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Metal oxides containing La, Mn, and Co cations can catalyze oxygen reduction reactions (ORRs) in electrochemical processes. However, these materials require carbon support and optimal interactions between both compounds to be active. In this work, two approaches to prepare composites of La-Mn-Co-based compounds over carbon xerogel were developed. Using sol-gel methods, either the metal-based material was deposited on the existing carbon xerogel or vice versa. The metal oxide selected was the LaMn0.7Co0.3O3 perovskite, which has good catalytic behavior and selectivity towards direct ORRs. All the as-prepared composites were tested for ORRs in alkaline liquid electrolytes and characterized by diverse physicochemical techniques such as XRD, XPS, SEM, or N2 adsorption. Although the perovskite structure either decomposed or failed to form using those in situ methods, the materials exhibited great catalytic activity, which can be ascribed to the strengthening of the interactions between oxides and the carbon support via C-O-M covalent bonds and to the formation of new active sites such as the MnO/Co heterointerfaces. Moreover, Co-Nx-C species are formed during the synthesis of the metal compounds over the carbon xerogel. These species possess a strong catalytic activity towards ORR. Therefore, the composites formed by synthesizing metal compounds over the carbon xerogel exhibit the best performance in the ORR, which can be ascribed to the presence of the MnO/Co heterointerfaces and Co-Nx-C species and the strong interactions between both compounds. Moreover, the small nanoparticle size leads to a higher number of active sites available for the reaction.

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Overcoming the instability and poor recyclability during the practical applications of contaminant scavengers is a challenging topic. Herein, a three-dimensional (3D) interconnected carbon aerogel (nZVI@Fe2O3/PC) embedding a core-shell nanostructure of nZVI@Fe2O3 was elaborately designed and fabricated via an in-situ self-assembly process. The porous carbon with 3D network architecture exhibits strong adsorption towards various antibiotic contaminants in water, where the stably embedded nZVI@Fe2O3 nanoparticles not only serve as magnetic seeds for recycling, but also avoid the shedding and oxidation of nZVI in the adsorption process. As a result, nZVI@Fe2O3/PC efficiently captures sulfamethoxazole (SMX), sulfamethazine (SMZ), ciprofloxacin (CIP), tetracycline (TC) and other antibiotics in water. In particular, an excellent adsorptive removal capacity of 329 mg g-1 and a rapid capture kinetics (99% of removal efficiency in 10 min) under a wide pH adaptability (2-8) are achieved using nZVI@Fe2O3/PC as an SMX scavenger. nZVI@Fe2O3/PC displays exceptional long-term stability given that it shows excellent magnetic property after it is stored in water solution for 60 d, making it an ideal stable scavenger for contaminants in an etching-resistant and efficient manner. This work would also provide a general strategy to develop other stable iron-based functional architectures for efficient catalytic degradation, energy conversion and biomedicine.

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Utilizing ionic liquids (ILs) with low flammability as the precursor component for a gel polymer electrolyte is a smart strategy out of safety concerns. Solvate ionic liquids (SILs) consist of equimolar lithium bis(trifluoromethylsulfonyl)imide and tetraglyme, alleviating the main problems of high viscosity and low Li+ conductivity of conventional ILs. In this study, within a very short time of 30 s, a SIL turns immobile using efficient and controllable UV-curing with an ethoxylated trimethylolpropane triacrylate (ETPTA) network, forming a homogeneous SIL-based gel polymer electrolyte (SGPE) with enhanced thermal stability (216 °C), robust mechanical strength (compression modulus: 1.701 MPa), and high ionic conductivity (0.63 mS cm-1 at room temperature). A Li|SGPE|LiFePO4 cell demonstrates high charge/discharge reversibility and cycling stability with a capacity retention rate of 99.7% after 750 cycles and an average Coulombic efficiency of 99.7%, owing to its excellent electrochemical compatibility with Li-metal. A close-contact electrode/electrolyte interface is formed by in situ curing of the electrolyte on the electrode surface, which enables the pouch full cell to work stably under the conditions of cutting/bending. In view of the excellent mechanical, thermal, and electrochemical performances of SGPE, it is believed to be a promising gel polymer electrolyte for constructing high-safety lithium-ion batteries (LIBs).

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Phenanthrene (PHE), as one of representative polycyclic aromatic hydrocarbons (PAHs) can cause serious adverse effects on human health, developing effective adsorbents to alleviate PHE contamination is in urgent demand. A novel Fe3O4-SiO2-Dimethoxydiphenylsilane (Fe3O4-SiO2-2DMDPS) nanocomposite was fabricated from encapsulation and grafting process. Magnetic Fe3O4 nanoparticles were served as preliminary matrix material, SiO2 was used to link the magnetic oxide and provide hydroxyl groups for proceeding the silane coupling reaction subsequently, and the aromatic rings in DMDPS could provide active sites for PHE adsorption via π-π interaction. SEM-EDS, TEM, BET, VSM, XRD, FTIR, Raman, Zeta potential, and XPS techniques were used to characterize magnetic nanocomposite. The prepared Fe3O4-SiO2-2DMDPS exhibited an excellent adsorption performance towards PHE, it could maintain 75.97% adsorption capacity after four regeneration cycles. Homogeneous adsorption acted crucial role in the whole adsorption process and film diffusion was the rate-controlling procedure. Theoretical calculations put forward the most favorable bonding modes between Fe3O4-SiO2-2DMDPS and PHE molecules, confirmed the π-π interaction was valid and it usually existed in the form of parallel-displaced. This work might aid us to develop effective modification strategy for Fe3O4 nanoparticles and expand its application in the PAHs removing field.

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Nanomolar concentrations of NH2OH in natural water sources were determined using an Fe3+ oxidation method. A pH of 2.35 - 2.50 was used, which was adjusted by adding a chloroacetate buffer. Equal amounts (1.0 mL) of the chloroacetate solution and ferric chloride solution were added to the water sample (70 mL) to oxidize NH2OH to N2O. The resulting N2O in the sample water was then quantified by headspace analysis using a gas chromatograph with an electron-capture detector (ECD), where a limit of detection of 0.2 µgN L-1 (14 nmol L-1) was achieved. This method was successfully applied to samples of freshwater, brackish water, and seawater, and despite the various salinities no interfering substances were observed. Furthermore, NH2OH was successfully detected in samples collected from the Hii River and Lakes Shinji and Nakaumi (Shimane Prefecture, Japan). In addition, the proposed method was also applicable to samples rich in organic substance derived from phytoplankton.

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The generation of virus-mimetic nanoparticles has received much attention in developing a new vaccine for overcoming the limitations of current vaccines. Thus, a method, encompassing most viral features for their size, hydrophobic domain and antigen display, would represent a meaningful direction for the vaccine development. In the present study, a polymer-templated protein nanoball with direction oriented hemagglutinin1 on its surface (H1-NB) was prepared as a new influenza vaccine, exhibiting most of the viral features. Moreover, the concentrations of antigen on the particle surface were controlled, and its effect on immunogenicity was estimated by in vivo studies. Finally, H1-NB efficiently promoted H1-specific immune activation and cross-protective activities, which consequently prevented H1N1 infections in mice.

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In order to improve the dispensability of graphene oxide (GO) in waterborne polyurethane (WPU), sulfonated graphene (SGO) with superior dispersity was prepared by modifying graphene oxide with sodium 2-chloroethane sulfonate to introduce hydrophilic sulfonic groups into the structure. SGO/WPU composites were prepared using isophorone diisocyanate (IPDI), polytetramethylene ether glycol (PTMEG 2000), dimethylolpropionic acid (DMPA) and SGO as raw materials. The influence of SGO content on composite properties were investigated. The structure and morphology of SGO and SGO/WPU composites were characterized by infrared spectroscopy, X-ray diffractometry and transmission electron microscopy etc. Their mechanical properties and wear resistance were analyzed as well. The experimental results showed that SGO was successfully grafted onto polyurethane macromolecule by an in situ method and, with the introduction of sulfonic groups, the interfacial compatibility of GO and PU was improved significantly so that SGO evenly dispersed into WPU. The SGO that was grafted onto WPU macromolecules exhibited layered morphology with nanometers in the WPU matrix. With increasing SGO content, the tensile strength and the wear resistance of the film increased, but the addition of more than 0.8 wt % SGO yielded unfavorable results. When the added amount of SGO was 0.8 wt % of WPU, the tensile strength of the composite film was 46.53% higher than that of the blank group, and the wear resistance of the film was remarkably improved, which was due to a strong interaction between the SGO and WPU phases. Thus, the conclusion can be drawn that appropriate amount of SGO addition can enhance the mechanical properties of SGO/WPU composite film.

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We developed a method for quantifying trace NH2OH in brackish- and sea-water samples. Previously reported methods applicable to fresh water cannot be applied to such samples. We determined that interference in seawater owing to the bromide ion can be removed by the addition of phenol. In our procedure, phenol and hypochlorite solutions were added to a sample solution to oxidize NH2OH to N2O. N2O in the sample was then quantified by headspace analysis. The method is not affected by the salt content or ammonia, nitrate, or nitrite at concentrations of 300 µgN L-1 or less. It has a limit of detection of 0.2 µgN L-1, and can quantify NH2OH in natural water samples with a wide range of salinity. It was applied to samples from Lake Nakaumi, a brackish lake located in the eastern part of Shimane Prefecture, Japan.

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In order to sustain rapid expansion in the field of biocomposites, it is necessary to develop novel fillers that are biodegradable, and easy to disperse and obtain. In this work, gliadin particles (GPs) fabricated through an in situ method have been reported as fillers for creating chitosan (CS)-based biocomposite films. In general, the particles tend to agglomerate in the polymer matrix at high loading (approximately >10%) in the biopolymer/particles composites prepared by the traditional solution-blending method. However, the micrographs of biocomposites confirmed that the GPs are well dispersed in the CS matrix in all CS/GPs composites even at a high loading of 30% in this study. It was found that the GPs could improve the mechanical properties of the biocomposites. In addition, the results of moisture uptake and solubility in water of biocomposites showed that water resistance of biocomposites was enhanced by the introduction of GPs. These results suggested that GPs fabricated through an in situ method could be a good candidate for use in biopolymer-based composites.

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In ruminant nutrition, peas are characterized by high protein solubility and degradability, which impair its protein value estimated by the official in situ method. Grinding can be used as a technological treatment of pea seeds to modify their nutritional value. The aim of this study was to compare the in situ method with an in vitro method on the same pea either in a coarse pea flour form (PCF) or in a ground pea fine flour form (PFF) to understand the effect of grinding. Both forms were also reground (GPCF and GPFF). PCF presented a lower rate of in vitro degradation than PFF, and more stable fermentation parameters (pH, ammonia, soluble carbohydrates) even if gas production was higher for the PCF after 48 h of incubation. In situ dry matter and protein degradation were lower for PCF than those for PFF; these differences were more marked than with the in vitro method. Reground peas were very similar to PFF. The values for pea protein digestible in the intestine (PDI) were higher for PCF than those for PFF. This study points out the high sensitivity of the in situ method to grinding. The study needs to be validated by in vivo measurements.

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This study explored the potential of partial least squares (PLS) and Fourier-transform infrared spectroscopy (FTIR) to predict rumen dry matter (DM) and neutral detergent fiber (NDF) degradation parameters of a wide range of feeds for ruminants, as an alternative to the in situ method. In total, 663 samples comprising 80 different feed types were analyzed. In situ DM and NDF degradabilities were determined as follows: effective degradability (ED), rumen soluble fraction (A), degradable but not soluble fraction (B), rate of degradation of the B fraction (C), and indigestible NDF (iNDF). Infrared spectra of dry samples were collected by attenuated total reflectance from 600 to 4000cm(-1). Feeds were randomly classified into 2 subsets of samples with representation of all feed types; one subset was used to develop regression models using partial least squares, and the second subset was used to conduct an external validation of the models. This study indicated that universal models containing all feed types and specific models containing concentrate feeds could provide only a relatively poor estimation of in situ DM degradation parameters because of compositional heterogeneity. More research, such as a particle size distribution analysis, is required to determine whether this lack of accuracy was due to limitations of the FTIR approach, or simply due to methodological error associated with the in situ method. This latter hypothesis may explain the low accuracy observed in the prediction of degradation rates if there was physical leakage of fine particles from the mesh bags used during in situ studies. In contrast, much better predictions were obtained when models were developed for forage feeds alone. Models for forages led to accurate predictions of DMA, DMB, NDFED, and NDF concentration (R(2)=0.91, 0.89, 0.85, and 0.79, standard error = 4.34, 5.97, 4.59, and 4.41% of DM, respectively), and could be used for screening of DMED, NDFC, and iNDF. These models relied on certain regions of the FTIR spectrum (900-1150 and 1500-1700cm(-1)), which are mainly compatible with absorption of plant cell wall components, such as cellulose, pectin, lignin, cutin, and suberin, but also with nonstructural carbohydrates and certain active compounds. In conclusion, FTIR spectroscopy could be considered a low-cost alternative to in situ measurements in feed evaluation.

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Genetic amniocenteses were performed in a series of 127 patients as a routine study. Samples from the patients were cultured by in situ method, flask method or both according to the state of amniotic fluid. The overall success rate of culture was 97.6% and no culture failure was observed in the flask method. It took 5 days first of all and 8.15 days average from set-up to harvest and there were 7.2 colonies per dish in in situ method. Therefore, it is suggested that in situ method which decreased the mean culture days and made clonal analyses possible, is a clinically available and even more reliable method in parallel with flask method in prenatal diagnosis.

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