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The use of low-cost photocatalysts to split water into H2 fuel via solar energy is highly desirable for the production of clean energy and a sustainable society. Here three-dimensional graphene oxide (3DG) porous materials were prepared by cross-linking graphene oxide (GO) sheets using aromatic diamines (benzidine, 2,2′-dimethyl-4,4′-biphenyldiamine, 4,4′-diaminodiphenylmethane) that reacted with the carboxyl groups of the GO sheets at room temperature. The prepared 3DG porous materials were used as efficient metal-free photocatalysts for the production of H2 via water splitting under full-spectrum light, where the photocatalytic activity was highly dependent on the cross-linker and the 3DG reduction level. It was also found that the 3DG prepared with benzidine as the linker demonstrated a significantly higher H2 evolution rate than the 3DGs prepared using 2,2′-dimethyl-4,4′-biphenyldiamine and 4,4′-diaminodiphenylmethane as the cross-linkers. The photoactivity was further tuned by varying the mass ratio of GO to benzidine. Among the prepared 3DG materials, 3DG-3, with an intermediate C/O ratio of 1.84, exhibited the highest H2 production rate (690 μmol g−1 h−1), which was significantly higher than the two-dimensional GO (45 μmol g−1 h−1) and the noncovalent 3DG synthesized by a hydrothermal method (128 μmol g−1 h−1). Moreover, this study revealed that the 3DG photocatalytic performance was favored by effective charge separation, while it could be further tuned by changing the reduction level. In addition, these results could prompt the preparation of other 3D materials and the application of new types of photocatalysts for H2 evolution.

The photocatalytic conversion of CO2 to fuels by light is of research interest owing to its relevance to environment and energy concerns. In this work, a hybrid H-TiO2–rGO–Re(bpy)(CO)3Cl composite consisting of a rhenium 2,2′-bipyridine compound, Re(bpy)(CO)3Cl, which was covalently grafted on reduced graphene oxide (rGO) and hydrogenated TiO2 (H-TiO2) was prepared. H-TiO2–rGO–Re(bpy)(CO)3Cl demonstrated high efficiency for visible light photo-conversion of CO2 into CO in triethanolamine/N,N-dimethylformamide (V:V = 1:9) solution with total turnover numbers larger than 580. In addition, the composite showed high stability with no leveling-off tendency after four catalytic experimental runs. The experimental results indicate that the suitable assembly of the Re(bpy)(CO)3Cl, rGO, and H-TiO2 components in the H-TiO2–rGO–Re(bpy)(CO)3Cl composite is necessary for the observed high performance of the catalyst for CO2 reduction under visible light irradiation.

Polymer-based composites with ceramic fillers could combine the advantages of both, which can be potentially used in electrical and electronic technology. In this work, the barium titanate (BaTiO 3 ) nanofibres and the core-shell structured BaTiO 3 @Al 2 O 3 nanofibres with Al 2 O 3 insulation layer coated on the BaTiO 3 surface were both prepared via the electrospinning method. The appropriate incorporation of the ceramic nanofibres effectively improves the dielectric properties and energy density of the polymer. Moreover, the poly(vinylidene fluoride- co -hexafluoropropylene)-based composite films with the three-layer sandwich structure were fabricated to further promote the dielectric properties. The results show that the outer two layers with a higher content of BaTiO 3 nanofibres can make more contribution to the improved permittivity of the composites. In addition, the introduction of the interlayer with low loading of BaTiO 3 @Al 2 O 3 nanofibres promotes the breakdown strength. This work gives rise to the potential in high energy storage applications.

This research aims to develop a composite photo-catalyst using recycled clay brick sands (RCBS) and nano-TiO2. The RCBS was sourced from construction and demolition wastes (C&DW). For comparison, river sands (RS) were also used. Both RCBS and RS were soaked in 0%, 0.5%, 1.0%, 2.5%, and 5.0% (by weight) nano-TiO2 solutions to produce RCBS based composite and RS based composite photo-catalysts. The amount of nano-TiO2 absorbed by RCBS and RS was then determined. The photocatalytic methyl orange removal and NOx removal activities of the prepared composite photo-catalysts were investigated. The results showed that the amount of nano-TiO2 absorbed by RCBS and RS increased with increasing the concentration of nano-TiO2 solution. However, a non-linear relationship between the photocatalytic activities and the amount of TiO2 absorbed by RCBS and RS was observed. The highest methyl orange and NOx removal were observed on the composite photo-catalysts soaked in 1.0% nano-TiO2 solutions. Interestingly, the optimal RCBS based composite photo-catalysts were even superior to pure nano-TiO2 in terms of both methyl orange removal (60%) and NOx removal (50%) under the same conditions. Overall, the developed composite photo-catalysts not only possess an enhanced photocatalytic activity, but also generate value-added recycling of RCBS in construction materials.

In this study, natural sepiolite samples were treated with hydrochloric and acetic acid solutions at three different concentrations (0.1 M, 0.5 M, and 1.0 M). The effect of acid treatment on the reactivity of natural sepiolite and the change in cement hydration following the addition of natural sepiolite were studied using X-ray diffraction, particle size distribution analysis, inductively coupled spectrometry, thermogravimetric analysis, and isothermal calorimetry. Although acid treatment leads to a slight decrease in the amorphous phase content in natural sepiolite, the reactivity of sepiolite increased. The results indicate that the increase in sepiolite reactivity most likely stemmed from the activation of the Si phase. In addition, acid-treated sepiolite can modify the hydration of cement during the early curing period and hinder the hydration of cement during the later curing period. The compressive strength of specimens with strong acid-treated sepiolite was higher compared with specimens with weak acid-treated sepiolite.

In this work, two new D-A-π-A perylene dyes featuring with cyanoacrylic acid and 2-(1,1-dicyanomethylene) rhodamine (DCRD) as the electron acceptor/anchoring group, respectively, in combination with a N-annulated perylene electron donor and a quinoxaline auxiliary acceptor were investigated for application in dye-sensitized solar cells (DSCs) and dye-sensitized photocatalytic hydrogen production. The results showed that the sensitizer with cyanoacrylic acid ( YFT-1 ) based DSCs showed a higher conversion efficiency of 7.58% under AM1.5 solar conditions. However, it was interesting that the sensitizer with DCRD ( YFT-2 ) sensitized Pt/TiO 2 photocatalysts displayed a higher rate of H 2 evolution of 83.5 μmol h −1 under visible-light irradiation with wavelength between 420 nm and 780 nm. This may be ascribed to less interface charge recombination and more effective interfacial electron transfer between photo-excited YFT-2 and TiO 2 in aqueous solution. This study demonstrates that YFT-2 containing DCRD anchoring group is a promising candidate to achieve high and stable activity of H 2 production.

Four kidneys from 2 young donors suffering from rhabdomyolysis were rejected for transplantation at the time of procurement because of their severely bruised and black gross appearance. A frozen section revealed a focal tubular injury filled with granular pigmented casts which an immunohistochemistry confirmed to be myoglobin. The 4 kidneys were transplanted successfully and all recipients recovered normal renal function with no delay. These cases indicate that kidneys with patchy black gross appearance caused by myoglobin casts secondary to rhabdomyolysis is not a contraindication for transplantation.

To alleviate the heavy burden on landfilling, construction and demolition wastes (C&amp, DWs) are recycled and reused as aggregates in cementitious materials. However, the inherent characteristics of recycled fine aggregates (RFA), such as the high crushing index and high-water absorption, magnify the reusing difficulty. Nevertheless, attributing to the high porosity and high level of calcium hydroxides existing in the old mortar, RFA is featured with a high specific surface area and a high alkalinity. These features are useful to augment the total photo-degradation of SO2 by nano-TiO2 (NT) intermixed mortar, leading RFA to be an excellent potential carrier to load nano-TiO2 and prepare the composite photocatalyst. Hence, this study proposed to load NT onto the surface of RFAs and river sands (RSs) (the control) by the soaking method, preparing composite photocatalysts denoted as NT@RFA and NT@RS, respectively. The prepared composite photocatalysts were then utilized as sands in photocatalytic mortar to evaluate for SO2 degradation. Experiments identified a 50% higher amount of NT was loaded onto the surface of FRA relative to the control. This higher loading amount plus higher alkalinity ultimately translated into a higher photocatalytic activity. In addition, the mortar containing NT@RFA exhibited 46.3% higher physiochemical absorption and 23.9% higher photocatalytic activity than that containing NT@RS. In addition, the durability, embodied by the reuse and anti-abrasive properties, of NT@RFA exceeded that of NT@RS. The overall findings reveal that the NT@RFA not only garners beneficial effect from the high porosity but also generates positive effect from the high alkalinity. Though a number of studies deal with building materials with NT, this study is the first to load NT onto RFA and prepare composite photocatalysts which were then used as fine aggregates in building materials. Consequently, this study proves the potential high-added-value reusability of RFA in green construction materials and provides a low-cost, high-efficiency approach to degrade atmospheric SO2.

Background: There is no effective therapy for BK virus (BKV) nephropathy (BKVN). Cyclosporine A (CsA) has a lower immunosuppressive effect than tacrolimus. In vitro studies have shown that CsA inhibits BKV replication. The present study aimed to evaluate the effectiveness of switching from tacrolimus to low-dose CsA in renal transplant recipients with BKVN. Methods: Twenty-four patients diagnosed with BKVN between January 2015 and December 2016 were included. Tacrolimus was switched to low-dose CsA, and patients were followed for 24 months. Primary end points were BKV clearance in blood and graft. Secondary end points were urine specific gravity, serum creatinine, and graft loss. Results: The viremia in all patients cleared at a mean of 2.7 ± 2.0 months after switching to CsA. Urine specific gravity at 3 months after switching to CsA increased significantly compared with that at diagnosis (P=0.002). The timing and trend of urine specific gravity increase was consistent with the timing and trend of blood and urine viral load decrease. Repeated biopsies at a median of 11.2 months (range: 9.1–12.5 months) after switching to CsA showed that 8 patients (42.1%) were negative for BKV, and 11 patients (58.9%) had a decrease in BKV load (P

The mechanical properties and setting time of magnesium oxysulfate cement (MOS) were evaluated in the context of three-dimensional printing. MOS samples with MgO-to-magnesium sulfate mole ratios ranging from 2 ~ 9 and four water-to-solid weight ratios ranging from 0.27 ~ 0.57 were developed. The initial and final setting time was ~30 and 40 min, respectively. Moreover, MOS was prepared for 3D printing. The MOS micro-structure was examined. The average pore diameter was less than 20 nm, and the total porosity ranged from 11.76 to 37.39%. The gel pore content (

One of the promising solutions for decreasing atmospheric CO2 is artificial photosynthesis, in which CO2 can be photoconverted into solar fuels. In this study, a rhenium complex Re(PyBn)(CO)3 Cl (PyBn=1-(2-picolyl)-4-phenyl-1H-1,2,3-triazole) was covalently grafted onto the surface of reduced graphene oxide (rGO). This was further combined with TiO2 to fabricate a novel catalyst composite TiO2 -rGO-Re(PyBn)(CO)3 Cl for CO2 photo-reduction. This hybrid composite demonstrated high selectivity conversion of CO2 into CO under xenon-lamp irradiation. Compared with the unsupported homogeneous catalyst Re(PyBn)(CO)3 Cl, the covalent immobilized catalyst composite TiO2 -rGO-Re(PyBn)(CO)3 Cl enhanced the turnover number six times and significantly improved catalyst stability. During the process of CO2 photo-reduction, intermediate species with lifetimes longer than hundreds of microseconds were observed and the formation of CO products was revealed using timeresolved infrared spectroscopy. A plausible mechanism for CO2 photo-reduction by the TiO2 -rGO-Re(PyBn)(CO)3 Cl catalyst composite has been suggested. The obtained results have implications for the future design of efficient catalyst composites for CO2 photo-conversion.

This study aims to clarify the role of bio-deposition in improving the properties of recycled concrete aggregate (RCA) to enhance its reusability. Two bio-deposition treatments were investigated (immersion and spraying). The physical properties, pore structure, and micro-morphology of the RCA were investigated both before and after treatment, and the compressive and flexural strength of mortars prepared with treated and untreated RCA were also analysed. In addition, the micro-mechanical properties of the hydration products of bio-calcium carbonate were determined. The results showed that the water absorption, porosity, and crushing values of treated RCAs were lower than those of untreated RCAs. The compressive and flexural strength of mortars made with untreated RCAs were lower than those of mortars with treated RCAs. The results show that bio-calcium carbonate and its hydration products have a positive effect on the interfacial transition zone of the mortars, thereby reducing crack widths and improving the micro-mechanical properties.

The coupled CO2–water curing technique has been used for curing Portland cement-based materials, enabling the cement/concrete products with rapid strength development and lower carbon footprints. However, there is still a lack of convincing understanding on the mechanism of the accelerated carbonation reactions of cement. This current work mainly focused on characterizing the C–S–H gel formed in the bulk cement paste prepared with a low water to cement ratio (w/c = 0.18) subjected to a coupled CO2–water curing regime, by using solid state 29Si NMR and infrared spectroscopy together with other common tools. The results indicated that the CO2 curing process led to the formation of C–S–H gel containing more Q2 species than that in the corresponding hydrated pastes. Prolonged CO2 curing incorporated more Al tetrahedra into the C–S–H gel. Meanwhile, both the amorphous carbonates and calcite were formed during the accelerated carbonation reactions, and the calcite crystals could serve as nuclei to accelerate the cement hydration at the early age. Excessive CO2 curing resulted in a deficiency of lime in solution, yielding a structurally modified C–S–H with the absence of interlayered Ca(OH)2, and longer silicate chains as well as a higher polymerization degree when compared to the C–S–H formed in the normally hydrated cement samples.

Female-released chemical signals are crucial clues for mate-searching males to locate and gain sexual receptivity of conspecific females. Abundant behavioral evidence indicates that female spiders release sex pheromones to guide mate-searching behavior of conspecific mature males. However, the chemical nature of spider pheromones is poorly understood. Females of the funnel-web spider, Allagelena difficilis, employ sit-and-wait tactics for mating. Field observations indicate that males leave their retreats to search for potential mates during the breeding season. Therefore, we investigated whether virgin females release a sex attractant to conspecific males and then explored the chemical nature of the female pheromone. Four fatty acids extracted from the female bodies (palmitic acid, linoleic acid, cis-vaccenic acid and stearic acid) constitute a multiple-component sex attractant to conspecific males in A. difficilis. Unexpectedly, mated females also produce the same fatty acids, but at trace levels. Two-choice experiments showed that males were significantly attracted by the blend of the four fatty acids in appropriate concentrations while avoiding the blend consisting of the same acids at very low concentrations, suggesting that mate-searching males are able to discriminate virgin females from mated females by the quantities of female-specific fatty acids in the funnel-web spider A. difficilis.

The exploration of an effective diabetic chronic wound healing process still remains a great challenge. Herein, we used gene overexpression technology to obtain synovial mesenchymal stem cells (SMSCs) and the miR-126-3p highly expressed SMSCs (SMSCs-126). The exosomes derived from miR-126-3p overexpressed SMSCs (SMSCs-126-Exos) with a particle size of 85 nm were encapsulated in hydroxyapatite/chitosan (HAP-CS) composite hydrogels (HAP-CS-SMSCs-126-Exos) as wound dressings. The SMSCs-126-Exos, CS and low-crystallinity HAP nanorods with a length of 200 nm and a diameter of 50 nm are uniformly dispersed within the whole composite hydrogel. The HAP-CS-SMSCs-126-Exos possess the controlled release property of SMSCs-126-Exos for at least 6 days. The released SMSCs-126-Exos nanoparticles stimulate the proliferation and migration of human dermal fibroblasts and human dermal microvascular endothelial cells (HMEC-1). At the same time, the migration and capillary-network formation of HMEC-1 are promoted through the activation of MAPK/ERK and PI3K/AKT. In vivo tests demonstrate that the HAP-CS-SMSCs-126-Exos successfully promote wound surface re-epithelialization, accelerate angiogenesis, and expedite collagen maturity due to the presence of HAP, CS and SMSCs-126-Exos. Therefore, the HAP-CS-SMSCs-126-Exos possess great potential application for diabetic chronic wound healing, and especially provide the possibility of using exosomes derived from modified cells as a new approach to bring wonderful functionality and controllability in future chronic wound therapy.

We measured urinary phthalate metabolites, including di-n-butyl phthalate (DnBP), di-isobutyl phthalate, benzyl butyl phthalate (BBzP), and di(2-ethylhexyl) phthalate (DEHP), from 178 school-aged children and their 284 family members using gas chromatography-mass spectrometry, and we calculated daily phthalate intakes. The highest median levels of phthalate metabolites were for mono-isobutyl phthalate in all participants except schoolchildren, where the highest levels were for mono-(2-ethyl-5-oxohexyl) phthalate (MEOHP). Comparing the schoolchildren with their parents, the schoolchildren had significantly higher urinary metabolites for MEOHP, mono-(2-ethyl-5-carboxypentyl) phthalate, and EDEHP. Regarding daily intakes, the schoolchildren had significantly higher daily intakes of DnBP, BBzP, and EDEHP. All phthalate metabolite and sums of metabolite levels in the schoolchildren were positively correlated with their mothers' levels, except for MEHP, whereas fathers were less correlated with their children. The DEHP intake in this study was higher than that of most other studies. Moreover, 10% of the children and 3% of the adults exceeded the Reference Dose (RfD) value (20 mu g/kg/day) of the U.S. Environmental Protection Agency, which indicates that it is important to focus on children's DEHP exposure because the children exceeded the RID more than adults among the same families who shared similar exposure sources. Our results will contribute to considerations of the regulations for some phthalates and the actual phthalate exposure levels in the Japanese population. (C) 2015 Elsevier GmbH. All rights reserved.

Metallic doping effectively extends the light response range of TiO2 photocatalysts from the ultraviolet (UV) to the visible region. We prepared Ce-doped TiO2 nanotubes (Ce-TiO2 NTs) using a sol–gel process followed by a hydrothermal treatment. The Ce-TiO2 NTs were characterized by X-ray diffraction, transmission electron microscopy, Brunauer–Emmett–Teller surface area, X-ray photoelectron spectroscopy, UV–Vis diffuse reflectance spectroscopy (UV–Vis DRS), and photoluminescence (PL) spectroscopy. Given that the optical absorption was extended to wavelengths of 600 nm, the Ce-TiO2 NTs demonstrated excellent photocatalytic activity for degrading methylene blue under visible light irradiation. Ce-TiO2 NTs with various amounts of Ce doping (0.06–0.40 g of cerium nitrate hexahydrate added during preparation) were tested, and the 0.12Ce-TiO2 NTs showed the highest photocatalytic activity, 7 times higher than that of P25. For their efficient photodegrading of dyes under visible light, these Ce-TiO2 NTs may be useful for waste water treatment.

Two organic donor-acceptor-π-acceptor (D-A-π-A) sensitizers (AQ and AP), containing quinoxaline/pyrido[3,4-b]pyrazine as the auxiliary acceptor, have been. Through fine-tuning of the auxiliary acceptor, a higher designed and synthesized photoelectric conversion efficiency of 6.02% for the AQ-based dye-sensitized solar cells under standard global AM1.5 solar conditions was achieved. Also, it was found that AQ-Pt/TiO2 photocatalysts displayed a better rate of H2 evolution under visible-light irradiation (420 nm

This paper aims to investigate the durability properties of recycled aggregate concrete treated with silane-based water repellent agents, since the high water absorption of recycled aggregate concrete is a major factor jeopardizing its durability. Different dosages of silane-based water repellent agents were either coated on the surface of the concrete (hereafter “surface silane treatment”) or integrally added into the concrete mixture (hereafter “integral silane treatment”). The mechanical and durability properties of the treated concrete were evaluated. It was found that integral silane treatment can improve the durability of recycled aggregate concrete, but may lead to reductions in compressive strength; surface silane treatment is more effective in improving the resistance of recycled aggregate concrete to capillary water absorption, carbonation and chloride penetration than integral silane treatment.

Phthalates are widely used as plasticizers in household products. Several studies have reported an association between phthalate exposure and an increased risk of allergies. The present study estimated phthalate exposure in children aged 6–12 years and assessed potential correlations with allergies. House dust samples were collected from floors and multi-surface objects >35 cm above the floor. Urine samples were collected from the first morning void of the day. Daily phthalate intake (DIdust and DI) was estimated using both house dust and urinary metabolite concentrations. Exposure to di-2-ethylhexyl phthalate (DEHP) in floor dust was associated with parental-reported rhino-conjunctivitis. After stratification by gender, this trend was found to only occur in boys. Furthermore, urinary mono-isobutyl phthalate was inversely associated with parental-reported wheeze in boys. DIdust of benzyl butyl phthalate (BBzP) and DEHP were significantly correlated with DI_BBzP and DI_DEHP, respectively. These correlations were stronger with floor than with multi-surface dust. Our results suggest that, among Japanese children, house dust from low surfaces, such as living room floors, might play a meaningful role in the indoor environmental exposure pathway for BBzP and DEHP. Keywords: Allergy, Child, Daily intake, House dust, Phthalates, Urinary metabolites

Using cement-based building materials as a matrix for nano-photocatalysts is an important development for the large scale application of photocatalytic technologies. Air pollution mitigation and self-cleaning surface are two major applications of photocatalytic building materials. In this study, a comparison was made to evaluate the performance of TiO 2 modified concrete surface layers for NO x and VOC degradation. The self-cleaning performance of TiO 2 modified self-compacting mortars (SCM) developed for decorative applications was also evaluated. The results show that the photocatalytic conversion of toluene by the TiO 2 modified surface layer was not detected, although NO x could be effectively removed under the same conditions. The presence of toluene did not influence the NO x removal process. TiO 2 modified SCM were found to be effective in the discoloration of rhodamine B under UV and strong halogen light irradiation. The level of adsorption of the air contaminants onto the active sites of the cement-TiO 2 composite was identified to be the key factor determining the subsequent photocatalytic efficiency.

This paper reports an experimental study to improve the properties of recycled concrete aggregates (RCA) by their impregnation with polyvinyl alcohol (PVA). The effects of PVA on the development of strength and durability properties of the recycled aggregate concrete were evaluated. The experimental investigation was conducted in two parts. Firstly, the optimal concentration of PVA solution required to improve the recycled aggregates was determined. The RCA was soaked in 6%, 8%, 10%, 12% PVA solutions, and impregnation was conducted under a controlled laboratory environment. Density, crushing value (10% fines value), and water absorption of the PVA impregnated RCA (PI-RCA) were determined. Secondly, the slump, slump loss, compressive and tensile splitting strength, dimensional change (shrinkage) and chloride penetrability of the concretes prepared with the RCA that had been impregnated with the optimal (10%) PVA concentration were determined. It was found that the 10% fines value of the PI-RCA was higher, and the water absorption of the PI-RCA were lower when compared to the untreated RCA. The results show that there was not only an improvement in the mechanical properties of the concrete made with PI-RCA, but also the shrinkage of PI-RCA decreased while the resistance to chloride-ion penetration of the concrete produced increased.

It was found that, when the Baylis-Hillman reaction of arylaldehydes with methyl vinyl ketone was carried out at below -20 °C in the presence of boron (III) tribromide or titanium (IV) bromide using a catalytic amount of Lewis base such as amine, the brominated compounds and the Baylis-Hillman adducts could be obtained as the major products in good yields for various aryl aldehydes. But at room temperature, the elimination products were the major products. In addition, the palladium catalyzed allylic substitution reactions of the elimination products were also examined.

The interfacial electron transfer processes between a fluorescent water-soluble perylene diimide dye (WS-PDI) and TiO 2 nanoparticles were investigated using single-molecule fluorescence spectroscopy. Based on the single-molecule fluorescence spectral measurements, it was suggested that the local environment and/or the structural conformation of single WS-PDI molecules play important roles in the efficiency of the electron injection from WS-PDI in the singlet excited state to TiO 2 . The observed single-molecule fluorescence blinking behavior was interpreted in terms of the interfacial electron-transfer dynamics between the single WS-PDI molecules and TiO 2 nanoparticles.

The objective of the study was to investigate the feasibility of a single-dose hepatitis B vaccine based on three kinds of poly (D, L)-lactide-co-glicolide acid (PLGA) microspheres. PLGA microspheres loaded with recombinant hepatitis B surface antigen (HBsAg) were formulated using a double emulsion microencapsulation technique. The pharmaceutical characteristics of size, surface morphology, protein loading efficiency, antigen integrity, release of HBsAg-loaded PLGA microspheres and degradation of the polymer in vitro were evaluated. The degradation of the polymer corresponded with the composition of the polymer (lactide/glycolide ratio), molecular weight of the polymer (viscosity) and morphology of the microspheres. These PLGA microspheres were able to continuously release antigen under conditions that mimic the environment in vivo. The single subcutaneous injection of HBsAg-loaded PLGA50/50 microspheres, PLGA75/25 microspheres and a mixture of PLGA50/50, PLGA75/25, and PLGA50/50-COOH microspheres in mice resulted in comparable serum antibody titers to those of three injections of the conventional aluminum adjuvant formulated HBsAg vaccine. Based on these findings in vitro and in vivo, it was concluded that HBsAg was successfully loaded into the PLGA microspheres, which can auto-boost an immune response, and the HBsAg-loaded PLGA microsphere is a promising candidate for the controlled delivery of a vaccine.

Phenolic compounds can be nitrated with 60% nitric acid (1.2 equiv.) in the presence of catalytic amounts of a Zr or Hf oxychloride complex and montmorillonite KSF to give the corresponding nitrated products in good yields in a heterogeneous catalytic system. The co-catalyst and montmorillonite can be easily recovered and reused in the next batch of nitration. This is a practical process for the nitration of phenolic compounds in a clean way. C Wiley-VCH Verlag GmbH & Co.

The Zr(OTf)(4)-catalyzed reaction of indole, 1-methylindole or pyrrole with alpha,beta-unsaturated ketone generated the corresponding trisindolyl-, tris(1-methylindolyl-), and trispyrrolylalkanes in moderate to high yields in the mixed solvent EtOH/H2O. (C) 2004 Elsevier Ltd. All rights reserved.

Phenolic compounds can be nitrated by 65% nitric acid in the presence of catalytic amounts of montmorillonite KSF and bismuth(III) nitrate to give the corresponding nitrated products in good yields in a heterogeneous phase. The co-catalyst of KSF and Bi(NO^3)^3 can be esily recovered and reused in the next batch of nitration.

The Friedel–Crafts reaction of anisole with acetic anhydride can be carried out in the presence of perfluorinated rare earth metal catalyst without organic solvent. Perfluorodecalin (C 10 F 18 , cis - and trans -mixture) can be used as a fluorous phase solvent for this reaction. Whereas, the reaction of N , N -dimethylaniline with acetic anhydride did not give the corresponding Friedel–Crafts reaction product. On the other hand, the Friedel–Crafts reaction of N , N -dimethylaniline with ethyl glyoxylate was also examined in the presence of perfluorinated Lewis acids. Three products were in fact formed at the same time.

The Baylis–Hillman reaction of aryl aldehydes with α,β-unsaturated ketones in the presence of titanium(IV) chloride can be promoted by oxy-compounds at room temperature, although they are not as effective as amines, chalcogenides, or quaternary ammonium salts. The oxy-compounds can be simple alcohols, ethers, and ketones. For aryl aldehydes having a strong electron-withdrawing group on the phenyl ring such as nitrobenzaldehyde or p-trifluoromethylbenzaldehyde, the chlorinated compound 1 is obtained as the major product. However, for other aryl aldehydes, the elimination compound 3 was formed predominantly. We also found that TiCl4·2THF or TiCl4·2Et2O complex is very effective for this reaction to give the chlorinated products in high yields at low temperature. A plausible mechanism is proposed.

A number of studies had been conducted on the activation of fly ash using gypsum and sodium sulfate. Anhydrite, another form of calcium sulfate, has not been used for this purpose. This paper presents an exploratory study on the effectiveness of anhydrite in activating fly ash cement systems. Anhydrite (10%) was added into cement mortars with up to 55% fly ash replacement. The prepared mortars were allowed to cure in steam at 65°C for 6 h before normal room temperature water curing. Significant strength increases (up to 70%) compared to the control mortars were observed as early as after 3 days curing. Improvements in the pore size distribution of the mortars were also observed due to the activation. The results of scanning electron microscopy (SEM) examination and quantitative X-ray diffraction (XRD) analysis show that, with accelerated curing, a large quantity of ettringite (AFt) was formed during the early stage of hydration of the anhydrite-activated fly ash cement pastes. This might be the main cause of the high early strength of the activated fly ash cement systems. A comparison was made using anhydrite and gypsum as activators. For an equivalent SO3 content, anhydrite is more effective in increasing the early-age strength of the cement/fly ash mortars, but less effective in increasing the later-age strength than gypsum.

In the Baylis–Hillman reaction of aldehydes with an α,β-unsaturated ketone, the chlorinated compound 1 was obtained as the major product using tributylphosphine as a Lewis base in the presence of titanium(IV) chloride, zirconium(IV) chloride or boron trichloride in dichloromethane at

The demand for phosphorus flame retardants (PFRs) has recently increased as an alternative to polybrominated diphenyl ether (PBDE). PFRs have been detected in house dust, but little is known about the concentrations of PFRs in private homes and the effects on human health. We measured the levels of 10 PFRs in indoor floor dust and upper surface dust from 128 Japanese dwellings of families with children in elementary school. The median (min–max) concentrations (μg/g) of PFRs were as follows: tris(2-butoxyethyl) phosphate (TBOEP), 30.88 (< 0.61–936.65); tris(2-chloro-iso-propyl) phosphate (TCIPP), 0.74 (< 0.56–392.52); and triphenyl phosphate (TPHP), 0.87 (< 0.80–23.35). These values exceeded 50% detection rates, and the rates are median over the LOD in floor dust. The concentrations (μg/g) of TBOEP 26.55 (< 0.61–1933.24), TCIPP 2.23 (< 0.56–621.23), TPHP 3.13 (< 0.80–27.47), tris(2-chloroethyl) phosphate (TCEP) 1.17 (< 0.65–92.22), and tributyl phosphate (TNBP) 0.74 (< 0.36–60.64) exceeded 50% detection rates in the upper surface dust. A significant positive correlation (P < 0.05) between the concentrations of TCIPP and TBOEP was shown in floor dust and upper surface dust (n = 48). Estimated median and 95th percentile daily intake was calculated for toddlers and elementary school children and was compared with reference dose values (RfD) from the literature. For TBOEP, the estimated 95th percentile intake from floor dust was 14% of RfD for toddlers and 4% for school children. The estimated intake from upper surface dust was somewhat lower. Estimated median intake of TBOEP and median intake for the other PFRs were less than 1% of the RfD. TBOEP, TCIPP and TPHP were the main PFRs in the dust. The median levels of PFRs are well below the RfD values.

In this paper, we describe the aza-Diels–Alder reaction of Danishefsky’s diene with arylaldehydes and aromatic amines in a fluorous phase. With perfluorodecalin (C10F18, cis- and trans-mixture) as the fluorous solvent and a perfluorinated rare earth metal salt [Sc(OSO2C8F17)3] (2.0 mol %) as a catalyst, this aza-Diels–Alder reaction can be performed many times without reloading the catalyst.

The nitration of aromatic compounds can be carried out in the presence of perfluorinated rare earth metal catalyst without halogenated organic solvent.

In the Baylis–Hillman reaction of aldehydes with an α,β-unsaturated ketone, the chlorinated compound 1 was obtained as the major product using tributylphosphine as a Lewis base in the presence of titanium(IV) chloride, zirconium(IV) chloride or boron trichloride in dichloromethane at

The Baylis–Hillman reaction of aryl aldehydes with α,β-unsaturated ketones in the presence of titanium(IV) chloride can be promoted by oxy-compounds at room temperature, although they are not as effective as amines, chalcogenides, or quaternary ammonium salts. The oxy-compounds can be simple alcohols, ethers, and ketones. For aryl aldehydes having a strong electron-withdrawing group on the phenyl ring such as nitrobenzaldehyde or p-trifluoromethylbenzaldehyde, the chlorinated compound 1 is obtained as the major product. However, for other aryl aldehydes, the elimination compound 3 was formed predominantly. We also found that TiCl4·2THF or TiCl4·2Et2O complex is very effective for this reaction to give the chlorinated products in high yields at low temperature. A plausible mechanism is proposed.

The nitration of aromatic compounds can be carried out in the presence of perfluorinated rare earth metal catalyst without halogenated organic solvent.

Airborne singlet oxygen (1O2) molecules, which are generated during the TiO2 photocatalytic reactions and diffused from the surface into air, were detected at the opposite surface using terrylenediimide (TDI) molecules at the single-molecule level. The novel 1O2 nanosensor, which has a detectable number of about 1000 1O2 molecules in 70 × 70 square micrometers, can easily detect the single 1O2 molecule at a distance of over 1000 micrometers from the place of its creation in ambient air.

In this paper, we describe a useful Mannich-type reaction in fluorous phase. By use of perfluorodecalin (C 10 F 18 , cis - and trans -mixture) as a fluorous solvent and perfluorinated rare earth metal salts such as Sc(OSO 2 C 8 F 17 ) 3 or Yb(OSO 2 C 8 F 17 ) 3 (2.0 mol%) as a catalyst, the Mannich-type reaction of arylaldehydes with aromatic amines and (1-methoxy-2-methylpropenyloxy)trimethylsilane can be performed for many times without reloading the catalyst and the fluorous solvent.

The Mannich-type reaction of imines with (1-methoxy-2-methylpropenyloxy)trimethylsilane and aza-Diels-Alder reaction of imines with Danishefsky's diene can be carried out in scCO(2) in the presence of lithium heptadecafluorooctanesulfonate which offer a way to synthesize beta-amino carbonyl compounds and nitrogen-containing six-membered ring compounds under environmentally benign conditions. (C) 2004 Elsevier Ltd. All rights reserved.

A novel mixed catalyst of LiClO4 (15% w/w), Yb(OPf)(3) (15% w/w, Pf = perfluorooctanesulfonyl), MoO3 (15% w/w) on silica gel for electrophilic aromatic nitration reaction has been explored. The nitration reactions were accomplished by this mixed catalyst and nitric acid under solvent-free conditions. Moreover, the mixed catalyst can be easily recovered from the aqueous layer by heating in an oven and reused for the next nitration reaction

In this paper, we describe a practical, useful electrophilic aromatic nitration process in fluorous phase by using perfluorodecalin (C10F18, cis- and trans-mixture) as a fluorous solvent and perfluorinated rare earth metal salt [Yb(OSO2C8F17)3] as a catalyst for the electrophilic aromatic nitration.

The Baylis-Hillman reactions of various aryl aldehydes with methyl vinylketone at temperatures below -20 o C using Lewis acids such as titanium (IV) chloride,boron (III) chloride or zirconium (IV) chloride in the presence of a catalytic amount ofselected amines used as a Lewis bases afford the chlorinated compounds 1 as the majorproduct in very high yields. Acrylonitrile can also undergo the same reaction to give thecorresponding chlorinated product in moderate yield. A plausible reaction mechanism isproposed. However, if the reaction was carried out at room temperature (ca. 20 o C), thenthe Z-configuration of the elimination product 3, derived from 1 , was formed as the majorproduct. Keywords: Titanium (IV) chloride; boron (III) chloride; zirconium (IV) chloride;Bayliss-Hillman reaction; halogenation; Lewis base, amine. Introduction The Baylis-Hillman reaction and related processes, typically catalyzed by DABCO or tertiaryphosphines, have become increasingly important in organic synthesis because the resulting adducts mayhave several functional groups available for numerous further transformations [1-5]. The major drawbacks