bluuebunny/crossref_metadata_2025 huggingface dataset:
Experiment Research of Polishing Capability of Magnetorheological Finishing with a Small Permanent Magnet Ball-End Tool
Authors: Su Yin Rui , Li Dan , Liu He Nan , Chen Ming Jun , Peng Hui
Published: October 2013

In order to resolve the difficulty in polishing work of complex shape, a new magnetorheological finishing (MRF) technology with a small permanent magnet ball-end tool is developed. Rotary symmetrical magnetic field generated by the small permanent ball-end tool, stiffen a magnetic fluid which is delivered by a slender needle tubing, in contact with a workpiece. The permanent magnet tool is hold by a slender cylindrical shank, so it won’t interfere with workpiece when polishing deep concave cavity. A prototype apparatus is established to study the processing characteristics of this polishing method. MRF spots are taken on stationary workpiece to study the influence of several processing parameters on the material removal function, such as, spindle speed, included angle and minimum gap between polishing tool and finishing-surface. A 3×3mm square on a fused quartz (FS) is polished and the surface roughness decrease from 81nm Ra to 1.5nm Ra after polishing for 100min.
Study on Three-Way Pipe’s Internal High Pressure Forming Simulation
Authors: Wang Shi Gang , Gao Fu Sheng , Cheng Feng Lan , Guo Qiang
Published: October 2013

Internal high pressure forming is a kind of the modern plastic processing technology. Using liquid as the pressure transmitting medium, explore the effect of internal high pressure parameter on the three passing pipe technique, internal high pressure forming technique is applied on the three-dimensional shape parts deformation. In this study, we simulate the three-way pipe process by finite element software, analyze the forming force influence to the tube forming quality and get the changeable regulation of the pipe wall thickness with conclusion of the wall thickness variation, which provides the reference data and guidance for the actual production of the three-way pipe.
Determination of AISI 1045 Steel Constitutive Model by Cutting Experiment Inverse Analysis Methods
Authors: Qiu Xin Yi , Li Peng Nan , Wu Shun Xing , Yan Zhi Hui , Tang Si Wen
Published: October 2013

Based on the Merchant shear angle theory, two-dimensional high-speed orthogonal cutting experiments with an ‘OXCUT’ flow stress inverse procedure were used to determine the Johnson-Cook constitutive constants of the AISI 1045 steel (195HB). The constitutive constants obtained in the strain range 1.3-1.4 and large strain rate range 6106-7106/s. It is verified by experiments, and the result shows that the cutting forces are within the permissible error range. Compared the constitutive model with Hu’s, the cutting forces of this constitutive model of FEM are closer to the measurement, while the feed force has a relatively larger gap.
Finite Element Simulation of PCD Tool Cutting Titanium Alloy
Authors: Liu Xian Li , Zhang Jia Yi , Wang Yu , Yue Cai Xu , Liu Fei
Published: October 2013

Titanium alloy is widely applied in various fields, but it’s a sort of difficult-to-cut material. In this paper, DEFORM-3D is used to carry on a simulation of PCD tool milling Ti6A14V. Variation curves of cutting temperature and cutting force are obtained by changing cutting speed, feed per tooth and axial cutting depth. Further, the effect of cutting parameters on cutting temperature and cutting force is revealed. The research shows that cutting temperature and cutting force increase with cutting parameters. In addition, single factor experiments are conducted to verify that the results of the experiments are in consistent with those of the simulation, and that the simulation model is correct. The results will provide new methods for studies of cutting temperature and cutting force of PCD tool milling Ti6A14V.
Static and Dynamic Analyses of Beam in Gantry-Type Milling Machine
Authors: Zhao Bin , Zhang Song , Chen Yan , Wang Qian Feng , Zhao Guo Qiang
Published: October 2013

The static and dynamic characteristics of the key components of machine tools should be studied in order to improve quality of work pieces and manufacture efficiency. In this paper, the static and dynamic analyses of the beam in the gantry-type milling machine were conducted with ANSYS Workbench,one of finite analysis software. The static simulated results indicate that the maxiumum deformation appears at the upper guide and the max strain and stress at the position connecting with columns. The modal analysis shows the bending and torsion deformations are the main factors influencing the dynamic performances of the beam when working frequencies are close to the first six natural frequencies; therefore, the selected spindle rotational speed should keep away from the natural frequencies of the beam when planning the cutting parameters.
Study on Spring Rubber Parameter Optimization in Damping Boring Bar
Authors: Wang Yu , Liu Li Jia , Ma Tian Yu , Xu Cheng Yang , Hou Duan Yang
Published: October 2013

Passive dynamic damping system in damping boring bar is made of rubber, damping blocks and damping liquid. These parameters ,which including the elasticity of the spring rubber, the mass of the damping blocks and the characteristic of the damping liquid, will have influence on damping property. This paper mainly studies the influence of spring rubber parameter on damping property. Frequency response curve of spring rubber can be got by simulation, spring rubber static analysis by ANSYS and damping boring bar vibration simulation by ADAMS. After verification by simulation, the model and resolving method of parameters can provide theoretical basis of actual application and design.
Research and Analysis of Stiffness Properties of New Vehicle Air Spring
Authors: Lin Lin , Wang Tong Yu , Huang Yu Xin , Wang Li Meng , Wang Hong Yi
Published: October 2013

Based on the analysis of a new type of air spring and the nonlinear finite element theory, this paper, taking the mechanical properties of the new type air spring into consideration, put forward an assessment method: the Mooney-Rivlin model with higher order term simulates rubber layer, the rebar model represents the cord thread layer, the stiffness of the listrium and the controllable damping shock absorber is rigid body, the gas flow and the pneumatophore are in coupling. In addition, the method has been tested and verified by applying to a new type vehicle air spring. This paper offers a new assessment method for the development of air springs in vehicle suspension.
The Simulation Analysis and Experimental Research on the Process of PCBN Cutting Super-Alloy
Authors: Zhai Yuan Sheng , Qiao Shuai , Liu Xian Li , Hu Qiang
Published: October 2013

Ni-based super-alloy GH4169 that is most widely used in aerospace is one of the most difficult-to-cut materials, which can be machined by Polycrystalline Cubic Boron Nitride (PCBN) tool. In this paper, the cutting process of super-alloy GH4169 with PCBN tool is researched by simulation, combing with the comparison and verification of experiment. The change rules of cutting temperature and force under different cutting parameters are obtained in this study. The reasonable parameter ranges of high efficiency cutting are proposed in cutting parameter optimization, in order to provide a reference for high efficiency machining of super-alloy GH4169 with PCBN tool.
Analysis of Generation and Curling Deformation Mechanism of Large Chips in Heavy-Duty Cutting
Authors: Wu Ming Yang , Sun Shou Hui , Cheng Yao Nan , Yan Fu Gang , Hu Qiang , Liu Li
Published: October 2013

In heavy-duty cutting, large chips produced are wide, thick and of complex shapes. If the large chips are not controlled reasonably they will heavily influence the machining efficiency. This article researches on the generation process of large chips, and is combined with the research method of finite element simulation to establish curling model of large chips in heavy-duty cutting process. Through analyzing the fracture strain and cut strain suffered by the chips in the curling process of large chips and enlarging the large chips using electron microscopy, the generation and curling deformation law is revealed. And analyzing generation and curling mechanism of large chips can provide theoretical basis for the generation and control of ideal chips in heavy-duty cutting process.
Experimental Study on Low Alloy TRIP Steel Grinding Ball
Authors: Ma Shi Hui
Published: October 2013

Grinding ball is grinding body of ore, cement, coal and other solid materials in the ball mill grinding and is one of the biggest consumption in wearable element of powder industry. In this paper, using the principle of transformation induced plasticity, reinforcement, toughening, according to the new design ideas, a kind of TRIP steel is designed in order to improve wear-resisting property of the grinding ball.
A New Method of Variable Forming Point Grinding Revolving Parts with Convex Function Generatrix
Authors: Wang Shao Lei , Lin Bin , Wang Yan , Cao Xiao Yan
Published: October 2013

This paper, presents an improved method for Face grinding with variable forming point,which aims at cup wheel face grinding convex function generatrix revolving parts.
Abrasive-Assisted Electroforming of Nickel on Translational Cathode
Authors: Zhu Zeng Wei , Wang Dong , Ren Jian Hua
Published: October 2013

Spherical abrasives were employed to polish the growing deposited layer during nickel electroforming process. On a translational flat cathode, nickel deposits with distinct polishing mark were obtained. It was found that the abrasive polishing can help to improve the microstructure and increase the mechanical properties of the nickel deposits. Compared with the deposits prepared with traditional method, the microstructure became more homogeneous and the microhardness increased nearly two times. The increase of current density led to coarse structure and lower microhardness.
Safety and Stability Analysis of the Ship Loader during Shipping
Authors: Liu Peng Fei , Lin Bin , Zhang Xiao Feng , Zhang Xu , Zhou Meng Long
Published: October 2013

The influence which is brought by the variation law of the whole machines center of gravity position when the telescopic boom and fixed boom at different pitch angles during shipping is been given by using ANSYS and MATLAB. Meanwhile, the influence which the swing arms different pitch angles bring to the safety of the ship loaders own structure is also being analyzed in this paper. Finally, the best placement angle of the ship loaders swing arm is given based on the comprehensive analysis of all factors.
Simulation of the Effect of Sintering Temperature on Microstructure Evolution in Nanocomposite Ceramic Tool Materials
Authors: Cheng Hong Mei , Huang Chuan Zhen , Wang Xiu Ye
Published: October 2013

A Monte Carlo Potts model coupled with sintering temperature for the sintering process of nanocomposite ceramic tool materials is proposed, the relation between grain growth and sintering temperature is presented. The grain growth process at different sintering temperature is investigated in this model, and the effect of sintering temperature on microstructure evolution is discussed, it is found that the mean grain size increases with the increase of sintering temperature during simulation, and nanoparticles are easier to enter into matrix grains to form intragranular-type microstructure at higher temperature. The simulation results are in accordance with the experimental observations.
Some Observations in Grinding Surface Quality of FRCMC
Authors: Cao Xiao Yan , Lin Bin , Wang Yan , Wang Shao Lei
Published: October 2013

FRCMCs have potential applications in aerospace and other high-tech fields. According to FRCMCs anisotropic and non-homogeneous structure, the composites surface characteristics are different from metal material. Fiber orientations play the decisive role in grinding surface quality of woven ceramic matrix composites. This paper investigates the relationship between fiber orientations and grinding surface quality. Using a non-contact optical measurement instrument, the method was developed on 2.5D SiO2/SiO2 composite. Through a series of measuring experiments, it was found that greater grinding surface quality occurred at a fiber orientation 90, but poorer grinding surface took place at a fiber orientation 0. Meanwhile there were less surface defects at acute fiber orientation angle than at obtuse angle. The research obtained will be an important technical support on improving the processing quality of FRCMC.
Research on Machinability of SF6 in Diamond Cutting with Cutting Fluid
Authors: Jia Peng
Published: October 2013

For the technology of diamond cutting of optical glass, the machinability of glass is poor, which hindering the practical application of this technology. In order to investigate and ameliorate the machinability of glass, and achieve optical parts with the satisfied surface quality and dimensional accuracy, this paper first conducted SF6 indentation experiment by Vickers microhardness instrument, and then the scratching tests with increasing depths of cut were conducted on glass SF6 to evaluate the influence of the cutting fluid properties on the machinability of glass. Based on this, turning tests were carried out, and the surface quality of SF6 was assessed based on the detections of the machined surfaces roughness. Experimental results indicated that compared with the process of dry cutting, the machinability of glass SF6 can be improved by using the cutting fluid.
Research on Micromechanical Drilling of Micro-Hole Array in PVC Mask
Authors: Fu Wen Kai , He Ning , Li Liang , Zhao Meng , Bian Rong
Published: October 2013

Globalization of the micro manufacturing technology has become a trend. This technology has been widely used in many fields, especially in aerospace field and biological medicine. The electrolytic PVC mask of micro-hole array is difficult to machine because of the high positional accuracy of the micro-hole array, small diameter of the holes and the high requirement of machining quality. This paper studied the influence of workpiece property, optimization of machining parameters, and chips removing in machining of the electrolytic PVC mask using micromechanical drilling. A feasible method with high efficiency is presented.
Effects of Nano-Al2O3 on the Mechanical Property and Microstructure of Nano-Micro Composite Self-Lubricating Ceramic Tool Material
Authors: Yi Ming Dong , Xu Chong Hai , Chen Zhao Qiang , Wu Guang Yong
Published: October 2013

A new nanomicro composite self-lubricating ceramic tool material was prepared with vacuum hot pressing technique. The effect of nanoAl2O3 powders on the microstructure and mechanical properties of nanomicro composite self-lubricating ceramic tool material was investigated. With the increase of nanoAl2O3 content, the hardness and fracture toughness first up then down. When the nanoAl2O3 content is 4 vol.%, the flexural strength, hardness and fracture toughness reaches 562 MPa, 8.46 MPa·m1/2 and 18.95 GPa, respectively. The microstructure and mechanical property of nanomicro composite self-lubricating ceramic tool material can be improved by the grain refinement strengthening of nanoAl2O3.
Collaborative Refinement Method for Process Innovation Knowledge Network
Authors: Guo Biao , Hou Zhong Bin , Geng Jun Hao , Wang Gang Feng
Published: October 2013

Accumulating a large number of process innovation knowledge (PIK) is the prerequisite and basis for process innovation.PIK can be gradually refined by using. Hence, how to ensure the correctness of the PIK collaborative refinement is the basic work of knowledge accumulation. This paperproposes a construction method of PIK network by the imitating of biological neural network, and arefinement methodof PIKby the imitating of neural stimulation conduction. Because the refining processes are iterative, the refinement of process innovation needsa specificeditingmechanism and control mechanism, which allow multi-userto engage in collaborative editing and protect the consistency of collaborative editing result. Using the refinement method of PIK,it is possible to convert the discrete, rough knowledge into a PIK network that can effectively solve the process problems.
Research on Deformation Behavior of 2024 H18 Aluminum Alloy at Elevated Temperature
Authors: Chen Guo Liang , Wang Ning , Chen Ming He
Published: October 2013

Uniaxial tensile deformation behavior of 2024 H18 aluminum sheet alloys was studied in the hot forming process with synchronous cooling temperature range of 300°C~475°C and in the strain rate range of 0.0005/s~0.1/s. The effects of temperature and strain rate on stress, elongation to facture were analyzed. And a constitutive model was proposed to describe the relationship of true stress-true stain by multiple linear regression analysis. It was found that the forming temperature and strain rate have great effect on the hot forming behavior of the alloys. The max stress reduced greatly with the increasing of temperature or reducing of strain rate, while the tensile elongation tended to rise first and then fall with the increasing of temperature and strain rate. The forming of 2024 H18 aluminum alloy at elevated temperature occurred with the strain hardening and dynamic softening. The constitutive model of 2024 H18 aluminum alloy agrees well with the experimental data.
Study on Diagnosis of Engineering Mechanical Fault Based on Internet of Things
Authors: Yang Zhi Bo , Liu Kai Fei
Published: October 2013

Based on the status of diagnosis of engineering mechanical fault, the service platform was set up. It could detect the condition of engineering mechanical equipment at any time by the communication technology ZigBee and GPRS and analyses the development tendency of equipment in order to diagnose the fault of engineering mechanical equipment and sustain it.
The Design and Fabrication of Dimples Pattern on the Surface of UHMWPE
Authors: Zhang Bo , Wang Xiao Lei
Published: October 2013

Tribological problems are the major obstacle that limits the long-term using of ultra high molecular weight polyethylene (UHMWPE) in artificial joints. Many efforts have been made to improve the tribological properties of UHMWPE mainly by promoting the structure, morphology and mechanical properties of UHMWPE. In this paper, inspired from the natural joint, the micro-scale texture has been introduced to improve the tribological properties of UHMWPE. The micro-imprint lithography technology has been adopted to fabricate the textured UHMWPE. The profile of textured UHMWPE shows that the quality of textured UHMWPE is good. The result of tribological tests shows that the micro-scaled surface texture can remarkably reduce friction on UHMWPE.
Dye Sensitized Solar Cell: A Summary
Authors: Rokesh Karuppannan , Pandikumar Alagarsamy , Jothivenkatachalam Kandasamy
Published: October 2013

Dye sensitized solar cell (DSSC) devices incorporating organic and inorganic materials have found a host of applications. The search for low-cost, high efficient and flexible devices has lead to a remarkable increase in the research and development of solar cell. The current review, describes the constitution components of DSSC in a detailed manner and their development and challenges are also discussed. We focused on various structural modifications in wide band gap nanocrystalline semiconductor materials for an efficient electron transfer to reduce the recombination rate. Fruitful attempts have been made to design new molecular dyes for the wide range of absorption in the visible region. Co-Sensitization is an appropriate technique to enhance the absorption range of dye molecules and to increase the efficiency of solar cell. Moreover hole transport materials, there are the efficient tool to replace redox couple based liquid electrolyte and it produce stable solid state DSSC. The successful modification of counter electrode with different morphology promotes the rate electron transfer into electrolyte. This review also covers the update technology to construct efficient, stable and flexible dye sensitized solar cell.
Effect of Material Parameters on the Optical Properties of Dye-Sensitized Solar Cell Photoanode
Authors: Singh Amrik , Mohan Devendra , Ahlawat Dharamvir Singh , Jyoti Divya
Published: October 2013

The presented theoretical analysis predicts the behaviour of optical properties of film with regards to materialistic parameters of the photoanode of dye-sensitized solar cell using the theory of dispersive transport. The porous nature of photoanode is considered for the simulation task. The variations in refractive index and absorption index of the semiconductor film with change in the values of thickness and porosity are studied by using finite element method. The theoretically demonstrates that refractive index increases with the increase in thickness and decreases with increase in porosity but absorption index shows a monotonic behaviour.
Positron Annihilation Characterization of TiO2 Doped Polystyrene
Authors: Acharya Aman Deep
Published: October 2013

TiO2 doped polystyrene thin films fabricated by solution cast method. The effect of dopant concentrations has been studied for the structural, morphological, optical and defects properties. The XRD results revealed that the degree of crystallinity remains largely invariant due to the presence of the polymer. Interesting results have been obtained from optical measurement which depicted that there is increase in UV-shielding efficiency with the increase in the dopant concentration as the absorbance was found to be maximum in case of UV region. Surface morphology of the films shows a rod like structure for 0.25 wt% of TiO2, while for higher concentrations the TiO2 clusters were obtained. The positron lifetime results reveal that the free volume hole concentration decreased with the increase in TiO2 concentration as intensity of o-positronium decreases with the increase in concentration of TiO2 doping.
Recent Advances in SnO2 Based Photo Anode Materials for Third Generation Photovoltaics
Authors: Pari Baraneedharan , Chidambaram Siva , Kasi Nehru , Muthusamy Sivakumar
Published: October 2013

Dye Sensitized Solar Cell (DSSC) based on metal oxide photo anode is of greater interest at the present scenario. The light harvesting capability of the photo anode is the most crucial factor in determining the efficiency of DSSC. Thus to decide on suitable photo anode to attain greater efficiency is critical confront. The wide band gap (3.6eV) and higher electron mobility (me ~ 250 cm2V-1S‑1) of SnO2put together a promising material when compared to other photo electrode materials . Besides, its low sensitivity towards UV makes them more stable for a long time. This review will focus on recent progress in development of SnO2and hybrid SnO2based photo anode material and its allied key issues based on articles published in the last five years. A short introduction about the current energy scenario, DSSC principle and working will be presented followed by a brief description about the importance of photo anode in DSSC. Subsequently a complete review on SnO2and hybrid SnO2photo anode materials will be explained together with the recent year reports considering all the challenges and perspectives related to DSSC.
Fernie Formation and Minnes Group (Jurassic and lowermost Cretaceous), northern Rocky Mountain Foothills, Alberta and British Columbia
Authors: Stott D F
Published: October 2013

The Fernie Formation and Minnes Group represent infilling of a marine trough, grading from mid-basin to alluvial plain deposits. This report establishes a regional stratigraphic framework, outlines the correlations and facies, and documents the ages of rocks
ranging from earliest Jurassic (Hettangian) to Early Cretaceous (Late Valanginian). The lower and upper boundaries are defined by regional unconformities. The Jurassic-Cretaceous boundary lies within beds transitional between the Fernie Formation and the Minnes Group.
The Fernie Formation of this region, consisting of marine sediments, is not strictly comparable with the Fernie sequence of the southern and central Foothills. An unconformity within the formation truncates Middle and Lower Jurassic strata.
The Minnes Group consists of marine and nonmarine sediments, including quartzose and cherty sandstone, siltstone, conglomerate, shale, and coal- bearing beds. In the northern half of the area, the Minnes Group is divided into four formations (in ascending order): Monteith, Beattie Peaks, Monach and
Bickford. In the southern half, equivalent beds are included in the Monteith and Gorman Creek formations. Partly equivalent beds are assigned to the Nikanassin Formation of the northern Alberta Foothills.
Marine cycles within these Late Jurassic and Early Cretaceous rocks record a complex interaction of tectonic and sea- level processes, and the initial development of a foredeep on the eastern side of the Cordilleran Orogen. Clastic sediments were derived from a cratonic and Cordilleran source.
The Fernie and Minnes rocks form potential source and reservoir rocks for hydrocarbons. The Minnes Group has produced limited amounts of natural gas and has been explored to a limited extent for coal.
Management of sizeable carotid body tumor: Case report and review of literature
Authors: Elsharawy Mohamed A , Alsaif Hind , Elsaid Aymen , Kredees Ali
Published: October 2013

Carotid body tumor is a paraganglioma derived from the neural crest. It arises from the carotid body which acts as a vascular chemoreceptors and is usually located at the carotid bifurcation. Sizeable (Shamblin III, >5 cm size) tumors are large and typically encase the carotid artery requiring vessel resection and replacement. Management of such tumors carries a high risk of postoperative mortality and morbidity rates specially with regards to neurovascular complications. We report a case of sizeable tumor which was surgically removed with minimal complications.
Aqueous-phase photochemical oxidation and direct photolysis of vanillin – a model compound of methoxy-phenols from biomass burning
Authors: Li Y. J. , Huang D. D. , Cheung H. Y. , Lee A. K. Y. , Chan C. K.
Published: October 2013

Abstract. We present here experimental results on aqueous-phase (A) photochemical oxidation (with UV and OH radicals generated from H2O2 photolysis) and (B) direct photolysis (with only UV irradiation) of a methoxy-phenol, vanillin (VL), as a model compound from biomass burning. Both on-line aerosol mass spectrometric (AMS) characterization and off-line chemical analyses were performed. AMS analyses of dried atomized droplets of the bulk reacting mixtures showed that VL almost entirely evaporates during the drying process. Large amounts of organic mass remained in the particle phase after reactions under both conditions. Under condition (A), AMS measured organic mass first increased rapidly and then decreased, attributable to the formation of non-volatile products and subsequent formation of smaller and volatile products, respectively. The oxygen-to-carbon (O:C) ratio of the products reached 1.5 after about 80 min, but dropped substantially thereafter. In contrast, organic mass increased slowly under condition (B). The O:C ratio reached 1.0 after 180 min. In off-line analyses, small oxygenates were detected under condition (A), while hydroxylated products and dimers of VL were detected under condition (B). Particle hygroscopic growth factor (GF) and cloud condensation nuclei (CCN) activity of the reacting mixtures were found to be dependent on both organic volume fraction and the degree of oxygenation of organics. Results show that (1) aqueous-phase processes can lead to the retention of a large portion of the organic mass in the particle phase; (2) once retained, this portion of organic mass significantly changes the hygroscopicity and CCN activity of the aerosol particles; (3) intensive photochemical oxidation gave rise to an O:C ratio as high as 1.5 but the ratio decreased as further oxidation led to smaller and more volatile products; and (4) polymerization occurred with direct photolysis, resulting in high-molecular-weight products of a yellowish color. This study demonstrates that aqueous-phase reactions of a methoxy-phenol can lead to substantial amount of secondary organic aerosol (SOA) formation. Given the vast amount of biomass burning input globally, model representation of either the SOA budget or their subsequent effects would not be adequate if the contribution of SOA formation from aqueous-phase reactions of methoxy-phenols is not considered.
Global monitoring of terrestrial chlorophyll fluorescence from moderate-spectral-resolution near-infrared satellite measurements: methodology, simulations, and application to GOME-2
Authors: Joiner J. , Guanter L. , Lindstrot R. , Voigt M. , Vasilkov A. P. , Middleton E. M. , Huemmrich K. F. , Yoshida Y. , Frankenberg C.
Published: October 2013

Abstract. Globally mapped terrestrial chlorophyll fluorescence retrievals are of high interest because they can provide information on the functional status of vegetation including light-use efficiency and global primary productivity that can be used for global carbon cycle modeling and agricultural applications. Previous satellite retrievals of fluorescence have relied solely upon the filling-in of solar Fraunhofer lines that are not significantly affected by atmospheric absorption. Although these measurements provide near-global coverage on a monthly basis, they suffer from relatively low precision and sparse spatial sampling. Here, we describe a new methodology to retrieve global far-red fluorescence information; we use hyperspectral data with a simplified radiative transfer model to disentangle the spectral signatures of three basic components: atmospheric absorption, surface reflectance, and fluorescence radiance. An empirically based principal component analysis approach is employed, primarily using cloudy data over ocean, to model and solve for the atmospheric absorption. Through detailed simulations, we demonstrate the feasibility of the approach and show that moderate-spectral-resolution measurements with a relatively high signal-to-noise ratio can be used to retrieve far-red fluorescence information with good precision and accuracy. The method is then applied to data from the Global Ozone Monitoring Instrument 2 (GOME-2). The GOME-2 fluorescence retrievals display similar spatial structure as compared with those from a simpler technique applied to the Greenhouse gases Observing SATellite (GOSAT). GOME-2 enables global mapping of far-red fluorescence with higher precision over smaller spatial and temporal scales than is possible with GOSAT. Near-global coverage is provided within a few days. We are able to show clearly for the first time physically plausible variations in fluorescence over the course of a single month at a spatial resolution of 0.5° × 0.5°. We also show some significant differences between fluorescence and coincident normalized difference vegetation indices (NDVI) retrievals.
Seasonal dissolved inorganic nitrogen and phosphorus budgets for two sub-tropical estuaries in south Florida, USA
Authors: Buzzelli C. , Wan Y. , Doering P. H. , Boyer J. N.
Published: October 2013

Abstract. Interactions among geomorphology, circulation, and biogeochemical cycling determine estuary responses to external nutrient loading. In order to better manage watershed nutrient inputs, the goal of this study was to develop seasonal dissolved inorganic nitrogen (DIN) and phosphorus (DIP) budgets for the two estuaries in south Florida, the Caloosahatchee River estuary (CRE) and the St. Lucie Estuary (SLE), from 2002 to 2008. The Land–Ocean Interactions in the Coastal Zone (LOICZ) approach was used to generate water, salt, and DIN and DIP budgets. Results suggested that internal DIN production increases with increased DIN loading to the CRE in the wet season. There were hydrodynamic effects as water column concentrations and ecosystem nutrient processing stabilized in both estuaries as flushing time increased to >10 d. The CRE demonstrated heterotrophy (net ecosystem metabolism or NEM < 0.0) across all wet and dry season budgets. While the SLE was sensitive to DIN loading, system autotrophy (NEM > 0.0) increased significantly with external DIP loading. This included DIP consumption and a bloom of a cyanobacterium (Microcystis aeruginosa) following hurricane-induced discharge to the SLE in 2005. Additionally, while denitrification provided a microbially-mediated N loss pathway for the CRE, this potential was not evident for the SLE where N2 fixation was favored. Disparities between total and inorganic loading ratios suggested that the role of dissolved organic nitrogen (DON) should be assessed for both estuaries. Nutrient budgets indicated that net internal production or consumption of DIN and DIP fluctuated with inter- and intra-annual variations in freshwater inflow, hydrodynamic flushing, and primary production. The results of this study should be included in watershed management plans in order to maintain favorable conditions of external loading relative to internal material cycling in both dry and wet seasons.
Nitrous Oxide (N2O) production in axenic Chlorella vulgaris microalgae cultures: evidence, putative pathways, and potential environmental impacts
Authors: Guieysse B. , Plouviez M. , Coilhac M. , Cazali L.
Published: October 2013

Abstract. Using antibiotic assays and genomic analysis, this study demonstrates nitrous oxide (N2O) is generated from axenic Chlorella vulgaris cultures. In batch assays, this production is magnified under conditions favouring intracellular nitrite accumulation, but repressed when nitrate reductase (NR) activity is inhibited. These observations suggest N2O formation in C. vulgaris might proceed via NR-mediated nitrite reduction into nitric oxide (NO) acting as N2O precursor via a pathway similar to N2O formation in bacterial denitrifiers, although NO reduction to N2O under oxia remains unproven in plant cells. Alternatively, NR may reduce nitrite to nitroxyl (HNO), the latter being known to dimerize to N2O under oxia. Regardless of the precursor considered, an NR-mediated nitrite reduction pathway provides a unifying explanation for correlations reported between N2O emissions from algae-based ecosystems and NR activity, nitrate concentration, nitrite concentration, and photosynthesis repression. Moreover, these results indicate microalgae-mediated N2O formation might significantly contribute to N2O emissions in algae-based ecosystems (e.g. 1.38–10.1 kg N2O-N ha−1 yr−1 in a 0.25 m deep raceway pond operated under Mediterranean climatic conditions). These findings have profound implications for the life cycle analysis of algae biotechnologies and our understanding of the global biogeochemical nitrogen cycle.
Les albums photos de Kate et de Fred. Petit essai de décryptage d’un fonds photographique
Authors: Genest Bernard
Published: October 2013

Il y a plusieurs années, l’auteur de cet article faisait l’acquisition, chez un brocanteur de Sherbrooke, d’albums photos datant des années 1920-1930, sans références à leur provenance. L’intérêt du fonds venait de son potentiel documentaire en dépit du fait qu’il était sorti de son contexte d’origine. Le fonds contenait des images montrant des gens dans l’exercice d’activités diverses, aussi bien techniques, sportives, sociales que culturelles, mais aussi des lieux (principalement Québec, le lac Saint-Joseph, Sherbrooke et le lac Magog), des sites, un environnement construit et paysager, des moyens de transports, des outils et des objets usuels. Genest tente de montrer qu’il est possible, à partir d’une lecture attentive des images, de les faire parler suffisamment pour en tirer des informations relatives à l’époque, au milieu social, aux activités et aux valeurs des principaux personnages qui y figurent, jusqu’à reconstituer des pans de leur vie sur la seule base de leur pouvoir d’évocation.
Role of Osteopathic Structural Diagnosis and Osteopathic Manipulative Treatment for Diabetes Mellitus and Its Complications
Authors: Johnson Amy W. , Shubrook Jay H.
Published: October 2013

Osteopathic physicians have a unique opportunity to affect the US epidemic of type 2 diabetes mellitus (T2DM). Osteopathic physicians make up a disproportionately high number of primary care physicians who are on the front lines of managing T2DM. In addition, the unique training of osteopathic physicians allows them to direct additional diagnostic and treatment modalities toward the musculoskeletal complications of diabetes. The present review surveys the literature that explores the effects of osteopathic structural diagnosis of and osteopathic manipulative treatment for T2DM, as well as the management and prevention of complications. The authors reviewed the databases for PubMed, Google Scholar, and The Journal of the American Osteopathic Association. Although the available literature is limited, the authors identify areas in which osteopathic-focused research has shown benefits and in which future research should be directed.
Tobacco Dependence Curricula in US Osteopathic Medical Schools: A Follow-up Study
Authors: Griffith Brian N. , Montalto Norman J. , Ridpath Lance , Sullivan Kendra
Published: October 2013

Context: Tobacco use is the leading preventable cause of illness and death in the United States. A 1998 survey of US osteopathic medical schools identified deficiencies in tobacco dependence curricula.

Objective: To assess the current content and extent of tobacco dependence education and intervention skills in US osteopathic medical school curricula.

Design: An electronic survey.

Setting: Osteopathic medical schools with students enrolled for the 2009-2010 academic year.

Participants: Twenty-seven osteopathic medical school deans or their designated administrators.

Main Outcome Measures: Reported instruction in 7 basic science and 6 clinical science content areas (elective or required) and hours of tobacco dependence education were assessed and compared with the 1998 data.

Results: The mean (standard deviation) number of content areas reported as covered in 2010 was 10.6 (2.3) (6.1 [1.2] basic science areas, 4.6 [1.3] clinical science areas). Seventeen of 27 respondents (63%) reported that smokeless tobacco content was covered at their school, and 9 of 27 (33%) reported that the stages of change counseling technique was covered. Compared with 1998, a significant increase was noted in the percentage of schools covering tobacco dependence (92.6% in 2010 compared with 57.9% in 1998, P=.0002). Reported hours of tobacco dependence instruction were also significantly higher in 2010 compared with those in 1998 (Fisher exact test, P<.05). No statistically significant changes were found in the proportion of schools covering all 13 content areas (15.7% vs 22.2%), the proportion covering motivational interviewing in detail (26.3% vs 33.3%), or the proportion requiring curricula on smokeless tobacco (57.9% vs 59.3%).

Conclusion: Osteopathic medical school respondents reported more instruction on tobacco dependence in 2010 compared with those in 1998. However, some important basic science and clinical science content areas are not being adequately taught in US osteopathic medical schools.
Variability of the oxygen minimum zone in the tropical North Pacific during the late twentieth century
Authors: Ito Takamitsu , Deutsch Curtis
Published: October 2013

The oxygen minimum zones (OMZ) are especially sensitive to ocean deoxygenation due to the nonlinear dependence of their size on the oxygen inventory. Significant decadal variability has been observed in the extent and intensity of the tropical Pacific OMZ. Here we diagnose the physical and biogeochemical mechanisms behind the interannual and decadal variability of oxygen in the tropical Pacific thermocline using a three‐dimensional ocean biogeochemistry model that reproduces the expansion of the tropical Pacific OMZ since the 1980s. On interannual time scales, heat content and respiration rates are strongly influenced by El Niño‐Southern Oscillation cycles and the associated changes in upwelling. The resulting changes in solubility and apparent oxygen utilization tend to compensate one another, thus damping the magnitude of oxygen variability. Regional oxygen budget reveals the subtle balance between the lateral and vertical ocean circulation in controlling the physical oxygen supply to the eastern tropical Pacific. Spectral analysis shows that the tropical Pacific oxygen has a stronger variance in decadal time scales than its physical and biological drivers. Our results suggest that the physical oxygen supply and biological oxygen loss are integrated through the finite memory of thermocline waters to produce the multidecadal variability of OMZ.
Impact of water mass mixing on the biogeochemistry and microbiology of the Northeast Atlantic Deep Water
Authors: Reinthaler Thomas , Álvarez Salgado Xosé Antón , Álvarez Marta , van Aken Hendrik M. , Herndl Gerhard J.
Published: October 2013

The extent to which water mass mixing contributes to the biological activity of the dark ocean is essentially unknown. Using a multiparameter water mass analysis, we examined the impact of water mass mixing on the nutrient distribution and microbial activity of the Northeast Atlantic Deep Water (NEADW) along an 8000 km long transect extending from 62°N to 5°S. Mixing of four water types (WT) and basin scale mineralization from the site where the WT where defined to the study area explained up to 95% of the variability in the distribution of inorganic nutrients and apparent oxygen utilization. Mixing‐corrected average O2:N:P mineralization ratios of 127(±11):13.0(±0.7):1 in the core of the NEADW suggested preferential utilization of phosphorus compounds while dissolved organic carbon mineralization contributed a maximum of 20% to the oxygen demand of the NEADW. In conjunction with the calculated average mineralization ratios, our results indicate a major contribution of particulate organic matter to the biological activity in the NEADW. The variability in prokaryotic abundance, high nucleic acid containing cells, and prokaryotic heterotrophic production in the NEADW was explained by large scale (64–79%) and local mineralization processes (21–36%), consistent with the idea that deep‐water prokaryotic communities are controlled by substrate supply. Overall, our results suggest a major impact of mixing on the distribution of inorganic nutrients and a weaker influence on the dissolved organic matter pool supporting prokaryotic activity in the NEADW.
Detection of carbon monoxide trends in the presence of interannual variability
Authors: Strode Sarah A. , Pawson Steven
Published: October 2013

Trends in fossil fuel emissions are a major driver of changes in atmospheric CO, but detection of trends in CO from anthropogenic sources is complicated by the presence of large interannual variability (IAV) in biomass burning. We use a multiyear model simulation of CO with year‐specific biomass burning to predict the number of years needed to detect the impact of changes in Asian anthropogenic emissions on downwind regions. Our study includes two cases for changing anthropogenic emissions: a stepwise change of 15% and a linear trend of 3% yr−1. We first examine how well the model reproduces the observed IAV of CO over the North Pacific, since this variability impacts the time needed to detect significant anthropogenic trends. The modeled IAV over the North Pacific correlates well with that seen from the Measurements of Pollution in the Troposphere (MOPITT) instrument but underestimates the magnitude of the variability. The model predicts that a 3% yr−1 trend in Asian anthropogenic emissions would lead to a statistically significant trend in CO surface concentration in the western United States within 12 years, and accounting for Siberian boreal biomass‐burning emissions greatly reduces the number of years needed for trend detection. Combining the modeled trend with the observed MOPITT variability at 500 hPa, we estimate that the 3% yr−1 trend could be detectable in satellite observations over Asia in approximately a decade. Our predicted timescales for trend detection highlight the importance of long‐term measurements of CO from satellites.
On using the relationship between Doppler velocity and radar reflectivity to identify microphysical processes in midlatitudinal ice clouds
Authors: Kalesse Heike , Kollias Pavlos , Szyrmer Wanda
Published: October 2013

Ground‐based 35 GHz profiling Doppler cloud radar observations of ice clouds were used to derive the power law relation between Doppler velocity Vd and radar reflectivity Z (Vd = aZb). By removing the vertical air motion from Vd, the power law can be rewritten as Vt = aZb with Vt being the reflectivity‐weighted particle terminal fall velocity. Profiles of this relation are variable with height. An attempt was made to relate this variability to the dominant microphysical processes in different layers of the cloud. Based on that, the possibility of using profiles of the parameters a and b to distinguish different microphysical regimes was explored. The methodology was applied to long‐term measurements (January 1997 to December 2010) at the Atmospheric Radiation Measurement site in the Southern Great Plains. Principal component analysis was used to determine the modes of the profiles that explain most of the observed variance in the observations. Profile‐averaged means and standard deviations of parameters a and b amounted to 0.65 ± 0.42 and 0.03 ± 0.19, respectively. Furthermore, three commonly used microphysical relations related to bulk quantities were used to determine values of a and b. These results were found to compare reasonably well with the values obtained from the radar observations. Finally, microphysical considerations showed that radar‐derived values of parameter b can be explained in terms of particle size distribution moment changes.
25th Anniversary Article: CVD Polymers: A New Paradigm for Surface Modifi cation and Device Fabrication
Authors: Coclite Anna Maria , Howden Rachel M. , Borrelli David C. , Petruczok Christy D. , Yang Rong , Yagüe Jose Luis , Ugur Asli , Chen Nan , Lee Sunghwan , Jo Won Jun , Liu Andong , Wang Xiaoxue , Gleason Karen K.
Published: October 2013

Well‐adhered, conformal, thin (<100 nm) coatings can easily be obtained by chemical vapor deposition (CVD) for a variety of technological applications. Room temperature modification with functional polymers can be achieved on virtually any substrate: organic, inorganic, rigid, flexible, planar, three‐dimensional, dense, or porous. In CVD polymerization, the monomer(s) are delivered to the surface through the vapor phase and then undergo simultaneous polymerization and thin film formation. By eliminating the need to dissolve macromolecules, CVD enables insoluble polymers to be coated and prevents solvent damage to the substrate. CVD film growth proceeds from the substrate up, allowing for interfacial engineering, real‐time monitoring, and thickness control. Initiated‐CVD shows successful results in terms of rationally designed micro‐ and nanoengineered materials to control molecular interactions at material surfaces. The success of oxidative‐CVD is mainly demonstrated for the deposition of organic conducting and semiconducting polymers.
Electrophoresis of pH‐regulated particles in the presence of multiple ionic species
Authors: Hsu Chien , Lee Duu‐Jong , Hsu Jyh‐Ping , Wang Nan , Tseng Shiojenn
Published: October 2013

An electrophoresis model taking account of the pH‐regulated nature of particles and the presence of multiple ionic species is proposed for arbitrary surface potential and double‐layer thickness. It successfully simulated the electrophoretic behavior of Fe3O4 nanoparticles in an aqueous NaCl solution with pH adjusted by HCl and NaOH. The estimated zeta potential is compared with those from the conventional models, Smoluchowski's, Hückel's, and Henry's formulas. Due to the violation of the assumption of low and constant surface potential, these formulas yielded appreciable deviations (e.g., 23–30 mV at pH 9). With the surface charge density measured by titration and the zeta potential by electrophoresis, the true surface potential is estimated through a triple‐layer model. The estimated true potential is typically 1.5–10 times larger than the zeta potential, implying that using the latter in relevant calculations (e.g., stability and critical coagulation concentration) might yield appreciable deviation. © 2013 American Institute of Chemical Engineers AIChE J 60: 451–458, 2014