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Combination therapy with pegylated interferon (PEG-IFN) and nucleos(t)ide analogues (NAs) can enhance hepatitis B surface antigen (HBsAg) clearance. However, the specific treatment strategy and the patients who would benefit the most are unclear. Therefore, we assessed the HBsAg loss rate of add-on PEG-IFN and explored the factors associated with HBsAg loss in chronic hepatitis B (CHB) patients. This was a real-world cohort study of adults with CHB. Hepatitis B e antigen (HBeAg)-negative NAs-treated patients with baseline HBsAg ≤1500 IU/ml and HBV DNA the lower limit of detection, or 100 IU/ml, received 48 weeks of add-on PEG-IFN. The primary outcome of the study was the rate of HBsAg loss at 48 weeks of combination treatment. Using multivariable logistic regression analysis, we determined factors associated with HBsAg loss. HBsAg loss in 2579 patients (mean age: 41.2 years; 80.9% male) was 36.7% (947 patients) at 48 weeks. HBsAg loss was highest in patients from south-central and southwestern China (40.0%). Factors independently associated with HBsAg loss included: increasing age (odds ratio = 0.961); being male (0.543); baseline HBsAg level (0.216); HBsAg decrease at 12 weeks (between 0.5 and 1.0 log

In recent years, the research on topological materials, including topological insulator and topological semimetal, has received a lot of attention in condensed matter physics. HgCdTe, widely used in infrared detection, also holds huge potential in this field. It has been reported that the strained thin Hg0.865Cd0.135Te can realize topological insulator phase by using a CdZnTe substrate. However, the stress caused by changing substrate has great limitations. For example, the stress cannot be changed once the sample has been grown. Hence, we try to use a piezoceramics (PZT) instead to implement the stress and control the properties of HgCdTe. The main purpose of our experiment is to verify its validity. As is well known, the band structure of Hg1–xCdxTe can be precisely controlled by changing the content of Cd. When x lies between 0 and 0.165, HgCdTe features an inverted band structure, which is the premise of realizing topological phase. In this work, an inversion layer is induced on a single crystal grown HgCdTe bulk material by anodic oxidation, whose content of Cd is confirmed to be 0.149 by using XRD. Then the sample is thinned and attached to a PZT, which the tuning of stress is realized by applying a voltage to. Ohmic contacts are realized by indium in van der Pauw configuration. All measurements are carried out by using an Oxford Instruments 4He cryostat with magnetic field applied perpendicularly to the sample plane. At 1.5 K and zero voltage, an evident SdH oscillation is observed. By fitting the linear relationship between filling factor and the reciprocal of magnetic field, the concentration is obtained to be \begin{document}${n_{\rm{s}}} = 1.25 \times {10^{16}}\;{{\rm{m}}^{ - 2}}$\end{document}. Subsequently, we scan the voltage from 200 V to –200 V continuously in different magnetic fields. Two phenomena with different characteristics are observed. It is found that the resistance changes linearly with stress at zero field while an SdH oscillation-like behavior occurs at high field. We attribute such a difference to the existence of two conductive channels: one is the bulk material and the other is the two-dimensional electron gas. It is also noteworthy that the topological phase in our sample cannot be determined because the quantum Hall conductance is polluted by the conductance of bulk material. In conclusion, our results show that it is an effective way to use the PZT to tune the stress and this method can also be applied to the research of other materials.

Pb(Zr0.5Ti0.5)O3/CoFe2O4 0-3 thick composite films with various phase composition ratios were deposited on LaNiO3-coated silicon substrates by chemical solution deposition. X-ray diffraction confirmed the coexistence of Pb(Zr0.5Ti0.5)O3 and CoFe2O4 without other impurity phases. Scanning electron microscope revealed that these composite films are crack-free and CoFe2O4 nanoparticles are well dispersed in Pb(Zr0.5Ti0.5)O3 matrix. Our data indicate that the magnetic, dielectric and ferroelectric properties are strongly dependent on the phase composition ratios. Variation in dielectric constant induced by an applied magnetic field demonstrates the expected magnetodielectric effect. The great effect of magnetic field on the ferroelectric loops supports the desired magnetoelectric coupling between Pb(Zr0.5Ti0.5)O3 and CoFe2O4 phases.

Some results on the microstructure controlling and characterization of ferroelectric thin films for uncooled infrared detections are presented. Several novel technologies have been developed to control the microstructures, e.g., grain size, grain shape, and the texture of BST, PZT thin films as well as to fabricate PZT thin films at low temperature. 256 × 1 pixels infrared detector has been prepared and used to realize infrared thermal image. A highly self-polarization in PMNT relaxor films has been observed. A novel readout method with infrared-visible transition mechanism is also discussed.

A new type of incidence-angle-variable infrared spectroscopicellipsometer working in the 2100–10 000 wave number range has been designed and constructed. For the system, the analyzer and polarizer were driven by two microstepping motors having hollow shafts and rotating synchronously with a speed ratio of 2:1, i.e., A=2P. The incidence angle can be varied from 30° to 90° with an accuracy of 0.01°. The doubled Fourier transforms as both functions of the wave number and the azimuthal angles of the polarizer and analyzer were carried out and integrated in the system. Two sets of ellipsometric parameters measured in the experiment have been used to test the data self-consistency of the system. In data reduction, the error arising from the slight anisotropy of the stray light was corrected. In application, the complex dielectric function of the Au film was measured with a data accuracy better that 1% in the entire spectral range.

Quasiperiodic Ba0.9Sr0.1TiO3 (BST) multilayers have been fabricated on SrTiO3 substrates by using chemical solutions containing polyethylene glycol (PEG), and effect of PEG content on optical properties of the BST multilayers have been investigated. Each multilayer with a single perovskite phase displays a layered structure consisting of dense and porous BST layers. It is found that the central wavelength of the reflection-band for BST multilayers shifts to longer wavelength with increasing the PEG concentration within a given polymer amount range. With the same numbers of period and processing condition, the BST multilayers derived from chemical solutions containing PEG additives with a relative molar amount of 0.5, exhibit the highest optical reflectivities.

The magnetic properties of Ni-doped monolayer MoS2 are investigated using the density function theory. The results show that two Ni-doped systems of the nearest-neighbor configuration are ferromagnetic. The p–d hybridization between the Ni dopant and its neighboring S atoms results in the splitting of energy levels near the Fermi energy. These results suggest the p–d hybridization mechanism for the magnetism of the Ni-doped MoS2 monolayer. The magnetic moment disappears with increasing Ni–Ni distance. Our studies predict the nearest two-Ni-doped MoS2 monolayers to be candidates for thin dilute magnetic semiconductors. Moreover, the formation energy calculations indicate that it would be easier to incorporate Ni atoms into a S-rich MoS2 monolayer in the experiment.

The infrared absorption spectra have been measured at temperatures from 4.2 to 300 K for thin bulk samples of Hg1−xCdxTe with compositions, x, from 0.170 to 0.443 with thicknesses smaller than 10 μm. The spectral range of the investigations includes the exponential absorption edges and intrinsic absorption spectra determined by electron transitions from the valence band to the conduction band. From the measured absorption spectra, the energy‐band gap was determined by the photon energy at the absorption transition point between the Urbach exponential region and the Kane region. The data were fitted by a calculation of the intrinsic optical transition using Kane’s theory. The dependence of the energy‐band gap on composition and temperature was determined in the alloy composition range from x=0 to 0.443 and for x=1, for temperatures from T=4.2 to 300 K. The absorption coefficient, αg, at the band‐gap energy versus composition and temperature, and the exponential rule satisfied by the absorption edge are als...

Mn 1.56 Co 0.96 Ni 0.48 O 4 films with spinel structure for infrared detection are prepared on Al 2 O 3 substrate by chemical solution deposition method. The resistance vs temperature (R-T) characteristics at 130~304 K temperature range and infrared transmission spectrum (1-10 m) are measured and temperature coefficients of resistance (TCR) are calculated. The conduction process can be explained well by hopping conduction. At low temperature nearest neighbor hopping (NNH) mechanism fits the data well, while at high temperature, variable range hopping (VRH) mechanism dominates the system, and this transition temperature is at about 200 K. The value of TCR is about -3.73% K -1 at 300 K. Mn 1.56 Co 0.96 Ni 0.48 O 4 films exhibit a strong absorption around 2 m which is considered to be corresponding to the gap of energy bands showed by infrared transmission spectrum. The band gap obtained from the transmission spectrum data using the Tauc’s law is ~0.567 eV. Keywords: spinel, Infrared detection, Hopping conduction, Negative temperature coefficients, transition metal oxides.

Hybrid barium strontium titanate (BST) ferroelctric detectors still provide the basis for the majority of uncooled infrared systems being produced today. Considering the complexity of the hybrid BST detector fabrication process, monolithic BST thin-film dielectric bolometers allure the researchers. For the micro-bridge thermal isolation structure, the performances of single pixel of BST thin-film dielectric bolometer mode of uncooled infrared focal plane arrays (IRFPA) are computed by thermal diffusion equation.

The BaTiO3 and Mn:BaTiO3 thin films were fabricated on fused quartz and Si(111) substrates by a sol-gel method. The crystal structures of the samples were characterized by x-ray diffraction. It is shown that the samples are both polycrystalline thin films and possess cubic structure. The Mn-doping has no obvious effect on the crystal structure. The optical properties of the thin films were studied by transmitted spectrum technique or by spectroscopic ellipsometry depending on the substrate used. The transmitted spectrum shows that the absorption edge of the Mn-doping films has red shift compared with the undoping films. The energy gaps calculated from the transmitted spectrum are 3.68 and 3.39eV for undoping and Mn-doping samples, respectively. The results of spectroscopic ellipsometry shows that the refractive index of the Mn:BaTiO3 thin film is bigger than that of the BaTiO3 thin film. Which the change of energy gap and refractive index caused by Mn-doping can be explained by the Sellmeier Oscillator model.© (2004) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

The structure and ferroelectric properties of Bi3.25 La 0.75Ti3O12 (BLT) and Bi3.25 Nd0.75Ti3O12 (BNT) thin films deposited on (111)Pt/Ti/SiO2/Si substrates using a metalorganic decomposition (MOD) method were investigated. Both the films were polycrystalline structure with the single bismuth-layered phase. The BNT film showed the (117) random orientation, while the BLT film displayed (00l )-preferential orientation. The BNT film showed a larger remnant polarization (~13.8μC/cm2) than the BLT film (~3.5μC/cm2), while both films displayed almost the same value of coercive field. The BNT film had the larger dielectric constant and a litter larger dissipation factor than the BLT film. The superior ferroelectricity of the BNT film was mainly attributed to its (117) random orientation. Furthermore, the BNT film displayed good fatigue endurance up to 109 switching cycles, indicating it was a useful candidate for integrated device applications.© (2004) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

92%Pb(Mg1/3Nb2/3)O3-8%PbTiO3 (PMNT) thin films on Pt/TiO2/SiO2/Si substrates with and without a LaNiO3 (LNO) buffered layer have been prepared using a sol-gel method. Structures and electrical properties of these two films have been investigated and compared. Highly (111)-oriented PMNT thin films with some amounts of pyrochlore phase are obtained on bare Pt electrodes. On the contrary, (100)-oriented PMNT thin films with pure perovskite phase are formed on Pt electrodes with a LNO buffered layer. Electrical properties of the PMNT thin films are highly improved by using the buffered layer LNO. It is found that the remanent polarization (P r) and the dielectric constant for the PMNT film with a LNO buffered layer are larger than that for the film without a LNO buffered layer.© (2004) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

2 mol% Lanthanum doped lead zirconate titanate Pb(Zr 0.4 Ti 0.6 )O 3 ferroelectric thin film were successfully deposited by a modified sol-gel method on(111) Pt/Ti/SiO 2 /Si(100) substrate, the effect of heat-treatment on the properties of microstructure and ferroelectric was investigated. It is shown that deposited on (111)Pt lead to (111) preferred orie ntation. The PLZT thin film annealing at 700 0 C show good ferroelctric properties with a large remnant polarization of 40µ C/cm 2 , a spontaneous polarization of 75.7µ C/cm 2 , and a coercive field of 112kV/cm under an electric field of 650kV/cm. The dielectric constant increased with annealing temperature. Keywords: ferroelectric thin films; sol-gel; remnant polarization ; coercive field; 1. INTRODUCTION Lead-based ferroelectric thin film , e.g., PbTiO 3 (PT), Pb(Zr x Ti 1-x )O3 (PZT), Pb 1-x La x (Zr y Ti 1-y )O 3 , have been show to be of major technological interests due to their promising potential for applications such as pyroelectric detectors, piezoelectric vibrators, electric-optical devices and nonvolatile random access memories. Many processing routes for PZT thin film, including laser ablation[1], rf spu ttering[2], CVD and solution deposition methods, have been reported. Among those methods, Sol-gel processing is a very attractive methods, it has many advantages such as easily controlling stoichiometry and microstructure, relatively lo w processing temperature and quite simple processing. The substrate heterolayer structures usually used are based on Pt/Ti/SiO

Highly (100)-oriented LaNiO3-δ (LNO) thin film were grown on n-type Si(100) at substrate temperature 200°C with 40% oxygen partial pressure. The as-deposited LNO films are metallic and have a resistivity of ~9×10-4 mΩcm at room temperature (RT) and can be used as the bottom electrode for the fabrication of integrated ferroelectric capacitors on Si. A post-annealing process can decrease the RT resistivity to ~3×10-4 Ωcm at 700°C and yield crack at 800°C.© (2004) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

A revised method to evaluate parameters of solar cell from current-voltage characteristics,under illuminated or non-illuminated conditions,w as described. The series resistance( R s),the shunt resistance( R sh),the ideality factor( n),and the reverse saturation current density( J0) were extracted using the two diode circuit model from selected regions of the J-V curves. Using the presented model,more parameters w ith higher fitted precision have been extracted from experimental J-V curves of a CdS / CdTe thin film solar cell than using a single diode circuit one.

CdS thin films were deposited on the substrate at temperature of 300 ℃ by magnetron sputtering. The deposited films were annealed at temperature of 370℃,380 ℃ and 390 ℃,respectively,in either atmosphere of dry air or a mixture of CdCl2and dry air. The morphology,structure and optical properties before and after thermal annealing were investigated. The results show that for samples annealed in dry air,the variations of grain size,surface roughness and visible light transmittance with annealing temperature are not obvious,while the optical band gap increases with temperature increasing. Annealed in the mixture of CdCl2and dry air,recrystallization and grain growth in the samples are significant. Surface roughness increases with temperature increasing,on the contrary,visible light transmittance and optical band gap decreases. These phenomena are the results of changes in the temperature of recrystallization and doping concentration in the band tail states at different annealing atmosphere.