bluuebunny/crossref_metadata_2025 huggingface dataset:
Influence of Heat Treatment on Flow Behaviour Index of Dairy Cream
Authors: Vekariya Yogeshkumar , Chopde Santosh , Kathiriya Mital , Halder Kumaresh
Published: April 2024

The objective of the experiment was to gather data on the flow behaviour index of dairy cream under different heat treatments and subsequent temperature changes. Dairy cream samples with fat content of 10%, 20%, 30%, 40%, 50% & 60% was subjected to different heat treatments i.e., 80°C/No hold, 85°C/No hold, 90°C/No hold & 95C°/No hold. The flow behaviour index of such heat-treated samples was evaluated at every 10°C upon cooling from 80°C or 70°C as the case may be till 10°C at 250 S-1 shear rate using rheometer. It was observed that at 10°C, 20°C, 30°C and 40°C temperature of measurement, the fat content of cream and the heat treatment applied to the cream demonstrated a significant impact (p<0.05) on the flow behavior index, while their interaction effect was found to be not significant (p>0.05). Conversely, at sample temperature between 50°C to 80°C, the fat content of the cream exhibited a significant (p<0.05) effect on the flow behavior index, while the heat treatment applied to the cream and the interaction effect were not significant (p>0.05). These data are useful to dairy equipment designer for selection of proper sizing of equipment.
Teaching Factory, Entrepreneurship Education and Entrepreneurial Interest: Moderating Effect of Product Innovation
Authors: Nugroho Irvan Agung , Handayani Puji , Kusdiyanti Henny
Published: April 2024

Aims: This study aims to examine the relationship between Teaching Factory and Entrepreneurship Education and the impact of product innovation as a moderating variable on entrepreneurial interest.

Study Design: This study uses a quantitative research design.

Place and Duration of Study: The study population involved all students of Grades XI and XII of State Vocational High School in Banyuwangi Regency with the Teaching Factory learning system. This study used a sample of 250 students selected through a purposive sampling approach.

Methodology: The research instrument used in this study is a questionnaire or survey using a Likert measuring scale, namely an interval scale of 1-5, strongly disagree, disagree, neutral, agree and strongly agree. Data analysis in this study used the Partial Least Squares (PLS) technique to analyze data and apply with PLS4.

Results: All variables are valid and reliable, and there is no multicollinearity in the model. The results concluded that there is a positive relationship between Teaching Factory, Entrepreneurship Education, Product Innovation, and Entrepreneurial Interest.

Conclusion: Teaching Factory and Entrepreneurship Education can be effective instruments in fostering entrepreneurial interest among vocational students and can be used as a foundation for developing similar programs in various educational contexts. dan wilayah.
Effect of Pre- and Post-emergence Herbicide on Weed Growth and Productivity of Summer Mungbean (Vigna radiata)
Authors: Singh Ankit , Singh Alok Kumar , Anshuman Kumar , Singh Amod Kumar , Yadav Sandeep , Solanki Kavita , Srivastav Susheel Kumar , Singh R.D. , Mishra Preyashi , Gupta Sumit , Simmi . , Singh Sakshi
Published: April 2024

The current study aimed to investigate at the Agronomy farm (Faridpur) K.N.I.P.S.S Sultanpur, Uttar Pradesh during kharif 2022-2023. The research was conducted in randomized complete block design (RCBD) with 8 treatments, viz. weedy check, one hand weeding at 15 DAS, hand weeding at 15 and 30 DAS, pendimethalin @ 0.75 kg a.i./ha as pre-emergence (W3), quizalofop-ethyl @ 60 g /ha (20 DAS), Imazethapyr @ 60 g /ha (20 DAS), pendimethalin (PE) fb imazathapyr (20 DAS), pendimethalin (PE) fb quizalofop ethyl (20 DAS). Among all the treatments, growth and yield attributes such as pods count/plant (38.17), seeds count pod-1 (8.66) and yield (12.89 q/ha) were obtained highest with hand weeding at 15 and 30 DAS. Furthermore, the concurrent use of pre- and post-emergence herbicides, demonstrated by combinations like pendimethalin (PE) followed by imazathapyr at 20 DAS and pendimethalin (PE) followed by quizalofop ethyl at 20 DAS, yielded outcomes similar to those achieved through manual weeding.
Determining Adaptability of Potato Genotypes in Mount Elgon Region of Uganda
Authors: L.W Kwaka, , B Chemayek, , A Wasukira, , L Owere, , M Parka, , G Tusiime,
Published: April 2024

Potato (Solanum tuberosum L.)  in Uganda is mainly produced in the highland areas of Kabale and Kisoro in south western and Bugisu and Sebei areas on the slopes of Mt. Elgon in the eastern part of the country. However, the yields have continuously reduced due to lack of suitable high yielding and disease resistant varieties. The purpose of this study was to identify high yielding disease resistant potato genotypes adapted to Mt. Elgon region. Eight CIP potato clones were evaluated alongside ten commonly grown Ugandan varieties in RCBD for two seasons at Buginyanya station, Bulambuli District. Results showed significant differences (P<0.05) in tuber size, tuber uniformity, marketable tuber yield and the total tuber yield among genotypes. Potato clones 392797.22 and 398208.29 produced significantly (P<0.001) higher tuber yield 44.8 t/ha and 39 t/ha respectively compared to the local check Cruza with 34.5 t/ha. rAUDPC for LB showed significant differences (P<0.001) among genotypes in both seasons. The most resistant genotypes were Kinigi and clone 399985.39 with rAUDPC of 0.0135 and 0.025 respectively whereas Bumbamagara (0.413) and 396036.201 (0.392) were the most susceptible. 396036.201(0.051) and Kinigi were the most resistant genotypes for bacterial wilt while Shangi (0.66) and Cruza (0.46) were the most susceptible to BW. Generally, genotypes 392797.22 and 398208.29 were the highest yielding and disease resistant hence recommended for release as commercial varieties.
Role of Nanotrace Element in Prostate Cancer an Update
Authors: Jenifer, S.E. Nancy , Rainy, J.W Evelyn , Velmurugan Janaki
Published: April 2024

Recently, nanomedicine has had a great impact on drug discovery and made the way for the drug delivery system for therapeutic utility. There are many nanoscale products increasing in the research field and in the medical sector. Nanoparticle modified drugs are being developed and brought into the market for the treatment of cancer. The nanoparticle drug carrier can improve the stability of the drug by decreasing the cancerous cell and involving the drug at disease site. Essential trace elements are mostly important for the physiological and biochemical aspects in the human system. Nowadays nanotrace elements are used for the treatment of prostate cancer. In this review the venture and exploration of application of nanomedicine and the use of nanoparticles  with essential trace elements will give a wide range of benefits for the treatment for prostate  cancer.
Resource use Efficiency in Carnation Production under Polyhouse Conditions in Himachal Pradesh, India
Authors: Nikhil . , Bala Brij , Faruk Mohd , Younis Mohd , Namgyal Deldan , Angchuk Sonam , Palmo Tsultim , Abass Mohd
Published: April 2024

Floral expressions often capture the depth of emotions and sentiments that surpass the capabilities of verbal communication. The practice of flower farming within polyhouse conditions has emerged as a burgeoning segment within the agricultural domain, offering substantial revenue opportunities. This is particularly relevant in terrains characterized by hilly topographies, such as Himachal Pradesh, where agricultural land is scarce, with an average of 0.12 hectares of cultivable land and 0.02 hectares of irrigated land per capita. Such limitations necessitate an agricultural paradigm focused on maximizing returns per unit of area, labor, and capital investment. The research undertook an analytical journey in the Bilaspur district of Himachal Pradesh to scrutinize the efficiency of resource utilization in the cultivation of carnations under polyhouse conditions. Engaging a cohort of 60 polyhouse-utilizing farmers, selected through proportional allocation across two blocks of the district, the study unveiled that the utilization efficiencies, as measured by the marginal value product (MVP) to price ratios, were highest for manure (5.78), followed by pesticides (3.55), and labor (2.04), each exceeding the unity threshold. This indicates that augmenting the input of these resources could potentially amplify returns.
Dioxirane Oxidations of Compounds other than Alkenes
Authors: Adam Waldemar , Zhao Cong‐Gui , Jakka Kavitha
Published: February 2008

Epoxidations, heteroatom oxidations, and Y‐H insertions constitute the best investigated oxidations by dioxiranes. This article concerns epoxidation of the double bonds in the cumulenes, such as allenes, acetylenes, and arenes; the oxidation of heteroatom functionalities, mainly lone pairs on sulfur, on nitrogen, and on oxygen as the deoxygenation ofN‐oxides; the oxidation of C = Y functionalities, Y‐H insertions such as in C‐H alkanes, and Si‐H silanes; and the oxidation of organometallic substrates including metal and ligand‐sphere oxidation.
Organ preservation in rectal cancer
Authors: Penninckx F
Published: February 2008

Often possible - but is it safe?
Mechanisms of apoptosis resistance and treatment strategies to overcome them in hormone‐refractory prostate cancer
Authors: Uzzo Robert G. , Haas Naomi B. , Crispen Paul L. , Kolenko Vladimir M.
Published: February 2008

New therapeutic strategies are needed to improve treatment outcomes in men with hormone‐refractory prostate cancer. A better understanding of the molecular mechanisms of cell death in response to therapeutic strategies will help avoid ineffective treatment regimens and provide a molecular basis for new therapeutic modalities targeting apoptosis‐resistant forms of prostate cancer. In this review, the authors focused on the established aberrations of apoptosis in hormone‐refractory prostate cancer, and they have described novel treatment strategies to overcome apoptosis resistance. Cancer 2008. © 2008 American Cancer Society.
Zweischalige Außenwände aus Kalksandsteinmauerwerk
Authors: Prepens Manfred
Published: February 2008

Zweischalige Außenwände bieten hohen Wärme‐ und Witterungsschutz. Die Verblendschale wird im Allgemeinen als Sichtmauerwerk erstellt und ist für die Gestaltung der Gebäude von großer Bedeutung (Bilder 1 und 2).

Passivhausgeeignete Außenwände mit U ≈ 0,15 W/(m2K) lassen sich sehr gut in zweischaliger Bauweise realisieren. Dies ist sowohl mit erhöhten Schalenabständen (nach allgemeiner bauaufsichtlicher Zulassung: bis zu 200 mm zulässig) und/oder durch Einsatz optimierter Wärmedämmstoffe (z. B. Phenolharzhartschaum mit Wärmeleitfähigkeit 0,022 W/(mK)) möglich.

Bei der Ausführung von hochwärmedämmenden zweischaligen Außenwänden ist besonders auf die Minimierung von Wärmebrücken zu achten. Dabei sind vor allem bei den Anschlussdetails Sockel, Fenster, Geschossdecke und Dach sorgfältig zu planen. In der Praxis bewährte Details sind der Detailsammlung Kalksandstein und dem Wärmebrückenkatalog Kalksandstein zu entnehmen.

Als Sperrschicht für die Abdichtung des Fußpunktes der Verblendschalen sind die in DIN 18195 genannten Bitumen‐ oder Kunststoffbahnen zu verwenden. Die Eignung dünnerer Bahnen ist durch ein bauaufsichtliches Prüfungszeugnis für den jeweiligen Anwendungsbereich nachzuweisen und sollte vertraglich vereinbart werden.
A Novel β‐Amino Acid in Cytotoxic Peptides from the Cyanobacterium Tychonema sp.
Authors: Mehner Christian , Müller Daniela , Krick Anja , Kehraus Stefan , Löser Reik , Gütschow Michael , Maier Armin , Fiebig Heinz‐Herbert , Brun Reto , König Gabriele M.
Published: February 2008

The cyclic dodecapeptides tychonamide A (1) and B (2) isolated from the methanolic extract of the cyanobacterium Tychonema sp. contain the novel β‐amino acid 3‐amino‐2,5,7‐trihydroxy‐8‐phenyloctanoic acid (Atpoa). Compounds 1 and 2 have cytotoxic activity towards cancer cell linesin a monolayer assay with mean IC50 values of 0.9 and 3.3 μg mL–1, respectively. Compound 2 was shown to be active against tumor cell suspensions derived fromsolid tumor xenografts in a clonogenic assay (mean IC50 2.4 μg mL–1). Additionally, antiprotozoal activity was observed (Trypanosoma b. rhodesiense, IC50 0.1 μg mL–1) for compound 1. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Bivariate combined linkage and association mapping of quantitative trait loci
Authors: Jung Jeesun , Zhong Ming , Liu Lian , Fan Ruzong
Published: February 2008

In this paper, bivariate/multivariate variance component models are proposed for high‐resolution combined linkage and association mapping of quantitative trait loci (QTL), based on combinations of pedigree and population data. Suppose that a quantitative trait locus is located in a chromosome region that exerts pleiotropic effects on multiple quantitative traits. In the region, multiple markers such as single nucleotide polymorphisms are typed. Two regression models, “genotype effect model” and “additive effect model”, are proposed to model the association between the markers and the trait locus. The linkage information, i.e., recombination fractions between the QTL and the markers, is modeled in the variance and covariance matrix. By analytical formulae, we show that the “genotype effect model” can be used to model the additive and dominant effects simultaneously; the “additive effect model” only takes care of additive effect. Based on the two models, F‐test statistics are proposed to test association between the QTL and markers. By analytical power analysis, we show that bivariate models can be more powerful than univariate models. For moderate‐sized samples, the proposed models lead to correct type I error rates; and so the models are reasonably robust. As a practical example, the method is applied to analyze the genetic inheritance of rheumatoid arthritis for the data of The North American Rheumatoid Arthritis Consortium, Problem 2, Genetic Analysis Workshop 15, which confirms the advantage of the proposed bivariate models. Genet. Epidemiol. 2008. © 2008 Wiley‐Liss, Inc.
Separation of crystal violet dyes and its application to pen ink analysis using CZE and MEKC methods
Authors: Shih Chun‐Min , Liu Ju‐Tsung , Chen Bo‐Hong , Lin Cheng‐Huang
Published: February 2008

A crystal violet (CV) standard was irradiated under a Hg–Cd lamp for different exposure times to obtain various N‐demethylation products. CZE effectively separated the photodegradation products based on molecular weight differences. In contrast, micellar EKC (MEKC), using SDS as the surfactant, was ineffective because the binding constants of the demethylation products and SDS were too close for separation. Nevertheless, MEKC analysis of ink has applications in forensic science because MEKC separated neutral components in the inks. Thus, MEKC can be used to obtain an ink “fingerprint” since each ink is unique depending on the location and time it was made. In contrast, CZE is useful for dating inks because CV is the primary ink dye and it photodegrades slowly.
Sensitivity enhancement for the analysis of naproxen in tap water by solid‐phase extraction coupled in‐line to capillary electrophoresis
Authors: Macià Alba , Borrull Francesc , Calull Marta , Benavente Fernando , Hernández Elena , Sanz‐Nebot Victòria , Barbosa José , Aguilar Carme
Published: February 2008

SPE coupled in‐line to CE, as the strategy to enhance the concentration sensitivity in CE, has been used to enrich naproxen in tap water samples. In this study, a microcartridge containing an octadecyl silica (C18) sorbent was placed near the inlet within the separation capillary column. The optimum conditions were obtained when naproxen in an acidic aqueous solution (pH 3.5) was loaded into the capillary at 930 mbar for 30 min, and 20 mM ammonium acetate in methanol/water (70:30 v/v) was used as both an elution solution and a separation BGE. Under these conditions, the sensitivity was enhanced 1820‐fold with respect to normal hydrodynamic injection, and the LOD achieved was 0.2 μg/L. To show the capability of the in‐line SPE‐CE method, tap water samples were analysed after a pretreatment consisting in an off‐line C18‐SPE procedure. The recovery of this procedure was higher than 80%. Under these conditions, naproxen could be detected at a concentration of 10 ng/L; so the potential of the procedure for the sensitive analysis of this type of drugs in water samples was demonstrated. Afterwards, these results were compared with those previously obtained for naproxen in water samples using different sample stacking techniques.
Macromol. Mater. Eng. 2/2008
Authors: Almasri Atheer , Ounaies Zoubeida , Kim Yeon Seok , Grunlan Jaime
Published: February 2008

Cover: The picture illustrates that the addition of dual wall carbon nanotubes (DWNTs) to PVDF leads to stable solutions, which results in nanocomposite films with good dispersion, and improved mechanical, electrical, dielectric and electromechanical properties as compared to the pure PVDF. These property enhancements may open the way to the development of improved piezoelectric materials for sensors and actuators. Further details can be found in the article by A. Almasri, Z. Ounaies,* Y. S. Kim, and J. Grunlan on page 123.
O‐glycosylation of FoxO1 increases its transcriptional activity towards the glucose 6‐phosphatase gene
Authors: Kuo MeiShiue , Zilberfarb Vladimir , Gangneux Nicolas , Christeff Névéna , Issad Tarik
Published: February 2008

Mono‐O‐glycosylations post‐translationally regulate the activity of nucleocytoplasmic proteins. We showed that glucosamine and an inhibitor of deglycosylation (PUGNAc) induced O‐glycosylation of FoxO1, resulting in increased expression of a glucose‐6‐phosphatase reporter gene. This effect was independent of FoxO1 re‐localisation, since it was also observed with constitutively nuclear FoxO1‐AAA mutant. Moreover, in HepG2 cells, glucosamine and PUGNAc have a synergistic effect on the glucose‐6‐phosphatase reporter gene, and this effect was inhibited by FoxO1 siRNAs. Since glucose‐6‐phosphatase plays a key role in hepatic glucose production, our observation may be of importance with regard to glucotoxicity associated with chronic hyperglycaemia in diabetes.
Spawning aggregations and mass movements in subtidalOnchidoris bilamellata(Mollusca: Opisthobranchia)
Authors: Claverie Thomas , Kamenos Nicholas A.
Published: February 2008

Little is known about spawning aggregations in subtidal populations of the nudibranchOnchidoris bilamellata. We provide photographic evidence of the spawning aggregations and associated spawning migrations or mass movements whose occurrence was debated.
Diet of Tetrapturus belone (Istiophoridae) in the central Mediterranean Sea
Authors: Castriota Luca , Finoia Maria Grazia , Campagnuolo Silvana , Romeo Teresa , Potoschi Antonio , Andaloro Franco
Published: February 2008

The stomach contents of 69 Mediterranean spearfish Tetrapturus belone collected in the Strait of Messina, central Mediterranean Sea were examined. Of the total specimens, caught by harpoon, only three stomachs were empty. Their diet consisted mainly of pelagic fish and cephalopods. The most important piscine prey belonged to the families of Belonidae, Clupeidae and Scomberesocidae. Cephalopods were mainly represented by Tremoctopus violaceus in terms of per cent weight and by Illex coindetii in terms of per cent frequency of occurrence. Tetrapturus belone is an active predator on epipelagic fast-moving prey and school-forming species. Its ecological role is similar to that of other large pelagic species which share the same environment.
New species ofMunidopsis(Decapoda: Anomura: Galatheidae) from hydrothermal vent areas of Indian and Pacific Oceans
Authors: Cubelio Sherine Sonia , Tsuchida Shinji , Watanabe Seiichi
Published: February 2008

Two new species ofMunidopsisfrom the hydrothermal vent area, Kairei Field, Central Indian Ridge in the Indian Ocean and Forecast Vent Field, Mariana Back Arc Basin in the west Pacific are described and illustrated. Their affinities to closely related species are discussed. The number ofMunidopsisspecies associated to hydrothermal vents in the world oceans has increased to 16. The habitat of new species is briefly described and the pattern of abundance of vent associatedMunidopsisis briefly discussed.
Description of the male ofUpogebia miyakeifrom Ryukyu Islands, Japan (Decapoda: Thalassinidea: Upogebiidae)
Authors: Hirano Yuriko , Saigusa Masayuki
Published: February 2008

The small upogebiid shrimp,Upogebia miyakei, was originally described from a female collected from Ishigaki-jima Island, Ryukyu Islands, southern Japan. However, no male specimen has been reported since the discovery of the holotype. During surveys at Iriomote-jima Island and its type locality, both females and males ofU. miyakeiwere collected from the intertidal zone. Based on this material a full description of the male is given, and comparison with the female reveals the sexual dimorphic characteristics. The palm of the first pereiopod of male specimens is about 1.5 times wider than that of females. In male specimens, one or two spines are present on the dorsal margin of the palm of the first pereiopod, while three to six sharp spines are found on female specimens. This species is compared here withUpogebia lincolnifrom Java, Indonesia.
Feeding ecology of monkfish Lophius gastrophysus in the south-western Atlantic Ocean
Authors: Valentim M.F.M. , Caramaschi E.P. , Vianna M.
Published: February 2008

The diet of the monkfish Lophius gastrophysus is described based on the analysis of stomach contents, for the south-western Atlantic from samples landed in the fishing port of Niteroi, Rio de Janeiro state, Brazil, from April 2004 to March 2006. Feeding intensity, measured as the presence or absence of contents in stomachs, and differences in the items' composition were analysed by sex, size-class and season. High feeding intensity predominated for females >32 cm and for males <31 cm. There was no seasonal pattern in the occurrence of full or empty stomachs. The most important category in the diet was fish with 25 identified species. Dactylopterus volitans showed the highest alimentary index value, mainly because of the feeding of juvenile monkfish. The second most important category was Mollusca, represented mainly by squid. No relationships between predator- and prey-lengths and weights were observed; but there was a tendency to consume light and small prey independently of the size of the monkfish.
Measurements of eddy correlation oxygen fluxes in shallow freshwaters: Towards routine applications and analysis
Authors: McGinnis Daniel F. , Berg Peter , Brand Andreas , Lorrai Claudia , Edmonds Theresa J. , Wüest Alfred
Published: February 2008

Benthic fluxes of dissolved oxygen are measured in a shallow reservoir using the eddy correlation technique. Flux variations depict the diurnal production‐consumption cycle, with daytime oxygen release following the solar radiation trend. The average nighttime uptake of −40 ± 11 mmol m−2 d−1 is in excellent agreement with the rate of −35 ± 3 mmol m−2 d−1 derived from sediment oxygen microprofiles. Separating large‐scale advective and turbulent fluctuations is a crucial and uncertain component of the flux computation and the largest source of error. To compensate for the 2.25 s oxygen sensor response time, the oxygen flux calculations are corrected by only ∼5% using a first‐order spectral enhancement. This work demonstrates that only a slightly faster oxygen sensor would be needed to resolve the entire flux spectrum. The 18 hours of data are the first measurements obtained in a freshwater reservoir that capture the diurnal oxygen production‐consumption cycle.
Ion sources for energy extremes of ion implantation (invited)
Authors: Hershcovitch A. , Johnson B. M. , Batalin V. A. , Kropachev G. N. , Kuibeda R. P. , Kulevoy T. V. , Kolomiets A. A. , Pershin V. I. , Petrenko S. V. , Rudskoy I. , Seleznev D. N. , Bugaev A. S. , Gushenets V. I. , Litovko I. V. , Oks E. M. , Yushkov G. Yu. , Masunov E. S. , Polozov S. M. , Poole H. J , Storozhenko P. A. , Svarovski A. Ya.
Published: February 2008

For the past four years a joint research and development effort designed to develop steady state, intense ion sources has been in progress with the ultimate goal to develop ion sources and techniques that meet the two energy extreme range needs of meV and hundreads of eV ion implanters. This endeavor has already resulted in record steady state output currents of high charge state of antimony and phosphorus ions: P2+ [8.6pmA (particle milliampere)], P3+ (1.9pmA), and P4+ (0.12pmA) and 16.2, 7.6, 3.3, and 2.2pmA of Sb3+Sb4+, Sb5+, and Sb6+ respectively. For low energy ion implantation, our efforts involve molecular ions and a novel plasmaless/gasless deceleration method. To date, 1emA (electrical milliampere) of positive decaborane ions was extracted at 10keV and smaller currents of negative decaborane ions were also extracted. Additionally, boron current fraction of over 70% was extracted from a Bernas-Calutron ion source, which represents a factor of 3.5 improvement over currently employed ion sources.
Investigation of rf power absorption in the plasma of helicon ion source
Authors: Mordyk S. , Alexenko O. , Miroshnichenko V. , Storizhko V. , Stepanov K. , Olshansky V.
Published: February 2008

The simulations of the spatial distribution of rf power absorbed in a helicon ion source reveal a correlation between the depth of penetration of rf power into the plasma and the tilt angle of lines of force of the outer magnetic field. The deeper field penetration and greater power absorption were observed at large tilt angles of the field line to the plasma surface. The evaluations as to the possibility of excitation of helicon waves in compact rf ion sources were performed.
Intense beam production of highly charged heavy ions by the superconducting electron cyclotron resonance ion source SECRAL (invited)
Authors: Zhao H. W. , Sun L. T. , Zhang X. Z. , Guo X. H. , Cao Y. , Lu W. , Zhang Z. M. , Yuan P. , Song M. T. , Zhao H. Y. , Jin T. , Shang Y. , Zhan W. L. , Wei B. W. , Xie D. Z.
Published: February 2008

There has been increasing demand to provide higher beam intensity and high enough beam energy for heavy ion accelerator and some other applications, which has driven electron cyclotron resonance (ECR) ion source to produce higher charge state ions with higher beam intensity. One of development trends for highly charged ECR ion source is to build new generation ECR sources by utilization of superconducting magnet technology. SECRAL (superconducting ECR ion source with advanced design in Lanzhou) was successfully built to produce intense beams of highly charged ion for Heavy Ion Research Facility in Lanzhou (HIRFL). The ion source has been optimized to be operated at 28GHz for its maximum performance. The superconducting magnet confinement configuration of the ion source consists of three axial solenoid coils and six sextupole coils with a cold iron structure as field booster and clamping. An innovative design of SECRAL is that the three axial solenoid coils are located inside of the sextupole bore in order to reduce the interaction forces between the sextupole coils and the solenoid coils. For 28GHz operation, the magnet assembly can produce peak mirror fields on axis of 3.6T at injection, 2.2T at extraction, and a radial sextupole field of 2.0T at plasma chamber wall. During the commissioning phase at 18GHz with a stainless steel chamber, tests with various gases and some metals have been conducted with microwave power less than 3.5kW by two 18GHz rf generators. It demonstrates the performance is very promising. Some record ion beam intensities have been produced, for instance, 810eμA of O7+, 505eμA of Xe20+, 306eμA of Xe27+, and so on. The effect of the magnetic field configuration on the ion source performance has been studied experimentally. SECRAL has been put into operation to provide highly charged ion beams for HIRFL facility since May 2007.
Multiaperture ion beam extraction from gas-dynamic electron cyclotron resonance source of multicharged ions
Authors: Sidorov A. , Dorf M. , Zorin V. , Bokhanov A. , Izotov I. , Razin S. , Skalyga V. , Roßbach J. , Spädtke P. , Balabaev A.
Published: February 2008

Electron cyclotron resonance ion source with quasi-gas-dynamic regime of plasma confinement (ReGIS), constructed at the Institute of Applied Physics, Russia, provides opportunities for extracting intense and high-brightness multicharged ion beams. Despite the short plasma lifetime in a magnetic trap of a ReGIS, the degree of multiple ionization may be significantly enhanced by the increase in power and frequency of the applied microwave radiation. The present work is focused on studying the intense beam quality of this source by the pepper-pot method. A single beamlet emittance measured by the pepper-pot method was found to be ∼70πmmmrad, and the total extracted beam current obtained at 14kV extraction voltage was ∼25mA. The results of the numerical simulations of ion beam extraction are found to be in good agreement with experimental data.
An active-optic x-ray fluorescence analyzer with high energy resolution, large solid angle coverage, and a large tuning range
Authors: Adams Bernhard W. , Attenkofer Klaus
Published: February 2008

A crystal-optic x-ray fluorescence energy analyzer has been designed and tested, which combines the features of electron-volt energy resolution, large solid angle coverage, and tunability over several kilo-electron-volts. The design is based upon the principle of active optics, with ten actuators available to optimally adjust the shape of a silicon crystal used in the Bragg geometry. In most applications the shape is that of a logarithmic spiral for high energy resolution with a spatially nonresolving detector, but a wide range of other shapes is also possible for applications such as imaging or single-shot spectroscopy in a spectral range of the operator’s choosing.
Feasibility of density functional methods to predict dielectric properties of polymers
Authors: Ruuska Henna , Arola Eero , Kannus Kari , Rantala Tapio T. , Valkealahti Seppo
Published: February 2008

Feasibility of density functional theory (DFT) to predict dielectric properties such as polarizability of saturated polymers is investigated. Small saturated molecules, methane and propane, which is a monomer of polypropylene chain, are used in testing the methods. Results for polarizabilities based on several density functionals together with different basis sets are compared and contrasted with each other, with results by Hartree-Fock and second-order Møller-Plesset perturbation theory, as well as experimental data. The generalized gradient approximation PW91 method together with the 6-311++G** basis set is found to be the most suitable method, in terms of sufficient accuracy and computational efficiency, to calculate polarizabilities for large oligomers of polypropylene. The dielectric constant is then determined using the calculated polarizabilities and the Clausius-Mossotti equation. The molecular DFT methods at the PW91∕6-311++G** level together with the Clausius-Mossotti equation give dielectric constants for saturated polymers such as polypropylene in good accordance with the experimental values.
Wetting of mixed OH∕H2O layers on Pt(111)
Authors: Zimbitas Georgina , Gallagher Mark E. , Darling George R. , Hodgson Andrew
Published: February 2008

We describe the effect of growth temperature and OH∕H2O composition on the wetting behavior of Pt(111). Changes to the desorption rate of ice films were measured and correlated to the film morphology using low energy electron diffraction and thermal desorption of chloroform to measure the area of multilayer ice and monolayer OH∕H2O exposed. Thin ice films roughen, forming bare (√39×√39)R16° water monolayer and ice clusters. The size of the clusters depends on growth temperature and determines their kinetic stability, with the desorption rate decreasing when larger clusters are formed by growth at high temperature. Continuous films of more than approximately 50 layers thick stabilize an ordered incommensurate ice film that does not dewet. OH coadsorption pins the first layer into registry with Pt, forming an ordered hexagonal (OH+H2O) structure with all the H atoms involved in hydrogen bonding. Although this layer has a similar honeycomb OHx skeleton to ice Ih, it is unable to reconstruct to match the bulk ice lattice parameter and does not form a stable wetting layer. Water aggregates to expose bare monolayer (OH+H2O), forming bulk ice crystallites whose size depend on preparation temperature. Increasing the proportion of water in the first layer provides free OH groups which stabilize the multilayer. The factors influencing multilayer wetting are discussed using density functional theory calculations to compare water adsorption on top of (OH+H2O) and on simple models for commensurate water structures. We show that both the (OH+H2O) structure and “H-down” water layers are poor proton acceptors, bonding to the first layer being enhanced by the presence of free OH groups. Formation of an ordered ice multilayer requires a water-metal interaction sufficient to wet the surface, but not so strong as to prevent the first layer relaxing to stabilize the interface between the metal and bulk ice.
Effects of Zr, Nb, and Cu substitutions on magnetic properties of melt-spun and hot deformed bulk anisotropic nanocomposite SmCo type magnets
Authors: Huang M. Q. , Turgut Z. , Ma B. M. , Chen Z. M. , Lee D. , Higgins A. , Chen C. H. , Liu S. , Chu S. Y. , Horwath J. C. , Fingers R. T.
Published: February 2008

Structure and magnetic properties of both melt-spun and hot deformed bulk Sm–Co type nanocomposite magnets have been investigated with various metal additions, including Zr, Cu, and Nb. The Zr and Nb additions play important roles in constraining grain growth, resulting in an increase of coercivity Hc. The Cu addition significantly improves the squareness of BH loops as well as the energy product (BH)max. A typical hot deformed bulk anisotropic nanocomposite SmCo type magnet with Mr(hard)∕Mr(easy)∼0.4, Hc∼9kOe and (BH)max of 13.2MGOe was obtained.
The geometric minimum action method for computing minimum energy paths
Authors: Vanden-Eijnden Eric , Heymann Matthias
Published: February 2008

An algorithm is proposed to calculate the minimum energy path (MEP). The algorithm is based on a variational formulation in which the MEP is characterized as the curve minimizing a certain functional. The algorithm performs this minimization using a preconditioned steepest-descent scheme with a reparametrization step to enforce a constraint on the curve parametrization.
Evaluation of mean energy fluxes in thermoacoustic oscillations of a gas in a tube
Authors: Sugimoto N. , Shimizu D. , Kimura Y.
Published: February 2008

In a previous paper [N. Sugimoto and M. Yoshida, Phys. Fluids 19, 074101 (2007)], the marginal condition for the onset of thermoacoustic oscillations of a gas in a tube subjected to the parabolic temperature distribution was derived in the framework of the linear and first-order theory in the boundary-layer thickness. This paper examines the marginal oscillations from a viewpoint of mean energy fluxes averaged over one period of oscillations, aiming at understanding an action of the boundary layer under finite temperature gradient. Using the nonlinear energy equation, formulas for the acoustic energy flux and the convective heat flux (entropy flux times temperature) are derived in the main-flow region and in the boundary layer within the lowest, quadratic order in the pressure amplitude. These fluxes may be evaluated in terms of the linearized solutions and their axial distributions are displayed graphically. The boundary layer occupying nearly half of the side wall near the open end plays an active role to pump energy into the acoustic main-flow region, whereas the other half plays a passive role to dissipate energy. The acoustic energy flux in the main-flow region flows toward the closed end, while the flux in the boundary layer flows down the gradient of the pressure amplitude and toward the open end. The convective heat flux flows only in the boundary layer and directed down the temperature gradient. In the vicinity of the closed end, however, this heat flux flows against the temperature gradient. The heat flux through the side wall comes mostly into the boundary layer but goes out of it near the closed end. Such an Eulerian picture of the flow field is examined from a Lagrangian viewpoint in terms of thermodynamic relations for a gas particle fixed. While the particle in the main-flow region is subjected to the adiabatic change to yield no net power per one period of oscillations, the one in the boundary layer is subjected to a thermodynamic cycle of a prime mover or a heat pump, depending on whether the value of the product of the gradients of the logarithmic temperature and pressure amplitude is beyond a certain value. Discussions are also focused on the mechanisms to maintain the marginal state of oscillations and the efficiency as heat engines.
High strength bulk Fe–Co alloys produced by powder metallurgy
Authors: Turgut Zafer , Huang Meiqing , Horwath John C. , Fingers Richard T.
Published: February 2008

Fe–Co alloys are extensively used in lamination form, but there are certain power generation applications that require Fe–Co rotors in bulk form. Experiencing only a dc magnetic field, these rotors can be as large as 0.5m in diameter, depending on the size of the generator. The forging of such large pieces of Fe–Co has proven to be difficult. The present study investigates powder metallurgy processing of a gas atomized FeCoNbV alloy through hot isostatic pressing (HIP) for manufacturing large size rotors with improved mechanical strength. Gas atomized FeCoNbV alloy powders with and without ball milling were hot isostatic pressed at temperatures between 675 and 850°C at a fixed pressure of 193MPa for up to 6h. Ball milling prior to HIP improved the yield strength. A further improvement in yield strength and in ductility was obtained after a disordering heat treatment at 730°C followed by a rapid quench to room temperature. The optimum HIP and annealing conditions resulted in samples with yield strengths of 870MPa. The compacts exhibited average coercivity values of 6.4Oe and maximum permeability values of 1100.
A preliminary study of spatial resolution enhancement of confocal and triangulation displacement meters using contact mode scanning probes
Authors: Gaitas Angelo
Published: February 2008

This paper presents a method for the spatial resolution enhancement of confocal and triangulation meters using cantilever probes. Integration of a cantilever with existing commercially available meters is substantially eased by the absence of feedback control of the cantilever position. Confocal and triangulation meters are used for a number of applications in research and industrial settings including thickness measurements, topography measurements, step height measurements, flatness measurements, and profile measurements. These instruments provide a vertical (out-of-plane) resolution of a few nanometers. However, they are limited in their spatial resolution to the laser beam diameter, which is typically larger than 2μm and often about 20μm. Using a cantilever probe to make contact with the sample, the lateral resolution of standard commercial instruments can be improved to less than 1μm.
Simultaneous normal and shear measurements of nanoconfined liquids in a fiber-based atomic force microscope
Authors: Matei George , Jeffery Steve , Patil Shivprasad , Khan Shah H. , Pantea Mircea , Pethica John B. , Hoffmann Peter M.
Published: February 2008

We have developed an atomic force microscopy (AFM) technique that can perform simultaneous normal and shear stiffness measurements of nanoconfined liquids with angstrom-range amplitudes. The AFM technique is based on a fiber-interferometric, small-amplitude, off-resonance AFM. This AFM is capable of providing linear quasistatic measurements of the local mechanical properties of confined liquid layers while only minimally disturbing the layers themselves. A detailed analysis of the measurement geometry reveals that shear stiffness measurements are extremely challenging, as even small deviations from perfect orthogonality can lead to data that is very difficult to interpret. We will show ways out of this dilemma and present results that show simultaneous measurement of the shear and normal stiffness of confined liquid layers.
A new microscope optics for laser dark-field illumination applied to high precision two dimensional measurement of specimen displacement
Authors: Noda Naoki , Kamimura Shinji
Published: February 2008

With conventional light microscopy, precision in the measurement of the displacement of a specimen depends on the signal-to-noise ratio when we measure the light intensity of magnified images. This implies that, for the improvement of precision, getting brighter images and reducing background light noise are both inevitably required. For this purpose, we developed a new optics for laser dark-field illumination. For the microscopy, we used a laser beam and a pair of axicons (conical lenses) to get an optimal condition for dark-field observations. The optics was applied to measuring two dimensional microbead displacements with subnanometer precision. The bandwidth of our detection system overall was 10kHz. Over most of this bandwidth, the observed noise level was as small as 0.1nm∕√Hz.
Self-normalized photoacoustic technique for thermal diffusivity measurements of transparent materials
Authors: Balderas-López J. A.
Published: February 2008

A self-normalized photoacoustic methodology for thermal diffusivity measurements of thin foils of transparent materials is presented. The methodology implementation involves attaching a high optically opaque thin film on one of the transparent sample’s surface. The corresponding measurement procedure involves the analysis of the normalized phase, as a function of the modulation frequency, in the thermally thin and thick regimes. Since the purely thermal-diffusion-wave mechanism is assumed then simple experimental criteria, to ascertain that this is the case in the selected modulation frequency range, is also reported. Three different materials were examined using the proposed methodology: cover glass slabs and thin foils of acetate and polyvinylidene difluoride polymers.
Construction of refractive-index profile of Ag+–Na+ ion-exchange channel waveguide by two-dimensional inverse matrix method
Authors: Ma Yun-Feng , Wei Jue , Pei Jin-Hua , Kang Zhi-Hui , Jiang Yun , Gao Jin-Yue
Published: February 2008

The refractive-index profile of ion-exchange channel waveguide is reconstructed by near-field measurement combined with two-dimensional inverse matrix method, which can avoid the problems brought by multimeasurements and iteration smoothing in the process. The method used here has the advantages of convenient operation and accurate results for the characteristics of the asymmetric channel waveguide. It can be also applied to the refractive-index profile measurements of graded index fibers, polarization maintaining fibers, and single-mode planar waveguides.
Analysis of ballistic monolayer and bilayer graphene field-effect transistors
Authors: Ouyang Yijian , Campbell Paul , Guo Jing
Published: February 2008

We examine and compare ballistic performance limits of metal-oxide-semiconductor field-effect transistors with monolayer and bilayer graphene channels. Under low source-drain biases and cryogenic temperatures, the leakage current of the bilayer device is orders of magnitude smaller than that of the monolayer device. The advantage lowers at raised temperatures and source-drain biases. The bilayer device, however, still has qualitatively different and more favorable I-V characteristics. We find the ballistic on-state channel conductance and the minimum channel conductance have distinctly different dependences on the channel length.
Method to distinguish ferroelectric from nonferroelectric origin in case of resistive switching in ferroelectric capacitors
Authors: Kohlstedt H. , Petraru A. , Szot K. , Rüdiger A. , Meuffels P. , Haselier H. , Waser R. , Nagarajan V.
Published: February 2008

We present investigations on the resistive switching effect in SrRuO3∕PbZr0.2Ti0.8O3∕Pt ferroelectric capacitors. Using a conductive atomic force microscope, the out-of-plane piezoelectric response and the capacitive and resistive current were simultaneously measured as a function of applied bias voltage. We observed two independent switching phenomena, one attributed to the ferroelectric switching process and the other to resistive switching.We show that I-V curves alone are not sufficient in ferroelectric materials to clarify the underlying switching mechanism and must be used with sufficient caution.
Strain-mediated magnetoelectric coupling in BaTiO3-Co nanocomposite thin films
Authors: Park Jung H. , Jang Hyun M. , Kim Hyung S. , Park Chan G. , Lee Sang G.
Published: February 2008

The authors present a metal-ceramic type composite film in which Co particles with the mean size of 70nm are uniformly dispersed in an insulating ferroelectric BaTiO3 (BTO) matrix. Transmission electron microscopy images revealed that the Co particle was tightly surrounded with the BTO matrix in atomic scales. The magnetostrictive strain-induced change in the relative dielectric permittivity was demonstrated by observing pronounced magnetodielectric effects under a static bias magnetic field. The present BTO-Co composite thin film also exhibited large dynamic magnetoelectric responses (160–170mV∕cmOe at 50kHz) at room temperature by virtue of a tight bonding between the two constituting piezoelectric and magnetostrictive phases.
Ferromagnetism and magnetodielectric effect in insulating LaBiMn4∕3Co2∕3O6 thin films
Authors: Ranjith R. , Kundu Asish K. , Filippi M. , Kundys B. , Prellier W. , Raveau B. , Laverdière J. , Singh M. P. , Jandl S.
Published: February 2008

High quality epitaxial thin films of LaBiMn4∕3Co2∕3O6 perovskite were fabricated on (001)-oriented SrTiO3 and LaAlO3 substrates by the pulsed laser deposition technique. Magnetization measurements reveal a strong magnetic anisotropy and a ferromagnetic behavior that is in agreement with a superexchange interaction between Mn4+ and Co2+ ions, which are randomly distributed in the B site. A distinct anomaly is observed in the dielectric measurements at 130K corresponding to the onset of the magnetic ordering, suggesting a coupling. Above this temperature, the extrinsic Maxwell–Wagner effect is dominating. These results are explained using the Raman spectroscopic studies indicating a weak spin-lattice interaction around this magnetic transition.
Hexahedral nanocementites catalyzing the growth of carbon nanohelices
Authors: Xia J. H. , Jiang X. , Jia C. L. , Dong C.
Published: February 2008

The formation mechanism of carbon nanohelices grown on iron needles by microwave plasma assisted chemical vapor deposition is studied by means of transmission electron microscopy and scanning electron microscopy. The catalyst assisting the helix formation is identified to be the single crystalline cementite (Fe3C) particle at the tip of each carbon nanohelix. The Fe3C particles show the general morphology of a hexahedron with six (different) crystallographic planes as the surface planes. The different catalytic effect of different crystallographic surface planes produces an anisotropic growth on the front surface of the carbon nanostructure, which results in a rotation of the cementite particles. The rotating particles catalyze the growth of the carbon nanostructure in a helical way.