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Biosynthetic of silver nanoparticles (AgNPs) by using fungi has attracted much attention due to its high catalytic efficiency and environmentally friendly characteristic. However, a few studies have focused on the ecological toxicity effects of biogenic AgNPs on algae. Here, we first investigated the catalytic reduction of 4-nitrophenol (4-NP) by WZ07-AgNPs biosynthesized by Letendraea sp. WZ07. WZ07-AgNPs had significant catalytic activity with 97.08% degradation of 4-NP in 3.5 min. Then, the toxic effects of WZ07-AgNPs and commercial-AgNPs were compared by Chlorella pyrenoidosa growth, chlorophyll content, protein content, physiological, and biochemical indexes. The results demonstrated that the algal cell biomass of C. pyrenoidosa was differentially inhibited after exposure to different concentrations of AgNPs, which showed concentration dependence and time dependence. The 96h-EC

Potassium (K) has an important effect on the growth and development of plants. Banana contains high K content than many other fruits, and its plant requires more K nutrient in soil. However, the soil in the banana-producing areas in China is generally deficient in K. Therefore, understanding the mechanism of banana K absorption may assis in providing effective strategy to solve this problem. This study used two banana varieties with contrasting K tolerance, ‘Guijiao No. 1’ (low-K tolerant), and ‘Brazilian banana’ (low-K sensitive)to investigate K absorption mechanisms in response to low K stress through miRNA and mRNA sequencing analysis. Under low K condition, ‘Guijiao No.1’ showed higher plant height, dry weight, tissue K content and ATPase activity. Transcription factor analysis results showed that it was mainly concentrated in MYB, AP2-EREBP, bHLH, etc. The sequencing results showed that ‘Guijiao No. 1’ had 776 differentially expressed genes (DEGs) and 27 differentially expressed miRNAs (DEMs), and ‘Brazilian banana’ had 71 DEGs and 14 DEMs. RT-qPCR results showed that all miRNAs and mRNAs showed similar expression patterns with RNA-Seq and transcriptome. miRNA regulatory network was constructed by integrated analysis of miRNA-mRNA data. miR160a was screened out as a key miRNA, and preliminary functional validation was performed. Arabidopsis overexpressed miRNA160a reduced tolerance to low K, and inhibited phenotypical traits such as root length, and reduced K accumulation. The overexpressed miR160a had a targeting relationship with ARF10 and ARF16 in Arabidopsis. These results indicate that miRNA160a may regulate K absorption in bananas through the auxin pathway. This study provides a theoretical basis for further research on the molecular mechanism underlying the response of banana plants to low-K stress and for molecular breeding.

High-frequency digitally controlled dc–dc switching converters have many advantages, such as very fast transient response and high-power density. However, the studies of control strategies and algorithms specifically for high-frequency digitally controlled dc–dc converters are seldom reported. In this study, we propose a novel digital current-mode controller consisting of both output voltage and inductor current compensators for high-frequency dc–dc switching converters. The voltage compensator is designed based on the delta operator instead of the shift operator, which could improve the control accuracy and reduce hardware costs. Furthermore, the current compensator is designed using an advanced sampling predictive (ASP) control strategy to reduce the requirement of hardware processing speed, and in turn the hardware cost, and to eliminate the influences of noise caused by power switch commutations. Finally, a buck dc–dc switching converter with a switching frequency of 2 MHz is designed and implemented using the proposed digital current-mode controller on a field-programmable gate array (FPGA) platform. Our test results indicate that better control accuracy and lower hardware costs can be realized using the delta operator instead of using the shift operator. In addition, compared with the single digital voltage compensator, the proposed digital current-mode controller has better transient response performances. The control strategy and algorithm proposed in this study are especially effective for digitally controlled high-frequency dc–dc switching converters.

Acute liver injury resulting from several factors such as medication, food toxins, and herbal supplementation often leads to a severe health condition and makes treatment difficult; thereby, the prevention of acute liver injury remains a critical issue and is of great importance. In this study, we investigated the preventive effects of nobiletin (NOB) on a mouse model of concanavalin A (ConA)-induced acute liver injury. We observed that NOB (10 mg/kg) pretreatment of ConA-treated mice significantly lowered the levels of liver enzymes including alanine aminotransferase (ALT) and aspartate aminotransferase (AST), decreased the intracellular generation of reactive oxygen species (ROS), and suppressed the release of inflammatory cytokines such as tumor necrosis factor-α (TNF-α) and interferon-γ (IFN-γ). Pathological data suggested that pretreatment with NOB ameliorated ConA-induced liver damage by promoting proliferation and alleviating apoptosis of hepatocytes. Furthermore, significant suppression of the c-Jun-activating kinase (JNK) signal was also observed in NOB-pretreated liver tissues compared with that of ConA treatment only. In addition, an

The intestinal epithelium barrier functions to protect human bodies from damages such as harmful microorganisms, antigens, and toxins. In this study, we evaluated the protective effect and molecular mechanism of a dominant polymethoxyflavone nobiletin (NOB) from tangerine peels on intestinal epithelial integrity. The results from transepithelial electrical resistance (TEER) suggested that NOB pretreatment counteracts epithelial injury induced by inflammatory cytokines (TEER value in 48 h: vehicle, 135.6 ± 3.9 Ω/cm2; TNF-α + IL-1β, 90.7 ± 0.5 Ω/cm2; 10 μM NOB + TNF-α + IL-1β, 126.1 ± 0.8 Ω/cm2; 100 μM NOB + TNF-α + IL-1β, 125.3 ± 0.5 Ω/cm2. P < 0.001). Clinical and pathological test results suggested that administration of NOB effectively alleviates intestinal barrier injury induced by dextran sulfate sodium (DSS) as evidenced by the length of colon villi on day 7 (control, 253.7 ± 4.8 μm, DSS 131.6 ± 4.6 μm, NOB + DSS, 234.5 ± 5.1 μm. P < 0.001). Interestingly, when screening tight junction molecules for intestinal barrier integrity, we observed that independent treatment with NOB sharply increased claudin-7 levels (ratio of claudin-7 over GAPDH: control, 1.0 ± 0.06; DSS, 0.02 ± 0.001; NOB + DSS, 0.3 ± 0.07. P < 0.001), which was previously suppressed upon DSS stimulation. Furthermore, hepatocyte nuclear factor 4α (HNF-4α) transcriptional regulation of claudin-7 contributed to intestinal barrier homeostasis. Therefore, our study suggests potential intestinal protective strategies based on polymethoxyflavones of aged tangerine peels.

In this paper, a backpropagation (BP) neural network controller trained using PID for digitally-controlled DC-DC switching converters is proposed to improve the transient response performance. To reduce the hardware cost and power consumption, only one BP neural network controller is used in the proposed controller, which is trained to learn the PID control algorithm and obtain the optimal control coefficients to fit the input-output relationship adaptively under different operating points. Furthermore, the proposed controller uses a single-hidden-layer BP neural network to reduce the computing time. Then, a buck DC-DC switching converter with the proposed controller is designed and realized on the field programmable gate array and printed circuit board. The experimental results indicated that it yields a better transient performance in a DC-DC switching converter than does a conventional neural network PID controller that contains two sub-controllers: the settling time is improved by at least 50% and the hardware resources required for a PID compensator are saved.

A new pulse width modulation (PWM)-based digital control for single-inductor multi-output (SIMO) DC–DC converters operating in continuous current mode (CCM) is proposed in this paper. To reduce the complexity of the control system and the hardware cost, only one digital-proportion-integration-differentiation (D-PID) compensator is used for the SIMO converters, and an idle period is introduced between each phase of the converters to reduce cross-regulation. Then, a SIMO buck DC–DC switching converter using the proposed control with two outputs is designed and implemented on a field-programmable gate array (FPGA) platform. The test results indicated that this SIMO converter can convert an input of 5V to 1.8 V and 2 V. Load transient measurements demonstrate that the cross-regulation is 0.13 mV/mA with a 300-mA load current change at output 1, and 0.04 mV/mA with a 500-mA load current change at output 2.

Milk phospholipids have been used as functional ingredients in foods. However, there have been no reports on how the polarity of lipids affects their digestibility. This study aims to isolate milk phospholipids from dairy products, to characterize them chromatographically, and assess their digestibility and antioxidant activities in vitro. The results revealed that their lipolysis reaction rate constants were significantly different ( p 0.05 ) between milk phospholipids and triacylglycerols, and thus the degradation of both lipids complied with first-order reaction kinetics. Furthermore, the cellular uptake of milk phospholipids was determined with HT-29 cell model, and they were not found to be absorbed intact during intestinal digestion. Milk phospholipids exhibited significant antioxidant activity in vitro, while their cellular antioxidant activity was very limited. The results of this study provide useful information for the design of milk phospholipid-based carrier systems.

Increasing health-promoting effects of resveratrol and its molecular structural analogues have been discovered, and the acting mechanism has been explored. However, the activity comparison of such compounds in targeting macrophage-related inflammation associated with neurodegenerative diseases remains untouched. In this study, we evaluated the activation and polarization transition of lipopolysaccharide (LPS)-stimulated BV-2 mouse microglial macrophages exposed to resveratrol (RES) and its analogues pterostilbene (PTE), oxyresveratrol (ORES), acetyl-trans-resveratrol (ARES), and trans-2,3,5,4'-tetrahydroxystilbene-2-O-glucopyranoside (TSG). At 10 μM, all of the five stilbene compounds have effectively suppressed the LPS-stimulated BV-2 cell release of proinflammatory mediators such as NO, TNF-α, iNOS, IL-1β, and IL-6. Mechanism study elucidated that they exert anti-inflammatory effects through MAPKs (ERK1/2, JNK, and p38) and NF-κB signaling pathways. Further investigation in treating BV-2 cells with resveratrol and its analogues revealed the reversal of LPS-induced phenotype molecules from M1 (iNOS, IL-1β, IL-6, and CD86) to M2 (Arg1, CD163, and IL-10) subtypes, manifesting that these five stilbenes suppressed inflammation through modulating the polarized phenotypes of BV-2 microglia. Most importantly, PTE demonstrated the most potent inhibitory activity among these five stilbene compounds. Therefore, this study not only highlights microglia-induced inflammatory responses as a potential therapeutic target but also suggests future insights in considering the options of nutraceutical development for resveratrol and its analogues.

In this study, mushroom stems were separated from the fruiting body of two edible mushrooms, white button mushroom (WB, Agaricus bisporus) and oyster mushroom (OY, Pleurotus ostreatus), and their functionalities were compared in wheat flour noodles at fortification levels of 5, 10, 15%. The inclusion of WB led to higher protein content than OY, which had more dietary fibre, especially insoluble dietary fibre. The fortification of mushrooms decreased the area under the curve (AUC) of reducing sugars released during in vitro digestion significantly (p

Pterostilbene (PTE) is broadly found in berries and has antioxidant and anti-inflammatory properties. To examine the effect of PTE on acute liver injury, mice were administrated PTE prior to concanavalin A (ConA). The mice were divided into the following groups: (i) vehicle control, (ii) ConA alone, (iii) ConA with PTE at 10 mg kg-1 (PTE low dose, PTL), and (iv) ConA with PTE at 40 mg kg-1 (PTE high dose, PTH). After the ConA challenge, the mice showed prompt induction of intrahepatic IFN-γ and TNF-α, followed by tissue factor (TF), which aggravated the fibrin deposition and massive liver necrosis. However, these effects were significantly counteracted by the PTE pretreatment. Furthermore, PTE reversed the phosphorylation of ConA-induced intrahepatic inflammatory kinases including JNK, ERK1/2, p38 and p65. Interestingly, PTE did not directly act on the hepatocytes, but inhibited intrahepatic macrophage accumulation and TF generation by inhibiting the activation of inflammatory p38 MAPK. These results suggest a promising avenue for the exploration of pterostilbene in improving acute liver injury.

A high precision delay locked loop (DLL) is designed for the readout circuit chip of a multi-channel cosmic ray muon detector in this paper. In order to decrease the system clock frequency and increase the measurement accuracy of muon signal, the DLL-based readout circuit architecture is preferred. The designed DLL has the features of wide dynamic clock range, high stability and high precision, which is implemented by a TSMC 0.18 μm mixed-signal CMOS process. The simulation results show that, the locking time of the DLL is 7 us, the locked frequency range is 30~60 MHz, and the statistical error of jitter is less than 150 ps. The performances of designed DLL are satisfied with the requirements of the readout circuit chip for a multi-channel cosmic ray muon detector.

A digital controller IC for DC-DC converters with high switching frequency is described and implemented by CSMC 0.18um CMOS process in this paper. The designed digital controller IC consists of a reference-voltage-programmable delay-line window type ADC, a current-mode compensator using Adjacent Cycle Sampling (ACS) control strategy, and a hybrid digital pulse-width modulator (DPWM) using the structure of counter comparator and delay-locked-loop delay line. The simulation results indicated that, a Buck DC-DC switching converters using the designed controller IC can convert an input from 5V to 1.8 V with 1Mhz switching frequency. The slew rate of the transient responses as load variation of 500 mA is 20mV/μs, at most.

A cosmic ray muon is a natural ray source with strong penetrability and has broad application prospects, especially in the monitoring of atmospheric temperature variations. In order to accurately deduce the atmospheric temperature variations, a global cosmic ray monitoring network is needed, and a low-cost, low-power, high-accuracy, efficient, and portable muon detection system is required. In this paper, we present the design of a 32-channel readout circuit chip for a muon detector with multi-angular acceptance. It can detect the information of incident muon rays, including both the arrival time and the pulse width of the signals. A novel readout circuit structure using a digital phase-locked loop (DLL) is proposed to decrease the frequency of the system clock without sacrificing the time measurement accuracy. For an input system clock of 50 MHz, a time resolution of ±1 ns is achieved by using a DLL generating 20 equally delayed clock signals. The designed readout circuit chip follows a 0.18 μm mixed-signal CMOS process, and the simulation results demonstrate the above-mentioned functions and performances.

Phospholipids are important ingredients in milk. They serve as bioactive components with processing functionalities, despite representing only a small proportion of total milk lipids. There has been increasing interest in vesicle properties and health effects of milk phospholipids. However, there are limited reports on industry-scale manufacturing of related commercial products. This contribution aims to elucidate the industrial processes of manufacturing milk phospholipid products including phospholipid extraction and fraction as well as summarizing determination assays of milk phospholipids. In addition to industrial production, this review elaborates on application aspects, such as the biological properties of milk phospholipids and their technical importance as delivery vesicles of liposomes and phytosomes. In addition, new insights on large-scale production of milk phospholipids and new applications such as phytosomes and antioxidant properties are discussed.

Oxidative stress leads to various diseases, including diabetes, cardiovascular diseases, neurodegenerative diseases, and even cancer. The dietary flavonol glycoside, hyperoside (quercetin-3-O-galactoside), exerts health benefits by preventing oxidative damage. To further understand its antioxidative defence mechanisms, we systemically investigated the regulation of hyperoside on oxidative damage induced by hydrogen peroxide, carbon tetrachloride, and cadmium in Saccharomyces cerevisiae. Hyperoside significantly increased cell viability, decreased lipid peroxidation, and lowered intracellular reactive oxygen species (ROS) levels in the wild-type strain (WT) and mutants gtt1∆ and gtt2∆. However, the strain with ctt1∆ showed variable cell viability and intracellular ROS-scavenging ability in response to the hyperoside treatment upon the stimulation of H2O2 and CCl4. In addition, hyperoside did not confer viability tolerance or intercellular ROS in CdSO4-induced stress to strains of sod1∆ and gsh1∆. The results suggest that the antioxidative reactions of hyperoside in S. cerevisiae depend on the intercellular ROS detoxification system.

Banana as an important economic crop worldwide, often suffers from serious damage caused by Fusarium oxysporum f. sp. Cubense. Arbuscular mycorrhizal (AM) fungi have been considered as one of the promising plant biocontrol agents in preventing from root pathogens. This study examined the effect of AM fungal inoculation on plant growth and differential expressions of growth- and defense-related genes in banana seedlings. Tissue-cultured seedlings of Brazilian banana (Musa acuminate Cavendish cv. Brail) were inoculated with AM fungus (Rhizophagus irregularis, Ri), and developed good mycorrhizal symbiosis from 4 to 11 weeks after inoculation with an infection rate up to 71.7% of the roots system. Microbial abundance revealed that Ri abundance in banana roots was 1.85×10(6) copies/ml at 11 weeks after inoculaiton. Inoculation improved plant dry weights by 47.5, 124, and 129% for stem, leaf, and the whole plant, respectively, during phosphate depletion. Among a total of 1411 differentially expressed genes (DEGs) obtained from the transcriptome data analysis, genes related to plant resistance (e.g. POD, PAL, PYR, and HBP-1b) and those related to plant growth (e.g. IAA, GH3, SAUR, and ARR8) were up-regulated in AM plants. This study demonstrates that AM fungus effectively promoted the growth of banana plants and induced defense-related genes which could help suppress wilt disease. The outcomes of this study form a basis for further study on the mechanism of banana disease resistance induced by AM fungi.

A high glycaemic index diet causes a rapid increase in blood sugar level and may lead to chronic metabolic disorders such as obesity and type 2 diabetes. Shiitake is rich in bioactive compounds. Wheat flour noodles were enriched with shiitake (Lentinus edodes) powder (cap, stem, whole) at different levels to investigate the effects of shiitake addition on the nutritional composition, physical and textural properties. In vitro digestion was conducted to determine the glycaemic glucose equivalents and bioaccessibility of antioxidants in digesta. The addition of 15% shiitake stem powder in the noodles resulted in a significant (p < 0.05) decrease in reducing sugars released after in vitro digestion. Digesta also exhibited cellular antioxidant ability on IEC-6 cells after H2O2-induced oxidative stress. These results show the potential beneficial use of shiitake, especially the stem, as a high-value ingredient to improve the nutritional profile and reduce the glycaemic index of foods.

Evidences have shown that phytosome assemblies are novel drug delivery system. However, studies of phytosomes in food applications are scarce. The characteristics of milk phospholipid assemblies and their functionality in terms of in vitro digestibility and bioavailability of encapsulated nutrients (ascorbic acid and α-tocopherol) were studied. The phytosomes were fabricated using ethanolic evaporation technique. Spectral analysis revealed that polar parts of phospholipids formed hydrogen bonds with ascorbic acid hydroxyl groups, further, incorporating ascorbic acid or α-tocopherol into the phospholipid assembly changed the chemical conformation of the complexes. Phospholipid-ascorbic acid phytosomes yielded an optimal complexing index of 98.52 ± 0.03% at a molar ratio of 1:1. Phytosomes exhibited good biocompatibility on intestinal epithelial cells. The cellular uptake of ascorbic acid was 29.06 ± 1.18% for phytosomes. It was higher than that for liposomes (24.14 ± 0.60%) and for ascorbic acid aqueous solution (1.17 ± 0.70%).

Milk fat has been used as functional ingredient in bread making. However, incorporation of enzymatically-treated milk fat into bread recipes and their effects on bread properties have not been explored. This study aims to ascertain the impact of lipase-treated milk fat on bread quality in comparison with untreated bread controls. As a result of lipase treatment, dough structure was strengthened, and loaf volume improved. In vitro digestion revealed that the glycaemic load of breads with lipase-treated milk fat was significantly lower than that of control samples ( p 0.05 ). In addition, lipase treatment reduced the crumb water activity. The study provides a novel and practical method to improve bread functionalities and lower product glycaemic response, without detrimental effects on the quality of the final products.

RuO2-TiO2/Ti electrodes with low-content La-doping are prepared by thermal decomposition method. The effect of La doping on their electrochemical performance upon UV illumination are investigated. The doped electrodes show higher density of cracks and rugosity in microscale on the surface than the undoped ones. They also have a negative shift of the onset potential of oxygen evolution from 1.1 V to 1.0 V and higher current intensity under UV irradiation as well. Electrochemical impedence spectroscopy analysis demonstrates a better electrical conductivity of the doped film. Electron paramagnetic resonance results show that the obtained La-doped TiO2 surface provides a higher density of oxygen vacancies. This anode also has 7.5% higher degradation rate of the methylene blue than La-undoped ones under UV irradiation. This is probably due to the increased surface rugosity and better electric conductivity, higher density of oxygen vacancies under UV irradiation by the doping of La ions.

Temporary plugging and diverting fracturing (TPDF) technique has been widely used in exploiting hydrocarbon resources in conventional/unconventional formations. The key to ensuring the success of this technique lies in the efficient plugging of the previously created fractures. However, the plugging characteristics of diversion agents influenced by the fracture geometry have not been efficiently investigated through experiments. In this study, the conventional true tri-axial hydraulic fracturing system was modified, then a series of investigative experiments were carried out and a novel experimental method was proposed to systematically investigate the plugging characteristics of diversion agents within the fracture. This method can not only investigate the effects of fracture geometry on the diversion agent distribution, plugging capacity, and plugging speed within fracture, but also optimize the diversion agent recipe for plugging various geometries fracture with different apertures, thus saving the dosage of diversion agents and fracturing fluids. Moreover, under certain conditions, as for the common four types of fractures i.e., distorted (type-Ⅰ) fracture, inclined and flat (type-Ⅱ) fracture, longitudinal and flat (type-Ⅲ) fracture, and transverse and flat (type-Ⅳ) fracture, the required ratio of diversion agent dosage for plugging is approximately 1:7:15:3.

This study reports the effects of addition of mushroom powder on the nutritional properties, predictive in vitro glycaemic response and antioxidant potential of durum wheat pasta. Addition of the mushroom powder enriched the pasta as a source of protein, and soluble and insoluble dietary fibre compared with durum wheat semolina. Incorporation of mushroom powder significantly decreased the extent of starch degradation and the area under the curve (AUC) of reducing sugars released during digestion, while the total phenolic content and antioxidant capacities of samples increased. A mutual inhibition system between the degree of starch gelatinisation and antioxidant capacity of the pasta samples was observed. These results suggest that mushroom powder could be incorporated into fresh semolina pasta, conferring healthier characteristics, namely lowering the potential glycaemic response and improving antioxidant capacity of the pasta.

Evapotranspiration (ET), including evaporation from soil and water surfaces and transpiration from vegetation, influences water distribution in the soil-plant-atmosphere continuum, especially in arid areas where water is a key limiting factor. Therefore, understanding the spatiotemporal dynamics of ET, including its two components of soil evaporation (Es) and vegetation transpiration (Ec), can be useful for water resource management and ecological restoration in arid regions. Based on ET data from 2002 to 2012, the spatiotemporal variations in ET were evaluated in the Shiyang River Basin in arid Northwest China. The results showed the following: (1) spatially, ET decreased from upstream of the Qilian Mountains to the middle and downstream, with a mean annual value of 316 mm, (2) temporally, ET showed a single peak curve throughout the year, with the highest value occurring in summer, (3) ET showed a downward trend (from 350 to 265 mm) before 2009 and thereafter increased (from 265 to 345 mm), and (4) water use efficiency, indicated by the ratio of Ec to ET, was low in the cropland, with a mean value of 50.9%. Further analysis indicates that decreases in ET are mainly caused by vegetation decreases, in contrast, ecological restriction measures and strict water resource management policies in the middle reaches of the basin led to ET increases. It is concluded that understanding ET and its two components can elucidate the connections between water and human society.

A series of S-containing organic–inorganic hybrid mesoporous silicas were synthesized and used as supports for the fabrication of supported gold nanoparticle catalysts. It was found that the location and structure of organic moieties in these mesostructures played a crucial role in the dispersion level of gold nanoparticles, and thus, had a significant effect on the catalytic performance. Under optimum conditions, the gold nanoparticles supported on a periodic mesoporous organosilica with bridging disulfide-ionic liquid moieties showed excellent catalytic performance and reusability in epoxidation of styrene in the presence of H2O2-acetonitrile. Moreover, whole epoxidation process and role of gold nanoparticles were proposed.

The stabilization of gold nanoparticles (GNPs) by disulfide groups linked to imidazolium chloride units in a periodic mesoporous organosilica of SBA-15 and their catalytic performances in the epoxidation of styrene were investigated. The mesoporous organosilica (PMO-SBA-15) was synthesized via a one-pot condensation process involving the assembly of ionic liquid silsesquioxane organic precursor containing disulfide group and tetraethoxysilane (TEOS) in the presence of P123 (EO20PO70EO20). Aqueous chloroaurate ions were in situ reduced by the silanol groups presented on the channel surface of the mesoporous organosilica to form GNPs that were subsequently captured by disulfide group to obtain Au-containing mesoporous organosilica (Au-PMO-SBA-15). The PMO-SBA-15 and Au-PMO-SBA-15 were characterized by XRD, 29Si MAS-NMR, FT-IR, UV–vis, TEM and N2 adsorption–desorption measurements. It was found that both PMO-SBA-15 and Au-PMO-SBA-15 had the typical characteristics of mesoporous SBA-15, and that the GNPs entrapped into the channels of Au-PMO-SBA-15 possessed mean size of ca. 1.8 nm. The Au-PMO-SBA-15 was used as a catalyst in the epoxidation of styrene. 95% of styrene conversion and 75% of selectivity to styrene epoxide were obtained over the novel Au-PMO-SBA-15 catalyst, which were higher than that over the reported nano-Au catalysts. Furthermore, the Au-PMO-SBA-15 could be conveniently recovered for recycled use without significant loss of catalytic activity and selectivity.

A convenient sonochemical method in preparation of gold nanoparticles capped by thiol-functionalized ionic liquid (TFIL) using hydrogen peroxide as a reducing agent was described in this paper. The obtained gold nanoparticles (GNPs) were characterized by ultraviolet–visible (UV–vis) absorption spectra, transmission electron microscopy (TEM) and Fourier transform infrared (FT-IR) spectra. It is found that the molar ratio of gold atom in chloroauric acid to thiol group in TFIL (Au/S) has great effects on the particles size and distribution of GNPs. The FT-IR spectra reveal that the function of thiol-containing ionic liquids is to form the bond of S–Au for stabilization of the gold cluster. Small gold nanoparticles size of 2.7 ± 0.3 nm with narrow uniform distributions can be obtained at the molar ratio of Au/S = 1:2 under ultrasound irradiation for 12 h. The reported method, which is performed in ionic liquid and hydrogen peroxide solution under ultrasound irradiation, is friendly to environment.