bluuebunny/crossref_metadata_2025_split huggingface dataset:
Etat et évolution de la ressource forestière feuillue en Suisse. Résultats du deuxième inventaire forestier national (IFN 2) | State and Development of Hardwood Resources in Swiss Forests – Results of the Second National Forest Inventory (NFI 2)
Authors: Brändli Urs-Beat 
Published: June 2007

The results of the second national forest inventory (NFI 2) allow a reliable and comprehensive assessment of the Swiss forests'development for the first time. One of the most obvious changes is the important increase in hardwoos. The most significant facts of NFI for hardwood-resources are presented as the basis for discussions and measures for an increased hardwood utilisation.
The whole stock in Swiss forests amounts to 418 Mio m3. About 60% of the hardwood stock of 118 Mio m3 is beech. The share of hardwood has increased by 2% both in surface and growing stock. These developments will remain constant in the future. The increase in stock amounts to 5% in softwood,whereas the one of hardwood amounts to 12%, maple and ash are dominating. The most important increase in standing volume is evident in trees of 36 to 52 cm DBH. With an unchanged utilisation, the share in large timber will further increase.
The increase was harvested to 80% in softwood, to 59% in hardwood, less so, however, in the French part than in the rest of Switzerland. But in the distinct cantons, not more than 40 to 80% of the increment of hardwood has been harvested. In hardwood, the non-exploited increment amounts to 1.4 Mio m3per year, of which 58% is beech, almost as the growing stock. For silvicultural reasons, it would be possible to double the volume of exploited hardwood – which would make sense, too,for ecological and socio-economic reasons. However, the calculated harvest expenditure for such an increased utilisation is in most of the cases high above the present average proceeds for hardwood.
111 années d'application de la méthode du contrôle à la forêt de Couvet | 111 years of application of the method of control in the community forest of Couvet
Authors: Favre Louis-André , Oberson Jean-Michel 
Published: June 2007

Starting in 1890 Henry Biolley progressively introduced the method of control in forests which came under his administration. The first forest to be managed according to the method of control was the community forest of Couvet in Canton Neuchatel and it can therefore be seen as the cradle of selection cutting. The experimental character of the method of control is precisely the incentive managers need to opt in favour of selection cutting.
The consistency in application and the introduction of technical methods over an extended period of time lend great weight to the data collected in 17 inventories. As all data regarding variations of stock, composition of classes and species, as well as current increment, are entirely comparable they can be analysed and aid the search for a balanced state. Selection cutting is essentially an ongoing process.
Die zukünftige Waldforschung an der WSL | The future of forest research at WSL
Authors: Broggi Mario F. , Oester Bernhard 
Published: June 2007

Forest research is going through a period of decisive change in terms of both structure and values as a result of economic and social developments. Researchers from the Department «Forest» at WSL have, therefore, been discussing potential challenges with other experts in order to be able to identify problems early and anticipate the consequences of global developments. We have been asking ourselves questions like: Are we doing the right thing? And are we doing it in the right way?
We have drawn on these discussions in setting our longterm goals and core research areas for the next few years. The Department «Forest» plans to continue to focus mainly on ecological research but also to consider topics more from the points of view of economics and direct implementation. Steps in this direction have already been taken. The WSL Programme«Future-oriented Management of Forest Use» has been launched and the Section «Economics» has been strengthened with more people employed. The Section «Silvicultural Strategies» focuses on studying long-term forest development. It then uses these research findings to work out effective silvicultural strategies to steer the development of the forest.
Thorough knowledge of the forest ecosystem and of the processes that take place within it is essential in order to answer the many questions raised. The Section «Forest Ecosystems and Ecological Risks» is investigating these processes and cause-effect relationships in forest ecosystems. It estimates the risks arising from changing environmental conditions. The Section«Soil Ecology» is concerned with long-term processes and changes taking place in the soil. It studies the influence of the increased deposition of acids, nitrogen compounds and inorganic pollutants, in particular heavy metals, on the soil and the associated risks to plants, soil-dwelling creatures and the groundwater.
The Section «Forest and Environmental Protection» has become known as the centre for expertise on forest health in Switzerland. It makes recommendations and disseminates research findings and data to do with current issues in forest conservation.
We are performing top research in these areas and are well known in international research circles, as the ETH-Council expects us to be. We intend in future to offer more support to those responsible for or interested in forests by providing applicable and future-oriented solutions to important and complex problems.
Ursachen und Verlauf der Buchdrucker-Epidemien (Ips typographus L.) in der Schweiz von 1984 bis 1999 | Causes and progress of the eight-toothed spruce bark beetle epidemics (Ips typographus) in Switzerland from 1984 to 1999
Authors: Meier Franz , Gall Rolf , Forster Beat 
Published: June 2007

In the past 20 years, several mass attacks by the eight-toothed spruce bark beetle (Ips typographus L.) occurred in Switzerland. Since 1984 data on compulsory fellings, numbers of infestation spots and numbers of beetles captured in pheromone traps have been collected in all Swiss forest districts. The annual data were published in short reports.
This paper gives an overview of the progress of bark beetle epidemics from 1984 to 1999. On the national level, two periods with epidemics of the spruce bark beetle can be distinguished. The first epidemic started after windthrows and drought in the years 1982 and 1983. It reached its height in 1984/1985 and faded at the end of the decade. The second epidemic started after the storm Vivian (February 1990). It reached its height in 1992/1993 and ended in 1997. Storm damage that produced high quantities of suitable breeding material was not the only factor for the bark beetle gradation;weather conditions were also exceptional, such as hot and dry vegetation periods.
Windthrows and exceptional weather conditions are mostly events on regional scales and do not affect the whole country with the same intensity. The gradation that appears to be an «epidemic of the spruce bark beetle in Switzerland after the storm Vivian» is in truth the accumulation of several local epidemics. This is shown by the number of compulsory fellings and infestation spots analysed at regional levels. Extreme weather conditions and storms not only directly influence the bark beetle population, they also stress standing trees, thus creating suitable breeding material for bark beetles. To analyse the influence of exceptional weather conditions on bark beetle epidemics,it is therefore necessary to evaluate regional data.
Le pinson du Nord Fringilla montifringilla L.: un visiteur d'exception dans les forêts d'Ajoie durant l'hiver 2001–2002 | The brambling Fringilla montifringilla L.: a rare visitor in the forests of Ajoie in winter 2001/2002
Authors: Chalverat Joseph 
Published: June 2007

In the winter of 2001/2002, over a period lasting 110 days, ten to twelve million bramblings (northern Eurasian finches)sought a place to sleep in the region of Villars-sur-Fontenais in Canton Jura, Switzerland. Suitable resting places in the proximity of access roads enabled a great number of ornithologists to carry out regular and numerous observations that were collected by the author in Jura's Natural Science Museum in Porrentruy. A lot of new information on the behaviour of the bramblings at their places of rest was collected, both during the day, on their return, and was also closely observed and described with regard to weather conditions and the change of season. Information was also collected on the ethology of predators.
The special aspect of the article is the visit to the resting places after the departure of the bramblings. Much new knowledge was gained from this. Pseudombrophila stercofringilla,a newly discovered Ascomyzete, was actually found by its discoverer in situ. The effect was detected of uric acid,which turned the ground plants brown and destroyed fir needles from the previous year. It would be a worthwhile subject of scientific inquiry to study the effect of enrichment with fertiliser – manifest on trees and mushrooms. A regional study would make it possible to examine whether the scratching activity of the bramblings, allowing beechnuts to fall on fruitful ground, have a positive effect of regeneration of beech forests in the long term.
Field Emission SEM Studies on Softwood Tracheids and Hardwood Fibres – A Review of Activities at the EMPA Wood Laboratory
Authors: Zimmermann Tanja , Sell Jürgen 
Published: June 2007

Over the past ten years transverse fracture surfaces of tensionloaded softwoods, hardwoods and reaction wood have been studied using a high resolution FE SEM. Due to the fracture process the cell wall becomes loosened and its components can be distinctly observed (as opposed to smooth cross sections of cut wood). Softwood tracheids (compression wood, too) and hardwood fibres showed predominantly radial orientations(perpendicular to the other layers) of the cellulosic fibrils of the secondary wall layer 2 (S2). Similar structures were found on sections of different hardwoods degraded by white rot fungi. Contrary to that finding there is no discernible preferential orientation of the cellulose fibrils in the S2 or G layer of pronounced tension wood cells.
In our opinion functional advantages of such structures in the strengthening tissue are quite clear. The sandwich-like structure is important for the buckling resistance of the tracheids and fibre cell walls and therefore also to the bending stiffness of the whole tree. Tension wood fibres of hardwood trees solely exposed to longitudinal tension do probably not need a compression stiffening, explaining why transverse fibril agglomerations are absent here. In many other studies a polylaminated concentric arrangement of the cellulose/ ligninhemicellulose matrix in the S2 layer is postulated and clearly documented.
Taking our results into account, we conclude that concentric and/or radial arrangements (perpendicular to the CML) in the S2 of softwood tracheids and hardwood fibres coexist for good ontogenetic, physiological, and mechanical reasons.
Qualitative and Quantitative Analysis of Plastics, Polymers and Rubbers by Vibrational Spectroscopy
Authors: Chalmers John M. , Everall Neil J. 
Published: June 2007

Abstract
The vibrational spectroscopy techniques of infrared spectroscopy and Raman spectroscopy are widely used for the analysis and characterization of organic polymers, plastics and rubbers, and their products. They are used to both identify and to probe the molecular microstructure and morphology of polymers and articles fabricated from them, and to investigate and monitor their synthesis and manufacture.
This chapter begins with a short discussion on the range of sample forms and properties that are amenable to study using vibrational spectroscopy. This is followed by concise descriptions of sampling techniques as they apply to polymer analysis. Discussions of qualitative and quantitative analysis and the peculiarities associated with polymer infrared and Raman spectra are then followed by more specific applications sections, which cover: dichroism and molecular orientation; end groups and branching; hydrogen bonding; blends and miscibility studies; copolymer composition; polymerisation and cure studies; degradation and oxidation; chromatography, pyrolysis, evolved gas analysis and thermogravimetric analysis coupled with vibrational spectroscopy; optical properties and constants; two‐dimensional vibrational spectroscopy; process measurements; and, infrared and Raman microspectroscopy.
This chapter is a prelude to the more specific and specialized chapters that follow in this book.
Vibrational Spectroscopic Analysis for the Determination of
S
tructure–
A
ctivity
R
elationships (
SARs
) in Molecular Binding
Authors: Pivonka Don E. , Noda Isao 
Published: June 2007

Abstract
This chapter details an application of vibrational spectroscopy that has been developed as a tool for understanding how both the physical structure and the electronic properties of a molecule are related to activity within a biological assay, i.e., the structure‐activity relationship (SAR). In that context, vibrational spectroscopy has first been developed as a tool for identification of the molecular subcomponents within a compound series that play an active role in binding kinetics. Second, vibrational spectroscopy has exhibited utility in uncovering electronic trends within both pendant functional groups and within the molecular backbone scaffold that foster the binding process.
In this chapter, several series of compounds, within a human estrogen receptor (β‐ER) study, are used to illustrate the feasibility of the technique. In each series, infrared and Raman band shifts that correlated with β‐ER activity, were identified. Also in each series, the electronic state of the fused ring scaffold system was found to play a critical role in binding. The ability to relate the physical/electronic state of a molecular subcomponent to activity has far reaching implications in the identification and optimization of binding activity. The preliminary success of this project opens the door to a much broader investigation of the technique using a host of spectroscopic methodologies.
Fabrication of Au/PVP nanofiber composites by electrospinning
Authors: Wang Yongzhi , Li Yaoxian , Sun Guoen , Zhang Guangliang , Liu Hui , Du Jianshi , Yang Songtao , Bai Jie , Yang Qingbiao 
Published: June 2007

AbstractGold nanoparticles prepared by trisodium citrate reduction of HAuCl4 in poly(vinylpyrrolidone) (PVP) ethanol solution were dispersed into PVP nanofibers by electrospinning. The optical property of Au nanoparticles before and after electrospinning was measured by UV‐Vis. The morphology and distribution of gold nanoparticles in PVP nanofibers were observed by transmission electron microscopy (TEM). The influence of the amount of Au added to and the concentration of PVP in electrospinning solution over the morphology of Au/PVP nanofibers were studied. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007
Some factors influencing exfoliation and physical property enhancement in nanoclay epoxy resins based on diglycidyl ethers of bisphenol A and F
Authors: Ingram S. , Rhoney I. , Liggat J. J. , Hudson N. E. , Pethrick R. A. 
Published: June 2007

AbstractAn investigation of the factors influencing the degree of exfoliation of an organically modified clay in a series of epoxy resins is reported. The use of sonication, choice of curing agent, effect of the moisture content of the clay, and the cure temperature were examined. The dispersion was characterized using a combination of rheological measurements, X‐ray diffraction, and dynamic mechanical thermal analysis. Rheological analysis of the clay dispersion in the epoxy monomer indicated that at high clay loads Herschel–Bulkley type behavior is followed. Higher cure temperatures and higher levels of clay moisture were found to influence the extent of exfoliation. Improvements in physical properties were observed through the addition of nanocomposites. The DGEBA/DDM and DEGEBA/DDS exhibited 2 and 4°C increase, respectively, in Tg per wt % of added clay. DGEBF showed virtually no enhancement. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007
Effect of end group content on photochromic behavior of spiropyran in polycaprolactone–poly(ethylene succinate) blends
Authors: Samoladas A. , Jannakoudakis A. , Bikiaris D. , Chrissafis K. , Paraskevopoulos K. M. 
Published: June 2007

AbstractThe photochromic behavior of the spiropyran 1′,3′‐dihydro‐8‐methoxy‐1′,3′,3′‐trimethyl‐6‐nitrospiro[2H‐1‐benzopyran‐2,2′‐(2H)‐indole] has been investigated in thin films of polycaprolactone–poly(ethylene succinate) blends containing different weight ratios of poly(ethylene succinate) (PESu) and spiropyran. The effects of molecular weight and end group content (COOH and OH) of PESu into the coloration–decoloration rate of the fabricated photochromic films have also been examined. The films were exposed to UV radiation (365 nm) at ambient temperature and the absorbance spectra of each polymer blend film were recorded for different time periods. The increase of the amount of PESu in the polymer substrate from 20 to 40 wt % shifts the absorbance towards shorter wavelengths. The same trend was also observed with the increase of carboxyl and hydroxyl groups of the macromolecular chain of the added PESu. Interactions between the polar polymer groups and the spiropyran species, which are formed under the UV excitation, seem to contribute to the color stabilization of the photochromic films. The photochromic response revealed unexceptional repeatability between the slightly colored spiropyran and the intense colored amphoteric species for all the examined polymer matrices. The decoloration rate of the spiropyran–polymer blends follow the kinetic of a first order reaction. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007
Polymerization of acrylonitrile using potassium peroxydisulfate as an initiator in the presence of a multisite phase‐transfer catalyst: A kinetic study
Authors: Vajjiravel Murugesan , Umapathy M. J. , Bharathbabu M. 
Published: June 2007

AbstractIn this article, the kinetics and mechanism of the free‐radical polymerization of acrylonitrile (AN) using potassium peroxydisulfate (PDS) as a water‐soluble initiator in the presence of synthesized 1,4‐bis(triethyl methyl ammonium) benzene dichloride (DC‐X) as a phase‐transfer catalyst (PTC) were studied. The polymerization reactions were carried out under inert and unstirred conditions at a constant temperature of 60 ± 1°C in cyclohexane/water biphasic media. The rate of polymerization (Rp) increased with an increase in the concentrations of AN, PTC, and PDS. The order with respect to the monomer, initiator, and PTC was found to be 1.0, 0.5, and 0.5, respectively. Rp was independent of the ionic strength and pH of the medium. However, an increase in the polarity of the solvent slightly increased the Rp value. On the basis of the obtained results, a mechanism is proposed for the polymerization reaction. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007
Pervaporation characteristics and structure of poly(vinyl alcohol)/poly(ethylene glycol)/tetraethoxysilane hybrid membranes
Authors: Ye Li Yi , Liu Qing Lin , Zhang Qiu Gen , Zhu Ai Mei , Zhou Guo Bo 
Published: June 2007

AbstractPoly(vinyl alcohol) (PVA) blended with poly(ethylene glycol) (PEG) was crosslinked with tetraethoxysilane (TEOS) to prepare organic–inorganic PVA/PEG/TEOS hybrid membranes. The membranes were then used for the dehydration of ethanol by pervaporation (PV). The physicochemical structure of the hybrid membranes was studied with Fourier transform infrared spectra (FT‐IR), wide‐angle X‐ray diffraction WXRD, and scanning electron microscopy (SEM). PVA and PEG were crosslinked with TEOS, and the crosslinking density increased with increases in the TEOS content, annealing temperature, and time. The water permselectivity of the hybrid membranes increased with increasing annealing temperature or time; however, the permeation fluxes decreased at the same time. SEM pictures showed that phase separation took place in the hybrid membranes when the TEOS content was greater than 15 wt %. The water permselectivity increased with the addition of TEOS and reached the maximum at 10 wt % TEOS. The water permselectivity decreased, whereas the permeation flux increased, with an increase in the feed water content or feed temperature. The hybrid membrane that was annealed at 130°C for 12 h exhibited high permselectivity with a separation factor of 300 and a permeation flux of 0.046 kg m−2 h−1 in PV of 15 wt % water in ethanol. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007
Novel high‐dielectric‐permittivity poly(vinylidene fluoride)/polypropylene blend composites: The influence of the poly(vinylidene fluoride) concentration and compatibilizer
Authors: Dang Zhi‐Min , Yan Wei‐Tao , Xu Hai‐Ping 
Published: June 2007

AbstractNovel high‐dielectric‐permittivity poly(vinylidene fluoride) (PVDF)/polypropylene (PP) blend composites were prepared via a blending technology, and their dielectric properties were studied over wide ranges of temperatures and frequencies. To improve the interface bonding between PVDF and PP, a suitable compatibilizer, polypropylene‐graft‐maleic anhydride (PP‐g‐MAH), was employed. The results showed that the concentration of PVDF in the composites dominated the changes in the dielectric properties and that the use of PP‐g‐MAH could improve the interface interaction between PVDF and PP, resulting in an increase in the dielectric permittivity. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007
pH‐sensitive swelling and release behaviors of anionic hydrogels for intelligent drug delivery system
Authors: Kim Bumsang , Shin Youngchan 
Published: June 2007

AbstractThe pH‐sensitive swelling and release behaviors of the anionic P(MAA‐co‐EGMA) hydrogels were investigated as a biological on–off switch for the design of an intelligent drug delivery system triggered by external pH changes. There was a drastic change of the equilibrium weight swelling ratio of P(MAA‐co‐EGMA) hydrogels at a pH of around 5, which is the pKa of poly (methacrylic acid) (PMAA). At a pH below 5, the hydrogels were in a relatively collapsed state but at a pH higher than 5, the hydrogels swelled to a high degree. When the molecular weight of the pendent poly(ethylene glycol) (PEG) of the P(MAA‐co‐EGMA) increased, the swelling ratio decreased at a pH higher than 5. The pKa values of the P(MAA‐co‐EGMA) hydrogels moved to a higher pH range as the pendent PEG molecular weight increased. When the feed concentration of the crosslinker of the hydrogel increased the swelling ratio of the P(MAA‐co‐EGMA) hydrogels decreased at a pH higher than 5. In release experiments using Rhodamine B (Rh‐B) as a model solute, the P(MAA‐co‐EGMA) hydrogels showed a pH‐sensitive release behavior. At low pH (pH 4.0) a small amount of Rh‐B was released while at high pH (pH 6.0) a relatively large amount of Rh‐B was released from the hydrogels. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007