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Alkaline water electrolysis is the most promising approach for the industrial production of green hydrogen. This study investigates the dynamic operational characteristics of an industrial-scale alkaline electrolyzer with a rated hydrogen production of 50 m3/h. Strategies for system control and equipment improvement in dynamic-mode alkaline electrolytic hydrogen production are discussed. The electrolyzer can operate over a 30%–100% rated power load, thereby facilitating high-purity (>99.5%) H2 production, competitive DC energy efficiency (4.01–4.51 kW h/Nm3 H2, i.e., 73.1%–65.0% LHV), and good gas–liquid fluid balance. A safe H2 content of 2% in O2 (50% LFL) can be guaranteed by adjusting the system pressure. In transient operation, the electrolyzer can realize minute-level power and pressure modulation with high accuracy. The results confirm that the proposed alkaline electrolyzer can absorb highly fluctuating energy output from renewables because of its capability to operate in a dynamic mode.

Nano-polymers (NPs) with non-conjugated moiety emit bright fluorescence when irradiated by ultraviolet lights, which arouses extensive interests since they do not have traditional fluorophores or conjugated moieties. Although the mechanism was put forward in some reports and entitled as “crosslink enhanced emission” (CEE) the oxidation of starting material is also contributable for the enhanced fluorescence according to our researches. However this has been neglected until now. Herein, when aqueous solution of pure polyethyleneimine (PEI) was suffered from heating at 180° in air for 60 min crosslink of PEI molecules took place and produced PEI NPs. It emitted bright blue fluorescence and the quantum yield reached as high as 18.24% while PEI itself possessed none of fluorescence. Infrared, 1H nuclear magnetic resonance and X-ray photoelectron spectra disclosed the oxidation of PEI during the lasting heating. And the image of transmission electron microscope confirmed the production of PEI NPs. When PEI NPs were prepared in the presence of hydrogen peroxide they performed a successive enhancement of fluorescent intensity, which demonstrated the oxidation of PEI contributed a lot for the fluorescent enhancement of PEI NPs. Experimental results also demonstrated that the PEI NPs have a potential application in cellar imaging on account of the lower cytotoxicity and the reactivity to the activated folic acid.

Background: Serum prostate-specific antigen (PSA) is a primary metric for diagnosis and prognosis of prostate cancer (PCa). Exposure to heavy metals, such as lead, cadmium, mercury, and zinc can impact PSA levels in PCa patients. However, it is unclear whether this effect also occurs in men without PCa, which may lead to the overdiagnosis of PCa.Method: Data on a total of 5,089 American men who had never been diagnosed with PCa were obtained from the National Health and Nutrition Examination Survey performed from 2003–2010. The relationship between serum PSA levels (dependent variable) and concentrations of lead (μmol/L), cadmium (nmol/L), and mercury (μmol/L) were investigated with dietary zinc intake being used as a potential modifier or covariate in a weighted linear regression model and a generalized additive model. A series of bootstrapping analyses were performed to evaluate sensitivity and specificity using these models. Results: Regression analyses suggested that, in general, lead, cadmium, or mercury did not show an association with PSA levels, which was consistent with the results of the bootstrapping analyses. However, in a subgroup of participants with a high level of dietary zinc intake (≥14.12 mg/day), a significant positive association between cadmium and serum PSA was identified (1.06, 95% CI, P=0.0268, P for interaction=0.0249).Conclusions: With high-level zinc intake, serum PSA levels may rise in PCa-free men as the exposure to cadmium increases, leading to a potential risk of an overdiagnosis of PCa and unnecessary treatment. Therefore, environmental variables should be factored in the current diagnostic model for PCa that is solely based on PSA measurements. Different criteria for PSA screening are necessary based on geographical variables. Further investigations are needed to uncover the biological and biochemical relationship between zinc, cadmium, and serum PSA levels to more precisely diagnose PCa.

The effect of adding sourdough with lactic acid bacteria (Lactobacillus plantarum M616) on dough quality and the sensory scores, specific volume, crumb firmness, and spread ratio of resultant Chinese steamed bread were studied. The moisture content of crumb and texture characteristics of the Chinese steamed bread with sourdough during storage were analyzed. In this study, 10%, 20%, 30%, and 40% of sourdough addition was investigated. The sourdough starter resulted in significant decrease in the water absorption, development time, stability, and farinograph quality number of the dough. The addition of sourdough improved the quality of Chinese steamed bread such as improving the sensory scores and specific volume, decreasing the crumb firmness, and a lower spread ratio was observed with an increase in the sourdough concentration up to 30%. Sourdough addition delayed a fast decrease in the moisture content of the Chinese steamed bread crumb during storage. The texture profile analysis of the bread crumb indicated that the addition of sourdough improved the quality and delayed the staling speed of Chinese steamed bread during storage. Moreover, inclusion of 30% sourdough produced the best protective effect on product staling.Supported by National Natural Science Foundation of China (31571780), Key Research Project in Higher Education of Henan (18A550002), Zhengzhou Science and Technology Innovation Team Program (121PCXTD518), School Funds of Henan University of Technology (2017QNJH11), and High-level Talent Foundation of Henan University of Technology (2017BS005) Keywords:: Sourdough, Chinese steamed bread, Dough quality, Shelf life, Texture profile analysis

The objective of this study was to predict the potential influence of applying biogas slurry (BS) continuously for several years on soil chemical characteristics. Five kinds of Farmland which have been irrigated using BS respectively for 0, 1, 2, 4, 6 years were chosen as the research objects, and soil characteristics and cabbage growth in the different farmlands were analyzed, so can to provide practical basis for scientific application of BS. The results of the experiment indicated that soil pH value enhanced, soil exchangeable H+ and exchangeable Al3+ descend by applied BS, the acid-alkali balance of soil could been easier keep stable if BS been used for more years; the contents of reductive material(RM), activity reductive material(ARM), and ratio of ARM are all increased with the age added by applied BS, so the redox balance of soil have been broken because of applied BS; Soil water-soluble K+, Na+, Ca2+, Mg2+, SO4 2-, HCO3 −, Cl− were been affected obviously by applied BS, the contents of water-soluble K+, Na+, Cl−, SO4 2- are all increased, and the contents of soil water-soluble Ca2+, Mg2+, HCO3 − are all decreased with the age added by applied BS.

Marine and freshwater fish surimi exhibit a synergistic effect when mixed in a suitable ratio. In this paper, we investigated changing in myofibrillar protein conformation enhance the properties of mixed surimi gels formed by thermal processing. The mixtures of Nemipterus virgatus and Hypophthalmichthys molitrix surimi were prepared (N:H mass ratios of 0:1, 1:0, 3:1, and 1:5) and analyzed during thermal processing. In particular, changes in gel properties, microstructure, and protein conformation during gel formation were studied. The obtained results show that heating increases the fracture constant of the 3:1 and 1:5 surimi mixtures from 143.64 N/m and 68.40 N/m to 442.78 N/m and 320.99 N/m, respectively, and the fracture constant of the 1:0 and 0:1 surimi from 87.07 N/m and 56.71 N/m to 443.18 N/m and 237.42 N/m, respectively. Similarly, the water holding capacities, whiteness values, β-sheet, β-turn, and disulfide bond contents of these two gels increase with increasing processing time at 40 then 90 °C. Meanwhile, nonspecific association, hydrogen bonding, and α-helix contents in the N:H = 3:1 and N:H = 1:5 samples decrease under the effect of thermal processing. Microstructural images show that the network structure of the mixed surimi gel is tighter and more compact than that of the single-component gels. Based on these results, the synergistic effect is induced by the interactions between proteins from different sources in a suitable ratio.

N,O-acetals are important structures found in many bioactive natural products, and this unique organic functional group can serve as a useful synthetic precursor to the unstable N-acylimines. In this paper, a convenient route to synthesize N-carbamoyl-N,O-acetals and N-acyl-N,O-acetals from enecarbamates and enamides in the presence of alcohols as the solvents and nucleophile sources under Bronsted acid conditions was reported. This strategy could be used to prepare various N,O-acetals from a range of enecarbamates and enamides with light alcohols, and the products are obtained in good yields (52–98%).

Ignition delay measurements of gas-phase decalin/air mixtures were performed in a shock tube at temperatures of 950-1395 K, pressures of 1.82×10 to 6.56×10 Pa, and equivalence ratios of 0.5, 1.0, and 2.0. The ignition delay time was determined using the reflected shock wave pressure and CH* emission monitored at the sidewall. The effects of temperature, pressure, and equivalence ratio on the ignition delay time of decalin were investigated systematically. The results show that increasing the temperature or pressure decreases the ignition delay time. Opposite ignition delay dependences on the equivalence ratio were observed for decalin/air at high and low pressures, for the first time. At 15.15×10 Pa, the fuel-rich mixture showed the shortest ignition delay time, and the fuel-lean mixture gave the longest one. However, at 2.02×10 Pa, the fuelrich mixture had the longest ignition delay time. Comparisons of the experimental data with predictions based on the available kinetic mechanism were made; the trends in the experimental data were in good agreement with the predictions under all conditions studied. A sensitivity analysis was performed to obtain insights into the effects of the equivalence ratio on the ignition delay time at low and high pressures. The results show that ignition is mainly controlled by the reaction H+O2=OH+O at 2.02×10 Pa. However, the reactions involving decalin and its corresponding radicals play important roles at 15.15×10 Pa. 836 HE Jiu-Ning et al.: Shock Tube Ignition Delay Measurements of Decalin/Air Mixtures at High Temperatures No.5

Alpha-MnO2, beta-MnO2, gamma-MnO2, and delta-MnO2 catalysts were synthesized by hydrothermal methods, and their catalytic performances towards the oxidation of ethanol were evaluated in detail. The as-synthesized MnO2 catalysts were characterized by N-2 adsorption-desorption measurements, X- ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and H-2 temperature-programmed reduction (H-2-TPR). The alpha-MnO2 catalyst showed the best activity of the catalysts tested for the combustion of ethanol and the trend in the activity of different MnO2 catalysts towards the oxidation of ethanol was of the order alpha-MnO2>delta-MnO2>gamma-MnO2>beta-MnO2. The effect of the crystal phase structure on the activity of the MnO2 catalysts was investigated. The XRD results showed that there were differences in the crystallinities of the alpha-, beta-, gamma-, delta-MnO2 catalysts, but these differences did not have a significant effect on their catalytic performances towards the oxidation of ethanol. The BET surface areas of the alpha-, beta-, gamma-, delta-MnO2 catalysts exhibited similar tendencies to their ethanol oxidation activities, although the results of standardization calculations showed that the surface area was not the main factor affecting their catalytical activities. The XPS results showed that the lattice oxygen concentration played an important role in defining the catalytic performance of the MnO2. The alpha-MnO2 catalyst showed the best reducibility of all of the MnO2 catalysts tested, as determined by H-2-TPR. The excellent performance of alpha-MnO2 was attributed to its higher lattice oxygen concentration and reducibility, which were identified as the main factors affecting the activity of the MnO2 towards the complete oxidation of ethanol.

An experiment was conducted by fertilizer packet burying method to determine the nitrogen release of SCU, PSCU and PCU in the soil during corn and wheat planting period. Results showed that Packet burying method can be used to measure the nitrogen release characteristics of coated controlled release urea in soil. This test method can simulate the nutrient release situation of controlled release fertilizer applied in soil. It plays an important role in fitting fertilizer demand with fertilizer supply during plant growth period as well as improving the precision of controlled release fertilizer using.

The influence of CO(2) content and SO(2) presence on the leaching toxicity of heavy metals in municipal solid waste incinerator (MSWI) fly ash was studied by examining the carbonation reaction of MSWI fly ash with different combinations of simulated incineration flue gases. Compared with raw ash, the leaching solution pH of carbonated ash decreased by almost 1 unit and the leaching concentrations of heavy metals were generally lower, with that of Pb decreasing from 19.45 mg/L (raw ash) to 4.08 mg/L (1# carbonated ash). The presence of SO(2) in the incineration flue gas increased the leaching concentrations of heavy metals from the fly ash to different extents after the carbonation stabilization reaction. The pH of the leaching solution was the main factor influencing the leaching concentrations of heavy metals. The increase in buffer capacity with the pH of carbonated ash caused an increase in heavy metal stability after the carbonation reaction. Accelerated carbonation stabilization of MSWI fly ash could reduce its long-term leaching concentrations (toxicity) of Cu, Pb, Se, and Zn. The leaching concentrations of heavy metals from carbonated ash also likely had better long-term stability than those from raw ash. The presence of SO(2) in the incineration flue gas increased the proportion of exchangeable state species of heavy metals; slightly increased the long-term leaching toxicity of Cu, Pb, Se, and Zn; and reduced the long-term stability of these metals in the fly ash after the carbonation reaction.

A novel inorganic-organic hybrid material, Fe2O(OH)(C5H4-NCOO)SO4 was synthesized via solvothermal route using a reaction of FeCl3 ·6H2O, KCNS, and 4-cyanopyridne in aqueous solution of H2O2 and ethanol at 130 °C for 3 d. The compound crystallized in monoclinic space group P21, with cell parameters a=0.73850(15) nm, b = 0.65100(13) mn, c = 1.0546(2) nm, β = 90.36(3)°, V = 0.50700(18) nm3 and Z = 2. The structure is constructed with inorganic layered [Fe2O(OH) SO4]+ cations linked by organic (C5H4NCOO)− anions. The compound is thermally stable up to approximately 240 °C.

Leachate levels are important to landfill stability and safety. High leachate or water levels often lead to landfill instability, which can cause accidents. Here a case study of a landfill located in a humid region of southern China is presented. Leachate distribution and quality were systematically analyzed, and the effect of leachate level on waste-mass stability was assessed. Boreholes were drilled in the field, samples were analyzed in the laboratory, and a simulation was performed. In addition, the safety and stability of the landfill was evaluated. The leachate level in the landfill was 9-19m, which was higher than the top of the dam crest (8-20m). Leachate accounted for more than 1/4 of the total landfill storage capacity. The contaminant concentration of the leachate samples collected directly from the waste body was very high, with large variation among the samples. The mean concentrations of NH(3)-N, BOD, and COD from the waste body were 5404, 14,136, and 22,691mg/L, nearly 2.7, 2.4, and 1.8 times the mean concentrations in the leachate pond, respectively. Three series of shear strength parameters were used in a slope stability analysis, and a limit equilibrium method was used to calculate the factor of safety (Fs). The analysis showed that Fs could be affected by potential anisotropy in the shear strength of the waste. The minimum values of Fs corresponding to series I were 1.84 and 1.17 for units capital I, Ukrainian and II, respectively. The Fs value of unit II was significantly lower than the safe design value (1.25). In addition, Fs decreased with increase in the normalized height of the leachate level, h/H, where h is the height of the leachate mound and H is the maximum thickness of the landfill. If the h/H values of units I and II are kept below 50% and 40%, respectively, a safe design value of 1.25 for Fs can be guaranteed. Therefore, some measures to prevent risk should be considered.

Magnetic sulfonated carbon. based solid acid catalysts (Fe/C-SO3H) were prepared by the pyrolysis of cellulose and subsequent sulfonation. The catalyst samples were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X. ray diffraction (XRD), X. ray photoelectron spectroscopy (XPS), Fourier transform infrared (FT-IR) spectroscopy, and vibrating sample magnetometry (VSM). Their catalytic properties for the hydrolysis of cellulose were investigated. Results show that Fe exists in the carbon body in the form of gamma-Fe2O3 and the Fe/C-SO3H catalyst has superparamagnetic properties. In the hydrolysis reaction, cellulose conversion reached 40.6% over Fe/C-SO3H under optimal conditions. Furthermore, the catalyst could be steadily dispersed in the reaction mixture and be separated using an externally applied magnetic field. However, the catalytic performance dropped after the first run. The reason for deactivation is deduced to be a reduction in the amount of sulfonic acid groups on the surface of the catalyst.

This paper discussed the coagulation characteristics of BPA with polyaluminum chloride (PACl-Al 13 ) as coagulant, examined the impact of coagulation pH, PACl-Al 13 dosage, TOC (total organic carbon) and turbidity on BPA removal, and analyzed the possible dominant mechanisms in water coagulation process. Formation and performance of flocs during coagulation processes were monitored using photometric dispersion analyzer (PDA). When the concentration of humic acid matters and turbidity was low in the solution, the experimental results showed that the removal of BPA experienced increase and subsequently decrease with the PACl-Al 13 dosage increasing. The optimal PACl-Al 13 dosage was found at BPA/PACl-Al 13 = 1:2.6(M/M) under our experiment conditions. Results show that the maximum BPA removal efficiency occurred at pH 9.0 due to the adsorption by Al 13 aggregates onto BPA rather than charge neutralization mechanism by polynuclear aluminous salts in the solution. The humic acid matters and kaolin in the solution have significant effect on BPA removal with PACl-Al 13 in the coagulation. The BPA removal will be weakened at high humic matters. The removal rate of BPA increased and subsequently decreased with the turbidity increasing.

The photodissociation dynamics of chloroiodomethane in the A-band has been investigated by ion velocity imaging coupled with a resonance enhanced multiphoton ionization (REMPI) scheme. Translational energies and angular distributions of the corresponding photofragments were obtained by detecting ion images of I*(5p P-2(1/2))and I (5p P-2(3/2)) at 266 and 277 nm. Single-peaked Gaussian translational energy distributions were found for I and I* and could be interpreted in terms of the soft radical approximation. The formation of I and I* took place via a fast direct dissociation process on a repulsive potential energy surface. The obtained anisotropy parameter 6 proved that the existence of a nonadiabatic transition between the (3)Q(0) and (1)Q(1) states, and excitation at these wavelengths was predominated to the (3)Q(0) state. The nonadiabatic transition between the (3)Q(0) and (1)Q(1) states is stronger at shorter wavelengths. Around 235 nm, the isotropic Cl and Cl* ion images Suggest that the observed chlorine atoms come from the secondary UV photodissociation of CH2Cl radicals which are initially produced by the photodissociation of CH2ICl.

The Photodissociation dynamics of C6H11Br was investigated near 234 nm. A two-dimensional photofragment ion-velocity imaging technique coupled with a (2+1) resonance-enhanced multiphoton (REMPI) ionization scheme was utilized to obtain the angular and translational energy distributions of the nascent Br(P-2(3/2)) and Br * (P-2(1/2)) atoms. The relative quantum yields were obtained from (2+1) resonance-enhanced multiphoton ionization (REMPI) of the photofragment Br*(P-2(1/2)) and Br(P-2(3/2)). It was suggested that Br* came from the direct dissociation of S-1 state mostly, while Br atom was produced by non-adiabatic transition between the S-2 and T-3 states. Consequently, the higher internal energy distribution and the broader translational energy distribution of Br channel than those of Br * formation channel can be explained well. The results indicated that a large fraction of the available energy translated into the internal energy of the fragments, which can be explained using the soft impulsive model. However, comparing with other long-chain bromoalkane, more available energy was translated into the kinetic energy. The relationship between the energy partition and the cyclohexyl radical structure were analyzed.

W-type barium ferrites Ba(MnZn) 0.3 Co 1.4 R 0.01 Fe 15.99 O 27 with R=Dy, Nd and Pr were prepared by chemical coprecipitation method. Effects of rare-earth elements (RE) substitution on microstructural and electromagnetic properties were analyzed. The results show that a small amount of RE 3+ ions can replace Fe 3+ ions and adjust hyperfine parameters. An obvious increase in natural resonance frequency and high frequency relaxation, and a sharp decrease for complex permittivity have been observed. Furthermore, the matching thickness and the reflection loss (RL) of one-layer ferrite absorber were calculated. It reveals that thin and broad-band can be obtained by RE-substitution. But only when the magnetic moment of RE 3+ is higher than that of Fe 3+ , can substitution be effective for higher RL. Dy-substituted ferrite composite has excellent microwave absorption properties. The frequency (with respect to −10 dB RL) begins from 9.9 GHz, and the bandwidth reaches far more than 8.16 GHz. The peak value is −51.92 dB at a matching thickness of 2.1 mm.

Er-doped silicon-rich SiO2 thin films were prepared by an rf co-sputtering method, followed by thermal annealing at 700–1200 degrees C for 30 min. The microstructure is studied by transmission electron microscopy (TEM) and x-ray diffraction (XRD). When the films are annealed at T>900 degrees C, silicon nanocrystals (nc-Si) enveloped by amorphous silicon (α-Si) can be observed. The thermal quenching behaviour at λ = 1.535 μm and its relation with the annealing temperature are also investigated. With the increasing annealing temperature, the portion of α-Si and the intensity quenching both decrease. Efficient luminescence from Er ions and weak intensity thermal quenching can be obtained from the sample annealed at 1100 degrees C. The role of α-Si in the non-radiative processes at T>100 K is discussed.

Rhododendron delavayi Franch. is an important ornamental plant and often plays a role in natural hybridization with other sympatric species in Rhododendron subgenus Hymenanthes. Fifteen microsatellite loci were developed and characterized in this species. The average allele number of these microsatellites was four per locus, ranging from three to six. The ranges of expected (HE) and observed (HO) heterozygosities were 0.0365 to 0.7091 and 0.0263 to 0.9512, respectively. Cross-species amplification in R. agastum and R. decorum showed that a subset of these markers holds promise for congeneric species study. These sets of markers are potentially useful to investigate the genetic structure and gene flow of R. delavayi and other congeneric species.

Liquid carbosilane was synthesized and analyzed by infrared (IR) and H-NMR (nuclear magnetic resonance) spectroscopy. Silicon carbide (SiC) powders were prepared by chemical vapor deposition (CVD) at 850°C and 900°C from liquid carbosilanes. The product powders were characterized by IR spectroscopy, X-ray diffractometry (XRD) and scanning electron microscopy (SEM). Results show that liquid carbosilane synthesized was the mixture of several oligomers that had a Si-C backbone. The powders prepared at 850°C contain some organic segments, and those prepared at 900°C are pure nanosized SiC powders, which are partly crystallized, the size of which is about 50–70 nm.

To identify epitope relating to BAC5 mcAb, a kind of monoclonal antibody (mcAb) located on the surface of nasopharyngeal carcinoma (NPC) cells. Using BAC5 mcAb as a selected target, the 3 rounds of biopanning to a 12 mer random peptide library (RPL) presented by M13 phages were carried out. The positive M13 phage clones were chosen and confirmed with sandwich ELISA for antibody capture and competitive assay. The exogenous DNA fragments in the positive/negative M13 phages were sequenced to deduce and compare the order of the amino acids of exogenous peptides among the phage clones. 77% (35/45) of the phages eluted from the 3rd round of biopnning could be captured by BAC5 mcAb. The 3 kinds of the peptides were displayed by M13 phages from the 8 positive clones identified with competitive assay. The same character of “-P-V-” structure existed near N-terminus of the 3 different peptides, i. e.-H-Q-S-H-Y-P-Y-P-V-V-S-L- (4/8)-Q-N-Q-A-W-F-S-Q-P-V-R-M-(3/8) and T-Q-A-Y-K-G-F-P-V-L-P-S- (1/8) in comparison with the peptide “-N-H-Q-S-T-F-W-Q-K-W-T-A-” displayed by M13 phages from the negative clones (6/6). BAC5 mcAb can recognize the 3 kinds of the peptides with-P-V-structure near N-terminus. These peptides mimic the structure of the epitope on the surface of NPC cells recognized by BAC5 mcAb.

High carbon martensitic steel specimens with various volume fractions of secondary carbide, ranging from 1.3% to 9.8% were obtained by changing the carbon content and air-quenching from the same reaustenitizing temperature. The carbon contents in the martensitic matrix of the steels were determined using a computerized X-ray diffractometer and were almost constant. The effect of volume fraction of secondary carbide on the three-body abrasion wear resistance of martensitic steel was investigated in a low-speed grinding system using silica and glass sand abrasives which had different sizes. It is shown that separate secondary carbide, which could increase the hardness of the steel, not only did not increase the steel's microcutting wear resistance because of the “size effect” but also decreased the wear resistance because of easy spalling. However, the micropitting wear resistance of martensitic steel could be improved by the separate secondary carbide. The role of secondary carbide during three-body abrasion depended on the hardness and size of abrasives used, which could significantly change the wear mechanism.

The electronic structures and optoelectronic properties of C/Ge-doped single-walled armchair silicon nanotubes were determined by using first-principles calculations in the framework of density-functional theory. In particular, the calculated results indicate that both pure and C/Ge-doped silicon nanotubes display a direct band gap. The band gap is decreased firstly and then increased for the silicon nanotubes doped with C and Ge, respectively. Moreover, the upper of valence band is mainly contributed by the Si-3p states and the lower of conduction band is primarily occupied by the Si-3p states. The state dielectric constant is improved and the optical absorption shows a red-shifted for the C-doped silicon nanotubes, whereas the state dielectric constant is reduced and the optical absorption shows a blue-shifted for the Ge-doped silicon nanotubes. The results provide an useful theoretical guidance for the applications of single-walled armchair silicon nanotubes in optical detectors.

It is an important approach to preventing nuclear proliferation that comprehensive nuclear test ban treaty is reached. How to judge whether a nuclear test has happened is a key point. In this paper we investigate a method to distinguish between a nuclear test and leakage from civilian nuclear reactor by measuring inert gas xenon nuclides 133mXe, 133Xe, 135Xe, and 131mXe. The distinction between the nuclear test and the reactor leakage is found by analyzing the variation of nuclide quantity with time in a complex decay chain. Two suspicious events in North Korea are measured and analyzed. In order to verify the theoretical results, an experiment of imitating plutonium irradiated by thermal neutron is designed.

According to the full-potential linearized augmented plane wave method, we calculate the optical properties of In-doped superlattices ZnO. The results reveal that the Fermi energy level enters into the conduction band after doping In. Dielectric function, absorption, refractive index, reflectivity are found to each have a new transition peak near the Fermi energy level. With the increase of the concentration, this transition peak shifts toward the low energy and the spectrum of the peak is the biggest for the two-layer doping case. The optical absorption edge decreases with the increase of doping concentration. Compared with In-doped ZnO supercell, ZnO superlattice has a high transmissivity in the visible light range.

In this paper we use first-principles full potential linearized augmented plane wave method (FP-LAPW) to inwestigate density of states (DOS), band structure and optical properties of the materials that doped with In and N. The results show that the doping structure has fine locat levels in both the spin-down direction and the spin-up direction and both state densities are symmetrical. The local levels are produced in the spin-down direction in the band gap, and co-doped compounds show being semi-metallic. The energy band structure indicates that the two co-doped compounds are still direct band gap semiconductors. The top of valence band shifts toward the low energy with the increase of the concentration of N, so obviously the band gap is widened. The main dielectric peak of imaginary part of dielectric function exists only at 8.58 eV, the position of main peak shifts to ward the right and the peak intensity increases significantly. The static dielectric constants of two different concentrations of N-doped structure also significantly increase, and a strong interaction takes place between the states of N 2p and In 5s. The number of peaks of co-doped absorption spectra reduces and the range of absorption wavelength is broadened.

The electronic density of states, spin-splittings and atomic magnetic moment of RE-TM compound SmCo55 have been studied by spin-polarized MS-Xα method. The results show that a few of electrons are transferred to Sm(5d00) o rbital because of orbital hybridization between Sm and Co atoms in the compound. The exchange interactions between 3d and 5d electrons lead to the magnetic coupling betwee n Sm and Co, and therefore, result in the long-range ferromagnetic order inside the compound SmCo55 There are some negative exchange couplings occ urring at six levels, which make the Curie temperature of SmCo55 decrease disti nctly, com pared with pure Co. The spin moment and orbital moment of 2c and 3g site s have been also studied in this paper. We found that the spin moment, orbital m oment and its quenched part of Co(2c) are greater than that of Co(3g).Th erefore, the strength of L-S coupling of the former is a little greater tha n that of the latter, which implies the contribution to magneto-anisotropy of 2c site is greater than that of 3g site. But the unquenched orbital mome nt in 2c site is slightly smaller than that in 3g site. So, the differen ce of contribution to the anisotropy between the two Co-sites is not very disti nct. Considering the localization of 4f electrons and the few 5d electrons, the magnetic moment of Sm atom will be 129μBB in SmCo55, wh ich is in agreem ent with the experiments of Sm3+3+ ion-moment (132—163μBB) and the Sm atom-moment (174μBB) in metal.

The band of charge transfer transition was detected in optical absorbtion spectra when molecule adsorbed on the silver surface in silver sol. The process of charge transfer between molecule and surface was mainly studied and some explanations were given.

This paper is based on the pictureo of classical nucleation theory. However, it is reformulated in a quantum mechanical dynamical description. Thereby, the nonequilibrium statistical operator method is used to study the dissipation of liquid-phase embryo growth. On the assumption that the molecule exchanges between the liquid phase and gas phase are small, we verify the important result that the homogenous nucleation process is irreversible. Also, we derive the principle of minimum production of entropy for stationary states in nucleation. The present discussion completes the irreversible thermodynamics of nucleation.