Search

Two benzodifuran (BDF) polymers, PBDF-C and PBDF-S, with alkyl and alkylthio substituted thiophene side-chains and benzodithiophene-4,8-dione (BDD) as the acceptor were designed and synthesized. Their optical, electrochemical properties and photovoltaic performances were systematically investigated. The polymer solar cells (PSCs) with a device structure of ITO/PEDOT:PSS/polymer:PC71BM/Ca/Al were fabricated. The PBDF-C based device showed a power conversion efficiency (PCE) of 3.01% after adding 1 vol% 1,8-diodooctane (DIO) as the solvent additive, and PBDF-S gave an enhanced PCE of 3.48% without any post-treatments. The enhancements were from the higher open-circuit voltage (Voc) and fill factor (FF). The thermal- and solvent-treatment-free processing is more favourable for the large area roll-to-roll manufacturing or printing technology for PSCs.

Existing evidence on the relationship between cardiovascular health (CVH) metrics and cardiovascular disease (CVD) was primarily derived from western populations. We aimed to evaluate the benefits of ideal CVH metrics on preventing incident atherosclerotic CVD (ASCVD) in Chinese population. This study was conducted among 93,987 adults from the China-PAR project (Prediction for ASCVD Risk in China) who were followed up until 2015. Cox proportional hazard regression models were used to estimate the hazard ratios (HRs) and their corresponding 95% confidence intervals (CIs) of CVH metrics for the risk of ASCVD, including coronary heart disease (CHD), stroke and ASCVD death. We further estimated the population-attributable risk percentage (PAR%) of these metrics in relation to each outcome. We observed gradient inverse associations between the number of ideal CVH metrics and ASCVD incidence. Compared with participants having ≤2 ideal CVH metrics, the multivariable-adjusted HRs (95% CIs) of ASCVD for those with 3, 4, 5, 6 and 7 ideal CVH metrics were 0.83 (0.74–0.93), 0.66 (0.59–0.74), 0.55 (0.48–0.61), 0.44 (0.38–0.50) and 0.24 (0.18–0.31), respectively ( P for trend

A series of cubic MgZnO films with a band gap of 5.0 eV (240 nm) are grown on the Si substrate by radio-frequency (rf) magnetron sputtering with various annealing temperature. Highly (111) textured single phase cubic MgZnO films with enhancement of conductivities are received through thermal annealing. The effects of annealing temperature on the structural, optical and electrical properties of cubic MgZnO films have been investigated. With increasing annealing temperature, phase separation of MgZnO films has been suppressed due to the internal strain is partially relieved by the thermal annealing. In addition, the resistivity (electron mobility, carrier concentration) decrease (increase) with an increase of annealing temperature which implies that high temperature annealing could improve the crystal quality and thereby reduce the grain boundary scattering for electron transport. Our results represent a meaningful step toward fabrication of high quality cubic MgZnO thin films use in UVC region.

ZnO nanorod arrays (NRs) are successfully synthesized on CuO thin film by hydrothermal method. The result of scanning electron microscopy demonstrates that the ZnO NRs produce great changes on morphology after deposited on CuO thin film. The current–voltage measurement of ZnO NRs/CuO film heterostructures show an evident rectifying behavior. Furthermore, the photocatalytic activity is investigated by degradation of methyl orange dye. It is found that compared with ZnO NRs, ZnO NRs/CuO film heterostructures display a better photocatalytic activity.

An empirical map of martensitic transformation temperatures versus average valence electrons per atom (e v/a) and valence electron concentration (c v) was developed in order to design ZrCu-based shape memory alloys (SMAs). The martensitic transformation temperatures of about 40 different alloys (Ni, Co, Hf, Ag, Ti, Al, Cr, etc.), covering nearly all possible replacements of Zr or Cu, are exhibited. The relationship between transformation temperature and cv or electron density (n) was determined. The results indicate that the transformation temperatures of ZrCu-based alloys gradually decrease until reaching an inflection point at c v = 0.218, above which the transformation temperatures go down. A linear dependence of the transformation temperatures of ZrCu-based alloys on the electron density is revealed by data-fitting. Under the guidance of these contour maps describing transformation temperatures and thermal hysteresis, a series of ZrCu-based alloys that can function under different conditions can be designed.

The zero-bias resistance area (R0A) product is a primary figure-of-merit of infrared detector. The contributions of different dark current to R0A have been analyzed based on a long wavelength infrared type-II InAs/GaSb superlattice p-i-n photodiode. A dark current of 2.052 × 10−4 A cm−2 and a differential resistance-area of 32.314 Ω cm2 at zero bias voltage are achieved with a 100 % cutoff of 12.5 μm at 77 K. The temperature-dependence and bias-dependence of the dark currents are studied experimentally and correlated to the theory. At 77 K, by modeling the different reduced carrier concentration, the dominant mechanism of R0A can be varied from generation-recombination to tunneling.

We report on the investigation of the dark current contributing mechanism by an effective SiO2 passivated layer deposited at low temperatures. In comparison with the unpassivated photodiodes, at 77 K, the dark current density is reduced by one order of magnitude and a maximum zero-bias resistance area product (R0A) of 567 Ω cm2 is achieved by introducing SiO2-passivated layer deposition technology at a lower temperature of 75°C. The temperature-dependence and bias-dependence of the dark current are studied experimentally and correlated to the theory, and then the fitting with experimental results shows good agreement between theory and experiment. The contribution of each dark current mechanism is also identified.

The ZnO nanorod arrays (NRs) have been fabricated on p-type boron-doped diamond (BDD) substrate by hydrothermal method. It was demonstrated that the density and diameter of the ZnO NRs can be effectively controlled by adjusting the reactant concentration. Photocatalytic activity of the fabricated ZnO NRs/p-BDD heterojunction was investigated for the degradation of methyl orange dye and the results indicated that diameter and density of ZnO NRs play a very important role in photocatalytic degradation. Furthermore, the ZnO NRs/p-BDD heterostructure photocatalysts are easily recycled and reused.

A highly sensitive and selective photoinduced electron transfer (PET) fluorescence chemodosimeter L for Cu(2+) detection has been synthesized and characterized. This PET chemosensor composed of a butano-tethered electron-riched phenothiazine (Ptz) donor and acridine orange (AO) signalling element. Based on the Cu(2+)-promoted oxidation of Ptz donor, the signalling element AO showed a unique fluorescent turn-on properties, which led to a highly Cu(2+)-specific fluorescent chemodosimeter. A fluorescent enhancement factor over 8-fold can be reached by fully blocking the PET channel with a detection limit down to the 10(-7) M range. Meanwhile, the reversibility of the chemodosimeter L can be realized by the addition of L-cysteine.

Human height is a complex genetic trait with high heritability but discovery efforts in Asian populations are limited. We carried out a meta-analysis of genome-wide association studies (GWAS) for height in 6,534 subjects with in silico replication of 1,881 subjects in Han Chinese. We identified three novel loci reaching the genome-wide significance threshold (P5 × 10(-8)), which mapped in or near ZNF638 (rs12612930, P = 2.02 × 10(-10)), MAML2 (rs11021504, P = 7.81 × 10(-9)), and C18orf12 (rs11082671, P = 1.87 × 10(-8)). We also confirmed two loci previously reported in European populations including CS (rs3816804, P = 2.63 × 10(-9)) and CYP19A1 (rs3751599, P = 4.80 × 10(-10)). In addition, we provided evidence supporting 35 SNPs identified by previous GWAS (P0.05). Our study provides new insights into the genetic determination of biological regulation of human height.

Zinc Oxide (ZnO) nanostructures have been grown by electrochemical deposition on the indium-tin oxide (ITO) substrates. The influences and mechanism of pre-treatment of ITO on the morphology, density and size of ZnO nanostructures have been studied. Hexagonal dumbbell-like shape of ZnO bipods have been obtained because of the absence of nucleation sites on the unetched ITO substrate. An ITO etching process in dilute HCl results in the instantaneous and high density nucleation process, which was introduced to reduce the system energy and increase the growth density of ZnO nanostructures. Therefore, well-defined hexagonal and dense ZnO nanorods array are deposited on the etched ITO surface.

Individuals with favorable levels of readily measured cardiovascular disease (CVD) risk factors (low risk, LR) experience low long-term rates of CVD mortality and greater longevity. The purpose of the current study was to compare nutrient/food intakes of LR participants with participants not LR in the INTERMAP study.Men and women (40-59 years) from 17 population samples in four countries (China, Japan, UK, US) provided four 24-h dietary recalls and two timed 24-h urine collections. LR was defined as meeting all of the following CVD risk criteria: systolic/diastolic blood pressure (BP) ≤ 120/ ≤ 80 mmHg; no drug treatment for high BP, hyperlipidemia, or CVD; non-smoking; BMI25.0 kg/m(2) (US, UK) or23.0 kg/m(2) (China, Japan); alcohol consumption26.0 g/day (men)/13.0 g/day (women); and no history of diabetes or CVD. Multivariate logistic regression was used to examine associations of nutrient/food intakes with LR.LR individuals reported higher intake of vegetable protein, fiber, magnesium, non-heme iron, potassium; lower energy intake; lower intake of cholesterol, saturated fatty acids, animal protein; and lower 24-h urinary sodium compared with individuals not LR. With regard to foods, LR individuals reported higher intake of fruits, vegetables, grains, pasta/rice, fish; lower intakes of meats, processed meats, high-fat dairy, and sugar-sweetened beverages than individuals not LR.Lower energy intake and differential intake of multiple specific nutrients and foods are characteristic of individuals at low risk for developing CVD. Identification of dietary habits associated with LR is important for further development of public health efforts aimed at reduction/prevention of CVD.

Metal-assisted chemical etching (MacEtch) of semiconductor materials in HF/H2O2 solution using noble-metal particles as catalysts has gained much attention in the past few years due to its unique properties. In this work, nanoscale Ag particles were deposited on (100) and (111) surfaces of polished p-Si wafers through the silver-mirror reaction. Subsequently these wafers were etched in 1:1:1 (v:v:v) HF(49%):H2O2(30%):EtOH solution at ambient temperature and pressure for 12 h, producing a number of different quasi-ordered silicon micro/nanostructures. The resulting surface-modified wafers exhibited mixed micro- and nanostructures that are an inherent feature of the etch process; for example, steps appear on the sidewalls of crystallographically defined nanopores, because the catalytic Ag nanoparticles are convected as they transit the developing pore during the etching process. The resulting materials exhibited much reduced reflectivity, reaching a maximum of 3.7× reduction near 330 nm, which renders them of interest in potential applications such as back-reflector templates for deposition of thin-film solar cell materials.

The effect of strain accumulation in the InAs/InxGa1−xAs quantum dots (QDs) system was studied in this work. It was found that strain in the InxGa1−xAs layer accumulation in the QD layer. This effect resulted in a dramatic reduction of growth mode transition thickness of the QD layer. For InAs/In0.25Ga0.75As QDs, critical thickness is measured to be as low as 1.08 ML. The experimental results in this work highlight the importance of strain accumulation in the design and fabrication of QD-based devices with metamorphic buffer layer involved.

A method of suppressing the multimodal size distribution of InAs/GaAs quantum dots (QDs) using molecular beam epitaxy through flattening the substrate surface is reported in this work. It is found that the surface roughness plays an important role in the growth of QDs through continuous surface evolution (SEQDs). SEQDs are the main components of small QD ensemble in QDs with multimodal size distribution. It is suggested that most of the SEQDs are very likely to nucleate during the growth interruption rather than during the deposition. The growth of QDs on a smoother surface has largely reduced the density of SEQDs. The photoluminescence line width of uniform QDs is found to be only 17 meV at a low temperature.

To examine the associations between body mass index (BMI), waist circumference (WC) and risk of atrial fibrillation (AF) in Chinese adults.A cross-sectional study was conducted to explore the association between obesity and atrial fibrillation among 18,615 Chinese (10,370 females) aged 35 years and above in 2004. AF was defined by electrocardiography and history. Obesity was classified by BMI and WC, including overweight (BMI: 24.0-27.9 kg m(-2); WC: 85.0-94.9 cm for men and 80.0-89.9 cm for women) and obesity (BMI:or = 28.0 kg m(-2); WC:or = 95 cm for men andor = 90 cm for women), according to the Chinese Guidelines on Prevention and Treatment of Obesity in Adults. Multivariable logistic regression was used to analyze the association between obesity and AF.Age- and sex-adjusted prevalence of AF (n=194) was higher with increased BMI, with 0.9% for normal, 1.1% for overweight and 1.6% for obese (P(trend)0.01) Chinese. Compared with normal BMI, multivariable-adjusted odds ratios (ORs) were 1.2 (95% confidence interval (CI): 0.8-1.7) for overweight BMI and 1.8 (95% CI: 1.2-2.8) for obese BMI (P(trend)0.01). After excluding known secondary AF (valvular, postoperative and hyperthyroid) and unclassified AF, the corresponding multivariable-adjusted ORs were 1.4 (95% CI: 0.9-2.2) and 2.2 (95% CI: 1.3-3.7) (P (trend)0.01). The same trends were observed for WC. Multivariable-adjusted OR was 2.6 (95% CI: 1.4-4.6) for participants with both BMI and WC obesity and 1.7 (95% CI: 1.0-2.9) for participants with both BMI and WC overweight in comparison with those with both BMI and WC in the normal range.Obesity, either defined by BMI or WC, was significantly associated with AF among middle-aged and elderly Chinese.

A series of BaTiO3 fiber and nanopowder unfilled and filled interpenetrating polymer networks (IPNs) composed of polyurethane (PU) and unsaturated polyester resin (UP) are prepared by simultaneous polymerization process. The effect of PU/UP component ratios, the types and amounts of BaTiO3 filled, the polarization treatment to filled IPNs, on the damping properties are investigated by dynamic mechanical thermal analyzer (DMTA). The morphology and microstructures of unfilled and filled IPNs are examined by transmission electron microscope (TEM). The dielectric loss and dielectric constant at different temperatures are studied by AC impedance analyzer. Moreover, the relationship between damping and dielectric properties is discussed in terms of dielectric constant and dielectric loss measured. The results show that the PU/UP component ratios in IPNs, the types of filler, and the amount of nanopowder added all affect the damping behaviors and degree of phase separation of unfilled and filled IPNs. Through polarization treatment, the filled IPNs exhibit synergistic action in systems caused by elastomeric damping mechanism, interfacial frictional damping mechanism and piezoelectric damping mechanisms. The maximum value of E″ of filled IPNs with 70% BaTiO3 increase above 100 MPa and the temperature ranges of tan δ > 0.3 is higher than 100°C compared with unfilled IPNs. Moreover, the maximum value of E″ and the temperature ranges of tan δ > 0.3 increases dramatically after polarizing process. The dielectric properties and its relation with damping properties studies reveal that the temperature ranges exhibit excellent consistency of maximum dielectric loss and dielectric constant with damping loss factor.

PtSi/strained Si1−xGex (x=0, 0.2, and 0.25) Schottky-barrier diodes (SBD) with extended cutoff wavelengths have been demonstrated by combining pulsed laser deposition (PLD) and molecular beam epitaxy (MBE). Pt was deposited by PLD on the Si1−xGex alloys with a thin Si sacrificial cap layer fabricated by MBE. By the reaction of deposited Pt film on Si, a sacrificial cap layer silicide SBD has been fabricated. Auger electron depth profiling was performed on the films before and after in vacuo annealing to study the redistribution of composition in the reactions. High-resolution transmission electron microscopy was used to investigate the interface structure. We have found that Pt reacts mainly with Si to form silicides at 350 °C, leaving some Ge to segregate at the surface. With annealing at 600 °C for 3 min the interface of PtSi/Si1−xGex is smooth. Since lowered-barrier-height silicide SBD are desirable for obtaining longer cutoff wavelength Si-based infrared detectors, the Schottky barrier heights of the PtSi/strained Si1−xGex SBDs with smooth interfaces were substantially lower than those of PtSi/Si SBDs, i.e., decreased with increasing Ge fraction, allowing for tuning of the SBDs cutoff wavelength. At 293 K, the ideality factor has been found to be 2.00 and 1.32 for PtSi/Si0.80Ge0.20 and PtSi/Si0.75Ge0.25 diodes, respectively. We have shown that high quantum efficiency and near-ideal dark current can be obtained in the film of PtSi/strained Si1−xGex with an excellent interface fabricated by MBE and PLD, after annealing at 600 °C for 3 min.

The aim of this report is to describe INTERMAP standardized procedures for assessing dietary intake of 4680 individuals from 17 population samples in China, Japan, UK and USA: Based on a common Protocol and Manuals of Operations, standardized collection by centrally trained certified staff of four 24 h dietary recalls, two timed 24-h urines, two 7-day histories of daily alcohol intake per participant; tape recording of all dietary interviews, and use of multiple methods for ongoing quality control of dietary data collection and processing (local, national, and international); one central laboratory for urine analyses; review, update, expansion of available databases for four countries to produce comparable data on 76 nutrients for all reported foods; use of these databases at international coordinating centres to compute nutrient composition. Chinese participants reported 2257 foods; Japanese, 2931; and UK, 3963. In US, use was made of 17,000 food items in the online automated Nutrition Data System. Average time/recall ranged from 22 min for China to 31 min for UK. Among indicators of dietary data quality, coding error rates (from recoding 10% random samples of recalls) were 2.3% for China, 1.4% for Japan, and UK; an analogous US procedure (re-entry of recalls into computer from tape recordings) also yielded low discrepancy rates. Average scores on assessment of taped dietary interviews were high, 40.4 (Japan) to 45.3 (China) (highest possible score: 48); correlations between urinary and dietary nutrient values--similar for men and women--were, for all 4680 participants, 0.51 for total protein, range across countries 0.40-0.52; 0.55 for potassium, range 0.30-0.58; 0.42 for sodium, range 0.33-0.46. The updated dietary databases are valuable international resources. Dietary quality control procedures yielded data generally indicative of high quality performance in the four countries. These procedures were time consuming. Ongoing recoding of random samples of recalls is deemed essential. Use of tape recorded dietary interviews contributed to quality control, despite feasibility problems, deemed remediable by protocol modification. For quality assessment, use of correlation data on dietary and urinary nutrient values yielded meaningful findings, including evidence of special difficulties in assessing sodium intake by dietary methods.

A series of Zn:Fe:LiNbO3 crystals were prepared by the Czochralski technique with 0.015 wt. % Fe2O3 content and various concentrations of ZnO. The ultraviolet-visible absorption spectra and the infrared absorption spectra of the Zn:Fe:LiNbO3 crystals were detected in order to investigate their defect structure. Their optical damage resistance was characterized by the photoinduced birefringence change and transmission facula distortion method. The optical damage resistance of the Zn:Fe:LiNbO3 crystals increases remarkably when the concentration of ZnO is over its threshold concentration (more than 6.0 mol. %). The effects of defects on the optical damage resistance of the Zn:Fe:LiNbO3 crystals are discussed in detail.

Lead zirconate titanate [Pb(ZrxTi1−x)O3 (PZT)] powders and ferroelectric thin films with a composition near the morphotropic phase boundary [Pb(Zr0.52Ti0.48)O3] were prepared by a modified sol-gel process using zirconium oxynitrate-2-hydrate as the zirconium source and ethylene glycol as solvent. The precursor solution was prepared from lead acetate-3-hydrate, tetrabutyl titanate, and zirconium oxynitrate-2-hydrate. Perovskite PZT powders were obtained after sintering at 450 °C for 2 h. Films rapid-thermally annealed at 650 °C for 1 min formed well-crystallized perovskite.Microstructures of these films indicated the presence of nano-sized grains (∼50 nm). The remnant polarization was 28.5 μC/cm2, and the coercive field was 39.8 kV/cm. Ferroelectric polarization fatigue test of In/PZT/Pt/Ti/SiO2/Si showed a high fatigue resistance up to 3 × 1010 cycles before Pr decreased by 50%.

An improved type of elliptical jacket polarization maintaining fiber was developed by using a modified chemical vapor deposition method with special treatment. Different from conventional elliptical jacket, the shape of the stress jacket was transmuted. The cross-section of fiber consists of 5 layers: substrate, outer cladding, stress jacket, inner cladding and core. The cross sectional component distribution was investigated by electron probe microscopy and energy dispersive spectrum. The finite element method was used to calculate the stress birefringence. Based on the analyses of the microstructure, the technological process is improved. The temperature cycling test of the fiber wound into gyroscope coils was performed. The results show that the fiber possesses superior performance at high and low temperatures compared with other fibers. The high homogeneity is achieved by well-controlled modified chemical vapor deposition process. A homogeneous length of 8 km fiber is obtained. With advantages in homogeneity and length, the fiber has great potential in applications such as fiber gyroscopes, fiber hydrophone and other optical fiber sensors.

Background The lipid-lowering treatment goal attainment rate is lower for women than for men among Chinese patients, but the reasons for this disparity have not been fully explored yet. Objectives To elucidate the potential factors and the significance of their contributions towards the observed discrepancy in lipid-lowering treatment goal attainment rates between Chinese women and men. Methods We used data from 1808 patients from 21 tertiary and 6 secondary hospitals in China who received and maintained statin therapy treatment for at least 2 months. Lipid-lowering treatment goal attainment was defined as low-density lipoprotein cholesterol (LDL- C) reaching the treatment targets recommended by the Chinese Guidelines on Prevention and Control of Dyslipidemia in Adults. Logistic Regression was used to explore possible factors associated with gender disparity in goal attainment rates, and to what extent each factor contributes. Results A total of 674 women and 1134 men were enrolled in the study. Women had a significantly lower LDL-C goal attainment rate than that of men (46.0% vs 53.8%, P = 0.002), particularly in high and very high CVD risk groups. Among high and very high risk patients, approximately 35%, 7%, 5%, and 5% of gender disparity in LDL-C goal attainment rate was attributable to the gender difference in baseline LDL-C level, cardiovascular co-morbidities and associated risk factors, socioeconomic status, and the dosage of statin treatment, respectively. Approximately 50% of the gender disparity remained unexplained by these factors. Conclusions Although nearly half of the gender disparity in lipid-lowering treatment goal attainment rate can be explained by the gender differences in baseline lipid level, socioeconomic status, cardiovascular co-morbidities and associated risk factors, and the dosage of statin in high and very high CVD risk patients, the other half of the gender disparity remains unexplained and requires further study to fully understand what other factors are at play.

Inverse associations have been reported of overall vegetable intake to blood pressure (BP); whether such relations prevail for both raw and cooked vegetables has not been examined. Here we report cross-sectional associations of vegetable intakes with BP for 2195 Americans ages 40–59 in the International Study of Macro/Micronutrients and Blood Pressure (INTERMAP) using four standardized multi-pass 24-h dietary recalls and eight BP measurements. Relations to BP of raw and cooked vegetables consumption, and main individual constituents were assessed by multiple linear regression. Intakes of both total raw and total cooked vegetables considered separately were inversely related to BP in multivariate-adjusted models. Estimated average systolic BP differences associated with two s.d. differences in raw vegetable intake (68 g per 1000 kcal) and cooked vegetable intake (92 g per 1000 kcal) were −1.9 mm Hg (95% confidence interval (CI): −3.1, −0.8; P=0.001) and −1.3 mm Hg (95% CI: −2.5, −0.2; P=0.03) without body mass index (BMI) in the full model; −1.3 mm Hg (95% CI: −2.4, −0.2; P=0.02) and −0.9 mm Hg (95% CI: −2.0, 0.2; P=0.1) with additional adjustment for BMI. Among commonly consumed individual raw vegetables, tomatoes, carrots, and scallions related significantly inversely to BP. Among commonly eaten cooked vegetables, tomatoes, peas, celery, and scallions related significantly inversely to BP.

The morphology and transition thickness (t c) for InAs quantum dots (QDs) grown on GaAs (311) B and (100) substrates were investigated. The morphology varies with the composition of buffer layer and substrate orientation. Andt cdecreased when the thin InGaAs was used as a buffer layer instead of the GaAs layer on (311) B substrates. For InAs/(In)GaAs QDs grown on high miller index surfaces, both the morphology andt ccan be influenced by the interfacial bonds configuration. This indicates that buffer layer design with appropriate interfacial bonds provides an approach to adjust the morphologies of QDs grown on high miller surfaces.

Metal-based silicides on silicon substrates are a widely used material system for infrared detection. PtSi/p-Si infrared Schottky barrier detectors (IRSBD) have become one of the most successful photoemisive infrared detectors. Till now, most of the efforts have been focused on the design of two dimensional PtSi-SBD arrays for the infrared (IR) camera. In this paper, we discussed the formation conditions of PtSi. Qualities are compared for PtSi films prepared at different conditions including different annealing sequences, annealing time, film thickness, and annealing ambient using pulsed laser deposition on various temperature substrates. Film structures and compositions, phase's formation using different processes are analyzed. By studying the kinetics of PtSi formation during various annealing processing, preferable preparing conditions are proposed to form the continuous PtSi ultra-thin film on Si substrate by PLD.