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To establish an ideal microenvironment for regenerating maxillofacial defects, recent research interests have concentrated on developing scaffolds with intricate configurations and manipulating the stiffness of extracellular matrix toward osteogenesis. Herein, we propose to infuse a degradable RGD-functionalized alginate matrix (RAM) with osteoid-like stiffness, as an artificial extracellular matrix, to a rigid 3D-printed hydroxyapatite scaffold for maxillofacial regeneration. The 3D-printed hydroxyapatite scaffold was produced by microextrusion technology and showed good dimensional stability with consistent microporous detail. RAM was crosslinked by calcium sulfate to manipulate the stiffness, and its degradation was accelerated by partial oxidation using sodium periodate. The results revealed that viability of bone marrow stem cells was significantly improved on the RAM and was promoted on the oxidized RAM. In addition, the migration and osteogenic differentiation of bone marrow stem cells were promoted on the RAM with osteoid-like stiffness, specifically on the oxidized RAM. The in vivo evidence revealed that nonoxidized RAM with osteoid-like stiffness upregulated osteogenic genes but prevented ingrowth of newly formed bone, leading to limited regeneration. Oxidized RAM with osteoid-like stiffness facilitated collagen synthesis, angiogenesis, and osteogenesis and induced robust bone formation, thereby significantly promoting maxillofacial regeneration. Overall, this study supported that in the stabilized microenvironment, oxidized RAM with osteoid-like stiffness offered requisite mechanical cues for osteogenesis and an appropriate degradation profile to facilitate bone formation. Combining the 3D-printed hydroxyapatite scaffold and oxidized RAM with osteoid-like stiffness may be an advantageous approach for maxillofacial regeneration.

Background/Purpose Supracrestal ridge augmentation (SRA) is a major challenge for clinicians. This study investigated the efficacy of a 3D-printed (3DP) hydroxyapatite/poly(lactic-co-glycolic acid) (HA/PLGA) scaffold as a potential biologic for SRA. Methods Scaffolds that were 5 mm in diameter and 2.5-mm thick with a 1.2-mm diameter through-and-through central hole composed of 90% HA and 10% PLGA were printed using an extrusion-based bioprinter. The HA/PLGA scaffold was fixed with a 1.2-mm titanium mini-implant on the buccal surface of rat mandible (Ti-HPS), and the outcome of SRA were compared with sites treated with a titanium mini-implant alone (control) and a titanium mini-implant covered with deproteinized bovine bone-derived matrix (Ti-DBBM) at 4 and 8 weeks by microcomputed tomography (micro-CT), back-scattered SEM, and histology assessments. Results The HA/PLGA scaffolds were 2.486 ± 0.082 mm thick with an outer diameter of 4.543 ± 0.057 mm and an inner diameter of 1.089 ± 0.045 mm, and the pore dimensions were 0.48–0.52 mm. There was significantly more mineralized tissue in the Ti-DBBM and Ti-HPS groups than in the control group at both time points. Newly formed bone (NB) was well-integrated with the DBBM and HA/PLGA scaffolds. The framework of the 3DP-HA/PLGA scaffold remained in place, and NB-implant contact (NBIC) was advanced to the middle level in the Ti-HPS group until 8 weeks, whereas dispersion of DBBM with a lower level NBIC was noted in the Ti-DBBM group at both time points. Conclusion The 3DP HA/PLGA scaffold maintains supracrestal space and demonstrates osteoconductivity to facilitate SRA.

This study aimed to evaluated the potential of core-shell poly(D, l -lactide-co-glycolide)-chitosan (PLGA-chitosan) nanospheres encapsulating simvastatin (SIM) and doxycycline (DOX) for promoting periodontal and large-sized osseous defects. SIM, and/or DOX were encapsulated in PLGA-chitosan nanospheres using double emulsion technique and were delivered to sites of experimental periodontitis and large-sized mandibular osseous defects of rats for 1–4 weeks. The resultant nanospheres were ~ 200 nm diameter with distinct core-shell structure and released SIM and DOX sustainably for 28 days. DOX and SIM-DOX nanospheres significantly inhibited P. gingivalis and S. sanguinis. In experimental periodontitis sites, SIM-DOX nanospheres significantly down-regulated IL-1b and MMP-8 and significantly reduced bone loss. In mandibular osseous defects, VEGF was up-regulated, and osteogenesis was significantly augmented with SIM nanospheres treatment. In conclusion, core-shell PLGA-chitosan nanospheres released SIM and DOX sustainably. SIM-DOX and SIM nanospheres could be considered to promote the repair of infected periodontal sites and non-infected osseous defects respectively.

Defensive behavior, a group of responses that evolved due to threatening stimuli, is crucial for animal survival in the natural environment. For defensive measures to be timely and successful, a high arousal state and immediate sleep-to-wakefulness transition are required. Recently, the glutamatergic basal forebrain (BF) has been implicated in sleep-wake regulation; however, the associated physiological functions and underlying neural circuits remain unknown. Here, using in vivo fiber photometry, we found that BF glutamatergic neuron is activated by various threatening stimuli, including predator odor, looming threat, sound, and tail suspension. Optogenetic activation of BF glutamatergic neurons induced a series of context-dependent defensive behaviors in mice, including escape, fleeing, avoidance, and hiding. Similar to the effects of activated BF glutamatergic cell body, photoactivation of BF glutamatergic terminals in the ventral tegmental area (VTA) strongly drove defensive behaviors in mice. Using synchronous electroencephalogram (EEG)/electromyogram (EMG) recording, we showed that photoactivation of the glutamatergic BF-VTA pathway produced an immediate transition from sleep to wakefulness and significantly increased wakefulness. Collectively, our results clearly demonstrated that the glutamatergic BF is a key neural substrate involved in wakefulness and defensive behaviors, and encodes these behaviors through glutamatergic BF-VTA pathway. Overexcitation of the glutamatergic BF-VTA pathway may be implicated in clinical psychiatric diseases characterized by exaggerated defensive responses, such as autism spectrum disorders.

Background Three-dimensional (3D) printing has become an available technology to fabricate customized tissue engineering scaffolds with delicate architecture. This exploratory study aimed to evaluate the potential of a 3D-printed hydroxyapatite-based scaffold as a biomaterial for obtaining guided bone regeneration (GBR) in vivo. Methods Scaffolds composed of 90% hydroxyapatite and 10% poly(lactic-co-glycolic acid) were printed using a microextrusion process to fit 4 mm diameter and 0.5 mm thick through-and-through osseous defects on the mandibular ramus of rats, with unfilled defects serving as controls. Specimens were analyzed for regeneration-associated gene expression on day 7, and micro-computed tomography (micro-CT) and histology assessments were carried out on day 28. Results The scaffolds were 3.56 ± 0.43 mm (x-axis) and 4.02 ± 0.44 mm (y-axis) in diameter and 0.542 ± 0.035 mm thick (z-axis), with a mean pore size of 0.420 ± 0.028 × 0.328 ± 0.005 mm2 . Most scaffolds fit the defects well. Type I collagen, VEGF, and Cbfa1 were upregulated in the scaffold-treated defects by day 7. By day 28, de novo osteogenesis and scaffold-tissue integration were evident in the scaffold-treated defects, and entire mineralized tissue, as well as newly formed bone, was significantly promoted, as seen in the micro-CT and histologic analyses. Conclusion The 3D-printed hydroxyapatite-based scaffold showed acceptable dimensional stability and demonstrated favorable osteoregenerative capability that fulfilled the need for GBR.

With the development of CUDA architecture and GPU technologies, parallel rendering technologys have been developed rapidly. There are already some parallel rendering frameworks, such as Chromium, MPK, VR Juggler, etc., but these systems have obvious flaws.In this paper,GGPRF: a GPU-Based Generic Parallel Rendering Framework is proposed. The framework contains three roles, Master, Server, and Slave, which are responsible for rendering task drivers, cluster management, and rendering. Server manages the entire parallel rendering system's organizational structure through the NTTree (Network Topological Tree) data structure. GGPRFhas improved the shortcomings of the existing universal parallel rendering framework, which has the advantages of universal, extensibility and ease of use. In this paper, the design of the frame is described in detail and the experiment is tested.

In the present work, a series of α-hydroxyimine palladium complexes with bulky substituents (i.e., {[Ar-N═C(R)–C(R)2–OH]PdCl2} (C1, R = Me, Ar = 2-diphenylmethyl-4,6-dimethylphenyl; C2, R = Me, Ar = 2,6-bis(diphenylmethyl)-4-methylphenyl; C3, R = Me, Ar = 2,6-bis(diphenylmethyl)-4-methyoxylphenyl; C4, R = Me, Ar = 2,6-bis(diphenylmethyl)-4-chlorophenyl; C5, R = Ph, Ar = 2,6-dimethylphenyl; C6, R = Ph, Ar = 2,6-diisopropylphenyl)) were synthesized and characterized. The structures of palladium complexes C1 and C2 were determined by X-ray diffraction. These bidentate N,O-palladium complexes were applied for direct arylation under aerobic conditions. The effects of the reaction conditions and ligand substitution on the catalytic activity were evaluated. Upon a low palladium loading of 0.5 mol %, the bulky palladium complex C6 was successfully used to catalyze the cross-coupling of a variety of five-membered heteroarenes and their benzo-condensed derivatives with (hetero)aryl bromides. The mechanistic investi...

Performances of Ag-SnO2 electrical contact materials can be strongly affected by the microstructure. In this work, Ag-SnO2 composite powders were synthesized by chemical reductive precipitation method. During the precipitation process, Ag particle was deposited onto the surface of SnO2 particle with the assistance of citric acid. The microstructure and properties were analyzed for the prepared Ag-SnO2 electrical contact materials. Our research reveals that the particle size of SnO2 has significant influence on the morphology of the Ag-SnO2 composite powders, and therefore on the microstructure and physical properties of the electrical contact materials. With the decrease of particle size of SnO2, hardness of the Ag-SnO2 electrical contact materials increases, while electrical conductivity decreases.

We present a novel approach called Global Color Composition (GCC) to improve the visual effect of large image show on curved screen multi-projector display system. Instead of traditional approach only blend overlapped area, our algorithm utilize the global gradient-domain information to get better effect, and as an optimizing of the algorithm to reduced time and memory, we utilize the patches border pixels to construct the passion equation. The solver of this passion equation is result image we desired, which can be solving on parallel GPU threads. Experiment results are given to illustrate the effect of our approach.

An electrochemiluminescence (ECL) approach for methamphetamine determination was developed based on a glassy carbon electrode modifi ed with a Ru(bpy)3 2+ -doped silica nanoparticles/Nafi on composite fi lm. The monodispersed nanoparticles, which were about 50 nm in size, were synthesized using the water-in-oil microemulsion method. The ECL results revealed that Ru(bpy)3 2+ doped in silica nanoparticles retained its original photo- and electrochemical properties. The ECL in- tensity was found to be proportional to methamphetamine concentration over the range from 1.0 ¥ 10 -7 to 1.0 ¥ 10 -5 mol L -1 , and the detection limit was found to be 2.6 ¥ 10 -8 mol L -1 . The proposed ECL approach was used to analyze the methamphet- amine content in drugs. Copyright © 2009 John Wiley & Sons, Ltd. 2+ -doped silica; methamphetamine

A novel direct readout colorimetric optical glucose sensor strip was constructed based on a three-layer film, including a green-emitted CdTe/CdS quantum dots (QDs) layer as a stable color background, a red-fluorescent platinum-porphyrin oxygen-sensing layer and a glucose oxidase layer. The sensor achieved high resolution (up to 0.2 mmol L(-1)) glucose determination with a detection range from 0 to 3.0 mmol L(-1). A "glucose ruler" which acts as a glucose standard colorimetric card was obtained. Glucose concentration could easily be directly readout using the "glucose ruler", which made the glucose determination rapid, convenient and easy. The effects of pH, salinity and temperature were systematically investigated. The prepared sensor was finally applied for glucose sample analysis, compared with the "glucose ruler", accurate results could be directly readout.

A colorimetric electrochemiluminescence (ECL) sensor was fabricated for the first time, based on a dual-color system including a strong red Ru(bpy)(3)(2+) ECL and a green reference light from a light emitting diode. Traditional ECL intensity information can be easily transformed into a color variation with this sensor, and the color variation can be directly monitored using the naked eye or a commercial CCD camera. The sensor has been successfully used to determine the concentration of tripropylamine, proline (enhancing system), and dopamine (quenching system). The results indicated that the color variation obtained corresponded to the concentration of target analytes. This sensor has potential application in rapid and semiquantitative ECL analysis.

A simple, novel electrochemiluminescence (ECL) method for the detection of dichlorvos pesticide (DDVP) with high sensitivity was discovered. Detection was carried out in a static ECL system, in which a glassy carbon electrode was selected as the working electrode. ECL parameters, including the concentrations of cetyrltrimethylammonium bromide and luminol, the solution pH, and the scan rate of the applied potential, were optimized. Under these optimal conditions, the linear response of ECL-emission versus DDVP concentration was valid in the range 5-8000 ng/L (r(2)=0.9982) with a relative standard deviation of 4.3% at 2000 ng/L (n=10), yielding a detection limit (S/N=3) of 0.42 ng/L. The ECL emission was caused by a radical reaction process, in which the dissolved oxygen in the luminol solution reacted with the DDVP and generated free radicals. The free radicals reacted with the luminol anion and yielded the luminol radical. The approach presented was successfully applied to the determination of DDVP residues in vegetable samples.

A ceramic/carbon composite was developed and applied as a novel coating for solid-phase microextraction (SPME). The ceramic/carbon coating exhibited several good properties for SPME, such as high extraction quantities and enhanced thermal and organic solvent stability. Under scanning electron microscopy (SEM), the tightly attached coating layer on stainless steel wire revealed excellent mechanical characteristics. Single fiber and fiber-to-fiber reproducibility were less than 6.9 and 9.5%, respectively. The effects of extraction and desorption parameters such as extraction time, stirring rate, ionic strength, and desorption temperature and desorption time on the extraction/desorption efficiency were investigated and optimized. Coupled to gas chromatography with a flame thermionic detector, the optimized SPME method was applied to the analysis of organophosphorus pesticides (OPPs) in aqueous samples. The calibration curves were linear from 0.05 to 200 ng mL−1 for fenchlorphos, pirimiphos-methyl, chlorpyrifos, ethion and from 0.2 to 200 ng mL−1 for quinalphos, and the limits of detection were between 5.2 and 34.6 ng L−1. The recovery of the OPPs spiked in real water samples at 5 ng mL−1 ranged from 86.2 to 103.4% and the relative standard deviations were less than 8.5%.

In this study, the initial transformation of gold seed on indium tin oxide (ITO) surfaces was investigated. Gold nanoparticles (AuNPs) grew on ITO surfaces using a seed-mediated method. The reduction rate of gold(I) salt and the shapes of AuNPs were affected by the concentration of cetyltrimethylammonium bromide (CTAB). Gold nanorods (AuNRs) appeared when the CTAB concentration was above 75 mM, and the shapes agreed with the dispersing state of CTAB micelles in solution. CTAB was replaced by cetyltrimethylammonium chloride (CTAC) in the growth procedure. Only small gold nanospheres (AuNSs) appeared when the CTAC concentration was increased. This result agreed with the dispersing state of CTAC micelles in solution and implied that gold salts were not free in either CTAB or CTAC solution. A red shift of 14 nm in the UV–vis spectra of AuBr4− was found in the presence of CTAB, and furthermore, AuBr2− became stable. This indicated that the gold salt strongly bound to cetyltrimethylammonium ion (CTA+) and was c...

An effective electrochemiluminescence (ECL) sensor was developed by combining bis(2,2′-bipyridine)-5-amino-1,10-phenanthroline ruthenium(II) [Ru(bpy) 2 (5-NH 2 -1,10-phen) 2+ ] with functionalized carbon nanotubes (FCNTs) coated on a glassy carbon electrode. Treatment with a nitric acid and sulfuric acid mixture (1:3, v/v) led to multiwall carbon nanotubes terminated with carboxylic acid groups. These were characterized using Fourier transform infrared absorption spectroscopy (FTIR) measurement and a transmission electron microscope (TEM). N -hydroxy-succinimide and 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide hydrochloride were applied to activate the carboxyl groups and, according to the observation from FTIR and energy-dispersed spectroscopy (EDS) measurements, they catalyzed the formation of an amide bond between the FCNTs and Ru(bpy) 2 (5-NH 2 -1,10-phen) 2+ , resulting in a covalent bond. The FCNTs could provide a good immobilization matrix on the electrode by means of a hydrophobic interaction. In addition, because the FCNTs on the electrode surface were open structures with a large surface area and excellent conductivity, the modified electrode exhibited good electrochemical activity and ECL response. The ECL detection limit (S/N) for tripropylamine using this modified electrode was 8.8 × 10 −7 mol L −1 with a linear range from 1.0 × 10 −6 to 2.0 × 10 −3 mol L −1 ( R 2 = 0.9969). The ECL sensor presented good characteristics in terms of stability and reproducibility.

In this paper, a novel electrochemiluminescence (ECL) sensor was constructed to determine herring sperm (HS) double-stranded (ds) DNA. Tetramethoxysilane and dimethyldimethoxysilane were selected as co-precursors to form an organically modified silicate (ORMOSIL) film for the immobilization of multiwall carbon nanotubes (MWNTs) wrapped by poly(p-styrenesulfonate) (PSS), and then Tris(2,2'-bipyridyl)ruthenium(II) (Ru(bpy)3(2+)) was successfully immobilized on a glassy carbon electrode via ion-association. PSS was employed to increase the conductivity of the ORMOSIL film and disperse the cut MWNTs, which were cut and shortened in a mixture of concentrated sulfuric and nitric acids, in the film. It was found that MWNTs could adsorb Ru(bpy)3(2+) and acted as conducting pathways to connect Ru(bpy)3(2+) sites to the electrode. MWNTs also played a key role as materials for the mechanical and thermal properties. The ECL performance of this modified electrode was evaluated in a flow injection analysis (FIA) system, and the detection limit (S/N=3) for HS ds-DNA was 2.0x10(-7) g mL(-1) with a linear range from 1.34x10(-6) to 6.67x10(-4) gm L(-1) (R2=0.9876). In addition, the ECL sensor presented excellent characteristics in terms of stability, reproducibility and application life.

In order to use a water soluble organic electrochemiluminescence (ECL) reagent in an aqueous medium, a simple one-pot method was developed to synthesize 9,10-diphenylanthracene (9,10-DPA) doped polystyrene beads based on dispersion polymerization. The bead size was around 3 μm and they were well dispersed. Fluorescence experiments showed that the polystyrene beads were successfully doped in 9,10-DPA. The 9,10-DPA doped beads were then used in ECL studies, and they retained their ECL activity well. The results imply that polystyrene beads could be a suitable platform leading to the application of hydrophobic ECL reagents in aqueous media.

In this paper we report on the development of a down-exhaust cyclone separator suitable for use as a primary device for gas−particle separation in circulating fluidized-bed (CFB) boilers. It consists of a cylindrical shell which is joined by an inclined cone, a guide body, and a downward exhaust pipe. The principle of solids separation is similar to that in reverse flow cyclones, except that in this separator the gas leaves the separator axially at the bottom. It has been shown that this separator is capable of achieving a separation efficiency of around 99% in handling high solids loadings such as those in CFB boilers, at a pressure drop of around 400 Pa. A model based on the mechanism of radial solids mixing is proposed, which assumes that the slip between gas and particles in the tangential direction is negligible and that the particles are well-dispersed. This model enables prediction of grade separation efficiency, total separation efficiency, and cut diameter. It may be used in conjunction with a pr...

Background The objective of this study was to evaluate the effect of bone marrow mesenchymal stem cells (BMSCs) on the apoptosis of granulosa cells (GCs) in rats. BMSCs and GCs were isolated from rats. GCs were separated into one of the following three groups: an untreated control group (control), a cisplatin (5 mg/L) treatment group (cisplatin), and group co-cultured with BMSCs and treated with cisplatin (BMSC). GC apoptosis was analyzed by annexin V staining and real-time PCR analysis for apoptosis-related genes. The effect of BMSCs was also determined in 9 to 10 month-old perimenopausal rats that were separated into the following groups: saline control, BMSC transplantation (1–2 × 106 cells), and estrogen treatment (0.158 mg/kg/d) groups. A young group consisting of 3 to 4 month-old rats that were treated with saline was also evaluated as a control. After 1 and 3 months, GC apoptosis was evaluated by TUNEL analysis. Results Cisplatin increased GC apoptosis from 0.59% to 13.04% in the control and cisplatin treatment groups, respectively, which was significantly reduced upon co-culture with BMSCs to 4.84%. Cisplatin treatment increased p21 and bax and decreased c-myc mRNA expression, which was reversed upon co-culture with BMSCs. As compared to young rats, increased apoptosis was observed in the perimenopausal rats (P P = 0.007). Conclusions BMSC therapy may protect against GC apoptosis induced by cisplatin and perimenopause. Further studies are necessary to evaluate therapeutic efficacy of BMSCs.

Experiments were carried out in a pilot-scale circulating fluidized bed (CFB) coal combustor to investigate the mechanism of N,O formation, nitrogen oxides (including NO, and N,O) emission and the effect of temperature, excess air ratio, recirculation ratio, etc. The concentrations of nitrous oxide and nitric oxide were measured along the height of the CFB furnace. N,O concentration increased with height, and in the exit of the combustor N,O reached the highest level. NO,, however, decreased with height, showing the inverse trend compared with N,O. The N,O emission decreased sharply with the rise of temperature at the bottom of the combustor; at the same time, the NO, concentration increased.

This paper describes an experimental study on N2O and NOx emission from char combustion. Experiments have been carried out in a fixed bed reactor in the temperature range of 973−1323 K. Oxygen concentrations for combustion, temperature, and char type have been found to have strong effects on both N2O and NOx emissions. With an increasing temperature, N2O reaches a peak at 1073 K and then decreases with temperature. At the same time NOx remains nearly the same. When oxygen concentration increases, the concentration of N2O increases and NOx first increases and then decreases. The char with higher nitrogen content emits more N2O, indicating that nitrogen oxides come from char-N. When NO is included in the inlet gases, much more N2O is produced from char combustion. This suggests that the reaction of NO + O2 + char is the main pathway for N2O formation. Another pathway, i.e., the homogeneous oxidation of HCN from the gasfication of char, seems to be important as well.

Tris(4,7-diphenyl-1,10-phenanthroline)-ruthenium(II) (Rudpp) doped oxygen-resisting nanobeads were synthesized and applied in order to study the effects of oxygen on electrochemiluminescence.

In this paper, an electrochemiluminescence (ECL) encoding method was developed for the first time, based on a dual-dye system including Ru(bpy)(3)(2+) as an ECL emitter and fluorescein isothiocyanate (FITC) as a coding dye.

A nonenzymatic electrochemical method was developed for glucose detection using an electrode modified with palladium nanoparticles (PdNPs)-functional carbon nanotubes (FCNTs). PdNPs were homogeneously modified on FCNTs through a facile spontaneous redox reaction and characterized by transmission electron microscopy. Based on the voltammetric and amperometric results, PdNPs efficiently catalyzed the oxidation of glucose at 0.40 V in the presence of 0.2M NaCl and showed excellent resistance towards poisoning from such interfering species as ascorbic acid, uric acid, and p-acetamidophenol. This anti-poisoning ability was investigated using analysis of the electrocatalytic products by in situ subtractively normalized interfacial Fourier transform infrared reflection spectroscopy, and the results indicated that no strongly adsorbed CO(ad) species could be found in the oxidation products, which was obviously different from the results obtained using Pt-based electrodes. In order to verify the sensor reliability, it was applied to the determination of glucose in urine samples. The results indicated that the proposed approach provided a highly sensitive, wide linear range, more facile method with good reproducibility for glucose determination, promising the development of Pd-based material in nonenzymatic glucose sensing.

Electrochemiluminescence (ECL) behavior of luminol on an indium tin oxide (ITO) electrode modified with platinum nanoparticles (PtNPs) was investigated in a neutral aqueous solution using the conventional cyclic voltammetry (CV) technique. Experimental results indicated that the ECL behaviors of luminol on the PtNPs modified electrode showed significant difference from those on the bare ITO or bulk platinum electrodes. Five ECL peaks were found at 0.60, 0.92, 0.70, -0.44 and -1.16 V versus a saturated calomel electrode (SCE), respectively. The ECL peaks were found to depend on the reaction medium conditions including the type of electrolyte, pH value, the presence or absence of O2 and the different kinds of nanoparticles, as well as the scan direction and range of the applied potential. Furthermore, ECL peaks at -0.44 and -1.16 V could only be obtained on the PtNPs/ITO electrode. The surface state of the electrode was characterized by ultraviolet-visible (UV-Vis) absorption, scanning electron microscopy (SEM) and electrochemical impedance spectroscopy (EIS). A mechanism for luminol ECL on the PtNPs/ITO electrode was proposed. The excellent ECL properties of luminol on the PtNPs/ITO electrode in the neutral medium revealed a great potential for analytical applications to biological samples.

An ethanol biosensor, based on the electrogenerated chemiluminescence of Ru(bpy)(3)(2+)-doped silica nanoparticles (RuSiNPs), was investigated in this study. The biosensor was a modified glassy carbon electrode, where alcohol dehydrogenase was crosslinked to RuSiNPs, and then immobilized on the electrode surface using chitosan. The results indicated that the biosensor exhibited excellent performance during ethanol determination with a wide linear range (10(-7) to 10(-2) M), low detection limit (5.0x10(-8) M) and good stability.

A novel non-enzymatic electrochemiluminescence (ECL) sensor based on palladium nanoparticles (PdNPs)-functional carbon nanotubes (FCNTs) was discovered for glucose detection. PdNPs were homogeneously modified on FCNTs using a facile spontaneous redox reaction method. Their morphologies were characterized by transmission electron microscopy (TEM). Based on ECL experimental results, the PdNPs-FCNTs-Nafion film modified electrode displayed high electrocatalytic activity towards the oxidation of glucose. The free radicals generated by the glucose oxidation reacted with the luminol anion (LH(-)), and enhanced the ECL signal. Under the optimized conditions, the linear response of ECL intensity to glucose concentration was valid in the range from 0.5 to 40 micromol L(-1) (r(2)=0.9974) with a detection limit (S/N=3) of 0.09 micromol L(-1). In addition, the modified electrode presented high resistance towards the poisoning of chloride ion, high selectivity and long-term stability. In order to verify the sensor reliability, it was applied to the determination of glucose in glucose injection samples. The results indicated that the proposed approach provided a highly sensitive, more facile method with good reproducibility for glucose determination, promising the development of a non-enzymatic ECL glucose sensor.

Grey System Theory is applied to study the influence of the coal properties on the emissions of nitric oxides from fluidized bed coal combustion. Grey correlation coefficients for the emissions of nitrous oxides and nitric oxides in relation to the contents of nitrogen and carbon, fixed carbon, volatile matter, nitrogen fractions in char, and volatile, and the O/N ratio, fuel ratio, etc., are calculated. A large correlation coefficient of coal property means that the emission of nitrous oxides and nitric oxides is in close relation with the relevant property, in other words, the relevant coal property is the main affecting factor for nitrous oxides and nitric oxides formations. The calculation results show that the N2O emission is determined mainly by the nitrogen carbon content, fixed carbon, and the nitrogen fraction in char. While the carbon content, fixed carbon, nitrogen fraction in char mainly influence the NOx emission and nitrogen and hydrogen contents, it suggests that combustion of high rank coa...

In this study, a novel material, palladium nanoparticles-carboxylic functional carbon nanotubes (PdNPs-CFCNTs), based on PdNPs supported on CFCNTs was synthesized by a facile spontaneous redox method. The material reveals high electrochemical activity and excellent catalytic characteristic for alcohol electrooxidation on a glassy carbon electrode (GCE) in an alkaline medium. The preparation mechanism was studied by the galvanic cell effect between PdCl(4)(2-) and functional defect sites on CFCNTs. Results from UV-visible absorption spectroscopy and electrochemical impedance spectroscopy revealed that the reduction of PdCl(4)(2-) to metallic Pd was successfully achieved. Morphologies of PdNPs supporting on CFCNTs (PdNPs-CFCNTs) were also characterized by transmission electron micrograph. PdNPs-CFCNTs with the best electrocatalytic characteristics were obtained under the condition as: the weight ratio of Pd to CFCNTs was kept at 2:1, the temperature was kept at 70 degrees C in the synthesis, and the scan rate of the applied potential was selected at 60 mV s(-1). The results indicate that PdNPs-CFCNTs could be a great potential material in direct ethanol fuel cells and ethanol sensors.

Amino acids with different chemical structures have different abilities in terms of increasing the intensity of chemiluminescence (CL) of tris(2,2'-bipyridine)ruthenium(II) [Ru(bpy)3(2+)]. In a flow system, CL caused by the reaction between Ru(bpy)3(3+) and 15 amino acids was observed, but only tryptophan (Trp) and histidine (His) enhanced the intensity obviously, and so the CL of Trp and His and their molecular groups was studied. A calculation of the ionization potentials (IPs) of their N atom indicated that the CL intensities of these compounds depended on their IPs. In addition, the flow system was used for the determination of Trp and His, and the detection limits were 3 x 10(-8) mol L(-1) for His and 2.5 x 10(-9) mol L(-1) for Trp. The calibration curves for the two amino acids were 1.0 x 10(-7) to 5.0 x 10(-3) mol L(-1) for His and 1.0 x 10(-8) to 1.0 x 10(-4) mol L(-1) for Trp. The proposed approach was applied to the determination of His in Ganoderma.