Glycerol steam reforming over calcium hydroxyapatite supported cobalt and cobalt-cerium catalysts

Calcium hydroxyapatite（HAp） supported cobalt and cobalt-cerium catalysts were examined for hydrogen production in glycerol steam reforming. The catalysts were synthesized by incipient wetness impregnation method and characterized through X-ray diffraction, adsorption-desorption isotherms of N2 and temperature-programmed reduction of H2. Catalytic properties were examined in terms of glycerol conversion, selectivity toward hydrogen and C-containing products in temperature range of 650-800 ℃.The effect of active metal reduction and residence time（thereby flow feed rate） was analysed. It was found that the growth of residence time increased the hydrogen selectivity in the whole temperatures range whereas the catalyst reduction, before the catalytic process, decreased the hydrogen selectivity at temperatures lower than 750 ℃. The cerium addition improved the catalytic behaviour for hydrogen production via glycerol steam reforming. Cerium oxide suppressed the sintering of cobalt particles and as a result Co-Ce/HAp ensured higher stability and H2 selectivity than Co/HAp. Under reaction conditions investigated in this study, the highest selectivity toward hydrogen at 650 ℃ was obtained for 7.5 Co-Ce/HAp catalyst.

Application of monodispersive anion exchangers in sorption and separation of Y^3＋ from Nd^3＋ and Sm^3＋ complexes with dcta

Rare earth complexes with trans-1,2-diaminocyclohexane-N,N,N ,N -tetraacetic acid （DCTA） of the Ln（dcta） type exhibited an unusual sequence of affinity on the polystyrene anion exchangers： pm^3＋〉Nd^3＋〉Sm^3＋〉Pr^3＋〉Ce^3＋〉Eu^3＋〉Gd^3＋〉La^3＋〉Sc^3＋〉Tb^3＋〉Dy^3＋〉 Ho^3＋〉Y^3＋〉Er^3＋〉Tm^3＋〉Yb3＋〉Lu^3＋[1]. Taking into account the position of Y^3＋, Sm^3＋, and Nd^3＋ in this affinity series, for the monodispersive polystyrene anion exchangers, Lewatit MonoPlus M 500, Lewatit MonoPlus M 600, Lewatit MonoPlus MP 500, Lewatit MonoPlus MP 64, and for the heterodispersive anion exchanger, Lewatit MP 62, the weight （Dg） and bed （Dv） distribution coefficients of these complexes and working ion exchange capacities （Cw） were determined. Based on these values, purifications of Y^3＋ from Nd^3＋ and Y^3＋ from Sm^3＋ in the macro-micro component system on these anion exchangers were studied. The application potential of this method was highlighted for the separation of Y^3＋ in the presence of Nd^3＋ and Sm^3＋. With 1 L of monodispersive and strongly basic polystyrene gel anion exchanger Lewatit MonoPlus M 500 in the acetate form, it is possible to obtain approximately 79 g Y2O3 purified from Nd2O3 and 70 g Y2O3 purified from Sm2O3 in the same process condition.

Contamination of Lead and Mercury in Coal Basin of India

The coal is contaminated with toxic metals at the trace levels. They are released into the environment during mining, handling and burning of coal. The Korba basin has one of the largest coal exploitation areas in the country. In this work, contamination and sources of toxic metals i.e. Hg and Pb in the air, soil and sediment of the Korba basin, India are described. The concentration of Hg and Pb in the ambient air was ranged from 7.4 - 29 and 7.0 - 585 ng/m3 with mean value of 18 ± 4 and 129 ± 104 ng/m3 in the winter season. The mean concentration of Hg in the soil and sediment was 0.22 ± 0.03 and 0.44 ± 0.08 mg/kg, respectively. The higher concentration of Pb in the environmental samples was observed.

波兰东南部乌灰鹞在雏鸟出羽后期的同窝雏间冲突(英文)

通过对波兰东南部的13巢乌灰鹞(Circus pygargus) ,37只雏鸟观察,对同窝雏鸟间的竞争进行了研究。无论是在食物的数量或者生物量上,早孵出的雏鸟占有空中喂养与巢内喂养的食物源的绝对优势。空中学习捕食的食物量占喂养食物量的比例随着雏鸟年龄的增长而增加。雏鸟在空中喂养中的攻击行为通过对空中食物传递进行研究。在370次的食物传递中,由于雏间竞争而引起的落地食物的比例57次(7·8 %)。由于雏间竞争而不能获得亲鸟喂养的幼鸟有时捕食周围的雀形目小鸟。亲鸟很少喂养较小的雏鸟。窝雏数越大,雏鸟间对食物的争斗持续时间越长。空中食物传递中捕食的成功率与雏鸟的空间分布相关。这种建立在雏鸟早期的等级制一直持续到雏鸟的出羽后期,从而保证早出雏具备开始迁徙的良好身体条件[动物学报51 (5) : 790 -796 ,2005]。

Effects of Polar Organic Solvent on Separation of Y(edta)^-/Nd(edta)^- Complexes on Polyacrylic Anion Exchangers

The use of polar organic solvents for the separations of rare earth elements (Ⅲ) is effective especially for their extensive separations despite the solubility limitations. The study shows that polyacrylate anion exchangers, particularly the weakly basic, gel anion exchanger Amberlite IRA 68, can be applied to the separation of rare earth complexes with EDTA in H_2O-methanol and H_2O-ethanol systems. In most cases the determined distribution coefficients of Ln^(3+) complexes with EDTA in mixed media like water-methanol on polyacrylate anion exchangers are larger than those in pure water (media.)

波兰西南卢布林中部地区纵纹腹小鸮的繁殖期食性(英文)

2000、2001年4 -7月,我们对波兰东南部纵纹腹小( Athene noctua)繁殖期的食性进行了研究。通过对498个食丸的分析,检出了1 953类动物,其中昆虫占猎物总数量的60·5 % (生物量仅占2·7 %) ,且以鞘翅目(Coleoptera)昆虫居多。该地区纵纹腹小的主要食物是小哺乳动物(占总生物量的93·4 %和总数量的38·3 %) ,在4月出现了一个取食小哺乳动物的高峰。在所捕食的猎物中,个体最大的是欧鼹鼠(Talpa eu-ropaea) ( n=2)。研究还发现,纵纹腹小的猎物种类有季节性变化,以满足繁殖各阶段(如孵卵、育雏和饲喂离巢幼鸟)不同的能量需求。

Contamination of Pond Water and Sediment in Coal Burning Area

The pond water is used by a variety of animals i.e. mammals, birds, duck, and fish. Sediments play a significant role in determining the overall environmental quality for the living organism. Therefore, in this work, chemical characterization of pond water and sediment in the largest coal burning basin of India i.e. Korba basin is described. Elements i.e. C, O, S, F, Cl, Na, Mg, Al, Si, P, K, Ca, Ti, Fe, As, Cr, Cu, Zn, Cd, Pb, and Hg were quantified. Toxic metals i.e. As, Cd, Hg, and Pb were highly enriched in the sediments, ranging from 36 - 154, 0.14 - 1.19, 0.12 - 0.82 and 26 - 127 mg/kg with mean value (p = 0.05) of 95 ± 12, 0.62 ± 0.11, 0.35 ± 0.08 and 75 ± 13 mg/kg, respectively. The concentration variations, pollution indices and sources of elements in water and sediment are discussed.

Sewage Pollution in Central India

Raipur is a fast growing city in central India due to being commercial centre for the steel, cement and forest products of the country. Large quantity (≈300 million lit/day) of untreated sewage waste water is discharged into seven reservoirs located in the city. Sewage carries excessive nutrients, heavy metals, organics, bacteria, yeast and fungi by leaking contents into the drinking water which cause acute health problems, ranging from common diarrhoea to deadly diseases such as hepatitis, cholera, typhoid fever, etc. Therefore, in this work, the microbial and chemical contamination of sewage waste of Raipur city, Chhattisgarh, India is described.

Why Do the Main Sequence Stars Have Similar Chemical Composition?

In this short note we have reconsidered the Jeans criterion for gravitational contraction of a gas nebula at different temperatures, from the present-day background radiation temperature (2.8 K) to those which existed at the early stage of the Universe. We demonstrate that the initial mass of quasars cannot be of the order of single galaxy masses, but rather 106 solar mass only. If they have larger masses, it must be the result of subsequent accretion process. Nevertheless quasars, formed prior to the stars, were the immediate source of the elements heavier than helium.

Synthesis and Properties of Fumed Silicas Modified with Mixtures of Poly(methylphenylsiloxane) and Dimethyl Carbonate

Effect of the concentration ratios of organosiloxane/initiator and treatment temperature on the characteristics of hydrophobic products obtained by modification of surface of fumed silica with poly(methylphenylsiloxane) (PMPS) in the presence of dimethyl carbonate has been studied. Morphology, particle size, surface area and coating microstructure of modified silicas were analyzed by methods of transmission electron and atomic force microscopies, nitrogen adsorption-desorption data. Carbon contents in the grafted modifying layer of organosilicas were determined using IR spectroscopy and elemental analysis. Hydrophilic-hydrophobic properties of surface of the obtained modified silicas were estimated by measurements of contact angles of wetting. It was shown that modification of pyrogenic silicas with mixtures of poly(methylphenylsiloxane) and dimethyl carbonate allows to obtain the homogeneous hydrophobic products and serve their nanodispersity.

Characterization of Urban Soil with SEM-EDX

The coal is largely used for generation of energy in the India, and their huge exploitations cause contamination of the soil. In the present work, the inorganic contamination of surface soil in the coal basin of the country, Korba is described. The concentration of elements i.e. C, O, S, Cl, Na, Mg, Al, Si, P, K, Ca, Ti, Fe, Mn and Ni in the surface soils (n = 30) was analysed by technique i.e. scanning electron microscope-energy dispersive X-ray spectroscopy (SEM-EDX), ranged from 6.6% - 36.4%, 37.8% - 54.3%, 0.07% - 0.39%, 0.03% - 0.25%, 0.10% - 0.39%, 0.12% - 0.49%, 3.7% - 10.3%, 12.2% - 24.4%, 0.11% - 0.60%, 0.68% - 3.22%, 0.8% - 2.7%, 0.25% - 0.61%, 2.3% - 6.4%, 0.08% - 0.22% and 0.04% - 0.16% with mean value (p = 0.05) of 18.8% ± 2.7%, 49.0% ± 1.5%, 0.18% ± 0.03%, 0.11% ± 0.02%, 0.23% ± 0.03%, 0.32% ± 0.03%, 6.1% ± 0.5%, 16.9% ± 0.9%, 0.27% ± 0.04%, 1.6% ± 0.2%, 1.5% ± 0.2%, 0.41% ± 0.03%, 4.3% ± 0.4%, 0.14% ± 0.02% and 0.08% ± 0.01%, respectively. The surface soil morphology, concentration variation of elements, pollution indices and contaminant sources in the soil are discussed.

Immunity of the greater wax moth Galleria mellonella

Investigation of insect immune mechanisms provides important information concerning innate immunity, which in many aspects is conserved in animals. This is one of the reasons why insects serve as model organisms to study virulence mechanisms of human pathogens. From the evolutionary point of view, we also learn a lot about host-pathogen interaction and adaptation of organisms to conditions of life. Additionally, insect-derived antibacterial and antifungal peptides and proteins are considered for their potential to be applied as alternatives to antibiotics. While Drosophila melanogaster is used to study the genetic aspect of insect immunity, Galleria mellonella serves as a good model for biochemical research. Given the size of the insect, it is possible to obtain easily hemolymph and other tissues as a source of many immune-relevant polypeptides. This review article summarizes our knowledge concerning G. mellonella immunity. The best-characterized immune-related proteins and peptides are recalled and their short characteristic is given. Some other proteins identified at the mRNA level are also mentioned. The infectious routes used by Galleria natural pathogens such as Bacillus thuringiensis and Beauveria bassiana are also described in the context of host-pathogen interaction. Finally, the plasticity of G. mellonella immune response influenced by abiotic and biotic factors is described.

Host-pathogen interaction after infection of Galleria mellonella with the filamentous fungus Beauveria bassiana

The filamentous fungus Beauveria bassiana is a natural pathogen of the greater wax moth Galleria mellonella.Infection with this fungus triggered systemic immune response in G.mellonella;nevertheless,the infection was lethal if spores entered the insect hemocel.We observed melanin deposition in the insect cuticle and walls of air bags,while the invading fungus interrupted tssue continuity.We have shown colonization of muscles,air bags,and finally colonization and complete destruction of the fat body-the main organ responsible for the synthesis of defense molecules in response to infection.This destruction was probably not caused by simple fungal growth,because the fat body was not destroyed during colonization with a human opportunistic pathogen Candida albicans.This may mean that the infecting fungus is able to destroy actively the insect's fat body as part of its virulence mechanism.Finally,we were unable to reduce the extremely high virulence of B.bassiana against G.mellonella by priming of larvae with thermally inactivated fungal spores.

Ultrabroadband wavelength-swept source based on total mode-locking of an Yb:CaF_(2)laser

We present an ultrabroadband, high-speed wavelength-swept source based on a self-modulated femtosecond oscillator. Photonic crystal fiber was pumped by a mode-locked Yb:CaF2 laser, resulting in a strong spectral broadening from 485 to 1800 nm. The pump laser cavity could be realigned in order to achieve total mode-locking of the longitudinal and transverse TEM00 and TEM01 electromagnetic modes. This led to spatial oscillations of the output beam, which induced modulation of the coupling efficiency to the fiber. Due to the fact that nonlinear spectral broadening was intensity dependent, this mechanism introduced wavelength sweeping at the fiber output. The sweeping rate could be adjusted between 7 and 21.5 MHz by changing the geometry of the pump cavity. By controlling the ratio of the transverse mode amplitudes, we were able to tune the sweeping bandwidth, eventually covering both the 1300 nm and 1700 nm bioimaging transparency windows. When compared with previously demonstrated wavelength-swept sources, our concept offers much broader tunability and higher speed. Moreover,it does not require an additional intensity modulator.

Novel synthesis method combining a foaming agent with freeze-drying to obtain hybrid highly macroporous bone scaffolds

Three-dimensional macroporous scaffolds are commonly used in bone tissue engineering applications since they provide sufficient space for cell migration and proliferation, facilitating bone ingrowth and implant vascularisation. The aim of this work was to combine two simple methods, freeze-drying and gas-foaming, in order to fabricate highly macroporous bone scaffolds made of chitosan/agarose matrix reinforced with nanohydroxyapatite. The secondary goal of this research was to comprehensively assess biomedical potential of developed biomaterials. In this work, it was demonstrated that simultaneous application of freeze-drying and gas-foaming technique allows to obtain hybrid(as proven by ATR-FTIR)macroporous bone scaffolds(pore diameter > 50 um) characterized by high open(70%) and interconnected porosity. Novel scaffolds were non-toxic, favoured osteoblasts adhesion and growth and induced apatite formation on their surfaces, indicating their high bioactivity that is essential for good implant osseointegration. Biomaterials were also prone to enzymatic degradation, degradation in acidified microenvironment(e.g. osteoclast-mediated), and slow degradation under physiological p H of 7.4.Moreover, the scaffolds revealed microstructure(70% open porosity, SSA approx. 30 m2/g, high share of macropores with diameter in the range 100-410 um) and compressive strength(1–1.4 MPa) comparable to cancellous bone, indicating that they are promising implants for cancellous bone regeneration.

All-in-fiber amplification and compression of coherent frequency-shifted solitons tunable in the 1800–2000 nm range

We report an all-fiber, all-polarization maintaining(PM) source of widely tunable(1800–2000 nm) ultrashort pulses based on the amplification of coherent self-frequency-shifted solitons generated in a highly nonlinear fiber pumped with an Er-doped fiber laser. The system delivers sub-100 fs pulses with energies up to 8.6 nJ and is built entirely from PM optical fibers, without any free-space optics. The all-fiber alignment-free design significantly increases the suitability of such a source for field deployments.

Generation of sub-100 fs pulses tunable from 1700 to 2100 nm from a compact frequency-shifted Er-fiber laser

We report generation of sub-100 fs pulses tunable from 1700 to 2100 nm via Raman soliton self-frequency shift.The nonlinear shift occurs in a highly nonlinear fiber, which is pumped by an Er-doped fiber laser. The whole system is fully fiberized, without the use of any free-space optics. Thanks to its exceptional simplicity, the setup can be considered as an alternative to mode-locked Tm-and Ho-doped fiber lasers.

The study of the interactions between graphene and Ge（001）/Si（001）

The interaction between graphene and germanium surfaces was investigated using a combination of microscopic and macroscopic experimental techniques and complementary theoretical calculations.Density functional theory （DFT） calculations for different reconstructions of the Ge（001） surface showed that the interactions between graphene and the Ge（001） surface introduce additional peaks in the density of states,superimposed on the graphene valence and conduction energy bands.The growth of graphene induces nanofaceting of the Ge（001） surface,which exhibits well-organized hill and valley structures.The graphene regions covered by hills are of high quality and exhibit an almost linear dispersion relation,which indicates weak graphene-germanium interactions.On the other hand,the graphene component occupying valley regions is significantly perturbed by the interaction with germanium.It was also found that the stronger graphene-germanium interaction observed in the valley regions is connected with a lower local electrical conductivity.Annealing of graphene/Ge（001）/Si（001） was performed to obtain a more uniform surface.This process results in a surface characterized by negligible hill and valley structures;however,the graphene properties unexpectedly deteriorated with increasing uniformity of the Ge（001） surface.To sum up,it was shown that the mechanism responsible for the formation of local conductivity inhomogeneities in graphene covering the Ge（001） surface is related to the different strength of graphene-germanium interactions.The present results indicate that,in order to obtain high-quality graphene,the experimental efforts should focus on limiting the interactions between germanium and graphene,which can be achieved by adjusting the growth conditions.

Surface and Subsurface Defects Studies of Dental Alloys Exposed to Sandblasting

The defects created in commercial dental alloys during blasting with alumina particles propelled in compressed air under pressure 0.1 and 0.4 MPa have been studied using positron annihilation spectroscopy, scanning electron microscopy and X-ray diffraction. It was observed that higher pressure causes the increase in roughness and damaged zone range. The type of defects was determined as vacancies on dislocations. The defect concentration decreases with the depth and depends on alloys' type and applied pressure. The Rutherford backscattering spectroscopy and variable energy positron beam studies indicate shallow alumina deposition in material and show that small pressure of 0.1 MPa is not enough to remove metal surface oxides completely in 60 s in all studied dental alloys.

Ⅲ-Ⅴ semiconductor nanocrystal formation in silicon nanowires via liquid-phase epitaxy

Direct integration of high-mobility III-V compound semiconductors with existing Si-based complementary metal-oxide-semiconductor （CMOS） processing platforms presents the main challenge to increasing the CMOS performance and the scaling trend. Silicon hetero-nanowires with integrated III-V segments are one of the most promising candidates for advanced nano-optoelectronics, as first demonstrated using molecular beam epitaxy techniques. Here we demonstrate a novel route for InAs/Si hybrid nanowire fabrication via millisecond range liquid-phase epitaxy regrowth using sequential ion beam implantation and flash-lamp annealing. We show that such highly mismatched systems can be monolithically integrated within a single nanowire. Optical and microstructural investigations confirm the high quality hetero-nanowire fabrication coupled with the formation of atomically sharp interfaces between Si and InAs segments. Such hybrid systems open new routes for future high-speed and multifunctional nanoelectronic devices on a single chip.