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We propose a comprehensive point spread function (PSF) degradation model, which considers multiple factors consisting of degradation of specimen retardant sampling and polarization angularly anamorphic sampling, to indicate the image degradation characteristics of polarization imaging systems. First, a one-layer optical coherence tomography (OCT) model was established to express the retardancy of medium-loading specimens. Then, a PSF degradation model of angularly anamorphic polarization sampling was deduced through the retrieval of Stokes parameters. Finally, maximum a posteriori probability (MAP) was adopted to assess the distribution of the proposed model. Hypothesis testing using actual data and numerical simulations demonstrated that the error of the system followed an asymmetric generalized Gaussian distribution (AGGD). Finite-difference time-domain (FDTD) simulation results and an actual imaging experiment demonstrate the consistency of the proposed model and the degradation characteristics of the PSF, which provide support for the improved accuracy and enhanced image quality of the optical field retrieval of nanoparticles.

The LiFePO 4 /C (LFP/C) composite as a cathode material for lithium-ion battery was synthesized by solid-state reaction under vacuum sintering condition (20–5 Pa). The effects of vacuum sintering temperature and time on the phase composition, morphological structure, and electrochemical performance of LFP/C composite were investigated by X-ray diffraction, scanning electron microscopy, galvanostatic charge–discharge cycling test, and electrochemical impedance spectroscopy. The synthetic LFP/C composite possessed uniform particle-size distribution with porous architecture upon sintering at 650 °C for 12 h and thus exhibited the highest discharge capacity and best cycle performance. The complete decomposition of citric acid at a suitable temperature under vacuum condition resulted in the formation of porous structure. Compared with atmospheric argon sintering, vacuum sintering method led to the formation of porous architecture, the porous sample showed excellent cycle performance with less than 2% capacity loss after 80 cycles at 0.2 C, and reached the discharge specific capacity of 87.6 mAh g −1 at 10 C rate, these are better than that of atmospheric argon sintering. The LFP/C composite prepared under vacuum sintering also reduced the optimum sintering temperature by nearly 100 °C compared with that prepared under atmospheric argon sintering.

A new method to generate a three-dimensional (3D) nanoscale tetrapod-shaped zinc oxide whisker (NT-ZnOw) with spatial random distribution is proposed, and a corresponding program is developed. A whisker-generating program is combined with finite element method to build a 3D finite element model that can predict the mechanical properties of NT-ZnOw/resin composites. A 3D finite-element unit cell is adopted and subjected to periodic displacement boundary conditions to explore the equivalent mechanical properties of the NT-ZnOw/resin composites. A micromechanics finite element model of the NT-ZnOw reinforced composites containing various volume fractions of NT-ZnOw is also developed. Effects of different volume fractions and aspect ratios of the whisker on the stiffness of the composites are investigated. These parameters can be used in the microscopic prediction and analysis to determine the mechanical properties of whisker-reinforced composites with multivariate and random distribution of the whiskers. The numerical and theoretical predictions are in good concordance.

With the increase of traffic volume, the enlarging tunnel span and the decreasing of surrounding rock integrity, the level of surrounding rock will be lower. This article proposed the calculating method of relative integrity index based on the concept of relative integrity of surrounding rock and established the Fuzzy Comprehensive Evaluation Method for rock classification by analyzing the impact of tunnel span enlargement upon rock stability. It also specified the determination factors, discussed the selection of weight indexes and proposed methods of establishing the qualitative and quantitative subordinate degrees. Based on practices of the expressways of Fuzhou, Xiamen and Zhangzhou, this article made fuzzy comprehensive evaluation of rock classification and fully analyzed the results of the evaluation. Results showed that with the enlargement of tunnel span, levels of surrounding rock would lower accordingly, and that the worse surrounding rock was, the more it would lower.

According to the hypothesis that the tourmaline particle is composed of crystal electric dipoles, the far infrared emission and its vibration frequency of the natural black tourmaline superfine powders were researched. The behavior of the electric dipole in the ground and excitation states was calculated. It was found that there is a relationship between infrared absorption spectra and the microscopic D-value of electric dipole moment. The high far infrared emissivity of tourmaline was ascribed to the coherent light created by stimulated emission between different excitation states of electric dipole.

BiFeO3, LO2a-doped BiFeO3, and (La, Co)-codoped BiFeO3 thin films were fabricated on Pt/Ti/SiO2/Si(111) substrates by chemical solution deposition method. The structural and electrical properties of pure, La-doped, and (La, Co)-codoped BiFeO3 thin films were studied. X-ray diffraction analysis showed that all the films were single perovskite structure. Electrical measurements indicated that the ferroelectric properties of BiFeO3 thin films were significantly improved by La and Co codoping. Well saturated hysteresis characteristic with large remanent polarization (larger than 57 μC/cm2) were observed in Bi0.9La0.1Co0.1Fe0.9O3 thin film.

Mineral black tourmaline powders were heat-treated at different temperatures. Their crystal structure was studied by X-ray diffractometer. Their infrared absorption and emission spectra before and after the heat treatment were analyzed by the Fourier transform infrared spectrometer. The corresponding fine structures were discussed in detail. The results showed that the powders possessed higher infrared emissivity at the band where they showed stronger infrared absorption. However, there is no certain correlation between the peak intensity of infrared absorption and emissivity values at the same frequency. Because of the crystal shrinkage of c-axis, the electronic transitions were stimulated between different energy levels, and the abilities of infrared absorption and emission were enhanced with increasing the temperature of heat treatment.

In the present paper, Laser Raman spectral was used to study the carbon structure of LiFePO4/C positive material. The samples were also been characterized by X-ray diffraction (XRD), scanning electron microscope(SEM), selected area electron diffraction (SEAD) and resistivity test. The result indicated that compared with the sp2/sp3 peak area ratios the I(D)/I(G) ratios are not only more evenly but also exhibited some similar rules. However, the studies indicated that there exist differences of I(D)/ I(G) ratios and sp2/sp3 peak area ratios among different points in the same sample. And compared with the samples using citric acid or sucrose as carbon source, the sample which was synthetized with mixed carbon source (mixed by citric acid and sucrose) exhibited higher I(D)/I(G) ratios and sp2/sp3 peak area ratios. Also, by contrast, the differences of I(D)/I(G) ratios and sp2/sp3 peak area ratios among different points in the same sample are less than the single carbon source samples' datas. In the scanning electron microscopy (sem) and transmission electron microscopy (sem) images, we can observed the uneven distributions of carbon coating of the primary particles and the secondary particles, this may be the main reason for not being uniform of difference data in the same sample. The obvious discreteness will affect the normal use of Raman spectroscopy in these tests.

In order for industrial and mining enterprises to fast detect the quality of fine mineral powders with far infrared emission, a simple testing model was set up according to the relationship between the emission intensity of powders and their surface temperature. The corresponding testing device was designed and assembled into three parts containing Constant Temperature Heating Part, Temperature Measuring Part and Sample Loading Part. By using the tourmaline mineral powders with far infrared emission as the research object and combining Fourier transform infrared spectroscopy, the calibration for the testing device was carried out. The results showed that the far infrared emission intensity of the tourmaline powders with different mining area and particle size could be judged. The testing results exhibited correct values when compared with those from FTIR measurements.

Tourmaline superfine powders with different particle sizes were prepared by grinding, superfine ball milling, and high-speed centrifugation. The powders were characterized by scanning electron microscopy, X-ray diffraction, dynamic contact angle meter and tensiometry, and Fourier transform infrared spectrometry. The results show that tourmaline powders exhibit improved far infrared emission properties as the particle size decreases. The increased surface free energy and proportion of the polar component are considered to play an important role for their properties. The spontaneous polarization is increased, and the dipole moment of tourmaline is stimulated to a high energy level more easily for the chemical bond vibration, so that the energy is apt to emit by transition. In the range of 2000-500 cm(-1), the emissivity values of the samples with D50 size of 2.67 microm and 0.2 microm are 0.973 and 0.991, respectively.

To analyze the effect of passive smoking during different pregnancy term to infant birth weight.155 women which infants were singleton term small-for-gestational-age infant (SGA) -cases and 155 with singleton term non-SGA controls matched by infant sex, infant birthday ( +/-10 days) and maternal age (20 years, 20- 35 years andor = 35 years) were interviewed. Single and multiple analyses were performed by conditional logistic regression.Passive smoking during the second, the third or the whole term of pregnancy was significantly associated with risk of term SGA (P0.05). The odds ratios of these risk factors were 3.07, 2.94 and 3.42 respectively. Passive smoking during the first term of the pregnancy was not associated with risk of term SGA ( P0.05) .Decreasing passive smoking during the second or the third term of pregnancy maybe benefits to lower the risk of term SGA.

To fund out the state of passive smoking of non-smoking women and search for measures of controlling women passive smoking.3500 non-smoking women in Beijing, Shanghai, Chengdu city were interviewed. Analyses were performed by chi2 test Fisher test and ANOVA test.92.7% passive smoking women exposure to ETS at home, 40.8% at workplace. 38.9% exposed to ETS from birthday, and 42.3% from 18 - 30 age. The average exposure time of passive smoking is (1.17 +/- 1.10) hours per day. The proportion of passive-smoking time over 2 hours at home is higher than work place. In passive-smoking group, the proportion of 30 - 50 age group, secondary education, married, merchant/service, principal of units, and manufacture/transport workers were higher than non-smoking group. 97.5% think that passive smoking is harmful to health, and the proportion of thinking passive smoking has severe harm to health in non-passive-smoking group is higher than passive-smoking group. 70.0% open windows when someone smokes around her, but only 16.9% ask the smokers do not smoke around her forwardly. Suppose that someone were smoking around yourself, the consciousness of avoiding passive smoking forwardly in non-passive-smoking group is stronger than passive-smoking group. 95.1% believe the content of smoking-harm propagandized by medium.The main places of controlling passive smoking are the home and the department, commerce, service, and manufacture/ transport workplace. The rate of passive smoking was influenced by the consciousness of the serious level of harms by passive smoking. Propagandizing the serious harm of passive smoking by medium and strengthening the consciousness of avoiding passive smoking were one of feasible measures to lower the rate of smoking and passive smoking.

To investigate the risk factors for lung cancer among women who had never smoked. Methods A 1:2 matched case-control study was carried out. The cases are the no-smoking female patients with the primary lung cancer diagnosed by pathology mothed from hospitals in Beijing, Shanghai and Chengdu between September 2001 and February 2004. One hospital control and one population control matched for age, sex and no-smoking et al., were enrolled. The case and control were interviewed about the exposure information of related factors using the uniform questionnaire. Statistical analysis of single-factor and multivariate conditional Logistic regression were performed to screen the risk factors of lung cancer.During the single-factoranalysis, 28 exposure factors were identified as risk factors for lung cancer. The multivariate conditional Logistic regression show that passive smoking indexor = 50 person * year (OR = 1.77,95% CI, 1.07 - 2.92), consumption of internal organs of animals (OR = 1.85,95% CI, 1.06 - 3.22), and occupational exposure to dust (OR = 2.47,95% CI, 1.21 - 5.03) and bad ventilation in workplace( OR = 4.02,95% CI, 1.74 - 9.29) are risk factors for lung cancer, but consumption of vegetables( OR = 0.26, 95% CI, 0.12 - 0.59), taking vitamins often (OR = 0.53, 95% CI, 0.30 - 0.93), average month income per person after marriedor = 500 yuan ( OR = 0.50, 95% CI, 0.28 - 0.91) and the first procreation occurred between 24 and 30 years old (OR = 0.53, 95% CI, 0.32 - 0.90) are the protective factors for lung cancer. The dose-response were observed between passive smoking and risk rate of lung cancer by trend test.Some factors such as passive smoking, consumption of internal organs of animals, occupational exposure to dust and bad ventilation in workplace can increase the risk of lung cancer for women who had never smoked. Other factors such as consumption of vegetables, taking vitamins, and so on, can reduce the risk of lung cancer for women who had never smoked.