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With an upsurge of biodegradable metal implants, the research and application of Mg alloys in the gastrointestinal environment of the digestive tract have been of great interest. Digestive enzymes, mainly pepsin in the stomach and pancreatin in the small intestine, are widespread in the gastrointestinal tract, but their effect on the degradation of Mg alloys has not been well understood. In this study, we investigated the impacts of pepsin and pancreatin on the degradation of Mg-2Zn alloy wires. The results showed that the pepsin and pancreatin had completely different even the opposite effects on the degradation of Mg, although they both affected the degradation product layer. The degradation rate of Mg wire declined with the addition of pepsin in simulated gastric fluid (SGF) but rose with the addition of pancreatin in simulated intestinal fluid (SIF). The opposite trends in degradation rate also resulted in completely different degradation morphologies in wires surface, where the pitting corrosion in SGF was inhibited because of the physical barrier effect of pepsin adsorption. In contrast, the adsorption of pancreatin affected the integrity of magnesium hydrogen phosphate film, causing a relatively uneven degraded surface. These results may help us to understand the role of different digestive enzymes in the degradation of magnesium and facilitate the development and clinical application of magnesium alloy implanted devices for the digestive tract., Graphical abstract Image 1, Highlights • The pepsin in SGF and pancreatin in SIF have opposite effects on the degradation rate of Mg. • Both enzymes can adsorb on the surface of Mg wire and affect the formation of the degradation layer. • The physical barrier effect of pepsin adsorption retarded the pitting corrosion and corrosion rate in SGF. • Adsorbed pancreatin affected the integrity of the products layer in SIF, resulting in an accelerated corrosion rate.

During the underground coal gasification process, due to the particularity of the gasification channel, a large amount of coal pyrolysis will occur in the coal seam. By studying the characteristics...

Phenyl molybdate-modified phenolic fibers (PMoPFs) were prepared by melt spinning from the corresponding resin which was polymerized from phenol, formaldehyde, and phenyl molybdate, followed by solution curing and then heat curing processes. The molecular structures, including characteristic groups and molecular weight, were examined by nuclear magnetic resonance, Fourier transform infrared spectroscopy, and gel permeation chromatography. The influences of the curing processes were demonstrated by mechanical properties, scanning electron microscopy, and thermogravimetric analysis characterization. PMoPF with 8 wt% molybdic acid and cured in an oven possessed a tensile strength as high as 187 MPa, initial decomposition temperature of 300°C, and a char yield under nitrogen atmosphere at 800°C as high as 66.0%, with the molybdate (MoO4 2−) groups being introduced into the phenolic main chain.

TiAl alloy was successfully brazed with Ag-CuO filler in air atmosphere under simple technical conditions. The wettability of a series of Ag-CuO fillers on TiAl was analyzed. Ag-2mol%CuO filler possessed good wetting behavior on TiAl alloy. The microstructure and mechanical properties of the brazed joints were investigated. Oxide layers can be found on both sides, which can be divided into external TiO2-rich layer and internal Al2O3-rich layer. The maximum shear strength of the joint was obtained at 1020 °C holding for 20 min.

Conventional Ag-CuO braze can lead to two electrolyte/interconnect joining issues: over-oxidation at the steel interconnect and hydrogen-induced decomposition of CuO. This work demonstrates that a pure Ag interlayer, instead of Ag-CuO braze, can join YSZ electrolyte to AISI 441 interconnect in air. Reliable joining between YSZ and AISI 441 can be realized at 920 °C. A dense and thin oxide layer (~2 μm) is formed at the AISI 441 interface. Also, an interatomic joining at the YSZ/Ag interface is detected by TEM observation. Obtained joints display high shear strengths (~86.1 MPa), 161% higher than that of joints brazed by Ag-CuO braze (~33 MPa). After aging in reducing and oxidizing atmospheres (800 °C/300 h), joints remain tight and dense, indicating a better aging performance. This technique eliminates the CuO-induced issues, which will extend lifetimes for SOFC/SOEC stacks and other ceramic/metal joining applications.

A highly sensitive fluorescent “turn-on” probe NapP-deap based on naphthalimide derivative was developed that bound Hg2+ ions rapidly in the N-2-hydroxyethylpiperazine-N-ethane-sulphonic acid(HEPES) buffer solution via photo-induced electron transfer(PET) being inhibited mechanism. The titration experiment displayed that the emission intensity of NapP-deap at 540 nm was almost linearly increased by about 3-fold. The Job’s plot showed a stoichiometry factor of 1:1 of the ligand-to-metal ratio. The detection limit of fluorescent probe was calculated to be 6.2×10−9 mol/L. 1H NMR studies could confirm that one Hg2+ ion was bound by the N atoms(a, b) of piperazine or the N atom(c) of pyridine. The fluorescent probe could be used for the detection of Hg2+ ions in living cells.

There has been a stable carbonate reservoir developed in the Middle Permian of DXC structure which is in southwest Sichuan. At present, The four producing gas wells are located at middle, north or south of the structure respectively. With analysis on reservoir characteristics and production testing characteristics of gas wells, research on percolation condition of gas reservoir using dynamic monitoring data, and reservoir types have been determined, gas well productivity has been evaluated, high yield model has been cleared. The conclusions from this research: ① The compacted limestone reservoir in the Middle Permian of DXC structure had constructed good storage-permeation body by perfect configuration of pore, hole and fracture. ② The production testing effect is very well in this reservoir, and The stable production potential of each well is great too. ③ There was a positive correlation between the gas well productivity and fault size (extended length and fault throw), the wells spaced model - “fault model” could be extended in the similar gas reservoirs. ④ The DXC area had gotten 41.42 billion cubic meters new-proved gas reserve, there are favorable zones including “one area and one band” in the Middle Permian of southwest Sichuan which has good exploration and development potential.

Peroxynitrite is a damaging agent of oxidative stress that has been difficult to monitor in living cells. Here, an isatin-based chemiluminescent probe for peroxynitrite is reported., Peroxynitrite (ONOO–) is a highly reactive oxygen species which has been recognized as an endogenous mediator of physiological activities like the immune response as well as a damaging agent of oxidative stress under pathological conditions. While its biological importance is becoming clearer, many of the details of its production and mechanism of action remain elusive due to the lack of available selective and sensitive detection methods. Herein, we report the development, characterization, and biological applications of a reaction-based chemiluminescent probe for ONOO– detection, termed as PNCL. PNCL reacts with ONOO–via an isatin moiety through an oxidative decarbonylation reaction to initiate light emission that can be observed instantly with high selectivity against other reactive sulphur, oxygen, and nitrogen species. Detailed studies were performed to study the reaction between isatin and ONOO–, which confirm selectivity for ONOO– over NO2˙. PNCL has been applied for ONOO– detection in aqueous solution and live cells. Moreover, PNCL can be employed to detect cellular ONOO– generated in macrophages stimulated to mount an immune response with lipopolysaccharide (LPS). The sensitivity granted by chemiluminescent detection together with the specificity of the oxidative decarbonylation reaction provides a useful tool to explore ONOO– chemistry and biology.

Sea cucumber saponins (SCSs) exhibit a wide spectrum of bioactivities, but their metabolic characteristics are not well elucidated. In this study, the metabolism of holothurin A (HA) and echinoside A (EA), 2 major saponins in sea cucumber, by gut microflora were investigated. First, we conducted an in vitro study, where in the SCSs were incubated with intestinal microflora and the metabolites were detected by high pressure liquid chromatography-high resolution mass spectrometry. We also conducted an in vivo study on rats, where in the intestinal contents, serum, urine, and feces were collected and evaluated after oral administration of SCSs. In the in vitro study, we identified 6 deglycosylated metabolites of HA and EA, assigned M1-M6. In the in vivo study, we found all the deglycosylated metabolites in the intestinal contents after oral administration, and both the metabolites and their prototype components could be absorbed. Four metabolites were identified in the serum, 6 in the urine, and 4 in the feces. The saponins with different structures showed different absorption characteristics in rats. According to our results, deglycosylation is the main intestinal microflora-mediated metabolic pathway for SCSs, and both the SCSs and deglycosylated metabolites can be absorbed by intestine. This study improves the understanding of the metabolism of HA and EA by gut flora, which will be useful for further analysis of the bioactivity mechanism of SCSs.

A series of monophenyl borate (MPB) modified high-ortho phenolic copolymer fibers (BOPFs) were prepared by melt-spinning of the high-ortho phenol-formaldehyde resins with different content of MPB, and cured in a formaldehyde solution. The solution curing fibers were heated up to 240 °C at elevated temperatures in N2. The effect of MPB on the structure and properties of the BOPFs was investigated by Fourier transform infrared spectrometer (FTIR), nuclear magnetic resonance spectroscopy (NMR), thermogravimetric analysis (TGA) and scanning electron microscope (SEM). The results show that a B-O linkage inserts into the high-ortho phenolic copolymer molecular chain with the addition of MPB, and increases the crosslinkage and thermal stability. The peak of O/P (ortho/para) value of fiber (1.94) and elongation (5.6 %) were obtained when BOPFs-4 was heat-cured at 240 °C for 2 h.

We report a rational design and mechanism studies of mitochondria-immobilized iridium(iii) complexes that can kill cancer cells by targeting mitochondrial metabolism., Cancer cell metabolism is reprogrammed to sustain the high metabolic demands of cell proliferation. Recently, emerging studies have shown that mitochondrial metabolism is a potential target for cancer therapy. Herein, four mitochondria-targeted phosphorescent cyclometalated iridium(iii) complexes have been designed and synthesized. Complexes 2 and 4, containing reactive chloromethyl groups for mitochondrial fixation, show much higher cytotoxicity than complexes 1 and 3 without mitochondria-immobilization properties against the cancer cells screened. Further studies show that complexes 2 and 4 induce caspase-dependent apoptosis through mitochondrial damage, cellular ATP depletion, mitochondrial respiration inhibition and reactive oxygen species (ROS) elevation. The phosphorescence of complexes 2 and 4 can be utilized to monitor the perinuclear clustering of mitochondria in real time, which provides a reliable and convenient method for in situ monitoring of the therapeutic effect and gives hints for the investigation of anticancer mechanisms. Genome-wide transcriptional analysis shows that complex 2 exerts its anticancer activity through metabolism repression and multiple cell death signalling pathways. Our work provides a strategy for the construction of highly effective anticancer agents targeting mitochondrial metabolism through rational modification of phosphorescent iridium complexes.

This work reported a highly sensitive ethanol sensor assembled from raspberry-like hierarchical Ce-doped WO3 nanoparticles. The Ce-doped WO3 nanoparticles doped with different contents (0, 2, 4 and 8 at%) of Ce were synthesized by a facile hydrothermal method. The crystalline structure and the micromorphology of Ce-doped WO3 nanoparticles were measured by x-ray diffraction (XRD) and field-emission scanning electron microscopy (FESEM), respectively. The x-ray photoelectric spectroscopy (XPS) and transmission electron microscopy (TEM) attached with energy-dispersive spectroscopy (EDS) confirmed the elemental distribution and the chemical state of surface elements. Comparison between the pristine and Ce-doped WO3 samples revealed that the doping of Ce on WO3 can powerfully improve the response ability to ethanol. As the doping content of Ce element was 4 at%, the sensor exhibited optimal response to ethanol in the range of 0.1–50 ppm at the working temperature of 350 °C. The response can achieve a high value of 12.3 for detecting 1 ppm ethanol with a fast response/recovery (6s/6s). Impressively, the sensor still maintained a good response (8.1) to ethanol even at sub-ppm level (0.1 ppm ethanol). This work will pave a platform for design and development of highly sensitive ethanol sensors.

C14H12Br2O2, monoclinic, C2/c (no. 15), a = 27.323(3) Å, b = 5.8516(6) Å, c = 8.9145(10) Å, β = 103.596(3)°, V = 1385.4(3) Å3, Z = 4, R gt(F) = 0.0378, wR ref(F 2) = 0.1019, T = 296(2) K.

It is interesting in low-dimensional nanostructures of silicon that the two quantum effects play different roles in nanosilicon emission, in which the quantum confinement (QC) effect opens band gap and makes emission shift into shorter wavelengths (blue-shift) as the size of the nanocrystals is reduced; however the breaking symmetry originating from impurities on nanosilicon produces the localized electronic states in band gap and makes emission shift into longer wavelengths (red-shift). The results of experiment and calculation demonstrated that the energy levels of nanosilicon can be manipulated through these quantum effects, where the curved surface (CS) effect of impurity atoms bonding on nanosilicon is important in breaking symmetry of nanosilicon system. Here, the CS effect plays an important role on impuritied nanosilicon in smaller scale with larger surface curvature, in which a few characteristic parameters have been found to describe the breaking symmetry of nanosilicon system, such as bonding angle and projecting length of bonds on curved surface. More interesting, the coupling ways between the QC effect and the CS effect determinate the levels position of localized states in band gap and manipulate emission wavelength, where a few new phenomena were explored.

Plasmonic lattice structure induced by pulsed laser was observed in the Talbot reflection effect image, which could be used to fabricate nanostructures on silicon. It is interesting that annealing and quenching effects obviously affect the localized states emission on nanosilicon prepared by pulsed laser, in which the annealing parameters are important, such as temperature and time. It is found that the laser annealing is a good way to replace the traditional annealing way in furnace, especially for rapidly annealing. A physical model is made to explain the annealing and quenching effects in the localized states emission on nanosilicon.

High-ortho boron-containing phenolic fibers were prepared, and cured in a solution of formaldehyde and hydrochloric acids. The resulted fibers were heattreated in N2 at tiered temperature. Differential scanning calorimetry and thermogravimetric analysis were employed to characterize thermal performance. The results show that the addition of boron in the precursor resin can increase the peak of curing temperature and thermal stability.

Sex hormones, especially 17β-estradiol (E2) and testosterone (TEST), play crucial roles in the oncogenesis and progression of liver cancer via hormone-related receptors. As women have a lower rate of hepatocellular carcinoma (HCC) than men, estrogens might attenuate the occurrence and development of HCC. This study aimed to investigate the inhibitory effects and mechanisms of E2 on TEST-induced HCC development; the HepG2 cell line was used as an in vitro model. Five endpoints, including cell viability, cell apoptosis, cell cycle, receptor protein expression, and messenger RNA transcription, were investigated. Different roles and the ratios of androgen receptor (AR) and 3 estrogen receptor (ER) subtypes were also estimated. Cell viability assay showed that co-treatment of E2 and TEST resulted in a significant inhibition of E2-induced or TEST-induced cell proliferation. Flow cytometry analysis revealed that combined treatment of E2 and TEST blocked the cell cycle in the G0/G1 phase as well as induced cell early apoptosis, characterized by decreased cyclin-dependent kinase transcription and the ratio of Bcl-2/Bax. Real-time quantitative polymerase chain reaction and Western blot analysis results further demonstrated that estrogen receptor estrogen receptor α66 (ERα66) and estrogen receptor β (ERβ) were upregulated, whereas AR and estrogen receptor α36 (ERα36) were downregulated, irrespective of whether E2 and TEST were considered separately or together, whereas the combined treatment of E2 and TEST resulted in a decrease in the ERα66/ERβ ratio, the ERα66/ERα36 ratio, and the ERβ/ERα36 ratio, but with an increase in the ERα66/AR ratio, the ERα36/AR ratio, and the ERβ/AR ratio. To sum up, E2 could inhibit TEST-induced cell proliferation by modulating the ratio of different hormone-related receptors.

Cadmium uptake in rice is believed to be mediated by the Fe transport system. Phyto-available Cd can be changed by Fe fertilization of substrates. This work investigated whether and how Fe fertilization affects mitigation of Cd accumulation in paddy rice. A 90-d soil column experiment was conducted to study the change of Cd and Fe availability in soil after Fe fertilization (ionic and chelated Fe). A low-Cd accumulating cultivar (TY116) and a high-Cd accumulating cultivar (JY841) were grown in two Cd-polluted paddy soils amended with chelated Fe fertilizers. Additionally, both cultivars were grown in hydroponics to compare Fe-related gene expression in EDDHAFe-deficient and EDDHAFe-sufficient roots. The column experiment showed that EDTANa2Fe(II) and EDDHAFe(III) fertilization had a better mitigation effect on soil Cd availability compared to FeSO4·7H2O. Moreover, the field experiment demonstrated that these two chelated fertilizations could reduce Cd concentrations in brown rice by up to 80%. Iron concentrations in the brown rice were elevated by Fe chelates. Compared to EDDHAFe(III), EDTANa2Fe(II) fertilization had a stronger mitigation effect by generating more EDTANa2Cd(II) in the soil solution to decrease phyto-available Cd in the soil. While EDDHAFe(III) fertilization could increase soil pH and decrease soil Eh which contributed to decreasing phyto-available Cd in a contaminated soil. In the hydroponic experiment, Fe sufficiency significantly reduced Cd concentrations in above-ground organs. In some cases, the expression of OsIRT1, OsNRAMP1 and OsNRAMP5 was inhibited under Fe sufficiency relative to Fe deficiency conditions. These results suggest that mitigation of rice Cd by Fe chelate fertilization results from a decrease in available Cd in substrates and the inhibition of the expression of several Fe-related genes in the IRT and NRAMP families.

ZnS:Cu 2+ nanoparticles were synthesized by the solvothermal method. The results showed that the nanoparticles with the diameters of 10–20 nm were of cubic zinc blende structure. The Cu 2+ ions were substitutionally incorporated into the ZnS lattice and the maximum concentration of the Cu 2+ ions in the ZnS nanoparticles can reach to 2.84%. The ferromagnetism property of the ZnS:Cu 2+ nanoparticles was observed around room temperature, which was explained by the super-exchange mechanism.

Vapor pressures, vaporization enthalpies and acentric factors for new compounds, diethoxy(methyl)(o-tolyl)silane, diethoxy(methyl)(m-tolyl)silane and diethoxy(methyl)(p-tolyl)silane were reported. The saturated temperature was measured using the inclined ebulliometer in the pressure range from 2000 to 61,000 Pa and the normal boiling point was measured according to the Siwoloboff method. The standard vaporization enthalpy was derived from the temperature dependence of vapor pressure data. The critical parameters were estimated by an improved group contribution method and the acentric factors have been estimated from the Antoine equation and the experimental normal boiling points.

Timing of petroleum accumulations and distribution of vertical basin-scale sealing beds are important in the study of superimposed basins. This information can be used to divide petroleum accumulations of different times into different petroleum-forming assemblages vertically so as to reconstruct the petroleum accumulation process and distribution more accurately. The Mahu-West Well Pen 1 combination petroleum system in the Junggar Basin is taken as the case study. By isotopic K-Ar dating of authigenic illite, optical feature of organic inclusions, and fluid inclusion homogenization temperature, combined with burial and thermal history analysis, timing of petroleum accumulations is defined, i.e., P2–3, T3, J2—K1 and N. According to the vertical sealing mudstones of T3b, J1s1, and K1tg, four petroleum-forming assemblages were divided including C—T3, T3—J1, J2—K1, and K-N. 摘 要: 叠合盆地油气成藏研究不仅需要确定成藏期次，而且还要结合垂向封隔层的分布，将不同成藏期的油气藏从垂向上划分为不同的成藏组合，以期更准确地反映油气成藏过程和描述油气空间分布。以准噶尔盆地玛湖—盆1井西复合含油气系统为例，基于储集层自生伊利石K-Ar同位素测年、包裹体光性特征与均一温度分析、埋藏-热演化史分析，确定该油气系统共有4个主要的成藏期(P2—3、T3、J2—K1和N)。在此基础上，结合垂向封隔层(T3b、J1s1、K1tg泥岩)的分布，划分出C—T3、T3—J1、J2—K1和K—N等4个成藏组合，不同的成藏组合在不同区带具有不同的勘探意义。 Key words: petroleum accumulation timing, reservoir-forming assemblage, petroleum migration, Junggar Basin, superimposed basin

To investigate the chief reason for phosphorus uptake by microorganisms affected by substrates in sequencing batch reactors with the single-stage oxic process, two typical substrates, glucose (R1) and acetate (R2) were used as the sole carbon source, and the performances of phosphorus removal and the changes of intracellular storage were compared. The experimental results showed that the phenomenon of excess phosphorus uptake was observed in two reactors, but bacteria’s capability to take in phosphorus and its intracellular storage were obviously different under the same operational condition. After steady-state operation, total phosphorus (TP) removed per MLVSS in R1 and R2 was 6.7–7.4 and 2.7–3.2 mg/g, respectively. The energy storage of poly-β-hydroxyalkanoates (PHA) was nearly constant in R1 during the whole period, and another aerobic storage of glycogen was accumulated (the max accumulation of glycogen was 3.21 mmol-C/g) when external substrate was consumed, and then was decreased to the initial level. However in R2, PHA and glycogen were both accumulated (2.1 and 0.55 mmol-C/g, respectively) when external substrate was consumed, but they showed different changes after the period of external consumption. Compared to rapid decrease of PHA to the initial level, glycogen continued accumulating to the peak (0.88 mmol-C/g) in 2 h of aeration before decreasing. During the aeration, the accumulations/transformations of internal carbon sources in R1 were higher than those in R2. In addition, obvious TP releases were both observed in R1 and R2 other than PHA and glycogen during the long-term idle period; moreover, the release content of phosphorus in R1 was also higher than that in R2. The researches indicated that different aerobic metabolism of substrate occurred in R1 and R2 due to the different carbon sources in influent, resulting in different types and contents of aerobic storage accumulated/translated in bacteria of R1 and R2. As a result, ATP content provided for phosphorus uptake was different in R1 and R2, and the capability to take up phosphorus was also different from each other.

Stimulated emission has been observed from oxide structure of silicon when optically excited by 514 nm laser. The twin peaks in the region from 690 nm to 700 nm are dominated by stimulated emission which can be demonstrated by its threshold behavior and transition in linear evolution. The oxide structure was fabricated by laser irradiation and annealing treatment on silicon. A model for explaining the stimulated emission has been proposed in which the trap states of the interface between oxide of silicon and porous nanocrystal play an important role.

Stimulated emission has been observed from oxide structure of silicon when optically excited by 514 nm laser. The photoluminescence (PL) pulse has a Lorentzian shape with a full width at half maximum (FWHM) of 0.5–0.6 nm. The twin peaks at 694 nm and 692 nm are dominated by stimulated emission which can be demonstrated by its threshold behavior and transition from sub-threshold to linear evolution in light emission. The gain coefficient from the evolution of the peak-emission intensity as a function of the optically pumped sample length has been measured. The oxide structure was fabricated by laser irradiation and annealing treatment on silicon. A model for explaining the stimulated emission has been proposed in which the trap states of the interface between oxide of silicon and porous nanocrystal play an important role.

Stimulated photoluminescence (PL) emission has been observed from an oxide structure of silicon when optically excited by a radiation of 514nm laser. Sharp twin peaks at 694 and 692nm are dominated by stimulated emission, which can be demonstrated by its threshold behaviour and linear transition of emission intensity as a function of pump power. The oxide structure is formed by laser irradiation on silicon and its annealing treatment. A model for explaining the stimulated emission is proposed, in which the trap states of the interface between an oxide of silicon and porous nanocrystal play an important role.

Electronic probe microanalysis (EPMA) results of reservoir calcite cement from fourteen core samples in the Junggar Basin show that Mn-content varies largely between different samples from below the detect limitation to 4.14%, while it displays a generally good correlation with oil-gas shows. This, therefore, likely indicates that concentration of the Mn-content of the calcite cement has a close relation to the intensity of petroleum fluid charging during hydrocarbon secondary migration. In order to assess this hypothesis, oxygen and strontium isotopic measurements on sixteen calcite veins host in source sequences were carried out to investigate the feature of the oil-source petroleum fluid. Analytical results imply that during hydrocarbon generation and migration, deep hot fluid has dissolved volcanic minerals interlined between mudstone source rocks. As Mn is a kind of typical trace element enriched in volcanic rocks, it is reasonable to conclude that the petroleum fluid formed in the source sequences would be Mn-rich. Consequently, calcite cements precipitated from such Mn-rich petroleum fluid would be Mn-rich accordingly. Due to the geologic chromatographic effect during migration along reservoir rocks, the decreasing of the Mn-content of the reservoir calcite cements indicates the migration direction. Then, this novel geotracer was further successfully applied in the study of hydrocarbon migration in the Junggar Basin in combination with organic geochemical analyses during the hydrocarbon migration. The Mn content of the reservoir calcite cement appears promising as a novel inorganic geotracer for the petroleum migration. This paper represents a search for novel indicators of secondary petroleum migration in tectonically complex basins based on fundamentals of the reservoir fluid-rock interactions.

In our experiment, it was observed that silicon nanocrystal rapidly grows with irradiation of electron beam on amorphous silicon film prepared by pulsed laser deposition and shape of silicon nanocrystal is usually sphere in smaller nanoscale with less exposure time under electron beam, in which the quantum dots are prepared in nanoscale near 3 nm. In the electron interaction process, it was investigated that the various crystals structures in different orientations occur in the same time and the condensed structures of silicon nanocrystal are changed with different impurity atoms in silicon film.

It is very interesting that magic electron affection promotes growth of nanocrystals due to nanoscale characteristics of electronic de Broglie wave which produces resonance to transfer energy to atoms. In our experiment, it was observed that silicon nanocrystals rapidly grow with irradiation of electron beam on amorphous silicon film prepared by pulsed laser deposition (PLD) and silicon nanocrystals almost occur in sphere shape on smaller nanocrystals with less irradiation time of electron beam. In the process, it was investigated that condensed structures of silicon nanocrystals are changed with different impurity atoms in silicon film, in which localized states emission was observed. Through electron beam irradiation for 15min on amorphous Si film doped with oxygen impurity atoms by PLD process, enhanced photoluminescence emission peaks are observed in visible light. And electroluminescence emission is manipulated into the optical communication window on the bigger Si-Yb-Er nanocrystals after irradiation of electron beam for 30min.

Ni (Nickel) piping, Contact openness, and W (Tungsten) recess are three major defects encountered in 40nm Contact related process development. In this paper, PAI (Pre- Amorphous Implantation) and Ni capping layer were optimized for Ni piping reduction. Contact etch process window was enlarged to eliminate Contact openness. The specific PMOS-localized defect phenomenon was studied. High ILD (Interlayer Dielectric) CMP oxide loss was found responsible to cause poor post-CMP uniformity, which was the main contributor to W recess defect thereafter. Finally, we had obtained an effective ILD thickness and uniformity control in CMP and thus, solving W recess defect.

Five novel cardiac glycosides with two types of unusual aglycone [funingenin A (2a) and B], named funingenosides E-I (2-6), together with a known compound, funingenoside B (1), were isolated from the aerial part of Parepigynum funingense Tsiang et P. T. Li (Apocynaceae). The structures of 2-6 were elucidated by means of MS, IR, NMR spectral analyses and chemical degradation. The possible biogenetic pathway of the two types of cardiac glycosides was also discussed.

MCl2 (M = Ni, Co, Sn, or Mn) and PPh3 together acted as a catalyst for the radical polymerization of methyl methacrylate (MMA) in the presence of ethyl 2-bromoisobutyrate as an initiator. The four systems all led to conventional radical polymerizations, which yielded polymers with a weight-average molecular weight/number-average molecular weight (Mw/Mn) ratio greater than 2.0 and became well controlled when a certain amount of FeCl3·6H2O was added. The polymerizations of MMA catalyzed by these four FeCl3-modified catalyst systems provided well-defined polymers with low polydispersities (Mw/Mn < 1.28). © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 2625–2631, 2005

The high-ortho epoxy phenolic fibers (HEPFs) were prepared by the crosslinking of as-spun filaments derived from melt-spinning of the epoxy novolac resins copolymerized among epichlorohydrin (ECH), phenol and formaldehyde, and cured in a combined solution of formaldehyde and hydrochloric acid with a different heating rate. The changes in functional groups, thermal performance and mechanical properties during the different heating rates in solution curing were characterized. The results show that a peak of thermal stability and mechanical properties can be obtained with increasing heating rate, and crosslinking structure and characteristic group have changed after the solution curing. The epoxy phenolic fibers show great potential in the application of elastic flame-resistant textiles, aero-composites and precursors for activated carbon fibers used in electronic devices.

Study on the carbonate content and oxygen isotope of a sediment section in Dabusu Lake revealed that this region has experienced several cold-wet and warm-dry climatic cycles since 15400 a BP. It was about 6740 a BP when the climate in the region reached a relatively stable warm stage, so that the lake water was gradually condensed and finally a lake was formed.

In this paper, the principle and method of the electron temperature measurement by means of electron cyclotron emission (ECE) have been discribed. Several results under different conditions on HL-1M tokamak have been given. The hollow profile of electron temperature appears in some stages, such as current rising, pellet injection and impurity concentration in the plasma centre. When the bias voltage is applied, the electron temperature profile become steeper. All of the phenomena are related with the transport in plasma centre.

A fungi strain named Fusarium sp. was isolated from manganese-electrolysed slag by using a gradient dilution spread plate method, identified by 26S RNA sequence analysis and phylogenetic tree analysis, and explored for the bioleaching capacity to manganese (II) from manganese-electrolysed slag in liquid mineral medium under different environmental conditions, including system temperature, incubator rotation speed and initial pH value. DNA sequence and phylogenetic analysis indicated the name of this fungi strain, that is, Fusarium sp., and higher bioleaching efficiencies (71.6%) of manganese by this fungi were observed when the bioleaching was carried out under the optimized conditions as follows: contact time: 72 h; system temperature: 28 degrees C; inoculums concentration: 2% (v/v); incubator rotation speed: 150 rpm; pH 4.0. Because of its low cost, environment friendliness and better efficiency, the bioleaching technique will have a significant impact on manganese-electrolysed slag pollution mitigation.

Using a floating double probe, we have determined values for the cross-field diffusion coefficient D⊥(a) (0.2–1.0 m2/s), the gross particle confinement time τp (10–100 ms) and the radial particle flux Γ(a) (1019–1020 m−2 s−1), near the limiter radius for Ip = 100 kA, ne = (1.0–4.5) × 1019/m3 and BT = 1.4–2.5 T. The parametric dependence of the edge plasma parameters on BT and line averaged density, n¯e, has been found to be non-linear. The turbulence characteristics have been studied using spectroscopy, microwave reflectometry, magnetic coils and an array of Langmuir probes. The experimental results indicate that turbulent diffusion plays a key role in the particle transport.

4 He + -H elastic recoil detection is used to profile hydrogen distributions in semi-insulating polysilicon films (SIPOS). The relation between hydrogen content and reactant gas flow ratio r , and the hydrogen release from SIPOS after annealing were measured. The experimental results show that the hydrogen content is much less than the oxygen content in SIPOS films and rapidly decreases after annealing. The relation between hydrogen content and oxygen content, and the hydrogen incorporation with oxygen in SIPOS film were also discussed.

Objectives Coronary heart disease is one of the leading causes of mortality in women and men in the world. Aspirin use for the primary and secondary prevention of coronary heart disease reduces the risk of cardiovascular events. However, it appears that aspirin’s antiplatelet effect may not be uniform in all patients. Clinical aspirin resistance has included patients who, despite being on therapeutic doses of aspirin, experience thrombotic or embolic vascular events. Therefore, it is very important to identify high risk population who are more likely to develop aspirin resistance and then to conduct interventions at early stage. Methods To establish the prediction models, 1130 patients with stable angina who take aspirin (75-100 mg) for more than 2 months were included. Platelet aggregation was measured by light transmission aggregometry (LTA) and thrombelastography platelet mapping assay (TEG). And ROC approach of the interviewees to define the best cut point of the model with its sensitivity and specificity was applied. Results Seven risk factors were included in the model. Risk score was finally set up according to the coefficient B and rank of variables in logistic regression model (logit = exp (B 0 + B1X1 + B2X2 + … + BnXn). Our risk model showed good calibration and discriminative power in which Hosmer-Lemeshow test’s P value were greater than 0.05 and the area under the ROC curve were greater than 0.70. Results in our risk score: serum creatinine>110 umol/l: 1 score, fasting blood glueose>7.0 mmol/L:1 score, hyperlipidemia: 1 score, number of coronary artery lesion (2 branches:2 score, ≥3branches; 4 score), Body mass index: 20-25 kg/m 2 :2 score; >25 kg/m 2 : 4 score). PCI: 2 score, smoking: 3 score. Conclusions High levels of serum creatinine, fasting blood glucose and blood lipid, number of coronary artery lesion (2 branches:2 score, ≥3branches; 4 score),high body mass index and PCI history are risk factors for aspirin resistance. The incidence prediction model of aspirin resistance is effective to identify high risk population.

We report stable narrow linewidth laser systems based on self-developed Littman configuration external cavity diode lasers (ECDLs). The frequency of the ECDL is stabilized to a high fineness ultralow-expansion glass reference cavity with the Pound-Drever-Hall technique. By heterodyne beating of two identical systems, we conclude that the linewidth of each ECDL is reduced to lower than 150 Hz and its frequency stability reaches 4.3 × 10-14 at an averaging time of 1s, the averaged long-term frequency drift is less than 0.2 Hz/s over 30 h measurement time.

This paper reports that highly transparent and low resistance tantalum-doped indium tin oxide (Ta-doped ITO) films contacted to p-type GaN have been prepared by the electron-beam evaporation technique. The Ta-doped ITO contacts become Ohmic with a specific contact resistance of ~ 5.65 × 10−5 Ωcm2 and show the transmittance of ~98% at a wavelength of 440 nm when annealed at 500 °C. Blue light emitting diodes (LEDs) fabricated with Ta-doped ITO p-type Ohmic contact layers give a forward-bias voltage of 3.21 V at an injection current of 20 mA. It further shows that the output power of LEDs with Ta-doped ITO contacts is enhanced 62% at 20 mA in comparison with that of LEDs with conventional Ni/Au contacts.

For heating the tokamak plasma effectively, the ion source must be capable of producing ions with high proton ratio. The proton ratio, which is found to be more than 65.6% at the ion current of 19.6 A with the extraction voltage of 39.6 kV, is measured with an image spectrograph by Doppler shift effect of Balmer-α-radiation spectrum emitted from fast hydrogen particles. The tendency of proton ratio with the ion density in experiment is almost the same as the mode devised by Zhang et al. Okumura et al. only gave the affection of the plasma volume and ion loss area on the proton ratio, but the relationship between the ion density in chamber and the proton ratio was not presented. We give the relationship.

Ultrafast electron diffraction (UED) is a rapidly advancing technique capable of recording the atomic-detail structural dynamics in real time. We report the establishment of the first UED system in China. Employing this UED apparatus, both the coherent and the concurrent thermal lattice motions in an aluminium thin-film, trigged by ultrafast laser heating, have been observed. These results demonstrate its ability to directly measure a sub-milli-angstrom lattice spacing change on a sub-picosecond time scale.

We have demonstrated a stimulated photoluminescence (PL) at 694 and 692nm whose emission peak has a Lorentzian shape with a full width at half maximum of 0.5–0.6nm. This stimulated emission comes from the nanostructures on porous silicon oxidized fabricated by irradiation and annealing treatment. Controlling the time of annealing can produce a good coherent emission. A model has been proposed for explaining the stimulated emission in which the trap states of the interface between oxide of silicon and porous nanocrystal play an important role. Calculation shows that trap electronic states appear in the energy gap of the smaller nanocrystal when SiO bonds or Si–O–Si bonds are formed. In the theoretical model, the most important factor in the enhancement and pinning effect of PL emission is the relative position between the level of the trap states and the level of the photoexcitation in the silicon nanocrystal.