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Browning of white adipose tissue (WAT) is becoming an attractive therapeutic target for obesity. Great efforts have been made to develop effective approaches to induce browning. Unfortunately, the current methods suffer from a series of disadvantages, such as low efficiency, unsatisfactory stability, and side effects. Herein, we report a new approach to induce browning of 3T3-L1 white adipocytes based on electromagnetic induction heating (EIH) hyperthermia. In particular, adipocyte-targeting aptamer modified gold nanoclusters (Apt-AuNCs) were employed as the mediators of EIH. Apt-AuNCs had good biocompatibility and excellent targeting performance with white adipocytes. After Apt-AuNCs/EIH treatment, adipocytes with characteristic multilocular and small lipid droplets increased, and the content of triglycerides reduced effectively. Apt-AuNCs/EIH treatment also significantly increased the mitochondrial activity in adipocytes. Meanwhile, the mRNA levels of key genes that are involved in browning, for example UCP1, PRDM16, PPARγ, and PGC-1α, were upregulated. Finally, the induction mechanism of Apt-AuNCs/EIH on browning of white adipocytes was explained by the synergistic effects of EIH hyperthermia and pharmacological action of AuNCs. To the best of our knowledge, this is the first attempt on induction of browning by metal nanocluster-mediated EIH hyperthermia, thus providing an interesting and efficient channel for obesity treatment.

Object in-hand reorientation is widely known to be crucial for robotic dexterous manipulation, and the stable reorientation of the in-hand object with the two-fingered gripper is challenging. In this paper, the object reorientation is completed using a commercial two-fingered gripper with integrated force/torque sensors. The identification models for the object in-hand status (slipping status and pivoting status) are built based on the friction theory. In-hand status identification provides an important guarantee for the object in-hand reorientation. Moreover, we propose a control framework for the object in-hand reorientation under the action of gravity. This framework is to make the object slip or pivot by continuously controlling the gripping force. The force control law is related to the object’s kinematics parameters, and the gripping force is modified according to the object in-hand status and kinematics parameters. Finally, the effectiveness of the proposed method is validated by testing object slipping and object pivoting in experiments. Results show that the gripping point and pose of the in-hand object are adjusted through object slipping and object pivoting.

Fast pyrolysis has been recognized as an efficient and feasible way to produce liquid fuels from biomass. For the aim to upgrade the products from fast pyrolysis of hemicellulose, reduced graphene oxide supported Pt nanoparticles (Pt/RGO) was adopted as catalyst for in situ catalytic fast pyrolysis (CFP). Pt/RGO was prepared by one-step thermal reduction method, and further employed as catalyst for in situ CFP of xylan. Online single-photon ionization time-of-flight mass spectrometry was employed to detect the volatile products, and furans were chosen as the model compounds. The experimental results showed that Pt/RGO distinctly increased the intensity of furans products from xylan pyrolysis, as the increase rates were respectively 80.5%, 64.4% and 50.2% in 400 °C, 500 °C and 600 °C. Furthermore, Pt/RGO can accelerate the process of xylan pyrolysis and be effective in eliminating oxygen for furans products. With addition of Pt/RGO, O/C ratio for furans products decreased from 0.38 to 0.32 in 400 °C, 0.37 to 0.32 in 500 °C, and 0.35 to 0.32 in 600 °C, respectively. This work proved that Pt/RGO had the potential to be a highly efficient catalyst for upgrading of the volatile products from in situ CFP of biomass.

Here, high performance polymers bearing photo-crosslinkable function are developed for all-PSCs to achieve both high efficiency and stability. Then, a series of novel -(D-A)a-(D-D1)b-type photo-crosslinkable bromine (Br)-functionalized polymer donors PBDT(T)FTAZ-BX were synthesized, in which typical benzodithiophene (BDT) derivative was as first component (D), thiophene-difluro-benzotriazole (FTAZ) derivative was as second component (A), new simple BDT-based functionality appended Br-unit synthesized in this study was as third component (D1). The effects of Br-functionalized component on the photoelectric properties of the polymers were investigated. Moreover, UV-mediated photo-crosslinking effects on performance and thermal stability were thoroughly explored. All-PSCs based on these photo-crosslinkable polymers and N2200, but without photo-crosslinking, displayed a highest PCE of 7.21%, which was achieved by an optimized PBDT(T)FTAZ-B5-based device. As results, photo-crosslinked PBDT(T)FTAZ-B5 + UV5min-based devices afford extraordinarily excellent thermal stability, in which high retention rate of 91.8% of the maximum PCEavg and the intrinsic performance (PCEmax: 6.12%) are maintained even after 72 h 150 °C annealing. For comparison, reference PBDT(T)FTAZ-based devices only display PCEmax value of 5.13% and retain 84.2% of their maximum PCEavg under same aging. This contrasting result indicates that developing photo-crosslinkable Br-functionalized polymers is an effective strategy to further advance in both stability and efficiency of all-PSCs.

This paper investigates the vibration and sound radiation of porous functionally graded material (FGM) plates with temperature gradient along the thickness. The even and uneven porosity distributions are taken into consideration in the present study. The formulation of the FGM plate is based on the first-order shear deformation theory (FSDT) with the temperature dependence of material properties considered. Each displacement component of the FGM plate is expanded as the Fourier cosine series combined with auxiliary functions in order to satisfy the general boundary conditions. A substantial number of numerical examples concerning the vibration and sound radiation responses of the heated plate are carried out to validate the convergence and accuracy of the proposed method. Finally, the effects of key parameters including the boundary condition, volume fraction index, thermal environment, temperature dependence of material properties and porosity volume fraction on the structural and acoustic responses of the FGM plate are discussed in detail.

Benzyl butyl phthalate (BBP) is a widely used plasticizer and has raised public health concerns. Here, we report the effects of BBP on the testis development during rat puberty. BBP (0, 10, 100 or 1000 mg/kg) was gavaged to 35-day-old male Sprague Dawley rats for 21 days. The serum testosterone levels, Leydig cell number, the expressions of Leydig and Sertoli cell genes and proteins were measured. The in vitro effects on steroidogenesis and gene expression in immature Leydig cells were observed. BBP significantly increased serum testosterone level at 10 mg/kg but lowered its level at 1000 mg/kg without affecting serum luteinizing hormone and follicle-stimulating hormone levels. BBP increased Leydig cell number at all doses but inhibited steroidogenic capacity per Leydig cell at 1000 mg/kg. BBP significantly increased the ratio of phosphos-AKT2 (pAKT2)/AKT2, and phosphos-ERK1/2 (pERK1/2)/ERK1/2 in the testis. Mono-benzyl phthalate (the metabolite of BBP) inhibited steroidogenesis but BBP did not affect androgen production in immature Leydig cells in vitro. In conclusion, BBP non-linearly regulates Leydig cell development by increasing Leydig cell number but inhibiting steroidogenesis.

Luminescent metal nanoclusters (NCs) have recently emerged as a novel class of luminescent nanomaterials and hold significant potential in biomedicine owing to their ultrasmall (< 2 nm) size, excellent photostability, and good biocompatibility. The recent rapid advances in the synthesis and functionalization of luminescent metal NCs have enabled scientists to develop colorful nanomaterials and nanodevices for a wide range of biomedical applications. In this review, we summarize the characteristics and advantages of luminescence from metal NCs, and highlight their applications in biomedicine. We focus on the research in biomedical detection, bio-imaging, drug delivery, and therapy, especially for the advances in the last five years. Luminescent metal NCs display a series of unique superiorities in biomedical applications, and the recent achievements have brought a lot of benefits to the diagnosis and treatment of clinical diseases, especially for tumors and cancers. Finally, we put forward the main challenges that currently still hinder the basic science studies and the practical development of luminescent metal NCs in biomedical applications. Overall, we expect that luminescent metal NCs will play a much more important role in future biomedicine and clinical applications.

Multiscale array (MSA) structures are present to reduce the front-side surface reflection loss of solar cells, which consists of nanostructure patterns spanned across the curved surface of micrometer-sized plano-concave cylindrical arrays. The MSAs are fabricated using flexible polydimethylsiloxane (PDMS) polymer by simple template replication together with surface modification technique and characterized by atomic force microscopy (AFM) and scanning electron microscopy (SEM). Optical characterization shows the MSA structure can reduce 3.85% integrated reflectivity of multicrystalline silicon solar cell encapsulated by the flat epoxy resin polymer (ERP) coating. Importantly, the MSA antireflective coating can improve the photovoltaic conversion efficiency of the ERP-encapsulated solar cell from 17.50% to 18.34% and can increase the contact angle of a 2 μL water droplet on the solar cell surface from 110.5° to 153.1°. These improvements have great significance for commercial Si solar cell devices.

One-monomer molecularly imprinted magnetic nanoparticles were prepared as adsorbents for selective extraction of bisphenol A from water in this study. A single bi-functional monomer was adopted for preparation of the molecularly imprinted polymer, avoiding the tedious trial-and-error optimizations as traditional strategy. Moreover, bisphenol F was used as the dummy template for bisphenol A to avoid the interference from residual template molecules. These nanoparticles showed not only large adsorption capacity and good selectivity to the bisphenol A but also outstanding magnetic response performance. Furthermore, they were successfully used as magnetic solid-phase extraction adsorbents of bisphenol A from various water samples, including tap water, river water, and seawater. The developed method was found to be much more efficient, convenient, and economical for selective extraction of bisphenol A compared with the traditional solid-phase extraction. Separation of these nanoparticles can be easily achieved with an external magnetic field, and the optimized adsorption time was only 15 min. The recoveries of bisphenol A in different water samples ranged from 85.38 to 93.75%, with relative standard deviation lower than 7.47%. These results showed that one-monomer molecularly imprinted magnetic nanoparticles had the potential to be popular adsorbents for selective extraction of pollutants from water.

A new type of magnetic nanoparticles (MNPs), as the absorbents of bisphenol A (BPA), was prepared by functionalization of Fe3O4@SiO2 with BPA-specific aptamer in this work. ssDNA aptamer was immobilized on the Fe3O4@SiO2 surface through biotin-avidin interactions, playing a role of the specific probe for BPA. The resultant materials (Apt-MNPs) exhibited outstanding magnetic responsibility and can be separated efficiently by the magnetic field. Experimental results also showed that Apt-MNPs had large adsorption capacity and high competitive selectivity for the targeted compound BPA. Furthermore, Apt-MNPs were adopted as the specific absorbents to extract and enrich BPA from human serum and urine samples. Therefore, an efficient detection method of BPA was developed in combination with high-performance liquid chromatography (HPLC). The linearity of the method was over a range of 5–10,000 ng mL−1 with a correlation coefficient of 0.99997, and the limit of detections (LODs) for serum and urine were 2.0 and 1.0 ng mL−1, respectively. The recoveries of BPA in the spiked human serum and urine samples were 90.8 ± 7.3% (RSD) and 92.3 ± 1.5%, respectively. Our results demonstrated that Apt-MNPs were high-performance adsorbents for extracting and enriching BPA, resulting in fast and efficient detection of BPA in serum and urine samples.

Aptamers have recently been widely employed as recognition elements for the discovery and detection of protein biomarkers. Therefore a comprehensive and in-depth understanding of the interaction between aptamers and their target proteins is especially important. Herein we report a real-time and label-free strategy to detect the interaction between alpha-fetoprotein (AFP), a specific biomarker of hepatocellular carcinoma, and its specific ssDNA aptamer based on dual polarization interferometry (DPI). The ssDNA aptamer was immobilized on the surface of a sensor chip followed by AFP injection, while the changes of mass, thickness and density on the AFP–aptamer interface were monitored and recorded online by DPI. The experimental results showed that there were two different interaction patterns between AFP and the aptamer, which were specific binding and unspecific binding, and the former was found to be the dominant one. AFP binding makes the conformation of the aptamer change, resulting in an increase of mass/thickness and a decrease of density. The concentration of AFP is very important for the AFP–aptamer interaction, as a high AFP concentration will lead to a high probability of the aptamer capturing AFP and therefore a large binding amount and a high mass loading rate. The developed detection method proved effective to study the interaction behavior and mechanism between AFP and its aptamer, and will find wide applications in the detection and understanding of protein–aptamer interaction.

A real-time and label-free strategy for bisphenol A (BPA) detection was developed using an ssDNA aptamer modified sensor combined with dual polarization interferometry (DPI). The BPA-specific aptamer, which played the role of a specific probe for recognizing and binding the target BPA, was immobilized on the surface of a sensor chip through biotin–avidin interactions. Conformational changes on the sensor surface when binding the target were monitored in real time by DPI, so that data on mass, thickness and density were obtained. Our results verified that the developed sensor had good specificity for the target, as the changes in mass, thickness and density induced by BPA were much more significant than those induced by an analogue. It was found that, with the increase of BPA concentration, the mass and thickness on the sensor surface increased while the density decreased. Both mass and thickness changes on the sensor surface showed good linearity with the BPA concentration in the range of 1–20 μM, with correlation coefficients (R2) of 0.9946 and 0.9950, respectively. This work provides a demonstration for the first time that DPI is a reliable and efficient platform for real-time and label-free detection of organic pollutants and toxicants.

Background High-performance position control of pneumatic artificial muscles is limited by their inherent nonlinearity and hysteresis. Objective This study aims to model the length/pressure hysteresis of a single pneumatic artificial muscle and to realize its accurate position tracking control with forward hysteresis compensation. Methods The classical Prandtl-Ishlinskii model is widely used in hysteresis modelling and compensation. But it is only effective for symmetric hysteresis. Therefore, a modified Prandtl-Ishlinskii model is built to characterize the asymmetric length/pressure hysteresis of a single pneumatic artificial muscle, by replacing the classical play operators with two more flexible elementary operators to independently describe the ascending branch and descending branch of hysteresis loops. On the basis, a position tracking controller, which is composed of cascade forward hysteresis compensation and simple proportional pressure controller, is designed for the pneumatic artificial muscle. Results Experiment results show that the MPI model can reproduce the length/pressure hysteresis of the pneumatic artificial muscle, and the proposed controller for the pneumatic artificial muscle can track the reference position signals with high accuracy. Conclusion By modelling the length/pressure hysteresis with the modified Prandtl-Ishlinskii model and using its inversion for compensation, precise position control of a single pneumatic artificial muscle is achieved.

To explore the roles of mitochondrial Uncoupling Protein 2 (UCP2) in cumulus cells (CCs), human CCs were cultured in vitro, and the UCP2 was inhibited by treatment with Genipin, a special UCP inhibitor, or by RNA interference targeting UCP2. No significant differences in adenosine triphosphate levels and the ratio of ADP/ATP were observed after UCP2 inhibition. UCP2 inhibition caused a significant increase in cellular oxidative damage, which was reflected in alterations to several key parameters, including reactive oxygen species (ROS) and lipid peroxidation levels and the ratio of reduced GSH to GSSG. UCP2 blocking resulted in an obvious increase in active Caspase-3, accompanied by the decline of proactive Caspase-3 and a significant increase in the LC3-II/LC3-I ratio, suggesting that UCP2 inhibition triggered cellular apoptosis and autophagy. The mRNA and protein expression of connexin 43 (Cx43), a gap junction channel protein, were significantly reduced after treatment with Genipin or siRNA. The progesterone level in the culture medium was also significantly decreased after UCP2 inhibition. Our data indicated that UCP2 plays highly important roles in mediating ROS production and regulating apoptosis and autophagy, as well as maintaining gap junction integrity and progesterone synthesis, which suggests that UCP2 is involved in the regulation of follicle development and early embryo implantation and implies that it might serve as a potential biomarker for oocyte quality and competency.

Pneumatic artificial muscles have been widely used in various fields owing to their inherent compliance and high power-to-weight ratio. However, the natural hysteresis nonlinearity including length/pressure hysteresis and force/pressure hysteresis degrades their performance in precise tracking control, making it necessary to build a mathematical hysteresis model for hysteresis compensation. This paper deals with the modelling of length/pressure hysteresis of pneumatic artificial muscles. The length/pressure hysteresis loops measured by the isotonic test are found to be asymmetric and independent of the external load when the load is small. Considering that the classical Prandtl-Ishlinskii model is only effective for symmetric hysteresis, a modified Prandtl-Ishlinskii model is proposed to describe the length/pressure hysteresis behaviour. The developed model utilizes two asymmetric operators with simple mathematical forms to independently model the ascending branch and descending branch of hysteresis loops. The model parameters are identified using the recursive least square algorithm. Comparisons between simulation results and experimental measurements demonstrate that the proposed model can characterize the asymmetric major hysteresis loop and minor hysteresis loops with high accuracy. Pnevmatične umetne mišice (PAM) so razmeroma nova vrsta elastičnih pnevmatičnih izvršnih členov. Zaradi svoje netogosti ter velikega razmerja med močjo in maso so se uveljavile na različnih področjih uporabe. Njihova naravna nelinearnost, ki vključuje histerezo dolžine/tlaka in histerezo sile/tlaka, pa povečuje sistemsko nelinearnost ter zmanjšuje sposobnost natančnega sledenja. Ena od rešitev za premostitev te težave je postavitev matematičnega modela histereze ter uporaba njegovega inverza za kompenzacijo histereze in doseganje približno linearnega odziva PAM. Članek obravnava modeliranje histereze dolžine/tlaka pri PAM. Histereza dolžine/tlaka se meri z izotoničnim testom ob predpostavki kvazistatičnosti procesa, meritve pa nakazujejo obstoj večje in manjše histerezne zanke med hitrostjo krčenja in notranjm tlakom PAM. Te histerezne zanke so asimetrične ter niso odvisne od manjših zunanjih obremenitev.

A series of bithiophene (2T)-based D-A1-D-A2 terpolymers with different A2 moieties were prepared via direct arylation reaction. In these terpolymers, pyrrolo[3,4-c]pyrrole-1,4-dione (DPP) was selected as the first electron-accepting (A1) moiety, 2,1,3-benzothiadiazole (BT) or fluorinated benzothiadiazole (FBT) or octyl-thieno[3,4-c]pyrrole-4,6-dione (TPD) or 2,1,3-benzoselendiazole (SeT) was selected as the second electron-accepting (A2) moiety, while bithiophene with hexyl side chain was used as the electron-donating moiety. The UV-vis absorption, electrochemical properties, blend film morphology, and photovoltaic properties were studied to explore the effects of the A2 moiety. It is shown that these terpolymer films exhibit broad absorption (350&ndash, 1000 nm), full width at half-maximum of more than 265 nm and ordered molecular packing. Varying the A2 moiety could affect the energy levels and blend film morphology leading to different polymer solar cell (PSC) performances of these (2T)-based D-A1-D-A2 terpolymers. As a result, the highest Jsc of 10.70 mA/cm2 is achieved for Polymer 1 (P1) with BT as A2 moiety, while the higher highest occupied molecular orbital (HOMO) level limits the open circuit voltage (Voc) and leads to a power conversion efficiency (PCE) of 3.46%.

This study was designed to estimate the human risk to polybrominated diphenyl ethers (PBDEs) exposure via two main exposure routes (dust and diet) in an e-waste recycling area in southern China. A total of 134 dust samples and 129 food samples were analyzed by gas chromatography/mass spectrometry (GC/MS). The mean concentration of ΣPBDE in in-house dust (38,685 ng/g dw) was higher than that in out-house dust (24,595 ng/g). For food samples, the highest concentration of ΣPBDE was found in fish and shellfish (2755 ng/kg ww), followed in descending order by eggs (2423 ng/kg), cereals (2239 ng/kg) and meat (1799 ng/kg). The estimated total daily dietary intake of PBDEs was 1671 ng/day for adults and 952 ng/day for children. The present study indicated that dust intake was the dominant PBDE exposure route for children, and the dietary intake was the dominant PBDE exposure route for adults. Our findings revealed high PBDE concentrations in dust and food samples collected at the center of e-waste recycling area, raising significant health concerns for residents in this particular region, especially for children.

In recent years, a strong growth in power conversion efficiency of all-polymer solar cells (up to 11.0%) has been realized through extensive material and device research. For practical application, high intrinsic thermal stability of the photoactive layer is a crucial requirement for long lifetimes. In this study, two new vinyl-functionalized monomers (TPD-V, NDI-V) were synthesized as the third monomer to produce two new series of cross-linkable benzodithiophene (BDT)-thieno[3,4-c]pyrrole-4,6-dione (TPD)-based polymer donors and naphthalenediimide (NDI)-based polymer acceptors by random copolymerization. By synthetically tuning the molar content of vinyl units, the crosslinked properties of the polymers were explored. It is found that these crosslinkable polymers with small molar content of vinyl unit can be mostly crosslinked upon long-term heating. Meanwhile, by employing crosslinking of PA/PD blend, all-PSCs were fabricated and the thermal-stability were studied. As a result, the all-PSCs based both crosslinkable polymer donor PBDT-TPD-8 and acceptor PNDI-T-5 retained 86% of its highest PCE (106% of its initial PCE) without obvious burn-in efficiency loss under 24 h of continuous accelerated heating (150 °C), while the reference devices based non-crosslinkable PBDT-TPD-0/PNDI-T-0 only retained 40% of its highest PCE (51% of its initial PCE). The results demonstrate photoactive layer crosslinking can stabilize morphology under long term thermal stress leading to excellent thermal-stability of the devices.

Polybrominated diphenyl ethers (PBDEs) have been used extensively in electrical and electronic products, but little is known about the exposure level in the electrical appliance factories workers and nearby local residents. In this study, we assessed body burdens of PBDEs in 194 Chinese injection workers from electrical appliance factories and also measured 205 blood samples from catering workers, leather factory workers, umbilical cord and infertile men for comparison. Twelve PBDE congeners in serum samples were measured by GC–MS. The highest concentration for total PBDEs was found in injection workers, which is positively correlated to employment duration. BDE-209 was the most dominant congener followed by BDE-47, 28 and 99. We also found the presence of all twelve PBDEs in cord blood, suggesting an evidence of fetal exposure. Concentration of BDE-47 was particularly higher in serum samples from infertile men in comparison with that of catering workers and leather factory workers.

Leakage of the residual template molecules is one of the biggest challenges for application of molecularly imprinted polymer (MIP) in solid-phase extraction (SPE). In this study, bisphenol F (BPF) was adopted as a dummy template to prepare MIP of bisphenol A (BPA) with a superparamagnetic core-shell nanoparticle as the supporter, aiming to avoid residual template leakage and to increase the efficiency of SPE. Characterization and test of the obtained products (called mag-DMIP beads) revealed that these novel nanoparticles not only had excellent magnetic property but also displayed high selectivity to the target molecule BPA. As mag-DMIP beads were adopted as the adsorbents of solid-phase extraction for detecting BPA in real water samples, the recoveries of spiked samples ranged from 84.7% to 93.8% with the limit of detection of 2.50 pg mL(-1), revealing that mag-DMIP beads were efficient SPE adsorbents.

Perfluorinated compounds (PFCs) are persistent organic pollutants ubiquitously distributed in the environment and human populations. Here we report PFC concentrations in the residents of Wenzhou City, which is characterized as the 'Footwear Capital' of China. Specifically, fifty serum samples collected from workers in a leather factory, fifty-five umbilical cord serum samples and fifteen serum samples from infertile men were analyzed. PFOS was one of the most frequently detected PFCs and showed the highest level. The mean serum levels of PFOS and PFOA of workers and infertile males were higher than the cord serum. PFOS concentration in cord serum increased with increase in age of the mother. Gender differences were significant both in worker serum samples and umbilical cord samples with higher levels found in males/male fetuses. Our findings suggested that PFOS, PFOA and PFHxS were widely distributed in Wenzhou residents, but occupational exposure was not the main source for workers.

Combustion intermediates of a cyclic oxygenated hydrocarbon, 1,4-dioxane, were studied with the tunable synchrotron vacuum ultraviolet photoionization and molecular-beam mass spectrometry (MBMS) technique. A fuel-rich premixed laminar 1,4-dioxane/O(2)/Ar flame at low pressure with an equivalence ratio of 1.80 was investigated in the present work. A total of 20 intermediates were observed, and their mole fraction profiles are calculated. Aromatic intermediates were not observed, and this was a prominent difference between the fuel-rich flames of 1,4-dioxane and previously studied noncyclic oxygenated hydrocarbons. The fuel-rich 1,4-dioxane flame could be divided into four zones, and formation routes of the intermediates were proposed. The discussion on the pollutant emissions showed that some light toxic molecules were produced from 1,4-dioxane combustion; however, toxic aromatics and soot emissions were possibly avoided.

Effects of fullerenes including FS, EFS and pure C60 on thermal behaviors of polyethylene glycol (PEG) have been studied by employing thermogravimetry-differential thermogravimetry (TG-DTG), differential scanning calorimeter (DSC) and off-line furnace-type pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS). The products were collected by Cambridge filter pad which was widely used in analyzing the combustion products of cigarette. The results showed that the addition of fullerenes obviously restrained the thermal decomposition of PEG. The initial decomposition temperatures (IDT) and maximum decomposition peak temperatures (MDT) were evidently postponed by the addition of fullerenes. Pyrolysis products with one or two hydroxyl end groups obviously increased with the addition of 10% C60. The reasons of the changes were discussed from the aspects of reaction mechanisms.

Effects of nano-metal powders (aluminum and nickel) addition on the thermooxidative degradation of binder PEG in air atmosphere from 20 to 350°C were studied by TG/DTA and in-situ FTIR. TG/DTA results showed that the addition of nano-Al slowed down the degradation process of PEG in the early period but accelerated the process in the late period; the addition of nano-Ni made the PEG degradation process begin as soon as melted. The in-situ FTIR results showed that nano-Ni promoted the thermooxidative degradation of PEG in air, and made the degradation process of PEG complete much earlier.

A fuel-lean laminar premixed methylmethacrylate/oxygen/argon flame at 2.67 kPa with an equivalence ratio () of 0.75 has been investigated with the tunable synchrotron vacuum ultraviolet (VUV) photoionization and molecular beam sampling mass spectrometry techniques. Isomers of most observed species in the flame have been identified by measurements of photoionization mass spectra and the near-threshold photoionization efficiency spectra. Mole fraction profiles for about 42 flame species are displayed. Free radicals such as CH 3, C2H3 ,C 2H5 ,C 3H3 ,C 3H5 ,C 2H3O, C4H7 ,C 3H5O, C3H7O, C4H3O, C4H9O, C4H5O2 ,C 4H7O2, and C5H7O2, which should be of importance in understanding the formation mechanism of some toxic substances, were detected in the flame. Moreover, no isomers of any PAHs have been detected in the lean flame. Combined with the mole fraction profiles, the formation mechanisms of the free radicals, oxygenated compounds, and other molecular intermediates are proposed and will provide important information on modeling the combustion kinetics of methylmethacrylate (MMA).

Intermediates in a fuel-rich premixed laminar 1,2-dimethoxyethane (DME) flame are studied by molecular beam mass spectrometry combined with tunable synchrotron vacuum ultraviolet photoionization. About 30 intermediate species are identified in the present work, and their mole fraction profiles are evaluated. The experimental results show that the formations of intermediates, both hydrocarbons and oxygenated hydrocarbons, are closely linked to the structure of fuel, which is consistent with the previous reports. Species produced from H atom abstraction and beta scission of DME usually have much higher concentrations than others. The oxygen atoms in DME are considered to act as partitions of the primary intermediates; therefore farther reactions among these primary intermediates are difficult to occur, resulting in absence of most large intermediate species.