bluuebunny/crossref_metadata_2025 huggingface dataset:
The Mechanical Properties and Fracture Characteristics of AlN/Ti Laminated Composites
Authors: Zhang Tao , Li Wen Zhao , Jin Hai Yun , Qiao Guan Jun , Jin Zhi Hao
Published: July 2010

The AlN/Ti laminated composites were fabrication by plasma activated sintering. In the composites, the AlN layers were matrix layers and the Ti layers were as the toughening layers. The microstructure and mechanical properties were studied. XRD and SEM results showed that a new phase (TiN, Al5Ti2) in the layer interface was generated by reaction of AlN and Ti. The AlN/Ti interface bonding was strengthened by existing of the new phase, plastic deformation and bridging of ductile Ti phase. The crack propagation path would be extended by the flexuous pattern. Therefore, the fracture toughness of composites was improved obviously comparing with the monolithic AlN and the bending strength decreased a little.
Effect of Processing Condition on the Microstructure and Mechanical Properties of Ti3SiC2/SiC Composites
Authors: Yin Hong Feng , Lu Lin Lin
Published: July 2010

Ti3SiC2/SiC composites were fabricated by reactive hot pressing method. Effect of processing condition on the microstructure and mechanical properties of the composites were investigated. The results showed that: (1) Hot-pressing temperature influenced the phase constituent of Ti3SiC2/SiC composites. The flexural strength and fracture toughness of composites increased with hot pressing temperature. (2) The flexural strength and fracture toughness of composites increased when the content of SiC was increased. When the SiC content was 30wt% the flexural strength and fracture toughness of Ti3SiC2/SiC composite were 371MPa and 6.9MPa•m1/2 respectively. However, when the content of SiC reached 50wt%, the flexural strength and fracture toughness of composites decreased due to high porosity in the composites. (3) The flexural strength and fracture toughness of composites increased with the particle size of SiC added in composites. (4) Ti3SiC2/SiC composites were non-brittle at room temperature.
Effects of Thickness on Thermal and Mechanical Properties of Air-Plasma Sprayed Thermal Barrier Coatings
Authors: Lee Sang Yeop , Kwon Jae Young , Kang Tae Woong , Jung Yeon Gil , Paik Ung Yu
Published: July 2010

Thermal barrier coating systems (TBCs) prepared by an air-plasma spray (APS) have been used to protect metallic components of gas turbines because of its economic advantage. To enhance the energy efficiency of gas turbine systems, the operating temperature is increased to over 1300 °C, which requires a new material with low thermal conductivity and an increase of TBC thickness. In this study we have focused the microstructure related to the thickness of TBC and their thermal properties, with specific attention to defect species as well as to its morphology with the thermal exposure time. Resintering of TBC happens during thermal exposure in a high temperature, resulting in the less strain tolerance and the higher thermal conductivity. In order to investigate the thermal properties of TBC related to the microstructural evolution, TBCs with different thicknesses of 200 µm, 400 µm, 600 µm, and 2000 µm were deposited on a flat graphite by the APS. The thermal exposure tests were conducted in different dwell time till 800h at 1100 °C. The thermal diffusivity is significantly increased after thermal exposures, depending on the thermal exposure time. Microstructural analysis clearly shows that the variation of thermal diffusivity is ascribed to the coalescence of small cracks and the resintering effect. The hardness values of TBCs are also increased as well. The relationship between mechanical properties and TBC thickness is discussed, including the effect of thickness on thermal properties.
Effects of Different Solid Lubricants on Mechanical and Tribological Properties of Al2O3/ZrO2 Nanocomposites
Authors: Kim Seung Ho , Cho Sung Hun , Hannula Simo Pekka , Lee Soo Wohn
Published: July 2010

Solid lubricants were suited for the applications of high temperature parts. Recently, researches for self-lubricating ceramic matrix composites using solid lubricants, such as MoS2, WS2, h-BN, and graphite etc., became active. This work is to use the spark plasma sintering (SPS) technique in order to make self-lubricating Al2O3/15wt% ZrO2 nanocomposites with higher mechanical properties. To optimize the self-lubricating Al2O3/15wt% ZrO2 nanocomposite systems were added with different solid lubricants (CaF2, BaF2, MoS2, WS2, h-BN, and graphite). The coefficient of friction of CaF2, h-BN and graphite added composites in steady-state at room temperature are below 0.3.
Front End Bending in Plate Rolling Influenced by Asymmetrical Entrance Angle
Authors: Pang Yu Hua , Hu Yang Lei , Sun Qi , Liu Chang Rui , Yu Hai Feng , Lu Bin , Zhang Mei Ming
Published: July 2010

Material rolled in heavy plate mills and roughing stands often bends upwards or downwards. This phenomenon can lead to poor shape, profile and quality of the product, as well as lower productivity. This paper focuses on the well- known bending due to the related asymmetrical entrance angle between the rolling stock and work roll which can easily cause asymmetrical shape factor in deformation zone. A model for calculating curvature quickly is deduced based on the condition of asymmetrical entrance angle. Results show that the front end bending can occur easily due to the asymmetrical entrance angle. Moreover, the bending inclination of large reduction, large radius of roll and thin rolling stock is greater than that of the reverse; the bending inclination of the entrance thickness of rolling stock is greater than that of the reduction, and the bending inclination of the reduction is greater than that of the radius of roll.
Study on the Microstructure of Au/CdZnTe Interface by HRTEM
Authors: Jie Sun , Fu Li , Ming Nie Zhong
Published: July 2010

As a new type of detector material, the CdZnTe (CZT) crystal has the advantages such as a wide energy gap, a large average atomic number, the strong ability to stop X- ray and high resistivity. The CZT is not only the best epitaxial substrate to the growth process of infrared detector material—HgCdTe, but also can be widely used in the detector production of X-ray fluorescence analysis, nuclear waste monitoring, airport and port security testing, industrial detection, medical diagnosis, astrophysics research, etc. So it has very broad prospects. Compared with the traditional NaI detector, the CZT detector has a better energy resolution. Compared with Si and Ge detector, it can work at room temperature. So it absorbed great attention in recent years. The structure of the interface between the metal electrode and CZT has great effect on the performance of detector. Au electrode film was prepared on high resistance CZT single crystal by using vacuum evaporation technology in this research. The interface of Au/CZT was investigated by high resolution transmission electron microscope (HRTEM). The results showed that there existed a disordered layer with the thickness of 5-10nm in the interface between the Au electrode and CZT wafer which was only mechanical polished (as opposed to polished and etched) in our present experimental condition. That could be approved as an amorphous layer through diffraction pattern. On the other hand, the interface was flat, smooth and no amorphous layer on which CZT wafer was polished and etched.
Preparation and Dielectric Properties of Alumina Filled Epoxy Nano-Composite
Authors: Shi Hui Cheng , Gao Nai Kui , Jin Hai Yun , Wang Chuan Bin
Published: July 2010

The reported enhancement in dielectric properties obtained for polymer nano-composite seemed to be very encouraging. To further understand the dielectric behavior of epoxy nano-composite, aluminum oxide (Al2O3) nano-particles were incorporated into bisphenol A epoxy resin, and the dependence of nano-particle content and the dielectric properties was investigated in this study. Results showed that, when nano-particle contents was no more than 10phr, relative permittivity (εr) decreased to be lower than that of monolithic epoxy, and the minimum value appeared in 4phr nano-particle filled composite. The minimum value of tan delta (tanδ) appeared in 6phr nano-particle filled composite. DC volume resistivity (ρv) increased due to the introduction of nano-particles when the filler content is very small (about 2phr).
Analysis on Microstructure and Mechanical Properties of Pine Laminated Veneer Lumber
Authors: Xue Bing , Hu Ying Cheng , Cheng Fang Chao , Zhang Li
Published: July 2010

In this paper, four different nondestructive testing (NDT) methods and the static bending test were conducted on the pine (Pinus sylvestris L. Var. mongolica Litven.) laminated veneer lumber (LVL). The NDT methods included the longitudinal transmission method, longitudinal vibration method, in-plane and out-plane flexural vibration method. The effects of the compression ratio on the Young’s modulus and bending strength (MOR) of LVL were investigated. There were four compression ratios for different ply numbers of LVL, 8.1% for eight-ply samples, 18.3% for nine-ply samples, 26.5% for ten-ply samples, 33.1% for eleven-ply samples, respectively. The microscopic structure of the LVL was analyzed with a scanning electron microscope (SEM). The results showed that the microstructure of LVL changed greatly between different compression ratios. And the dynamic Young’s modulus and static bending (MOE) and bending strength (MOR) were greatly increased when the compression ratio increased form 18.3% to 26.5%.
A New Preparation Method of Visible Light Responsive Titanium Dioxide Photocatalytic Films by Ultraviolet Irradiation
Authors: Nishizawa Kaori , Watanabe Eiji , Maeda Masaki
Published: July 2010

Titanium dioxide sol solution was prepared using titanium tetra-isopropoxide, urea, 2-methoxyethanol. After that, ultraviolet light was irradiated to the sol solution, then, H2O was added to the solution. The prepared sol solution was dip-coated onto fused silica plates. The as-prepared films were dried at 100 °C and then annealed at 650 °C. The annealed films were anatase type titanium dioxides. Visible light absorption by the films was observed in wavelengths longer than 380 nm. Also, photodegradation of methylene blue by visible light irradiation was accelerated in the presence of the films prepared by these methods.
Sol-Gel Preparation of Bi2InTaO7 and its Photocatalytic Behavior for Organic Compounds Degradation
Authors: Torres-Martínez Leticia M. , Juárez-Ramírez Isaías , Ramos-Garza Juan S. , Vázquez-Acosta Francisco , Lee Soo Wohn
Published: July 2010

In this work it was carried out the synthesis of Bi2InTaO7 pyrochlore-type structure compound by the sol-gel method. By X-Ray powder diffraction the sol-gel compound calcined at 600°C showed the pyrochlore-type structure phase and by scanning electron microscopy its morphology revealed the presence of particles with size lower than 1 micron. Its chemical elemental composition was determined by EDS analysis. Results of SBET area and Eg values of this compound suggested higher properties than those obtained by the compound prepared by solid state reaction. Bi2InTaO7 sol-gel was used as active photocatalyst on the degradation reaction of organic compounds such as Alizarin Red S, and Red and Green Tide, under UV-light. Half time life results showed that Bi2InTaO7 sol-gel compound could be a good candidate for the degradation of organic compounds because after few minutes showed high efficiency on the degradation reaction of Alizarin Red S (t1/2 = 30 min), and Green Tide inactivation (t1/2 = 17 min).
Photoinduced Absorption in P3HT/PCBM Bulk Heterostructures
Authors: Kinoshita Keita , Kobayashi Takashi , Nagase Takashi , Naito Hiroyoshi
Published: July 2010

We investigate the dynamics of charged states (polarons) in bulk heterostructures of polythiophene and fullerene derivatives by means of photoinduced absorption spectroscopy, and is compared them with those in pristine polythiophene thin films. Polaron lifetimes in the bulk heterostructure and in polythiophene thin films at 6 K exceed 140 and 17 μs, respectively. The difference in lifetime indicates that charged states are better stabilized by the addition of the fullerene derivative. We also find that the dynamics of intrachain singlet excitons, which are not observed in the bulk heterostructure, are different from that of polarons in polythiophene thin films.
Effect of Matrix on Phase Formation of Nanometer TiO2 Film
Authors: Deng Zhen Yan , Zhu Li Li , Gai Wei Zhuo , Ferreira José Maria F.
Published: July 2010

TiO2 films were prepared by infiltrating a titanium (IV) butoxide solution to the porous structures of glass and rutile TiO2, respectively, then dried and calcined at a moderate temperature of 550°C. Well-characterized porous nanometer TiO2 films were formed. Nanometer TiO2 film on glass matrix has an anatase phase, while that on rutile TiO2 has a rutile phase. These indicate that the phase formation of nanometer TiO2 could be tailored by the different matrices.
Lead Based Multi-Alloy Applied to Anode of Zinc Electrowinning
Authors: Zhu Jun , Li Xin , Liu Man Bo , Zhai Ying
Published: July 2010

Alloy anode materials play an important role in zinc electrowinning process. Many kind of alloys can be used as anode materials, the selection of anode alloy directly influence the quality and cost of zinc electrowinning. Pb-Ag alloy anode material has been used generally in zinc electrowinning, however, it is proved the existence of many problems in practice. An important subject that new lead based multi-alloy applied to zinc electrowinning has been confirmed. Contrast testing study on the performance between Pb-Ag alloy anode plate and lead based multi-alloy anode plate was carried out on the basis of the research status, such as the output of precipitated zinc, the quality of electrolytic zinc, power consumption and anode life. It was found that when the technology of alloy-making had a breakthrough, the Pb-Ag alloy anode could be replaced by lead based multi-alloy anode under the condition that electrowinning technology was adapted, and the production costs could also be reduced.
Synthesis of Spherical Carbon Nanoparticles and their EDLC Properties
Authors: Zheng Guo Bin , Sano Hideaki , Uchiyama Yasuo
Published: July 2010

Spherical carbon nanoparticles were synthesized by sol-gel polymerization of resorcinol and formaldehyde in the presence of CTAB(cetyltrimethylammonium bromide) and subsequent carbonization at 900°C. It is found that the amount of CTAB, water and catalyst showed a significant impact on the morphology and size of carbon nanoparticles. According to the BET surface area and capacitance, the nanoparticles were divided into two groups. The carbon nanoparticles with surface area of 725-758 m2/g showed capacitance between 120-140 F/g, while those with surface area of 596-649 m2/g showed capacitance only 60-80 F/g. Difference in the pore size of 1.5 nm to 3.0 nm probably contributed to the difference of capacitance.
B and T Lymphocyte Attenuator Suppresses IL-21 Production from Follicular Th Cells and Subsequent Humoral Immune Responses
Authors: Kashiwakuma Daisuke , Suto Akira , Hiramatsu Yukiko , Ikeda Kei , Takatori Hiroaki , Suzuki Kotaro , Kagami Shin-ichiro , Hirose Koichi , Watanabe Norihiko , Iwamoto Itsuo , Nakajima Hiroshi
Published: July 2010

We recently showed that mice lacking B and T lymphocyte attenuator (BTLA), a third inhibitory coreceptor expressed on B cells and T cells, exhibit an increased Ag-specific IgG response and gradually develop hyper-γ–globulinemia and autoantibody production. Recent studies revealed that follicular Th (Tfh) cells, which are non-Th1, non-Th2 effector T cells that express CXCR5 and provide help for B cells to produce Ig, also express BTLA. However, the role of BTLA in Tfh cell function remains unknown. In this study, we examined the regulatory role of BTLA in the development and function of Tfh cells. We found that CXCR5+ Tfh cells expressed higher levels of BTLA than did CXCR5− conventional CD4+ T cells. We also found that adoptive transfer of BTLA−/− CD4+ T cells, stimulated under Tfh cell-inducing conditions (Tfh-like cells), to wild-type (WT) mice induced more Ag-specific IgG2a and IgG2b production compared with that of WT Tfh-like cells. By contrast, another adoptive-transfer experiment using BTLA−/− mice as recipients showed that the expression of BTLA on B cells was not involved in the regulation of Tfh-like cell-mediated Ag-specific IgG responses. Moreover, the development of IL-21–producing CXCR5+ Tfh-like cells was significantly increased in BTLA−/− CD4+ T cells compared with WT CD4+ T cells. Furthermore, Tfh-like cell-mediated IgG responses were abolished when IL-21R−/− mice were used as recipients. These results suggest that BTLA signaling suppresses IL-21 production from Tfh cells and subsequent Tfh cell-mediated IgG responses.
Thymic Stromal Lymphopoietin in Cigarette Smoke-Exposed Human Airway Smooth Muscle
Authors: Smelter Dan F. , Sathish Venkatachalem , Thompson Michael A. , Pabelick Christina M. , Vassallo Robert , Prakash Y. S.
Published: July 2010

Thymic stromal lymphopoietin (TSLP) is a newly identified IL-7–like cytokine known to be expressed in airway biopsies of patients with asthma and chronic obstructive pulmonary disease. As both diseases may be induced or exacerbated by cigarette smoking, it is possible that TSLP represents an important link between cigarette smoke exposure and inflammatory signaling in the airways. In this regard, TSLP appears to also be expressed in airway smooth muscle (ASM); however, its role is unknown. In the current study, we examined TSLP and the TSLP receptor (TSLP-R) expression and function in human ASM cells under normal conditions and following exposure to cigarette smoke extract (CSE). Western blot analysis of human ASM cells showed significant expression of TSLP and TSLP-R, with increased expression of both by overnight exposure to 1 or 2% CSE. Furthermore, CSE increased TSLP release by ASM. In parallel experiments using enzymatically dissociated human ASM cells loaded with the Ca2+ indicator fura 2-AM and imaged using fluorescence microscopy, we evaluated the effects of CSE exposure on intracellular Ca2+ ([Ca2+]i) responses to agonist stimulation. [Ca2+]i responses to histamine were increased with overnight CSE exposure. Exposure to TSLP also resulted in elevated responses, which were blunted by TSLP and TSLP-R Abs. Importantly, the enhancing effects of CSE on [Ca2+]i responses were also blunted by these Abs. These effects were associated with CSE- and TSLP-induced changes in STAT5 phosphorylation. Overall, these novel data suggest that cigarette smoke, TSLP, and ASM are functionally linked and that cigarette smoke-induced increase in airway contractility may be mediated via ASM-derived increases in TSLP signaling.
Antigen-Specific Cytotoxicity by Invariant NKT Cells In Vivo Is CD95/CD178-Dependent and Is Correlated with Antigenic Potency
Authors: Wingender Gerhard , Krebs Philippe , Beutler Bruce , Kronenberg Mitchell
Published: July 2010

Invariant NKT (iNKT) cells are a unique subset of T lymphocytes that rapidly carry out effector functions following activation with glycolipid Ags, such as the model Ag α-galactosylceramide. Numerous studies have investigated the mechanisms leading to Th1 and Th2 cytokine production by iNKT cells, as well as the effects of the copious amounts of cytokines these cells produce. Less is known, however, about the mechanisms of iNKT cell cytotoxicity. In this study, we investigated the effect of Ag availability and strength, as well as the molecules involved in iNKT cytotoxicity. We demonstrate that the iNKT cell cytotoxicity in vivo correlates directly with the amount of CD1d expressed by the targets as well as the TCR affinity for the target glycolipid Ag. iNKT cells from spleen, liver, and thymus were comparable in their cytotoxicity in vitro. Surprisingly, we show that the Ag-specific cytotoxicity of iNKT cells in vivo depended almost exclusively on the interaction of CD95 (Fas) with CD178 (FasL), and that this mechanism can be efficiently used for tumor protection. Therefore, unlike NK cells, which rely mostly on perforin/granzyme-mediated mechanisms, the Ag-specific cytotoxicity of iNKT cells in vivo is largely restricted to the CD95/CD178 pathway.
Prognostic Outcomes of Tall Cell Variant Papillary Thyroid Cancer: A Meta-Analysis
Authors: Jalisi Scharukh , Ainsworth Tiffiny , LaValley Michael
Published: July 2010

Objective. To evaluate the prognosis of tall cell variant (TCV) compared to usual variant (UV) papillary thyroid cancer by comparing disease-related mortality and recurrence data from published studies.Methods. Ovid MEDLINE keyword search using “tall cell variant papillary thyroid cancer” was used to identify studies published in English that calculated disease-related mortality and recurrence rates for both TCV and UV.Results. A total of 131 cases of tall cell variant papillary thyroid cancer were reviewed. The combined odds ratio of recurrence for TCV compared to UV is 4.50 with a 95% confidence interval from 2.90 to 6.99. For disease-related mortality, the combined odds ratio for TCV was compared to UV of 14.28 with a 95% confidence interval from 8.01 to 25.46.Conclusion. Currently published data suggests that TCV is a negative prognostic indicator in papillary thyroid cancer and requires aggressive therapy. This meta-analysis provides the largest prognostic data series on TCV in the literature and clearly identifies the need for accurate pathological identification of TCV and its further study as an independent prognostic factor.
Dualité de Van den Bergh et structure de Batalin–Vilkoviskiĭ sur les algèbres de Calabi–Yau
Authors: Lambre Thierry
Published: July 2010

The abstract notion of Tamarkin–Tsygan calculus with duality gives Batalin–Vilkoviskiǐ structures in a general setting. We apply this technique to the case of Van den Bergh duality for algebras to prove that Calabi–Yau algebras are BV-algebras.
Index theory and partitioning by enlargeable hypersurfaces
Authors: Zadeh Mostafa Esfahani
Published: July 2010

In this paper we state and prove a higher index theorem for an odd-dimensional connected spin Riemannian manifold (M,g) which is partitioned by an oriented closed hypersurface N. This index theorem generalizes a theorem due to N. Higson in the context of Hilbert modules. Then we apply this theorem to prove that if N is area-enlargeable and if there is a smooth map from M into N such that its restriction to N has non-zero degree, then the scalar curvature of g cannot be uniformly positive.
Load Transfer in Truck Cab Structures under Initial Phase of Frontal Collision
Authors: Wang Enyang , Yoshikuni Yuki , Guo Qiushi , Nohara Tetsuo , Ishii Hideaki , Hoshino Hiroaki , Takahashi Kunihiro
Published: July 2010

A new parameter U** that represents load paths in structures is applied to a truck cab under collision. Since the main part of a compartment should be maintained in a linear elastic condition, a linear U** analysis can be applied. U** for the deformed body is statically calculated from the extracted deformation results of a crash simulation. A substitution-modulus method is applied to reproduce the material and geometrical nonlinearities. An index "m2-4msU**" is proposed as a standard condition for the truck cab. The predominant load paths along the floor member and the shear effect of the floor panel are demonstrated.
Atmospheric diurnal variations observed with GPS radio occultation soundings
Authors: Xie F. , Wu D. L. , Ao C. O. , Mannucci A. J.
Published: July 2010

Abstract. The diurnal variation, driven by solar forcing, is a fundamental mode in the Earth's weather and climate system. Radio occultation (RO) measurements from the six COSMIC satellites (Constellation Observing System for Meteorology, Ionosphere and Climate) provide nearly uniform global coverage with high vertical resolution, all-weather and diurnal sampling capability. This paper analyzes the diurnal variations of temperature and refractivity from three-year (2007–2009) COSMIC RO measurements in the troposphere and stratosphere between 30° S and 30° N. The RO observations reveal both propagating and trapped vertical structures of diurnal variations, including transition regions near the tropopause where data with high vertical resolution are critical. In the tropics the diurnal amplitude in refractivity shows the minimum around 14 km and increases to a local maximum around 32 km in the stratosphere. The upward propagating component of the migrating diurnal tides in the tropics is clearly captured by the GPS RO measurements, which show a downward progression in phase from stratopause to the upper troposphere with a vertical wavelength of about 25 km. At ~32 km the seasonal variation of the tidal amplitude maximizes at the opposite side of the equator relative to the solar forcing. The vertical structure of tidal amplitude shows strong seasonal variations and becomes asymmetric along the equator and tilted toward the summer hemisphere in the solstice months. Such asymmetry becomes less prominent in equinox months.
Relationships between mineral dust and cloud properties in the West African Sahel
Authors: Klüser L. , Holzer-Popp T.
Published: July 2010

Abstract. Aerosol cloud interactions are known to be of great importance to many parts of the climate system. Five years of observations from three different satellites (Aqua, ENVISAT and Meteosat Second Generation) are used to statistically analyse the relationship of mineral dust aerosol, separated from other aerosol species, with monsoon season cloud state in the West African Sahel domain. Additionally, observations of the Tropical Rainfall Measuring Mission are used for discrimination of dry and wet seasons. The aerosol-cloud-interactions are analysed separately by season and air mass in order to minimise spurious correlations with meteorological conditions. The detailed analysis uncovers different counteracting relationships of the mineral dust aerosol with the cloud state, which is also evident from an analysis of the spatial distribution patterns of cloud properties changes with dust activity. The aerosol-cloud relationships found from the analysis of this multiple year dataset are mainly consistent with the hypothesis of a suppression of convective activity, but also indications of lifetime enhancement and thus increased cloud cover and convective intensity are found in some subsets.
Source attribution of climatically important aerosol properties measured at Paposo (Chile) during VOCALS
Authors: Chand D. , Hegg D. A. , Wood R. , Shaw G. E. , Wallace D. , Covert D. S.
Published: July 2010

Abstract. Measurements of submicron aerosol composition, light scattering, and size distribution were made from 17 October to 15 November 2008 at the elevated Paposo site (25° 0.4' S, 70°27.01' W, 690 m a.s.l.) on the Chilean coast as part of the VOCALS1 Regional Experiment (REx). Based on the chemical composition measurements, a receptor modeling analysis using Positive Matrix Factorization (PMF) was carried out, yielding four broad source categories of the aerosol mass, light scattering coefficient, and a proxy for cloud condensation nucleus (CCN) concentration at 0.4% supersaturation derived from the size distribution measurements assuming an observed soluble mass fraction of 0.53. The sources resolved were biomass burning, marine, an urban-biofuels mix and a somewhat ambiguous mix of smelter emissions and mineral dust. The urban-biofuels mix is the most dominant aerosol mass component (52%) followed by biomass burning (25%), smelter/soil dust (12%) and marine (9%) sources. The average (mean±std) submicron aerosol mass concentration, aerosol light scattering coefficient and proxy CCN concentration were, 8.77±5.40 μg m−3, 21.9±11.0 Mm−1 and 548±210 cm−3, respectively. Sulfate is the dominant identified submicron species constituting roughly 40% of the dry mass (3.64±2.30 μg m−3, although the indentified soluble species constitute only 53% of the mass. Much of the unidentified mass is likely organic in nature. The relative importance of each aerosol source category is different depending upon whether mass, light scattering, or CCN concentration is being considered, indicating that the mean size of aerosols associated with each source are different. Marine aerosols do not appear to contribute to more than 10% to either mass, light scattering, or CCN concentration at this site. Back trajectory cluster analysis proved consistent with the PMF source attribution. 1 VOCALS: VAMOS Ocean-Cloud-Atmosphere-Land Study (VOCALS)VAMOS: Variability of American Monsoon System
Evidence for greater oxygen decline rates in the coastal ocean than in the open ocean
Authors: Gilbert D. , Rabalais N. N. , Díaz R. J. , Zhang J.
Published: July 2010

Abstract. In the global ocean, the number of reported hypoxic sites (oxygen <30% saturation) is on the rise both near the coast and in the open ocean. But unfortunately, most of the papers on hypoxia only present oxygen data from one or two years, so that we often lack a long-term perspective on whether oxygen levels at these locations are decreasing, steady or increasing. Consequently, we cannot rule out the possibility that many of the newly reported hypoxic areas were hypoxic in the past, and that the increasing number of hypoxic areas partly reflects increased research and monitoring efforts. Here we address this shortcoming by computing oxygen concentration trends in the global ocean from published time series and from time series that we calculated using a global oxygen database. Our calculations reveal that median oxygen decline rates are more severe in a 30 km band near the coast than in the open ocean (>100 km from the coast). Percentages of oxygen time series with negative oxygen trends are also greater in the coastal ocean than in the open ocean. Finally, a significant difference between median published oxygen trends and median trends calculated from raw oxygen data suggests the existence of a publication bias in favor of negative trends in the open ocean.
Characteristics of cold–warm variation in the Hetao region and its surrounding areas in China during the past 5000 years
Authors: Li M.-Q. , Ge Q.-S. , Hao Z.-X. , Zheng J.-Y. , He S.-F.
Published: July 2010

Abstract. Using six long-term temperature proxy data series derived from different natural evidences, including pollens and lake-sediments, we reconstructed a temperature series with a 100-yr time resolution for the past 5000 yr in the Hetao region and its surrounding areas. The resulting series suggests that, on a millennial timescale, temperatures in the region were higher than the mean value of the whole series during the 5000~2600 years before present (yr BP) period, and became relatively low comparing with the average temperature of the whole series after 2600 yr BP. Within these two periods, temperature fluctuations comprising numerous short, multi-centennial intervals also existed. A comparison between our reconstructed series and other series in China and across the Northern Hemisphere indicate that, on a long-term scale, cold–warm variations had been in phase across the whole hemisphere during the past 5000 years; on the century to multi-century scale, the beginning and the ending times varied from region to region, thus implying that climate changes did not occur simultaneously in different regions.
Tidal propagation in an oceanic island with sloping beaches
Authors: Chang Y.-C. , Jeng D.-S. , Yeh H.-D.
Published: July 2010

Abstract. In this study, a new analytical solution for describing the tide-induced groundwater fluctuations in oceanic islands with finite length and different slopes of the beaches is developed. Unlike previous solutions, the present solution is not only applicable for a semi-infinite coastal aquifer, but also for an oceanic island with finite length and different sloping beaches. The solution can be used to investigate the effect of higher-order components and beach slopes on the water table fluctuations. The results demonstrate the effect of higher-order components increases with the shallow water parameter or amplitude parameter and the water table level increases as beach slopes decrease.
Influence of cross-shelf water transport on nutrients and phytoplankton in the East China Sea: a model study
Authors: Zhao L. , Guo X.
Published: July 2010

Abstract. A three dimensional coupled biophysical model was used to examine the supply of oceanic nutrients to the shelf of the East China Sea (ECS) and its role in primary production over the shelf. The model consisted of two modules: the hydrodynamic module was based on a nested model with a horizontal resolution of 1/18 degree, whereas the biological module was a low trophic level ecosystem model including two types of phytoplankton, three elements of nutrients, and biogenic organic material. Model results suggested that seasonal variation in chlorophyll-a had a strong regional dependence over the shelf of the ECS. The area with high chlorophyll-a appears firstly at the outer shelf in winter, and gradually migrates toward the inner shelf (offshore region of Changjiang estuary) from spring to summer. Vertically, chlorophyll-a was generally homogenous from the coastal zone to the inner shelf. In the middle and outer shelves, high chlorophyll-a appeared in the surface in spring but moved to the subsurface from summer to early autumn. The annual averaged onshore flux across the shelf break was estimated to be 1.53 Sv for volume, 9.4 kmol s−1 for DIN, 0.7 kmol s−1 for DIP, and 18.2 kmol s−1 for silicate, which are supplied mainly from the northeast of Taiwan and southwest of Kyushu. From calculations that artificially increased the concentration of nutrients in the Kuroshio water, the additional oceanic nutrients were distributed in the bottom layer from the shelf break to the region offshore of Changjiang estuary from spring to summer, and appeared in the surface layer from autumn to winter. The contribution of oceanic nutrients to primary production over the shelf was found not only in the surface layer (mainly at the outer shelf and shelf break in winter and in the region offshore of Changjiang estuary in summer) but also in the subsurface layer over the shelf from spring to autumn.
Mortality in fibromyalgia: A study of 8,186 patients over thirty‐five years
Authors: Wolfe Frederick , Hassett Afton L. , Walitt Brian , Michaud Kaleb
Published: July 2010

Objective

To determine if mortality is increased among patients diagnosed as having fibromyalgia.

Methods

We studied 8,186 fibromyalgia patients seen between 1974 and 2009 in 3 settings: all fibromyalgia patients in a clinical practice, patients participating in the US National Data Bank for Rheumatic Diseases (NDB), and patients invited to participate in the NDB who refused participation. Internal controls included 10,087 patients with osteoarthritis. Deaths were determined by multiple source communication, and all patients were also screened in the US National Death Index (NDI). We calculated standardized mortality ratios (SMRs) based on age‐ and sex‐stratified US population data, after adjustment for NDI nonresponse.

Results

There were 539 deaths, and the overall SMR was 0.90 (95% confidence interval [95% CI] 0.61–1.26). Among 1,665 clinic patients, the SMR was 0.92 (95% CI 0.81–1.05). Sensitivity analyses varying the rate of NDI nonidentification did not alter the nonassociation. Adjusted for age and sex, the hazard ratio for fibromyalgia compared with osteoarthritis was 1.05 (95% CI 0.94–1.17). The standardized mortality odds ratio (OR) compared with the US general population was increased for suicide (OR 3.31, 95% CI 2.15–5.11) and for accidental deaths (OR 1.45, 95% CI 1.02– 2.06), but not for malignancy.

Conclusion

Mortality does not appear to be increased in patients diagnosed with fibromyalgia, but the risk of death from suicide and accidents was increased.
Organically Functionalized Mesoporous Silica by Co‐structure‐Directing Route
Authors: Gao Chuanbo , Che Shunai
Published: July 2010

This article provides a brief overview of functional mesoporous silica materials synthesized by the co‐structure‐directing route, which is distinct from conventional synthesis strategies. In these systems, organosilane serves as the co‐structure‐directing agent (CSDA), which provides critical interactions between the template and organic part of the organosilane to form mesostructures, thus retaining the organic groups on the pore surface after removal of the template by extraction. i) The formation of anionic‐surfactant‐templated mesoporous silicas (AMSs) has been achieved by the co‐structure‐directing route, which leads to a variety of mesostructures, porous properties and morphologies. ii) Other co‐structure‐directing systems for synthesizing mesoporous silicas have also been achieved, including systems using cationic surfactants and non‐surfactants, and systems using DNA for constructing nanofibers and DNA–silica liquid crystalline complexes. iii) Evidence for the regular arrangement of functional groups on the pore surface resulted from the co‐structure‐directing effect has been discussed. Also included is a brief description of the application, future requirements, and trends in the development of mesoporous materials by the co‐structure‐directing route.
Cerebral β‐amyloid detected by Pittsburgh compound B positron emission topography predisposes to recombinant tissue plasminogen activator‐related hemorrhage
Authors: Ly John V. , Rowe Christopher C. , Villemagne Victor L. , Zavala Jorge A. , Ma Henry , O'Keefe Graeme , Gong Sylvia J. , Gunawan Rico , Churilov Leonid , Saunder Tim , Ackerman Uwe , Tochon‐Danguy Henri , Donnan Geoffrey A.
Published: July 2010

Cerebral amyloid angiopathy (CAA) may be an important predisposing factor for the hemorrhagic complications of recombinant tissue‐type plasminogen activator (rt‐PA) therapy. We studied patients treated within 3 hours of onset of ischemic stroke with rt‐PA using positron emission tomography to compare Pittsburgh compound B (PiB) (a cerebral β‐amyloid ligand) retention in those with and without parenchymal hemorrhage (PH) and normal controls. Neocortical PiB retention was higher among patients with PH compared with patients without PH and normal controls, suggesting underlying CAA as a predisposing factor for rt‐PA–related hemorrhage. This finding may provide an impetus for the development of a more practical rapid pretreatment screening technique. Ann Neurol 2010
Natalizumab drug holiday in multiple sclerosis: Poorly Tolerated
Authors: Killestein Joep , Vennegoor Anke , Strijbis Eva M. , Seewann Alexandra , van Oosten Bob W. , Uitdehaag Bernard M. J. , Polman Chris H.
Published: July 2010

It has been suggested that natalizumab‐associated progressive multifocal leukoencephalopathy may be prevented by structured interruptions of treatment. Evidence supporting such a drug holiday is not yet available. Here we present initial observations in 10 multiple sclerosis patients who were stringently monitored up to 6 months after discontinuation of the infusions. Cumulatively, a combination of clinical relapse and new and/or enhanced lesions on magnetic resonance imaging had occurred in 7 of 10 patients. Although numbers are small, our data suggest that in patients who were switched to natalizumab because of disease activity despite first‐line treatment, a natalizumab drug holiday without reinstatement of alternate disease‐modifying therapy is poorly tolerated. Ann Neurol 2010
On the Reach of Chemical Synthesis: Creation of a Mini‐Pipeline from an Academic Laboratory
Authors: Wilson Rebecca M. , Danishefsky Samuel J.
Published: July 2010

In this retrospective, we recall some select cases of synergy between very challenging chemical synthesis and the identification of promising new candidates for pharmaceutics development. The progression from targets, often referred to as small molecules, to those of a size commonly associated with biologics (including glycoproteins) is also charted.
Preparation of heat‐resistant branched poly(styrene‐alt‐NPMI) by ATRP with divinylbenzene as the branching agent
Authors: Wenyan Huang , Huili Pan , Bibiao Jiang , Qiang Ren , Guangqun Zhai , Lizhi Kong , Dongliang Zhang , Jianhai Chen
Published: July 2010

Heat‐resistant branched poly(styrene‐alt‐NPMI) has been prepared via atom transfer radical polymerization (ATRP) of styrene (St) and N‐phenyl maleimide (NPMI) with divinylbenzene (DVB) as the branching agent in anisole at 80°C. Gas chromatography (GC) was used to determine the conversion of the reactants. Triple detection gel permeation chromatography (TD‐GPC) was used to analyze the copolymers. The results show that the polymerization yields primary chains predominately in the early stages and the formation of branched molecules occurs mainly when conversion is higher than 50%. As expected, higher dosage of DVB in our investigation range favors the formation of polymers with higher degree of branching. All the resulting branched poly(styrene‐alt‐NPMI)s have glass transition temperature (Tg) above 175°C, extrapolated initial weight loss temperature (Ti) above 410°C and statistic heat‐resistant index above 200°C. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
A bioeconomy vision of sustainability…
Authors: Chisti Yusuf
Published: July 2010

Consumption in a bioeconomy will have to be managed within acceptable limits. Copyright © 2010 Society of Chemical Industry and John Wiley & Sons, Ltd
Stahlfaserbeton nach DAfStb‐Richtlinie “Stahlfaserbeton”
Authors: Teutsch Manfred , Wiens Udo , Alfes Christoph
Published: July 2010

Stahlfaserbeton wird in Deutschland seit etwa Mitte der 1970er‐Jahre eingesetzt. Besondere Vorteile bietet die Zugabe von Stahlfasern beim Betonieren von Kellerwänden, Fundamenten, Fundamentplatten, Kellersohlen und Industrie‐ bzw. Hallenböden. Stahlfaserbeton ist ein Material mit besonderen Eigenschaften. Hervorzuheben ist seine große Duktilität, sowohl bei Druck‐ als auch bei Zugbeanspruchung. Mit Stahlfaserbeton können in den Bereichen Zugspannungen aufgenommen werden, in denen eine Einlage von Betonstahlbewehrung große Mühe bereitet. Die Berücksichtigung der Faserwirkung in den Bemessungsansätzen für die Grenzzustände der Tragfähigkeit und der Gebrauchstauglichkeit wird durch die vor kurzem erschienene DAfStb‐Richtlinie “Stahlfaserbeton” spezifiziert. Der Beitrag stellt die wesentlichen Inhalte der Richtlinie vor.
Hydraulische Reaktionen des Zements in Mörtel bei verschiedenen Parametern
Authors: Göske Jürgen , Winter Susanne , Pöllmann Herbert , Wenda Richard
Published: July 2010

Die Kryotransfer‐Rasterelektronenmikroskopie wird mittlerweile sehr häufig zur Erforschung von Abbindereaktionen in Zementen und anderen Baustoffen eingesetzt und kann heute als Standardverfahren angesehen werden. Ein wesentliches Interesse für industrielle Anwendungen besteht unter anderem darin, Untersuchungen des Zementleims in‐situ bereits ab der Wasserzugabe bzw. ab der ersten Minute der Hydratation in so genannten “Zeitschnitten” durchzuführen. In der vorliegenden Arbeit wird der Einsatz eines Kryotransfer‐Systems bei der Untersuchung der Abbindereaktionen des Zements in einem herkömmlichen Beton aufgezeigt. Als unterschiedliche Parameter wurden modellhaft Abbindezeiten von 1 Minute, 5 und 60 Minuten bei Abbindetemperaturen von 4 °C, 22 °C und 40 °C gewählt.

Hydraulic Reactions of Cement in Mortar at Different Parameters Analytical Observations by Means of Cryo‐Transfer‐Scanning‐Electron‐Microscopy

For the investigation of hydraulic reactions of cements and other building materials the cryo‐transfer scanning‐electron‐microscopy is frequently used by now. Today the cryo‐transfer technique is considered as a reference procedure. An essential concern in industrial applications is – amongst others – the insitu investigation of the cement paste at the very early state of hydration – just after the addition of water, respectively during the first minutes within so‐called “time‐cuts”. The present work illustrates the application of a cryo‐transfer system for the investigations on hydraulic reactions of conventional concrete. Exemplary parameters were curing times of 1 minute, 5 and 60 minutes at curing temperatures of 4 °C, 22 °C and 40 °C.
Der Eurocode 2 für Deutschland – Erläuterungen und Hintergründe
Authors: Fingerloos Frank
Published: July 2010

Der neue Eurocode 2: “Bemessung und Konstruktion von Stahlbeton‐ und Spannbetontragwerken – Teil 1‐1: Allgemeine Bemessungsregeln und Regeln für den Hochbau” (EC2‐1‐1) mit seinem Nationalen Anhang ist nach einer ausführlichen Erprobungsphase bereit zur bauaufsichtlichen Einführung in Deutschland. In mehreren Beiträgen sollen Erläuterungen und Hintergründe zu einigen Regelungen im Eurocode 2 und zu den Entscheidungen für Regeln im Nationalen Anhang vorgestellt werden, die entweder zu Änderungen gegenüber DIN 1045‐1 oder zu Abweichungen vom Eurocode 2 führten. Der Teil 3 enthält Erläuterungen zur Begrenzung der Spannungen, Rissbreiten und Verformungen.

The Eurocode 2 for Germany – Explanations and Backgrounds Part 3: Limitation of Stresses, Cracks and Deformations

The new Eurocode 2 “Design of concrete structures – Part 1‐1: General rules and rules for buildings” (EC2‐1‐1) and its National Annex has undergone a phase of detailed testing and is now ready for the implementation in Germany. In some articles should be given explanations and backgrounds of some rules in Eurocode 2 and of decisions for rules in the National Annex, which have been taken either to changes compared with DIN 1045‐1 or to differences to Eurocode 2. Article 3 contains explanations for the limitation of stresses, cracks and deformations.
Removal of nitrate and hexavalent uranium from groundwater by sequential treatment in bioreactors packed with elemental sulfur and zero‐valent iron
Authors: Luna‐Velasco Antonia , Sierra‐Alvarez Reyes , Castro Beatriz , Field Jim A.
Published: July 2010

The bioreduction of soluble hexavalent uranium (UVI) to insoluble tetravalent uranium (UIV) is an attractive bioremediation strategy for the clean‐up of contaminated groundwater. High levels of the common occurring co‐contaminant, nitrate (${\rm NO}_{{\rm 3}}^{{-} }$), can potentially interfere with uranium bioremediation. In this study, treatment of a synthetic groundwater containing a mixture of ${\rm NO}_{{\rm 3}}^{{-} }$ and UVI was investigated in a sulfur–limestone autotrophic denitrifying (SLAD) bioreactor that was coupled in series with a bioreactor packed with zero‐valent iron (Fe0, ZVI) and sand. An additional aim of the study was to explore the possible role of biological activity in enhancing the reduction of UVI by Fe0. The SLAD reactor removed ${\rm NO}_{{\rm 3}}^{{-} }$ efficiently (99.8%) at loadings of up to 20 mmol ${\rm NO}_{{\rm 3}}^{{-} }$ L d−1, with near stoichiometric conversion to benign dinitrogen gas (N2). The ZVI bioreactor subsequently removed uranium (99.8%) at high (0.22 mM) and low (0.02 mM) influent concentrations of the radionuclide. Aqueous uranium was reliably eliminated to below the maximum contaminant level of 30 µg L−1 (0.13 µM) when the ZVI reactor was operated at average empty bed hydraulic retention times as low as 2.3 h, demonstrating the feasibility of the sequential treatment strategy in packed bed bioreactors. Sequential extraction of the ZVI reactor packing confirmed that uranium was immobilized as UIV. Uranium removal was enhanced by microbial activity as confirmed by the increased rate of uranium removal in batch assays inoculated with effluent from the ZVI bioreactor and spiked with Fe0 compared to abiotic controls. Biotechnol. Bioeng. 2010;107: 933–942. © 2010 Wiley Periodicals, Inc.