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In this work, we unravel the role of surface properties of colloidal particles on the formation of supraparticles (clusters of colloidal particles) in a colloidal Ouzo droplet. Self-lubricating colloidal Ouzo droplets are an efficient and simple approach to form supraparticles, overcoming the challenge of the coffee stain effect in situ. Supraparticles are an efficient route to high-performance materials in various fields, from catalysis to carriers for therapeutics. Yet, the role of the surface of colloidal particles in the formation of supraparticles using Ouzo droplets remains unknown. Therefore, we used silica particles as a model system and compared sterically stabilized versus electrostatically stabilized silica particles - positively and negatively charged. Additionally, we studied the effect of hydration. Hydrated negatively charged silica particles and sterically stabilized silica particles form supraparticles. Conversely, dehydrated negatively charged silica particles and positively charged amine-coated particles form flat film-like deposits. Notably, the assembly process is different for all the four types of particles. The surface modifications alter (a) the contact line motion of the Ouzo droplet and (b) the particle-oil and particle-substrate interactions. These alterations modify the particle accumulation at the various interfaces, which ultimately determines the shape of the final deposit. Thus, by modulating the surface properties of the colloidal particles, we can tune the shape of the final deposit, from a spheroidal supraparticle to a flat deposit. In the future, this approach can be used to tailor the supraparticles for applications such as optics and catalysis, where the shape affects the functionality., 38 pages, 9 figures

Preconcentration of the target compound is a critical step that ensures the accuracy of the subsequent chemical analysis. In this work, we present a straightforward yet effective liquid-liquid extraction approach based on surface nanodroplets (i.e., nanoextraction) for offline analysis of highly diluted sample solutions. The extraction and sample collection were streamlined in a 3-m microcapillary tube. The concentration of the target analyte in surface nanodroplets was significantly increased compared to the concentration in the sample solution, reaching several orders of magnitudes. A limit of detection (LOD) was decreased by a factor of $\sim 10^3$ for an organic model compound in Fourier-transform infrared spectroscopy (FTIR) measurements and $\sim 10^5$ for a model fluorescent dye in fluorescence detection. The quantitative analysis of the organic compound was also achieved in a wide concentration region from $10^{-3}$ M to $10^{-4}$ M. The total volume of surface nanodroplets can be manipulated to further enhance extraction efficiency, according to the principle that governs droplet formation by solvent exchange. Additionally, our method exhibited significantly improved sensitivity compared to traditional dispersive liquid-liquid microextraction (DLLME). The LOD of the fluorescent dye and the organic model compound obtained with DLLME was 3 orders of magnitude and 20 times higher than the LOD achieved through nanoextraction approach. The nanoextraction developed in this work can be applied to preconcentrate multi-compounds from river water samples, without clear interference from each other. This can further extend its applicability for the detection and quantification of target analytes in complex aqueous samples by common analytical instruments.

Traditional Sol-Gel KNN film prepared either with niobium ethoxide C10H25NbO5 (metal alkoxide route) or niobium oxide Nb2O5 (non-alkoxide route) as niobium source. However, they are either extremely expensive or of poor quality for films. Hence, a novel and manageable Sol-Gel process based on the combination of the above two routes was developed to achieve high-quality KNN films. Here, highly (h00)-oriented KNN homo-multilayer films were fabricated on traditional Si by an alternating non-alkoxide and metal alkoxide route. As expected, these KNN films have much higher oriented degree than that prepared by any single route. Benefited from the flexibility of alternating sol-gel synthesis routes and homo-multilayered film design, the crystal structures and electrical properties of KNN films can be tailored effectively by the period number N and annealing temperature. The results suggest that the employing of homo-interfaces may be an effective method to improve the crystallinity and performances of sol-gel films.

In this study, ITO and Pt layers were deposited on (100) Si substrate respectively as bottom electrode for ZnO-based resistive memory. The ITO layer was textured and its preferred orientation is highly dependent on the oxygen partial pressure of growth atmosphere. As the oxygen content increases in the range of 0%–15%, the preferential growth orientation tends to change from (400) to (222). (002)-textured ZnO thin films with different preferred orientation degree sputtered on Pt and two kinds of oriented ITO layers were comparatively investigated. The device with (400)-ITO bottom electrode was found to have the best resistive switching performance. Meanwhile, the differences in switching behaviors were also found to be closely related to the thickness-dependent crystalline structure and top contact electrode/interface. This study provides an in-depth understanding of the structural design and structure-activity relationship of high-performance ZnO-based resistive memory.

The transport and aggregation of particles in suspensions is an important process in many physicochemical and industrial processes. In this work, we study the transport of particles in an evaporating binary droplet. Surprisingly, the accumulation of particles occurs not only at the contact line (due to the coffee-stain effect) or at the solid substrate (due to sedimentation) but also at a particular radial position near the liquid-air interface, forming a "ring", which we term as the Marangoni ring. The formation of this ring is primarily attributed to the solutal Marangoni flow triggered by the evaporation dynamics of the water-glycerol droplet. Experiments and simulations show fair agreement in the volume evolution and the general structure of the solutal Marangoni flow, that is, the Marangoni vortex. Experiments show that the location of the Marangoni ring is strongly correlated with the Marangoni vortex. However, finite element numerical simulations fail to describe the particle distribution seen in the experiments. Interestingly, the particles not only accumulate to form the Marangoni ring but also assemble as colloidal crystals dose to the liquid-air interface, yielding iridescence. The formation of the colloidal crystals in the experiments is strong evidence that non-hydrodynamic interactions, which are not represented in the simulations, also play a significant role in our system., Langmuir, 38 (39), ISSN:0743-7463, ISSN:1520-5827

This paper describes the fabrication of heteromorphic microlens arrays in the polymethyl methacrylate/titanium/organically modified siloxanes photosensitive hybrid films by UV nanoimprint technique and the applications of the prepared microlens arrays on the organic light-emitting diode. The hybrid films were obtained by combining a sol–gel technique and spin coating method. UV–visible spectroscopy and atomic force microscope are used to characterize the properties of the hybrid films, and the results indicate that the hybrid films have high transmittance and small surface roughness. Scanning electron microscope and surface profile results show that the heteromorphic microlens arrays formed in the hybrid films are uniform and well defined. Optical microscopy results show that the hexagonal microlens arrays have the relatively strong focusing ability and excellent imaging performance. Finally, the microlens arrays are applied to the organic light-emitting diode, the luminous properties of the organic light-emitting diode is enhanced, and there is a maximum improvement of about 43.9% in current efficiency for OLEDs with hexagonal microlens arrays. All the results above indicate that it is a simple and low-cost process to fabricate hybrid film microlens arrays by UV nanoimprint technique, and the prepared microlens arrays have potential applications in the organic light-emitting diode.

Fabricating of highly-oriented pure-phase potassium sodium niobate (KNN) films on traditional Si substrates by low-cost manageable sol-gel technique (especially with non-alcohol niobium salt Nb 2 O 5 as niobium source) is still a work of great challenge. Here, KNN films were prepared on Pt/Ti/SiO 2 /Si and LNO/Si substrates via a sol-gel non-alkoxide process. And a comprehensive set of experimental investigations to the role of the bottom electrode, annealing atmosphere and the number of coating layers on the microstructures and electrical properties involution of spin-coated KNN films were made. The crystal structures, preferential orientation and morphology of KNN films are strongly affected by the annealing atmosphere, as well as the bottom electrode material. KNN films annealed in air show an obviously better crystal structure and denser surface than that annealed in oxygen, and KNN film spin-coated on LNO bottom electrode and annealed in air exhibits a dominant ( h 00) orientation with a high preferred degree of 93.6%. In addition, it also can be found that the increasing number of coating layers of KNN films also results in better crystalline structures (higher oriented degree, larger grains, narrower FWHM) and electrical performance. KNN film with 18 layers shows the largest dielectric constant of 868 and the lowest loss tangent of 2.8%.

PS microspheres emulsions with different PS diameters of 207 and 378 nm were prepared by using an emulsifier-free polymerization method. A novel secondary self-assembly method which combined the spin coating and the lifting-up method was used to prepare the close-packed PS MCC films. During the process, the PS MCC film was firstly assembled on a glass substrate by a spin coating technique. Secondly, the obtained PS MCC film was transferred on the air-water interface by immersing the PS glass substrate in water using a dip-coater. Thirdly, the floating close-packed PS MCC films on the air-water interface was transferred to a new glass substrate by using a lifting-up method. During the spin-coating and the self-assembly process, some SDS solution was added in the PS films to improve the uniformity of the PS layer. Effects of the spin-coating speeds, the SDS solution concentration and the lifting-up rates on the morphology of PS MCC films have been discussed. Scanning electron microscopy was used to observe the morphological properties of the PS colloidal crystal films. Results indicate that a relatively close-packed and large scale PS MCC films can be obtained when the spinning speed is 2000 rpm for 60 s, the SDS solution concentration is 2 wt% and the lifting-up rate is 2 mm/min. Furthermore, the polydimethylsiloxane soft mold was replicated from the-fabricated PS MCC films and was then imprinted onto the photosensitive hybrid film under UV-irradiation and thus the micro-lens arrays built in the photosensitive hybrid sol–gel film were obtained.

In this work, we investigate crystallization from droplets formed on micro-patterned surfaces. By solvent exchange in a micro-chamber, a ternary solution consisting of a model compound beta-alanine, water, and isopropanol, was displaced by a flow of isopropanol. In the process, oiling-out droplets formed and crystallized. Our results showed that the shape and size of the crystals on micro-patterned surfaces could be simply mediated by the flow conditions of solvent exchange. Varying flow rate, concentration, or channel height led to the formation of a thin film with micro-holes, connected network of crystals, or small diamond-shaped crystals. Rough micro-structures on the surface allowed the easy detachment of crystals from the surface. Beyond oiling-out crystallization, we demonstrated that the crystal formation from another solute dissolved in the droplets could be triggered by solvent exchange. The length of crystal fibers after the solvent exchange process was shorter at a faster flow rate. This study may provide further understanding to effectively obtain crystallization from surface droplets through the solvent exchange approach., Comment: 23 pages, 11 figures

Compartmentalizing reagents within small droplets is promising for highly efficient conversion and simplified procedures in many biphasic chemical reactions. In this work, surface nanodroplets (i.e., less than 100 nm in their maximal height) were employed to quantitatively understand the size effect on the chemical reaction rate of droplets. In our systems, a surface-active reactant in pure or binary nanodroplets reacted with the reactant in the bulk flow. Meanwhile, the product was removed from the droplet surface. The shrinkage rate of the nanodroplets was characterized by analyzing the lateral size as a function of time, where the droplet size was solely determined by chemical reaction rate at a given flow condition for the transport of the reactant and the product. We found that the overall kinetics increases rapidly with the decrease of droplets lateral radius R, as dR/dt ~ R^(-2). The faster increase in the concentration of the product in smaller droplets contributes to accelerating reaction kinetics. The enhancement of reaction rates from small droplet sizes was further confirmed when a non-reactive compound presented inside the droplets without reducing the concentrations of the reactant and the product on the droplet surface. The results of our study improve the understanding of chemical kinetics with droplets. Our findings highlight the effectiveness of small droplets for the design and control of enhanced chemical reactions in a broad range of applications.

Neodymium oxide nanocrystals are synthesized by an inverse microemulsion method. XRD, XPS and HRTEM are used to characterize the properties of the neodymium oxide nanocrystals. Results show that the prepared neodymium oxide particles have obvious "column” structure with a column width of 400 ~ 600 nm and a length of 1 ~ 4 µm and have nanocrystalline structure with a high crystallinity. Neodymium-doped TiO2/organically modified silanes (ormosils) organic–inorganic composite films were prepared by using a sol–gel spin coating method. Up-conversion emission and optical transmittance of the films baked at different temperature were studied. Results indicate that the up-conversion emission occurs at about seven wavelength numbers of 387, 404, 421, 436, 450, 478 and 487 nm, of which the bright blue emission at 436 nm has the strongest intensity. There is a high optical transmittance value of above 88% for all the samples in the wavelength number 500 ~ 1000 nm. Optical waveguide properties including the optical transmission modes and loss of the composite films were measured. The photochemical properties of the composite films were also demonstrated by FTIR spectra. Besides, an energy level diagram was used to explain the mechanism of the up-conversion emission from neodymium oxide nanocrystals. Finally, strip waveguides with different waveguide sizes were built in the composite films through a UV soft nanoimprint technique and the surface morphology of the waveguides was observed by SEM. The as-prepared neodymium-doped composite films have potential applications in the areas of photonics and micro-optical devices.

Nanocolumn InGaN/GaN single quantum well crystals were deposited on Si (111) substrate with nitrified Ga dots as buffer layer. Transmission electron microscopy image shows the crystals' diameter of 100–130 nm and length of about 900 nm. Nanoscale spatial phase separation of cubic and hexagonal GaN was observed by selective area electron diffraction on the quantum well layer. Raman spectrum of the quantum well crystals proved that the crystals were fully relaxed. Room temperature photoluminescence from 450 to 750 nm and full width at half maximum of about 420 meV indicate broad color luminescence covering blue, green, yellow and red emission, which is helpful for the fabrication of tunable optoelectronic devices and colorful light emitting diodes.

The compartmentalization of chemical reactions within droplets has advantages in low costs, reduced consumption of reagents and increased throughput. Reactions in small droplets have also been shown to greatly accelerate the rate of many chemical reactions. The accelerated growth rate of nanobubbles from nanodroplet reactions is demonstrated in this work. The gaseous products from the reaction at the nanodroplet surface promoted nucleation of hydrogen nanobubbles within multiple organic liquid nanodroplets. The nanobubbles were confined within the droplets and selectively grew and collapsed at the droplet perimeter, as visualized by microscopy with high spatial and temporal resolutions. The growth rate of the bubbles was significantly accelerated within small droplets and scaled inversely with droplet radius. The acceleration was attributed to confinement from the droplet volume and effect from the surface area on the interfacial chemical reaction for gas production. The results of this study provide further understanding for applications in droplet enhanced production of nanobubbles and the on-demand liberation of hydrogen.

Surface nanobubbles are nanoscopic spherical-cap shaped gaseous domains on immersed substrates which are stable, even for days. After the stability of a {\it single} surface nanobubble has been theoretically explained, i.e. contact line pinning and gas oversaturation are required to stabilize them against diffusive dissolution [Lohse and Zhang, Phys.\ Rev.\ E 91, 031003 (R) (2015)], here we focus on the {\it collective} diffusive interaction of {\it multiple} nanobubbles. For that purpose we develop a finite difference scheme for the diffusion equation with the appropriate boundary conditions and with the immersed boundary method used to represent the growing or shrinking bubbles. After validation of the scheme against the exact results of Epstein and Plesset for a bulk bubble [J. Chem. Phys. 18, 1505 (1950)] and of Lohse and Zhang for a surface bubble, the framework of these simulations is used to describe the coarsening process of competitively growing nanobubbles. The coarsening process for such diffusively interacting nanobubbles slows down with advancing time and thus increasing bubble distance. The present results for surface nanobubbles are also applicable for immersed surface nanodroplets, for which better controlled experimental results of the coarsening process exist.

Droplet formation in oiling-out crystallization has important implication for separation and purification of pharmaceutical active ingredients by using an antisolvent. In this work, we report the crystallization processes of oiling-out droplets on surfaces during solvent exchange. Our model ternary solution is beta-alanine dissolved in isopropanol and water mixture. As the antisolvent isopropanol displaced the alanine solution pre-filled in a microchamber, liquid-liquid phase separation occurred at the mixing front. The alanine-rich subphase formed surface microdroplets that subsequently crystallized with progression of solvent exchange. We find that the flow rates have significant influence on the droplet size, crystallization process, and growth rate, and final morphology of the crystals. At fast flow rates the droplets solidified rapidly and formed spherical-cap structures resembling the shape of droplets, in contrast to crystal microdomains or thin films formed at slow flow rates. On a highly hydrophilic surface, the crystals formed thin film without droplets formed on the surface. We further demonstrated that by the solvent exchange crystals can be formed by using a stock solution with a very low concentration of the precursor, and the as-prepared crystals can be used as seeds to trigger crystallization in bulk solution. Our results suggest that the solvent exchange has the potential to be an effective approach for controlling oiling-out crystallization, which can be applied in wide areas, such as separation and purification of many food, medical, and therapeutic ingredients., Comment: Advanced Materials Interfaces (2020)

Flow transport in confined spaces is ubiquitous in technological processes, ranging from separation and purification of pharmaceutical ingredients by microporous membranes and drug delivery in biomedical treatment to chemical and biomass conversion in catalyst-packed reactors and carbon dioxide sequestration. In this work, we suggest a distinct pathway for enhanced liquid transport in a confined space via self-propelling microdroplets. These microdroplets can form spontaneously from localized liquid-liquid phase separation as a ternary mixture is diluted by a diffusing poor solvent. High speed images reveal how the microdroplets grow, break up and propel rapidly along the solid surface, with a maximal velocity up to ~160 um/s, in response to a sharp concentration gradient resulting from phase separation. The microdroplet self-propulsion induces a replenishing flow between the walls of the confined space towards the location of phase separation, which in turn drives the mixture out of equilibrium and leads to a repeating cascade of events. Our findings on the complex and rich phenomena of self-propelling droplets suggest an effective approach to enhanced flow motion of multicomponent liquid mixtures within confined spaces for time effective separation and smart transport processes., Comment: This is the authors' submitted version of the manuscript

T i O 2 -based organic–inorganic composite films doped with azobenzene and photosensitive groups were prepared by combining a low-temperature solgel technique and a spin-coating method. The influence of T i O 2 content on the optical and structural properties of the composite films including the film thickness, the refractive index, the transmission loss, the thermal gravity analysis, and Fourier transform infrared spectroscopy spectra was studied. Photoisomerization and optical switching characteristics of the composite film were investigated under the irradiation of 365 nm ultraviolet light and 450 nm visible light. Results indicate that several micrometer thick films can be easily obtained at room temperature and there is a proportional relationship between the refractive index value and the T i O 2 content. In addition, the composite films have a low optical propagation loss of about 0.1 dB/cm. The composite films with 0.2 M T i O 2 content have an obvious photoisomerization and good optical switching properties. Finally, the hexagonal microlens array was fabricated in the composite films by using an ultraviolet nanoimprint technology. All these results above indicate that the as-prepared T i O 2 -based organic–inorganic composite film has potential applications in optical switching devices and photonic elements.

The C Satellite of Environment and Disaster Monitoring and Forecasting Small Satellite Constellation (HJ-1-C) was launched successfully on 19 November 2012. It is the first Synthetic Aperture Radar (SAR) satellite for civil use in China and the only S-band SAR satellite on orbit in the world at present. One of its applications is to extract water body, which can be used for assessing the severity of floods or drought . As the user of the S Band SAR Satellite of HJ-1-C, the National Disaster Reduction Center of China (NDRCC) has the responsibility to assess its water body extraction capability and precision. This study validates the water extraction precision using the HJ-1-C by means of comparison with water body delineation using optical images of the HJ-1-B and ZY-3. The result shows that, the C Satellite has a prominent advantage in extracting details of water bodies as compared with the HJ-1-A and HJ-1-B.

Porcine parvovirus (PPV) is a major cause of the syndrome of sow reproductive failure that can cause economic losses. In this study, we developed a subunit vaccine against porcine parvovirus (PPV), composed of virus-like particles (VLPs) derived from a prokaryotic system, and evaluated its potential against PPV infection. The soluble recombinant VP2 protein was expressed in E. coli Transetta(DE3) cells using a pCold II prokaryotic expression vector at a low temperature of 15 °C. After expression and purification, the recombinant VP2 protein was successfully assembled into VLPs with a similar shape of PPV viron and also hemagglutination activity. PPV VLPs formulated in a water-in-oil-in-water adjuvant evoked high hemagglutination inhibition antibody and neutralization antibody titres in both guinea pigs, used as reference model, and target species, pigs. Immunization with VLPs vaccine stimulated high hemagglutination inhibition antibody and neutralization antibody responses in guinea pigs, used as reference, and target species, weaned pigs, and primiparous gilts. PPV VLPs from E. coli yielded complete fetal protection against PPV infection in primiparous gilts immunized with a single-dose vaccine. PPV VLPs inhibited the replication and spread of PPV in primiparous gilts, which was confirmed by the detection of PPV DNA and infectious PPV in nasal and rectal swabs of challenged sows. These results suggest that VLPs-based PPV vaccine is a promising PPV vaccine candidate.

A double-sided mask process is used to define the micro actuators on a silicon-on-insulator (SOI) wafer. Then, an InGaN/GaN multilayer film was deposited on the surface of the above patterned SOI substrate by employed MBE technology. Thus, the final device consisting of comb-drive actuators, springs and micro-mirror is implemented to obtain the two-dimensional (2D) tuning effect of the mirror. The displacement response is characterized by applying voltage to the micro actuators. It shows an approximation linear relationship between the displacement and the square of applied voltage. And the influences of the cross-axis coupling effect are also measured and evaluated. Moreover, the luminous performances of the InGaN/GaN multiquantum well films were also studied by analyzing temperature-dependent and laser intensity-dependent PL spectra. The authors observed the localized state effect and/or band-gap narrowing effect which results in an S-shaped behavior with increasing temperature. The PL intensity and wavelength are also significantly affected by the excitation energy of laser.

Different waterlogging tolerance indices between 15 rapeseed (Brassica napus L.) cultivar materials were investigated after seed germinating and field waterlogging, in order to research the consistency of different methods, as well as the effects of waterlogging on yields. The results showed significant variation between the 15 materials. Anoxic germination under room condition resulted in great differences in kinds of waterlogging tolerant indexes, such as vigor index, survival rate, relative seedling length, relative root length and fresh weight; in the fields, plant growths were repressed seriously under waterlogging stress: root fresh weight, root length, aerial parts fresh weight, plant height, plant fresh weight, aerial parts dry weight, root dry weight and root/shoot ratio were decreased by various degrees. Meanwhile, physiological indicators like contents of soluble sugar, soluble protein, malondialdehyde (MDA) and proline, as well as activity of superoxidase (SOD) increased; on the other hand, plant height, number of effective branches, number of pods per plant, number of seeds per pod, yield per plant decreased significantly. Especially, the number of effective branches decreased by 31.81%~78.02% compared with control. 1000-seed weights were increased in some materials. Waterlogging tolerance capabilities varied between materials, but generally, waterlogging tolerant plants showed less genotype reduction. Correlation analysis showed that waterlogging tolerant indices of germinating seed in the room were significantly correlative to those physiological and morphological data in the fields, as well as the final yield characters. Unit conductivity was found significantly negatively correlated with yield per plant, while the relative vigor index was significantly positively correlated with yield per plant. This consistency demonstrated that different methods of determining waterlogging tolerance in rapeseed have the same conclusion. Moreover, it helps predicting the waterlogging tolerance of rapeseed cultivars in the lab conditions so that the breeding of the waterlogging tolerant cultivars can be accelerated in the future. © 2016 Friends Science Publishers

The dissolution of liquid nanodroplets is a crucial step in many applied processes, such as separation and dispersion in food industry, crystal formation of pharmaceutical products, concentrating and analysis in medical diagnosis, and drug delivery in aerosols. In this work, using both experiments and numerical simulations, we \textit{quantitatively} study the dissolution dynamics of femtoliter surface droplets in a highly ordered array under a uniform flow. Our results show that the dissolution of femoliter droplets strongly depends on their spatial positions relative to the flow direction, drop-to-drop spacing in the array, and the imposed flow rate. In some particular case, the droplet at the edge of the array can dissolve about 30% faster than the ones located near the centre. The dissolution rate of the droplet increases by 60% as the inter-droplet spacing is increased from 2.5 $\mu$m to 20 $\mu$m. Moreover, the droplets close to the front of flow commence to shrink earlier than those droplets in the center of the array. The average dissolution rate is faster for faster flow. As a result, the dissolution time $T_{i}$ decreases with the Reynolds number Re of the flow as $T_{i}\propto Re^{-3/4}$. The experimental results are in good agreement with numerical simulations where the advection-diffusion equation for the concentration field is solved and the concentration gradient on the surface of the drop is computed. The findings suggest potential approaches to manipulate nanodroplet sizes in droplet arrays simply by dissolution controlled by an external flow. The obtained droplets with varying curvatures may serve as templates for generating multifocal microlens in one array.

This chapter describes temporal and regional variation in pollution law enforcement in China. It shows that over time there has been an absolute growth in the frequency and stringency of sanctions. However, most importantly, we find that enforcement does not match pollution or industrial growth. And as such, the increasingly stringent national policies and extra investment have not sufficiently lifted enforcement to meet China’s environmental challenges. Moreover, central level influences have not yet been able to overcome the immense regional enforcement disparities. Instead we see a split is occurring, with stronger enforcement the richer coastal and municipal level provinces and weak enforcement in less developed regions. Potentially, this can create an institutionalized system of domestic environmental injustice where the rich can benefit from a better environment while outsourcing pollution to the poor.

Background Low concentrations of nonionic surfactants can change the physical properties of cell membranes, and thus and in turn increase drug permeability. Porcine circovirus 2 (PCV2) is an extremely slow-growing virus, and PCV2 infection of PK-15 cells yields very low viral titers. The present study investigates the effect of various nonionic surfactants, namely, Tween-20, Tween-28, Tween-40, Tween-80, Brij-30, Brij-35, NP-40, and Triton X-100 on PCV2 infection and yield in PK-15 cells. Result Significantly increased PCV2 infection was observed in cells treated with Tween-20 compared to those treated with Tween-28, Tween-40, Brij-30, Brij-35, NP-40, and Triton X-100 (p

A four-period InGaN/GaN (8 nm/48 nm) layered structure was deposited on a Si substrate with a surface-nitrified HfO2 film as a buffer layer (5 nm). A high In concentration of In0.36Ga0.64N was obtained in the InGaN layers. Red photoluminescence of 648 nm was observed from the layered structure. The internal quantum efficiency of the red emission from the InGaN layers on the surface-nitrified HfO2/Si was 52 %, which was more than 18 times larger than that on the Si substrate without HfO2. The surface-nitrified HfO2 provides another effective buffer layer to grow the InGaN/GaN layered structure on the Si substrate.

Multifunctional TiO2/ormosils organic-inorganic hybrid films that contain azobenzene and photosensitive groups are prepared by combining a low temperature sol-gel process and a spin-coating technique. The optical waveguide and the structural properties of the hybrid films are characterized and investigated respectively by different techniques. The photo-responsive properties of the hybrid films are induced by a photo-irradiation under UV light at a wavelength of 365 nm. Finally, micro-lens arrays are built in the hybrid films by using a UV soft imprint technique. These results indicate that the as prepared hybrid films with multifunctional photonic properties are promising candidates for integrated optics and photonic applications, which would allow the direct integration onto a single chip of the optical micro-elements and the optical data storage and optical switching devices.

Background: Telomerase activity is closely associated with the expression of human telomerase reverse transcriptase (hTERT) mRNA; although it can be induced in hepatocytes during liver regeneration, its dynamic change in patients with liver failure has remained unclear. Objectives: We investigated the variation and significance of hTERT mRNA expression in peripheral blood mononuclear cells (PBMCs) of the patients with liver failure. Patients and Methods: In this clinical experimental study, 76 Chinese patients were enrolled in the study between 2010 and 2012. The level of PBMCs hTERT mRNA was detected by relative quantitative real-time polymerase chain reaction (RT-PCR) in the samples taken before treatment and at seven-day intervals during a 28-day treatment period. The patients were divided into survivor and non-survivor groups according to the 3-months mortality after treatment. The dynamic variation of PBMCs hTERT mRNA was analyzed and its association with prognosis was assessed by the area under the receiver-operating characteristic curve. Results: The median level of PBMCs hTERT mRNA in survivors increased with treatment time and was significantly higher than the corresponding level in non-survivors after 14 days of treatment (P < 0.001). Subgroup analyses showed that the levels of PBMCs hTERT mRNA were remarkably higher in patients with acute-on-chronic liver failure than in those with chronic liver failure (P < 0.05). In patients with the same clinical type of liver failure, the level was markedly higher in survivors than in non-survivors after 14 days of treatment (P < 0.05); however, the levels were not significantly different between subgroups with different clinical type but the same prognosis. The sensitivity and specificity of PBMCs hTERT mRNA was high in evaluating the prognosis at day 14 and became much higher at days 21 and 28 post treatment. The expression of PBMCs hTERT mRNA had high sensitivity and specificity in evaluating the prognosis as early as day 14 post treatment and was significantly superior to the prognostic value of serum alpha-fetoprotein. Conclusions: The expression of PBMCs hTERT mRNA is closely associated with patient outcome, which indicates that hTERT mRNA in PBMCs might be useful as a prognostic biomarker of liver failure.

This paper, for the first time, makes an investigation into the impact of the dynamic changes in organizational forms of accounting firms on the result of audit, and the findings indicate that auditor will be more prudent to issue audit opinion, and therefore, its quality sees a considerable improvement, whose level of impact is obviously lower than that of non-Big 10" group.

Dans le cadre d'un developpement d'une prise de conscience de l'environnement aupres des eleves du primaire, l'auteur tente de comprendre quels sont les supports et les connaissances necessaires a l'accomplissement d'un tel objectif, et quelles sont les savoirs de base a inculquer a cette population d'eleves...

In this paper, the prison monitoring system is designed based on wireless sensor network technology. This system could not only monitor the relevant information about the vital signs of inmates in prison, but also record and check the physical condition of personnel, activities, status and location information at any time, preventing inmates from committing suicide or escaping, and discovering whereabouts of the criminals once the jailbreak occurred. The application of wireless sensor network technology in the prison monitoring system enables the monitoring of the prison more comprehensive, more scientific and more effective.

The states of gas accumulated at the liquid-solid interface are analyzed based on the continuum theory where the Hamaker constant is used to describe the long-range interaction at the microscopic scale. The Hamaker constant is always negative, whereas the gas spreading coefficient can be either sign. Despite the complexity of gas, including that the density profile may not be uniform due to absorption on both solid and liquid surfaces, we predict three possible gas states at the liquid-solid interface, i.e. complete wetting, partial wetting and pseudopartial wetting. These possible gas states correspond respectively to a gas pancake (or film) surrounded by a wet solid, a gas bubble with a finite contact angle, and a gas bubble(s) coexisting with a gas pancake. Typical thickness of the gas pancakes is at the nanoscale within the force range of the long-range interaction, whereas the radius of the gas bubbles can be large. The state of gas bubble(s) coexisting with a gas film is predicted theoretically for the first time. Our theoretical results can contribute to the development of a unified picture of gas nucleation at the liquid-solid interface.

Evaporation of multicomponent liquids plays a crucial role in industrial applications as well as biological and physical phenomena. We begin this thesis by discussing the importance of evaporation and describing the physicochemical hydrodynamics triggered by the evaporation of confined multicomponent liquids (Chapter 1). In Chapter 2, we study droplets containing water, glycerol, and colloidal particles using experiments, simulations, and analytical modelling. We show that the solutal Marangoni flow triggered by the evaporation of water leads to the formation of a ‘Marangoni ring’. However, we also show that surfactants and non-hydrodynamic interactions might be crucial to fully explain all the processes in this system. In Chapters 3 and 4, we study the formation of supraparticles created by evaporating ternary (Ouzo) droplets containing colloidal particles. In particular, we show that changing the size of individual particles changes the final shape of the supraparticle (Chapter 3). Moreover, we also show that changes in surface charge and hydration of the particles could even suppress the formation of supraparticles (Chapter 4). Thus, we can tune the formation of supraparticles in colloidal ternary droplets by carefully choosing the properties of the constituent particles. In Chapter 5, we show, using experiments and simulations, that adding glycerol slows down the evaporation of water from a capillary tube. Using a simplified analytical model, we show how diffusion, advection, size of the liquid column, and changes in interfacial concentration of water determine the different evaporation regimes. In short, we studied the spectacular and intriguing physicochemical hydrodynamics triggered by the evaporation of multicomponent liquids from two complementary systems: droplets and capillaries. These studies can be extended to produce novel multifunctional supraparticles, to have a deeper understanding of the drying of respiratory droplets, and for further technological advancements in inkjet printing.

Nanoscale oil droplets locating at solid-liquid interfaces significantly impact the interfacial properties, which are concerned in both industry applications and fundamental studies. This review article presents an overview of the current progress in nanodroplet research. We will start from the characterization of interfacial nanodroplets and the formation of interfacial nanodroplets by direct adsorption from emulsions and by the solvent exchange protocol. Then we will review the experimental and theoretical studies on the evolution of oil nanodroplets including spreading, dissolution, and detachment. We will also cover the emerging applications of the interfacial nanodroplets in the fields of surface functionalization and nanostructure engineering, and particularly, highlight the potential application as capping agents to obtain architectures on microparticle surface. Finally we propose the challenges and the opportunities in this area. In our opinion, the nanodroplets have not only of high relevance to practical applications, but also serve as a model system for understanding many interfacial phenomena, such as phase separation and wetting on a microscopic scale. Refereed/Peer-reviewed

Interfacial nanobubbles (INBs) on a solid surface in contact with water have drawn widespread research interest. Although several theoretical models have been proposed to explain their apparent long lifetimes, the underlying mechanism still remains in dispute. In this work, the morphological evolution of INBs was examined in air- equilibrated and partially degassed water with the use of atomic force microscopy (AFM). Our results show that (1) INBs shrank in the partially degassed water while they grew slightly in the air-equilibrated water, (2) the three-phase boundary of the INBs was pinned during the morphological evolution of the INBs. Our analyses show that (1) the lifetime of INBs was sensitive to the saturation level of dissolved gases in the surrounding water, especially when the concentration of dissolved gases was close to saturation, and (2) the pinning of the three-phase boundary could significantly slow down the kinetics of both the growth and the shrinkage of the INBs. We developed a one-dimensional version of the Epstein−Plesset model of gas diffusion to account for the effect of pinning. Refereed/Peer-reviewed

Herein, we report the synthesis of amphiphilic multi-star architectures consisting of discrete poly(methacrylic acid)-based core cross-linked star polymers joined together by polystyrene-grafted linear connectors by a combination of atom transfer radical polymerisation of protected macroinitiator precursors and a copper-catalysed azide-alkyne cycloaddition grafting-to approach. The anisotropic multi-star architectures, which were obtained as individual di- and tri-star polymers with segregated hydrophobic and hydrophilic domains, undergo aggregation in apolar solvents resulting in the formation of large nanometre-scale vesicles. The self-assembling behaviour of these large amphiphilic multi-star polymers (M-w=869-1097kDa) was studied using dynamic light scattering, transmission electron microscopy, and atomic force microscopy. Refereed/Peer-reviewed