphization reactions by comparing reactions in Ni/ZrxTil-x composites as the Zr concentration, x , is varied. X-ray diffraction and differential scanning calorimetry are utilized to study the growth of amorphous phases. Differences in solid state reactions in these systems can be attributed to the size difference in the Zr and Ti atoms, and resulting variations in atomic mobilities. At low temperatures (300 K e T c 650 K) in the Ni-ZrxTil-x system we observe a direct dependence of the rate of solid state reaction on Zr concentration.

The stereochemical course of reductions of iminium ions with sodium cyanoborohydride and sodium triacetoxyborohydride was examined within the context of model studies directed toward the synthesis of the quinolizidine alkaloid clavepictine A. Conformational preferences of the iminium ion and and effective size of the reducing agent were shown play a role in determining reduction stereochemistry.

First, a survey is given of semiempirical approaches designed for predicting physical and chemical properties of binary alloy systems from the properties of the elements. The same goal is pursued with the help of a pseudopotential theory with optimum transferability derived from relativistic quantum mechanics. The curves of the l-dependent bare-ion pseudopotentials are computed, the spin—orbit coupling being taken into account, and a characteristic radius and a characteristic energy are determined for each of these curves. These dual coordinates are used for the preparation of structure maps in order to predict for binary (1:1) alloys and compounds with a fair degree of probability: space group and structure type of the crystals under normal temperature and pressure conditions, lattice constants, melting temperature, etc. A particularly successful approach is to compute from the dual coordinates a kind of size difference and a function of the hybridization, which then in turn are used as new dual coordinates. Zuerst wird ein Uberblick uber die semiempirischen Verfahren gegeben, die fur die Vorhersage der physikalischen und chemischen Eigenschaften binarer Legierungen aus den Eigenschaften der Elemente entwickelt wurden. Dasselbe Ziel soll mit Hilfe einer Pseudopotentialtheorie mit optimaler Ubertragbarkeit, die aus der relativistischen Quantenmechanik abgeleitet wurde, erreicht werden. Die Verlaufe der l-abhangigen Ionenpseudopotentiale werden unter Berucksichtigung der Spin—Bahn-Kopplung berechnet und ein charakteristischer Radius sowie eine charakteristische Energie fur jede dieser Kurven bestimmt. Diese dualen Koordinaten werden fur die Erstellung einer Strukturkarte benutzt, um mit betrachtlicher Wahrscheinlichkeit fur binare (1 : 1)-Legierungen und -verbindungen die Raumgruppe und den Strukturtype der Kristalle unter normalen Temperatur- und Druckbedingungen, die Gitterkonstanten, Schmelztemperaturen usw. vorherzusagen. Besonders erfolgreich ist es, aus den dualen Koordinaten eine Art Grosendifferenz und eine Funktion der Hybridisierung zu berechnen, die dann als neue duale Koordinaten benutzt werden konnen.

Dipeptide sweeteners of the AspNHCH(R1)COR type, where R1 = H, Me, CH2OH, and CO2Me and R = OR2 or NHR2 with R2 less-than-or-equal-to C10 atoms, i.e., alkyl, aryl, heterocyclic, bi- or tricyclic group, were synthesized to remedy the well-known shortcomings of aspartame. For the design of these sweeteners, the classic theory of Cohn-Oertly-Myers, Ariyoshi's rule of steric size difference, Newman's rule of H-6 number as well as our C-9 rule and a model of induced fitting of multiple-point attachment with the sweet receptor were employed. On the basis of our results as well as those of others, qualitative and semi-quantitative structure-activity relationships were discussed according to the current concepts of polar-steric-hydrophobic factor analyses for the pursuit of an ideal high sweetness potency dipeptide sweetener. Compounds of high sweetness potency prepared in this work are all of high stabilities and indifferent to microorganisms or any known genetic diseases.