bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effects of buckwheat growth on variation of aluminum and major metals in root‐zone soil solutions
Authors: Fu Chen Rong , Fang Shen Ren , Di Yang Xiao , Wang Xianlong 
Published: July 2010

AbstractThe variation in and relationships between aluminum and other major metals including Ca, Mg, Mn, and K in root‐zone soil solutions were studied by growing buckwheat (Fagopyrum esculentum Moench. cv. Jiangxi), an Al accumulator, in pots filled with an acid soil amended with CaCO3 and unamended controls with a preinstalled nondestructive soil‐solution sampler. Soil solutions were collected every 7 d with a syringe connected to the sampler. The results showed that pH of the soil solution was not the only factor controlling the concentration of Al. Significant positive linear correlations were found between Al and Ca as well as between Al and Mg in soil solutions from the controls. The ratio of base cations (BC, Ca+Mg) to Al might partly explain the high Al resistance of buckwheat. Oxalate secretion from roots significantly activated Al in acid soils, which may be important for changes of Al in soil solutions, but it also caused decreased concentrations of Ca, Mg, and Mn. It is concluded that the variation of metal concentrations including Al, Ca, Mg, and Mn is a holistic effect involving competition for exchange sites among Ca, Mg, H, and Al, the chelation by oxalate secreted from roots, and metal uptake by buckwheat.
Benzene polycarboxylic acids—A ubiquitous class of compounds in soils
Authors: Haumaier Ludwig 
Published: July 2010

AbstractBlack carbon (BC) occurs ubiquitously in the environment. Its oxidation in the laboratory yields a suite of benzene polycarboxylic acids (BPCAs), suggesting similar oxidation products in soils. Since only for a few soils the occurrence of BPCAs in the free form has been documented, screening for them in a broad range of contrasting soils was conducted. They were extracted from soil samples with 0.5 M NaOH and quantified using gas chromatography–mass spectrometry. As expected, BPCAs turned out to be as ubiquitous as BC. They were detected not only in every soil sample investigated so far, but also in samples from drill cores up to a depth of 10 m and in recently deposited calcareous tufa. The concentrations covered a range similar to that of some phenolic acids. The range exceeded those reported for low‐molecular‐weight aliphatic acids or simple sugars in soils. The distribution of BPCAs in soil profiles indicated a considerable potential of translocation within, and export from, soil, in particular of benzene hexacarboxylic (mellitic) acid. Mellitic acid may therefore be present in almost any geochemical sample affected by seepage water from soils. Its high water solubility and strong metal‐complexing ability suggest it may be involved in metal‐transport processes, at least on geological timescales.
New data on speleothem deposition and palaeoclimate in Britain over the last forty thousand years
Authors: Atkinson T. C. , Lawson T. J. , Smart P. L. , Harmon R. S. , Hess J. W. 
Published: July 2010

Abstract230Th/234U dates are presented for 26 speleothems from three areas in Britain: Assynt, N.W. Scotland; N.W. Yorkshire; Mendip Hills, Somerset. These dates suggest that speleothem growth was widespread but rare in the period from 40 to 26 Ka, absent from 26 to 15 Ka, and abundant from 15 Ka to the present. The absence of speleothems between 26 and 15 Ka is attributed to glaciation in Yorkshire and Assynt and, tentatively, to continuous permafrost development in the Mendip Hills. The occurrence of speleothems before 26 Ka places restrictions on the extent of any ice sheet which may have been present in Scotland, and indicates that N.W. Scotland was not subjected to continuous permafrost at that time.
Adsorption of 2‐amino‐5‐cyanopyridine on a gold surface as probed by surface‐enhanced Raman spectroscopy
Authors: Xu Min‐Min , Yuan Ya‐Xian , Yao Jian‐Lin , Han San‐Yang , Wang Mei , Gu Ren‐Ao 
Published: July 2010

AbstractThe adsorption of 2‐amino‐5‐cyanopyridine (2‐ACP) was investigated in solution at different pH values by in situ surface‐enhanced Raman scattering (SERS) spectroscopy combined with the electrochemical method. The assignments of the main bands were first performed on the basis of the spectral features of similar compounds and with the help of density functional theory calculations. The results revealed that the adsorption and the interfacial structure of 2‐ACP on the Au electrode depended on the applied potential and the pH values of the solution. In the natural solution, 2‐ACP was adsorbed on the surface with a vertical orientation by the CN group from − 0.4 to − 1.0 V, whereas in the − 0.4 to 0.8 V range, the N atom of the pyridine ring was bound to the surface. A transition region for the reorientation of the two adsorption modes was observed from − 0.8 to − 0.4 V. A flat configuration was preferred at an extremely negative potential. A similar surface adsorption behavior was observed in the alkali environment, while the Stark effect slope decreased because of the adsorption of OH−. Due to the protonation of N atom in the acidic solution, the potential region for the coexistence of two configurations ranged from − 0.4 to 0.2 V. Additionally, a similar adsorption configuration was proposed on the Au colloids at various pH values. The results revealed that the adsorption behavior became more complex on colloidal surfaces than that on a rigid electrode surface. Copyright © 2010 John Wiley & Sons, Ltd.
Dropping macadamia nuts‐in‐shell reduces kernel roasting quality
Authors: Walton David A , Wallace Helen M 
Published: July 2010

AbstractBACKGROUND: Macadamia nuts (‘nuts‐in‐shell’) are subjected to many impacts from dropping during postharvest handling, resulting in damage to the raw kernel. The effect of dropping on roasted kernel quality is unknown. Macadamia nuts‐in‐shell were dropped in various combinations of moisture content, number of drops and receiving surface in three experiments. After dropping, samples from each treatment and undropped controls were dry oven‐roasted for 20 min at 130 °C, and kernels were assessed for colour, mottled colour and surface damage.RESULTS: Dropping nuts‐in‐shell onto a bed of nuts‐in‐shell at 3% moisture content or 20% moisture content increased the percentage of dark roasted kernels. Kernels from nuts dropped first at 20%, then 10% moisture content, onto a metal plate had increased mottled colour. Dropping nuts‐in‐shell at 3% moisture content onto nuts‐in‐shell significantly increased surface damage. Similarly, surface damage increased for kernels dropped onto a metal plate at 20%, then at 10% moisture content.CONCLUSION: Postharvest dropping of macadamia nuts‐in‐shell causes concealed cellular damage to kernels, the effects not evident until roasting. This damage provides the reagents needed for non‐enzymatic browning reactions. Improvements in handling, such as reducing the number of drops and improving handling equipment, will reduce cellular damage and after‐roast darkening. Copyright © 2010 Society of Chemical Industry
Hypoxia inducible factor‐1α gene polymorphism G1790A and its interaction with tobacco and alcohol consumptions increase susceptibility to hepatocellular carcinoma
Authors: Hsiao Pei‐Ching , Chen Mu‐Kuan , Su Shih‐Chi , Ueng Kwo‐Chang , Chen Yi‐Chen , Hsieh Yi‐Hsien , Liu Yu‐Fan , Tsai Hsiu‐Ting , Yang Shun‐Fa 
Published: July 2010

AbstractBackground and ObjectivesThe aim of this study was to examine the potential associations of two hypoxia inducible factor‐1α (HIF‐1α) gene polymorphisms, C1772T and G1790A, with the susceptibility and clinicopathological status of hepatocellular carcinoma.MethodsA total of 449 subjects, including 347 healthy controls and 102 patients with hepatocellular carcinoma, were recruited in this study and subjected to polymerase chain reaction–restriction fragment length polymorphism (PCR‐RFLP) analyses to estimate the impact of these two polymorphic variants on hepatocellular carcinoma.ResultsG1790A heterozygotes showed a higher risk for hepatocellular carcinoma, compared with GG genotypes after adjusting for other confounders (AOR = 3.97; 95%CI = 1.70–9.22), indicating a significant association between hepatocellular carcinoma susceptibility and G1790A polymorphism. Moreover, results also revealed the presence of synergistic effect between gene polymorphism of HIF‐1α G1790A and environmental risk factors, such as tobacco and alcohol consumptions while there was no significant association between HIF‐1α gene polymorphism and clinicopathological parameters of hepatocellular carcinoma.ConclusionsGenetic polymorphism at G1790A of HIF‐1α is an important factor for determining the susceptibility to hepatocellular carcinoma. The interaction effects of G1790A heterozygotes to tobacco and to alcohol consumption significantly increase the risk to develop hepatocellular carcinoma. J. Surg. Oncol. 2010;102:163–169. © 2010 Wiley‐Liss, Inc.
Molecular Weight Distribution Evaluation of Polysaccharides and Glycoconjugates Using Analytical Ultracentrifugation
Authors: Harding Stephen E. , Abdelhameed Ali Saber , Morris Gordon A. 
Published: July 2010

AbstractWe review here the advances that have been made in methodology using the analytical ultracentrifuge for characterising polydisperse polymer systems with a quasi‐continuous distribution of molecular weight. These advances include improved ways of defining the weight and z‐average molecular weights of a distribution from sedimentation equilibrium experiments and hence the ratio $M_{{\rm z}} /M_{{\rm w}} $, off‐line calibration of size exclusion chromatography by sedimentation equilibrium and conversion of a sedimentation coefficient distribution into a molecular weight distribution. Although these methods are applicable to other polymeric systems, we focus on polysaccharides, mucins and other glycoconjugates, systems which particularly benefit from the availability of recently available long optical path length cells for the minimisation of complications through thermodynamic non‐ideality.
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Drought classification in Northern Serbia based on SPI and statistical pattern recognition
Authors: Stricevic Ruzica , Djurovic Nevenka , Djurovic Zeljko 
Published: July 2010

AbstractThis paper proposes a procedure for decision‐making regarding the extent to which a certain geographical region is affected by drought. Professional circles generally recognize the Standardized Precipitation Index (SPI) as a good indicator of a drought event. However, as a result of varying precipitation levels due to various local geographical, climatic, vegetational and other factors, this indicator is determined based on precipitation measurements and different meteorological centres within the same administrative region often generate different SPI values, even when the geographical distance between them is small. During a dry period, various local authorities, ministries of agriculture or governments have to make important decisions about, for example, declaring disasters, subsidizing farmers for certain crops, or providing financial aid to agricultural producers, based on voluminous and diverse data about local precipitation, the yield of various crops, or the condition of the soil. This paper proposes an automated methodology for such decision‐making, which can be used as a support tool by decision‐makers. The methodology is based on the SPI and statistical pattern recognition methods (dimension reduction and classifier design based on the desired output). The entire procedure is illustrated using Vojvodina, a region in Serbia in the southern portion of the Pannonian Plain, as a case study. The proposed algorithm is not subject to any constraints with regard to geographical locations of regions, their surface areas, or inter‐relationships. Copyright © 2010 Royal Meteorological Society
Temperature‐independent fiber bragg grating tilt sensor
Authors: Ni Kai , Dong Xinyong , Jin Yongxing , Xu Haisong 
Published: July 2010

AbstractA novel fiber Bragg grating (FBG) tilt sensor is proposed to detect the magnitude and the direction of a two‐dimensional inclination by using four FBGs. High angle sensitivity and measurement resolution have been achieved, and the temperature effect has been eliminated completely without additional temperature compensation schemes. Experimental results verified the feasibility of the proposed idea. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52:2250–2252, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25425
Temperature‐independent vibration sensor with a fiber Bragg grating
Authors: Zhou Wenjun , Dong Xinyong , Shen Changyu , Zhao Chun‐Liu , Chan Chi Chiu , Shum Ping 
Published: July 2010

AbstractA novel temperature‐independent vibration sensor based on a fiber Bragg grating (FBG) is demonstrated.The FBG was glued in a slanted direction onto the lateral side of a right‐angled triangle cantilever beam. Vertical vibration applied to the cantilever beam leads to a periodical variation of bending curvature along the beam length. As a result of beam bending, the FBG is chirped and its reflection bandwidth and optical power change with the deflection of the beam. Experimental results were compared with the data of vibration measurement of a conventional resistance strain gauge. Good agreement has been achieved. The sensor is temperature independent, owning to the temperature‐independence nature of the reflection bandwidth and optical power of the FBG. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52:2282–2285, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25429
Comparison between analytical and neural approaches for multibias small signal modeling of microwave‐scaled FETs
Authors: Marinković Zlatica , Crupi Giovanni , Caddemi Alina , Marković Vera 
Published: July 2010

AbstractSmall signal models of microwave field‐effect transistors (FETs) can be obtained by using different modeling techniques. This article considers two techniques: an analytical approach based on equivalent circuit representation and an optimization approach based on artificial neural networks. Both of the approaches are applied to extract multibias models of scaled microwave FETs. A comprehensive comparison of both techniques considering different modeling aspects is given. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52:2238–2244, 2010; Published online in Wiley InterScience (www. interscience.wiley.com). DOI 10.1002/mop.25432
An internal multiband antenna with zeroth‐order resonator for usb dongle applications
Authors: Yu Yeonsik , Kim Giho , Seong Wonmo , Choi Jaehoon 
Published: July 2010

AbstractA novel multiband inverted‐L (IL) antenna, intended for use in a universal serial bus (USB) dongle, is proposed. The internal antenna that we designed consists of an L‐shaped zeroth‐order resonator (ZOR) and a folded first‐order IL element, and has a compact volume of 30 ×15 ×7 mm. The proposed antenna provides the wide bandwidth necessary for covering long‐term evolution (LTE), digital cellular network (DCN), and personal communication system (PCS)‐1900 frequency bands. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52:2212–2214, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25433
Experiments on wave propagation at 6.0 GHz in a left‐handed waveguide
Authors: Barroso Joaquim J. , Castro Pedro J. , Leite Neto Joaquim P. 
Published: July 2010

AbstractMicrowave propagation in a metallic waveguide loaded with an array of split‐ring resonators is examined both analytically and experimentally. The synthesized combined medium exhibits a frequency band around 6.0 GHz with simultaneously negative values of permittivity and permeability, which allow transmission in an otherwise forbidden band for the hollow waveguide. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52:2175–2178, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25435
Compact ultra‐wideband bandpass filter using defected ground structures
Authors: Lee J. K. , Kim Y.‐S. 
Published: July 2010

AbstractIn this letter, a compact ultra‐wideband (UWB) bandpass filter (BPF) is presented with improved upper stopband performance using six defected ground structures (DGS).The proposed BPF is composed of seven DGSs which are positioned under the input and output microstrip line and coupled double step impedance resonator (CDSIR). By using CDSIR and open loop defected ground structure (OLDGS), we can achieve UWB BPF characteristics, and by using the conventional DGSs under input and output microstrip line, we can improve upper stopband performance. Simulated and measured results are found in good agreement with each other, showing a wide passband from 3.4 to 10.9 GHz, minimum insertion loss of 0.61 dB at 7.02 GHz and the group delay variation is less than 0.4 ns in the operating band while wide upper stopband with more than 30 dB attenuation up to 20 GHz. In addition, the proposed UWB BPF has a compact size. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52:2173–2175, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25436
All‐optical processing toward next generation wavelength agnostic passive optical networks
Authors: Teixeira A. , Costa L. , Wada N. , Chanclou P. , Forin D.M. , Prat J. , Tosi Beleffi G. M. 
Published: July 2010

AbstractA simple, easy to integrate, low‐power consumption optical processing system able to break new ground on passive optical plant deployment realizing the implementation of pioneer multiple telecom operator scenarios is presented and experimentally investigated. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52:2378–2380, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25438
Broadband built‐in antenna with new enclosed 3D coupling feed structure
Authors: Kim Byoung‐Nam , Park Seong‐Ook , Oh Jung‐Keun 
Published: July 2010

AbstractWideband built‐in antenna with an enclosed 3D coupling feed structure for wireless terminals is presented.With the proposed design scheme, a nine‐band built‐in antenna that covers GSM850/GSM900/GPS/DCS1800/PCS1900/WCDMA/WiBro2350/Bluetooth/WiMax 2500 is experimentally tested. This novel nine‐band built‐in handset antenna is developed within the limits of a 40 × 17.5 × 6 mm3 volume, achieving good agreement between measurement and simulation. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52:2306–2309, 2010; Published online in Wiley InterScience (www.interscience. wiley.com). DOI 10.1002/mop.25441
Low power dual transformer injection locked frequency divider using 0.5 μm GaAs E/D‐mode PHEMTs process
Authors: Ke Po‐Yu , Chiu Hsien‐Chin , Fu Jeffrey S. 
Published: July 2010

AbstractThis letter proposes a new divide‐by‐2 injection locked frequency divider (ILFD) fabricated by 0.5 μm GaAs ED‐Mode PHEMTs process and describes the operation principle of the dual‐transformer ILFD. The first transformer is applied to replace two inductors of the cross‐couple LC‐tank oscillator circuit. The injection signal of the ILFD transmits into a transistor through a second transformer, which consisted of a bandpass filter achieving a high injection signal power and wide locking range. The measurement results show that the divider's free‐running frequency were from 6.47 to 9.54 GHz (32.2%) with 3 V supply voltage. With an incident power of 0 dBm, the locking range is 3.07 GHz from the incident frequency 16.41 to 19.45 GHz (15.6%). The measured phase noise of free running VCO is −92.2 dBc/Hz at 1 MHz offset frequency at 9.45 GHz and this value of the locked ILFD is −128.4 dBc/Hz, which is 36.2 dB lower than the free running VCO. The core power consumption was 42 mW. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52:2302–2306, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25442
Augmented equivalence principle algorithm at low frequencies
Authors: Sun L. E. , Chew W. C. , Jin J.M. 
Published: July 2010

AbstractThe present equivalence principle algorithm (EPA) is augmented by introducing charge densities as extra unknowns. This helps to separate the vector potential term and scalar potential term and avoid the imbalance at low frequencies. Current continuity constraint is enforced in both the scattering operator and translation operator. These further form a new augmented EPA equation system. With this technique, the low‐frequency breakdown of EPA is removed. Besides, it serves not only as a stable low‐frequency method but also as a substitute over the whole frequency band. The new scheme is verified by numerical examples. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52:2274–2279, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25443
Enhancement of ultra‐wideband microstrip monopole antenna by using unequal arms V‐shaped slot printed on metamaterial surface
Authors: Elsheak Dalia N. , Iskander Magdy F. , Elsade Hala A. , Abdallah Esmat A. , Elhenawy Hadia 
Published: July 2010

AbstractA novel ultra‐wideband (UWB) printed monopole microstrip patch antenna is presented. The UWB is provided by using unequal V‐shaped slot arms to provide staggered resonance frequencies from different couplings. Second, using modified ground plane to enhance the bandwidth. An impedance bandwidth from 2 to 30 GHz is obtained using HFSS® with discontinuities in this bandwidth. For further enhancement in the bandwidth, antenna gain as well as removing the harmonic frequencies, the embedded electromagnetic band‐gap (EBG) structure is used. The impedance bandwidth reaches 2000%, covering the frequency range 0.5–40 GHz with bandwidth ratio of 80:1. Three different techniques of metamaterial are used, namely using embedded square shapes as artificial magnetic conductor, using embedded uniplanar square EBG structure without via, and, finally, using embedded metallo‐electromagnetic band‐gap structure with via. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52:2203–2209, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25447
Measurement of Stokes parameters of terahertz radiation in terahertz time‐domain spectroscopy
Authors: Dong Hui , Gong Yandong , Olivo Malini 
Published: July 2010

AbstractWe propose a technique for the measurement of Stokes parameters of terahertz radiation in terahertz time‐domain spectroscopy (THz‐TDS). In this technique, a rotatable wire‐grid THz polarizer is placed in front of a two‐contact photoconductive THz detector. Stokes parameters can be measured by making two temporal scans corresponding to two angles of the polarizer. We theoretically demonstrate that the two angles can be −45° and 45° for achieving the statistically best measurement accuracy in a single test. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52:2319–2324, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25450