WorldWideScience

Sample records for replace metallic parts

  1. The tribology of metal-on-metal total hip replacements.

    Science.gov (United States)

    Scholes, S C; Unsworth, A

    2006-02-01

    Total hip surgery is an effective way of alleviating the pain and discomfort caused by diseased or damaged joints. However, in the majority of cases, these joints have a finite life. The main reason for failure is osteolysis (bone resorption). It is well documented that an important cause of osteolysis, and therefore the subsequent loosening and failure of conventional metal- or ceramic-on-ultra-high molecular weight polyethylene joints, is the body's immunological response to the polyethylene wear particles. To avoid this, interest has been renewed in metal-on-metal joints. The intention of this paper is to review the studies that have taken place within different laboratories to determine the tribological performance of new-generation metal-on-metal total hip replacements. These types of joint offer a potential solution to enhance the longevity of prosthetic hip systems; however, problems may arise owing to the effects of metal ion release, which are, as yet, not fully understood.

  2. Replacement of metal hinged shaft on upper part of stacker/reclaimer%堆取料机上部金属结构铰轴更换工艺

    Institute of Scientific and Technical Information of China (English)

    梁业

    2012-01-01

    Aiming at the abnormal sound of the metal hinged shaft on the upper part of stacker/reclaimer, the paper proposes the corresponding solutions, and details the replacement process of hinged shaft by using repair frame, with which construction period can be shortened about three days compared with the scheme of making the intersecting support.%针对斗轮堆取料机上部金属结构铰轴出现异响问题,提出解决方案,详细介绍了利用维修架进行铰轴更换的工艺,比制作井字架支撑的施工方案缩短工期约3天.

  3. Novel Amalgams for In-Space Fabrication of Replacement Parts

    Science.gov (United States)

    Cochran, Calvin T.; Van Hoose, James R.; Grugel, R. N.

    2012-01-01

    Being able to fabricate replacement parts during extended space flight missions precludes the weight, storage volume, and speculation necessary to accommodate spares. Amalgams, widely used in dentistry, are potential candidates for fabricating parts in microgravity environments as they are moldable, do not require energy for melting, and do not pose fluid handling problems. Unfortunately, amalgams have poor tensile strength and the room temperature liquid component is mercury. To possibly resolve these issues a gallium-indium alloy was substituted for mercury and small steel fibers were mixed in with the commercial alloy powder. Subsequent microscopic examination of the novel amalgam revealed complete bonding of the components, and mechanical testing of comparable samples showed those containing steel fibers to have a significant improvement in strength. Experimental procedures, microstructures, and test results are presented and discussed in view of further improving properties.

  4. Replaceable Substructures for Efficient Part-Based Modeling

    KAUST Repository

    Liu, Han

    2015-05-01

    A popular mode of shape synthesis involves mixing and matching parts from different objects to form a coherent whole. The key challenge is to efficiently synthesize shape variations that are plausible, both locally and globally. A major obstacle is to assemble the objects with local consistency, i.e., all the connections between parts are valid with no dangling open connections. The combinatorial complexity of this problem limits existing methods in geometric and/or topological variations of the synthesized models. In this work, we introduce replaceable substructures as arrangements of parts that can be interchanged while ensuring boundary consistency. The consistency information is extracted from part labels and connections in the original source models. We present a polynomial time algorithm that discovers such substructures by working on a dual of the original shape graph that encodes inter-part connectivity. We demonstrate the algorithm on a range of test examples producing plausible shape variations, both from a geometric and from a topological viewpoint. © 2015 The Author(s) Computer Graphics Forum © 2015 The Eurographics Association and John Wiley & Sons Ltd. Published by John Wiley & Sons Ltd.

  5. Using your shoulder after replacement surgery

    Science.gov (United States)

    Joint replacement surgery - using your shoulder; Shoulder replacement surgery - after ... You have had shoulder replacement surgery to replace the bones of your shoulder joint with artificial parts. The parts include a stem made of metal and a ...

  6. Metallic parts fabrication using the SIS process

    Science.gov (United States)

    Mojdeh, Mehdi

    Since early 1980s, quite a few techniques of Rapid Prototyping (RP), also known as Layered Manufacturing, have been developed. By building three-dimensional parts in a layer-by-layer additive manner, these techniques allow freeform fabrication of parts of complex geometry. Despite recent advances in fabrication of polymer parts, most of the existing rapid prototyping processes are still not capable of fabrication of accurate metallic parts with acceptable mechanical properties. Insufficient dimensional accuracy, limited number of materials, proper mechanical properties, required post machining and lack of repeatability between builds have greatly limited the market penetration of these techniques. This dissertation presents an innovative layered manufacturing technique for fabrication of dense metallic parts called Selective Inhibition Sintering (SIS), developed at the University of Southern California. The SIS-Metal technology adapts RP capabilities and extends them to the field of fabrication of metallic parts for a variety of applications such as tooling and low volume production. Using this process, a metallic part, with varying 3 dimensional geometries, can be automatically constructed from a wide range of materials. SIS-Metal is the only RP process which is suitable for fabrication of dense, complex shaped, accurate objects using a variety of materials. In the SIS-Metal process a metallic part is built layer by layer by deposition for each layer of an inhibitor material which defines the corresponding layer boundary and then filling the voids of the created geometry with metal powder; and compacting the layer formed to reach a high powder density. The resulting green part is then sintered in a furnace to yield the final functional part. In this research different inhibition techniques were explored and a series of single and multi layer parts was fabricated using the most promising inhibition technique, namely, macro-mechanical inhibition. Dimensional

  7. Balancing innovation and medical device regulation: the case of modern metal-on-metal hip replacements

    Science.gov (United States)

    Howard, Jason J

    2016-01-01

    Due to problems with wear particle generation and subsequent loosening using conventional metal-on-polyethylene total hip replacements, there has been a shift toward alternative bearing systems, including metal-on-metal (MoM), for younger, more active patients with degenerative joint disease. Based on positive results from early short-term clinical studies, MoM hip replacements were readily adopted by orthopedic surgeons with thousands being implanted worldwide over the past decade. Unacceptably high revision rates reported by two national joint registries called into question the rigorousness of the regulatory approval process for these implants, particularly with respect to premarket data requirements to prove safety, effectiveness, and the appropriateness of the regulatory pathway chosen. The purpose of this review was to investigate the balance between facilitating the introduction of new medical technologies and the need to ensure safety and effectiveness through comprehensive regulatory assessment. The case of MoM hip replacement devices was used to frame the investigation and subsequent discussions. The regulatory approval processes and post-market surveillance requirements associated with three common MoM hip replacements (two resurfacings: the Birmingham and articular surface replacement and the articular surface replacement XL total hip replacement) were investigated. With respect to modern MoM hip replacement devices, the balance between facilitating the introduction of these new medical technologies and the need to ensure safety and effectiveness through comprehensive regulatory assessment was not achieved. The lessons learned from these experiences have application beyond joint replacements to the introduction of new medical technologies in general, particularly for those who have a significant potential for harm. In this regard, a series of recommendations have been developed to contribute to the evolution of the medical device regulatory process

  8. Balancing innovation and medical device regulation: the case of modern metal-on-metal hip replacements

    Directory of Open Access Journals (Sweden)

    Howard JJ

    2016-08-01

    Full Text Available Jason J Howard1,2 1Division of Orthopedic Surgery, Department of Surgery, Sidra Medical and Research Center, 2Department of Orthopedic Surgery, Weill Cornell Medical College, Doha, Qatar Abstract: Due to problems with wear particle generation and subsequent loosening using conventional metal-on-polyethylene total hip replacements, there has been a shift toward alternative bearing systems, including metal-on-metal (MoM, for younger, more active patients with degenerative joint disease. Based on positive results from early short-term clinical studies, MoM hip replacements were readily adopted by orthopedic surgeons with thousands being implanted worldwide over the past decade. Unacceptably high revision rates reported by two national joint registries called into question the rigorousness of the regulatory approval process for these implants, particularly with respect to premarket data requirements to prove safety, effectiveness, and the appropriateness of the regulatory pathway chosen. The purpose of this review was to investigate the balance between facilitating the introduction of new medical technologies and the need to ensure safety and effectiveness through comprehensive regulatory assessment. The case of MoM hip replacement devices was used to frame the investigation and subsequent discussions. The regulatory approval processes and post-market surveillance requirements associated with three common MoM hip replacements (two resurfacings: the Birmingham and articular surface replacement and the articular surface replacement XL total hip replacement were investigated. With respect to modern MoM hip replacement devices, the balance between facilitating the introduction of these new medical technologies and the need to ensure safety and effectiveness through comprehensive regulatory assessment was not achieved. The lessons learned from these experiences have application beyond joint replacements to the introduction of new medical technologies in

  9. REVIEW ABOUT METAL PARTS RECONDITIONING

    Directory of Open Access Journals (Sweden)

    DAN FLORIN NITOI

    2015-05-01

    Full Text Available Paper realize a presentation of different deposition methods starting with the definition of this procedure including all the advantages and disadvantages. It is presented the welding technology with its different methods, the metalization method, all in order to choose the proper technology for different reconditioning situations in industry.

  10. Corrosion on the acetabular liner taper from retrieved modular metal-on-metal total hip replacements.

    Science.gov (United States)

    Gascoyne, Trevor C; Dyrkacz, Richard M; Turgeon, Thomas R; Burnell, Colin D; Wyss, Urs P; Brandt, Jan-M

    2014-10-01

    Eight retrieved metal-on-metal total hip replacements displayed corrosion damage along the cobalt-chromium alloy liner taper junction with the Ti alloy acetabular shell. Scanning electron microscopy indicated the primary mechanism of corrosion to be grain boundary and associated crevice corrosion, which was likely accelerated through mechanical micromotion and galvanic corrosion resulting from dissimilar alloys. Coordinate measurements revealed up to 4.3mm(3) of the cobalt-chromium alloy taper surface was removed due to corrosion, which is comparable to previous reports of corrosion damage on head-neck tapers. The acetabular liner-shell taper appears to be an additional source of metal corrosion products in modular total hip replacements. Patients with these prostheses should be closely monitored for signs of adverse reaction towards corrosion by-products.

  11. Metal on metal hip resurfacing versus uncemented custom total hip replacement - early results

    Directory of Open Access Journals (Sweden)

    Muirhead-Allwood Sarah K

    2010-02-01

    Full Text Available Abstract Introduction There is no current consensus on the most appropriate prosthesis for treating symptomatic osteoarthritis (OA of the hip in young, active patients. Modern metal on metal hip resurfacing arthroplasty (HR has gained popularity as it is theoretically more stable, bone conserving and easier to revise than total hip arthroplasty. Early results of metal on metal resurfacing have been encouraging. We have compared two well matched cohorts of patients with regard to function, pain relief and patient satisfaction. Methods This prospective study compares 2 cohorts of young, active patients treated with hip resurfacing (137 patients, 141 hips and custom uncemented (CADCAM stems (134 patients, 141 hips. All procedures were performed by a single surgeon. Outcome measures included Oxford, WOMAC and Harris hip scores as well as an activity score. Statistical analysis was performed using the unpaired student's t-test. Results One hundred and thirty four and 137 patients were included in the hip replacement and resurfacing groups respectively. The mean age of these patients was 54.6 years. The mean duration of follow up for the hip resurfacing group was 19.2 months compared to 13.4 months for the total hip replacement group. Pre operative oxford, Harris and WOMAC scores in the THA group were 41.1, 46.4 and 50.9 respectively while the post operative scores were 14.8, 95.8 and 5.0. In the HR group, pre- operative scores were 37.0, 54.1 and 45.9 respectively compared to 15.0, 96.8 and 6.1 post operatively. The degree of improvement was similar in both groups. Conclusion There was no significant clinical difference between the patients treated with hip resurfacing and total hip arthroplasty in the short term.

  12. Replacement

    Directory of Open Access Journals (Sweden)

    S. Radhakrishnan

    2014-03-01

    Full Text Available The fishmeal replaced with Spirulina platensis, Chlorella vulgaris and Azolla pinnata and the formulated diet fed to Macrobrachium rosenbergii postlarvae to assess the enhancement ability of non-enzymatic antioxidants (vitamin C and E, enzymatic antioxidants (superoxide dismutase (SOD and catalase (CAT and lipid peroxidation (LPx were analysed. In the present study, the S. platensis, C. vulgaris and A. pinnata inclusion diet fed groups had significant (P < 0.05 improvement in the levels of vitamins C and E in the hepatopancreas and muscle tissue. Among all the diets, the replacement materials in 50% incorporated feed fed groups showed better performance when compared with the control group in non-enzymatic antioxidant activity. The 50% fishmeal replacement (best performance diet fed groups taken for enzymatic antioxidant study, in SOD, CAT and LPx showed no significant increases when compared with the control group. Hence, the present results revealed that the formulated feed enhanced the vitamins C and E, the result of decreased level of enzymatic antioxidants (SOD, CAT and LPx revealed that these feeds are non-toxic and do not produce any stress to postlarvae. These ingredients can be used as an alternative protein source for sustainable Macrobrachium culture.

  13. Histological characterization of periprosthetic tissue responses for metal-on-metal hip replacement.

    Science.gov (United States)

    Phillips, Eual A; Klein, Gregg R; Cates, Harold E; Kurtz, Steven M; Steinbeck, Marla

    2014-01-01

    The histology of periprosthetic tissue from metal-on-metal (MOM) hip devices has been characterized using a variety of methods. The purpose of this study was to compare and evaluate the suitability of two previously developed aseptic lymphocyte-dominated vasculitis-associated lesions (ALVAL) scoring systems for periprosthetic hip tissue responses retrieved from MOM total hip replacement (THR) systems revised for loosening. Two ALVAL scoring systems (Campbell and Oxford) were used to perform histological analyses of soft tissues from 17 failed MOM THRs. The predominant reactions for this patient cohort were macrophage infiltration and necrosis, with less than half of the patients (41%) showing a significant lymphocytic response or a high ALVAL reaction (6%). Other morphological changes varied among patients and included hemosiderin accumulation, cartilage formation, and heterotopic ossification. Both scoring systems are useful for correlating macrophage and lymphocyte responses and for comparison with the other; however, given the diversity and variability of the current responses, the Oxford-ALVAL system is more suitable for scoring tissues from MOM THR patients revised for loosening. It is important that standardized methods of scoring MOM tissue responses be used consistently so multiple study results can be compared and a consensus can be generated.

  14. Development of Replacements for Phoscoating Used in Forging, Extrusion and Metal Forming Processes

    Energy Technology Data Exchange (ETDEWEB)

    Kerry Barnett

    2003-03-01

    Many forging, extrusion, heading and other metal forming processes use graphite-based lubricants, phosphate coatings, and other potentially hazardous or harmful substances to improve the tribology of the metal forming process. The application of phosphate-based coatings has long been studied to determine if other synthetic ''clean'' lubricants could provide the same degree of protection afforded by phoscoatings and its formulations. So far, none meets the cost and performance objectives provided by phoscoatings as a general aid to the metal forming industry. In as much as phoscoatings and graphite have replaced lead-based lubricants, the metal forming industry has had previous experience with a legislated requirement to change processes. However, without a proactive approach to phoscoating replacement, many metal forming processes could find themselves without a cost effective tribology material necessary for the metal forming process

  15. ET Toxic Metals Replacement Review SEA Spring Face to Face

    Science.gov (United States)

    Pratz, Earl

    2007-01-01

    The information contained in the presentation covers development work carried out under SDS projects. The intent of the effort is to find chrome(VI) free alternates to our current chromated processing solutions. The information presented reports progress in work aimed to replace our alkaline cleaner (Turco 4215), conversion coat (Iridite 14-2) and chrome (VI) compounds used in LOx tank hydrostatic proof test solution. To date we have found candidates for use in the proof test solution and alkaline cleaner. These candidates are in the final stages of testing. Lab data is reported in the presentation.

  16. An opposite view data replacement approach for reducing artifacts due to metallic dental objects

    Energy Technology Data Exchange (ETDEWEB)

    Yazdi, Mehran; Lari, Meghdad Asadi; Bernier, Gaston; Beaulieu, Luc [Department of Electrical Engineering, School of Engineering, Shiraz University, Shiraz 7134851154 (Iran, Islamic Republic of) and Departement de Radio-Oncologie, Ho circumflex tel-Dieu de Quebec, Centre Hospitalier Universitaire de Quebec, 11 Cote du Palais, Quebec, Quebec G1R 2J6 (Canada); Department of Electrical Engineering, School of Engineering, Shiraz University, Shiraz 7134851154 (Iran, Islamic Republic of); Departement de Radio-Oncologie, Ho circumflex tel-Dieu de Quebec, Centre Hospitalier Universitaire de Quebec, 11 Cote du Palais, Quebec, Quebec G1R 2J6 (Canada); Departement de Physique, de Genie Physique et D' optique, Universite Laval, Quebec, Quebec (Canada) and Departement de Radio-Oncologie, Hotel-Dieu de Quebec, Centre Hospitalier Universitaire de Quebec, 11 Cote du Palais, Quebec, Quebec G1R 2J6 (Canada)

    2011-04-15

    Purpose: To present a conceptually new method for metal artifact reduction (MAR) that can be used on patients with multiple objects within the scan plane that are also of small sized along the longitudinal (scanning) direction, such as dental fillings. Methods: The proposed algorithm, named opposite view replacement, achieves MAR by first detecting the projection data affected by metal objects and then replacing the affected projections by the corresponding opposite view projections, which are not affected by metal objects. The authors also applied a fading process to avoid producing any discontinuities in the boundary of the affected projection areas in the sinogram. A skull phantom with and without a variety of dental metal inserts was made to extract the performance metric of the algorithm. A head and neck case, typical of IMRT planning, was also tested. Results: The reconstructed CT images based on this new replacement scheme show a significant improvement in image quality for patients with metallic dental objects compared to the MAR algorithms based on the interpolation scheme. For the phantom, the authors showed that the artifact reduction algorithm can efficiently recover the CT numbers in the area next to the metallic objects. Conclusions: The authors presented a new and efficient method for artifact reduction due to multiple small metallic objects. The obtained results from phantoms and clinical cases fully validate the proposed approach.

  17. Reaction kinetics of metal deposition via surface limited red-ox replacement of underpotentially deposited metal monolayers

    Energy Technology Data Exchange (ETDEWEB)

    Gokcen, Dincer; Bae, Sang-Eun [Electrical and Computer Engineering, University of Houston, Houston, TX 772004-4005 (United States); Brankovic, Stanko R., E-mail: Stanko.Brankovic@mail.uh.edu [Electrical and Computer Engineering, University of Houston, Houston, TX 772004-4005 (United States); Chemical and Biomolecular Engineering, University of Houston, Houston, TX 772004-4005 (United States); Chemistry Department, University of Houston, Houston, TX 772004-4005 (United States)

    2011-06-30

    The study of the kinetics of metal deposition via surface limited red-ox replacement of underpotentially deposited metal monolayers is presented. The model system was Pt submonolayer deposition on Au(1 1 1) via red-ox replacement of Pb and Cu UPD monolayers on Au(1 1 1). The kinetics of a single replacement reaction was studied using the formalism of the comprehensive analytical model developed to fit the open circuit potential transients from deposition experiments. The practical reaction kinetics parameters like reaction half life, reaction order and reaction rate constant are determined and discussed with their relevance to design and control of deposition experiments. The effects of transport limitation and the role of the anions/electrolyte on deposition kinetics are investigated and their significance to design of effective deposition process is discussed.

  18. Complete replacement of metal in metal oxide nanowires via atomic diffusion: In/ZnO case study.

    Science.gov (United States)

    Wang, Shau-Chieh; Lu, Ming-Yen; Manekkathodi, Afsal; Liu, Pei-Hsuan; Lin, Hung-Chiao; Li, Wun-Shan; Hou, Te-Chien; Gwo, Shangjr; Chen, Lih-Juann

    2014-06-11

    Atomic diffusion is a fundamental process that dictates material science and engineering. Direct visualization of atomic diffusion process in ultrahigh vacuum in situ TEM could comprehend the fundamental information about metal-semiconductor interface dynamics, phase transitions, and different nanostructure growth phenomenon. Here, we demonstrate the in situ TEM observations of the complete replacement of ZnO nanowire by indium with different growth directions. In situ TEM analyses reveal that the diffusion processes strongly depend and are dominated by the interface dynamics between indium and ZnO. The diffusion exhibited a distinct ledge migration by surface diffusion at [001]-ZnO while continuous migration with slight/no ledges by inner diffusion at [100]-ZnO. The process is explained based on thermodynamic evaluation and growth kinetics. The results present the potential possibilities to completely replace metal-oxide semiconductors with metal nanowires without oxidation and form crystalline metal nanowires with precise epitaxial metal-semiconductor atomic interface. Formation of such single crystalline metal nanowire without oxidation by diffusion to the metal oxide is unique and is crucial in nanodevice performances, which is rather challenging from a manufacturing perspective of 1D nanodevices.

  19. Changes in the periodontal condition after replacement of swaged crowns by metal.

    Science.gov (United States)

    Plotniece-Baranovska, Anita; Soboleva, Una; Rogovska, Irena; Apse, Peteris

    2006-01-01

    Evidence based clinical studies have shown exact recommended design for artificial crown reconstruction with acceptable long-term results taking into an account the biological price. Previous histological and clinical studies proved that fixed prostheses might influence the periodontal condition of crowned teeth, if not all biological criteria have been considered. The aim of the present study was to assess the periodontal condition of the crowned teeth after stainless steel swaged crowns were replaced by cast metal ceramic crowns. Participants were selected at the Institute of Stomatology, Stradin's University. Selection criteria included need to replace existing swaged crowns by metal ceramic crowns for patients with absence of any systemic disease. Following symptoms of periodontal condition were examined - presence of inflammation (clinical signs, probing) and pocket depth. Assessments were carried out at four different points of time (first appointment after replacement existing swaged crowns by temporary crowns; two weeks after cementation of permanent metal ceramic restoration; after three month; after six month). Overall bleeding score "2" and "3" at the first measurement was observed in majority of study population. Bleeding scores between the 1st and the 4th measurement was significantly lower (pcrowns by metal ceramic improves gingival health and leads to better long-term prognosis for restored teeth. It is recommended that swaged crowns be replaced with more biologically friendly crowns.

  20. 49 CFR Appendix A to Part 564 - Information To Be Submitted for Replaceable Light Sources

    Science.gov (United States)

    2010-10-01

    ... information required by paragraphs A, B, and C of this section I for light sources using a resistive type... 49 Transportation 6 2010-10-01 2010-10-01 false Information To Be Submitted for Replaceable Light Sources A Appendix A to Part 564 Transportation Other Regulations Relating to Transportation (Continued...

  1. 18 CFR Appendix A to Part 2 - Guidance for Determining the Acceptable Construction Area for Replacements

    Science.gov (United States)

    2010-04-01

    ... 18 Conservation of Power and Water Resources 1 2010-04-01 2010-04-01 false Guidance for Determining the Acceptable Construction Area for Replacements A Appendix A to Part 2 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION, DEPARTMENT OF ENERGY GENERAL RULES GENERAL...

  2. REPLACEMENT SPARE PART INVENTORY MONITORING USING ADAPTIVE NEURO FUZZY INFERENCE SYSTEM

    Directory of Open Access Journals (Sweden)

    Hartono Hartono

    2016-01-01

    Full Text Available Abstract   The amount of inventory is determined on the basis of the demand. So that users can know the demand forecasts need to be done on the request. This study uses the data to implement a replacement parts on the electronic module production equipment in the telecommunications transmission systems, switching, access and power, ie by replacing the electronic module in the system is trouble  or damaged parts of a good electronic module spare parts inventory, while the faulty electronic modules shipped to the Repair Center for repaired again, so that the results of these improvements can replenish spare part  inventory. Parameters speed on improvement process of electronic module broken (repaired, in the form of an average repair time at the repair centers, in order to get back into the electronic module that is ready for used as spare parts in compliance with the safe supply inventory  warehouse.  This research using the method  of  Adaptive Neuro Fuzzy Inference System (ANFIS in developing a decision support system for inventory control of spare parts available in Warehouse Inventory taking into account several parameters supporters, namely demand, improvement and fulfillment of spare parts and repair time. This study uses a recycling input parameter repair faulty electronic module of the customer to immediately replace the module in inventory warehouse,  do improvements in the Repair Center. So the acceleration restoration factor is very influential as the input spare parts inventory supply in the warehouse and using the Adaptive Neuro-Fuzzy Inference System (ANFIS method.   Keywords: ANFIS, inventory control, replacement

  3. Electrophoretic deposition of organic/inorganic composite coatings on metallic substrates for bone replacement applications: mechanisms and development of new bioactive materials based on polysaccharides

    OpenAIRE

    Cordero Arias, Luis Eduardo

    2015-01-01

    Regarding the need to improve the usually encountered osteointegration of metallic implants with the surrounding body tissue in bone replacement applications, bioactive organic/inorganic composite coatings on metallic substrates were developed in this work using electrophoretic deposition (EPD) as coating technology. In the present work three polysaccharides, namely alginate, chondroitin sulfate and chitosan were used as the organic part, acting as the matrix of the coating and enabling the c...

  4. Manufacturing processes of cellular metals. Part II. Solid route, metals deposition, other processes; Procesos de fabricacion de metales celulares. Parte II: Via solida, deposicion de metales otros procesos

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez, P.; Cruz, L. J.; Coleto, J.

    2009-07-01

    At the first part of this paper review a description about cellular metal processes by liquid route, was made. In this second part, solid processes and metals deposition are described. In similar way, the different kind of processes in each case are reviewed; making a short description about the main parameters involved and the advantages and drawbacks in each of them. (Author) 147 refs.

  5. HEAVY METALS IN PRODUCTIVE PARTS OF AGRICULTURAL PLANTS

    Directory of Open Access Journals (Sweden)

    Július Árvay

    2012-02-01

    Full Text Available The contents of heavy metals in plants were not in relation to contents of heavy metals in soil. Increased content of heavy metals in soils was not in consistency with content in plants. Usually content of heavy metals in plants according to our results were lower than their content in soil. Only the over limit contents of copper and cadmium were assessed in grain of barley and oat. The results of heavy metals content showed that dominant part on content of elements in plants have their mobile forms what depends on pH, content of organic matter in soil and portion of clay parts.

  6. Retrieval analysis of 240 metal-on-metal hip components, comparing modular total hip replacement with hip resurfacing.

    Science.gov (United States)

    Matthies, A; Underwood, R; Cann, P; Ilo, K; Nawaz, Z; Skinner, J; Hart, A J

    2011-03-01

    This study compared component wear rates and pre-revision blood metal ions levels in two groups of failed metal-on-metal hip arthroplasties: hip resurfacing and modular total hip replacement (THR). There was no significant difference in the median rate of linear wear between the groups for both acetabular (p = 0.4633) and femoral (p = 0.0872) components. There was also no significant difference in the median linear wear rates when failed hip resurfacing and modular THR hips of the same type (ASR and Birmingham hip resurfacing (BHR)) were compared. Unlike other studies of well-functioning hips, there was no significant difference in pre-revision blood metal ion levels between hip resurfacing and modular THR. Edge loading was common in both groups, but more common in the resurfacing group (67%) than in the modular group (57%). However, this was not significant (p = 0.3479). We attribute this difference to retention of the neck in resurfacing of the hip, leading to impingement-type edge loading. This was supported by visual evidence of impingement on the femur. These findings show that failed metal-on-metal hip resurfacing and modular THRs have similar component wear rates and are both associated with raised pre-revision blood levels of metal ions.

  7. USING TRABECULAR METAL AUGMENTS FOR TOTAL HIP REPLACEMENT IN PATIENTS AFTER ACETABULAR FRACTURES

    Directory of Open Access Journals (Sweden)

    R. M. Tikhilov

    2011-01-01

    Full Text Available The authors presented the experience of treatment of two patients with hip arthritis after acetabular fracture. Both patients were treated with total hip replacement. During the operation, to manage posterior-superior bone defects of the acetabulum, augments of trabecular metal were used. Pain and limitation of motions in hip were indications for operative treatment. After a year of follow up there was no pain in hip; also recovery of motion and improved quality of life were observed.

  8. Metal release and metal allergy after total hip replacement with resurfacing versus conventional hybrid prosthesis

    DEFF Research Database (Denmark)

    Gustafson, Klas; Jakobsen, Stig Storgaard; Lorenzen, Nina D

    2014-01-01

    to an increased incidence of metal allergy. METHODS: 52 hips in 52 patients (median age 60 (51-64) years, 30 women) were randomized to either a MOM hip resurfacing system (ReCap) or a standard MOP total hip arthoplasty (Mallory Head/Exeter). Spot urine samples were collected preoperatively, postoperatively, after....... RESULTS: A statistically significant 10- to 20-fold increase in urinary levels of cobalt and chromium was observed throughout the entire follow-up in the MOM group. The prevalence of metal allergy was similar between groups. INTERPRETATION: While we observed significantly increased levels of metal ions...

  9. Additive Manufacturing: Reproducibility of Metallic Parts

    Directory of Open Access Journals (Sweden)

    Konda Gokuldoss Prashanth

    2017-02-01

    Full Text Available The present study deals with the properties of five different metals/alloys (Al-12Si, Cu-10Sn and 316L—face centered cubic structure, CoCrMo and commercially pure Ti (CP-Ti—hexagonal closed packed structure fabricated by selective laser melting. The room temperature tensile properties of Al-12Si samples show good consistency in results within the experimental errors. Similar reproducible results were observed for sliding wear and corrosion experiments. The other metal/alloy systems also show repeatable tensile properties, with the tensile curves overlapping until the yield point. The curves may then follow the same path or show a marginal deviation (~10 MPa until they reach the ultimate tensile strength and a negligible difference in ductility levels (of ~0.3% is observed between the samples. The results show that selective laser melting is a reliable fabrication method to produce metallic materials with consistent and reproducible properties.

  10. Defectivity control of aluminum chemical mechanical planarization in replacement metal gate process of MOSFET

    Science.gov (United States)

    Jin, Zhang; Yuling, Liu; Chenqi, Yan; Yangang, He; Baohong, Gao

    2016-04-01

    The replacement metal gate (RMG) defectivity performance control is very challenging in high-k metal gate (HKMG) chemical mechanical polishing (CMP). In this study, three major defect types, including fall-on particles, micro-scratch and corrosion have been investigated. The research studied the effects of polishing pad, pressure, rotating speed, flow rate and post-CMP cleaning on the three kinds of defect, which finally eliminated the defects and achieved good surface morphology. This study will provide an important reference value for the future research of aluminum metal gate CMP. Project supported by the Major National Science and Technology Special Projects (No. 2009ZX02308), the Natural Science Foundation for the Youth of Hebei Province (Nos. F2012202094, F2015202267), and the Outstanding Youth Science and Technology Innovation Fund of Hebei University of Technology (No. 2013010).

  11. HEAVY METALS IN PRODUCTIVE PARTS OF AGRICULTURAL PLANTS

    OpenAIRE

    Július Árvay; Ján Tomáš; Tomáš Tóth

    2012-01-01

    The contents of heavy metals in plants were not in relation to contents of heavy metals in soil. Increased content of heavy metals in soils was not in consistency with content in plants. Usually content of heavy metals in plants according to our results were lower than their content in soil. Only the over limit contents of copper and cadmium were assessed in grain of barley and oat. The results of heavy metals content showed that dominant part on content of elements in plants have their mobil...

  12. Lactose in milk replacer can partly be replaced by glucose, fructose, or glycerol without affecting insulin sensitivity in veal calves

    NARCIS (Netherlands)

    Pantophlet, A. J.; Gilbert, M. S.; van den Borne, J. J. G. C.; Gerrits, W. J. J.; Roelofsen, H.; Priebe, M. G.; Vonk, R. J.

    Calf milk replacer (MR) contains 40 to 50% lactose. Lactose strongly fluctuates in price and alternatives are desired. Also, problems with glucose homeostasis and insulin sensitivity (i.e., high incidence of hyperglycemia and hyperinsulinemia) have been described for heavy veal calves (body weight

  13. Method for the location of primary wear scars from retrieved metal on metal hip replacements.

    Science.gov (United States)

    Govind, Garima; Henckel, Johann; Hothi, Harry; Sabah, Shiraz; Skinner, John; Hart, Alister

    2015-07-30

    Retrieved metal-on-metal acetabular cups are valuable resources in investigating the wear behaviour of failed hip implants, but adequate methods to do so are lacking. To further contribute to addressing this issue, we developed a method to detect the in vivo location of the primary wear scar of an explanted cup. We proposed a new method in which thirteen patients with failed metal hip resurfacings were recruited, and their acetabular components retrieved. A 3D wear map was generated and the precise location of the primary wear scar in each cup was identified using a coordinate measuring machine. This wear scar location was noted in relation to the features on the acetabular cup. Having identified the location of the wear scar, this 3D positional map was co-registered to the implant on the patient's pelvic 3D CT scan. Using our proposed technique, we were able to demonstrate that the in vivo position of the primary wear scar in explanted metal acetabular cups can be variable. This method has utilised existing techniques to better understand the three-dimensional properties of wear behaviour, and may be a method which can be used in further studies to investigate variables that affect the position of the primary wear scar.

  14. Comparison of discharge silver concentrations from electrolytic plating and metallic replacement silver recovery units.

    Science.gov (United States)

    Harper, Martin; Siegel, Julie M

    2003-04-01

    Silver-based photographic X-ray film is made of solid crystals of silver chloride or silver bromide suspended in a gelatin and then coated on a film. During the X-ray developing process, the image is processed and the nonimage areas containing solid silver chloride or silver bromide crystals are removed in a solution called the fixer. There may be local environmental regulations that regulate the amount of silver discharged from a facility. To meet these regulations, many facilities have added silver recovery units to their processes. Two different types of recovery processes are in use in a large hospital and three clinics under study. All of the units were claimed by their respective manufacturers to be able to recover silver down to concentrations of 5 mg/L. This concentration would ensure that the building that houses each unit would meet the local county limit of 0.5 mg/L silver for total building silver discharge. The hypothesis for this research is that one system, newer and more expensive, consisting of so-called electrolytic plating units (EPUs) (which are followed by so-called metallic replacement units [MRUs] as a backup), will have better silver recovery than MRUs alone. A total of six units were sampled, three EPUs (in combination with MRUs) and three MRUs. The units were sampled once or twice a day for 10 days for a total of 17 samples from each. The samples then were analyzed by inductively coupled plasma spectroscopy, and an analysis of variance was performed on the results. The range for the electrolytic plating unit/metallic replacement unit combinations was 0.20-99.9 mg/L (mean of 35.15 mg/L; median of 33.8 mg/L). The range for the MRUs alone was 7.2-1112 mg/L (mean of 565.5 mg/L; median of 720 mg/L). Many individual results exceeded 5 mg/L, such that extensive dilution would be required to ensure the building effluent did not exceed 0.5 mg/L. It is suggested that the metallic replacement units be changed to EPUs (with metallic replacement backup

  15. Comparison of in vivo and simulator-retrieved metal-on-metal cervical disc replacements

    Science.gov (United States)

    Kurtz, Steven M.; Ciccarelli, Lauren; Harper, Megan L.; Siskey, Ryan; Shorez, Jacob; Chan, Frank W.

    2012-01-01

    Background Cervical disc arthroplasty is regarded as a promising treatment for myelopathy and radiculopathy as an alternative to cervical spine fusion. On the basis of 2-year clinical data for the PRESTIGE® Cervical Disc (Medtronic, Memphis, Tennessee), the Food and Drug Administration recommended conditional approval in September 2006 and final approval in July 2007; however, relatively little is known about its wear and damage modes in vivo. The main objective was to analyze the tribological findings of the PRESTIGE® Cervical Disc. This study characterized the in vivo wear patterns of retrieved cervical discs and tested the hypothesis that the total disc replacements exhibited similar surface morphology and wear patterns in vitro as in vivo. Methods Ten explanted total disc replacements (PRESTIGE®, PRESTIGE® I, and PRESTIGE® II) from 10 patients retrieved after a mean of 1.8 years (range, 0.3–4.1 years) were analyzed. Wear testing included coupled lateral bending ( ±4.7°) and axial rotation ( ±3.8°) with a 49 N axial load for 5 million cycles followed by 10 million cycles of flexion-extension ( ±9.7°) with 148 N. Implant surfaces were characterized by the use of white-light interferometry, scanning electron microscopy, and energy dispersive spectroscopy. Results The explants generally exhibited a slightly discolored, elliptic wear region of varying dimension centered in the bearing center, with the long axis oriented in the medial-lateral direction. Abrasive wear was the dominant in vivo wear mechanism, with microscopic scratches generally oriented in the medial-lateral direction. Wear testing resulted in severe abrasive wear in a curvilinear fashion oriented primarily in the medial-lateral direction. All retrievals showed evidence of an abrasive wear mechanism. Conclusions This study documented important similarity between the wear mechanisms of components tested in vitro and explanted PRESTIGE® Cervical Discs; however, the severity of wear was

  16. Lactose in milk replacer can partly be replaced by glucose, fructose, or glycerol without affecting insulin sensitivity in veal calves.

    Science.gov (United States)

    Pantophlet, A J; Gilbert, M S; van den Borne, J J G C; Gerrits, W J J; Roelofsen, H; Priebe, M G; Vonk, R J

    2016-04-01

    Calf milk replacer (MR) contains 40 to 50% lactose. Lactose strongly fluctuates in price and alternatives are desired. Also, problems with glucose homeostasis and insulin sensitivity (i.e., high incidence of hyperglycemia and hyperinsulinemia) have been described for heavy veal calves (body weight >100 kg). Replacement of lactose by other dietary substrates can be economically attractive, and may also positively (or negatively) affect the risk of developing problems with glucose metabolism. An experiment was designed to study the effects of replacing one third of the dietary lactose by glucose, fructose, or glycerol on glucose homeostasis and insulin sensitivity in veal calves. Forty male Holstein-Friesian (body weight=114 ± 2.4 kg; age=97 ± 1.4 d) calves were fed an MR containing 462 g of lactose/kg (CON), or an MR in which 150 g of lactose/kg of MR was replaced by glucose (GLU), fructose (FRU), or glycerol (GLY). During the first 10d of the trial, all calves received CON. The CON group remained on this diet and the other groups received their experimental diets for a period of 8 wk. Measurements were conducted during the first (baseline) and last week of the trial. A frequently sampled intravenous glucose tolerance test was performed to assess insulin sensitivity and 24 h of urine was collected to measure glucose excretion. During the last week of the trial, a bolus of 1.5 g of [U-(13)C] substrates was added to their respective meals and plasma glucose, insulin, and (13)C-glucose responses were measured. Insulin sensitivity was low at the start of the trial and remained low [1.2 ± 0.1 and 1.0 ± 0.1 (mU/L)(-1) × min(-1)], and no treatment effect was noted. Glucose excretion was low at the start of the trial (3.4 ± 1.0 g/d), but increased in CON and GLU calves (26.9 ± 3.9 and 43.0 ± 10.6g/d) but not in FRU and GLY calves. Postprandial glucose was higher in GLU, lower in FRU, and similar in GLY compared with CON calves. Postprandial insulin was lower in FRU

  17. 49 CFR Appendix B to Part 564 - Information To Be Submitted for Long Life Replaceable Light Sources of Limited Definition

    Science.gov (United States)

    2010-10-01

    ... TRANSPORTATION REPLACEABLE LIGHT SOURCE INFORMATION (Eff. until 12-01-12) Pt. 564, App. B Appendix B to Part 564—Information To Be Submitted for Long Life Replaceable Light Sources of Limited Definition I. Filament or... plane. D. For a light source using excited gas mixtures as a filament, necessary fiducial information...

  18. Use of a trabecular metal implant in ankle arthrodesis after failed total ankle replacement

    Science.gov (United States)

    2010-01-01

    Background and purpose Arthrodesis after failed total ankle replacement is complicated and delayed union, nonunion, and shortening of the leg often occur—especially with large bone defects. We investigated the use of a trabecular metal implant and a retrograde intramedullary nail to obtain fusion. Patients and methods 13 patients with a migrated or loose total ankle implant underwent arthrodesis with the use of a retrograde intramedullary nail through a trabecular metal Tibial Cone. The mean follow-up time was 1.4 (0.6–3.4) years. Results At the last examination, 7 patients were pain-free, while 5 had some residual pain but were satisfied with the procedure. 1 patient was dissatisfied and experienced pain and swelling when walking. The implant-bone interfaces showed no radiographic zones or gaps in any patient, indicating union. Interpretation The method is a new way of simplifying and overcoming some of the problems of performing arthrodesis after failed total ankle replacement. PMID:21067435

  19. Metal ion concentrations in body fluids after implantation of hip replacements with metal-on-metal bearing--systematic review of clinical and epidemiological studies.

    Directory of Open Access Journals (Sweden)

    Albrecht Hartmann

    Full Text Available INTRODUCTION: The use of metal-on-metal (MoM total hip arthroplasty (THA increased in the last decades. A release of metal products (i.e. particles, ions, metallo-organic compounds in these implants may cause local and/or systemic adverse reactions. Metal ion concentrations in body fluids are surrogate measures of metal exposure. OBJECTIVE: To systematically summarize and critically appraise published studies concerning metal ion concentrations after MoM THA. METHODS: Systematic review of clinical trials (RCTs and epidemiological studies with assessment of metal ion levels (cobalt, chromium, titanium, nickel, molybdenum in body fluids after implantation of metalliferous hip replacements. Systematic search in PubMed and Embase in January 2012 supplemented by hand search. Standardized abstraction of pre- and postoperative metal ion concentrations stratified by type of bearing (primary explanatory factor, patient characteristics as well as study quality characteristics (secondary explanatory factors. RESULTS: Overall, 104 studies (11 RCTs, 93 epidemiological studies totaling 9.957 patients with measurement of metal ions in body fluids were identified and analyzed. Consistently, median metal ion concentrations were persistently elevated after implantation of MoM-bearings in all investigated mediums (whole blood, serum, plasma, erythrocytes, urine irrespective of patient characteristics and study characteristics. In several studies very high serum cobalt concentrations above 50 µg/L were measured (detection limit typically 0.3 µg/L. Highest metal ion concentrations were observed after treatment with stemmed large-head MoM-implants and hip resurfacing arthroplasty. DISCUSSION: Due to the risk of local and systemic accumulation of metallic products after treatment with MoM-bearing, risk and benefits should be carefully balanced preoperatively. The authors support a proposed "time out" for stemmed large-head MoM-THA and recommend a restricted

  20. The patient's experience of temporary paralysis from spinal anaesthesia, a part of total knee replacement.

    Science.gov (United States)

    Bager, Louise; Konradsen, Hanne; Dreyer, Pia Sander

    2015-12-01

    The aim of this study was to describe the meaning of being temporary paralysed from spinal anaesthesia when undergoing total knee replacement. Total knee arthroplasty is a common procedure, and regional anaesthesia is used as a method for anaesthetising the patient. The experience is highly individual in substance and duration, and it can extend far beyond care settings as intraoperative care and the postanaesthesia care unit that have been investigated so far. A qualitative phenomenological hermeneutic design was chosen to gain a deeper understanding of the experience of spinal anaesthesia, as a part of having a total knee replacement. Twelve patients were interviewed in March 2014 after undergoing an elective total knee arthroplasty under spinal anaesthesia. The interviews were analysed with a Ricoeur-inspired interpretation method. Three themes were derived from the interviews: 'anaesthesia--an unavoidable necessity', 'an unrecognisable and incomprehensible body' and 'the body returns--joy and agony'. The results reveal that trust in the health care personnel and knowledge of the course of events play a key role in the experience. The trust can be breached by unforeseen events, or if the patient's experiences were not taken into account. The ability of the health care personnel to be in contact, share relevant knowledge with- and compensate for the patient is crucial in the prevention of negative experiences. The results of this study contribute to insights and deeper knowledge that can enhance staff's ability to provide care for patients undergoing total knee arthroplasty in spinal anaesthesia. The results provide perspectives that argue for care in accordance to individual needs. © 2015 John Wiley & Sons Ltd.

  1. Outcome of bonded vs all-ceramic and metal- ceramic fixed prostheses for single tooth replacement.

    Science.gov (United States)

    Karl, Matthias

    2016-01-01

    The conventional treatment of a single missing tooth is most frequently based on the provision of a fixed dental prosthesis (FDPs). A variety of designs and restorative materials are available which have an impact on the treatment outcome. Consequently, it was the aim of this review to compare resin-bonded, all-ceramic and metal-ceramic FDPs based on existing evidence. An electronic literature search using "metal-ceramic" AND "fixed dental prosthesis" AND "clinical, all-ceramic" AND "fixed dental prosthesis" AND "clinical, resin-bonded" AND "fixed dental prosthesis" AND "clinical, fiber reinforced composite" AND "clinical, monolithic" AND "zirconia" AND "clinical" was conducted and supplemented by the manual searching of bibliographies from articles already included. A total of 258 relevant articles were identified. Metal-ceramic FDPs still show the highest survival rates of all tooth-supported restorations. Depending on the ceramic system used, all-ceramic restorations may reach comparable survival rates while the technical complications, i.e. chipping fractures of veneering materials in particular, are more frequent. Resin-bonded FDPs can be seen as long-term provisional restorations with the survival rate being higher in anterior locations and when a cantilever design is applied. Inlay-retained FDPs and the use of fiber-reinforced composites overall results in a compromised long-term prognosis. Recently advocated monolithic zirconia restorations bear the risk of low temperature degradation. Several variables affect treatment planning for a given patient situation, with survival and success rates of different restorative options representing only one factor. The broad variety of designs and materials available for conventional tooth-supported restorations should still be considered as a viable treatment option for single tooth replacement.

  2. Automatic recognition of intersecting features of freeform sheet metal parts

    Institute of Scientific and Technical Information of China (English)

    Chun-jie ZHANG; Xiong-hui ZHOU; Cong-xin LI

    2009-01-01

    This paper presents an approach for recognizing both isolated and intersecting geometric features of freeform surface models of parts, for the purpose of automating the process planning of sheet metal forming. The developed methodology has three major steps: subdivision of B-spline surfaces, detection of protrusions and depressions, and recognition of geometric features for sheet metal forming domain. The input geometry data format of the part is based on an IGES CAD surface model represented in the form of trimmed B-spline surfaces. Each surface is classified or subdivided into different curvature regions with the aid of curvature property surfaces obtained by using symbolic computation of B-spline surfaces. Those regions satisfying a particular geometry and topology relation are recognized as protrusion and depression (DP) shapes. The DP shapes are then classified into different geometric features using a rule-based approach. A verified feasibility study of the developed method is also presented.

  3. Replacing noble metals with alternative materials in plasmonics and metamaterials: how good an idea?

    Science.gov (United States)

    Khurgin, Jacob B

    2017-03-28

    Noble metals that currently dominate the fields of plasmonics and metamaterials suffer from large ohmic losses. Some of the new plasmonic materials, such as doped oxides and nitrides, have smaller material loss, and using them in place of metals carries the promise of reduced-loss plasmonic and metamaterial structures, with sharper resonances and higher field concentrations. This promise is put to a rigorous analytical test in this work, which reveals that having low material loss is not sufficient to have reduced modal loss in plasmonic structures. To reduce the modal loss, it is absolutely necessary for the plasma frequency to be significantly higher than the operational frequency. Using examples of nanoparticle plasmons and gap plasmons one comes to the conclusion that, even in the mid-infrared spectrum, metals continue to hold an advantage over alternative media when it comes to propagation distances and field enhancements. Of course, the new materials still have an application niche where high absorption loss is beneficial, e.g. in medicine and thermal photovoltaics.This article is part of the themed issue 'New horizons for nanophotonics'. © 2017 The Author(s).

  4. Replacing noble metals with alternative materials in plasmonics and metamaterials: how good an idea?

    Science.gov (United States)

    Khurgin, Jacob B.

    2017-03-01

    Noble metals that currently dominate the fields of plasmonics and metamaterials suffer from large ohmic losses. Some of the new plasmonic materials, such as doped oxides and nitrides, have smaller material loss, and using them in place of metals carries the promise of reduced-loss plasmonic and metamaterial structures, with sharper resonances and higher field concentrations. This promise is put to a rigorous analytical test in this work, which reveals that having low material loss is not sufficient to have reduced modal loss in plasmonic structures. To reduce the modal loss, it is absolutely necessary for the plasma frequency to be significantly higher than the operational frequency. Using examples of nanoparticle plasmons and gap plasmons one comes to the conclusion that, even in the mid-infrared spectrum, metals continue to hold an advantage over alternative media when it comes to propagation distances and field enhancements. Of course, the new materials still have an application niche where high absorption loss is beneficial, e.g. in medicine and thermal photovoltaics. This article is part of the themed issue 'New horizons for nanophotonics'.

  5. Why large-head metal-on-metal hip replacements are painful: the anatomical basis of psoas impingement on the femoral head-neck junction.

    Science.gov (United States)

    Cobb, J P; Davda, K; Ahmad, A; Harris, S J; Masjedi, M; Hart, A J

    2011-07-01

    Large-head metal-on-metal total hip replacement has a failure rate of almost 8% at five years, three times the revision rate of conventional hip replacement. Unexplained pain remains a feature of this type of arthroplasty. All designs of the femoral component of large-head metal-on-metal total hip replacements share a unique characteristic: a subtended angle of 120° defining the proportion of a sphere that the head represents. Using MRI, we measured the contact area of the iliopsoas tendon on the femoral head in sagittal reconstruction of 20 hips of patients with symptomatic femoroacetabular impingement. We also measured the articular extent of the femoral head on 40 normal hips and ten with cam-type deformities. Finally, we performed virtual hip resurfacing on normal and cam-type hips, avoiding overhang of the metal rim inferomedially. The articular surface of the femoral head has a subtended angle of 120° anteriorly and posteriorly, but only 100° medially. Virtual surgery in a normally shaped femoral head showed a 20° skirt of metal protruding medially where iliopsoas articulates. The excessive extent of the large-diameter femoral components may cause iliopsoas impingement independently of the acetabular component. This may be the cause of postoperative pain with these implants.

  6. Global Earthing Systems: Characterization of Buried Metallic Parts

    OpenAIRE

    Tommasini, Riccardo; Colella, Pietro; Pons, Enrico

    2016-01-01

    International Standards IEC 61936-1 and EN 50522 define a Global Earthing System (GES) as the earthing network, created by the interconnection of local earthing systems, that should guarantee the absence of dangerous touch voltages. This is achieved through two effects: the division of the earth fault current between many earthing systems and the creation of a quasi equipotential surface. The second effect can be enhanced by the presence of buried metallic parts, such as light poles and water...

  7. PRODUCTION OF PROTOTYPE PARTS USING DIRECT METAL LASER SINTERING TECHNOLOGY

    Directory of Open Access Journals (Sweden)

    Josef Sedlak

    2015-08-01

    Full Text Available Unconventional methods of modern materials preparation include additive technologies which involve the sintering of powders of different chemical composition, granularity, physical, chemical and other utility properties. The technology called Rapid Prototyping, which uses different technological principles of producing components, belongs to this type of material preparation. The Rapid Prototyping technology facilities use photopolymers, thermoplastics, specially treated paper or metal powders. The advantage is the direct production of metal parts from input data and the fact that there is no need for the production of special tools (moulds, press tools, etc.. Unused powder from sintering technologies is re-used for production 98% of the time, which means that the process is economical, as well as ecological.The present paper discusses the technology of Direct Metal Laser Sintering (DMLS, which falls into the group of additive technologies of Rapid Prototyping (RP. The major objective is a detailed description of DMLS, pointing out the benefits it offers and its application in practice. The practical part describes the production and provides an economic comparison of several prototype parts that were designed for testing in the automotive industry.

  8. Metallization on FDM Parts Using the Chemical Deposition Technique

    Directory of Open Access Journals (Sweden)

    Azhar Equbal

    2014-08-01

    Full Text Available Metallization of ABS (acrylonitrile-butadiene-styrene parts has been studied on flat part surfaces. These parts are fabricated on an FDM (fused deposition modeling machine using the layer-wise deposition principle using ABS as a part material. Electroless copper deposition on ABS parts was performed using two different surface preparation processes, namely ABS parts prepared using chromic acid for etching and ABS parts prepared using a solution mixture of sulphuric acid and hydrogen peroxide (H2SO4/H2O2 for etching. After surface preparations using these routes, copper (Cu is deposited electrolessly using four different acidic baths. The acidic baths used are 5 wt% CuSO4 (copper sulfate with 15 wt% of individual acids, namely HF (hydrofluoric acid, H2SO4 (sulphuric acid, H3PO4 (phosphoric acid and CH3COOH (acetic acid. Cu deposition under different acidic baths used for both the routes is presented and compared based on their electrical performance, scanning electron microscopy (SEM and energy dispersive X-ray spectrometry (EDS. The result shows that chromic acid etched samples show better electrical performance and Cu deposition in comparison to samples etched via H2SO4/H2O2.

  9. Microstructure-Based Counterfeit Detection in Metal Part Manufacturing

    Science.gov (United States)

    Dachowicz, Adam; Chaduvula, Siva Chaitanya; Atallah, Mikhail; Panchal, Jitesh H.

    2017-08-01

    Counterfeiting in metal part manufacturing has become a major global concern. Although significant effort has been made in detecting the implementation of such counterfeits, modern approaches suffer from high expense during production, invasiveness during manufacture, and unreliability in practice if parts are damaged during use. In this paper, a practical microstructure-based counterfeit detection methodology is proposed, which draws on inherent randomness present in the microstructure as a result of the manufacturing process. An optical Physically Unclonable Function (PUF) protocol is developed which takes a micrograph as input and outputs a compact, unique string representation of the micrograph. The uniqueness of the outputs and their robustness to moderate wear and tear is demonstrated by application of the methodology to brass samples. The protocol is shown to have good discriminatory power even between samples manufactured in the same batch, and runs on the order of several seconds per part on inexpensive machines.

  10. Effects of partly replacing dietary starch with fiber and fat on milk production and energy partitioning.

    Science.gov (United States)

    Boerman, J P; Potts, S B; VandeHaar, M J; Lock, A L

    2015-10-01

    The effects of partly replacing dietary starch with fiber and fat to provide a diet with similar net energy for lactation (NEL) density on yields of milk and milk components and on energy partitioning were evaluated in a crossover design experiment. Holstein cows (n = 32; 109 ± 22 d in milk, mean ± standard deviation) were randomly assigned to treatment sequence. Treatments were a high-starch diet containing 33% corn grain (mixture of dry ground and high-moisture corn; HS) or a high-fiber, high-fat diet containing 2.5% palmitic acid-enriched fatty acid (FA) supplement (HFF). Diets contained corn silage, alfalfa silage, and wheat straw as forage sources; HS contained 32% starch, 3.2% FA, and 25% neutral detergent fiber, whereas HFF contained 16% starch, 5.4% FA, and 33% neutral detergent fiber. Compared with HS, the HFF treatment reduced milk yield, milk protein concentration, and milk protein yield, but increased milk fat concentration, milk fat yield, milk energy output, and milk to feed ratio (energy-corrected milk/dry matter intake). The HFF treatment reduced the yield of de novo synthesized ( 16-carbon) milk FA was not different. The HFF treatment increased plasma concentrations of triglycerides and nonesterified fatty acids, but decreased plasma concentration of insulin. Compared with HS, the HFF treatment reduced body weight gain, change in body condition score, and fat thickness over the rump and rib. Calculated body energy gain, as a fraction of NEL use, was less for HFF than HS, whereas milk energy as a fraction of NEL use was increased for HFF. We concluded that the 2 treatments resulted in similar apparent NEL densities and intakes, but the HS treatment partitioned more energy toward body gain whereas the HFF treatment partitioned more energy toward milk. A high-fiber, high-fat diet might diminish the incidence of over conditioning in mid-lactation cows while maintaining high milk production. Copyright © 2015 American Dairy Science Association

  11. Review on progressive microforming of bulk metal parts directly using sheet metals (Keynote Paper

    Directory of Open Access Journals (Sweden)

    Fu M.W.

    2015-01-01

    Full Text Available Due to the ubiquitous trend of product miniaturization, energy saving and weight reduction, micro/meso-scale parts have been widely used in many industrial clusters. Micromanufacturing processes for production of such micro/meso-scale parts are thus critically needed. Microforming, as one of these micro manufacturing processes, is a promising process and thus got many explorations and researches. Compared with the research on size effect affected deformation behaviours, less attention has been paid to the process development for mass production of micro-parts. The product quality and fabrication productivity of micro-parts depend on the involved process chain. To address the difficulty in handling and transporting of the micro-sized workpiece, development of a progressive microforming process for directly fabricating bulk micro-parts using sheet metals seems quite promising as it avoids or facilitates billet handling, transportation, positioning, and ejection in the process chain. In this paper, an intensive review on the latest development of progressive microforming technologies is presented. First of all, the paper summarizes the characteristic of progressive microforming directly using sheet metal. The size effect-affected deformation behaviour and the dimensional accuracy, deformation load, ductile fracture, and the surface finish of the microformed parts by progressive microforming using sheet metals are then presented. Finally, some research issues from the implementation of mass production perspective are also discussed.

  12. A comparison of leg length and femoral offset discrepancies in hip resurfacing, large head metal-on- metal and conventional total hip replacement: a case series

    Directory of Open Access Journals (Sweden)

    Herman Katie A

    2011-12-01

    Full Text Available Abstract Background A discrepancy in leg length and femoral offset restoration is the leading cause of patient dissatisfaction in hip replacement surgery and has profound implications on patient quality of life. The aim of this study is to compare biomechanical hip reconstruction in hip resurfacing, large-diameter femoral head hip arthroplasty and conventional total hip replacement. Method Sixty patient's post-operative radiographs were reviewed; 20 patients had a hip resurfacing (HR, 20 patients had a Large Head Metal-on-metal (LHM hip replacement and 20 patients had a conventional small head Total Hip Replacement (THR. The leg length and femoral offset of the operated and unoperated hips were measured and compared. Results Hip resurfacing accurately restored hip biomechanics with no statistical difference in leg length (P = 0.07 or femoral offset (P = 0.95 between the operated and non-operative hips. Overall HR was superior for reducing femoral offset discrepancies where it had the smallest bilateral difference (-0.2%, P = 0.9. The traditional total hip replacement was least effective at restoring the hip anatomy. Conclusion The use of a larger-diameter femoral head in hip resurfacing does not fully account for the superior biomechanical restoration, as LHM did not restore femoral offset as accurately. We conclude that restoration of normal hip biomechanics is best achieved with hip resurfacing.

  13. The patient's experience of temporary paralysis from spinal anaesthesia, a part of total knee replacement

    DEFF Research Database (Denmark)

    Bager, Louise; Konradsen, Hanne; Dreyer, Pia Sander

    2015-01-01

    AIMS AND OBJECTIVES: The aim of this study was to describe the meaning of being temporary paralysed from spinal anaesthesia when undergoing total knee replacement. BACKGROUND: Total knee arthroplasty is a common procedure, and regional anaesthesia is used as a method for anaesthetising the patien...

  14. INVESTIGATION OF METAL CHIP HEATING PROCESS (Part 2

    Directory of Open Access Journals (Sweden)

    O. M. Dyakonov

    2008-01-01

    Full Text Available A physical and mathematical model of metal chip heating process in a continuous muffle furnace has been worked out. The model describes a conjugated heat- and mass transfer in the given  furnace (conductive, convective, radiant, heating of chips and furnace parts, lubricant-coolant evaporation, oil vapour combustion, flue gas movement. The received set of equations is a completed one that allows to solve a specified problem that is to find an optimum height for a furnace with the given productivity  and minimum natural gas consumption. 

  15. Part height control of laser metal additive manufacturing process

    Science.gov (United States)

    Pan, Yu-Herng

    Laser Metal Deposition (LMD) has been used to not only make but also repair damaged parts in a layer-by-layer fashion. Parts made in this manner may produce less waste than those made through conventional machining processes. However, a common issue of LMD involves controlling the deposition's layer thickness. Accuracy is important, and as it increases, both the time required to produce the part and the material wasted during the material removal process (e.g., milling, lathe) decrease. The deposition rate is affected by multiple parameters, such as the powder feed rate, laser input power, axis feed rate, material type, and part design, the values of each of which may change during the LMD process. Using a mathematical model to build a generic equation that predicts the deposition's layer thickness is difficult due to these complex parameters. In this thesis, we propose a simple method that utilizes a single device. This device uses a pyrometer to monitor the current build height, thereby allowing the layer thickness to be controlled during the LMD process. This method also helps the LMD system to build parts even with complex parameters and to increase material efficiency.

  16. Joining technology for parts for plastic and thin sheet metal parts; Fuegetechniken fuer Bauteile aus Kunststoff und duennwandigem Metall

    Energy Technology Data Exchange (ETDEWEB)

    Ahlers-Hestermann, G. [BOELLHOFF, Bielefeld (Germany)

    2001-07-01

    With the ongoing application of new materials (Al, Mg, Plastic) as an alternative to steel in light-weight body in white construction it is necessary to develop and use other joining and fixing technologies than spot welding, bolt-and nut-welding. These new technologies for example are mechanical joining technology as clinching and self-pierce-riveting, blind-riveting and special elements to fix other parts as blind-rivets and self-piercing nuts and bolts. These products are mainly used for metal materials and mixed structures. To fix other parts to plastic-parts direct-screwing or the after-moulding-technology with metal or plastic inserts is used. (orig.) [German] Mit der verstaerkten Anwendung von weiteren Werkstoffen (Al, Mg, Kunststoffe) als Stahl im Automobilbau ist die Notwendigkeit erwachsen, alternative Fuege- und Befestigungstechniken zum Punktschweissen, Bolzen- und Mutternschweissen zu entwickeln. Hierzu gehoeren die mechanischen Fuegetechniken wie Stanznieten, Clinchen, Blindnieten sowie die sogenannten Funktionselemente zum Befestigen von Anbauteilen, wie Blind- und Stanznietmuttern und -bolzen. Diese Verfahren werden ueberwiegend fuer metallische Werkstoffe oder bei Mischbauweise angewandt. Fuer die Befestigung an Kunststoffbauteilen wird die Direktverschraubung oder die after-moulding-technik (AMTEC {sup registered}) verwendet. (orig.)

  17. Understanding Active Metal Reaction Kinetis with Cu-Mg Replacement Reaction

    Indian Academy of Sciences (India)

    Ilhami Ceyhun; Zafer Karagolge

    2017-02-01

    Metal substitution reactions are simple redox reactions. Thesereactions demonstrate the relative activity and the electrochemicalseries of metals. In particular, the purpose of thisstudy is to help students comprehend the displacement reactionamong, Mg metal and solutions containing Cu$^{+2}$, Ni$^{+2}$,Pb$^{+2}$, Cd$^{+2}$, Co$^{+2}$. This study is an important experiment towardsunderstanding reaction kinetics.

  18. Effect of metal cation replacement on the electronic structure of metalorganic halide perovskites: Replacement of lead with alkaline-earth metals

    Science.gov (United States)

    Pazoki, Meysam; Jacobsson, T. Jesper; Hagfeldt, Anders; Boschloo, Gerrit; Edvinsson, Tomas

    2016-04-01

    Organic and inorganic lead halogen perovskites, and in particular, C H3N H3Pb I3 , have during the last years emerged as a class of highly efficient solar cell materials. Herein we introduce metalorganic halogen perovskite materials for energy-relevant applications based on alkaline-earth metals. Based on the classical notion of Goldschmidt's rules and quantum mechanical considerations, the three alkaline-earth metals, Ca, Sr, and Ba, are shown to be able to exchange lead in the perovskite structure. The three alkaline-earth perovskites, C H3N H3Ca I3,C H3N H3Sr I3 , and C H3N H3Ba I3 , as well as the reference compound, C H3N H3Pb I3 , are in this paper investigated with density functional theory (DFT) calculations, which predict these compounds to exist as stable perovskite materials, and their electronic properties are explored. A detailed analysis of the projected molecular orbital density of states and electronic band structure from DFT calculations were used for interpretation of the band-gap variations in these materials and for estimation of the effective masses of the electrons and holes. Neglecting spin-orbit effects, the band gap of MACa I3,MASr I3 , and MABa I3 were estimated to be 2.95, 3.6, and 3.3 eV, respectively, showing the relative change expected for metal cation exchange. The shifts in the conduction band (CB) edges for the alkaline-earth perovskites were quantified using scalar relativistic DFT calculations and tight-binding analysis, and were compared to the situation in the more extensively studied lead halide perovskite, C H3N H3Pb I3 , where the change in the work function of the metal is the single most important factor in tuning the CB edge and band gap. The results show that alkaline-earth-based organometallic perovskites will not work as an efficient light absorber in photovoltaic applications but instead could be applicable as charge-selective contact materials. The rather high CB edge and the wide band gap together with the large

  19. replacement of the heart of the CMS experiment - the pixel #detector. Part2

    CERN Multimedia

    Brice, Maximilien

    2017-01-01

    This week, one of the Large Hadron Collider’s experiments gets a “heart transplant”. --- Physicists and engineers are replacing the heart of the CMS experiment - the pixel #detector. This will improve CMS’s ability to make precise measurements on aspects of the Standard Model, including the properties of the #HiggsBoson. The #LHC and its experiments are currently preparing to wake up this spring, when the accelerator will begin to collide particles once more at close to the speed of light. --- Today at 12:15 CET, join us live on #Facebook and ask us anything: https://www.facebook.com/cern/

  20. AANA Journal Course: Update for nurse anesthetists--part-4--transcatheter aortic valve replacement.

    Science.gov (United States)

    Contrera, Peggy; Cushing, Mary

    2013-10-01

    Aortic stenosis is the most frequently acquired heart disease, and the prevalence is rising because of the aging population. If the disease is left untreated, survival in symptomatic patients averages only 2 to 3 years. Surgical aortic valve replacement is the only definitive treatment, yet 30% of elderly patients are not considered candidates because the presence of comorbidities makes the risk of sternotomy and cardiopulmonary bypass prohibitively high. Transcatheter aortic valve replacement (TAVR) is an innovative, high-tech, less invasive alternative. The procedure is usually performed using general anesthesia and a multidisciplinary team from interventional cardiology and cardiothoracic surgery in a "hybrid" operating environment with advanced imaging capabilities. There are 2 major catheter-based approaches to the aortic valve: retrograde percutaneous through the femoral artery and aorta or direct antegrade through a thoracotomy and the left ventricular apex. Apnea and rapid ventricular pacing are used to interrupt cardiac ejection during balloon valvuloplasty and prosthesis implantation. The most significant complications include vascular damage, stroke, paravalvular aortic insufficiency, and heart block. Outcomes studies comparing TAVR with medical management demonstrate improved patient survival, functional status, and quality of life. Currently TAVR is considered the treatment of choice for patients who are not surgical candidates and is a proven alternative for high-risk surgical candidates.

  1. The modular endoprosthesis for mandibular body replacement. Part 1: Mechanical testing of the reconstruction

    NARCIS (Netherlands)

    Wong, R.C.; Tideman, H.; Merkx, M.A.W.; Jansen, J.A.; Goh, S.M.

    2012-01-01

    INTRODUCTION: In this paper we present the results of the mechanical testing of a new generation modular endoprosthesis, which has been designed to improve the results of mandibular reconstruction. MATERIALS AND METHODS: The new cementless endoprosthesis consists of a male part, a female part (both

  2. Development and characterization of polymers-metallic hot embossing process for manufacturing metallic micro-parts

    Science.gov (United States)

    Sahli, M.; Millot, C.; Gelin, J.-C.; Barrière, T.

    2011-01-01

    In the recent years, hot embossing process becomes a promising process for the replication of polymer micro-structures associated to its manufacturing capability related to a relatively low component cost. This rising demand has prompted the development of various micro-manufacturing techniques in an attempt to get micro-parts in large batch. The paper investigates the way to get metallic micro-parts through the hot embossing process. The micro-manufacturing process consists in three stages. In the first one, the different metallic feedstocks with 50 to 60% powder loading in volume have been prepared with adapted polymers/powders formulations. In a second stage, an elastomeric master has been used to obtain micro-parts on a plastic loaded substrate with developed mixture based on polypropylene, paraffin wax and stearic acid. Finally, a thermal debinding stage in nitrogen atmosphere followed by a solid state pre-sintering stage has been applied, in order to eliminate the pores between powder particles in the debinded components. Then the porous components are agglomerated by solid state diffusion after heating to a temperature slightly lower than the melting temperature related to the material used in the process, to form an homogenous structure when full densification is achieved. The advantages of this approach include: rapid manufacturing of injection tools with high-quality, easy demoulding of metallic parts from the elastomeric moulds and great flexibility related to the choices of material. The paper describes all the processing stages and the way to characterize the geometrical, physical and mechanical properties of the resulting micro-parts.

  3. Wood ash used as partly sand and/or cement replacement in mortar

    DEFF Research Database (Denmark)

    Ottosen, Lisbeth M.; Hansen, Esben Østergaard; Jensen, Pernille Erland;

    2016-01-01

    Wood ash (WA) is the residue generated during incineration of wood and wood products. The WAs in focus of this work are from incineration of virgin wood. Physical and chemical properties of WA vary significantly depending on many factors related to the wood species and the incineration process...... from the differences in ash characteristics to the properties of the mortar samples. The characteristics of the ashes did vary considerably. For example, one ash had very high loss on ignition (LoI) of 14% compared to 3% for the other ashes. Ash solubility in water ranged from 18% to 28%. Two...... of the ashes were dry and sampled just after the incineration, whereas one ash had a water content of 15%, because the ash was sprayed with water to avoid dust during ash handling at the incineration plant. Regardless of replacing cement or sand with WAs, the compressive strength decreased compared...

  4. Automated electrodeposition of bimetallic noble-metal nanoclusters via redox-replacement reactions for electrocatalysis

    CSIR Research Space (South Africa)

    Mkwizu, TS

    2009-01-01

    Full Text Available Nanoclusters of bimetallic composition involving platinum with gold or ruthenium were sequentially deposited via redoxreplacement of electrodeposited sacrificial Cu adlayers for controlling the deposition of the noble metals. These steps were...

  5. A new strategy for stiffness evaluation of sheet metal parts

    Science.gov (United States)

    Cai, Q.; Volk, W.; Düster, A.; Rank, E.

    2011-08-01

    In the automotive industry, surfaces of styling models are shaped very often in physical models. For example, in the styling process of a car body important design work is realized by clay models and the resulting geometry information typically comes from optical scans. The scanned data is given in the form of point clouds which is then utilized in the virtual planning process for engineering work, e.g. to evaluate the load-carrying capacity. This is an important measure for the stiffness of the car body panels. In this contribution, the following two issues are discussed: what is the suitable geometric representation of the stiffness of the car body and how it is computed if only discrete point clouds exist. In the first part, the suitable geometric representation is identified by constructing continuous CAD models with different geometric parameters, e.g. Gaussian curvature and mean curvature. The stiffness of models is then computed in LS-DYNA and the influence of different geometric parameters is presented based on the simulation result. In the second part, the point clouds from scanned data, rather than continuous CAD models, are directly utilized to estimate the Gaussian curvature, which is normally derived from continuous surfaces. The discrete Gauss-Bonnet algorithm is applied to estimate the Gaussian curvature of the point clouds and the sensitivity of the algorithm with respect to the mesh quality is analyzed. In this way, the stiffness evaluation process in an early stage can be accelerated since the transformation from discrete data to continuous CAD data is labor-intensive. The discrete Gauss-Bonnet algorithm is finally applied to a sheet metal model of the BMW 3 series.

  6. Topological Superconductivity in Ferromagnetic Metal Chains: Part I

    Science.gov (United States)

    Li, Jian; Chen, Hua; Drozdov, Ilya; Yazdani, Ali; Bernevig, Bogdan; MacDonald, Allan

    2015-03-01

    Recent experiments have demonstrated superconductivity induced in ferromagnetic atomic chains as a new route to the research of Majorana physics. In this talk we discuss the theory behind these experiments. We will first present a generic picture for how superconductivity is induced in ferromagnetic metal chains through coupling to a superconductor with strong spin-orbit coupling, and explain why this hybrid system is a plausible new platform in searching for topological superconductivity. We will then present a tight-binding model associated with the existing experiments. We reveal a new chain magnetic symmetry that is able to stabilize multiple Majorana end modes in the absence of disorder, resulting in a one-dimensional crystalline topological superconductor. We show phase diagrams in terms of such topological phases and point out their relevance to the existing experiments. In the last part of this talk we will briefly discuss some other directions of research based on the new platform, including braiding Majorana quasi-particles in ferromagnetic chains, as well as realizing topological superconductivity in two-dimensional ferromagnetic thin films.

  7. Can rapeseed oil replace olive oil as part of a Mediterranean-style diet?

    Science.gov (United States)

    Hoffman, Richard; Gerber, Mariette

    2014-12-14

    The present narrative review compares evidence from experimental, epidemiological and clinical studies of the health benefits of rapeseed oil (RO) (known as canola oil) and olive oil (OO) in order to assess whether rapeseed oil is suitable as a sustainable alternative to OO as part of a Mediterranean-style diet in countries where olive trees do not grow. From epidemiological studies, the evidence for cardiovascular protection afforded by extra-virgin OO is 'convincing', and for cancers 'limited-suggestive', especially oestrogen receptor-negative breast cancer, but more studies are required in relation to cognitive impairment. Evidence for RO is limited to short-term studies on the biomarkers of risk factors for CVD. Any benefits of RO are likely to be due to α-linolenic acid; however, it is prone to oxidation during frying. We conclude that due to a lack of evidence from observational or intervention studies indicating that RO has comparable health benefits to extra-virgin OO, RO cannot currently be recommended as a suitable substitute for extra-virgin OO as part of a Mediterranean-style diet.

  8. Replacing Noble Metals with Alternative Materials in Plasmonics and Metamaterials: how good an idea?

    CERN Document Server

    Khurgin, Jacob B

    2016-01-01

    Noble metals that currently dominate the fields of plasmonics and metamaterials suffer from large ohmic losses. New plasmonic materials, such as doped oxides and nitrides, have smaller material loss, and, using them in place of metals carries promise of reduced-loss plasmonic and metamaterial structures, with sharper resonances and higher field concentration. This promise is put to a rigorous analytical test in this work which reveals that having low material loss is not sufficient to have a reduced modal loss in plasmonic structures. To reduce the modal loss it is absolutely necessary for the plasma frequency to be significantly higher than the operational frequency. Using examples of nanoparticle plasmons and gap plasmons one comes to the conclusion that even in the mid-infrared spectrum metals continue to hold advantage over the alternative media. The new materials may still find application niche where the high absorption loss is beneficial, e.g. in medicine and thermal photovoltaics.

  9. Continuous renal replacement therapy amino acid, trace metal and folate clearance in critically ill children

    Science.gov (United States)

    We hypothesized that continuous veno-venous hemodialysis (CVVHD) results in amino acid, trace metals, and folate losses, thereby adversely impacting nutrient balance. Critically ill children receiving CVVHD were studied prospectively for 5 days. Blood concentrations, amino acids, copper, zinc, man...

  10. The immunobiology of cobalt: demonstration of a potential aetiology for inflammatory pseudotumours after metal-on-metal replacement of the hip.

    Science.gov (United States)

    Lawrence, H; Deehan, D; Holland, J; Kirby, J; Tyson-Capper, A

    2014-09-01

    Abnormal wear of cobalt-containing metal-on-metal joints is associated with inflammatory pseudotumours. Cobalt ions activate human toll-like receptor 4 (TLR4), which normally responds to bacterial lipopolysaccharide (LPS) in sepsis. Activation of TLR4 by LPS increases the expression of chemokines IL-8 and CXCL10, which recruit leukocytes and activated T-cells, respectively. This study was designed to determine whether cobalt induces a similar inflammatory response to LPS by promoting the expression of IL-8 and CXCL10. A human monocytic cell line, derived from acute monocytic leukaemia, was treated with cobalt ions and expression of IL-8 and CXCL10 measured at mRNA and protein levels. Cobalt-treated macrophages showed a 60-fold increase in IL-8 mRNA, and an eightfold increase in production of the mature chemokine (both p cobalt (both p cobalt-mediated increase in IL-8 and CXCL10 expression. These findings suggest that cobalt ions induce inflammation similar to that observed during sepsis by the simultaneous activation of two TLR4-mediated signalling pathways. These pathways result in increased production of IL-8 and CXCL10, and may be implicated in pseudotumour formation following metal-on-metal replacement. ©2014 The British Editorial Society of Bone & Joint Surgery.

  11. Prospective comparison study of one-year outcomes for all titanium total temporomandibular joint replacements in patients allergic to metal and cobalt-chromium replacement joints in patients not allergic to metal.

    Science.gov (United States)

    Hussain, O T; Sah, S; Sidebottom, A J

    2014-01-01

    We aimed to ascertain whether there are any early differences in outcome between all titanium temporomandibular joint (TMJ) prostheses in patients allergic to metal and standard cobalt-chromium prostheses in patients not allergic to metal. All patients who had primary TMJ prostheses placed with one-year follow-up between March 2003 and February 2011 were included. We reviewed the basic characteristics of patients. The outcome variables measured included disease, pain, mouth opening, and diet. A total of 55 patients with 77 joint replacements fulfilled the inclusion criteria. Forty patients had standard cobalt-chromium alloy (Co-Cr-Mo) prostheses (20 unilateral and 20 bilateral), and 15 had all titanium prostheses (13 unilateral and 2 bilateral). Osteoarthritis was the most common disease in both groups. There was significant improvement in pain score at reviews at 6 weeks (p=0.001) and 12 months (p=0.03). Values between groups were not significant (p=0.48 at 6 weeks, and p=0.10 at 1 year). Mouth opening in each group improved significantly with continued gains between assessments at 6 weeks and 12 months (p=0.001) but there were no significant differences between groups. Diet scores were significantly improved one year postoperatively in both groups (p=0.001), but differences between groups were not significant (p=0.90). At one year, outcomes for all titanium prostheses in patients allergic to metal were similarly favourable to those in patients who had no hypersensitivity to metal and had standard prostheses. No patient developed a hypersensitivity reaction, and no all titanium prosthesis failed during the one-year follow-up period. Copyright © 2013 The British Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

  12. Comparison of gait parameters in distal femoral replacement using a metallic endoprosthesis versus allograft reconstruction.

    Science.gov (United States)

    AlGheshyan, Fahad; Eltoukhy, Moataz; Zakaria, Khaled; Temple, Harry Thomas; Asfour, Shihab

    2015-10-01

    Restoration of gait mechanics after reconstruction have been associated with improved functional outcomes and increased longevity of the reconstruction. The goal of this study is to compare the gait mechanics of an allograft reconstruction of the distal femur to both metallic endoprosthetic reconstruction relative to normal control subjects. Gait parameters were captured using motion capture system, and then analyzed and compared for patients with metallic endoprosthetic reconstructions, and patients with allograft reconstructions of the distal femur following resection of malignant bone tumor, with subjects having no history of musculoskeletal disorders serving as a control group. All reconstructed distal femurs following tumor resection resulted in decreased range of motion reflected in observed flexion/extension angles compared to the normal limbs. The allograft reconstructed knees demonstrated normal patterns of rotation whereas the metal subjects had abnormal patterns of rotation and statistically significant differences in rotational moments. Allograft distal femoral reconstruction after malignant excision remains a viable option for surgeons faced with problems associated with iatrogenic muscle, bone and soft tissue defects.

  13. A Retrieval Algorithm of Sheet Metal Parts Based on Relationships of Features

    Institute of Scientific and Technical Information of China (English)

    WANG Dawei; YAN Guangrong; LEI Yi; ZHANG Jiaying

    2012-01-01

    With the rapid increase in the number of three-dimensional (3D) models each year,to quickly and easily find the part desired has become a big challenge of enterprises.Meanwhile,many methods and algorithms have been proposed for part retrieval.However,most of the existing methods are designed for mechanical parts,and can not be well worked for sheet metal part retrieval.An approach to feature-based retrieval of sheet metal parts is presented.Firstly,the features frequently used in sheet metal part design are chosen as the "key words" in retrieval.Based on those features,a relative position model is built to express the different relationships of the features in 3D space.Secondly,a description method of the model is studied.With the description method the relative position of features in sheet metal parts can be expressed by four location description matrices.Thirdly,based on the relative position model and location description matrices,the equivalent definition of relationships of two feature groups is given which is the basis to calculate the similarity of two sheet metal parts.Next,the formula of retrieval algorithm for sheet metal parts is given.Finally,a prototype system is developed to test and verify the effectiveness of the retrieval method suggested.Experiments verify that the new method is able to meet the requirements of searching sheet metal parts and possesses potentials in practical application.

  14. Directed Replacement

    CERN Document Server

    Karttunen, L

    1996-01-01

    This paper introduces to the finite-state calculus a family of directed replace operators. In contrast to the simple replace expression, UPPER -> LOWER, defined in Karttunen (ACL-95), the new directed version, UPPER @-> LOWER, yields an unambiguous transducer if the lower language consists of a single string. It transduces the input string from left to right, making only the longest possible replacement at each point. A new type of replacement expression, UPPER @-> PREFIX ... SUFFIX, yields a transducer that inserts text around strings that are instances of UPPER. The symbol ... denotes the matching part of the input which itself remains unchanged. PREFIX and SUFFIX are regular expressions describing the insertions. Expressions of the type UPPER @-> PREFIX ... SUFFIX may be used to compose a deterministic parser for a ``local grammar'' in the sense of Gross (1989). Other useful applications of directed replacement include tokenization and filtering of text streams.

  15. Effects of holding pressure and process temperatures on the mechanical properties of moulded metallic parts

    DEFF Research Database (Denmark)

    Islam, Aminul; Hansen, Hans Nørgaard; Esteves, N.M.;

    2013-01-01

    on the moulded metallic parts. Stainless steel 316L is used in the investigation to produce the specimen by metal injection moulding (MIM) and multiple analyses were carried out on samples produced with different combinations of holding pressure, mould temperature and melt temperature. Finally, the parts were...

  16. Automobile sheet metal part production with incremental sheet forming

    Directory of Open Access Journals (Sweden)

    İsmail DURGUN

    2016-02-01

    Full Text Available Nowadays, effect of global warming is increasing drastically so it leads to increased interest on energy efficiency and sustainable production methods. As a result of adverse conditions, national and international project platforms, OEMs (Original Equipment Manufacturers, SMEs (Small and Mid-size Manufacturers perform many studies or improve existing methodologies in scope of advanced manufacturing techniques. In this study, advanced manufacturing and sustainable production method "Incremental Sheet Metal Forming (ISF" was used for sheet metal forming process. A vehicle fender was manufactured with or without die by using different toolpath strategies and die sets. At the end of the study, Results have been investigated under the influence of method and parameters used.Keywords: Template incremental sheet metal, Metal forming

  17. The contact mechanics and occurrence of edge loading in modular metal-on-polyethylene total hip replacement during daily activities.

    Science.gov (United States)

    Hua, Xijin; Li, Junyan; Jin, Zhongmin; Fisher, John

    2016-06-01

    The occurrence of edge loading in hip joint replacement has been associated with many factors such as prosthetic design, component malposition and activities of daily living. The present study aimed to quantify the occurrence of edge loading/contact at the articulating surface and to evaluate the effect of cup angles and edge loading on the contact mechanics of a modular metal-on-polyethylene (MoP) total hip replacement (THR) during different daily activities. A three-dimensional finite element model was developed based on a modular MoP bearing system. Different cup inclination and anteversion angles were modelled and six daily activities were considered. The results showed that edge loading was predicted during normal walking, ascending and descending stairs activities under steep cup inclination conditions (≥55°) while no edge loading was observed during standing up, sitting down and knee bending activities. The duration of edge loading increased with increased cup inclination angles and was affected by the cup anteversion angles. Edge loading caused elevated contact pressure at the articulating surface and substantially increased equivalent plastic strain of the polyethylene liner. The present study suggested that correct positioning the component to avoid edge loading that may occur during daily activities is important for MoP THR in clinical practice.

  18. Effect of 3D physiological loading and motion on elastohydrodynamic lubrication of metal-on-metal total hip replacements.

    Science.gov (United States)

    Gao, Leiming; Wang, Fengcai; Yang, Peiran; Jin, Zhongmin

    2009-07-01

    An elastohydrodynamic lubrication (EHL) simulation of a metal-on-metal (MOM) total hip implant was presented, considering both steady state and transient physiological loading and motion gait cycle in all three directions. The governing equations were solved numerically by the multi-grid method and fast Fourier transform in spherical coordinates, and full numerical solutions were presented included the pressure and film thickness distribution. Despite small variations in the magnitude of 3D resultant load, the horizontal anterior-posterior (AP) and medial-lateral (ML) load components were found to translate the contact area substantially in the corresponding direction and consequently to result in significant squeeze-film actions. For a cup positioned anatomically at 45 degrees , the variation of the resultant load was shown unlikely to cause the edge contact. The contact area was found within the cup dimensions of 70-130 degrees and 90-150 degrees in the AP and ML direction respectively even under the largest translations. Under walking conditions, the horizontal load components had a significant impact on the lubrication film due to the squeeze-film effect. The time-dependent film thickness was increased by the horizontal translation and decreased during the reverse of this translation caused by the multi-direction of the AP load during walking. The minimum film thickness of 12-20 nm was found at 0.4s and around the location at (95, 125) degrees. During the whole walking cycle both the average and centre film thickness were found obviously increased to a range of 40-65 nm, compared with the range of 25-55 nm under one load (vertical) and one motion (flexion-extension) condition, which suggested the lubrication in the current MOM hip implant was improved under 3D physiological loading and motion. This study suggested the lubrication performance especially the film thickness distribution should vary greatly under different operating conditions and the time and

  19. Research on Computer Integrated Manufacturing of Sheet Metal Parts for Lithium Battery

    Directory of Open Access Journals (Sweden)

    Pan Wei-Min

    2016-01-01

    Full Text Available Lithium battery has been widely used as the main driving force of the new energy vehicle in recent years. Sheet metal parts are formed by means of pressure forming techniques with the characteristics of light weight, small size and high structural strength. The sheet metal forming has higher productivity and material utilization than the mechanical cutting, therefore sheet metal parts are widely used in many fields, such as modern automotive industry, aviation, aerospace, machine tools, instruments and household appliances. In this paper, taking a complex lithium battery box as an example, the integrated manufacturing of sheet metal parts is studied, and the digital integrated design and manufacturing process system is proposed. The technology is studied such as sheet metal design, unfolding, sheet nesting and laser cutting, CNC turret punch stamping programming, CNC bending etc. The feasibility of the method is verified through the examples of products and the integrated manufacturing of sheet metal box is completed.

  20. Digital Aircraft Sheet Metal Part Manufacturing System and Its Key Technology

    Institute of Scientific and Technical Information of China (English)

    Wang; Junbiao; Liu; Chuang

    2007-01-01

    The architecture of digital sheet metal manufacturing system is proposed based on the classification of sheet metal manufacturing information.The essence of digital manufacturing is the definition,management and transfer of information,and the key technologies are brought forward and described.It is pointed out that knowledge-based manufacturing elements design is necessary to make digital technology efficient.The management of all kinds of sheet metal manufacturing element information is to build single source of manufacturing data.Multi-state model-based digital transfer and coordination method is designed to provide a foundation for digital manufacturing of aircraft sheet metal part.The application of digital sheet metal manufacturing is exemplified with an aircraft sheet metal part.The application result is compared to that of the traditional analog transfer technology.It is shown that the developed technology can improve part quality,shorten manufacturing time and lower manufacturing cost.

  1. Hard metal exposures. Part 2: Prospective exposure assessment.

    Science.gov (United States)

    Simcox, N J; Stebbins, A; Guffey, S; Atallah, R; Hibbard, R; Camp, J

    2000-04-01

    Hard metal exposures may precipitate lung disease in exposed workers. This article reports on a project investigating the relationship between local exhaust hood air flow levels and workplace hard metal exposures. Airborne cobalt, chromium, and cadmium exposure concentrations, and ventilation system function were monitored for three consecutive days prior to installation of three new ventilation systems, and then were followed monthly for one year. Work activities included wet and dry grinding of saw blades, brazing, welding, and setup. Work task exposures were highly variable over the period of the study. Ventilation air flows failed to meet design goals due to low total air volume and poor distribution; however, worker exposures to metals were controlled in most cases. Hood design, worker acceptance, and use of the hoods were as important in controlling exposures as were exhaust hood air flow levels.

  2. Ranking hospitals for outcomes in total hip replacement - administrative data with or without additional patient surveys? - Part 1: Administrative data

    Directory of Open Access Journals (Sweden)

    Dörning, Hans

    2007-03-01

    Full Text Available Background: Many hospital rankings rely on the frequency of adverse outcomes and are based on administrative data. In the study presented here, we tried to find out, to what extent available administrative data of German Sickness Funds allow for an adequate hospital ranking and compared this with rankings based on additional information derived from a patient survey. Total hip replacement was chosen as an example procedure. In part I of the publication, we present the results of the approach based on administrative data. Methods: We used administrative data from the AOK-Lower Saxony of the years 2000, 2001 and 2002. The study population comprised all beneficiaries, who received total hip replacement in the years 2000 or 2001. Performance indicators used where “critical incident (Mortality or revision” and “number of revisions” within the first year. Hospitals were ranked if they performed at least 20 procedures on AOK-beneficiaries in each of the two years. Multivariate modelling (logistic and poisson regression was used to estimate the performance indicators by case-mix variables (age, sex, co-diagnoses and hospital characteristics (hospital size, surgical volume. The actual ranking was based on these multivariate models, excluding hospital variables and adding dummy-variables for each hospital. Hospitals were ranked by their case-mix adjusted odds ratio or SMR respectively with respect to a pre-selected reference hospital. The resulting rankings were compared with each other, with regard to temporal stability, and the impact of case-mix variables.Results: About 4500 beneficiaries received total hip replacement in each year (n2000: 4482; n2001: 4579. The ranking included 65 hospitals. Comparing the years 2000 and 2001, the temporal stability of the rankings based on a single performance indicator was low (Spearman rang correlation coefficients 0.158 and 0.191. The agreement of rankings based on different performance indicators in the

  3. Prevalence of Failure due to Adverse Reaction to Metal Debris in Modern, Medium and Large Diameter Metal-on-Metal Hip Replacements--The Effect of Novel Screening Methods: Systematic Review and Metaregression Analysis.

    Directory of Open Access Journals (Sweden)

    Aleksi Reito

    Full Text Available Metal-on-metal (MoM hip replacements were used for almost a decade before adverse reactions to metal debris (ARMD were found to be a true clinical problem. Currently, there is a paucity of evidence regarding the usefulness of systematic screening for ARMD. We implemented a systematic review and meta-analysis to establish the prevalence of revision confirmed ARMD stratified by the use of different screening protocols in patients with MoM hip replacements. Five levels of screening were identified: no screening (level 0, targeted blood metal ion measurement and/or cross-sectional imaging (level 1, metal ion measurement without imaging (level 2, metal ion measurement with targeted imaging (level 3 and comprehensive screening (both metal ions and imaging for all; level 4. 122 studies meeting our eligibility criteria were included in analysis. These studies included 144 study arms: 100 study arms with hip resurfacings, 33 study arms with large-diameter MoM total hip replacements (THR, and 11 study arms with medium-diameter MoM THRs. For hip resurfacing, the lowest prevalence of ARMD was seen with level 0 screening (pooled prevalence 0.13% and the highest with level 4 screening (pooled prevalace 9.49%. Pooled prevalence of ARMD with level 0 screening was 0.29% and with level 4 screening 21.3% in the large-diameter MoM THR group. In metaregression analysis of hip resurfacings, level 4 screening was superior with regard to prevalence of ARMD when compared with other levels. In the large diameter THR group level 4 screening was superior to screening 0,2 and 3. These outcomes were irrespective of follow-up time or study publication year. With hip resurfacings, routine cross-sectional imaging regardless of clinical findings is advisable. It is clear, however, that targeted metal ion measurement and/or imaging is not sufficient in the screening for ARMD in any implant concepts. However, economic aspects should be weighed when choosing the preferred screening

  4. Two methods of tuning threshold voltage of bulk FinFETs with replacement high-k metal-gate stacks

    Science.gov (United States)

    Xu, Miao; Zhu, Huilong; Zhang, Yanbo; Xu, Qiuxia; Zhang, Yongkui; Qin, Changliang; Zhang, Qingzhu; Yin, Huaxiang; Xu, Hao; Chen, Shuai; Luo, Jun; Li, Chunlong; Zhao, Chao; Ye, Tianchun

    2017-03-01

    In this work, we propose two threshold voltage (VTH) tuning methods for bulk FinFETs with replacement high-k metal gate. The first method is to perform a vertical implantation into fin structure after dummy gate removal, self-aligned forming halo & punch through stop pocket (halo & PTSP) doping profile. The second method is to execute P+/BF2+ ion implantations into the single common work function (WF) layer in N-/P-FinFETs, respectively. These two methods have been investigated by TCAD simulations and MOS-capacitor experiments respectively, and then integrated into FinFET fabrication successfully. Experimental results show that the halo & PTSP doping profile can reduce VTH roll off and total variation. With P+/BF2+ doped WF layer, the VTH-sat shift -0.43 V/+1.26 V for N-FinFETs and -0.75 V/+0.11 V for P-FinFETs, respectively, with gate length of 500 nm. The proposed two methods are simple and effective for FinFET VTH tuning, and have potential for future application of massive production.

  5. Standard practice for process compensated resonance testing via swept sine input for metallic and Non-Metallic parts

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2010-01-01

    1.1 This practice describes a general procedure for using the process compensated resonance testing (PCRT) via swept sine input method to identify metallic and non-metallic parts’ resonant pattern differences that can be used to indentify parts with anomalies causing deficiencies in the expected performance of the part in service. This practice is intended for use with instruments capable of exciting, measuring, recording, and analyzing multiple whole body mechanical vibration resonant frequencies within parts exhibiting acoustical ringing in the audio, or ultrasonic, resonant frequency ranges, or both. PCRT is used in the presence of manufacturing process variance to distinguish acceptable parts from those containing significant anomalies in physical characteristics expected to significantly alter the performance. Such physical characteristics include, but are not limited to, cracks, voids, porosity, shrink, inclusions, discontinuities, grain and crystalline structure differences, density related anomalies...

  6. Metal fire implications for advanced reactors. Part 1, literature review.

    Energy Technology Data Exchange (ETDEWEB)

    Nowlen, Steven Patrick; Radel, Ross F.; Hewson, John C.; Olivier, Tara Jean; Blanchat, Thomas K.

    2007-10-01

    Public safety and acceptance is extremely important for the nuclear power renaissance to get started. The Advanced Burner Reactor and other potential designs utilize liquid sodium as a primary coolant which provides distinct challenges to the nuclear power industry. Fire is a dominant contributor to total nuclear plant risk events for current generation nuclear power plants. Utilizing past experience to develop suitable safety systems and procedures will minimize the chance of sodium leaks and the associated consequences in the next generation. An advanced understanding of metal fire behavior in regards to the new designs will benefit both science and industry. This report presents an extensive literature review that captures past experiences, new advanced reactor designs, and the current state-of-knowledge related to liquid sodium combustion behavior.

  7. Determination of heavy metals in soil and different parts of Diplazium esculentum (medicinal fern)

    Science.gov (United States)

    Jasim, Hind S.; Idris, Mushrifah; Abdullah, Aminah; Kadhum, A. A. H.

    2014-09-01

    Diplazium esculentum is a widely used medicinal fern in Malaysia and other regions worldwide. Heavy metals in plants should be determined because prolonged human intake of toxic trace elements, even at low doses, results in organ malfunction and causes chronic toxicity. Hence, substantial information should be obtained from plants that grow on soils containing high concentrations of heavy metals. This study aimed to determine the physicochemical characteristics of soil and heavy metal concentrations (Pb, Cr, Mn, Cu, and Zn) in different parts of D. esculentum and soil, which were collected from the fern garden of Universiti Kebangsaan Malaysia. Results showed that heavy metals were highly accumulated in D. esculentum roots.

  8. Laser Engineered Net Shaping (LENS(TM)): A Tool for Direct Fabrication of Metal Parts

    Energy Technology Data Exchange (ETDEWEB)

    Atwood, C.; Ensz, M.; Greene, D.; Griffith, M.; Harwell, L.; Reckaway, D.; Romero, T.; Schlienger, E.; Smugeresky, J.

    1998-11-05

    For many years, Sandia National Laboratories has been involved in the development and application of rapid prototyping and dmect fabrication technologies to build prototype parts and patterns for investment casting. Sandia is currently developing a process called Laser Engineered Net Shaping (LENS~) to fabricate filly dense metal parts dwectly from computer-aided design (CAD) solid models. The process is similar to traditional laser-initiated rapid prototyping technologies such as stereolithography and selective laser sintering in that layer additive techniques are used to fabricate physical parts directly from CAD data. By using the coordinated delivery of metal particles into a focused laser beam apart is generated. The laser beam creates a molten pool of metal on a substrate into which powder is injected. Concurrently, the substrate on which the deposition is occurring is moved under the beam/powder interaction zone to fabricate the desired cross-sectiwal geometry. Consecutive layers are additively deposited, thereby producing a three-dmensional part. This process exhibits enormous potential to revolutionize the way in which metal parts, such as complex prototypes, tooling, and small-lot production parts, are produced. The result is a comple~ filly dense, near-net-shape part. Parts have been fabricated from 316 stainless steel, nickel-based alloys, H13 tool steel, and titanium. This talk will provide a general overview of the LENS~ process, discuss potential applications, and display as-processed examples of parts.

  9. SCAI/AATS/ACC/STS operator and institutional requirements for transcatheter valve repair and replacement, Part III: Pulmonic valve.

    Science.gov (United States)

    Hijazi, Ziyad M; Ruiz, Carlos E; Zahn, Evan; Ringel, Richard; Aldea, Gabriel S; Bacha, Emile A; Bavaria, Joseph; Bolman, R Morton; Cameron, Duke E; Dean, Larry S; Feldman, Ted; Fullerton, David; Horlick, Eric; Mack, Michael J; Miller, D Craig; Moon, Marc R; Mukherjee, Debabrata; Trento, Alfredo; Tommaso, Carl L

    2015-07-01

    With the evolution of transcatheter valve replacement, an important opportunity has arisen for cardiologists and surgeons to collaborate in identifying the criteria for performing these procedures. Therefore, The Society for Cardiovascular Angiography and Interventions (SCAI), American Association for Thoracic Surgery (AATS), American College of Cardiology (ACC), and The Society of Thoracic Surgeons (STS) have partnered to provide recommendations for institutions to assess their potential for instituting and/or maintaining a transcatheter valve program. This article concerns transcatheter pulmonic valve replacement (tPVR). tPVR procedures are in their infancy with few reports available on which to base an expert consensus statement. Therefore, many of these recommendations are based on expert consensus and the few reports available. As the procedures evolve, technology advances, experience grows, and more data accumulate, there will certainly be a need to update this consensus statement. The writing committee and participating societies believe that the recommendations in this report serve as appropriate requisites. In some ways, these recommendations apply to institutions more than to individuals. There is a strong consensus that these new valve therapies are best performed using a Heart Team approach; thus, these credentialing criteria should be applied at the institutional level. Partnering societies used the ACC's policy on relationships with industry (RWI) and other entities to author this document (http://www.acc.org/guidelines/about-guidelines-and-clinical-documents). To avoid actual, potential, or perceived conflicts of interest due to industry relationships or personal interests, all members of the writing committee, as well as peer reviewers of the document, were asked to disclose all current healthcare-related relationships including those existing 12 months before the initiation of the writing effort. A committee of interventional cardiologists and

  10. Femtosecond Laser Post-Processing of Metal Parts Produced by Laser Additive Manufacturing

    Directory of Open Access Journals (Sweden)

    Mingareev Ilya

    2013-11-01

    Full Text Available High-repetition rate femtosecond laser radiation was utilized to improve surface quality of metal parts manufactured by laser additive techniques. This novel approach can be used to postprocess parts made of heat-sensitive materials, and to attain the designed net shape with micrometer precision.

  11. Numerical simulation-driven optimization of sheet metal drawing part shape

    Institute of Scientific and Technical Information of China (English)

    陈军; 石晓祥; 阮雪榆

    2003-01-01

    Numerical simulation and perturbation method were coupled into the iteration process for optimizing the sheet metal part stamping quality, by minimizing the risk of rupture, wrinkle and unstretched area. The optimization of the sheet metal drawing part surface was realized by adjusting the FEM node/element perturbation vector directions and values. The sweeping simplex algorithm was modified to better control the optimization process, and one-step simulation code was used to verify the new design formability. Finally, an autoauto fender drawing part shape optimization testified the proposed methods successfully.

  12. A European Renal Best Practice (ERBP) position statement on the Kidney Disease Improving Global Outcomes (KDIGO) Clinical Practice Guidelines on Acute Kidney Injury: part 2: renal replacement therapy.

    Science.gov (United States)

    Jörres, Achim; John, Stefan; Lewington, Andrew; ter Wee, Pieter M; Vanholder, Raymond; Van Biesen, Wim; Tattersall, James

    2013-12-01

    This paper provides an endorsement of the KDIGO guideline on acute kidney injury; more specifically, on the part that concerns renal replacement therapy. New evidence that has emerged since the publication of the KDIGO guideline was taken into account, and the guideline is commented on from a European perspective. Advice is given on when to start and stop renal replacement therapy in acute kidney injury; which modalities should be preferentially be applied, and in which conditions; how to gain access to circulation; how to measure adequacy; and which dose can be recommended.

  13. Patterns of risk of cancer in patients with metal-on-metal hip replacements versus other bearing surface types: a record linkage study between a prospective joint registry and general practice electronic health records in England.

    Directory of Open Access Journals (Sweden)

    Arief Lalmohamed

    Full Text Available BACKGROUND: There are concerns that metal-on-metal hip implants may cause cancer. The objective of this study was to evaluate patterns and timing of risk of cancer in patients with metal-on-metal total hip replacements (THR. METHODS: In a linkage study between the English National Joint Registry (NJR and the Clinical Practice Research Datalink (CPRD, we selected all THR surgeries (NJR between 2003 and 2010 (n = 11,540. THR patients were stratified by type of bearing surface. Patients were followed up for cancer and Poisson regression was used to derive adjusted relative rates (RR. RESULTS: The risk of cancer was similar in patients with hip resurfacing (RR 0.69; 95% Confidence Interval [CI] 0.39-1.22 or other types of bearing surfaces (RR 0.96; 95% CI 0.64-1.43 compared to individuals with stemmed metal-on-metal THR. The pattern of cancer risk over time did not support a detrimental effect of metal hip implants. There was substantial confounding: patients with metal-on-metal THRs used fewer drugs and had less comorbidity. CONCLUSIONS: Metal-on-metal THRs were not associated with an increased risk of cancer. There were substantial baseline differences between the different hip implants, indicating possibility of confounding in the comparisons between different types of THR implants.

  14. Vapor coating method using small-molecule organic surface modifiers to replace N-type metal oxide layers in inverted polymer solar cells.

    Science.gov (United States)

    Choi, Hyosung; Kim, Hak-Beom; Ko, Seo-Jin; Kim, Gi-Hwan; Kim, Jin Young

    2014-05-14

    We investigate a simple fabrication method for vapor coating small-molecule organic interlayers as replacements for metal oxide films. The interfacial layers, which serve both as both surface modifiers to reduce the substrate work function and electron selective layers, maximize light absorption within the active layer while improving electron transport and compatibility between the active layer and cathode, leading to a ∼22% enhancement in power conversion efficiency and similar air stability compared to devices using a ZnO layer.

  15. Mn in misch-metal based superlattice metal hydride alloy - Part 1 structural, hydrogen storage and electrochemical properties

    Science.gov (United States)

    Young, K.; Wong, D. F.; Wang, L.; Nei, J.; Ouchi, T.; Yasuoka, S.

    2015-03-01

    The structural, gaseous phase hydrogen storage, and electrochemical properties of a series of Mn-modified misch-metal based superlattice metal hydride alloys were investigated in part one of this two-part series of papers. X-ray diffraction analysis showed that these alloys are all multi-phased compositions with different abundances of AB2, AB3, A2B7, AB4, and AB5 phases. Substitution of Ni in the B-site by Mn promotes AB5 phase formation and decreases both gaseous phase and electrochemical capacities due to the reduction in the abundance of main hexagonal A2B7 phase. AC impedance and magnetic susceptibility measurement were employed to characterize the surface of Mn-free and Mn-modified alloys and show deterioration in surface catalytic ability as the Mn-content increases. Mn-modification adversely affected misch-metal based superlattice metal hydride alloy properties such as phase homogeneity, capacity, cycle stability, high-rate performance, and surface reaction.

  16. Occupational exposure to heavy metals in a metal-mechanical auto part manufacturing plant in Puebla, Mexico

    Directory of Open Access Journals (Sweden)

    Maria F Romero-Zarazua

    2015-01-01

    Full Text Available Aims: The concentration of Cd, Cr, Al and Pb present in inhalable air and deposited dust in a metal-mechanical parts manufacturing plant in Puebla, México were determined in order to assess the occupational exposure of workers in this plant. Materials and Methods: Fourteen air samples, six from the metal welding (MW and eight from the metal forming (MF areas, as well as metal dust accumulated on the floor of an auto part manufacturing plant, were collected. Sampling and analysis followed the National Institute for Occupational Safety and Health (NIOSH recommended methods for metals in inhalable air. Results: The average concentration of Al and Cd determined in a volume of inhalable air were adequate under NIOSH maximal exposure concentration limits in both sampled sites. Average concentrations of 0.001 (MF sampling site and 0.105 μg/L (MW sampling site for Al; 0.003 (MF and 0.0005 (MW μg/L for Cd, with respect to the NIOHS limits, 10 and 0.005 μg/L, for Al and Cd, respectively. However, Cr and Pb concentrations exceeded or were close to the limits recommended by NIOHS in both places (0.5 and 0.05 μg/L for Cr and Pb, respectively. Average concentrations of 0.345 (MF and 0.77 (MW μg/L for Cr and 0.153 (MF and 0.649 (MW μg/L for Pb, were determined. Levels of metal content (Cd, Cr and Pb in powder samples collected in both sampling sites were also higher than the suggested limits. Conclusion: The average concentration of Cr and Pb exceeded the limits recommended by the Occupational Safety and Health Administration and NIOSH for inhalable air in the workplace. Workers may be on risk of heavy metal occupational exposure. It is endorsed to implement safety measurements to avoid the breathing of contaminated air and also industrial level systems for dust and aerosol particle filtering or precipitation, altogether with stricter policies to regulate heavy metal exposure at these industries.

  17. Replacement names and nomenclatural comments for problematic species-group names in Europe's Neogene freshwater Gastropoda. Part 2

    Directory of Open Access Journals (Sweden)

    Thomas Neubauer

    2014-07-01

    Full Text Available In the course of a new database project on Miocene to Recent freshwater gastropods of Europe, a great many of primary and secondary homonyms were revealed. Such nomenclatural issues need clarification in order to avoid misunderstandings and wrong statements about geographical distributions and temporal ranges. The following 16 new names are introduced to replace existing homonyms: Theodoxus militaris jurisicpolsakae nom. n., Viviparus stevanovici nom. n., Melanopsis haueri ripanjensis nom. n., Melanopsis wolfgangfischeri nom. n., Micromelania ramacanensis nom. n., Pseudamnicola welterschultesi nom. n., Muellerpalia haszprunari nom. n., Muellerpalia pseudovalvatoides nom. n., Lithoglyphus gozhiki nom. n., Valvata heidemariae willmanni nom. n., Radix macaleti nom. n., Gyraulus okrugljakensis nom. n., Gyraulus rasseri nom. n., Gyraulus vrapceanus nom. n., Planorbarius halavatsi nom. n., and Segmentina mosbachensis nom. n. Additionally, six cases of homonyms are discussed that are not replaced by new names, because they are considered junior synonyms.

  18. Producing metal parts with selective laser sintering/hot isostatic pressing

    Science.gov (United States)

    Das, Suman; Wohlert, Martin; Beaman, Joseph J.; Bourell, David L.

    1998-12-01

    Selective laser sintering/hot isostatic pressing is a hybrid direct laser fabrication method that combines the strengths of both processes. Selective laser sintering can produce complexly shaped metal components with an integral, gas-impermeable skin. These components can then be directly post-processed to full density by containerless hot isostatic pressing. The use of the hybrid fabrication method, envisioned as a rapid, low-cost replacement for conventional metal-can hot isostatic pressing, is currently being studied for alloy 625 and Ti-6Al-4V alloys. The micro-structure and mechanical properties of selective-laser-sintering processed and hot isostatically pressed post-processed material compare well with those of conventionally processed material.

  19. Treatment of tunnel wash waters - experiments with organic sorbent materials. Part Ⅱ: Removal of toxic metals

    Institute of Scientific and Technical Information of China (English)

    PARUCH Adam M; ROSETH Roger

    2008-01-01

    In the first part of the article, the column and the bag experiments concerning removal of polycyclic aromatic hydrocarbons (PAHs) and nonpolar oil (NPO) from tunnel wash waters using organic sorbent materials have been described. This part presents the results of removal of toxic metals. The metals of concern (Al, As, Cd, Cr, Cu, Fe, Pb, Mo, Ni, and Zn) were selected based on the priority toxicant pollutants defined in surface water quality criteria. Concentrations of these metals in the collected effluents varied more than the concentrations of PAHs and NPO, and thus only metal contents were considered for statistical analyses. These analyses determined significant differences (P<0.05, P<0.01, and P<0.001) between the mean metal concentrations in the column effluents and those in applied wash water of road tunnel. The results obtained during both experiments revealed that the organic sorbents, and in particular their combination, removed toxic metals more effectively from wash water of road tunnel than from wash water of tunnel electrostatic filters. Among the investigated toxicants, Al and Fe showed the highest levels of reduction in the column experiment, 99.7% and 99.6%, respectively. The lowest reduction levels of 66.0% and 76.2% were found for Pb and Mo, respectively. The results of the bag experiment showed that even one day treatment of wash waters from tunnel electrostatic filters could reduce concentration of some toxicants by more than 70% (Al and Fe) and 80% (Cu).

  20. Heavy metals in urban soils of East St. Louis, IL. Part II: Leaching characteristics and modeling.

    Science.gov (United States)

    Kaminski, M D; Landsberger, S

    2000-09-01

    The city of East St. Louis, IL, has a history of abundant industrial activities including smelters of ferrous and non-ferrous metals, a coal-fired power plant, companies that produced organic and inorganic chemicals, and petroleum refineries. Following a gross assessment of heavy metals in the community soils (see Part I of this two-part series), leaching tests were performed on specific soils to elucidate heavy metal-associated mineral fractions and general leachability. Leaching experiments, including the Toxicity Characteristic Leaching Procedure (TLCP) and column tests, and sequential extractions, illustrated the low leachability of metals in East St. Louis soils. The column leachate results were modeled using a formulation developed for fly ash leaching. The importance of instantaneous dissolution was evident from the model. By incorporating desorption/adsorption terms into the source term, the model was adapted very well to the time-dependent heavy metal leachate concentrations. The results demonstrate the utility of a simple model to describe heavy metal leaching from contaminated soils.

  1. The effect of powder recycling in direct metal laser deposition on powder and manufactured part characteristics

    OpenAIRE

    Carroll, P A; Pinkerton, A. J.; Allen, J.; Syed, W. U. H.; Sezer, H. K.; Brown, P.; Ng, G; Scudamore, R.; Li, L.

    2006-01-01

    A potential way of improving the material efficiency and cost effectiveness of the Direct Metal Laser Deposition (DMLD) process is to take powder that is not utilised in each deposition attempt and re-use it in subsequent attempts (powder recycling). Currently, this is not widely implemented for fear of a detrimental effect on part quality. This study examines how powder recycling, using simple normalisation techniques, affects the powder and the quality of the deposited part. Work was conduc...

  2. Influence of part orientation on the geometric accuracy in robot-based incremental sheet metal forming

    Science.gov (United States)

    Störkle, Denis Daniel; Seim, Patrick; Thyssen, Lars; Kuhlenkötter, Bernd

    2016-10-01

    This article describes new developments in an incremental, robot-based sheet metal forming process (`Roboforming') for the production of sheet metal components for small lot sizes and prototypes. The dieless kinematic-based generation of the shape is implemented by means of two industrial robots, which are interconnected to a cooperating robot system. Compared to other incremental sheet metal forming (ISF) machines, this system offers high geometrical form flexibility without the need of any part-dependent tools. The industrial application of ISF is still limited by certain constraints, e.g. the low geometrical accuracy. Responding to these constraints, the authors present the influence of the part orientation and the forming sequence on the geometric accuracy. Their influence is illustrated with the help of various experimental results shown and interpreted within this article.

  3. High Performance Transfer Press for Precision Manufacturing of Micro Metal Parts

    DEFF Research Database (Denmark)

    Mahshid, Rasoul

    Micro forming technology has several notable benefits such as yielding remarkable accuracy, high production speed, material saving and good mechanical properties of formed parts which allows complex micro parts to be manufactured by this technology. There are also presses fabricated appropriately...... and handling concepts. The aim of this research primarily is to develop an integrated solution for micro metal forming based on a flexible tool with integrated handling operations. The study herein extends these finding by designing and implementation of a multi-step micro metal forming process based...... on the above developed handling solution including a fully instrumented flexible tool for micro metal forming with the above mentioned characteristics. For this research, the 1050 Aluminum Alloy was used for forming material while it is originally in the form of coil. This original stock was sectioned...

  4. Replacing a Missing Tooth

    Science.gov (United States)

    ... vessels in the tooth pulps are rather large. Drilling down these teeth for crowns may expose the ... porcelain replacement tooth is held in place by metal extensions cemented to the backs of the adjacent ...

  5. Reduction of Surface Roughness by Means of Laser Processing over Additive Manufacturing Metal Parts

    Directory of Open Access Journals (Sweden)

    Vittorio Alfieri

    2016-12-01

    Full Text Available Optimization of processing parameters and exposure strategies is usually performed in additive manufacturing to set up the process; nevertheless, standards for roughness may not be evenly matched on a single complex part, since surface features depend on the building direction of the part. This paper aims to evaluate post processing treating via laser surface modification by means of scanning optics and beam wobbling to process metal parts resulting from selective laser melting of stainless steel in order to improve surface topography. The results are discussed in terms of roughness, geometry of the fusion zone in the cross-section, microstructural modification, and microhardness so as to assess the effects of laser post processing. The benefits of beam wobbling over linear scanning processing are shown, as heat effects in the base metal are proven to be lower.

  6. Metals for bone implants. Part 1. Powder metallurgy and implant rendering.

    Science.gov (United States)

    Andani, Mohsen Taheri; Shayesteh Moghaddam, Narges; Haberland, Christoph; Dean, David; Miller, Michael J; Elahinia, Mohammad

    2014-10-01

    New metal alloys and metal fabrication strategies are likely to benefit future skeletal implant strategies. These metals and fabrication strategies were looked at from the point of view of standard-of-care implants for the mandible. These implants are used as part of the treatment for segmental resection due to oropharyngeal cancer, injury or correction of deformity due to pathology or congenital defect. The focus of this two-part review is the issues associated with the failure of existing mandibular implants that are due to mismatched material properties. Potential directions for future research are also studied. To mitigate these issues, the use of low-stiffness metallic alloys has been highlighted. To this end, the development, processing and biocompatibility of superelastic NiTi as well as resorbable magnesium-based alloys are discussed. Additionally, engineered porosity is reviewed as it can be an effective way of matching the stiffness of an implant with the surrounding tissue. These porosities and the overall geometry of the implant can be optimized for strain transduction and with a tailored stiffness profile. Rendering patient-specific, site-specific, morphology-specific and function-specific implants can now be achieved using these and other metals with bone-like material properties by additive manufacturing. The biocompatibility of implants prepared from superelastic and resorbable alloys is also reviewed.

  7. Lightweight concrete with Algerian limestone dust. Part II: study on 50% and 100% replacement to normal aggregate at timely age

    Directory of Open Access Journals (Sweden)

    S. Kitouni

    2015-12-01

    Full Text Available Abstract A control lightweight concrete (LWC mixture made with 50% and 100% of limestone as a replacement of coarse aggregates in weight was prepared. Limestone is used for economical and environmental concern. The concrete samples were cured at 65% relative humidity at 20 ºC. The compressive and flexural tensile strengths, elastic modulus and Poisson's ratio of hardened concrete were measured. Laboratory compressive and tensile strength tests results showed that LWC can be produced by the use of limestone. The aim of this study is twofold: one is to design a lightweight concrete with the use of limestone that will provide an advantage of reduction in dead weight of a structure; and second is to obtain a more economical LWC mixture with the use of limestone.

  8. Feasibility of asymmetric flow field-flow fractionation coupled to ICP-MS for the characterization of wear metal particles and metalloproteins in biofluids from hip replacement patients.

    Science.gov (United States)

    Loeschner, Katrin; Harrington, Chris F; Kearney, Jacque-Lucca; Langton, David J; Larsen, Erik H

    2015-06-01

    Hip replacements are used to improve the quality of life of people with orthopaedic conditions, but the use of metal-on-metal (MoM) arthroplasty has led to poor outcomes for some patients. These problems are related to the generation of micro- to nanosized metal wear particles containing Cr, Co or other elements, but the current analytical methods used to investigate the processes involved do not provide sufficient information to understand the size or composition of the wear particles generated in vivo. In this qualitative feasibility study, asymmetric flow field-flow fractionation (AF(4)) coupled with inductively coupled plasma mass spectrometry (ICP-MS) was used to investigate metal protein binding and the size and composition of wear metal particles present in serum and hip aspirates from MoM hip replacement patients. A well-established HPLC anion exchange chromatography (AEC) separation system coupled to ICP-MS was used to confirm the metal-protein associations in the serum samples. Off-line single particle ICP-MS (spICP-MS) analysis was used to confirm the approximate size distribution indicated by AF(4) of the wear particles in hip aspirates. In the serum samples, AF(4) -ICP-MS suggested that Cr was associated with transferrin (Tf) and Co with albumin (Alb) and an unidentified species; AEC-ICP-MS confirmed these associations and also indicated an association of Cr with Alb. In the hip aspirate sample, AF(4)-ICP-MS suggested that Cr was associated with Alb and Tf and that Co was associated with Alb and two unidentified compounds; AEC analysis confirmed the Cr results and the association of Co with Alb and a second compound. Enzymatic digestion of the hip aspirate sample, followed by separation using AF(4) with detection by UV absorption (280 nm), multi-angle light scattering and ICP-MS, suggested that the sizes of the Cr-, Co- and Mo-containing wear particles in a hip aspirate sample were in the range 40-150 nm. Off-line spICP-MS was used to confirm these

  9. Effects of different levels of Pumpkin (Cucurbita Pepo residue silage replacement with forage part of ration on male buffalo calves fattening performance

    Directory of Open Access Journals (Sweden)

    A. Hashemi

    2010-02-01

    Full Text Available An experiment was conducted to study the effects of replacing forage part of ration with different levels of Pumpkin (Cucurbita Pepo residual silage (PRS on fattening performance of male buffalo calves. Twenty Four calves with 203 + 27.9 Kg of BW fed experimental diets in a completely randomized design with 4 groups and 6 replicates. The four groups (1, 2, 3 and 4 included 0 (control, 20, 40 and 60 percent replacement of forage part of ration with PRS, respectively in basal diet. The results showed that dry matter intake (DMI was not significantly different between the groups. The highest and the lowest DMI were shown at the groups 1 and 4, respectively. Daily weight gain (DWG was not significantly different between the groups. The highest and the lowest DWG were shown at the groups 3 and 2, respectively. Feed conversion ratio (FCR was not significantly different between the groups. But the best FCR was obtained at group 1. It may conclude that forage part of ration can be substituted with PRS at 60 % level with no negative effects on male buffalo calves fattening performance.

  10. Cost-utility of metal-on-metal hip resurfacing compared to conventional total hip replacement in young active patients with osteoarthritis

    NARCIS (Netherlands)

    Heintzbergen, S.; Kulin, N.A.; IJzerman, M.J.; Steuten, L.M.G.; Werle, J.; Khong, H.; Marshall, D.A.

    2013-01-01

    Background: Metal-on-metal hip resurfacing arthroplasty (MoM HRA) has emerged as an alternative to total hip arthroplasty (THA) for younger active patients with osteoarthritis (OA). Birmingham hip resurfacing is the most common MoM HRA in Alberta, and is therefore compared with conventional THA. Obj

  11. A Study on Pre-processing Algorithms for Metal Parts Inspection

    Directory of Open Access Journals (Sweden)

    Haider Sh. Hashim

    2011-06-01

    Full Text Available Pre-processing is very useful in a variety of situations since it helps to suppress information that is not related to the exact image processing or analysis task. Mathematical morphology is used for analysis, understanding and image processing. It is an influential method in the geometric morphological analysis and image understanding. It has befallen a new theory in the digital image processing domain. Edges detection and noise reduction are a crucial and very important pre-processing step. The classical edge detection methods and filtering are less accurate in detecting complex edge and filtering various types of noise. This paper proposed some useful mathematic morphological techniques to detect edge and to filter noise in metal parts image. The experimental result showed that the proposed algorithm helps to increase accuracy of metal parts inspection system.

  12. MOTOR VEHICLE SAFETY: NHTSA’s Ability to Detect and Recall Defective Replacement Crash Parts Is Limited

    Science.gov (United States)

    2001-01-01

    recycled airbag systems. However, NHTSA’s defect identification and recall system has limitations. The key database used to identify unsafe parts...product safety recall . The two studies on the safety of recycled airbags that we identified concluded that they can be a potentially safe...GAO United States General Accounting OfficeReport to Congressional RequestersJanuary 2001 MOTOR VEHICLE SAFETY NHTSA’s Ability to Detect and Recall

  13. Ranking hospitals for outcomes in total hip replacement - administrative data with or without patient surveys? - Part 2: Patient survey and administrative data

    Directory of Open Access Journals (Sweden)

    Schäfer, Thomas

    2007-03-01

    Full Text Available Background: Many hospital rankings rely on the frequency of adverse outcomes and are based on administrative data. In the study presented here, we tried to find out, to what extent available administrative data of German Sickness Funds allow for an adequate hospital ranking and compared this with rankings based on additional information derived from a patient survey. Total hip replacement was chosen as an example procedure. In part II of the publication, we present the results of the approach based on administrative and patient-derived data. Methods: We used administrative data from a large health insurance (AOK-Lower Saxony of the year 2002 and from a patient survey. The study population comprised mainly beneficiaries, who received primary total hip replacement in the year 2002, were mailed a survey 6 month post-operatively and participated in the survey. Performance indicators used where “Revision”, “Complications” and “Change of functional impairment”. Hospitals were ranked if they performed at least 20 procedures on AOK-beneficiaries. Multivariate modelling (logistic regression and generalized linear models was used to estimate the performance indicators by case-mix variables (a.o. age, sex, co-morbidity, medical history and hospital characteristics (hospital size, surgical volume. The actual ranking was based on these multivariate models, excluding hospital variables and adding dummy-variables for each hospital. Hospitals were ranked by their case-mix adjusted odds ratio or Standardized Difference (SDR with respect to a pre-selected reference hospital. The resulting rankings were compared with each other and with regard to the impact of case-mix variables. Results: 4089 beneficiaries received primary total hip replacement in 2002. 3293 patients participated in the survey (80.5%. The ranking included 60 hospitals. The agreement of rankings based on different performance indicators in the same year was low to high (a correlation

  14. Predictable aesthetic replacement of a metal-ceramic crown using CAD/CAM technology: a case report.

    Science.gov (United States)

    Poticny, Daniel; Conrad, Robert

    2005-08-01

    The currently available CAD/CAM technologies present clinicians with various clinical benefits that include durability, marginal adaptation, and precision aesthetics. The clinical and laboratory procedures associated with these CAD/CAM systems differ from one another, and practitioners must understand the indications for each. Office-based systems, as demonstrated in the following case presentation, allow excellent results to be achieved in a single patient visit and provide a viable alternative for today's practice. This case report describes the associated sequences for a posterior CAD/CAM restoration. Learning Objectives This article discusses a protocol for the use of CAD/CAM restorations in the aesthetic replacement of defective posterior crowns. Upon reading this article, the reader should have: * Greater understanding of the in-office CAD/CAM procedures used to fabricate single-visit crowns. * Improved awareness of the bonding protocol used for these all-ceramic crowns.

  15. Ankle replacement

    Science.gov (United States)

    Ankle arthroplasty - total; Total ankle arthroplasty; Endoprosthetic ankle replacement; Ankle surgery ... You may not be able to have a total ankle replacement if you have had ankle joint infections in ...

  16. Knee Replacement

    Science.gov (United States)

    Knee replacement is surgery for people with severe knee damage. Knee replacement can relieve pain and allow you to ... Your doctor may recommend it if you have knee pain and medicine and other treatments are not ...

  17. Grading the severity of soft tissue changes associated with metal-on-metal hip replacements: reliability of an MR grading system

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, Helen; Cahir, John G.; Goodwin, Richard W. [Norfolk and Norwich University Hospital, Department of Radiology, Norwich, Norfolk (United Kingdom); Toms, Andoni Paul [Norfolk and Norwich University Hospital, Department of Radiology, Norwich, Norfolk (United Kingdom); Norwich Radiology Academy, Norwich (United Kingdom); Wimhurst, James; Nolan, John F. [Norfolk and Norwich University Hospital, Department of Orthopaedics, Norwich, Norfolk (United Kingdom)

    2011-03-15

    Metal-on-metal (MoM) soft tissue reactions or aseptic lymphocytic vasculitis-associated lesions (ALVAL) are being recognised using metal artefact reduction (MAR) MR with increasing frequency following the advent of second generation metal-on-metal bearings, but there is no standardised technique for reporting of MR appearances in this disease. The aim of this study was to measure the reliability of a grading system designed for scoring the severity of MoM disease on MRI. MRI examinations of 73 hips in 59 patients were retrospectively selected and then anonymised, randomised and reviewed by three independent observers (musculoskeletal radiologists). Each MR examination was scored as either A: normal, B: infection, C1: mild MoM disease, C2: moderate MoM disease or C3: severe MoM disease according to pre-defined criteria. Kappa correlation statistics were used to compare the observations. There was substantial agreement among all three observers; the correlation coefficient between the two most experienced observers was {kappa} = 0.78 [95% confidence intervals (CI): 0.68-0.88] and when compared with the least experienced observer coefficients were {kappa} = 0.69 (95% CI: 0.57-0.80) and {kappa} = 0.66 (95% CI: 0.54-0.78). The strongest correlation occurred for grades A, C2 and C3. The weakest correlations occurred for grades B and C1. The grading system described in this study is reliable for evaluating ALVAL in MoM prostheses using MR but is limited in differentiating mild disease from infection. (orig.)

  18. Electrocatalysts Prepared by Galvanic Replacement

    OpenAIRE

    Athanasios Papaderakis; Ioanna Mintsouli; Jenia Georgieva; Sotiris Sotiropoulos

    2017-01-01

    Galvanic replacement is the spontaneous replacement of surface layers of a metal, M, by a more noble metal, Mnoble, when the former is treated with a solution containing the latter in ionic form, according to the general replacement reaction: nM + mMnoblen+ → nMm+ + mMnoble. The reaction is driven by the difference in the equilibrium potential of the two metal/metal ion redox couples and, to avoid parasitic cathodic processes such as oxygen reduction and (in some cases) hydrogen evolution too...

  19. Optimizing fuel cell parts by using 3D screen printed metals

    Energy Technology Data Exchange (ETDEWEB)

    Studnitzky, Thomas [Fraunhofer-Institue for Manufacturing and Advanced Materials, Dresden (Germany). Dept. of Powder Metallurgy and Composite Materials; Strauss, Alexander [Centre for Fuel Cell Technology, Duisburg (Germany). Dept. of Microsystems

    2010-07-01

    Miniature fuel cells have the potential to extend the runtime of various portable applications. In this context, sufficient energy densities have to be achieved within a stack in order to build fuel cell systems competitive to established battery technologies. Metallic bipolar plates composed of stainless steels permit the construction of thin and mechanically robust cells. Moreover the utilisation of the presented manufacturing method enables a new freedom in design of Bipolar Plates and their integrated flow field structures for future improvements of cell efficiency. In this study different miniature PEM fuel cells have been designed and tested. Bases for their construction are micro structured plates composed of 316L stainless steel. This design can include very fine walls down to 60 {mu}m as well as undercuts, which is impossible with other manufacturing methods. These designs were adapted by Fraunhofer IFAM for the screen printing process. As a first result a proof of concept has been established for 3D screen printing as a method for the manufacturing of fuel cell bipolar elements. To this end, a modified screen printing process is used to manufacture 3-dimensional parts layer-on-layer by depositing a suitable metallic powder which is mixed with a binder. The resulting green parts might include closed channels and channel wall thicknesses may reach 80 {mu}m or less. The green parts are debindered and sintered in order to obtain purely metallic structures. The manufactured bipolar plates show promising electric behaviour. In the current state of the project, bipolar plates with undercuts and new materials combinations are in the centre of the investigations. (orig.)

  20. Tables of Replacement Parts for Vehicle Average Useful Life Study of Truck, 5 Ton, 6x6, M39A2 Series

    Science.gov (United States)

    1975-08-01

    Logistics ,O. ABSTRACT (Continue , l ree e-•’oe d it neoeeaty and td --, flt, by block numb..) This report contains tables of replacement parts developed...8217 n4c 000’’n>,. _j.u0.too ~0 ~ 0 0’(0 49 43 :; S Z) c ;u 0tLu .. .!J, Lu0LU Lu j w - 1- a L tD 4 o cm 0 L Z ..J P- 3 > ..2c ~ ~ ~ ~ .. W . L4 IL l I 4m...WI z v ൌmi WKn z-zO. M~ 43 Km K: 0KK X 44ft4az-4O:tm 0 4.~4kmu Wtm4. ac o K 4 3m 6m-30 4 .9mgemm.94mN I..e "Mre-NaPIP-aa:m.9lop 040.9m.4r.. FA#..Ne

  1. Effects of sequential replacement of -NH2 by -OH in the tripodal tetraamine tren on its acidity and metal ion coordinating properties.

    Science.gov (United States)

    Song, B; Reuber, J; Ochs, C; Hahn, F E; Lügger, T; Orvig, C

    2001-03-26

    The preparation is described of two modified derivatives of the tripodal tetraamine tren, 2-hydroxy-N,N-bis(2-aminoethyl)ethylamine, NN(2)O222, and 2-amino-N,N-bis(2-hydroxyethyl)ethylamine, NNO(2)222, in which one and two primary amines, respectively, have been replaced with hydroxyl groups. The aqueous acid-base and metal ion (Ni2+, Cu2+, Zn2+) coordination properties of these two compounds were studied by potentiometric, spectrophotometric, and NMR titrations. Two and three acidity constants, respectively, were determined for NNO(2)222 and NN(2)O222 by potentiometry. NMR titrations proved that deprotonation of the two OH residues in NNO(2)222, and of the one in NN(2)O222, corresponded to pK(a) > 14. Acidity constants related to deprotonation of the terminal primary amine functions were similar in both NNO(2)222 and NN(2)O222 (and to those in the parent compound tren), whereas deprotonation of the tertiary ammonium N atom had a very different acidity constant in each of these three compounds. Charge repulsion, polar effects, and intramolecular hydrogen bond formation are responsible for the discrepancy. Chelated diamine metal complexes for each ligand studied depended only on the basicity of the corresponding two amines, suggesting that the hydroxyl group interacted with the metal ion very weakly in acidic or neutral solutions. The ML2+ species further deprotonated to form M(L - H)+ and M(L - 2H) complexes, in which the protons are released from the coordinated OH group. A pM vs pH correlation showed that replacing an NH2 group with a OH group in tren or NN(2)O222 makes the resulting metal complex less stable. Electronic spectra showed that the Cu(II) complexes of both NNO(2)222 and NN(2)O222 adopted a square pyramidal geometry rather than a trigonal bipyramidal geometry. The X-ray crystal structure analysis of the zinc complex [Zn(OH)(mu-NNO(2)222 - H)Zn(NNO(2)222)]2+, as its [BF4]- salt, shows a dinuclear molecule containing two zinc ions, each coordinated in a

  2. Fact Sheet: Final Rule to Reduce Toxic Air Pollutants from Surface Coating of Miscellaneous Metal Parts and Products

    Science.gov (United States)

    This page contains an August 2003 fact sheet with information regarding the National Emission Standards for Miscellaneous Metal Parts and Products Surface Coating Operations. This document provides a summary of the information for this regulation.

  3. Knee joint replacement

    Science.gov (United States)

    ... of your kneecap. Your kneecap is called the patella. The replacement part is usually made from a ... long. Then your surgeon will: Move your kneecap (patella) out of the way, then cut the ends ...

  4. Variation in patterns of metal accumulation in thallus parts of Lessonia trabeculata (Laminariales; Phaeophyceae): implications for biomonitoring.

    Science.gov (United States)

    Sáez, Claudio A; Lobos, M Gabriela; Macaya, Erasmo C; Oliva, Doris; Quiroz, Waldo; Brown, Murray T

    2012-01-01

    Seaweeds are well known to concentrate metals from seawater and have been employed as monitors of metal pollution in coastal waters and estuaries. However, research showing that various intrinsic and extrinsic factors can influence metal accumulation, raises doubts about the basis for using seaweeds in biomonitoring programmes. The thallus of brown seaweeds of the order Laminariales (kelps) is morphologically complex but there is limited information about the variation in metal accumulation between the different parts, which might result in erroneous conclusions being drawn if not accounted for in the biomonitoring protocol. To assess patterns of individual metals in the differentiated parts of the thallus (blade, stipe, holdfast), concentrations of a wide range of essential and non-essential metals (Fe, Cr, Cu, Zn, Mn, Pb, Cd, Ni and Al) were measured in the kelp Lessonia trabeculata. Seaweeds were collected from three sampling stations located at 5, 30 and 60 m from an illegal sewage outfall close to Ventanas, Chile and from a pristine location at Faro Curaumilla. For the majority of metals the highest concentrations in bottom sediment and seaweed samples were found at the site closest to the outfall, with concentrations decreasing with distance from the outfall and at control stations; the exception was Cd, concentrations of which were higher at control stations. The patterns of metal concentrations in different thallus parts were metal specific and independent of sampling station. These results and the available literature suggest that biomonitoring of metals using seaweeds must take account of differences in the accumulation of metals in thallus parts of complex seaweeds.

  5. Variation in patterns of metal accumulation in thallus parts of Lessonia trabeculata (Laminariales; Phaeophyceae: implications for biomonitoring.

    Directory of Open Access Journals (Sweden)

    Claudio A Sáez

    Full Text Available Seaweeds are well known to concentrate metals from seawater and have been employed as monitors of metal pollution in coastal waters and estuaries. However, research showing that various intrinsic and extrinsic factors can influence metal accumulation, raises doubts about the basis for using seaweeds in biomonitoring programmes. The thallus of brown seaweeds of the order Laminariales (kelps is morphologically complex but there is limited information about the variation in metal accumulation between the different parts, which might result in erroneous conclusions being drawn if not accounted for in the biomonitoring protocol. To assess patterns of individual metals in the differentiated parts of the thallus (blade, stipe, holdfast, concentrations of a wide range of essential and non-essential metals (Fe, Cr, Cu, Zn, Mn, Pb, Cd, Ni and Al were measured in the kelp Lessonia trabeculata. Seaweeds were collected from three sampling stations located at 5, 30 and 60 m from an illegal sewage outfall close to Ventanas, Chile and from a pristine location at Faro Curaumilla. For the majority of metals the highest concentrations in bottom sediment and seaweed samples were found at the site closest to the outfall, with concentrations decreasing with distance from the outfall and at control stations; the exception was Cd, concentrations of which were higher at control stations. The patterns of metal concentrations in different thallus parts were metal specific and independent of sampling station. These results and the available literature suggest that biomonitoring of metals using seaweeds must take account of differences in the accumulation of metals in thallus parts of complex seaweeds.

  6. Formation of metal complex ions from amino acid in the presence of Li+, Na+ and K+ by electrospray ionization: metal replacement of hydrogen in the ligands.

    Science.gov (United States)

    Jang, Soonmin; Song, Min Ju; Kim, Hyunsik; Choi, Sung-Seen

    2011-05-01

    Alkali metal cations easily form complexes with proteins in biological systems; understanding amino acid clusters with these cations can provide useful insight into their behaviors at the molecular level including diagnosis and therapy of related diseases. For the purpose of characterization of basic interaction between amino acids and alkali metal, each of the 20 naturally occurring amino acids were ionized in the presence of lithium, sodium and potassium cations by electrospray ionization, and the resulting product ions were analyzed. We focus our attention on the gas phase alkali metal ion-proton exchanged complexes in current study, specifically complexes with serine, threonine, asparagine and glutamine, which share characteristic pattern unlike other amino acids. All amino acids generated [M + H](+) and [M + Na](+) ions, where M stands for the neutral amino acid. Serine, threonine, asparagine and glutamine generated cluster ions of [nM - nH + (n + 1)Na](+) and [nM - (n - 1)H + (n - 1)Na + K](+) , where n = 1-7. While the (M - H + Li) and (M - H + K) species were not observed, the neutral (M - H + Na) species formed by proton-sodium cation exchange had a highly stable cyclic structure with ketone and amine ligand sites, suggesting that (M - H + Na) serves as a building block in cluster ion formation. Cluster ion intensity distributions of [nM - nH + (n + 1)Na](+) and [nM - (n - 1)H + (n - 1)Na + K](+) showed a magic number at n = 3 and 4, respectively. Extensive B3LYP-DFT quantum mechanical calculations were carried out to elucidate the geometry and energy of the cluster ions, and they provided a reasonable explanation for the stability and structure of the cluster ions. Copyright © 2011 John Wiley & Sons, Ltd.

  7. 40 CFR Appendix B to Part 414 - Complexed Metal-Bearing Waste Streams

    Science.gov (United States)

    2010-07-01

    ... (including metallized) Organic pigments, miscellaneous lakes and toners Copper Disperse dyes Acid dyes Direct..., metallized/Azo dye + metal acetate Direct dyes, Azo Disperse dyes, Azo and Vat Organic pigment Green 7/Copper... halide + sodium-lead alloy Nickel Azo dyes, metallized/Azo dye + metal acetate Zinc Organic......

  8. Heavy metals accumulation in parts of paddy Oryza sativa L. grown in paddy field adjacent to ultrabasic soil

    Science.gov (United States)

    Hadif, Waqeed Mahdi; Rahim, Sahibin Abd; Sahid, Ismail; Bhuiyan, Atiqur Rahman; Ibrahim, Izyanti

    2015-09-01

    The present study was carried out to evaluate the accumulation and translocation of heavy metals from soil around the root zone to various parts of the paddy plant, namely the roots, stems, leaves and rice grains. This study was conducted in 2014 in paddy field adjacent to ultrabasic soil (field 1 and 2) located in Ranau, Sabah and one field (Field 3) taken as control located at the UKM experimental plot in peninsular of Malaysia. The plant species used in the present investigation is Paddy Batu. The heavy metals studied were Chromium (Cr), Iron (Fe) and Nickel (Ni). Heavy metals in soil and plant were extracted by wet digestion method. Heavy metals present in paddy plants and soils extract were measured using the ICP-MS. Heavy metals concentrations in the plant parts in descending order is the root > leaves > stem > rice grain. Lower concentration of all heavy metals in soils and plant parts was shown by the control site (Field 3) in UKM Bangi. Higher concentration of heavy metals occurred in the roots compared to other above ground parts (stem, leaves, and grains) of the paddy plant in all of the paddy field. The bioaccumulation factor (BAF) of heavy metals in all locations were recorded in descending order as Ni > Cr > Fe, the BAF values for all metals in the rice grains were low, whereas the BAF values were recorded high for Ni in all locations. The results also showed that Fe was the most predominant metal ion in the roots, followed by Ni then Cr.

  9. 40 CFR Appendix A to Part 438 - Typical Products in Metal Products and Machinery Sectors

    Science.gov (United States)

    2010-07-01

    ... Combustion Engines Measuring & Dispensing Pumps Mechanical Power Transmission Equipment Metal Working... Fasteners, Buttons, Needles & Pins Fluid Power Values & Hose Fittings Hand & Edge Tools Hand Saws & Saw... Forming Types Metal Shipping Barrels, Drums, Kegs, Pails Metal Stampings Power Driven Hand...

  10. Effect of femoral head size on the wear of metal on metal bearings in total hip replacements under adverse edge-loading conditions.

    Science.gov (United States)

    Al-Hajjar, Mazen; Fisher, John; Williams, Sophie; Tipper, Joanne L; Jennings, Louise M

    2013-02-01

    Metal-on-metal (MoM) bearings have shown low-wear rates under standard hip simulator conditions; however, retrieval studies have shown large variations in wear rates and mechanisms. High-wear in vivo has caused catastrophic complications and has been associated with steep cup-inclination angle (rotational malpositioning). However, increasing the cup-inclination angle in vitro has not replicated the increases in wear to the same extent as those observed in retrievals. Clinically relevant wear rates, patterns, and particles were observed in vitro for ceramic-on-ceramic bearings when microseparation (translational malpositioning) conditions were introduced into the gait cycle. In the present study, 28 and 36-mm MoM bearings were investigated under adverse conditions. Increasing the cup angle from 45° to 65° resulted in a significant increase in the wear rate of the 28 mm bearings. However, for the 36 mm bearings, head-rim contact did not occur under the steep cup-angle condition, and the wear rate did not increase. The introduction of microseparation to the gait cycle significantly increased the wear rate of the MoM bearings. Cup angle and head size did not influence the wear rate under microseparation conditions. This study indicated that high-in vivo wear rates were associated with edge loading due to rotational malpositioning such as high-cup-inclination angle and translational malpositioning that could occur due to several surgical factors. Translational malpositioning had a more dominant effect on the wear rate. Preclinical simulation testing should be undertaken with translational and rotational malpositioning conditions as well as standard walking cycle conditions defined by the ISO standard. Copyright © 2012 Wiley Periodicals, Inc.

  11. Accumulation of heavy metals in different parts of Russian thistle (Salsola tragus, Chenopodiaceae, a potential hyperaccumulator plant species

    Directory of Open Access Journals (Sweden)

    Dragović, R.

    2014-12-01

    Full Text Available Distribution and accumulation of 10 heavy metals was observed in plant parts of species S. tragus, a native representative of Serbian flora. According to high bioaccumulation values (BAF, more than a half of the analyzed elements were bioaccumulated in roots, as well as in the aerial part of the plant. Translocation factor (TF value was calculated, showing the ratio between the concentration of metals in roots and aerial parts of the plant. The results indicate that S. tragus may accumulate significant amounts of Cd, Co, Cr and Pb. Concentrations of some of the individual elements are shown to be statistically different depending on the sampled plant parts. Potential capacity of S. tragus for hyperaccumulation of heavy metals and possible utilization of this plant for phytoremediation is discussed.

  12. Behavior of a crack within a Dissimilar Metal Weld Part by using an Overlay Weld

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Kang Soo; Lee, Ho Jin; Lee, Bong Sang [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2009-05-15

    In recent years, the dissimilar metal welds, Alloy 82/182 welds, used to connect the stainless steel piping and low alloy steel or carbon steel components in a nuclear reactor piping system have experienced a cracking due to a primary water stress corrosion (PWSCC).It is well known that one reason for the cracking is the residual stress by the weld. But, it is difficult to estimate the weld residual stress exactly due to the many parameters for the welding process. In this paper, a Butt model weld specimen was manufactured and the residual stresses of the weld specimen were measured by the X-Ray method and a Hole Drilling Technique. These results were compared with the results of the Butt FEM Model to confirm the confidence of the FEM input. Also, an analysis of the Crack FEM models made by the ABAQUS Code was performed to estimate the behavior of a crack within a Dissimilar Metal Weld Part (DMWP) when an overlay weld on the DMWP was done.

  13. Metal on Metal Surface Replacement of Hip in Young Patients with Rheumatoid Arthritis of Aseptic Necrosis of Femoral Head%金属对金属人工全髋表面置换术的临床应用

    Institute of Scientific and Technical Information of China (English)

    夏庆; 陈统一; 姜晓幸; 姚振钧

    2001-01-01

    Purpose Present study investigated the role of metal on metal surface replacement of the hip in treating the young patients suffering rheumatoid arthritis or aseptic necrosis of femoral head. Methods Between Jan. 1995 and Dec. 1996.16 patients with 17 hips( rheumatoid arthritis 14, aseptic necrosis of femoral head 3) were resurfaced with hybrid metal on metal surface replacement prothesis. Patients were evaluated by self assessment form,hip function examination. Radiographs and Harris hip score. The average follow up time was 58.2 months. Results No patient received revision. Radiographs showed that all implants were in position satisfyingly. No loosening were revealed. The result of self assessment showed that patients were satisfied with 16 hips. The Harris score rose from preoperative 44(31 - 52) to postoperative 91 (79- 96). Conclusions The metal on metal surface replacement of hip is a useful treatment to release pain and keep the hip function of young patients suffering rheumatoid arthritis or aseptic necrosis of femoral head.%目的探讨金属对金属人工全髋表面置换术治疗类风湿性关节炎和股骨头无菌性坏死的临床价值。 方法从1995年1月至1996年12月,对16例患者17个髋关节(其中类风湿性关节炎14个,股骨头无菌性坏 死3个)行混合型金属对金属人工全髋表面置换术,术后行问卷调查、髋关节功能检查、X线和Harris评分分析, 平均随访58.2月。结果所有患者没有一例行翻修手术,X线显示所有表面置换假体植入位置满意,没有假体 松动、移位现象出现。问卷调查显示患者对16个髋关节的术后情况表示非常满意。Harris评分平均指数从术前 的44(31~52)分提高到术后的91(79~96)分。结论金属对金属人工全髋表面置换术不失为患类风湿性关节 炎和股骨头无菌性坏死的年青患者为保存关节功能,改善疼痛的一种有价值的治疗方法。

  14. Procesos de fabricación de metales celulares. Parte II: Vía sólida, deposición de metales, otros procesos

    Directory of Open Access Journals (Sweden)

    Fernández, P.

    2009-04-01

    Full Text Available At the first part of this paper review a description about cellular metal processes by liquid route, was made. In this second part, solid processes and metals deposition are described. In similar way, the different kind of processes in each case are reviewed; making a short description about the main parameters involved and the advantages and drawbacks in each of them.

    En la primera parte de esta revisión se realizó la descripción de los procesos empleados por vía líquida para la fabricación de metales celulares. En esta segunda parte, se describen los procesos correspondientes a la vía sólida y la deposición de metales. De igual manera, se revisan los diferentes métodos, en cada caso, haciendo una breve descripción de los principales parámetros involucrados y las ventajas y desventajas en cada uno de ellos.

  15. Vibroacoustic Optimization of Stiffening Ribs and Damping Material Distribution on Sheet Metal Parts

    Directory of Open Access Journals (Sweden)

    M. Carfagni

    2004-01-01

    Full Text Available Vehicle noise and vibration levels are basic parameters in passenger comfort. Both static and dynamic stiffness of sheet metal parts is commonly increased by means of stiffening ribs. Vibrations are also reduced by adding a layer of damping material on the floor, the roof, the firewall and other parts of the vehicle. In common practice the panels to be treated are ribbed according to criteria based on the designer’s experience, rather than on well defined design procedures and are uniformly covered by a layer of damping material. However, these are not efficient design solutions, especially with regard to the effectiveness of vibration reduction and to weight containment. In this paper a novel approach to achieve an optimal distribution of stiffening ribs and damping material will be presented. The proposed method is based on a Genetic Algorithm (G.A. procedure which takes into account both the vibroacoustic performance and the weight and cost reduction. A simple case study will be illustrated to demonstrate the capabilities of the developed procedure.

  16. Pulsed Current Gas Metal Arc Welding under Different Shielding and Pulse Parameters; Part 2: Behaviour of Metal Transfer

    National Research Council Canada - National Science Library

    Ghosh, P. K; Dorn, Lutz; Devakumaran, K; Hofmann, F

    2009-01-01

    ...) of pulsed current gas metal arc welding (P-GMAW) using mild steel filler wire have been studied with respect to change in pulse parameters under different gas shieldings of Ar+2%CO2 and Ar+18%CO2...

  17. Assembly of smart adaptronic piezo-metal composites by use of prefabricated batches of piezoceramic micro parts

    Science.gov (United States)

    Neugebauer, Reimund; Koriath, Hans-Joachim; Müller, Michael

    2013-04-01

    Current technologies for smart sheet metal part production base upon adhesive bonding of piezo-patches to the surface. A novel concept and process chain is the assembly of piezoceramic micro parts into local microstructures of metal sheets and subsequent joining by forming. This results in a full functional integration of the piezoceramic in the metal for sensor and actuator purposes. Mechanical coupling is non-positive without elastic interlayers and the electrical coupling is characterized by the metal being the ground electrode of the sensor. The paper describes the design, methods and tolerance management to overcome the challenges for reliable parallel microassembly and joining of prefabricated batches of 10 piezoceramic fibers with dimensions of 0.267 × 0.250 × 10 mm3 and nominal assembly clearances of +/-0.018 mm. The prefabrication of the batches is achieved by stacking and dicing of piezoceramic plates. Both the principles of precision machining and elastic averaging are applied for reliable production and joining of the batches. In experiments, equally spaced piezoceramic fibers within the batches were achieved. Prototypes were assembled and joined by forming achieving functional piezo-metal composites. With the given tolerances of the parts and the microstructure a statistical tolerance analysis has been performed in order to determine the maximum allowable position uncertainty of the microassembly system. An assembly yield of > 95% is expected for future scaled up high volume assembly of piezo-metal composites.

  18. Knee Replacement

    Science.gov (United States)

    ... need knee replacement surgery usually have problems walking, climbing stairs, and getting in and out of chairs. Some ... a total living space on one floor since climbing stairs can be difficult. Install safety bars or a ...

  19. Replacing penalties

    Directory of Open Access Journals (Sweden)

    Vitaly Stepashin

    2017-01-01

    Full Text Available УДК 343.24The subject. The article deals with the problem of the use of "substitute" penalties.The purpose of the article is to identify criminal and legal criteria for: selecting the replacement punishment; proportionality replacement leave punishment to others (the formalization of replacement; actually increasing the punishment (worsening of legal situation of the convicted.Methodology.The author uses the method of analysis and synthesis, formal legal method.Results. Replacing the punishment more severe as a result of malicious evasion from serving accused designated penalty requires the optimization of the following areas: 1 the selection of a substitute punishment; 2 replacement of proportionality is serving a sentence other (formalization of replacement; 3 ensuring the actual toughening penalties (deterioration of the legal status of the convict. It is important that the first two requirements pro-vide savings of repression in the implementation of the replacement of one form of punishment to others.Replacement of punishment on their own do not have any specifics. However, it is necessary to compare them with the contents of the punishment, which the convict from serving maliciously evaded. First, substitute the punishment should assume a more significant range of restrictions and deprivation of certain rights of the convict. Second, the perfor-mance characteristics of order substitute the punishment should assume guarantee imple-mentation of the new measures.With regard to replacing all forms of punishment are set significant limitations in the application that, in some cases, eliminates the possibility of replacement of the sentence, from serving where there has been willful evasion, a stricter measure of state coercion. It is important in the context of the topic and the possibility of a sentence of imprisonment as a substitute punishment in cases where the original purpose of the strict measures excluded. It is noteworthy that the

  20. Defective dental restorations: to repair or not to repair? Part 2: All-ceramics and porcelain fused to metal systems.

    Science.gov (United States)

    Blum, Igor R; Jagger, Daryll C; Wilson, Nairn H F

    2011-04-01

    With the increasing use of ceramics in restorative dentistry, and trends to extend restoration longevity through the use of minimal interventive techniques, dental practitioners should be familiar with the factors that may influence the decision either to repair or replace fractured metal-ceramic and all-ceramic restorations and, also, the materials and techniques available to repair these restorations. This second of two papers addresses the possible modes of failure of ceramic restorations and outlines indications and techniques in this developing aspect of restoration repair in clinical practice. The repair of metal-ceramic and all-ceramic restorations is a reliable low-cost, low-risk technique that may be of value for the management of loss or fracture of porcelain from a crown or bridge in clinical practice.

  1. Multiobjective Optimization for Fixture Locating Layout of Sheet Metal Part Using SVR and NSGA-II

    Directory of Open Access Journals (Sweden)

    Yuan Yang

    2017-01-01

    Full Text Available Fixture plays a significant role in determining the sheet metal part (SMP spatial position and restraining its excessive deformation in many manufacturing operations. However, it is still a difficult task to design and optimize SMP fixture locating layout at present because there exist multiple conflicting objectives and excessive computational cost of finite element analysis (FEA during the optimization process. To this end, a new multiobjective optimization method for SMP fixture locating layout is proposed in this paper based on the support vector regression (SVR surrogate model and the elitist nondominated sorting genetic algorithm (NSGA-II. By using ABAQUS™ Python script interface, a parametric FEA model is established. And the fixture locating layout is treated as design variables, while the overall deformation and maximum deformation of SMP under external forces are as the multiple objective functions. First, a limited number of training and testing samples are generated by combining Latin hypercube design (LHD with FEA. Second, two SVR prediction models corresponding to the multiple objectives are established by learning from the limited training samples and are integrated as the multiobjective optimization surrogate model. Third, NSGA-II is applied to determine the Pareto optimal solutions of SMP fixture locating layout. Finally, a multiobjective optimization for fixture locating layout of an aircraft fuselage skin case is conducted to illustrate and verify the proposed method.

  2. Esophageal replacement.

    Science.gov (United States)

    Kunisaki, Shaun M; Coran, Arnold G

    2017-04-01

    This article focuses on esophageal replacement as a surgical option for pediatric patients with end-stage esophageal disease. While it is obvious that the patient׳s own esophagus is the best esophagus, persisting with attempts to retain a native esophagus with no function and at all costs are futile and usually detrimental to the overall well-being of the child. In such cases, the esophagus should be abandoned, and the appropriate esophageal replacement is chosen for definitive reconstruction. We review the various types of conduits used for esophageal replacement and discuss the unique advantages and disadvantages that are relevant for clinical decision-making. Copyright © 2017 Elsevier Inc. All rights reserved.

  3. Development of procedures for the acquisition of metal Additive Manufacturing (AM) parts for use in the CSIR's wind tunnel models

    CSIR Research Space (South Africa)

    Johnston, C

    2015-11-04

    Full Text Available The first Additive Manufacturing (AM) non-load-bearing, client furnished part was used in the CSIR’s wind tunnels in 2007. The advent of metal-grown materials, and the acquisition of machines to grow them in South Africa, has made it feasible...

  4. Distribution of Heavy Metals in the Different Parts of Cerithidea Obtusa and the Relationships between Metal Distribution and Allometric Parameters of the Snail

    Directory of Open Access Journals (Sweden)

    Chee Kong YAP

    2010-07-01

    Full Text Available The intertidal gastropod, Cerithidea obtusa were obtained from Bako and Sematan (Sarawak and Deralik (Perak. Besides the shell, the snails were dissected into five different soft tissues. The soft tissues and the shell were then analysed for heavy metals. It was found that the highest concentrations of Cu (112 - 178 μg/g dw and Zn (117 - 161 μg/g dw were found in the tentacle; the highest concentrations of Cd (4.41 - 5.37 μg/g dw, Pb (53.2 - 63.8 μg/g dw and Ni (26.1 - 27.9 μg/g dw were found in the shell. On the other hand, the highest Fe concentrations (910 - 2921 μg/g dw were found in the operculum. The Spearman's correlation coefficient and multiple stepwise linear regression also revealed that the allometric parameters can influence the distribution of heavy metals in some of the different parts. From the present findings indicated that the heavy metals accumulated by the C. obtusa from the environment might affect its physical growth, which was shown by the negative correlations found between the metals in the different parts with the allometric parameters.

  5. CoCr wear particles generated from CoCr alloy metal-on-metal hip replacements, and cobalt ions stimulate apoptosis and expression of general toxicology-related genes in monocyte-like U937 cells

    Energy Technology Data Exchange (ETDEWEB)

    Posada, Olga M., E-mail: O.M.PosadaEstefan@leeds.ac.uk [Biomedical Engineering Department, University of Strathclyde, Wolfson Centre, Glasgow G4 0NW (United Kingdom); Gilmour, Denise [Pure and Applied Chemistry Department, University of Strathclyde, Thomas Graham Building, Glasgow G1 1XL (United Kingdom); Tate, Rothwelle J., E-mail: r.j.tate@strath.ac.uk [Strathclyde Institute for Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow G4 0RE (United Kingdom); Grant, M. Helen [Biomedical Engineering Department, University of Strathclyde, Wolfson Centre, Glasgow G4 0NW (United Kingdom)

    2014-11-15

    Cobalt-chromium (CoCr) particles in the nanometre size range and their concomitant release of Co and Cr ions into the patients' circulation are produced by wear at the articulating surfaces of metal-on-metal (MoM) implants. This process is associated with inflammation, bone loss and implant loosening and led to the withdrawal from the market of the DePuy ASR™ MoM hip replacements in 2010. Ions released from CoCr particles derived from a resurfacing implant in vitro and their subsequent cellular up-take were measured by ICP-MS. Moreover, the ability of such metal debris and Co ions to induce both apoptosis was evaluated with both FACS and immunoblotting. qRT-PCR was used to assess the effects on the expression of lymphotoxin alpha (LTA), BCL2-associated athanogene (BAG1), nitric oxide synthase 2 inducible (NOS2), FBJ murine osteosarcoma viral oncogene homolog (FOS), growth arrest and DNA-damage-inducible alpha (GADD45A). ICP-MS showed that the wear debris released significant (p < 0.05) amounts of Co and Cr ions into the culture medium, and significant (p < 0.05) cellular uptake of both ions. There was also an increase (p < 0.05) in apoptosis after a 48 h exposure to wear debris. Analysis of qRT-PCR results found significant up-regulation (p < 0.05) particularly of NOS2 and BAG1 in Co pre-treated cells which were subsequently exposed to Co ions + debris. Metal debris was more effective as an inducer of apoptosis and gene expression when cells had been pre-treated with Co ions. This suggests that if a patient receives sequential bilateral CoCr implants, the second implant may be more likely to produce adverse effects than the first one. - Highlights: • Effects of CoCr nanoparticles and Co ions on U937 cells were investigated. • Ions released from wear debris play an important role in cellular response, • Toxicity of Co ions could be related to NO metabolic processes and apoptosis. • CoCr particles were a more effective inducer of apoptosis after cell

  6. Treatment of tunnel wash waters--experiments with organic sorbent materials. Part II: Removal of toxic metals.

    Science.gov (United States)

    Paruch, Adam M; Roseth, Roger

    2008-01-01

    In the first part of the article, the column and the bag experiments concerning removal of polycyclic aromatic hydrocarbons (PAHs) and nonpolar oil (NPO) from tunnel wash waters using organic sorbent materials have been described. This part presents the results of removal of toxic metals. The metals of concern (Al, As, Cd, Cr, Cu, Fe, Pb, Mo, Ni, and Zn) were selected based on the priority toxicant pollutants defined in surface water quality criteria. Concentrations of these metals in the collected effluents varied more than the concentrations of PAHs and NPO, and thus only metal contents were considered for statistical analyses. These analyses determined significant differences (P experiments revealed that the organic sorbents, and in particular their combination, removed toxic metals more effectively from wash water of road tunnel than from wash water of tunnel electrostatic filters. Among the investigated toxicants, Al and Fe showed the highest levels of reduction in the column experiment, 99.7% and 99.6%, respectively. The lowest reduction levels of 66.0% and 76.2% were found for Pb and Mo, respectively. The results of the bag experiment showed that even one day treatment of wash waters from tunnel electrostatic filters could reduce concentration of some toxicants by more than 70% (Al and Fe) and 80% (Cu).

  7. Non-Metallic Biomaterials for Tooth Repair and Replacement. By Pekka Vallittu, Woodhead Publishing, 2013; 406 pages. Price £145.00/US$245.00/€175.00 ISBN 978-0-85709-244-1

    Directory of Open Access Journals (Sweden)

    Shu-Kun Lin

    2013-01-01

    Full Text Available 1. Discusses the properties of enamel and dentin and their role in adhesive dental restoration;2. Chapters also examine the wear properties of dental ceramics, glasses and bioactive glass ceramics for tooth repair and replacement;3. Dental composites and antibacterial restorative materials are also considered;4. Provides a concise overview of non-metallic biomaterials for dental clinicians, materials scientists and academic researchers alike.As the demand for healthy, attractive teeth increases, the methods and materials employed in restorative dentistry have become progressively more advanced. Non-metallic biomaterials for tooth repair and replacement focuses on the use of biomaterials for a range of applications in tooth repair and, in particular, dental restoration.

  8. An expert system for process planning of sheet metal parts produced on compound die for use in stamping industries

    Indian Academy of Sciences (India)

    SACHIN SALUNKHE; DEEPAK PANGHAL; SHAILENDRA KUMAR; H M A HUSSEIN

    2016-08-01

    Process planning of sheet metal part is an important activity in the design of compound die. Traditional methods of carrying out this task are manual, tedious, time-consuming, error-prone and experiencebased. This paper describes the research work involved in the development of an expert system for process planning of sheet metal parts produced on compound die. The proposed system is organized in six modules. For development of system modules, domain knowledge acquired from various sources of knowledge acquisition is refined and then framed in form of ‘IF-Then’ variety of production rules. System modules are coded in AutoLISP language and user interface is created using visual basic (VB). The system is capable to automate various activities of process planning including blank modeling, blank nesting, determining punch force required, election of clearance between punch and die, identifying sheet metal operations, and determining proper sequence of operations for manufacturing the part. The proposed system can be implemented on a PC having VB and AutoCAD software, therefore its low cost of implementation makes it affordable even for small scale sheet metal industries.

  9. Assessment of airborne heavy metal pollution using plant parts and topsoil.

    Science.gov (United States)

    Serbula, Snezana M; Miljkovic, Dusanka Dj; Kovacevic, Renata M; Ilic, Ana A

    2012-02-01

    Robinia pseudoacacia L. (Fabaceae) was evaluated as a possible bioindicator of airborne heavy metal pollution, which originates from mining and pyrometallurgical copper production in Bor (Eastern Serbia). Concentrations of Cu, Zn, Pb, Cd, As and Hg were determined in different plant organs (washed/unwashed leaves, branches, roots) and topsoil of R. pseudoacacia by ICP-AES and by AAS. Sampling was carried out during 2008 at ten selected sites distributed in five zones with different levels of pollution. Concentrations of Pb, Cd and Hg did not exceeded the maximum allowed concentration (MAC) in soils at any of the sampling sites. Cu and As were present only at two sites within the MAC, whereas Zn exceeded the MAC at two sampling sites. Although present in the soil, As, Cd and Hg were below limit of detection in all parts of R. pseudoacacia. The rest of the studied elements, collected at the sites closest to the copper smelter or in the directions of the prevailing winds, were found to be at high levels. The higest Cu and Zn concentrations were detected in branches of R. pseudoacacia at the site Krivelj in the rural zone (6418.2±355.4 mg kg⁻¹ and 4699.8±320.8 mg kg⁻¹, respectively). Pb was present in similar amounts in all parts of R. pseudoacacia in the concentration ranging from 4.9 ± 0.3 mg kg⁻¹ (in washed leaves, at tourist zone) to 66.9±5.3 mg kg⁻¹ (in roots, at urban-industrial zone). According to the mobility ratio, leaves and branches of R. pseudoacacia acted as excluders of Cu, Zn and Pb, except for the branches which acted as indicators of Zn. Although As is present in high concentrations in the air and topsoil of the examined area, results show that R. pseudoacacia is not a suitable indicator of environmental pollution with As. Copyright © 2011 Elsevier Inc. All rights reserved.

  10. Cysteine-grafted nonwoven geotextile: a new and efficient material for heavy metals sorption--Part B.

    Science.gov (United States)

    Vandenbossche, M; Vezin, H; Touati, N; Jimenez, M; Casetta, M; Traisnel, M

    2014-10-01

    The development of a new material designed to trap heavy metals from sediments or wastewater, based on a polypropylene non-woven covalently grafted with cysteine, has been reported in a previous paper (Part A). The non-woven was first functionalized with acrylic acid (AA) which is used as spacer, and then cysteine was immobilized on the substrate through covalent coupling in order to obtain the so-called PP-g-AA-cysteine. Some preliminary heavy metals adsorption tests gave interesting results: at 20 °C for 24 h and in a 1000 mg/L heavy metals solution, PP-g-AA-cysteine adsorbs 95 mg Cu/g PP (CuSO4 solution), 104 mg Cu/g PP (Cu(NO3)2 solution), 135 mg Pb/g PP (Pb(NO3)2 solution) and 21 mg Cr/g PP (Cr(NO3)3 solution). In this second part of the work, heavy metals sorption tests were carried out with Cu (II), Pb (II), and Cr (III) separately, in order to determine the sorption capacity of this new sorbent as a function of (i) the heavy metals concentration in the solution, (ii) the contact time with the solution, (iii) the pH and (iv) the ionic strength of the solution containing heavy metals. Moreover, the sorption capacity of PP-g-AA-Cysteine was studied using a polluted solution consisting of a mixture of these different heavy metals. An Electron Paramagnetic Resonance study was finally carried out in order to determine the coordination geometry in the environment of the copper trapped by the PP-g-AA-cysteine.

  11. Stripping chronopotentiometry at scanned deposition potential (SSCP). Part 5. Features of multi-metal systems

    NARCIS (Netherlands)

    Town, R.M.; Leeuwen, van H.P.

    2004-01-01

    This paper considers the mutual effects of metals on each other in scanned deposition potential stripping chronopotentiometry measurements (SSCP) on multi-metal systems. As compared to stripping voltammetry, depletive SSCP displays a certain resistance to the impact of intermetallic compounds, while

  12. Selected Metals in Sediments and Streams in the Oklahoma Part of the Tri-State Mining District, 2000-2006

    Science.gov (United States)

    Andrews, William J.; Becker, Mark F.; Mashburn, Shana L.; Smith, S. Jerrod

    2009-01-01

    The abandoned Tri-State mining district includes 1,188 square miles in northeastern Oklahoma, southeastern Kansas, and southwestern Missouri. The most productive part of the Tri-State mining district was the 40-square mile part in Oklahoma, commonly referred to as 'the Picher mining district' in north-central Ottawa County, Oklahoma. The Oklahoma part of the Tri-State mining district was a primary producing area of lead and zinc in the United States during the first half of the 20th century. Sulfide minerals of cadmium, iron, lead, and zinc that remained in flooded underground mine workings and in mine tailings on the land surface oxidized and dissolved with time, forming a variety of oxide, hydroxide, and hydroxycarbonate metallic minerals on the land surface and in streams that drain the district. Metals in water and sediments in streams draining the mining district can potentially impair the habitat and health of many forms of aquatic and terrestrial life. Lakebed, streambed and floodplain sediments and/or stream water were sampled at 30 sites in the Oklahoma part of the Tri-State mining district by the U.S. Geological Survey and the Oklahoma Department of Environmental Quality from 2000 to 2006 in cooperation with the U.S. Environmental Protection Agency, and the Quapaw and Seneca-Cayuga Tribes of Oklahoma. Aluminum and iron concentrations of several thousand milligrams per kilogram were measured in sediments collected from the upstream end of Grand Lake O' the Cherokees. Manganese and zinc concentrations in those sediments were several hundred milligrams per kilogram. Lead and cadmium concentrations in those sediments were about 10 percent and 0.1 percent of zinc concentrations, respectively. Sediment cores collected in a transect across the floodplain of Tar Creek near Miami, Oklahoma, in 2004 had similar or greater concentrations of those metals than sediment cores collected at the upstream end of Grand Lake O' the Cherokees. The greatest concentrations of

  13. Resection and Resolution of Bone Marrow Lesions Associated with an Improvement of Pain after Total Knee Replacement: A Novel Case Study Using a 3-Tesla Metal Artefact Reduction MRI Sequence.

    Science.gov (United States)

    Kurien, Thomas; Kerslake, Robert; Haywood, Brett; Pearson, Richard G; Scammell, Brigitte E

    2016-01-01

    We present our case report using a novel metal artefact reduction magnetic resonance imaging (MRI) sequence to observe resolution of subchondral bone marrow lesions (BMLs), which are strongly associated with pain, in a patient after total knee replacement surgery. Large BMLs were seen preoperatively on the 3-Tesla MRI scans in a patient with severe end stage OA awaiting total knee replacement surgery. Twelve months after surgery, using a novel metal artefact reduction MRI sequence, we were able to visualize the bone-prosthesis interface and found complete resection and resolution of these BMLs. This is the first reported study in the UK to use this metal artefact reduction MRI sequence at 3-Tesla showing that resection and resolution of BMLs in this patient were associated with an improvement of pain and function after total knee replacement surgery. In this case it was associated with a clinically significant improvement of pain and function after surgery. Failure to eradicate these lesions may be a cause of persistent postoperative pain that is seen in up to 20% of patients following TKR surgery.

  14. Electrocatalysts Prepared by Galvanic Replacement

    Directory of Open Access Journals (Sweden)

    Athanasios Papaderakis

    2017-03-01

    Full Text Available Galvanic replacement is the spontaneous replacement of surface layers of a metal, M, by a more noble metal, Mnoble, when the former is treated with a solution containing the latter in ionic form, according to the general replacement reaction: nM + mMnoblen+ → nMm+ + mMnoble. The reaction is driven by the difference in the equilibrium potential of the two metal/metal ion redox couples and, to avoid parasitic cathodic processes such as oxygen reduction and (in some cases hydrogen evolution too, both oxygen levels and the pH must be optimized. The resulting bimetallic material can in principle have a Mnoble-rich shell and M-rich core (denoted as Mnoble(M leading to a possible decrease in noble metal loading and the modification of its properties by the underlying metal M. This paper reviews a number of bimetallic or ternary electrocatalytic materials prepared by galvanic replacement for fuel cell, electrolysis and electrosynthesis reactions. These include oxygen reduction, methanol, formic acid and ethanol oxidation, hydrogen evolution and oxidation, oxygen evolution, borohydride oxidation, and halide reduction. Methods for depositing the precursor metal M on the support material (electrodeposition, electroless deposition, photodeposition as well as the various options for the support are also reviewed.

  15. Passivity of Metals in the Point Defect Model: Effect of Chloride [Part-III

    OpenAIRE

    Emmanuel, Bosco

    2012-01-01

    In this paper we study the effect of addition of chloride on the stability of the compact oxide layer pre-existing on a metal surface at a given impressed potential and . The variant of the point defect model (PDM)advanced by us recently is used to construct a theory for the chloride-induced build-up of metal vacancies at the metal-film interface and the chloride-induced dissolution of the compact oxide layer. Under the quasi-steady-state approximation the relevant moving boundary value probl...

  16. Spatial distribution and ecological risk assessment of heavy metal on surface sediment in west part of Java Sea

    Science.gov (United States)

    Effendi, Hefni; Wardiatno, Yusli; Kawaroe, Mujizat; Mursalin; Fauzia Lestari, Dea

    2017-01-01

    The surface sediments were identified from west part of Java Sea to evaluate spatial distribution and ecological risk potential of heavy metals (Hg, As, Cd, Cr, Cu, Pb, Zn and Ni). The samples were taken from surface sediment (Hg>Pb>Ni>Cu>As>Zn>Cr. Furthermore, the result of multivariate statistical analysis shows that correlation among heavy metals (As/Ni, Cd/Ni, and Cu/Zn) and heavy metals with Risk Index (Cd/Ri and Ni/Ri) had positive correlation in significance level p1). On the cluster analysis, Cd, Ni, Pb were identified as fairly high contaminations level (cluster 1), Hg as moderate contamination level (cluster 2) and Cu, Zn, Cr with lower contamination level (cluster 3).

  17. Invited Review Article: Review of post-process optical form metrology for industrial-grade metal additive manufactured parts.

    Science.gov (United States)

    Stavroulakis, P I; Leach, R K

    2016-04-01

    The scope of this review is to investigate the main post-process optical form measurement technologies available in industry today and to determine whether they are applicable to industrial-grade metal additive manufactured parts. An in-depth review of the operation of optical three-dimensional form measurement technologies applicable to metal additive manufacturing is presented, with a focus on their fundamental limitations. Looking into the future, some alternative candidate measurement technologies potentially applicable to metal additive manufacturing will be discussed, which either provide higher accuracy than currently available techniques but lack measurement volume, or inversely, which operate in the appropriate measurement volume but are not currently accurate enough to be used for industrial measurement.

  18. Invited Review Article: Review of post-process optical form metrology for industrial-grade metal additive manufactured parts

    Science.gov (United States)

    Stavroulakis, P. I.; Leach, R. K.

    2016-04-01

    The scope of this review is to investigate the main post-process optical form measurement technologies available in industry today and to determine whether they are applicable to industrial-grade metal additive manufactured parts. An in-depth review of the operation of optical three-dimensional form measurement technologies applicable to metal additive manufacturing is presented, with a focus on their fundamental limitations. Looking into the future, some alternative candidate measurement technologies potentially applicable to metal additive manufacturing will be discussed, which either provide higher accuracy than currently available techniques but lack measurement volume, or inversely, which operate in the appropriate measurement volume but are not currently accurate enough to be used for industrial measurement.

  19. FINAL TAILINGS OF METAL-WORKING PRODUCTION. Part 3. PHYSICO-MECHANICAL CHARACTERISTICS

    Directory of Open Access Journals (Sweden)

    O. M. Djakonov

    2011-01-01

    Full Text Available The indices of adhesion and friability of metal-containing tailings, their water absorbency and wettability and also abrasive characteristics of tailings with the purpose of prevention of contacting surfaces wear are studied.

  20. Comparison of Residual Stresses in Inconel 718 Simple Parts Made by Electron Beam Melting and Direct Laser Metal Sintering

    Science.gov (United States)

    Sochalski-Kolbus, L. M.; Payzant, E. A.; Cornwell, P. A.; Watkins, T. R.; Babu, S. S.; Dehoff, R. R.; Lorenz, M.; Ovchinnikova, O.; Duty, C.

    2015-03-01

    Residual stress profiles were mapped using neutron diffraction in two simple prism builds of Inconel 718: one fabricated with electron beam melting (EBM) and the other with direct laser metal sintering. Spatially indexed stress-free cubes were obtained by electrical discharge machining (EDM) equivalent prisms of similar shape. The (311) interplanar spacings from the EDM sectioned sample were compared to the interplanar spacings calculated to fulfill stress and moment balance. We have shown that applying stress and moment balance is a necessary supplement to the measurements for the stress-free cubes with respect to accurate stress calculations in additively manufactured components. In addition, our work has shown that residual stresses in electron beam melted parts are much smaller than that of direct laser metal sintered parts most likely due to the powder preheating step in the EBM process.

  1. Tensile Properties Characterization of AlSi10Mg Parts Produced by Direct Metal Laser Sintering via Nested Effects Modeling

    OpenAIRE

    Biagio Palumbo; Francesco Del Re; Massimo Martorelli; Antonio Lanzotti; Pasquale Corrado

    2017-01-01

    A statistical approach for the characterization of Additive Manufacturing (AM) processes is presented in this paper. Design of Experiments (DOE) and ANalysis of VAriance (ANOVA), both based on Nested Effects Modeling (NEM) technique, are adopted to assess the effect of different laser exposure strategies on physical and mechanical properties of AlSi10Mg parts produced by Direct Metal Laser Sintering (DMLS). Due to the wide industrial interest in AM technologies in many different fields, it is...

  2. A New Approach to Pectin Manufacture by Copper Method : Part 2. Preparation of Dry Metal-Pectin Complex

    OpenAIRE

    Kausar, Pervez; Nomura, Danji

    1981-01-01

    This study was part of an attempt to develop a disintegrated pectin manufacture process to utilize to its maximum already existing facilities at citrus juice plants as well as to cut down the energy and transport costs by maximum using the wet leached peel and transporting dry metal-pectin complex to a central pectin manufacture plant for further processing instead of transporting huge volume of pectin pomace. This type of approach was thought essential to prepare cost wise competiable pectin...

  3. Life time assessment and repair of dissimilar metal welds. Part 1; Livslaengdsbedoemning och reparation av blandsvetsskarvar. Etapp 1

    Energy Technology Data Exchange (ETDEWEB)

    Storesund, Jan; Borggreen, Kjeld

    2005-04-01

    Research on the performance of dissimilar metal welds in high temperature plant has been performed for many years. Nevertheless damages are frequent in such welds. In order to decrease the damage problems and make it possible to estimate residual lifetimes of dissimilar metal welds in our Nordic countries it is first essential to i) collect the knowledge in the literature and ii) map current dissimilar metal welds and their condition in Swedish and Danish plants. The present report describes this first part of the work. There is a comprehensive literature of she subject. Most work has been performed on ferritic/austenitic dissimilar welds. In Swedish and Danish plants the dominating type is ferritic/martensitic dissimilar welds. The damage mechanisms are about the same in the two types, creep is the dominating mechanism, but plant experience indicates that the ferritic/austenitic combination is more prone to damage than the ferritic/martensitic one. An important difference between the two types is that Ni-base weld metal generally prolongs the lifetime for ferritic/austenitic dissimilar welds whereas it shows an opposite effect in ferritic/martensitic ones. In the latter case use of a 5 % Cr weld metal seems to be the best choice but the experiences of such welds are limited. The mapping of dissimilar welds indicates that there are predominantly special kinds of welds which fail whereas ordinary butt welds and branch welds are relatively free from damage.

  4. Tensile Properties Characterization of AlSi10Mg Parts Produced by Direct Metal Laser Sintering via Nested Effects Modeling

    Directory of Open Access Journals (Sweden)

    Biagio Palumbo

    2017-02-01

    Full Text Available A statistical approach for the characterization of Additive Manufacturing (AM processes is presented in this paper. Design of Experiments (DOE and ANalysis of VAriance (ANOVA, both based on Nested Effects Modeling (NEM technique, are adopted to assess the effect of different laser exposure strategies on physical and mechanical properties of AlSi10Mg parts produced by Direct Metal Laser Sintering (DMLS. Due to the wide industrial interest in AM technologies in many different fields, it is extremely important to ensure high parts performances and productivity. For this aim, the present paper focuses on the evaluation of tensile properties of specimens built with different laser exposure strategies. Two optimal laser parameters settings, in terms of both process quality (part performances and productivity (part build rate, are identified.

  5. In vitro antimicrobial and antiprotozoal activities, phytochemical screening and heavy metals toxicity of different parts of Ballota nigra.

    Science.gov (United States)

    Ullah, Najeeb; Ahmad, Ijaz; Ayaz, Sultan

    2014-01-01

    The study was done to assess the phytochemicals (flavonoids, terpenoids, saponins, tannin, alkaloids, and phenol) in different parts (root, stem, and leaves) of Ballota nigra and correlated it to inhibition of microbes (bacteria and fungi), protozoan (Leishmania), and heavy metals toxicity evaluation. In root and stem flavonoids, terpenes and phenols were present in ethanol, chloroform, and ethyl acetate soluble fraction; these were found to be the most active inhibiting fractions against all the tested strains of bacteria, fungi, and leishmania. While in leaves flavonoids, terpenes, and phenols were present in ethanol, chloroform, and n-butanol fractions which were the most active fractions against both types of microbes and protozoan (leishmania) in in vitro study. Ethanol and chloroform fractions show maximum inhibition against Escherichia coli (17 mm). The phytochemical and biological screenings were correlated with the presence of heavy metals in selected plant Ballota nigra. Cr was found above permissible value (above 1.5 mg/kg) in all parts of the plant. Ni was above WHO limit in B. nigra root and leaves (3.35 ± 1.20 mg/kg and 5.09 ± 0.47 mg/kg, respectively). Fe was above permissible value in all parts of B. nigra (above 20 mg/kg). Cd was above permissible value in all parts of the plant (above 0.3 mg/kg). Pb was above WHO limit (above 2 mg/kg) in all parts of Ballota nigra.

  6. An experimental study on the springback in bending of w-shaped micro sheet-metal parts

    Directory of Open Access Journals (Sweden)

    Wan-Nawang Wan-Adlan

    2015-01-01

    Full Text Available In sheet-metal bending, defects relating to the component-forms such as springback are common. This is due to the elastic deflection that occurs in the material after the bending process takes place. The objective of the research is to study on the springback behaviour in micro sheet-metal parts. This paper reports an investigation concerning the influence of the material rolling direction on springback in the case of w-shaped bending parts. Micro bending parts using 316 L annealed stainless steel strips having thickness of 50 μm, 75 μm and 100 μm respectively were formed. The tensile and bending behaviours of the parts were observed through the experiment by considering the effect of rolling direction and size-effect related errors. The results revealed that various parameters influence the springback, such as thickness of the sheet, force applied, material rolling-direction and holding time during the sheet-deformation. The scale of the springback was also observed to be random among the parts made with a same sheet material.

  7. Localization of heavy metals immobilized on specific organic and mineral parts of a wood-derived biochar

    Science.gov (United States)

    Rees, Frédéric; Watteau, Françoise; Morel, Jean-Louis

    2013-04-01

    Biochar has been intensively investigated over recent years, not only as a promising carbon sequestration or fertilizing agent in soils but also as a possible new sorbent to remediate contaminated soils. A few studies have revealed its high potential for heavy metals immobilization depending on the nature of biochar and trace elements. The mechanisms behind this immobilization remain however unclear: some authors have hypothesized a high sorption capacity due to biochar large surface area while others have suggested that this immobilization is mainly due to soil pH increase. In particular, the distinction between heavy metals specific sorption in biochar pores and heavy metals precipitation in or outside biochar particles is often impossible to make while it is of primary importance to evaluate biochar ability to retain these pollutants on a long-time scale. In order to evaluate the main heavy metal immobilization effects on a standard biochar and to identify the most successful biochar parts of the sample, we examined biochar particles after heavy metals immobilization in batch experiments designed to mimic real chemical processes in soils. A biochar derived from hard and soft wood and pyrolyzed at about 450°C was put in contact with relatively low concentrations of heavy metals (Pb, Cu, Cd, Zn, Ni) in an initially acidic Ca(NO3)2 solution. Following a one-week adsorption and a one-week desorption step, we recovered the biochar particles and observed them using scanning electron microscopy coupled to energy dispersive x-ray spectroscopy, focusing especially on the changes in mineral phases and the location of each of the retained heavy metals on biochar particles. We were able to distinguish different structures in the biochar samples which were linked to the degree of pyrolysis and the exact nature of the raw wood biomass. We detected the presence of concentrated metals zones (e.g. lead) in specific locations of the organic particles depending on the original

  8. High performance metal/air fuel cells. Part 1. General review. [Li, Al, Ca, Cd, Mg

    Energy Technology Data Exchange (ETDEWEB)

    Cooper, J. F.

    1977-08-15

    Metal/air fuel cells are reviewed in terms of their potential application in electric vehicles. Attention is focused on those metals (light alkali and alkaline earth metals, and aluminum) which, in combination with oxygen, have theoretical energy densities (2--13 kWh/kg-metal) exceeding that of gasoline (utilized in automobiles at 2--3 kWh/kg). Lithium and aluminum have yielded 8- and 4 kWh/kg, respectively, in laboratory experimental cells. The slurry Zn/air system achieves 0.85 kWh/kg-Zn in prototype vehicle cells and is reviewed for comparison. Calcium can probably yield 1.8 kWh/kg-Ca, but its potential as a fuel has not yet been fully explored. The remaining metals appear to be unsuitable for use in aqueous electrolyte fuel cells. The discharge characteristics of lithium, aluminum, and (possibly) calcium/air cells indicate the potential for electric vehicles of the highway performance and minimum range (300 miles) of subcompact automobiles, rapid refueling for unlimited range extension, and the storage in the fuel cell of sufficient metal for ranges in excess of 1000 miles. Barriers to the concept are the economic necessity of recycling cell reaction products (except in the case of calcium), the expansion or creation of vast metal production industries, and the change-over of existing service station infrastructures to allow electric vehicle servicing. The energy efficiency of a transportation system using aluminum was estimated using data on the current aluminum production industry. The total estimated cost of ownership and operation of an aluminum/air cell was 3.0--3.6 cents/km. The relative rarity of lithium would complicate its use. 6 tables.

  9. Design and development of a layer-based additive manufacturing process for the realization of metal parts of designed mesostructure

    Science.gov (United States)

    Williams, Christopher Bryant

    Low-density cellular materials, metallic bodies with gaseous voids, are a unique class of materials that are characterized by their high strength, low mass, good energy absorption characteristics, and good thermal and acoustic insulation properties. In an effort to take advantage of this entire suite of positive mechanical traits, designers are tailoring the cellular mesostructure for multiple design objectives. Unfortunately, existing cellular material manufacturing technologies limit the design space as they are limited to certain part mesostructure, material type, and macrostructure. The opportunity that exists to improve the design of existing products, and the ability to reap the benefits of cellular materials in new applications is the driving force behind this research. As such, the primary research goal of this work is to design, embody, and analyze a manufacturing process that provides a designer the ability to specify the material type, material composition, void morphology, and mesostructure topology for any conceivable part geometry. The accomplishment of this goal is achieved in three phases of research: (1) Design---Following a systematic design process and a rigorous selection exercise, a layer-based additive manufacturing process is designed that is capable of meeting the unique requirements of fabricating cellular material geometry. Specifically, metal parts of designed mesostructure are fabricated via three-dimensional printing of metal oxide ceramic powder followed by post-processing in a reducing atmosphere. (2) Embodiment ---The primary research hypothesis is verified through the use of the designed manufacturing process chain to successfully realize metal parts of designed mesostructure. (3) Modeling & Evaluation ---The designed manufacturing process is modeled in this final research phase so as to increase understanding of experimental results and to establish a foundation for future analytical modeling research. In addition to an analysis of

  10. Cross-shear implementation in sliding-distance-coupled finite element analysis of wear in metal-on-polyethylene total joint arthroplasty: intervertebral total disc replacement as an illustrative application.

    Science.gov (United States)

    Goreham-Voss, Curtis M; Hyde, Philip J; Hall, Richard M; Fisher, John; Brown, Thomas D

    2010-06-18

    Computational simulations of wear of orthopaedic total joint replacement implants have proven to valuably complement laboratory physical simulators, for pre-clinical estimation of abrasive/adhesive wear propensity. This class of numerical formulations has primarily involved implementation of the Archard/Lancaster relationship, with local wear computed as the product of (finite element) contact stress, sliding speed, and a bearing-couple-dependent wear factor. The present study introduces an augmentation, whereby the influence of interface cross-shearing motion transverse to the prevailing molecular orientation of the polyethylene articular surface is taken into account in assigning the instantaneous local wear factor. The formulation augment is implemented within a widely utilized commercial finite element software environment (ABAQUS). Using a contemporary metal-on-polyethylene total disc replacement (ProDisc-L) as an illustrative implant, physically validated computational results are presented to document the role of cross-shearing effects in alternative laboratory consensus testing protocols. Going forward, this formulation permits systematically accounting for cross-shear effects in parametric computational wear studies of metal-on-polyethylene joint replacements, heretofore a substantial limitation of such analyses.

  11. Element Analysis of Ceramic Coatings under Spherical Indentation with Metallic Interlayer:Part Ⅱ Ring Crack

    Institute of Scientific and Technical Information of China (English)

    Minh-Quy LE; Seock-Sam KIM

    2006-01-01

    Spherical indentation of ceramic coatings with metallic interlayer was performed by means of axisymmetric finite element analysis(FEA). Two typical ceramic coatings with relatively high and low elastic modulus deposited on aluminum alloy and carbon steel were considered. The fracture mechanics of the ceramic coatings mechanisms due to occurrence of surface ring cracks extending traverse the coating thickness under spherical indentation are investigated within the framework of linear fracture mechanics. The J-integral associated to such cracks was computed. The evolution of J-integral vs the crack length and the indentation depth was studied. The effects of the interlayer, the coating and the substrate on the J-integral evolution were discussed. The results show that a suitable metallic interlayer can improve the fracture resistance of the coating systems under the same indentation conditions through reducing the J-integral.

  12. Impact assessment of biomass-based district heating systems in densely populated communities. Part II: Would the replacement of fossil fuels improve ambient air quality and human health?

    Science.gov (United States)

    Petrov, Olga; Bi, Xiaotao; Lau, Anthony

    2017-07-01

    To determine if replacing fossil fuel combustion with biomass gasification would impact air quality, we evaluated the impact of a small-scale biomass gasification plant (BRDF) at a university campus over 5 scenarios. The overall incremental contribution of fine particles (PM2.5) is found to be at least one order of magnitude lower than the provincial air quality objectives. The maximum PM2.5 emission from the natural gas fueled power house (PH) could adversely add to the already high background concentration levels. Nitrogen dioxide (NO2) emissions from the BRDF with no engineered pollution controls for NOx in place exceeded the provincial objective in all seasons except during summer. The impact score, IS, was the highest for NO2 (677 Disability Adjusted Life Years, DALY) when biomass entirely replaced fossil fuels, and the highest for PM2.5 (64 DALY) and CO (3 DALY) if all energy was produced by natural gas at PH. Complete replacement of fossil fuels by one biomass plant can result in almost 28% higher health impacts (708 DALY) compared to 513 DALY when both the current BRDF and the PH are operational mostly due to uncontrolled NO2 emissions. Observations from this study inform academic community, city planners, policy makers and technology developers on the impacts of community district heating systems and possible mitigation strategies: a) community energy demand could be met either by splitting emissions into more than one source at different locations and different fuel types or by a single source with the least-impact-based location selection criteria with biomass as a fuel; b) advanced high-efficiency pollution control devices are essential to lower emissions for emission sources located in a densely populated community; c) a spatial and temporal impact assessment should be performed in developing bioenergy-based district heating systems, in which the capital and operational costs should be balanced with not only the benefit to greenhouse gas emission

  13. Metallic nanoparticles and their medicinal potential. Part II: aluminosilicates, nanobiomagnets, quantum dots and cochleates.

    Science.gov (United States)

    Loomba, Leena; Scarabelli, Tiziano

    2013-09-01

    Metallic miniaturization techniques have taken metals to nanoscale size where they can display fascinating properties and their potential applications in medicine. In recent years, metal nanoparticles such as aluminium, silicon, iron, cadmium, selenium, indium and calcium, which find their presence in aluminosilicates, nanobiomagnets, quantum dots (Q-dots) and cochleates, have caught attention of medical industries. The increasing impact of metallic nanoparticles in life sciences has significantly advanced the production techniques for these nanoparticles. In this Review, the various methods for the synthesis of nanoparticles are outlined, followed by their physicochemical properties, some recent applications in wound healing, diagnostic imaging, biosensing, assay labeling, antimicrobial activity, cancer therapy and drug delivery are listed, and finally their toxicological impacts are revised. The first half of this article describes the medicinal uses of two noble nanoparticles - gold and silver. This Review provides further information on the ability of aluminum, silicon, iron, selenium, indium, calcium and zinc to be used as nanoparticles in biomedical sciences. Aluminosilicates find their utility in wound healing and antibacterial growth. Iron-oxide nanoparticles enhance the properties of MRI contrast agents and are also used as biomagnets. Cadmium, selenium, tellurium and indium form the core nanostructures of tiny Q-dots used in cellular assay labeling, high-resolution cell imaging and biosensing. Cochleates have the bivalent nano ions calcium, magnesium or zinc imbedded in their structures and are considered to be highly effective agents for drug and gene delivery. The aluminosilicates, nanobiomagnets, Q-dots and cochleates are discussed in the light of their properties, synthesis and utility.

  14. Heavy metals in some parts of Antarctica and the southern Indian Ocean

    Digital Repository Service at National Institute of Oceanography (India)

    Kureishy, T.W.; Sengupta, R.; Mesquita, A.; Sanzgiri, S.

    metals were determined in various samples. Zooplankton and krill were collected from 30°S to the Southern ocean. Lichens and moss were collected from the shores of glacial lakes around the Indian station Maitri in the Schirmacher Oasis. Sediments... and Ni levels also being appreciable (Table 3). The mosses and lichens growing on the shores of these lakes exhibited high Cu concentrations, but levels of Cd, Co and Ni were below detection limits in these samples. Feathers collected from moulting...

  15. [Estrogen replacement].

    Science.gov (United States)

    Søgaard, A J; Berntsen, G K; Magnus, J H; Tollan, A

    1998-02-10

    Recent research on long-term postmenopausal hormone replacement therapy (HRT) indicates a positive effect on both total mortality and morbidity. This has raised the question of widespread preventive long-term use of HRT. Possible side-effects and ideological issues related to preventive HRT have led to debate and uncertainty among health professionals, in the media, and in the population at large. In order to evaluate the level of knowledge about and attitudes towards HRT, a randomly selected group of 737 Norwegian women aged 16-79 was interviewed by the Central Bureau of Statistics. One in three women had received information about HRT in the last two years, mainly through weekly magazines and physicians. The proportion who answered the questions on knowledge correctly varied from 36% to 47%. Those who had been given information by a physician possessed accurate knowledge, had more positive attitudes towards HRT and were more willing to use HRT than women who had reviewed information through other channels. Women with a higher level of education were better informed and more knowledgeable than others, but were nevertheless more reluctant to use HRT than those who were less educated. The limited number of women who actually receive information on HRT, the low level of knowledge and the ambivalent attitudes toward HRT are a major challenge to the public health service.

  16. 40 CFR Appendix C to Part 438 - Metal-Bearing Operations Definitions

    Science.gov (United States)

    2010-07-01

    ... high concentrations using a chelating agent. This plates all areas of the part to a uniform thickness... treatment. The painting solution and rinses are batch discharged periodically to treatment. Photo Imaging...

  17. Preparation and application prospects metal containing biocorrectors as part of film coverings to maintain human health

    Directory of Open Access Journals (Sweden)

    L. P. Lazurina

    2016-01-01

    Full Text Available The study of mixed-ligand complex formation is important problem of coordination chemistry currently. The ligands of different nature within the domestic environment of the complex, have a mutual influence, changing the chemical properties of complexes (acid-base, oxidation-reduction, the rate of ligand substitution in the internal environment and their biological activity. According to the literature, the issues of mutual influence of ligands, which leads to a change in the reactivity of the complexes have been widely studied with the assistance of ligands of different nature. In recent years sharply increased interest in nanoobjects of different nature. This is due to the fact that many of the physical, chemical and biological properties of the nanoparticles significantly different characteristics from those of larger (macroscopic objects. The aim of the study was to examine the conditions of formation (ratio of components, acidity in solutions of mixed-metal biocomplexes copper. The studies have shown that the conditions of synthesis have significant impact on obtaining nanoparticles of zinc, copper and cobalt. The study of morphology and size of the resulting nanoparticles were performed on a scanning electron microscope Quanta FEG 650 in high vacuum (pressure in the chamber 8⋅10-3 to 3⋅10-3 Pa mode. The resulting nanoparticles are studied metal particles kanglomeraty complex structure of various shapes and sizes up to 200 nm, and the crystals are spherical shape sizes of 40–90 nm. It is shown that metal complexation with drugs (ligands leads to improvement of antimicrobial activity spectrum and expansion relative to the parent ligands, the studied biocomplexes are harmless biologically active substances, which can be recommended for further study.

  18. PREDICTION OF MECHANICAL PROPERTY OF WHISKER REINFORCED METAL MATRIX COMPOSITE: PART-Ⅰ. MODEL AND FORMULATION

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Based on study of strain distribution in whisker reinforced metal matrix composites, an explicit precise stiffness tensor is derived. In the present theory, the effect of whisker orientation on the macro property of composites is considered, but the effect of random whisker position and the complicated strain field at whisker ends are averaged. The derived formula is able to predict the stiffness modulus of composites with arbitrary whisker orientation under any loading condition. Compared with the models of micro-mechanics, the present theory is competent for modulus prediction of actual engineering composites. The verification and application of the present theory are given in a subsequent paper published in the same issue.

  19. Characterization & Modeling of Materials in Glass-To-Metal Seals: Part I

    Energy Technology Data Exchange (ETDEWEB)

    Chambers, Robert S. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Computer Science and Mechanics; Emery, John M. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Solid Mechanics; Tandon, Rajan [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Materials Reliability; Antoun, Bonnie R. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Mechanics of Materials; Stavig, Mark E. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Organic Materials Science; Newton, Clay S. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Materials Reliability

    2014-01-01

    To support higher fidelity modeling of residual stresses in glass-to-metal (GTM) seals and to demonstrate the accuracy of finite element analysis predictions, characterization and validation data have been collected for Sandia’s commonly used compression seal materials. The temperature dependence of the storage moduli, the shear relaxation modulus master curve and structural relaxation of the Schott 8061 glass were measured and stress-strain curves were generated for SS304L VAR in small strain regimes typical of GTM seal applications spanning temperatures from 20 to 500 C. Material models were calibrated and finite element predictions are being compared to measured data to assess the accuracy of predictions.

  20. Material Property Measurement of Metallic Parts using the INEEL Laser Ultrasonic Camera

    Energy Technology Data Exchange (ETDEWEB)

    K. L. Telschow; R. S. Schley; S. M. Watson; V. A. Deason

    1999-08-22

    Ultrasonic waves form a useful nondestructive evaluation (NDE) probe for determining physical, microstructural, and mechanical properties of materials and parts. Noncontacting laser ultrasonic methods are desired for remote measurements and on-line manufacture process monitoring. Researchers at the Idaho National Engineering & Environmental Laboratory (INEEL) have developed a versatile new method for detection of ultrasonic motion at surfaces. This method directly images, without the need for scanning, the surface distribution of subnanometer ultrasonic motion. By eliminating the need for scanning over large areas or complex parts, the inspection process can be greatly speeded up. Examples include measurements on parts with complex geometries through resonant ultrasound spectroscopy and of the properties of sheet materials determined through anisotropic elastic Lamb wave propagation. The operation and capabilities of the INEEL Laser Ultrasonic Camera are described along with measurement results.

  1. Material Property Measurement of Metallic Parts using the INEEL Laser Ultrasonic Camera

    Energy Technology Data Exchange (ETDEWEB)

    Telschow, Kenneth Louis; Deason, Vance Albert; Schley, Robert Scott; Watson, Scott Marshall

    1999-08-01

    Ultrasonic waves form a useful nondestructive evaluation (NDE) probe for determining physical, microstructural, and mechanical properties of materials and parts. Noncontacting laser ultrasonic methods are desired for remote measurements and on-line manufacture process monitoring. Researchers at the Idaho National Engineering & Environmental Laboratory (INEEL) have developed a versatile new method for detection of ultrasonic motion at surfaces. This method directly images, without the need for scanning, the surface distribution of subnanometer ultrasonic motion. By eliminating the need for scanning over large areas or complex parts, the inspection process can be greatly speeded up. Examples include measurements on parts with complex geometries through resonant ultrasound spectroscopy and of the properties of sheet materials determined through anisotropic elastic Lamb wave propagation. The operation and capabilities of the INEEL Laser Ultrasonic Camera are described along with measurement results.

  2. Test design description Volume 2, Part 1. IFR-1 metal fuel irradiation test (AK-181) element as-built data

    Energy Technology Data Exchange (ETDEWEB)

    Dodds, N. E.

    1986-06-01

    The IFR-1 Test, designated as the AK-181 Test Assembly, will be the first irradiation test of wire wrapped, sodium-bonded metallic fuel elements in the Fast Flux Test Facility (FFTF). The test is part of the Integral Fast Reactor (IFR) fuels program conducted by Argonne National Laboratory (ANL) in support of the Innovative Reactor Concepts Program sponsored by the US Department of Energy (DOE). One subassembly, containing 169 fuel elements, will be irradiated for 600 full power days to achieve 10 at.% burnup. Three metal fuel alloys (U-10Zr, U-8Pu-10Zr) will be irradiated in D9 cladding tubes. The metal fuel elements have a fuel-smeared density of 75% and each contains five slugs. The enriched zone contains three slugs and is 36-in. long. One 6.5-in. long depleted uranium axial blanket slug (DU-10Zr) was loaded at each end of the enriched zone. the fuel elements were fabricated at ANL-W and delivered to Westinghouse-Hanford for wirewrapping and assembly into the test article. This Test Design Description contains relevant data on compositions, densities, dimensions and weights for the cast fuel slugs and completed fuel elements. The elements conform to the requirements in MG-22, "Users` Guide for the Irradiation of Experiments in the FTR."

  3. Effective Work Function Engineering for Aggressively Scaled Planar and Multi-Gate Fin Field-Effect Transistor-Based Devices with High-k Last Replacement Metal Gate Technology

    Science.gov (United States)

    Veloso, Anabela; Aik Chew, Soon; Higuchi, Yuichi; Ragnarsson, Lars-Åke; Simoen, Eddy; Schram, Tom; Witters, Thomas; Van Ammel, Annemie; Dekkers, Harold; Tielens, Hilde; Devriendt, Katia; Heylen, Nancy; Sebaai, Farid; Brus, Stephan; Favia, Paola; Geypen, Jef; Bender, Hugo; Phatak, Anup; Chen, Michael S.; Lu, Xinliang; Ganguli, Seshadri; Lei, Yu; Tang, Wei; Fu, Xinyu; Gandikota, Srinivas; Noori, Atif; Brand, Adam; Yoshida, Naomi; Thean, Aaron; Horiguchi, Naoto

    2013-04-01

    This work reports on aggressively scaled replacement metal gate, high-k last devices (RMG-HKL), exploring several options for effective work function (EWF) engineering, and targeting logic high-performance and low-power applications. Tight low-threshold voltage (VT) distributions for scaled NMOS devices are obtained by controlled TiN/TiAl-alloying, either by using RF-physical vapor deposition (RF-PVD) or atomic layer deposition (ALD) for TiN growth. The first technique allows optimization of the TiAl/TiN thicknesses at the bottom of gate trenches while maximizing the space to be filled with a low-resistance metal; using ALD minimizes the occurrence of preferential paths, at gate sidewalls, for Al diffusion into the high-k dielectric, reducing gate leakage (JG). For multi-gate fin field-effect transistors (FinFETs) which require smaller EWF shifts from mid-gap for low-VT: 1) conformal, lower-JG ALD-TiN/TaSiAl; and 2) Al-rich ALD-TiN by controlled Al diffusion from the fill-metal are demonstrated to be promising candidates. Comparable bias temperature instability (BTI), improved noise behavior, and slightly reduced equivalent oxide thickness (EOT) are measured on Al-rich EWF-metal stacks.

  4. Potential of direct metal deposition technology for manufacturing thick functionally graded coatings and parts for reactors components

    Science.gov (United States)

    Thivillon, L.; Bertrand, Ph.; Laget, B.; Smurov, I.

    2009-03-01

    Direct metal deposition (DMD) is an automated 3D deposition process arising from laser cladding technology with co-axial powder injection to refine or refurbish parts. Recently DMD has been extended to manufacture large-size near-net-shape components. When applied for manufacturing new parts (or their refinement), DMD can provide tailored thermal properties, high corrosion resistance, tailored tribology, multifunctional performance and cost savings due to smart material combinations. In repair (refurbishment) operations, DMD can be applied for parts with a wide variety of geometries and sizes. In contrast to the current tool repair techniques such as tungsten inert gas (TIG), metal inert gas (MIG) and plasma welding, laser cladding technology by DMD offers a well-controlled heat-treated zone due to the high energy density of the laser beam. In addition, this technology may be used for preventative maintenance and design changes/up-grading. One of the advantages of DMD is the possibility to build functionally graded coatings (from 1 mm thickness and higher) and 3D multi-material objects (for example, 100 mm-sized monolithic rectangular) in a single-step manufacturing cycle by using up to 4-channel powder feeder. Approved materials are: Fe (including stainless steel), Ni and Co alloys, (Cu,Ni 10%), WC compounds, TiC compounds. The developed coatings/parts are characterized by low porosity (<1%), fine microstructure, and their microhardness is close to the benchmark value of wrought alloys after thermal treatment (Co-based alloy Stellite, Inox 316L, stainless steel 17-4PH). The intended applications concern cooling elements with complex geometry, friction joints under high temperature and load, light-weight mechanical support structures, hermetic joints, tubes with complex geometry, and tailored inside and outside surface properties, etc.

  5. DEVELOPMENT OF AN INNOVATIVE LASER SCANNER FOR GEOMETRICAL VERIFICATION OF METALLIC AND PLASTIC PARTS

    DEFF Research Database (Denmark)

    Carmignato, Simone; De Chiffre, Leonardo; Fisker, Rune

    2008-01-01

    and plastic parts. A first prototype of the novel measuring system has been developed, using laser triangulation. The system, besides ensuring the automatic reconstruction of complete surface models, has been designed to guarantee user-friendliness, versatility, reliability and speed. The paper focuses mainly...... dimensional measurements with adequate accuracy for most industrial requirements....

  6. 21 CFR 888.3320 - Hip joint metal/metal semi-constrained, with a cemented acetabular component, prosthesis.

    Science.gov (United States)

    2010-04-01

    ... cemented acetabular component, prosthesis. 888.3320 Section 888.3320 Food and Drugs FOOD AND DRUG..., prosthesis. (a) Identification. A hip joint metal/metal semi-constrained, with a cemented acetabular component, prosthesis is a two-part device intended to be implanted to replace a hip joint. The...

  7. 21 CFR 888.3330 - Hip joint metal/metal semi-constrained, with an uncemented acetabular component, prosthesis.

    Science.gov (United States)

    2010-04-01

    ... uncemented acetabular component, prosthesis. 888.3330 Section 888.3330 Food and Drugs FOOD AND DRUG..., prosthesis. (a) Identification. A hip joint metal/metal semi-constrained, with an uncemented acetabular component, prosthesis is a two-part device intended to be implanted to replace a hip joint. The...

  8. A New Approach for Handling of Micro Parts in Bulk Metal Forming

    DEFF Research Database (Denmark)

    Mahshid, Rasoul; Hansen, Hans Nørgaard; Arentoft, M.

    2012-01-01

    During last 10 years a lot of research has been done in micro forming processes. In spite of the challenges micro forming has in process, material properties, tooling technology and machines, micro forming technology yields remarkable accuracy and good mechanical properties with high rate...... of production [1]. This can fulfill the demands for mass production and miniaturization in industries and academic communities. According to the recent studies, topics related to materials, process and simulation have been investigated intensively and well documented. Machines, forming tools and handling...... systems are critical elements to complete micro forming technology for transferring knowledge to industries and toward miniature manufacturing systems (micro factory) [2]. Since most metal forming processes are multi stage, making a new handling system with high reliability on accuracy and speed...

  9. The share of non-metallic inclusions in high-grade steel for machine parts

    Directory of Open Access Journals (Sweden)

    T. Lipiński

    2010-10-01

    Full Text Available The aim of this work was to compare the differences in the purity steel in the dimensions of inclusion particles as dependent on various steel production processes. The experimental material consisted of semi-finished products of high-grade, medium-carbon constructional steel with: manganese, chromium, nickel, molybdenum and boron. The impurity content of steel was low as phosphorus and sulphur levels did not exceed 0.025%. The experimental material consisted of steel products obtained in three metallurgical processes: electric, electric with argon refining and oxygen converter with vacuum degassing of steel. Billet samples were collected to determine: chemical composition, relative volume of non-metallic inclusions, dimensions of impurities. The results were processed and presented in graphic form.

  10. Finite Element Analysis of Ceramic Coatings under Spherical Indentation with Metallic Interlayer: Part Ⅰ Uncracked Coatings

    Institute of Scientific and Technical Information of China (English)

    Minh-Quy LE; Seock-Sam KIM

    2006-01-01

    Spherical indentation of ceramic coatings with metallic interlayer was performed by means of axisymmetric finite element analysis (FEA). Two typical ceramic coatings with relatively high and low elastic modulus deposited on aluminum alloy and carbon steel were considered. Various combinations of indenter radius-coating thickness ratios and interlayer thickness-coating thickness ratios were used in the modeling. The effects of the interlayer, the coating and the substrate on the indentation behavior, such as the radial stress distribution along the coating surface as well as the coating interface, and the plastic deformation zone evolution in the substrate were investigated in connection with the above mentioned ratios. The coating cracking dominant modes were also discussed within the context of the peak tensile stresses on the coating surface and on the coating interface.

  11. Experimental Study of Residual Stresses in Metal Parts Obtained by Selective Laser Melting

    Science.gov (United States)

    Protasov, C. E.; Safronov, V. A.; Kotoban, D. V.; Gusarov, A. V.

    High local temperature gradients occur at additive manufacturing by selective laser melting of powder. This gives rise to undesirable residual stresses, deformations, and cracks. To understand how to control the formation of the residual stresses, a reliable method is necessary for measuring their distribution in the fabricated part. It is proposed to cut the part into thin plates and to reconstruct the residual stresses from the measured deformation of the plates. This method is tested on beams with square cross-section built from stainless steel. The beams were cut by electrical discharge machining and chemically etched. The obtained stress profile in vertical transversal direction slightly increases from the top to the bottom of the beam. This dependency is confirmed by numerical modeling. The measured stress profile agrees with the known results by other authors.

  12. PREDICTION OF MECHANICAL PROPERTY OF WHISKER REINFORCED METAL MATRIX COMPOSITE:PART-Ⅱ. VERIFICATION & APPLICATION

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The present paper continues the discussion in Part-I. Model and Formulation. Based on the theory proposed in Part-I, the formulae predicting stiffness moduli of the composites in some typical cases of whisker orientations and loading conditions are derived and compared with theoretical representatives in literatures, experimental measurement and commonly-used empirical formulae. It seems that (1) with whisker reinforcing and matrix-hardening considered, the present prediction is in well agreement with the experimental measurement; (2) the present theory can predict accurate moduli with the proper pre-calculated parameters; (3) the upper-bound and lower-bound of the present theory are just the predictions of equal strain theory and equal stress theory; (4) the present theory provides a physical explanation and theoretical base for the present commonly-used empirical formulae. Compared with the microscopic mechanical theories, the present theory is competent for modulus prediction of practical engineering composite in accuracy and simplicity.

  13. Feasibility of asymmetric flow field-flow fractionation coupled to ICP-MS for the characterization of wear metal particles and metalloproteins in biofluids from hip replacement patients

    DEFF Research Database (Denmark)

    Löschner, Katrin; Harrington, Chris F.; Kearney, Jacque-Lucca;

    2015-01-01

    or other elements, but the current analytical methods used to investigate the processes involved do not provide sufficient information to understand the size or composition of the wear particles generated in vivo. In this qualitative feasibility study, asymmetric flow field-flow fractionation (AF4) coupled...... and give an indication of particle size, providing useful pathological indices. As such, the methods indicate a new way forward for in vivo investigation of the processes which lead to tissue necrosis and hip loosening in patients with MoM hip replacements....

  14. SYNERGISTIC WOOD PRESERVATIVES FOR REPLACEMENT OF CCA

    Science.gov (United States)

    The objective of this project was to evaluate the potential synergistic combinations of environmentally-safe biocides as wood preservatives. These wood preservatives could be potential replacements for the heavy-metal based CCA.Didecyldimethylammonium chloride [DDAC] was...

  15. Clinical trial design principles and endpoint definitions for transcatheter mitral valve repair and replacement: part 2: endpoint definitions: A consensus document from the Mitral Valve Academic Research Consortium.

    Science.gov (United States)

    Stone, Gregg W; Adams, David H; Abraham, William T; Kappetein, Arie Pieter; Généreux, Philippe; Vranckx, Pascal; Mehran, Roxana; Kuck, Karl-Heinz; Leon, Martin B; Piazza, Nicolo; Head, Stuart J; Filippatos, Gerasimos; Vahanian, Alec S

    2015-08-01

    Mitral regurgitation (MR) is one of the most prevalent valve disorders and has numerous aetiologies, including primary (organic) MR, due to underlying degenerative/structural mitral valve (MV) pathology, and secondary (functional) MR, which is principally caused by global or regional left ventricular remodelling and/or severe left atrial dilation. Diagnosis and optimal management of MR requires integration of valve disease and heart failure specialists, MV cardiac surgeons, interventional cardiologists with expertise in structural heart disease, and imaging experts. The introduction of trans- catheter MV therapies has highlighted the need for a consensus approach to pragmatic clinical trial design and uniform endpoint definitions to evaluate outcomes in patients with MR. The Mitral Valve Academic Research Consortium is a collaboration between leading academic research organizations and physician-scientists specializing in MV disease from the United States and Europe. Three in-person meetings were held in Virginia and New York during which 44 heart failure, valve, and imaging experts, MV surgeons and interventional cardiologists, clinical trial specialists and statisticians, and representatives from the U.S. Food and Drug Administration considered all aspects of MV pathophysiology, prognosis, and therapies, culminating in a 2-part document describing consensus recommendations for clinical trial design (Part 1) and endpoint definitions (Part 2) to guide evaluation of transcatheter and surgical therapies for MR. The adoption of these recommendations will afford robustness and consistency in the comparative effectiveness evaluation of new devices and approaches to treat MR. These principles may be useful for regulatory assessment of new transcatheter MV devices, as well as for monitoring local and regional outcomes to guide quality improvement initiatives.

  16. Lotus corniculatus Crop Growth of in Crude Oil Contaminated Soil. Part 2 Biomass Metals Bioaccumulation

    Directory of Open Access Journals (Sweden)

    Florica Morariu

    2016-05-01

    Full Text Available Phytoremediation involves the ability of plants to remove pollutants and is a promise on low costs and efficient processes for cleaning oil polluted soil. Studies for phytoremediation of soils polluted with petroleum products were critical and were based on monitoring strategies implemented efficiency. These strategies are based on the necessity of treating polluted soil and plant cultivation. Treatment was performed with recycled materials, sewage sludge as fertilizer and fly ash as amendment. The studies took on the characteristics of qualitative and quantitative of Lotus corniculatus crops, plants tolerant to conditions for phytoremediation strategy implemented on polluted soils by 80.5 ± 3.9 g·kg-1 D.M. The use of sewage sludge mixed with fly ash resulted in formation of a layer covering the surface with vegetable grown by 85 - 94 % in July and by 67 - 83 % in August. In Lotus corniculatus crops have not been registered bioaccumulation of toxic metals according to legislation from Romania.

  17. METAL AND OVERGLAZE SINTERING IN A SINGLE FIRE APPLIED TO THE SPECIAL PARTS INDUSTRY

    Directory of Open Access Journals (Sweden)

    Alexandre Zaccaron

    2015-06-01

    Full Text Available In the present study, the characteristics of sintering of metal and overglaze in a single firing was verified. For that, it was collected 5 samples of overglaze from different glazing companies in the South region of Brazil, which were characterized by chemical analysis, coefficient of linear thermal expansion by dilatometry, and draining button (glaze melt flow test. Then, the overglazes were applied in the as-received condition and after milling for 5 and 10 minutes; the powders were characterized by particle size distribution analysis. Overglaze layers mixed with gold powder were applied to ceramic plates with mass of 0.5 and 1.0 g, and sintering was performed at four different temperatures (800°C, 850°C, 900°C and 950°C with 60 minutes firing cycle. Finally, the following tests were performed: visual analysis, light microscopy, colorimetry, and Mohs hardness. With the results of this work, samples with brightness and color characteristics close to the standard commercial product produced in multiple firings could be obtained. In the scratch resistance (Mohs hardness, the result was one point above the standard, indicating a better quality and durability of the material.

  18. Inelastic Deformation of Metal Matrix Composites. Part 1; Plasticity and Damage Mechanisms

    Science.gov (United States)

    Majumdar, B. S.; Newaz, G. M.

    1992-01-01

    The deformation mechanisms of a Ti 15-3/SCS6 (SiC fiber) metal matrix composite (MMC) were investigated using a combination of mechanical measurements and microstructural analysis. The objectives were to evaluate the contributions of plasticity and damage to the overall inelastic response, and to confirm the mechanisms by rigorous microstructural evaluations. The results of room temperature experiments performed on 0 degree and 90 degree systems primarily are reported in this report. Results of experiments performed on other laminate systems and at high temperatures will be provided in a forthcoming report. Inelastic deformation of the 0 degree MMC (fibers parallel to load direction) was dominated by the plasticity of the matrix. In contrast, inelastic deformations of the 90 degree composite (fibers perpendicular to loading direction) occurred by both damage and plasticity. The predictions of a continuum elastic plastic model were compared with experimental data. The model was adequate for predicting the 0 degree response; however, it was inadequate for predicting the 90 degree response largely because it neglected damage. The importance of validating constitutive models using a combination of mechanical measurements and microstructural analysis is pointed out. The deformation mechanisms, and the likely sequence of events associated with the inelastic deformation of MMCs, are indicated in this paper.

  19. Measurement of the solar neutrino capture rate with gallium metal, Part III

    CERN Document Server

    Abdurashitov, J N; Gorbachev, V V; Gurkina, P P; Ibragimova, T V; Kalikhov, A V; Khairnasov, N G; Knodel, T V; Mirmov, I N; Shikhin, A A; Veretenkin, E P; Yants, V E; Zatsepin, G T; Bowles, T J; Elliott, S R; Teasdale, W A; Nico, J S; Cleveland, B T; Wilkerson, J F

    2009-01-01

    The Russian-American experiment SAGE began to measure the solar neutrino capture rate with a target of gallium metal in December 1989. Measurements have continued with only a few brief interruptions since that time. We give here the experimental improvements in SAGE since its last published data summary in December 2001. Assuming the solar neutrino production rate was constant during the period of data collection, combined analysis of 168 extractions through December 2007 gives a capture rate of solar neutrinos with energy more than 233 keV of 65.4 (+3.1)(-3.0) (stat) (+2.6)(-2.8) (syst) SNU. The weighted average of the results of all three Ga solar neutrino experiments, SAGE, Gallex, and GNO, is now 66.1 +/- 3.1 SNU, where statistical and systematic uncertainties have been combined in quadrature. During the recent period of data collection a new test of SAGE was made with a reactor-produced 37Ar neutrino source. The ratio of observed to calculated rates in this experiment, combined with the measured rates in...

  20. [Prosthetic rehabilitation of partially edentulous patients: fixed - removable - combined? Metal - ceramics - all - ceramics? Implants? Anything goes! Part 1: two example cases of a combined fixed-removable restoration].

    Science.gov (United States)

    Schnabl, Dagmar

    2015-01-01

    After a careful diagnosis, treatment planning and pretreatment, two partially edentulous patients were restored partly by onlays, crowns and bridges, partly by removable prostheses. According to esthetic and functional demands all- and/or metal-ceramic restorations were used as well as cast frame prostheses with clasps or extracoronal attachments.

  1. Trace metals in soils of the main geomorphological units in the southwestern part of Western Siberia

    Science.gov (United States)

    Konstantinova, E. Yu

    2016-09-01

    Total concentrations of Ti, Cr, Mn, Ni, Cu, Zn, Rb, Sr, and Pb as well as soil granulometric texture were studied for three plot sites representing different geomorphologic units of the southwestern part of Western Siberia: periphery of the upland Tobolsky Mainland, Ishim plain, Turinskaya plain. Interregional difference in the relationship by and among the content of trace elements and particle size distribution of soil horizons is established. Thus, for the soils of Turinskaya plain such interrelations are not observed. For the soils of Ishim Plain moderate negative correlation between Pb concentrations and medium silt, as well as average positive correlations between Zn and fine sand, coarse sand and Pb are found. For the soils of the high terraces of the Irtish and periphery of Tobolsky Mainland interface zone moderate positive correlations between contents of Ti, Zn, Sr and fine sand, weak positive ones between Rb and medium sand, moderate negative ones between Zn and clay, Ti, Ni, Cu, Zn, Rb, Sr, and fine dust, Ti, Cu, Zn, Rb, Sr and medium silt are observed. Consequently, properties and genesis of local parent rocks are significant factors for distribution and accumulation of trace elements in the soils of the southern taiga; at the same time, the processes of bioaccumulation in thick humus horizons of dark gray soils and chernozems apparently play an important part in accumulation and migration of trace elements in forest-steppe soils of Ishim and Turinskaya plains.

  2. [Flow of molten metal in denture base in horizontal centrifugal casting procedure. (Part 2) Flow, inflow volume and casting time of molten metal passing through several sprues into model denture plate mold (author's transl)].

    Science.gov (United States)

    Okamura, H

    1978-10-01

    Two types of spruing methods were used in the casting of the denture type model pattern (thickness, 0.43 mm). Flow of molten metal in the mold was filmed by the improved system of Part 1. When three sprues were attached to the pattern vertically, molten metal passed through each sprue gate flowed being affected by the direction of gravity and revolution of casting machine, and gathered at the lower part of the mold. Next molten metal filled the mold from the lower part to the upper part. In this spruing type, molten metal turned its direction of flow several times. At the middle stage of casting, the inflow volume per unit time (inflow rate), v (mm3/10-2)s)was evaluated as v = 12.36 + 5.16A-0.16 A2 (A: total cross-sectional areas of sprues). The inflow rate increased with increase of the area of the sprues, but it saturated. When the main sprue and the subsprues were attached at the posterior border, the molten metal filled the mold from the lower part to the upper part quietly. In this spruing type, the casting mold was set facing its sprue gates downwards. The inflow rate at the middle stage of casting was evaluated as v = 21.05 + 1.79 C (C: the cross-sectional area of the main sprue). The inflow rate increased linearly with increase of the area of the main sprue.

  3. A Triaxial Failure Diagram to predict the forming limit of 3D sheet metal parts subjected to multiaxial stresses

    Science.gov (United States)

    Rastellini, F.; Socorro, G.; Forgas, A.; Onate, E.

    2016-08-01

    Accurate prediction of failure and forming limits is essential when modelling sheet metal forming processes. Since traditional Forming Limit Curves (FLCs) are not valid for materials subjected to triaxial loading, a new failure criterion is proposed in this paper based on the stress triaxility and the effective plastic strain accumulated during the history of material loading. Formability zones are identified inside the proposed Triaxial Failure Diagram (TFD). FLCs may be mapped into the TFD defining a new Triaxial Failure Curve, or it can be defined by triaxial failure experiments. Several TFD examples are validated and constrasted showing acceptable accuracy in the numerical prediction of forming failure/limit of 3D thick sheet parts.

  4. Metallic mercury uptake by catalase Part 1 In Vitro metallic mercury uptake by various kind of animals' erythrocytes and purified human erythrocyte catalase

    OpenAIRE

    劒持,堅志

    1980-01-01

    The uptake of metallic mercury was studied using erythrocytes with different catalase activities taken from various kind of animals. The results were: 1) The uptake of metallic mercury by erythrocytes paralleled the activity of catalase in the erythrocytes with and without hydrogen peroxide, suggesting that the erythrocyte catalase activity is related to the uptake of metallic mercury. 2) The uptake of metallic mercury occurred not only with purified human erythrocyte catalase but also with h...

  5. Measurement of the solar neutrino capture rate with gallium metal, part III

    Energy Technology Data Exchange (ETDEWEB)

    Elliott, Steven Ray [Los Alamos National Laboratory

    2008-01-01

    The Russian-American experiment SAGE began to measure the solar neutrino capture rate with a target of gallium metal in December 1989. Measurements have continued with only a few brief interruptions since that time. In this article we present the experimental improvements in SAGE since its last published data summary in December 2001. Assuming the solar neutrino production rate was constant during the period of data collection, combined analysis of 168 extractions through December 2007 gives a capture rate of solar neutrinos with energy more than 233 keY of 65.4{sup +3.1}{sub 3.0} (stat) {sup +2.6}{sub -2.8} (syst) SNU. The weighted average of the results of all three Ga solar neUlrino experiments, SAGE, Gallex, and GNO, is now 66.1 {+-} 3.1 SNU, where statistical and systematic uncertainties have been combined in quadrature. During the recent period of data collection a new test of SAGE was made with a reactor-produced {sup 37}Ar neutrino source. The ratio of observed to calculated rates in this experiment, combined with the measured rates in the three prior {sup 51}Cr neutrino-source experiments with Ga, is 0.88 {+-} 0.05. A probable explanation for this low result is that the cross section for neutrino capture by the two lowest-lying excited states in {sup 71}Ge has been overestimated. If we assume these cross sections are zero, then the standard solar model including neutrino oscillations predicts a total capture rate in Ga in the range of 63--67 SNU with an uncertainly of about 5%, in good agreement with experiment. We derive the current value of the pp neutrino flux produced in the Sun to be {phi}{sup {circle_dot}}{sub pp} = (6.1 {+-} 0.8) x 10{sup 10}/(cm{sup 2} s), which agrees well with the flux predicted by the standard solar model. Finally, we make several tests and show that the data are consistent with the assumption that the solar neutrino production rate is constant in time.

  6. Historical changes in trace metals and hydrocarbons in nearshore sediments, Alaskan Beaufort Sea, prior and subsequent to petroleum-related industrial development: Part I. Trace metals.

    Science.gov (United States)

    Naidu, A Sathy; Blanchard, Arny L; Misra, Debasmita; Trefry, John H; Dasher, Douglas H; Kelley, John J; Venkatesan, M Indira

    2012-10-01

    Concentrations of Fe, As, Ba, Cd, Cu, Cr, Pb, Mn, Ni, Sn, V and Zn in mud (drilling effluents. In Prudhoe Bay, concentration spikes of metals in ∼1988 presumably reflect enhanced metals deposition following maximum oil drilling in 1980s. In summary, the Alaskan Arctic nearshore has remained generally free of metal contamination despite petroleum-related activities in past 40 years.

  7. Metal Nitrides for Plasmonic Applications

    DEFF Research Database (Denmark)

    Naik, Gururaj V.; Schroeder, Jeremy; Guler, Urcan;

    2012-01-01

    Metal nitrides as alternatives to metals such as gold could offer many advantages when used as plasmonic material. We show that transition metal nitrides can replace metals providing equally good optical performance for many plasmonic applications.......Metal nitrides as alternatives to metals such as gold could offer many advantages when used as plasmonic material. We show that transition metal nitrides can replace metals providing equally good optical performance for many plasmonic applications....

  8. Reducing the effects of metal artefact using high keV monoenergetic reconstruction of dual energy CT (DECT) in hip replacements

    Energy Technology Data Exchange (ETDEWEB)

    Lewis, Mark [Norfolk and Norwich University Hospital, Norwich (United Kingdom); Norwich Radiology Academy, Norwich (United Kingdom); Reid, Karen [Norfolk and Norwich University Hospital, Norwich (United Kingdom); Toms, Andoni P. [Norfolk and Norwich University Hospital and University of East Anglia, Norwich (United Kingdom)

    2013-02-15

    The aim of this study was to determine whether high keV monoenergetic reconstruction of dual energy computed tomography (DECT) could be used to overcome the effects of beam hardening artefact that arise from preferential deflection of low energy photons. Two phantoms were used: a Charnley total hip replacement set in gelatine and a Catphan 500. DECT datasets were acquired at 100, 200 and 400 mA (Siemens Definition Flash, 100 and 140 kVp) and reconstructed using a standard combined algorithm (1:1) and then as monoenergetic reconstructions at 10 keV intervals from 40 to 190 keV. Semi-automated segmentation with threshold inpainting was used to obtain the attenuation values and standard deviation (SD) of the streak artefact. High contrast line pair resolution and background noise were assessed using the Catphan 500. Streak artefact is progressively reduced with increasing keV monoenergetic reconstructions. Reconstruction of a 400 mA acquisition at 150 keV results in reduction in the volume of streak artefact from 65 cm{sup 3} to 17 cm{sup 3} (74 %). There was a decrease in the contrast to noise ratio (CNR) at higher tube voltages, with the peak CNR seen at 70-80 keV. High contrast spatial resolution was maintained at high keV values. Monoenergetic reconstruction of dual energy CT at increasing theoretical kilovoltages reduces the streak artefact produced by beam hardening from orthopaedic prostheses, accompanied by a modest increase in heterogeneity of background image attenuation, and decrease in contrast to noise ratio, but no deterioration in high contrast line pair resolution. (orig.)

  9. Replacing lactose from calf milk replacers : effects on digestion and post-absorptive metabolism

    NARCIS (Netherlands)

    Gilbert, M.S.

    2015-01-01

    Summary PhD thesis Myrthe S. Gilbert Replacing lactose from calf milk replacers – Effects on digestion and post-absorptive metabolism Veal calves are fed milk replacer (MR) and solid feed. The largest part of the energy provided to veal calves originates from

  10. Trends in atmospheric heavy metals abundances over the Russian part of EMEP region in 1990-2012

    Science.gov (United States)

    Gromov, Sergey A.; Konkova, Elizaveta S.

    2016-04-01

    The European part of Russia is covered by two atmospheric environment monitoring networks established in the 1970s-1980s to monitor and evaluate anthropogenic pollution of regional/background natural environment. These are EMEP - European Monitoring and Evaluation Program of transboundary atmospheric pollutant transmission (under the UN ECE Convention on Long-Range Transboundary Air Pollution) and IBMoN - Integrated Background Monitoring Network of environmental toxic pollution (prior to 1990 under the UNEP/GEMS supervision, mostly for East European countries). IGCE laboratories operate as analytical centers for both networks. Historically, IBMoN was partly implemented at EMEP sites to support this international program with additional (optional) data. IBMoN datasets were selected for analysis of atmospheric heavy metal trends in the Russian territory of EMEP region for the last twenty three years due to more intensive operation up to now [1, 2]. Atmospheric heavy metals are collected at the remote sites with the air samples of atmospheric aerosols deposited on Petryanov's cellulose acetate filters through high-volume pumping during 24 hours. To measure lead and cadmium content, filters are transferred into the solution to determine total amounts by the Atomic Absorption Spectroscopy (AAS) with flameless atomization. Precipitation samples (collected monthly with acidic preserving) are directly injected into the AAS detection module after filtering. The sampling procedure, special processing and analytical techniques allow us to measure concentrations at substantially low levels [3, 2]. In this study we investigate the long term trends of lead and cadmium in air and precipitation at two stations, viz. Astrakhan Biosphere Reserve (46°N, 49°E) and Danki (Oka-Terrace Biosphere Reserve, 54.9°N, 37.8°E). Following the EMEP general recommendations, the evaluation was done for two continuous periods covering 1990-2001 and 2002-2012, respectively. We apply the common

  11. 金属橡胶角度人工颈椎间盘植入后颈椎的稳定性变化%Cervical stability changes following metal rubber cervical disc replacement

    Institute of Scientific and Technical Information of China (English)

    柏传毅; 卫文博; 党晓谦; 王坤正

    2015-01-01

    BACKGROUND:Previous studies designed and made titanium metal rubber cervical disc prosthesis, and performed feasible studies on its effect on movement and stress distribution by replicating intervertebral discs. OBJECTIVE:To further observe the changes in the stability of goat cervical vertebra after metal rubber cervical disc replacement. METHODS:Nine goats were randomly divided into experimental group (n=6) and normal control group (n=3). Goats in the experimental group received metal rubber cervical disc replacement at C4/5segment. Goats in the normal control group did not receive any treatment. Radiographic data at anteroposterior and lateral position, hyperextension and excessive flexion were taken to measure intervertebral height, range of motion and intervertebral angle at C4/5 segment before operation, immediately, 4, 8, 12 weeks after operation. Subsequently, slicing and embedding of hard tissue at surgical segment, picric acid-acid fuchsin staining and scanning electron microscopy were conducted.RESULTS AND CONCLUSION:No significant difference in the intervertebral height and spinal range of motion at C4/5 segment at different time points was detected between postoperative results in the experimental group and preoperative results in the experimental group, normal control group. The intervertebral height at C4/5 segment was higher immediately, 4 and 8 weeks after surgery than preoperative result in the experimental group (P 0.05).术后4周时,手术组骨尚未与假体边缘接触;8周时骨与假体边缘间隙缩小,假体边缘有少量新生骨附着;12周时,假体表面有少量骨细胞存在,假体内部已有新生骨组织长入.表明金属橡胶角度人工椎间盘植入椎间隙后短期可维持椎间隙高度和活动度,与椎体结合牢固.

  12. Modeling and Control of the Springback Effect in the Bottom Sheet Metal Part One-Stage Drawing Process

    Directory of Open Access Journals (Sweden)

    A. S. Chumadin

    2014-01-01

    Full Text Available The main objective of this study is to reduce a manufacturing complexity of bottom sheet metal parts by improving the accuracy of parts produced. This study is aimed at using the finite element analysis to prove assumptions that there is a transition frontier between the processes of forming and drawing, and there are capabilities to control springback effect by moving this frontier positions.The process, the stress-strain state of which in the dome corresponds to the process of forming parts, and in the flange area to the drawing process, was considered to be a formingdrawing process.Based on previous studies, techniques to reduce a springback have been proposed which enable us to use three calculation schemes for the process simulation:The frontier transition position control between the processes of forming and drawing by changing the contact pressure on the flange by varying the frictions coefficients on the die and binder surfaces;Springback manage through the additional tensile forces in the flange area of the blank;Springback manage through the technological insert at the first process stage.For ease of comparison with previous research results the same geometric parameters and material properties of the items are used in the simulation.The springback analysis used a finite element method in the AutoFormTM incremental module with automatically mashed and standard tolerance computation properties. The blank, binder, punch, and die were then imported to the module by CATIATM interface in .iges format.The calculation has shown that the optimal value for the least thinning and springback parts are available for the second scheme whereby ring punch makes additional tension in the flange area (from 1.09 to 0.35 mm with thinning from 0.80 to 0.73 mm. The use of flange retention of sheet blank at the expense of variable frictional forces showed the springback value reduction by 4 times (from 1.09 to 0.27 mm. However thinning was 16% (from 0.80 to

  13. Double emulsions as fat replacers

    NARCIS (Netherlands)

    Oppermann, Anika

    2017-01-01

    The use of double (w1/o/w2) emulsions, in which part of the oil is replaced by small water droplets, is a promising strategy to reduce oil content in food products. For successful applications, (1) significant levels of fat reduction (i.e. significant amounts of water inside the oil droplets) have

  14. Metal/metalloid content in plant parts and soils of Corylus spp. influenced by mining-metallurgical production of copper.

    Science.gov (United States)

    Radojevic, Ana A; Serbula, Snezana M; Kalinovic, Tanja S; Kalinovic, Jelena V; Steharnik, Mirjana M; Petrovic, Jelena V; Milosavljevic, Jelena S

    2017-04-01

    The town of Bor and its surroundings (Serbia) have been under environmental pollution for more than a century, due to exploitation of large copper deposits. Naturally present Corylus spp. were sampled in the surroundings of the mine and flotation tailings at 12 sites distributed in six zones with different pollution loads, under the assumption that all the zones were endangered except for the background. As, Cd, Co, Cr, Cu, Fe, Mn, Mo, Ni, Pb and Zn inputs from soil and the air were evaluated in plant parts, in terms of absorption, accumulation and indication abilities of Corylus spp. The obtained results showed that As and Cu were the most enriched elements in soil, and their concentration exceeded the limit and remediation values proposed by the regulation. Plant parts (root, branch, leaf and catkin) also showed enrichment of most studied elements in wide ranges. According to the enrichment factor for plant, metal/metalloid inputs, particularly in leaves, were from anthropogenic origin. Plant absorption which occurred at the soil-root interface was low, based on the bioaccumulation factor, which could be indicative of resistance mechanisms of root to abiotic stress induced by a high content of elements in soil substrate. The values of bioaccumulation coefficient suggested weak and intermediate absorption and exclusion abilities of Corylus spp. to the studied elements. Element concentrations differ in unwashed and washed leaves, as well as pollution loads in plant and soil samples from the background, traffic and the sites with clear mining-metallurgical influence. Therefore, Corylus spp. could be promising in biomonitoring studies.

  15. The biogeochemical cycles of trace metals in the oceans.

    Science.gov (United States)

    Morel, F M M; Price, N M

    2003-05-01

    Planktonic uptake of some essential metals results in extraordinarily low concentrations in surface seawater. To sequester or take up these micronutrients, various microorganisms apparently release strong complexing agents and catalyze redox reactions that modify the bioavailability of trace metals and promote their rapid cycling in the upper water column. In turn, the low availability of some metals controls the rate of photosynthesis in parts of the oceans and the transformation and uptake of major nutrients such as nitrogen. The extremely low concentrations of several essential metals are both the cause and the result of ultraefficient uptake systems in the plankton and of widespread replacement of metals by one another for various biochemical functions.

  16. Concentration of Antifouling Biocides and Metals in Sediment Core Samples in the Northern Part of Hiroshima Bay

    Directory of Open Access Journals (Sweden)

    Noritaka Tsunemasa

    2014-06-01

    Full Text Available Accumulation of Ot alternative antifoulants in sediment is the focus of this research. Much research had been done on surface sediment, but in this report, the accumulation in the sediment core was studied. The Ot alternative antifoulants, Diuron, Sea-Nine211, and Irgarol 1051, and the latter’s degradation product, M1, were investigated in five samples from the northern part of Hiroshima Bay. Ot compounds (tributyltin (TBT and triphenyltin (TPT were also investigated for comparison. In addition, metal (Pb, Cu, Zn, Fe and Mn levels and chronology were measured to better understand what happens after accumulation on the sea floor. It was discovered that Ot alternative antifoulant accumulation characteristics in sediment were like Ot compounds, with the concentration in the sediment core being much higher than surface sediment. The concentration in sediment seems to have been affected by the regulation of Ot compounds in 1990, due to the concentration of Ot alternative antifoulants and Ot compounds at the survey point in front of the dock, showing an increase from almost the same layer after the regulation.

  17. [Flow of molten metal in denture base in horizontal centrifugal casting procedure. (Part 1) Flow, inflow volume and casting time of molten metal passing through single aprue into disk type mold (author's transl)].

    Science.gov (United States)

    Okamura, H

    1976-01-01

    A pyrex glass plate was fitted at the bottom of casting ring, and disk type wax pattern (thickness. 0.43 mm) was put on the plate. Five types of sprueing were applied. Pure tin was casted using holizontal centrifugal casting machine. Flow of molten metal was filmed by the motor drive camera with the method of stroboscope. The results were summarized as follows. 1) When the sprue was attached at the center of the disk type mold vertically, moten metal flowed like a concentric circle at the early stage of casting. It was affected gradually by the direction of gravity and revolution, and it filled the mold from the lower part to the upper part. 2) When the sprue gate was attached to the side edge of the mold, and the sprue gate was placed to the forward and backward direction against the revolution direction, molten metal filled from lower part to the upper part. 3) When the sprue gate was placed against upper edge, molten metal flow was affected by the direction of gravity and revolution. When the sprue gate was placed against lower edge, molten metal filled quietry from the lower part to the upper part. 4) Inflow volume per unit time (inflow rate) was small at the early stage of casting. Inflow rate increased and became constant at the next stage. At the latter stage it became small again. 5) Inflow rate increased with the increase of area of sprue. 6) The time which was necessary to fill the volume of 1 cm (about 80% of the mold volume) became short with the increase of area of sprue. It was also influenced by the type of sprueing.

  18. Humeral head replacement in the treatment of 3,4 parts fracture of the proximal humerus in elderly%人工肱骨头置换治疗老年肱骨近端三、四部分骨折

    Institute of Scientific and Technical Information of China (English)

    季卫平; 李浩; 黄自强; 华以雄; 朱云龙

    2012-01-01

    Objective To explore the elderly proximal humerus 3,4 part fractures of the humeral head arthroplasty indications, techniques and postoperative rehabilitation to restore shoulder function. Methods 15 elderly cases of proximal humeral 3,4 parts fracture patients were performed humeral head replacement. Preoperative measuring health side of the greater tuberosity low to the top of the head of the humerus distance, intraoperative reset size nodules, as far as possible the reasonable control of the false body height and sloping, try to repair the damage rotator cuff, three phase planned postoperative rehabilitation treatment. Results 15 cases have been followed up, followed up for 9 ~77 months. 11 cases were completely not painful, 2 cases of joint line after a tenderness, and 1 case lift on shoulder movement, and 1 case with mild pain shoulder instability Neer score standard display, excellent in 7 patients, good in 6, and poor in 2. Conclusions For the old proximal humeral fractures serious 3 ,4 parts, especially the head shattered fracture patients, the humeral head replacement is expected to get a good curative effect of treatment. In familiar anatomical and shoulder function based on the characteristics of the operation indication, strictly grasp, follow the head of the humerus replacement process the key technology of method, should as far as possible reserves during the greater tuberosity and soft tissue belongs to, close to anatomical reattachment, repair rotator cuff injury. With planned postoperative rehabilitation training, quickly shoulder activities can be restored.%目的 探讨老年肱骨近端三、四部分骨折行人工肱骨头置换术的适应证、技术要点及术后康复治疗对肩关节功能恢复的影响.方法 对15例老年肱骨近端三、四部分骨折患者行人工肱骨头置换.术前测量健侧大结节最低点至肱骨头最高点的距离;术中尽量复位大小结节,合理控制假体高度及后倾角度,尽

  19. 21 CFR 888.3340 - Hip joint metal/composite semi-constrained cemented prosthesis.

    Science.gov (United States)

    2010-04-01

    ... cemented prosthesis. 888.3340 Section 888.3340 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF... Hip joint metal/composite semi-constrained cemented prosthesis. (a) Identification. A hip joint metal/composite semi-constrained cemented prosthesis is a two-part device intended to be implanted to replace...

  20. Renal replacement therapy in ICU

    Directory of Open Access Journals (Sweden)

    C Deepa

    2012-01-01

    Full Text Available Diagnosing and managing critically ill patients with renal dysfunction is a part of the daily routine of an intensivist. Acute kidney insufficiency substantially contributes to the morbidity and mortality of critically ill patients. Renal replacement therapy (RRT not only does play a significant role in the treatment of patients with renal failure, acute as well as chronic, but also has spread its domains to the treatment of many other disease conditions such as myaesthenia gravis, septic shock and acute on chronic liver failure. This article briefly outlines the role of renal replacement therapy in ICU.

  1. Modeling of the distribution of heavy metals and trace elements in argan forest soil and parts of argan tree.

    Science.gov (United States)

    Mohammed, Faez A E; Bchitou, Rahma; Boulmane, Mohamed; Bouhaouss, Ahmed; Guillaume, Dominique

    2013-01-01

    The transfer of heavy metals and trace elements from argan forest soil into the wood, leaves, almonds, and argan oil was studied. Analyzed metals were: chromium, cadmium, copper, zinc, lead, calcium, phosphorus, potassium, and magnesium. Correlations linking different behaviors of the studied heavy metals and trace elements observed by multidimensional analysis were attributed to partial-spatial variations. Whereas the RV-coefficient of wood, leaf, almond and oil groups was high, the soil group correlated poorly with the other groups.

  2. Comparison of Cobalt Chrome Molybdenum release after metal on metal replacement between THA and TKA%金属对金属全髋关节置换与全膝关节置换术后早期钴铬钼离子的释出

    Institute of Scientific and Technical Information of China (English)

    王晓永; 张卫国; 吕德成; 李洪敬

    2009-01-01

    Objective To explore and compare the level of Cobalt chromium and Molybdenum in the patients after metal on metal replacement between THA and TKA in 6 months after operation. Methods From May 2007 to March 2008, metal on metal replacement of 10 THA and 8 TKA were included in this study. Blood samples were collected before operation, 2 weeks, 6 weeks, 12 weeks and 24 weeks after opera-tion in each patient. The concentration of Chromium (Cr), Cobalt (Co) and Molybdenum (Mo) ions in the plasma were measured by Double-focusing Inductively Coupled Plasma Mass Spectrometry (ICP-MS). Re-sults 1) The level of Cobalt, Chromium ion after metal on metal hip and knee replacement were signifi-cantly higher than normal. They increased sharply 2 weeks after operation, and reached the peak 6 weeks af-ter operation, then decreased gradually to the level of 2 weeks when it was 12 weeks after operation, and af-ter that they decreased slowly until 24 weeks after operation. 2) The concentration of Cobalt, Chromium ion in hip replacement group was lower than that of in knee replacement group. 3) The concentration of Cobalt and Chromium ion in patients using forging products were lower than those using casting products. 4) No sig-nificant changes were found in the concentration of Molybdenum ion in 6 months follow-up in two groups. Conclusion The concentration of Cobalt, Chromium ion increases after metal on metal replacement in THA and TKA. The concentration of Cobalt, Chromium ion in hip replacement group was lower than that of knee replacement group in 6 months after operation.%目的 研究金属对金属伞髋关节置换与全膝关节置换术后早期患者体内钴、铬、钼离子的释出情况.方法 选择2007年5月至2008年3月实施的金属对会属全髋关节置换10例,全膝关节置换8例.假体选择采取随机原则.分别于术前和术后第2、6、12、24周采集静脉全血,应用双聚焦电感耦合等离子体质谱法测量钴、铬、钼离子在

  3. Shoulder Joint Replacement

    Science.gov (United States)

    ... Shoulder Replacement Options Shoulder replacement surgery is highly technical. It should be performed by a surgical team ... area and will meet a doctor from the anesthesia department. You, your anesthesiologist, and your surgeon will ...

  4. Partial knee replacement - slideshow

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/presentations/100225.htm Partial knee replacement - series—Normal anatomy To use the sharing ... A.M. Editorial team. Related MedlinePlus Health Topics Knee Replacement A.D.A.M., Inc. is accredited ...

  5. Reaction Mechanisms of Metals with Hydrogen Sulfide and Thiols in Model Wine. Part 2: Iron- and Copper-Catalyzed Oxidation.

    Science.gov (United States)

    Kreitman, Gal Y; Danilewicz, John C; Jeffery, David W; Elias, Ryan J

    2016-05-25

    Sulfidic off-odors arising during wine production are frequently removed by Cu(II) fining. In part 1 of this study ( 10.1021/acs.jafc.6b00641 ), the reaction of H2S and thiols with Cu(II) was examined; however, the interaction of iron and copper is also known to play an important synergistic role in mediating non-enzymatic wine oxidation. The interaction of these two metals in the oxidation of H2S and thiols (cysteine, 3-sulfanylhexan-1-ol, and 6-sulfanylhexan-1-ol) was therefore examined under wine-like conditions. H2S and thiols (300 μM) were reacted with Fe(III) (100 or 200 μM) alone and in combination with Cu(II) (25 or 50 μM), and concentrations of H2S and thiols, oxygen, and acetaldehyde were monitored over time. H2S and thiols were shown to be slowly oxidized in the presence of Fe(III) alone and were not bound to Fe(III) under model wine conditions. However, Cu(II) added to model wine containing Fe(III) was quickly reduced by H2S and thiols to form Cu(I) complexes, which then rapidly reduced Fe(III) to Fe(II). Oxidation of Fe(II) in the presence of oxygen regenerated Fe(III) and completed the iron redox cycle. In addition, sulfur-derived oxidation products were observed, and the formation of organic polysulfanes was demonstrated.

  6. Heavy-metal Balances, Part II. Management of cadmium, copper, lead, and zinc in European Agro-Ecosystems

    NARCIS (Netherlands)

    Moolenaar, S.W.

    2000-01-01

    The aim of sustainable heavy-metal management in agro-ecosystems is to ensure that the soil continues to fulfill its functions: in agricultural production, in environmental processes such as the cycling of elements, and as a habitat of numerous organisms. To understand and manage heavy-metal flows e

  7. Heavy metal distribution in Laportea peduncularis and growth soil from the eastern parts of KwaZulu-Natal, South Africa.

    Science.gov (United States)

    Mahlangeni, Nomfundo T; Moodley, Roshila; Jonnalagadda, Sreekantha B

    2016-02-01

    Laportea peduncularis is a medicinal plant consumed by the native communities in South Africa. Due to its oral consumption, its potential for harming the human health and the distribution of metals in the leaves of L. peduncularis as a function of soil characteristics were evaluated. Broadly, the concentrations of metals in the soil were in decreasing order of Fe > Ca > Mg > Mn > Zn > Cr > Cu > Ni > As > Co > Cd > Pb. Low-molecular-weight organic acid, calcium chloride, and ethylenediaminetetraacetic acid extraction methods were employed to assess for exchangeable forms of metals in the soil. Geoaccumulation indices and enrichment factors showed no contamination or enrichment for most of the heavy metals studied except for Cd, which showed moderate contamination and significant enrichment at Mona, KwaZulu-Natal. Principal component and cluster analyses revealed that As, Cd, Fe, and Ni in the soil came from the same source, whilst Cu, Pb, and Zn in the soil were from a common origin. Correlation analysis showed significantly positive correlation between heavy metals As, Cd, Fe, and Ni in the soil, as well as between Cu, Pb, and Zn, confirming the metals' common origin. Concentrations of metals in plants and soil were influenced by site, but the availability and uptake of the metals solely depended on the plant's inherent controls.

  8. SELF-REGULATION AND INTERNAL AND EXTERNAL PARAMETERS IN METAL BAND FRICTION PAIRS-SHOE BRAKES (PART 1

    Directory of Open Access Journals (Sweden)

    Volchenko N. A.

    2014-09-01

    Full Text Available We've illustrated self-regulation (based on the work function of the metal friction element and the regula-tion by quasiconstant unit loads on the contact patch of micropoints of metal-polymer friction pairs of band-block brake for the evaluation of process of their normal wear

  9. MHD Instability Analysis of Liquid Metal Free Surface Jet Flow in Non-Uniform Magnetic Fields (Part Ⅱ)

    Institute of Scientific and Technical Information of China (English)

    XUZenyu; KANGWeishan; PANChuanjie; DENHongyin; ZHANGYanxu

    2003-01-01

    In lost paper of magneto-hydrodynamic instability analysis of liquid metal free surface jet flow (Part Ⅰ), the magneto-hydrodynamic instability was analyzed for the jet flow in a transverse non-uniform magnetic field, BT. But, as all known, for the real conditions of liquid metal limiter-divertor plasma-facing components are in toroidal and poloidal fields. So, we try to analyze the magneto-hydrodynamic instability of the jet flow (hereby only for circular shape cross section jet flow) in the zone of non-uniform magnetic fields,

  10. DC and RF characterization of InGaAs replacement metal gate (RMG) nFETs on SiGe-OI FinFETs fabricated by 3D monolithic integration

    Science.gov (United States)

    Deshpande, V.; Djara, V.; O'Connor, E.; Hashemi, P.; Balakrishnan, K.; Caimi, D.; Sousa, M.; Czornomaz, L.; Fompeyrine, J.

    2017-02-01

    We report the first RF characterization of short-channel replacement metal gate (RMG) InGaAs-OI nFETs built in a 3D monolithic (3DM) CMOS process. This process features RMG InGaAs-OI nFET top layer and SiGe-OI fin pFET bottom layer. We demonstrate state-of-the-art device integration on both levels. The bottom layer SiGe-OI pFETs are fabricated with a Gate-First (GF) process with fins and featuring epitaxial raised source drain (RSD) as well as silicide contact layer. The top layer InGaAs nFETs are fabricated with a RMG process featuring a self-aligned epitaxial raised source drain (RSD). We show that the 3D monolithic integration scheme does not degrade the performance of the bottom SiGe-OI pFETs owing to an optimized thermal budget for the top InGaAs nFETs. From the RF characterizations performed (post-3D monolithic process) on multifinger-gate InGaAs-OI nFETs, we extract a cut-off frequency (Ft) of 16.4 GHz at a gate-length (Lg) of 120 nm. Measurements on various gate lengths shows increasing cut-off frequency with decreasing gate-length.

  11. Accumulation and translocation of metals in soil and different parts of French bean (Phaseolus vulgaris L.) amended with sewage sludge.

    Science.gov (United States)

    Kumar, Vinod; Chopra, A K

    2014-01-01

    A pot experiment was conducted to study the accumulation and translocation of metals in French bean (Phaseolus vulgaris L.). Plants were grown in soil amended with up to 100 % sewage sludge. Significant (p vulgaris was noted in the treatment with 40 % of sewage sludge. Metal concentrations were significantly (p vulgaris after sewage sludge amendment where Fe > Zn > Cd > Cu > Cr > Pb. The translocation for Fe and Zn was in the order of leaves > shoot > root > fruits, for Cd, shoot > root > leaves > fruits, for Cu and Pb shoot > leaves > root > fruits and for Cr root > shoot > leaves > fruits of P. vulgaris. All accumulated metal concentrations except Cd in the fruit were below the FAO/WHO standard limits. Thus, the amendment of agricultural soil by sewage sludge might be feasible. However, a regular monitoring of metal levels in agricultural products is recommended to prevent their accumulation in the food chain.

  12. Bioaccumulation and ecological risk assessment of heavy metals in the sediments and mullet Liza klunzingeri in the northern part of the Persian Gulf.

    Science.gov (United States)

    Bastami, Kazem Darvish; Afkhami, Majid; Mohammadizadeh, Maria; Ehsanpour, Maryam; Chambari, Shahrokh; Aghaei, Sina; Esmaeilzadeh, Marjan; Neyestani, Mahmoud Reza; Lagzaee, Farahnaz; Baniamam, Mehrnaz

    2015-05-15

    The concentrations of some heavy metals (Cu, Zn, Pb and Cd) were investigated in the sediments and in the mullet Liza klunzingeri from the northern part of the Persian Gulf. The levels of Cu, Zn and Pb in the sediment varied significantly among the sampling sites (P<0.05). Sediments from the northern part of the Persian Gulf had serious ecological risk when considering PER. The ranges of the average concentrations of Cu, Zn, Pb, and Cd in the tissue of L. klunzingeri were 10.00-16.66 mg/kg, 18.75-32.50 mg/kg, 3.25-14.16 mg/kg and 0.37-3.33 mg/kg, respectively. The health risk analysis of individual heavy metals in the fish tissue indicated dangerous levels of Pb and Cd for the general population at some sampling sites.

  13. From Powders to Dense Metal Parts: Characterization of a Commercial AlSiMg Alloy Processed through Direct Metal Laser Sintering

    OpenAIRE

    Eleonora Atzeni; Elisa Paola Ambrosio; Riccardo Canali; Manickavasagam Krishnan; Flaviana Calignano; Diego Manfredi

    2013-01-01

    In this paper, a characterization of an AlSiMg alloy processed by direct metal laser sintering (DMLS) is presented, from the analysis of the starting powders, in terms of size, morphology and chemical composition, through to the evaluation of mechanical and microstructural properties of specimens built along different orientations parallel and perpendicular to the powder deposition plane. With respect to a similar aluminum alloy as-fabricated, a higher yield strength of about 40% due to the v...

  14. Metal flux and dynamic speciation at (bio)interfaces. Part VI: The roles of simple, fulvic and aggregate complexes on computed metal flux in freshwater ligand mixtures; comparison of Pb, Zn and Ni at planar and microspherical interfaces

    Science.gov (United States)

    Zhang, Zeshi; Buffle, Jacques

    2009-03-01

    The computations of metal flux in aquatic systems, at consuming interfaces like microorganism surfaces are of major importance in ecotoxicology and dynamic risk assessment. In this paper, the flux of Zn(II) and Ni(II), at a planar consuming interface in a typical natural freshwater, are studied. The system includes (a) simple ligands (OH -, CO32-); (b) fulvics; (c) aggregates, as complexants, i.e., those which play the major roles in controlling the metal distribution and/or metal flux in aquatic media. The above two metals are chosen because they participate, respectively, to intermediate and very slow chemical reactions with complexing sites, and are thus complementary to Pb(II) and Cu(II) (two metals with very fast reactions) studied in Parts III-V of this series. The effects of the various physico-chemical factors, in particular, the diffusion layer thickness, the stability constants and complexing site distribution of fulvics and the size distribution of aggregates, are studied in details. The contribution to the flux, of each complex type, is computed. This paper also compares the dynamic behaviour of Pb(II), Zn(II) and Ni(II) as well as the labilities and flux contributions of their various complexes at planar and microspherical interfaces. This enables to make predictions on biouptake by microorganisms.

  15. Aeronautical Information System Replacement -

    Data.gov (United States)

    Department of Transportation — Aeronautical Information System Replacement is a web-enabled, automation means for the collection and distribution of Service B messages, weather information, flight...

  16. Analysis of Pressure Variations in a Low-Pressure Nickel-Hydrogen Battery– Part 2: Cells with Metal Hydride Storage

    Science.gov (United States)

    Purushothaman, B. K.; Wainright, J. S.

    2012-01-01

    A sub-atmospheric pressure nickel hydrogen (Ni-H2) battery with metal hydride for hydrogen storage is developed for implantable neuroprosthetic devices. Pressure variations during charge and discharge of the cell are analyzed at different states of charge and are found to follow the desorption curve of the pressure composition isotherm (PCI) of the metal hydride. The measured pressure agreed well with the calculated theoretical pressure based on the PCI and is used to predict the state of charge of the battery. Hydrogen equilibration with the metal hydride during charge/discharge cycling is fast when the pressure is in the range from 8 to 13 psia and slower in the range from 6 to 8 psia. The time constant for the slower hydrogen equilibration, 1.37h, is similar to the time constant for oxygen recombination and therefore pressure changes due to different mechanisms are difficult to estimate. The self-discharge rate of the cell with metal hydride is two times lower in comparison to the cell with gaseous hydrogen storage alone and is a result of the lower pressure in the cell when the metal hydride is used. PMID:22711974

  17. Heavy Metals Accumulation in Topsoils from the Wine-growing Regions Part 1. Factors which Control Retention

    Directory of Open Access Journals (Sweden)

    Marija Romić

    2004-03-01

    Full Text Available The problem of exposure of agricultural soils to different anthropogenic inputs of heavy metals has been investigated in soils from two wine-producing subregions in northwestern Croatia. The aim of this study was to explore :(i the main soil properties and topsoil accumulation of heavy metals in vineyards under long-term cultivation, and (ii the origin and the preferential feature of metal retention in vineyard topsoil using the multivariate statistical method. The investigated area was marked on regular square grid with 1-km spacing. Topsoil samples (0-10 cm were collected from each sampling point and analyzed for soil chemical properties, particle size distribution and heavy metal concentrations after aqua region digestion. All soil data were incorporate into the GIS base. Summary statistics of the data set were first calculated to evaluate the distributions, and afterward processed by means of R-mode factor analysis, applying the varimax-raw rotational technique. Anthropogenic input of metals in soils of the studied wine-growing regions mostly originates from agrochemicals, since the direct influence of the urban environment or industry is almost negligible. Accumulation of copper and zinc in topsoil, determined in this research, is the most common effect of continuing fertilization and protection against diseases and pests in vineyards.

  18. Analysis of Pressure Variations in a Low-Pressure Nickel-Hydrogen Battery- Part 2: Cells with Metal Hydride Storage.

    Science.gov (United States)

    Purushothaman, B K; Wainright, J S

    2012-05-15

    A sub-atmospheric pressure nickel hydrogen (Ni-H(2)) battery with metal hydride for hydrogen storage is developed for implantable neuroprosthetic devices. Pressure variations during charge and discharge of the cell are analyzed at different states of charge and are found to follow the desorption curve of the pressure composition isotherm (PCI) of the metal hydride. The measured pressure agreed well with the calculated theoretical pressure based on the PCI and is used to predict the state of charge of the battery. Hydrogen equilibration with the metal hydride during charge/discharge cycling is fast when the pressure is in the range from 8 to 13 psia and slower in the range from 6 to 8 psia. The time constant for the slower hydrogen equilibration, 1.37h, is similar to the time constant for oxygen recombination and therefore pressure changes due to different mechanisms are difficult to estimate. The self-discharge rate of the cell with metal hydride is two times lower in comparison to the cell with gaseous hydrogen storage alone and is a result of the lower pressure in the cell when the metal hydride is used.

  19. Energy Dissipation and Apparent Viscosity of Semi-solid Metal during Rheological Processes Part Ⅰ: Energy Dissipation

    Institute of Scientific and Technical Information of China (English)

    Wen LIU; Shuming XING; Peiwei BAO; Milan ZHANG; Liming XIAO

    2007-01-01

    The energy dissipation caused by the viscous force has great effects on the flow property of semi-solid metal during rheological processes such as slurry preparing, delivering and cavity filling. Experimental results in this paper indicate that the viscous friction between semi-solid metal and pipe wall, the collisions among the solid particles, and the liquid flow around particles are the three main types of energy dissipation. On the basis of the hydromechanics, the energy dissipation calculation model is built. It is demonstrated that the micro-structural parameters such as effective solid fraction, particle size and shape, and flow parameters such as the mean velocity, the fluctuant velocity of particles and the relative velocity between the fluid and solid phase, affect the energy dissipation of semi-solid metal.

  20. From Powders to Dense Metal Parts: Characterization of a Commercial AlSiMg Alloy Processed through Direct Metal Laser Sintering

    Directory of Open Access Journals (Sweden)

    Eleonora Atzeni

    2013-03-01

    Full Text Available In this paper, a characterization of an AlSiMg alloy processed by direct metal laser sintering (DMLS is presented, from the analysis of the starting powders, in terms of size, morphology and chemical composition, through to the evaluation of mechanical and microstructural properties of specimens built along different orientations parallel and perpendicular to the powder deposition plane. With respect to a similar aluminum alloy as-fabricated, a higher yield strength of about 40% due to the very fine microstructure, closely related to the mechanisms involved in this additive process is observed.

  1. Life time assessment and repair of dissimilar metal welds. Part 2; Livslaengdsbedoemning och reparation av blandsvetsskarvar. Etapp 2

    Energy Technology Data Exchange (ETDEWEB)

    Storesund, Jan; Weilin Zang; Vinter Dahl, Kristian; Borggreen, Kjeld; Hald, John

    2007-12-15

    Phase 1 of the project showed that the research on dissimilar metal welds mainly has focussed on those including austenitic stainless steels. In addition, it was found that damage in dissimilar metal welds in Swedish and Danish power plants were frequent. In the present project the common type of dissimilar welds in the Nordic countries were studied; those between heat resistant low alloy steels and martensitic 9-12 % Cr steels. Three trial welds with three different filler materials were fabricated. The parent metals were 2,25Cr1Mo and 12Cr1MoV (X20) steels. The filler materials were 5Cr1Mo, 12Cr1MoV and a Ni-base alloy. One half of each weld was post weld heat treated (PWHT) at 650 deg C and the other half at 750 deg C. Then, a number of heat treatments at 600-660 deg C/1000 h to simulate service exposure for 50,000 to 200,000 h at 540 deg were carried out on test samples from the welds. The samples were studied metallographically, including measurements of hardness profiles and carbon content profiles. Thermodynamical simulations and creep damage simulations of butt welds were performed with data of the trial weld as a starting point. The purpose of the study was to get a throughout understanding of the creep behaviour of dissimilar metal welds, how their groove and fabrication can be improved, how their life time can be prolonged and how dissimilar weld should be non-destructively tested with respect to creep damage. From the results the following results may be drawn: - Carburised and decarburised zones develop during the PWHT. The zones are small with a PWHT at 650 deg C and relatively large at 750 deg C. They appear as measurable zones in the microstructure. 5Cr weld metal gives smaller zones than 12Cr weld metal. With the Ni-base weld metal intermittent decarburised zones could be observed across the wall after PWHT at 750 deg C. - The thermodynamical simulations predicted carburised and decarburised zones with sizes in agreement with corresponding heat

  2. Radiation Source Replacement Workshop

    Energy Technology Data Exchange (ETDEWEB)

    Griffin, Jeffrey W.; Moran, Traci L.; Bond, Leonard J.

    2010-12-01

    This report summarizes a Radiation Source Replacement Workshop in Houston Texas on October 27-28, 2010, which provided a forum for industry and researchers to exchange information and to discuss the issues relating to replacement of AmBe, and potentially other isotope sources used in well logging.

  3. 77 FR 14499 - Floor-Standing, Metal-Top Ironing Tables and Certain Parts Thereof From the People's Republic of...

    Science.gov (United States)

    2012-03-12

    ... Comment 2: Financial Ratios Comment 3: Errors in Calculation of Indonesian Surrogate Values Comment 4... Administrative Review, 76 FR 55357 (September 7, 2011) (Preliminary Results). \\2\\ See Floor-Standing, Metal-Top... Final Results of Administrative Review, 77 FR 1455 (January 10, 2012). Based on our analysis of...

  4. INJECTION MOLDING AND STRUCTURAL ANALYSIS IN METAL TO PLASTIC CONVERSION OF BOLTED FLANGE JOINT BY CAE

    Directory of Open Access Journals (Sweden)

    Marian Blaško

    2014-12-01

    Full Text Available Many metal parts in various applications are being replaced by plastic parts. There are several reasons for that depending on actual application - minimize part cost, enhance corrosion resistance, integrating more components into one part etc. Most important steps of metal to plastic conversion are material selection and design of plastic part. Plastic part has to withstand the same load as metal part. To fulfill this requirement fiber reinforced engineering plastics are often used. Also it is convenient to substitute heavy wall sections with ribbed structure to increase load-carrying ability of part and decrease cycle time, eliminate voids, sink marks etc. Mechanical properties of such part could be highly affected by fiber orientation. Results of fiber orientation from injection molding filling analysis can be used in stress analysis for better prediction of part response to mechanical load. Such coupled analysis is performed here in this case study on bolted flange joint.

  5. Kinetic model of hot-metal desulfurization by deep injection of synthetic powder mixtures - Part II; Modelo cinetico da dessulfuracao do gusa na panela atraves de injecao de misturas sinteticas - parte II

    Energy Technology Data Exchange (ETDEWEB)

    Sesshadri, V. [Minas Gerais Univ., Belo Horizonte, MG (Brazil). Dept. de Metalurgia; Silva, C.A. da; Silva, I.A. da [Ouro Preto Univ., MG (Brazil). Dept. de Metalurgia

    1995-12-31

    The model developed in Part I of this study was used to analyze a series of industrial trials of hot metal hot desulfurization by deep injection of Ca O base synthetic mixtures, using N{sub 2} as carrier gas. The model allows the simulation of the industrial practice and, under the examined conditions it was observed that the major contribution for the process desulfurization come from the top slag. However, since the values range covered by some other parameters were not extensive enough to affect the desulfurization, further experiments are required to fully assess the the influence of these variables 28 refs., 10 figs., 7 tabs.

  6. 14 CFR 21.9 - Replacement and modification articles.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Replacement and modification articles. 21.9... CERTIFICATION PROCEDURES FOR PRODUCTS AND PARTS General § 21.9 Replacement and modification articles. (a) If a person knows, or should know, that a replacement or modification article is reasonably likely to...

  7. The removal of toxic metals from liquid effluents by ion exchange resins. Part lll:Copper(ll/Sulphate/Amberlite 200

    Directory of Open Access Journals (Sweden)

    Alguacil, F. J.

    2003-06-01

    Full Text Available Copper(II adsorption from aqueous sulphate media on Amberlite 200 was investigated. The influence of operating variables such as aqueous pH, temperature and copper concentration on the metal adsorption kinetics was measured. The copper{II uptake is best fitted to the film-diffusion controlled process. The resin has been used in minicolumns to investigate its performance under dynamics conditions. Copper(II desorption from the resin is accomplished using sulphuric acid solutions.

    Se estudia la adsorción de cobre(II, de disoluciones en medio sulfato, en la resina Amberlite 200. La cinética de adsorción del metal se ha estudiado en función de una serie de variables experimentales: pH de la fase acuosa, temperatura y concentración del metal en el medio acuoso. La adsorción de cobre(II se puede correlacionar como controlada por un proceso de difusión en capa límite. Se ha utilizado la resina en minicolumnas para estudiar su comportamiento bajo condiciones dinámicas. La desorción del cobre(II se lleva a cabo con disoluciones de ácido sulfúrico.

  8. Current practice in primary total hip replacement: results from the National Hip Replacement Outcome Project

    OpenAIRE

    Best, A. J.; Fender, D.; Harper, W. M.; McCaskie, A. W.; Oliver, K; Gregg, P J

    1999-01-01

    As part of the National Study of Primary Hip Replacement Outcome, 402 consultant orthopaedic surgeons from three regions were contacted by postal questionnaire which covered all aspects of total hip replacement (THR). There was a 70% response rate of which 71 did not perform hip surgery, a further 33 refused to take part, leaving 181 valid responses. Preoperative assessment clinics were used by 89% of surgeons, but anaesthetists and rehabilitation services were rarely involved at this stage. ...

  9. Hormone Replacement Therapy

    Science.gov (United States)

    ... before and during menopause, the levels of female hormones can go up and down. This can cause ... hot flashes and vaginal dryness. Some women take hormone replacement therapy (HRT), also called menopausal hormone therapy, ...

  10. Knee joint replacement - slideshow

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/presentations/100088.htm Knee joint replacement - series—Normal anatomy To use the ... to slide 4 out of 4 Overview The knee is a complex joint. It contains the distal ...

  11. Product Platform Replacements

    DEFF Research Database (Denmark)

    Sköld, Martin; Karlsson, Christer

    2012-01-01

    Purpose – It is argued in this article that too little is known about product platforms and how to deal with them from a manager's point of view. Specifically, little information exists regarding when old established platforms are replaced by new generations in R&D and production environments...... originality and value is achieved by focusing on product platform replacements believed to represent a growing management challenge....

  12. Estudio de Factibilidad de Técnicas Vibroacústicas en la Detección de Discontinuidades en Metales. (Parte I. // Vibroacoustical techniques in metals discontinuity detection (part I.

    Directory of Open Access Journals (Sweden)

    F. de la Torre. Silva

    1999-07-01

    Full Text Available En este trabajo se presenta un estudio de factibilidad para la detección de discontinuidades en metales a partir de la aplicación detécnicas de ensayo vibroacústicas mediante la excitación sinusoidal e impulsiva. El análisis simultáneo que puede ser realizado a laseñal de entrada y de salida de un elemento metálico, reportaría una descripción del sistema en cuanto a sus propiedades dinámicasfundamentales, como lo son el caso de la Función Respuesta de Frecuencias y la Respuesta Impulsiva. Además, el uso de la Funciónde Correlación Cruzada, permitiría cuantificar el tiempo de propagación de la señal entre la entrada y la salida, para variaciones dediscontinuidades. El empleo de un Instrumento Virtual, sería la herramienta para la realización del análisis de señales. Se plantea unmodelo físico matemático teórico a partir del empleo del Método de los Elementos Finitos, implementado por el software MSC/PAL,el cual permitirá corroborar los resultados brindados por el diseño experimental, así como, estudiar dinámicamente el sistema objetode análisis.Palabras claves: factibilidad, fractura, vibroacústica, diagnóstico.__________________________________________________________________AbstractIn this work is presented a feasibility study for the discontinuities detection in metals as of the application of trial techniques vibraacoustic through the excitement sinusoidal and impulsive. The simultaneous analysis that it can be accomplished to the entry sign andof exit of a metallic element, would report a description of the system concerning their/its fundamental dynamic properties, as are thecase of the function frequencies response and impulsive response. Furthermore, the use of the correlation function crusade, wouldpermit quantify the spread time of the sign between the entry and the exit, for discontinuity variations. The employment of a virtualinstrument, would be the tool for the accomplishment of the signs analysis

  13. Synthesis and antibacterial activity of cephradine metal complexes : part II complexes with cobalt, copper, zinc and cadmium.

    Science.gov (United States)

    Sultana, Najma; Arayne, M Saeed; Afzal, M

    2005-01-01

    Cephradine, the first generation cephalosporin, is active against a wide range of Gram-positive and Gram-negative bacteria including penicillinase-producing Staphylococci. Since the presence of complexing ligand may affect the bioavailability of a metal in the blood or tissues, therefore, in order to study the probable interaction of cephradine with essential and trace elements present in human body, cephradine has been reacted with cobalt, copper, zinc and cadmium metal halides in L:M ratio of 2:1 in methanol and the products recrystallized from suitable solvents to pure crystals of consistent melting points. Infrared and ultraviolet studies of these complexes were carried out and compared with ligand. Magnetic susceptibility studies of these complexes were also carried out showing their paramagnetic behavior. From the infra red studies and elemental analysis of the complexes, it has been shown that the drug molecule serves as a bidentate ligand coordinating through both its carboxylate at C-3 and beta-lactam nitrogen and the metal having a square planar or octahedral geometry. To evaluate the changes in microbiological activity of cephradine after complexation, antibacterial studies were carried out by observing the changes in MIC (minimum inhibitory concentration) of the complexes and compared with the parent drug by measuring the zone of inhibition of complexes and compared with the parent cephalosporin against both Gram-positive and Gram-negative organisms. For MIC observation, serial dilution method was employed and zone series were determined by disk diffusion method. Our investigations reveal that formation of complexes results in decrease in antibacterial activity of cephradine and MIC values are increased.

  14. Corrosion of metals and alloys - Corrosion and fouling in industrial cooling water systems - Part 1: Guidelines for conducting pilot-scale evaluation of corrosion and fouling control additives for open recirculating cooling water systems

    CERN Document Server

    International Organization for Standardization. Geneva

    2006-01-01

    Corrosion of metals and alloys - Corrosion and fouling in industrial cooling water systems - Part 1: Guidelines for conducting pilot-scale evaluation of corrosion and fouling control additives for open recirculating cooling water systems

  15. EXPERIMENTAL STUDY ON MACRO AND MICRO-STRUCTURE OF METALLIC PARTS BUILT BY LOW-POWER LASER CLADDING

    Institute of Scientific and Technical Information of China (English)

    Liu Jichang; Li Lijun

    2005-01-01

    A low-power CO2 laser is used to deposit Fe powder and mixture of Fe and carbon powder on substrates respectively, and the macro and micro-structure of the formed samples are investigated.It is demonstrated that most grains of these samples are equi-axed. This is derived from the high nucleation velocity in the shallow melt pool besides rapid solidification of the liquid-state alloy or metal. Bainitic structure,combination of pearlite and ferrite structure and ferrite structure are seen respectively in the samples involving various amounts of carbon owing to no martensitic transformation in these small samples.

  16. [Part-time employment for the elderly in the North Rhine-Westphalia metal and electronics industry].

    Science.gov (United States)

    Barkholdt, C; Frerichs, F; Sczesny, C; Stackelbeck, M

    2000-08-01

    A postal survey targeted at 1000 firms in the metal- and electronic working industry of Northrhine Westfalia was carried out by Sozialforschungsstelle Dortmund und Institute of gerontology to analyze the implementation of the collective agreement concerning partial retirement. As the results show, firms in Northrhine Westfalia are willing to accept the collective agreement and use partial retirement though there are still problems left to solve. Firms are further using partial retirement as an instrument of early retirement. Therefore partial retirement is created as a so-called "blocked model".

  17. Replacing magnets at the LHC

    CERN Multimedia

    LHC, LSI2, Point 4

    2013-01-01

    CERN engineers have been working through the night this week to move the final replacement dipole magnets into position on the Large Hadron Collider (LHC). Though there are several still to go, the teams expect to have completed the task by the end of this month. Dipole magnets bend the paths of particles as they travel around the circular accelerator. Of the LHC's 1232 dipoles – each 15 metres long and weighing 35 tonnes – 15 are being replaced as part of the long shutdown of CERN's accelerator complex. These 15 magnets suffered wear and tear during the LHC's first 4-year run. Three quadrupole-magnet assemblies – which help to focus particles into a tight beam – have also been replaced. Moving such heavy magnets requires specially adapted cranes and trailers both above and below ground. There are several access points on the LHC. Some, such as the 100-metre vertical access shaft down to the ALICE experiment, are equipped with lifts to allow technical personnel and visitors down to the caverns. Other ...

  18. Environmental Beneficiation of Machining Wastes-Part III: Effects of Metal Working Fluids on the Spontaneous Heating of Machining Swarf.

    Science.gov (United States)

    Kawatra, S Komar; Hess, Mathew J

    1999-05-01

    Machining swarf is a finely divided metal powder that is prone to spontaneous heating and, in some cases, spontaneous combustion. The fine particle size, large amount of particle surface area, and the presence of moisture all promote rapid oxidation. This hazard dramatically increases disposal costs for swarf and interferes with recycling efforts. A potential method for minimizing spontaneous heating and facilitating recycling of the swarf is to spray a fluid on the material that coats the particles and creates a barrier between the metal and oxygen. Surface coatings could be tested for their effects on the spontaneous heating potential of swarf by treating a sample of swarf with a fluid that would coat the particles, then monitoring its heating behavior. This paper describes the results of applying corrosion inhibitors and machining fluids to the swarf, and monitoring the spontaneous heating behavior using a testing method developed specifically for this purpose. The effects of different types of surfactants and the effects of surfactant concentration on the spontaneous heating of swarf are discussed.

  19. Energy Dissipation and Apparent Viscosity of Semi-solid Metal during Rheological Processes Part Ⅱ: Apparent Viscosity

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    This study investigated the rheological properties of semi-solid metal. An analytical model of apparent viscosity was built up based on analysis of energy dissipation during rheological processes such as slurry preparing,delivering and model filling. The rheological properties of SSM (semi-solid metal) slurry was described by an analytical model in terms of microstructural parameters, which consist of effective solid fraction, particle size and shape, and flow parameters such as mean velocity, fluctuant velocity and relative velocity between liquid and solid phase. The model was verified in the experiment of A356 alloys with a coaxial double-bucket rheometer. And the maximum relative error between the theoretical value and measured one is less than 10%.The results of experiment and theoretical calculation also indicate that the microstructural parameters and flow parameters are two major factors that affect the apparent viscosity of semi-solid alloys, and fluctuant velocity and relative velocity between liquid and solid phase are the key factors to distinguish between steady and transient rheological properties.

  20. Cysteine-grafted nonwoven geotextile: a new and efficient material for heavy metals sorption--part A.

    Science.gov (United States)

    Vandenbossche, M; Casetta, M; Jimenez, M; Bellayer, S; Traisnel, M

    2014-01-01

    Cysteine is an interesting biomolecule in the heavy metals trapping field, thanks to its amino, thiol and carboxylic groups. This amino acid is indeed present in some natural chelating agents: glutathione, phytochelatins and metallothioneins. However, cysteine has never been used in remediation processes. When immobilized on a polypropylene nonwoven (PP) geotextile, an innovative and eco-friendly material is obtained, with potential use in drainage and filtration of wastewaters and sediments. PP was first functionalized with acrylic acid using a low pressure cold plasma process to bring reactive carboxylic functions onto the surface (PP-g-AA). Cysteine was then covalently grafted on this modified PP. The cysteine grafting on PP-g-AA was optimized using response surface methodology, which allowed concluding that the best conditions of immersion without heating consist in: a solution containing 0.229 mol/L of cysteine for 28 h. The materials were characterized by Scanning Electron Microscopy, InfraRed Spectroscopy and X-ray Photoelectron Spectroscopy: evidence of covalent cysteine grafting was given. Preliminary sorption tests at 20 °C and pH = 4.5 with artificially polluted solutions give promising results for divalent heavy metal ions: 95 mg Cu (II) (CuSO4 solution), 104 mg Cu (II) and 135 mg Pb(II) (with NO3(-) counter-ion) per gram of PP are trapped.

  1. Transition metal complexes of neocryptolepine analogues. Part I: Synthesis, spectroscopic characterization, and invitro anticancer activity of copper(II) complexes

    Science.gov (United States)

    Emam, Sanaa Moustafa; El Sayed, Ibrahim El Tantawy; Nassar, Nagla

    2015-03-01

    New generation of copper(II) complexes with aminoalkylaminoneocryptolepine as bidentate ligands has been synthesized and it is characterized by elemental analyses, magnetic moment, spectra (IR, UV-Vis, 1H NMR and ESR) and thermal studies. The IR data suggest the coordination modes for ligands which behave as a bidentate with copper(II) ion. Based on the elemental analysis, magnetic studies, electronic and ESR data, binuclear square planar geometry was proposed for complexes 7a, 7b, square pyramidal for 9a, 9b and octahedral for 8a, 8b, 10a, 10b. The molar conductance in DMF solution indicates that all complexes are electrolyte except 7a and 7b. The ESR spectra of solid copper(II) complexes in powder form showed an axial symmetry with 2B1g as a ground state and hyperfine structure. The thermal stability and degradation of the ligands and their metal complexes were studied employing DTA and TG methods. The metal-free ligands and their copper(II) complexes were tested for their in vitro anticancer activity against human colon carcinoma (HT-29). The results showed that the synthesized copper(II) complexes exhibited higher anticancer activity than their free ligands. Of all the studied copper(II) complexes, the bromo-substituted complex 9b exhibited high anticancer activity at low micromolar inhibitory concentrations (IC50 = 0.58 μM), compared to the other complexes and the free ligands.

  2. Fe-Substitution for Ni in Misch Metal-Based Superlattice Hydrogen Absorbing Alloys—Part 1. Structural, Hydrogen Storage, and Electrochemical Properties

    Directory of Open Access Journals (Sweden)

    Kwo-Hsiung Young

    2016-11-01

    Full Text Available The effects of Fe partially replacing Ni in a misch metal-based superlattice hydrogen absorbing alloy (HAA were studied. Addition of Fe increases the lattice constants and abundance of the main Ce2Ni7 phase, decreases the NdNi3 phase abundance, and increases the CaCu5 phase when the Fe content is above 2.3 at%. For the gaseous phase hydrogen storage (H-storage, Fe incorporation does not change the storage capacity or equilibrium pressure, but it does decrease the change in both entropy and enthalpy. With regard to electrochemistry, >2.3 at% Fe decreases both the full and high-rate discharge capacities due to the deterioration in both bulk transport (caused by decreased secondary phase abundance and consequent lower synergetic effect and surface electrochemical reaction (caused by the lower volume of the surface metallic Ni inclusions. In a low-temperature environment (−40 °C, although Fe increases the reactive surface area, it also severely hinders the ability of the surface catalytic, leading to a net increase in surface charge-transfer resistance. Even though Fe increases the abundance of the beneficial Ce2Ni7 phase with a trade-off for the relatively unfavorable NdNi3 phase, it also deteriorates the electrochemical performance due to a less active surface. Therefore, further surface treatment methods that are able to increase the surface catalytic ability in Fe-containing superlattice alloys and potentially reveal the positive contributions that Fe provides structurally are worth investigating in the future.

  3. 40 CFR Appendix I to Part 266 - Tier I and Tier II Feed Rate and Emissions Screening Limits for Metals

    Science.gov (United States)

    2010-07-01

    ... PROTECTION AGENCY (CONTINUED) SOLID WASTES (CONTINUED) STANDARDS FOR THE MANAGEMENT OF SPECIFIC HAZARDOUS WASTES AND SPECIFIC TYPES OF HAZARDOUS WASTE MANAGEMENT FACILITIES Pt. 266, App. I Appendix I to Part 266... Complex Terrain Values for urban and rural areas Terrain adjusted eff. stack ht. (m) Antimony (g/hr...

  4. A multi-channel bioluminescent bacterial biosensor for the on-line detection of metals and toxicity. Part II: technical development and proof of concept of the biosensor

    Energy Technology Data Exchange (ETDEWEB)

    Charrier, Thomas; Thouand, Gerald [UMR CNRS 6144 GEPEA, CBAC, Nantes University, PRES UNAM, Campus de la Courtaisiere-IUT, La Roche-sur-Yon cedex (France); Chapeau, Cyrille [Biolumine, Biokar Diagnostic, Rue des Quarante Mines ZAC de Ther-Allonne, Beauvais Cedex (France); Bendria, Loubna; Daniel, Philippe [UMR CNRS 6087 LPEC, Universite du Maine, Av Olivier Messiaen, Le Mans cedex 9 (France); Picart, Pascal [UMR CNRS 6613 IAM-LAUM, Ecole Nationale des Ingenieurs du Mans, Universite du Maine, Le Mans Cedex 9 (France)

    2011-05-15

    This research study deals with the on-line detection of heavy metals and toxicity within the context of environmental pollution monitoring. It describes the construction and the proof of concept of a multi-channel bioluminescent bacterial biosensor in immobilized phase: Lumisens3. This new versatile device, designed for the non-stop analysis of water pollution, enables the insertion of any bioluminescent strains (inducible or constitutive), immobilized in a multi-well removable card. The technical design of Lumisens3 has benefited from both a classical and a robust approach and includes four main parts: (1) a dedicated removable card contains 64 wells, 3 mm in depth, arranged in eight grooves within which bacteria are immobilized, (2) this card is incubated on a Pelletier block with a CCD cooled camera on top for bioluminescence monitoring, (3) a fluidic network feeds the card with the sample to be analyzed and finally (4) a dedicated computer interface, BIOLUX 1.0, controls all the elements of the biosensor, allowing it to operate autonomously. The proof of concept of this biosensor was performed using a set of four bioluminescent bacteria (Escherichia coli DH1 pBzntlux, pBarslux, pBcoplux, and E. coli XL1 pBfiluxCDABE) in the on-line detection of CdCl{sub 2} 0.5 {mu}M and As{sub 2}O{sub 3} 5 {mu}M from an influent. When considering metals individually, the ''fingerprints'' from the biosensor were as expected. However, when metals were mixed together, cross reaction and synergistic effects were detected. This biosensor allowed us to demonstrate the simultaneous on-line cross detection of one or several heavy metals as well as the measurement of the overall toxicity of the sample. (orig.)

  5. Processing of copper converter slag for metal reclamation. Part I: Extraction and recovery of copper and cobalt.

    Science.gov (United States)

    Deng, Tong; Ling, Yunhan

    2007-10-01

    Clean processing of copper converter slag to reclaim cobalt and copper could be a challenge. An innovative and environmentally sound approach for recovering valuable metals from such a slag has been developed in the present study. Curing the slag with strong sulphuric acid, without re-smelting or roasting as practiced currently in the industry, render it accessible to leaching, and more than 95% of cobalt and up to 90% of copper was extracted together with iron by water leaching, leaving silica behind in a residue. The copper in the leach liquor was recovered by cementation with iron and the dissolved iron crystallized as ferrous sulphate monohydrate. The cobalt in the mother-liquor rich in iron was recovered by either cementation or sulphide precipitation. Operation variables in the new process were also investigated and optimized.

  6. High resolution CCD spectra of stars in globular clusters. Part 2: Metals and CNO in M71

    Science.gov (United States)

    Leep, E. M.; Oke, J. B.; Wallerstein, G.

    1986-01-01

    Palomar coude CCD spectra of resolution 0.3 and 0.6 has been used to redetermine abundances in five stars of the relatively metal rich globular cluster M71. The (Fe/H) value is restricted to the limits of -0.6 to -1.0. The largest source of uncertainty is a systematic difference in f-values between those derived via the Holweger-Muller (1974) solar model and the Bell et al. (1976) solar model. If we use absolute f-values measured by the Oxford group (Blackwell et al. 1982) we find Fe/H to lie in the range of -0.6 to -0.75, i.e., as given by using the Bell et al. solar model. The relative abundances of the light elements, i.e., Na through Ca and probably including Ti show an average excess relative to iron of 0.4 dex. The effect of this difference on metal indices derived from broad- and narrow- band photometry is discussed. For three stars we find O/H = -0.6 using absolute f-values. For CN an analysis of individual rotational lines of the 2-0 band of the red system yields lines in the (C/H,N/H) plane that are consistent with either an original C/Fe = N/Fe = 0 or a modest increase in N relative to C due to CN burning and mixing. A search for C-13N was not successful and an uncertain lower limit of C-12/C-13 near 10 was obtained.

  7. Possibilities of the Technology of Additive Production for Making Complex-Shape Parts and Depositing Functional Coatings from Metallic Powders

    Science.gov (United States)

    Grigor'ev, S. N.; Tarasova, T. V.

    2016-01-01

    The aspects of terminology, definitions and classification in the technology of additive production are considered. The principal possibility of fabrication of complex-shape parts from a refractory cobalt alloy by the method of selective laser melting and deposition of hard and wear-resistant coatings from Ti and SiC powders by coaxial laser surfacing is shown. The technological possibility of microlaser surfacing with lateral resolution about 100 μm in the production of parts from aluminum alloys is considered. The mechanisms of formation of structure in the studied alloys typical for selective laser melting, laser surfacing and microlaser surfacing are determined. The physical and mechanical properties of the alloys are investigated.

  8. Dissolved metals and associated constituents in abandoned coal-mine discharges, Pennsylvania, USA. Part 1: Constituent quantities and correlations

    Science.gov (United States)

    Cravotta, C.A.

    2008-01-01

    Complete hydrochemical data are rarely reported for coal-mine discharges (CMD). This report summarizes major and trace-element concentrations and loadings for CMD at 140 abandoned mines in the Anthracite and Bituminous Coalfields of Pennsylvania. Clean-sampling and low-level analytical methods were used in 1999 to collect data that could be useful to determine potential environmental effects, remediation strategies, and quantities of valuable constituents. A subset of 10 sites was resampled in 2003 to analyze both the CMD and associated ochreous precipitates; the hydrochemical data were similar in 2003 and 1999. In 1999, the flow at the 140 CMD sites ranged from 0.028 to 2210 L s-1, with a median of 18.4 L s-1. The pH ranged from 2.7 to 7.3; concentrations (range in mg/L) of dissolved (0.45-??m pore-size filter) SO4 (34-2000), Fe (0.046-512), Mn (0.019-74), and Al (0.007-108) varied widely. Predominant metalloid elements were Si (2.7-31.3 mg L-1), B ( C > P = N = Se) were not elevated in the CMD samples compared to average river water or seawater. Compared to seawater, the CMD samples also were poor in halogens (Cl > Br > I > F), alkalies (Na > K > Li > Rb > Cs), most alkaline earths (Ca > Mg > Sr), and most metalloids but were enriched by two to four orders of magnitude with Fe, Al, Mn, Co, Be, Sc, Y and the lanthanide rare-earth elements, and one order of magnitude with Ni and Zn. The ochre samples collected at a subset of 10 sites in 2003 were dominantly goethite with minor ferrihydrite or lepidocrocite. None of the samples for this subset contained schwertmannite or was Al rich, but most contained minor aluminosilicate detritus. Compared to concentrations in global average shale, the ochres were rich in Fe, Ag, As and Au, but were poor in most other metals and rare earths. The ochres were not enriched compared to commercial ore deposits mined for Au or other valuable metals. Although similar to commercial Fe ores in composition, the ochres are dispersed and

  9. Clinical application and therapeutic effectiveness of large diameter head metal-on-metal total hip replacement%金属对金属大直径股骨头全髋关节置换术的临床应用及近期疗效观察

    Institute of Scientific and Technical Information of China (English)

    刘二涛; 徐皓; 陈建梅; 姚晓东; 李金泉

    2013-01-01

    Objective To explore the short-term results of total hip replacement THR ) using large diameter heads( LDH )in metal-on-metal( MOM )articulation. Methods A consecutive series of 34 patients( 34 hips )who underwent THR using LDH in MOM articulation were studied. The results were e-valuated both clinically and radio graphically. Clinical outcomes were evaluated according to the Harris e-valuation score and the R0M( Range of motion ). Acetabular position, components migration and bone changes around the implant were measured radiographically. Results The average follow-up period of all 34 patients was 18. 7 months. There was no bright line around the prosthesis. No complications such as os-teolysis, prosthetic loosening, heterotopic ossification and prosthesis fracture occurred. The average Harris hip score at the last follow-up was significantly improved compared with the preoperative scores( 87. 82 points versus 35. 29 points ). The postoperative ROM of all patients improved remarkably. Conclusion The short-term results of LDH in MOM total hip replacement on hip osteoarthritis, aseptic femoral head necrosis, femur neck fracture and congenital hip hypoplasia are excellent. But the long-term results of THR using LDH in MOM articulation still need further investigation.%目的 总结金属对金属大直径股骨头全髋关节置换术(total hip replacement,THR)的近期疗效.方法 回顾性分析行金属对金属大直径股骨头THR患者34例34髋.临床评估以Harris评分及髋关节活动度为标准.影像学根据双髋关节正位片,观察髋臼、股骨假体的位置及周围骨质的改变.结果 34例患者平均随访18.7个月.术后均无假体周围透亮线产生,无骨溶解、假体松动、异位骨化及假体断裂等并发症.Harris评分由术前的20~48分,平均(35.29±8.59)分,提高至术后随访时的76~96分,平均(87.82±5.12)分.所有患者髋关节活动度术后显著提高.结论 采用金属对金属大直径股骨

  10. IrII(ethene): metal or carbon radical? Part II: oxygenation via iridium or direct oxygenation at ethene?

    Science.gov (United States)

    Hetterscheid, Dennis G H; Bens, Mariska; de Bruin, Bas

    2005-03-07

    Treatment of [(Me3tpa)IrII(ethene)]2+ (Me(3)tpa =N,N,N-tri(6-methyl-2-pyridylmethyl)amine)(1(2+)) with dioxygen in weakly coordinating solvents results in formation of [(Me3tpa)IrIII(ethene)(superoxo)]2+ (4a2+). In the presence of DMPO (DMPO = 5,5-dimethyl-2-pyrrolidine-1-oxide) DMPO is substituted for ethene, and subsequently oxidized to DMPOX by the superoxo fragment to give [(Me3tpa)IrIII(DMPOX)]2+ (7(2+); DMPOX = 5,5-dimethyl-2-pyrrolidone-1-oxide). In acetonitrile, in the absence of DMPO, oxygenation of 1(2+) to [(Me3tpa)IrIII(formylmethyl)(MeCN)]2+ (2(2+)) is observed. In the presence of DMPO the formation of 2(2+) and 7(2+) is competing. Oxygenation of 1(2+) to 2(2+) may proceed via 4a(2+), involving an insertion mechanism at the metal. However, a mechanism based on olefin ligand non-innocence seems a reasonable alternative. This involves formation of acetonitrile adduct [(Me3tpa)Ir(ethene)(MeCN)]2+ (3(2+)), which has a significant metalla-ethyl radical (IrIII-CH2CH2*) character, allowing attack of 3O2 directly at the ethene ligand. Both pathways are discussed on the basis of experimental observations and DFT geometry optimizations.

  11. The charge percolation mechanism and simulation of Ziegler–Natta polymerizations Part III. Oxidation states of transition metals

    Directory of Open Access Journals (Sweden)

    BRANKA PILIC

    2006-04-01

    Full Text Available The oxidation state of the transition metal (Mt active centre is the most disputable question in the polymerization of olefins by Ziegler–Natta (ZN and metallocene complexes. In this paper the importance and the changes of the Mt active centres are presented and discussed on the basis of a charge percolation mechanism (CPM of olefin polymerization. Mt atoms can exist in different oxidation states and can be easily transformed from one to another state during activation. In all cases, the Mt atoms are present in several oxidation states, i.e., Mt+(n-1, Mt+(n to Mt+(n+1, producing an irregular charge distribution over the support surface. There is a tendency to equalize the oxidation states by a charge transfer from Mt+(n–1 (donor toMt+(n+1 (acceptor. This cannot occur since the different oxidation states are highly separated on the support. However, monomer molecules are adsorbed on the support producing clusters with stacked p-bonds, making a p-bond bridge between a donor and an acceptor. Once a bridge is formed (percolation moment, charge transfer occurs. The donor and acceptor equalize their oxidation states simultaneously with the polymerization of the monomer. The polymer chain is desorbed from the support, freeing the surface for subsequent monomer adsorption. The whole process is repeated with the oxidation-reduction of other donor-acceptor ensembles.

  12. Robotic mitral valve replacement.

    Science.gov (United States)

    Senay, Sahin; Gullu, Ahmet Umit; Kocyigit, Muharrem; Degirmencioglu, Aleks; Karabulut, Hasan; Alhan, Cem

    2014-01-01

    Robotic surgical techniques allow surgeons to perform mitral valve surgery. This procedure has gained acceptance, particularly for mitral valve repair in degenerative mitral disease. However, mitral repair may not always be possible, especially in severely calcified mitral valve of rheumatic origin. This study demonstrates the basic concepts and technique of robotic mitral valve replacement for valve pathologies that are not suitable for repair.

  13. Replacing America's Job Bank

    Science.gov (United States)

    Vollman, Jim

    2009-01-01

    The Job Central National Labor Exchange (www.jobcentral.com) has become the effective replacement for America's Job Bank with state workforce agencies and, increasingly, with community colleges throughout the country. The American Association of Community Colleges (AACC) has formed a partnership with Job Central to promote its use throughout the…

  14. Replacing America's Job Bank

    Science.gov (United States)

    Vollman, Jim

    2009-01-01

    The Job Central National Labor Exchange (www.jobcentral.com) has become the effective replacement for America's Job Bank with state workforce agencies and, increasingly, with community colleges throughout the country. The American Association of Community Colleges (AACC) has formed a partnership with Job Central to promote its use throughout the…

  15. Reverse Design for Metal Plate Parts Based on Parameterization%基于参数化的钣金零件逆向设计

    Institute of Scientific and Technical Information of China (English)

    李阳; 成思源; 杨雪荣; 张湘伟

    2015-01-01

    The point cloud data of the metal plate parts were obtained by using the articulated arm scanner system. The point cloud data were imported into the reverse software. Through point cloud processing, polygon processing and parameterization design, NURBS surface of the parts was constructed. Finally, the surface model was modified in forward software to get an ideal surface, with relatively higher quality and more fitting its features and original design ideas. By experiments, it is verified that the design requirement of date revert to original parts can be met by using the parameterization technology, so as to improve design efficiency.%通过关节臂测量机对钣金零件模型进行扫描得到其点云数据,将点云数据导入逆向软件中,经过点处理、多边形处理、参数化设计得到钣金零件的NURBS曲面,最后再经过正向软件的修改得到相对质量较高、符合零件本身特性和设计思想的理想曲面。通过实例验证了采用参数化技术可以还原零件数据的设计需求,以提高设计效率。

  16. Effects of metal-inlay thickness in polyethylene cups with metal-on-metal bearings.

    NARCIS (Netherlands)

    Verdonschot, N.J.J.; Vena, P.; Stolk, J.; Huiskes, R.

    2002-01-01

    A way to prevent polyethylene wear in total hip replacements is to use metal-on-metal bearings. The cup design of these bearings may be a metal inlay in a polyethylene cup. However, these metal inlays are relatively thin and may deform on loading. The purpose of the current study was to determine wh

  17. QUALITY CONTROL FOR PART REPLACEMENT OF FIXED TUBE SHEET HEAT EXCHANGER%固定管板式换热器部分构件更换过程中的质量控制

    Institute of Scientific and Technical Information of China (English)

    杨健

    2013-01-01

    针对制氢装置中的固定管板式换热器需更换壳体和管束,该换热器位于框架中间的平台上,出现无法直接用吊车吊运的情况.文章阐述了换热器拆除、壳体移位、壳体吊运、换热器安装、换热器管程水压试验等方面的施工技术要求和质量保证措施.%For the fixed tube sheet heat exchangers located within platform structures, it is impossible to lift them directly by crane when the shells and the bundles of the heat exchangers need to be replaced. This paper expatiates on the construction technical requirements concerning working procedures and quality assurance measures in dismantlement of heat exchangers, replacement, hoisting and moving of shells,installation and hydrostatic test of the tube side of fixed tube sheet heat exchangers.

  18. The calculation method of the bending length of sheet metal parts%钣金零件折弯展开长度的计算方法

    Institute of Scientific and Technical Information of China (English)

    樊瑞峰; 韩涛

    2013-01-01

    Aiming at the problem of low efficiency, large error and high cost in bending of sheet metal parts production,through parameter setting with K factor,at the same time listing the bending coefficient table of bending compensation and bending duduction, the high consistency between production and design can be realized by 3D software.%针对传统的钣金件生产中折弯展开下料效率低、误差大、成本高的问题,通过设定K因子参数,对折弯补偿和折弯扣除等折弯展开方式列出折弯系数表,再利用三维软件即可实现生产与设计的高度一致性.

  19. 小型薄板类零件加工工艺研究%Study on Machining Process of Small-sized Sheet Metal Parts

    Institute of Scientific and Technical Information of China (English)

    许超; 赵华

    2015-01-01

    Small-sized sheet metal parts are widely used in industries, but there exists some shortcomings such as poor rigidity, low strength, clamping deformation, low machining efficiency. Taking a typical small-sized sheet metal part as an example, after analyzing the traditional process, some means of improvement is given in many aspects such as block selection, machining process, workpiece clamping and so on. After a period of application in workshop, the new machining process has obtained good results in many aspects such as reducing production time, reducing work intensity, improving the rate of qualification, which greatly reduces the overall costs of the workpieces.%小型薄板类零件是工业中经常使用的零件,但是其刚性差、强度低、装夹易变形、加工效率低下。针对车间某一典型小型薄板类零件,对传统工艺进行分析,对工艺进行改进,在毛坯选择、加工思路、工件装夹等多个方面都进行了创新。经过实践证明,该加工工艺在工时的降低、工人劳动强度的减小、合格率的提高等多个方面都取得了很好的效果,大大降低了工件的综合成本。

  20. Research on Application of Zinc-coated Steel Panel in Automotive Sheet Metal Parts%汽车钣金件镀锌板应用研究

    Institute of Scientific and Technical Information of China (English)

    郭青华; 陈静; 李立军

    2012-01-01

    在整车开发中,车身防锈对于整车品质和市场定位起着决定性的作用。通过对前期开发车型易锈蚀部位调查,需对车门、地板、机盖及加油口等各个组成部分进行防锈控制。文章主要针对汽车钣金件镀锌板应用进行阐述,分别从镀锌板的分类及应用、优缺点及选择确定原则3方面深入研究,并对车身易锈蚀部位进行系统分析和控制,延长钣金件使用寿命,提高整车品质。%Anti-rust of auto body plays a decisive role in automobile quality and market position in automobile development. Investigation on susceptible to rusting parts of dour, floor, hood and fuel tank cover in developed vehicles is needed to be antirust control. Aimed at the application of zinc-coated steel panel for auto sheet metal parts, from the classification and application, advantages and disadvantages, determining principle of zinc-coated steel panel is studied. Systematic analysis and control on easy to rust parts are proceeded. Service life of stamping parts is prolonged and automobile quality is improved.

  1. Metal-enhanced fluorescence of graphene oxide by palladium nanoparticles in the blue-green part of the spectrum

    Science.gov (United States)

    Omidvar, A.; RashidianVaziri, M. R.; Jaleh, B.; Partovi Shabestari, N.; Noroozi, M.

    2016-11-01

    Graphene oxide (GO) has a wide fluorescence bandwidth, which makes it a prospective candidate for numerous applications. For many of these applications, the fluorescence yield of GO should be further increased. The sp2-hybridized carbons in GO confine the π-electrons. Radiative recombination of electron-hole pairs in such sp2 clusters is the source of fluorescence in this material. Palladium nanoparticles are good catalysts for sp2 bond formations. We report on the preparation of GO, palladium nanoparticles and their nanocomposites in two different solvents. It is shown that palladium nanoparticles can considerably enhance the intrinsic fluorescence of GO in the blue-green part of the visible light spectrum. Fluorescence enhancement has been attributed to the catalytic role of palladium nanoparticles in increasing the number of sp2 bonds of GO with the molecules of the surrounding media. It is shown that palladium nanoparticles could be the nanoparticle of choice for fluorescence enhancement of GO because of their catalytic role in sp2 bond formation.

  2. Ulnar head replacement.

    Science.gov (United States)

    Herbert, Timothy J; van Schoonhoven, Joerg

    2007-03-01

    Recent years have seen an increasing awareness of the anatomical and biomechanical significance of the distal radioulnar joint (DRUJ). With this has come a more critical approach to surgical management of DRUJ disorders and a realization that all forms of "excision arthroplasty" can only restore forearm rotation at the expense of forearm stability. This, in turn, has led to renewed interest in prosthetic replacement of the ulnar head, a procedure that had previously fallen into disrepute because of material failures with early implants, in particular, the Swanson silicone ulnar head replacement. In response to these early failures, a new prosthesis was developed in the early 1990s, using materials designed to withstand the loads across the DRUJ associated with normal functional use of the upper limb. Released onto the market in 1995 (Herbert ulnar head prosthesis), clinical experience during the last 10 years has shown that this prosthesis is able to restore forearm function after ulnar head excision and that the materials (ceramic head and noncemented titanium stem), even with normal use of the limb, are showing no signs of failure in the medium to long term. As experience with the use of an ulnar head prosthesis grows, so does its acceptance as a viable and attractive alternative to more traditional operations, such as the Darrach and Sauve-Kapandji procedures. This article discusses the current indications and contraindications for ulnar head replacement and details the surgical procedure, rehabilitation, and likely outcomes.

  3. Evaluation and Visualization of Surface Defects — a Numerical and Experimental Study on Sheet-Metal Parts

    Science.gov (United States)

    Andersson, A.

    2005-08-01

    The ability to predict surface defects in outer panels is of vital importance in the automotive industry, especially for brands in the premium car segment. Today, measures to prevent these defects can not be taken until a test part has been manufactured, which requires a great deal of time and expense. The decision as to whether a certain surface is of acceptable quality or not is based on subjective evaluation. It is quite possible to detect a defect by measurement, but it is not possible to correlate measured defects and the subjective evaluation. If all results could be based on the same criteria, it would be possible to compare a surface by both FE simulations, experiments and subjective evaluation with the same result. In order to find a solution concerning the prediction of surface defects, a laboratory tool was manufactured and analysed both experimentally and numerically. The tool represents the area around a fuel filler lid and the aim was to recreate surface defects, so-called "teddy bear ears". A major problem with the evaluation of such defects is that the panels are evaluated manually and to a great extent subjectivity is involved in the classification and judgement of the defects. In this study the same computer software was used for the evaluation of both the experimental and the numerical results. In this software the surface defects were indicated by a change in the curvature of the panel. The results showed good agreement between numerical and experimental results. Furthermore, the evaluation software gave a good indication of the appearance of the surface defects compared to an analysis done in existing tools for surface quality measurements. Since the agreement between numerical and experimental results was good, this indicates that these tools can be used for an early verification of surface defects in outer panels.

  4. PGPR 微生物肥代替部分化肥对豌豆生长的影响%Effect of partly replacing chemical fertilizer by PGPR biofertilizer on pea growth

    Institute of Scientific and Technical Information of China (English)

    荣良燕; 姚拓; 冯今; 杜笑村; 李儒仁; 陈龙

    2014-01-01

    The plant growth promoting rhizobacteria (PGPR)biofertilizer made from 5 phosphorous solving strains and 1 rhizobia was used to test the effect on pea growth through replacing 20% to 30% of chemical fer-tilizer under field condition.The results showed that 5 phosphorous solving strains (LM4-3,LH12-3,Lx1 91, Jm92,LHS1 1 and GDB27)did not show antagonistic effect each other and could be used for biofertilizer.The biofertilizer could replace 80% of chemical fertilizer and the height and seed yield of pea were increased by 6.3%and 3.2%,and the cost was reduced by 220 to 358 yuan/ha.%对前期从植物根际分离的促生菌(PGPR)进一步测定,筛选出5株优良溶磷菌株和1株根瘤菌株,并利用其制成 PGPR 微生物肥,研究其替代20%~30%化肥对豌豆生长及产量的影响。结果表明:菌株 LM4-3、LH12-3、Lx191、Jm92、LHS11与 GDB27互不产生拮抗,可制成 PGPR 微生物肥,研制的 PGPR 微生物肥替代20%化肥可使豌豆株高增加6.3%,经济产量提高3.2%,减少可购买性投入220.00~358.00元/hm2。

  5. PHASE EQUILIBRIA INVESTIGATIONS OF BINARY, TERNARY, AND HIGHER ORDER SYSTEMS. PART 2. EFFECT OF RHENIUM AND ALUMINUM ADDITIONS ON THE METAL-RICH EQUILIBRIA IN THE TITANIUM-MOLYBDENIUM-CARBON AND TITANIUM-NIOBIUM-CARBON SYSTEMS

    Science.gov (United States)

    The solid state phase equilibria of the metal-rich regions of the Titanium-Molybdenum-Carbon and Titanium-Niobium-Carbon systems with up to 12 At...Rhenium and 10 At.% Aluminum additions, respectively, have been determined on hot pressed, heat treated, and in part arc melted alloys. The phase ... equilibria in the metal-rich regions, with these additions, is practically unchanged over that of the ternary Titanium-Molybdenum-Carbon and Titanium

  6. A comparative study on tribological behavior between metal and polymeric composites used to repair bronze made parts in dry reciprocating sliding tests

    Science.gov (United States)

    Iliuţă, V.; Rîpă, M.; Javorova, J.; Andrei, G.

    2017-02-01

    The paper presents the researches on tribological behaviour of two materials used for parts subjected to friction, under dry sliding conditions. The composite material is a product of the company Diamant Metallplastic GmbH, Germany and the manufacturer recommend it for repairing or reconditioning worn or damaged bronze made parts. The material belongs to Multimetall category, which is a highly resistant 2-component repair system. This polymer composite material was tribologically tested in dry friction reciprocating conditions, in ball-on-flat configuration, using the tribometer UMT-2 (Bruker, former CETR). The counterpiece was a steel ball. Typical test conditions were as follows: normal loads of 20, 30, 40 and 50 N, sliding distance of 100 m, stroke length of 5mm, average sliding speed of 3,5 mm/s, room temperature and relative humidity of 50-60%. After testing, wear tracks were examined by electronic microscopy (SEM), laser profilometry and the profilometric module of the tribometer CETR-UMT-2. The results of the composite material analysis were compared with the similar ones obtained under similar test conditions for the bronze (metal material).

  7. Two different techniques of manufacturing TMJ replacements - A technical report.

    Science.gov (United States)

    Kozakiewicz, Marcin; Wach, Tomasz; Szymor, Piotr; Zieliński, Rafał

    2017-09-01

    Presently, during the surgical treatment of the patients in maxillofacial surgery, one can use various medical implants. Moreover custom made implants are being used. Replacements may be fitted to the structure and shape of the human skull owing to CAD/CAM (custom aided design/manufacture) called customized implants. This study was aimed to report for the first time clinical material from which custom implants, using two different techniques, were manufactured to reconstruct the temporomandibular joint (TMJ). In this study, eleven patients with an average age of 54 years were included. All of the patients underwent TMJ reconstruction using direct metal laser sintering (DMLS) or computer numerical control milling (CNC) techniques for implant manufacture. Four of the eleven patients had a malignancy diagnosis, and seven had a benign diagnosis. Patients complained of hypomobility of the TMJ, facial asymmetry, pain and swelling of the preauricular region. Treatment included 7 CNC milled implants and 4 implants in DMLS. More metallic implant parts with a rough surface were associated with the DMLS technique. Post operational, uneventful healing was observed in all clinical cases during an average of 26.8 months of follow-up. Three months post-operation, facial nerve palsy, swallowing disturbances and pain were not observed. Infections, allergic reactions to materials and re-ankylosis were also not observed. Replacements received correct forms and functions owing to the CAM techniques. Post-operational maximal interincisal opening improved (p < 0.01) and was not significantly related to preoperational opening, age, sex, diagnosis or adjuvant radiotherapy. Considering both methods, the feature that differentiates the manufacture technique is the more subtractive surface finishing required for the DMLS implant than the CNC implant. Both techniques resulted the same clinical outcomes and can be used successfully in patients with neoplastic lesions and other TMJ disorders

  8. Groin pain after metal-on-metal hip resurfacing prosthesis

    Directory of Open Access Journals (Sweden)

    Daniel Hernández-Vaquero

    2014-08-01

    Full Text Available Total hip replacement continues to be a widely successful operation, but persistent groin pain following a metal-on-metal hip resurfacing remains a problem for some patients. The concern regarding the safety and efficacy of metal-on-metal total hip replacements has been rising. We present the case of a 47-year-old man with groin pain after metal-on-metal hip resurfacing. We observed high metal ion levels detected in blood analytical studies and a pseudotumor in magnetic resonance imaging. Our patient was treated with a revision surgery. The progressive elevation of blood and urine metal levels in the presence of periarticular cysts and/or groin pain is a complication of metal-on-metal hip arthroplasty and needs revision surgery.

  9. Aortic valve replacement

    DEFF Research Database (Denmark)

    Kapetanakis, Emmanouil I; Athanasiou, Thanos; Mestres, Carlos A

    2008-01-01

    BACKGROUND AND AIMS OF THE STUDY: Prompted by anecdotal evidence and observations by surgeons, an investigation was undertaken into the potential differences in implanted aortic valve prosthesis sizes, during aortic valve replacement (AVR) procedures, between northern and southern European...... countries. METHODS: A multi-institutional, non-randomized, retrospective analysis was conducted among 2,932 patients who underwent AVR surgery at seven tertiary cardiac surgery centers throughout Europe. Demographic and perioperative variables including valve size and type, body surface area (BSA) and early...

  10. Total ankle joint replacement.

    Science.gov (United States)

    2016-02-01

    Ankle arthritis results in a stiff and painful ankle and can be a major cause of disability. For people with end-stage ankle arthritis, arthrodesis (ankle fusion) is effective at reducing pain in the shorter term, but results in a fixed joint, and over time the loss of mobility places stress on other joints in the foot that may lead to arthritis, pain and dysfunction. Another option is to perform a total ankle joint replacement, with the aim of giving the patient a mobile and pain-free ankle. In this article we review the efficacy of this procedure, including how it compares to ankle arthrodesis, and consider the indications and complications.

  11. The Optimum Replacement of Weapon

    Institute of Scientific and Technical Information of China (English)

    ZHANG Xiao; ZHANG Jin-chun

    2002-01-01

    The theory of LCC (Life Cycle Cost) is applied in this paper. The relation between the economic life of weapon and the optimum replacement is analyzed. The method to define the optimum replacement time of weapon is discussed.

  12. Power Plant Replacement Study

    Energy Technology Data Exchange (ETDEWEB)

    Reed, Gary

    2010-09-30

    This report represents the final report for the Eastern Illinois University power plant replacement study. It contains all related documentation from consideration of possible solutions to the final recommended option. Included are the economic justifications associated with the chosen solution along with application for environmental permitting for the selected project for construction. This final report will summarize the results of execution of an EPC (energy performance contract) investment grade audit (IGA) which lead to an energy services agreement (ESA). The project includes scope of work to design and install energy conservation measures which are guaranteed by the contractor to be self‐funding over its twenty year contract duration. The cost recovery is derived from systems performance improvements leading to energy savings. The prime focus of this EPC effort is to provide a replacement solution for Eastern Illinois University’s aging and failing circa 1925 central steam production plant. Twenty‐three ECMs were considered viable whose net impact will provide sufficient savings to successfully support the overall project objectives.

  13. Total disc replacement.

    Science.gov (United States)

    Vital, J-M; Boissière, L

    2014-02-01

    Total disc replacement (TDR) (partial disc replacement will not be described) has been used in the lumbar spine since the 1980s, and more recently in the cervical spine. Although the biomechanical concepts are the same and both are inserted through an anterior approach, lumbar TDR is conventionally indicated for chronic low back pain, whereas cervical TDR is used for soft discal hernia resulting in cervicobrachial neuralgia. The insertion technique must be rigorous, with precise centering in the disc space, taking account of vascular anatomy, which is more complex in the lumbar region, particularly proximally to L5-S1. All of the numerous studies, including prospective randomized comparative trials, have demonstrated non-inferiority to fusion, or even short-term superiority regarding speed of improvement. The main implant-related complication is bridging heterotopic ossification with resulting loss of range of motion and increased rates of adjacent segment degeneration, although with an incidence lower than after arthrodesis. A sufficiently long follow-up, which has not yet been reached, will be necessary to establish definitively an advantage for TDR, particularly in the cervical spine. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  14. REPLACEMENT OF FRENCH CARDS

    CERN Multimedia

    HR/SOC

    2001-01-01

    The French Ministry of Foreign Affairs has informed the Organization that it is shortly to replace all diplomatic cards, special cards and employment permits ('attestations de fonctions') now held by members of the personnel and their families. Between 2 July and 31 December 2001, these cards are to be replaced by secure, computerized equivalents. The old cards may continue to be used until 31 December 2001. For the purposes of the handover, members of the personnel must go personally to the cards office (33/1-015), in order to fill in a 'fiche individuelle' form, taking the following documents for themselves and members of their families already in possession of a French card : A recent identity photograph in 4.5 cm x 3.5 cm format. The French card in their possession. An A4 photocopy of the same French card, certified by the cards office as being a true copy. Those members of the personnel whose cards (and/or cards belonging to members of their families) are shortly due to expire, or have recently done...

  15. REPLACEMENT OF FRENCH CARDS

    CERN Multimedia

    Human Resources Division; Cards.Service@cern.ch

    2001-01-01

    The French Ministry of Foreign Affairs is currently replacing all diplomatic cards, special cards and employment permits («attestations de fonctions») held by members of the personnel and their families. These cards are replaced by secure, computerized equivalents. The old cards may no longer be used after 31 December 2001. For the purposes of the handover, members of the personnel must go personally to the cards office (33/1-015) between 8h30 and 12h30, in order to fill in a «fiche individuelle» form, taking the following documents for themselves and members of their families already in possession of a French card : A recent identity photograph in 4.5 cm x 3.5 cm format, the French card in their possession, an A4 photocopy of the same French card, certified by the cards office as being a true copy. Those members of the personnel whose cards (and/or cards belonging to members of their families) are shortly due to expire, or have recently done so, are also requested...

  16. REPLACEMENT OF FRENCH CARDS

    CERN Multimedia

    Human Resources Division

    2001-01-01

    The French Ministry of Foreign Affairs has informed the Organization that it is shortly to replace all diplomatic cards, special cards and employment permits ('attestations de fonctions') now held by members of the personnel and their families. Between 2 July and 31 December 2001, these cards are to be replaced by secure, computerized equivalents. The old cards may continue to be used until 31 December 2001. For the purposes of the handover, members of the personnel are asked to go to the cards office (33/1-015), taking the following documents for themselves and members of their families already in possession of a French card : A recent identity photograph in 4.5 cm x 3.5 cm format, The French card in their possession, an A4 photocopy of the same French card, certified by the cards office as being a true copy. Those members of the personnel whose cards (and/or cards belonging to members of their families) are shortly due to expire, or have recently done so, are also requested to take these items to the c...

  17. REPLACEMENT OF FRENCH CARDS

    CERN Multimedia

    Human Resources Division

    2001-01-01

    The French Ministry of Foreign Affairs has informed the Organization that it is shortly to replace all diplomatic cards, special cards and employment permits ('attestations de fonctions') now held by members of the personnel and their families. Between 2 July and 31 December 2001, these cards are to be replaced by secure, computerized equivalents. A 'personnel office' stamped photocopy of the old cards may continue to be used until 31 December 2001. For the purposes of the handover, members of the personnel must go personally to the cards office (33/1-015), between 8:30 and 12:30, in order to fill a 'fiche individuelle' form (in black ink only), which has to be personally signed by themselves and another separately signed by members of their family, taking the following documents for themselves and members of their families already in possession of a French card : A recent identity photograph in 4.5 cm x 3.5 cm format (signed on the back) The French card in their possession an A4 photocopy of the same Fre...

  18. Power Plant Replacement Study

    Energy Technology Data Exchange (ETDEWEB)

    Reed, Gary

    2010-09-30

    This report represents the final report for the Eastern Illinois University power plant replacement study. It contains all related documentation from consideration of possible solutions to the final recommended option. Included are the economic justifications associated with the chosen solution along with application for environmental permitting for the selected project for construction. This final report will summarize the results of execution of an EPC (energy performance contract) investment grade audit (IGA) which lead to an energy services agreement (ESA). The project includes scope of work to design and install energy conservation measures which are guaranteed by the contractor to be self-funding over its twenty year contract duration. The cost recovery is derived from systems performance improvements leading to energy savings. The prime focus of this EPC effort is to provide a replacement solution for Eastern Illinois University's aging and failing circa 1925 central steam production plant. Twenty-three ECMs were considered viable whose net impact will provide sufficient savings to successfully support the overall project objectives.

  19. Faster Replacement Paths

    CERN Document Server

    Williams, Virginia Vassilevska

    2010-01-01

    The replacement paths problem for directed graphs is to find for given nodes s and t and every edge e on the shortest path between them, the shortest path between s and t which avoids e. For unweighted directed graphs on n vertices, the best known algorithm runtime was \\tilde{O}(n^{2.5}) by Roditty and Zwick. For graphs with integer weights in {-M,...,M}, Weimann and Yuster recently showed that one can use fast matrix multiplication and solve the problem in O(Mn^{2.584}) time, a runtime which would be O(Mn^{2.33}) if the exponent \\omega of matrix multiplication is 2. We improve both of these algorithms. Our new algorithm also relies on fast matrix multiplication and runs in O(M n^{\\omega} polylog(n)) time if \\omega>2 and O(n^{2+\\eps}) for any \\eps>0 if \\omega=2. Our result shows that, at least for small integer weights, the replacement paths problem in directed graphs may be easier than the related all pairs shortest paths problem in directed graphs, as the current best runtime for the latter is \\Omega(n^{2.5...

  20. Power Plant Replacement Study

    Energy Technology Data Exchange (ETDEWEB)

    Reed, Gary

    2010-09-30

    This report represents the final report for the Eastern Illinois University power plant replacement study. It contains all related documentation from consideration of possible solutions to the final recommended option. Included are the economic justifications associated with the chosen solution along with application for environmental permitting for the selected project for construction. This final report will summarize the results of execution of an EPC (energy performance contract) investment grade audit (IGA) which lead to an energy services agreement (ESA). The project includes scope of work to design and install energy conservation measures which are guaranteed by the contractor to be self-funding over its twenty year contract duration. The cost recovery is derived from systems performance improvements leading to energy savings. The prime focus of this EPC effort is to provide a replacement solution for Eastern Illinois University’s aging and failing circa 1925 central steam production plant. Twenty-three ECMs were considered viable whose net impact will provide sufficient savings to successfully support the overall project objectives.

  1. Urban chaos and replacement dynamics in nature and society

    Science.gov (United States)

    Chen, Yanguang

    2014-11-01

    Replacements resulting from competition are ubiquitous phenomena in both nature and society. The evolution of a self-organized system is always a physical process substituting one type of components for another type of components. A logistic model of replacement dynamics has been proposed in terms of technical innovation and urbanization, but it fails to arouse widespread attention in the academia. This paper is devoted to laying the foundations of general replacement principle by using analogy and induction. The empirical base of this study is urban replacement, including urbanization and urban growth. The sigmoid functions can be employed to model various processes of replacement. Many mathematical methods such as allometric scaling and head/tail breaks can be applied to analyzing the processes and patterns of replacement. Among varied sigmoid functions, the logistic function is the basic and the simplest model of replacement dynamics. A new finding is that replacement can be associated with chaos in a nonlinear system, e.g., urban chaos is just a part of replacement dynamics. The aim of developing replacement theory is at understanding complex interaction and conversion. This theory provides a new way of looking at urbanization, technological innovation and diffusion, Volterra-Lotka’s predator-prey interaction, man-land relation, and dynastic changes resulting from peasant uprising, and all that. Especially, the periodic oscillations and chaos of replacement dynamics can be used to explain and predict the catastrophic occurrences in the physical and human systems.

  2. Wire-based laser metal deposition for additive manufacturing of TiAl6V4: basic investigations of microstructure and mechanical properties from build up parts

    Science.gov (United States)

    Klocke, Fritz; Arntz, Kristian; Klingbeil, Nils; Schulz, Martin

    2017-02-01

    The wire-based laser metal deposition (LMD-W) is a new technology which enables to produce complex parts made of titanium for the aerospace and automotive industry. For establishing the LMD-W as a new production process it has to be proven that the properties are comparable or superior to conventional produced parts. The mechanical properties were investigated by analysis of microstructure and tensile test. Therefore, specimens were generated using a 4.5 kW diode laser cladding system integrated in a 5-Axis-machining center. The structural mechanical properties are mainly influence by crystal structure and thereby the thermal history of the work piece. Especially the high affinity to oxide, distortion and dual phase microstructure make titanium grade 5 (TiAl6V4) one of the most challenging material for additive manufacturing. By using a proper local multi-nozzle shielding gas concept the negative influence of oxide in the process could be eliminated. The distortion being marginal at a single bead, accumulated to a macroscopic effect on the work piece. The third critical point for additive processing of titanium, the bimodal microstructure, could not be cleared by the laser process alone. All metallurgical probes showed α-martensitic-structure. Therefore, a thermal treatment became a necessary production step in the additive production chain. After the thermal treatment the microstructure as well as the distortion was analyzed and compared with the status before. Although not all technical issues could be solved, the investigation show that LMD-W of titanium grade 5 is a promising alternative to other additive techniques as electronic beam melting or plasma deposition welding.

  3. Toleration, Synthesis or Replacement?

    DEFF Research Database (Denmark)

    Holtermann, Jakob v. H.; Madsen, Mikael Rask

    2016-01-01

    to have considerable problems keeping a clear focus on the key question: What are the implications of this empirical turn in terms of philosophy of legal science, of the social understanding of IL, and, not least, of the place of doctrinal scholarship after the alleged Wende? What is needed, we argue......, in order to answer is not yet another partisan suggestion, but rather an attempt at making intelligible both the oppositions and the possibilities of synthesis between normative and empirical approaches to law. Based on our assessment and rational reconstruction of current arguments and positions, we...... therefore outline a taxonomy consisting of the following three basic, ideal-types in terms of the epistemological understanding of the interface of law and empirical studies: toleration, synthesis and replacement. This tripartite model proves useful with a view to teasing out and better articulating...

  4. Arthroscopic Management of Complications Following Total Ankle Replacement.

    Science.gov (United States)

    Lui, Tun Hing; Roukis, Thomas S

    2015-10-01

    There is great potential of managing the complications of total ankle replacement arthroscopically and endoscopically, and these procedures can be summarized into 3 groups. Group 1 includes procedures of the ankle joint proper with close proximity to the articular components of the total ankle replacement. Group 2 includes procedures of the tibia and talus with close proximity to the nonarticular parts of the total ankle replacement. Group 3 includes procedures that are away from the total ankle replacement. However, these remain master arthroscopist procedures and should be performed by foot and ankle surgeons who perform them with regularity.

  5. Determination of inorganic compounds in drinking water on the basis of house water heater scale, part 1: Determination of heavy metals and uranium

    Directory of Open Access Journals (Sweden)

    Rajković Miloš B.

    2004-01-01

    Full Text Available The analysis of scale originated from drinking water on the house water heater, showed that scale is basically calcium carbonate that crystallizes hexagonally in the form of calcite. Scale taken as a sample from different spots in Belgrade – upper town of Zemun (sample 1 and Pančevo (sample 2 showed different configuration although it came from the same waterworks. That indicates either that the water flowing through waterworks pipes in different parts of the city is not the same or the waterworks net is not the same (age, maintaining, etc. All the elements which are dominant in drinking water (Ca, Mg, K, and Na, and which could be found in water by natural processes, are by their content far below the values regulated by law. The analysis also showed the presence of many metals: Ti, Pb, Zn, Cu Li, Sr, Cd, and Cr in the first sample, which are not found in the scale taken near Pančevo. The results obtained by calculating the mass concentration in drinking water on the basis of scale content, showed that both waters belonged to the category of low mineral waters. Contents of inorganic substances in these waters (117.85 mg/dm3 for sample 1 or 80.83 mg/dm3 for sample 2 are twice lower than the values predicted by the legislation. Gammaspectrometric analysis indicates the presence of radioactive elements – uranium and strontium which can influence human health.

  6. Caffeic acid inhibits the formation of 1-hydroxyethyl radical in the reaction mixture of rat liver microsomes with ethanol partly through its metal chelating activity.

    Science.gov (United States)

    Ikeda, Hideyuki; Kimura, Yuka; Masaki, Miho; Iwahashi, Hideo

    2011-05-01

    Effect of caffeic acid on the formation of 1-hydroxyethyl radicals via the microsomal ethanol-oxidizing system pathway was examined. The electron spin resonance spin trapping showed that 1-hydroxyethyl radicals form in the control reaction mixture which contained 0.17 M ethanol, 1 mg protein/ml rat river microsomes, 0.1 M α-(4-pyridyl-1-oxide)-N-tert-butylnitrone, 5 mM nicotinamide adenine dinucleotide phosphate and 30 mM phosphate buffer (pH 7.4). When the electron spin resonance spectra of the control reaction mixtures with caffeic acid were measured, caffeic acid inhibited the formation of 1-hydroxyethyl radicals in a concentration dependent manner. Gallic acid, dopamine, l-dopa, chlorogenic acid and catechin also inhibited the formation of 1-hydroxyethyl radicals. Above results indicated that the catechol moiety is essential to the inhibitory effect. Caffeic acid seems to chelate of iron ion at the catechol moiety. Indeed, the inhibitory effect by caffeic acid was greatly diminished in the presence of desferrioxamine, a potent iron chelator which removes iron ion in the Fe (III)-caffeic acid complex. Since Fe (III)-desferrioxamine complex is active for the 1-hydroxyethyl radicals formation, caffeic acid inhibits the formation of 1-hydroxyethyl radicals in the reaction mixture partly through its metal chelating activity.

  7. Microwave discharge electrodeless lamps (MDEL). Part IV. Novel self-ignition system incorporating metallic microwave condensing cones to activate MDELs in photochemical reactions.

    Science.gov (United States)

    Horikoshi, Satoshi; Tsuchida, Akihiro; Sakai, Hideki; Abe, Masahiko; Sato, Susumu; Serpone, Nick

    2009-11-01

    A metallic condensing cone that concentrates microwave radiation (equivalent to an optical lens) has been developed and used as part of a system to activate a microwave discharge electrodeless lamp (MDEL) in the oxidative treatment of wastewaters by aiding the novel self-ignition of the lamp on irradiation at low microwave power levels. This approach to self-ignition can potentially lead to considerable energy savings in such treatments. System performance was examined for the ignition power of microwaves of such MDEL devices in water, whose usefulness was assessed by investigating the photolytic transformation of aqueous solutions of representatives of three classes of contaminants: chlorinated phenols, herbicides and endocrine disruptors, specifically 4-chlorophenol (4-CP), 2,4-dichlorophenoxyacetic acid (2,4-D) and 4,4'-isopropylidenediphenol (bisphenol-A; BPA), respectively, taken as model wastewaters in air-equilibrated, in oxygen-saturated and in TiO2-containing aqueous media. The results are discussed in terms of the dynamics of the photo-induced degradation processes.

  8. 钢锹类金属制件成型加热炉的改进%Improvement of heating furnace for spade type metal parts thermoforming

    Institute of Scientific and Technical Information of China (English)

    陈立东; 付长智; 邓春岩; 李亚靖; 张亮

    2012-01-01

    In order to reduce energy consumption and improve heating quality of the furnace for spade type metal parts, an improved furnace was designed with natural gas combustion and roller transmission instead of coal gas and chain conveyor, respectively. The results show that the heating system design is suitable, the workpieee can be heated uniformly, most heat energy can be recycled efficiently with a waste gas recovery device, and the fuel consumption is only about 50% of the original.%为了提高钢锹类金属制件热成型炉的加热质量,减少能量消耗,将原有煤气加热成型炉改进为天然气加热,同时将挂接式输送链传送改造成辊底传送。结果表明,加热制度设计合理,对工件加热均匀,燃料消耗仅为原来50%左右,同时采用废烟气能量回收装置可将大部分废热充分利用。

  9. Clinical trial design principles and endpoint definitions for transcatheter mitral valve repair and replacement: part 1: clinical trial design principles: A consensus document from the mitral valve academic research consortium.

    Science.gov (United States)

    Stone, Gregg W; Vahanian, Alec S; Adams, David H; Abraham, William T; Borer, Jeffrey S; Bax, Jeroen J; Schofer, Joachim; Cutlip, Donald E; Krucoff, Mitchell W; Blackstone, Eugene H; Généreux, Philippe; Mack, Michael J; Siegel, Robert J; Grayburn, Paul A; Enriquez-Sarano, Maurice; Lancellotti, Patrizio; Filippatos, Gerasimos; Kappetein, Arie Pieter

    2015-08-01

    Mitral regurgitation (MR) is one of the most prevalent valve disorders and has numerous aetiologies, including primary (organic) MR, due to underlying degenerative/structural mitral valve (MV) pathology, and secondary (functional) MR, which is principally caused by global or regional left ventricular remodelling and/or severe left atrial dilation. Diagnosis and optimal management of MR requires integration of valve disease and heart failure specialists, MV cardiac surgeons, interventional cardiologists with expertise in structural heart disease, and imaging experts. The introduction of transcatheter MV therapies has highlighted the need for a consensus approach to pragmatic clinical trial design and uniform endpoint definitions to evaluate outcomes in patients with MR. The Mitral Valve Academic Research Consortium is a collaboration between leading academic research organizations and physician-scientists specializing in MV disease from the United States and Europe. Three in-person meetings were held in Virginia and New York during which 44 heart failure, valve, and imaging experts, MV surgeons and interventional cardiologists, clinical trial specialists and statisticians, and representatives from the U.S. Food and Drug Administration considered all aspects of MV pathophysiology, prognosis, and therapies, culminating in a 2-part document describing consensus recommendations for clinical trial design (Part 1) and endpoint definitions (Part 2) to guide evaluation of transcatheter and surgical therapies for MR. The adoption of these recommendations will afford robustness and consistency in the comparative effectiveness evaluation of new devices and approaches to treat MR. These principles may be useful for regulatory assessment of new transcatheter MV devices, as well as for monitoring local and regional outcomes to guide quality improvement initiatives.

  10. Clinical Trial Design Principles and Endpoint Definitions for Transcatheter Mitral Valve Repair and Replacement: Part 1: Clinical Trial Design Principles: A Consensus Document From the Mitral Valve Academic Research Consortium.

    Science.gov (United States)

    Stone, Gregg W; Vahanian, Alec S; Adams, David H; Abraham, William T; Borer, Jeffrey S; Bax, Jeroen J; Schofer, Joachim; Cutlip, Donald E; Krucoff, Mitchell W; Blackstone, Eugene H; Généreux, Philippe; Mack, Michael J; Siegel, Robert J; Grayburn, Paul A; Enriquez-Sarano, Maurice; Lancellotti, Patrizio; Filippatos, Gerasimos; Kappetein, Arie Pieter

    2015-07-21

    Mitral regurgitation (MR) is one of the most prevalent valve disorders and has numerous etiologies, including primary (organic) MR, due to underlying degenerative/structural mitral valve (MV) pathology, and secondary (functional) MR, which is principally caused by global or regional left ventricular remodeling and/or severe left atrial dilation. Diagnosis and optimal management of MR requires integration of valve disease and heart failure specialists, MV cardiac surgeons, interventional cardiologists with expertise in structural heart disease, and imaging experts. The introduction of transcatheter MV therapies has highlighted the need for a consensus approach to pragmatic clinical trial design and uniform endpoint definitions to evaluate outcomes in patients with MR. The Mitral Valve Academic Research Consortium is a collaboration between leading academic research organizations and physician-scientists specializing in MV disease from the United States and Europe. Three in-person meetings were held in Virginia and New York during which 44 heart failure, valve, and imaging experts, MV surgeons and interventional cardiologists, clinical trial specialists and statisticians, and representatives from the U.S. Food and Drug Administration considered all aspects of MV pathophysiology, prognosis, and therapies, culminating in a 2-part document describing consensus recommendations for clinical trial design (Part 1) and endpoint definitions (Part 2) to guide evaluation of transcatheter and surgical therapies for MR. The adoption of these recommendations will afford robustness and consistency in the comparative effectiveness evaluation of new devices and approaches to treat MR. These principles may be useful for regulatory assessment of new transcatheter MV devices, as well as for monitoring local and regional outcomes to guide quality improvement initiatives. Copyright © 2015 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

  11. Clinical Trial Design Principles and Endpoint Definitions for Transcatheter Mitral Valve Repair and Replacement: Part 2: Endpoint Definitions: A Consensus Document From the Mitral Valve Academic Research Consortium.

    Science.gov (United States)

    Stone, Gregg W; Adams, David H; Abraham, William T; Kappetein, Arie Pieter; Généreux, Philippe; Vranckx, Pascal; Mehran, Roxana; Kuck, Karl-Heinz; Leon, Martin B; Piazza, Nicolo; Head, Stuart J; Filippatos, Gerasimos; Vahanian, Alec S

    2015-07-21

    Mitral regurgitation (MR) is one of the most prevalent valve disorders and has numerous etiologies, including primary (organic) MR, due to underlying degenerative/structural mitral valve (MV) pathology, and secondary (functional) MR, which is principally caused by global or regional left ventricular remodeling and/or severe left atrial dilation. Diagnosis and optimal management of MR requires integration of valve disease and heart failure specialists, MV cardiac surgeons, interventional cardiologists with expertise in structural heart disease, and imaging experts. The introduction of transcatheter MV therapies has highlighted the need for a consensus approach to pragmatic clinical trial design and uniform endpoint definitions to evaluate outcomes in patients with MR. The Mitral Valve Academic Research Consortium is a collaboration between leading academic research organizations and physician-scientists specializing in MV disease from the United States and Europe. Three in-person meetings were held in Virginia and New York during which 44 heart failure, valve, and imaging experts, MV surgeons and interventional cardiologists, clinical trial specialists and statisticians, and representatives from the U.S. Food and Drug Administration considered all aspects of MV pathophysiology, prognosis, and therapies, culminating in a 2-part document describing consensus recommendations for clinical trial design (Part 1) and endpoint definitions (Part 2) to guide evaluation of transcatheter and surgical therapies for MR. The adoption of these recommendations will afford robustness and consistency in the comparative effectiveness evaluation of new devices and approaches to treat MR. These principles may be useful for regulatory assessment of new transcatheter MV devices, as well as for monitoring local and regional outcomes to guide quality improvement initiatives.

  12. 21 CFR 888.3410 - Hip joint metal/polymer or ceramic/polymer semiconstrained resurfacing cemented prosthesis.

    Science.gov (United States)

    2010-04-01

    ... semiconstrained resurfacing cemented prosthesis. 888.3410 Section 888.3410 Food and Drugs FOOD AND DRUG... prosthesis. (a) Identification. A hip joint metal/polymer or ceramic/polymer semi-constrained resurfacing cemented prosthesis is a two-part device intended to be implanted to replace the articulating surfaces...

  13. New Firm Performance and the Replacement of Founder-CEOs

    DEFF Research Database (Denmark)

    Chen, Jing; Thompson, Peter

    2015-01-01

    We study the causes and consequences of the replacement of founder-CEOs in a sample of 4,172 Danish start-ups. We propose that founder-CEO replacement is driven in part by mismatches between business quality and founder ability. Our framework suggests that replacements are more likely among the w...... considerably faster. Our empirical results are consistent with these proposed predictions. Copyright © 2015 Strategic Management Society....... the worst- and best-performing firms, with low (high)-ability founders replaced by manager with higher (lower) ability. Replacement is not unambiguously associated with better subsequent performance. Firms that replaced the founder were much more likely to fail, but the surviving firms among them grew...

  14. Strategies for Revision Total Ankle Replacement

    Directory of Open Access Journals (Sweden)

    Thomas S. Roukis, DPM, PhD, FACFAS

    2014-12-01

    Full Text Available As the frequency of primary total ankle replacement (TAR continues to build, revision will become more commonplace. At present there are no “standard principles” associated with revision TAR. What is clear is that the current approaches are technically complex, fraught with complications and no one approach represents the only answer. Exchange of TAR metallic components to the same system standard or dedicated revision components are viable options with limited occurrence of complications. Explantation and conversion to custom-design long stemmed components has limited availability. Explantation and conversion to another TAR system is high-risk and has strong potential for complications. The use of metal reinforced polymethylmethacrylate cement augmentation of failed TAR systems and tibio-talo-calcaneal arthrodesis should be reserved for very select situations where other options are not possible. There is a real need for long-term survivorship following revision TAR and future efforts ought to be directed in this area.

  15. Applications of Metal Additive Manufacturing in Veterinary Orthopedic Surgery

    Science.gov (United States)

    Harrysson, Ola L. A.; Marcellin-Little, Denis J.; Horn, Timothy J.

    2015-03-01

    Veterinary medicine has undergone a rapid increase in specialization over the last three decades. Veterinarians now routinely perform joint replacement, neurosurgery, limb-sparing surgery, interventional radiology, radiation therapy, and other complex medical procedures. Many procedures involve advanced imaging and surgical planning. Evidence-based medicine has also become part of the modus operandi of veterinary clinicians. Modeling and additive manufacturing can provide individualized or customized therapeutic solutions to support the management of companion animals with complex medical problems. The use of metal additive manufacturing is increasing in veterinary orthopedic surgery. This review describes and discusses current and potential applications of metal additive manufacturing in veterinary orthopedic surgery.

  16. Membrane filtration studies of aquatic humic substances and their metal species: a concise overview. Part 2. Evaluation of conditional stability constants by using ultrafiltration.

    Science.gov (United States)

    Nifant'eva, T I; Shkinev, V M; Spivakov, B Y; Burba, P

    1999-02-01

    The assessment of conditional stability constants of aquatic humic substance (HS) metal complexes is overviewed with special emphasis on the application of ultrafiltration methods. Fundamentals and limitations of stability functions in the case of macromolecular and polydisperse metal-HS species in aquatic environments are critically discussed. The review summarizes the advantages and application of ultrafiltration for metal-HS complexation studies, discusses the comparibility and reliability of stability constants. The potential of ultrafiltration procedures for characterizing the lability of metal-HS species is also stressed.

  17. Iron replacement therapy

    DEFF Research Database (Denmark)

    Nielsen, Ole Haagen; Coskun, Mehmet; Weiss, Günter

    2016-01-01

    PURPOSE OF REVIEW: Approximately, one-third of the world's population suffers from anemia, and at least half of these cases are because of iron deficiency. With the introduction of new intravenous iron preparations over the last decade, uncertainty has arisen when these compounds should be admini...... treatment, when to follow-up for relapse, which dosage and type of therapy should be recommended or not recommended, and if some patients should not be treated....... be administered and under which circumstances oral therapy is still an appropriate and effective treatment. RECENT FINDINGS: Numerous guidelines are available, but none go into detail about therapeutic start and end points or how iron-deficiency anemia should be best treated depending on the underlying cause...... of iron deficiency or in regard to concomitant underlying or additional diseases. SUMMARY: The study points to major issues to be considered in revisions of future guidelines for the true optimal iron replacement therapy, including how to assess the need for treatment, when to start and when to stop...

  18. Metal-on-metal hip joint tribology.

    Science.gov (United States)

    Dowson, D; Jin, Z M

    2006-02-01

    The basic tribological features of metal-on-metal total hip replacements have been reviewed to facilitate an understanding of the engineering science underpinning the renaissance of these hard-on-hard joints. Metal-on-polymer hip replacements operate in the boundary lubrication regime, thus leading to the design guidance to reduce the femoral head diameter as much as is feasible to minimize frictional torque and volumetric wear. This explains why the gold-standard implant of this form from the past half-century had a diameter of only 22.225 mm (7/8 in). Metal-on-metal implants can operate in the mild mixed lubrication regime in which much of the applied load is supported by elastohydrodynamic films. Correct tribological design leads to remarkably low steady state wear rates. Promotion of the most effective elastohydrodynamic films calls for the largest possible head diameters and the smallest clearances that can reasonably be adopted, consistent with fine surface finishes, good sphericity and minimal structural elastic deformation of the cup on its foundations. This guidance, which is opposite in form to that developed for metal-on-polymer joints, is equally valid for solid (monolithic) metallic heads on metallic femoral stems and surface replacement femoral shells. Laboratory measurements of friction and wear in metal-on-metal joints have confirmed their potential to achieve a very mild form of mixed lubrication. The key lies in the generation of effective elastohydrodynamic lubricating films of adequate thickness compared with the composite roughness of the head and cup. The calculation of the film thickness is by no means easy, but the full procedure is outlined and the use of an empirical formula that displays good agreement with calculations based upon the full numerical solutions is explained. The representation of the lambda ratio, lambda, embracing both film thickness and composite roughness, is described.

  19. Laboratory Experiments on the Electrochemical Remediation of the Environment. Part 9: Microscale Recovery of a Soil Metal Pollutant and Its Extractant

    Science.gov (United States)

    Ibanez, Jorge G.; Balderas-Hernandez, Patricia; Garcia-Pintor, Elizabeth; Barba-Gonzalez, Sandy Nohemi; Doria-Serrano, Ma. del Carmen; Hernaiz-Arce, Lorena; Diaz-Perez, Armando; Lozano-Cusi, Ana

    2011-01-01

    Many soils throughout the world are contaminated with metal salts of diverse toxicity. We have developed an experiment to demonstrate the removal of a metal from an insoluble surrogate soil pollutant, CuCO[subscript 3] multiplied by Cu(OH)[subscript 2], by complexation followed by the simultaneous electrochemical recovery of the ligand (i.e.,…

  20. Laboratory Experiments on the Electrochemical Remediation of the Environment. Part 9: Microscale Recovery of a Soil Metal Pollutant and Its Extractant

    Science.gov (United States)

    Ibanez, Jorge G.; Balderas-Hernandez, Patricia; Garcia-Pintor, Elizabeth; Barba-Gonzalez, Sandy Nohemi; Doria-Serrano, Ma. del Carmen; Hernaiz-Arce, Lorena; Diaz-Perez, Armando; Lozano-Cusi, Ana

    2011-01-01

    Many soils throughout the world are contaminated with metal salts of diverse toxicity. We have developed an experiment to demonstrate the removal of a metal from an insoluble surrogate soil pollutant, CuCO[subscript 3] multiplied by Cu(OH)[subscript 2], by complexation followed by the simultaneous electrochemical recovery of the ligand (i.e.,…

  1. A comparative assessment of heavy metal accumulation in soft parts and byssus of mussels from subarctic, temperate, subtropical and tropical marine environments

    NARCIS (Netherlands)

    Szefer, P.; Fowler, S.W.; Ikuta, K.; Paez Osuna, F.; Ali, A.A.; Kim, B-S.; Fernandes, H.M.; Belzunce, M.J.; Guterstam, B.; Kunzendorf, H.; Wolowicz, M.; Hummel, H.; Deslous-Paoli, M.

    2006-01-01

    Existing data on metal concentrations in mussels from subarctic, temperate, subtropical and tropical waters were analyzed using multivariate statistics in order to assess regional variations in metal contamination. Potential errors were reduced by only analyzing data from surveys that employed the

  2. A comparative assessment of heavy metal accumulation in soft parts and byssus of mussels from subarctic, temperate, subtropical and tropical marine environments

    NARCIS (Netherlands)

    Szefer, P.; Fowler, S.W.; Ikuta, K.; Paez Osuna, F.; Ali, A.A.; Kim, B-S.; Fernandes, H.M.; Belzunce, M.J.; Guterstam, B.; Kunzendorf, H.; Wolowicz, M.; Hummel, H.; Deslous-Paoli, M.

    2006-01-01

    Existing data on metal concentrations in mussels from subarctic, temperate, subtropical and tropical waters were analyzed using multivariate statistics in order to assess regional variations in metal contamination. Potential errors were reduced by only analyzing data from surveys that employed the s

  3. Revision Total Hip Replacement: A Case Report

    Directory of Open Access Journals (Sweden)

    Md Hafizur Rahman

    2013-07-01

    Full Text Available Total hip replacement is a reconstructive procedure that has improved the management of those diseases of the hip joint that have responded poorly to conventional medical therapy. Conventional, primary total hip replacement is a durable operation in the majority of patients. A hip replacement is a mechanical device with parts that are assembled before and during the operation. But the possible complications of total hip arthroplasty, and its clinical performance over time, is a challenging occasion to the surgeons, and such a challenge we faced with our presenting patient. A 68 year old lady with history of cemented bipolar hemiarthroplasty done in a tertiary care hospital, due to fracture neck of the left femur having the history of diabetes, chronic kidney disease, heart disease, anaemia, and mental disorders presented with loosened prosthesis, thinning of medial proximal cortex of the femur which had broken within few months after surgery. She complained of painful walking at left hip joint. There was also evidence of chronic infective and degenerative arthritis of acetabular component of the affected hip joint. Cemented revision total hip replacement surgery was performed with expert multidisciplinary involvement. On 2nd postoperative day the patient was allowed to walk on operated limb with the aid of walker. On 12th postoperative day all the stitches were removed and wound was found healthy.

  4. Recent Developments of Metal and Metal Oxide Nanocatalysts in Organic Synthesis.

    Science.gov (United States)

    Makawana, Jigar A; Sangani, Chetan B; Yao, Yong-Fang; Duan, Yong-Tao; Lv, Peng-Cheng; Zhu, Hai-Liang

    2016-01-01

    Recently, various nanomaterials have been used in many organic transformations as efficient catalysts. The development of new catalysts by nanoscale design has emerged as a fertile field for research and innovation. The ability of nanotechnology to enhance catalytic activity opens the potential to replace expensive catalysts with lower amounts of inexpensive nanocatalysts. Besides, development of efficient and environmentally friendly synthetic methodologies for the synthesis of compound libraries of medicinal scaffolds is an attractive area of research in both academic and pharmaceutical industry. According to above reports and needs, this review deals with applications of nanoparticles as catalysts in various organic syntheses. We detail the topic of organic transformations using nanoparticles: Metal Nanoparticles and Metal Oxide Nanoparticles. In the latter part, different Metal Oxide Nanoparticles, such as ZnO Nanoparticle, TiO2 Nanoparticle, and CuO Nanoparticle are discussed.

  5. Trace metal emissions from the Estonian oil shale fired power

    DEFF Research Database (Denmark)

    Aunela-Tapola, Leena A.; Frandsen, Flemming; Häsänen, Erkki K.

    1998-01-01

    Emission levels of selected trace metals from the Estonian oil shale fired power plant were studied. The plant is the largest single power plant in Estonia with an electricity production capacity of 1170 MWe (1995). Trace metals were sampled from the flue gases by a manual method incorporating...... a two-fraction particle sampling and subsequent absorption of the gaseous fraction. The analyses were principally performed with ICP-MS techniques. The trace metal contents of Estonian oil shale were found to be in the same order of magnitude as of coal on average. The high total particle concentrations...... in the flue gases of the studied oil shale plant contribute, however, to clearly higher total trace metal emission levels compared to modern coal fired power plants. Although the old electrostatic precipitators in the plant have been partly replaced by state-of-the-art electrostatic precipitators...

  6. Educating My Replacement

    Science.gov (United States)

    Tarter, Jill

    , in partnership with the dedicated teachers out there, I think I can help promote the critical thinking skills and scientific literacy of the next generation of voters. Hopefully, I can also help train my replacement to be a better scientist, capable of seizing all the opportunities generated by advances in technology and our improved understanding of the universe to craft search strategies with greater probability of success than those I have initiated.

  7. Base Metal Co-Fired Multilayer Piezoelectrics

    Directory of Open Access Journals (Sweden)

    Lisheng Gao

    2016-03-01

    Full Text Available Piezoelectrics have been widely used in different kinds of applications, from the automobile industry to consumer electronics. The novel multilayer piezoelectrics, which are inspired by multilayer ceramic capacitors, not only minimize the size of the functional parts, but also maximize energy efficiency. Development of multilayer piezoelectric devices is at a significant crossroads on the way to achieving low costs, high efficiency, and excellent reliability. Concerning the costs of manufacturing multilayer piezoelectrics, the trend is to replace the costly noble metal internal electrodes with base metal materials. This paper discusses the materials development of metal co-firing and the progress of integrating current base metal chemistries. There are some significant considerations in metal co-firing multilayer piezoelectrics: retaining stoichiometry with volatile Pb and alkaline elements in ceramics, the selection of appropriate sintering agents to lower the sintering temperature with minimum impact on piezoelectric performance, and designing effective binder formulation for low pO2 burnout to prevent oxidation of Ni and Cu base metal.

  8. [Ascending aorta replacement late after aortic valve replacement].

    Science.gov (United States)

    Hayashi, Yasunari; Ito, Toshiaki; Maekawa, Atsuo; Sawaki, Sadanari; Fujii, Genyo; Hoshino, Satoshi; Tokoro, Masayoshi; Yanagisawa, Junji

    2013-07-01

    Replacement of the asceding aorta is indicated in patients undergoing aortic valve replacement( AVR), if the diameter of the ascending aorta is greater than 5.0 cm. If the diameter of the asceding aorta is from 4.0 to 5.0 cm, it was arguable whether replacement of the ascending aorta should be performed. Nine patients who underwent reoperative ascending aorta replacement after AVR were reviewed retrospectively. Reoperation on the asending aorta replacement was performed 11.8±7.2 years (range 1y5m~23y3m) after AVR. Mean patient age was 69.9±6.3 (range 60~81). In 2 cases, reoperations were performed early year after AVR. Although ascending aorta was dilated at the 1st operation, replacement wasn't performed for the age and minimally invasive cardiac surgery (MICS). In 3 cases, reoperations were performed more than 10 years later. On these cases, ascending aorta aneurysm and dissection occurred with no pain and were pointed out by computed tomography(CT) or ultrasonic cardiogram(UCG). We think that patients with dilatation of the ascending aorta should undergo AVR and aorta replacement at the 1st operation regardness of age. It is important that patients who underwent AVR should undergo a regular checkup on the ascending aorta.

  9. Metalloproteins and metal sensing.

    Science.gov (United States)

    Waldron, Kevin J; Rutherford, Julian C; Ford, Dianne; Robinson, Nigel J

    2009-08-13

    Almost half of all enzymes must associate with a particular metal to function. An ambition is to understand why each metal-protein partnership arose and how it is maintained. Metal availability provides part of the explanation, and has changed over geological time and varies between habitats but is held within vital limits in cells. Such homeostasis needs metal sensors, and there is an ongoing search to discover the metal-sensing mechanisms. For metalloproteins to acquire the right metals, metal sensors must correctly distinguish between the inorganic elements.

  10. A comparative assessment of heavy metal accumulation in soft parts and byssus of mussels from subarctic, temperate, subtropical and tropical marine environments.

    Science.gov (United States)

    Szefer, P; Fowler, S W; Ikuta, K; Osuna, F Paez; Ali, A A; Kim, B-S; Fernandes, H M; Belzunce, M-J; Guterstam, B; Kunzendorf, H; Wołowicz, M; Hummel, H; Deslous-Paoli, M

    2006-01-01

    Existing data on metal concentrations in mussels from subarctic, temperate, subtropical and tropical waters were analyzed using multivariate statistics in order to assess regional variations in metal contamination. Potential errors were reduced by only analyzing data from surveys that employed the same protocols, analytical methodologies and analysts. Factor analysis demonstrated that mussels inhabiting extremely contaminated areas (e.g. from Japanese and Swedish metallurgy sources) could be separated from mussels from other contaminated areas, and that metals such as Cd, Pb, Cu and Zn could be used to identify heavily contaminated samples while Co, Fe, Cr and Ni concentrations were good markers for exposure to inputs from different industrial sources. Furthermore byssus, like soft tissue, selectively and sensitively reflects variations of certain metal concentrations in ambient waters and thus serves as a reliable biomonitor for these contaminants in a variety of coastal and estuarine areas.

  11. Nicotine replacement therapies: patient safety and persistence

    Directory of Open Access Journals (Sweden)

    Ferguson SG

    2011-06-01

    Full Text Available Stuart G Ferguson1,2, Saul Shiffman3,4, Joseph G Gitchell51School of Pharmacy, 2Menzies Research Institute Tasmania, University of Tasmania, Hobart, Australia; 3Pinney Associates, 4University of Pittsburgh, Pittsburgh, PA, USA; 5Pinney Associates, Bethesda, MD, USAAbstract: Nicotine replacement therapy (NRT has become a central part of the treatment of nicotine dependence. However, NRT’s potential efficacy is limited to some extent by patient adherence and persistence. Here we review the relationship between NRT compliance and adherence, and overall treatment outcome. We then examine the factors that likely impact on treatment compliance and persistence, with a special focus on users’ perceptions of treatment safety and efficacy as possible mediators. Potential clinical strategies for improving suboptimal medication use are also discussed.Keywords: nicotine replacement therapy, compliance, safety

  12. Rare earth oxide reinforced Al{sub 2}O{sub 3}-TiO{sub 2} ceramics for inert coating of metallic parts for petroleum extraction

    Energy Technology Data Exchange (ETDEWEB)

    Yadava, Yoggendra Prasad; Rego, Sheila Alves Bezerra da Costa; Ferreira, Ricardo Artur Sanguinetti [Universidade Federal de Pernambuco (UFPE), Recife (Brazil)

    2012-07-01

    } reinforced Al{sub 2}O{sub 3}-20 wt% TiO{sub 2} ceramics for inert coating of metallic parts for petroleum extraction industry. (author)

  13. Research on the methods and standard of 3 d technology design for sheet metal parts%钣金件三维工艺设计方法及标准研究

    Institute of Scientific and Technical Information of China (English)

    程五四; 曾祥宇

    2015-01-01

    At present, sheet metal technology information expression by MBD( Model Based Definition) is the hot issue, but the standard is still in the blank .In view of the key technology of 3d technology design for sheet metal parts, it introduces the draft standard for electronic industry , expounds the main technical contents of the 3 d standard in detail .The application of standard can ensure the sheet metal technology information expression , and realize the effectively protect and the rapid development of 3d technology design for sheet metal parts .%根据钣金件三维工艺设计关键技术,总结提炼出3项电子行业标准草案,并详细阐述了标准的主要技术内容. 通过标准的应用,实现在三维模型上的电子装备钣金工艺信息的表达,确保基于模型定义的钣金工艺信息表达的规范性、通用性,有效保障和促进基于模型定义的三维钣金工艺设计技术的快速发展.

  14. Study on the role of catalase for uptake of metallic mercury Part 3 In vitro oxidation of metallic mercury by catalase and hydrogen peroxide generated by several oxidase system

    OpenAIRE

    劒持,堅志

    1984-01-01

    In vitro oxidation of metallic mercury by catalase and hydrogen peroxide generated by the glucose-glucose oxidase system, D-alanine-D-amino acid oxidase system and xanthine-xanthine oxidase-superoxide dismutase system was investigated. In vitro oxidation of metallic mercury by catalase and hydrogen peroxide generated by the reaction with glucose and glucose oxidase was observed in erythrocytes and crystalline beef liver catalase solution. The uptake depended on the concentration of glucose ox...

  15. Replacement of Asbestos Aboard Naval Aircraft.

    Science.gov (United States)

    1981-11-10

    Siding shingles and clapboard, including aoccesorlas Roofing shingles Asbets Textiles Yarn, cord, and thread Cloth Other asbestos textiles . including...all types Gakets (for sealing nonmoving parts) Asbestos, asbetos-metallic, and asbetos-ubber Packing (except leather , rubber, and metal) and abestos...c~ 0 oo N + -) ;-- (5"-00 0 . . SC C o U _ ’Do- - C. x 0 z I ok C L C; C 0 0S L ’-C -4 - - an t 0 - 0 _c - gc ~ .0 -o s.. - z 4- i r US v Q 6 U.~ cc

  16. Metal artifact reduction in cone beam computed tomography using forward projected reconstruction information

    Energy Technology Data Exchange (ETDEWEB)

    Meilinger, Manuel [Regensburg Univ. (Germany). CIML Group; Siemens Healthcare, Erlangen (Germany); Schmidgunst, Christian; Schuetz, Oliver [Siemens Healthcare, Erlangen (Germany); Lang, Elmar W. [Regensburg Univ. (Germany). CIML Group

    2011-07-01

    In this work we present a new method to reduce artifacts, produced by high-density objects, especially metal implants, in X-ray cone beam computed tomography (CBCT). These artifacts influence clinical diagnostics and treatments using CT data, if metal objects are located in the field of view (FOV). Our novel method reduces metal artifacts by virtually replacing the metal objects with tissue objects of the same shape. First, the considered objects must be segmented in the original 2D projection data as well as in a reconstructed 3D volume. The attenuation coefficients of the segmented voxels are replaced with adequate attenuation coefficients of tissue (or water), then the required parts of the volume are projected onto the segmented 2D pixels, to replace the original information. This corrected 2D data can then be reconstructed with reduced artifacts, i.e. all metal objects virtually vanished. After the reconstruction, the segmented 3D metal objects were re-inserted into the corrected 3D volume. Our method was developed for mobile C-arm CBCTs; as it is necessary that they are of low weight, the C-arm results in unpredictable distortion. This misalignment between the original 2D data and the forward projection of the reconstructed 3D volume must be adjusted before the correction of the segmented 2D pixels. We applied this technique to clinical data and will now present the results. (orig.)

  17. A comparative assessment of heavy metal accumulation in soft parts and byssus of mussels from subarctic, temperate, subtropical and tropical marine environments

    Energy Technology Data Exchange (ETDEWEB)

    Szefer, P. [Department of Food Sciences, Medical University of Gdansk, Al. Gen. J. Hallera 107, PL 80-416 Gdansk (Poland)]. E-mail: pszef@amg.gda.pl; Fowler, S.W. [IAEA Marine Environment Laboratory, 4 Quai Antoine 1er, MC-98000 (Monaco); Ikuta, K. [Laboratory of Aquatic Environment and Ecology, Department of Fisheries, Faculty of Agriculture, Miyazaki University, 889-21 Miyazaki (Japan); Osuna, F. Paez [Institute of Marine Sciences and Limnology, Mazatlan Station, National Autonomous University of Mexico, Mazatlan 82000, Sinaloa (Mexico); Ali, A.A. [Faculty of Science, Arts and Education, University of Aden, PO Box 6014, Khormaksar, Aden (Yemen); Kim, B.-S. [School of Earth and Environmental Science, Seoul National University, 56-1 Shillimdong, 151-742 (Korea, Republic of); Fernandes, H.M. [Instituto de Radioprotecao e Dosimetria, Cz. Postal 37 750 - CEP: 22642-970, Rio de Janeiro (Brazil); Belzunce, M.-J. [Instituto Tecnnologico Pesquero y Alimentario, Dpto de Oceanografia y Medio Ambiente Marino, Herrera Kaia, Portualdea z/g, 20110 Pasaia (Gipuzkoa) (Spain); Guterstam, B. [Stensund Ecological Center, 61991 Trosa, Sweden and Global Water Partnership Secretariat, Hantverkargatan 5, SE-112 21 Stockholm (Sweden); Kunzendorf, H. [Gamma Dating Center (GDC), Institute of Geography, University of Copenhagen, Oster Voldgage 10 DK-1350 Copenhagen K (Denmark); Wolowicz, M. [Laboratory of Estuarine Ecology, Institute of Oceanography, University of Gdansk, Al. Pilsudskiego 46, 81-378, Gdynia (Poland); Hummel, H. [Centre for Estuarine and Marine Ecology, Netherlands Institute of Ecology, Korringaweg 7, 4401 NT Yerseke (Netherlands); Deslous-Paoli, M. [IFREMER, Unite Ecologie Conchylicole, 1, rue Jean Vilar, 34200 Sete (France)

    2006-01-15

    Existing data on metal concentrations in mussels from subarctic, temperate, subtropical and tropical waters were analyzed using multivariate statistics in order to assess regional variations in metal contamination. Potential errors were reduced by only analyzing data from surveys that employed the same protocols, analytical methodologies and analysts. Factor analysis demonstrated that mussels inhabiting extremely contaminated areas (e.g. from Japanese and Swedish metallurgy sources) could be separated from mussels from other contaminated areas, and that metals such as Cd, Pb, Cu and Zn could be used to identify heavily contaminated samples while Co, Fe, Cr and Ni concentrations were good markers for exposure to inputs from different industrial sources. Furthermore byssus, like soft tissue, selectively and sensitively reflects variations of certain metal concentrations in ambient waters and thus serves as a reliable biomonitor for these contaminants in a variety of coastal and estuarine areas. - Byssus of mytilids, like soft tissues can be used as efficient biomonitor for heavy metals in the marine environment.

  18. Minimally invasive aortic valve replacement

    DEFF Research Database (Denmark)

    Foghsgaard, Signe; Schmidt, Thomas Andersen; Kjaergard, Henrik K

    2009-01-01

    In this descriptive prospective study, we evaluate the outcomes of surgery in 98 patients who were scheduled to undergo minimally invasive aortic valve replacement. These patients were compared with a group of 50 patients who underwent scheduled aortic valve replacement through a full sternotomy....... The 30-day mortality rate for the 98 patients was zero, although 14 of the 98 mini-sternotomies had to be converted to complete sternotomies intraoperatively due to technical problems. Such conversion doubled the operative time over that of the planned full sternotomies. In the group of patients whose...... is an excellent operation in selected patients, but its true advantages over conventional aortic valve replacement (other than a smaller scar) await evaluation by means of randomized clinical trial. The "extended mini-aortic valve replacement" operation, on the other hand, is a risky procedure that should...

  19. Study of the potential valorisation of heavy metal contaminated biomass via phytoremediation by fast pyrolysis: Part I. Influence of temperature, biomass species and solid heat carrier on the behaviour of heavy metals

    Energy Technology Data Exchange (ETDEWEB)

    C. Lievens; J. Yperman; J. Vangronsveld; R. Carleer [Hasselt University, Diepenbeek (Belgium). Laboratory of Applied Chemistry

    2008-08-15

    Presently, little or no information of implementing fast pyrolysis for looking into the potential valorisation of heavy metal contaminated biomass is available. Fast pyrolysis of heavy metal contaminated biomass (birch and sunflower), containing high amounts of Cd, Cu, Pb and Zn, resulting from phytoremediation, is investigated. The effect of the pyrolysis temperature (623, 673, 773 and 873 K) and the type of solid heat carrier (sand and fumed silica) on the distribution of the heavy metals in birch and sunflower pyrolysis fractions are studied. The goal of the set-up is 'concentrating' heavy metals in the ash/char fraction after thermal treatment, preventing them to be released in the condensable and/or volatile fractions. The knowledge of the behaviour of heavy metals affects directly future applications and valorisation of the pyrolysis products and thus contaminated biomass. They are indispensable for making and selecting the proper thermal conditions for their maximum recovery. In view of the future valorisation of these biomasses, the amounts of the pyrolysis fractions and the calorific values of the obtained liquid pyrolysis products, as a function of the pyrolysis temperature, are determined. 46 refs., 8 figs., 4 tabs.

  20. Accumulation of Metals in Soils, Groundwater and Edible Parts of Crops Grown Under Long-Term Irrigation with Sewage Mixed Industrial Effluents.

    Science.gov (United States)

    Yadav, R K; Minhas, P S; Lal, Khajanchi; Chaturvedi, R K; Yadav, Gajender; Verma, T P

    2015-08-01

    Farmers in developing countries irrigate crops using raw urban and industrial effluents with consequent risks from metal contamination. Therefore, soils, crops and groundwater from an effluent irrigation use site were assessed for Cd, Cr, Ni and Pb. Total and available contents of metals in soil followed the order Pb>Ni>Cr>Cd. Crops accumulated more Pb, followed by Cd, Ni and Cr. Pb exceeded the permissible limit with wastewater irrigation only, but Cd exceeded the limit even with combined irrigations of wastewater and groundwater. Among crops, sugar beet assimilated highest Cd (3.14 μg g(-1)) and Pb (6.42 μg g(-1)) concentrations. Legumes accumulated more metals than cereals. Long-term use of wastewater and its conjunctive use with groundwater led to toxic accumulations of Cd, Pb, Ni and Cr. Cd with higher availability and mobility indices and lower toxicity limit, posed the maximum risk of food-chain contamination.

  1. 21 CFR 888.3210 - Finger joint metal/metal constrained cemented prosthesis.

    Science.gov (United States)

    2010-04-01

    ... prosthesis. 888.3210 Section 888.3210 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... metal/metal constrained cemented prosthesis. (a) Identification. A finger joint metal/metal constrained cemented prosthesis is a device intended to be implanted to replace a metacarpophalangeal (finger)...

  2. 21 CFR 888.3200 - Finger joint metal/metal constrained uncemented prosthesis.

    Science.gov (United States)

    2010-04-01

    ... prosthesis. 888.3200 Section 888.3200 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... metal/metal constrained uncemented prosthesis. (a) Identification. A finger joint metal/metal constrained uncemented prosthesis is a device intended to be implanted to replace a metacarpophalangeal...

  3. Data on metal contents (As, Ag, Sr, Sn, Sb, and Mo in sediments and shells of Trachycardium lacunosum in the northern part of the Persian Gulf

    Directory of Open Access Journals (Sweden)

    Vahid Noroozi Karbasdehi

    2016-09-01

    Full Text Available In this data article, by using inductively coupled plasma optical spectrometry (ICP-OES1 Inductively Coupled Plasma Optical Spectrometry., we aimed to (1 determine the concentration levels of As, Ag, Sr, Sn, Sb, and Mo in the sediments and the shells of Trachycardium lacunosum simultaneously in two separated areas (unpolluted and polluted areas (2 comparison between the metal contents of sediments in the unpolluted and polluted areas as well as shells. Analysis of data showed that sediment as well as shell samples in polluted area contained significantly higher concentration levels of all measured metals compared with unpolluted area.

  4. Data on metal contents (As, Ag, Sr, Sn, Sb, and Mo) in sediments and shells of Trachycardium lacunosum in the northern part of the Persian Gulf.

    Science.gov (United States)

    Karbasdehi, Vahid Noroozi; Dobaradaran, Sina; Nabipour, Iraj; Arfaeinia, Hossein; Mirahmadi, Roghayeh; Keshtkar, Mozhgan

    2016-09-01

    In this data article, by using inductively coupled plasma optical spectrometry (ICP-OES), we aimed to (1) determine the concentration levels of As, Ag, Sr, Sn, Sb, and Mo in the sediments and the shells of Trachycardium lacunosum simultaneously in two separated areas (unpolluted and polluted areas) (2) comparison between the metal contents of sediments in the unpolluted and polluted areas as well as shells. Analysis of data showed that sediment as well as shell samples in polluted area contained significantly higher concentration levels of all measured metals compared with unpolluted area.

  5. Metal-Matrix/Hollow-Ceramic-Sphere Composites

    Science.gov (United States)

    Baker, Dean M.

    2011-01-01

    A family of metal/ceramic composite materials has been developed that are relatively inexpensive, lightweight alternatives to structural materials that are typified by beryllium, aluminum, and graphite/epoxy composites. These metal/ceramic composites were originally intended to replace beryllium (which is toxic and expensive) as a structural material for lightweight mirrors for aerospace applications. These materials also have potential utility in automotive and many other terrestrial applications in which there are requirements for lightweight materials that have high strengths and other tailorable properties as described below. The ceramic component of a material in this family consists of hollow ceramic spheres that have been formulated to be lightweight (0.5 g/cm3) and have high crush strength [40.80 ksi (.276.552 MPa)]. The hollow spheres are coated with a metal to enhance a specific performance . such as shielding against radiation (cosmic rays or x rays) or against electromagnetic interference at radio and lower frequencies, or a material to reduce the coefficient of thermal expansion (CTE) of the final composite material, and/or materials to mitigate any mismatch between the spheres and the matrix metal. Because of the high crush strength of the spheres, the initial composite workpiece can be forged or extruded into a high-strength part. The total time taken in processing from the raw ingredients to a finished part is typically 10 to 14 days depending on machining required.

  6. Iodine doped carbon nanotube cables exceeding specific electrical conductivity of metals

    Science.gov (United States)

    Zhao, Yao; Wei, Jinquan; Vajtai, Robert; Ajayan, Pulickel M.; Barrera, Enrique V.

    2011-09-01

    Creating highly electrically conducting cables from macroscopic aggregates of carbon nanotubes, to replace metallic wires, is still a dream. Here we report the fabrication of iodine-doped, double-walled nanotube cables having electrical resistivity reaching ~10-7 Ω.m. Due to the low density, their specific conductivity (conductivity/weight) is higher than copper and aluminum and is only just below that of the highest specific conductivity metal, sodium. The cables exhibit high current-carrying capacity of 104~105 A/cm2 and can be joined together into arbitrary length and diameter, without degradation of their electrical properties. The application of such nanotube cables is demonstrated by partly replacing metal wires in a household light bulb circuit. The conductivity variation as a function of temperature for the cables is five times smaller than that for copper. The high conductivity nanotube cables could find a range of applications, from low dimensional interconnects to transmission lines.

  7. Flow boiling test of GDP replacement coolants

    Energy Technology Data Exchange (ETDEWEB)

    Park, S.H. [comp.

    1995-08-01

    The tests were part of the CFC replacement program to identify and test alternate coolants to replace CFC-114 being used in the uranium enrichment plants at Paducah and Portsmouth. The coolants tested, C{sub 4}F{sub 10} and C{sub 4}F{sub 8}, were selected based on their compatibility with the uranium hexafluoride process gas and how well the boiling temperature and vapor pressure matched that of CFC-114. However, the heat of vaporization of both coolants is lower than that of CFC-114 requiring larger coolant mass flow than CFC-114 to remove the same amount of heat. The vapor pressure of these coolants is higher than CFC-114 within the cascade operational range, and each coolant can be used as a replacement coolant with some limitation at 3,300 hp operation. The results of the CFC-114/C{sub 4}F{sub 10} mixture tests show boiling heat transfer coefficient degraded to a minimum value with about 25% C{sub 4}F{sub 10} weight mixture in CFC-114 and the degree of degradation is about 20% from that of CFC-114 boiling heat transfer coefficient. This report consists of the final reports from Cudo Technologies, Ltd.

  8. The removal of toxic metals from liquid effluents by ion exchange resins. Part II: cadmium(II/ sulphate/Lewatit TP260

    Directory of Open Access Journals (Sweden)

    Alguacil, F. J.

    2002-10-01

    Full Text Available The adsorption of cadmium (II, from aqueous sulphate solutions, on Lewatit TP260 resin has been investigated in batch equilibrium experiments. The influence of pH and temperature on metal adsorption capacity have also been examined. The kinetic performance of the resin has been assesed and the results have been correlated by the pore diffusion model. The resin has been used in mini-columns to study its performance under dynamics conditions. The desorption of metal ion is achieved using sulphuric acid (0.25M and 0.5M.

    Se estudia la adsorción de cadmio(II, de disoluciones en medio sulfato, sobre la resina Lewatit TP260. La adsorción del metal se ha investigado en función del pH, la temperatura y el tiempo de contacto con la resina. Los estudios cinéticos permiten correlacionar el proceso de intercambio iónico con el modelo de difusión en poro. Se ha empleado el sistema en mini columnas para evaluar el comportamiento de la resina bajo condiciones dinámicas. La desorción del metal se lleva a cabo con disoluciones de ácido sulfúrico (0,25M y 0,5M.

  9. A multi-channel bioluminescent bacterial biosensor for the on-line detection of metals and toxicity. Part I: design and optimization of bioluminescent bacterial strains

    Energy Technology Data Exchange (ETDEWEB)

    Charrier, Thomas; Durand, Marie-Jose; Jouanneau, Sulivan; Thouand, Gerald [UMR CNRS 6144 GEPEA, CBAC, Nantes University, PRES UNAM, Campus de la Courtaisiere-IUT, La Roche-sur-Yon cedex (France); Dion, Michel [UMR CNRS 6204, Nantes University, PRES UNAM, Biotechnologie, Biocatalyse, Bioregulation, 2, Rue de la Houssiniere, BP 92208, Nantes cedex 3 (France); Pernetti, Mimma; Poncelet, Denis [ONIRIS-ENITIAA, UMR CNRS GEPEA, Rue de la Geraudiere, BP 82225, Nantes cedex 3 (France)

    2011-05-15

    This study describes the construction of inducible bioluminescent strains via genetic engineering along with their characterization and optimization in the detection of heavy metals. Firstly, a preliminary comparative study enabled us to select a suitable carbon substrate from pyruvate, glucose, citrate, diluted Luria-Bertani, and acetate. The latter carbon source provided the best induction ratios for comparison. Results showed that the three constructed inducible strains, Escherichia coli DH1 pBzntlux, pBarslux, and pBcoplux, were usable when conducting a bioassay after a 14-h overnight culture at 30 C. Utilizing these sensors gave a range of 12 detected heavy metals including several cross-detections. Detection limits for each metal were often close to and sometimes lower than the European standards for water pollution. Finally, in order to maintain sensitive bacteria within the future biosensor-measuring cell, the agarose immobilization matrix was compared to polyvinyl alcohol (PVA). Agarose was selected because the detection limits of the bioluminescent strains were not affected, in contrast to PVA. Specific detection and cross-detection ranges determined in this study will form the basis of a multiple metals detection system by the new multi-channel Lumisens3 biosensor. (orig.)

  10. Migration of Hazardous Substances Through Soil. Part 2. Determination of the Leachability of Metals from Five Industrial Wastes and Their Movement within Soil

    Science.gov (United States)

    1985-08-01

    or landfill leachate added as discussed below. Batchwise Serial Extraction Procedure-- Weight duplicate waste samples into Erylenmeyey flasks...waste extracts obtained from the batch serial extraction experiments. The samples were mixed for 24 hours, filtered and the metals remaining in the

  11. Metal release in a stainless steel Pulsed Electric Field (PEF) system Part I. Effect of different pulse shapes; theory and experimental method

    NARCIS (Netherlands)

    Roodenburg, B.; Morren, J.; Berg, H.E.; Haan, S.W.H.de

    2005-01-01

    Liquid pumpable food is mostly pasteurised by heat treatment. In the last decennia there is an increasing interest in so-called Pulsed Electric Field (PEF) treatment. During this treatment food is pumped between two metal electrodes and exposed to short high electric field pulses, typical 2-4 kV mm-

  12. From ligand to complexes. Part 2. Remarks on human immunodeficiency virus type 1 integrase inhibition by beta-diketo acid metal complexes.

    Science.gov (United States)

    Bacchi, Alessia; Biemmi, Mariano; Carcelli, Mauro; Carta, Fabrizio; Compari, Carlotta; Fisicaro, Emilia; Rogolino, Dominga; Sechi, Mario; Sippel, Martin; Sotriffer, Christoph A; Sanchez, Tino W; Neamati, Nouri

    2008-11-27

    Previously, we synthesized a series of beta-diketo acid metal complexes as novel HIV-1 integrase (IN) inhibitors (J. Med. Chem. 2006, 46, 4248-4260). Herein, a further extension of this study is reported. First, detailed docking studies were performed in order to investigate the mode of binding in the active site of the free ligands and of their metal complexes. Second, a series of potentiometric measurements were conducted for two diketo acids chosen as model ligands, with Mn(2+) and Ca(2+), in order to outline a speciation model. Third, we designed and synthesized a new set of complexes with different stoichiometries and tested them in an in vitro assay specific for IN. Finally, we obtained the first X-ray structure of a metal complex with HIV-1 IN inhibition activity. Analysis of these results supports the hypothesis that the diketo acids could act as complexes and form complexes with the metal ions on the active site of the enzyme.

  13. All-ceramic or metal-ceramic tooth-supported fixed dental prostheses (FDPs)? A systematic review of the survival and complication rates. Part I: Single crowns (SCs).

    Science.gov (United States)

    Sailer, Irena; Makarov, Nikolay Alexandrovich; Thoma, Daniel Stefan; Zwahlen, Marcel; Pjetursson, Bjarni Elvar

    2015-06-01

    To assess the 5-year survival of metal-ceramic and all-ceramic tooth-supported single crowns (SCs) and to describe the incidence of biological, technical and esthetic complications. Medline (PubMed), Embase, Cochrane Central Register of Controlled Trials (CENTRAL) searches (2006-2013) were performed for clinical studies focusing on tooth-supported fixed dental prostheses (FDPs) with a mean follow-up of at least 3 years. This was complimented by an additional hand search and the inclusion of 34 studies from a previous systematic review [1,2]. Survival and complication rates were analyzed using robust Poisson's regression models to obtain summary estimates of 5-year proportions. Sixty-seven studies reporting on 4663 metal-ceramic and 9434 all-ceramic SCs fulfilled the inclusion criteria. Seventeen studies reported on metal-ceramic crowns, and 54 studies reported on all-ceramic crowns. Meta-analysis of the included studies indicated an estimated survival rate of metal-ceramic SCs of 94.7% (95% CI: 94.1-96.9%) after 5 years. This was similar to the estimated 5-year survival rate of leucit or lithium-disilicate reinforced glass ceramic SCs (96.6%; 95% CI: 94.9-96.7%), of glass infiltrated alumina SCs (94.6%; 95% CI: 92.7-96%) and densely sintered alumina and zirconia SCs (96%; 95% CI: 93.8-97.5%; 92.1%; 95% CI: 82.8-95.6%). In contrast, the 5-year survival rates of feldspathic/silica-based ceramic crowns were lower (pceramic and zirconia crowns exhibited significantly lower survival rates in the posterior region (pceramic fractures than metal-ceramic SCs (pceramic SCs than for metal-ceramic SCs. Survival rates of most types of all-ceramic SCs were similar to those reported for metal-ceramic SCs, both in anterior and posterior regions. Weaker feldspathic/silica-based ceramics should be limited to applications in the anterior region. Zirconia-based SCs should not be considered as primary option due to their high incidence of technical problems. Copyright © 2015 Academy

  14. Evolution of tomosynthesis-shimadzu metal artifact reduction technology in assessment after artificial joint replacement%数字化体层融合-去金属伪影技术在人工关节置换术后评估的应用研究

    Institute of Scientific and Technical Information of China (English)

    吴雯丽; 田军; 张殿星; 孙博; 巩武贤

    2016-01-01

    Objective To investigate the application of tomosynthesis-shimadzu metal artifact reduction technology ( T-smart) in assessment after artificial joint replacement.Methods Thirty-nine patients with artificial joint replacement were selected in the study.After the DTS scan, the knee joints were reconstructed with FBP and T-smart methods, respectively.Then, the comparison between the two methods was done to analyze the value of T-smart technology.Results In the 39 patients, FBP:4 scores 15 scores (38.5%), 3 scores 22 scores, 2 scores 16 cases, 1 score 1 case, mean score 2.94; T-smart: 4 score 31 cases (79.5%), 3 scores 18 cases, 2 scores 5 cases,1 score 0 case, mean score 3.48.Conclusion T-smart technology can effective-ly remove the artifacts of artificial prosthesis, and clearly show the relationship between the prosthesis and surrounding bone.It can also overcome the difficulty of correctly evaluating the periprosthetic bone resulting from the organizations overlap of X-ray, MSCT metal artifacts and MRI metal distortion.This will be helpful for the early diagnosis of prosthetic loosening and metal worn particle disease.T-smart technology can be a major method to evaluate the prosthesis stability after prosthesis implantation.%目的:探讨数字化体层融合-去金属伪影技术在人工关节置换术后评估的应用价值。方法选取人工关节置换术后的39例患者,包括髋关节和膝关节,分别用FBP与T-smart两种方法进行重建,对比评价两种图像的质量,分析T-smart对评估人工关节置换术的价值。结果39例患者(包括髋和膝共54个关节)中,FBP图像4分15例,比率为38.5%;3分22例,2分为16例,1分1例,平均分为2.94;T-smart图像4分31例,比率为79.5%;3分18例,2分为5例,1分0例,平均分为3.48。结论 T-Smart技术能够有效地去除DTS图像上人工假体产生的伪影,清晰显示假体与周围骨质的关系;能够克服由于X线平片组

  15. Causes of toxicity to Hyalella azteca in a stormwater management facility receiving highway runoff and snowmelt. Part I: polycyclic aromatic hydrocarbons and metals.

    Science.gov (United States)

    Bartlett, A J; Rochfort, Q; Brown, L R; Marsalek, J

    2012-01-01

    The Terraview-Willowfield Stormwater Management Facility (TWSMF) receives inputs of multiple contaminants, including metals, polycyclic aromatic hydrocarbons (PAHs), road salt, and nutrients, via highway and residential runoff. Contaminant concentrations in runoff are seasonally dependent, and are typically high in early spring, coinciding with the snowmelt. In order to investigate the seasonal fluctuations of contaminant loading and related changes in toxicity to benthic invertebrates, overlying water and sediment samples were collected in the fall and spring, reflecting low and high contaminant loading, respectively, and four-week sediment toxicity tests were conducted with Hyalella azteca. The effects of metals and PAHs are discussed here; the effects of salts, nutrients, and water quality are discussed in a companion paper. Survival and growth of Hyalella after exposure to fall samples were variable: survival was significantly reduced (64-74% of controls) at three out of four sites, but there were no significant growth effects. More dramatic effects were observed after Hyalella were exposed to spring samples: survival was significantly reduced at the two sites furthest downstream (0-75% of controls), and growth was significantly lower in four out of five sites when comparing Hyalella exposed to site sediment with overlying site water versus site sediment with overlying control water. These seasonal changes in toxicity were not related to metals or PAHs: 1. levels of bioavailable metals were below those expected to cause toxicity, and 2. levels of PAHs in sediment were lowest at sites with the greatest toxicity and highest in water and sediment at sites with no toxicity. Although not associated with toxicity, some metals and PAHs exceeded probable and severe effect levels, and could be a cause for concern if contaminant bioavailability changes. Toxicity in the TWSMF appeared to be primarily associated with water-borne contaminants. The cause(s) of these effects

  16. Development of a Model, Metal-reducing Microbial Community for a System Biology Level Assessment of Desulfovibrio vulgaris as part of a Community

    Energy Technology Data Exchange (ETDEWEB)

    Elias, Dwayne; Schadt, Christopher; Miller, Lance; Phelps, Tommy; Brown, S. D.; Arkin, Adam; Hazen, Terry; Drake, Megin; Yang, Z.K.; Podar, Mircea

    2010-05-17

    One of the largest experimental gaps is between the simplicity of pure cultures and the complexity of open environmental systems, particularly in metal-contaminated areas. These microbial communities form ecosystem foundations, drive biogeochemical processes, and are relevant for biotechnology and bioremediation. A model, metal-reducing microbial community was constructed as either syntrophic or competitive to study microbial cell to cell interactions, cell signaling and competition for resources. The microbial community was comprised of the metal-reducing Desulfovibrio vulgaris Hildenborough and Geobacter sulfurreducens PCA. Additionally, Methanococcus maripaludis S2 was added to study complete carbon reduction and maintain a low hydrogen partial pressure for syntrophism to occur. Further, considerable work has been published on D. vulgaris and the D. vulgaris/ Mc. maripaludis co-culture both with and without stress. We are extending this work by conducting the same stress conditions on the model community. Additionally, this comprehensive investigation includes physiological and metabolic analyses as well as specially designed mRNA microarrays with the genes for all three organisms on one slide so as to follow gene expression changes in the various cultivation conditions as well as being comparable to the co- and individual cultures. Further, state-of -the-art comprehensive AMT tag proteomics allows for these comparisons at the protein level for a systems biology assessment of a model, metal-reducing microbial community. Preliminary data revealed that lactate oxidation by D. vulgaris was sufficient to support both G. sulfurreducens and M. maripaludis via the excretion of H2 and acetate. Fumarate was utilized by G. sulfurreducens and reduced to succinate since neither of the other two organisms can reduce fumarate. Methane was quantified, suggesting acetate and H2 concentrations were sufficient for M. maripaludis. Steady state community cultivation will allow for

  17. VH replacement in primary immunoglobulin repertoire diversification.

    Science.gov (United States)

    Sun, Amy; Novobrantseva, Tatiana I; Coffre, Maryaline; Hewitt, Susannah L; Jensen, Kari; Skok, Jane A; Rajewsky, Klaus; Koralov, Sergei B

    2015-02-01

    The genes encoding the variable (V) region of the B-cell antigen receptor (BCR) are assembled from V, D (diversity), and J (joining) elements through a RAG-mediated recombination process that relies on the recognition of recombination signal sequences (RSSs) flanking the individual elements. Secondary V(D)J rearrangement modifies the original Ig rearrangement if a nonproductive original joint is formed, as a response to inappropriate signaling from a self-reactive BCR, or as part of a stochastic mechanism to further diversify the Ig repertoire. VH replacement represents a RAG-mediated secondary rearrangement in which an upstream VH element recombines with a rearranged VHDHJH joint to generate a new BCR specificity. The rearrangement occurs between the cryptic RSS of the original VH element and the conventional RSS of the invading VH gene, leaving behind a footprint of up to five base pairs (bps) of the original VH gene that is often further obscured by exonuclease activity and N-nucleotide addition. We have previously demonstrated that VH replacement can efficiently rescue the development of B cells that have acquired two nonproductive heavy chain (IgH) rearrangements. Here we describe a novel knock-in mouse model in which the prerearranged IgH locus resembles an endogenously rearranged productive VHDHJH allele. Using this mouse model, we characterized the role of VH replacement in the diversification of the primary Ig repertoire through the modification of productive VHDHJH rearrangements. Our results indicate that VH replacement occurs before Ig light chain rearrangement and thus is not involved in the editing of self-reactive antibodies.

  18. Are Vicinal Metal Surfaces Stable?

    DEFF Research Database (Denmark)

    Frenken, J. W. M.; Stoltze, Per

    1999-01-01

    We use effective medium theory to demonstrate that the energies of many metal surfaces are lowered when these surfaces are replaced by facets with lower-index orientations. This implies that the low-temperature equilibrium shapes of many metal crystals should be heavily faceted. The predicted ins...

  19. Knee Replacement: What you can Expect

    Science.gov (United States)

    ... improves function lessen with each additional surgery. Artificial knees can wear out Another risk of knee replacement ... replacement surgery to last about two hours. After knee replacement surgery After surgery, you're wheeled to ...

  20. Homologous gene replacement in Physarum

    Energy Technology Data Exchange (ETDEWEB)

    Burland, T.G. [Univ. of Wisconsin, Madison, WI (United States); Pallotta, D. [Laval Univ., Quebec (Canada)

    1995-01-01

    The protist Physarum polycephalum is useful for analysis of several aspects of cellular and developmental biology. To expand the opportunities for experimental analysis of this organism, we have developed a method for gene replacement. We transformed Physarum amoebae with plasmid DNA carrying a mutant allele, ardD{Delta}1, of the ardD actin gene; ardD{Delta}1 mutates the critical carboxy-terminal region of the gene product. Because ardD is not expressed in the amoeba, replacement of ardD{sup +} with ardD{Delta}1 should not be lethal for this cell type. Transformants were obtained only when linear plasmid DNA was used. Most transformants carried one copy of ardD{Delta}1 in addition to ardD{sup +}, but in two (5%), ardD{sup +} was replaced by a single copy of ardD{Delta}1. This is the first example of homologous gene replacement in Physarum. ardD{Delta}1 was stably maintained in the genome through growth, development and meiosis. We found no effect of ardD{Delta}l on viability, growth, or development of any of the various cell types of Physarum. Thus, the carboxy-terminal region of the ardD product appears not to perform a unique essential role in growth or development. Nevertheless, this method for homologous gene replacement can be applied to analyze the function of any cloned gene. 38 refs., 6 figs., 1 tab.

  1. The instability of wrist joint and total wrist replacement

    Institute of Scientific and Technical Information of China (English)

    Jin-xing Ma; Yong-Qing Xu

    2016-01-01

    Total wrist arthroplasty are not used as widely as total knee and hip replacement.The functional hands are requiring surgeons to design a durable and functional satisfying prosthesis.This article will list the main reasons that cause the failure of the prosthesis.Some remarkable and representative prostheses are listed to show the devolvement of total wrist prosthesis and their individual special innovations to fix the problems,And the second part we will discuss the part that biomechanical elements act in the total wrist replacement (TWA).Summarize and find out what the real problem is and how we can find a way to fix it.

  2. Lower limb joint replacement in rheumatoid arthritis

    Directory of Open Access Journals (Sweden)

    Clement Nicholas D

    2012-06-01

    Full Text Available Abstract Introduction There is limited literature regarding the peri-operative and surgical management of patients with rheumatoid disease undergoing lower limb arthroplasty. This review article summarises factors involved in the peri-operative management of major lower limb arthroplasty surgery for patients with rheumatoid arthritis. Methods We performed a search of the medical literature, using the PubMed search engine (http://www.pubmed.gov. We used the following terms: ‘rheumatoid’ ‘replacement’ ‘arthroplasty’ and ‘outcome’. Findings The patient should be optimised pre-operatively using a multidisciplinary approach. The continued use of methotrexate does not increase infection risk, and aids recovery. Biologic agents should be stopped pre-operatively due the increased infection rate. Patients should be made aware of the increased risk of infection and periprosthetic fracture rates associated with their disease. The surgical sequence is commonly hip, knee and then ankle. Cemented total hip replacement (THR and total knee replacement (TKR have superior survival rates over uncemented components. The evidence is not clear regarding a cruciate sacrificing versus retaining in TKR, but a cruciate sacrificing component limits the risk early instability and potential revision. Patella resurfacing as part of a TKR is associated with improved outcomes. The results of total ankle replacement remain inferior to THR and TKR. RA patients achieve equivalent pain relief, but their rehabilitation is slower and their functional outcome is not as good. However, the key to managing these complicated patients is to work as part of a multidisciplinary team to optimise their outcome.

  3. Cobra Probes Containing Replaceable Thermocouples

    Science.gov (United States)

    Jones, John; Redding, Adam

    2007-01-01

    A modification of the basic design of cobra probes provides for relatively easy replacement of broken thermocouples. Cobra probes are standard tube-type pressure probes that may also contain thermocouples and that are routinely used in wind tunnels and aeronautical hardware. They are so named because in side views, they resemble a cobra poised to attack. Heretofore, there has been no easy way to replace a broken thermocouple in a cobra probe: instead, it has been necessary to break the probe apart and then rebuild it, typically at a cost between $2,000 and $4,000 (2004 prices). The modified design makes it possible to replace the thermocouple, in minimal time and at relatively low cost, by inserting new thermocouple wire in a tube.

  4. Testing the electrostatic characteristics of polypropylene fabric with metallic yarns, intended for use in coal mines threatened by the explosion hazard. Part 2: Tests in coal mine

    Science.gov (United States)

    Talarek, M.; Orzech, L.

    2011-06-01

    The aim of this paper was to assess the electrostatic safety of polypropylene fabric with metallic yarns intended for use in coal mines. Such fabrics have not been used in the Polish mining industry yet. The tests conducted have been divided into two subgroups: laboratory tests and tests in a coal mine. This paper presents the results of tests in a coal mine, where we have focused on the resistance-to-ground in some specific situations. Bags made of fabric at the roadway face were tested, as well as the roll of fabric during transport and carried by a miner. The results obtained allow the reliable assessment of the risk of using fabrics with metallic yarns in the explosive atmosphere which often occurs in coal mines.

  5. Testing the electrostatic characteristics of polypropylene fabric with metallic yarns, intended for use in coal mines threatened by the explosion hazard. Part 2: Tests in coal mine

    Energy Technology Data Exchange (ETDEWEB)

    Talarek, M; Orzech, L, E-mail: mtalarek@komag.eu [KOMAG Institute of Mining Technology, Pszczynska 37, 44-101 Gliwice (Poland)

    2011-06-23

    The aim of this paper was to assess the electrostatic safety of polypropylene fabric with metallic yarns intended for use in coal mines. Such fabrics have not been used in the Polish mining industry yet. The tests conducted have been divided into two subgroups: laboratory tests and tests in a coal mine. This paper presents the results of tests in a coal mine, where we have focused on the resistance-to-ground in some specific situations. Bags made of fabric at the roadway face were tested, as well as the roll of fabric during transport and carried by a miner. The results obtained allow the reliable assessment of the risk of using fabrics with metallic yarns in the explosive atmosphere which often occurs in coal mines.

  6. 1,3,4-thiadiazole derivatives. Part 9. Synthesis and biological activity of metal complexes of 5-(2-aminoethyl)-2-amino-1,3,4-thiadiazole.

    Science.gov (United States)

    Barboiu, M; Cimpoesu, M; Guran, C; Supuran, C T

    1996-01-01

    Metal complexes of the title ligand (L) containing Co(II), Ni(II) and Cu(II) were prepared and characterized by elemental analysis, IR, electronic spectroscopy and conductimetry. The new derivatives, possessing the following formulae, CuL(2)(OH)(2), NiL(2)Cl(2), and [Co(2)LCl(4)](n) showed in vitro antifungal activity against Aspergillus and Candida spp.

  7. Perform MetalMapper Classification Treatability Investigations as Part of Remedial Investigation/Feasibility Studies: Live Site Demonstrations: Pueblo Chemical Depot

    Science.gov (United States)

    2016-03-14

    test pit and IVS data collection, preprocessing, initial target selections, non-equipment direct costs (per diem, hotel , truck rental tractor, GPS...equipment direct costs (per diem, hotel , truck rental, fuel, etc.). Instrument rental costs : MetalMapper, tractor, GPS, etc. All processing and...Environmental Security Technology Certification Program (ESTCP). The publication of this report does not indicate endorsement by the Department of

  8. 1,3,4-Thiadiazole Derivatives. Part 91. Synthesis and Biological Activity of Metal Complexes of 5-(2-Aminoethyl)-2-Amino-1,3,4-Thiadiazole

    Science.gov (United States)

    Barboiu, Mihai; Cimpoesu, Marilena; Guran, Cornelia

    1996-01-01

    Metal complexes of the title ligand (L) containing Co(II), Ni(II) and Cu(II) were prepared and characterized by elemental analysis, IR, electronic spectroscopy and conductimetry. The new derivatives, possessing the following formulae, CuL2(OH)2, NiL2Cl2, and [Co2LCl4]n showed in vitro antifungal activity against Aspergillus and Candida spp. PMID:18472898

  9. Prioritization methodology for chemical replacement

    Science.gov (United States)

    Goldberg, Ben; Cruit, Wendy; Schutzenhofer, Scott

    1995-01-01

    This methodology serves to define a system for effective prioritization of efforts required to develop replacement technologies mandated by imposed and forecast legislation. The methodology used is a semi quantitative approach derived from quality function deployment techniques (QFD Matrix). QFD is a conceptual map that provides a method of transforming customer wants and needs into quantitative engineering terms. This methodology aims to weight the full environmental, cost, safety, reliability, and programmatic implications of replacement technology development to allow appropriate identification of viable candidates and programmatic alternatives.

  10. Wafer Replacement Cluster Tool (Presentation);

    Energy Technology Data Exchange (ETDEWEB)

    Branz, H. M.

    2008-04-01

    This presentation on wafer replacement cluster tool discusses: (1) Platform for advanced R and D toward SAI 2015 cost goal--crystal silicon PV at area costs closer to amorphous Si PV, it's 15% efficiency, inexpensive substrate, and moderate temperature processing (<800 C); (2) Why silicon?--industrial and knowledge base, abundant and environmentally benign, market acceptance, and good efficiency; and (3) Why replace wafers?--expensive, high embedded energy content, and uses 50-100 times more silicon than needed.

  11. Development of casting investment preventing blackening of noble metal alloys part 1. Application of developed investment for Ag-Pd-Cu-Au alloy.

    Science.gov (United States)

    Kakuta, Kiyoshi; Nakai, Akira; Goto, Shin-ichi; Wakamatsu, Yasushi; Yara, Atushi; Miyagawa, Yukio; Ogura, Hideo

    2003-03-01

    The objective of this study is to develop a casting investment that prevents the blackening of the cast surface of noble metal alloys. The experimental investments were prepared using a gypsum-bonded investment in which the metallic powders such as boron (B), silicon (Si), aluminum (Al) and titanium (Ti) were added as oxidizing agents. An Ag-Pd-Cu-Au alloy was cast into the mold made of the prepared investment. The effect of the addition of each metal powder was evaluated from the color difference between the as-cast surface and the polished surface of the cast specimen. The color of the as-cast surface approached that of the polished surface with increasing B and Al content. A lower mean value in the color difference was obtained at 0.25-1.00 mass% B content. B and Al are useful as an additive in a gypsum-bonded investment to prevent the blackening of an Ag-Pd-Cu-Au alloy. The effects of Si and Ti powder addition could not be found.

  12. Research on corrosion resistance influencing factors of metal parts in outdoor condensing units%室外型冷凝机组金属部件耐腐蚀性能影响因素研究

    Institute of Scientific and Technical Information of China (English)

    苏梅

    2012-01-01

    Both the corrosion mechanism and the corrosion resistance influencing factors of the metal parts in outdoor units exposed in the air are summarized. Regarding the red rust area as the criterion, the experiments are made in order to judge the influence degree of the three important factors-metal backing,spray technology,coating thickness,and the pairwise interaction with the orthogonal experimental method. The results indicate that spray technology influences the corrosion resistance most. The metal backing, and the interaction of the metal backing and spray technology can influence the corrosion resistance obviously. Therefore, correctly selecting the spray technology, metal backing and taking their interaction into consideration are important for enhancing corrosion resistance of outdoor metal parts.%概述室外机金属部件暴露于大气中的腐蚀机制及金属部件耐腐蚀性能的影响因素.采用正交试验方法,以盐雾试验后的红锈面积作为判断标准,针对影响金属耐腐蚀性能的3个重要因素(金属基材、喷涂方式和涂膜厚度)及其两两交互作用对室外机金属部件耐腐蚀性能的影响程度进行试验对比.结果表明:喷涂方式对耐腐蚀性能影响最大,金属基材、金属基材与喷涂方式的交互作用对金属耐腐蚀性能影响较大.因此正确选择喷涂方式和金属基材并考虑2种影响因素的交互关系对提高室外机金属部件耐腐蚀性能具有重要意义.

  13. Structure and catalytic activity of metal complexes immobilized on supports. Part 1. The synthesis of palladium complexes on silica gel, modified by aldiminopropylheteryl groups, and their properties

    Energy Technology Data Exchange (ETDEWEB)

    Nesterov, M.A.; Lafer, L.I.; Dykh, Z.L.; Sharf, V.Z.; Yakerson, V.I.

    1987-07-10

    Based on silica gel containing a ..gamma..-aminopropyl group and ..cap alpha..-, ..beta..-, and ..gamma..-aldehydes of the heterocyclic series, supports having graft aldimine groups and their stable complexes with palladium have been obtained. It has been established by IR spectroscopy that the hydroxyl coating of silica gel is almost completely replaced by functional groups of ligands combined with the surface through O atoms. The Pd atom is coordinated by the N atom of the aldimine group, the heteroatom of the pyridine ring, and in the case of furan by the ..pi..-electrons of the ring. The catalytic activity and selectivity of Pd complexes in the isomerization and hydrogenation of allylbenzene is determined by the nature of the grafted heterocyclic ligand.

  14. 金属零件3D打印技术的应用研究%The Applications and Progress of Manufacturing of Metal Parts by 3 D Printing Technology

    Institute of Scientific and Technical Information of China (English)

    曾光; 韩志宇; 梁书锦; 张鹏; 陈小林; 张平祥

    2014-01-01

    Manufacturing of metal parts by 3D printing technology, as the most advanced and potential technology of 3D printing technologies, presents the most important direction of modern advanced manufacturing technologies .With the de-velopment of science and technology constantly demanding for materials , utilizing the rapid proto-typing technology to pro-duce metal functional parts directly will be the main research direction.3D printing technology is rapidly changing our tra-ditional production mode and life style.3D printing manufacturing technology, which is networked and personalized, will drive the third industrial revolution.Laser engineered net shaping (LENS), selective laser melting (SLM) and electron beam selective melting ( EBSM) are the typical representatives of the metal parts 3D printing technology.Based on the three types of technologies, the metal parts 3D printing technology and its basic principles and application fields are intro-duced.At last, the development prospect of the printing technology is discussed .%金属零件3D打印技术作为整个3D打印体系中最为前沿和最具潜力的技术,是目前先进制造技术的重要发展方向。随着科技发展对材料的不断需求,利用快速成形技术直接制造金属功能零件将会成为该技术的主要发展方向。3D打印技术正在快速改变着人们传统的生产方式和生活方式。以数字化、网络化、个性化、定制化为特点的3D打印制造技术被外界认为将推动第三次工业革命。激光工程化净成形技术(LENS),激光选区熔化技术(SLM)及电子束选区熔化技术(EBSM)3种技术是金属零件3D打印技术的典型代表。对金属零件3D打印技术,包括基本的技术原理及其技术应用领域进行了介绍,最后对金属零件3D打印技术的发展进行了展望。

  15. Replacement policies for dairy cows

    DEFF Research Database (Denmark)

    Nielsen, Lars Relund

    In a recent paper a hierarchical Markov decision processes (MDP) with finite state and action space was formulated for the dairy cow replacement problem with stage lengths of 1 d. Bayesian updating was used to predict the performance of each cow in the herd and economic decisions were based...

  16. Bonding over Dentin Replacement Materials.

    Science.gov (United States)

    Meraji, Naghmeh; Camilleri, Josette

    2017-08-01

    Dentin replacement materials are necessary in large cavities to protect the pulp and reduce the bulk of filling material. These materials are layered with a composite resin restorative material. Microleakage caused by poor bonding of composite resin to underlying dentin replacement material will result in pulp damage. The aim of this study was to characterize the interface between dentin replacement materials and composite resin and to measure the shear bond strength after dynamic aging. Biodentine (Septodont, Saint Maur-des-Fosses, France), Theracal LC (Bisco, Schaumburg, IL), and Fuji IX (GC, Tokyo, Japan) were used as dentin replacement materials. They were then overlaid with a total-etch and bonding agent or a self-etch primer and composite resin or a glass ionomer cement. All combinations were thermocycled for 3000 cycles. The interface was characterized using scanning electron microscopy and elemental mapping. Furthermore, the shear bond strength was assessed. The Biodentine surface was modified by etching. The Theracal LC and Fuji IX microstructure was unchanged upon the application of acid etch. The Biodentine and glass ionomer interface showed an evident wide open space, and glass particles from the glass ionomer adhered to the Biodentine surface. Elemental migration was shown with aluminum, barium, fluorine, and ytterbium present in Biodentine from the overlying composite resin. Calcium was more stable. The bond strength between Theracal LC and composite using a total-etch technique followed by self-etch primer achieved the best bond strength values. Biodentine exhibited the weakest bond with complete failure of bonding shown after demolding and thermocycling. Dynamic aging is necessary to have clinically valid data. Bonding composite resin to water-based dentin replacement materials is still challenging, and further alternatives for restoration of teeth using such materials need to be developed. Copyright © 2017 American Association of Endodontists

  17. 金属零件自动超轻结构化设计及激光增材制造%Automatic design and laser additive manufacturing of super-light structure of metal part

    Institute of Scientific and Technical Information of China (English)

    吴伟辉; 肖冬明; 毛星

    2016-01-01

    为解决金属超轻结构零件设计技术复杂、设计周期长、难添加蒙皮进行增材制造等难题,提出一种基于激光选区熔化增材制造工艺的金属零件自动超轻结构化设计方法:根据激光选区熔化工艺特点,编制程序将原始零件CAD模型自动转化为设定孔隙率的带蒙皮类蜂窝状超轻结构零件模型,且其数据可直接驱动设备实现零件增材制造.研究了带蒙皮超轻结构的构造形式及设计方法;探讨了合适的成型棱长及合理蒙皮结构形式;成功实现复杂零件自动带蒙皮超轻结构化设计及增材制造,所得零件孔隙率误差2.79%,表明能较准确按预期减重.该方法能根据原始零件CAD模型自动、快速地构建带蒙皮金属超轻结构零件模型,大大减轻该类零件设计负担及提高其实用性.%In order to solve the problems when designing super-light structure part such as needing complex design techniques, long design cycle, difficult to add skin if making it by additive manufacturing technology, based on selective laser melting technology, a method which can automatically add skinned super-light structure to traditional metal part CAD model was put forward in this paper. Considering the selective laser melting process characteristics, through an algorithm, a skinned super-light quasi-honeycomb structure part model with a preset porosity can be automatically designed by transforming an original CAD model. And the new part model data format can direct drive a selective laser melting machine for additive manufacturing without any data format transformation. The construction and design method of the skinned super-light structure of metal part were studied. Through process analysis, appropriate processing unit length and reasonable skin tissue of super-light structure metal part were gotten. The above method was tested successfully on a part model with complex shape in a selective laser melting experiment. The error of

  18. Interdiffusion behavior of tungsten or rhenium and group 5 and 6 elements and alloys of the periodic table, part 1. [at dissimilar metal joints

    Science.gov (United States)

    Arcella, F. G.

    1974-01-01

    Arc cast W, CVD W, CVD Re, and powder metallurgy Re materials were hot isostatically pressure welded to ten different refractory metals and alloys (Cb, Cb-1Zr, Ta, Ta-10W, T-111, ASTAR-811C, W-25Re, Mo-50Re, W-30Re-20Mo, ect.) and thermally aged at 10 to the minus 8th power torr at 1200, 1500, 1630, 1800, and 2000 C for 100 to 2000 hours. Electron beam microprobe analysis was used to characterize the interdiffusion zone width of each couple system as a function of age time and temperature. Extrapolations of interdiffusion zone thickness to 10,000 hours were made. Classic interdiffusion analysis was performed for several of the systems by Boltzmann-Matano analysis. A method of inhibiting Kirkendall voids from forming during thermal ageing of dissimilar metal junctions was devised and experimentally demonstrated. An electron beam weld study of Cb-1Zr to Re and W-25Re demonstrated the limited acceptability of these welds.

  19. The Use of Adsorbent Materials of Improving the Characteristics of Polluted Soils, Part 2 the Bioaccumulation of Metals in Plants Used in Phytoremediation Processes

    Directory of Open Access Journals (Sweden)

    Florica Morariu

    2015-05-01

    Full Text Available The study covers the advantages of phytoremediation processes of soils heavily polluted with total petroleum hydrocarbon (TPH with the use of Linum usitatissimum (flax. To increase the potential development of technical crops on TPH soils polluted with 74.12 ± 3.5 g·kg-1 D.M., the contaminated soils were amended with fly ash; the ratio of polluted soil: fly ash 12:1 wt. / wt. and fertilized with sewage sludge. The degree of accumulation of Fe in the stems was 21 - 33 % higher than in the control sample and 6 - 27 % in the seeds; the accumulation of Mn in the stems was 13.5 - 30 % higher than in the control sample and 8 - 17 % in the seeds; the accumulation of Cu in stems was 17 - 6 % higher than in the control sample and for seeds 20 - 60 %; the accumulation of Zn in stems was 13 - 27 % higher than in the control sample with 49 - 63 % in the seeds. In the harvested plant tissues from the studied variants the content of heavy metals Cd, Cr, Pb and Ni was less than the detection limit. Monitoring bioaccumulation of heavy metals in aerial plant tissue was needed to decide the sector where the biomass harvested from TPH polluted soil covered with vegetation.

  20. Digital control of pulsed gas metal arc welding inverter using TMS320LF2407A

    Institute of Scientific and Technical Information of China (English)

    Wu Kaiyuan; Huang Shisheng; Li Xinglin; Wu Shuifeng

    2008-01-01

    A digital control of pulsed gas metal arc welding inverter was proposed. A control system consisting of analogue parts was replaced with a new digital control implemented in a TMS320LF2407A DSP chip. The design and constructional features of the whole digital control were presented. The resources of the DSP chip were efficiently utilized and the circuits are very concise, which can enhance the stability and reliability of welding inverter. Experimental results demonstrate that the developed digital control has the ability to accomplish the excellent pulsed gas metal arc welding process and the merits of the developed digital control are stable welding process, little spatter and perfect weld appearance.

  1. Stratigraphic sections, depositional environments, and metal content of the upper part of the Middle Pennsylvanian Minturn Formation, Northern Sangre De Cristo Range, Custer and Saguache counties, Colorado

    Science.gov (United States)

    Clark, R.F.; Walz, D.M.

    1985-01-01

    The calcareous upper part of the 2,000-meter-thick Middle Pennsylvanian Minturn Formation (Lindsey and others, 1985) in the northern Sangre de Cristo Range is a key stratigraphic interval for correlating rocks and mapping the structure of the range. The stratigraphy of this complex and heretofore poorly known interval is reported here in order to provide a basis for correlation among the structural blocks in the range. Inferred depositional environments of the upper part of the Minturn Formation are described briefly.

  2. Synthetic Versus Tissue-Engineered Implants for Joint Replacement

    Directory of Open Access Journals (Sweden)

    Duncan E. T. Shepherd

    2007-01-01

    Full Text Available Human synovial joints are remarkable as they can last for a lifetime. However, they can be affected by disease that may lead to destruction of the joint surface. The most common treatment in the advanced stages of joint disease is artificial joint replacement, where the diseased synovial joint is replaced with an artificial implant made from synthetic materials, such as metals and polymers. A new technique for repairing diseased synovial joints is tissue engineering where cells are used to grow replacement tissue. This paper explores the relative merits of synthetic and tissue-engineered implants, using joint replacement as an example. Synthetic joint replacement is a well-established procedure with the advantages of early mobilisation, pain relief and high patient satisfaction. However, synthetic implants are not natural tissues; they can cause adverse reactions to the body and there could be a mismatch in mechanical properties compared to natural tissues. Tissue-engineered implants offer great potential and have major advantages over synthetic implants as they are natural tissue, which should ensure that they are totally biocompatible, have the correct mechanical properties and integrate well with the existing tissue. However, there are still many limitations to be addressed in tissue engineering such as scaling up for production, bioreactor design, appropriate regulation and the potential for disease to attack the new tissue-engineered implant.

  3. The Status and Progress of Manufacturing of Metal Parts by 3D Printing Technology%金属零件3D打印技术现状及研究进展*

    Institute of Scientific and Technical Information of China (English)

    杨永强; 刘洋; 宋长辉

    2013-01-01

      简述了国内外的金属零件3D打印技术的研究现状及最新进展,包括选区激光熔化(Selective Laser Melting, SLM)技术、激光近净成形(Laser Engineered Net Shaping, LENS)技术和电子束选区熔化(Electron Beam Selective Melting, EBSM)技术,并针对作者实验室的工作方向——SLM直接制造,具体分析了金属零件3D打印技术研究热点和难点以及具体应用。%This paper presents the research status and new progress of the metal parts manufactured by 3DP Technologies,including Selective Laser Melting(SLM),Laser Engineered Net Shaping(LENS) and Electron Beam Selective Melting(EBSM). At last,combined with the work of authors’ research team,the authors analyze the main research hotspots ,problems and oriented applications of metal parts manufactured by 3DP Technologies in detail.

  4. Spectroscopic and Electrochemical Studies of the Transition Metal Tetrasulfonated Phthalocyanines. Part 5. Voltammetric Studies of Adsorbed Tetrasulfonated Phthalocyanines (MTsPc) in Aqueous Solutions.

    Science.gov (United States)

    1985-10-01

    Reserve University and the York University groups. IS. SUPPLEMENTARY NOTES Accepted for publication in the Journalof Electroanalytical Chemistry and... Electroanalytical Chemistry and Interfacial Electrochemistry October 1, 1985 Reproduction in whole or in part is permitted for any purpose of the United

  5. Material characterization and evaluation of Fyrquel effect on the metal part of filters in a system EHC; Caracterizacion del material y evaluacion del efecto del Fyrquel en la parte metalica de filtros en un sistema EHC

    Energy Technology Data Exchange (ETDEWEB)

    Diaz S, A.; Zenteno S, J.; Robles P, E.; Contreras R, A.; Arganis J, C. [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico); Griz C, M., E-mail: angeles.diaz@inin.gob.mx [Comision Federal de Electricidad, Central Nucleoelectrica Laguna Verde, Carretera Cardel-Nautla Km. 42.5, Veracruz (Mexico)

    2014-10-15

    In recent years, unexpected stoppages in power plants have been associated with problems in electro-hydraulic control systems (EHC) which generally operate with fluids to high pressure resistant to fire, but sensitive to the presence of water and contaminants that can promote damage and malfunction of government and discharge valves. The analysis here presented was performed to two filters prior to the servo valves of an EHC system that came out of service as a result of damage to these components. The study is based on analysis and inspection of metal and filter elements of these devices, integrating both chemical characterization by energy-dispersive X-ray spectroscopy of waste as materials that comprise both filters. The assessment made allowed documenting a poor design of the devices, same that promoted the stagnant fluid (Fyrquel), locally modifying the chemical composition of the medium, prompting the activation of auto-catalytic degradation processes that acidified the environment; the acid ph solutions began in susceptible sites of electrochemical corrosion processes which increased the Fyrquel contamination. (Author)

  6. 姜黄各药用部位对土壤中重金属的富集能力分析%Determination of Absorptive Ability to the Heavy Metals in Different Parts of Rhizoma Curcumae Longae

    Institute of Scientific and Technical Information of China (English)

    周亚文; 刘璐; 何越; 吕瑞

    2015-01-01

    Objective:Explore the absorption of heavy metals in soil by plant Curcuma Longa, The aim of the research was to provide basis for non-pollution cultivation of plant Curcumae Longae. Method:The flame atomic absorption spectrometric was applied to determine the heavy metal including Cu, Pb and Cd and the absorptive ability of the heavy metals was evaluated. Results:The quantization result showed that the concentrated coefficient of Rhizoma Curcumae Longae to the Cu, Pb, Cd was varied, in which the order for absorptive ability of Curcumae Longae L. was Pbmetals in different part of Rhizoma Curcumae Longae. The result can give some useful information for the GAP cultivation of Rhizoma Curcumae Longae.%目的:探究植株姜黄对土壤中重金属的吸收富集情况,为植株姜黄的规范化栽培提供依据。方法:采用火焰原子吸收光谱法测定姜黄、黄丝郁金及其栽培土壤中Cu,Pb,Cd三种重金属元素的含量,并评价各部位对重金属元素的富集能力。结果:姜黄各部位对重金属元素的富集能力有一定差异,其中根茎对重金属的富集能力依次是Pb

  7. Urbanization, Ikization, and Replacement Dynamics

    CERN Document Server

    Chen, Yanguang

    2015-01-01

    The phenomenon of Iks was first found by anthropologists and biologists, but it is actually a problem of human geography. However, it has not yet drawn extensive attention of geographers. In this paper, a hypothesis of ikization is presented that sudden and violent change of geographical environments results in dismantling of traditional culture, which then result in collective depravity of a nationality. By quantitative analysis and mathematical modeling, the causality between urbanization and ikization is discussed, and the theory of replacement dynamics is employed to interpret the process of ikization. Urbanization is in essence a nonlinear process of population replacement. Urbanization may result in ikization because that the migration of population from rural regions to urban regions always give rise to abrupt changes of geographical environments and traditional culture. It is necessary to protect the geographical environment against disruption, and to inherit and develop traditional culture in order t...

  8. [MINIMALLY INVASIVE AORTIC VALVE REPLACEMENT].

    Science.gov (United States)

    Tabata, Minoru

    2016-03-01

    Minimally invasive aortic valve replacement (MIAVR) is defined as aortic valve replacement avoiding full sternotomy. Common approaches include a partial sternotomy right thoracotomy, and a parasternal approach. MIAVR has been shown to have advantages over conventional AVR such as shorter length of stay and smaller amount of blood transfusion and better cosmesis. However, it is also known to have disadvantages such as longer cardiopulmonary bypass and aortic cross-clamp times and potential complications related to peripheral cannulation. Appropriate patient selection is very important. Since the procedure is more complex than conventional AVR, more intensive teamwork in the operating room is essential. Additionally, a team approach during postoperative management is critical to maximize the benefits of MIAVR.

  9. Effect of Crystallinity on Electrochemical Insertion/Extraction of Li in Transition Metal Oxides Part II: TiO2, V2O5 and MoOs

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Electrochemical irtsertion/extraction of Li on cathode materials of anatase type TiO2, quasilayered structure V2O5 and layered structure MoO3 was measured on samples of which structures were well characterized and showed a wide range of crystallinity. On the basis of experimental results on structure, morphology and charge-discharge characteristics, the effect of crystallinity of the cathode materials on electrochemical Li insertion/extraction performance was discussed.These three transition metal oxides were classified as one group on the basis of whether the crystallirfity of these oxides affects to the performance or not; LiMn2O4 and LiCo0.5Ni0.5O2belongs to the former group and TiO2, V2O5 and MoO3 to the latter.

  10. Mitochondrial Replacement: Ethics And Identity

    OpenAIRE

    Wrigley, Anthony; Wilkinson, Stephen; Appleby, John B

    2015-01-01

    Mitochondrial replacement techniques (MRTs) have the potential to allow prospective parents who are at risk of passing on debilitating or even life-threatening mitochondrial disorders to have healthy children to whom they are genetically related. Ethical concerns have however been raised about these techniques. This article focuses on one aspect of the ethical debate, the question of whether there is any moral difference between the two types of MRT proposed: Pronuclear Transfer (PNT) and Mat...

  11. Electrochemical capacitance of Ni-doped metal organic framework and reduced graphene oxide composites: more than the sum of its parts.

    Science.gov (United States)

    Banerjee, Parama Chakraborty; Lobo, Derrek E; Middag, Rick; Ng, Woo Kan; Shaibani, Mahdokht E; Majumder, Mainak

    2015-02-18

    Composites of a Ni-doped metal organic framework (MOF) with reduced graphene oxide (rGO) are synthesized in bulk (gram scale) quantities. The composites are composed of rGO sheets, which avoid restacking from the physical presence of MOF crystals. At larger concentration of rGO, the MOF crystals are distributed on the overlapping and continuous rGO sheets. Ni in Ni-doped MOF is found to engage in a two-electron, reversible, efficient, redox reaction shuttling between Ni and Ni(OH)2 in aqueous potassium hydroxide (KOH) electrolyte. The reaction is rather unique as Ni-based supercapacitors use a one-electron transfer Faradaic redox reaction between Ni(OH)2 and NiO(OH). Employing electrochemical impedance spectroscopy, we determined the charge transfer resistance to be 184 mΩ for MOF, 74 mΩ for a Ni-doped MOF and 6 mΩ for a rGO-Ni-doped MOF composite, but these modifications do not affect the mass transfer resistance. This novel redox reaction in conjunction with the lowered charge transfer resistance from the introduction of rGO underpins the synergy that dramatically increases the capacitance to 758 F/g in the rGO-Ni-doped MOF composite, when the parent MOF could store only 100 F/g and a physical composite of rGO and Ni-doped MOF could algebraically achieve about 240 F/g. A generic approach of doping MOFs with a redox active metal and forming a composite with rGO transforms an electro-inactive MOF to high capacity energy storage material with energy density of 37.8 Wh/kg at a power density of 227 W/kg. These results can promote the development of high-performance energy storage materials from the wide family of MOFs available.

  12. Limitations to fluid replacement during exercise.

    Science.gov (United States)

    Maughan, R J; Leiper, J B

    1999-04-01

    Fluid replacement during exercise is essential for endurance exercise performance and reducing the risk of heat illness. Fluids supply water, which ameliorates dehydration, and also substrate for the working muscles. Absorption of water and nutrients occurs in the upper part of the small intestine, and replacement may be limited by the rate at which fluid is emptied from the stomach or absorbed in the intestine. Gastric emptying of liquids is influenced primarily by the volume of fluid in the stomach and by its energy density. Increasing the volume will speed emptying, but increasing the nutrient content will slow emptying. Osmolality, temperature, and pH of drinks, as well as exercise intensity, are of minor importance. Intestinal water absorption is a passive process: water follows osmotic gradients but will also follow the active absorption of nutrients, especially glucose, which is actively co-transported with sodium. Water transport is maximised by the presence in the intestine of hypotonic solutions of glucose and sodium. Hypertonic solutions promote net water secretion into the intestinal lumen, resulting in a temporary net loss of water from the body. The amount of fluid ingested by athletes is normally much less than can be tolerated, therefore issues such as palatability and practising drinking during training are important.

  13. Results of Austin Moore replacement.

    Directory of Open Access Journals (Sweden)

    Jadhav A

    1996-04-01

    Full Text Available Forty cases of Austin Moore Replacement done for transcervical fractures of the femur in patients were reviewed after a period of 12 to 48 months postoperatively (mean 26 mth. 30 cases (75% had mild to severe pain of non-infective origin, starting as early as 6 months postoperatively. This was irrespective of the make, size or position (varus/valgus of the prosthesis. Though the Aufranc and Sweet clinical scoring was satisfactory in 65% cases, radiological evidence of complications like sinking, protrusion, etc. were seen in majority of the cases. Calcar resorption was seen in 34 cases (85% as early as 4 months postoperatively. Results of THR and bipolar replacement done for transcervical fractures in recent literature show 85% pain-free cases at 5 years. We feel that Austin Moore Replacement should be reserved for patients more than 65 years of age and those who are less active or debilitated because of other factors, because of increased acetabular wear with time in the younger individual. This is corroborated by unsatisfactory results in patients less than 65 years of age (p < 0.05.

  14. The caudal septum replacement graft.

    Science.gov (United States)

    Foda, Hossam M T

    2008-01-01

    To describe a technique for reconstructing the lost tip support in cases involving caudal septal and premaxillary deficiencies. The study included 120 patients with aesthetic and functional nasal problems resulting from the loss of caudal septal and premaxillary support. An external rhinoplasty approach was performed to reconstruct the lost support using a cartilaginous caudal septum replacement graft and premaxillary augmentation with Mersilene mesh. The majority of cases (75%) involved revisions in patients who had previously undergone 1 or more nasal surgical procedures. A caudal septum replacement graft was combined with premaxillary augmentation in 93 patients (77.5%). The mean follow-up period was 3 years (range, 1-12 years). The technique succeeded in correcting the external nasal deformities in all patients and resulted in a significant improvement in breathing in 74 patients (86%) with preoperative nasal obstruction. There were no cases of infection, displacement, or extrusion. The caudal septum replacement graft proved to be very effective in restoring the lost tip support in patients with caudal septal deficiency. Combining the graft with premaxillary augmentation using Mersilene mesh helped increase support and stability over long-term follow-up.

  15. A Fully Non-Metallic Gas Turbine Engine Enabled by Additive Manufacturing Part I: System Analysis, Component Identification, Additive Manufacturing, and Testing of Polymer Composites

    Science.gov (United States)

    Grady, Joseph E.; Haller, William J.; Poinsatte, Philip E.; Halbig, Michael C.; Schnulo, Sydney L.; Singh, Mrityunjay; Weir, Don; Wali, Natalie; Vinup, Michael; Jones, Michael G.; Patterson, Clark; Santelle, Tom; Mehl, Jeremy

    2015-01-01

    The research and development activities reported in this publication were carried out under NASA Aeronautics Research Institute (NARI) funded project entitled "A Fully Nonmetallic Gas Turbine Engine Enabled by Additive Manufacturing." The objective of the project was to conduct evaluation of emerging materials and manufacturing technologies that will enable fully nonmetallic gas turbine engines. The results of the activities are described in three part report. The first part of the report contains the data and analysis of engine system trade studies, which were carried out to estimate reduction in engine emissions and fuel burn enabled due to advanced materials and manufacturing processes. A number of key engine components were identified in which advanced materials and additive manufacturing processes would provide the most significant benefits to engine operation. The technical scope of activities included an assessment of the feasibility of using additive manufacturing technologies to fabricate gas turbine engine components from polymer and ceramic matrix composites, which were accomplished by fabricating prototype engine components and testing them in simulated engine operating conditions. The manufacturing process parameters were developed and optimized for polymer and ceramic composites (described in detail in the second and third part of the report). A number of prototype components (inlet guide vane (IGV), acoustic liners, engine access door) were additively manufactured using high temperature polymer materials. Ceramic matrix composite components included turbine nozzle components. In addition, IGVs and acoustic liners were tested in simulated engine conditions in test rigs. The test results are reported and discussed in detail.

  16. Metal-on-metal hip arthroplasty : local tissue reactions and clinical outcome

    NARCIS (Netherlands)

    Weegen, Walter van der

    2014-01-01

    Hip replacements using a metal-on-metal (MoM) bearing surface were reintroduced with the promise of low wear rates and easy revision in case of the resurfacing design. Although initially mid-term results were promising, local adverse soft tissure reactions to metal debris were detected around the ye

  17. Experimental replacement of aragonite by hydroxyapatite

    Science.gov (United States)

    Kasioptas, A.; Perdikouri, C.; Geisler, T.; Putnis, A.

    2009-04-01

    Hydrothermal treatment of aragonite with (NH4)2HPO4 solution has been shown to produce hydroxyapatite (HAP) with an overall identical and thus pre-determined morphology (Kasioptas et al, 2008). The preservation of the morphology is an outcome of the pseudomorphic nature of this particular reaction. We have investigated the mechanism of the replacement of aragonite by HAP using single, natural, inorganic aragonite crystals. Isothermal experiments were carried out with small crystals placed and sealed in autoclaves with (NH4)2HPO4 solution. After the experiments the aragonite crystals are partly replaced by a new phase. X-ray powder diffraction confirmed that the product phase is indeed HAP; however electron microprobe measurements revealed that the HAP is probably non-stoichiometric. Even when completely converted to HAP, scanning electron microscopy showed that the fine-structure of the aragonite has perfectly been retained. It was also observed that the HAP product phase exhibited a high porosity and was separated from the aragonite parent phase by a sharp interface (on the micrometer scale). The replacement of aragonite by HAP in an aqueous solution can be described in terms of a coupled dissolution-reprecipitation mechanism that takes place at an inward moving reaction front (Putnis& Putnis, 2007). The porosity in the HAP product phase allows the solution to reach the reaction interface. In addition, we have performed experiments with (NH4)2HPO4 solutions prepared with H2O enriched with 97 at.% 18O. The solutions were pre-heated separately to equilibrate the oxygen isotopes in the solution. Raman spectroscopy of the HAP product was used to identify the different vibration modes in the PO43-molecule due to the exchange of 16O with 18O atoms. Apart from the main ?1(PO4) band located near 962 cm-1, we observed four new bands near 945, 931, 919 and 908 cm-1. We have attributed the generation of these new bands to four different degrees of 18O atomic substitutions in

  18. Fusion following failed total ankle replacement.

    Science.gov (United States)

    Wünschel, Markus; Leichtle, Ulf G; Leichtle, Carmen I; Walter, Christian; Mittag, Falk; Arlt, Eva; Suckel, Andreas

    2013-04-01

    Although mid- to long-term results after total ankle replacement have improved because of available second- and third-generation devices, failure of total ankle replacement is still more common compared with total hip replacement and total knee replacement. The portfolio of available total ankle replacement revision component options is small. Furthermore, the bone stock of the tibiotalar region is scarce making it difficult and in some situations impossible to perform revision total ankle replacement. In these cases tibiotalar and tibiotalocalcaneal fusions are valuable options. This article describes which surgical procedures should be performed depending on the initial situation and gives detailed advice on surgical technique, postoperative care, and clinical results.

  19. Heavy metals pollution assessment of edible parts of crops grown around e-waste disassembling areas%电子垃圾拆解区农作物可食部重金属污染评价

    Institute of Scientific and Technical Information of China (English)

    周翠; 杨祥田; 何贤彪; 安玲瑶; 刘领

    2011-01-01

    A survey on the heavy metal contents in edible parts was conducted for crops grown around e-waste disassembling areas. The results showed that the heavy metal concentrations in the edible parts were 0. 08 - 10. 56 mg·kg-1 for Cr, 0. 02 -0. 76 mg·kg-1 for Cd, and 0. 05 - 1. 51 mg·kg-1 for Pb. The assessment of single factor pollution indexes indicated that the Pb pollution was most severe, with the pollution rate being 56. 52% , while pollution rate of Cr and Cd were 39. 13% and 34. 78% , respectively. Comprehensive pollution index indicated that 65. 22% of the crops were polluted, with the medium and heavy pollution grade being 13. 04% and 30.43% , respectively. The absorption and accumulation of heavy metals had interspecific and intraspecific differences. Among the crops, the levels of heavy metal pollution could be ranked in the order from low to high as follows: cereals < beans < potatoes < vegetables.%对电子垃圾拆解区的农作物可食部的重金属含量进行分析和评价.结果表明:Cr,Cd和Pb的含量范围分别为0.08 ~ 10.56,0.02 ~0.76和0.05~1.51 mg·kg-1;从单项污染指数来看,Pb的污染最为严重,达到56.52%,Cd和Cr的污染相对较轻,分别为39.13%和34.78%;从综合污染指数来看,65.22%的农作物可食部受到污染,其中中度和重度污染分别达到13.04%和30.43%,以重度污染为主.不同农作物对重金属的吸收和积累存在着较大差异,同一种农作物的不同品种之间的重金属含量也存在着较大差异.总之,各类农作物综合污染水平:谷类<豆类<薯类<蔬菜类.

  20. System efficiency for two-step metal oxide solar thermochemical hydrogen production – Part 2: Impact of gas heat recuperation and separation temperatures

    KAUST Repository

    Ehrhart, Brian D.

    2016-09-22

    The solar-to-hydrogen (STH) efficiency is calculated for various operating conditions for a two-step metal oxide solar thermochemical hydrogen production cycle using cerium(IV) oxide. An inert sweep gas was considered as the O2 removal method. Gas and solid heat recuperation effectiveness values were varied between 0 and 100% in order to determine the limits of the effect of these parameters. The temperature at which the inert gas is separated from oxygen for an open-loop and recycled system is varied. The hydrogen and water separation temperature was also varied and the effect on STH efficiency quantified. This study shows that gas heat recuperation is critical for high efficiency cycles, especially at conditions that require high steam and inert gas flowrates. A key area for future study is identified to be the development of ceramic heat exchangers for high temperature gas-gas heat exchange. Solid heat recuperation is more important at lower oxidation temperatures that favor temperature-swing redox processing, and the relative impact of this heat recuperation is muted if the heat can be used elsewhere in the system. A high separation temperature for the recycled inert gas has been shown to be beneficial, especially for cases of lower gas heat recuperation and increased inert gas flowrates. A higher water/hydrogen separation temperature is beneficial for most gas heat recuperation effectiveness values, though the overall impact on optimal system efficiency is relatively small for the values considered. © 2016 Hydrogen Energy Publications LLC.

  1. Evaluation of microscopic deformation behaviors of metal matrix composite by means of SFC test and acoustic emission (Part I :Effect of loading direction)

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Joon Hyun; Kang, Moon Phil [Pusan National University, Pusan (Korea, Republic of)

    1998-11-15

    Metal matrix composites(MMCs) offer significant increase in elastic modulus and strength as well as improve resistance to fatigue initiation, creep and wear. For the successful application of MMC to structure, it is very important to understand micro-failure mechanism of material. However, due to complex deformation behavior intrinsically of bulk composite panel, single fiber composite(SFC) has been successfully used to understand a fundamental mechanism of deformation in MMC. The substantial failure mechanisms of MMC were affected by many factors such as the loading direction, the heat treatment condition, matrix properties and volume fraction. In this study, the microscopic deformation behavior of MMC is investigated for single SiC fiber reinforced aluminium alloy under the different loading direction, that is, longitudinal and transverse loading. Acoustic emission(AE) technique has been also used to detect the signals corresponding to each microscopic deformation behavior under the loading. Special attention is given to AE characteristics associated with interfacial debonding between fiber and matrix under the different leading direction.

  2. Evaluation of microscopic deformation behaviors of metal matrix composite by means of SFC test and acoustic emission (Part I :Effect of heat treatment on IFSS)

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Joon Hyun; Kang, Moon Phil [Pusan National University, Pusan (Korea, Republic of)

    1998-11-15

    Metal matrix composites(MMCs) are rapidly becoming one of the strongest candidates for structural materials for high temperature application. It is well recognized that MMCs always experience at least one large cool-down from processing temperature before any significant applied service loading. Due to the large difference in thermal expansion coefficient between the fiber and matrix, large thermal residual stresses generally develop in composites. It was reported from many previous studies that the effects of thermal residual stress on mechanical properties and fracture behavior were much more complex and dramatic than conventional engineering materials. Therefore it is crucial to evaluate the effect of heat treatment which changes the characteristic of distribution of thermal residual stress in MMCs. Single fiber composite(SFC) test based on the balance in a micromechanical model is a quite convenient method to evaluate interfacial shear strength(IFSS) and the failure mode of composite. In this study the effect of heat treatment on IFSS and the microscopic failure mechanism of MMC is investigated by combining acoustic emission(AE) technique with fragmentation test. The characteristic of AE signal, IFSS and microscopic failure mechanism due to heat treatment condition is discussed.

  3. The electron-transfer based interaction between transition metal ions and photoluminescent graphene quantum dots (GQDs): a platform for metal ion sensing.

    Science.gov (United States)

    Huang, Hongduan; Liao, Lei; Xu, Xiao; Zou, Mingjian; Liu, Feng; Li, Na

    2013-12-15

    The electron-transfer based quenching effect of commonly encountered transition metal ions on the photoluminescence of grapheme quantum dots (GQDs) was for the first time investigated, and was found to be associated with electron configuration of the individual metal ion. Ethylene diamine tetraacetic acid (EDTA), the metal ion chelator, can competitively interact with metal ions to recover the quenched photoluminescence of GQDs. Basically, metal ions with empty or completely filled d orbits could not quench the photoluminescence of GQDs, but this quenching effect was observed for the metal ions with partly filled d orbits. Based on the quenching-recovering strategy, a simple optical metal sensing platform was established by taking Ni(2+) as an example. Using the nickel ion-specific chelating reagent, dimethylglyoxime (DMG), to replace EDTA, a detection limit of 4.1 μM was obtained in standard solution. This proposed strategy does not need further functionalization of GQDs, facilitating the application for simple, fast and cost-effective screening of metal ions.

  4. Redução e substituição do ácido crômico na etapa de condicionamento de ABS para metalização Reduction and replacement of chromic acid in step-conditioning of ABS for metallization

    Directory of Open Access Journals (Sweden)

    Ana Paula Kurek

    2009-01-01

    Full Text Available Na etapa de condicionamento de peças em acrilonitrila-butadieno-estireno (ABS, geralmente, são empregadas soluções sulfocrômicas, resultando na geração de efluentes altamente tóxicos e ambientalmente poluentes. Este trabalho apresenta resultados do estudo do emprego de soluções condicionantes visando à redução e substituição do ácido crômico. O condicionamento das amostras foi realizado em banhos contendo soluções de ácido crômico e ácido sulfúrico, permanganato de potássio e ácido fosfórico, e ácido sulfúrico, ácido fosfórico e dicromato de potássio, variando-se concentração, tempo de imersão e temperatura. A morfologia e estrutura da superfície das amostras foram analisadas por microscopia eletrônica de varredura (MEV, rugosidade e espectroscopia no infravermelho (FITR/ATR e a qualidade da adesão metálica após cromagem foi avaliada por inspeção visual, testes de adesão e de corrosão por exposição à névoa salina. Os resultados mostraram que o condicionamento químico ocasionou remoção dos componentes do ABS na superfície das amostras, provocando modificações como rugosidade e formação de poros, cavidades e reentrâncias, que influenciaram na adesão e foram dependentes da solução e das condições empregadas. O ácido crômico pode ser empregado em concentrações menores que a solução padrão (400 g.L-1 e soluções isentas deste foram eficientes na modificação da superfície e adesão metálica.In step-conditioning (etching of acrylonitrile-butadiene-styrene (ABS terpolymer, use is generally made of sulfuric/chromic acid solutions resulting in the generation of highly toxic, environmentally polluting waste. The present work reports the results of a study of reduction and replacement of chromic acid from the etching solution. The samples conditioning was carried out in baths containing solutions of chromic and sulfuric acids, potassium permanganate and phosphoric acid, and sulfuric

  5. Research of upper surface roughness of metal parts fabricated by selective laser melting%选区激光熔化成型金属零件上表面粗糙度的研究

    Institute of Scientific and Technical Information of China (English)

    刘睿诚; 杨永强; 王迪

    2013-01-01

    In order to provide the theory basis to improve the surface quality , the main factors affecting the upper surface roughness of metal parts fabricated by selective laser melting (SLM) were studied.By studying the single track melting, the upper surface roughness of SLM parts was analyzed from the view of melting track lapping .The metal parts were fabricated by using the self-developed fabrication equipment Dimetal-280 and the measure roughness parameters were compared with the theoretical value.The theoretical value of arithmetical mean deviation of the profile Ra was 3.21μm and the theoretical value of ten-point height of irregulartlies Rz was 12.79μm.The actual value was Ra =7.36μm and Rz =40.01μm.After electrochemical polishing, the surface roughness was reduced to Ra =2.34μm and Rz =10.86μm.The results prove that upper surface roughness of the metal part was influenced by melting track width , scanning space and layer thickness altogether.The reason of the discrepancy between theoretical value and actual value was some defects such as instability in melting track, spheroidization on the surface and dust adhesiveness .The quality of surface roughness was greatly improved after electrochemical polishing .The metal parts processed by selective laser melting could obtain satisfied surface roughness in this experiment .The results provide guidance to surface research and industrial application in the future.%  为了改善成型件表面质量,从微观上研究了决定选区激光熔化成型金属零件的上表面粗糙度的主要因素,通过研究单熔道成型,从熔道搭接的角度理论分析了成型件的上表面粗糙度,基于自主研发的成型设备Dimet-al-280加工实体零件进行了实际测量对比,获得表面粗糙度的轮廓算术平均偏差Ra 的理论值为3.21μm,微观不平度十点高度Rz 的理论值为12.79μm,其实测值Ra =7.36μm,Rz =40.01μm;进行喷砂和电解抛光处理后,

  6. Radiology of total hip replacement

    Energy Technology Data Exchange (ETDEWEB)

    Griffiths, H.J.; Lovelock, J.E.; McCollister Evarts, C.; Geyer, D.

    1984-06-01

    The radiology of total hip replacement (THR) and its complications is reviewed in conjunction with a long-term follow-up study on 402 patients with 501 prostheses. The indications, contraindications, biomechanics, and operative management of these patients is discussed. Clinical complications such as deep vein thrombosis, pulmonary embolism, and hemorrhage are mentioned. Postoperative infections including granulomatous pseudotumors, dislocations and fractures, true loosening of the prosthesis, and heterotopic bone formation (HBF) are discussed and illustrated. The importance of differentiating the lucent line from true loosening is stressed. Mechanical and other clinical complications which are largely ignored by radiologists are also discussed. The uses of arthrography and bone scanning are included.

  7. [Proximal and total femur replacement].

    Science.gov (United States)

    Pennekamp, P H; Wirtz, D C; Dürr, H R

    2012-07-01

    Reconstruction of segmental bone defects of the proximal femur following wide tumor resection or revision arthroplasty. Aggressive benign or primary malignant bone tumors of the proximal femur; destructive metastases; massive segmental bone defects of the proximal femur; periprosthetic fractures. Local infection; very short life expectancy (acetabular bone stock. Anterolateral approach. Exposure and detachment of the iliopsoas and gluteus medius muscle from the proximal femur with a sufficient safety margin to the bone; distal transsection of the vastus lateralis/intermedius and rectus femoris muscle according to the extraosseous tumor extension; distal femur osteotomy al least 3 cm beyond the farthest point of tumor extension; in case of total femur replacement, additional lateral arthrotomy of the knee with resection of the ligaments and menisci; reaming of the medullary canal after securing the shaft with a Verbrugge clamp; trial assembly and reduction followed by the definitive implantation of the prosthesis with adjustment of the femoral neck anteversion in 5° increments; soft tissue reconstruction and fixation to an attachment tube covering the prosthesis; in case of total femur replacement, the preparation of the tibia is followed by the coupling of the tibial and femoral components. Infection prophylaxis, 20 kg partial weight bearing, continuous passive motion. A total of 20  patients with proximal femur replacement and 2 patients with total femur replacement implanted between June 2007 and December 2011 were retrospectively reviewed. Three patients had primary malignant bone tumors, while 19 patients underwent resection for metastatic disease. The mean age at surgery was 62.0 ± 18.1 years (18-82 years). Fifteen patients with a mean follow-up of 20.3 ± 17.2 months (4-51 months) were studied. Among the 22 cases, periprosthetic infection occurred in 3 patients (13.6%), dislocation in 2 patients (9.1%). Evaluation of the functional

  8. MRI after patellofemoral replacement: The preserved compartments

    Energy Technology Data Exchange (ETDEWEB)

    Heyse, Thomas J., E-mail: heyse@med.uni-marburg.de [Department of Orthopedics and Rheumatology, University Hospital Marburg, Baldingerstrasse, 35043 Marburg (Germany); Figiel, Jens [Department of Radiology, University Hospital Marburg, Marburg (Germany); Hähnlein, Ulrike [Department of Orthopedics and Rheumatology, University Hospital Marburg, Baldingerstrasse, 35043 Marburg (Germany); Timmesfeld, Nina [Institute for Medical Biometry and Epidemiology, Marburg (Germany); Lakemeier, Stefan; Schofer, Markus D.; Fuchs-Winkelmann, Susanne; Efe, Turgay [Department of Orthopedics and Rheumatology, University Hospital Marburg, Baldingerstrasse, 35043 Marburg (Germany)

    2012-09-15

    Introduction: The aim of this study was to assess the reproducibility of magnet resonance imaging (MRI) analysis of preserved anatomic structures of the knee after patellofemoral replacement (PFR). It was hypothesized that evaluation of cartilage, ligaments, meniscus and tendons would result in high inter-observer reliability after PFR. Material and methods: MRI, tailored to reduce metallic artefacts of the knee, after PFR was performed in seven patients. Two independent investigators evaluated cartilage, menisci, collateral and cruciate ligaments, the quadriceps and patellar tendons and the presence of joint effusion. The reviewers used a five-point scale to give a degree of confidence to their evaluation of each parameter. Inter-observer reliability was determined by calculation of Cohen's Kappas. Results: Artefact provoked by the implants was not observed. For all assessed structures, there was excellent inter-observer reliability, with high Cohen's Kappas. There were also high levels of inter-observer agreement and observer confidence in the evaluation of cartilage, meniscus, tendons, ligaments and joint effusion. Conclusion: Tailored MRI allows reproducible analysis of the preserved knee joint structures after PFR. It might prove helpful in assessment of painful knee joints after PFR.

  9. B Plant process piping replacement feasibility study

    Energy Technology Data Exchange (ETDEWEB)

    Howden, G.F.

    1996-02-07

    Reports on the feasibility of replacing existing embedded process piping with new more corrosion resistant piping between cells and between cells and a hot pipe trench of a Hanford Site style canyon facility. Provides concepts for replacement piping installation, and use of robotics to replace the use of the canyon crane as the primary means of performing/supporting facility modifications (eg, cell lining, pipe replacement, equipment reinstallation) and operational maintenenace.

  10. REMINDER REPLACEMENT OF FRENCH CARDS

    CERN Multimedia

    Human Resources Division; Cards.Service@cern.ch

    2001-01-01

    The French Ministry of Foreign Affairs is currently replacing all diplomatic cards, special cards and employment permits («attestations de fonctions») held by members of the personnel and their families. These cards are replaced by secure, computerized equivalents. The old cards may no longer be used after 31 December 2001. For the purposes of the handover, members of the personnel must go personally to the cards office (33/1-015) between 8h30 and 12h30, in order to fill in a «fiche individuelle» form, taking the following documents for themselves and members of their families already in possession of a French card : A recent identity photograph in 4.5 cm x 3.5 cm format, the French card in their possession, an A4 photocopy of the same French card, certified by the cards office as being a true copy. Those members of the personnel whose cards (and/or cards belonging to members of their families) are shortly due to expire, or have recently done so, are also requested...

  11. Total hip replacement in dancers.

    Science.gov (United States)

    Buyls, Inge R A E; Rietveld, A B M Boni; Ourila, Tiia; Emerton, Mark E; Bird, H A

    2013-04-01

    A case report of a professional contemporary dancer who successfully returned to the stage after bilateral total hip replacements (THR) for osteoarthritis is presented, together with her own commentary and a retrospective cohort study of total hip replacements in dancers. In the presented cohort, there were no post-operative dislocations or infections, the original pain had been relieved, rehabilitation was objectively normal and all resumed their dance (teaching) activities. Nevertheless, they were disappointed about the prolonged rehabilitation. Due to their high demands as professional dancers, post-operative expectations were too optimistic in view of the usual quick and favourable results of THR in the older and less physically active, general population. In all dancers with unilateral osteoarthritis, the left hip was involved, which may reflect the tendency to use the left leg as standing leg and be suggestive that strenuous physical activity may lead to osteoarthritis. Better rehabilitation guidelines are needed for dancer patients undergoing THR, especially drawing their attention to realistic post-operative expectations.

  12. 23 CFR 650.411 - Procedures for bridge replacement and rehabilitation projects.

    Science.gov (United States)

    2010-04-01

    ... Rehabilitation Program § 650.411 Procedures for bridge replacement and rehabilitation projects. (a) Consideration... the State to the Secretary in accordance with 23 CFR part 630, subpart A Federal-Aid Programs... 23 Highways 1 2010-04-01 2010-04-01 false Procedures for bridge replacement and...

  13. 78 FR 67086 - Safety Zone, Submarine Cable Replacement Operations, Kent Island Narrows; Queen Anne's County, MD

    Science.gov (United States)

    2013-11-08

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone, Submarine Cable Replacement Operations... safety of mariners and their vessels on navigable waters during submarine cable replacement operations at... installation of a submarine cable within a federal navigation channel requiring divers, a barge, and...

  14. Modification of the Sheehan Knee arthroplasty for additional replacement of the femoropatellar articulation

    NARCIS (Netherlands)

    Miehlke, R.; Croon, H.W.

    1980-01-01

    An alternative version of the Sheehan knee arthroplasty is presented allowing additional replacement of the patellofemoral joint as there is a definite need for replacement of this part of the knee joint in osteoarthritis. However, the original Sheehan design which is considered to be one of the bes

  15. The world-class Howard's Pass SEDEX Zn-Pb district, Selwyn Basin, Yukon. Part II: the roles of thermochemical and bacterial sulfate reduction in metal fixation

    Science.gov (United States)

    Gadd, Michael G.; Layton-Matthews, Daniel; Peter, Jan M.; Paradis, Suzanne; Jonasson, Ian R.

    2017-03-01

    against this model. Indeed, the new data indicate that much of the base metal sulfide mineralization was emplaced below the sediment-water interface within sulfidic muds under reducing conditions during early diagenesis. Furthermore, thermochemical sulfate reduction provided most of the reduced sulfur within the Zn-Pb deposits.

  16. The world-class Howard's Pass SEDEX Zn-Pb district, Selwyn Basin, Yukon. Part II: the roles of thermochemical and bacterial sulfate reduction in metal fixation

    Science.gov (United States)

    Gadd, Michael G.; Layton-Matthews, Daniel; Peter, Jan M.; Paradis, Suzanne; Jonasson, Ian R.

    2016-07-01

    against this model. Indeed, the new data indicate that much of the base metal sulfide mineralization was emplaced below the sediment-water interface within sulfidic muds under reducing conditions during early diagenesis. Furthermore, thermochemical sulfate reduction provided most of the reduced sulfur within the Zn-Pb deposits.

  17. 金属零件选区激光熔化直接成型技术研究进展%Research Progress of Direct Manufacturing of Metal Parts by Selective Laser Melting

    Institute of Scientific and Technical Information of China (English)

    杨永强; 王迪; 吴伟辉

    2011-01-01

    随着快速成型技术的进步,其研究热点转变到快速直接制造会属功能零件方面,应用范围也拓展到航空航天、医疗、汽车、模具等领域.针对选区激光熔化(SLM)技术更适合精密小批量金属零件的快速制造等特点,结合华南理工大学在该技术方面的研究进展,研究讨论了成型材料、成型工艺与过程控制、应用及其影响因素等,并对SLM技术现状、存在问题和发展趋势进行了分析.%With the development of rapid prototyping (RP) technology, the research interests change to direct manufacturing of metal parts with functions.The application fields of RP are expanded to the areas of aerospace,medical, motor vehicle, mould, etc.According to the characteristics of selective laser melting (SLM) applicable for rapid manufacturing of fine-structured and small-lot metal parts, powder materials, process, control, applications and affect factors are studied and discussed by combining the research work of the author's group.The status-in-art,problems and developing prospect of SLM technology are also discussed.

  18. Proximal femoral replacement for the treatment of periprosthetic fractures.

    Science.gov (United States)

    Klein, Gregg R; Parvizi, Javad; Rapuri, Venkat; Wolf, Christopher F; Hozack, William J; Sharkey, Peter F; Purtill, James J

    2005-08-01

    A periprosthetic fracture around the femoral component is a rare but potentially problematic complication after total hip arthroplasty. Reconstruction can be challenging, especially when severe bone stock deficiency is encountered. Proximal femoral replacement is one method of treating the severely deficient proximal part of the femur. The present report describes the outcomes of revision total hip arthroplasty with use of a proximal femoral replacement in a cohort of patients who had a Vancouver type-B3 periprosthetic fracture. With use of a computerized institutional database, all patients in whom a Vancouver type-B3 fracture (characterized by severe proximal bone deficiency and a loose femoral stem) had been treated with a proximal femoral replacement were identified. A modular femoral replacement with proximal porous coating had been used in all cases. The twenty-one patients who were identified had had a mean age of 78.3 years (range, fifty-two to ninety years) at the time of the index operation. The clinical and radiographic records of these patients were reviewed. At the time of the latest follow-up (mean, 3.2 years), all but one of the patients were able to walk and had minimal to no pain. Complications included persistent wound drainage that was treated with incision and drainage (two hips), dislocation (two hips), refracture of the femur distal to the stem (one hip), and acetabular cage failure (one hip). Despite a relatively high complication rate, we believe that proximal femoral replacement is a viable option for the treatment of periprosthetic fractures in older patients with severe bone deficiency. If a proximal femoral replacement is used, the stability of the hip must be tested diligently intraoperatively and a constrained acetabular liner should be utilized if instability is encountered. In order to enhance the bone stock, the proximal part of the femur, however poor in quality, should be retained for reapproximation onto the implant.

  19. Metallated metal-organic frameworks

    Energy Technology Data Exchange (ETDEWEB)

    Bury, Wojciech; Farha, Omar K.; Hupp, Joseph T.; Mondloch, Joseph E.

    2017-08-22

    Porous metal-organic frameworks (MOFs) and metallated porous MOFs are provided. Also provided are methods of metallating porous MOFs using atomic layer deposition and methods of using the metallated MOFs as catalysts and in remediation applications.

  20. Metallated metal-organic frameworks

    Energy Technology Data Exchange (ETDEWEB)

    Bury, Wojciech; Farha, Omar K.; Hupp, Joseph T.; Mondloch, Joseph E.

    2017-02-07

    Porous metal-organic frameworks (MOFs) and metallated porous MOFs are provided. Also provided are methods of metallating porous MOFs using atomic layer deposition and methods of using the metallated MOFs as catalysts and in remediation applications.

  1. OPTIMUM ORDERING POLICY FOR PREVENTIVE AGE REPLACEMENT

    Institute of Scientific and Technical Information of China (English)

    Young T.PARK; Jing SUN

    2009-01-01

    Most of the spare ordering policies treated up to now have assumed that preventive and corrective replacement costs are equal, which implies in essential that there is no significant need for preventive replacement. This paper presents an ordering policy for preventive age replacement with minimal repair. Introducing the replacement, repair, inventory holding and shortage costs, the expected cost rate is derived. A procedure to determine jointly the ordering time for a spare and the preventive replacement time for the operating unit so as to minimize the expected cost rate is proposed. To explain the ordering policy and the optimization procedure, a numerical example is also included.

  2. ORO. The physical developer replacement?

    Science.gov (United States)

    Wood, Michael A; James, Tim

    2009-12-01

    In the process of fingerprint development Physical Developer has been largely the method of choice on porous surfaces after coming into contact with wet environments. It is only recently that a new technique has been identified which could replace this standard technique. This study aims to build on previous research and expand knowledge regarding the technique. The study built on previous research and compared Physical Developer to Oil Red O, testing both on four paper types, while being placed in three different water types and an accelerant for various amounts of time. Marks were placed with both heavily 'loaded' sebaceous fingers and 'normal' un-washed fingers. Results show that Oil Red O consistently produced clearer more detailed marks from the 'loaded' fingers, but neither technique proved to work better on the 'normal' marks. Neither technique developed any prints from the accelerant.

  3. Optimal randomized scheduling by replacement

    Energy Technology Data Exchange (ETDEWEB)

    Saias, I.

    1996-05-01

    In the replacement scheduling problem, a system is composed of n processors drawn from a pool of p. The processors can become faulty while in operation and faulty processors never recover. A report is issued whenever a fault occurs. This report states only the existence of a fault but does not indicate its location. Based on this report, the scheduler can reconfigure the system and choose another set of n processors. The system operates satisfactorily as long as, upon report of a fault, the scheduler chooses n non-faulty processors. We provide a randomized protocol maximizing the expected number of faults the system can sustain before the occurrence of a crash. The optimality of the protocol is established by considering a closely related dual optimization problem. The game-theoretic technical difficulties that we solve in this paper are very general and encountered whenever proving the optimality of a randomized algorithm in parallel and distributed computation.

  4. Controversies in hormone replacement therapy

    Directory of Open Access Journals (Sweden)

    A. Baziad

    2001-09-01

    Full Text Available Deficiency of estrogen hormone will result in either long-term or short-term health problems which may reduce the quality of life. There are numerous methods by which the quality of female life can be achieved. Since the problems occuring are due to the deficiency of estrogen hormone, the appropriate method to tackle the problem is by administration of estrogen hormone. The administration of hormone replacement therapy (HRT with estrogen may eliminate climacteric complaints, prevent osteoporosis, coronary heart disease, dementia, and colon cancer. Although HRT has a great deal of advantage, its use is still low and may result in controversies. These controversies are due to fact that both doctor and patient still hold on to the old, outmoded views which are not supported by numerous studies. Currently, the use of HRT is not only based on experience, or temporary observation, but more on evidence based medicine. (Med J Indones 2001; 10: 182-6Keywords: controversies, HRT

  5. Replacement reactor to revolutionise magnets

    CERN Document Server

    Atkins, G

    2002-01-01

    Electric motors, hearing aids and magnetic resonance imaging are only some of the applications that will benefit from the first advances in magnets in a quarter of a century. Magnets achieve their characteristics when electrons align themselves to produce a unified magnetic field. Neutrons can probe these magnetic structures. The focus is not just on making more powerful magnets, but also identifying the characteristics that make magnets cheaper and easier for industry to manufacture. Staff from the ANSTO's Neutron Scattering Group have already performed a number of studies on the properties of magnets using using HIFAR, but the Replacement Research Reactor that will produce cold neutrons would allow scientists to investigate the atomic properties of materials with large molecules. A suite of equipment will enable studies at different temperatures, pressures and magnetic fields

  6. Renal replacement therapy in Europe

    DEFF Research Database (Denmark)

    Noordzij, Marlies; Kramer, Anneke; Abad Diez, José M

    2014-01-01

    BACKGROUND: This article provides a summary of the 2011 ERA-EDTA Registry Annual Report (available at www.era-edta-reg.org). METHODS: Data on renal replacement therapy (RRT) for end-stage renal disease (ESRD) from national and regional renal registries in 30 countries in Europe and bordering the .......6-47.0], and on dialysis 39.3% (95% CI 39.2-39.4). The unadjusted 5-year patient survival after the first renal transplantation performed between 2002 and 2006 was 86.7% (95% CI 86.2-87.2) for kidneys from deceased donors and 94.3% (95% CI 93.6-95.0) for kidneys from living donors....

  7. Leptin replacement improves cognitive development.

    Directory of Open Access Journals (Sweden)

    Gilberto J Paz-Filho

    Full Text Available BACKGROUND: Leptin changes brain structure, neuron excitability and synaptic plasticity. It also regulates the development and function of feeding circuits. However, the effects of leptin on neurocognitive development are unknown. OBJECTIVE: To evaluate the effect of leptin on neurocognitive development. METHODOLOGY: A 5-year-old boy with a nonconservative missense leptin gene mutation (Cys-to-Thr in codon 105 was treated with recombinant methionyl human leptin (r-metHuLeptin at physiologic replacement doses of 0.03 mg/kg/day. Cognitive development was assessed using the Differential Ability Scales (DAS, a measure of general verbal and nonverbal functioning; and selected subtests from the NEPSY, a measure of neuropsychological functioning in children. PRINCIPAL FINDINGS: Prior to treatment, the patient was morbidly obese, hypertensive, dyslipidemic, and hyperinsulinemic. Baseline neurocognitive tests revealed slower than expected rates of development (developmental age lower than chronological age in a majority of the areas assessed. After two years, substantial increases in the rates of development in most neurocognitive domains were apparent, with some skills at or exceeding expectations based on chronological age. We also observed marked weight loss and resolution of hypertension, dyslipidemia and hyperinsulinemia. CONCLUSIONS: We concluded that replacement with r-metHuLeptin is associated with weight loss and changes in rates of development in many neurocognitive domains, which lends support to the hypothesis that, in addition to its role in metabolism, leptin may have a cognitive enhancing role in the developing central nervous system. TRIAL REGISTRATION: ClinicalTrials.gov NCT00659828.

  8. Bonding Elastomers To Metal Substrates

    Science.gov (United States)

    Dickerson, George E.; Kelley, Henry L.

    1990-01-01

    Improved, economical method for bonding elastomers to metals prevents failures caused by debonding. In new technique, vulcanization and curing occur simultaneously in specially designed mold that acts as form for desired shape of elastomer and as container that positions and supports metal parts. Increases interface adhesion between metal, adhesive, and elastomer.

  9. Development and first validation of a simplified CT-based classification system of soft tissue changes in large-head metal-on-metal total hip replacement: intra- and interrater reliability and association with revision rates in a uniform cohort of 664 arthroplasties

    Energy Technology Data Exchange (ETDEWEB)

    Boomsma, Martijn F.; Warringa, Niek [Isala Hospital, Department of Radiology, Zwolle (Netherlands); Edens, Mireille A. [Isala Hospital, Department of Innovation and Science, Zwolle (Netherlands); Lingen, Christiaan P. van; Ettema, Harmen B.; Verheyen, Cees C.P.M. [Isala Hospital, Department of Orthopaedics, Zwolle (Netherlands); Maas, Mario [AMC, Department of Radiology, Amsterdam (Netherlands)

    2015-08-15

    After implantation of a metal-on-metal total hip arthroplasty (MoM THA), a large incidence of pseudotumor formation has been described recently. Several centers have invited patients for follow-up in order to screen for pseudotumor formation. The spectrum of abnormalities found by CT in MoM THA patients can be unfamiliar to radiologists and orthopedic surgeons. Previously, a CT five-point grading scale has been published. In this paper, a simplification into a three-point classification system gives insight in the morphological distinction of abnormalities of the postoperative hip capsule in MoM implants in relation to the decision for revision. The reliability of this simplified classification regarding intra- and interrater reliability and its association with revision rate is investigated and discussed. All patients who underwent MoM THA in our hospital were invited for screening. Various clinical measures and CT scan were obtained in a cross-sectional fashion. A decision on revision surgery was made shortly after screening. CT scans were read in 582 patients, of which 82 patients were treated bilaterally. CT scans were independently single read by two board-certified radiologists and classified into categories I-V. In a second meeting, consensus was obtained. Categories were subsequently rubricated in class A (categories I and II), B (category III), and C (categories IV and V). Intra- and inter-radiologist agreement on MoM pathology was assessed by means of the weighted Cohen's kappa. Categorical data were presented as n (%), and tested by means of Fisher's exact test. Continuous data were presented as median (min-max) and tested by means of Mann-Whitney U test (two group comparison) or Kruskal-Wallis test (three group comparison). Logistic regression analysis was performed in order to study independence of CT class for association with revision surgery. Univariate statistically significant variables were entered in a multiple model. All statistical

  10. Inspection of Conductive Prosthetic Replacements using Electromagnetic Methods of Non-Destructive Testing

    Directory of Open Access Journals (Sweden)

    Tatiana Strapacova

    2008-01-01

    Full Text Available This paper describes the use of electromagnetic methods of non-destructive testing for detecting of inhomogeneities presence in a prosthetic replacement with focus on strut fractures in prosthetic heart valves. In the first part of this paper there are described a basic principle of eddy current testing, heart valve replacement and materials which are usually used for it. The experimental part contains description of simulated problem, obtained simulation results and their interpretation for use in medicine.

  11. Complications Related to Metal-on-Metal Articulation in Trapeziometacarpal Joint Total Joint Arthroplasty

    Directory of Open Access Journals (Sweden)

    Christina Frølich

    2015-05-01

    Full Text Available Adverse reactions to metal-on-metal (MoM prostheses are well known from total hip joint resurfacing arthroplasty with elevated serum chrome or cobalt, pain and pseudo tumor formation. It may, however, also be seen after total joint replacement of the trapeziometacarpal joint using MoM articulation, and we present two cases of failure of MoM prostheses due to elevated metal-serum levels in one case and pseudo tumor formation in another case. Furthermore, we suggest a diagnostic algorithm for joint pain after MoM trapeziometacarpal joint replacement based on published experiences from MoM hip prostheses and adverse reactions to metal.

  12. Materials characterization studies on LANA75/85 materials for replacement beds

    Energy Technology Data Exchange (ETDEWEB)

    Shanahan, Kirk L. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2016-12-30

    During FY15 and FY16, a purchase order (PO) was placed with Japan Metals and Chemicals, USA after an open bidding procurement process for 282 kg of LaNi4.25Al0.75 and 226 kg. of LaNi4.15Al0.85. These materials were to be used in Tritium Facility replacement beds for existing beds that have reached the end of their useful life. As part of the PO, a 100 g. sample of each material was delivered to the SRNL Hydrogen Processing Group for characterization studies as is typically done for all newly acquired hydride materials. The PO actually employed a “trust but verify” approach where JMCUSA was allowed to ship materials it felt met specifications without SRS confirmation, as long as the data used to do so was delivered to SRS as part of the PO documentation package. Subsequent SRNL analysis revealed that the material met all specifications and was of very high quality. This report documents those findings.

  13. Research on Construction Monitoring Techniques for Cable Replacement of the Cable-Stayed Bridge

    Directory of Open Access Journals (Sweden)

    Dai Pu

    2013-09-01

    Full Text Available Due to various reasons, some cable-stayed bridges require the replacement of part or all stay cables after operating for a period of time. In this study, based on some engineering practices of stay cable replacement, the condition of bridge structure before replacement is analyzed with Finite Element Analysis method for plane member system. The theoretical calculations, cable force measurement, replacement methods and process monitoring for cable replacement are introduced to find out the key technical problems. From the specified bridge monitoring practices, we suggest monitoring cable tension and the main beam alignment during the process of cable replacement, to make sure the cable-stayed bridge reaches its design conditions.

  14. Bringing Ceramic Parts to Earth

    Institute of Scientific and Technical Information of China (English)

    履之

    1995-01-01

    The benefits of using ceramic engine components are well known:They are tougher than metal parts, weigh less, and can withstand hotter operating temperatures.So why aren’t they being used now? High cost.

  15. Metals and alloys in the function of biomaterials

    Directory of Open Access Journals (Sweden)

    Dejan I. Tanikić

    2012-04-01

    Full Text Available Biomaterials are natural or synthetic materials, used for guidance, maintaining or replacing the function of the human body's live tissues. Metal biomaterials are mainly used for replacing broken or damaged hard tissues such as bones, because of their high strength, toughness and corrosion resistance. The most frequently used metals are stainless steels, cobalt based alloys as well as titanium and its alloys. A review of the metals and alloys mostly used in biomedicine are presented in this paper.

  16. 激光烧结工艺参数对Fe-16%Ni合金致密度的影响%Effect of process parameters on density of Fe-16%Ni metal part formed by selective laser melting

    Institute of Scientific and Technical Information of China (English)

    白培康; 李玉新; 刘斌

    2011-01-01

    采用激光烧结成形技术研究了不同工艺参数对Fe-16%Ni金属粉末选区激光烧结成型件微观结构和致密性的影响.结果表明,随着脉冲宽度、扫描速度和铺粉厚度的增加,烧结后试样的密度先增加然后减少,随着扫描间距的增加,烧结后试样的密度减小.当脉冲宽度0.7 ms,扫描速度1000mm/min,铺粉厚度0.15 mm,扫描间距0.15 mm时,烧结成型件成型质量较好.%Effect of process parameters on density and microstructure of sintered part of Fe-16% Ni metal powder fabricated by selective laser melting was studied. The results show the density of the sintered part firstly increases and then decreases with increasing of the scanning speed, laser pulse width, powder layer thickness and the density decreases with increasing of the scanning interval. Moreover, the sintered parts with the good forming quality are obtained when the laser pulse width, scanning speed, the powder layer thickness and the scanning interval are O.7 ms,1000 mm/min,0.15 mm and 0.15 mm,respectively.

  17. Rebitagem por fricção ("FricRiveting". Desenvolvimento de uma nova técnica de união para juntas híbridas do tipo polímero-metal. Parte I: processo e microestrutura Friction riveting (FricRiveting. Development of a new joining technique for polymer-metal hybrid joints. Part I: process and microstructure

    Directory of Open Access Journals (Sweden)

    Sergio T. Amancio-Filho

    2011-12-01

    Full Text Available A rebitagem por fricção (do Inglês "Friction Riveting" é uma nova técnica de união pontual desenvolvida para a fabricação de estruturas híbridas do tipo polímero-metal. Nesta técnica, um rebite metálico cilíndrico é usado para unir um ou mais componentes termoplásticos. O processo de união ocorre através da plastificação e forjamento da extremidade do rebite via calor friccional, oriundo da rotação e pressão axial do rebite em contato com os componentes a serem unidos. Vantagens dessa nova técnica de união são, entre outras, ciclos de união curtos associados com a ausência ou diminuição do tempo de preparação das superfícies dos componentes, ausência de emissões tóxicas, e simplicidade operacional. Juntas rebitadas por fricção apresentam elevada resistência mecânica. Nesse artigo a viabilidade da técnica foi demonstrada através de um estudo de caso em juntas de polieterimida com rebites de alumínio 2024-T351. Juntas com elevada resistência mecânica (com valores médios de até 93% da resistência à tração do rebite foram produzidas e caracterizadas em termos de microestrutura (microscopia ótica, de varredura e por microtomografia computadorizada.The Friction Riveting (FricRiveting technique is a new alternative spot joining process developed for polymer-metal hybrid structures. In the technique, a cylindrical metallic rivet is used to join one or more thermoplastic-metal components by means of plasticizing and deforming the tip of the rotating rivet through frictional heating. Advantages of this new technique are short joining cycles, minimal sample preparation, absence of environmental emissions and simple operability. Friction riveted joints have enhanced mechanical performance. This study demonstrates the feasibility of FricRiveting by analyzing a case-study joint on polyetherimide / aluminum alloys. Sound joints on polyetherimide/aluminum 2024-T351 with elevated mechanical strength (up to 93

  18. Electrodeposition of Pd based binary catalysts on Carbon paper via surface limited redox-replacement reaction for oxygen reduction reaction

    CSIR Research Space (South Africa)

    Modibedi, RM

    2014-05-01

    Full Text Available -replacement reaction (SLR3) with Cu as a sacrificial metal. Co-deposition of the two metals on carbon paper was also performed. ECALD is the appropriate fabrication methodology because the resultant catalysts showed good dispersion of the nanoclusters on the carbon...

  19. Gene replacement in Penicillium roqueforti.

    Science.gov (United States)

    Goarin, Anne; Silar, Philippe; Malagnac, Fabienne

    2015-05-01

    Most cheese-making filamentous fungi lack suitable molecular tools to improve their biotechnology potential. Penicillium roqueforti, a species of high industrial importance, would benefit from functional data yielded by molecular genetic approaches. This work provides the first example of gene replacement by homologous recombination in P. roqueforti, demonstrating that knockout experiments can be performed in this fungus. To do so, we improved the existing transformation method to integrate transgenes into P. roqueforti genome. In the meantime, we cloned the PrNiaD gene, which encodes a NADPH-dependent nitrate reductase that reduces nitrate to nitrite. Then, we performed a deletion of the PrNiaD gene from P. roqueforti strain AGO. The ΔPrNiaD mutant strain is more resistant to chlorate-containing medium than the wild-type strain, but did not grow on nitrate-containing medium. Because genomic data are now available, we believe that generating selective deletions of candidate genes will be a key step to open the way for a comprehensive exploration of gene function in P. roqueforti.

  20. VNR CMS Pixel detector replacement

    CERN Document Server

    2017-01-01

    Joel Butler, spokesperson of the CMS collaboration explains how a team from many different partner institutes installed a new detector in CMS. This detector is the silicon pixel detector and they’ve been working on it for about five years, to replace one of our existing detectors. This detectors measures particles closer to the beam than any of the other components of this huge detector behind me. It gives us the most precise picture of tracks as they come out of the collisions and expand and travel through the detector. This particular device has twice as many pixels, 120 million, as opposed to about 68 million in the old detector and it can take data faster and pump it out to the analysis more quickly. 00’53’’ Images of the descent, insertion and installation of first piece of the Pixel detector on Tue Feb 28. Images of the descent, insertion and installation of second piece of the Pixel and the two cylinders being joined.

  1. Orthogonal Matching Pursuit with Replacement

    CERN Document Server

    Jain, Prateek; Dhillon, Inderjit S

    2011-01-01

    In this paper, we consider the problem of compressed sensing where the goal is to recover almost all the sparse vectors using a small number of fixed linear measurements. For this problem, we propose a novel partial hard-thresholding operator that leads to a general family of iterative algorithms. While one extreme of the family yields well known hard thresholding algorithms like ITI (Iterative Thresholding with Inversion) and HTP (Hard Thresholding Pursuit), the other end of the spectrum leads to a novel algorithm that we call Orthogonal Matching Pursuit with Replacement (OMPR). OMPR, like the classic greedy algorithm OMP, adds exactly one coordinate to the support at each iteration, based on the correlation with the current residual. However, unlike OMP, OMPR also removes one coordinate from the support. This simple change allows us to prove that OMPR has the best known guarantees for sparse recovery in terms of the Restricted Isometry Property (a condition on the measurement matrix). In contrast, OMP is kn...

  2. Visual Image Sensor Organ Replacement

    Science.gov (United States)

    Maluf, David A.

    2014-01-01

    This innovation is a system that augments human vision through a technique called "Sensing Super-position" using a Visual Instrument Sensory Organ Replacement (VISOR) device. The VISOR device translates visual and other sensors (i.e., thermal) into sounds to enable very difficult sensing tasks. Three-dimensional spatial brightness and multi-spectral maps of a sensed image are processed using real-time image processing techniques (e.g. histogram normalization) and transformed into a two-dimensional map of an audio signal as a function of frequency and time. Because the human hearing system is capable of learning to process and interpret extremely complicated and rapidly changing auditory patterns, the translation of images into sounds reduces the risk of accidentally filtering out important clues. The VISOR device was developed to augment the current state-of-the-art head-mounted (helmet) display systems. It provides the ability to sense beyond the human visible light range, to increase human sensing resolution, to use wider angle visual perception, and to improve the ability to sense distances. It also allows compensation for movement by the human or changes in the scene being viewed.

  3. [Animal experiment, can we replace?

    Science.gov (United States)

    Combrisson, H

    2017-09-01

    Animal experiment is a subject of controversies. Some people, defenders of animals, think that it is not acceptable to use for scientific purposes at the risk of making them suffer or assert that the results obtained with animals are not transposable in the human beings. Others, in particular researchers in biology or medicine, think that the animal models are essential for the biomedical search. This confrontation of the opinions bases largely on an evolution of the place of animals in our society. The regulations authorize the use of animals for scientific purposes but oblige to make it under restrictive conditions. The application of 3Rs - replacement, reduction, and refinement - expressed in 1959 by Russel and Burch is an ethical guide to improve the welfare of animals in research. The alternative methods do not allow, in the present state of the knowledge, to answer all the scientific questions in biology and medicine research. They are, most of the time, complementary methods of the in vivo methods. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  4. Heavy Metal Fluoride Glasses.

    Science.gov (United States)

    1987-04-01

    i 2N E ihhhhh1112h MEmhhhhEEEohhhhE I.’....momo 111111111’-20 LA ’Ll2. AFWL-TR-86-37 AFWL-TR- 86-37 oT C ,l C ’-’ N HEAVY METAL FLUORIDE GLASSES 0nI...Secwrit CkasmfcationJ HEAVY METAL FLUORIDE GLASSES 12. PERSONAL AUTHOR(S) Reisfield, Renata; and Eyal, Mrek 13. TYPE OF REPORT 113b. TIME COVERED 114...glasses containing about 50 mole% of ZrF4 [which can be replaced by HfF 4 or TIF 4 (Refs. 1-3) or heavy metal fluorides based on PbF2 and on 3d-group

  5. A liquid metal-based structurally embedded vascular antenna: I. Concept and multiphysical modeling

    Science.gov (United States)

    Hartl, D. J.; Frank, G. J.; Huff, G. H.; Baur, J. W.

    2017-02-01

    This work proposes a new concept for a reconfigurable structurally embedded vascular antenna (SEVA). The work builds on ongoing research of structurally embedded microvascular systems in laminated structures for thermal transport and self-healing and on studies of non-toxic liquid metals for reconfigurable electronics. In the example design, liquid metal-filled channels in a laminated composite act as radiating elements for a high-power planar zig-zag wire log periodic dipole antenna. Flow of liquid metal through the channels is used to limit the temperature of the composite in which the antenna is embedded. A multiphysics engineering model of the transmitting antenna is formulated that couples the electromagnetic, fluid, thermal, and mechanical responses. In part 1 of this two-part work, it is shown that the liquid metal antenna is highly reconfigurable in terms of its electromagnetic response and that dissipated thermal energy generated during high power operation can be offset by the action of circulating or cyclically replacing the liquid metal such that heat is continuously removed from the system. In fact, the SEVA can potentially outperform traditional copper-based antennas in high-power operational configurations. The coupled engineering model is implemented in an automated framework and a design of experiment study is performed to quantify first-order design trade-offs in this multifunctional structure. More rigorous design optimization is addressed in part 2.

  6. Biology of tooth replacement in amniotes

    Institute of Scientific and Technical Information of China (English)

    John A Whitlock; Joy M Richman

    2013-01-01

    Tooth replacement is a common trait to most vertebrates, including mammals. Mammals, however, have lost the capacity for continuous tooth renewal seen in most other vertebrates, and typically have only 1–2 generations of teeth. Here, we review the mechanisms of tooth replacement in reptiles and mammals, and discuss in detail the current and historical theories on control of timing and pattern of tooth replacement and development.

  7. Licensing of the Australian replacement research reactor

    Energy Technology Data Exchange (ETDEWEB)

    Garea, Veronica B. [INVAP S.E., San Carlos de Bariloche (Argentina)

    2002-07-01

    The Australian Nuclear Science and Technology Organisation (ANSTO)'s Replacement Research Reactor has been submitted to a comprehensive licensing process of which peer review has been a fundamental part. Following Australian Regulation, an application for a site licence was the first step supported by an Environmental Impact Statement approved by The Minister for the Environment and Heritage, and a Reference Accident Analysis. After the site licence had been granted and the contract awarded to the Designer and Constructor, INVAP S.E:, a 2500 page Preliminary Safety Analysis Report was submitted by ANSTO to the Australian Radiation Protection and Nuclear Safety Agency (ARPANSA), which conducted its review. ARPANSA requested that the PSAR be also reviewed by an experts mission from the International Atomic Energy Agency. The PSAR was also reviewed by the Argentine Regulatory Body, it was submitted to public examination in Australia and it was reviewed by international experts hired as consultants by several Australian organisations. A public forum was also held in Sydney. The Regulator, the applicant and the Designer-Constructor maintained constant interaction during the whole process, so that questions, comments and observations that arose from the review of the PSAR were fed back to the designers. This process allowed for a robust, safe design enriched by the results of the safety analysis and review process. (author)

  8. Drug dosing during continuous renal replacement therapy.

    Science.gov (United States)

    Churchwell, Mariann D; Mueller, Bruce A

    2009-01-01

    Continuous renal replacement therapy (CRRT) has given clinicians an important option in the care of critically ill patients. The slow and continuous dialysate and ultrafiltrate flow rates that are employed with CRRT can yield drug clearances similar to an analogous glomerular filtration rate of the native kidneys. Advantages such as superior volume control, excellent metabolic control, and hemodynamic tolerance by critically ill patients are well documented, but an understanding of drug dosing for CRRT is still a bit of a mystery. Although some pharmaceutical companies have dedicated postmarket research in this direction, many pharmaceutical companies have chosen not to pursue this information as it is not mandated and represents a relatively small part of their market. This lack of valuable information has created many challenges in the care of the critically ill patient as intermittent hemodialysis drug dosing recommendations cannot be extrapolated to CRRT. This drug dosing review will highlight factors that clinicians should consider when determining a pharmacotherapy regimen for a patient receiving CRRT.

  9. Aortic valve replacement in octogenarians

    Directory of Open Access Journals (Sweden)

    Dark John H

    2007-07-01

    Full Text Available Abstract Background and Aims As our population ages and life expectancy increases the number of people aged over 80 and more referred for cardiac surgery is growing. This study sought to identify the outcome of aortic valve replacement (AVR in octogenarians. Methods 68 patients aged 80 years or more underwent AVR at the Freeman Hospital, between April 2001 and April 2004. A retrospective review of the notes and outcomes from the patients' GP and the NHS strategic tracking service was performed. 54% (37 underwent isolated AVR whilst 46% (31 underwent combined AVR and CABG. Results Follow up was 100% complete. The mean age was 83.1 ± s.d. 2.9 years, a mean gradient of 83 ± s.d. 31 mmHg and mean AVA of 0.56 cm2. The mean additive EuroSCORE was 8.6 ± s.d. 1.2, the logistic EuroSCORE mean 12.0 ± s.d. 5.9. In hospital 30 day mortality was 13 %. Survival was 80% at 1 year and 78% at 2 years. Median follow up was for 712 days. Stepwise logistic regression identified chronic obstructive airways disease as an independent predictor of mortality (p Conclusion Our study demonstrates that the operative mortality for AVR in the over eighties is good, whilst the mid to long term outcome is excellent There is a very low attrition rate with those undergoing the procedure living as long than their age matched population. This study confirms AVR is a safe, acceptable treatment for octogenarians with excellent mid term outcomes.

  10. Menopause and hormone replacement therapy

    Directory of Open Access Journals (Sweden)

    Ali Baziad

    2001-12-01

    Full Text Available The global population in the 21st century has reached 6.2 billion people, by the year 2025 it is to be around 8.3-8.5 billion, and will increase further. Elderly people are expected to grow rapidly than other groups. The fastest increase in the elderly population will take place in Asia. Life expectancy is increasing steadily throughout developed and developing countries. For many  menopausal women, increased life expectancy will accompanied by many health problems. The consequences of estrogen deficiency are the menopausal symptoms. The treatment of menopause related complaints and diseases became an  important socioeconomic and medical issue. Long term symptoms, such as the increase in osteoporosis fractures, cardio and cerebrovascular disesses and dementia, created a large financial burden on individuals and society. All these health problems can be lreated or prevented by hormone replacement therapy (HRT. Natural HRT is usually prefened. Synthetic  estrogen in oral contraceptives (oc are not recommended for HRT. Many contra-indications for oc, but now it is widely usedfor HRT. The main reasons for discontinuing HRT are unwanted bleeding, fear of cancer, and negative side effects. Until now there are sill debates about the rebrtonship between HRT and the incidence of breast cancer. Many data showed that there were no clear relationship between the use of HRT and breast cancer. ThereÎore, nwny experts advocate the use of HRTfrom the first sign of climacteric complaints until death. (Med J Indones 2001;10: 242-51Keywords: estrogen deficiency, climacteric phases, tibolone.

  11. Total joint replacement preadmission programs.

    Science.gov (United States)

    Messer, B

    1998-01-01

    Patients begin to formulate their expectations of the postoperative hospitalization during the preadmission program. The challenge is to better understand the factors patients consider when formulating judgments about the quality of preadmission education. For example, it may be that perceptions of the preadmission program are influenced by what patients believe about their postoperative pain and functional abilities. Specific attention needs to be given both preoperatively and postoperatively to instructing patients on realistic expectations for recovery. One other method of measuring patient outcomes is with the Health Status Profile (SF-36) (Response Healthcare Information Management, 1995). The SF-36 approach emphasizes the outcome of medical care as the patient sees it, in addition to a clinical evaluation of successful health care. This form is currently initiated in the physician's office and returned for scanning at the preadmission class. The patient then completes another SF-36 at 6 months and every year thereafter to compare measurable outcomes. Patients intending to have elective total joint replacements experience anxiety and require much support and education. An effective preadmission program is a major investment in a patient's recovery, as well as a unique marketing tool to customers. Preadmission programs can be viewed as an opportunity to enhance customer satisfaction. Preadmission clinics are an excellent means for nurses to improve the quality of patient care through patient education. the overall goal of preadmission testing programs is to ensure patient preparedness while increasing quality health care and overall customer satisfaction. To enhance program effectiveness, health care providers must lead collaborative efforts to improve the efficiency of systems.

  12. Sucrose-replacement by rebaudioside a in a model beverage.

    Science.gov (United States)

    Majchrzak, Dorota; Ipsen, Annika; Koenig, Juergen

    2015-09-01

    Rebaudioside A (RA), a component of Stevia rebaudiana, is a non-caloric sweetener of natural origin, suitable to meet consumers' demand for sweet taste, but undesirable flavors were reported at high concentrations. Aim of this study was to create a model beverage (ice-tea) in which sucrose was replaced increasingly by RA to identify optimal sensory profile for consumer acceptance. Samples with 20 % and 40 % sucrose replacement by RA, respectively, showed very similar sensory profiles but were significantly higher in some flavor attributes, such as artificial sweetness, licorice-like and metallic, as well as in sweet and bitter aftertaste (p < 0.05) compared to the reference ice-tea. In both hedonic tests, preference and acceptance samples with RA have been judged as comparable to the reference despite perception of some undesirable notes. In view of the results of our study it can be stated that a replacement of 20 % or 40 % sucrose by RA in an ice-tea is achievable.

  13. Arbuscular Mycorrhizal Fungi Can Benefit Heavy Metal Tolerance and Phytoremediation

    Science.gov (United States)

    Forgy, David

    2012-01-01

    Sites contaminated by heavy metals, such as industrial waste sites, create unwelcoming environments for plant growth. Heavy metals can have a wide range of toxic effects such as replacing essential elements or disrupting enzyme function. While some heavy metals are essential to plant nutrition at low concentrations, high concentrations of any…

  14. Arbuscular Mycorrhizal Fungi Can Benefit Heavy Metal Tolerance and Phytoremediation

    Science.gov (United States)

    Forgy, David

    2012-01-01

    Sites contaminated by heavy metals, such as industrial waste sites, create unwelcoming environments for plant growth. Heavy metals can have a wide range of toxic effects such as replacing essential elements or disrupting enzyme function. While some heavy metals are essential to plant nutrition at low concentrations, high concentrations of any…

  15. Research on precise forming process of aircraft aluminum large sheet metal part%飞机铝合金大型钣金件精确成形研究

    Institute of Scientific and Technical Information of China (English)

    白颖; 张引引; 赵刚; 陈磊

    2011-01-01

    Owing to the large size and low roughness, the forming process of large sheet metal parts of aircraft is difficult The shape and structure were optimized after increasing the corners and decreasing the length of adding straps based on the analysis of the part structure and assemble requirement The reasonable fabrication technology and a set of deformation-proof measures were defined using deep drawing method that improved the forming approach and the accuracy. By finite numerical simulation, theoretical computation and experiment, profile dimensions of the semi finished products were optimized, the reasonable tooling structure and the best BHP value were determined. Thus the precise forming requirement is satisfied.%飞机铝合金大型钣金件成形尺寸大,刚性差,制造难度大.通过对零件结构及装配要求的分析,提出了增大四周拐角角度,减少补加条带长度的改进意见,优化了零件的外形结构.借助双动拉深的优越性,采用了双动拉深的成形方法,确定出合理的制造流程和一套防止零件热处理产生变形的措施,提高了零件的成形准确度.利用有限元数值模拟、理论计算并结合实际试验,优化了展开毛坯的外形尺寸,确定出合理的工装结构以及压边力的最佳数值,达到零件精确成形的要求.

  16. The analysis method of deformation for laser cutting sheet metal part%激光切割钣金件时的工件变形分析方法

    Institute of Scientific and Technical Information of China (English)

    郭建; 兰天亮; 陈康

    2011-01-01

    利用ANSYS有限元分析软件建立了适合激光切割钣金件的三维实体模型,介绍了钣金件在自身重力和激光切割热源共同作用下,进行切割时工件变形大小的计算方法.将激光切剖热源简化为高斯热源,运用APDL语言分析计算了激光切剖时实际工件的变形大小.%ANSYS, finite element analysis software is used to establish a 3d entity model suited to the analysis of laser cutting sheet metal part.This paper introduces a method to detemine the size of workpiece deformation when it is cutted by laser under its own gravity and the action of the laser cutting heat source,and then simplifies the laser cutting heat source as the gauss heat source,analyzes and calculates the size of workpiece deformation when it is cutting by laser by writing APDL program

  17. Validación de un método de análisis para la determinación de metales pesados en partículas pM10 colectadas en aire ambiente

    Directory of Open Access Journals (Sweden)

    Jorge Herrera-Murillo

    2010-10-01

    Full Text Available Se validó un método de análisis para la determinación del contenido de metales presentes en partículas PM10 colectadas del aire ambiente de la ciudad de San José.Las muestras se tomaron utilizando dos muestreadores de aire de alto volumen con controlador de flujo, sobre filtros de cuarzo (20,3 cm x 25,4 cm, con un flujo promedio de 1,13 m3min-1 durante 24 h en dos sitios de la ciudad capital: Catedral Metropolitana y Junta de Educación de San José.  Para la determinación se utilizó espectrofotometría de absorción atómica con horno de grafito.Al analizar las muestras colectadas se determinó que las especies metálicas más abundantes son: Al, Fe y Mn; sin embargo solamente el Pb y Cu presentan factores de enriquecimiento importantes debido al posible aporte de actividades antropogénicas en la ciudad.

  18. The Process Design of Heavy Trucks Non-metallic Parts Coating Shop%重型卡车非金属件涂装车间工艺设计

    Institute of Scientific and Technical Information of China (English)

    张亚伦

    2012-01-01

    本文以新建重型卡车非金属件涂装线为例,详细介绍了非金属件面漆涂装的工艺流程、涂装工艺设备、辅助设备及物流方向,以及在线体空间极其有限的情况下需要考虑的主要因素,通过对主要因素的优化组合,得出了最佳工艺设计方案。%Nonmetal paint painting process, coating process equipment and auxiliary equipment, logistics direction and the main factors need to consider at the space extremely limited conditions were introduced in detail in this paper by using the new heavy trucks non-metal parts coating line as an example, the best process design was got by optimum combination of main factors.

  19. Transcatheter Aortic Valve Replacement in Europe

    DEFF Research Database (Denmark)

    Mylotte, Darren; Osnabrugge, Ruben L J; Windecker, Stephan;

    2013-01-01

    The authors sought to examine the adoption of transcatheter aortic valve replacement (TAVR) in Western Europe and investigate factors that may influence the heterogeneous use of this therapy.......The authors sought to examine the adoption of transcatheter aortic valve replacement (TAVR) in Western Europe and investigate factors that may influence the heterogeneous use of this therapy....

  20. Aortic valve replacement with the Nicks annulus enlargement procedure 12 years after mitral valve replacement.

    Science.gov (United States)

    Kazama, S; Kurata, A; Yamashita, Y

    1999-10-01

    An aortic valve replacement was successfully performed employing the Nicks annulus enlargement procedure in a case of aortic valve stenosis with small annulus 12 years after mitral valve replacement. Previous mitral valve replacement does not preclude feasibility of the Nicks procedure.

  1. [Extracorporeal renal replacement therapies in acute renal failure].

    Science.gov (United States)

    Schaefer, R M; Barenbrock, M; Teschner, M; Bahner, U

    2000-05-15

    The most serious forms of acute renal failure (ARF) are nowadays encountered in the intensive care unit (ICU), where up to 25% of new patients are reported to develop ARF. Lethality rates may reach 50 to 90% when the ARF is part of a multiple organ dysfunction syndrome. A multitude of extracorporeal procedures have been introduced into intensive care medicine. Applied with adequate skills and experience, most of these techniques will suffice to replace excretory renal function. However, because of low efficacy arterio-venous procedures (CAVH and CAVHD) have been abandoned for the veno-venous, pump-driven techniques (CVVH and CVVHD). Up to now, there is no consensus whether continuous or intermittent renal replacement therapy is more advantageous. In many cases, oliguric patients with circulatory instability will be treated by CVVH, even though there is no prospective study to show that in terms of outcome continuous treatment is superior to intermittent hemodialysis. It is equally conceivable to treat such patients with daily, prolonged (intermittent) hemodialysis. Apparently, the dose of replacement therapy, be it continuous filtration (36 to 48 l/24 h) or intermittent hemodialysis (daily 3 to 4 h) with a target BUN of less than 50 mg/dl, is more important than the modality of treatment. Moreover, there is good evidence that the use of biocompatible membranes (no complement- or leukocyte activation) is preferable and that with high-volume hemofiltration bicarbonate-containing replacement fluids should be used. However, despite all the technical advances, we firmly believe that the skills and the experience of those physicians and nurses who actually perform renal replacement therapy in the ICU are more important than the modality of treatment applied.

  2. The welfare implications of using exotic tortoises as ecological replacements.

    Directory of Open Access Journals (Sweden)

    Christine J Griffiths

    Full Text Available BACKGROUND: Ecological replacement involves the introduction of non-native species to habitats beyond their historical range, a factor identified as increasing the risk of failure for translocations. Yet the effectiveness and success of ecological replacement rely in part on the ability of translocatees to adapt, survive and potentially reproduce in a novel environment. We discuss the welfare aspects of translocating captive-reared non-native tortoises, Aldabrachelys gigantea and Astrochelys radiata, to two offshore Mauritian islands, and the costs and success of the projects to date. METHODOLOGY/PRINCIPAL FINDINGS: Because tortoises are long-lived, late-maturing reptiles, we assessed the progress of the translocation by monitoring the survival, health, growth, and breeding by the founders. Between 2000 and 2011, a total of 26 A. gigantea were introduced to Ile aux Aigrettes, and in 2007 twelve sexually immature A. gigantea and twelve male A. radiata were introduced to Round Island, Mauritius. Annual mortality rates were low, with most animals either maintaining or gaining weight. A minimum of 529 hatchlings were produced on Ile aux Aigrettes in 11 years; there was no potential for breeding on Round Island. Project costs were low. We attribute the success of these introductions to the tortoises' generalist diet, habitat requirements, and innate behaviour. CONCLUSIONS/SIGNIFICANCE: Feasibility analyses for ecological replacement and assisted colonisation projects should consider the candidate species' welfare during translocation and in its recipient environment. Our study provides a useful model for how this should be done. In addition to serving as ecological replacements for extinct Mauritian tortoises, we found that releasing small numbers of captive-reared A. gigantea and A. radiata is cost-effective and successful in the short term. The ability to release small numbers of animals is a particularly important attribute for ecological

  3. Lasershot(sm) marking system: high-volume labeling for safety-critical parts

    Energy Technology Data Exchange (ETDEWEB)

    Dane, C B; Hackel, L; Honig, J; Halpin, J; Chen, H-L; Mendieta, F; Harris, F; Lane, L; Daly, J; Harrison, J

    2001-02-16

    The Lasershot Marking System uses laser pulses to safely and permanently impress identification markings on metal components. This process does not remove material or change surface chemistry and actually increases the marked area's resistance to fatigue and corrosion failure. Lasershot marking is ideally suited for marking parts used in situations where safety is critical--from hip-joint replacements to commercial airliner components. The minimum size of the mark is limited only by the resolution of the reading system, allowing manufacturers to mark parts which, up to now, have been too small to label with mechanical peening techniques. The high resolution of the Lasershot marks makes them difficult to reproduce, providing a solution to the ongoing problem of inferior, counterfeited parts. The high marking rate of up to six marks per second makes this system practical and cost-effective for marking high-volume components.

  4. Single Tooth Replacement Using InCeram Resin Bonded Fixed Partial Denture: A Clinical Report.

    Directory of Open Access Journals (Sweden)

    Elnaz Moslehifard

    2014-02-01

    Full Text Available This clinical report describes a treatment option for replacement of a missing mandibular anterior tooth using InCeram resin bonded fixed partial denture (RBFPD. The conventional approach for replacing mandibular incisors dictates the placement of either a conventional porcelain-fused-to-metal (PFM bridge, Maryland bridge, or fiber-reinforced composite veneer bridge and several appearance-related disadvantages have been reported in the use of a prosthesis that incorporates a metal substructure. The InCeram bridge is a minimally invasive restoration and eliminates undesirable incisal graying frequently observed in metal RBFPDs. This method was successfully clinically applied to overcome shortcomings of other approaches that may require a minimal invasive technique to preserve lasting sound tooth structure.

  5. Surface imaging of metallic material fractures using optical coherence tomography.

    Science.gov (United States)

    Hutiu, Gheorghe; Duma, Virgil-Florin; Demian, Dorin; Bradu, Adrian; Podoleanu, Adrian Gh

    2014-09-10

    We demonstrate the capability of optical coherence tomography (OCT) to perform topography of metallic surfaces after being subjected to ductile or brittle fracturing. Two steel samples, OL 37 and OL 52, and an antifriction Sn-Sb-Cu alloy were analyzed. Using an in-house-built swept source OCT system, height profiles were generated for the surfaces of the two samples. Based on such profiles, it can be concluded that the first two samples were subjected to ductile fracture, while the third one was subjected to brittle fracture. The OCT potential for assessing the surface state of materials after fracture was evaluated by comparing OCT images with images generated using an established method for such investigations, scanning electron microscopy (SEM). Analysis of cause of fracture is essential in response to damage of machinery parts during various accidents. Currently the analysis is performed using SEM, on samples removed from the metallic parts, while OCT would allow in situ imaging using mobile units. To the best of our knowledge, this is the first time that the OCT capability to replace SEM has been demonstrated. SEM is a more costly and time-consuming method to use in the investigation of surfaces of microstructures of metallic materials.

  6. Alternative materials to improve total hip replacement tribology.

    Science.gov (United States)

    Santavirta, Seppo; Böhler, Max; Harris, William H; Konttinen, Yrjö T; Lappalainen, Reijo; Muratoglu, Orhun; Rieker, Claude; Salzer, Martin

    2003-08-01

    An improvement in tribology of bearing surfaces is an effective means of increasing the longevity of total hip replacement (THR). Currently, 3 approaches are available to achieve this aim: first, use of highly cross-linked UHMWPE; second, aluminum oxide ceramic bearings, and third, metal-on-metal bearings. Cross-linking reduces the wear resistance of UHMWPE markedly without impairment of other significant properties of the material. Simulator studies and some clinical long-term (10-22 years) follow-up surveys suggest an almost immeasurable wear of the highly cross-linked UHMWPE-based acetabular components during an expected clinical life span. Bioinert alumina ceramic (aluminum oxide) was introduced 3 decades ago for THR-bearing surfaces to improve performance and longevity. Alumina ceramic is entirely biostable and bioinert and has good mechanical properties. For correctly positioned alumina-on-alumina bearings, the annual linear wear rate has been reported to be 3.9 microm. Alumina heads have been successfully used in combination with polyethylene sockets, but as regards wear, the best results have been obtained with alumina-on-alumina bearings. In ceramic THR bearings, precise manufacture and contact surface geometry, including optimal clearance, are most important. For the currently available products, the component fracture risk is almost nonexistent (less than 1 per 1000). Metal-on-metal bearings were used in the early stage of THR surgery, although not all old designs were successful. More recent analyses of the early series have shown the advantages of metal-on-metal to be better and have led to a renaissance of this articulation. Initially, stainless steel was used because it was easy to manufacture and polish. Current metal-on-metal bearings are based on cobalt-chromium-molybdenum alloys with varying carbon contents. Such bearings are self-polishing. Linear wear rates remain at the level of a few microm a year. An improvement in technology has increased

  7. Complications Related to Metal-on-Metal Articulation in Trapeziometacarpal Joint Total Joint Arthroplasty

    DEFF Research Database (Denmark)

    Frølich, Christina; Hansen, Torben Bæk

    2015-01-01

    Adverse reactions to metal-on-metal (MoM) prostheses are well known from total hip joint resurfacing arthroplasty with elevated serum chrome or cobalt, pain and pseudo tumor formation. It may, however, also be seen after total joint replacement of the trapeziometacarpal joint using MoM articulation......, and we present two cases of failure of MoM prostheses due to elevated metal-serum levels in one case and pseudo tumor formation in another case. Furthermore, we suggest a diagnostic algorithm for joint pain after MoM trapeziometacarpal joint replacement based on published experiences from MoM hip...

  8. Conceptual Design Plan SM-43 Replacement Project

    Energy Technology Data Exchange (ETDEWEB)

    University of California, Los Alamos National Laboratory, SCC Project Office

    2000-11-01

    The Los Alamos National Laboratory Conceptual Design Plan for the SM-43 Replacement Project outlines plans for replacing the SM-43 Administration Building. Topics include the reasons that replacement is considered a necessity; the roles of the various project sponsors; and descriptions of the proposed site and facilities. Also covered in this proposal is preliminary information on the project schedule, cost estimates, acquisition strategy, risk assessment, NEPA strategy, safety strategy, and safeguards and security. Spreadsheets provide further detail on space requirements, project schedules, and cost estimates.

  9. Percutaneous tricuspid valve replacement in childhood

    Directory of Open Access Journals (Sweden)

    Mathias Emmel

    2015-01-01

    Full Text Available Percutaneous replacement of the tricuspid valve with a bovine jugular venous valve (melody valve was successfully undertaken in a 9-year-old boy. The patient had a previous history of bacterial endocarditis of the native tricuspid valve in infancy. Initially, a pericardial patch valve was created, followed by surgical replacement of the valve using a biological tissue valve at 4 years of age. Progressive stenosis and regurgitation of the biological valve, with severe venous congestion and resulting hepatic dysfunction prompted percutaneous valve replacement.

  10. Electro-deposition of Pd on carbon paper and Ni foam via surface limited redox-replacement reaction for oxygen reduction reaction

    CSIR Research Space (South Africa)

    Modibedi, RM

    2014-05-01

    Full Text Available Pd nanostructured catalysts were electrodeposited by surface-limited redox replacement reactions usingthe electrochemical atomic layer deposition technique. Carbon paper and Ni foam were used as substratesfor the electrodeposition of the metal...

  11. Determination of Metal Elements in Different Parts of Papaya by Flame Atomic Absorption Spectrometry with Microwave Digestion%微波消解-FAAS测定番木瓜不同部位的金属元素含量

    Institute of Scientific and Technical Information of China (English)

    袁竹连

    2013-01-01

    In order to explore the contents of metal elements in the papaya pulp,peel and seed, flame atomic absorption spectrometry (FAAS) method was used for determination of K,Na,Ca, Mg,Cu,Fe and Zn in the three parts of papaya. In addition, the digesting conditions were optimized. The results showed that under the optimized microwave digestion conditions and FAAS method, the samples were digested quickly and completely, there was a good linear relation between the concentration of the metal element standards and the absorbance value,the correlation coefficient was 0. 995 7 — 0. 999 9, the detection limit was 0. 002 — 0. 131, the recovery rate was 98. 30% —101. 67% and RSD was 0. 20%-4. 12%(n = 6). So microwave digestion-FAAS was a fast good detection method with complete digestion,less interference and stable measurement results. There were more K,Ca,Mg and less Cu,Fe,Zn in the three parts of papaya; there were more K,Mg,Cu,Zn,Fe in papaya peel and seed than in pulp,so papaya peel and seed had more advantage of development in food and medicine.%为探讨番木瓜果肉、果皮、瓜籽中金属元素的含量,采用微波消解-FAAS法测定了番木瓜3个部位的K、Na、Ca、Mg、Cu、Fe、Zn共7种金属元素的含量,并对微波消解条件进行了优化.结果显示,在优化的微波消解条件下,样品消解完全、速度快、效果好,FAAS测定的各金属元素质量浓度与吸光度均呈良好的线性关系,相关系数r为0.995 7~0.999 9,检出限为0.002~0.131,回收率为98.30%~101.67%,RSD为0.20%~4.12%(n=6),说明测定方法可靠,结果稳定;番木瓜3个部位均含有较高的K、Ca、Mg,但Cu、Fe、Zn含量均较低,与番木瓜果肉相比,番木瓜果皮和瓜籽中K、Mg、Cu、Zn、Fe含量较高,食品和药品开发优势更突出.

  12. Future trends in metal forming—equipment, materials and processes in automotive applications

    Science.gov (United States)

    Hitz, D.; Duggirala, R.

    1995-10-01

    Global competition in the automotive market has made a significant impact in the materials, processes, tools, and equipment used to make components. Steels are being replaced by other materials, such as aluminum, composites, and plastics, that meet the demand for a higher performance per weight ratio. From a processing viewpoint, the customers demand production of parts to near-net shape with little or no machining. Competition in business depends on understanding the needs of the customer in the coming years in the area of metal forming. A workshop was conducted using a novel approach to address the above issue. This presentation describes the approach and the results of the study.

  13. Our Experience with Short Stem Hip Replacement Surgery

    Directory of Open Access Journals (Sweden)

    Sumeet Rastogi

    2016-07-01

    Full Text Available Context- A short anatomical metaphyseal femoral stem is a desirable hip implant for bone and soft tissue preserving hip replacing surgery in young arthritic patients. Physiological loading of the proximal femur prevents stress shielding and preserves bone stock of the femur in the long run. Thus it is an ideal hip implant suited for conservative hip surgeries in active young adults with arthritic hips. Materials and methods- 50 Proxima hip replacements were performed on 41 patients with a mean age of 45 over a 3-year period (between July 2006 and September 2009. Diagnosis of hip pathologies varied from osteoarthritis secondary to avascular necrosis, rheumatoid arthritis, post-tubercular arthritis to dysplastic hips. 9 of these patients had symptomatic bilateral hip involvement and underwent bilateral hip replacement in a single sitting. All patient had a Proxima metaphyseal stem implantation( DePuy, Warsaw with either a large diameter metal on metal or pinnacle articulation. Clinical and radiological evaluation was done at 3 months, 6 months, 1 year and then yearly thereafter. Statiscal analysis used- VAS and Harris hip score formed the basis of evaluation Results- These patients were followed up for a mean period of 49 months (Range 36-72 months. The average incision size was 14.38 cm (10-18 cm and blood loss was 269 ml (175-450 ml. There was no peri-operative mortality or serious morbidity in any patients. One patient had an intraoperative lateral cortex crack that required only delayed rehabilitation. Five of the 41 patients (12.1 % had complications with three recovering completely and one requiring revision of femoral stem for aseptic loosening. One patient was lost in follow-up. Harris hip score improved from 52 to 89.3 at last follow-up. Overall 95.1% (39/41 patients had an excellent outcome at last follow-up. Conclusion- We conclude that Proxima metaphyseal stem provided clinically and radiologically stable fixation through snug fit

  14. Metal-on-Metal Hip Arthroplasty: A Review of Adverse Reactions and Patient Management

    Directory of Open Access Journals (Sweden)

    James Drummond

    2015-06-01

    Full Text Available Recent alarming joint registry data highlighting increased revision rates has prompted further research into the area of metal-on-metal hip replacements and resurfacings. This review article examines the latest literature on the topic of adverse reactions to metal debris and summarises the most up-to-date guidelines on patient management. Adverse reactions to metal debris can cause significant damage to soft tissue and bone if not diagnosed early. Furthermore, not every patient with an adverse reaction to metal debris will be symptomatic. As such, clinicians must remain vigilant when assessing and investigating these patients in order to detect failing implants and initiate appropriate management.

  15. Trials and Tribulations with VH Replacement

    Directory of Open Access Journals (Sweden)

    Wenzhao eMeng

    2014-01-01

    Full Text Available VH replacement is a type of antibody gene rearrangement in which an upstream heavy chain variable gene segment (VH invades a pre-existing rearrangement (VDJ. In this Hypothesis and Theory article, we begin by reviewing the mechanism of VH replacement, its developmental timing and its potential biological consequences. Then we explore the hypothesis that specific sequence motifs called footprints reflect VH replacement vs. other processes. We provide a compilation of footprint sequences from different regions of the antibody heavy chain, include data from the literature and from a high throughput sequencing experiment to evaluate the significance of footprint sequences. We conclude by discussing the difficulties of attributing footprints to VH replacement.

  16. Gyrator-type circuits replace ungrounded inductors

    Science.gov (United States)

    Deboo, G. J.

    1968-01-01

    Gyrator circuits using only transistors, capacitors, and resistors which can replace both grounded and ungrounded inductors have been developed to permit complete microminiaturization of circuitry by integration of the components.

  17. Total ankle replacement. Design evolution and results.

    Science.gov (United States)

    van den Heuvel, Alexander; Van Bouwel, Saskia; Dereymaeker, Greta

    2010-04-01

    The ankle joint has unique anatomical, biomechanical and cartilaginous structural characteristics that allow the joint to withstand the very high mechanical stresses and strains over years. Any minor changes to any of these features predispose the joint to osteoarthritis. Total ankle replacement (TAR) is evolving as an alternative to ankle arthrodesis for the treatment of end-stage ankle osteoarthritis. Initial implant designs from the early 1970s had unacceptably high failure and complication rates. As a result many orthopaedic surgeons have restricted the use of TAR in favour of ankle arthrodesis. Long term follow-up studies following ankle arthrodesis show risks of developing adjacent joint osteoarthritis. Therefore research towards a successful ankle replacement continues. Newer designs and longer-term outcome studies have renewed the interest in ankle joint replacement. We present an overview of the evolution, results and current concepts of total ankle replacement.

  18. Minimally Invasive Transcatheter Aortic Valve Replacement (TAVR)

    Medline Plus

    Full Text Available Watch a Broward Health surgeon perform a minimally invasive Transcatheter Aortic Valve Replacement (TAVR) Click Here to view the BroadcastMed, Inc. Privacy Policy and Legal Notice © 2017 BroadcastMed, Inc. ...

  19. Total ankle replacement - surgical treatment and rehabilitation.

    Science.gov (United States)

    Prusinowska, Agnieszka; Krogulec, Zbigniew; Turski, Piotr; Przepiórski, Emil; Małdyk, Paweł; Księżopolska-Orłowska, Krystyna

    2015-01-01

    Functions of the ankle joint are closely connected with the gait and ability to maintain an upright position. Degenerative lesions of the joint directly contribute to postural disorders and greatly restrict propulsion of the foot, thus leading to abnormal gait. Development of total ankle replacement is connected with the use of the method as an efficient treatment of joint injuries and continuation of achievements in hip and knee surgery. The total ankle replacement technique was introduced as an alternative to arthrodesis, i.e. surgical fixation, which made it possible to preserve joint mobility and to improve gait. Total ankle replacement is indicated in post-traumatic degenerative joint disease and joint destruction secondary to rheumatoid arthritis. In this paper, total ankle replacement and various types of currently used endoprostheses are discussed. The authors also describe principles of early postoperative rehabilitation as well as rehabilitation in the outpatient setting.

  20. 47 CFR 13.17 - Replacement license.

    Science.gov (United States)

    2010-10-01

    ... Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL COMMERCIAL RADIO OPERATORS General § 13.17 Replacement... Operator License, Marine Radio Operator Permit, First Class Radiotelegraph Operator's Certificate, Second... Radio Operator's License, Restricted GMDSS Radio Operator License, GMDSS Radio Maintainer's License,...

  1. Renal replacement therapy for acute renal failure.

    Science.gov (United States)

    Macedo, E; Bouchard, J; Mehta, R L

    2009-09-01

    Renal replacement therapy became a common clinical tool to treat patients with severe acute kidney injury (AKI) since the 1960s. During this time dialytic options have expanded considerably; biocompatible membranes, bicarbonate dialysate and dialysis machines with volumetric ultrafiltration control have improved the treatment for acute kidney injury. Along with advances in methods of intermittent hemodialysis, continuous renal replacement therapies have gained widespread acceptance in the treatment of dialysis-requiring AKI. However, many of the fundamental aspects of the renal replacement treatment such as indication, timing of dialytic intervention, and choice of dialysis modality are still controversial and may influence AKI patient's outcomes. This review outlines current concepts in the use of dialysis techniques for AKI and suggests an approach for selecting the optimal method of renal replacement therapy.

  2. Minimally Invasive Transcatheter Aortic Valve Replacement (TAVR)

    Medline Plus

    Full Text Available Watch a Broward Health surgeon perform a minimally invasive Transcatheter Aortic Valve Replacement (TAVR) Click Here to view the BroadcastMed, Inc. Privacy Policy and Legal Notice © 2017 BroadcastMed, Inc. ...

  3. Bone Marrow Transplantation (BMT) and Gene Replacement ...

    African Journals Online (AJOL)

    Bone Marrow Transplantation (BMT) and Gene Replacement Therapy (GRT) In Sickle Cell Anemia. ... manifesting clinical disease, while the heterozygoste(AS) are clinically ... medicine, we argue here the case for Bone marrow transplantation

  4. Metalworking. A Bilingual Text = Trabajo en Metal. Un Texto Bilingue.

    Science.gov (United States)

    Los Angeles Unified School District, CA. Div. of Career and Continuing Education.

    This booklet is a course of instruction in metal working in a two-column, English-Spanish format. Following an introduction to metal working and a lesson on safety, the booklet contains 17 units organized in 2 parts. Part 1, bench metal work, covers metals, processes, and tools; cutting; filling; drilling; grinding; bending and shaping; threading;…

  5. Metalworking. A Bilingual Text = Trabajo en Metal. Un Texto Bilingue.

    Science.gov (United States)

    Los Angeles Unified School District, CA. Div. of Career and Continuing Education.

    This booklet is a course of instruction in metal working in a two-column, English-Spanish format. Following an introduction to metal working and a lesson on safety, the booklet contains 17 units organized in 2 parts. Part 1, bench metal work, covers metals, processes, and tools; cutting; filling; drilling; grinding; bending and shaping; threading;…

  6. Carbonate replacement of lacustrine gypsum deposits in two Neogene continental basins, eastern Spain

    Science.gov (United States)

    Anadón, P.; Rosell, L.; Talbot, M. R.

    1992-07-01

    Bedded nonmarine gypsum deposits in the Miocene Teruel and Cabriel basins, eastern Spain, are partly replaced by carbonate. The Libros gypsum (Teruel Graben) is associated with fossiliferous carbonate wackestones and finely laminated, organic matter-rich mudstones which accumulated under anoxic conditions in a meromictic, permanent lake. The gypsum is locally pseudomorphed by aragonite or, less commonly, replaced by calcite. Low δ 13C values indicate that sulphate replacement resulted from bacterial sulphate reduction processes that were favoured by anacrobic conditions and abundant labile organic matter in the sediments. Petrographic evidence and oxygen isotopic composition suggest that gypsum replacement by aragonite occurred soon after deposition. A subsequent return to oxidising conditions caused some aragonite to be replaced by diagenetic gypsum. Native sulphur is associated with some of these secondary gypsum occurrences. The Los Ruices sulphate deposits (Cabriel Basin) contain beds of clastic and selenitic gypsum which are associated with limestones and red beds indicating accumulation in a shallow lake. Calcite is the principal replacement mineral. Bacterial sulphate reduction was insignificant in this basin because of a scarcity of organic matter. Stable isotope composition of diagenetic carbonate indicates that gypsum replacement occurred at shallow burial depths due to contact with dilute groundwaters of meteoric origin. Depositional environment evidently has a major influence upon the diagenetic history of primary sulphate deposits. The quantity of preserved organic matter degradable by sulphate-reducing bacteria is of particular importance and, along with groundwater composition, is the main factor controlling the mechanism of gypsum replacement by carbonate.

  7. Infective endocarditis following percutaneous pulmonary valve replacement

    DEFF Research Database (Denmark)

    Cheung, Gary; Vejlstrup, Niels; Ihlemann, Nikolaj;

    2013-01-01

    Infective endocarditis (IE) following percutaneous pulmonary valve replacement (PPVR) with the Melody valve is rarely reported. Furthermore, there are challenges in this diagnosis; especially echocardiographic evidence of vegetation within the prosthesis may be difficult.......Infective endocarditis (IE) following percutaneous pulmonary valve replacement (PPVR) with the Melody valve is rarely reported. Furthermore, there are challenges in this diagnosis; especially echocardiographic evidence of vegetation within the prosthesis may be difficult....

  8. Vertical dipole above a dielectric or metallic half-space - energy flow considerations

    CERN Document Server

    Berman, P R; Khitrova, G

    2014-01-01

    The emission pattern from a classical dipole located above and oriented perpendicular to a metallic or dielectric half space is calculated for a dipole driven at constant amplitude. This is a problem considered originally by Sommerfeld and analyzed subsequently by numerous authors. In contrast to most previous treatments, however, we focus on the energy flow in the metal or dielectric. It is shown that the radial Poynting vector in the metal points inwards when the frequency of the dipole is below the surface plasmon resonance frequency. In this case, energy actually flows of the interface at small radii. The Joule heating in the metal is also calculated and it is shown explicitly that Poynting's theorem holds for a cylindrical surface in the metal. When the metal is replaced by a dielectric having permittivity less than that of the medium in which the dipole is immersed, it is found that energy flows out of the interface for sufficiently large radii. In all cases it is assumed that the imaginary part of the ...

  9. [Replacement of tracheo-esophageal Provox prosthesis].

    Science.gov (United States)

    Biacabe, B; Laccourreye, O; Ménard, M; Hans, S; Brasnu, D

    2000-02-01

    To compare anesthesic techniques used between 1992 and 1997 at Laënnec Hospital for replacement by tracheo-esophageal Provox prosthesis: local and general anesthesia. Theoretical financial cost for replacement was estimated according to anaesthetic techniques. Provox in situ lifetime was calculated in 58 patients who underwent 115 and 49 replacements under general and local anaesthesia respectively. Age, sex, surgical and radiotherapy backgrounds, complications and anaesthetic techniques were studied as potential factors correlated with Provox in situ lifetime. Theoretical financial cost for replacement was estimated according to anaesthetic techniques. In 1992, 12% of Provox prosthesis were inserted under local anaesthesia and 54% in 1997. Provox in situ lifetime was either not influenced by anaesthetic techniques or other factors under analysis. The theoretical financial cost was estimated at 14, 341 FFrs and 6,048 FFrs for replacement under general and local anaesthesia respectively. Due to increased control of health care costs, we advocated local anaesthesia for Provox prosthesis replacement if control endoscopy is not required.

  10. Strategic vehicle fleet management - the replacement problem

    Directory of Open Access Journals (Sweden)

    Adam Redmer

    2016-03-01

    Full Text Available Background: Fleets constitute the most important production means in transportation. Their appropriate management is crucial for all companies having transportation duties. The paper is the third one of a series of three papers that the author dedicates to the strategic vehicle fleet management topic. Material and methods: The paper discusses ways of building replacement strategies for companies' fleets of vehicles. It means deciding for how long to exploit particular vehicles in a fleet (the fleet replacement problem - FR. The essence of this problem lies in the minimization of vehicle / fleet exploitation costs by balancing ownership and utilization costs and taking into account budget limitations. In the paper an original mathematical model (an optimization method allowing for the FR analysis is proposed. Results: An application of the proposed optimization method in a real-life decision situation (the case study within the Polish environment and the obtained solution are presented. The solution shows that there exist optimal exploitation periods of particular vehicles in a fleet. However, combination of them gives a replacement plan for an entire fleet violating budget constraints. But it is possible to adjust individual age to replacement of particular vehicles to fulfill budget constraints without losing economical optimality of a developed replacement plan for an entire fleet. Conclusions: The paper is the last one of a series of three papers that the author dedicated to the strategic vehicle fleet management topic including the following managerial decision problems: MAKE-or-BUY, sizing / composition and replacement.

  11. Microfocus study of metal distribution and speciation in tissue extracted from revised metal on metal hip implants

    Energy Technology Data Exchange (ETDEWEB)

    Hart, Alister J [Department of Orthopaedic Surgery, Imperial College and Imperial College Healthcare NHS Trust, Charing Cross Hospital Campus, Fulham Palace Rd, London W6 8RF (United Kingdom); Sandison, Ann [Department of Histopathology, Imperial College and Imperial College Healthcare NHS Trust, Charing Cross Hospital Campus, Fulham Palace Rd, London W6 8RF (United Kingdom); Quinn, Paul; Mosselmans, J Frederick W [Science Division, Diamond Light Source, Harwell Science and Innovation Campus, Didcot, Oxon, OX11 0DE (United Kingdom); Sampson, Barry [Department of Clinical Biochemistry, Imperial College and Imperial College Healthcare NHS Trust, Charing Cross Hospital Campus, Fulham Palace Rd, London W6 8RF (United Kingdom); Atkinson, Kirk D [8 Nuclear Department Defence Academy College of Management and Technology HMS Sultan Military Road Gosport PO12 3BY (United Kingdom); Skinner, John A [Department of Orthopaedics, Royal National Orthopaedic Hospital, HA7 4LP (United Kingdom); Goode, Angela [Dept of Materials, Imperial College London, SW7 2AZ (United Kingdom); Powell, Jonathan J, E-mail: Paul.Quinn@diamond.ac.u [Medical Research Council Human Nutrition Research Centre, Cambridge CB1 9NL (United Kingdom)

    2009-11-15

    Unexplained tissue inflammation in metal-on-metal hip replacements is suspected to be caused by implant-derived nanoparticles. The aim of this study was to investigate the nature of the metal particles in tissue surrounding metal-on-metal (MOM) hips that has been extracted during revision. Mapping of tissue surrounding the failed MOM hips was performed using microfocus X-ray Fluorescence (XRF). This revealed mainly Cr which was localized to the cellular regions. There was co-localisation of Co, were present, to areas of high Cr abundance. XANES of the tissue and appropriate standards revealed that the most common species were Cr(III) and Co(II). EXAFS analysis of the tissue and various metal standards revealed that the most abundant implant-related species was Cr(III) phosphate. Different tissue preparation methods, including frozen sectioning, were examined but were found not to affect the distribution or speciation of the metals in the tissue.

  12. Effect of Replacing Sugar with Non-Caloric Sweeteners in Beverages on the Reward Value after Repeated Exposure

    NARCIS (Netherlands)

    Griffioen-Roose, S.; Smeets, P.A.M.; Weijzen, P.L.G.; Rijn, van I.; Bosch, van den I.; Graaf, de C.

    2013-01-01

    Background: The reward value of food is partly dependent on learned associations. It is not yet known whether replacing sugar with non-caloric sweeteners in food is affecting long-term acceptance. Objective: To determine the effect of replacing sugar with non-caloric sweeteners in a nutrient-empty d

  13. Characterisation and treatment of roads covered with zinc ashes, muffle furnace fragments and lead slags from former non-ferrous metal industries in Belgium.

    Science.gov (United States)

    Vandecasteele, C; Van den Broeck, K; Van Gerven, T; Dutré, V; Seuntjens, P; Berghmans, P; Cornelis, C; Nouwen, J

    2002-08-01

    Zinc ashes, muffle furnace fragments and lead slags from non-ferrous industries were applied to pave roads in the North of Belgium. From an inventory it appeared that there are at least 490 km of such roads. In our survey the materials on these roads were characterised. The total metal concentration, the availability and the leaching as a function of time were determined. It appeared that these materials contain high concentrations of heavy metals, some of which are readily available. The high leaching of some metals makes them as such unsuitable as secondary construction material. Methods for the application of these materials for road construction were examined where the materials replaced part of the sand and gravel fraction in lean concrete and in bituminous mixtures, or where they replaced the sand in sand-cement mixtures, all these to be used for road foundations, cycle tracks, etc. When lead slags were applied in lean concrete, a material was obtained complying with the standards for secondary construction materials and with sufficient compressive strength for road foundations. When zinc ashes or muffle fragments were used to replace sand in sand-cement mixtures, again a suitable construction material was obtained. The other combinations tried out were rather unsuccessful, because of high metal leaching and/or poor compressive strength.

  14. Use of lanthanides to alleviate the effects of metal ion-deficiency in Desmodesmus quadricauda (Sphaeropleales, Chlorophyta.

    Directory of Open Access Journals (Sweden)

    Franz eGoecke

    2015-01-01

    Full Text Available Lanthanides are biologically non-essential elements with wide applications in technology and industry. Their concentration as environmental contaminants is, therefore, increasing. Although non-essential, lanthanides have been proposed (and even used to produce beneficial effects in plants, even though their mechanisms of action are unclear. Recently, it was suggested that they may replace essential elements. We tested the effect of low concentrations of lanthanides on the common freshwater microalga Desmodesmus quadricauda, grown under conditions of metal ion-deficiency (lower calcium or manganese concentrations. Our goal was to test if lanthanides can replace essential metals in their functions. Physiological stress was recorded by studying growth and photosynthetic activity using a pulse amplitude modulation (PAM fluorimeter. We found that nutrient stress reduced parameters of growth and chlorophyll fluorescence, such as maximal quantum yield, relative electron transport rate, photon capturing efficiency and light saturation irradiance. After adding low concentrations of five lanthanides, we confirmed that they can produce a stimulatory effect on microalgae, depending on the nutrient (metal deprivation. In the case of a calcium deficit, the addition of lanthanides partly alleviated the effects, probably by a partial substitution of the element. In contrast, with manganese deprivation (and at even lower concentrations, lanthanides enhanced the toxic effect and severely inhibited growth. These results show that lanthanides can replace essential elements, but their effects on microalgae depend on stress and the physiological state of the microalgae, raising the possibility of environmental impacts at even low concentrations.

  15. Use of lanthanides to alleviate the effects of metal ion-deficiency in Desmodesmus quadricauda (Sphaeropleales, Chlorophyta).

    Science.gov (United States)

    Goecke, Franz; Jerez, Celia G; Zachleder, Vilém; Figueroa, Félix L; Bišová, Kateřina; Řezanka, Tomáš; Vítová, Milada

    2015-01-01

    Lanthanides are biologically non-essential elements with wide applications in technology and industry. Their concentration as environmental contaminants is, therefore, increasing. Although non-essential, lanthanides have been proposed (and even used) to produce beneficial effects in plants, even though their mechanisms of action are unclear. Recently, it was suggested that they may replace essential elements. We tested the effect of low concentrations of lanthanides on the common freshwater microalga Desmodesmus quadricauda, grown under conditions of metal ion-deficiency (lower calcium or manganese concentrations). Our goal was to test if lanthanides can replace essential metals in their functions. Physiological stress was recorded by studying growth and photosynthetic activity using a pulse amplitude modulation (PAM) fluorimeter. We found that nutrient stress reduced parameters of growth and photosynthesis, such as maximal quantum yield, relative electron transport rate, photon capturing efficiency and light saturation irradiance. After adding low concentrations of five lanthanides, we confirmed that they can produce a stimulatory effect on microalgae, depending on the nutrient (metal) deprivation. In the case of a calcium deficit, the addition of lanthanides partly alleviated the adverse effects, probably by a partial substitution of the element. In contrast, with manganese deprivation (and at even lower concentrations), lanthanides enhanced the deleterious effect on cellular growth and photosynthetic competence. These results show that lanthanides can replace essential elements, but their effects on microalgae depend on stress and the nutritional state of the microalgae, raising the possibility of environmental impacts at even low concentrations.

  16. Use of lanthanides to alleviate the effects of metal ion-deficiency in Desmodesmus quadricauda (Sphaeropleales, Chlorophyta)

    Science.gov (United States)

    Goecke, Franz; Jerez, Celia G.; Zachleder, Vilém; Figueroa, Félix L.; Bišová, Kateřina; Řezanka, Tomáš; Vítová, Milada

    2015-01-01

    Lanthanides are biologically non-essential elements with wide applications in technology and industry. Their concentration as environmental contaminants is, therefore, increasing. Although non-essential, lanthanides have been proposed (and even used) to produce beneficial effects in plants, even though their mechanisms of action are unclear. Recently, it was suggested that they may replace essential elements. We tested the effect of low concentrations of lanthanides on the common freshwater microalga Desmodesmus quadricauda, grown under conditions of metal ion-deficiency (lower calcium or manganese concentrations). Our goal was to test if lanthanides can replace essential metals in their functions. Physiological stress was recorded by studying growth and photosynthetic activity using a pulse amplitude modulation (PAM) fluorimeter. We found that nutrient stress reduced parameters of growth and photosynthesis, such as maximal quantum yield, relative electron transport rate, photon capturing efficiency and light saturation irradiance. After adding low concentrations of five lanthanides, we confirmed that they can produce a stimulatory effect on microalgae, depending on the nutrient (metal) deprivation. In the case of a calcium deficit, the addition of lanthanides partly alleviated the adverse effects, probably by a partial substitution of the element. In contrast, with manganese deprivation (and at even lower concentrations), lanthanides enhanced the deleterious effect on cellular growth and photosynthetic competence. These results show that lanthanides can replace essential elements, but their effects on microalgae depend on stress and the nutritional state of the microalgae, raising the possibility of environmental impacts at even low concentrations. PMID:25674079

  17. Coronal Partings

    CERN Document Server

    Nikulin, Igor F

    2015-01-01

    The basic observational properties of the 'coronal partings'--the special type of the coronal magnetic structures, identified by a comparison of the coronal X-ray images and solar magnetograms--are considered. They represent channels inside the unipolar large-scale magnetic fields, formed by the rows of magnetic arcs directed to the neighboring fields of opposite polarity. The most important characteristics of the partings are revealed. It is found that--from the evolutionary and spatial point of view--the partings can transform to the coronal holes and visa versa. The classes of global, intersecting, and complex partings are identified.

  18. Vascular access for extracorporeal renal replacement therapy in veterinary patients.

    Science.gov (United States)

    Chalhoub, Serge; Langston, Cathy E; Poeppel, Karen

    2011-01-01

    Vascular access is the first and most basic requirement for successful extracorporeal renal replacement therapy (ERRT). Dual-lumen catheters are the most commonly used method of vascular access for ERRT in veterinary patients. An adequately functioning dialysis catheter allows for smooth and efficient patient management, whereas a poorly functioning catheter frustrates the technician, doctor, and patient. These catheters are fairly quick to place but require meticulous care for optimal function. The most common complications are thrombosis and infection. Monitoring catheter performance should be a routine part of dialysis patient care.

  19. Integrable RCS as a Proposed Replacement for Fermilab Booster

    Energy Technology Data Exchange (ETDEWEB)

    Eldred, Jeffrey [Fermilab; Valishev, Alexander [Fermilab

    2017-03-07

    Integrable optics is an innovation in particle accelerator design that potentially enables a greater betatron tune spread and damps collective instabilities. An integrable rapid-cycling synchrotron (RCS) would be an effective replacement for the Fermilab Booster, as part of a plan to reach multi-MW beam power at 120 GeV for the Fermilab high-energy neutrino program. We provide an example integrable lattice with features of a modern RCS - dispersion-free drifts, low momentum compaction factor, superperiodicity, chromaticity correction, bounded beta functions, and separate-function magnets.

  20. Metal Additive Manufacturing: A Review of Mechanical Properties (Postprint)

    Science.gov (United States)

    2016-04-21

    Metal additive manufacturing processes Direct metal laser sintering (DMLS), EOS Selective laser melting...6Al-4V AM tensile properties. Abbreviations: DMD, direct metal deposition; DMLS, direct metal laser sintering ; EBM, electron beam melting; HT, heat...100:1405–13 56. Khaing MW, Fuh JYH, Lu L. 2001. Direct metal laser sintering for rapid tooling: processing and characterisation of EOS parts. J.