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Additional file 1: Table S1. Subgroup analyses of major survival outcomes. Table S2. Subgroup analyses of peri-operative outcomes.

Additional file 1: Figure S1. The relationship between a healthy lifestyle and CMM in subgroup analyses. Figure S2. The relationship between a healthy lifestyle and CMM in seven sensitivity analyses. Figure S3. The frequency distribution graph of the weighted healthy lifestyle score for the whole population. Figure S4. The frequency distribution graph of the weighted healthy lifestyle score for 2/3 of the population. Figure S5. The frequency distribution graph of the sum healthy lifestyle score for the whole population. Table S1. Cardiometabolic diseases definitions. Table S2. The association between a healthy lifestyle and cardiometabolic multimorbidity. Table S3. The association between each healthy lifestyle and cardiometabolic multimorbidity. Text S1. Alcohol consumption calculation method. Text S2. How the weighted healthy lifestyle scores and summed lifestyle scores were calculated.

Polyimide/AlN (PI/AlN) nanocomposite films were prepared by in-situ polymerization method with different doping concentrations and their microstructures were investigated by small angle X-ray scattering (SAXS) technique. Analyzed SAXS results indicate the average diameters of the nanoparticles in hybrid films distribute from 55 nm to 60 nm, which are consistent with the observation from Scanning Electron Microscope (SEM). The Fourier Transform Infrared Spectroscopy (FTIR) results confirm the formation of AlN particles in the PI matrix. The effects of content on the dielectric constant, loss tangent, breakdown strength and corona ageing were studied. The corona resistant time of PI/AlN with 20 wt.% doping concentration is 58.5 hours, which is twenty times more than that of pure PI. The results show that the corona resistance of PI/AlN has been improved significantly.

Noncrosslinking linear low-density polyethylene-grafted acrylic acid (LLDPE-g-AA) was prepared by melt-reactive extrusion in our laboratory. The thermal behavior of LLDPE-g-AA was investigated by using differential scanning calorimetry (DSC). Compared with neat linear low-density polyethylene (LLDPE), melting temperature (T-m) of LLDPE-g-AA increased a little, the crystallization temperature (T-c) increased about 4degreesC, and the melting enthalpy (DeltaH(m) ) decreased with an increase in acrylic acid content. Isothermal crystallization kinetics of LLDPE and LLDPE-g-AA samples were carried out by using DSC. The overall crystallization rate of LLDPE was smaller than that of grafted samples. It showed that the grafted acrylic acid monomer onto LLDPE acted as a nucleating agent. Crystal morphologies of LLDPE-g-AA and LLDPE were examined by using SEM. Spherulite sizes of LLDPE-g-AA samples were lower than that of LLDPE.

Non-cross-linking linear low-density polyethylene-grafted-acrylic acid (LLDPE-g-AA) was prepared by melting reactive extrusion in our laboratory. The thermal behavior of LLDPE-g-AA was investigated by using differential scanning calorimetry (DSC). Compared with neat linear low-density polyethylene (LLDPE), melting temperature (Tm) of LLDPE-g-AA increased a little, the crystallization temperature (Tc) increased about 4[ddot] C, and the melting enthalpy (δ Hm) decreased with increase of acrylic acid content. Isothermal crystallization kinetics of LLDPE and LLDPE-g-AA samples was carried out using DSC. The overall crystallization rate of LLDPE was smaller than that of grafted samples. It showed that the grafted acrylic acid monomer onto LLDPE acted as a nucleating agent. Morphologies of LLDPE-g-AA and LLDPE were examined using SEM. Spherocrystal diameters of LLDPE-g-AA samples were lower than that of LLDPE.

Blends of linear low density polyethylene (LLDPE) and linear low density polyethylene-grafted-acrylic acid (LLDPE-g-AA) were prepared by melt mixing. The surface of films with different content LLDPE-g-AA were characterized through contact angle measurements and FT-IR spectroscopy. The contact angles of water and glycerol on films surfaces of LLDPE/LLDPE-g-AA blends decrease with increase of LLDPE-g-AA. From FT-IR spectra of the blends, the carbonyl peak strength on the films surface was calculated. It was found that larger the carbonyl peak strength, the lower the value contact angle for LLDPE/LLDPE-g-AA blends.

The contact angles θ of polar liquid on surface of non-crosslinking linear low density polyethylene-graft-acrylic acid (LLDPE-g-AA) were measured. The critical surface tension (γc) of LLDPE-g-AA films were evaluated by three different plots, the Zisman plot, the Young-Dupre-Good-Girifalco plot, and the log(1 + cos θ) versus log θ L , plot. The θ c of LLDPE-g-AA obtained by the 1 + cosθ versus θ L −1/2 plot were higher than those obtained by other plots.

This work deal with the effect of compatibilizer on the morphological and mechanic properties of polyamide 6 and ultrahigh molecular weight polyethylene (PA6/UHMWPE) blends. The blends were prepared by means of a twin-screw extruder. The compatibilizer was produced by grafting maleic anhydride (MAH) onto high density polyethylene (HDPE). The resulting HDPE-g-MAH was used to prepare ternary blends of PA6/HDPE-g-MAH/UHMWPE by melt mixing. The size of domain of UHMWPE in PA6/HDPE-g-MAH/UHMWPE blends is much smaller than that in PA6/UHMWPE blends. It was found that mechanical properties of PA6/HDPE-g-MAH/UHMWPE blends obviously surpassed that of PA6/UHMWPE blends. These behavior could be attributed to chemical reactions between MAH in HDPE-g-MAH and terminal amino groups of PA6. Thermal analysis were performed to confirm the possible chemical reactions taken place during the blending process.

Effects of the compatibilizer polypropylene grafted with glycidyl methacrylate(PP-g-GMA) on the morphology, thermal, rheological and mechanical properties of polypropylene and polycarbonate blends (PP/PC) were studied. It was found that the addition of PP-g-GMA significantly changed their morphology. The mean size of domains reduced from 20 μm to less than 5 μm. The dispersed domain size is also strongly dependent upon the content of PP-g-GMA. The interfacial tension of PP/PC/PP-g-GMA (50/30/20) is only about one-tenth of PP/PC (70/30). The crystallization temperature of PP in PP/PC/PP-g-GMA is 5–8°C higher than that of PP in PP/PC blends. Characterization studies based on mechanical properties, differential scanning calorimetry, rheology and morphological evidence obtained by using scanning electron microscopy support the hypothesis that an in-situ copolymer PP-g-PC was formed during the blending process.

Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used to examine the morphology of blends of PA1010 and polypropylene (PP) compatibilized with polypropylene grafted with glycidyl methacrylate (PP-g-GMA). It is found that the morphologies are dependent on the content of glycidyl methacrylate in PP-g-GMA and the mxing time. The size of the dispersed PP particles decreases as the content of GMA in the PP-g-GMA increases for binary blends of PA1010 and PP-g-GMA. Similar results are obtained for changing the mixing time. Ternary blends of PA1010, PP, and PP-g-GMA indicate that morphologies depend on the content of glycidyl metyacrylate in the PP-g-GMA and the miscibility of PP and PP-g-GMA. By changing the content of GMA in PP-g-GMA, it was possible to introduce significant changes of morphology. A matrix removal TEM method is used to investigate the interfacial structure of PA1010/PP blends containing PP-g-GMA as a compatibilizer. This technique shows the reaction product between PA1010 and PP-g-GMA to be located at interface as a surrounding layer around domain particles. SEM observation on the interface shows that the adhesion between PA1010 and pure PP is very weak and their interface boundary is sharp. For the samples of PA1010 and PP-g-GMA, it was found that the interface was not so obvious, and the reaction between PA1010 and PP-g-GMA strengthens the interface significantly.

The thermal properties of ethylene propylene copolymer-grafted-acrylic acid (EP-g-AA) were investigated by using differential scanning calorimetry (DSC). Compared with the ethylene propylene copolymer (EP), the peak values of the melting temperature (T-m) of the propylene sequences in the grafted EP changed a little, the crystallization temperature (T-c) increased about 8-12 degrees C, and the melting enthalpy (Delta H-m) increased about 4-6 J/g. The isothermal crystallization kinetics of grafted and ungrafted samples was carried out by DSC. Within the scope of the researched crystallization temperature, the Avrami exponent (n) of the ungrafted sample was 1.6-1.8, and that of grafted samples were all above 2, which indicated that the grafted monomer could become the crystal nuclei for the crystallization of propylene sequence. With increasing grafted monomer content, the crystallization rate of propylene sequence in grafted EP increased; it might be the result of rapid nucleation rate and crystal growth rate.

Morphology, mechanical properties, and interfacial interaction of polyamide 1010/polypropylene (PA1010/PP) blends compatibilized with polypropylene grafted with glycidyl methacrylate (PP-g-GMA) were studied. It was found that the size of the PP domains, tensile and impact strength of ternary blends, and adhesion fracture energy between two layers of PA1010 and PP were all significantly dependent on the PP-g-GMA contents in the PP layer. Correlations between morphology and related properties were sought. The improvements in properties have been attributed to chemical and physical interaction occurring between PA1010 and PP-g-GMA.

An ethylene-propylene copolymer (EPM) has been functionalized with acrylic acid (AA) by means of a radical-initiated melt process. Different degrees of grafting have been obtained by varying the overall composition of the reaction mixture. The influence of the grafting degree on the structure has been investigated by differential scanning calorimetry (DSC), Fourier-transform infrared analysis (FTIR), and wide-angle x-ray scattering (WAXS) techniques. The results of the structural investigations suggest that the grafting preferentially occurs onto the ethylene sequences of EPM. After acrylic acid was grafted onto EPM, the grafted AA acted as nucleation agent; it caused an increase of crystallization temperature of propylene sequences of EPM-g-AA.

The miscibility of blends of cellulose diacetate (CDA) and poly(vinyl pyrrolidone) (PVP) was extensively studied by means of differential thermal analysis and dynamic mechanical thermal analysis, tensile test, measuring viscosity of diluted and concentrated solutions of blends in acetone-ethanol mixture and morphological observations. A single glass transition temperature is observed, which is intermediate between the glass transition temperatures associated with each component and depends on composition. A synergism in mechanical properties of blends was found. The absolute viscosity and the intrinsic viscosity of solutions of blends are much higher than the weight average values of solutions of CDA and PVP. Optically clear and thermodynamically stable films were formed in the composition range of CDA PVP = 100 0 to 50 50 w/w. Fourier transform infrared was used to investigate the nature of CDA-PVP interaction. Hydrogen bonds were formed between hydroxyl groups of CDA and carbonyl groups of PVP. Heats of solutions of CDA/PVP blends and their mechanical mixtures were measured by using a calorimeter. Mixing enthalpy obtained with Hess's law approach was used to quantify interaction parameters of this blending system. It was found that mixing enthalpies and interaction parameters were negative and composition dependent.

This work deals with the effect of compatibilizer on the morphological, thermal, rheological, and mechanical properties of polypropylene/polycarbonate (PP/ PC) blends. The blends, containing between 0 to 30 vol % of polycarbonate and a compatibilizer, were prepared by means of a twin-screw extruder. The compatibilizer was produced by grafting glycidyl methacrylate (GMA) onto polypropylene in the molten state. Blend morphologies were controlled by adding PP-g-GMA as compatibilizer during melt processing, thus changing dispersion and interfacial adhesion of the polycarbonate phase. With PP-g-GMA, volume fractions increased from 2.5 to 20, and much finer dispersions of discrete polycarbonate phase with average domain sizes decreased from 35 to 3 mu m were obtained. The WAXD spectra showed that the crystal structure of neat PP was different from that in blends. The DSC results suggested that the degree of crystallization of PP in blends decreased as PC content and compatibilizer increased. The mechanical properties significantly changed after addition of PP-g-GMA. (C) 1997 John Wiley & Sons, Inc.

The rheological properties and crystallization characteristics of low ethylene content poly propylene (EPM) with and without Yittrium oxide (Y2O3) as a filler was investigated by cone-plate viscometer and differential scanning calorimetry. Yittrium oxide had a profound effect on the viscosities of the systems. To determine the nonisothermal crystallization rate of the materials, a new estimation method was used. From the results, we can conclude that Y2O3 acts as a nucleating agent, which increased the crystallization rate of the EPM. (C) 1996 John Wiley & Sons, Inc.

The modification of ethylene-propylene copolymer (EP) has been accomplished by radical EP-graft-acrylic acid (EP-g-AA) has been used to obtain ternary PA/EP/EP-g-AA blends by melt mixing. Different blend morphologies were observed by scanning electron microscopy; the domain size of the EP-dispersed phase in the polyamide 1010 matrix of compatibilized blends decreased compared with that of uncompatibilized blends. It is found that EP-g-AA used as the third component has a profound effect on the mechanical properties of the resulting blends. This behavior has been attributed to serious chemical interactions taking place between the two components. Thermal analysis shows that some thermal properties of PA in compatibilized PA/EP/EP-g-AA changed because of chemical reactions taken place during the blending process. Wide angle x-ray diffraction measurements also confirmed this result. (C) 1996 John Wiley & Sons, Inc.

In this paper, the package TO-220C VDMOS devices are tested under the conditions of variable frequency and fixed-frequency vibration and the influence of vibration on source current leakage IDS and transconductance gm of device are discussed. The changes of device casing and chip surface are observed by microscope and the failure mechanism of device is analyzed. The experimental results show that IDS and gm of device became smaller with the increase of variable frequency. When the vibration frequency reaches 320Hz, the values of IDS and gm reached device failure criterion. Because parameters of each layer material in cell are different, the distribution of strains among layers which is caused by vibration generates defect or crazes. With the increase of time of the fixed-frequency vibration, some cell appears micro-cracks which expand to more cells gradually, which lead to device failure, life of VDMOS becomes shorter. Keywords-VDMOS device; electrical properties; vibration frequency; vibration time; failure mechanism

In order to overcome the disadvantages of low mass transport efficiency of oxygen to the cathode and poor performance of passive micro direct methanol fuel cells (DMFC), the structures of the cathode current collector for the passive micro DMFC have been studied. The passive micro DMFC employing the cathode current collector with the planar perforated-plate structure has been fabricated. The effect of the anode methanol concentration and the opening area ratio of the cathode on the performance has been investigated. Owing to the influence of contact resistance and oxygen mass transport, the passive micro DMFC exhibits the optimal performance when opening ratio is 50%. Furthermore, the new parallel channels structure of the cathode current collector has been proposed, and the corresponding passive micro DMFC has also been fabricated by utilizing micro precision processing technology. The test results indicate that the mass transfer of oxygen and performance stability have been improved based on the cathode current collector with the parallel channels structure compared to the conventional planar structure. Moreover, a maximum output power density of 9.7 mW/cm2 is achieved. The above studies might be helpful for the developing and application of portable micro power systems.

VDMOS devices with high voltage and high current are widely used in power semiconductor devices, the microelectronics and power electronics technology. In this paper, the failure properties of VDMOS devices have been investigated by temperature cycling experiment and finite element software simulation. The experiment results show that some electric properties of devices degenerate and there are some cracks on the chip surface after high and low temperature cycling. The main failure mechanism is caused by heat and thermal stress, which have a great impact on the reliability of the devices. In order to study the failure property of VDMOS device under the thermal cycles, a three-dimensional model is established and simulated by ANSYS. The simulation results show that, after applied temperature cycling field, as to thermal expansion mismatching among the components of devices, it will give rise to accumulation plastic strain and stress inner device. The dangerous section of the device is on the interface of chip and adhesive layer. The thickness of substrate and adhesive layer affect heat dissipation of device. The simulation results are in good agreement with experimental ones.

VDMOS device (Vertical Double-diffused Metal Oxide Semiconductor) has the features of higher input impedance, lower drive current, higher switching speed, better frequency characteristic, bigger safety operating area and better thermal stability, which is used in many fields, such as switches in power electronic systems, so it has become the research focus of discrete power semiconductor devices. In this paper, the damage of VDMOS devices is discussed which is caused by the CTE (coefficient of thermal expansion) mismatch between the plastic encapsulated body and the chip during temperature changed environment. The surface and cross-section microstructure of the chips are observed by SEM and AFM. Thermal stress effect on plastic encapsulated body and the chip bonding and cause the interface and chip cracking, which occur on the position of chip edge specially.

The acoustic-vibration sensors system is a kind of MEMS devices, which has a potential application prospect and its packaging plays key part in the fabrication process. The double J-Iike package model for isolating the acoustic sensor has been chosen while packaging the acoustic-vibration sensors system in this paper. By using the finite element analysis software ANSYS 5.7, modal analysis has been applied on the package model to analyze the relationship between the isolating material parameters and the natural frequencies of the model, which is the key physical quantity for isolation. The results show that the first three natural frequencies increase with the increase of the Young's modulus Y of the isolating material rubber, and they don't change evidently when the Poisson's ration mu increase and they decrease with the increase of Density phi . The optimized material parameters have been gained: Y = 1.0 times 106 N/m2, mu = 0.49 and phi = 1.2 times 103 kg/m3

Plasmonics, which deals with the unique optical properties of metallic and semiconductor nanostructure, is one of the most fascinating and fast-moving areas of photonics. Its board scale research in the visible, infrared, terahertz and microwave frequencies has driven by the advances in the micro/nano fabrication and the computational simulation technologies, as well as the potential applications in areas of high sensitivity bio-chemical sensing, sub-wavelength light-guiding, near-field microcopy, and nanolithography. Especially, the development of the artificial metamaterial has laid the good foundation for the material and devices in the terahertz frequency range, which is barely responded by the nature materials, and furthermore, has promoted the progress of terahertz surface plasmonics. In this paper the generation, propagation, new applications, and perspective of terahetz surface plamonics are reviewed and discussed.

Inorganic nanohybrid polyimide (PI) is widely applied in electrical and electronic devices for its outstanding insulating properties. Samples 100CR and 100NH are made in Dupont. Among them, 100NH is a kind of pure PI films; however, 100CR is a kind of inorganic nanohybrid PI films with excellent corona-resistance. The nanostructure of PI films is investigated with small-angle x-ray scattering technique and transmission electron microscopy (TEM). The normalized volume fractions of the scatterers in the specimens are obtained with a tangent-by-tangent data analysis for the small-angle x-ray scattering data. The multi-hierarchical scatterers of 100NH can be divided into two dominant components, i.e., the sharp component and the wide component. The sharp component is corresponding to the contribution of PI molecular chains, and the wide component includes the aggregates formed by PI molecular chains and the film has nested dual-fractal characteristics, nevertheless the 100CR film possesses three types of scale scattering made up of inorganic nanoparticles, molecular chains and aggregates. The present films have multi-fractal structures. The distribution and structure of scattering body of two kinds of PI films are analyzed. The results of SAXS agree well with those of TEM methods.