Solution of a hollow thick-wall cylinder subject to quadric function pressures and its limit when l→∞

Analytical solution of basic equations in any discipline, especially in engineering science, is important. The solution of a hollow thick-wall cylinder subject to variable pressures, which is in fact a solution to the spatial symmetric problem, has found wide applications[1]. But the pressure is not always distributed uniformly in engineering prac-tice. So it is very significant to get the solution of arbitrarily distributed pressures. Among various functions, the multinomial function is most …     

Melt-spun Al<Subscript>70−<Emphasis Type="Italic">X</Emphasis></Subscript>Si<Subscript>30</Subscript>Mn<Subscript><Emphasis Type="Italic">X</Emphasis></Subscript> (<Emphasis Type="Italic">X</Emphasis>=0, 3, 5, 7, 10) anode in lithium-ion batteries

Al_70−X Si₃₀Mn _X (X=0, 3, 5, 7, 10, mol%) ribbons were prepared by melt spinning. A supersaturated solid solution of Si and Mn in fcc Al and some microstructures consisting of nano grains were obtained. Some alloys with nano-sized grains exhibited high discharge capacities and favorable cycle properties. The capacity of more than 400 mAh/g could be obtained in melt-spun Al₆₇Si₃₀Mn₃ alloy after 20 cycles and more than 300 mAh/g after 40 cycles. Li/Si and Li/Al compounds in the anodes of pure Al and pure Si were not detected in Al-Si-Mn alloys inserted by Li. It is considered that the formation of the supersaturated solid solution and refinement of microstructures have prevented the alloys from the forming the compounds with superfluous Li. As a result, the electrochemical properties have been improved. Supported by the National Natural Science Foundation of China (Grant No. 50371066)     

Stability of <Emphasis Type="Italic">γ</Emphasis>′ multimodal microstructure in a Ni-based powder metallurgy superalloy

Multimodal size distribution of γ′ phase was obtained in a slow-cooling experiment following supersolvus solution treatment (1191°C). The morphology of the secondary γ′ particles exhibited splitting and protrusion instabilities. In the subsequent aging process (815°C), reverse coarsening was observed, i.e., the average precipitate size decreased with increasing aging time. Reverse coarsening slows the coarsening rate of the precipitates, increases the hardness of the alloy, and greatly improves the morphological stability of the γ′ phase.     

Preparation of immobilized <Emphasis Type="Italic">ɛ</Emphasis>-polylysine PET nonwoven fabrics and antibacterial activity evaluation

A novel antibacterial material (L-PET) was prepared by immobilizing ε-polylysine on polyethylene terephthalate (PET) nonwoven fabrics. Surface modifications of the fabric were performed by using a chemical modification procedure where carboxyl groups were prepared on the PET surface, a coupling agent was grafted, and the ε-polylysine was immobilized. Scanning electron microscopy (SEM) was used to analyze the surface morphology of the fabrics, while the toluidine blue method and X-ray photoelectron spectroscopy (XPS) were used to evaluate the grafting densities. The antibacterial activities of the L-PET were investigated by using the shaking-flask method. The electron micrographs showed that the surface of the blank PET and the modified fabrics did not change. The results of XPS analysis confirmed that ε-polylysine was successfully grafted onto the surface of PET. The results of the antibacterial experiments showed that L-PET fabrics had excellent antibacterial activity against Escherichia coli and Staphylococcus aureus, and that L-PET fabrics were stable in storage for at least two years.     

<Emphasis Type="Italic">Moral Enhancement</Emphasis> durch Neurochirurgie? Machbarkeit und ethische Vertretbarkeit

Problem

Several influential bioethicists propagate “moral enhancement”. Some argue that this is the only way to save humanity from its own demise. Since the suitability of medical moral enhancement has been challenged with empirical arguments, some bioethicists put the idea forward to use neurosurgery, particularly deep brain stimulation. The paper investigates two questions: (1) Is moral enhancement through neurosurgery feasible, and if yes, to what extent? (2) Is moral enhancement ethically justifiable, insofar it is possible?

Arguments

These ad hoc propositions refer to a handful of experimental brain surgeries in severely mentally disabled persons and to historical psychosurgery. The present proposals for neurosurgical moral enhancement might be appropriate for reducing aggressiveness or sexual drive, so that less self-control would be required for morally adequate behavior. Theoretically, it can be imagined that neurosurgical interventions could increase self-control; however, no evidence exists for this idea so far. According to Tanner and Christen’s model of moral intelligence, all interventions proposed could manipulate at the utmost one of five components of the moral intelligence, namely the moral resoluteness. None of the proposed interventions aims at the improvement of the other four components, namely the moral compass, the moral sensibility, the moral problem solving or the moral commitment.

Conclusion

Comprehensive moral enhancement cannot be effectuated by neurosurgery, neither by recent nor by proposed neurosurgical methods. At most, future closed-loop systems that automatically deregulate certain impulses might produce a moral-conform behavior. However, such a technically controlled moral-conform behavior could be acknowledged as moral behavior only within a utilitarian ethics.

     

Magnetism regulation of (In<Subscript>1−<Emphasis Type="Italic">x</Emphasis></Subscript>Fe<Subscript><Emphasis Type="Italic">x</Emphasis></Subscript>)<Subscript>2</Subscript>O<Subscript>3</Subscript> semiconductors prepared by sol-gel method

Fe doped In₂O₃ samples (In_1−x Fe _x )₂O₃ (x=0, 0.05, 0.1, 0.2 and 0.3) on glass substrate were prepared by sol-gel method. The XRD results demonstrate that the solubility of Fe ions in In₂O₃ matrix is around 20%, above which impurity phase can be observed. The transmittance of the samples with x=0, 0.05, 0.1 and 0.2 are above 80% in the visible region while the transimittance of the glass is 90%. The transmittance curves slightly red-shifts as x increasing. All of the samples except x=0 are ferromagnetic at room temperature. The highest saturation magnetization moment is reached in the sample x=0.2 with 330 emu/cm³, and the coercive force is 169 Oe which is also the largest in our samples. The results indicate that the addition of Fe ions could tune the structure, the ferromagnetism and optical property in the In₂O₃ matrix.     

Chitosan and <Emphasis Type="Italic">β</Emphasis>-cyclodextrin microspheres as pulmonary sustained delivery systems

Chitosan and β-cyclodextrin were used to prepare microspheres with theophylline for pulmonary delivery by spray drying method. The characteristics, mucociliotoxicity, permeation rate and drug release were studied. The drug entrapments of microspheres Ⅰ, Ⅱ and Ⅲ were from 35.70% to 21.09% and 13.33%, while yields and encapsulation efficiencies were higher than 45% and about 90% respectively. The microspheres possessed low tap densities （0.34-0.48 g/cm^3）, appropriate diameters （3.35-3.94 μm） and theoretical aerodynamics diameters （2.20-3.04 μm）. SEM images showed the microspheres were spherical with smooth or wrinkled surface surfaces. FT-IR demonstrated theophylline had formed hydrogen bonds with chitosan and fl-cyclodextrin. The microspheres could effectively reduce the ciliotoxicity and easy to penetrate the memberine. The in vitro release of the microspheres was related to the ratio of drug/polymer and microspheres Ⅱ had a prolong release, providing the release of 72.00% in 12 h. The results suggestes that chitosan/β-cyclodextrin microspheres Ⅱ are a promising carrier as sustained release for pulmonary delivery.     

Analysis of Mg content of Zn<Subscript>1−<Emphasis Type="Italic">x</Emphasis></Subscript>Mg<Subscript><Emphasis Type="Italic">x</Emphasis></Subscript>O film grown on sapphire substrates by plasma-assisted molecular beam epitaxy

The Mg content of Zn_1−x Mg _x O film grown on A-sapphire substrates by plasma-assisted molecular beam epitaxy is measured by inductively coupled plasma (ICP) and electronic probe microanalysis (EPMA). A theoretical model for analyzing the difference in the Mg content between Zn-rich and Zn-deficient conditions in the growth process is established, and the mathematical relation between Mg content and the temperature of the Mg cell is formulated under Zn-rich condition. The formula derived is proven to be correct by experiments.     

Synthesis and Photovoltaic Properties of A Dithieno[6,5-<Emphasis Type="Italic">b</Emphasis>:10,11-<Emphasis Type="Italic">b</Emphasis>′]-8H-Cyclopentyl[1,2-b:4,3-<Emphasis Type="Italic">b</Emphasis>′]Diphenanthrene based Donor-Acceptor Alternating Copolymer

A novel fused nonacyclic monomer of dithieno[6,5-b:10,11-b′]-8H-cyclopentyl[1,2-b:4,3-b′] diphenanthrene (DTCPDP) was synthesized by combining the structural features of ladder-type and multiple fused multi-cyclic aromatics. DTCPDP has a single sp3-hybridized carbon bridge between fused multi-cyclic aromatics. The copolymerization of DTCPDT with the electron accepting unit of 4,7-di(thiophen-2-yl)benzo[c][1,2,5]thiadiazole (DTBT) via Stille coupling afforded a novel donor-acceptor (D-A) alternating copolymer PDTCPDT-DTBT. The copolymer exhibited good chemical and thermal stabilities, with an optical band gap of 1.82 eV and a low-lying highest occupied molecular orbital (HOMO) energy level of -5.32 eV. When the copolymer was incorporated into polymer: fullerene (PC₇₁BM) blends to fabricate bulk heterojunction polymer solar cell devices, the devices exhibited a moderate maximum power conversion efficiency (PCE) of 5.90%.     

Novel wide band gap alloyed semiconductors, <Emphasis Type="Italic">x</Emphasis>(LiGaO<Subscript>2</Subscript>)<Subscript>1/2</Subscript>-(1−<Emphasis Type="Italic">x</Emphasis>)ZnO,and fabrication of their thin films

Oxide semiconductor alloys of x(LiGaO₂)_1/2-(1−x)ZnO were fabricated by the solid state reaction between β-LiGaO₂ and ZnO and rf-magnetron sputtering. For the solid state reaction, the wurtzite-type single phases were obtained in the composition range of x⩽0.38. The formation range of the alloys was wider than that of the (Mg_1−x Zn _x )O system, because the β-LiGaO₂ possesses a wurtzite-derived structure and approximately the same lattice constants with ZnO. The electrical resistivity and energy band gap of the 0.38(LiGaO₂)_1/2-0.62ZnO alloyed ceramic were 0.45 Ωcm and 3.7 eV, respectively, at room temperature. For the alloying by sputtering, the films consisting of the wurtzite-type single phase were obtained over the entire composition range of x(LiGaO₂)_1/2-(1−x)ZnO. The energy band gap was controllable in the range from 3.3 to 5.6 eV. For the as-deposited film fabricated using the 0.4(LiGaO₂)_1/2-0.6ZnO alloyed ceramic target, the energy band gap was 3.74 eV, and the electrical resistivity, carrier density and the Hall mobility at room temperature were 3.6 Ωcm, 3.4×10¹⁷ cm⁻³ and 5.6 cm² V⁻¹ s⁻¹, respectively.     

Structure and infrared radiation property of Co<Subscript>1−<Emphasis Type="Italic">x</Emphasis></Subscript>Zn<Subscript><Emphasis Type="Italic">x</Emphasis></Subscript>Fe<Subscript>2</Subscript>O<Subscript>4</Subscript> ferrites by XAFS analysis

Co_1−x Zn _x Fe₂O₄ ferrites were prepared by solid state reaction. The microstructure and performance were studied by X-ray diffraction, X-ray absorption fine-structure analysis and IRE-2 infrared radiant test. It is found that infrared radiance show a nonlinear change with x, exhibiting the infrared radiance of this material improved and the average radiance in the 8–14 μm waveband reached 0.91. The Co³⁺ and Zn²⁺ ions are found to occupy both tetrahedral and octahedral sites, and correspondingly, the fraction of Fe³⁺ ions in B-site decreases nonlinearly in ferrites. The lattice parameters are found to concern with Zn²⁺, and the activation energy deduces from crystal strain and crystal vibrate increases with content Zn²⁺. The redistribution of the Co³⁺ and Zn²⁺ ions between tetrahedral and octahedral sites is related to the providing a selective tetrahedral and octahedral sites infrared radiance of Co_1−x Zn _x Fe₂O₄ ceramics with increasing x.     

Pore structure of new composite adsorbent SiO<Subscript>2</Subscript>·<Emphasis Type="Italic">x</Emphasis>H<Subscript>2</Subscript>O· <Emphasis Type="Italic">y</Emphasis>CaCl<Subscript>2</Subscript> with high uptake of water from air

A new composite adsorbent SiO₂·xH₂O·yCaCl₂ which is composed of macro-porous silica gel and calcium chloride is introduced. In order to analyze its adsorption theory, adsorption and desorption isotherms, BET surface areas, pore volumes and average pore diameters of macro-porous silica gel and four composite adsorbent samples with different CaCl₂ content are measured using SEM and Asap2010 apparatus. From the adsorption isotherms, desorption isotherms and lag loops, it can be deduced that the main pore structure in macro-porous silica gel and the new composite adsorbent have two shapes: taper with one top open and taper or hyperbolic taper with both ends open. Based on the analysis of pore diameter distribution and lag loop, a sketch map showing calcium chloride filled in pore of macro-porous silica gel is presented. The adsorption isotherms at 25°C are measured. Experimental results show that the new composite adsorbent can adsorb more water than common adsorbents (macro-porous silica gel, micro-porous silica gel and synthetic zeolite 13X). In the light of the results of pore structure, adsorption isotherms and lyolysis phenomenon are analyzed.     

Stability control of steer by wire system based on <Emphasis Type="Italic">μ</Emphasis> synthesis robust control

The uncertainty influences may result in performance deterioration and instability to the steer by wire (SBW) system. Thus, it must make the control system keep robust stability from uncertainty, and have good robustness. In order to effectively restrain the interference and improve steering stability, this paper presents a μ synthesis robust controller based on SBW system, which considers the effect of model uncertainty and external disturbance on the system dynamics. Taking the ideal yaw rate tracking, interference suppression and excellent robustness as the control objectives, the μ synthesis robust controller is designed using linear fractional transformation theory to deal with the uncertainty. Then, it is testified through time domain and robustness simulation analysis. Simulation results show that the proposed controller can not only ensure robustness and robust stability of the system quite well, but improve handling stability of the vehicle effectively. The results of this study provide certain theoretical basis for the research and application of SBW system.     

Breite Einwilligung (<Emphasis Type="Italic">broad consent</Emphasis>) zur Biobank-Forschung – die ethische Debatte

Definition of the problem

Ethical aspects of biobanking research are receiving increasing attention in the literature. It is particularly controversial which model of consent should be implemented in research biobanks.

Arguments

This paper outlines the ethical controversy surrounding various models of consent into biobank-based research. Following a brief introduction of established consent models, it delineates the development of alternative approaches and discusses the ethical and regulatory challenges associated with these. Relevant ethical principles are highlighted.

Conclusion

The article concludes that there are good reasons to trial a combination of initial broad consent with consent to governance for future biobanking research in Germany.

     

Preparation of <Emphasis Type="Italic">γ</Emphasis>-methacryloxypropyl Trimethoxy Silane Cross-linked PDMS Membrane for Pervaporation Recovery of Butanol

The present study aimed to improve the pervaporation (PV) performances of polydimethylsiloxane (PDMS) membranes by using special cross-linkers. The γ-methacryloxypropyl trimethoxy silane (KH-570) cross-linked PDMS membranes were fabricated and characterized by FTIR, TGA, WCA, DSC, SEM, and swelling properties. Experimental results showed that the separation factor of the membrane increased slightly with the feed temperature whereas permeate flux increased. Butanol flux increased slowly with the feed concentration while the water flux decreased. The overall result indicated that the separation factor decreased slowly with the feed concentration. The membrane, with a thickness of 55 μm, showed a total flux of 308.4 g/m²h with a separation factor of 26.8 at 70 °C, and butanol permeability reached 11.13×10⁵ Barrer with a membrane selectivity of 56.0.     

Preparation and thermoelectric properties of SiO<Subscript>2</Subscript>/<Emphasis Type="Italic">β</Emphasis>-Zn<Subscript>4</Subscript>Sb<Subscript>3</Subscript> nanocomposite materials

A series of SiO₂/β-Zn₄Sb₃ core-shell composite particles with 3, 6, 9, and 12 nm of SiO₂ shell in thickness were prepared by coating β-Zn₄Sb₃ microparticles with SiO₂ nanoparticles formed by hydrolyzing the tetraethoxysilane in alcohol-alkali-water solution. SiO₂/β-Zn₄Sb₃ nanocomposite thermoelectric materials were fabricated with these core-shell composite particles by spark plasma sintering (SPS) method. Microstructure, phase composition, and thermoelectric properties of SiO₂/β-Zn₄Sb₃ nanocomposite thermoelectric materials were systemically investigated. The results show that β-Zn₄Sb₃ microparticles are uniformly coated by SiO₂ nanoparticles, and no any phase transformation reaction takes place during SPS process. The electrical and thermal conductivity gradually decreases, and the Seebeck coefficient increases compared to that of β-Zn₄Sb₃ bulk material, but the increment of Seebeck coefficient in high temperature range remarkably increases. The thermal conductivity of SiO₂/β-Zn₄Sb₃ nanocomposite material with 12 nm of SiO₂ shell is the lowest and only 0.56 W·m⁻¹·K⁻¹ at 460 K. As a result, the ZT value of the SiO₂/β-Zn₄Sb₃ nanocomposite material reaches 0.87 at 700 K and increases by 30%.     

Dendrite crystal morphology evolution mechanism of <Emphasis Type="Italic">β</Emphasis>-BaB<Subscript>2</Subscript>O<Subscript>4</Subscript> crystal

Existence of [B₃-O₆]³⁻ hexagonal ring growth unit in melt solution of β-BaB₂O₄ crystal was proved by the results of high temperature Raman measurements. A morphology evolution process of β-BaB₂O₄ crystal was observed by a high temperature in-situ observation device. The crystal morphology varied with the supersaturation of growth melt solution. The mechanism of β-BaB₂O₄ crystal morphology evolution was analyzed through the growth unit model. Supported by the National Natural Science Foundation of China (Grant No. 60808026) and the Nanjing University of Aeronautics and Astronautics Scientific Research Fund (Grant No. S0764-081)     

Effect of Nd<Subscript>2</Subscript>Fe<Subscript>14</Subscript>B/<Emphasis Type="Italic">α</Emphasis>-Fe nanocomposite permanent magnets with a combined Co and Nb additions

Influence of Co+Nb on the Nd₈Fe₈₂Co₃Nb₁B₆ nanocomposite magnets was investigated by adding Co element combined with Nb element. Results show that the high temperature stability of two phases is increased. Adding Co+Nb could improve the glass forming ability of the alloy, reduce the size of grains, increase the exchange coupling ability of two phases, and obviously increase the magnetic properties of the alloy. The optimal magnetic properties are B _r=1.14 T, H _cj=320 kA/m, (BH)max-109.3 kJ/m³.     

Elimination of Voids at Interface of <Emphasis Type="Italic">β</Emphasis>-SiC Films and Si Substrate by Laser CVD

Void-free β-SiC films were deposited on Si(001) substrates by laser chemical vapor deposition using hexamethyldisilane (HMDS) as the precursor. The effect of the time of introducing HMDS, i e, the substrate temperature when HMDS introduced (T_in), on the preferred orientation, surface microstructure and void was investigated. The orientation of the deposited SiC films changed from <001> to random to <111> with increasing T_in. The surface showed a layer-by-layer microstructure with voids above T_in ? 773 K, and then transformed into mosaic structure without voids at T_in= 298 K. The mechanism of the elimination of voids was discussed. At T_in =298 K, Si surface can be covered by an ultrathin SiC film, which inhibits the out-diffusion of Si atoms from substrate and prohibites the formation of the voids.     

Evaluation of a novel bioabsorbable PRGD/PDLLA/<Emphasis Type="Italic">β</Emphasis>-TCP/NGF composites in repair of peripheral nerves

Peripheral nerve regeneration using a novel nerve conduit (PRGD/PDLLA/β TCP/NGF) was evaluated, which was made of RGD peptide modified poly{(lactic acid)-co-[(glycolic acid)-alt-(L-lysine)]} (PRGD), poly(d,l-lactic acid) (PDLLA) and β-tricalcium phosphate (β-TCP). And the effectiveness was compared with that of PRGD/PDLLA/β-TCP, PDLLA and autograft in terms of nerve regeneration across a gap. Both of biodegradablity and cell-biocompatibility of the novel nerve conduit were evaluated in vitro. The results show that PRGD/PDLLA/β-TCP/NGF composite materials have better biodegradation properties and cell affinity than PDLLA, and could promote the RSC96 Schwann cells adhesion, proliferation and growth on the surface of materials. PRGD/PDLLA/β-TCP/NGF composite conduit was significantly superior to that of the PDLLA conduit in histological and axon morphologic index. PRGD/PDLLA/β-TCP/NGF conduit is more beneficial to nerve regeneration than PDLLA conduit. The biodegradable PDLLA/PRGD/β-TCP/NGF conduit has a good biocompatibility with rats tissue and it could effectively promote the nerve regeneration after bridging sciatic nerve defect of rats, the effect is as good as that of the autograft nerve, significantly superior to the PRGD/PDLLA/β-TCP conduit and PDLLA conduit. PDLLA/PRGD/β-TCP/NGF composite conduit is a potential ideal conduit. Funded by 973 State Key Fundamental Research and Development (No. G2005CB623905)