A novel germanium/carbon nanotubes nanocomposite for lithium storage material

A new nanocomposite of Ge/carbon nanotubes (n-Ge/CNTs) was reported by a facile precursor method through a pyrolysis technique. Among it, germanium nanoparticles are encapsulated with a thin layer of amorphous carbon, which benefits to keep a good electronic contact with carbon nanotubes. Germanium nanoparticles are mainly supported inside the carbon nanotubes, which can effectively buffer the volume changes of Germanium. The composite was an effectively mixed (Li⁺ and e⁻) conducting network, which is vital to a quick Li insertion. The composite was shown to exhibit a reversible capacity of about 750 mAh g⁻¹ (74.4 mA g⁻¹) and an improved rate performance, compared with that of CNTs processed as the same condition. Our results demonstrated the composite to be a good active Li-storage material for Li batteries.     

Long‐term testing of a high temperature polymer electrolyte membrane fuel cell: The effect of reactant gases

The investigations have been conducted with different oxidants and fuels with the aim of determining the state‐of‐the‐art of commercially available high temperature polymer electrolyte fuel cells based on polybenzimidazole for its application in combined heat and power generation systems. The fuel cell test performed with synthetic reformate (?63 μV/h) showed an increase of anode charge and mass transfer resistances. This behavior has suggested that CO may be generated from the CO₂ included in the synthetic reformate via reverse water gas shift reaction. The fuel cell test performed with pure O₂ developed the highest degradation rates (?70 μV/h) due to fast oxidative degradation of membrane electrode assembly materials such as cathode catalyst and membrane. Fuel cell operation with H₂/air exhibited the lowest degradation rates (?57 μV/h) and it requires longer investigating times to identify the different degradation mechanisms. Moreover, fuel cell tests performed with air suggested longer break‐in procedures to complete catalyst activation and redistribution of electrolyte. © 2015 American Institute of Chemical Engineers AIChE J, 62: 217–227, 2016     

Ketone bodies,glucose and glutamine as lipogenic precursors in human diploid fibroblasts

Incorporation of [¹⁴C] from acetoacetate, D(-)- and L(+)-3-hydroxybutyrate, glucose, glutamine, acetate and palmitate in cellular lipids were studied in cultures in human diploid fibroblasts (HDF). The results showed that acetoacetate was 2–10 times more effective as a lipogenic precursor than was either D- or L-3-hydroxybutyrate. Its extent of incorporation into lipids was 2- to 8-fold more than the other precursors examined under conditions when the overall rates of nonsaponifiable and saponi-fiable lipogenesis as measured by³H₂O incorporation were essentially unchanged. Acetoacetate supported both saponifiable and nonsaponifiable lipid syntheses with half-saturation values (K_m app.) of 185 μM and 30 μM, respectively. Glucose stimulated acetoacetate incorporation into lipids whereas, conversely, acetoacetate inhibited [¹⁴C] glucose incorporation into lipids. The presence of low density lipoproteins (LDL) cholesterol (@40 μg cholesterol/mL) inhibited the incorporation of [¹⁴C] from acetoacetate 56% into nonsaponifiable lipids; the inhibition was consistently higher (75%) when [¹⁴C] glucose or glutamine were the precrusors. The loss of 3-hydroxy-3-methyl-glutaryl CoA (HMG CoA) reductase activity upon addition of LDL-cholesterol was greater than the suppression of [¹⁴C] incorporation from acetoacetate or glucose into nonsaponifiable lipids. In the presence of glucose, [¹⁴C] acetoacetate was incorporated into 3-βOH sterols (digitonin precipitable). 7.7±1.1 times more effectively than was [¹⁴C] glucose. The results suggest that HDF would be a suitable model to investigate the effects of various precrusors of HMG CoA on the rate of cholesterol biosynthesis.     

Investigation of the performance of carbide cutting tools with hard coatings in hard milling based on the response surface methodology

Machining of hard materials has become a great challenge for several decades. One of the problems in this machining process is early tool wear, and this affects the machinability of hard materials. In order to increase machinability, cutting tools are widely coated with nanostructured physical vapor deposition hard coatings. The main characteristics of such advanced hard coatings are high microhardness and toughness as well as good adhesion to the substrate. In this paper, the influence of hard coatings (nanolayer AlTiN/TiN, multilayer nanocomposite TiAlSiN/TiSiN/TiAlN, and commercially available TiN/TiAlN) and cutting parameters (cutting speed, feed rate, and depth of cut) on cutting forces and surface roughness were investigated during face milling of AISI O2 cold work tool steel (～61 HRC). The experiments were conducted based on 3¹³ factorial design by response surface methodology, and response surface equations of cutting forces and surface roughness were obtained. In addition, the cutting forces obtained with the coated and uncoated tools were compared. The results showed that the interaction of coating type and depth of cut affects surface roughness. The hard coating type has no significant effect on cutting forces, while the cutting force F _z is approximately two times higher in the case of uncoated tool.     

Spatial planning for landscape: mapping the pitfalls

While welcoming the European Landscape Convention and acknowledging the successes of conservation organizations such as the National Trust in Britain, the Czech Village Restoration Scheme and the French eco‐musées, this paper identifies some of the pitfalls that must be avoided if the fine words of the Convention are to be translated into effective action. These include problems with designation, conflicts between different types of conservation, and the side effects of gentrification and increased tourism. There is a call for more research to break down barriers to understanding between countries, between disciplines, and between academics and practitioners.     

The Role of Farm Advisors in Multifunctional Landscapes: A Comparative Study of Three Danish Areas, 1995 and 2008

This study investigates the influence of farm advisors on farmers’ decisions regarding ‘Multifunctional landscape commons’, a concept covering environmental and landscape values that benefit the public but which depend on farmers’ management practices. The influence of advisors is analysed by combining data about the source of advice with evidence of land use and landscape changes and participation in subsidy schemes. The study compares three agricultural areas in Denmark. Structured interviews were carried out with all farmers possessing more than 2 ha land in 1995–6 and in 2008. Vertical, production and business-oriented advisory services predominate, together with legal and organisational spatial competence networks. A new group of hobby farmers and pensioned farmers tend not to be included in traditional advisory networks, leaving them to carry out landscape changes and multifunctional landscape commons without professional guidance and consultancy. This means the horizontal coordination among farmers, that is, the territorial competences, decrease.     

Assessing filter robustness at drinking water treatment plants

This investigation explores the use of five‐parameter logistic curve fitting in quantifying turbidity robustness and risk scoring in clarification and filtrations stages of several surface water treatment works in the Anglian Water region of the United Kingdom. The approach taken reviews different scoring systems and addresses issues of weighting, averages and variability in robustness performance using turbidity robustness indices (TRIs). It also proposes an area‐based risk scoring profile to assess performance [relative area profile for T₉₀ (RAP₉₀)]. The metrics produced are considered to be a logical and rational way to help prioritise where resources for water treatment operation should be deployed.