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The Upper Triassic Chang 8 Member, the eighth member of the Yanchang Formation, is a key reservoir interval in the Jiyuan area of the Ordos Basin. The reservoir quality of the Chang 8 Member tight ...

Bioassays were conducted in a greenhouse at 18°C to determine the effectiveness of a seed treatment used in combination with biocontrol agents for the reduction of corn damping-off caused by species of Pythium and Fusarium. Corn seeds were infiltrated with tap water, drained, air-dried, and then coated with biomass of an antagonistic fungus, Gliocladium virens isolate Gl-3, or an antagonistic bacterium, Burkholderia cepacia isolates Bc-B or Bc-1, or a combination of Gl-3 with each of the bacterial isolates. A nonsterile field soil was infested with a combination of pathogens: Pythium ultimum, P. arrhenomanes, and Fusarium graminearum at 2 inoculum rates (1× and 4×). Pre-infiltration enhanced (P ≤ 0.05) disease control with most treatments at both inoculum rates. Treatments with biocontrol agents alone or in combination, as well as the fungicide captan, effectively reduced the disease at a pathogen inoculum rate of 1×, resulting in greater (P ≤ 0.05) seedling stands, plant height, and fresh weight, and lower (P ≤ 0.05) root rot severity compared with untreated seeds in infested soil. At a pathogen inoculum rate of 4×, stands were lower (P ≤ 0.01) and root-rot severity was higher (P ≤ 0.01) compared to those at 1× for all treatments. Nevertheless, coating seeds with all biocontrol agents (alone or in combination), except with Bc-1 alone, reduced disease (P ≤ 0.05) compared to untreated seeds in infested soil. At both inoculum rates of 1× and 4×, coating seeds with Gl-3 + Bc-B was more effective (P ≤ 0.05) in disease control than any other treatment, resulting in stands, growth rate (plant height and fresh weight), and root rot severity similar to plants from untreated seeds in noninfested soil. In addition, when the exudate from a 2-h infiltration of corn seed was added to the seeds during seed coating, seedling stand was often lower and root rot severity was often higher than those from infiltrated seeds (P ≤ 0.05). These results indicated that the infiltration process removed certain exudates, including nutrients and/or stimulants (not detected in this study) that might be utilized by pathogens to initiate seed infection. A thin-layer chromatography (TLC) profile of the exudates showed the presence of eight amino acids and three major carbohydrates.

In this paper, the silicon volatilisation phenomenon during slagging by limestone in basic oxygen furnace (BOF) and its influencing factors were studied by industrial experiment and thermodynamic calculation. In our estimation, the volatilisation ratio of silicon in this industrial experiment is about 13.01–47.82%. Thermodynamic analysis showed that the silicon volatilisation phenomenon happens after charging limestone directly into BOF because CO2 from limestone decomposition could massively oxidise the silicon in the hot metal into gaseous SiO in the hot spot zone. The mass of produced SiO increases, then decreases with the increase of the limestone addition and the carbon content of hot metal, and SiO mass is proportional to silicon content of hot metal. Compared with lime slagging, the strong stirring effect of CO2 from limestone decomposition, massive foaming slag formation, great increment of furnace gas are all favourable to silicon volatilisation.

Recently MoSi2 sacrificial particles embedded in yttria partially stabilized zirconia (YPSZ)have been proposed as attractive healing agents to realize significant extension of the lifetime of the thermally loaded structures. Upon local fracture of the YPSZ, the embedded healing particles in the path and in the vicinity of the crack react with the oxygen atoms transported via the crack and first fill the crack with a viscous glassy silica phase (SiO2). The subsequent reaction between this freshly formed SiO2 and the existing tetragonal ZrO2 of the YPSZ leads to the formation of rigid crystalline zircon (ZrSiO4), which is key in the crack-healing mechanism of YPSZ based materials. The isothermal kinetics of the self-healing reaction and the mechanism of zircon formation from the decomposing MoSi2 and the surrounding YPSZ were assessed via X-ray diffraction (XRD). The obtained results revealed that at 1100 °C the reaction between amorphous SiO2 and YPSZ is completed after about 10 h. For a more accurate determination of the kinetics of the self-healing reaction, bilayer samples of YPSZ – MoSi2 (with and without boron addition)were annealed in air over a temperature range of 1100–1300 °C. This led to the formation of a MoSi2/amorphous (boro)silica/zircon/YPSZ multi-layer, which was investigated with scanning electron microscopy (SEM)and electron probe X-ray microanalysis (EPMA). Kinetic modeling of the growth of zircon and silica or borosilicate layers showed that zircon growth was dominated by the diffusion of Si4+ in zircon whereas the growth of the silica or borosilicate layer was controlled by oxygen diffusion. Moreover, a significant increase in the rate of ZrSiO4 formation was observed due to the presence of B in the MoSi2 particles.

High activity is one of the primary requirements for the catalysts in proton exchange membrane fuel cell applications. Platinum (Pt) is the best-known catalyst especially for oxygen reduction at the cathode; however, further activity improvements are still required. Previous computational studies suggested that the catalytic activity of Pt nanoparticles could be enhanced by a Pt−carbon support interaction. We have recently found that an enhanced electronic interaction occurs at the interface between an argon-ion (Ar+)-irradiated glassy carbon (GC) surface and Pt nanoparticles. Here, we report a more than two-fold increase in specific activity (SA) for the Pt nanoparticles on the Ar+-irradiated GC substrate compared to that on the non-irradiated GC substrate. The mechanism of this activity enhancement was investigated by local structure analysis of the interface. Ar+ irradiation of the carbon support led to the formation of the Pt−C bonding, thus protecting the deposited Pt nanoparticles from oxidation.

Directly charging limestone into slag in BOF is a newly emerging technique which broke through the traditional BOF slagging principle. It is necessary to study the decomposition behavior of limestone in converter slag during BOF steelmaking. FeO x , SiO2, MnO x and pre-melting slags were mixed with limestone according to different quality proportion to simulate the environment of limestone in converter slag. TG-DTA results indicated that slag with individual component, including FeO x , SiO2 and MnO x , all had obvious effects on reducing the decomposition temperature of limestone. Pre-melting slags with multiple components had further reducing effects than individual component. XRD results showed converter slag component would react with decomposition product of CaCO3 and generate solid solution or oxide, reducing the activity of CaO and the decomposition temperature of CaCO3.

Transition metal oxide heterostructures and interfaces host a variety of exciting quantum phases and can be grown with atomic-scale precision by utilising the intensity oscillations of $in$ $situ$ reflection high-energy electron diffraction (RHEED). However, establishing a stable oscillation pattern in the growth calibration of complex oxides films is very challenging and time consuming. Here, we develop a substantially more efficient and reliable growth calibration method for complex oxide films using molecular beam epitaxy., Comment: 4 pages, 3 figures

Chromium boride is characterized by interesting properties, like high melting point, hardness, and corrosion and abrasion resistances. In this paper a novel synthesis of chromium boride micropaticles via a solid-state route at 600 °C is reported. The X-ray diffraction pattern taken from the reaction product indicated that the product was orthorhombic chromium boride. The CrB particle size (about 1~2 μm) is confirmed by FESEM and TEM images. Solid state reactions that were carried out in sealed autoclave systems provide an alternative, convenient, and environmentally friendly pathway for the fabrication of CrB. Повідомляється про новий твердотільний метод синтезу при 600 °C борида хрому CrB, який характеризується такими цікавими властивостями, як високі температура плавлення і твердість, опір корозії і абразивного зносу. Діаграма рентгенівської дифракції продукту реакції свідчила про те, що продукт є орторомбическим боридом хрому. Розмір (~ 1–2 мкм) частинок CrB підтверджується FESEM і ТЕМ-зображеннями. Твердотільні реакції, проведені в герметичних автоклавах, забезпечили альтернативний, зручний, екологічно чистий шлях виробництва CrB. Сообщается о новом твердотельном методе синтеза при 600 °C борида хрома CrB, который характеризуется такими интересными свойствами, как высокие температура плавления и, твердость, сопротивление коррозии и абразивному износу. Диаграмма рентгеновской дифракции продукта реакции свидетельствовала о том, что продукт представляет собой орторомбический борид хрома. Размер (~ 1–2 мкм) частиц CrB подтверждается FESEM- и ТЕМ-изображениями. Твердотельные реакции, проведенные в герметических автоклавах, обеспечили альтернативный, удобный, экологически чистый путь производства CrB.

The trend in DNA-binding affinities and the spectral properties of a series of Ru(II) polypyridyl complexes, [Ru(bpy) 2 (dmdpq)] 2+ ( 1 ), [Ru(bpy) 2 (dpq)] 2+ ( 2 ), [Ru(bpy) 2 (cndpq)] 2+ ( 3 ) (bpy = 2,2′-bipyridine; dpq = dipyrido[3,2-d:2′,3′-f]quinoxaline; dmdpq = di-methyl-dpq; dcdpq = di-cyano-dpq), have been experimentally and theoretically investigated. The DNA-binding constants K b of the complexes were determined systematically with spectrophotometric titration. The density functional theory (DFT) and time-dependent DFT (TDDFT) calculations were carried out for these complexes. The experimental results show that these complexes bind to DNA in intercalation mode, and the order of their intrinsic DNA-binding constants K b is K b ( 1 ) K b ( 2 ) ≪ K b ( 3 ). The substituents on the intercalative ligands of the complexes play a very important role in the control of DNA-binding affinities of the complexes, in particular, the stronger electron-withdrawing substituent (–CN) on the intercalative ligand can greatly improve the DNA-binding property of the derivative complex. The trend in DNA-binding affinities as well as the spectral properties of metal–ligand charge-transition ( 1 MLCT) of this series of complexes can be reasonably explained by applying the DFT and TDDFT calculations and the frontier molecular orbital theory.

Liquid-phase siliconizing method is proposed to improve the oxidation resistance of the TiAl-based alloy. The expected effect was obtained on the siliconizing condition of 780 °C/10 min + 680 °C/10 min using Al–10 wt.%Si alloy. The presence of the compounds Ti 5 Si 3 and Al 12 Si 3 Ti 5 was identified by TEM in the siliconized layer, and the formation mechanism was elucidated from the thermodynamical point of view.

We present plane strain simulations about the dependence of orientational in-grain subdivision and crystallographic deformation textures in aluminum polycrystals on grain interaction. The predictions are compared to experiments. For the simulations we use a crystal plasticity finite element and different polycrystal homogenization models. One set of finite element simulations is conducted by statistically varying the arrangement of the grains in a polycrystal. Each grain contains 8 integration points and has different neighbor grains in each simulation. The reorientation paths of the 8 integration points in each grain are sampled for the different polycrystal arrangements. For quantifying the influence of the grain neighborhood on subdivision and texture we use a mean orientation concept for the calculation of the orientation spread among the 8 originally identical in-grain orientation points after plastic straining. The results are compared to Taylor–Bishop–Hill-type and Sachs-type models which consider grain interaction on a statistical basis. The study reveals five important points about grain interaction. First, the consideration of local grain neighborhood has a significant influence on the reorientation of a grain (up to 20% in terms of its end orientation and its orientation density), but its own initial orientation is more important for its reorientation behavior than its grain neighborhood. Second, the sharpness of the deformation texture is affected by grain interaction leading to an overall weaker texture when compared to results obtained without interaction. Third, the in-grain subdivision of formerly homogeneous grains occurring during straining is strongly dependent on their initial orientation. For instance some crystals build up ingrain orientation changes of more than 20° after 95% straining while others do practically not subdivide. Fourth, the dependence of in-grain subdivision on the neighbor grains is different for crystals with different initial orientation (cube or rotated Goss grains reveal strong subdivision). Fifth, the upper bound for the variation of texture due to changes in grain neighborhood amounts at most to 5% in terms of the positions of the main texture components. In terms of the overall orientation density all predictions (using different neighborhood configurations) remain within a narrow tube with an orientation scatter of 10% (β-fiber) to 20% (Brass component, α -fiber)) when the neighborhood changes.  2002 Acta Materialia Inc. Published by Elsevier Science Ltd. All rights reserved.

Self-assembly of n-heptadecane (n-C17H36) and n-hexatricontane (n-C36H74) was studied by means of scanning tunneling microscopy. A droplet of a solution of n-C17H36 containing 0.6 wt % of n-C36H74 formed an ordered binary alkane monolayer on the herringbone Au(111) surface, which was composed of 30% n-C36H74 and 70% n-C17H36. The alkane molecules were arrayed in parallel to the [011] azimuth, and their intermolecular distance was 0.48 nm, which is equal to the distance of solid alkanes. In contrast, the alkane monolayer formed on a highly oriented pyrolytic graphite (HOPG) surface was predominantly composed of an n-C36H74 layer including only ca. 3% of n-C17H36 as an impurity. The n-C36H74 molecules on the HOPG surface were compressed along the molecular axis and in the perpendicular direction to the molecular axis. It is deduced that the intermolecular interaction is optimized when the surface structure is profitable for self-assembly of alkanes where no strong alkane−surface interaction is required.

In this study, a cylindrical glass tube for near-field electrospinning (NFES) with multi-spinnerets is modified to fabricate polyvinylidene fluoride (PVDF) nanofibers on polyethylene terephthalate (PET) in large area. For the process, the traditional NFES is replaced by micro-drills technology which is used to design multi-spinnerets and drill spinnerets on the solder balls. PVDF solutions were formulated with 18 wt % and 44.2 μS/cm of the conductivity. When the electric field of 1.6 × 10 7 V/m overcomes the surface tension, the Taylor cone can be formed. After the surface tensions of the solution are overcome, PVDF piezoelectric fibers are spun from the Taylor cone tip and collected by the cylindrical glass tube at the tangential velocity of 1779.9 mm/s. Then, after the PVDF piezoelectric fibers were heated at 65°C for 1hour, PVDF fibers with higher piezoelectric β-phase crystallization can be obtained with diameters from 2 μm to 5 μm. Finally, PVDF piezoelectric fibers are packaged on parallel electrodes. By vibrating the fibers with frequency from 2~9 Hz, a maximum peak voltage of 86.9 mV can be observed. The wing of Bear Cicada was used to test the output voltage of PVDF fibers. The as-fabricated PVDF by multi-spinnerets can be applied to power scavenger, sensing devices, actuators, and biomedical purposes in the future.

Biocontrol of soilborne diseases of tomato caused by Rhizoctonia solani and Pythium ultimum alone or in combination with Sclerotium rolfsii and Fusarium oxysporum f. sp. lycopersici were studied in the greenhouse and field. Soilborne diseases of pepper caused by the first three pathogens were also studied alone or in combination with Phytophthora capsici. Tomato and pepper seeds were treated with biomass of Gliocladium virens (Gl-3) and Burkholderia cepacia (Bc-F), individually and in combination, and planted in pathogen-infested soilless mix. Seedling stands for tomato from treated seeds were comparable to that in non-infested soilless mix. Although seed treatments with individual biocontrol agents reduced damping-off in peppers, only the Gl-3 + Bc-F treatment resulted in stands similar to the non-infested control. When healthy seedlings of both crops were transplanted into pathogen-infested soil/soilless mix in the greenhouse, and supplementary root drenches of suspensions of Gl-3, Bc-F, and Gl-3 + Bc-F were applied, the plant fresh weight was significantly greater and the disease severity (DSI) significantly less than for infested controls. When transplants were set out into infested field plots, the combined Gl-3 + Bc-F application resulted in greater fresh weight and lower DSI for pepper, and greater fruit yield for tomato than those obtained with either Gl-3 or Bc-F alone.

© 2014 IEEE. A versatile silicon-based ultrasonic nebulizer that utilizes a twin-nozzle of multiple Fourier horns at 1-2 MHz drive frequencies has been realized to perform simultaneous aerosolization of cobinamide and magnesium thiosulfate drug solutions. The drive frequency of the individual nozzle for a desirable aerosol diameter was individually designed. Using the 2.0 MHz 4-Fourier horn twin-nozzle aerosols of the two drug solutions with mass median diameter (MMD) of 3.0±0.1μm and geometrical standard deviation (GSD) of 1.18±0.02 and total flow rate up to 400μL/min were produced.

Bioassays were conducted under greenhouse conditions to test the efficacy of antagonists applied to corn (Zea mays) seed for protection against seed rot and seedling damping-off at 18 and 25°C in a field soil artificially infested with a combination of Pythium ultimum, P. arrhenomanes, and Fusarium graminearum. Biomass of Gliocladium virens isolates Gl-3 or Gl-21, Trichoderma viride isolate Tv-1, or peat-based slurry of Burkholderia cepacia isolates Bc-B, Bc-T, or Bc-1 was coated individually onto corn seeds in one test, and Gl-3 or Bc-B at four inoculum levels was used in another test. Seed treatments with most of the biocontrol agents, as well as with the fungicide captan, significantly (P ≤ 0.05) increased seedling stand, plant height and fresh weight, and decreased root rot severity compared with untreated seeds in pathogen-infested soil. Coating seeds with the biocontrol fungus G. virens isolate Gl-3 was the most effective treatment, resulting in greater (P ≤ 0.05) seedling stand, plant height, and fresh weight, and lower (P ≤ 0.05) severity of root rot than those parameters from seeds treated with captan or other antagonists at both temperatures. The results from the seeds treated with Gl-3 were similar to those of untreated seeds in noninfested soil. In treatments with Bc-1, Bc-T, Bc-B, or Tv-1, incubation temperature affected plant emergence, root rot severity, plant height, and fresh weight (P ≤ 0.01). Conversely, in seeds coated with Gl-3 or Gl-21, these parameters were similar at both temperatures. The minimum number of propagules needed per corn seed to obtain plant emergence comparable to that from captan-treated seeds was between 104 and 105 CFU for Gl-3 and >108 for Bc-B. When propagules of Gl-3 were applied at a rate >106 CFU per seed, seedling emergence was greater (P ≤ 0.05) than that from captan-treated seeds.

In this paper, the influence of BOF converter slag on CaCO3 decomposition was studied by laboratory experiments. FeOx , SiO2 , MnOx and pre-melted slags were mixed with CaCO3 according to a predetermined proportion to simulate the environment of limestone in converter slag. TG-DTA results indicated that individual components of slag, including FeOx , SiO2 and MnOx , all had obvious effects on reducing the decomposition temperature of CaCO3 . Multiple components of pre-melted slags had further reducing effects than individual components. XRD results showed that converter slag components would react with decomposition product of CaCO3 and generate solid solution or oxide, reducing the activity of CaO and the decomposition temperature of CaCO3 . In the end, burned lime and natural limestone were mixed with pre-melted slag and TG-DSC results showed that limestone showed a stronger ability to react with pre-melted slag than burned lime does.

A 1.55 mum Ge islands resonant-cavity-enhanced (RCE) detector with high-reflectivity bottom mirror was fabricated by a simple method. The bottom mirror was deposited in the hole formed by anisotropically etching in a basic solution from the back side of the sample with the buried SiO2 layer in silicon-on-insulator substrate as the etch-stop layer. Reflectivity spectrum indicates that the mirror deposited in the hole has a reflectivity as high as 99% in the range of 1.2-1.65 mum. The peak responsivity of the RCE detector at 1543.8 nm is 0.028 mA/W and a full width at half maximum of 5 nm is obtained. Compared with the conventional p-i-n photodetector, the responsivity of RCE detector has a nearly threefold enhancement. (C) 2004 American Institute of Physics.

Sharp and strong room-temperature photoluminescence (PL) of the Si0.59Ge0.41/Si multiquantum wells grown on the silicon-on-insulator substrate is investigated. The cavity formed by the mirrors at the surface and the buried SiO2 interface enhances the PL emission and has a wavelength-selective effect on the luminescence. The peak position is consistent with the simulation result and independent of the exciting power, which indicates a strong cavity effect on the room-temperature PL.

The precipitation behavior of a high-purity Fe-1.03 wt.% Cu alloy during ageing at 650 °C has been investigated by transmission electron microscopy. The microstructure and the corresponding diffraction patterns of the {100}*, {110}* and {111}* reciprocal planes were analysed. A metastable phase with a B2-like structure was observed, which is quite different from the equilibrium copper phase shown in the Fe–Cu phase diagram. The formation mechanism of the B2-like structure is deduced based on the energetic point of view.

Two kinds of methods such as spontaneous nucleation from flux-free stoichiometric melt and CuO flux method have been used for the growth of Pb0.5Sr2.5Y1−xCaxCu2Oy single crystals. The morphologies, phases, and compositions occurring in the crystals grown from the two kinds of methods were compared systematically. Optimum conditions for the growth of larger 1212 phase single crystals are x =0.15, 0.25, and 0.35. The lattice parameters of the crystals with the 1212 phase were found to be increasing upon Ca doping. The resistivity behavior of the PbSrYCaCuO single crystals with the 1212 phase both in the state of as-grown and after extended annealings under various oxygen partial pressure was also discussed briefly.

The ability of CuSO4- and hypochlorite-oxidized LDL to promote cholesterol accumulation in macrophages was examined. Both CuSO4- and hypochlorite-oxidized LDL were rapidly metabolized by mouse peritoneal macrophages to a level approximately 10 times that observed for native LDL and both modified lipoproteins increased the accumulation of unesterified cholesterol. However when each modified lipoprotein was incubated with macrophages for 40h, only hypochlorite-oxidized LDL produced significant accumulation of cholesteryl esters, with levels approaching 85 micrograms/mg cell protein. This finding was verified by nile red staining. The cholesteryl ester content of cupric sulfate-modified LDL was found to be significantly decreased when compared to either native or hypochlorite-modified LDL promotes massive cholesteryl ester accumulation because the cholesteryl ester content of the LDL particle is preserved.

Detoxification of massive cyanide (CN) poisoning by inhalation of antidotes is recognized to be superior to intra venous (IV) or intra muscular (IM) treatment with regard to ease of administration, self-administration, and rapidity of onset. However, there are currently no effective, portable, high-throughput inhalers that can be produced in large quantities and distributed for such purpose. A hand-held inhaler has been realized using silicon-based ultrasonic nozzle to produce high-throughput of monodisperse cobinamide antidote solution for detoxification of CN poisoning in a rabbit model. © 2012 IEEE.

Monodisperse micron-sized aerosol is ideal for pulmonary drug delivery. This paper reports delivery of monodisperse aerosol of medicinal droplets generated by MHz ultrasonic nozzles using an anatomically realistic upper airway model. The MHz ultrasonic nozzle is fabricated using MEMS technology, and comprised of a piezoelectric drive section and a silicon resonator of multiple Fourier horns (see Fig. 1) [1]. The dissolved medication is pumped into a central channel (200×200 μm2) inside the nozzle and exits at the nozzle tip that vibrates longitudinally at the nozzle resonant frequency. The novel design of multiple horns facilitates generation of a column of monodisperse droplets at electric drive power as low as 15mW [1]. Monodisperse ethanol droplets 2.4 μm and water droplets 4.5 μm in diameter have been produced, respectively, using 1.5 MHz and 1.0 MHz nozzles. We used an aqueous solution of 25mg/ml (2.5wt%) β2-agonist (isoproterenol) for generation of monodisperse droplets using the 1.0 MHz ultrasonic nozzles. A yield of >54% (to the lower airways on total amount of inhaled isoproterenol basis), significantly higher than the reported highest lower airways deposition (32%) using metered-dose-inhalers (MDIs) [2], has been accomplished.

This paper reports production of 4.5 μm-diameter monodisperse water droplets using silicon-based one MHz ultrasonic nozzles of a novel design. The novel design of multiple Fourier horns in resonance facilitates pure capillary wave mechanism atomization. The measured drop diameters are in very good agreement with those predicted by the capillary wave atomization mechanism. Due to the resonance effect, the power and voltage requirements for atomization were as low as 15 mW and 6.5 V at atomization rate as high as 300 μl/min. The droplet diameter was reduced to 4.1 μm when the surface tension of the liquid was reduced from 70 dyne/cm (water) to 50 dyne/cm (0.25% Triton X-100 surfactant solution). Such small diameter drops with GSD (geometrical standard deviation) as small as 1.1 was achieved in ultrasonic atomization for the first time. Note that the fraction of all particles smaller than 5.8 μm in diameter represents the inhaleable fine particle fraction and GSD of 1.3 or smaller is commonly accepted as the standard for monodispersity. Therefore, the MEMS-based MHz ultrasonic nozzle should have very significant impacts on targeted delivery of reproducible doses of medicine to the respiratory system.Copyright © 2008 by ASME

In situ Raman spectra of SiHx, Si–F, and Si–Si vibrations from Si surfaces in HF aqueous solutions are obtained using a highly sensitive confocal microprobe Raman system. Electrochemical roughening pretreatment and laser-assisted roughening procedure enable good quality surface Raman spectra to be obtained. The surface Raman and photoluminescence spectra from the Si surface in the etching environment and the correlation of the two types of spectra are discussed. The Raman spectroscopy is shown to have high potential in serving as an important tool for in situ investigating of Si surface bonding during the etching process.

On the basis of previous studies, this paper provides a preliminary summary of recent research on mafic-ultramafic intrusions and related magmatic Cu-Ni sulfide ore deposits in northern Xinjiang. The authors argue that there is still a need to study some key problems concerning the origin and tectonic settings of these intrusions and sulfide deposits.

The structural phase transition and local structural distortion of Er-doped BiFeO3 nanoparticles have been discussed in order to understand the variation of magnetic properties in this system. The X-ray diffraction patterns and X-ray absorption fine structure of these samples demonstrate that there is structural phase transition and no obvious local structural distortion with the increasing of doping concentration. Unfortunately, no ferromagnetic properties have been observed even at a lower temperature. And the X-ray absorption spectra of Fe 2p core level of these samples are totally same, especially the energy positions do not shift which means the consistent valence states of Fe ions.

The effect of nano-segregation phases formed during rolling process on the electrochemical property of Al-Mg-Sn-Bi-Ga-In alloy anode in alkaline solution (80?C, Na2SnO3 + 5mol/L NaOH)was analyzed according to the chronopotentiometry (E-T curves), hydrogen collection tests and modern microstructure analysis. The results show that when controlling the rolling temperature and pass deformation at 370?C and 40% respectively, the Al alloy anode undergoes the dynamic recrystallization, which benefits to the uniform distribution of nano-segregation phases and improvement of electrochemical property of Al alloy anode. The optimum Al alloy anode has the more negative electrode potential of about -1.48V (vs.Hg/HgO) and the lower hydrogen evolution rate of 0.1889mL/ (min?cm2).

Porous nanomasks have been prepared in situ on an insulating silicon wafer by anodization of an aluminum film grown on it. Ultra-thin nanomasks, around 50 nm thick, were fabricated by utilizing a stop signal, a vivid color appearing at the air-electrolyte interface, and the process involved showed excellent repeatability. Finally, 2D nanoscale p-n junction arrays were fabricated on a silicon on insulator (SOI) wafer using the ultra-thin nanomasks prepared. The experimental results are in good agreement with the simulated results on the characteristics of the anodization process involved.

Interactions between platelets and fibrin are important in hemostasis but often confused with platelet-fibrinogen interactions. A stirred mixture of solubilized fibrin and washed platelets at neutral pH range showed drastic reduction in turbidity and concomitant platelet adhesion onto newly formed fibrin strands. This platelet-fibrin interaction did not require platelet activation nor did it cause platelet aggregation. A device consisting of a parallel-plate flow chamber mounted on a fluorescence microscope has been constructed to allow direct visualization and recording of platelet-fibrin interaction under flow conditions. Platelets in whole blood adhered to the fibrin-coated portion but not to the uncoated portion of the flow chamber. Slow motion playback of video tapes indicated that the adhesion phenomenon was a dynamic process that involved attaching, detaching, relocation and transient contact. The fibrin coating influenced platelet adhesion both by increasing the number of cells making short-term attachments to the surface and by increasing the duration of cells attached to the surface. These observations provided basic characteristics of platelet-fibrin interaction.

A Si resonant-cavity-enhanced (RCE) photodiode was fabricated on a silicon membrane. The Si membrane was formed by etching from the back side of the silicon-on-insulator substrate with the buried SiO2 layer as etch-stop layer. A gold layer was deposited serving as an electrode layer and bottom mirror of the RCE photodiode. The photodiode had an external quantum efficiency of 33.8% at the resonant wavelength of 848 nm and a full width at half maximum (FWHM) of 17 nm. The responsivity was 4.6 times that of a conventional Si p-i-n photodiode with the same absorption layer thickness. (c) 2005 American Institute of Physics.

A simple process for fabricating low-cost Si-based continuously tunable long-wavelength resonant-cavity-enhanced (RCE) photodetectors has been investigated. High-contrast SiO2/Si(Deltan similar to2) was employed as mirrors to eliminate the need to grow thick epitaxial distributed Bragg reflectors. Such high-reflectivity SiO2/Si mirrors were deposited on the as-grown InGaAs epitaxy layers, and then were bonded to silicon substrates at a low temperature of 350 C without any special treatment on bonding surfaces, employing silicate gel as the bonding medium. The cost is thus decreased. A thermally tunable Si-based InGaAs RCE photodetector operating at 1.3-1.6 mum was obtained, with a quantum efficiency of about 44% at the resonant wavelength of 1476 nm and a tuning range of 14.5 nm. It demonstrates a great potential for industry processes. (C) 2005 American Institute of Physics.

Surface enhanced Raman spectra (SERS) of adsorbed species from a bare cobalt (Co) bulk electrode were observed for the first time with confocal Raman microscopy. A combined AFM, Raman and electrochemical study shows that a proper roughening procedure is vitally important for obtaining good-quality surface Raman spectra from the Co electrode. The surface enhancement factor ranges from 2 to 3 orders of magnitude, depending critically on the surface roughening procedure. The present study provides a bright prospect for the wide investigation of systems of practical application.

A study has been made of the transpassive dissolution of mild steel in sodium nitrate solution over a range of current densities from 2 to 100 A cm−2. The dissolution current efficiency and the anode potential free from the electrolyte IR component were measured in a flow cell; optical and scanning electron microscopy were then used to examine the sample surfaces after the dissolution tests. The results show that during the early stage of transpassive dissolution, the mild steel is covered with a compact, electronically conductive Fe3O4 film, and the current is consumed mainly in oxygen generation on the film/electrolyte interface. With increasing anode potential and current density, this film is gradually broken and the underlying metal surface becomes exposed to the electrolyte. At this stage, iron dissolution begins at a high rate. The film rupturing process is strongly dependent on nitrate concentration; the higher this is, the lower is the current density required to rupture the film.

The following radicals have been identified in the liquid phase ..gamma.. radiolysis of several nitriles by spin trapping with phenyl tert-butyl nitrone: CH/sub 2/CN in acetonitrile, H and CH/sub 3/CHCN(question) in propionitrile, CH(CN)/sub 2/ in malononitrile, and H, CN, and CH/sub 2/CH/sub 2/CN in succinonitrile. ..gamma.. proton splittings are observed for the CH/sub 2/CN and CH(CH)/sub 2/ spin adducts. The results are discussed in comparison with solid phase radiolysis data and with alkyl radical spin adduct splittings.

The effect of up to 0·20 wt.-% additions of silver on the anodic corrosion of 4·5 wt.-% antimony–lead alloy, when corroded in sulphuric acid at potentials exceeding the PbO2/PbSO4 potential has been established. Silver reduces significantly both the rate and magnitude of corrosion in silver–antimony–lead alloys. The corrosion resistance of these alloys is shown to be concentration-dependent increasing with increase of silver content.Microstcuctures indicate. that in 4·5 wt.-% antimony–lead alloys, corrosion takes place by the selective dissolutwn of antimony-rich phase, which forms a continuous network in as-cast and a discontinuous network in homogenised–quenched alloys. Whereas, in silver–4·5 wt.-% antimony–lead alloys, corrosion takes place mostly by the oxidation of lead-rich phase and no preferential attack of the antimony-rich phase occurs zn homogenised–quenched alloys. An electron-beam microprobe has been used to establish the distribution and location of silver and antimony at, or in the ...

A diffusion model based on the simultaneous interdiffusion and reaction between alternate slabs of reactants is used to simulate the data of Vassilatos and Toor. After slab sizes are chosen to fit the conversion data for very rapid reactions in a stoichiometric mixture, reasonably good predictions are obtained of the effect of stoichiometry and reaction velocity constant on conversion. The results are close to the predictions of Kattan and Adler's stochastic mixing model, and the similar behavior of these disparate models implies that conversion is insensitive to the details of the mixing.

Eighteen primiparous mice in their 6th to 9th day of lactation were randomly divided into groups of six. Each group was assigned to one of the three milking intervals, .25, 4, and 12h. Blood flow was measured simultaneously in right and left abdominal mammary glands by Sapirstein's indicator fractionation technique with sodium 24 chloride as the indicator. Lactose was extracted from the same tissue and quantified by gas chromatography. Up to 4h, mammary blood flow was inversely related to the amount of milk accumulated in mammary gland. Around 4h blood flow started to level off and somewhere between 4 and 12h reached a maintenance rate. Rate of lactose synthesis was markedly reduced in this period. The relationship between mammary blood flow (Y) and lactose content (X) in the tissue was curvilinear, Y=4.43 − .83X + .06X 2 (correlation – .83).

Dilute alloys of lithium in lead have been investigated as possible grid alloys for use in lead-acid batteries. Cast grids can illustrate a time-dependent brittleness associated with mold temperature and alloy composition. For temperatures above theβ-to-β′ Li−Pb transformation, alloys exceeding room temperature solid solubility are initially ductile whereas samples tend to be brittle at temperatures below this transition. The nature of brittleness is discussed and the roles that the transformation occurring in the precipitate, coring, and grain boundary precipitation have in promoting brittleness are examined. It is shown that precipitation during aging contributes most to the embrittlement by formation of precipitate-free areas in the immediate vicinity of grain boundaries.