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In order to meet the navigation and positioning requirements of force inspection robot, a new technology based on improved VMD- + ACO algorithm is proposed. The main content of this technology is based on the research of improved VMD algorithm and ACO algorithm, through the comparison of VMD algorithm and improved VMD algorithm. By using ACO parameter optimization design and so on, the research means of improving VMD- + ACO algorithm navigation and positioning technology of electric inspection robot is finally established through experiments and analysis. The experiment result shows the following. The minimum iteration number of the improved ACO is 112, which is 24.32% less than that of the basic ACO. The mean value of the worst value and the optimal value of the function are equal to 0. It shows that the improved ACO has higher convergence precision and the number of iterations is significantly reduced. Conclusion. Based on the improved VMD- + ACO algorithm, it can meet the navigation and positioning requirements of electric inspection robot.

In order to improve the visual navigation performance in complex environment, a robust visual navigation method for substation inspection robot is proposed in this paper. Based on the robustness of hexagonal cone model to light changes, this method can solve the squeezing problem of navigation path in complex environment and reduce the interference caused by external light factors. Based on HM preprocessed images, semantic segmentation is carried out with deep convolutional neural network to obtain global features, local features, and multiscale information of images, so as to effectively improve the network recognition accuracy. The results show that the images after HM color space transformation and grayscale reconstruction can compress the color space while preserving the edge details, which is beneficial to the semantic segmentation network for further scene road recognition. Because the original structure of the network is not adjusted and the corresponding preprocessing layer is added, the size of the network model is relatively increased, but the reasoning speed of the original network is significantly improved, which is 16.4% on average.

Power transformers are an important asset of power companies. To improve the economic benefits of power companies, it is of great significance to accurately predict the lifecycle cost of each power transformer. Based on the historical operating data on 83 110 kV power transformers, this paper estimates the lifecycle costs of different transformers, and then creates a dataset containing the estimated lifecycle costs and multiple features of the transformers, namely, bid price, transformer capacity, no-load loss, load loss, silicon steel cost, copper wire cost, annual failure frequency (AFF) of major repair, and AFF of minor repair. Based on the dataset, a lifecycle cost prediction model was established for power transformers, which couples grey wolf optimization (GWO) with support vector regression (SVR). The GWO-SVR model was simulated on the prepared dataset. The results show that the mean absolute percentage error (MAPE) of the model was merely 5.20% on the test set. The proposed model provides a new method for power companies to accurately predict and evaluate the lifecycle cost of power transformers.

Oil sludge is one of the major industrial solid wastes from petroleum production and refining. Implementing the harmless and resource treatment of oily sludge is an urgent problem to be solved. In this paper, TiO2/bentonite was prepared by sol-gel method, which was characterized by scanning electron microscope (SEM), transmission electron microscope (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and infrared spectroscopy (FT-IR), and then used in the pyrolysis process of oily sludge. The addition of TiO2/bentonite give the best quality of pyrolysis oil; maximum oil recovery was achieved when setting the pyrolysis condition at 420°C for final pyrolysis temperature, 3 h for reaction time, 10°C/min for heating rate, 100 mL/min for nitrogen flow rate and 1% for catalyst dosage. Compared with the non-catalyst, oil recovery rate can be increased from 76.06% to 84.16%, the oil content of the residue decreased from 2.23% to 1.36%. The pyrolysis recovery oil was analysed by GC-MC, and the fractions of pyrolysis oil C6-C15 were increased by 27.84%. This shows that the addition of TiO2/bentonite decreased the carbon residue, increased oil recovery and improved product quality.

A solid-state pulse source is mainly formed by replacing the spark switch in a traditional pulse source with semiconductor switch device. Compared with conventional gas switch devices such as spark switches, semiconductor switch devices have the advantages of high work repetition frequency, long service life, small size, high efficiency, high reliability, easy control, and active shutdown. However, there are still problems, such as the solid-state switch being easily broken down by high voltage, the rising and falling edges of the pulse being slow, and the loss is enormous. In this paper, a solid-state pulse generator based on Marx with a chopping switch circuit is developed, which effectively solves the above problems. The pulse generator comprises DC power, a switching power circuit, a Marx circuit with a chopping switch, a serial port touch screen, and an optical fiber transmission circuit.

To assess the tibio-femoral contact forces before and after total knee arthroplasty (TKA) in patients with knee osteoarthritis (KOA) by three-dimensional (3D) finite element analysis (FEA) models and gait analysis.Two hospitalized patients with Kellgren-Lawrence grade IV varus KOA and two healthy subjects were enrolled in this study. Both patients underwent unilateral TKA. FEA models were established based on CT and MR images of the knees of the patients with KOA and healthy subjects. Gait analysis was performed using a three-dimensional motion capture system with a force plate. Three direction forces at the ankle joints were calculated by inverse dynamic analysis, which provided the load for the FEA models. The total contact forces of the knee joints were also calculated by inverse dynamic analysis to enable comparisons with the results from the FEA models. The total knee contact forces, maximum von Mises stress, and stress distribution of the medial plateau were compared between the patients and healthy subjects. The distributions of the medial plateau force at 2 and 6 months postoperatively were compared with the distributions of the forces preoperatively and those in the healthy subjects.During static standing, the medial plateau bore the most of the total contact forces in the knees with varus KOA (90.78% for patient 1 and 93.53% for patient 2) compared with 64.75 ± 3.34% of the total force in the healthy knees. At the first and second peaks of the ground reaction force during the stance phase of a gait cycle, the medial plateau bore a much higher percentage of contact forces in patients with KOA (74.78% and 86.48%, respectively, for patient 1; 70.68% and 83.56%, respectively, for patient 2) than healthy subjects (61.06% ± 3.43% at the first peak and 72.09% ± 1.83% at the second peak). Two months after TKA, the percentages of contact forces on the medial tibial plateau were 79.65%-85.19% at the first and second peaks of ground reaction forces during the stance phase of a gait cycle, and the percentages decreased to 53.99% - 68.13% 6 months after TKA.FEA showed that TKA effectively restored the distribution of tibio-femoral contact forces during static standing and walking, especially 6 months after the surgery. The changes in the gait were consistent with the changes in the contact force distribution calculated by the FEA model.

Sludge-based adsorbent (S-AB) converted by oily sludge can make full use of the precious resource. In this paper, oily sludge and discarded sawdust are used to prepare adsorbent through chemical activation. The adsorbent prepared is used to adsorb raw petroleum. Firstly, the most reasonable chemical activator ZnCl

The science of protein self-assembly has experienced significant development, from discrete building blocks of self-assembled nanoarchitectures to advanced nanostructures with adaptive functionalities. Despite the prominent achievements in the field, the desire of designing de novo protein-nanoparticle (NP) complexes and constructing dynamic NP systems remains highly challenging. In previous works, l-rhamnulose-1-phosphate aldolase (C98RhuA) tetramers were self-assembled into two-dimensional (2D) lattices via disulfide bond interactions. These interactions provided 2D lattices with high structural quality and a sophisticated assembly mode. In this study, we devised a rational design for RhuA building blocks to fabricate 2D functionalized protein lattices. More importantly, the lattices were used to direct the precise assembly of NPs into highly ordered and diverse nanoarchitectures. These structures can be employed as an excellent tool to adequately verify the self-assembly mode and structural quality of the designed RhuA crystals. The subsequent redesign of RhuA building blocks enabled us to predictably produce a novel protein lattice whose conformational dynamics can be controllably regulated. Thus, a dynamic system of AuNP lattices was achieved. Transmission electron microscopy and small-angle X-ray scattering indicated the presence of these diverse NP lattices. This contribution enables the fabrication of future NP structures in a more programmable manner with more expected properties for potential applications in nanoelectronics and other fields.

The incineration technology of oily sludge-based briquette makes great contributions to oily sludge treatment. In order to resolve these problems, air pollutants (SO2 and organic gas) emission and low incinerating rate during the briquette incineration, the effects of additives (CaCO3, CaO; K2CO3, Na2CO3, NaCl; KMnO4, KNO3, NaNO3; Fe2O3, KClO3) on the generating gas and incinerating rate during incineration were studied. The results show that CaCO3 is more effective than CaO for fixing sulphur into residue, and K2CO3 improved the sulphation efficiency of calcium-based additives, which is more useful than NaCl and Na2CO3 did. As for the incinerating rate of briquette, KMnO4 is more effective than KNO3 and NaNO3. The maximum of incinerating rate of briquette is improved from 0.38 to 0.6 g/ min and Fe2O3 and KClO3 can apparently reduce the release of organic gas during the incineration of briquette. But KClO3 can greatly reduce the release of sulphur. When the adding amount of CaCO3, K2CO3, KMnO4 and KClO3 is 16‰, 12‰, 18‰, 6‰ respectively in the process of briquette preparation, the sulphation efficiency reached the maximum of 95.3%, and there is still an extremely small amount of organic gas in flue gas. CaCO3, K2CO3, KMnO4 and KClO3 used in emission control of air pollutants and full combustion of briquette during incineration of oily sludge based-briquette, demonstrates high efficiency and low emission compared to other additives tested in this study.

Background Improving stem cell (SC) deformability using pre-treatment strategies, or isolating more deformable sub-populations, may prevent non-specific entrapment of injected cells, maintain circulating numbers and thus increase the likelihood of capture by microvessels in injured organs. However, nothing is currently known about the basic mechanical properties of SCs, particularly with regards their elastic characteristics. This study therefore aimed to determine the mechanical characteristics of haematopoietic stem cells (HSCs) and mesenchymal stem cells (MSCs) with comparisons made to neutrophils. Methods Micromanipulation and atomic force microscopy (AFM) were used to quantitate mechanical properties following large and small deformations respectively of neutrophils, MSCs and naive and stromal cell-derived factor-1α (SDF-1ɑ) or hydrogen peroxide (H2O2) pre-treated HSCs. Results Neutrophils and HSCs underwent rupture at ∼80% deformation. Nominal rupture stress (σR), nominal rupture tension (TR) and the Young's/elastic modulus at large deformations was significantly higher for neutrophils indicating they were stiffer and less deformable than HSCs. Surprisingly, MSCs did not rupture and were as deformable as HSCs despite their large size. Pre-treatment increased HSC deformability as indicated by lower rupture force, σR, TR and Young's modulus at large deformations. AFM demonstrated that pre-treatment increased the Young's modulus at smaller deformations indicating the HSC surface stiffened. This was accompanied by increased F-actin accumulation and its localisation in the cell cortex. Conclusion This is the first study to precisely demonstrate that mechanical distinctions exist amongst different therapeutic SCs with regards their deformability and rupture response to applied stress. This can potentially be utilized as label-free markers in microfluidic cell sorting systems to separate sub-populations of potentially more therapeutic SCs.

One-dimensional H2Ti3O7 nanowires (NWs) supported by Au, Ag, and Pd monometallic nanoparticles (NPs) and Au–Pd bimetallic NPs were prepared and used for photochemical benzyl alcohol oxidation. Tech...

The clay with high oil content form soil lumps, which is hard for microbes to repair. In this paper, the bioremediation + biostimulation was applied to improve the bioremediation effect of the soil with high oil content, that modified by local cow dung and sandy soil, the ecological toxicity of the soil after restoration was further analyzed. After 53 days of bioremediation, the degradation efficiency with respect to the total petroleum hydrocarbon (TPH) content reached 76.9% ± 2.2%; the soil bacterial content reached 4.9 × 107 CFU/g soil and the results were better than those in the natural attenuation M1group of experimental soils. The relative abundances of petroleum-degrading bacteria added to M5 remained high (Achromobacter 9.44%, Pseudomonas 31.06%, and Acinetobacter 14.11%), and the proportions of some other indigenous bacteria (Alcanivorax and Paenibacillus) also increased. The toxicity of the bioremediated soil was reduced by seed germination and earthworm survival experiments.

Engineering noncovalent interactions for assembling nonspherical proteins into supramolecular architectures with tunable morphologies and dynamics is challenging due to the structural heterogeneity and complexity of protein surfaces. Herein, we employed an anisotropic building block l-rhamnulose-1-phosphate aldolase (RhuA) to control supramolecular polymorphism in highly ordered protein assemblies by introducing histidine residues. Histidine-based π-π stacking interactions enabled thermodynamically controlled self-organization of RhuA to form three-dimensional (3D) nanoribbons and crystals. Self-assembly of different 3D crystal phases was kinetically modulated by the strong metal ion-histidine chelation, and double-helical protein superstructures were formed by engineering increased histidine interactions at the RhuA binding surface. Their structural properties and dynamics were determined via fluorescence microscopy, transmission electron microscopy, atomic force microscopy, and small-angle X-ray scattering. This work is aimed at expanding the toolbox for the programming of tunable, highly ordered, protein superstructures and increasing the understanding of the mechanisms of protein interfacial interactions.

With the continuous development of China's social and economic civilization, interaction design has more and more connections with our urban space construction. As a fusion of science, technology and art, interaction design has played an important role in promoting the development of various industries in public spaces. In interaction design, space is not an empty container for everything in the world, nor is it a scientifically abstract mechanical or geometric space. The purpose of this article is to explore and study the relationship between exhibits and space visitors through the spatial expression of interactive design. This paper studies the number of accounts for users of a city construction website to learn about interaction design knowledge, and investigates the customer satisfaction survey of a construction company using interaction design in the construction of urban public spaces, and the degree of execution of interaction design methods by a certain university’s technicians and scholars. Analyze and study the characteristics of interaction design and the application of spatial concepts in interaction design. Through an experimental investigation of existing interaction design, the results show that interaction design has become a concrete and practical way of creation, opening up a new perspective for traditional space design, improving the efficiency of interaction design information transmission, and making the design richer and more comprehensive. It is more interesting, logical and scientific, and aims to develop different design interaction ideas and apply them to the future urban public spaces.

A novel polymer/activated carbon composite was prepared in this study by one-step chemical activation of Sargassum horneri, followed by surface modification with chitosan, a widely abundant biopolymer. The prepared composite was used as adsorbent to remove one of the most toxic metal ions, Cr(VI), from aqueous solution. Surface characterization tests revealed the material to be predominantly mesoporous with the specific surface area of 293.4 m2·g−1 and the average pore diameter of 6.27 nm. Enhanced uptake capacity of Cr(VI) by the prepared composite was obtained due to the presence of more metal-binding functional (amino and hydroxyl) groups on its surface. Extremely fast adsorption rate of Cr(VI) was also achieved due to the porous structure of the prepared composite. This study has clearly shown that Sargassum horneri can be a potential alternative precursor for carbon-based adsorbents and the proper designed polymer/AC composites can be tailor-made adsorbents for heavy metal removal.

A large amount of livestock manure is produced every year around the world, which requires harmless utilization to reduce environmental pollution and produce energy. As a promising and pollution-free technology in recent years, Supercritical water gasification (SCWG) can utilize pig manure with high moisture to produce hydrogen. In this paper, a novel process modeling an auto-thermal SCWG polygeneration system of pig manure was established with thermodynamic analysis, coupled with in-situ hydrogen separation and waste heat recovery method. Simultaneously, the environmental significance was analyzed through Life cycle assessment (LCA), and the GWP was 1.73 kgCO2-eq/kgH2 under optimal conditions with CCS. The results showed that the system with in-situ hydrogen separation would produce more H2 to improve energy efficiency. Adding a waste heat recovery unit could reduce the exergy loss of 89.14% of the cooling unit, which had the largest exergy loss in the system. In this study, there were 5081Nm3/h of H2 and 16377 kW of hot steam produced when the SCWG system was auto-thermal (620 ℃, 25 MPa, 650 t/d dry manure and 10 wt% reactor concentration), where the energy efficiency of the system could reach 79.85% that had a 3.6–35.64% increase to the previous SCWG systems. In addition, the optimal operating parameters of this polygeneration system were obtained, which the exergy efficiency could reach 54.25%. A lower complete gasification temperature and a larger in-situ H2 separation ratio were conducive to achieving higher H2 yield when the optimal ratio of preheated water to dry material was 8.

Au/TiO2 catalysts were synthesized through Cinnamomum camphora leaf extract. The obtained catalysts were characterized through TEM, XRD, DRUV–vis and were used for CO oxidation. The influence of various parameters (Au loading, biomass, calcination atmosphere, and support crystal form) on the catalytic performance in CO oxidation was studied in detail. The experimental result revealed that under the conditions of 1.0 wt % Au loading, calcination atmosphere of air, TiO2 with mixed crystal of rutile and anatase, the Au/TiO2 catalyst exhibited optimum catalyitc performance, which remained its 90% CO conversion after 150 h.

A tremendous amount of livestock manure is produced every day, and its harmless and efficient utilization is of profound significance for environmental protection and alternative energy supply. Supercritical water gasification (SCWG) is an efficient and clean technology for high-moisture waste utilization. However, very few researchers have studied the SCWG of manure from system-level modeling. Here, an original or reference pig manure SCWG plant is established for power generation based on previous studies. Detailed exergy analysis shows that the most significant part of exergy destruction occurs in the recuperation process, accounting for 38.05% of total exergy loss. Then, several optimizations were made in a modified system, focusing on a better layout of heat exchangers and critical streams. The modified system had a substantial gain of 23% in overall exergy efficiency and produced 14.12 MW power at an electric efficiency of 27.7%, much higher than 2.08 MW and 5.07% in the original system. Sensitivity analysis further proves that increasing feedstock concentration, preheating temperature, and turbine parameters while decreasing the water-slurry ratio can increase total system efficiency. The efficient multi-stage heat exchanger network and steam turbine in this paper are preferred for SCWG of pig manure, considering system capacity, complexity, and zero-carbon emission.

A crucial step in enabling adoptive T cell therapy is the isolation of antigen (Ag)-specific CD8+ T lymphocytes. Mechanical changes that accompany CD8+ T lymphocyte activation and migration from circulating blood across endothelial cells into target tissue, may be used as parameters for microfluidic sorting of activated CD8+ T cells. CD8+ T cells were activated in vitro using anti-CD3 for a total of 4 days, and samples of cells were mechanically tested on day 0 prior to activation and on day 2 and 4 post-activation using a micromanipulation technique. The diameter of activated CD8+ T cells was significantly larger than resting cells suggesting that activation was accompanied by an increase in cell volume. While the Young's modulus value as determined by the force versus displacement data up to a nominal deformation of 10% decreased after activation, this may be due to the activation causing a weakening of the cell membrane and cytoskeleton. However, nominal rupture tension determined by compressing single cells to large deformations until rupture, decreased from day 0 to day 2, and then recovered on day 4 post-activation. This may be related to the mechanical properties of the cell nucleus. These novel data show unique biomechanical changes of activated CD8+ T cells which may be further exploited for the development of new microfluidic cell separation systems.

Unmanned vehicles will play an extremely important role in the future development of intelligent transportation system. The research background and significance of unmanned vehicles were introduced and the research status of decision-making of unmanned vehicles at home and abroad was summarized in this paper. And the rule-based behavior decision-making methods and machine learning-based behavior decision-making methods were summarized. To solve the problem of unmanned vehicles crossing at the intersection of city, considering the safety and efficiency of the crossing process, the method of finding the optimal traversing strategy based on the reinforcement learning algorithm was proposed. Finally, the effectiveness of the algorithm was verified by the intersection crossing case. The results show that compared with Q-Learning algorithm, the NQL algorithm proposed in this paper needs fewer training samples and shorter training time when it converges.

Remediating and controlling PAHs (Polyaromatic Hydrocarbons) contamination in the environment is essential all over the world. Nano-TiO2 immobilized on large surface area adsorbent is a kind of emerging endeavor to enhance the photo-catalysis performance. In this paper, activated carbon samples (ACs) were synthesized by using a kind of subtropical macroalgae, i.e., Sargassum Horneri (S.H.) as raw material. ACs activated by FeCl3, ZnCl2, a composite activators mixture of FeCl3 and ZnCl2 (CA) were selected to immobilize nano-TiO2 in aquatic environment, and naphthalene degradation performance of these materials was systematically assessed. The results showed that ACs could provide more activated space for naphthalene photocatalytic reaction, in which Zn2+ helped to hold relative high specific surface area, Fe3+ helped to extend the valid light responsive wavelength, and CA could take advantage of both metal ions, with the largest whole volume and surface functional groups. The highest naphthalene degradation efficiency of TiO2/AC-CA under simulated sunlight could arrive to 77.5%, while those of TiO2/AC-FeCl3 and TiO2/AC-ZnCl2 were 65.0%, 54.5%, respectively. Meanwhile, the pH-resistance and reusing capability of TiO2/AC-CA are better than those of other TiO2/ACs. The results helped to clarify the synergistic mechanism of AC and TiO2 in photo-catalysis, especially the metal ions’ role in combining the two materials, and showed the industrial potential of S.H. in PAHs contamination.

The Au/TS-1 catalysts with different Au nanoparticles (NPs) sizes ranging from 3.1 to 8.4 nm but the same Au loading of 0.5 wt% were prepared by Cinnamomum camphora (CC) extract, and were used for propylene epoxidation. The results showed that the interaction between Au and TS-1 support surface is important for propylene epoxidation and much smaller Au NPs (

Supported Ag catalyst for ethylene epoxidation was prepared by an impregnation–bioreduction process with Cinnamomum camphora (CC) extract. Influence of bioreduction temperature, concentration of CC extract, silver loading amount, calcination temperature as well as Cs promoter on catalytic performance were thoroughly investigated and the catalysts were characterized. The results showed that the catalyst prepared from bioreduction process exhibited excellent performance for the ethylene epoxidation with O2. Proper amount of Cs addition could effectively improve the catalytic performance of the catalyst. The optimal catalyst 15Ag/α-Al2O3-150Cs gave the EO concentrations of 1.70%, EO selectivity of 87.46% and EO STY of 223.07 g h−1 L−1cat at 200 °C, showing high catalytic stability with no significant decrease in the activity and the selectivity during 50 h.

TiO2(B) is typical crystal structure for TiO2, besides anatase, rutile and brookite. In this work, one-dimensional TiO2(B) modified by Pd were prepared. The obtained Pd/TiO2(B) was used for photo-thermocatalytic benzyl alcohol oxidation. Well-matched heterostructure contact boundary between (111) planes of Pd nanoparticles and (003) planes of TiO2(B) was formed, which might facilitate interfacial photo-generated electrons transfer. The Pd/TiO2(B) catalyst exhibited enhanced the photo-thermocatalytic activity, attributed tothe synergistic effect of Pd, TiO2(B) and their well-matched heterojunction, and also the synergism between the thermocatalysis and photocatalysis.

This paper presents a Lexicon-Corpus-based Unsupervised (LCU) Chinese word segmentation approach to improve the Chinese word segmentation result. Specifically, it combines advantages of lexicon-based approach and Corpus-based approach to identify out-of-vocabulary (OOV) words and guarantee segmentation consistency of the actual words in texts as well. In addition, a Forward Maximum Fixed-count Segmentation (FMFS) algorithm is developed to identify phrases in texts at first. Detailed rules and experiment results of LCU are presented, too. Compared with lexicon-based approach or corpus-based approach, LCU approach makes a great improvement in Chinese word segmentation, especially for identifying n-char words. And also, two evaluation indexes are proposed to describe the effectiveness in extracting phrases, one is segmentation rate (S), and the other is segmentation consistency degree (D).

Microorganism-mediated, hexadecyltrimethylammonium chloride (CTAC)-directed (MCD) method was employed in this work to synthesize Pd nanoflowers (PdNFs). Proper Pichia pastoris cells (PPCs) dosage, ascorbic acid (AA), Pd(NO 3 ) 2 and CTAC concentrations were essential for the growth of the PdNFs. The size of the as-synthesized PdNFs could be tuned by adjusting the amount of Pd(NO 3 ) 2 solution and dosage of PPCs used. Characterization techniques such as X-ray diffraction, transmission electron microscopy, and X-ray photoelectron spectroscopy were used to verify the nature of the PdNFs. Finally the PdNF/PPC nanocomposites were immobilized onto TiO 2 supports to obtain bio-PdNF/TiO 2 catalysts which showed excellent catalytic activity for CO oxidation, obtaining 100% conversion at 100 °C and remaining stable over a period of 52 h of reaction time.

BACKGROUND Au valence for Au catalysts has been considered a vital parameter for catalytic activity towards CO oxidation. However, there is no effective method to prepare precise Au0/Auδ+ molar ratios with the same Au nanoparticles (NPs) sizes. RESULTS A series of Au/TiO2 catalysts with tuneable Au0/Auδ+ molar ratios were prepared by the combination of a biosynthesis method and a deposition–precipitation (DP) method, and characterized by XPS, TEM, DRUV-Vis techniques. First, biosynthesized metallic Au NPs were immobilized onto TiO2 supports to obtain Au/TiO2 catalysts with different Au loadings but with the same sized Au NPs. And then positively ionized Au species were supported onto the above Au/TiO2 catalysts by a DP method. The metallic Au and positively ionized Au species could be totally supported on the support. Therefore, the Au0/Auδ+ molar ratios could be controlled exactly. Compared with Au/TiO2 catalysts with metallic and positively ionized Au species alone, the catalyst Au/TiO2-1:1 showed the best initial catalytic activity, suggesting enhanced catalytic performance due to the coexistence of Au0 and Auδ+. CONCLUSION This study verifies that Au/TiO2 catalysts with accurate Au0/Auδ+ molar ratios can be prepared by a combination of biosynthesis and a DP method. © 2015 Society of Chemical Industry

In this paper, we report a microwave-assisted biosynthesis method with Cinnamomum camphora (CC) leaf extract for the green and rapid synthesis of Ag nanoparticles (NPs). The as-produced Ag nanoparticles were immobilized onto CeO 2 as supported Ag/CeO 2 catalyst, which proved to be efficient for carbon monoxide (CO) oxidation. Active components in the plant extract were identified by FTIR analysis and later on validated through simulated experiments. The results revealed that polyphenols and proteins were the reducing and protecting agents, respectively. The optimum preparation conditions for the catalyst were irradiation time of 140 s, Ag loadings of 5 wt.%, CC extract concentration of 25 g L −1 and sintering temperature of 300 °C. Since biomolecules adsorbed over the surface of catalyst was detrimental to its catalytic activity, calcination to remove the biomolecules was critical to the enhanced activity. Considering the trade-off between particle size and biomass removal extent, the optimum calcination temperature was determined to be 300 °C.

Pd/γ-Al2O3 catalysts efficient for the liquid-phase hydrogenation of 2-ethyl-9,10-anthraquinone were prepared via an adsorption–reduction method using Cacumen Platycladi extract as both reductive and protective agent. The catalysts were characterized by N2 physisorption, X-ray diffraction, transmission electron microscopy and X-ray photoelectron spectroscopy. The results showed that Pd nanoparticles (NPs) measuring

A series of Au/TiO2 catalysts for CO oxidation with same Au loading but different Au nanoparticles (NPs) sizes were prepared by varying the calcination temperatures and biomass concentration via a biosynthetic approach. The resulting catalysts were characterized by DRUV–vis, TEM, and TG techniques. The experimental results showed that the activity of the gold catalysts for CO oxidation was very sensitive to the particle size. Among the tested catalysts, the one with mean size of 3.8 nm was the most active. As determined by TEM, the contact boundary between the Au NPs and the TiO2 support was related to the size of the Au NPs. For the most active catalyst, hemispherical Au NPs (3.8 ± 0.6 nm) had the best contact boundary with the TiO2 support, yielding the longest perimeter interface, suggesting that the contact boundary was the most critical factor for the CO oxidation. The in-situ FTIR study of CO adsorption on the catalysts showed that CO was not adsorbed on the Au surface. This might be due to the modi...

national Nature Science Foundation of China (NSFC) [21036004]; State Key Laboratory of Advanced Technologies for Comprehensive Utilization of Platinum Metals [SKL-SPM-201210]

Herein, we reported the green synthesis of Ag–Pd alloy nanoparticles (NPs) using the aqueous extract of the Cacumen platycladi leaves as well as their application as catalyst for hydrogenation of 1,3-butadiene. The biosynthetic NPs were characterized to confirm the nature of alloy by UV–vis spectroscopy, X-ray diffraction (XRD), transmission electron microscopy (TEM), and energy dispersive X-ray spectroscopy (EDX). The possible functional groups responsible for the reduction and protection of NPs were identified through Fourier transform infrared spectroscopy (FTIR). The results revealed that biomolecules like saccharides, polyphenols, or carbonyl compounds were related to the reduction process, and the (NH)C═O groups were responsible for the stabilization of the NPs. Furthermore, the as-formed Ag–Pd bimetallic-supported catalysts especially Ag1Pd3/γ-Al2O3 was found to possess excellent catalytic performance toward hydrogenation of 1,3-butadiene. A butene yield of 84.9% was obtained, which was remarkably ...

Au/TS-1 catalysts prepared by an eco-friendly and economical bioreduction method were used for the liquid phase epoxidation of styrene to styrene oxide (SO) using aqueous hydrogen peroxide (H2O2) as oxidant. The catalysts were characterized by a variety of techniques including FT-IR, DRUV–Vis, UV–Vis, N2 physisorption, XRD, XPS, TG–DTG and TEM. The influence of various parameters (Au loading, calcination, solvents, oxidants, reaction temperature, reaction time and catalyst amount) on the catalytic performance was systematically investigated. The results showed that both the conversion of styrene and selectivity to SO were improved and enhanced when catalyzed by biosynthesized gold nanoparticles (GNPs) supported on TS-1. However, decomposing the Cacumen Platycladi (CP) biomass properly through calcinations can enhance the catalytic performance though it acted as reductant and protective agents during the catalysts preparation. Besides, the optimum catalytic activity and stability of bioreduction Au/TS-1 catalysts were obtained under operational conditions of Au loading of 1.0 wt.%, CP extract (10 g L−1) as reductant, calcined at 723 K for 2 h, reaction time of 10 h, reaction temperature of 333 K, catalyst amount of 500 mg, aqueous H2O2 (30 wt.%) as oxidant and N,N-dimethylformamide as solvent. Under the optimal condition, styrene conversion of 92.7% and SO selectivity of 90.4% was achieved, which were comparable or even superior to those reported in the literatures. The catalyst was reused five times, without significant decrease in both the styrene conversion and SO selectivity.