bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparative investigation on crystallization conditions dependence of polymorphs composition for β‐nucleated propylene/ethylene copolymer and propylene homopolymer
Authors: Xiao Wenchang , Feng Jiachun
Published: May 2010

The crystallization conditions dependence of polymorphs composition in β nucleated propylene/ethylene copolymers (PPR) and propylene homopolymers (PPH) were comparatively investigated via wide angle X‐ray diffraction (WAXD) and differential scanning calorimetry (DSC) measurements. It is interesting to note that the amount of β form as a function of crystallization conditions presents an opposite trend for the β nucleated PPR and the β nucleated PPH under the conditions we investigated. For the β nucleated copolymers, the content of β form shows also an opposite tendency with that of γ form with the change of crystallization conditions. The formation of γ form is preferred under lower cooling rates or higher isothermal crystallization temperatures, whereas the amount of β form increased with increasing the cooling rates or decreasing the isothermal temperatures. This opposite tendency could be interpreted in terms of the competition between the β nucleation ability of β nucleating agent and the γ nucleation action of the comonomer defects. The existing comonomer defects that favor the formation of γ form may suppress the nucleation ability of β nucleating agent. A higher proportion of β form in PPR containing a β nucleating agent could be achieved under faster cooling rates or lower crystallization temperatures. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Cross‐linked agarose for separation of low molecular weight natural products in hydrophilic interaction liquid chromatography
Authors: Tan Tianwei , Su Zhi‐Guo , Gu Ming , Xu Jun , Janson Jan‐Christer
Published: May 2010

Following its market introduction in 1982, the cross‐linked 12% agarose gel media Superose 12 has become widely known as a tool for size exclusion chromatography of proteins and other biological macromolecules. In this review it is shown that, when appropriate mobile phases are used, Superose possesses adsorption properties similar to that of traditional media for hydrophilic interaction liquid chromatography (HILIC). This is illustrated by the separation and purification of low molecular weight compounds such as polyphenols including active components of traditional Chinese medicinal herbs and green tea. Structural features of the cross‐linked agarose that likely cause the observed adsorption effects are discussed aswell. These are identified as being primarily ether bonds acting as strong hydrogen bond acceptors as well as hydrophobic residues originating from the cross‐linking reagents.
Development of a validated LC method for enantiomeric separation and determination of adrafinil and its related substances on a Chiralcel OJ‐H column connected to PDA and polarimetric detectors in series
Authors: Rao R. Nageswara , Maurya Pawan K. , Shinde Dhananjay D.
Published: May 2010

A rapid and reliable high‐performance liquid chromatographic method for resolution of enantiomers of adrafinil [(±)‐ADL], a novel vigilance promoting agent, and its synthetic intermediates was developed. The separation was carried out on a Chiralcel OJ‐H using n‐hexane–ethanol (62:38 v/v) as a mobile phase. The detection was carried out at 225 nm using a photodiode array (PDA) detector. The optical rotation and order of elution of enantiomers were assigned. The method is suitable not only for process development of ADL but also for quality assurance of bulk drugs and pharmaceuticals. Copyright © 2010 John Wiley & Sons, Ltd.
A rapid and reliable UPLC‐MS/MS method for the identification and quantification of fourteen synthetic anti‐diabetic drugs in adulterated Chinese proprietary medicines and dietary supplements
Authors: Li Ning , Cui Mei , Lu Xiumei , Qin Feng , Jiang Kun , Li Famei
Published: May 2010

An ultraperformance liquid chromatography–tandem mass spectrometry (UPLC‐MS/MS) method was developed for simultaneous qualitative and quantitative analysis of 14 synthetic anti‐diabetic drugs in adulterated Chinese proprietary medicines (CPMs) and dietary supplements. The samples were prepared by ultrasonic extraction with methanol and separated on a C18 column with mobile phase consisting of acetonitrile and water (both containing 0.10% formic acid). Gradient elution was applied with a flow rate of 0.20 mL/min. Two transitions from protonated molecules were monitored for each synthetic anti‐diabetic drug in positive mode of electrospray ionization (ESI). The two transitions, the peak area ratio of the two transitions and the retention time were used for identification. The more intensive transition was used for quantification. The analysis time was 6 min per sample. Satisfactory linear relationships were estimated between the peak area and the concentration with correlation coefficients higher than 0.995. The limit of detection ranged from 0.03 to 5.45 ng/mL. The relative standard deviation of intra‐day precision was below 7.6%, the RSD of inter‐day precision was below 15% and the relative error of accuracy was between –10 and 7.8%. The proposed method is rapid, selective, reliable and was successfully applied to the analysis of 30 real samples of 22 CPMs and eight dietary supplements from the local market in China. Copyright © 2010 John Wiley & Sons, Ltd.
Sustainable procurement practice
Authors: Meehan Joanne , Bryde David
Published: May 2010

Procurement has a key role in sustainability as policies and practices need to extend beyond organisations' boundaries incorporating their whole supply chains. Guidelines on sustainability encourage procurement to make decisions that encompass the environmental, economic and social elements of the Triple Bottom Line (TBL). Taking a supply chain perspective, procurement also need to analyse how decisions impact on the TBL in respect of suppliers. The results of a survey of sustainable procurement practices in 44 English‐based UK Housing Associations (HAs), who are responsible for the provision of social housing, confirms prior research of other sectors that suggests 1) a failure to overcome inertia in relation to sustainable procurement; and 2) in the few examples where practices have been established, only the environmental element of the TBL is considered. The organisations surveyed have sustainability‐related issues in their missions and external and internal pressures to embed sustainability, yet this has not translated into widespread establishment of sustainable procurement. Recommendations to neutralise inertia are: firstly, take the experiences from other areas, e.g. innovation management, which stress the importance of inter‐organisational relationships; secondly, develop a small number of sustainable development indicators for procurement and, to take advantage of the relatively more‐advanced environmental practices to show how these elements have socio‐economic impacts; and finally, rather than focus on just the pressures and drivers of sustainability (as suggested in strategic models of sustainability), emphasise the triggers that overcome inertia and lead to changes in behaviour amongst procurement staff i.e. the establishment of ethical pricing models. Copyright © 2010 John Wiley & Sons, Ltd and ERP Environment.
Electrochemical Syntheses of Cyclo[n]pyrrole
Authors: Buda Mihai , Iordache Adriana , Bucher Christophe , Moutet Jean‐Claude , Royal Guy , Saint‐Aman Eric , Sessler Jonathan L.
Published: May 2010

Cyclo[8]pyrrole was obtained efficiently when 3,3′,4,4′‐tetraethylbipyrrole was subjected to bulk electrolysis, with yields spanning a range from close to 0 % with tetra‐n‐butylammonium fluoride as the electrolyte, to almost 70 % when tetra‐n‐butylammonium hydrogensulfate was used for this purpose. These observations are consistent with the conclusion that the reaction is controlled by anion‐related factors such as a specific templating effect. Note that cyclo[8]pyrrole was the only detectable macrocyclic product obtained from 3,3′,4,4′‐tetraethylbipyrrole under the conditions of the electrochemical oxidation. When similar electrolyses were performed by using 3,4‐diethylpyrrole as the starting material, two products could be isolated, which were identified as being the cyclo[7]pyrrole and cyclo[8]pyrrole, respectively. Detailed analyses of the oxidized forms of cyclo[7]pyrrole and cyclo[8]pyrrole revealed that under the conditions of the electrolysis these latter species are not stable.
The A2Aadenosine receptor rescues neuritogenesis impaired by p53 blockage via KIF2A, a kinesin family member
Authors: Sun Chung‐Nan , Chuang Hsiu‐Chun , Wang Jiz‐Yuh , Chen Si‐Ying , Cheng Ya‐Yun , Lee Chien‐Fei , Chern Yijuang
Published: May 2010

The A2Aadenosine receptor (A2AR) is a G‐protein–coupled receptor. We previously reported that the C terminus of the A2AR binds to translin‐associated protein X (TRAX) and modulates nerve growth factor (NGF)‐evoked neurite outgrowth in PC12 cells. Herein, we show that neuritogenesis of primary hippocampal neurons requires p53 because blockage of p53 suppressed neurite outgrowth. The impaired neuritogenesis caused by p53 blockage was rescued by activation of the A2AR (designated the A2Arescue effect) in a TRAX‐dependent manner. Importantly, suppression of a TRAX‐interacting protein (kinesin heavy chain member 2A, KIF2A) inhibited the A2Arescue effect, whereas overexpression of KIF2A caused a rescue effect. Expression of a KIF2A fragment (KIF2A514), which disturbed the interaction between KIF2A and TRAX, blocked the rescue effect. Transient colocalization of TRAX and KIF2A was detected in the nucleus of PC12 cells upon NGF treatment. These data suggest that functional interaction between KIF2A and TRAX is critical for the A2Arescue effect. Moreover, p53 blockage during NGF treatment prevented the redistribution of KIF2A from the nucleus to the cytoplasmic region. Expression of a nuclear‐retained KIF2A variant (NLS‐KIF2A) did not rescue the impaired neurite outgrowth as did the wild‐type KIF2A. Therefore, redistribution of KIF2A to the cytoplasmic fraction is a prerequisite for neurite outgrowth. Collectively, we demonstrate that KIF2A functions downstream of p53 to mediate neuritogenesis of primary hippocampal neurons and PC12 cells. Stimulation of the A2AR rescued neuritogenesis impaired by p53 blockage via an interaction between TRAX and KIF2A. © 2010 Wiley Periodicals, Inc. Develop Neurobiol 70: 604–621, 2010
The Effect of Surface Area and Crystal Structure on the Catalytic Efficiency of Iron(III) Oxide Nanoparticles in Hydrogen Peroxide Decomposition
Authors: Gregor Cenek , Hermanek Martin , Jancik Dalibor , Pechousek Jiri , Filip Jan , Hrbac Jan , Zboril Radek
Published: May 2010

Iron(II) oxalate dihydrate has been used as a readily decomposable substance for the controlled synthesis of nanosized iron(III) oxides. The polymorphous composition, particle size and surface area of these iron oxide nanoparticles were controlled by varying the reaction temperature between 185 and 500 °C. As‐prepared samples were characterized by XRD, low‐temperature and in‐field Mössbauer spectroscopy, BET surface area and the TEM technique. They were also tested as heterogeneous catalysts in hydrogen peroxide decomposition. At the selected temperatures, the formed nanomaterials did not contain any traces of amorphous phase, which is known to considerably reduce the catalytic efficiency of iron(III) oxide catalysts. As the thickness of the sample (≈ 2 mm) was above the critical value, a temporary temperature increase (“exo effect”) was observed during all quasi‐isothermal decompositions studied, irrespective of the reaction temperature. Increasing the reaction temperature resulted in a shift of the exo effect towards shorter times and an increased content of maghemite phase. The maghemite content decreases above 350 °C as a result of a thermally induced polymorphous transition into hematite. The catalytic data demonstrate that the crystal structure of iron(III) oxide (i.e. the relative contents of maghemite and hematite) does not influence the rate of hydrogen peroxide decomposition. However, the rate constant increases monotonously with increasing sample surface area (and decreasing thermolysis temperature), reaching a maximum of 27 × 10–3 min–1(g/L)–1 for the sample with a surface area of 285 m2 g–1. This rate constant is currently the highest reported value of all known iron oxide catalytic systems and is even slightly higher than that observed for the most efficient catalyst reported to date, which has a significantly larger surface area of 337 m2 g–1. This surprisingly high catalytic activity at relatively low surface area can be ascribed to the absence of a amorphous phase in the samples prepared in this study. Taking into account these new findings, the contributions of the key factors highlighted above (surface area, particle size, crystal structure, crystallinity) to the overall activity of iron oxides forhydrogen peroxide decomposition are discussed.
Molybdenum Complexes Bearing the Tris(1‐pyrazolyl)methanesulfonate Ligand: Synthesis, Characterization and Electrochemical Behaviour
Authors: Dinoi Chiara , Guedes da Silva M. Fátima C. , Alegria Elisabete C. B. A. , Smoleński Piotr , Martins Luísa M. D. R. S. , Poli Rinaldo , Pombeiro Armando J. L.
Published: May 2010

The tris(1‐pyrazolyl)methanesulfonate lithium salt Li(Tpms) [Tpms = SO3C(pz)3–] reacts with [Mo(CO)6] in NCMe heated at reflux to yield Li[Mo(Tpms)(CO)3] (1), which, upon crystallization from thf, forms the coordination polymer [Mo(Tpms)(CO)2(μ‐CO)Li(thf)2]n (2). Reaction of 1 with I2, HBF4 or AgBF4 yields [Mo(Tpms)I(CO)3] (3), [Mo(Tpms)H(CO)3] (5) or [Mo(Tpms)O2]2(μ‐O) (7), respectively. The high‐oxidation‐state dinuclear complexes [{Mo(Tpms)O(μ‐O)}2] (4) and [{Mo(tpms)OCl}2](μ‐O) (6) are formed upon exposure to air of solutions of 3 and 5, respectively. Compounds 1–7, which appear to be the first tris(pyrazolyl)methanesulfonate complexes of molybdenum to be reported, were characterized by IR, 1H and 13C NMR spectroscopy, ESI‐MS, elemental analysis, cyclic voltammetry and, in the cases of Li(Tpms) and compounds 2, 4·2CH3CN, 6·6CHCl3 and 7, by X‐ray diffraction analyses. Li(Tpms) forms a 1D polymeric structure {i.e., [Li(tpms)]n} with Tpms as a tetradentate N2O2 chelating ligand that bridges two Li cations with distorted tetrahedral coordination. Compound 2 is a 1D coordination polymer in which Tpms acts as a bridging tetradentate N3O ligand and each Li(thf)2+ moiety is coordinated by one bridging CO ligand and by the sulfonyl group of a contiguous monomeric unit. In 4, 6 and 7, the Tpms ligand is a tridentate chelator either in the NNO (in 4) or in the NNN (in 6 and 7) fashion. Complexes 1, 3 and 5 exhibit, by cyclic voltammetry, a single‐electron oxidation at oxidation potential values that indicate that the Tpms ligand has an electron‐donor character weaker than that of cyclopentadienyl.
1,3,5‐Triazapentadiene Nickel(II) Complexes Derived from a Ketoxime‐Mediated Single‐Pot Transformation of Nitriles
Authors: Kopylovich Maximilian N. , Kirillov Alexander M. , Tronova Ekaterina A. , Haukka Matti , Kukushkin Vadim Yu. , Pombeiro Armando J. L.
Published: May 2010

A series of cationic (2+) [Ni{HN=C(R)NHC(R)=NH}2](X)2 {R = 4‐(Cl)C6H4 (1), 3‐(NC)C6H4 (3), 4‐(NC)C6H4 (4) and Me (7); X = Cl– (1, 3, 4) or MeCOO–·H2O (7)} and neutral [Ni{HN=C(R)NC(R)=NH}2](solvate) {R = 3‐(Cl)‐4‐py (2), 3‐py (5) and 4‐py (6); solvate = MeOH and/or H2O; py = pyridyl} N,N‐chelating bis(1,3,5‐triazapentadiene/ato)nickel(II) [Ni(tap)2]2+/0 complexes has been easily generated by a ketoxime‐mediated single‐pot reaction of a nickel(II) salt [NiCl2·2H2O or Ni(MeCOO)2·4H2O] with 4‐chlorobenzonitrile, isophthalonitrile, terephthalonitrile, acetonitrile, 2‐chloro‐4‐cyanopyridine, 3‐cyanopyridine or 4‐cyanopyridine, respectively. The obtained compounds have been characterized by IR, 1H and 13C{1H} NMR spectroscopy, FAB‐MS(+) or ESI‐MS(+), elemental analyses and single‐crystal X‐ray diffraction [for 7 and solvated mono‐ {1a·(Me2CO)0.33·(MeOH)0.67} and bis‐deprotonated (2b·2Me2CO, 4b·CHCl3, 5b·Me2CO and 6b·MeOH) products, formed upon recrystallization of 1, 2, 4, 5 and 6, respectively]. The crystal structures of all compounds bear similar monomeric Ni(tap)2 units with a nearly square‐planar geometry. In addition, the structure of 7 features the formation of infinite 1D zig‐zag water–acetate chains {[(H2O)2(MeCOO)2]2–}n, which multiply interact with the [Ni(tap)2]2+ cations to generate a 2D hydrogen‐bonded supramolecular assembly.
Differentiable cortical networks for inferences concerning people's intentions versus physical causality
Authors: Mason Robert A. , Just Marcel Adam
Published: May 2010

Cortical activity associated with generating an inference was measured using fMRI. Participants read three‐sentence passages that differed in whether or not an inference needed to be drawn to understand them. The inference was based on either a protagonist's intention or a physical consequence of a character's action. Activation was expected in Theory of Mind brain regions for the passages based on protagonists' intentions but not for the physical consequence passages. The activation measured in the right temporo‐parietal junction was greater in the intentional passages than in the consequence passages, consistent with predictions from a Theory of Mind perspective. In contrast, there was increased occipital activation in the physical inference passages. For both types of passage, the cortical activity related to the reading of the critical inference sentence demonstrated a recruitment of a common inference cortical network. This general inference‐related activation appeared bilaterally in the language processing areas (the inferior frontal gyrus, the temporal gyrus, and the angular gyrus), as well as in the medial to superior frontal gyrus, which has been found to be active in Theory of Mind tasks. These findings are consistent with the hypothesis that component areas of the discourse processing network are recruited as needed based on the nature of the inference. A Protagonist monitoring and synthesis network is proposed as a more accurate account for Theory of Mind activation during narrative comprehension. Hum Brain Mapp, 2011. © 2010 Wiley‐Liss, Inc.
The role of puberty in the developing adolescent brain
Authors: Blakemore Sarah‐Jayne , Burnett Stephanie , Dahl Ronald E.
Published: May 2010

Adolescence refers to the period of physical and psychological development between childhood and adulthood. The beginning of adolescence is loosely anchored to the onset of puberty, which brings dramatic alterations in hormone levels and a number of consequent physical changes. Puberty onset is also associated with profound changes in drives, motivations, psychology, and social life; these changes continue throughout adolescence. There is an increasing number of neuroimaging studies looking at the development of the brain, both structurally and functionally, during adolescence. Almost all of these studies have defined development by chronological age, which shows a strong—but not unitary—correlation with pubertal stage. Very few neuroimaging studies have associated brain development with pubertal stage, and yet there is tentative evidence to suggest that puberty might play an important role in some aspects of brain and cognitive development. In this paper we describe this research, and we suggest that, in the future, developmental neuroimaging studies of adolescence should consider the role of puberty. Hum Brain Mapp, 2010. © 2010 Wiley‐Liss, Inc.
Is the ADHD brain wired differently? A review on structural and functional connectivity in attention deficit hyperactivity disorder
Authors: Konrad Kerstin , Eickhoff Simon B.
Published: May 2010

In recent years, a change in perspective in etiological models of attention deficit hyperactivity disorder (ADHD) has occurred in concordance with emerging concepts in other neuropsychiatric disorders such as schizophrenia and autism. These models shift the focus of the assumed pathology from regional brain abnormalities to dysfunction in distributed network organization. In the current contribution, we report findings from functional connectivity studies during resting and task states, as well as from studies on structural connectivity using diffusion tensor imaging, in subjects with ADHD. Although major methodological limitations in analyzing connectivity measures derived from noninvasive in vivo neuroimaging still exist, there is convergent evidence for white matter pathology and disrupted anatomical connectivity in ADHD. In addition, dysfunctional connectivity during rest and during cognitive tasks has been demonstrated. However, the causality between disturbed white matter architecture and cortical dysfunction remains to be evaluated. Both genetic and environmental factors might contribute to disruptions in interactions between different brain regions. Stimulant medication not only modulates regionally specific activation strength but also normalizes dysfunctional connectivity, pointing to a predominant network dysfunction in ADHD. By combining a longitudinal approach with a systems perspective in ADHD in the future, it might be possible to identify at which stage during development disruptions in neural networks emerge and to delineate possible new endophenotypes of ADHD. Hum Brain Mapp, 2010. © 2010 Wiley‐Liss, Inc.
Relationship between hydraulic and basic properties for irrigated soils in southeast Australia
Authors: Selle Benny , Wang Q. J. , Mehta Brijesh
Published: May 2010

This paper examines the potential of soil maps and spatial information on basic soil properties for predicting soil hydraulic properties in the Shepparton irrigation region (SE Australia). For this purpose, the relationship between locally measured soil hydraulic properties and basic soil properties, and soil categories was analyzed. Pedotransfer functions developed for Australian soil were tested. Furthermore, association of field‐scale final infiltration rates with basic soil properties was investigated. Water‐retention properties, and in particular subsoil water‐retention properties, were significantly correlated with readily available basic soil properties. Spearman's rank correlation coefficients were particularly high for clay content, bulk density, and the sum of exchangeable cations Ca2+, Mg2+, Na+, and K+. Water‐retention properties were adequately predicted using Australian pedotransfer functions. Water‐transmission properties such the saturated conductivity and the final infiltration rate were overall poorly correlated with basic physical and chemical properties. Generally, median water‐transmission properties did not significantly change with soil groups and “within‐paddock variability” accounted for over half of the “within‐soil‐type variability” for many soil types. We concluded that it is feasible to regionalize water‐retention properties for the Shepparton irrigation region using basic physical and chemical soil properties, whereas the information on basic soil properties and from soil maps was insufficient to reliably estimate water‐transmission properties. It is demonstrated why field‐scale estimates of final infiltration rates, obtained by fitting a model for surface irrigation to field measurements of advance, depletion, and recession, may be better correlated with basic soil properties.
Physiological characteristics of selenite uptake by maize roots in response to different pH levels
Authors: Zhang Lianhe , Yu Feiyan , Shi Weiming , Li Youjun , Miao Yanfang
Published: May 2010

In selenite solutions, H2SeO3, HSeO$ _3^- $, and SeO<$>_3^{2‐}<$> are in equilibrium in proportions that vary with solution pH. The physiological characteristics of selenite uptake were studied with excised roots of maize (Zea mays L.) seedlings at pH 3.0, 5.0, and 8.0. The results showed that 0.10 mM 2,4‐dinitrophenol (DNP), 1.0 mM sodium fluoride (NaF), and a temperature of 4°C inhibited selenite uptake by maize roots by 16%, 20%, and 23% at pH 3.0, by up to 80%, 79%, and 78% at pH 5.0, and by 5%, 9%, and 16% at pH 8.0. Hence, selenite may enter roots at pH 5.0 in an energy‐dependent manner, in contrast to pH 3.0 and 8.0. The uptake kinetics for selenite were determined for excised roots of maize, and the curves were linear at pH 3.0 and 8.0, but saturated at pH 5.0, showing that carrier‐mediated uptake of selenite occurred at pH 5.0, but not at pH 3.0 or 8.0. Further studies showed that HgCl2 and AgNO3 inhibited selenite uptake separately by 81% and 76% at pH 3.0 and indicated that selenite was absorbed by maize roots through aquaporins at pH 3.0. At pH 8.0, anion‐channel inhibitors only inhibited a small fraction of selenite uptake, indicating that the major absorption pathway of SeO<$>_3^{2‐}<$> species into roots was not absorbed passively through anion channels, but might involve other processes. According to these results, it is proposed that selenite uptake occurs via different mechanisms depending on its species in solution in response to pH levels.
Chemical composition of cabbage (Brassica oleracea L. var. capitata) grown on acid sulfate soils
Authors: Fältmarsch Rasmus , Österholm Peter , Jacks Gunnar
Published: May 2010

The purpose of this study was to investigate the influence of soil geochemistry on the concentrations of Ca, K, Mg, P, Co, Ni, Zn, Mn, Cu, and Fe in cabbage (Brassica oleracea L. var. capitata) grown on acid sulfate (AS) soils in Western Finland. A total of 11 topsoil (0–20 cm) and corresponding cabbage samples and three whole‐soil profiles (≈ 0–260 cm) were collected on three agricultural fields. The concentrations of Co and Zn in cabbage were correlated with the NH4Ac‐extractable (easily available) concentrations in the topsoil, indicating that the uptake of these elements in cabbage is largely governed by soil geochemistry. Yet, the concentrations of Co and Zn in cabbage were not in general elevated relative to that of Finnish average values, although some AS soils showed enriched concentrations of these metals in the soil and cabbage. Significant geochemical differences (e.g., oxidation depth, organic‐matter and S content, pH) were observed among the studied AS soils, while, on the other hand, the concentrations of Ca, K, Mg, P, Ni, Mn, Cu, and Fe in cabbage were relatively similar. The hydroxylamine‐extractable concentrations of these elements in the topsoil were not correlated to those in cabbage, suggesting that uptake is not governed by the oxide‐bound fraction of these elements in the soil. Similarly, the easily available concentrations of Ca, P, Ni, Mn, Cu, and Fe in the topsoil were not correlated to those in cabbage, indicating that uptake is independent of the easily available concentrations in the soil. Hence, it is suggested that cabbage can regulate and thus optimize its concentrations of Ca, P, Ni, Mn, Cu, and Fe. Oxidation depth affected neither the easily available concentrations of Co, Ni, Zn, and Mn in the topsoil nor the concentrations in cabbage. However, the subsoil with a lower oxidation depth, which is to a smaller extent affected by leaching, may partly be enriched in these metals. Nevertheless, these showed no increased concentrations in cabbage. Based on these findings, it is suggested that the large amounts of metals mobilized in AS soils are easily lost to drains, subsequently contaminating nearby waterways and estuaries whereas they are only partly enriched in cabbage and other previously studied crops (oat).
Aluminum, manganese, and iron tolerance improves performance of wheat genotypes in waterlogged acidic soils
Authors: Khabaz‐Saberi Hossein , Rengel Zed
Published: May 2010

Waterlogging results in high shoot concentrations of iron (Fe), aluminum (Al), and manganese (Mn) in wheat grown in acidic soil. The verification of this observation in several acidic soils, development of screening techniques, and identification of genotypes differing in tolerance made it possible to test whether tolerance of ion toxicities improves performance of wheat in waterlogged acid soils. Six wheat varieties selected for tolerance/intolerance of Al, Mn, and Fe were grown in three acidic soils (pHCaCl2 4.1–4.3) with or without waterlogging for 40 d. In terms of relative shoot dry weight, Al‐, Mn‐, and Fe‐tolerant genotypes tolerated waterlogging better, outperforming intolerant genotypes by 35%, 53%, and 32%, respectively, across the soils. The Al‐tolerant genotype had up to 1.8‐fold better root growth than the intolerant genotype under waterlogging. Waterlogging increased DTPA‐extractable soil Mn (71%) and Fe (89%), and increased shoot Fe (up to 7.6‐fold) and Al (up to 5.9‐fold) for different genotypes and soils. The Al‐tolerant genotype maintained lower tissue concentrations of Al as compared to intolerant genotypes during waterlogging. Waterlogging delayed crop development but distinctly less so in the tolerant than in the intolerant genotypes, thus jeopardizing the capacity of intolerant genotypes to produce yield in Mediterranean climates with dry finish of the season. Pyramiding multiple ion tolerances into current wheat varieties with desirable agronomic and quality characteristics to enhance their performance under waterlogged acid soils should be considered.
From Oil‐Turbine to Model E: Early Days in Retrospect
Authors: Creeth J. Michael
Published: May 2010

This account deals approximately with the period 1940–1960, in which time Svedberg's invention of the first reliable ultracentrifuge was making a great contribution to developments in physical biochemistry. In the 1930's, only at Uppsala could an ultracentrifuge experiment be conducted, but by the 1960's electrically driven machines—the “Model E”—were widely available, particularly in the USA. The instrument was used extensively to follow fractionation methods for purifying proteins and other biological macromolecules and to determine their sedimentation coefficients and molecular weights. Here the author calls upon some of his own experiences, having been able to work with some of the now‐famous contributors to the subject. As an analytical instrument, a good example was the proof by a velocity run that a particular sample of DNA was free of protein. This was essential in allowing the viscosity and titration characteristics to be ascribed to the hydrogen bonds formed between purines and pyrimidines—an observation subsequently proving critical. The Model E was easier to use than the oil‐turbine, but discrepancies at first appeared between values for the sedimentation coefficients found from the two machines. These were subsequently resolved when attention was directed to rotor temperature uncertainties.
Structure and Properties of Phosphorous‐Containing Thermotropic Liquid‐Crystalline Aliphatic–Aromatic Copolyesters
Authors: Serbezeanu Diana , Vlad‐Bubulac Tachita , Hamciuc Corneliu , Aflori Magda
Published: May 2010

A series of thermotropic liquid crystalline aliphatic–aromatic copolyesters derived from various ratios of dodecane‐1,12‐diol (1), terephthaloyl bis‐(4‐oxybenzoyl‐chloride) (2), and 2‐(6‐oxido‐6H‐dibenz〈c,e〉〈1,2〉 oxaphosphorin‐6‐yl)‐1,4‐naphthalene diol (3), has been synthesized. The chemical structures of the monomers and polymers have been confirmed by elemental analyses, and FT‐IR and1H NMR spectroscopy. The mesomorphic properties of polymers have been investigated by differential scanning calorimetry, polarizing optical microscopy, and X‐ray diffraction measurements. The influence of the content of the aliphatic unit on the phase behavior of the polymers has been examined. The polymers that contain >30 mol‐% aliphatic diol showed smectic phases while the polymers that contained <30 mol‐% aliphatic diol displayed nematic phases. The polymers revealed a reversible mesomorphic phase transition, wide mesophase temperature ranges, and high thermal stability. The degree of crystallinity increased upon increasing the content of aliphatic moieties. The char yield at high temperature increased by increasing the content of phosphorous‐containing bisphenol.

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Copper(0)‐Mediated Living Radical Polymerization of Methyl Methacrylate in a Non‐polar Solvent
Authors: Hornby Ben D. , West Andrew G. , Tom Jessica C. , Waterson Carl , Harrisson Simon , Perrier Sébastien
Published: May 2010

The metal catalyzed polymerization of methyl methacrylate using Cu(0) as the catalyst source has been investigated in toluene. This work looks at polymerizations in a non‐polar medium allowing control over the molecular weight and polydispersity with a 4‐fold reduction in catalyst concentration versus conventional ATRP, while the use of an active ligand allows the reaction to proceed at room temperature. The use of an excess of PMDETA ligand allows for high conversions, and the addition of a small amount of CuBr2 enhances living characteristics, enabling efficient chain extension.

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Deutsche Wissenschaftler in den USA: bleiben oder zurückkehren?
Authors: Simons Katja
Published: May 2010

Über 5000 promovierte Nachwuchswissenschaftler/innen aus Deutschland arbeiten in den USA an Hochschulen und nationalen Forschungseinrichtungen. Um den Strom der Talente nach Deutschland umzulenken, brauchen Nachwuchswissenschaftler/innen hier eine attraktive Alternative. Vor allem müssen ihnen klare Perspektiven für eine dauerhafte Beschäftigung in Deutschland aufgezeigt werden.
Konkurrenz aus China bedroht die europäische Chemieindustrie
Authors: Festel Gunter , Capital Festel , Bell Carl‐Martin , Müller Heinz
Published: May 2010

Chinesische Unternehmen versuchen immer stärker, ausländische Märkte zu erschließen. Dabei könnten sie in Europa zu einer Konkurrenz für heimische Chemieunternehmen heranwachsen.
Zentrum und Verbund
Authors: Thunig Christine
Published: May 2010

Bayreuth: Ein neues Labor für die Forschung an Kolloiden, Polymeren und Grenzflächen und ein neues Labor für die Wirkstoffforschung.
Molecular Modelling für chemisch‐technische Anwendungen
Authors: Sundmacher Kai , Voigt Andreas , Förster Andreas
Published: May 2010

Ende September 2004 fand bei der Dechema in Frankfurt ein Workshop „Molecular Modelling für chemisch‐techniche Anwendungen”︁ statt. An der zweitägigen Veranstaltung nahmen 70 Fachleute, davon 20 aus der Industrie teil. 14 Vorträge und 22 Poster zeigten den Status des Molecular Modelling in Hochschulen und Forschungsinstituten; Anwender aus der Industrie präsentierten Einsatzgebiete und Perspektiven der Technik. Der Workshop bildete den Auftakt zur Gründung eines Dechema‐Arbeitskreises „Molekulare Modellierung und Simulation für Prozeß‐ und Produktdesign”︁.
Chance für Mitarbeiter und Unternehmen
Authors: Neubauer Uta
Published: May 2010

Vom Patentrecht bis zu Sicherheitsmaßnahmen in Gentech‐Laboratorien ‐ mit fast 80 Seminaren deckt das GDCh‐Fortbildungsprogramm 2005 die gesamte Chemie ab.
Gerätebau am Standort Deutschland ist möglich
Authors: Rittgerodt Bernword
Published: May 2010

Kann man in Deutschland überhaupt noch wirtschaftlich produzieren? Firmeninhaberin Alexandra Knauer meint: „Ja”︁. Für ihr Engagement hat sie die Stadt Berlin mit dem Unternehmerinnenpreis 2004 ausgezeichnet.
Mehr als verkaufen ‐ Chemiker im technischen Vertrieb
Authors: Steck Oliver
Published: May 2010

Ein Anbieter von Produkten und Services für die Wirkstofffindung, beschreibt die Arbeit eines „Account Executive”︁ so: „In seinem Vetriebsgebiet akquiriert er neue Kunden, baut das Geschäft mit bestehenden Kunden aus und trägt so zum Erfolg des Unternehmens bei. „Aber was steckt dahinter?”︁
Röntgenanalytik für Kunstwerke und Kulturgüter
Authors: Denker Andrea , Hahn Oliver , Merchel Silke , Radtke Martin , Kanngießer Birgit , Malzer Wolfgong , Stege Heike
Published: May 2010

Naturwissenschaftler arbeiten mit Archäologen, Kunsthistorikern und Restauratoren zusammen, um Materialinformationen über Kunstwerke und archäologische Artefakte gewinnbringend mit den Erkenntnissen aus Altertumsforschung, Kunstgeschichte und Denkmalpflege zu verbinden. Röntgenfluoreszenz und Röntgenemission sind die Methoden der Wahl, wenn wertvolle und fragile Objekte zerstörungsfrei zu untersuchen sind.
Getting the balance right
Authors: Harries‐Rees Karen
Published: May 2010

Innovation is a key factor in corporate success. It can take 10–30 years for an invention in the chemical industry to become a big product. With the money invested over that time, the new line needs a turnover of at least 50 million Euro.
Qualität zählt: zehn Jahre Chemistry
Authors: Karger Gerhard
Published: May 2010

Mit der Unterstützung von 14 europäischen chemischen Fachgesellschaften und immer mehr Topautoren aus aller Welt, die das Full‐Paper‐Journal als Forum für ihre Arbeiten nutzen, ist Chemistry glänzend aufgestellt und für die Zukunft gerüstet. Das 10‐jährige Jubiläum der Zeitschrift bietet Anlass zu einer Zwischenbilanz: Chefredakteur Neville Compton im Gespräch mit den Nachrichten aus der Chemie.
Der Bakterien‐Außenbordmotor
Authors: Groß Michael
Published: May 2010

Die genaue Funktionsweise des im Bakterienreich weitverbreiteten Geißelantriebs war lange Zeit ein Rätsel. Jetzt arbeitet sich ein Team japanischer Strukturbiologen von der Geißel über das Gelenk zum eigentlichen Antriebsaggregat vor.
Festkolloquium: The Molecular Basis of Catalysis
Authors: Leitner Walter
Published: May 2010

Anfang Dezember 2004 trafen sich in Aachen etwa 200 Chemiker aus Industrie und Hochschule, darunter viele Alumni der Aachener Chemie, um die molekularen Grundlagen der Katalyse zu diskutieren. Zum Symposium im Ludwig Forum für Internationale Kunst hatte das Institut für Technische und Makromolekulare Chemie (ITMC) der RWTH Aachen anlässlich des 70. Geburtstages seines ehemaligen Direktors Wilhelm Keim eingeladen. Mit dem Tagungsort erwiesen die Veranstalter der Begeisterung des Jubilars für die moderne Kunst ihre Reverenz.
2. Doktorandenseminar über molekular geprägte Polymere
Authors: Emgenbroich Marco , Hall Andrew J.
Published: May 2010

Zum zweiten Ma1 hat die Arbeitsgruppe von Börje Sellergren ein Doktorandenseminar zum Thema „molekular geprägte Polymere”︁ durchgeführt. 33 Teilnehmer aus ganz Europa kamen Anfang Dezember 2004 an die Universität Dortmund.
Formaldehyd‐Immissionsmessung und Ozon
Authors: Creutznacher Harald , Veith Anke , Stoll Sandra
Published: May 2010

Ozonabscheider verhindern, dass organische Luftinhaltsstoffe bei der Probennahme mit Ozon reagieren und dies die Analysen verfälscht. Auch für die Formaldehyd‐Bestimmung sind Ozonabscheider unabdingbar.
Gebundene Pestizidrückstände in Flusssedimenten erfassen
Authors: Kronimus Alexander , Schwarzbauer Jan
Published: May 2010

Zahlreiche Umweltkontaminanten wechselwirken stark mit der Matrix von Flusssedimenten, so dass erhebliche Anteile dieser Stoffe nicht extrahierbar sind. Dieser Prozess der Immobilisierung ist reversibel ‐ auch nach Jahren können gebundene Rückstände wieder ins Wasser gelangen.
Anorganische Chemie 2004
Authors: Himmel Hans‐Jörg , Hoge Berthold , Glaser Thorsten , Kersting Berthold
Published: May 2010

Ionische und subvalente Verbindungen, molekulare Cluster und die Renaissance der Azide markieren den Fortschritt in der Hauptgruppenelementchemie. Die Koordinationschemie wächst „über das Molekül hinaus”︁. Proteinkristallographie und Modellstudien sind die Motoren der Bioanorganischen Chemie.
Biochemie 2004
Authors: Skerra Arne , Eichinger Andreas , Jäschke Andres , Helm Mark , Marx Andreas , Strerath Michael
Published: May 2010

Das rationale Proteindesign mit rechnergestützen Methoden ist in eine überraschend produktive Phase getreten: Nun können stabilisierte Proteine und sogar künstliche Enzyme experimentell realisiert werden. Röntgenstrukturanalysen machen die Erkennung von Nucleinsäuren durch Proteine in der DNA‐Replikation und bei Prozessen der RNA‐Interferenz im molekularen Detail sichtbar.
Technische Chemie 2004
Authors: Christophliemk Peter , Liauw Marcel , Liese Andreas
Published: May 2010

Ionische Flüssigkeiten und die Nanotechnologie sind in der Technischen Chemie auf dem Vormarsch. Impulse für die homogene Katalyse geben Übergangsmetallkomplexe und Organokatalysatoren; die Biokatalyse steht im Zeichen der Weißen Biotechnologie. Die Verfahrenstechnik profitiert von einer immer besseren Modellierung komplexer Prozesse. Spezialmembranen und mikrostrukturierte Apparate erschließen weitere Anwendungsfelder.
Der GDCh‐Forschungs‐ und Technologieführer
Authors: Kießling Leonhard , Moritz Florian , Schunk Axel
Published: May 2010

Die GDCh legt ihren 1994 erschienen Forschungsführer neu auf ‐ diesmal nicht in gedruckter Version, sondern als Datenbank. Damit sie die chemische Forschungslandschaft möglichst vollständig wiedergibt, sind alle Wissenschaftler aufgefordert, sich zu beteiligen, indem sie sich eintragen.
Trockene Destillation und „Arme‐Leute‐Wein”︁
Authors: Rasch Anja , Fließ Anja , Bengs Holger
Published: May 2010

Der Werdegang von Johann Rudolph Glauber, dem ersten Industrie‐Chemiker, fasziniert auch noch 400 Jahre nach seinem Geburtstag.
Peptidantibiotika vom molekularen Fließband
Authors: Dürfahrt Thomas , Marahiel Mohamed A.
Published: May 2010

Bei der Herstellung komplexer biologisch aktiver Peptide stößt die Synthesechemie an ihre Grenzen. Hilfe verspricht die Analyse von Funktionszusammenhängen in der Natur: Mikroorganismen produzieren die medizinisch relevanten Verbindungen mit nichtribosomalen Peptidsynthetasen. Ein variabler modularer Aufbau und die gentechnische Modifikation dieser Enzymkomplexe eröffnen Möglichkeiten z. B. bei der Entwicklung potenter Antibiotika.
Stiften und forschen
Authors: Karger Gerhard , Zbikowski Frauke , Weiner Barbara
Published: May 2010

Wie lassen sich Anliegen der Hochschul‐ und Industrieforschung unter lokal und weltweit rapide sich ändernden Bedingungen vereinen? Alfred Oberholz, im Degussa‐Vorstand für Forschung und Entwicklung verantwortlich, Magnus Rüping, Degussa‐Stiftungsprofessor am Fachbereich Chemische und Pharmazeutische Wissenschaften der Universität Frankfurt und Harald Schwalbe, Dekan des Fachbereichs, suchen im Nachrichten‐Interview nach Antworten.
Anmerkungen zu den Descartes‐Preisen
Authors: Schorsch Gilbert
Published: May 2010

Bilanz nach fünf Jahren EU‐Forschungspreis: Das Fach Chemie ist bei den ausgezeichneten Projekten sehr gut vertreten; gemeinsam mit Frankreich glänzt Deutschland aber in der Riege der Preisträger durch Abwesenheit. Will die EU‐Kommission wirklich die Konkurrenzfähigkeit Europas fördern, muss sie die Ausschreibung öffnen, sie besser bekannt machen und Vertreter aus Wirtschaft und Gesellschaft bei der Auswahl der Projekte stärker beteiligen.
Raman‐Spektroskopie mit Monolagenempfindlichkeit
Authors: Esser Norbert , Wagner Veit
Published: May 2010

Resonante Raman‐Spektroskopie analysiert anorganische und organische Schichten bis in kleinste Bedeckungsbereiche und empfiehlt sich als Untersuchungsmethode in der technisch immer wichtigeren Funktionalisierung von Oberflächen.
Chemie‐Nachwuchsgruppenleiter in Freiburg
Authors: Oestreich Martin
Published: May 2010

Zum zweiten Mal trafen sich im Februar die durch das Emmy‐Noether‐Programm der Deutschen Forschungsgemeinschaft (DFG) geförderten Chemie‐Nachwuchsgruppenleiter. Zu diesem Treffen hatte Martin Oestreich an das Institut für Organische Chemie und Biochemie der Universität Freiburg eingeladen. Das Interesse am gegenseitigen wissenschaftlichen und auch persönlichen Erfahrungsaustausch hält weiter an.
Chemikalienbewertung vor Reach
Authors: Greim Helmut
Published: May 2010

Insgesamt hat Deutschland einen vergleichsweise hohen Beitrag zur Altstoffbewertung geleistet und große Erfahrungen bei der Identifzierung und Bewertung von Chemikalien gesammelt. Diese Erfahrungen fließen in die europäischen und internationalen Programme ein.
Aus einem Guss
Authors: Huber Christian
Published: May 2010

Aufgrund ihrer einzigartigen Struktur und ihrer für chromatographische Trennungen günstigen Eigenschaften gelten monolithische stationäre Phasen als eine neue Generation von Packungsmaterialien für die Hochleistungs‐Flüssigchromatographie.
Schnelle HPLC‐Trennungen
Authors: Lamotte Stefan
Published: May 2010

Kurze Säulen, die mit Trägermaterialien mit Partikeldurchmessern unterhalb von 2 μm gefüllt sind, beschleunigen HPLC‐Analysen deutlich. Die schnelle HPLC ist inzwischen so robust, dass sie sich für die Routineanalytik eignet.
Analytik unter der Sonne Floridas
Authors: Karst Uwe
Published: May 2010

Unter dem Motto„Everything Science Under the Sun”︁ trafen sich vom 27. Februar bis zum 4. März In Orlando, Florida, analytische Chemiker aus aller Welt zur 56. Pittcon.
So punkten Studenten mit Bologna
Authors: Weiner Barbara
Published: May 2010

Viele Hochschulen und Institute führen derzeit das Leistungspunktesystem ein, ein zentrales Ziel in der Strukturreform der europäischen Hochschulen. Noch sind allerdings die wenigsten Studenten und wissenschaftlichen Mitarbeiter mit diesem System vertraut.
Mikroreaktoren zur Synthese und Reaktionsoptimierung
Authors: Jensen Klavs F. , Seeberger Peter H.
Published: May 2010

Labore ohne Glasgeräte? Werden organische Chemiker ihre Synthesen bald in Reaktorchips durchführen, die wie Computer‐Hardware organisiert sind, in Strukturen aus Silicium, Glas oder Stahl? Die Fortschritte in der Mikroreaktionstechnik der letzten zehn Jahre legen solche Fragen nahe ‐ und Umsetzungen in Mikroreaktoren gelingen häufig mit besseren Ausbeuten, erhöhter Sicherheit und weniger Zeit‐ und Materialaufwand.
Wundverschluss durch Biopolymerisation
Authors: Pohnert Georg
Published: May 2010

Die einzellige Grünalge Caulerpa taxifolia, die mehrere Meter lang werden kann, ist ein Meister der Selbstheilung: Sie versiegelt Wunden in Sekundenschnelle durch Bildung eines gelatineartigen Verschlusses. Unter Enzymkatalyse bildet sich zunächst aus einem Algen‐Metabolit ein reaktiver Dialdehyd, der Proteine zu einem polymeren Netzwerk verknüpft ‐ ein neues Prinzip der Biopolymerbildung.
The right women for the job
Authors: Harries‐Rees Karen
Published: May 2010

Julia Higgins talks to Karen Harries‐Rees about her many roles and plans for the future.
Schutzrechtsstrategien in der Chemie
Authors: Schneider Michael
Published: May 2010

Patente schützen, sind aber teuer. Mit entsprechenden Strategien lassen sich die Kosten im Rahmen halten.
33. Arbeitstagung Flüssigkristalle
Authors: Kitzerow Heinz‐S.
Published: May 2010

Mitte März trafen sich 130 Naturwissenschaftler und Ingenieure in Paderborn zur 33. Arbeitstagung Flüssigkristalle. Die Tagung findet im Frühjahr jedes Jahres statt und wird veranstaltet von der Deutschen Flüssigkristallgesellschaft, einer Arbeitsgemeinschaft in der Deutschen Bunsengesellschaft für Physikalische Chemie. In diesem Jahr standen 27 Vorträge und 54 Posterbeiträge auf dem Programm. Tagungssprache war Englisch. Die Teilnehmer kamen aus Algerien, Deutschland, England, Frankreich, Holland, Italien, Polen, der Schweiz, Spanien und den USA.
Dendrimer‐Tagung in Heidelberg
Authors: Enders Markus
Published: May 2010

Unter dem Titel „Dendrimers: Platforms for Chemical Functionality”︁ fand Mitte März in Heidelberg ein zweitägiges Symposium zur Dendrimerforschung statt. 100 Teilnehmer informierten sich in zehn Plenarvorträgen und anhand von 30 Postern über aktuelle Entwicklungen und Ergebnisse. Veranstalter der Tagung waren die Deutsche Akademie der Naturforscher Leopoldina und der Heidelberger Sonderforschungsbereich 623 ‐ „Molekulare Katalyse”︁.
Ketten und Löcher in Wasser
Authors: Zahn Dirk
Published: May 2010

Wasser ist allgegenwärtig und lebenswichtig, ein einzelnes Wassermolekül einfach aufgebaut. Dennoch sind wir noch weit davon entfernt, alle Eigenschaften dieses Stoffs im Detail zu verstehen. Die Komplexität des Wassers, zu der Phänomene wie die Autoprotolyse und die spontane Bildung von Kavitäten gehören, beruht auf den mannigfaltigen Anordnungsmöglichkeiten eines Kollektivs von mehreren Wassermolekülen.
DNA‐Analytik ‐ trivial?
Authors: Groß Michael
Published: May 2010

Gentests sind alltäglich geworden, doch in den molekularbiologischen Labors werden die Grenzen des Machbaren weiter verschoben.
Lust auf Zukunft
Authors: Guggolz Ernst
Published: May 2010

„Chemie schafft neue Strukturen”︁ ‐ das Motto der GDCh‐Jahrestagung die chemische Industrie. Mit welchen Strukturen die BASF in den letzten 140 Jahren die BASF geblieben und The Chemical Company geworden ist, erläutert im Gespräch der Vorstandsvorsitzende Jürgen Hambrecht.