WorldWideScience

Sample records for agarose mold compliance

  1. Mold

    Centers for Disease Control (CDC) Podcasts

    2011-05-02

    This podcast answers a listener's question about the risks associated with mold after a natural disaster or severe weather.  Created: 5/2/2011 by National Center for Environmental Health (NCEH).   Date Released: 5/2/2011.

  2. Recovering DNA from agarose gels.

    Science.gov (United States)

    Hegen, P N

    1994-09-01

    Methods and reagents is a unique monthly column that highlights current discussions in the newsgroup bionet.molbio.methds-reagnts, available on the internet. A commonly occurring theme on the net is the recovery of DNA, and this month's column discusses the pros and cons of various methods used to extract DNA fragments directly from agarose gels. For details on how to partake in the newsgroup, see the accompanying box. PMID:7985233

  3. The relationship of agarose gel structure to the sieving of spheres during agarose gel electrophoresis.

    OpenAIRE

    Griess, G A; Guiseley, K B; Serwer, P

    1993-01-01

    To understand the organization of fibers in an agarose gel, digitized electron micrographs are used here to determine the frequency distribution of interfiber distance (2Pc) in thin sections of agarose gels. For a preparation of underivatized agarose, a 1.5% gel has a Pc distribution that is indistinguishable from the Pc distribution of a computer-generated, random-fiber gel; the log of the occurrence frequency (F) decreases linearly as a function of Pc. As the agarose concentration decreases...

  4. Allergies, asthma, and molds

    Science.gov (United States)

    Reactive airway - mold; Bronchial asthma - mold; Triggers - mold; Allergic rhinitis - pollen ... Things that make allergies or asthma worse are called triggers. Mold is a common trigger. When your asthma or allergies become worse due to mold, you are ...

  5. Molds in the Environment

    Science.gov (United States)

    ... You Can Control Mold Program in Brief Related Issues Resources Quick Links Air Pollution & Respiratory Health Air Quality Asthma Mold What's ... in the Environment What are molds? What are some of the ...

  6. Rapid drug susceptibility test of Mycobacterium tuberculosis using microscopic time-lapse imaging in an agarose matrix.

    Science.gov (United States)

    Choi, Jungil; Yoo, Jungheon; Kim, Ki-Jung; Kim, Eun-Geun; Park, Kyung Ock; Kim, Hyejin; Kim, Haeun; Jung, Hyunju; Kim, Taeyoung; Choi, Myungjin; Kim, Hee Chan; Ryoo, Sungweon; Jung, Yong-Gyun; Kwon, Sunghoon

    2016-03-01

    Tuberculosis (TB) is a major global health problem, and multi-drug-resistant TB (MDR-TB) and extensively drug-resistant TB (XDR-TB) are spreading throughout the world. However, conventional drug susceptibility test (DST) methods, which rely on the detection of the colony formation on a solid medium, require 1-2 months to the result. A rapid and accurate DST is necessary to identify patients with drug-resistant TB and treat them with appropriate drugs. Here, we used microscopic imaging of Mycobacterium tuberculosis (MTB) immobilized in an agarose matrix for a rapid DST. The agarose matrix, which was molded in a microfluidic chip, was inoculated with MTB, and TB drugs in liquid culture medium diffused throughout the agarose to reach the MTB immobilized in the agarose matrix. After the responses of MTB to drugs were tracked with an automated microscopic system, an image-processing program automatically determined the susceptibility and resistance of MTB to specific doses of TB drugs. The automatic DST system was able to assess the drug susceptibility of various drug-resistant clinical TB strains within 9 days with an accuracy comparable to that of conventional method. Our rapid DST method based on microscopic time-lapse imaging greatly reduces the time required for a DST and can be used to rapidly and accurately treat TB patients. PMID:26754815

  7. Composition of agarose substrate affects behavioral output of Drosophila larvae

    Directory of Open Access Journals (Sweden)

    Anthi Aristomenis Apostolopoulou

    2014-01-01

    Full Text Available In the last decade the Drosophila larva has evolved into a simple model organism offering the opportunity to integrate molecular genetics with systems neuroscience. This led to a detailed understanding of the functional neuronal networks for a number of sensory functions and behaviors including olfaction, vision, gustation and learning and memory. Typically, behavioral assays in use exploit simple Petri dish setups with either agarose or agar as a substrate. However, neither the quality nor the concentration of the substrate is generally standardized across these experiments and there is no data available on how larval behavior is affected by such different substrates. Here, we have investigated the effects of different agarose concentrations on several larval behaviors. We demonstrate that agarose concentration is an important parameter, which affects all behaviors tested: preference, feeding, learning and locomotion. Larvae can discriminate between different agarose concentrations, they feed differently on them, they can learn to associate an agarose concentration with an odor stimulus and crawl faster on a substrate of higher agarose concentration. Additionally, we have investigated the effect of agarose concentration on three quinine based behaviors: preference, feeding and learning. We show that in all cases examined the behavioral output changes in an agarose concentration-dependent manner. Our results suggest that comparisons between experiments performed on substrates differing in agarose concentration should be done with caution. It should be taken into consideration that the agarose concentration can affect the behavioral output and thereby the experimental outcomes per se potentially due to an increased escape response on more rigid substrates.

  8. Bleach Neutralizes Mold Allergens

    Science.gov (United States)

    Science Teacher, 2005

    2005-01-01

    Researchers at National Jewish Medical and Research Center have demonstrated that dilute bleach not only kills common household mold, but may also neutralize the mold allergens that cause most mold-related health complaints. The study, published in the Journal of Allergy and Clinical Immunology, is the first to test the effect on allergic…

  9. Uptake and Recovery of Lead by Agarose Gel Polymers

    Directory of Open Access Journals (Sweden)

    Anurag Pandey

    2009-01-01

    Full Text Available Problem statement: The uptake and recovery of lead ions were investigated by using agarose gel polymers. Approach: The experimental results showed that the agarose gel were effective in removing Pb (II from solution. Biosorption equilibrium was approached within 4 h. Pseudo second-order was applicable to all the sorption data over the entire time range. Results: The sorption data conformed well to both the Langmuir and the Freundlich isotherm model. The maximum adsorption capacity (qmax onto agarose gel was 115 mg g-1 for Pb (II. The maximum uptake of metal ions was obtained at pH 2.0. At temperature 35°C, the biosorption of metal ions was found to be highest, with increase or decrease in temperature resulted in a decrease in the metal ions uptake capacity. Conclusion: Elution experiments were carried out to remove Pb (II ions from loaded agarose gel and the bound metal ions could be eluted successfully using 0.1 M EDTA solution. The results suggest that agarose gel can be used as a biosorbent for an efficient removal of Pb(II ions from aqueous solution.

  10. Preparation and Characterization of Chitosan—Agarose Composite Films

    Directory of Open Access Journals (Sweden)

    Zhang Hu

    2016-09-01

    Full Text Available Nowadays, there is a growing interest to develop biodegradable functional composite materials for food packaging and biomedicine applications from renewable sources. Some composite films were prepared by the casting method using chitosan (CS and agarose (AG in different mass ratios. The composite films were analyzed for physical-chemical-mechanical properties including tensile strength (TS, elongation-at-break (EB, water vapor transmission rate (WVTR, swelling ratio, Fourier-transform infrared spectroscopy, and morphology observations. The antibacterial properties of the composite films were also evaluated. The obtained results reveal that an addition of AG in varied proportions to a CS solution leads to an enhancement of the composite film’s tensile strength, elongation-at-break, and water vapor transmission rate. The composite film with an agarose mass concentration of 60% was of the highest water uptake capacity. These improvements can be explained by the chemical structures of the new composite films, which contain hydrogen bonding interactions between the chitosan and agarose as shown by Fourier-transform infrared spectroscopy (FTIR analysis and the micro-pore structures as observed with optical microscopes and scanning electron microscopy (SEM. The antibacterial results demonstrated that the films with agarose mass concentrations ranging from 0% to 60% possessed antibacterial properties. These results indicate that these composite films, especially the composite film with an agarose mass concentration of 60%, exhibit excellent potential to be used in food packaging and biomedical materials.

  11. Recovery of uranium by tannin immobilized on agarose

    International Nuclear Information System (INIS)

    Tannin, which is a ubiquitous and inexpensive material, was immobilized on agarose gel to produce an excellent adsorbent for uranium recovery from seawater. Optimal conditions for the immobilization of tannin on agarose gel by both the epichlorohydrin and cyanuric chloride coupling procedures were examined in detail. The resulting immobilized tannin has a highly selective ability to adsorb uranium and applicability in both column and batch systems. This adsorbent can recover uranium from natural seawater with high efficiency. The maximum adsorption capacities were 1850 μg uranium g-1 adsorbent for the tannin immobilized on agarose gel by the epichlorohydrin coupling procedure and 1062 μg g-1 adsorbent for that produced by the cyanuric chloride coupling procedure. (author)

  12. Optical investigation of diffusion of levofloxacin mesylate in agarose hydrogel

    Science.gov (United States)

    Tan, Shuaixia; Dai, Hongjun; Wu, Juejie; Zhao, Ning; Zhang, Xiaoli; Xu, Jian

    2009-09-01

    Real-time electronic speckle pattern interferometry method has been applied to study the diffusion behavior of levofloxacin mesylate (MSALVFX) in agarose hydrogel. The results show that the diffusivity of solute decreases with the increase of concentration of agarose and adapts to Kohlrausch's law. Furthermore, Amsden's model, based on the retardance effect associated with polymer chain flexibility, was employed to simulate the diffusion behavior. The consistent results suggest that the retardance effect dominates the diffusion process of MSALFVX in hydrogel; moreover, polymer chain flexibility greatly affects drug transport within the polymer matrix.

  13. Reciclagem de agarose em laboratórios de biologia molecular Recycling agarose in molecular biology laboratories

    Directory of Open Access Journals (Sweden)

    Lia Rejane Silveira Reiniger

    2004-10-01

    Full Text Available Em laboratórios de biologia molecular, a eletroforese em gel de agarose é usada, rotineiramente, para separar moléculas de ácidos nucléicos. A agarose é um polímero extraído de algas marinhas que apresenta custo elevado. O objetivo do presente trabalho consistiu na otimização de um protocolo de reciclagem deste produto, após proceder a descontaminação de brometo de etídio, possibilitando sua reutilização em eletroforese analítica. O processo, originalmente proposto por PALACIOS et al. (2000, recebeu modificações e consistiu em equilibrar a agarose em água, efetuar sua secagem e transformá-la novamente em pó, em moinho. O produto reciclado assemelhou-se ao original, apresentando grânulos ligeiramente maiores e mais escuros. Os géis foram preparados da mesma maneira que usando o produto original, não requerendo nenhum procedimento adicional. A agarose reciclada ficou disponível para uso imediato, podendo ser armazenada à temperatura ambiente, por longos períodos de tempo e ocupando uma pequena área. Presta-se à elaboração de géis analíticos das mais variadas concentrações e composições de tampão. Além disso, a reciclagem também contribui para a diminuição de resíduos sólidos descartados no meio ambiente e resulta em significativa redução de custos. Os géis com o produto reciclado mostraram desempenho semelhante na eletroforese e possibilitaram uma adequada resolução das bandas.In molecular biology laboratories, the agarose gel electrophoresis is used on a daily basis in order to separate nucleic acid molecules. The agarose is a polimere of elevated cost. The goal of the present work consisted in the optimization of a protocole of agarose recycling, transforming it, once again, into a powdery material similar to the original, after performing the decontamination of Ethidium bromide, allowing its reuse in analitycal electrophoresis. The process, originally proposed by PALACIOS et al. (2000 receveid

  14. Phenolic Molding Compounds

    Science.gov (United States)

    Koizumi, Koji; Charles, Ted; de Keyser, Hendrik

    Phenolic Molding Compounds continue to exhibit well balanced properties such as heat resistance, chemical resistance, dimensional stability, and creep resistance. They are widely applied in electrical, appliance, small engine, commutator, and automotive applications. As the focus of the automotive industry is weight reduction for greater fuel efficiency, phenolic molding compounds become appealing alternatives to metals. Current market volumes and trends, formulation components and its impact on properties, and a review of common manufacturing methods are presented. Molding processes as well as unique advanced techniques such as high temperature molding, live sprue, and injection/compression technique provide additional benefits in improving the performance characterisitics of phenolic molding compounds. Of special interest are descriptions of some of the latest innovations in automotive components, such as the phenolic intake manifold and valve block for dual clutch transmissions. The chapter also characterizes the most recent developments in new materials, including long glass phenolic molding compounds and carbon fiber reinforced phenolic molding compounds exhibiting a 10-20-fold increase in Charpy impact strength when compared to short fiber filled materials. The role of fatigue testing and fatigue fracture behavior presents some insight into long-term reliability and durability of glass-filled phenolic molding compounds. A section on new technology outlines the important factors to consider in modeling phenolic parts by finite element analysis and flow simulation.

  15. Silicon micro-mold

    Science.gov (United States)

    Morales, Alfredo M.

    2006-10-24

    The present invention describes a method for rapidly fabricating a robust 3-dimensional silicon-mold for use in preparing complex metal micro-components. The process begins by depositing a conductive metal layer onto one surface of a silicon wafer. A thin photoresist and a standard lithographic mask are then used to transfer a trace image pattern onto the opposite surface of the wafer by exposing and developing the resist. The exposed portion of the silicon substrate is anisotropically etched through the wafer thickness down to conductive metal layer to provide an etched pattern consisting of a series of rectilinear channels and recesses in the silicon which serve as the silicon micro-mold. Microcomponents are prepared with this mold by first filling the mold channels and recesses with a metal deposit, typically by electroplating, and then removing the silicon micro-mold by chemical etching.

  16. Agarose and methylcellulose hydrogel blends for nerve regeneration applications

    Science.gov (United States)

    Martin, Benton C.; Minner, Eric J.; Wiseman, Sherri L.; Klank, Rebecca L.; Gilbert, Ryan J.

    2008-06-01

    Trauma sustained to the central nervous system is a debilitating problem for thousands of people worldwide. Neuronal regeneration within the central nervous system is hindered by several factors, making a multi-faceted approach necessary. Two factors contributing to injury are the irregular geometry of injured sites and the absence of tissue to hold potential nerve guides and drug therapies. Biocompatible hydrogels, injectable at room temperature, that rapidly solidify at physiological temperatures (37 °C) are beneficial materials that could hold nerve guidance channels in place and be loaded with therapeutic agents to aid wound healing. Our studies have shown that thermoreversible methylcellulose can be combined with agarose to create hydrogel blends that accommodate these properties. Three separate novel hydrogel blends were created by mixing methylcellulose with one of the three different agaroses. Gelation time tests show that the blends solidify at a faster rate than base methylcellulose at 37 °C. Rheological data showed that the elastic modulus of the hydrogel blends rapidly increases at 37 °C. Culturing experiments reveal that the morphology of dissociated dorsal root ganglion neurons was not altered when the hydrogels were placed onto the cells. The different blends were further assessed using dissolution tests, pore size evaluations using scanning electron microscopy and measuring the force required for injection. This research demonstrates that blends of agarose and methylcellulose solidify much more quickly than plain methylcellulose, while solidifying at physiological temperatures where agarose cannot. These hydrogel blends, which solidify at physiological temperatures naturally, do not require ultraviolet light or synthetic chemical cross linkers to facilitate solidification. Thus, these hydrogel blends have potential use in delivering therapeutics and holding scaffolding in place within the nervous system.

  17. Purification of coated vesicles by agarose gel electrophoresis

    OpenAIRE

    1981-01-01

    We have applied agarose gel electrophoresis as a novel step in the purification of clathrin-coated vesicles. Preparations of coated vesicles obtained by sedimentation velocity and isopycnic centrifugation are resolved into two distinct fractions upon electrophoresis. The slower migrating fraction contains smooth vesicles, whereas the faster contains only coated vesicles and empty clathrin coats. The faster mobility of the coated vesicles is primarily caused by the acidic nature of clathrin. C...

  18. Numerical Simulation of Phenolic Sheet Molding Compound in Compression Molding

    Institute of Scientific and Technical Information of China (English)

    MEI Qi-lin; YAN Shi-lin; HUANG Zhi-xiong

    2003-01-01

    Based on generalized Hele-Shaw (GHS) model, a numerical simulation of phenolic sheet molding compound (P-SMC) in compression molding is realized by finite element step-by-step computing method. Finite elemental computing and post analysis programs have been written. The compression mold filling process, time and pressure requirements of P-SMC in a closed mold are predicted, and a good agreement is shown when compared with experiments. It will be of theoretical significance for the mold design and the optimization of the technological parameters in the compression molding of sheet molding compound.

  19. Preparation and stability of agarose microcapsules containing BCG.

    Science.gov (United States)

    Esquisabel, A; Hernandez, R M; Igartua, M; Gascón, A R; Calvo, B; Pedraz, J L

    2002-01-01

    An emulsification/internal gelation method of preparing small-sized agarose microcapsules containing Bacillus Calmette-Guerin (BCG) is reported. Agarose microcapsules have been prepared by the emulsification of the hydrogel within a vegetable oil followed by its gelation due to the cooling of the system. Four different oils (sesame, sweet almonds, camomile and jojoba) were assayed. The rheological analysis of the oils showed a Newtonian behaviour, with viscosity values of 37.7, 51.2, 59.3 and 67.1 mPa s for jojoba, camomile, sesame and sweet almonds oil, respectively. The particle size of the microcapsules obtained ranged from 23.1 microm for the microcapsules prepared with sweet almonds oil to 42.6 microm for those prepared with jojoba. The microcapsule particle size was found to be dependent on the viscosity of the oil used in the emulsification step. The encapsulated BCG was identified by the Difco TB stain set K, followed by observation under optical microscopy. Once prepared, microcapsules were freeze-dried using 5% trehalose as cryoprotectant and the stability of the microcapsules was assayed during 12 months storage at room temperature, observing that agarose microcapsules were stable after 12 months storage, since there was no evidence of alteration in the freeze-dried appearance, resuspension rate, observation under microscope, or particle size.

  20. Mold Image Library

    Science.gov (United States)

    ... Terry Brennan Example of exhaust vent in a bathroom Photo courtesy of Terry Brennan Example of an ... led to mold on paneling behind mirror above bathroom sink. (The mirror has been removed in this ...

  1. [Methodical features of the molding of diagnostic competences in medical parasitology workers].

    Science.gov (United States)

    Dovgalev, A S; Astanina, S Iu; Avdiukhina, T I; Serdiuk, A P; Imamkuliev, K D

    2015-01-01

    The paper provides a rationale for a procedure to mold diagnostic competences in medical workers of the laboratories of therapeutic-and-prophylactic institutions and hygiene and epidemiology centers, Russian Federal Service for Supervision of Consumer Rights Protection and Human Welfare. The methodical features of molding diagnostic competences in the above contingents are the design and organization of an educational process by applying systems integration and competence-based approaches; increased active self-directed learning of audience; a procedure to organize its unsupervised extracurricular activities. Professional habits and skills in laboratory specialists should be molded on the basis of didactic principles and in compliance with the found methodical patterns. The eventual result (molded competences) and its compliance with the practical health care requirements is assessed using all control types (incoming, running, intermediate, and ultimate ones). This ensures the stability and predictability of molding diagnostic competences in parasitology specialists.

  2. Transferability of glass lens molding

    Science.gov (United States)

    Katsuki, Masahide

    2006-02-01

    Sphere lenses have been used for long time. But it is well known that sphere lenses theoretically have spherical aberration, coma and so on. And, aspheric lenses attract attention recently. Plastic lenses are molded easily with injection machines, and are relatively low cost. They are suitable for mass production. On the other hand, glass lenses have several excellent features such as high refractive index, heat resistance and so on. Many aspheric glass lenses came to be used for the latest digital camera and mobile phone camera module. It is very difficult to produce aspheric glass lenses by conventional process of curve generating and polishing. For the solution of this problem, Glass Molding Machine was developed and is spreading through the market. High precision mold is necessary to mold glass lenses with Glass Molding Machine. The mold core is ground or turned by high precision NC aspheric generator. To obtain higher transferability of the mold core, the function of the molding machine and the conditions of molding are very important. But because of high molding temperature, there are factors of thermal expansion and contraction of the mold and glass material. And it is hard to avoid the factors. In this session, I introduce following items. [1] Technology of glass molding and the machine is introduced. [2] The transferability of glass molding is analyzed with some data of glass lenses molded. [3] Compensation of molding shape error is discussed with examples.

  3. Dynamic of taking out molding parts at injection molding

    Directory of Open Access Journals (Sweden)

    E. Ragan

    2012-10-01

    Full Text Available Most plastic parts used in automobile production are manufactured by injection molding. Their quality depends also on taking out molding and on the manipulators for it. Task of this contribution is to theoretically describe a transport of molding at taking out after injection molding in relation on its regulation. The following quantities are derived at it: the transition characteristic of the taking out system, the blocking diagram of taking out molding regulation, the amplitude and phase characteristic and the transition characteristic of action quantity at taking out molding regulation.

  4. Meer bekend over Black Mold

    NARCIS (Netherlands)

    Duyvesteijn, R.G.E.; Kohrman, E.

    2008-01-01

    In de vollegrondsrozenteelt zorgde Black Mold in 2007 voor een groot aantal mislukte oculaties. In 2008 waren er aanzienlijk minder problemen. Uit onderzoek is meer bekend over de oorzaak en bestrijding van Black Mold.

  5. High Cost/High Risk Components to Chalcogenide Molded Lens Model: Molding Preforms and Mold Technology

    Energy Technology Data Exchange (ETDEWEB)

    Bernacki, Bruce E.

    2012-10-05

    This brief report contains a critique of two key components of FiveFocal's cost model for glass compression molding of chalcogenide lenses for infrared applications. Molding preforms and mold technology have the greatest influence on the ultimate cost of the product and help determine the volumes needed to select glass molding over conventional single-point diamond turning or grinding and polishing. This brief report highlights key areas of both technologies with recommendations for further study.

  6. Growth in Agarose of Human Cells Infected with Cytomegalovirus

    Science.gov (United States)

    Lang, David J.; Montagnier, Luc; Latarjet, Raymond

    1974-01-01

    After infection by human cytomegalovirus (CMV), human diploid fibroblasts could grow in agarose medium for several generations. Clones of infected cells grew for weeks, although in every case they ultimately underwent lysis owing to the cytopathic effect of the virus. Virus was inoculated at high dilution and after UV irradiation in an effort to derive cells infected with noninfectious defective particles still capable of inducing cell stimulation. Dilute or irradiated virus occasionally yielded large colonies of replicating cells, although permanent transformation was not observed. One clone derived from UV-CMV-infected cells was passaged four times before undergoing lysis. During these passages the cells exhibited alterations in morphology and orientation. Images PMID:4367907

  7. DNA recovery from agarose gels with a simple centrifuge-driven sephadex filtration

    Institute of Scientific and Technical Information of China (English)

    Niu Chen; Li Yun

    2006-01-01

    Conventional methods of DNA recovery from agarose gel generally require expensive equipment, extended elution times,or considerable handling of the sample after elution. We developed a simple protocol for a quick and effective recovery of DNA from agarose gels with good yield and quality. Using a Sephadex resin filled spin column, DNA fragments of 500 bp to 6 kb in an agarose gel slice were easily recovered by a 2 min centrifugation. The recovery efficiencies were over 40%-50% and the eluted DNA can be used directly for downstream application, such as polymerase chain reactions (PCR) and restriction enzyme digestion. This method could also be used to recover large DNA fragment (48 kb) without degradation. The use of Sephadex helps to remove small molecular impurities from agarose and it also reduces the chance of clogging the column filter caused by direct contact with agarose.

  8. Characterization of agarose as an encapsulation medium for particulate specimens for transmission electron microscopy.

    Science.gov (United States)

    Wood, J I; Klomparens, K L

    1993-07-01

    Agarose, agar, and gelatin were initially compared as encapsulation media for 3 structurally diverse particulate specimens: bacteria, yeast, and mitochondria. Agarose proved superior to both gelatin and agar for ease of handling and overall image quality (minimum background). All sample types exhibited high quality fixation and structural detail with no heat damage from the agarose medium. Based on this finding, we further characterized agarose encapsulation as affected by post-fixation, en bloc staining and resin type. Osmium tetroxide post-fixation, followed by en bloc uranyl acetate staining, could be performed without an increase in the electron density of the encapsulation medium. Agarose proved successful as an encapsulation medium regardless of the resin type or preparation protocol, thus providing flexibility in experimental design and excellent results over a range of variables. PMID:8358076

  9. Compliance status

    Energy Technology Data Exchange (ETDEWEB)

    Black, D.G.

    1995-06-01

    This section of the 1994 Hanford Site Environmental Report summarizes the activities conducted to ensure that the Hanford Site is in compliance with federal environmental protection statutes and related Washington State and local environmental protection regulations and the status of Hanford`s compliance with these requirements. Environmental permits required under the environmental protection regulations are discussed under the applicable statute.

  10. Collagen and chondrocyte concentrations control ultrasound scattering in agarose scaffolds.

    Science.gov (United States)

    Inkinen, S; Liukkonen, J; Ylärinne, J H; Puhakka, P H; Lammi, M J; Virén, T; Jurvelin, J S; Töyräs, J

    2014-09-01

    Ultrasound imaging has been proposed for diagnostics of osteoarthritis and cartilage injuries in vivo. However, the specific contribution of chondrocytes and collagen to ultrasound scattering in articular cartilage has not been systematically studied. We investigated the role of these tissue structures by measuring ultrasound scattering in agarose scaffolds with varying collagen and chondrocyte concentrations. Ultrasound catheters with center frequencies of 9 MHz (7.1-11.0 MHz, -6 dB) and 40 MHz (30.1-45.3 MHz, -6 dB) were applied using an intravascular ultrasound device. Ultrasound backscattering quantified in a region of interest starting right below sample surface differed significantly (p < 0.05) with the concentrations of collagen and chondrocytes. An ultrasound frequency of 40 MHz, as compared with 9 MHz, was more sensitive to variations in collagen and chondrocyte concentrations. The present findings may improve diagnostic interpretation of arthroscopic ultrasound imaging and provide information necessary for development of models describing ultrasound propagation within cartilage. PMID:24972499

  11. Improving the culture of cucumber protoplasts by using an agarose-disc procedure

    International Nuclear Information System (INIS)

    A method is described for the isolation of protoplasts from cotyledons of cucumber (Cucumis sativus L.). After isolation, protoplasts were embedded in a mixture of agarose and Murashige and Skoog medium supplemented with 250 mg/L trypton, 2% sucrose, 5 μM naphthaleneacetic acid and 15 μM 2iP. The culture of the protoplasts was improved by the application of an agarose-disc culture procedure. The embedded protoplasts were plated in small (100 μL) droplets in Petri dishes to which, after gelling of the agarose, liquid medium was added. For comparison, protoplasts were also cultured according to the agarose-bead procedure. The plating efficiency ranged from 50 to 80% if the protoplasts were plated at high density (105 protoplasts per mL). In agarose-bead culture, divisions were induced at a lower rate. At lower densities the plating efficiency was dramatically decreased. Growth of microcalli was determined by homogenizing culture samples and measuring their density spectrophotometrically. The growth rate of the developing cell clusters was much higher in agarose-disc cultures as compared with bead-type cultures. It is concluded that for cucumber protoplasts the agarose-disc culture procedure provided optimal conditions for both the initiation of cell division and the growth of microcalli. (author)

  12. Removal of digoxin from plasma using monoclonal anti-digoxin antibodies immobilized on agarose

    Energy Technology Data Exchange (ETDEWEB)

    Brizgys, M.; Pincus, S.; Rollins, D.E.

    1986-05-01

    Monoclonal anti-digoxin antibodies (dig-Ab) have been covalently coupled to agarose supports to evaluate them as part of an extracorporeal device for removal of digoxin from the circulation. The agarose supports studied were Sepharose CL-6B, agarose-polyacrolein microsphere (APAM) beads, Bio Gel A-5m and Affi-gel 15 (Bio-Rad). Antibody concentrations between 2 and 4 mg/g gel were coupled to the agarose beads which were then placed in glass columns. Bovine ..cap alpha..-globulin coupled to the agarose supports was used as a control. Binding capacity and affinity of the immobilized antibody were determined by perfusing the dig-Ab agarose beads with a plasma solution containing /sup 3/H-digoxin and various concentrations of digoxin. The binding capacity of the immobilized dig-Ab was 30% of the theoretical value for Sepharose, Bio Gel and Affigel, and 10% of the theoretical value for dig-Ab coupled to APAM beads. The affinity of the immobilized dig-Ab was 10-100 fold less than non-immobilized Ab (3.4 x 10/sup 8/M/sup -1/. The APAM beads showed a significant decrease in binding of digoxin as the flow rate was increased from 0.5 to 5.0 ml/min. These data demonstrate that dig-Ab coupled to agarose and incorporated into a column can be used to remove digoxin from plasma in vitro.

  13. Synthesis of agarose-metal/semiconductor nanoparticles having superior bacteriocidal activity and their simple conversion to metal-carbon composites

    Indian Academy of Sciences (India)

    K K R Datta; B Srinivasan; H Balaram; M Eswaramoorthy

    2008-11-01

    Agarose, a naturally occurring biopolymer is used for the stabilization of metal, semiconductor nanoparticles. Ag and Cu nanoparticles stabilized in agarose matrix show excellent antibacterial activity against E. coli bacteria. The well dispersed metal nanoparticles within the agarose composite films can be readily converted to carbon-metal composites of catalytic importance.

  14. Nanofabrication with molds & stamps

    Directory of Open Access Journals (Sweden)

    Byron D. Gates

    2005-02-01

    Full Text Available A number of methods can be used to fabricate patterns with features having dimensions <100 nm. These techniques, however, can require specialized equipment and are often restricted to a cleanroom environment. Nanofabrication can be made accessible to multiple users by using elastomeric molds or stamps to transfer high-resolution patterns into other materials. These techniques are inexpensive and can transfer patterns into functional materials and onto a number of surfaces. This review describes recent advances in fabricating nanostructures using these techniques.

  15. Injection Compression Molding of Replica Molds for Nanoimprint Lithography

    Directory of Open Access Journals (Sweden)

    Keisuke Nagato

    2014-03-01

    Full Text Available As a breakthrough in the cost and durability of molds for nanoimprint lithography (NIL, replica molds are fabricated by injection compression molding (ICM. ICM is commonly used for optical disks such as DVDs or Blu-ray disks and is also a practical fabrication method for nanostructures. In this paper, I successfully demonstrated the fabrication of cycloolefin polymer replica molds with structures smaller than 60 nm by ICM. Furthermore, ultraviolet (UV-NIL using these replica molds was demonstrated. UV-cured resist was replicated over an area of 60 mm diameter. The degree of replication by UV-NIL in the first usage of each replica mold had good repeatability. Because ICM is a high-throughput, low-cost process, the replica mold can be disposed of after a certain time for UV-NIL. This method leads to a high-integrity UV-NIL process of patterned media because multiple large-area replica molds can be fabricated simultaneously.

  16. Mold Materials For Permanent Molding of Aluminum Alloys

    Energy Technology Data Exchange (ETDEWEB)

    John F Wallace; David Schwam; Wen Hong dxs11@po.cwru.edu

    2001-09-14

    A test that involves immersion of the potential mod materials for permanent molds has been developed that provides a thermal cycle that is similar to the experienced during casting of aluminum in permanent molds. This test has been employed to determine the relative thermal fatigue resistance of several different types of mold materials. Four commercial mold coatings have been evaluated for their insulating ability, wear resistance and roughness. The results indicate that composition and structure of the mold materials have considerable effect on their thermal fatigue cracking behavior. Irons with a gray iron structure are the most prone to thermal fatigue cracking followed by compacted graphite irons with the least thermal fatigue cracking of the cast irons experienced by ductile iron. The composition of these various irons affects their behavior.

  17. Characterization of Injection Molded Structures

    DEFF Research Database (Denmark)

    Sun, Ling; Søgaard, Emil; Andersen, Nis Korsgaard;

    Microscopy has been widely applied to understand surface structures of solid samples. According to the instrumental methodology, there are different microscopy methods: optical microscopy, electron microscopy, and scanning probe microscopy (SPM). These microscopy methods have individual advantage......-properties relationship of the injection molded polymer samples. These results are very important in optimizing injection molding parameters....

  18. Thermophilic molds: Biology and applications.

    Science.gov (United States)

    Singh, Bijender; Poças-Fonseca, Marcio J; Johri, B N; Satyanarayana, Tulasi

    2016-11-01

    Thermophilic molds thrive in a variety of natural habitats including soils, composts, wood chip piles, nesting materials of birds and other animals, municipal refuse and others, and ubiquitous in their distribution. These molds grow in simple media containing carbon and nitrogen sources and mineral salts. Polyamines are synthesized in these molds and the composition of lipids varies considerably, predominantly containing palmitic, oleic and linoleic acids with low levels of lauric, palmiotoleic and stearic acids. Thermophilic molds are capable of efficiently degrading organic materials by secreting thermostable enzymes, which are useful in the bioremediation of industrial wastes and effluents that are rich in oil, heavy metals, anti-nutritional factors such as phytic acid and polysaccharides. Thermophilic molds synthesize several antimicrobial substances and biotechnologically useful miscellaneous enzymes. The analysis of genomes of thermophilic molds reveals high G:C contents, shorter introns and intergenic regions with lesser repetitive sequences, and further confirms their ability to degrade agro-residues efficiently. Genetic engineering has aided in ameliorating the characteristics of the enzymes of thermophilic molds. This review is aimed at focusing on the biology of thermophilic molds with emphasis on recent developments in the analysis of genomes, genetic engineering and potential applications. PMID:26777293

  19. Searching for the best agarose candidate from genusGracilaria,Eucheuma,Gelidium and local brands

    Institute of Scientific and Technical Information of China (English)

    Ferry Efendi; Retno Handajani; Nursalam Nursalam

    2015-01-01

    Objective:To explore the potential of local agar of genusGracilaria,Eucheuma,Gelidium and local brandsas an alternative for imported agarose forDNA electrophoresis, and to examine their ability related to separation and migration ofDNA fragments inDNA electrophoresis. Methods:Their performance at various concentrations were compared via an experimental study with a specific brand of imported commercial agarose used in molecular biology research. The measured variables were separation and migration during electrophoresis of a DNA fragment. Results: The local agar genusGracilaria gigas,Gelidium, brand "B" and brand "S" could separateDNA fragments at a concentration between 1% and 2%, with an optimum concentration of 2% w/v, as good as a specific brand of imported commercial agarose. Conclusions:Their performance were very close to that of commercial agarose and can still be improved by further agar purification as well as by pH and sulfur control.

  20. Searching for the best agarose candidate from genus Gracilaria, Eucheuma,Gelidium and local brands简

    Institute of Scientific and Technical Information of China (English)

    Ferry; Efendi; Retno; Handajani; Nursalam; Nursalam

    2015-01-01

    Objective: To explore the potential of local agar of genus Gracilaria, Eucheuma,Gelidium and local brands as an alternative for imported agarose for DNA electrophoresis, and to examine their ability related to separation and migration of DNA fragments in DNA electrophoresis.Methods: Their performance at various concentrations were compared via an experimental study with a specific brand of imported commercial agarose used in molecular biology research. The measured variables were separation and migration during electrophoresis of a DNA fragment.Results: The local agar genus Gracilaria gigas, Gelidium, brand “B” and brand “S”could separate DNA fragments at a concentration between 1% and 2%, with an optimum concentration of 2% w/v, as good as a specific brand of imported commercial agarose.Conclusions: Their performance were very close to that of commercial agarose and can still be improved by further agar purification as well as by p H and sulfur control.

  1. Glucose and Fructose Production by Saccharomyces cerevisiae Invertase Immobilized on MANAE-Agarose Support

    Directory of Open Access Journals (Sweden)

    Antonio José Goulart

    2013-04-01

    Full Text Available Invertase from Saccharomyces cerevisiae was immobilized on agarose beads, activated with various groups (glyoxyl, MANAE or glutaraldehyde, and on some commercial epoxy supports (Eupergit and Sepabeads. Very active and stable invertase derivatives were produced by the adsorption of the enzyme on MANAE-agarose, MANAE-agarose treated with glutaraldhyde and glutaraldehyde-agarose supports. At pH 5.0, these derivatives retained full activity after 24h at 40 ºC and 50 ºC. When assayed at 40 °C and 50 °C, with the pH adjusted to 7.0, the invertase-MANAEagarose derivative treated with glutaraldehyde retained 80% of the initial activity. Recovered activities of the derivatives produced with MANAE, MANAE treated with glutaraldehyde and glutaraldehyde alone were 73.5%, 44.4% and 36.8%, respectively. These three preparations were successfully employed to produce glucose and fructose in 3 cycles of sucrose hydrolysis.

  2. Agarose gel shift assay reveals that calreticulin favors substrates with a quaternary structure in solution

    DEFF Research Database (Denmark)

    Boelt, Sanne Grundvad; Houen, Gunnar; Højrup, Peter

    2015-01-01

    Here we present an agarose gel shift assay that, in contrast to other electrophoresis approaches, is loaded in the center of the gel. This allows proteins to migrate in either direction according to their isoelectric points. Therefore, the presented assay enables a direct visualization, separation...... structure. It is also demonstrated that the agarose gel shift assay is useful in the study of other protein interactions and can be used as an alternative method to native polyacrylamide gel electrophoresis....

  3. A microfluidic device for on-chip agarose microbead generation with ultralow reagent consumption.

    Science.gov (United States)

    Desbois, Linda; Padirac, Adrien; Kaneda, Shohei; Genot, Anthony J; Rondelez, Yannick; Hober, Didier; Collard, Dominique; Fujii, Teruo

    2012-01-01

    Water-in-oil microdroplets offer microreactors for compartmentalized biochemical reactions with high throughput. Recently, the combination with a sol-gel switch ability, using agarose-in-oil microdroplets, has increased the range of possible applications, allowing for example the capture of amplicons in the gel phase for the preservation of monoclonality during a PCR reaction. Here, we report a new method for generating such agarose-in-oil microdroplets on a microfluidic device, with minimized inlet dead volume, on-chip cooling, and in situ monitoring of biochemical reactions within the gelified microbeads. We used a flow-focusing microchannel network and successfully generated agarose microdroplets at room temperature using the "push-pull" method. This method consists in pushing the oil continuous phase only, while suction is applied to the device outlet. The agarose phase present at the inlet is thus aspirated in the device, and segmented in microdroplets. The cooling system consists of two copper wires embedded in the microfluidic device. The transition from agarose microdroplets to microbeads provides additional stability and facilitated manipulation. We demonstrate the potential of this method by performing on-chip a temperature-triggered DNA isothermal amplification in agarose microbeads. Our device thus provides a new way to generate microbeads with high throughput and no dead volume for biochemical applications. PMID:24106525

  4. Functional nanostructures on injection molded plastic

    DEFF Research Database (Denmark)

    Johansson, Alicia Charlotte; Søgaard, Emil; Andersen, Nis Korsgaard;

    Nanotechnology can be used to make inexpensive plastic parts with functional surfaces. The plastic parts can be molded using a standard injection molding process. The nanostructures are directly transferred from the surface of the molding tool to the surface of the molded plastic part during...

  5. Injection Molding of High Aspect Ratio Nanostructures

    DEFF Research Database (Denmark)

    Matschuk, Maria; Larsen, Niels Bent

    We present a process for injection molding of 40 nm wide and >100 nm high pillars (pitch: 200 nm). We explored the effects of mold coatings and injection molding conditions on the replication quality of nanostructures in cyclic olefin copolymer. We found that optimization of molding parameters...

  6. Rapid control of mold temperature during injection molding process

    Energy Technology Data Exchange (ETDEWEB)

    Liparoti, Sara; Titomanlio, Giuseppe [Department of Industrial Engineering, University of Salerno Via Giovanni Paolo II, 132, 84084 Fisciano (Italy); Hunag, Tsang Min; Cakmak, Mukerrem [Department of Polymer Engineering, The University of Akron, Akron, OH 44325 (United States); Sorrentino, Andrea [Institute for Polymers, Composite and Biomaterials (IPCB) - CNR, P. Enrico Fermi 1, 80055 Portici (Italy)

    2015-05-22

    The control of mold surface temperature is an important factor that determines surface morphology and its dimension in thickness direction. It can also affect the frozen molecular orientation and the mold surface replicability in injection molded products. In this work, thin thermally active films were used to quickly control the mold surface temperature. In particular, an active high electrical conductivity carbon black loaded polyimide composites sandwiched between two insulating thin polymeric layers was used to condition the mold surface. By controlling the heating time, it was possible to control precisely the temporal variation of the mold temperature surface during the entire cycle. The surface heating rate was about 40°C/s and upon contact with the polymer the surface temperature decreased back to 40°C within about 5 s; the overall cycle time increased only slightly. The effect on cross section sample morphology of samples of iPP were analyzed and discussed on the basis of the recorded temperature evolution.

  7. White mold of Jerusalem artichoke

    Science.gov (United States)

    Jerusalem artichoke (Helianthus tuberosus) is a Native American food plant closely related to the common sunflower (Helianthus annuus). Tubers of Jerusalem artichoke are increasingly available in retail grocery outlets. White mold (Sclerotinia stem rot), caused by the fungus, Sclerotinia sclerotioru...

  8. Rapid agarose gel electrophoretic mobility shift assay for quantitating protein: RNA interactions.

    Science.gov (United States)

    Ream, Jennifer A; Lewis, L Kevin; Lewis, Karen A

    2016-10-15

    Interactions between proteins and nucleic acids are frequently analyzed using electrophoretic mobility shift assays (EMSAs). This technique separates bound protein:nucleic acid complexes from free nucleic acids by electrophoresis, most commonly using polyacrylamide gels. The current study utilizes recent advances in agarose gel electrophoresis technology to develop a new EMSA protocol that is simpler and faster than traditional polyacrylamide methods. Agarose gels are normally run at low voltages (∼10 V/cm) to minimize heating and gel artifacts. In this study we demonstrate that EMSAs performed using agarose gels can be run at high voltages (≥20 V/cm) with 0.5 × TB (Tris-borate) buffer, allowing for short run times while simultaneously yielding high band resolution. Several parameters affecting band and image quality were optimized for the procedure, including gel thickness, agarose percentage, and applied voltage. Association of the siRNA-binding protein p19 with its target RNA was investigated using the new system. The agarose gel and conventional polyacrylamide gel methods generated similar apparent binding constants in side-by-side experiments. A particular advantage of the new approach described here is that the short run times (5-10 min) reduce opportunities for dissociation of bound complexes, an important concern in non-equilibrium nucleic acid binding experiments. PMID:27495142

  9. Hydrogen silsesquioxane mold coatings for improved replication of nanopatterns by injection molding

    DEFF Research Database (Denmark)

    Hobæk, Thor Christian; Matschuk, Maria; Kafka, Jan;

    2015-01-01

    We demonstrate the replication of nanosized pillars in polymer (cyclic olefin copolymer) by injection molding using nanostructured thermally cured hydrogen silsesquioxane (HSQ) ceramic coatings on stainless steel mold inserts with mold nanostructures produced by a simple embossing process...

  10. Plasticizing effect of choline chloride/urea eutectic-based ionic liquid on physicochemical properties of agarose films

    Directory of Open Access Journals (Sweden)

    Ahmad Adlie Shamsuri

    2012-11-01

    Full Text Available Agarose films were formed with the addition of 30 to 70 wt% choline chloride/urea eutectic-based ionic liquid (ChCl/Urea. The ChCl/Urea was prepared through complexation at a 1:2 mole ratio. The films were prepared by dissolving ChCl/Urea in distilled water followed by dispersion of the agarose at 95 °C. The solution was gelled at room temperature, and the formed gel was dried in an oven overnight at 70 °C. Mechanical testing indicated that the agarose film containing 60 wt% ChCl/Urea had higher tensile extension and tensile strain at break compared to the pristine agarose film. The addition of ChCl/Urea also reduced the glass transition temperature (Tg of agarose films. Cross-section SEM images of the agarose films showed that surface roughness disappeared with the incorporation of ChCl/Urea. FTIR spectra confirmed the presence of intermolecular hydrogen bonding between agarose and ChCl/Urea. XRD patterns demonstrated that an amorphous phase was obtained when ChCl/Urea was added. Agarose films containing more ChCl/Urea exhibited higher transparency, as measured by a UV-Vis spectrometer. In summary, the physicochemical properties of agarose films were evidently affected by the incorporation of the ChCl/Urea as a plasticizing agent.

  11. Agarose- and alginate-based biopolymers for sample preparation: Excellent green extraction tools for this century.

    Science.gov (United States)

    Sanagi, Mohd Marsin; Loh, Saw Hong; Wan Ibrahim, Wan Nazihah; Pourmand, Neda; Salisu, Ahmed; Wan Ibrahim, Wan Aini; Ali, Imran

    2016-03-01

    Recently, there has been considerable interest in the use of miniaturized sample preparation techniques before the chromatographic monitoring of the analytes in unknown complex compositions. The use of biopolymer-based sorbents in solid-phase microextraction techniques has achieved a good reputation. A great variety of polysaccharides can be extracted from marine plants or microorganisms. Seaweeds are the major sources of polysaccharides such as alginate, agar, agarose, as well as carrageenans. Agarose and alginate (green biopolymers) have been manipulated for different microextraction approaches. The present review is focused on the classification of biopolymer and their applications in multidisciplinary research. Besides, efforts have been made to discuss the state-of-the-art of the new microextraction techniques that utilize commercial biopolymer interfaces such as agarose in liquid-phase microextraction and solid-phase microextraction.

  12. Fabrication of Self-Healable and Patternable Polypyrrole/Agarose Hybrid Hydrogels for Smart Bioelectrodes.

    Science.gov (United States)

    Park, Nokyoung; Chae, Seung Chul; Kim, Il Tae; Hur, Jaehyun

    2016-02-01

    We present a new class of electrically conductive, mechanically moldable, and thermally self-healable hybrid hydrogels. The hybrid gels consist of polypyrrole and agarose as the conductive component and self-healable matrix, respectively. By using the appropriate oxidizing agent under conditions of mild temperature, the polymerization of pyrrole occurred along the three-dimensional network of the agarose hydrogel matrix. In contrast to most commercially available hydrogels, the physical crosslinking of agarose gel allows for reversible gelation in the case of our hybrid gel, which could be manipulated by temperature variation, which controls the electrical on/off behavior of the hybrid gel electrode. Exploiting this property, we fabricated a hybrid conductive hydrogel electrode which also self-heals thermally. The novel composite material we report here will be useful for many technological and biological applications, especially in reactive biomimetic functions and devices, artificial muscles, smart membranes, smart full organic batteries, and artificial chemical synapses. PMID:27433594

  13. Fenugreek hydrogel-agarose composite entrapped gold nanoparticles for acetylcholinesterase based biosensor for carbamates detection.

    Science.gov (United States)

    Kestwal, Rakesh Mohan; Bagal-Kestwal, Dipali; Chiang, Been-Huang

    2015-07-30

    A biosensor was fabricated to detect pesticides in food samples. Acetylcholinesterase was immobilized in a novel fenugreek hydrogel-agarose matrix with gold nanoparticles. Transparent thin films with superior mechanical strength and stability were obtained with 2% fenugreek hydrogel and 2% agarose. Immobilization of acetylcholinesterase on the membrane resulted in high enzyme retention efficiency (92%) and a significantly prolonged shelf life of the enzyme (half-life, 55 days). Transmission electron microscopy revealed that, gold nanoparticles (10-20 nm in diameter) were uniformly dispersed in the fenugreek hydrogel-agarose-acetylcholinesterase membrane. This immobilized enzyme-gold nanoparticle dip-strip system detected various carbamates, including carbofuran, oxamyl, methomyl, and carbaryl, with limits of detection of 2, 21, 113, and 236 nM (S/N = 3), respectively. Furthermore, the fabricated biosensor exhibited good testing capabilities when used to detect carbamates added to various fruit and vegetable samples. PMID:26320646

  14. Comparison of viability of adipose-derived Mesenchymal stem cells on agarose and fibrin glue scaffolds

    Directory of Open Access Journals (Sweden)

    Farzaneh Tafvizi

    2015-06-01

    Full Text Available Background & aim: Utilizing tissue engineering techniques and designing similar structures of the damaged tissues require the use of tools such as scaffolds, cells, and bioactive molecules in vitro. Meanwhile, appropriate cell cultures with the ability to divide and differentiate on the natural scaffolds lacking features like immunogenicity and tumorgenesis is particularly important. Adipose tissue has attracted researchers’ attention due to its abundance of mesenchymal stem cells and its availability through a liposuction. The purpose of the present study was to investigate the reproducibility and viability of the adipose-derived stem cells on natural scaffolds of fibrin glue and agarose. Methods: In the present experimental study, the isolation and identification of the mesenchymal stem cells was performed on tissue obtained from liposuction. The tissues were extensively washed with PBS and were digested with collagenase I, then the mesenchymal stem cells were isolated. The cells were cultured in RPMI medium supplemented with antibiotic. Subsequently, the expression of cell surface markers including CD34, CD44, CD90, and CD105 were analyzed by flow cytometry to confirm the mesenchymal cells. After preparing fibrin glue and agarose scaffolds, the viability and proliferation of the adipose tissue-derived mesenchymal stem cells were examined at the period of 24, 48, and 72 hours by MTT and ELISA assays. The obtained results were analyzed by SPSS ver.19. Results: The results of adipose tissue-derived mesenchymal stem cells culture on the fibrin glue and agarose scaffolds indicated that cell viability on fibrin glue and agarose scaffold were 68.22% and 89.75% in 24 hrs, 64.04% and 66.97% in 48 hours, 222.87% and 1089.68% in 72 hours respectively. Significant proliferation and viability cells on a synthesized agarose scaffold were seen compared to the fibrin glue scaffold after 72 hrs. The viability of the cells significantly increased on the

  15. Ag-nanoparticle fractionation by low melting point agarose gel electrophoresis

    Energy Technology Data Exchange (ETDEWEB)

    Guarrotxena, Nekane, E-mail: nekane@ictp.csic.es [Consejo Superior de Investigaciones Cientificas (CSIC), Instituto de Ciencia y Tecnologia de Polimeros (ICTP) (Spain); Braun, Gary [University of California, Santa Barbara, Department of Chemistry and Biochemistry (United States)

    2012-10-15

    The separation of surface-enhanced raman scattering (SERS)-active Ag-multi-nanoparticle (NP) assemblies by low melting point agarose gel electrophoresis was accomplished here by controlling surface charge using NP capping agents, and the pore size of agarose gel matrix. Detailed transmission electron microscopy analysis of excised gel fractions showed dimers and small clusters to have the greatest SERS activity and a mobility in between the monomers and large aggregates. This strategy enables one to: (1) stabilize small multispherical Ag clusters against further aggregation during purification; (2) fractionate and recover spherical assemblies by nuclearity; and (3) analyze SERS-enhancements for each fraction to optimize purification conditions.

  16. Micropatterning of a stretchable conductive polymer using inkjet printing and agarose stamping

    DEFF Research Database (Denmark)

    Hansen, Thomas Steen; Hassager, Ole; Larsen, Niels Bent;

    2007-01-01

    A highly conducting stretchable polymer material has been patterned using additive inkjet printing and by subtractive agarose stamping of a deactivation agent (hypochlorite). The material consisted of elastomeric polyurethane combined in an interpenetrating network with a conductive polymer, poly(3......,4-ethylenedioxythiophene) (PEDOT). The agarose stamping produced 50 μm wide conducting lines with high spatial fidelity. The deactivation agent was found to cause some degradation of the remaining conducting lines, as revealed by a stronger increase in resistance upon straining compared to the pristine polymer material...

  17. Enhanced Resolution of DNA Separation Using Agarose Gel Electrophoresis Doped with Graphene Oxide.

    Science.gov (United States)

    Li, Jialiang; Yang, Yushi; Mao, Zhou; Huang, Wenjie; Qiu, Tong; Wu, Qingzhi

    2016-12-01

    In this work, a novel agarose gel electrophoresis strategy has been developed for separation of DNA fragments by doping graphene oxide (GO) into agarose gel. The results show that the addition of GO into agarose gel significantly improved the separation resolution of DNA fragments by increasing the shift distances of both the single DNA fragments and the adjacent DNA fragments and completely eliminating the background noise derived from the diffusion of the excessive ethidium bromide (EB) dye in the gel after electrophoresis. The improved resolution of DNA fragments in GO-doped agarose gel could be attributed to the successive adsorption-desorption processes between DNA fragments and GO sheets, while the elimination of the background noise could be attributed to the adsorption of the excessive EB dye on the surface of GO sheets and high fluorescence quenching efficiency of GO. These results provide promising potential for graphene and its derivate utilized in various electrophoresis techniques for separation and detection of DAN fragments and other biomolecules. PMID:27637896

  18. A simple immunoblotting method after separation of proteins in agarose gel

    DEFF Research Database (Denmark)

    Koch, C; Skjødt, K; Laursen, I

    1985-01-01

    A simple and sensitive method for immunoblotting of proteins after separation in agarose gels is described. It involves transfer of proteins onto nitrocellulose paper simply by diffusion through pressure, a transfer which only takes about 10 min. By this method we have demonstrated the existence ...

  19. Enhanced Resolution of DNA Separation Using Agarose Gel Electrophoresis Doped with Graphene Oxide

    Science.gov (United States)

    Li, Jialiang; Yang, Yushi; Mao, Zhou; Huang, Wenjie; Qiu, Tong; Wu, Qingzhi

    2016-09-01

    In this work, a novel agarose gel electrophoresis strategy has been developed for separation of DNA fragments by doping graphene oxide (GO) into agarose gel. The results show that the addition of GO into agarose gel significantly improved the separation resolution of DNA fragments by increasing the shift distances of both the single DNA fragments and the adjacent DNA fragments and completely eliminating the background noise derived from the diffusion of the excessive ethidium bromide (EB) dye in the gel after electrophoresis. The improved resolution of DNA fragments in GO-doped agarose gel could be attributed to the successive adsorption-desorption processes between DNA fragments and GO sheets, while the elimination of the background noise could be attributed to the adsorption of the excessive EB dye on the surface of GO sheets and high fluorescence quenching efficiency of GO. These results provide promising potential for graphene and its derivate utilized in various electrophoresis techniques for separation and detection of DAN fragments and other biomolecules.

  20. Effect of alternation of agar and agarose on the green plant differentiation frequency of calli from wild rice

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    @@ In vitro culture of wild rice was difficult. Recently, we found that high agarose concentration of different media could improve the green plant differentiation frequency of calli from wild rice. We tested the effectiveness of alternation of agar and agarose in different media.

  1. Facts about Stachybotrys chartarum and Other Molds

    Science.gov (United States)

    ... are toxigenic, meaning they can produce toxins (specifically mycotoxins), the molds themselves are not toxic, or poisonous. Hazards presented by molds that may produce mycotoxins should be considered the same as other common ...

  2. Molds on Food: Are They Dangerous?

    Science.gov (United States)

    ... What Are Some Common Foodborne Molds? What Are Mycotoxins? What is Aflatoxin? How Does the U.S. Government ... a few molds, in the right conditions, produce "mycotoxins," poisonous substances that can make people sick. When ...

  3. Silane based coating of aluminium mold

    DEFF Research Database (Denmark)

    2013-01-01

    having at least one closed cavity is provided, at least one surface of the at least one cavity being an aluminium surface coated with a silane based coating layer. The silane based anti-stiction coating improves the anti-stiction properties of the mold which may allow for molding and demolding...... of structures which would otherwise be difficult to mold. The resistance of the coated aluminium mold is significantly improved by applying a silane-based coating layer....

  4. Surface microstructure replication in injection molding

    DEFF Research Database (Denmark)

    Theilade, Uffe Arlø; Hansen, Hans Nørgaard

    2006-01-01

    In recent years, polymer components with surface microstructures have been in rising demand for applications such as lab-on-a-chip and optical components. Injection molding has proven to be a feasible and efficient way to manufacture such components. In injection molding, the mold surface topogra...

  5. Injection molded self-cleaning surfaces

    DEFF Research Database (Denmark)

    Søgaard, Emil

    - and microstructured silicon is electroplated with nickel and the resulting nickel shim with inverse polarity is used in an injection molding process. A versatile injection molding process capable of producing different nano- and microstructures on areas larger than 10 cm2 is developed. Variotherm mold heating is used...

  6. Injection Molding of Plastics from Agricultural Materials

    Energy Technology Data Exchange (ETDEWEB)

    Bhattacharya, M.; Ruan, R.

    2001-02-22

    The objective of this research was to conduct a systematic study to relate injection molding parameters to properties of blends of starch and synthetic polymer. From this study, we wished to develop a thorough understanding of the injection molding process and gain significant insight into designing molds and aiding in developing products cheaply and efficiently.

  7. Stochastic resin transfer molding process

    CERN Document Server

    Park, M

    2016-01-01

    We consider one-dimensional and two-dimensional models of stochastic resin transfer molding process, which are formulated as random moving boundary problems. We study their properties, analytically in the one-dimensional case and numerically in the two-dimensional case. We show how variability of time to fill depends on correlation lengths and smoothness of a random permeability field.

  8. Injection molding ceramics to high green densities

    Science.gov (United States)

    Mangels, J. A.; Williams, R. M.

    1983-01-01

    The injection molding behavior of a concentrated suspension of Si powder in wax was studied. It was found that the injection molding behavior was a function of the processing techniques used to generate the powder. Dry ball-milled powders had the best molding behavior, while air classified and impact-milled powders demonstrated poorer injection moldability. The relative viscosity of these molding batches was studied as a function of powder properties: distribution shape, surface area, packing density, and particle morphology. The experimental behavior, in all cases, followed existing theories. The relative viscosity of an injection molding composition composed of dry ball-milled powders could be expressed using Farris' relation.

  9. Agarose functionalization: Synthesis of PEG-agarose amino acid nano-conjugate - its structural ramifications and interactions with BSA in a varying pH regime.

    Science.gov (United States)

    Chudasama, Nishith A; Prasad, Kamalesh; Siddhanta, Arup Kumar

    2016-10-20

    In a rapid one-step method protein-mimicking large agarose amino acid framework (AAE; GPC 156.7kDa) was conjugated with polyethylene glycol (PEG 9kDa) affording nano-sized PEGylated amphoteric agarose (PEG-AAE; amino, carboxyl and ester groups [overall degree of substitution (DS) 0.91]. The PEG groups were at the residual free carboxylic acid groups of succinate half-ester moiety at C-6 positions of the 1, 3 β-d-galactopyranose moieties of AAE. This new nano-sized PEG-AAE performed like a giant protein conjugate (GPC 331.2kDa) and exhibited pH-responsive interconversion between the triple helix and single-stranded random structures (optical rotatory dispersion) presenting a mixed solubility pattern like random coil (soluble), helical (soluble) and aggregate (precipitation) formations. Circular dichroism studies showed its pH-dependent complexation and decomplexation with bovine serum albumin (BSA). Such pH-responsive PEG-conjugate may be of pronounced therapeutic potential in the area of pharmacology as well as in sensing applications. PMID:27474620

  10. Pulsatile dynamic stiffness of cartilage-like materials and use of agarose gels to validate mechanical methods and models.

    Science.gov (United States)

    Scandiucci de Freitas, P; Wirz, D; Stolz, M; Göpfert, B; Friederich, N-F; Daniels, A U

    2006-08-01

    Stiffness is a fundamental indicator of the functional state of articular cartilage. Reported test modes include compressive incremental strain to determine the equilibrium modulus, and sinusoidal strain to determine the dynamic modulus and stress/strain loss angle. Here, initial development is described for a method recognizing that gait is pulsatile. Agarose gels have been used by others for validation or comparison of mechanical test methods and models for cartilage and proteoglycan aggregate. Accordingly, gels ranging from 0.5 to 20% agarose were prepared. Pulsatile stiffness in both indentation and unconfined compression were closely reproducible. Stiffness as a function of agarose concentration rose exponentially, as found using other methods. Indentation stiffness was higher than for unconfined compression and ranged from approximately 2.0 kPa for 0.5% gel to approximately 3,800 kPa for 20% gel. Pulsatile dynamic stiffness appears to be a useful method, although further development is needed. Agarose gel stiffness values obtained by other methods were reviewed for comparison. Unfortunately, reported values for a given agarose concentration ranged widely (e.g. fourfold) even when test methods were similar. Causes appear to include differences in molecular weight and gel preparation time-temperature regimens. Also, agarose is hygroscopic, leading to unintended variations in gel composition. Agarose gels are problematic materials for validation or comparison of cartilage mechanical test methods and models. PMID:16470817

  11. Numerical Analysis of Mold Deformation Including Plastic Melt Flow During Injection Molding

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Joon Tae; Lee, Bong-Kee [Chonnam National University, Gwangju (Korea, Republic of)

    2014-07-15

    In the present study, a numerical analysis of an injection molding process was conducted for predicting the mold deformation considering non-Newtonian flow, heat transfer, and structural behavior. The accurate prediction of mold deformation during the filling stage is important to successfully design and manufacture a precision injection mold. While the local mold deformation can be caused by various factors, a pressure induced by the polymer melt is considered to be one of the most significant ones. In this regard, the numerical simulation considering both the melt filling and the mold deformation was carried out. A mold core for a 2D axisymmetric center-gated disk was used for the demonstration of the present study. The flow behavior inside the mold cavity and temperature distribution were analyzed along with the core displacement. Also, a Taguchi method was employed to investigate the influence of the relevant parameters including flow velocity, mold core temperature, and melt temperature.

  12. Preparation and structural characterization of O-acetyl agarose with low degree of substitution

    Directory of Open Access Journals (Sweden)

    Rosangela B. Garcia

    2000-09-01

    Full Text Available Among the biodegradable polymers, the polysaccharides have been found to be promising carriers for bioactive molecules. From a general standpoint, they present several reactive groups, such as hydroxyl, carboxyl and amine, that can be modified in a number of ways, giving rise to suitable devices for controlled release. In this paper, agarose was submitted to O-acetylation reactions under heterogeneous conditions, using acetic anhydride and pyridine, aiming to observe the effect of acetyl groups on the agarose properties. The products were characterized by Infrared and ¹H NMR spectroscopies. In the range of average acetylation degrees (DA 0.07-0.48, the polymers presented partial solubility in boiling water and in common organic solvents. The ¹H NMR spectra presented evidences of non-homogeneous acetyl group distribution along the chains, as concluded from the solubility of only one of the fractions with DA<0.09, in boiling water .

  13. Preparation of berbamine loaded chitosan-agarose microspheres and in vitro release study

    Directory of Open Access Journals (Sweden)

    Zhang Hu

    2012-01-01

    Full Text Available Berbamine loaded chitosan-agarose microspheres were prepared using a water-in-oil emulsion technique. Optimum preparing parameters were determined by orthogonal experiments as follows: ratio of berbamine to chitosan (w/w is 1:10; percentage of emulsifier (span 80, v/v is 6%; volume of glutaraldehyde is 2 mL; and reaction temperature is 70 ºC. Under these optimal conditions, the encapsulation efficiency and loading capacity of microspheres are 84.57% and 8.44%, respectively. The swelling tests showed that the microspheres possessed higher swelling ratio at pH 7.4 than at pH 1.2. FTIR indicated that berbamine had been successfully loaded in the chitosan-agarose microspheres by physical entrapment. In vitro release studies showed that berbamine was released from microspheres in a significantly sustained fashion.

  14. Recovery of DNA from Agarose Gel with Home-made Silica Milk

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    An usefulness of silica milk made with waste ultraviolet light tube for recovery of DNA fragment from agarose gel was represented. The glass milk is a water suspension of 50% fine silica powder prepared by grinding the crushed waste ultraviolet light tube with a porcelain mortar.It was showed that one microliter of the glass milk could bind more than 1 μg of DNA fragment,and DNA fragment in length from 125 bp to 23 kb could be efficiently recovered from agarose gel. The bound DNA could be eluted from the particle of SiO2 in the glass milk with a yield of about 60%-80%.The eluted DNA could be used in all manipulations in molecular cloning.

  15. Compression molding of aerogel microspheres

    Energy Technology Data Exchange (ETDEWEB)

    Pekala, R.W.; Hrubesh, L.W.

    1998-03-24

    An aerogel composite material produced by compression molding of aerogel microspheres (powders) mixed together with a small percentage of polymer binder to form monolithic shapes in a cost-effective manner is disclosed. The aerogel composites are formed by mixing aerogel microspheres with a polymer binder, placing the mixture in a mold and heating under pressure, which results in a composite with a density of 50--800 kg/m{sup 3} (0.05--0.80 g/cc). The thermal conductivity of the thus formed aerogel composite is below that of air, but higher than the thermal conductivity of monolithic aerogels. The resulting aerogel composites are attractive for applications such as thermal insulation since fabrication thereof does not require large and expensive processing equipment. In addition to thermal insulation, the aerogel composites may be utilized for filtration, ICF target, double layer capacitors, and capacitive deionization. 4 figs.

  16. Compression molding of aerogel microspheres

    Energy Technology Data Exchange (ETDEWEB)

    Pekala, Richard W. (Pleasant Hill, CA); Hrubesh, Lawrence W. (Pleasanton, CA)

    1998-03-24

    An aerogel composite material produced by compression molding of aerogel microspheres (powders) mixed together with a small percentage of polymer binder to form monolithic shapes in a cost-effective manner. The aerogel composites are formed by mixing aerogel microspheres with a polymer binder, placing the mixture in a mold and heating under pressure, which results in a composite with a density of 50-800 kg/m.sup.3 (0.05-0.80 g/cc). The thermal conductivity of the thus formed aerogel composite is below that of air, but higher than the thermal conductivity of monolithic aerogels. The resulting aerogel composites are attractive for applications such as thermal insulation since fabrication thereof does not require large and expensive processing equipment. In addition to thermal insulation, the aerogel composites may be utilized for filtration, ICF target, double layer capacitors, and capacitive deionization.

  17. Mesoscopic gel at low agarose concentration in water: a dynamic light scattering study.

    OpenAIRE

    Bulone, D; San Biagio, P L

    1995-01-01

    Previous work in our laboratory has shown that at very low agarose concentration in water gelation still occurs within mutually disconnected, high concentration regions generated by spinodal demixing. The freely diffusing particles obtained in these conditions are studied in the present work by depolarized dynamic light scattering and probe diffusion experiments. These particles are found to behave as large (in fact, mesoscopic) polymer fibers entangled in a continuously rearranged mesh with ...

  18. Kinetic model for whey protein hydrolysis by alcalase multipoint-immobilized on agarose gel particles

    OpenAIRE

    Sousa Jr R.; Lopes G. P.; Tardioli P. W.; Giordano R.L.C.; Almeida P. I. F.; Giordano R. C.

    2004-01-01

    Partial hydrolysis of whey proteins by enzymes immobilized on an inert support can either change or evidence functional properties of the produced peptides, thereby increasing their applications. The hydrolysis of sweet cheese whey proteins by alcalase, which is multipoint-immobilized on agarose gel, is studied here. A Michaelis-Menten model that takes into account competitive inhibition by the product was fitted to experimental data. The influence of pH on the kinetic parameters in the range...

  19. Fenugreek hydrogel–agarose composite entrapped gold nanoparticles for acetylcholinesterase based biosensor for carbamates detection

    Energy Technology Data Exchange (ETDEWEB)

    Kestwal, Rakesh Mohan; Bagal-Kestwal, Dipali; Chiang, Been-Huang, E-mail: bhchiang@ntu.edu.tw

    2015-07-30

    A biosensor was fabricated to detect pesticides in food samples. Acetylcholinesterase was immobilized in a novel fenugreek hydrogel–agarose matrix with gold nanoparticles. Transparent thin films with superior mechanical strength and stability were obtained with 2% fenugreek hydrogel and 2% agarose. Immobilization of acetylcholinesterase on the membrane resulted in high enzyme retention efficiency (92%) and a significantly prolonged shelf life of the enzyme (half-life, 55 days). Transmission electron microscopy revealed that, gold nanoparticles (10–20 nm in diameter) were uniformly dispersed in the fenugreek hydrogel–agarose–acetylcholinesterase membrane. This immobilized enzyme-gold nanoparticle dip-strip system detected various carbamates, including carbofuran, oxamyl, methomyl, and carbaryl, with limits of detection of 2, 21, 113, and 236 nM (S/N = 3), respectively. Furthermore, the fabricated biosensor exhibited good testing capabilities when used to detect carbamates added to various fruit and vegetable samples. - Highlights: • Acetylcholinesterase (AChE) dip-strip biosensor fabricated to detect carbamates. • AChE entrapped in fenugreek hydrogel–agarose matrix with gold nanoparticles (GNPs). • High enzyme retention efficiency (92%) and shelf life (half-life, 55 days). • Detection limits of carbofuran, oxamyl and methomyl: 2, 21 and 113 nM. • The biosensor had good testing capabilities to detect carbamates in food samples.

  20. Retention of gene expression in porcine islets after agarose encapsulation and long-term culture.

    Science.gov (United States)

    Dumpala, Pradeep R; Holdcraft, Robert W; Martis, Prithy C; Laramore, Melissa A; Parker, Thomas S; Levine, Daniel M; Smith, Barry H; Gazda, Lawrence S

    2016-08-01

    Agarose encapsulation of porcine islets allows extended in vitro culture, providing ample time to determine the functional capacity of the islets and conduct comprehensive microbiological safety testing prior to implantation as a treatment for type 1 diabetes mellitus. However, the effect that agarose encapsulation and long-term culture may have on porcine islet gene expression is unknown. The aim of the present study was to compare the transcriptome of encapsulated porcine islets following long-term in vitro culture against free islets cultured overnight. Global gene expression analysis revealed no significant change in the expression of 98.47% of genes. This indicates that the gene expression profile of free islets is highly conserved following encapsulation and long-term culture. Importantly, the expression levels of genes that code for critical hormones secreted by islets (insulin, glucagon, and somatostatin) as well as transcripts encoding proteins involved in their packaging and secretion are unchanged. While a small number of genes known to play roles in the insulin secretion and insulin signaling pathways are differentially expressed, our results show that overall gene expression is retained following islet isolation, agarose encapsulation, and long-term culture. PMID:27261433

  1. Preparation of uniform-sized agarose beads by microporous membrane emulsification technique.

    Science.gov (United States)

    Zhou, Qing-Zhu; Wang, Lian-Yan; Ma, Guang-Hui; Su, Zhi-Guo

    2007-07-01

    Uniform-sized agarose beads were prepared by membrane emulsification technique in this study. Agarose was dissolved in boiling water (containing 0.9% sodium chloride) and used as water phase. A mixture of liquid paraffin and petroleum ether containing 4 wt% of hexaglycerin penta ester (PO-500) emulsifier was used as oil phase. At 55 degrees C, the water phase permeated through uniform pores of microporous membrane into the oil phase by a pressure of nitrogen gas to form uniform W/O emulsion. Then the emulsion was cooled down to room temperature under gentle agitation to form gel beads. The effect of oil phase, emulsifier, especially temperature on the uniformity of the beads were investigated and interpreted from interfacial tension between water phase and oil phase. Under optimized condition, the coefficient variation (C.V.) showing the size distribution of the beads was under 15%. This was the first report to prepare uniform agarose beads by membrane emulsification, and to investigate the effect of temperature on the size distribution of the droplets and beads. The beads with different size can be prepared by using membranes with different pore size, and the result showed that there was a linear relationship between the average diameter of beads and pore size of the membranes; beads with diameter from 15 to 60 microm were able to obtain in this study. PMID:17362974

  2. Fenugreek hydrogel–agarose composite entrapped gold nanoparticles for acetylcholinesterase based biosensor for carbamates detection

    International Nuclear Information System (INIS)

    A biosensor was fabricated to detect pesticides in food samples. Acetylcholinesterase was immobilized in a novel fenugreek hydrogel–agarose matrix with gold nanoparticles. Transparent thin films with superior mechanical strength and stability were obtained with 2% fenugreek hydrogel and 2% agarose. Immobilization of acetylcholinesterase on the membrane resulted in high enzyme retention efficiency (92%) and a significantly prolonged shelf life of the enzyme (half-life, 55 days). Transmission electron microscopy revealed that, gold nanoparticles (10–20 nm in diameter) were uniformly dispersed in the fenugreek hydrogel–agarose–acetylcholinesterase membrane. This immobilized enzyme-gold nanoparticle dip-strip system detected various carbamates, including carbofuran, oxamyl, methomyl, and carbaryl, with limits of detection of 2, 21, 113, and 236 nM (S/N = 3), respectively. Furthermore, the fabricated biosensor exhibited good testing capabilities when used to detect carbamates added to various fruit and vegetable samples. - Highlights: • Acetylcholinesterase (AChE) dip-strip biosensor fabricated to detect carbamates. • AChE entrapped in fenugreek hydrogel–agarose matrix with gold nanoparticles (GNPs). • High enzyme retention efficiency (92%) and shelf life (half-life, 55 days). • Detection limits of carbofuran, oxamyl and methomyl: 2, 21 and 113 nM. • The biosensor had good testing capabilities to detect carbamates in food samples

  3. High throughput generation and trapping of individual agarose microgel using microfluidic approach

    KAUST Repository

    Shi, Yang

    2013-02-28

    Microgel is a kind of biocompatible polymeric material, which has been widely used as micro-carriers in materials synthesis, drug delivery and cell biology applications. However, high-throughput generation of individual microgel for on-site analysis in a microdevice still remains a challenge. Here, we presented a simple and stable droplet microfluidic system to realize high-throughput generation and trapping of individual agarose microgels based on the synergetic effect of surface tension and hydrodynamic forces in microchannels and used it for 3-D cell culture in real-time. The established system was mainly composed of droplet generators with flow focusing T-junction and a series of array individual trap structures. The whole process including the independent agarose microgel formation, immobilization in trapping array and gelation in situ via temperature cooling could be realized on the integrated microdevice completely. The performance of this system was demonstrated by successfully encapsulating and culturing adenoid cystic carcinoma (ACCM) cells in the gelated agarose microgels. This established approach is simple, easy to operate, which can not only generate the micro-carriers with different components in parallel, but also monitor the cell behavior in 3D matrix in real-time. It can also be extended for applications in the area of material synthesis and tissue engineering. © 2013 Springer-Verlag Berlin Heidelberg.

  4. Printing thermoresponsive reverse molds for the creation of patterned two-component hydrogels for 3D cell culture.

    Science.gov (United States)

    Müller, Michael; Becher, Jana; Schnabelrauch, Matthias; Zenobi-Wong, Marcy

    2013-01-01

    Bioprinting is an emerging technology that has its origins in the rapid prototyping industry. The different printing processes can be divided into contact bioprinting(1-4) (extrusion, dip pen and soft lithography), contactless bioprinting(5-7) (laser forward transfer, ink-jet deposition) and laser based techniques such as two photon photopolymerization(8). It can be used for many applications such as tissue engineering(9-13), biosensor microfabrication(14-16) and as a tool to answer basic biological questions such as influences of co-culturing of different cell types(17). Unlike common photolithographic or soft-lithographic methods, extrusion bioprinting has the advantage that it does not require a separate mask or stamp. Using CAD software, the design of the structure can quickly be changed and adjusted according to the requirements of the operator. This makes bioprinting more flexible than lithography-based approaches. Here we demonstrate the printing of a sacrificial mold to create a multi-material 3D structure using an array of pillars within a hydrogel as an example. These pillars could represent hollow structures for a vascular network or the tubes within a nerve guide conduit. The material chosen for the sacrificial mold was poloxamer 407, a thermoresponsive polymer with excellent printing properties which is liquid at 4 °C and a solid above its gelation temperature ~20 °C for 24.5% w/v solutions(18). This property allows the poloxamer-based sacrificial mold to be eluted on demand and has advantages over the slow dissolution of a solid material especially for narrow geometries. Poloxamer was printed on microscope glass slides to create the sacrificial mold. Agarose was pipetted into the mold and cooled until gelation. After elution of the poloxamer in ice cold water, the voids in the agarose mold were filled with alginate methacrylate spiked with FITC labeled fibrinogen. The filled voids were then cross-linked with UV and the construct was imaged with an

  5. Gating of Permanent Molds for ALuminum Casting

    Energy Technology Data Exchange (ETDEWEB)

    David Schwam; John F. Wallace; Tom Engle; Qingming Chang

    2004-03-30

    This report summarizes a two-year project, DE-FC07-01ID13983 that concerns the gating of aluminum castings in permanent molds. The main goal of the project is to improve the quality of aluminum castings produced in permanent molds. The approach taken was determine how the vertical type gating systems used for permanent mold castings can be designed to fill the mold cavity with a minimum of damage to the quality of the resulting casting. It is evident that somewhat different systems are preferred for different shapes and sizes of aluminum castings. The main problems caused by improper gating are entrained aluminum oxide films and entrapped gas. The project highlights the characteristic features of gating systems used in permanent mold aluminum foundries and recommends gating procedures designed to avoid common defects. The study also provides direct evidence on the filling pattern and heat flow behavior in permanent mold castings.

  6. NUMERICAL SIMULATION OF CASTING'S MOLD FILLING PROCESS

    Institute of Scientific and Technical Information of China (English)

    J.X. Zhou; R.X. Liu; L.L. Chen; D.M. Liao; H.S. Wei

    2005-01-01

    Numerical simulation of casting's mold filling process is the main and the most important aspect of the foundry CAE technology. But it is time-consuming; it may take dozens of hours or several days. While with the development of computer hardware, numerical simulation of casting' s mold filling process has made rapid progress. The simulation results, therefore, have become more and more practical. This study tries to find some clues of the computational time of mold filling process. Firstly, this paper introduces mathematic model and the basic route of numerical simulation of casting's mold filling process. Then the computational time of mold filling process has been carefully studied, and some new and useful results have been gained from the study of the computational time. Finally, this paper has given some real applications of numerical simulation of casting's mold filling process.

  7. Effect of Functional Nano Channel Structures Different Widths on Injection Molding and Compression Molding Replication Capabilities

    DEFF Research Database (Denmark)

    Calaon, M.; Tosello, G.; Garnaes, J.;

    The present study investigates the capabilities of the two employed processes, injection molding (IM) and injection compression molding (ICM) on replicating different channel cross sections. Statistical design of experiment was adopted to optimize replication quality of produced polymer parts wit...

  8. Porous media heat transfer for injection molding

    Energy Technology Data Exchange (ETDEWEB)

    Beer, Neil Reginald

    2016-05-31

    The cooling of injection molded plastic is targeted. Coolant flows into a porous medium disposed within an injection molding component via a porous medium inlet. The porous medium is thermally coupled to a mold cavity configured to receive injected liquid plastic. The porous medium beneficially allows for an increased rate of heat transfer from the injected liquid plastic to the coolant and provides additional structural support over a hollow cooling well. When the temperature of the injected liquid plastic falls below a solidifying temperature threshold, the molded component is ejected and collected.

  9. Indoor mold and Children's health

    Science.gov (United States)

    Etzel; Rylander

    1999-06-01

    Reactive airways disease in children is increasing in many countries around the world. The clinical diagnosis of asthma or reactive airways disease includes a variable airflow and an increased sensitivity in the airways. This condition can develop after an augmented reaction to a specific agent (allergen) and may cause a life-threatening situation within a very short period of exposure. It can also develop after a long-term exposure to irritating agents that cause an inflammation in the airways in the absence of an allergen. (paragraph) Several environmental agents have been shown to be associated with the increased incidence of childhood asthma. They include allergens, cat dander, outdoor as well as indoor air pollution, cooking fumes, and infections. There is, however, increasing evidence that mold growth indoors in damp buildings is an important risk factor. About 30 investigations from various countries around the world have demonstrated a close relationship between living in damp homes or homes with mold growth, and the extent of adverse respiratory symptoms in children. Some studies show a relation between dampness/mold and objective measures of lung function. Apart from airways symptoms, some studies demonstrate the presence of general symptoms that include fatigue and headache and symptoms from the central nervous system. At excessive exposures, an increased risk for hemorraghic pneumonia and death among infants has been reported. (paragraph) The described effects may have important consequences for children in the early years of life. A child's immune system is developing from birth to adolescence and requires a natural, physiologic stimulation with antigens as well as inflammatory agents. Any disturbances of this normal maturing process will increase the risk for abnormal reactions to inhaled antigens and inflammagenic agents in the environment. (paragraph) The knowledge about health risks due to mold exposure is not widespread and health authorities in

  10. Nonlinear Modeling of a High Precision Servo Injection Molding Machine Including Novel Molding Approach

    Institute of Scientific and Technical Information of China (English)

    何雪松; 王旭永; 冯正进; 章志新; 杨钦廉

    2003-01-01

    A nonlinear mathematical model of the injection molding process for electrohydraulic servo injection molding machine (IMM) is developed.It was found necessary to consider the characteristics of asymmetric cylinder for electrohydraulic servo IMM.The model is based on the dynamics of the machine including servo valve,asymmetric cylinder and screw,and the non-Newtonian flow behavior of polymer melt in injection molding is also considered.The performance of the model was evaluated based on novel approach of molding - injection and compress molding,and the results of simulation and experimental data demonstrate the effectiveness of the model.

  11. In vivo bioengineered ovarian tumors based on collagen, matrigel, alginate and agarose hydrogels: a comparative study

    International Nuclear Information System (INIS)

    Scaffold-based tumor engineering is rapidly evolving the study of cancer progression. However, the effects of scaffolds and environment on tumor formation have seldom been investigated. In this study, four types of injectable hydrogels, namely, collagen type I, Matrigel, alginate and agarose gels, were loaded with human ovarian cancer SKOV3 cells and then injected into nude mice subcutaneously. The growth of the tumors in vitro was also investigated. After four weeks, the specimens were harvested and analyzed. We found that tumor formation by SKOV3 cells was best supported by collagen, followed by Matrigel, alginate, control (without scaffold) and agarose in vivo. The collagen I group exhibited a larger tumor volume with increased neovascularization and increased necrosis compared with the other materials. Further, increased MMP activity, upregulated expression of laminin and fibronectin and higher levels of HIF-1α and VEGF-A in the collagen group revealed that the engineered tumor is closer to human ovarian carcinoma. In order, collagen, Matrigel, alginate, control (without scaffold) and agarose exhibited decreases in tumor formation. All evidence indicated that the in vivo engineered tumor is scaffold-dependent. Bioactive hydrogels are superior to inert hydrogels at promoting tumor regeneration. In particular, biomimetic hydrogels are advantageous because they provide a microenvironment that mimics the ECM of natural tumors. On the other hand, typical features of cancer cells and the expression of genes related to cancer malignancy were far less similar to the natural tumor in vitro, which indicated the importance of culture environment in vivo. Superior to the in vitro culture, nude mice can be considered satisfactory in vivo ‘bioreactors’ for the screening of favorable cell vehicles for tumor engineering in vitro. (paper)

  12. Acoustic transfer of protein crystals from agarose pedestals to micromeshes for high-throughput screening

    Energy Technology Data Exchange (ETDEWEB)

    Cuttitta, Christina M. [Brookhaven National Laboratory, Upton, NY 11973-5000 (United States); The City University of New York, 2800 Victory Boulevard, Staten Island, NY 10314 (United States); Ericson, Daniel L. [Brookhaven National Laboratory, Upton, NY 11973-5000 (United States); University at Buffalo, SUNY, 12 Capen Hall, Buffalo, NY 14260 (United States); Scalia, Alexander [Brookhaven National Laboratory, Upton, NY 11973-5000 (United States); Binghamton University, 4400 Vestal Parkway East, Binghamton, NY 11973-5000 (United States); Roessler, Christian G. [Brookhaven National Laboratory, Upton, NY 11973-5000 (United States); Teplitsky, Ella [Brookhaven National Laboratory, Upton, NY 11973-5000 (United States); Stony Brook University, Stony Brook, NY 11794-5215 (United States); Joshi, Karan [Brookhaven National Laboratory, Upton, NY 11973-5000 (United States); PEC University of Technology, Chandigarh (India); Campos, Olven [Brookhaven National Laboratory, Upton, NY 11973-5000 (United States); Florida Atlantic University, 777 Glades Road, Boca Raton, FL 33414 (United States); Agarwal, Rakhi; Allaire, Marc [Brookhaven National Laboratory, Upton, NY 11973-5000 (United States); Orville, Allen M. [Brookhaven National Laboratory, Upton, NY 11973-5000 (United States); Brookhaven National Laboratory, Upton, NY 11973-5000 (United States); Sweet, Robert M.; Soares, Alexei S., E-mail: soares@bnl.gov [Brookhaven National Laboratory, Upton, NY 11973-5000 (United States)

    2015-01-01

    An acoustic high-throughput screening method is described for harvesting protein crystals and combining the protein crystals with chemicals such as a fragment library. Acoustic droplet ejection (ADE) is an emerging technology with broad applications in serial crystallography such as growing, improving and manipulating protein crystals. One application of this technology is to gently transfer crystals onto MiTeGen micromeshes with minimal solvent. Once mounted on a micromesh, each crystal can be combined with different chemicals such as crystal-improving additives or a fragment library. Acoustic crystal mounting is fast (2.33 transfers s{sup −1}) and all transfers occur in a sealed environment that is in vapor equilibrium with the mother liquor. Here, a system is presented to retain crystals near the ejection point and away from the inaccessible dead volume at the bottom of the well by placing the crystals on a concave agarose pedestal (CAP) with the same chemical composition as the crystal mother liquor. The bowl-shaped CAP is impenetrable to crystals. Consequently, gravity will gently move the crystals into the optimal location for acoustic ejection. It is demonstrated that an agarose pedestal of this type is compatible with most commercially available crystallization conditions and that protein crystals are readily transferred from the agarose pedestal onto micromeshes with no loss in diffraction quality. It is also shown that crystals can be grown directly on CAPs, which avoids the need to transfer the crystals from the hanging drop to a CAP. This technology has been used to combine thermolysin and lysozyme crystals with an assortment of anomalously scattering heavy atoms. The results point towards a fast nanolitre method for crystal mounting and high-throughput screening.

  13. Mold

    Science.gov (United States)

    ... all, may produce toxins or poisonous substances called mycotoxins that may cause effects in humans. Although there are many types of mycotoxins, aflatoxins are probably the best known and most ...

  14. The preparation of low electroendosmosis agarose and its physico-chemical property

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Studies on Gelidium amansii agar fractionations were carried out in this paper. Gelidium amansii agar was fractionated on DEAE-Cellulose, and four fractions were obtained sequentially. The fractions were analyzed on physical and chemical properties, and IR and 13C-NMR spectroscopy applied for elucidating the chemical structure. Among the four fractions obtained, water fraction measured up to the standard of low EEO agarose. The sulfate content, ash content, electroendosmosis and gel strength(1%) of water fraction were 0.16%, 0.34%, 0.12 and 1 130g/cm2 respectively, similar to those of the Sigma products.

  15. Streptavidin Capture and Detection Using Individual Agarose Bead-based Microfluidic Immunoassay Devices

    Institute of Scientific and Technical Information of China (English)

    Xiaoguang Du

    2009-01-01

    @@ A single microwell on polycarbonate substratc was fabricated using hot embossing by silicon master.The silicon master (85 μm in top,100 μm in bottom,53 μm in height) and 0.25 mm-thick polycarbonate substrate were sandwiched between two glass plates in hot embossing system.The system was heated to 155-160℃ and pressed with a force of 300 psi for 10-30 s.The single microwell was stampted on polycarbonate substrate.Apply a~0.2 μL aliquot of agarose beads to the single microwell.

  16. Agarose gel investigation of quantum dots conjugated with short ssDNA.

    Science.gov (United States)

    Wu, Tsai-Chin; Dutta, Mitra; Stroscio, Michael A

    2013-12-01

    Herein, we investigate the migration distance of quantum-dot-functionalized complexes in electrophoresis. The quantitative study of these moving particles in an electrophoretic environment is modeled using an extended Smoluchowski equation. An extended Smoluchowski equation is proposed to addressed the D(m) to Ln(N) plot slope variation issue present in previous work and agreement between experiment and theory is found. The procedures underlying this work then discusses the potential of using agarose electrophoresis as a mean of monitoring the composition of nano-complexes consisting of quantum dots functionalized with differing numbers of DNA molecules.

  17. Dose response and fading characteristics of an alanine-agarose gel

    International Nuclear Information System (INIS)

    The dose response of an alanine-agarose gel, analyzed by ESR spectrometry, and the stability of the radiation-induced free radicals have been investigated. The stability of the ESR signal is higher for dosimeter samples analyzed at 77 K than for dried samples, analyzed at room-temperature. The dose response is linear to within ±2% in the absorbed dose interval 2-100 Gy. The variations in spectral line shape were analyzed at temperatures between 77 and 270 K. The experimental ESR spectrum at 77 K was compared with a simulated spectrum of polycrystals of L-α-alanine. (Author)

  18. Implementation of Molding Constraints in Topology Optimization

    DEFF Research Database (Denmark)

    Marx, S.; Kristensen, Anders Schmidt

    2009-01-01

    .e. uniform thickness, filling of the die and ejection of the molded item, i.e. extrusion. The mentioned injection mold parameters/factors are introduced in the topology optimization by defining a centerline of the initial domain and then penalize elements in respect to the distance to the defined centerline...

  19. Nanostructuring steel for injection molding tools

    DEFF Research Database (Denmark)

    Al-Azawi, A.; Smistrup, Kristian; Kristensen, Anders

    2014-01-01

    has been produced by injection molding with good structure transfer fidelity. Thus we have demonstrated that by utilizing well-established fabrication techniques, nanostructured steel shims that are used in injection molding, a technique that allows low cost mass fabrication of plastic items...

  20. Particle Image Velocimetry During Injection Molding

    Science.gov (United States)

    Bress, Thomas; Dowling, David

    2012-11-01

    Injection molding involves the unsteady non-isothermal flow of a non-Newtonian polymer melt. An optical-access mold has been used to perform particle image velocimetry (PIV) on molten polystyrene during injection molding. Velocimetry data of the mold-filling flow will be presented. Statistical assessments of the velocimetry data and scaled residuals of the continuity equation suggest that PIV can be conducted in molten plastics with an uncertainty of +/-2 percent. Simulations are often used to model polymer flow during injection molding to design molds and select processing parameters but it is difficult to determine the accuracy of these simulations due to a lack of in-mold velocimetry and melt-front progression data. Moldflow was used to simulate the filling of the optical-access mold, and these simulated results are compared to the appropriately-averaged time-varying velocity field measurements. Simulated results for melt-front progression are also compared with the experimentally observed flow fronts. The ratio of the experimentally measured average velocity magnitudes to the simulation magnitudes was found on average to be 0.99 with a standard deviation of 0.25, and the difference in velocity orientations was found to be 0.9 degree with a standard deviation of 3.2 degrees. formerly at the University of Michigan.

  1. Deadline Compliance Status Reports

    Data.gov (United States)

    Department of Housing and Urban Development — These monthly Deadline Compliance Status Reports assist Participating Jurisdictions and HUD Field Offices in monitoring compliance with the 2-year commitment and...

  2. Affordable, Precision Reflector Mold Technology (PDRT08-029) Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Advances in replication mold technology that reduce material costs, grinding time, and polishing time would enable fabrication of large, precision molds and...

  3. Mold Simulator Study of the Initial Solidification of Molten Steel in Continuous Casting Mold: Part II. Effects of Mold Oscillation and Mold Level Fluctuation

    Science.gov (United States)

    Zhang, Haihui; Wang, Wanlin

    2016-04-01

    The surface quality of the continuous casting strands is closely related to the initial solidification of liquid steel in the vicinity of the mold meniscus, and thus the clear understanding of the behavior of molten steel initial solidification would be of great importance for the control of the quality of final slab. With the development of the mold simulator techniques, the complex interrelationship between the solidified shell surface profile, heat flux, shell thickness, mold level fluctuation, and the infiltrated slag film was well illustrated in our previous study. As the second part, this article investigated the effect of the mold oscillation frequency, stroke, and mold level fluctuation on the initial solidification of the molten steel through the conduction of five different experiments. Results suggested that in the case of the stable mold level, the oscillation marks (OMs) exhibit equally spaced horizon depressions on the shell surface, where the heat flux at the meniscus area raises rapidly during negative strip time (NST) period and the presence of each OMs on the shell surface is corresponding to a peak value of the heat flux variation rate. Otherwise, the shell surface is poorly defined by the existence of wave-type defects, such as ripples or deep depressions, and the heat flux variation is irregular during NST period. The rising of the mold level leads to the longer-pitch and deeper OMs formation; conversely, the falling of mold level introduces shorter-pitch and shallower OMs. With the increase of the mold oscillation frequency, the average value of the low-frequency heat flux at the meniscus increases; however, it decreases when the mold oscillation stroke increases. Additionally, the variation amplitude of the high-frequency temperature and the high-frequency heat flux decreases with the increase of the oscillation frequency and the reduction of the oscillation stroke.

  4. Modification of a neuronal network direction using stepwise photo-thermal etching of an agarose architecture

    Directory of Open Access Journals (Sweden)

    Jimbo Yasuhiko

    2004-07-01

    Full Text Available Abstract Control over spatial distribution of individual neurons and the pattern of neural network provides an important tool for studying information processing pathways during neural network formation. Moreover, the knowledge of the direction of synaptic connections between cells in each neural network can provide detailed information on the relationship between the forward and feedback signaling. We have developed a method for topographical control of the direction of synaptic connections within a living neuronal network using a new type of individual-cell-based on-chip cell-cultivation system with an agarose microchamber array (AMCA. The advantages of this system include the possibility to control positions and number of cultured cells as well as flexible control of the direction of elongation of axons through stepwise melting of narrow grooves. Such micrometer-order microchannels are obtained by photo-thermal etching of agarose where a portion of the gel is melted with a 1064-nm infrared laser beam. Using this system, we created neural network from individual Rat hippocampal cells. We were able to control elongation of individual axons during cultivation (from cells contained within the AMCA by non-destructive stepwise photo-thermal etching. We have demonstrated the potential of our on-chip AMCA cell cultivation system for the controlled development of individual cell-based neural networks.

  5. Pravastatin Improves Glucose Regulation and Biocompatibility of Agarose Encapsulated Porcine Islets following Transplantation into Pancreatectomized Dogs

    Directory of Open Access Journals (Sweden)

    Lawrence S. Gazda

    2014-01-01

    Full Text Available The encapsulation of porcine islets is an attractive methodology for the treatment of Type I diabetes. In the current study, the use of pravastatin as a mild anti-inflammatory agent was investigated in pancreatectomized diabetic canines transplanted with porcine islets encapsulated in agarose-agarose macrobeads and given 80 mg/day of pravastatin (n=3 while control animals did not receive pravastatin (n=3. Control animals reached preimplant insulin requirements on days 18, 19, and 32. Pravastatin-treated animals reached preimplant insulin requirements on days 22, 27, and 50. Two animals from each group received a second macrobead implant: control animals remained insulin-free for 15 and 21 days (AUC = 3003 and 5078 mg/dL/24 hr days 1 to 15 and reached preimplant insulin requirements on days 62 and 131. Pravastatin treated animals remained insulin-free for 21 and 34 days (AUC = 1559 and 1903 mg/dL/24 hr days 1 to 15 and reached preimplant insulin requirements on days 38 and 192. Total incidence (83.3% versus 64.3% and total severity (22.7 versus 18.3 of inflammation on tissue surfaces were higher in the control group at necropsy. These findings support pravastatin therapy in conjunction with the transplantation of encapsulated xenogeneic islets for the treatment of diabetes mellitus.

  6. Dependence of light attenuation and backscattering on collagen concentration and chondrocyte density in agarose scaffolds

    Science.gov (United States)

    Puhakka, P. H.; Ylärinne, J. H.; Lammi, M. J.; Saarakkala, S.; Tiitu, V.; Kröger, H.; Virén, T.; Jurvelin, J. S.; Töyräs, J.

    2014-11-01

    Optical coherence tomography (OCT) has been applied for high resolution imaging of articular cartilage. However, the contribution of individual structural elements of cartilage on OCT signal has not been thoroughly studied. We hypothesize that both collagen and chondrocytes, essential structural components of cartilage, act as important light scatterers and that variation in their concentrations can be detected by OCT through changes in backscattering and attenuation. To evaluate this hypothesis, we established a controlled model system using agarose scaffolds embedded with variable collagen concentrations and chondrocyte densities. Using OCT, we measured the backscattering coefficient (µb) and total attenuation coefficient (µt) in these scaffolds. Along our hypothesis, light backscattering and attenuation in agarose were dependent on collagen concentration and chondrocyte density. Significant correlations were found between µt and chondrocyte density (ρ = 0.853, p collagen concentration (ρ = 0.694, p collagen concentration (ρ = 0.103, p = 0.422) of the scaffold. Thus, quantitation of light backscattering and, especially, attenuation could be valuable when evaluating the integrity of soft tissues, such as articular cartilage with OCT.

  7. Finite difference time domain model of ultrasound propagation in agarose scaffold containing collagen or chondrocytes.

    Science.gov (United States)

    Inkinen, Satu I; Liukkonen, Jukka; Malo, Markus K H; Virén, Tuomas; Jurvelin, Jukka S; Töyräs, Juha

    2016-07-01

    Measurement of ultrasound backscattering is a promising diagnostic technique for arthroscopic evaluation of articular cartilage. However, contribution of collagen and chondrocytes on ultrasound backscattering and speed of sound in cartilage is not fully understood and is experimentally difficult to study. Agarose hydrogels have been used in tissue engineering applications of cartilage. Therefore, the aim of this study was to simulate the propagation of high frequency ultrasound (40 MHz) in agarose scaffolds with varying concentrations of chondrocytes (1 to 32 × 10(6) cells/ml) and collagen (1.56-200 mg/ml) using transversely isotropic two-dimensional finite difference time domain method (FDTD). Backscatter and speed of sound were evaluated from the simulated pulse-echo and through transmission measurements, respectively. Ultrasound backscatter increased with increasing collagen and chondrocyte concentrations. Furthermore, speed of sound increased with increasing collagen concentration. However, this was not observed with increasing chondrocyte concentrations. The present study suggests that the FDTD method may have some applicability in simulations of ultrasound scattering and propagation in constructs containing collagen and chondrocytes. Findings of this study indicate the significant role of collagen and chondrocytes as ultrasound scatterers and can aid in development of modeling approaches for understanding how cartilage architecture affects to the propagation of high frequency ultrasound. PMID:27475127

  8. Simulated moving bed separation of agarose-hydrolyzate components for biofuel production from marine biomass.

    Science.gov (United States)

    Kim, Pung-Ho; Nam, Hee-Geun; Park, Chanhun; Wang, Nien-Hwa Linda; Chang, Yong Keun; Mun, Sungyong

    2015-08-01

    The economically-efficient separation of galactose, levulinic acid (LA), and 5-hydroxymethylfurfural (5-HMF) in acid hydrolyzate of agarose has been a key issue in the area of biofuel production from marine biomass. To address this issue, an optimal simulated moving bed (SMB) process for continuous separation of the three agarose-hydrolyzate components with high purities, high yields, and high throughput was developed in this study. As a first step for this task, the adsorption isotherm and mass-transfer parameters of each component on the qualified adsorbent were determined through a series of multiple frontal experiments. The determined parameters were then used in optimizing the SMB process for the considered separation. Finally, the optimized SMB process was tested experimentally using a self-assembled SMB unit with four zones. The SMB experimental results and the relevant computer simulations verified that the developed process in this study was quite successful in the economically-efficient separation of galactose, LA, and 5-HMF in a continuous mode with high purities and high yields. It is thus expected that the developed SMB process in this study will be able to serve as one of the trustworthy ways of improving the economic feasibility of biofuel production from marine biomass. PMID:26141276

  9. Cytoplasmic polyhedrosis virus classification by electropherotype; validation by serological analyses and agarose gel electrophoresis.

    Science.gov (United States)

    Mertens, P P; Crook, N E; Rubinstein, R; Pedley, S; Payne, C C

    1989-01-01

    Serological analyses of several different cytoplasmic polyhedrosis viruses (CPVs), including two type 1 CPVs from Bombyx mori, type 1 CPV from Dendrolimus spectabilis, type 12 CPV from Autographa gamma, type 2 CPV from Inachis io, type 5 CPV from Orgyia pseudotsugata and type 5 CPV from Heliothis armigera, demonstrated a close correlation between the antigenic properties of the polyhedrin or virus particle structural proteins and the genomic dsRNA electropherotypes. The dsRNAs of these viruses were analysed by electrophoresis in 3% and 10% polyacrylamide gels with a discontinuous Tris-HCl/Tris-glycine buffer system or by 1% agarose gel electrophoresis using a continuous Tris-acetate-EDTA buffer system. Electrophoretic analysis in agarose gels was found to be the most suitable for the classification of CPV isolates into electropherotypes, and the results obtained showed a close correlation with the observed antigenic relationships between different virus isolates. However, electrophoretic analysis in 10% polyacrylamide gels was most sensitive for the detection of intra-type variation and the presence of mixed virus isolates. PMID:2499658

  10. Poly-lactic acid and agarose gelatin play an active role in the recovery of spinal cord injury

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Objective To investigate the role of poly-lactic acid and agarose gelatin in promoting the functional recovery of the injured spinal cord. Methods Poly-lactic acid (PLA) or agarose was embedded in the space between two stumps of the hemisectioned spinal cord. Immunohistochemistry was used to show astroglia proliferation and the infiltration of RhoA-positive cells. Locomotor activity recovery was evaluated by testing the function of hindlimbs. Results Astroglias and RhoA labeled non-neuronal cells accumulated in the area adjacent to the implant, while the number of RhoA-positive cells was decreased dramatically in the absence of implant. Animals implanted with agarose gelatin recovered more quickly than those with PLA, concomitant with a higher survival rate of the neurons. Conclusion Both PLA and agarose gelatin benefited the recovery of spinal cord after injury by providing a scaffold for astroglia processes. Modulation of the rigidity, pore size and inner structure of PLA and agarose gelatin might make these biodegradable materials more effective in the regeneration of the central nervous system (CNS).

  11. Effect of the hydration on the biomechanical properties in a fibrin-agarose tissue-like model.

    Science.gov (United States)

    Scionti, Giuseppe; Moral, Monica; Toledano, Manuel; Osorio, Raquel; Durán, Juan D G; Alaminos, Miguel; Campos, Antonio; López-López, Modesto T

    2014-08-01

    The effect of hydration on the biomechanical properties of fibrin and fibrin-agarose (FA) tissue-like hydrogels is reported. Native hydrogels with approximately 99.5% of water content and hydrogels with water content reduced until 90% and 80% by means of plastic compression (nanostructuration) were generated. The biomechanical properties of the hydrogels were investigated by tensile, compressive, and shear tests. Experimental results indicate that nanostructuration enhances the biomechanical properties of the hydrogels. This improvement is due to the partial draining of the water that fills the porous network of fibers that the plastic compression generates, which produces a denser material, as confirmed by scanning electron microscopy. Results also indicate that the characteristic compressive and shear parameters increase with agarose concentration, very likely due to the high water holding capacity of agarose, which reduces the compressibility and gives consistency to the hydrogels. However, results of tensile tests indicate a weakening of the hydrogels as agarose concentration increases, which evidences the anisotropic nature of these biomaterials. Interestingly, we found that by adjusting the water and agarose contents it is possible to tune the biomechanical properties of FA hydrogels for a broad range, within which the properties of many native tissues fall. PMID:23963645

  12. Thermoplastic blow molding of metals

    Directory of Open Access Journals (Sweden)

    Jan Schroers

    2011-01-01

    Full Text Available While plastics have revolutionized industrial design due to their versatile processability, their relatively low strength has hampered their use in structural components. On the other hand, while metals are the basis for strong structural components, the geometries into which they can be processed are rather limited. The “ideal” material would offer a desirable combination of superior structural properties and the ability to be precision (net shaped into complex geometries. Here we show that bulk metallic glasses (BMGs, which have superior mechanical properties, can be blow molded like plastics. The key to the enhanced processability of BMG formers is their amenability to thermoplastic forming. This allows complex BMG structures, some of which cannot be produced using any other metal process, to be net shaped precisely.

  13. Characterization of fiberglass-filled diallyl phthalate plastic molding resins and molded parts

    Energy Technology Data Exchange (ETDEWEB)

    Whitaker, R.B.; Glaub, J.E.; Bonekowski, N.R.; Gillham, P.D.

    1980-12-01

    Characterization of diallyl phthalate (DAP) molding resins was undertaken by differential scanning calorimetry (DSC) and by combined size exclusion chromatography (SEC)/low angle laser light scattering (LALLS) in order to better predict moldability and storage life limits. Completeness of cure of molded parts, before and after any post-curing, was also determined by thermal analysis. Molecular weights and molecular weight distributions of the DAP molding resins by SEC/LALLS indicated that the better molding resins have lower M/sub w//M/sub n/ ratios. Association effects were observed, which could not be overcome by solvent modification alone. Determination of DAP molding resin heats of reaction by DSC indicated a linear relation between ..delta..H/sub R/ and weight percent filler for the good molding resins. DSC analyses of molded DAP parts showed that 95% cure was achieved in some as-molded parts, with a post-cure temperature of 165/sup 0/C being required to complete the cure to 100%. Thickness of the parts was a factor, with the thicker parts being 100% cured as molded. The glass transition temperature (T/sub g/) of the molded parts increased as cure was completed, to approx. 160 to 165/sup 0/C maximum. These results are consistent with a model of thermoset resin curing behavior which states that 100% cure can be achieved only if a post-curing operation is conducted above the T/sub g infinity/ (T/sub g/ at complete cure) of the polymer.

  14. Residual stresses in injection molded products

    Science.gov (United States)

    Jansen, K. M. B.

    2015-12-01

    During the molding process residual stresses are formed due to thermal contraction during cooling as well as the local pressure history during solidification. In this paper a simple analytical model is reviewed which relates residual stresses, product shrinkage as well as warpage to the temperature and pressure histories during molding. Precise excimer laser layer removal measurements were performed to verify the predicted residual stress distributions. In addition, detailed shrinkage and warpage measurements on a large series of polymers and for different molding conditions were performed and are shown to compare well with the model predictions.

  15. Cooling simulation of plastic injection molding

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Analyses the cooling of mold and plastic part during injectionmolding and the continued cooling of plastic part after being ejected from mold using the heat transfer theory and Boundary Element Method (BEM) to predict the temperature distribution in both mold and plastic part,and presents the experiments carried out with plates of ABS (Acrylonitrile-Butadiene-Styrene) to verify the validity of the cooling analysis software used to simulate the temperature distribution in ABS plate parts, and concludes that the analysis software agree qualitatively well with actual experimental findings.

  16. Slimeware: engineering devices with slime mold.

    Science.gov (United States)

    Adamatzky, Andrew

    2013-01-01

    The plasmodium of the acellular slime mold Physarum polycephalum is a gigantic single cell visible to the unaided eye. The cell shows a rich spectrum of behavioral patterns in response to environmental conditions. In a series of simple experiments we demonstrate how to make computing, sensing, and actuating devices from the slime mold. We show how to program living slime mold machines by configurations of repelling and attracting gradients and demonstrate the workability of the living machines on tasks of computational geometry, logic, and arithmetic. PMID:23834592

  17. Application of MoldFlow in injection molding%MoldFlow在注塑成型中的应用

    Institute of Scientific and Technical Information of China (English)

    汤宏群; 苏广才

    2003-01-01

    利用MoldFlow对星型注塑件不同浇口位置进行流动模拟分析,预测可能存在的气泡位置和熔接痕位置,确定最佳浇口位置和数目.以此为例说明MoldFlow在注塑成型中应用的好处.

  18. The effect of mold surface topography on plastic parat in-process shrinkage in injection molding

    DEFF Research Database (Denmark)

    Arlø, Uffe Rolf; Hansen, Hans Nørgaard; Kjær, Erik Michael

    2003-01-01

    An experimental study of the effect of mold surface roughness on in-process in-flow linear part shrinkage in injection molding has been carried out. The investigation is based on an experimental two-cavity tool, where the cavities have different surface topographies, but are otherwise identical....... The study has been carried out for typical commercial polystyrene and polypropylene grades. The relationship between mold surface topography and linear shrinkage has been investigated with an experimental two-cavity mold producing simple rectangular parts with the nominal dimensions 1 x 25 x 50 mm...

  19. A new insight into foaming mechanisms in injection molding via a novel visualization mold

    Directory of Open Access Journals (Sweden)

    V. Shaayegan

    2016-06-01

    Full Text Available The complex mechanisms of bubble nucleation and dynamics in foam injection molding have not been uncovered despite many previous efforts due to the non-steady stop-and-flow nature of injection molding and the non-uniform temperature and pressure distributions in the mold. To this end, a new visualization mold was designed and manufactured for the direct observation of bubble nucleation and growth/collapse in foam injection molding. A reflective prism was incorporated into the stationary part of the injection mold with which the nucleation and growth behaviors of bubbles were successfully observed. The mechanisms of bubble nucleation in low- and high-pressure foam injection molding, with and without the application of gas-counter pressure, was investigated. We identified how the inherently non-uniform cell structure is developed in low-pressure foam injection molding with gate-nucleated bubbles, and when and how cell nucleation occurs in high-pressure foam injection molding with a more uniform pressure drop.

  20. Rozen : steeds meer bekend over Black Mold

    NARCIS (Netherlands)

    Smits, A.P.; Kohrman, E.

    2009-01-01

    Onderzoek naar Black Mold heeft al veel informatie opgeleverd over de verspreiding, bestrijding en ontwikkeling van de oculatieschimmel. In dit artikel de nieuwste resultaten van PPO en Cultus Agro Advies

  1. Kinetic model for whey protein hydrolysis by alcalase multipoint-immobilized on agarose gel particles

    Directory of Open Access Journals (Sweden)

    Sousa Jr R.

    2004-01-01

    Full Text Available Partial hydrolysis of whey proteins by enzymes immobilized on an inert support can either change or evidence functional properties of the produced peptides, thereby increasing their applications. The hydrolysis of sweet cheese whey proteins by alcalase, which is multipoint-immobilized on agarose gel, is studied here. A Michaelis-Menten model that takes into account competitive inhibition by the product was fitted to experimental data. The influence of pH on the kinetic parameters in the range 6.0 to 11.0 was assessed, at 50ºC. Initial reaction-rate assays in a pHstat at different concentrations of substrate were used to estimate kinetic and Michaelis-Menten parameters, k and K M. Experimental data from long-term batch assays were used to quantify the inhibition parameter, K I. The fitting of the model to the experimental data was accurate in the entire pH range.

  2. Hydrolysis of chickpea proteins with Flavourzyme immobilized on glyoxyl-agarose gels improves functional properties.

    Science.gov (United States)

    del Mar Yust, María; del Carmen Millán-Linares, María; Alcaide-Hidalgo, Juan María; Millán, Francisco; Pedroche, Justo

    2013-06-01

    Chickpea protein isolate was hydrolyzed using Flavourzyme immobilized on glyoxyl-agarose beads by multipoint covalent attachment. This Flavourzyme-glyoxyl derivative, produced after 1 h of immobilization at 4 °C followed by 5.5 h at room temperature, presented approximately 51% of the endoprotease activity of Flavourzyme but was around 700 times more stable than soluble enzyme. Chickpea protein hydrolysates ranging from 1% to 10% degree of hydrolysis were produced and their chemical composition was very close to that of protein isolate used as starting material. Solubility, oil absorption, emulsifying activity and stability, and foaming capacity and stability were determined. All protein hydrolysates showed higher solubility than intact proteins, especially at pHs near isoelectric point of native chickpea proteins. Moreover, all hydrolysates had better functional properties, except emulsifying activity, than the original protein isolate.

  3. Fricke-agarose dosimeter gels: ion diffusion modelling and microdensitometry alternative to MRI

    International Nuclear Information System (INIS)

    Ferric ion diffusion is one of the main problems that still restrains the dosimetric application of Fricke-agarose gels. In this work, we model this process within finite length gel samples. The temporal evolution of the ion concentration as a function of the initial concentration is derived by solving Fick's second law in two dimensions with boundary reflections. The influence of ion concentration gradient, elapsed time, diffusion coefficient and spatial resolution is studied. Due to the main drawbacks of MRI for studying these systems, i.e. high cost and acquisition time often non-negligible compared to diffusion time, we also investigate the possibility of using a microdensitometer. The application of this technique for Fricke gel dosimetry is proposed here for the first time. The estimate of the ion diffusion coefficient is in a very agreement with those reported in literature

  4. Die Casting Mold Design for Aluminum Alloy Shell of Instrument

    Directory of Open Access Journals (Sweden)

    Li Yuanyuan

    2015-01-01

    Full Text Available This paper is about die casting mold design for aluminum alloy shell of instrument. Three-dimensional model of the casting and mold are designed by using Pro/Engineer and AutoCad which can analyze forming quality. Digital design and theoretical calculation can greatly shorten product development cycle and mold design cycle, improve the accuracy of product design and mold design, and reduce the cost of mold design.

  5. Tool steel quality and surface finishing of plastic molds

    OpenAIRE

    Rafael Agnelli Mesquita; Reinhold Schneider

    2010-01-01

    Plastic industry is today in a constant growth, demanding several products from other segments, which includes the plastic molds, mainly used in the injection molding process. Considering all the requirements of plastic molds, the surface finishing is of special interest, as the injected plastic part is able to reproduce any details (and also defects) from the mold surface. Therefore, several aspects on mold finishing are important, mainly related to manufacturing conditions - machining, grin...

  6. Comparison of several closure approximations for evaluating the thermoelastic properties of an injection molded short-fiber composite

    OpenAIRE

    DRAY, Delphine; Gilormini, Pierre; Regnier, Gilles

    2007-01-01

    The accurate prediction of both the elastic properties and the thermal expansion coefficients is very important for the precise simulation of such processes as injection molding of short-fiber polymer-matrix composites. In this work, a two-step homogenization procedure is applied and compared with experimental values obtained on a polyarylamide/glass fiber composite for a broad range of temperatures. It is observed that the stiffness averaging version of the model surpasses the compliance ave...

  7. Polyamide 6 - long glass fiber injection moldings

    OpenAIRE

    Bijsterbosch, H.; Gaymans, R.J.

    1995-01-01

    The injection molding ability of long glass fiber reinforced polyamide pellets was studied. The injection moldable materials were produced by a melt impregnation process of continuous fiber rovings. The rovings were chopped to pellets of 9 mm length. Chopped pellets with a variation in the degree of impregnation and fiber concentration were studied. The injection molded samples were analyzed for fiber concentration, fiber length, and fiber orientation. Dumbbell-shaped tensile bars were made t...

  8. FACTORS ON VISCOSITY STABILITY OF MOLD FLUXES

    Institute of Scientific and Technical Information of China (English)

    C.Y.Zhu; C.J.Liu; M.F.Jiang; Z.D.Yang

    2004-01-01

    Viscosity stability indexes of mold flux at high temperature and low temperature have been introduced,and the effects of flux compositions on viscosity stability indexes have been studied.Two mold fluxes have been developed by analyzing the effects of flux viscosity stability on the process and the condition of continuous casting slab of medium carbon steel.The results show that the fluxes are suitable for the process.

  9. Mapping Tax Compliance

    DEFF Research Database (Denmark)

    Boll, Karen

    2014-01-01

    Tax compliance denotes the act of reporting and paying taxes in accordance with the tax laws. Current social science scholarship on tax compliance can almost entirely be divided into behavioural psychology analyses and critical tax studies. This article, which presents two cases of how tax...... compliance is constructed, challenges the explanatory reaches of today's social science approaches, arguing that an alternative approach to understanding tax compliance is worthwhile exploring. This other choice of approach, inspired by actor–network theory (ANT), adopts a more practice-oriented focus...... that studies tax compliance where it takes place as well as what it is made of. Consequently, this article argues that tax compliance is a socio-material assemblage and that complying is a distributed action. The article concludes by highlighting how an ANT approach contributes to the further theoretical...

  10. EFFECTIVENESS OF CELLULAR INJECTION MOLDING PROCESS

    Directory of Open Access Journals (Sweden)

    Tomasz Garbacz

    2013-06-01

    Full Text Available In a study of cellular injection, molding process uses polyvinylchloride PVC. Polymers modified with introducing blowing agents into them in the Laboratory of the Department of Technologies and Materiase of Technical University of Kosice. For technological reasons, blowing agents have a form of granules. In the experiment, the content of the blowing agent (0–2,0 % by mass fed into the processed polymer was adopted as a variable factor. In the studies presented in the article, the chemical blowing agents occurring in the granulated form with a diameter of 1.2 to 1.4 mm were used. The view of the technological line for cellular injection molding and injection mold cavity with injection moldings are shown in Figure 1. The results of the determination of selected properties of injection molded parts for various polymeric materials, obtained with different content of blowing agents, are shown in Figures 4-7. Microscopic examination of cross-sectional structure of the moldings were obtained using the author's position image analysis of porous structure. Based on analysis of photographs taken (Figures 7, 8, 9 it was found that the coating containing 1.0% of blowing agents is a clearly visible solid outer layer and uniform distribution of pores and their sizes are similar.

  11. The MOLD expert of VAI - A mold monitoring system for best casting performance

    International Nuclear Information System (INIS)

    The increasing demand for higher quality products of the clients each year needs a better understanding of the continuous casting process to fulfill also in the future these requirements to be competitive on the steel market. Based on these strong economic boundary conditions the VAI MOLD EXPERT is able to cover these requirements. The VAI's MOLD EXPERT enables deep insight into the process behavior of the mold package and will be used in an advanced stage to partly control the casting machine with the goal of stable operation and high quality product. In the first step the MOLD EXPERT is a tool to acquire, store, compress and visualize measurement data of the mold/oscillator, with the advantage of gathering all data in one system. In the second step, these data are interpreted via mathematical models which are linked together to make comparisons to adaptive limits and setpoints. The benefit of the MOLD EXPERT is manifold. For the metallurgists new insight into the continuous casting process are given which results in a better interpretation of the whole casting process. New casting practices and alarm limits will be derived from the MOLD EXPERT. These results will increase the operational process stability and the product quality continuously. For the operators an on-line visualization is available to get a better support and to cast permanently with the optimal parameters. The modular hard- and software concept of MOLD EXPERT is shown and the different packages - mold thermic, mold oscillation, casting powder, mold level, steel flow, narrowface taper - including visualization monitors will be described in detail. (author)

  12. Ag@AgI, core@shell structure in agarose matrix as hybrid: synthesis, characterization, and antimicrobial activity.

    Science.gov (United States)

    Ghosh, Somnath; Saraswathi, A; Indi, S S; Hoti, S L; Vasan, H N

    2012-06-01

    A novel in situ core@shell structure consisting of nanoparticles of Ag (Ag Nps) and AgI in agarose matrix (Ag@AgI/agarose) has been synthesized as a hybrid, in order to have an efficient antibacterial agent for repetitive usage with no toxicity. The synthesized core@shell structure is very well characterized by XRD, UV-visible, photoluminescence, and TEM. A detailed antibacterial studies including repetitive cycles are carried out on Gram-negative Escherichia coli (E. coli) and Gram-positive Staphylococcus aureus (S. aureus) bacteria in saline water, both in dark and on exposure to visible light. The hybrid could be recycled for the antibacterial activity and is nontoxic toward human cervical cancer cells (HeLa cells). The water insoluble Ag@AgI in agarose matrix forms a good coating on quartz, having good mechanical strength. EPR and TEM studies are carried out on the Ag@AgI/agarose and the bacteria, respectively, to elucidate a possible mechanism for killing of the bacteria. PMID:22582868

  13. No Evidence of Viral Transmission following Long-Term Implantation of Agarose Encapsulated Porcine Islets in Diabetic Dogs

    Directory of Open Access Journals (Sweden)

    Lawrence S. Gazda

    2014-01-01

    Full Text Available We have previously described the use of a double coated agarose-agarose porcine islet macrobead for the treatment of type I diabetes mellitus. In the current study, the long-term viral safety of macrobead implantation into pancreatectomized diabetic dogs treated with pravastatin (n=3 was assessed while 2 dogs served as nonimplanted controls. A more gradual return to preimplant insulin requirements occurred after a 2nd implant procedure (days 148, 189, and >652 when compared to a first macrobead implantation (days 9, 21, and 21 in all macrobead implanted animals. In all three implanted dogs, porcine C-peptide was detected in the blood for at least 10 days following the first implant and for at least 26 days following the second implant. C-peptide was also present in the peritoneal fluid of all three implanted dogs at 6 months after 2nd implant and in 2 of 3 dogs at necropsy. Prescreening results of islet macrobeads and culture media prior to transplantation were negative for 13 viruses. No evidence of PERV or other viral transmission was found throughout the study. This study demonstrates that the long-term (2.4 years implantation of agarose-agarose encapsulated porcine islets is a safe procedure in a large animal model of type I diabetes mellitus.

  14. Gating of Permanent Molds for Aluminum Casting

    Energy Technology Data Exchange (ETDEWEB)

    David Schwam; John F. Wallace; Tom Engle; Qingming Chang

    2004-01-01

    This report summarizes a two-year project, DE-FC07-011D13983 that concerns the gating of aluminum castings in permanent molds. The main goal of the project is to improve the quality of aluminum castings produced in permanent molds. The approach taken was to determine how the vertical type gating systems used for permanent mold castings can be designed to fill the mold cavity with a minimum of damage to the quality of the resulting casting. It is evident that somewhat different systems are preferred for different shapes and sizes of aluminum castings. The main problems caused by improper gating are entrained aluminum oxide films and entrapped gas. The project highlights the characteristic features of gating systems used in permanent mold aluminum foundries and recommends gating procedures designed to avoid common defects. The study also provides direct evidence on the filling pattern and heat flow behavior in permanent mold castings. Equipment and procedure for real time X-Ray radiography of molten aluminum flow into permanent molds have been developed. Other studies have been conducted using water flow and behavior of liquid aluminum in sand mold using real time photography. This investigation utilizes graphite molds transparent to X-Rays making it possible to observe the flow pattern through a number of vertically oriented grating systems. These have included systems that are choked at the base of a rounded vertical sprue and vertical gating systems with a variety of different ingates into the bottom of a mold cavity. These systems have also been changed to include gating systems with vertical and horizontal gate configurations. Several conclusions can be derived from this study. A sprue-well, as designed in these experiments, does not eliminate the vena contracta. Because of the swirling at the sprue-base, the circulating metal begins to push the entering metal stream toward the open runner mitigating the intended effect of the sprue-well. Improved designs of

  15. Rapid control of mold temperature during injection molding process: Effect of packing pressure

    Science.gov (United States)

    Liparoti, Sara; Sorrentino, Andrea; Titomanlio, Giuseppe

    2015-12-01

    A thorough analysis of the effect of operative conditions of injection molding process on the morphology distribution inside the obtained molded is performed, with particular reference to semi- crystalline polymers. In particular, fully characterized injection molding tests are presented using an isotactic polypropylene, previously carefully characterized as far as most of properties of interest. The effects of mold temperature and packing conditions are analyzed. The mold temperature was controlled by a thin heating device, composed by polyimide as insulating layer and polyimide loaded carbon black as electrical conductive layer, that is able to increase temperature on mold surface in few seconds (70°C/s) by joule effect and cool down soon after. The shear layer thickness in the molded is reduced in the samples produced at high mold temperatures, that means high electrical power and long heating time, and this reduction is more significant at lower packing pressures, indeed, at 360bar as packing pressure and 20s as heating time the shear layer disappear. The resulting morphology was analyzed by optical microscope.

  16. Fast Mold Temperature Evolution on Micro Features Replication Quality during Injection Molding

    DEFF Research Database (Denmark)

    Liparoti, S.; Calaon, Matteo; Speranza, V.;

    2016-01-01

    lithography and subsequent nickel electroplating. The mold temperature was controlled by a thin heating device (composed by polyimide as insulating layer and polyimide carbon black loaded aselectrical conductive layer) able to increase the temperature on mold surface in a few seconds (40°C/s) by Joule effect...

  17. Tuning mechanical performance of poly(ethylene glycol) and agarose interpenetrating network hydrogels for cartilage tissue engineering.

    Science.gov (United States)

    Rennerfeldt, Deena A; Renth, Amanda N; Talata, Zsolt; Gehrke, Stevin H; Detamore, Michael S

    2013-11-01

    Hydrogels are attractive for tissue engineering applications due to their incredible versatility, but they can be limited in cartilage tissue engineering applications due to inadequate mechanical performance. In an effort to address this limitation, our team previously reported the drastic improvement in the mechanical performance of interpenetrating networks (IPNs) of poly(ethylene glycol) diacrylate (PEG-DA) and agarose relative to pure PEG-DA and agarose networks. The goal of the current study was specifically to determine the relative importance of PEG-DA concentration, agarose concentration, and PEG-DA molecular weight in controlling mechanical performance, swelling characteristics, and network parameters. IPNs consistently had compressive and shear moduli greater than the additive sum of either single network when compared to pure PEG-DA gels with a similar PEG-DA content. IPNs withstood a maximum stress of up to 4.0 MPa in unconfined compression, with increased PEG-DA molecular weight being the greatest contributing factor to improved failure properties. However, aside from failure properties, PEG-DA concentration was the most influential factor for the large majority of properties. Increasing the agarose and PEG-DA concentrations as well as the PEG-DA molecular weight of agarose/PEG-DA IPNs and pure PEG-DA gels improved moduli and maximum stresses by as much as an order of magnitude or greater compared to pure PEG-DA gels in our previous studies. Although the viability of encapsulated chondrocytes was not significantly affected by IPN formulation, glycosaminoglycan (GAG) content was significantly influenced, with a 12-fold increase over a three-week period in gels with a lower PEG-DA concentration. These results suggest that mechanical performance of IPNs may be tuned with partial but not complete independence from biological performance of encapsulated cells.

  18. Mathematical modeling of the process of filling a mold during injection molding of ceramic products

    Science.gov (United States)

    Kulkov, S. N.; Korobenkov, M. V.; Bragin, N. A.

    2015-10-01

    Using the software package Fluent it have been predicted of the filling of a mold in injection molding of ceramic products is of great importance, because the strength of the final product is directly related to the presence of voids in the molding, making possible early prediction of inaccuracies in the mold prior to manufacturing. The calculations were performed in the formulation of mathematical modeling of hydrodynamic turbulent process of filling a predetermined volume of a viscous liquid. The model used to determine the filling forms evaluated the influence of density and viscosity of the feedstock, and the injection pressure on the mold filling process to predict the formation of voids in the area caused by the shape defect geometry.

  19. Effects of mold geometry on fiber orientation of powder injection molded metal matrix composites

    Energy Technology Data Exchange (ETDEWEB)

    Ahmad, Faiz, E-mail: faizahmad@petronas.com.my; Aslam, Muhammad, E-mail: klaira73@gmail.com; Altaf, Khurram, E-mail: khurram.altaf@petronas.com.my; Shirazi, Irfan, E-mail: irfanshirazi@hotmail.com [Mechanical Engineering Universiti Teknologi PETRONAS Malaysia (Malaysia)

    2015-07-22

    Fiber orientations in metal matrix composites have significant effect on improving tensile properties. Control of fiber orientations in metal injection molded metal composites is a difficult task. In this study, two mold cavities of dimensions 6x6x90 mm and 10x20x180 mm were used for comparison of fiber orientation in injection molded metal composites test parts. In both mold cavities, convergent and divergent flows were developed by modifying the sprue dimensions. Scanning electron microscope (SEM) was used to examine the fiber orientations within the test samples. The results showed highly aligned fiber in injection molded test bars developed from the convergent melt flow. Random orientation of fibers was noted in the composites test bars produced from divergent melt flow.

  20. Injection molding simulation with variothermal mold temperature control of highly filled polyphenylene sulfide

    Science.gov (United States)

    Birkholz, A.; Tschiersky, M.; Wortberg, J.

    2015-05-01

    For the installation of a fuel cell stack to convert chemical energy into electricity it is common to apply bipolar plates to separate and distribute reaction gases and cooling agents. For reducing manufacturing costs of bipolar plates a fully automated injection molding process is examined. The high performance thermoplastic matrix material, polyphenylene sulfide (PPS), defies against the chemical setting and the operation temperature up to 200 °C. To adjust also high electrical and thermal conductivity, PPS is highly filled with various carbon fillers up to an amount of 65 percentage by volume. In the first step two different structural plates (one-sided) with three different gate heights and molds are designed according to the characteristics of a bipolar plate. To cope with the approach that this plate should be producible on standard injection molding machines with variothermal mold temperature control, injection molding simulation is used. Additionally, the simulation should allow to formulate a quality prediction model, which is transferrable to bipolar plates. Obviously, the basis for a precise simulation output is an accurate description of the material properties and behavior of the highly filled compound. This, the design of the structural plate and mold and the optimization via simulation is presented, as well. The influence of the injection molding process parameters, e.g. injection time, cycle times, packing pressure, mold temperature, and melt temperature on the form filling have been simulated to determine optimal process conditions. With the aid of the simulation and the variothermal mold temperature control it was possible to reduce the required melt temperature below the decomposition temperature of PPS. Thereby, hazardous decomposition products as hydrogen sulfide are obviated. Thus, the health of the processor, the longevity of the injection molding machine as well as the material and product properties can be protected.

  1. Powder Injection Molding of Titanium Components

    Energy Technology Data Exchange (ETDEWEB)

    Simmons, Kevin L.; Nyberg, Eric A.; Weil, K. Scott; Miller, Megan R.

    2005-01-01

    Powder injection molding (PIM) is a well-established, cost-effective method of fabricating small-to-moderate size metal components. Derived from plastic injection molding and employing a mixture of metal powder and plastic binder, the process has been used with great success in manufacturing a wide variety of metal products, including those made from stainless steel, nickel-based superalloys, and copper alloys. Less progress has been achieved with titanium and other refractory metal alloys because of problems with alloy impurities that are directly attributable to the injection molding process. Specifically, carbon, oxygen, and nitrogen are left behind during binder removal and become incorporated into the chemistry and microstructure of the material during densification. Even at low concentration, these impurities can cause severe degradation in the mechanical properties of titanium and its alloys. We have developed a unique blend of PIM constituents where only a small volume fraction of binder (~5 – 10 vol%) is required for injection molding; the remainder of the mixture consists of the metal powder and binder solvent. Because of the nature of decomposition in the binder system and the relatively small amount used, the binder is eliminated almost completely from the pre-sintered component during the initial stage of a two-step heat treatment process. Results will be presented on the first phase of this research, in which the binder, injection molding, de-binding and sintering schedule were developed. Additional data on the mechanical and physical properties of the material produced will be discussed.

  2. Nanostructuring steel for injection molding tools

    International Nuclear Information System (INIS)

    The production of nanostructured plastic items by injection molding with ridges down to 400 nm in width, which is the smallest line width replicated from nanostructured steel shims, is presented. Here we detail a micro-fabrication method where electron beam lithography, nano-imprint lithography and ion beam etching are combined to nanostructure the planar surface of a steel wafer. Injection molded plastic parts with enhanced surface properties, like anti-reflective, superhydrophobic and structural colors can be achieved by micro- and nanostructuring the surface of the steel molds. We investigate the minimum line width that can be realized by our fabrication method and the influence of etching angle on the structure profile during the ion beam etching process. Trenches down to 400 nm in width have been successfully fabricated into a 316 type electro-polished steel wafer. Afterward a plastic replica has been produced by injection molding with good structure transfer fidelity. Thus we have demonstrated that by utilizing well-established fabrication techniques, nanostructured steel shims that are used in injection molding, a technique that allows low cost mass fabrication of plastic items, are produced. (paper)

  3. Double blind placebo controlled exposure to molds

    DEFF Research Database (Denmark)

    Meyer, H W; Jensen, K A; Nielsen, K F;

    2005-01-01

    The objective was to develop an experimental setup for human exposure to mold spores, and to study the clinical effect of this exposure in sensitive subjects who had previously experienced potentially building-related symptoms (BRS) at work. From three water-damaged schools eight employees....... In conclusion this is, to our knowledge, the first study to successfully conduct a human exposure to a highly controlled dose of fungal material aerosolized directly from wet building materials. This short-term exposure to high concentrations of two different molds induced no more reactions than exposure...... to placebo in eight sensitive school employees. However, a statistical type II error cannot be excluded because of the small sample size. PRACTICAL IMPLICATIONS: In this double blind, placebo controlled study of mold exposure changes in symptoms, objective measurements and blood samples were small and mostly...

  4. Single gate optimization for plastic injection mold

    Institute of Scientific and Technical Information of China (English)

    LI Ji-quan; LI De-qun; GUO Zhi-ying; LV Hai-yuan

    2007-01-01

    This paper deals with a methodology for single gate location optimization for plastic injection mold. The objective of the gate optimization is to minimize the warpage of injection molded parts, because warpage is a crucial quality issue for most injection molded parts while it is influenced greatly by the gate location. Feature warpage is defined as the ratio of maximum displacement on the feature surface to the projected length of the feature surface to describe part warpage. The optimization is combined with the numerical simulation technology to find the optimal gate location, in which the simulated annealing algorithm is used to search for the optimum. Finally, an example is discussed in the paper and it can be concluded that the proposed method is effective.

  5. High rate fabrication of compression molded components

    Energy Technology Data Exchange (ETDEWEB)

    Matsen, Marc R.; Negley, Mark A.; Dykstra, William C.; Smith, Glen L.; Miller, Robert J.

    2016-04-19

    A method for fabricating a thermoplastic composite component comprises inductively heating a thermoplastic pre-form with a first induction coil by inducing current to flow in susceptor wires disposed throughout the pre-form, inductively heating smart susceptors in a molding tool to a leveling temperature with a second induction coil by applying a high-strength magnetic field having a magnetic flux that passes through surfaces of the smart susceptors, shaping the magnetic flux that passes through surfaces of the smart susceptors to flow substantially parallel to a molding surface of the smart susceptors, placing the heated pre-form between the heated smart susceptors; and applying molding pressure to the pre-form to form the composite component.

  6. Neonatal Ear Molding: Timing and Technique.

    Science.gov (United States)

    Anstadt, Erin Elizabeth; Johns, Dana Nicole; Kwok, Alvin Chi-Ming; Siddiqi, Faizi; Gociman, Barbu

    2016-03-01

    The incidence of auricular deformities is believed to be ∼11.5 per 10,000 births, excluding children with microtia. Although not life-threatening, auricular deformities can cause undue distress for patients and their families. Although surgical procedures have traditionally been used to reconstruct congenital auricular deformities, ear molding has been gaining acceptance as an efficacious, noninvasive alternative for the treatment of newborns with ear deformations. We present the successful correction of bilateral Stahl's ear deformity in a newborn through a straightforward, nonsurgical method implemented on the first day of life. The aim of this report is to make pediatric practitioners aware of an effective and simple molding technique appropriate for correction of congenital auricular anomalies. In addition, it stresses the importance of very early initiation of ear cartilage molding for achieving the desired outcome.

  7. The Elastic Mold Deformation During the Filling and Packing Stage of the Injection Molding Process

    Directory of Open Access Journals (Sweden)

    Stefan Kleindel

    2014-03-01

    Full Text Available The accurate numerical prediction of the mold filling process of long and thin walled parts is dependent on numerous factors. This paper investigates the effect of various influencing variables on the filling pattern by means of simulation and experimental validation. It was found that mold temperature, process settings and venting conditions have little effect on the predicted filling pattern. However, in the actual case study, the filling behavior observed during the experiments was significantly different compared to the numerical prediction. A structural finite element analysis of the moving mold half showed an unacceptable large deformation of the mold plates under injection pressure. A very good correlation between simulation and experiment was attained after improving the stiffness of the mold. Therefore it can be concluded, that the elasticity of the mold may have a significant influence on the filling pattern when long and thin walled products are considered. Furthermore, it was shown, that even an apparently stiff mold can exhibit a distinct deformation during filling and packing stage.

  8. Two-dimensional differential adherence of neuroblasts in laser micromachined CAD/CAM agarose channels

    Energy Technology Data Exchange (ETDEWEB)

    Doraiswamy, A. [Georgia Institute of Technology, School of Material Science and Engineering, Atlanta, GA 30332 (United States); Patz, T. [Georgia Institute of Technology, School of Material Science and Engineering, Atlanta, GA 30332 (United States); Narayan, R.J. [Georgia Institute of Technology, School of Material Science and Engineering, Atlanta, GA 30332 (United States); Dinescu, M. [National Institute for Laser, Plasma and Radiation Physics, P.O. Box MG-16 Magurele, 077125 Bucharest (Romania); Modi, R. [US Naval Research Laboratory, Washington, DC 20375-5345 (United States); Auyeung, R.C.Y. [US Naval Research Laboratory, Washington, DC 20375-5345 (United States); Chrisey, D.B. [US Naval Research Laboratory, Washington, DC 20375-5345 (United States)

    2006-04-30

    Laser micromachining of hydrophobic gels into CAD/CAM patterns was used to develop differentially adherent surfaces and induce the attachment of B35 rat neuroblasts that would later form engineered nerve bundles. Narrow channels, 60-400 {mu}m wide, were micromachined in a 2% agarose gel using an ArF laser, and subsequently filled with an extracellular matrix gel. Upon the addition of 1 ml of a 2 x 104 cells/ml neuroblast suspension, the cells selectively adhered to the ECM-lined channels in a non-confluent manner and we monitored their growth at various time points. The adherent neuroblasts were fluorescently imaged with a propidium iodide live/dead assay, which revealed that the cells were alive within the channels. After 72 h growth, the neuroblasts grew, proliferated, and differentiated into nerve bundles. The fully grown 1 cm long nerve bundle organoids maintained an aspect ratio on the order of 100. The results presented in this paper provide the foundation for laser micromachining technique to develop bioactive substrates for development of three-dimensional tissues. Laser micromachining offers rapid prototyping of substrates, excellent resolution, control of pattern depth and dimensions, and ease of fabrication.

  9. Two-dimensional differential adherence of neuroblasts in laser micromachined CAD/CAM agarose channels

    International Nuclear Information System (INIS)

    Laser micromachining of hydrophobic gels into CAD/CAM patterns was used to develop differentially adherent surfaces and induce the attachment of B35 rat neuroblasts that would later form engineered nerve bundles. Narrow channels, 60-400 μm wide, were micromachined in a 2% agarose gel using an ArF laser, and subsequently filled with an extracellular matrix gel. Upon the addition of 1 ml of a 2 x 104 cells/ml neuroblast suspension, the cells selectively adhered to the ECM-lined channels in a non-confluent manner and we monitored their growth at various time points. The adherent neuroblasts were fluorescently imaged with a propidium iodide live/dead assay, which revealed that the cells were alive within the channels. After 72 h growth, the neuroblasts grew, proliferated, and differentiated into nerve bundles. The fully grown 1 cm long nerve bundle organoids maintained an aspect ratio on the order of 100. The results presented in this paper provide the foundation for laser micromachining technique to develop bioactive substrates for development of three-dimensional tissues. Laser micromachining offers rapid prototyping of substrates, excellent resolution, control of pattern depth and dimensions, and ease of fabrication

  10. Dense Pellicular Agarose-Glass Beads for Expanded Bed Application: Flow Hydrodynamics and Solid Phase Classifications

    Institute of Scientific and Technical Information of China (English)

    周鑫; 史清洪; 白姝; 孙彦

    2004-01-01

    Two dense pellicular agarose-glass matrices of different sizes and densities, i.e., AG-S and AG-L, have been characterized for their bed expansion behavior, flow hydrodynamics and particle classifications in an expanded bed system. A 26 mm ID column with side ports was used for sampling the liquid-solid suspension during expanded bed operations. Measurements of the collected solid phase at different column positions yielded the particle size and density distribution data. It was found that the composite matrices showed particle size as well as density classifications along the column axis, i.e., both the size and density of each matrix decreased with increasing the axial bed height. Their axial classifications were expressed by a correlation related to both the particle size and density as a function of the dimensionless axial bed height. The correlation was found to fairly describe the solid phase classifications in the expanded bed system. Moreover, it can also be applied to other two commercial solid matrices designed for expanded bed applications.

  11. Uranium (VI) recovery from aqueous medium using novel floating macroporous alginate-agarose-magnetite cryobeads

    Energy Technology Data Exchange (ETDEWEB)

    Tripathi, Anuj, E-mail: chianuj@gmail.com [Nuclear Agriculture and Biotechnology Division, Bhabha Atomic Research Center, Trombay, Mumbai 400085 (India); Melo, Jose Savio, E-mail: jsmelo@barc.gov.in [Nuclear Agriculture and Biotechnology Division, Bhabha Atomic Research Center, Trombay, Mumbai 400085 (India); D' Souza, Stanislaus Francis, E-mail: sfdsouza@barc.gov.in [Nuclear Agriculture and Biotechnology Division, Bhabha Atomic Research Center, Trombay, Mumbai 400085 (India)

    2013-02-15

    Highlights: ► Designing of floating biopolymeric-magnetite cryobeads using cryotropic-gelation. ► Optimization of preparation process and their physico-chemical characterization. ► First study on the floating cryobeads for uranium recovery application. ► Cost effective synthesis and environment-friendly for environmental applications. -- Abstract: This study presents a novel development of a floating polymeric-magnetite cryobead for the recovery of hexavalent uranium from the aqueous sub-surfaces. The alginate-agarose-magnetite cryobeads were synthesized by the process of cryotropic-gelation at subzero-temperature. The physico-chemical properties of cryobeads showed high surface area and high interconnected porosity (∼90%). Low density of these cryobeads explains their floating property in the aqueous medium. The rheological analysis of cryobeads showed its stability and increased stiffness after uranium adsorption. The presence of magnetite nanoparticles in the porous cryobeads facilitates the recovery of these beads by applying an external magnetic field. Maximum uranium adsorption (97 ± 2%) was observed in the pH range of 4.5–5.5. The thermodynamic parameters suggest passive endothermic adsorption behaviour. HCl was found to be an efficient eluent for the uranium desorption. Five repeated cycles for the desorption of uranium from biosorbent showed 69 ± 3% of uranium recovery. These results suggest stability of these novel floating magnetite-cryobeads under environmetal conditions with potential for the recovery of uranium from contaminated aqueous subsurfaces.

  12. Uranium (VI) recovery from aqueous medium using novel floating macroporous alginate-agarose-magnetite cryobeads.

    Science.gov (United States)

    Tripathi, Anuj; Melo, Jose Savio; D'Souza, Stanislaus Francis

    2013-02-15

    This study presents a novel development of a floating polymeric-magnetite cryobead for the recovery of hexavalent uranium from the aqueous sub-surfaces. The alginate-agarose-magnetite cryobeads were synthesized by the process of cryotropic-gelation at subzero-temperature. The physico-chemical properties of cryobeads showed high surface area and high interconnected porosity (≈ 90%). Low density of these cryobeads explains their floating property in the aqueous medium. The rheological analysis of cryobeads showed its stability and increased stiffness after uranium adsorption. The presence of magnetite nanoparticles in the porous cryobeads facilitates the recovery of these beads by applying an external magnetic field. Maximum uranium adsorption (97 ± 2%) was observed in the pH range of 4.5-5.5. The thermodynamic parameters suggest passive endothermic adsorption behaviour. HCl was found to be an efficient eluent for the uranium desorption. Five repeated cycles for the desorption of uranium from biosorbent showed 69 ± 3% of uranium recovery. These results suggest stability of these novel floating magnetite-cryobeads under environmental conditions with potential for the recovery of uranium from contaminated aqueous subsurfaces. PMID:23280054

  13. Upregulation of matrix synthesis in chondrocyte-seeded agarose following sustained bi-axial cyclic loading

    Directory of Open Access Journals (Sweden)

    Belinda Pingguan-Murphy

    2012-08-01

    Full Text Available OBJECTIVES: The promotion of extracellular matrix synthesis by chondrocytes is a requisite part of an effective cartilage tissue engineering strategy. The aim of this in vitro study was to determine the effect of bi-axial cyclic mechanical loading on cell proliferation and the synthesis of glycosaminoglycans by chondrocytes in threedimensional cultures. METHOD: A strain comprising 10% direct compression and 1% compressive shear was applied to bovine chondrocytes seeded in an agarose gel during two 12-hour conditioning periods separated by a 12-hour resting period. RESULTS: The bi-axial-loaded chondrocytes demonstrated a significant increase in glycosaminoglycan synthesis compared with samples exposed to uni-axial or no loading over the same period (p<0.05. The use of a free-swelling recovery period prior to the loading regime resulted in additional glycosaminoglycan production and a significant increase in DNA content (p<0.05, indicating cell proliferation. CONCLUSIONS: These results demonstrate that the use of a bi-axial loading regime results in increased matrix production compared with uni-axial loading.

  14. Stabilization of Candida antarctica Lipase B (CALB Immobilized on Octyl Agarose by Treatment with Polyethyleneimine (PEI

    Directory of Open Access Journals (Sweden)

    Sara Peirce

    2016-06-01

    Full Text Available Lipase B from Candida antarctica (CALB was immobilized on octyl agarose (OC and physically modified with polyethyleneimine (PEI in order to confer a strong ion exchange character to the enzyme and thus enable the immobilization of other enzymes on its surface. The enzyme activity was fully maintained during the coating and the thermal stability was marginally improved. The enzyme release from the support by incubation in the non-ionic detergent Triton X-100 was more difficult after the PEI-coating, suggesting that some intermolecular physical crosslinking had occurred, making this desorption more difficult. Thermal stability was marginally improved, but the stability of the OCCALB-PEI was significantly better than that of OCCALB during inactivation in mixtures of aqueous buffer and organic cosolvents. SDS-PAGE analysis of the inactivated biocatalyst showed the OCCALB released some enzyme to the medium during inactivation, and this was partially prevented by coating with PEI. This effect was obtained without preventing the possibility of reuse of the support by incubation in 2% ionic detergents. That way, this modified CALB not only has a strong anion exchange nature, while maintaining the activity, but it also shows improved stability under diverse reaction conditions without affecting the reversibility of the immobilization.

  15. Powder injection molding of pure titanium

    Institute of Scientific and Technical Information of China (English)

    GUO Shibo; DUAN Bohua; HE Xinbo; QU Xuanhui

    2009-01-01

    An improved wax-based binder was developed for powder injection molding of pure titanium. A critical powder loading of 69 vol.% and a pseudo-plastic flow behavior were obtained by the feedstock based on the binder. The injection molding, debinding, and sintering process were studied. An ideal control of carbon and oxygen contents was achieved by thermal debinding in vacuum atmosphere (10-3 Pa). The mechanical properties of as-sintered specimens were less than those of titanium made by the conventional press-sintering process. Good shape retention and ±0.04 mm dimension deviation were achieved.

  16. Modelling and monitoring in injection molding

    DEFF Research Database (Denmark)

    Thyregod, Peter

    2001-01-01

    . >From analysis of quality measurements from a longer period of manufacturing, it was found that differences in cavities was that source of variation with greatest influence on the lenght of the molded parts. The other large contribution to the lenght varation was the different machine settings. Samples...... a parts lenght and the producing cavitys position in the mold. In a designed expriment it was possible to isolate the machine parameters contributing to the variation beteeen cavities. Thus, with a proper choice of levels for the machine variables, it was possible to reduce the varation between cavities...

  17. Relationship Between Casting Distortion, Mold Filling, and Interfacial Heat Transfer in Sand Molds

    Energy Technology Data Exchange (ETDEWEB)

    J. K. Parker; K. A. Woodbury; T. S. Piwonka; Y. Owusu

    1999-09-30

    This project sought to determine the relationship between casting dimensions and interfacial heat transfer in aluminum alloy sand castings. The program had four parts; measurement of interfacial heat transfer coefficients in resin bonded and green sand molds, the measurement of gap formation in these molds, the analysis of castings made in varying gatings, orientations and thicknesses, and the measurement of residual stresses in castings in the as-cast and gate removed condition. New values for interfacial heat transfer coefficients were measured, a novel method for gap formation was developed, and the variation of casting dimensions with casting method, gating, and casting orientation in the mold was documented.

  18. Molding of Aluminum Foams by Using Hot Powder Extrusion

    Directory of Open Access Journals (Sweden)

    Yoshitaka Tanino

    2012-06-01

    Full Text Available In order to form aluminum foams directly from powder, a combined process of hot powder extrusion and molding is proposed. Aluminum powder mixed with a foaming agent is extruded into the mold through the die heated to a temperature higher than the melting point, and the mold is filled with the aluminum foam. When a stainless steel pipe is used for a simple mold, an aluminum foam bar is obtained of which the relative density varies between 0.2 and 0.3. The molding of aluminum foam by using three types of mold shape shows the influence of gravity and friction. The effect of gravity is significant when a large step exists at the connection between the mold inlet and the die outlet, and friction is dominant in cases where foam is mold in a narrow space.

  19. Tool steel quality and surface finishing of plastic molds

    Directory of Open Access Journals (Sweden)

    Rafael Agnelli Mesquita

    2010-01-01

    Full Text Available Plastic industry is today in a constant growth, demanding several products from other segments, which includes the plastic molds, mainly used in the injection molding process. Considering all the requirements of plastic molds, the surface finishing is of special interest, as the injected plastic part is able to reproduce any details (and also defects from the mold surface. Therefore, several aspects on mold finishing are important, mainly related to manufacturing conditions - machining, grinding, polishing and texturing, and also related to the tool steel quality, in relation to microstructure homogeneity and non-metallic inclusions (cleanliness. The present paper is then focused on this interrelationship between steel quality and manufacturing process, which are both related to the final quality of plastic mold surfaces. Examples are discussed in terms of surface finishing of plastic molds and the properties or the microstructure of mold steels.

  20. Chemotaxis in the Plasmodial Slime Mold, Physarum polycephalum.

    Science.gov (United States)

    Bozzone, Donna M.; Martin, Denise A.

    1998-01-01

    Describes a biology unit designed so that students pose their own questions and perform experiments to answer these questions. Plasmodial slime mold is employed as the focus of the study with background information about the mold provided. (DDR)

  1. COMPUTER AIDED THREE DIMENSIONAL DESIGN OF MOLD COMPONENTS

    Directory of Open Access Journals (Sweden)

    Kerim ÇETİNKAYA

    2000-02-01

    Full Text Available Sheet metal molding design with classical methods is formed in very long times calculates and drafts. At the molding design, selection and drafting of most of the components requires very long time because of similar repetative processes. In this study, a molding design program has been developed by using AutoLISP which has been adapted AutoCAD packet program. With this study, design of sheet metal molding, dimensioning, assemly drafting has been realized.

  2. Enhancing dry adhesives and replica molding with ethyl cyano-acrylate

    Science.gov (United States)

    Bovero, E.; Menon, C.

    2014-08-01

    The use of cyano-acrylate to improve the performance of dry adhesives and their method of fabrication is investigated. Specifically, the contributions of this work are: (1) a new adhesion method to adhere to a large variety of surfaces, (2) a strategy to increase the compliance of dry adhesives, and (3) an improved fabrication process for micro-structured dry adhesives based on replica molding. For the first contribution, the adhesion method consists of anchoring a micro-structured dry adhesive to a surface through a layer of hardened ethyl cyano-acrylate (ECA). This method increases the adhesion of the orders of magnitude at the expense of leaving residue after detachment. However, this method preserves reusability. For the second contribution, a double-sided dry adhesive is obtained by introducing a substrate with a millimeter-sized pillar structure, which enabled further increasing adhesion. For the third contribution, an ECA layer is used as a mold for the fabrication of new adhesives. These new types of molds proved able to produce dry adhesives with high reproducibility and low degradation.

  3. 340 Facility compliance assessment

    International Nuclear Information System (INIS)

    This study provides an environmental compliance evaluation of the RLWS and the RPS systems of the 340 Facility. The emphasis of the evaluation centers on compliance with WAC requirements for hazardous and mixed waste facilities, federal regulations, and Westinghouse Hanford Company (WHC) requirements pertinent to the operation of the 340 Facility. The 340 Facility is not covered under either an interim status Part A permit or a RCRA Part B permit. The detailed discussion of compliance deficiencies are summarized in Section 2.0. This includes items of significance that require action to ensure facility compliance with WAC, federal regulations, and WHC requirements. Outstanding issues exist for radioactive airborne effluent sampling and monitoring, radioactive liquid effluent sampling and monitoring, non-radioactive liquid effluent sampling and monitoring, less than 90 day waste storage tanks, and requirements for a permitted facility

  4. Compliance for Green IT

    CERN Document Server

    Calder, Alan

    2009-01-01

    The growing range of Green IT regulations are challenging more and more organisations to take specific steps to ensure they are in compliance with sometimes complex regulations, ranging from cap & trade requirements through to regulations concerning IT equipment disposal.

  5. Environmental Compliance Guide

    International Nuclear Information System (INIS)

    The Guide is intended to assist Department of Energy personnel by providing information on the NEPA process, the processes of other environmental statutes that bear on the NEPA process, the timing relationships between the NEPA process and these other processes, as well as timing relationships between the NEPA process and the development process for policies, programs, and projects. This information should be helpful not only in formulating environmental compliance plans but also in achieving compliance with NEPA and various other environmental statutes. The Guide is divided into three parts with related appendices: Part I provides guidance for developing environmental compliance plans for DOE actions; Part II is devoted to NEPA with detailed flowcharts depicting the compliance procedures required by CEQ regulations and Department of Energy NEPA Guidelines; and Part III contains a series of flowcharts for other Federal environmental requirements that may apply to DOE projects

  6. Environmental Compliance Guide

    Energy Technology Data Exchange (ETDEWEB)

    None

    1981-02-01

    The Guide is intended to assist Department of Energy personnel by providing information on the NEPA process, the processes of other environmental statutes that bear on the NEPA process, the timing relationships between the NEPA process and these other processes, as well as timing relationships between the NEPA process and the development process for policies, programs, and projects. This information should be helpful not only in formulating environmental compliance plans but also in achieving compliance with NEPA and various other environmental statutes. The Guide is divided into three parts with related appendices: Part I provides guidance for developing environmental compliance plans for DOE actions; Part II is devoted to NEPA with detailed flowcharts depicting the compliance procedures required by CEQ regulations and Department of Energy NEPA Guidelines; and Part III contains a series of flowcharts for other Federal environmental requirements that may apply to DOE projects.

  7. Single-Cell-Arrayed Agarose Chip for in Situ Analysis of Cytotoxicity and Genotoxicity of DNA Cross-Linking Agents.

    Science.gov (United States)

    Li, Lili; Wang, Weixing; Ding, Mingyu; Luo, Guoan; Liang, Qionglin

    2016-07-01

    Development of approach or device to allow continuous multiple measurements, such as integrating cytotoxic and genotoxic analysis, is quite appealing for study of the drug's activity and mechanism of action or resistance. In this study, a single-cell-arrayed agarose chip system was developed to combine cell cultivation with subsequent in situ analysis of cytotoxicity and genotoxicity of the chemotherapeutic agent. The modified alkaline comet assay coupled with the Live/Dead assay was used to monitor the interstrand cross-links (ICLs) formation and the cytotoxic effects in different glioma cell lines. In addition, the ICL-induced double strand breaks (DSBs) was measured on the chip to reflect the level of ICLs indirectly. Compared with the traditional methods, the microarray agarose device offers higher throughput, reproducibility, and robustness, exhibiting good potential for high-content drug screening. PMID:27269449

  8. Preparation of a novel pH optical sensor using orange (II) based on agarose membrane as support.

    Science.gov (United States)

    Heydari, Rouhollah; Hosseini, Mohammad; Amraei, Ahmadreza; Mohammadzadeh, Ali

    2016-04-01

    A novel and cost effective optical pH sensor was prepared using covalent immobilization of orange (II) indicator on the agarose membrane as solid support. The fabricated optical sensor was fixed into a sample holder of a spectrophotometer instrument for pH monitoring. Variables affecting sensor performance including pH of dye bonding to agarose membrane and dye concentration were optimized. The sensor responds to the pH changes in the range of 3.0-10.0 with a response time of 2.0 min and appropriate reproducibility (RSD ≤ 0.9%). No significant variation was observed on sensor response after increasing the ionic strength in the range of 0.0-0.5M of sodium chloride. Determination of pH using the proposed optical sensor is quick, simple, inexpensive, selective and sensitive in the pH range of 3.0-10.0.

  9. Separation of galactose, 5-hydroxymethylfurfural and levulinic acid in acid hydrolysate of agarose by nanofiltration and electrodialysis.

    Science.gov (United States)

    Kim, Jae Hyung; Na, Jeong-Geol; Yang, Ji-Won; Chang, Yong Keun

    2013-07-01

    A two-stage membrane process for the separation of galactose, 5-hydroxymethylfurfural (5-HMF) and levulinic acid (LA) has been proposed. The first step of nanofiltration (NF) is to remove 5-HMF and LA from galactose solution obtained by the hydrolysis of agarose, the main component of red algal galactan for the reduction of its microbial toxicity. 5-HMF and LA are inhibitory to fermentation but at the same time useful compounds themselves with many applications. The second step of electrodialysis (ED) is to separate 5-HMF and LA in the permeate from NF. More than 91% of 5-HMF and up to 62% of LA could be removed from agarose hydrolysate, while galactose was almost completely retained by NF. Further removal of LA was expected to be possible with no loss of galactose by operating the NF process in a diafiltration mode. 5-HMF and LA could be effectively separated from each other by ED. PMID:23672940

  10. Penetration Deep into Tissues of Reactive Oxygen Species Generated in Floating-Electrode Dielectric Barrier Discharge (FE-DBD): in Vitro Agarose Gel Model Mimicking an Open Wound

    CERN Document Server

    Dobrynin, Danil; Friedman, Gary; Fridman, Alexander

    2013-01-01

    In this manuscript we present an in vitro model based on agarose gel that can be used to simulate a dirty, oily, bloody, and morphologically complex surface of, for example, an open wound. We show this models effectiveness in simulating depth of penetration of reactive species generated in plasma deep into tissue of a rat and confirm the penetration depths with agarose gel model. We envision that in the future such a model could be used to study plasma discharges (and other modalities) and minimize the use of live animals: plasma can be optimized on the agarose gel wound model and then finally verified using an actual wound.

  11. Compliance with physical exercise

    DEFF Research Database (Denmark)

    Gram, Anne Sofie; Bønnelycke, Julie; Rosenkilde Larsen, Mads;

    2014-01-01

    ), a post hoc thematic analysis was conducted to connect qualitative and quantitative data in a joint analysis. Results: Of the subjects interviewed, exercise compliance expressed as 95% CI was [96.8; 103%] in the MOD group and [82.9; 99.6%] in the HIGH group. The different doses of daily exercise equally...... or quantitative methodology alone. The preconditions of the TBP were fulfilled, and it represents a methodological model to explain the high degree of compliance and motivation to exercise....

  12. Implementing a compliance manager

    OpenAIRE

    Armitage, S; Stevens, R.; Finkelstein, A.

    1998-01-01

    Many companies claim to adhere to standards for software project development. This is often used as a marketing tool when eliciting business. But how does the customer or project manager know that these standards are being completely and consistently applied in their projects? In the paper 'Managing Standards Compliance', we identify this problem and describe a support environment to provide identification and correction of non-compliance to standards. This paper details the experiences gaine...

  13. Comparison of two setups for induction heating in injection molding

    DEFF Research Database (Denmark)

    Menotti, Stefano; Hansen, Hans Nørgaard; Bissacco, Giuliano;

    2015-01-01

    To eliminate defects and improve the quality of molded parts, increasing the mold temperature is one of the applicable solutions. A high mold temperature can increase the path flow of the polymer inside the cavity allowing reduction of the number of injection points, reduction of part thickness, ...

  14. 21 CFR 874.3430 - Middle ear mold.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Middle ear mold. 874.3430 Section 874.3430 Food... DEVICES EAR, NOSE, AND THROAT DEVICES Prosthetic Devices § 874.3430 Middle ear mold. (a) Identification. A middle ear mold is a preformed device that is intended to be implanted to reconstruct the middle...

  15. Replication of optical microlens arrays using photoresist coated molds

    DEFF Research Database (Denmark)

    Chakrabarti, Maumita; Dam-Hansen, Carsten; Stubager, Jørgen;

    2016-01-01

    A cost reduced method of producing injection molding tools is reported and demonstrated for the fabrication of optical microlens arrays. A standard computer-numerical-control (CNC) milling machine was used to make a rough mold in steel. Surface treatment of the steel mold by spray coating...

  16. In vitro study of using calcium phosphate cement as immunoisolative device to enclose insulinoma/agarose microspheres as bioartificial pancreas.

    Science.gov (United States)

    Kai-Chiang, Yang; Ching-Yao, Yang; Chang-Chin, Wu; Tzong-Fu, Kuo; Feng-Huei, Lin

    2007-12-15

    In this study, the feasibility of using calcium phosphate cement (CPC) as immunoisolative device to enclose insulinoma/agarose microspheres as bioartificial pancreas was evaluated. We fabricated a chamber by CPC and utilized X-ray diffraction, Scanning electron microscope and Mercury intrusion porosimetry to identify the characters of the CPC chamber. The nominal molecular weight cut-off and cytotoxicity of CPC chamber were also evaluated. An insulinoma cell line (RIN-m5F) was chosen as insulin source and encapsulated in agarose microspheres and then enclosed in preformed CPC chamber. Insulin secretion was analyzed by Enzyme-linked immunosorbant assay to evaluate the function of insulinoma enclosed in CPC chamber. Results showed that the CPC chamber was non-cytotoxicity to insulinoma and can block the penetration of molecules which molecular weight larger than 12.4 kDa. Insulinoma inside the CPC chamber can secrete insulin in stable level for 30 days. This study indicated that we may use CPC as immunoisolative material to enclose insulinoma/agarose microspheres as bioartificial pancreas. PMID:17514757

  17. Molding cork sheets to complex shapes

    Science.gov (United States)

    Sharpe, M. H.; Simpson, W. G.; Walker, H. M.

    1977-01-01

    Partially cured cork sheet is easily formed to complex shapes and then final-cured. Temperature and pressure levels required for process depend upon resin system used and final density and strength desired. Sheet can be bonded to surface during final cure, or can be first-formed in mold and bonded to surface in separate step.

  18. Residual stresses in injection molded products

    NARCIS (Netherlands)

    Jansen, K.M.B.

    2015-01-01

    During the molding process residual stresses are formed due to thermal contraction during cooling as well as the local pressure history during solidification. In this paper a simple analytical model is reviewed which relates residual stresses, product shrinkage as well as warpage to the temperature

  19. Injection molding of micro patterned PMMA plate

    Institute of Scientific and Technical Information of China (English)

    Yeong-Eun YOO; Tae-Hoon KIM; Tae-Jin JE; Doo-Sun CHOI; Chang-Wan KIM; Sun-Kyung KIM

    2011-01-01

    A plastic plate with surface micro features was injection molded to investigate the effect of pressure rise of melt on the replication of the micro structures. Prism pattern, which is used in many optical applications, was selected as a model pattern. The prism pattern is 50 μm in pitch and 108° in the vertical angle. The overall size of the plate was 335 mm×213 mm and the thickness of the plate varied linearly from 2.6 mm to 0.7 mm. The prism pattern was firstly machined on the nickel plated core block using micro diamond tool and this machined pattern core was installed in a mold for injection molding of prism patterned plate. Polymethyl methacrylate (PMMA) was used as a molding material. The pressure and temperature of the melt in the cavity were measured at different positions in the cavity and the replication of the pattern was also measured at the same positions. The results show that the pressure or temperature profile through the process depends on the shape and the size of the plate. The replication is affected by the temperature and pressure profiles at the early stage of filling, which is right after the melt reaches the position to be measured.

  20. Fabrication of silicon molds for polymer optics

    DEFF Research Database (Denmark)

    Nilsson, Daniel; Jensen, Søren; Menon, Aric Kumaran

    2003-01-01

    A silicon mold used for structuring polymer microcavities for optical applications is fabricated, using a combination of DRIE (deep reactive ion etching) and anisotropic chemical wet etching with KOH + IPA. For polymer optical microcavities, low surface roughness and vertical sidewalls are often...

  1. Solvent-assisted polymer micro-molding

    Institute of Scientific and Technical Information of China (English)

    HAN LuLu; ZHOU Jing; GONG Xiao; GAO ChangYou

    2009-01-01

    The micro-molding technology has played an important role in fabrication of polymer micro-patterns and development of functional devices.In such a process,suitable solvent can swell or dissolve the polymer films to decrease their glass transition temperature (Tg) and viscosity and thereby improve flowing ability.Consequently,it is easy to obtain the 2D and 3D patterns with high fidelity by the solvent-assisted micro-molding.Compared with the high temperature molding,this technology overcomes some shortcomings such as shrinking after cooling,degradation at high temperature,difficulty in processing some functional materials having high Tg,etc.It can be applied to making patterns not only on polymer monolayers but also on polyelectrolyte multilayers.Moreover,the compressioninduced patterns on the multilayers are chemically homogenous but physically heterogeneous.In this review,the controlling factors on the pattern quality are also discussed,including materials of the mold,solvent,pressure,temperature and pattern density.

  2. [Cutaneous mold fungus granuloma from Ulocladium chartarum].

    Science.gov (United States)

    Altmeyer, P; Schon, K

    1981-01-01

    Cutaneous granulomas due to the mold fungus Ulocladium chartarum (Preuss) are described in a 58 year old woman. This fungus is usually harmless for mammalian. It is thought that a consisting immunosuppression (Brill-Symmer's disease, therapy with corticosteroids) was a priming condition for the infection. The route of infection in this patient described is unknown. PMID:7194869

  3. Streaming instability of aggregating slime mold amoebae

    Science.gov (United States)

    Levine, Herbert; Reynolds, William

    1991-05-01

    We propose a new model of aggregation in the cellular slime mold D. Discoideum. Our approach couples the excitable signaling system to amoeba chemotaxis; the resultant system of equations is tractable to analytical and numerical approaches. Using our model, we derive the existence of a streaming instability for the concentric target aggregation pattern.

  4. Polyamide 6 - long glass fiber injection moldings

    NARCIS (Netherlands)

    Bijsterbosch, H.; Gaymans, R.J.

    1995-01-01

    The injection molding ability of long glass fiber reinforced polyamide pellets was studied. The injection moldable materials were produced by a melt impregnation process of continuous fiber rovings. The rovings were chopped to pellets of 9 mm length. Chopped pellets with a variation in the degree of

  5. Onychomycosis by molds. Report of 78 cases.

    Science.gov (United States)

    Bonifaz, Alexandro; Cruz-Aguilar, Pamela; Ponce, Rosa María

    2007-01-01

    A retrospective study of onychomycohosis by molds was carried out during a 14-year period (1992-2005). All cases were clinically and mycologically proven (repetitive KOH and culture) and then each of the molds was identified. A total of 5,221 cases of onychomycosis were evaluated, 78 of which were molds (1.49%). Mean patient age was 44.1 years. 75/78 cases occurred in toenails. Associated factors were detected in 39/78 (50.0%) cases, with the major ones being: peripheral vascular disease, contact with soil, and trauma. The most frequent clinical presentation was distal and lateral subungual onychomycosis (DLSO), in 54/78 cases (69%). The most frequent causative agents were: Scopulariopsis brevicaulis in 34/78 cases and Aspergillus niger in 13/78 cases. Onychomycoses by molds are infrequent; in this study they accounted for 1.49% of cases. The clinical features are virtually similar to those caused by dermatophytes, which makes the clinicomycological tests necessary.

  6. Progress in Titanium Metal Powder Injection Molding

    Directory of Open Access Journals (Sweden)

    Randall M. German

    2013-08-01

    Full Text Available Metal powder injection molding is a shaping technology that has achieved solid scientific underpinnings. It is from this science base that recent progress has occurred in titanium powder injection molding. Much of the progress awaited development of the required particles with specific characteristics of particle size, particle shape, and purity. The production of titanium components by injection molding is stabilized by a good understanding of how each process variable impacts density and impurity level. As summarized here, recent research has isolated the four critical success factors in titanium metal powder injection molding (Ti-MIM that must be simultaneously satisfied—density, purity, alloying, and microstructure. The critical role of density and impurities, and the inability to remove impurities with sintering, compels attention to starting Ti-MIM with high quality alloy powders. This article addresses the four critical success factors to rationalize Ti-MIM processing conditions to the requirements for demanding applications in aerospace and medical fields. Based on extensive research, a baseline process is identified and reported here with attention to linking mechanical properties to the four critical success factors.

  7. Effect of mold treatment by solvent on PDMS molding into nanoholes

    OpenAIRE

    Con, Celal; Cui, Bo

    2013-01-01

    Polydimethylsiloxane (PDMS) is the most popular and versatile material for soft lithography due to its flexibility and easy fabrication by molding process. However, for nanoscale patterns, it is challenging to fill uncured PDMS into the holes or trenches on the master mold that is coated with a silane anti-adhesion layer needed for clean demolding. PDMS filling was previously found to be facilitated by diluting it with toluene or hexane, which was attributed to the great reduction of viscosit...

  8. Characteristics and influence factors of mold filling process in permanent mold with a slot gating system

    Institute of Scientific and Technical Information of China (English)

    Chang Qingming; Chen Xia; Chen Changjun; Bao Siqian; David Schwam

    2009-01-01

    The main problems caused by improper gating are entrained aluminum oxide films and entrapped gas. In this study, the slot gating system is employed to improve mold filling behavior and therefore, to improve the quality of aluminum castings produced in permanent molds. An equipment as well as operation procedures for real-time X-ray radiography of molten aluminum flowing into permanent molds have been developed. Graphite molds transparent to X-rays are utilized which make it possible to observe the flow pattern through a number of vertically oriented gating systems. The investigation discovers that there are many influencing factors on the mold filling process. This paper focuses its research on some of the factors, such as the dimensions of the vertical riser and slot thickness, as well as roughness of the coating layer. The results indicate that molten metal can smoothly fill into casting cavity with a proper slot gating system. A bigger vertical riser, proper slot thickness and rougher coating can provide not only a better mold filling pattern, but also hot melt into the top of the cavity. A proper temperature gradient is obtainable, higher at the bottom and lower at the top of the casting cavity, which is in favor of feeding during casting solidification.

  9. Fast prototyping of injection molded polymer microfluidic chips

    DEFF Research Database (Denmark)

    Hansen, Thomas Steen; Selmeczi, David; Larsen, Niels Bent

    2010-01-01

    We present fast prototyping of injection molding tools by the definition of microfluidic structures in a light-curable epoxy (SU-8) directly on planar nickel mold inserts. Optimized prototype mold structures could withstand injection molding of more than 300 replicas in cyclic olefin copolymer (COC......, likely due to the resulting reduction in sidewall steepness. We employed the latter method for injection molding bondable polymer microfluidic chips with integrated conducting polymer electrode arrays that permitted the culture and on-chip analysis of cell spreading by impedance spectroscopy....

  10. The Facility and Process Technics of Polyethylene Rotational Molding

    Institute of Scientific and Technical Information of China (English)

    LI BaiShun

    2001-01-01

    @@ 1. Introduction Rotational molding is the process by which hollow plastic parts are formed. It mainly processes the product which Injection molding and Blow molding can not process medium-sized, large-sized and super large-sized plastic parts. The technics may turn out a tub, dustbin, stock tank, sailboat. The research institute of Lanzhou introduces a suit of RS-16 Rotational Molding Machine from Germany Reinhadt Co. on 1990. It mainly put up experiment and smallscale production. RS-16 rotational molding machine is a single arm and di-axial equipment. It is consisting of a gas heated sintering oven, cooling chamber, mouldcarrying carriage and a controlling unit.

  11. Computer simulation for centrifugal mold filling of precision titanium castings

    Institute of Scientific and Technical Information of China (English)

    2004-01-01

    Computer simulation codes were developed based on a proposed mathematical model for centrifugal mold filling processes and previous computer software for 3D mold filling and solidification of castings (CASM-3D for Windows). Sample simulations were implemented for mold filling processes of precision titanium castings under gravity and different centrifugal casting techniques. The computation results show that the alloy melt has a much stronger mold filling ability for thin section castings under a centrifugal force field than that only under the gravity. A "return back" mold filling manner is showed to be a reasonable technique for centrifugal casting processes, especially for thin section precision castings.

  12. Stability of FDTS monolayer coating on aluminum injection molding tools

    DEFF Research Database (Denmark)

    Cech, Jiri; Taboryski, Rafael J.

    2012-01-01

    The injection molding industry often employs prototype molds and mold inserts from melt spun (rapid solidification processing [1,2]) aluminum, especially for applications in optics [3,4], photonics [5] and microfludics. Prototypes are also used for verification of mold filling. The use of aluminum...... tools has reduced lead time (days instead of weeks) and manufacturing cost (30% of conventional mold). Moreover, for aluminum, a surface roughness (RMS) below 5 nm can be obtained with diamond machining [3,4,6]. Conventional mold coatings add cost and complexity, and coatings with thicknesses of a few...... trichloro-silane based coating deposited on aluminum or its alloys by molecular vapor deposition. We have tested the stability of this coating in challenging conditions of injection molding, an environment with high shear stress from the molten polymer, pressures up to 200 MPa, temperatures up to 250 ◦C...

  13. Mold exposure and health effects following hurricanes Katrina and Rita.

    Science.gov (United States)

    Barbeau, Deborah N; Grimsley, L Faye; White, LuAnn E; El-Dahr, Jane M; Lichtveld, Maureen

    2010-01-01

    The extensive flooding in the aftermath of Hurricanes Katrina and Rita created conditions ideal for indoor mold growth, raising concerns about the possible adverse health effects associated with indoor mold exposure. Studies evaluating the levels of indoor and outdoor molds in the months following the hurricanes found high levels of mold growth. Homes with greater flood damage, especially those with >3 feet of indoor flooding, demonstrated higher levels of mold growth compared with homes with little or no flooding. Water intrusion due to roof damage was also associated with mold growth. However, no increase in the occurrence of adverse health outcomes has been observed in published reports to date. This article considers reasons why studies of mold exposure after the hurricane do not show a greater health impact. PMID:20070193

  14. A comparison of molding procedures - Contact, injection and vacuum injection

    Science.gov (United States)

    Cathiard, G.

    1980-06-01

    The technical and economic aspects of the contact, injection and vacuum injection molding of reinforced plastic components are compared for the example of a tractor roof with a gel-coated surface. Consideration is given to the possibility of reinforcement, number of smooth faces, condition of the gel-coated surface, reliability, and labor and workplace requirements of the three processes, and advantages of molding between the mold and a countermold in smooth faces, reliability, labor requirements, working surface and industrial hygiene are pointed out. The times and labor requirements of each step in the molding cycles are examined, and material requirements and yields, investment costs, amortization and product cost prices of the processes are compared. It is concluded that, for the specific component examined, the processes of vacuum injection and injection molding appear very interesting, with injection molding processes resulting in lower cost prices than contact molding for any production volume.

  15. ICIS FE&C Compliance Monitoring Screens

    Data.gov (United States)

    U.S. Environmental Protection Agency — Web Based Training for Integrated Compliance Information System Updated Compliance Monitoring Training for ICIS Federal Enforcement and Compliance User. This...

  16. Compliance and phototherapy.

    Science.gov (United States)

    Brownell, Joshua; Wang, Stephanie; Tsoukas, Maria M

    2016-01-01

    When beginning a phototherapy regimen for a patient, consideration of compliance rates is important. Compliance to phototherapy can be affected by several factors, including the grade of discomfort and side effects from therapy, failure of previous therapies, accessibility and convenience to reach the phototherapy center, grade of improvement during phototherapy, patient relief due to light therapy, and rapport with staff. Understanding how these factors can affect patient adherence can allow for phototherapy regimens to be tailored in a manner that optimizes health outcomes and allows for proper patient selection. PMID:27638436

  17. An education belief worth reflection: Molding intellectuals

    Institute of Scientific and Technical Information of China (English)

    Lu Jie

    2006-01-01

    Molding intellectuals is one of the expectations people have,which comes from a deep-rooted belief in education.The humanity hypothesis of this belief is to take knowledge and the pursuit of knowledge as the only prescription for human beings.This hypothesis overturns the relation of knowledge and life.Intellectuals make scientific paradigm as the limit of knowledge.Experience and consciousness outside the paradigm are ejected from the scope of knowledge.Accordingly,knowledge of intellectuals is broken away from a human being's life.Under the domination of this conception of knowledge,the world of intellectuals has become a world deficient of meaning.The belief that education molds intellectuals should be deconstructed gradually,with criticism in both practice and theory.

  18. Future Specialist’s Professional Position Molding

    OpenAIRE

    Irina A. Levitskaya

    2013-01-01

    The search of conditions for future specialist’s professional position molding is crucial nowadays. This article discloses the features of “position” notion essence in the context of professional self-determination, analyses the problems of future specialist’s professional development in terms of topical social and professional objectives solution, considers debatable issues of professional development as an integral continuous process of future specialist’s personality formation. The stages ...

  19. Gastroresistant capsular device prepared by injection molding.

    Science.gov (United States)

    Zema, Lucia; Loreti, Giulia; Melocchi, Alice; Maroni, Alessandra; Palugan, Luca; Gazzaniga, Andrea

    2013-01-20

    In the present work, the possibility of manufacturing by injection molding (IM) a gastro-resistant capsular device based on hydroxypropyl methyl cellulose acetate succinate (HPMCAS) was investigated. By performing as an enteric soluble container, such a device may provide a basis for the development of advantageous alternatives to coated dosage forms. Preliminarily, the processability of the selected thermoplastic polymer was evaluated, and the need for a plasticizer (polyethylene glycol 1500) in order to counterbalance the glassy nature of the molded items was assessed. However, some critical issues related to the physical/mechanical stability (shrinkage and warpage) and opening time of the device after the pH change were highlighted. Accordingly, an in-depth formulation study was carried out taking into account differing release modifiers potentially useful for enhancing the dissolution/disintegration rate of the capsular device at intestinal pH values. Capsule prototypes with thickness of 600 and 900 μm containing Kollicoat(®) IR and/or Explotab(®) CLV could be manufactured, and a promising performance was achieved with appropriate gastric resistance in pH 1.2 medium and break-up in pH 6.8 within 1h. These results would support the design of a dedicated mold for the development of a scalable manufacturing process. PMID:22683648

  20. Fractal phenomena in powder injection molding process

    Institute of Scientific and Technical Information of China (English)

    郑洲顺; 曲选辉; 李云平; 雷长明; 段柏华

    2003-01-01

    The complicated characteristics of the powder were studied by fractal theory. It is illustrated that powder shape, binder structure, feedstock and mold-filling flow in powder injection molding process possess obvious fractal characteristics. Based on the result of SEM, the fractal dimensions of the projected boundary of carbonylic iron and carbonylic nickel particles were determined to be 1.074±0.006 and 1.230±0.005 respectively by box counting measurement. The results show that the fractal dimension of the projected boundary of carbonylic iron particles is close to smooth curve of one-dimension, while the fractal dimension of the projected boundary of carbonylic nickel particle is close to that of trisection Koch curve, indicating that the shape characteristics of carbonylic nickel particles can be described and analyzed by the characteristics of trisection Koch curve. It is also proposed that the fractal theory can be applied in the research of powder injection molding in four aspects.

  1. Environmental compliance and cleanup

    Energy Technology Data Exchange (ETDEWEB)

    Black, D.G.

    1995-06-01

    This section of the 1994 Hanford Site Environmental Report summarizes the roles of the principal agencies, organizations, and public in environmental compliance and cleanup of the Hanford Site. Regulatory oversight, the Federal Facility Agreement and Consent Order, the role of Indian tribes, public participation, and CERCLA Natural Resource Damage Assessment Trustee Activities are all discussed.

  2. Interpersonal Communication and Compliance

    NARCIS (Netherlands)

    Fennis, Bob M.; Das, Enny; Pruyn, Ad Th.H.

    2006-01-01

    Two field experiments examined the impact of the Disrupt-Then-Reframe (DTR) technique on compliance. This recently identified technique consists of a subtle, odd element in a typical scripted request (the disruption) followed by a persuasive phrase (the reframing). The authors argued that its impact

  3. Making corporate compliance programs work.

    Science.gov (United States)

    Chibbaro, M J; Colyer, C

    2000-05-01

    Healthcare organizations have created corporate compliance programs in an effort to adhere to Federal government recommendations, minimize the risk of wrongful behavior, and possibly reduce fines that may result from a government investigation. Compliance programs may have undetected weaknesses. Corporate compliance officers, executives, and board members need to be certain that their organization's program has sufficient infrastructure, oversight, and resources; effective education and training; an effective mechanism (hotline) to receive reports of compliance problems; and ongoing auditing and monitoring capabilities.

  4. Microinjection molding of thermoplastic polymers: morphological comparison with conventional injection molding

    Science.gov (United States)

    Giboz, Julien; Copponnex, Thierry; Mélé, Patrice

    2009-02-01

    The skin-core crystalline morphology of injection-molded semi-crystalline polymers is well documented in the scientific literature. The thermomechanical environment provokes temperature and shear gradients throughout the entire thickness of the part during molding, thus influencing the polymer crystallization. Crystalline morphologies of a high-density polyethylene (HDPE) micromolded part (μpart) and a classical part (macropart) are compared with optical, thermal and x-ray diffraction analyses. Results show that the crystalline morphologies with regard to thickness vary between the two parts. While a 'skin-core' morphology is present for the macropart, the μpart exhibits a specific 'core-free' morphology, i.e. no spherulite is present at the center of the thickness. This result seems to be generated under the specific conditions used in microinjection molding that lead to the formation of smaller and more oriented crystalline entities.

  5. Effect of mold treatment by solvent on PDMS molding into nanoholes

    Science.gov (United States)

    Con, Celal; Cui, Bo

    2013-09-01

    Polydimethylsiloxane (PDMS) is the most popular and versatile material for soft lithography due to its flexibility and easy fabrication by molding process. However, for nanoscale patterns, it is challenging to fill uncured PDMS into the holes or trenches on the master mold that is coated with a silane anti-adhesion layer needed for clean demolding. PDMS filling was previously found to be facilitated by diluting it with toluene or hexane, which was attributed to the great reduction of viscosity for diluted PDMS. Here, we suggest that the reason behind the improved filling for diluted PDMS is that the diluent solvent increases in situ the surface energy of the silane-treated mold and thus the wetting of PDMS to the mold surface. We treated the master mold surface (that was already coated with a silane anti-adhesion monolayer) with toluene or hexane, and found that the filling by undiluted PMDS into the nanoscale holes on the master mold was improved despite the high viscosity of the undiluted PDMS. A simple estimation based on capillary filing into a channel also gives a filling time on the millisecond scale, which implies that the viscosity of PMDS should not be the limiting factor. We achieved a hole filling down to sub-200-nm diameter that is smaller than those of the previous studies using regular Sylgard PDMS (not hard PDMS, Dow Corning Corporation, Midland, MI, USA). However, we are not able to explain using a simple argument based on wetting property why smaller, e.g., sub-100-nm holes, cannot be filled, for which we suggested a few possible factors for its explanation.

  6. Snow molds: A group of fungi that prevail under snow.

    Science.gov (United States)

    Matsumoto, Naoyuki

    2009-01-01

    Snow molds are a group of fungi that attack dormant plants under snow. In this paper, their survival strategies are illustrated with regard to adaptation to the unique environment under snow. Snow molds consist of diverse taxonomic groups and are divided into obligate and facultative fungi. Obligate snow molds exclusively prevail during winter with or without snow, whereas facultative snow molds can thrive even in the growing season of plants. Snow molds grow at low temperatures in habitats where antagonists are practically absent, and host plants deteriorate due to inhibited photosynthesis under snow. These features characterize snow molds as opportunistic parasites. The environment under snow represents a habitat where resources available are limited. There are two contrasting strategies for resource utilization, i.e., individualisms and collectivism. Freeze tolerance is also critical for them to survive freezing temperatures, and several mechanisms are illustrated. Finally, strategies to cope with annual fluctuations in snow cover are discussed in terms of predictability of the habitat.

  7. Mold deformation in soft UV-nanoimprint lithography

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    UV-nanoimprint lithography (UV-NIL) using a soft mold is a promising technique with low cost and high throughput for producing the submicron scale large-area patterns. However, the deformations of the soft mold during imprinting process which can cause serious consequences have to be understood for the practical application of the process. This paper investigated the deformation of the soft mold by theoretical analyses, numerical simulations, and experimental studies. We simulated the mold deformation using a simplified model and finite element method. The simulation and the related experimental results agree well with each other. Through the investigation, the mechanism and affected factors of the mold deformation are revealed, and some useful conclusions have been achieved. These results will be valuable in optimizing the imprinting process conditions and mold design for improving the quality of transferred patterns.

  8. Shape retention of injection molded stainless steel compacts

    Institute of Scientific and Technical Information of China (English)

    LI Yi-min; K.A.Khalil; HUANG Bai-yun

    2005-01-01

    The effects of the binder composition, the powder loading, the thermal properties of feedstocks, and the injection molding parameters on the compact shape retention for metal injection molding 17-4PH stainless steel were investigated. The high-density polyethylene is more effective than ethylene vinyl acetate as a second component of the wax-based binder to retain compact shape due to its higher pyrolytic temperature and less heat of fusion. The compact distortion decreases with increasing the powder loading, molding pressure and molding temperature. There exists an optimal process combination including the powder loading of 68%, molding pressure of 120 MPa and molding temperature of 150 ℃. Under this process condition, the percentage of distorted compacts is the lowest.

  9. Mold deformation in soft UV-nanoimprint lithography

    Institute of Scientific and Technical Information of China (English)

    LAN HongBo; DING YuCheng; LIU HongZhong; QUE YeRong; TAO WeiWei; LI HanSong; LU BingHeng

    2009-01-01

    UV-nanoimprint lithography (UV-NIL) using a soft mold is a promising technique with low cost and high throughput for producing the submicron scale large-area patterns. However, the deformations of the soft mold during imprinting process which can cause serious consequences have to be understood for the practical application of the process. This paper investigated the deformation of the soil mold by theoretical analyses, numerical simulations, and experimental studies. We simulated the mold defor-mation using a simplified model and finite element method. The simulation and the related experimental results agree well with each other. Through the investigation, the mechanism and affected factors of the mold deformation are revealed, and some useful conclusions have been achieved. These results will be valuable in optimizing the imprinting process conditions and mold design for improving the quality of transferred patterns.

  10. Process and part filling control in micro injection molding

    DEFF Research Database (Denmark)

    Tosello, Guido; Hansen, Hans Nørgaard; Schoth, Andreas

    2008-01-01

    The influence of process parameters on μ-injection molding (μIM) and on μ-injection molded parts has been investigated using Design of Experiments. A mold with a sensor applied at injection location was used to monitor actual injection pressure and to determine the cavity filling time. Flow markers...... injection speed in one of the most influencing process parameters on the μIM process and on the μ-parts filling....

  11. Virtual Mold Technique in Thermal Stress Analysis during Casting Process

    Institute of Scientific and Technical Information of China (English)

    Si-Young Kwak; Jae-Wook Baek; Jeong-Ho Nam; Jeong-Kil Choi

    2008-01-01

    It is important to analyse the casting product and the mold at the same time considering thermal contraction of the casting and thermal expansion of the mold. The analysis considering contact of the casting and the mold induces the precise prediction of stress distribution and the defect such as hot tearing. But it is difficult to generate FEM mesh for the interface of the casting and the mold. Moreover the mesh for the mold domain spends lots of computational time and memory for the analysis due to a number of meshes. Consequently we proposed the virtual mold technique which only uses mesh of the casting part for thermal stress analysis in casting process. The spring bar element in virtual mold technique is used to consider the contact of the casting and the mold. In general, a volume of the mold is much bigger than that of casting part, so the proposed technique decreases the number of mesh and saves the computational memory and time greatly. In this study, the proposed technique was verified by the comparison with the traditional contact technique on a specimen. And the proposed technique gave satisfactory results.

  12. Mold and human health: separating the wheat from the chaff.

    Science.gov (United States)

    Pettigrew, H David; Selmi, Carlo F; Teuber, Suzanne S; Gershwin, M Eric

    2010-04-01

    The term "mold" is utilized to define the ubiquitous fungal species commonly found in household dust and observed as visible multicellular filaments. Several well-defined human diseases are known to be caused or exacerbated by mold or by exposure to their byproducts. Among these, a solid connection has been established with infections, allergic bronchopulmonary aspergillosis, allergic fungal rhinosinusitis, hypersensitivity pneumonitis, and asthma. In the past decades, other less-defined and generally false conditions have also been ascribed to mold. We will herein review and critically discuss the available evidence on the influence of mold on human health. PMID:19714500

  13. Effect of mold rotation on the bifilar electroslag remelting process

    Institute of Scientific and Technical Information of China (English)

    Xiao-fang Shi; Li-zhong Chang; Jian-jun Wang

    2015-01-01

    A novel electroslag furnace with a rotating mold was fabricated, and the effects of mold rotational speed on the electroslag re-melting process were investigated. The results showed that the chemical element distribution in ingots became uniform and that their com-pact density increased when the mold rotational speed was increased from 0 to 28 r/min. These results were attributed to a reasonable mold speed, which resulted in a uniform temperature in the slag pool and scattered the metal droplets randomly in the metal pool. However, an ex-cessive rotational speed caused deterioration of the solidification structure. When the mold rotational speeds was increased from 0 to 28 r/min, the size of Al2O3 inclusions in the electroslag ingot decreased from 4.4 to 1.9μm. But the excessive mold rotational speed would de-crease the ability of the electroslag remelting to remove the inclusions. The remelting speed gradually increased, which resulted in reduced power consumption with increasing mold rotational speed. This effect was attributed to accelerated heat exchange between the consumable electrode and the molten slag, which resulted from mold rotation. Nevertheless, when the rotational speed reached 28 r/min, the remelting speed did not change because of limitations of metal heat conduction. Mold rotation also improved the surface quality of the ingots by pro-moting a uniform temperature distribution in the slag pool.

  14. Determining iron oxide nanoparticle heating efficiency and elucidating local nanoparticle temperature for application in agarose gel-based tumor model.

    Science.gov (United States)

    Shah, Rhythm R; Dombrowsky, Alexander R; Paulson, Abigail L; Johnson, Margaret P; Nikles, David E; Brazel, Christopher S

    2016-11-01

    Magnetic iron oxide nanoparticles (MNPs) have been developed for magnetic fluid hyperthermia (MFH) cancer therapy, where cancer cells are treated through the heat generated by application of a high frequency magnetic field. This heat has also been proposed as a mechanism to trigger release of chemotherapy agents. In each of these cases, MNPs with optimal heating performance can be used to maximize therapeutic effect while minimizing the required dosage of MNPs. In this study, the heating efficiencies (or specific absorption rate, SAR) of two types of MNPs were evaluated experimentally and then predicted from their magnetic properties. MNPs were also incorporated in the core of poly(ethylene glycol-b-caprolactone) micelles, co-localized with rhodamine B fluorescent dye attached to polycaprolactone to monitor local, nanoscale temperatures during magnetic heating. Despite a relatively high SAR produced by these MNPs, no significant temperature rise beyond that observed in the bulk solution was measured by fluorescence in the core of the magnetic micelles. MNPs were also incorporated into a macro-scale agarose gel system that mimicked a tumor targeted by MNPs and surrounded by healthy tissues. The agarose-based tumor models showed that targeted MNPs can reach hyperthermia temperatures inside a tumor with a sufficient MNP concentration, while causing minimal temperature rise in the healthy tissue surrounding the tumor. PMID:27523991

  15. Supplementation of exogenous adenosine 5'-triphosphate enhances mechanical properties of 3D cell-agarose constructs for cartilage tissue engineering.

    Science.gov (United States)

    Gadjanski, Ivana; Yodmuang, Supansa; Spiller, Kara; Bhumiratana, Sarindr; Vunjak-Novakovic, Gordana

    2013-10-01

    Formation of tissue-engineered cartilage is greatly enhanced by mechanical stimulation. However, direct mechanical stimulation is not always a suitable method, and the utilization of mechanisms underlying mechanotransduction might allow for a highly effective and less aggressive alternate means of stimulation. In particular, the purinergic, adenosine 5'-triphosphate (ATP)-mediated signaling pathway is strongly implicated in mechanotransduction within the articular cartilage. We investigated the effects of transient and continuous exogenous ATP supplementation on mechanical properties of cartilaginous constructs engineered using bovine chondrocytes and human mesenchymal stem cells (hMSCs) encapsulated in an agarose hydrogel. For both cell types, we have observed significant increases in equilibrium and dynamic compressive moduli after transient ATP treatment applied in the fourth week of cultivation. Continuous ATP treatment over 4 weeks of culture only slightly improved the mechanical properties of the constructs, without major changes in the total glycosaminoglycan (GAG) and collagen content. Structure-function analyses showed that transiently ATP-treated constructs, and in particular those based on hMSCs, had the highest level of correlation between compositional and mechanical properties. Transiently treated groups showed intense staining of the territorial matrix for GAGs and collagen type II. These results indicate that transient ATP treatment can improve functional mechanical properties of cartilaginous constructs based on chondrogenic cells and agarose hydrogels, possibly by improving the structural organization of the bulk phase and territorial extracellular matrix (ECM), that is, by increasing correlation slopes between the content of the ECM components (GAG, collagen) and mechanical properties of the construct.

  16. Probing the transport of plasma-generated RONS in an agarose target as surrogate for real tissue: dependency on time, distance and material composition

    International Nuclear Information System (INIS)

    We report a simple experimental approach to follow the transport of helium (He) plasma-generated reactive oxygen and nitrogen species (RONS) through millimetre thick agarose targets. These RONS may be either primary RONS, generated directly by the plasma jet, or secondary RONS generated for example at the surface of, or within, the material. Our experiment involves placing an agarose film over a quartz cuvette filled with deionized water. The agarose film is exposed to a He plasma jet and the UV absorption profile (of the deionized water) is recorded in real-time. Plasma exposure time, source-target distance and agarose film thickness and composition are varied to explore their effects on the depth of RONS delivery by the plasma jet. We conclude that plasma UV plays a minor role in the transport of RONS; whereas direct plasma contact and the He gas flow promote the transport of RONS into tissue. Our data indicate an accumulation of RONS within the agarose film (during plasma exposure) and a subsequent (time-lagged) release into the deionized water. Our approach can be readily adapted to other plasma sources; it can accommodate more complex biological materials, and has the potential to provide new insights into plasma-induced phenomena within real tissues. (fast track communication)

  17. Evolution of Surface Texture and Cracks During Injection Molding of Fiber-Reinforced, Additively-Manufactured, Injection Molding Inserts

    DEFF Research Database (Denmark)

    Hofstätter, Thomas; Mischkot, Michael; Pedersen, David Bue;

    2016-01-01

    This paper investigates the lifetime and surfacedeterioration of additively-manufactured, injection-moulding inserts. The inserts were produced using digital light processing and were reinforcedwith oriented short carbon fibers. Theinserts were used during injection molding oflow......-density polyethylene until their failure. The molded products were used to analyse the development of the surface roughness and wear. By enhancing the lifetime of injection-molding inserts,this work contributes to the establishment of additively manufactured inserts in pilot production....

  18. Mold Filling Analysis in Vacuum Infusion Molding Process Based on a High-Permeable Medium

    Institute of Scientific and Technical Information of China (English)

    Yingdan ZHU; Hua TAN; Jihui WANG

    2003-01-01

    The objective of this paper is to understand the flow mechanism through visualization experiments and discuss theinfluence of process parameters on mold filling process. A 2D leakage flow model is developed to simulate the moldingprocess, and the simulation results show good agreement with experiments.

  19. Comparison of injection molding and injection/compression molding for the replication of microstructure

    Science.gov (United States)

    Hong, Seokkwan; Hwang, Jeongho; Kang, Jeongjin; Yoon, Kyunghwan

    2015-11-01

    Because of increasing interest in the functional surfaces including micro- or nano-patterns, the mass production of such surfaces has been actively researched. Both conventional injection molding (CIM) and injection/compression molding (ICM) of micro-patterns were investigated in the present study. The molding subject is a multi-scale structure that consists of a macro-scale thin plate and micro-scale patterns formed regularly on its surface. The transcription ratios of micro pattern made by CIM and ICM for different flow length were experimentally measured, and the origin of the obtained results was identified through numerical analysis. It was found that the cavity pressure and polymer temperature are the most important factors for micro-pattern filling; in particular, the polymer temperature is the key factor determining the transcription ratio. It was also found that the difference in CIM and ICM micro-pattern transcription ratios originates from the differences in the cavity pressure history if other molding conditions are the same.

  20. Investigations on injection molded, glass-fiber reinforced polyamide 6 integral foams using breathing mold technology

    Science.gov (United States)

    Roch, A.; Kehret, L.; Huber, T.; Henning, F.; Elsner, P.

    2015-05-01

    Investigations on PA6-GF50 integral foams have been carried out using different material systems: longfiber- and shortfiber-reinforced PA6 as well as unreinforced PA6 as a reference material. Both chemical and physical blowing agents were applied. Breathing mold technology (decompression of the mold) was selected for the foaming process. The integral foam design, which can be conceived as a sandwich structure, helps to save material in the neutral axis area and maintains a distance between load-bearing, unfoamed skin layers. For all test series an initial mold gap of 2.5 mm was chosen and the same amount of material was injected. In order to realize different density reductions, the mold opening stroke was varied. The experiments showed that, at a constant mass per unit area, integral polyamide 6 foams have a significantly higher bending stiffness than compact components, due to their higher area moment of inertia after foaming. At a constant surface weight the bending stiffness in these experiments could be increased by up to 600 %. Both shortfiber- and longfiber-reinforced polyamide 6 showed an increase in energy absorption during foaming.

  1. Importance of Molds for Nanoimprint Lithography: Hard, Soft, and Hybrid Molds

    Directory of Open Access Journals (Sweden)

    B. Kwon

    2016-01-01

    Full Text Available Nanoimprint lithography has attracted considerable attention in academic and industrial fields as one of the most prominent lithographic techniques for the fabrication of the nanoscale devices. Effectively controllable shapes of fabricated elements, extremely high resolution, and cost-effectiveness of this especial lithographic system have shown unlimited potential to be utilized for practical applications. In the past decade, many different lithographic techniques have been developed such as electron beam lithography, photolithography, and nanoimprint lithography. Among them, nanoimprint lithography has proven to have not only various advantages that other lithographic techniques have but also potential to minimize the limitations of current lithographic techniques. In this review, we summarize current lithography techniques and, furthermore, investigate the nanoimprint lithography in detail in particular focusing on the types of molds. Nanoimprint lithography can be categorized into three different techniques (hard-mold, soft-mold, and hybrid nanoimprint depending upon the molds for imprint with different advantages and disadvantages. With numerous studies and improvements, nanoimprint lithography has shown great potential which maximizes its effectiveness in patterning by minimizing its limitations. This technique will surely be the next generation lithographic technique which will open the new paradigm for the patterning and fabrication in nanoscale devices in industry.

  2. Pathology-designed custom molded foot orthoses.

    Science.gov (United States)

    Rosenbloom, Kevin B

    2011-01-01

    Treating patients with custom foot orthoses for common pathologies is a rewarding experience when the proper steps are taken during foot casting and custom-orthosis prescription writing. This article describes successful methods for orthoses casting and prescription writing for custom-molded orthoses for Achilles tendonitis, pes planus, hallux limitus, plantar fasciitis/heel spurs, lateral ankle instability, metatarsalgia, and pes cavus. In addition, a summary of orthotic laboratory instructions for each pathology-designed custom orthosis is provided, which should be considered by orthotic laboratories. PMID:21276525

  3. Integrally cored ceramic investment casting mold fabricated by ceramic stereolithography

    Science.gov (United States)

    Bae, Chang-Jun

    Superalloy airfoils are produced by investment casting (IC), which uses ceramic cores and wax patterns with ceramic shell molds. Hollow cored superalloy airfoils in a gas turbine engine are an example of complex IC parts. The complex internal hollow cavities of the airfoil are designed to conduct cooling air through one or more passageways. These complex internal passageways have been fabricated by a lost wax process requiring several processing steps; core preparation, injection molding for wax pattern, and dipping process for ceramic shell molds. Several steps generate problems such as high cost and decreased accuracy of the ceramic mold. For example, costly tooling and production delay are required to produce mold dies for complex cores and wax patterns used in injection molding, resulting in a big obstacle for prototypes and smaller production runs. Rather than using separate cores, patterns, and shell molds, it would be advantageous to directly produce a mold that has the casting cavity and the ceramic core by one process. Ceramic stereolithography (CerSLA) can be used to directly fabricate the integrally cored ceramic casting mold (ICCM). CerSLA builds ceramic green objects from CAD files from many thin liquid layers of powder in monomer, which are solidified by polymerization with a UV laser, thereby "writing" the design for each slice. This dissertation addresses the integrally cored casting ceramic mold (ICCM), the ceramic core with a ceramic mold shell in a single patternless construction, fabricated by ceramic stereolithography (CerSLA). CerSLA is considered as an alternative method to replace lost wax processes, for small production runs or designs too complex for conventional cores and patterns. The main topic is the development of methods to successfully fabricate an ICCM by CerSLA from refractory silica, as well as related issues. The related issues are the segregation of coarse fused silica powders in a layer, the degree of segregation parameter to

  4. True arterial system compliance estimated from apparent arterial compliance.

    Science.gov (United States)

    Quick, C M; Berger, D S; Hettrick, D A; Noordergraaf, A

    2000-03-01

    A new method has been developed to estimate total arterial compliance from measured input pressure and flow. In contrast to other methods, this method does not rely on fitting the elements of a lumped model to measured data. Instead, it relies on measured input impedance and peripheral resistance to calculate the relationship of arterial blood volume to input pressure. Generally, this transfer function is a complex function of frequency and is called the apparent arterial compliance. At very low frequencies, the confounding effect of pulse wave reflection disappears, and apparent compliance becomes total arterial compliance. This study reveals that frequency components of pressure and flow below heart rate are generally necessary to obtain a valid estimate of compliance. Thus, the ubiquitous practice of estimating total arterial compliance from a single cardiac cycle is suspect under most circumstances, since a single cardiac cycle does not contain these frequencies. PMID:10784093

  5. Sinterability of Zirconia Top Coat of Investment Mold for Ti Alloy

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    In this paper, zirconia is used as top mold material for Ti investment casting. Top mold samples are made by proper mold building technology. The effect of different sintering temperature on chemical composition, microstructure and residual bending strength of the top mold sample is studied. The volume and homogeneity of the air holes in the top mold are determined by sintering temperature, and finally determined the residual bending strength of the mold sample was determined.

  6. Development of the computer-aided process planning (CAPP) system for polymer injection molds manufacturing

    OpenAIRE

    J. Tepić; V. Todić; Lukić, D.; Milošević, M.; Borojević, S.

    2011-01-01

    Beginning of production and selling of polymer products largely depends on mold manufacturing. The costs of mold manufacturing have significant share in the final price of a product. The best way to improve and rationalize polymer injection molds production process is by doing mold design automation and manufacturing process planning automation. This paper reviews development of a dedicated process planning system for manufacturing of the mold for injection molding, which integrates computer-...

  7. Composite fabrication via resin transfer molding technology

    Energy Technology Data Exchange (ETDEWEB)

    Jamison, G.M.; Domeier, L.A.

    1996-04-01

    The IMPReS (Integrated Modeling and Processing of Resin-based Structures) Program was funded in FY95 to consolidate, evaluate and enhance Sandia`s capabilities in the design and fabrication of composite structures. A key driver of this and related programs was the need for more agile product development processes and for model based design and fabrication tools across all of Sandia`s material technologies. A team of polymer, composite and modeling personnel was assembled to benchmark Sandia`s existing expertise in this area relative to industrial and academic programs and to initiate the tasks required to meet Sandia`s future needs. RTM (Resin Transfer Molding) was selected as the focus composite fabrication technology due to its versatility and growing use in industry. Modeling efforts focused on the prediction of composite mechanical properties and failure/damage mechanisms and also on the uncured resin flow processes typical of RTM. Appropriate molds and test composites were fabricated and model validation studies begun. This report summarizes and archives the modeling and fabrication studies carried out under IMPReS and evaluates the status of composite technology within Sandia. It should provide a complete and convenient baseline for future composite technology efforts within Sandia.

  8. Production of Liquid Metal Spheres by Molding

    Directory of Open Access Journals (Sweden)

    Mohammed G. Mohammed

    2014-10-01

    Full Text Available This paper demonstrates a molding technique for producing spheres composed of eutectic gallium-indium (EGaIn with diameters ranging from hundreds of microns to a couple millimeters. The technique starts by spreading EGaIn across an elastomeric sheet featuring cylindrical reservoirs defined by replica molding. The metal flows into these features during spreading. The spontaneous formation of a thin oxide layer on the liquid metal keeps the metal flush inside these reservoirs. Subsequent exposure to acid removes the oxide and causes the metal to bead up into a sphere with a size dictated by the volume of the reservoirs. This technique allows for the production and patterning of droplets with a wide range of volumes, from tens of nanoliters up to a few microliters. EGaIn spheres can be embedded or encased subsequently in polymer matrices using this technique. These spheres may be useful as solder bumps, electrodes, thermal contacts or components in microfluidic devices (valves, switches, pumps. The ease of parallel-processing and the ability to control the location of the droplets during their formation distinguishes this technique.

  9. Effect of antioxidants of aflatoxigenic molds

    International Nuclear Information System (INIS)

    Growth and aflatoxin production by Aspergillus flavus and A. parasiticus were measured in synthetic media and chicken feed treated with butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), ethoxyquin (EXQ), propyl gallate (PG) or t-butylhydroquinone (TBHQ) at 50-250 μg/g and 50-1000 μg/g, respectively. BHA at 50 μg/g in broth or agar inhibited growth and alfatoxin production by both molds. In poultry feeds, 1000 μg/g BHA was required to depress CO2 production at day 5 of incubation, while 200 μg/g decreased aflatoxin B1 23.8%. BHT, EXQ, and PG had slight effects on mold growth while TBHQ enhanced growth on broth but reduced it on agar. Afaltoxin B1 production was stimulated by EXQ, although G1 production declines. Measurement of cellular constituents released from mycelia over 5 hours indicated that BHA doubled the release of UV-absorbing materials and increase by threefold the release of previously incorporated radiolabeled compounds. Furthermore, BHA inhibited the uptake of 14C-amino acids 8 and 44%, 3H-uridine 65 and 91%, and 3H-methyl thymidine 67 and 71%, for A. flavus and A. parasiticus, respectively, compared to untreated controls

  10. Lighting molded optics: Design and manufacturing

    Directory of Open Access Journals (Sweden)

    Kočárková H.

    2013-05-01

    Full Text Available Proper design and manufacturing of glass molded lenses need to be performed in several steps. The whole process from customer requirements to f nal functional product is shown on two examples - a lens for street light and a lens for spot light with narrow lighting angle. After discussing customer requirements, optical design is made. Thanks to various commercial softwares with optimization, manufacturer of the lens can work as well as a designer which enables simplif cation and acceleration of lens manufacturing, since limitations of the manufacturing process are considered during creation of the design. When the prototype is made, its functionality needs to be evaluated. This work shows measurement of light distribution for street light lens in a dark room using goniometer and measurement of light intensity for spot lens f xed on an optical bench. These measurements can reveal the root cause in case of lens malfunction, which enables to optimize manufacturing process or modify lens design accordingly. Designing, manufacturing and evaluation of molded optics under one roof enables creation of easily manufacturable design and fast solution of problems.

  11. Gravitational response of the slime mold Physarum

    Science.gov (United States)

    Block, I.; Wolke, A.; Briegleb, W.

    1994-08-01

    The acellular slime mold Physarum polycephalum is used as a model system to investigate the graviresponse of single cells which possess no receptors specialized for the perception of gravity. To obtain insights into the gravity-signal transduciton mechanism the light response of the cell is used: Macroplsmodia of the slime mold show clear geo- and phototaxes. Gravity increases and white light decreases transiently the concentration frequency of plasmodial strands whereby both responses follow the same time pattern. Since mitochodria play major role in changing the contraction rhythm in response to light and gravity stimuli, the simultaneous and subsequent inductions of the opposing light and gravity responses and their mutual influences on one another were investigated. The experiments were performed in weightlessness (0 g) - simulated on the fast-rotating clinostat as well as in actual weightlessness during the IML-1 Space-Shuttle mission. The results indicate that mitochondria (chondriome) are part of the acceleration-stimulus reaction chain in Physarum. Two models for a direct gravireceptor mechanism are discussed.

  12. Effect of antioxidants of aflatoxigenic molds

    Energy Technology Data Exchange (ETDEWEB)

    Ahmad, M.M.

    1986-01-01

    Growth and aflatoxin production by Aspergillus flavus and A. parasiticus were measured in synthetic media and chicken feed treated with butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), ethoxyquin (EXQ), propyl gallate (PG) or t-butylhydroquinone (TBHQ) at 50-250 ..mu..g/g and 50-1000 ..mu..g/g, respectively. BHA at 50 ..mu..g/g in broth or agar inhibited growth and alfatoxin production by both molds. In poultry feeds, 1000 ..mu..g/g BHA was required to depress CO/sub 2/ production at day 5 of incubation, while 200 ..mu..g/g decreased aflatoxin B/sub 1/ 23.8%. BHT, EXQ, and PG had slight effects on mold growth while TBHQ enhanced growth on broth but reduced it on agar. Afaltoxin B/sub 1/ production was stimulated by EXQ, although G/sub 1/ production declines. Measurement of cellular constituents released from mycelia over 5 hours indicated that BHA doubled the release of UV-absorbing materials and increase by threefold the release of previously incorporated radiolabeled compounds. Furthermore, BHA inhibited the uptake of /sup 14/C-amino acids 8 and 44%, /sup 3/H-uridine 65 and 91%, and /sup 3/H-methyl thymidine 67 and 71%, for A. flavus and A. parasiticus, respectively, compared to untreated controls.

  13. Multi-height structures in injection molded polymer

    DEFF Research Database (Denmark)

    Andersen, Nis Korsgaard; Taboryski, Rafael J.

    2015-01-01

    We present the fabrication process for injection molded multi-height surface structures for studies of wetting behavior. We adapt the design of super hydrophobic structures to the fabrication constrictions imposed by industrial injection molding. This is important since many super hydrophobic...

  14. Characterization of white mold disease avoidance in common bean

    Science.gov (United States)

    White mold, caused by Sclerotinia sclerotiorum, is a devastating fungal disease of common bean (Phaseolus vulgaris L.) worldwide. Physiological resistance and disease avoidance conferred by plant architecture-related traits contribute to white mold field resistance. Our objective was to further exam...

  15. Grinding aspheric and freeform micro-optical molds

    Science.gov (United States)

    Tohme, Yazid E.

    2007-02-01

    Fueled by the need for better performing optics, glass optics are now replacing plastic optics in many industrial and consumer electronic devices. One of these devices is the mobile phone camera. The optical sub-assembly in a mobile phone includes several micro lenses that are spherical and/or aspherical in shape and require form tolerances in the submicron range. These micro glass lenses are mass produced by a replication process known as glass press molding. The process entails the compression of a glass gob between two precise optical quality molds at an elevated temperature, usually near the transition temperature of the glass material. The elevated forces and temperatures required in the glass molding process limits the materials of the molds to very tough materials such as tungsten carbide or silicon carbide. These materials can withstand large pressing forces at high temperatures without any significant deformation. These materials offer great mechanical properties for glass press molding but they are also a challenge to machine to submicron accuracy. The work in this paper discusses a deterministic micro grinding manufacturing process referred to as wheel normal grinding, which is utilized to produce these optical quality molds. Wheel normal grinding is more accurate and more deterministic than most other grinding techniques and can produce molds to the form and finish tolerances required for optical molding. This method relies on the ability to recognize and compensate for grinding wheel wear and machine repeatable errors. Results will be presented to illustrate the accuracy of this micro grinding technique.

  16. Taxonomic re-evaluation of black koji molds

    NARCIS (Netherlands)

    Hong, S.B.; Yamada, O.; Samson, R.A.

    2013-01-01

    Black koji molds including its albino mutant, the white koji mold, have been widely used for making the distilled spirit shochu in Northeast Asia because they produce citric acid which prevents undesirable contamination from bacteria. Since Inui reported Aspergillus luchuensis from black koji in Oki

  17. Injection molding of high aspect ratio sub-100 nm nanostructures

    DEFF Research Database (Denmark)

    Matschuk, Maria; Larsen, Niels B

    2013-01-01

    with FDTS. Reduced adhesion forces are consistent with lowered friction that reduces the risk of fracturing the nanoscopic pillars during demolding. Optimized mold surface chemistry and associated injection molding conditions permitted the fabrication of square arrays of 40 nm wide and 107 nm high (aspect...... ratio >2.5) pillars on a 200 nm pitch....

  18. Using Cellular Slime Molds in the High School Laboratory

    Science.gov (United States)

    Haskins, P. B.

    1977-01-01

    Described is the life cycle of the cellular slime molds Acrasiales. Experiments that can be used to explore the aggregation, migration, and culmination activities of the organism are suggested. Laboratory procedures for culturing these slime molds and listings of biological supply houses and literature references are also given. (MA)

  19. Two Species of Myxomycetes Causing Slime Mold of Sweet Potato

    OpenAIRE

    Kim, Wan Gyu; Lee, Sang Yeob; Cho, Weon Dae

    2007-01-01

    Specimens collected from sweet potato plants with slime mold symptoms in fields in Daejeon, Korea were examined. Two species of Myxomycetes, Fuligo septica and Stemonitis herbatica were identified based on their morphological characteristics. This is the first report that the two species of Myxomycetes cause slime mold of sweet potato in Korea.

  20. Occurrence of Fuligo gyrosa Causing Slime Mold of Oriental Melon

    OpenAIRE

    Kim, Wan Gyu; Choi, Hyo Won; Hong, Sung Kee; Lee, Young Kee; Lee, Su Heon

    2009-01-01

    Recently, a severe slime mold infestation affected oriental melon plants in fields in Chilgok county, Gyeongbuk province, Korea. Specimens were collected from the fields and examined for identification. A species of Myxomycetes, Fuligo gyrosa, was identified based on its morphological characteristics. This is the first report that F. gyrosa causes slime mold of oriental melon.

  1. Physarum attraction: Why slime mold behaves as cats do?

    OpenAIRE

    Adamatzky, Andrew; Costello, Ben de Lacy

    2012-01-01

    We discuss potential chemical substances responsible for attracting acellular slime mold Physarun polycephalum to valerian root. The contributes toward fundamental research into pheromones and chemo-attracts of primitive organisms such as slime molds. The results show that significant information could be gained about the action of compounds on higher organisms.

  2. A fabrication method of microneedle molds with controlled microstructures.

    Science.gov (United States)

    Wang, Qi Lei; Zhu, Dan Dan; Chen, Yang; Guo, Xin Dong

    2016-08-01

    Microneedle (MN) offers an attractive, painless and minimally invasive approach for transdermal drug delivery. Polymer microneedles are normally fabricated by using the micromolding method employing a MN mold, which is suitable for mass production due to high production efficiency and repeat-using of the mold. Most of the MN molds are prepared by pouring sylgard polymer over a MN master to make an inverse one after curing, which is limited in optimizing or controlling the MN structures and failing to keep the sharpness of MNs. In this work we describe a fabrication method of MN mold with controlled microstructures, which is meaningful for the fabrication of polymer MNs with different geometries. Laser micro-machining method was employed to drill on the surface of PDMS sheets to obtain MN molds. In the fabrication process, the microstructures of MN molds are precisely controlled by changing laser parameters and imported patterns. The MNs prepared from these molds are sharp enough to penetrate the skin. This scalable MN mold fabrication method is helpful for future applications of MNs.

  3. Three-Dimensional Modeling of Glass Lens Molding

    DEFF Research Database (Denmark)

    Sarhadi, Ali; Hattel, Jesper Henri; Hansen, Hans Nørgaard

    2015-01-01

    glass lens molding process. First, a comprehensive 3D thermo-mechanical model of glass is implemented into a FORTRAN user subroutine (UMAT) in the FE program ABAQUS, and the developed FE model is validated with both a well-known sandwich seal test and experimental results of precision molding of several...

  4. Compliance and noncompliance in asthma.

    Science.gov (United States)

    Kaiser, Harold B

    2007-01-01

    Compliance and noncompliance are big issues in asthma management. It has been well established that compliant patients experience less exacerbations than less compliant patients and that compliance rates often are <50%. The reasons for noncompliance are multiple and complex and not always clearly understood. Methods proposed to improve compliance include patient education, more partnership care, less frequent dosing, simple schedules, diaries, etc. Less dosing and simple schedules are most effective. It is difficult to improve compliance overall and despite extensive research and efforts, rates of compliance remain low. Noncompliance in asthma management is a fact of life and no single compliance-improving strategy probably will be as effective as a good physician-patient relationship. PMID:18034967

  5. Injection molding of bushes made of tribological PEEK composites

    Directory of Open Access Journals (Sweden)

    2007-12-01

    Full Text Available Polyetheretherketone (PEEK composites have been extensively studied because of the excellent tribological behavior among plastics. However, laboratory specimens and tests are generally discussed, whereas application studies on industrial components are infrequent. In this paper, an injection molded bush made of tribological PEEK was analyzed to correlate wear behavior and molded material structure. Bushes were tested under unlubricated sliding conditions by means of a short wear test. Surface analysis, differential scanning calorimetry (DSC and optical microscopy were used to evaluate the distribution of the different composite fillers (polytetrafluoroethylene, PTFE, graphite particles and carbon microfibers and their effect on the final bush behavior. A significant lack of homogeneity was observed in the molded bush and black bands appeared on the shaft surface after testing due to the sliding. The bush geometry and the injection molding process should be optimized to allow the best tribological behavior of the molded material under working conditions.

  6. Validation of three-dimensional micro injection molding simulation accuracy

    DEFF Research Database (Denmark)

    Tosello, Guido; Costa, F.S.; Hansen, Hans Nørgaard

    2011-01-01

    simulation accuracy (i.e. decrease deviations from experimental values): injection speed profile, cavity injection pressure, melt and mold temperatures, three-dimensional mesh parameters, and material rheological characterization. Quality factors investigated for the quantitative comparisons were: short shot...... length, injection pressure profile, molding mass and flow pattern. The importance of calibrated micro molding process monitoring for an accurate implementation strategy of the simulation and its validation has been demonstrated. In fact, inconsistencies and uncertainties in the experimental data must be......Data analysis and simulations on micro-molding experiments have been conducted. Micro molding simulations have been executed taking into account actual processing conditions implementation in the software. Various aspects of the simulation set-up have been considered in order to improve the...

  7. Standard Molded Composite Rocket Pyrogen Igniter - A progress report

    Science.gov (United States)

    Lucy, M. H.

    1978-01-01

    The pyrogen igniter has the function to furnish a controlled, high temperature, high pressure gas to ignite solid propellant surfaces in a rocket motor. Present pyrogens consist of numerous inert components. The Standard Molded Pyrogen Igniter (SMPI) consists of three basic parts, a cap with several integrally molded features, an ignition pellet retainer plate, and a tube with additional integrally molded features. A description is presented of an investigation which indicates that the SMPI concept is a viable approach to the design and manufacture of pyrogen igniters for solid propellant rocket motors. For some applications, combining the structural and thermal properties of molded composites can result in the manufacture of lighter assemblies at considerable cost reduction. It is demonstrated that high strength, thin walled tubes with high length to diameter ratios can be fabricated from reinforced plastic molding compound using the displacement compression process.

  8. OrmoStamp mold fabrication via PBW for NIL

    Energy Technology Data Exchange (ETDEWEB)

    Liu, F.; Yao, Y.; Kan, J.A. van, E-mail: phyjavk@nus.edu.sg

    2015-04-01

    Nanoimprint lithography (NIL) is a promising technology that can fabricate structures with high resolution and high throughput. To replicate patterns through NIL, a high quality master mold is needed. A UV patternable inorganic–organic hybrid polymer, OrmoStamp with high resolution is promising for the fabrication of NIL molds. Here, OrmoStamp molds were fabricated by proton beam writing (PBW) in resist followed by OrmoStamp casting. In this paper, different resists (HSQ, PMMA, SU-8 and SML) were evaluated by PBW for OrmoStamp mold fabrication. The results show that HSQ gives the smallest line width down to 30 nm. These lines have subsequently been successfully replicated in OrmoStamp. High aspect ratio structures in OrmoStamp and Ni were obtained from proton beam written resist samples, featuring an aspect ratio of ∼7 and ∼70, respectively. Finally thermal NIL has been demonstrated in PMMA using OrmoStamp molds.

  9. The Facility and Process Technics of Polyethylene Rotational Molding

    Institute of Scientific and Technical Information of China (English)

    LI; BaiShun

    2001-01-01

    1. Introduction Rotational molding is the process by which hollow plastic parts are formed. It mainly processes the product which Injection molding and Blow molding can not process medium-sized, large-sized and super large-sized plastic parts. The technics may turn out a tub, dustbin, stock tank, sailboat.  The research institute of Lanzhou introduces a suit of RS-16 Rotational Molding Machine from Germany Reinhadt Co. on 1990. It mainly put up experiment and smallscale production. RS-16 rotational molding machine is a single arm and di-axial equipment. It is consisting of a gas heated sintering oven, cooling chamber, mouldcarrying carriage and a controlling unit.  ……

  10. Mathematical modeling of the in-mold coating process for injection-molded thermoplastic parts

    Science.gov (United States)

    Chen, Xu

    In-Mold Coating (IMC) has been successfully used for many years for exterior body panels made from compression molded Sheet Molding Compound (SMC). The coating material is a single component reactive fluid, designed to improve the surface quality of SMC moldings in terms of functional and cosmetic properties. When injected onto a cured SMC part, IMC cures and bonds to provide a pain-like surface. Because of its distinct advantages, IMC is being considered for application to injection molded thermoplastic parts. For a successful in mold coating operation, there are two key issues related to the flow of the coating. First, the injection nozzle should be located such that the thermoplastic substrate is totally covered and the potential for air trapping is minimized. The selected location should be cosmetically acceptable since it most likely will leave a mark on the coated surface. The nozzle location also needs to be accessible for easy of maintenance. Secondly, the hydraulic force generated by the coating injection pressure should not exceed the available clamping tonnage. If the clamping force is exceeded, coating leakage will occur. In this study, mathematical models for IMC flow on the compressible thermoplastic substrate have been developed. Finite Difference Method (FDM) is first used to solve the 1 dimensional (1D) IMC flow problem. In order to investigate the application of Control Volume based Finite Element Method (CV/FEM) to more complicated two dimensional IMC flow, that method is first evaluated by solving the 1D IMC flow problem. An analytical solution, which can be obtained when a linear relationship between the coating thickness and coating injection pressure is assumed, is used to verify the numerical results. The mathematical models for the 2 dimensional (2D) IMC flow are based on the generalized Hele-Shaw approximation. It has been found experimentally that the power law viscosity model adequately predicts the rheological behavior of the coating

  11. Compliance with endogenous audit probabilities

    OpenAIRE

    Konrad, Kai A.; Lohse, Tim; Qari, Salmai

    2015-01-01

    This paper studies the effect of endogenous audit probabilities on reporting behavior in a face-to-face compliance situation such as at customs. In an experimental setting in which underreporting has a higher expected payoff than truthful reporting we find an increase in compliance of about 80% if subjects have reason to believe that their behavior towards an officer influences their endogenous audit probability. Higher compliance is driven by considerations about how own appearance and perfo...

  12. Public health and economic impact of dampness and mold

    Energy Technology Data Exchange (ETDEWEB)

    Mudarri, David; Fisk, William J.

    2007-06-01

    The public health risk and economic impact of dampness and mold exposures was assessed using current asthma as a health endpoint. Individual risk of current asthma from exposure to dampness and mold in homes from Fisk et al. (2007), and asthma risks calculated from additional studies that reported the prevalence of dampness and mold in homes were used to estimate the proportion of U.S. current asthma cases that are attributable to dampness and mold exposure at 21% (95% confidence internal 12-29%). An examination of the literature covering dampness and mold in schools, offices, and institutional buildings, which is summarized in the appendix, suggests that risks from exposure in these buildings are similar to risks from exposures in homes. Of the 21.8 million people reported to have asthma in the U.S., approximately 4.6 (2.7-6.3) million cases are estimated to be attributable to dampness and mold exposure in the home. Estimates of the national cost of asthma from two prior studies were updated to 2004 and used to estimate the economic impact of dampness and mold exposures. By applying the attributable fraction to the updated national annual cost of asthma, the national annual cost of asthma that is attributable to dampness and mold exposure in the home is estimated to be $3.5 billion ($2.1-4.8 billion). Analysis indicates that exposure to dampness and mold in buildings poses significant public health and economic risks in the U.S. These findings are compatible with public policies and programs that help control moisture and mold in buildings.

  13. CENTRAL CONVEYING & AUTO FEEDING SYSTEMS FOR AN INJECTION MOLDING SHOP

    Directory of Open Access Journals (Sweden)

    Sanjeev Kumar

    2011-08-01

    Full Text Available Nowadays injection molding is probably the most important method of Processing of consumer and industrial goods, and is performed everywhere in the world. The developing of injection molding becomes a competition from day to day. This Process now integrated with computer control make the production better in quality and Better quantity. The trends of producing a plastics product in injection molding industries are recently changing from traditional method to using the FEA analysis. For injection molding industries, time and cost is very important aspects to consider because these two aspectswill directly related to the profits at a company. The next issue toconsider, to get the best parameter for the injection molding process, plastics has been waste. Through the experiment, operator will use large amount of plastics material to get the possibly parameters to setup the machine.To produce the parts with better quality and quantity these molding defects are the major obstacles in achieving the targets with quality & quantity. Various defects like Short shot, colour streaks and low productivity rates are associated with the material mixing and feeding as molded plastics are often a blend of two or more materials. Colors (master batch and other additives are often mixed (blended with the raw plastic material prior to the molding process in molding plants. So it is very necessary to work out auto blending and auto feeding of plasticgranules to the machine hopper. This paper will cover the studyof automatic blending unit & central conveying system for plasticgranule feeding to machine & will help in optimizing the injection molding process.

  14. Precision lens molding of asphero diffractive surfaces in chalcogenide materials

    Science.gov (United States)

    Nelson, J.; Scordato, M.; Schwertz, K.; Bagwell, J.

    2015-10-01

    Finished lens molding, and the similar process of precision lens molding, have long been practiced for high volume, accurate replication of optical surfaces on oxide glass. The physics surrounding these processes are well understood, and the processes are capable of producing high quality optics with great fidelity. However, several limitations exist due to properties inherent with oxide glasses. Tooling materials that can withstand the severe environmental conditions of oxide glass molding cannot easily be machined to produce complex geometries such as diffractive surfaces, lens arrays, and off axis features. Current machining technologies coupled with a limited selection of tool materials greatly limits the type of structures that can be molded into the finished optic. Tooling for chalcogenide glasses are not bound by these restrictions since the molding temperatures required are much lower than for oxide glasses. Innovations in tooling materials and manufacturing techniques have enabled the production of complex geometries to optical quality specifications and have demonstrated the viability of creating tools for molding diffractive surfaces, off axis features, datums, and arrays. Applications for optics having these features are found in automotive, defense, security, medical, and industrial domains. This paper will discuss results achieved in the study of various molding techniques for the formation of positive diffractive features on a concave spherical surface molded from As2Se3 chalcogenide glass. Examples and results of molding with tools having CTE match with the glass and non CTE match will be reviewed. The formation of stress within the glass during molding will be discussed, and methods of stress management will also be demonstrated and discussed. Results of process development methods and production of good diffractive surfaces will be shown.

  15. Development of a Mold Cracking Simulator: The Study of Breakout and Crack Formation in Continuous Casting Mold

    Science.gov (United States)

    Zhang, Yexin; Wang, Wanlin; Zhang, Haihui

    2016-08-01

    Based on the mold simulator technology, a mold-cracking simulator has been successfully developed to study the process of breakout and the shell surface crack formation during the initial solidification of molten steel inside the continuous casting mold. First, a spheroidal protrusion was installed on the mold hot surface to mimic the abnormal force that generated by mold wall deformation, and then the external force was applied to the initial solidified shell, to facilitate the formation of breakout and shell surface cracks. Second, the responding temperature and heat flux across mold hot surface were recovered by an inverse heat conduction problem. The experimental results indicated that the mold breakout occurs around the shell tip by the combined efforts from external horizontal force, ferrostatic pressure, and thermal stresses during positive strip time. The breakout tends to introduce the peak of the responding temperature and heat flux across the mold hot surface. The vertical propagation velocity of the rupture point in the solidification shell has been calculated as 0.42 m/s in this study, which is in good agreement with industrial slabs. The paper also suggested that surface transverse crack formation is related to the segregation of sulfur during the initial solidification of molten steel.

  16. 21 CFR 133.184 - Roquefort cheese, sheep's milk blue-mold, and blue-mold cheese from sheep's milk.

    Science.gov (United States)

    2010-04-01

    ... surface of the cheese may be scraped to remove surface growth of undesirable microorganisms. One or more... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Roquefort cheese, sheep's milk blue-mold, and blue-mold cheese from sheep's milk. 133.184 Section 133.184 Food and Drugs FOOD AND DRUG...

  17. Development of a new method for the detection of vanadium complexes bound to DNA, using Agarose Gel Electrophoresis

    OpenAIRE

    Subedi, Prabal

    2012-01-01

    Existem apenas alguns métodos disponíveis para o estudo da ligação de metais ao ADN. Estes são baseados em técnicas espectroscópicas, que podem apenas ser utilizadas quando determinados cromóforos quer da molécula de ADN ou dos complexos metálicos estão directamente envolvidos na ligação de metais ao ADN. O objectivo deste projecto foi desenvolver um novo método que pode ser utilizado para detectar a ligação de um metal de transição ao ADN, utilizando Electroforese em gel de agarose (EGA)...

  18. Identifying barriers to billing compliance.

    Science.gov (United States)

    Lorence, Daniel P; Ibrahim, Ibrahim Awad

    2003-01-01

    Programs designed toward the control of health care fraud are leading to increasingly aggressive enforcement and prosecutorial efforts by federal regulators, related to over-reimbursement for service providers. Greater penalties for fraudulent practices have been touted as an effective deterrent to practices that encourage, or fail to prevent, incorrect claims for reimbursement. In such a context, this study sought to examine the extent of compliance management barriers through a national survey of all accredited US health information managers, examining likely barriers to payment of health care claims. Using data from a series of surveys on the stated compliance actions of more than 16,000 health care managers, we find that the publication and dissemination of compliance enforcement regulations had a significant effect on the reduction of fraud. Results further suggest that significant non-adoption of proper billing compliance measures continues to occur, despite the existence of counter-fraud prosecution risk designed to enforce proper compliance. Finally, we identify benchmarks of compliance management and show how they vary across demographic, practice setting, and market characteristics. We find significant variation in influence across practice settings and managed care markets. While greater publicity related to proper billing procedures generally leads to greater compliance awareness, this trend may have created pockets of "institutional non-compliance," which result in an increase in the prevalence of non-compliant management actions. As a more general proposition, we find that it is not sufficient to consider compliance actions independent of institutional or industry-wide influences. PMID:12967244

  19. Synthesis and characterization of macroporous alginate-agarose-magnetite cryobeads for their application in uranium sorption from aqueous medium

    International Nuclear Information System (INIS)

    Contamination of water by heavy metals and radionuclides has become an increasing problem to the environment, which affects the agricultural lands, environmental flora and fauna and importantly human health. There is an interest to develop a simple cost effective technology for the separation of heavy metals from aqueous sub-surfaces. We have developed a novel floating polymeric-magnetite cryobead for the sorption of hexavalent uranium from the aqueous medium. The covalently crosslinked alginate-agarose-magnetite (AAM) cryobeads were synthesized by the process of cryogelation at subzero temperature (i.e. -20 ℃). Alginate polymer was selected for the synthesis of cryobead due to the presence of natural ligand (carboxyl), which interacts with uranyl ions. Agarose was used to provide strength and stability to the cryobeads. Using the AAM cryobeads, we have observed upto 97 % uranium adsorption within 30 min at an initial concentration of 100 mg/L uranium. Due to the macroporous architecture of the cryobeads, the adsorption kinetics was increased 3 folds unlike what has been reported in earlier studies. The study on the effect of pH suggests maximum uranium adsorption (qmax) in the range of 4.5 to 5.5. The thermodynamic parameters i.e. variation in entropy (ΔS), enthalpy (ΔH) and Gibbs free energy (ΔG) were calculated which suggest passive endothermic adsorption behaviour up to 50℃. HCl was found to be an efficient eluent for the uranium desorption. Five repeated cycles for desorption of uranium from biosorbent showed 70 % of uranium recovery. These results suggest stability of novel floating magnetite-cryobeads under acidic conditions and reusability with potential for the recovery of uranium from contaminated aqueous subsurfaces

  20. Evaluation of the friction coefficient, the radial stress, and the damage work during needle insertions into agarose gels.

    Science.gov (United States)

    Urrea, Fabián A; Casanova, Fernando; Orozco, Gustavo A; García, José J

    2016-03-01

    Agarose hydrogels have been extensively used as a phantom material to mimic the mechanical behavior of soft biological tissues, e.g. in studies aimed to analyze needle insertions into the organs producing tissue damage. To better predict the radial stress and damage during needle insertions, this study was aimed to determine the friction coefficient between the material of commercial catheters and hydrogels. The friction coefficient, the tissue damage and the radial stress were evaluated at 0.2, 1.8, and 10mm/s velocities for 28, 30, and 32 gauge needles of outer diameters equal to 0.36, 0.31, and 0.23mm, respectively. Force measurements during needle insertions and retractions on agarose gel samples were used to analyze damage and radial stress. The static friction coefficient (0.295±0.056) was significantly higher than the dynamic (0.255±0.086). The static and dynamic friction coefficients were significantly smaller for the 0.2mm/s velocity compared to those for the other two velocities, and there was no significant difference between the friction coefficients for 1.8 and 10mm/s. Radial stress averages were 131.2±54.1, 248.3±64.2, and 804.9±164.3Pa for the insertion velocity of 0.2, 1.8, and 10mm/s, respectively. The radial stress presented a tendency to increase at higher insertion velocities and needle size, which is consistent with other studies. However, the damage work did not show to be a good predictor of tissue damage, which appears to be due to simplifications in the analytical model. Differently to other approaches, the method proposed here based on radial stress may be extended in future studies to quantity tissue damage in vivo along the entire needle track. PMID:26700572

  1. Quality beyond compliance.

    Science.gov (United States)

    Centanni, N; Monroe, M; White, L; Larson, R

    1999-01-01

    The service sector within the biopharmaceutical industry has experienced phenomenal growth over the past decade. In the highly regulated Good Laboratory Practices environment, the need for timely, high-quality service, accurate results, and on-time deliverables becomes paramount for the success and profitability of biopharmaceutical companies. The quality assurance process is a vital component of this drug product-development cycle and ensures compliance to the highest domestic and international regulatory standards. Quality-assurance professionals historically have held the role of independent auditors of the processes, who certify that results meet current standards of practice. Covance, a contract research organization that includes Good Laboratory Practices laboratories, reorganized and expanded the functional responsibilities of its quality assurance team in 1997. Auditors and quality assurance professionals have assumed roles beyond traditional compliance auditing and are forging new leadership and mentoring roles as process-improvement specialists. The results have been tangible, measurable benefits for clients and the Covance organization. This article provides an overview of this cultural change and the processes put in place to improve efficiency, productivity, and customer and employee satisfaction. PMID:10707374

  2. Star Mapping with Slime Mold Physarum Polycephalum

    Science.gov (United States)

    Mihklepp, M.; Domnitch, E.; Gelfand, D.; Foing, B. H.; van der Heide, E.

    2014-04-01

    Human curiosity and exploration towards outer space has led to many fantastic inventions and given way to alternative scenarios about the origins of life. In the Space Science in the Arts course together with ESTEC with support from ILEWG. I got interested about unicellular slime mold Physarum polycephalum. There has been and still is a lot of research on Physarum polycephalum. This brainless eucaryotic microbe has its smartness and external memory strategies. Physarum can navigate through a maze made of agar using the shortest route possible when two pieces of food are placed at two separate exits of the maze. It can build efficient networks - Physarum created network similar to the existing Tokyo train system. It is being used to control a robot, in USB-sensor and in sound synthesis. Right now there is a lot of research about using Physarum in bio-computing.

  3. Optomechanical details in injection-molded assemblies

    Science.gov (United States)

    Hebert, Raymond T.

    1995-12-01

    With the advent of low-cost electro-optic components such as LEDs, laser diodes and CCD imaging devices, the cost and performance demands now fall upon the optical subsystems in order to achieve realistic marketing targets for many emerging commercial and consumer products. One of the many benefits of injection-molded plastic optics is the diversity of features that are available to the design team. Once designed and incorporated into the tooling, many features are virtually free in high-volume production. These features can include mechanical details as well as optical functions. Registration features can be included for precisely positioning optical elements to one another or to other assemblies such as printed circuit boards or housings. Snaps, compression features, spring-loading elements, standoffs, self-tapping screws or ultrasonically weldable features can greatly facilitate ease of assembly.

  4. Molding Properties and Causes of Deterioration of Recycled Powder Injection Molding Feedstock

    Science.gov (United States)

    Cheng, L. H.; Hwang, K. S.; Fan, Y. L.

    2009-12-01

    To lower the manufacturing cost of powder injection molded products, the gate, runner, sprue, and green parts with defects are usually recycled. Unfortunately, these feedstocks deteriorate as the number of recycling iterations increases. This study presents an investigation of the molding properties and the causes of the deterioration of the recycled feedstocks by monitoring changes in melting points, in-situ strength changes during solvent debinding, spiral length, and viscosity. The oxygen content measurements indicate that serious oxidation occurs after recycling, particularly in the paraffin wax (PW). The results of the molecular weight from gel-permeation chromatography (GPC) also show that the polyethylene (PE) deteriorates during recycling. The viscosity of the 1R (recycled once) feedstock was slightly lower than that of the fresh material. However, as the number of recycling iterations increased, the viscosity increased again. As a result, the spiral length decreased and the required injection pressure increased. It was also noticed that more defects developed along the molding and debinding process.

  5. Replication of optical microlens array using photoresist coated molds.

    Science.gov (United States)

    Chakrabarti, M; Dam-Hansen, C; Stubager, J; Pedersen, T F; Pedersen, H C

    2016-05-01

    A cost reduced method of producing injection molding tools is reported and demonstrated for the fabrication of optical microlens arrays. A standard computer-numerical-control (CNC) milling machine was used to make a rough mold in steel. Surface treatment of the steel mold by spray coating with photoresist is used to smooth the mold surface providing good optical quality. The tool and process are demonstrated for the fabrication of an ø50 mm beam homogenizer for a color mixing LED light engine. The acceptance angle of the microlens array is optimized, in order to maximize the optical efficiency from the light engine. Polymer injection molded microlens arrays were produced from both the rough and coated molds and have been characterized for lenslet parameters, surface quality, light scattering, and acceptance angle. The surface roughness (Ra) is improved approximately by a factor of two after the coating process and the light scattering is reduced so that the molded microlens array can be used for the color mixing application. The measured accepted angle of the microlens array is 40° which is in agreement with simulations. PMID:27137566

  6. Thermomechanical Behavior in Continuous Bloom Casting with Different Mold Tapers

    Institute of Scientific and Technical Information of China (English)

    LUO Xin; CHEN Yong; SHEN Houfa

    2008-01-01

    A two-dimensional finite element model was used to analyze the thermal and mechanical behavior dunng solidification of the strand in a continuous bloom casting mold.The coupled heat transfer and defermation were analyzed to simulate the formation of the air gap between the mold and the strand.The model was used to investigate the influence of mold taper on the temperature and stress distributions in the strand.The results show that the air gap mainly forms around the strand corner,causing a hoRer and thinner solidifying shell in this region.The mold taper partially compensates for the strand shell shnnkage and reduces the infiuence of the air gap on the heat transfer.The mold taper compresses the shell and changes the stress state around the stmnd comer region.As the strand moves down into the mold,the mold constraint causes compressive stress beneath the comer surface.which reduces the hot tear that forms on the strand.

  7. Interface conditions of two-shot molded parts

    Energy Technology Data Exchange (ETDEWEB)

    Kisslinger, Thomas, E-mail: thomas.kisslinger@pccl.at [Polymer Competence Center Leoben GmbH, 8700 Leoben (Austria); Bruckmoser, Katharina, E-mail: katharina.bruckmoser@unileoben.ac.at; Resch, Katharina, E-mail: katharina.resch@unileoben.ac.at [Department of Polymer Engineering and Science, Chair of Materials Science and Testing of Polymers, Montanuniversitaet Leoben, 8700 Leoben (Austria); Lucyshyn, Thomas, E-mail: thomas.lucyshyn@unileoben.ac.at, E-mail: guenter.langecker@unileoben.ac.at; Langecker, Guenter Ruediger, E-mail: thomas.lucyshyn@unileoben.ac.at, E-mail: guenter.langecker@unileoben.ac.at; Holzer, Clemens, E-mail: clemens.holzer@unileoben.ac.at [Department of Polymer Engineering and Science, Chair of Polymer Processing, Montanuniversitaet Leoben, 8700 Leoben (Austria)

    2014-05-15

    The focus of this work is on interfaces of two-shot molded parts. It is well known that e.g. material combination, process parameters and contact area structures show significant effects on the bond strength of multi-component injection molded parts. To get information about the bond strength at various process parameter settings and material combinations a test mold with core back technology was used to produce two-component injection molded tensile test specimens. At the core back process the different materials are injected consecutively, so each component runs through the whole injection molding cycle (two-shot process). Due to this consecutive injection molding processes, a cold interface is generated. This is defined as overmolding of a second melt to a solidified polymer preform. Strong interest lies in the way the interface conditions change during the adhesion formation between the individual components. Hence the interface conditions were investigated by computed tomography and Raman spectroscopy. By analyzing these conditions the understanding of the adhesion development during the multi-component injection molding was improved.

  8. Injection molded dielectromagnets prepared from mixture of hard magnetic powders

    International Nuclear Information System (INIS)

    Dielectromagnets are permanent magnets prepared from a hard magnetic powder bonded by binder. These permanent magnets are termed also as bonded permanent magnets. There are two ways to prepare dielectromagnets: compression molding and injection molding. Dielectromagnets prepared by injection molding, from the same hard magnetic powders, have worse magnetic properties than dielectromagnets prepared by compression molding, but they are cheaper. Isotropic dielectromagnets prepared from ferrite powder have low value of magnetic properties, but their advantage is positive value of temperature coefficient of JHc. They are low in price. Dielectromagnets prepared from melt-spun Nd-Fe-B have high values of magnetic properties.Value of temperature coefficient of JHc is their weakness. They are more expensive than ferrite dielectromagnets. Comparison of advantages and disadvantages of dielectromagnets prepared from different kinds of hard magnetic powder has produced an idea of making dielectromagnets from the mixture of these powders prepared by compression molding have magnetic and thermal properties of values between values of dielectromagnets from Nd-Fe-B and ferrite powders. It was described elsewhere. The purpose of this investigation is to prepare injection molded dielectromagnets from mixture of powders of strontium ferrite and melt-spun ribbon Nd-Fe-B and to find correlation between the composition of the mixture and magnetic properties of dielectromagnets. A result of mixture composition on magnetic properties of injection molded dielectromagnets is shown. (author)

  9. Separation of human IgG fragments using copper, nickel, zinc, and cobalt chelated to CM-Asp-agarose by positive and negative chromatography.

    Science.gov (United States)

    Mourão, Cecília Alves; Carmignotto, Gabriela Pannunzio; Bueno, Sonia Maria Alves

    2016-04-01

    This study evaluated the feasibility of using immobilized metal-ion affinity chromatography (IMAC) for separation of human Fab fragments using four different transition metal ions copper, nickel, zinc, and cobalt chelated to CM-Asp (carboxymethylaspartate) immobilized on the agarose gel. The Fab and Fc fragments (from human IgG digested with papain) interacted differently with the chelates studied, depending on the adsorption buffer system. The interaction between chelate and Fc fragment is predominantly based on the coordination bonds using adsorption buffer containing NaCl. Negative chromatography was performed on Cu(II)-CM-Asp-agarose obtaining 2.9mg of Fab per mL of adsorbent in nonretained fractions (Fc fragment-free without uncleaved IgG). The adsorption of Fab fragments is governed by electrostatic forces in the absence of NaCl in the adsorption buffer. High selectivity was achieved on Co(II)-CM-Asp-agarose and 5.7mg of Fab per mL of adsorbent was obtained in eluted fractions without Fc fragments, although having uncleaved IgG. The results showed that chromatography on transition metal ions chetated to CM-Asp-agarose is a promising approach to separation of Fab fragments from papain-digested human IgG solution. PMID:26974869

  10. Automatic polishing process of plastic injection molds on a 5-axis milling center

    CERN Document Server

    Pessoles, Xavier; 10.1016/j.jmatprotec.2008.08.034

    2010-01-01

    The plastic injection mold manufacturing process includes polishing operations when surface roughness is critical or mirror effect is required to produce transparent parts. This polishing operation is mainly carried out manually by skilled workers of subcontractor companies. In this paper, we propose an automatic polishing technique on a 5-axis milling center in order to use the same means of production from machining to polishing and reduce the costs. We develop special algorithms to compute 5-axis cutter locations on free-form cavities in order to imitate the skills of the workers. These are based on both filling curves and trochoidal curves. The polishing force is ensured by the compliance of the passive tool itself and set-up by calibration between displacement and force based on a force sensor. The compliance of the tool helps to avoid kinematical error effects on the part during 5-axis tool movements. The effectiveness of the method in terms of the surface roughness quality and the simplicity of impleme...

  11. The Strategic Nature of Compliance

    DEFF Research Database (Denmark)

    König, Thomas; Mäder, Lars Kai

    2014-01-01

    ) is praised for exemplary effectiveness, but our findings reveal that the monitoring agency refrains from enforcing compliance when the probability of success is low, and the sanctioning costs are high. This results in a compliance deficit, even though the selective enforcement activities of the...

  12. 40 CFR 68.79 - Compliance audits.

    Science.gov (United States)

    2010-07-01

    ... are being followed. (b) The compliance audit shall be conducted by at least one person knowledgeable... compliance audit, and document that deficiencies have been corrected. (e) The owner or operator shall retain the two (2) most recent compliance audit reports....

  13. Compliance with Segment Disclosure Initiatives

    DEFF Research Database (Denmark)

    Arya, Anil; Frimor, Hans; Mittendorf, Brian

    2013-01-01

    Regulatory oversight of capital markets has intensified in recent years, with a particular emphasis on expanding financial transparency. A notable instance is efforts by the Financial Accounting Standards Board that push firms to identify and report performance of individual business units...... (segments). This paper seeks to address short-run and long-run consequences of stringent enforcement of and uniform compliance with these segment disclosure standards. To do so, we develop a parsimonious model wherein a regulatory agency promulgates disclosure standards and either permits voluntary...... compliance or mandates strict compliance from firms. Under voluntary compliance, a firm is able to credibly withhold individual segment information from its competitors by disclosing data only at the aggregate firm level. Consistent with regulatory hopes, we show that mandatory compliance enhances welfare...

  14. Two component micro injection molding for MID fabrication

    DEFF Research Database (Denmark)

    Islam, Mohammad Aminul; Hansen, Hans Nørgaard; Tang, Peter Torben

    2009-01-01

    Molded Interconnect Devices (MIDs) are plastic substrates with electrical infrastructure. The fabrication of MIDs is usually based on injection molding and different process chains may be identified from this starting point. The use of MIDs has been driven primarily by the automotive sector......, but recently the medical sector seems more and more interested. In particular the possibility of miniaturization of 3D components with electrical infrastructure is attractive. The paper describes possible manufacturing routes and challenges of miniaturized MIDs based on two component micro injection molding...

  15. Development of Integrated Simulation System for Plastic Injection Molding

    Institute of Scientific and Technical Information of China (English)

    CHENGXue-wen; LIDe-qun; ZHOUHua-min

    2005-01-01

    Numerical simulation of injection molding have had success in predicting the behavior of polymer melt in extremely complicated geometries. Most of the current numerical solutions are based on finite-element/finite-difference/boundary-element/volume-control methods and the surface model. This paper discusses the development of an integrated CAE system for injection molding in detail, and presents the mathematics for numerical simulation of filling, packing,cooling, stress and warpage in injection molding. The developed system named as HsCAE3D is introduced at the end.

  16. Fabrication of sinterable silicon nitride by injection molding

    Science.gov (United States)

    Quackenbush, C. L.; French, K.; Neil, J. T.

    1982-01-01

    Transformation of structural ceramics from the laboratory to production requires development of near net shape fabrication techniques which minimize finish grinding. One potential technique for producing large quantities of complex-shaped parts at a low cost, and microstructure of sintered silicon nitride fabricated by injection molding is discussed and compared to data generated from isostatically dry-pressed material. Binder selection methodology, compounding of ceramic and binder components, injection molding techniques, and problems in binder removal are discussed. Strength, oxidation resistance, and microstructure of sintered silicon nitride fabricated by injection molding is discussed and compared to data generated from isostatically dry-pressed material.

  17. Fabrication of micro gear wheels by micropowder injection molding

    Institute of Scientific and Technical Information of China (English)

    Haiqing Yin; Xuanhui Qu; Chengchang Jia

    2008-01-01

    The micropowder injection molding technology was investigated to fabricate the microsized gear wheels on a conventional injection molding machine. The feedstock comprised of carbonyl ferrum powder and a wax-based thermoplastic binder. Microinjection molding was fulfilled at about 423 K under 100 MPa. The heating system was applied to the die to improve the fluidity of the feedstock and subsequently the cooling system was used to enhance the strength of the green compacts after injection by decreasing the temperature of the die. The gear wheels were realized successfully with their addendum circle diameter ranging from 800 to 200 m and with the center hole as small as 60 μtm.

  18. Recent Developments and Trends in Powder Injection Molding

    Institute of Scientific and Technical Information of China (English)

    Hermina Wang

    2000-01-01

    Injection molding is a productive and widely used technology for shaping plastics. The use of this shaping technique to metal and ceramics powders is termed powder injection molding (PIM). This process combines a certain quantity of a polymer with a metallic or ceramic powder to form a feedstock that can be molded. After shaping, the polymeric binder is extracted and the powder is sintered. When proper powder size or/and its distribution are used, sintered densities of 95% or more, often to near-theoretical densities, are reached and the mechanical properties are, therefore, generally superior to those of traditional PM parts.

  19. A New Type Machine of Mixing-molding for Polyblends

    Institute of Scientific and Technical Information of China (English)

    WANG Chuan-sheng; LI Li; BIAN Hui-guang

    2009-01-01

    This paper introduces a new type machine for polyblends with excellent mixing capabilities of internal mixer and continuous molding character of extruder. The machine includes two functions -- mixing and extrusion molding that have been composed together by rational design, so a tandem production mode -- "batch + continuous" are opened up. The mathematical model of continuous mixing molding was established and verified availably by experimental research. The main physical mechanical property of vuicanizate, which had met national waterproof material standard, verified the machine practicability. The essential difference from other similar type machines is that this machine is not only suitable in producing granular and powder rubbers but also lumpish tablets.

  20. Bench mark test casting: Modeling of mold filling and solidification

    Energy Technology Data Exchange (ETDEWEB)

    Layton, M.A.; Wang, C.M.; Cheng, C.; Yu, K.O.; Paul, A.J. [Concurrent Technologies Corp., Johnstown, PA (United States)

    1995-12-31

    This paper presents the results of simulating the mold filling and solidification of an aluminum plate casting designed as the Bench Mark Test Casting for this conference. An in-house simulation software, RAPID/CAST{reg_sign}, has been used to conduct this simulation. The output of this simulation include flow front location during mold filling, cooling curves at various points in the casting, temperature distribution, and isochron plots of solidification times. The simulation results indicate that the mold filling time of the entire casting is 2.2 seconds and that the last region to solidify is located around the ingate.

  1. Environmental compliance assessment review

    International Nuclear Information System (INIS)

    During the period 1972-1991, The United States Congress passed stringent environmental statues which the Environment Protection Agency implemented via regulations. The statues and regulations contain severe civil and criminal penalties. Civil violations resulted in fines, typically payable by the company. The act of willfully and knowingly violating the permit conditions or regulations can result in criminal charges being imposed upon the responsible part, i.e., either the company or individual. Criminal charges can include fines, lawyer fees, court costs and incarceration. This paper describes steps necessary to form an effective Environmental Compliance Assessment Review [CAR] program, train field and engineering personnel and perform a CAR audit. Additionally, the paper discusses the findings of a number of Exploration and Production [E and P] field audits

  2. A review on the importance of surface coating of micro/nano-mold in micro/nano-molding processes

    Science.gov (United States)

    Saha, Biswajit; Toh, Wei Quan; Liu, Erjia; Beng Tor, Shu; Hardt, David E.; Lee, Junghoon

    2016-01-01

    Micro/nano hot-embossing and injection molding are two promising manufacturing processes for the mass production of workpieces bearing micro/nanoscale features. However, both the workpiece and micro/nano-mold are susceptive to structural damage due to high thermal stress, adhesion and friction, which occur at the interface between the workpiece and the mold during these processes. Hence, major constraints of micro/nano-molds are mainly attributed to improper replication and their inability to withstand a prolonged sliding surface contact because of high sidewall friction and/or high adhesion. Consequently, there is a need for proper surface coating as it can improve the surface properties of micro/nano-molds such as having a low friction coefficient, low adhesion and low wear rate. This review deals with the physical, mechanical and tribological properties of various surface coatings and their impact on the replication efficiency and lifetime of micro/nano-molds that are used in micro/nano hot-embossing and injection molding processes.

  3. Rapid and low-cost prototyping of medical devices using 3D printed molds for liquid injection molding.

    Science.gov (United States)

    Chung, Philip; Heller, J Alex; Etemadi, Mozziyar; Ottoson, Paige E; Liu, Jonathan A; Rand, Larry; Roy, Shuvo

    2014-01-01

    Biologically inert elastomers such as silicone are favorable materials for medical device fabrication, but forming and curing these elastomers using traditional liquid injection molding processes can be an expensive process due to tooling and equipment costs. As a result, it has traditionally been impractical to use liquid injection molding for low-cost, rapid prototyping applications. We have devised a method for rapid and low-cost production of liquid elastomer injection molded devices that utilizes fused deposition modeling 3D printers for mold design and a modified desiccator as an injection system. Low costs and rapid turnaround time in this technique lower the barrier to iteratively designing and prototyping complex elastomer devices. Furthermore, CAD models developed in this process can be later adapted for metal mold tooling design, enabling an easy transition to a traditional injection molding process. We have used this technique to manufacture intravaginal probes involving complex geometries, as well as overmolding over metal parts, using tools commonly available within an academic research laboratory. However, this technique can be easily adapted to create liquid injection molded devices for many other applications. PMID:24998993

  4. A review on the importance of surface coating of micro/nano-mold in micro/nano-molding processes

    International Nuclear Information System (INIS)

    Micro/nano hot-embossing and injection molding are two promising manufacturing processes for the mass production of workpieces bearing micro/nanoscale features. However, both the workpiece and micro/nano-mold are susceptive to structural damage due to high thermal stress, adhesion and friction, which occur at the interface between the workpiece and the mold during these processes. Hence, major constraints of micro/nano-molds are mainly attributed to improper replication and their inability to withstand a prolonged sliding surface contact because of high sidewall friction and/or high adhesion. Consequently, there is a need for proper surface coating as it can improve the surface properties of micro/nano-molds such as having a low friction coefficient, low adhesion and low wear rate. This review deals with the physical, mechanical and tribological properties of various surface coatings and their impact on the replication efficiency and lifetime of micro/nano-molds that are used in micro/nano hot-embossing and injection molding processes. (topical review)

  5. 40 CFR 63.5728 - What standards must I meet for closed molding resin operations?

    Science.gov (United States)

    2010-07-01

    ... molding resin operations? 63.5728 Section 63.5728 Protection of Environment ENVIRONMENTAL PROTECTION... Standards for Closed Molding Resin Operations § 63.5728 What standards must I meet for closed molding resin operations? (a) If a resin application operation meets the definition of closed molding specified in §...

  6. The use of birefringence for predicting the stiffness of injection molded polycarbonate discs

    NARCIS (Netherlands)

    Neves, N.M.; Pouzada, A.S.; Voerman, J.H.D.; Powell, P.C.

    1998-01-01

    Polycarbonate discs were injection molded with different sets of molding conditions. The parameters studied were the flow rate, melt- and mold-temperature. The discs were subjected to three point support flexural tests. Those tests are specially intended for injection molded discs because of their i

  7. INVESTIGATION OF THE INFLUENCE OF MOLD ROTATIONAL SPEED ON THE CAST WALL THICKNESS IN THE ROTATIONAL MOLDING PROCESS

    Directory of Open Access Journals (Sweden)

    Tomasz Jachowicz

    2013-09-01

    Full Text Available This paper presents the rotational molding process. The general principles of this polymer processing technology have been described. The main applications have been introduced and leading advantages and typical disadvantages of rotational molding process have been discussed. Based on the conducted experimental tests, the influence of changing one selected technological parameter, which characterized rotational molding process, on selected geometrical features of the polymer cast has been determined. Rotational mold’s speed around axes was changed and a thickness of cast walls has been measured. Laboratory test stand, processing properties of polymer, also test program and experimental test methodology have been described.

  8. Evolution of Surface Texture and Cracks During Injection Molding of Fiber-Reinforced, Additively-Manufactured, Injection Molding Inserts

    DEFF Research Database (Denmark)

    Hofstätter, Thomas; Mischkot, Michael; Pedersen, David Bue;

    2016-01-01

    This paper investigates the lifetime and surfacedeterioration of additively-manufactured, injection-moulding inserts. The inserts were produced using digital light processing and were reinforcedwith oriented short carbon fibers. Theinserts were used during injection molding oflow-density polyethy......-density polyethylene until their failure. The molded products were used to analyse the development of the surface roughness and wear. By enhancing the lifetime of injection-molding inserts,this work contributes to the establishment of additively manufactured inserts in pilot production....

  9. Cork is used to make tooling patterns and molds

    Science.gov (United States)

    Hoffman, F. J.

    1965-01-01

    Sheet and waste cork are cemented together to provide a tooling pattern or mold. The cork form withstands moderately high temperatures under vacuum or pressure with minimum expansion, shrinkage, or distortion.

  10. Research on machine vision system of monitoring injection molding processing

    Science.gov (United States)

    Bai, Fan; Zheng, Huifeng; Wang, Yuebing; Wang, Cheng; Liao, Si'an

    2016-01-01

    With the wide development of injection molding process, the embedded monitoring system based on machine vision has been developed to automatically monitoring abnormality of injection molding processing. First, the construction of hardware system and embedded software system were designed. Then camera calibration was carried on to establish the accurate model of the camera to correct distortion. Next the segmentation algorithm was applied to extract the monitored objects of the injection molding process system. The realization procedure of system included the initialization, process monitoring and product detail detection. Finally the experiment results were analyzed including the detection rate of kinds of the abnormality. The system could realize the multi-zone monitoring and product detail detection of injection molding process with high accuracy and good stability.

  11. Residual stresses in injection molded shape memory polymer parts

    Science.gov (United States)

    Katmer, Sukran; Esen, Huseyin; Karatas, Cetin

    2016-03-01

    Shape memory polymers (SMPs) are materials which have shape memory effect (SME). SME is a property which has the ability to change shape when induced by a stimulator such as temperature, moisture, pH, electric current, magnetic field, light, etc. A process, known as programming, is applied to SMP parts in order to alter them from their permanent shape to their temporary shape. In this study we investigated effects of injection molding and programming processes on residual stresses in molded thermoplastic polyurethane shape memory polymer, experimentally. The residual stresses were measured by layer removal method. The study shows that injection molding and programming process conditions have significantly influence on residual stresses in molded shape memory polyurethane parts.

  12. Method and mold for casting thin metal objects

    Energy Technology Data Exchange (ETDEWEB)

    Pehrson, Brandon P; Moore, Alan F

    2014-04-29

    Provided herein are various embodiments of systems for casting thin metal plates and sheets. Typical embodiments include layers of mold cavities that are oriented vertically for casting the metal plates. In some embodiments, the mold cavities include a beveled edge such that the plates that are cast have a beveled edge. In some embodiments, the mold cavities are filled with a molten metal through an open horizontal edge of the cavity. In some embodiments, the mold cavities are filled through one or more vertical feed orifices. Further disclosed are methods for forming a thin cast metal plate or sheet where the thickness of the cast part is in a range from 0.005 inches to 0.2 inches, and the surface area of the cast part is in a range from 16 square inches to 144 square inches.

  13. Moldability Evaluation for Molded Parts Based on Fuzzy Reasoning

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Moldability evaluation for molded parts, which is the basis of concurrent design, is a key design stage in injection molding design. By moldability evaluation the design problems can be found timely and an optimum plastic part design achieved. In this paper, a systematic methodology for moldability evaluation based on fuzzy logic is proposed. Firstly, fuzzy set modeling for six key design attributes of molded parts is carried out respectively. Secondly, on the basis of this, the relationship between fuzzy sets for design attributes and fuzzy sets for moldability is established by fuzzy rules that are based on domain experts' experience and knowledge. At last the integral moldability for molded parts is obtained through fuzzy reasoning. The neural network based fuzzy reasoning approach presented in this paper can improve fuzzy reasoning efficiency greatly, especially for system having a large number of rules and complicated membership functions. An example for moldability evaluation is given to show the feasibility of this proposed methodology.

  14. Mold Heating and Cooling Pump Package Operator Interface Controls Upgrade

    Energy Technology Data Exchange (ETDEWEB)

    Josh A. Salmond

    2009-08-07

    The modernization of the Mold Heating and Cooling Pump Package Operator Interface (MHC PP OI) consisted of upgrading the antiquated single board computer with a proprietary operating system to off-the-shelf hardware and off-the-shelf software with customizable software options. The pump package is the machine interface between a central heating and cooling system that pumps heat transfer fluid through an injection or compression mold base on a local plastic molding machine. The operator interface provides the intelligent means of controlling this pumping process. Strict temperature control of a mold allows the production of high quality parts with tight tolerances and low residual stresses. The products fabricated are used on multiple programs.

  15. Development and Characterization of a Metal Injection Molding Bio Sourced Inconel 718 Feedstock Based on Polyhydroxyalkanoates

    OpenAIRE

    Alexandre Royer; Thierry Barrière; Jean-Claude Gelin

    2016-01-01

    The binder plays the most important role in the metal injection molding (MIM) process. It provides fluidity of the feedstock mixture and adhesion of the powder to keep the molded shape during injection molding. The binder must provide strength and cohesion for the molded part and must be easy to remove from the molded part. Moreover, it must be recyclable, environmentally friendly and economical. Also, the miscibility between polymers affects the homogeneity of the injected parts. The goal of...

  16. Biological Control of Olive Green Mold in Agaricus bisporus Cultivation

    OpenAIRE

    Tautorus, T. E.; Townsley, P. M.

    1983-01-01

    Successful methods to control the damaging weed mold Chaetomium olivaceum (olive green mold) in mushroom beds are not presently known. An attempt was made to control C. olivaceum by biological means. A thermophilic Bacillus sp. which showed dramatic activity against C. olivaceum on Trypticase soy agar (BBL Microbiology Systems)-0.4% yeast extract agar plates was isolated from commercial mushroom compost (phase I). When inoculated into conventional and hydroponic mushroom beds, the bacillus no...

  17. Fabrication and properties of binder for powder extrusion molding

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    By optimizing formulation and fabrication methods, a new binder for plasticizing powder extrusion molding ofhard metal, with excellent integrated properties and uniform distribution characters, has been developed. Thermal debond-ing mechanism and the extruding rheological behaviours have been studied. The technology of fabrication of binder andthermal debonding process have also been investigated. Using the novel binder, the hard-metal extrusion-molding rods withdiameter up to 25mm, have been manufactured.

  18. Evaluation of Additive Manufacturing for Composite Part Molds

    Energy Technology Data Exchange (ETDEWEB)

    Duty, Chad E. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Springfield, Robert M. [Tru Design, LLC, Knoxville, TN (United States)

    2015-02-01

    The ORNL Manufacturing Demonstration Facility (MDF) collaborated with Tru-Design to test the quality and durability of molds used for making fiber reinforced composites using additive manufacturing. The partners developed surface treatment techniques including epoxy coatings and machining to improve the quality of the surface finish. Test samples made using the printed and surface finished molds demonstrated life spans suitable for one-of-a-kind and low-volume applications, meeting the project objective.

  19. The Simulation and Optimization of Aspheric Plastic Lens Injection Molding

    Institute of Scientific and Technical Information of China (English)

    WEN Jialing; WEN Pengfei

    2005-01-01

    For the purpose of reducing the volumetric shrinkage and volumetric shrinkage variation, the process in injection molding of aspheric plastic lens was simulated, and several process parameters which include holding pressure, melt temperature, mold temperature, fill time, holding pressure time and cooling time were optimized by using an orthogonal experimental design method. Finally, the optimum process parameters and the influence degree of process parameters on the average volumetric shrinkage and the volumetric shrinkage variation are obtained.

  20. A Recurrent Neural Network for Warpage Prediction in Injection Molding

    OpenAIRE

    A. Alvarado-Iniesta; D.J. Valles-Rosales; J.L. García-Alcaraz; A. Maldonado-Macias

    2012-01-01

    Injection molding is classified as one of the most flexible and economical manufacturing processes with high volumeof plastic molded parts. Causes of variations in the process are related to the vast number of factors acting during aregular production run, which directly impacts the quality of final products. A common quality trouble in finishedproducts is the presence of warpage. Thus, this study aimed to design a system based on recurrent neural networksto predict warpage defects in product...

  1. Localized rapid heating process for precision chalcogenide glass molding

    Science.gov (United States)

    Li, Hui; He, Peng; Yu, Jianfeng; Lee, L. James; Yi, Allen Y.

    2015-10-01

    Precision glass molding is an important process for high volume optical fabrication. However, conventional glass molding is a bulk heating process that usually requires a long thermal cycle, where molding assembly and other mechanical parts are heated and cooled together. This often causes low efficiency and other heating and cooling related problems, such as large thermal expansion in both the molds and molded optics. To cope with this issue, we developed a localized rapid heating process to effectively heat only very small part of the glass. This localized rapid heating study utilized a fused silica wafer coated with a thin graphene layer to heat only the surface of the glass. The graphene coating functions as an electrical resistant heater when a power source was applied across the thin film coating, generating heat on and near the coating. The feasibility of this process was validated by both experiments and numerical simulation. To demonstrate the advantages of the localized rapid heating, both localized rapid heating process and bulk heating process were performed and carefully compared. The uniformity and quality of the molded sample by localized rapid heating process was also demonstrated. In summary, localized rapid heating process by using graphene coated fused silica wafer was characterized and can be readily implemented in replication of micro scale chalcogenide glasses. A fused silica wafer coated with a thin graphene layer was utilized for localized rapid heating only the surface of the glass. The graphene coating functions as an electrical resistant heater when a power source was applied across the thin film coating, generating high temperature on and near the coating. This process is fast and efficient since only interested areas are heated without affecting the entire glass substrate or the mold assembly. The uniformity and quality of the molded sample by localized rapid heating process was demonstrated by comparing both localized rapid heating

  2. Prediction of Mold Spoilage for Soy/Polyethylene Composite Fibers

    Directory of Open Access Journals (Sweden)

    Chinmay Naphade

    2015-01-01

    Full Text Available Mold spoilage was determined over 109 days on soy/PE fibers held under controlled temperatures (T ranging from 10°C to 40°C and water activities (aw from 0.11 to 0.98. Water activities were created in sealed containers using saturated salt solutions and placed in temperature-controlled incubators. Soy/PE fibers that were held at 0.823 aw or higher exhibited mold growth at all temperatures. As postulated, increased water activity (greater than 0.89 and temperature (higher than 25°C accelerated mold growth on soy/PE fibers. A slower mold growth was observed on soy/PE fibers that were held at 0.87 aw and 10°C. A Weibull model was employed to fit the observed logarithmic values of T, aw, and an interaction term log⁡T×log⁡aw and was chosen as the final model as it gave the best fit to the raw mold growth data. These growth models predict the expected mold-free storage period of soy/PE fibers when exposed to various environmental temperatures and humidities.

  3. Frequency of Mold Allergens in Allergic Rhinitis Patients

    Directory of Open Access Journals (Sweden)

    Bonyadi, MR. (PhD

    2014-06-01

    Full Text Available Background and Objective: Allergic rhinitis can be stimulated by several allergens. Molds are among these allergens and it is important to assess their frequency in different geographic area. Hence, we aimed at determining the frequency of mold allergens in allergic rhinitis patients referred to specialized clinics of Tabriz Imam Reza hospital, 2011. Material and Methods: This cross-sectional study was conducted on the serums of 90 rhinitis patients diagnosed by specialized physician. Using Immunoblotting method, the level of specific IgE against four molds including Penicillium, Aspergillus, Alternaria and Cladosporium were investigated. Results: Of 90 Patients, 40 were men (44.4% and 50 were women (55.6%. The participants were between 6 to 53 years and the most were 28-31years. The allergy was related to Penicillium (3.3%, Aspergillus (5.6%, Alternaria (13.3% and Cladosporium (4.4%. There was a significant statistical relation between age and allergic rhinitis to Alternaria (P=0.011. Conclusion: Molds can grow and proliferate in very humid environments. Because of low humidity climate in Tabriz (in the northwest of Iran, allergy to molds is relatively low in this region. Key words: Rhinitis Allergic; Mold; Allergy

  4. Precision glass molding of high-resolution diffractive optical elements

    Science.gov (United States)

    Prater, Karin; Dukwen, Julia; Scharf, Toralf; Herzig, Hans P.; Plöger, Sven; Hermerschmidt, Andreas

    2016-04-01

    The demand of high resolution diffractive optical elements (DOE) is growing. Smaller critical dimensions allow higher deflection angles and can fulfill more demanding requirements, which can only be met by using electron-beam lithography. Replication techniques are more economical, since the high cost of the master can be distributed among a larger number of replicas. The lack of a suitable mold material for precision glass molding has so far prevented an industrial use. Glassy Carbon (GC) offers a high mechanical strength and high thermal strength. No anti-adhesion coatings are required in molding processes. This is clearly an advantage for high resolution, high aspect ratio microstructures, where a coating with a thickness between 10 nm and 200 nm would cause a noticeable rounding of the features. Electron-beam lithography was used to fabricate GC molds with highest precision and feature sizes from 250 nm to 2 μm. The master stamps were used for precision glass molding of a low Tg glass L-BAL42 from OHARA. The profile of the replicated glass is compared to the mold with the help of SEM images. This allows discussion of the max. aspect-ratio and min. feature size. To characterize optical performances, beamsplitting elements are fabricated and their characteristics were investigated, which are in excellent agreement to theory.

  5. Numerical Simulation of Mold Filling in Resin Transfer Molding Using Isoparametric Method

    Institute of Scientific and Technical Information of China (English)

    ZHANG Kaipeng; TAN Hua; WANG Jihui; ZHU Yingdan

    2005-01-01

    The mold filling of RTM was simulated based on the control volume finite element method (CV/FEM). The formulation using isoparametric transformation was discussed in detail and a computational code based on isoparametric technique was developed. The simulation results were compared with experimental data. Different isoparametric elements, quadrilateral and triangular, were compared in the simulation.It demonstrates that the use of bilinear quadrilateral isoparametric elements in simulating the process can produce a higher precision and cost a less time than the use of triangular ones.

  6. Development of mold for biodegradable materials

    Energy Technology Data Exchange (ETDEWEB)

    Japitana, F.H.; Jabrica, A.M. [Metals Industry Research and Develeopment Center, Manila (Philippines). Dept. of Science and Technology; Komatsu, M. [Komatsu Consulting Engineer Office, Iwaki City, Fukushima (Japan); Takeuchi, Y. [Osaka Univ., Osaka (Japan). Dept. of Mechanical Engineering

    2008-07-01

    The improper disposal of non-biodegradable plastics adversely affect global environmental factors, principles of sustainability, industrial ecology and ecoefficiency. Therefore, a new generation of bio-based polymeric products has been developed. These polylactides (PLA), cellulose esters, starch plastics and polyhydroxyalkanoates (PHAs) are made from renewable natural resources and are biodegradable. They meet environmental conditions and can compete with their petrochemical counterparts. Among them, PLA is particularly attractive as a sustainable alternative to synthetic polymers and a potential candidate for the fabrication of biocomposites. Certain blends have proved successful in medical implants, sutures and drug delivery systems because of their capacity to dissolve away with time. However, widespread use of PLA is limited because of cost. Biodegradable plastic products are currently 6 to 10 times more expensive than traditional plastics. Environmentalists argue that the cheaper price of traditional plastics does not reflect their true cost when their impact is considered. This paper presented a solution to reduce the production cost of biodegradable plastics. In particular, it described a newly developed plastic injection mold for biodegradable materials which can produce a scrapless product. The system reduces processing time because it is not necessary to remove any gating or runners after the injection process. Takeout robots ensure that the quality of the product is maintained. 12 figs.

  7. Determination of heat transfer coefficients at the polymer-mold-interface for injection molding simulation by means of calorimetry

    Science.gov (United States)

    Stricker, M.; Steinbichler, G.

    2014-05-01

    Appropriate modeling of heat transfer from the polymer material to the injection mold is essential to achieve accurate simulation results. The heat transfer is commonly modeled using convective heat transfer and applying heat transfer coefficients (HTC) to the polymer-mold-interface. The set HTC has an influence on the results for filling pressure, cooling performance and shrinkage, among others. The current paper, presents a new strategy to measure HTC in injection molding experiments using Newtons law of cooling. The heat flux is calculated out of demolding heat (measured by means of calorimetry), injection heat (measured by means of an IR-sensor), cooling time and part mass. Cavity surface area, average mold surface temperature and average part surface temperature lead to the HTC.

  8. Investigation of Heat Transfer at the Mold/Metal Interface in Permanent Mold Casting of Light Alloys

    Energy Technology Data Exchange (ETDEWEB)

    Robert D. Pehlke; John T. Berry

    2005-12-16

    Accurate modeling of the metal casting process prior to creating a mold design demands reliable knowledge of the interfacial heat transfer coefficient at the mold metal interface as a function of both time and location. The phenomena concerned with the gap forming between the mold and the solidifying metal are complex but need to be understood before any modeling is attempted. The presence of mold coatings further complicates the situation. A commercial casting was chosen and studied in a gravity permanent mold casting process. The metal/mold interfacial heat transfer coefficient (IHTC) was the focus of the research. A simple, direct method has been used to evaluate the IHTC. Both the simulation and experiments have shown that a reasonably good estimate of the heat transfer coefficient could be made in the case studied. It has been found that there is a good agreement between experiments and simulations in the temperature profiles during the solidification process, given that the primary mechanism of heat transfer across the gap in permanent mold casting of light alloys is by conduction across the gap. The procedure utilized to determine the interfacial heat transfer coefficient can be applied to other casting processes. A recently completed project involving The University of Michigan and Mississippi State University, together with several industrial partners, which was supported by the USDOE through the Cast Metals Coalition, examined a number of cases of thermal contact. In an investigation which gave special consideration to the techniques of measurement, several mold coatings were employed and results presented as a function of time. Realistic conditions of coating thickness and type together with an appropriate combination of mold preheat and metal pouring temperature were strictly maintained throughout the investigation. Temperature sensors, in particular thermocouples, play an important part in validating the predictions of solidification models. Cooling

  9. Characterization of β -Glucosidase Produced by Aspergillus niger under Solid-State Fermentation and Partially Purified Using MANAE-Agarose.

    Science.gov (United States)

    Baraldo Junior, Anderson; Borges, Diogo G; Tardioli, Paulo W; Farinas, Cristiane S

    2014-01-01

    β -Glucosidase (BGL) is a hydrolytic enzyme with specificity for a wide variety of glycoside substrates, being an enzyme with a large range of biotechnological applications. However, enzyme properties can be different depending both on the microorganism and the cultivation procedure employed. Therefore, in order to explore potential biocatalytical applications of novel enzymes, their characterization is essential. In this work, a BGL synthesized by a selected strain of Aspergillus niger cultivated under solid-state fermentation (SSF) was partially purified and fully characterized in terms of optimum pH, temperature, and thermostability. The single-step purification using MANAE-agarose in a chromatographic column yielded an enzyme solution with specific activity (17.1 IU/mg protein) adequate for the characterization procedures. Electrophoresis SDS-PAGE and size-exclusion chromatography analysis resulted in an estimated molecular mass of 60 kDa. Higher enzyme activities were found in the range between 40 and 65°C and between pH 4 and 5.5, indicating an interesting characteristic for application in the hydrolysis of lignocellulosic biomass for biofuels production. Thermostability studies of purified BGL resulted in half-lives at 37°C of 56.3 h and at 50°C of 5.4 h. These results provide support for further studies of this enzyme towards revealing its potential biotechnological applications. PMID:24940510

  10. Comparison of three methods of DNA extraction in endocervical specimens for Chlamydia trachomatis infection by spectrophotometry, agarose gel, and PCR.

    Science.gov (United States)

    Jenab, Anahita; Roghanian, Rasoul; Golbang, Naser; Golbang, Pouran; Chamani-Tabriz, Leili

    2010-06-01

    Chlamydia trachomatis is the major cause of sexually transmitted disease in the world. The aim of this study was to determine the best method of DNA extraction for detecting C. trachomatis by polymerase chain reaction (PCR) in sexually active women (n = 80) attending Shahid Beheshti Hospital in Isfahan, Iran. Endocervical swabs were collected from 80 women, 22 of whom were asymptomatic and 58 symptomatic. Three different DNA extraction methods were used in this study (phenol-chlorophorm, proteinase K, and boiling). DNA yield was evaluated by spectrophotometry, agarose gel, and PCR. The internal control was assayed by beta-globin primers (PCO4, GH20). The DNA cryptic plasmid was selected as the target for C. trachomatis and samples were examined by PCR using specific KL1 and KL2 primers. It was shown that DNA extraction by boiling was the most sensitive with the highest yield of DNA. Of the 80 samples, 17 (21.25%) showed positivity for C. trachomatis by PCR. The highest rate of C. trachomatis infection was found in the group aged between 35 and 45 years old and those who used withdrawal or an intrauterine device as methods of contraception. It was demonstrated that DNA extraction by boiling was the least expensive and a very rapid method that gave the highest DNA yield. The infection rate in the sexually active women, including symptomatic and asymptomatic, was 21.25%, with a presumably high prevalence compared with other studies done in this field.

  11. Oil Mist Compliance

    International Nuclear Information System (INIS)

    This report summarizes activities at the KCP related to evaluating and modifying machine tools in order to be in compliance with Section 23 of DOE 10 CFR 851, Worker Safety and Health Program. Section 851.23 (a) states that 'Contractors must comply with the following safety and health standards that are applicable to the hazards in their covered workplace', and subsection 9 contains the following applicable standard: 'American Congress of Governmental Industrial Hygienists (ACGIH), 'Threshold Limit Values for Chemical Substances and Physical Agents and Biological Exposure Indices,' (2005) (incorporated by reference, see (section)851.27) when the ACGIH Threshold Limit Values are lower (more protective) than permissible exposure limits in 29 CFR 1910'. In the 2005 ACGIH Threshold Limit Value book a Notice of Change was issued for exposure to mineral oil mist used in metalworking fluids (MWFs). The effects of planning for the new facility and which machine tools would be making the transition to the new facility affected which machine tools were modified

  12. Oil Mist Compliance

    Energy Technology Data Exchange (ETDEWEB)

    Lazarus, Lloyd

    2009-02-02

    This report summarizes activities at the KCP related to evaluating and modifying machine tools in order to be in compliance with Section 23 of DOE 10 CFR 851, Worker Safety and Health Program. Section 851.23 (a) states that “Contractors must comply with the following safety and health standards that are applicable to the hazards in their covered workplace”, and subsection 9 contains the following applicable standard: “American Congress of Governmental Industrial Hygienists (ACGIH), ‘Threshold Limit Values for Chemical Substances and Physical Agents and Biological Exposure Indices,’ (2005) (incorporated by reference, see §851.27) when the ACGIH Threshold Limit Values are lower (more protective) than permissible exposure limits in 29 CFR 1910.” In the 2005 ACGIH – Threshold Limit Value book a Notice of Change was issued for exposure to mineral oil mist used in metalworking fluids (MWFs). The effects of planning for the new facility and which machine tools would be making the transition to the new facility affected which machine tools were modified.

  13. Air Compliance Complaint Database (ACCD)

    Data.gov (United States)

    U.S. Environmental Protection Agency — THIS DATA ASSET NO LONGER ACTIVE: This is metadata documentation for the Region 7 Air Compliance Complaint Database (ACCD) which logs all air pollution complaints...

  14. Integrated Compliance Information System (ICIS)

    Data.gov (United States)

    U.S. Environmental Protection Agency — The purpose of ICIS is to meet evolving Enforcement and Compliance business needs for EPA and State users by integrating information into a single integrated data...

  15. A critical analysis of compliance.

    Science.gov (United States)

    Murphy, N; Canales, M

    2001-09-01

    In nursing the word compliance has competing meanings. In order to understand these meanings, nursing literature was reviewed and a critical analysis of this concept was undertaken. This included an examination of how nursing was located in relation to the historical controversy surrounding the term compliance. The philosophy that undergirds this analysis is critical theory scholarship, which focuses on language as a vehicle for social control and domination. Literature was critically analyzed according to how nurse authors define the term compliance and the historical context in which the term was used. Analysis of the literature revealed three distinct categories: evaluative, rationalization, and acceptance. Each of these categories is described and the selection criteria identified. We recommend that, nurses intent on conducting future compliance research, consider emancipatory models for their investigations. PMID:11882216

  16. Permit Compliance System (PCS) Widget

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Permit Compliance System (PCS) widget allows users to enter a specific geography and retrieve companies that have been issued permits to discharge waste water...

  17. 14 CFR 26.49 - Compliance plan.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Compliance plan. 26.49 Section 26.49... Data for Repairs and Alterations § 26.49 Compliance plan. (a) Compliance plan. Except for applicants... January 11, 2008, each person identified in §§ 26.43, 26.45, and 26.47, must submit a compliance...

  18. 10 CFR 434.604 - Compliance.

    Science.gov (United States)

    2010-01-01

    ... 10 Energy 3 2010-01-01 2010-01-01 false Compliance. 434.604 Section 434.604 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY CODE FOR NEW FEDERAL COMMERCIAL AND MULTI-FAMILY HIGH RISE RESIDENTIAL BUILDINGS Building Energy Compliance Alternative § 434.604 Compliance. 604.1 Compliance with this section...

  19. 40 CFR 63.1002 - Compliance assessment.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 10 2010-07-01 2010-07-01 false Compliance assessment. 63.1002 Section... Emission Standards for Equipment Leaks-Control Level 1 § 63.1002 Compliance assessment. (a) General procedures for compliance assessment. Compliance with this subpart will be determined by review of...

  20. Effect of cross sectional geometry on PDMS micro peristaltic pump performance: comparison of SU-8 replica molding vs. micro injection molding.

    Science.gov (United States)

    Graf, Neil J; Bowser, Michael T

    2013-10-01

    Two different fabrication methods were employed to fabricate micropumps with different cross-sectional channel geometries. The first was to fabricate rectangular cross-sectional microchannel geometries using the well known fabrication method of replica molding (REM). The second, and far less utilized fabrication technique, was to create microchannel molds using an in-house fabricated handheld micro injection molding apparatus. The injection mold apparatus was designed for use with elastomeric room temperature vulcanization (RTV) polymers, as opposed to most other injection molding machines, which are designed for use with thermoplastic polymers. The injection mold's bottom plate was used as a microchannel molding template. The molding template was created by threading a small-diameter wire (150 μm or less) through the injection mold's bottom plate, with subsequent adhesion and smoothing of a thin piece of aluminum foil over the wire-raised injection mold template. When molded against, the template produced a rounded/Gaussian-shaped PDMS microchannel. The design of the injection mold will be presented, along with a direct comparison for micropump performance metrics such as flow rate, valving characteristics, and maximum backpressures attainable for each of the respective micropump channel geometries. PMID:23917263

  1. Foaming morphology control of microcellular injection molded parts with gas counter pressure and dynamic mold temperature control

    Science.gov (United States)

    Shiu, Tai-Yi; Huang, Chao-Tsai; Chang, Rong-Yu; Hwang, Shyh-Shin

    2014-05-01

    Microcellular injection molding process is a promising solution for products with special requirements such as weight reduction, extra thin wall, high dimensional stability, clamping force reduction, etc. Despite microcellular foaming application used in reciprocating screw injection molding machine was built more than a decade, some limitations, such as poor surface quality or poor foaming control, confine the usage of this technology. Earlier CAE simulation tool for microcellular injection molding was not successful due to insufficient physical and computational considerations, limited by complicated bubble growth mechanism; so that, an economic and efficient tool for examining foaming quality of injection foaming product was lack. In this study, a recent developed three-dimensional simulation tool is used to predict injection foaming process. Predictions are carried out with commodity polypropylene and polystyrene with nitrogen and carbon dioxide supercritical fluids (SCFs). Comparisons of simulations between microcellular injection molding with and without counter pressure are discussed to provide insights into the correlation of surface quality and cell size distribution near the surface of product. Furthermore, comparisons between simulation predictions and experimental results of molding process, which is featured with dynamic mold temperature and gas counter pressure, are given for understanding quality improvement by controlling foaming morphology, and benefit of industrial application.

  2. Moldova; Taking Compliance Management Further

    OpenAIRE

    International Monetary Fund

    2012-01-01

    This report discusses implementation of the compliance risk model (CRM) by Moldova’s tax department. The CRM has shown encouraging results in 2011, in terms of extra revenue. However, the assessment reports that for long-lasting impact, the model requires further improvement in taxpayer services, audit, tax fraud investigations, information technology, and the value-added tax refund system. The compliance plan for 2012 involves implementing measures within the segment of wealthy individuals...

  3. Hazardous Waste Compliance Program Plan

    Energy Technology Data Exchange (ETDEWEB)

    Potter, G.L.; Holstein, K.A.

    1994-05-01

    The Hazardous Waste Compliance Program Plan (HWCPP) describes how the Rocky Flats Plant institutes a more effective waste management program designed to achieve and maintain strict adherence to the Resource Conservation and Recovery Act (RCRA) requirements. Emphasis is given to improve integration of line operations with programmatic and functional support activities necessary to achieve physical compliance to RCRA regulated equipment, facilities and operations at the floor level. This program focuses on specific activities occurring or which need to occur within buildings containing RCRA regulated units and activities. The plan describes a new approach to achieving and maintaining compliance. This approach concentrates authority and accountability for compliance with the line operating personnel, with support provided from the programmatic functions. This approach requires a higher degree of integration and coordination between operating and program support organizations. The principal changes in emphases are; (1) increased line operations involvement, knowledge and accountability in compliance activities, (2) improved management systems to identify, correct and/or avoid deficiencies and (3) enhanced management attention and employee awareness of compliance related matters.

  4. Analysis of Injection Molding Process Based on MoldFlow/MPI for Large Plastic Pallet%基于MoldFlow/MPI的大型塑料托盘注射成型分析

    Institute of Scientific and Technical Information of China (English)

    段贤勇

    2012-01-01

    运用MoldFlow/MPI模块对大型塑料托盘注射成型过程进行模流分析,预测了可能出现的注射短射等缺陷,根据分析结果,提出了工艺优化方案,从而缩短模具设计制造周期。%Used MoldFlow/MPI to analyze the mold flow for the large plastic pallet molding process, and predict the possible injection molding defects such as injection molding short shot. According to the analysis, it gives process optimization to reduce the mold design and manufacture cycle.

  5. 12 CFR 1710.19 - Compliance and risk management programs; compliance with other laws.

    Science.gov (United States)

    2010-01-01

    ... 12 Banks and Banking 7 2010-01-01 2010-01-01 false Compliance and risk management programs... Practices and Procedures § 1710.19 Compliance and risk management programs; compliance with other laws. (a) Compliance program. (1) An Enterprise shall establish and maintain a compliance program that is...

  6. Orientation of Carbon Fibers in Copper matrix Produced by Powder Injection Molding

    Directory of Open Access Journals (Sweden)

    Irfan Shirazi M.

    2014-07-01

    Full Text Available Fiber orientation is a big challenge in short fiber reinforced composites. Powder injection molding (PIM process has some intrinsic fiber alignment associated with it. During PIM process fibers in skin region of moldings are aligned as these regions experience higher shear flow caused by the mold walls. Fibers in the core region remain randomly aligned as these regions are far from mold walls and experience lesser shear flow. In this study short carbon fiber (CF reinforced copper matrix composite was developed by PIM process. Two copper composite feedstock formulations were prepared having 5 vol% and 10 vol% CFs and a wax based binder system. Fiber orientation was controlled during injection molding by using a modified mold that has a diverging sprue. The sprue creates converging flow when feedstock enters into the mold cavity. Fiber orientation was analysed after molding using FESEM. The orientation of fibers can be controlled by controlling flow of feedstock into the mold.

  7. Improvement of machining quality of copper-plated roll mold by controlling temperature variation

    Institute of Scientific and Technical Information of China (English)

    Tae-Jin JE; Eun-Chae JEON; Sang-Cheon PARK; Doo-Sun CHOI; Kyung-Hyun WHANG; Myung-Chang KANG

    2011-01-01

    Micro prism film used in LCD industry can be manufactured by roll to roll method with copper-plated roll mold. As copper-plated roll mold is getting larger, pitch error is getting severer. The pitch error drops the quality of micro prism film. The main cause of the pitch error was investigated during machining large roll mold whose machined length was 1 200 mm. The temperature of machining system was elevated during machining roll mold, and this elevation induced thermal expansion of the system. The temperature variation around the roll mold also made thermal expansion of the roll mold. The amount of thermal expansion had strong relationship to the amount of pitch error. Therefore, the roll mold was machined after warming-up of machining system and precise temperature controller around copper-plated roll mold was installed, which minimized the temperature variation. Finally,precise micro prism patterns without pitch error were machined on the large roll mold.

  8. Culture phases, cytotoxicity and protein expressions of agarose hydrogel induced Sp2/0, A549, MCF-7 cell line 3D cultures.

    Science.gov (United States)

    Ravi, Maddaly; Kaviya, S R; Paramesh, V

    2016-05-01

    Advancements in cell cultures are occurring at a rapid pace, an important direction is culturing cells in 3D conditions. We demonstrate the usefulness of agarose hydrogels in obtaining 3 dimensional aggregates of three cell lines, A549, MCF-7 and Sp2/0. The differences in culture phases, susceptibility to cisplatin-induced cytotoxicity are studied. Also, the 3D aggregates of the three cell lines were reverted into 2D cultures and the protein profile differences among the 2D, 3D and revert cultures were studied. The analysis of protein profile differences using UniProt data base further augment the usefulness of agarose hydrogels for obtaining 3D cell cultures.

  9. Residual stress distribution in injection molded parts

    Directory of Open Access Journals (Sweden)

    P. Postawa

    2006-08-01

    Full Text Available Purpose: The paper presents the results of the investigations of influence of the amorphous polystyrene (PSprocessing on the diversity of the internal stresses observed in the injection moulded piece.Design/methodology/approach: For the tests, the standardized mould piece designed for the investigations ofthe processing shrinkage of thermoplastics materials has been used. The samples have been prepared using theDesign of Experiment (DoE theory.The state of internal stresses has been analysed by means of photoelastic method (used stress viewer equipmenton the basis of the layout and size of the isochromatics (fields with the same colour, which determine the mouldpiece’s areas where the same value for the difference of main tensions. In the article the results of investigationsof influence of 5 chosen processing parameters such as injection temperature Tw, mould temperature Tf,clamping pressure pd, cooling time tch and the injection speed vw on the changes in isochromatics layout as adeterminant for diversity of internal stresses in injection moulded pieces have been presented.Findings: The performed investigations of the influence of injection conditions on the state of internal stressesreached for injection mould pieces were to determine the parameters of injection at which the achieved state ofthe stresses in the mould piece (described by the difference of main tensions will show the lowest values.Practical implications: Effects of examinations of influence of processing conditions on residual stress ininjection molded parts (presented in the article could find practical application in polymer industry, both smalland large enterprises.Originality/value: New approach to fast estimation of value of residual stresses were present in the paper.

  10. Heterogeneity of human alpha-fetoprotein (HAFP) as revealed by agarose gel electrophoresis and isoelectric focusing in urea-acrylamide gels

    Energy Technology Data Exchange (ETDEWEB)

    Lester, E. P.; Miller, J. B.; Yachnin, S.

    1977-01-01

    HAFP was purified from five patients with hepatoma, one with gastric cancer, and one with an embryonal cell tumor, as well as from fetal liver and a monkey tumor cell line grown in tissue culture. The pattern of microheterogeneity of purified HAFP was defined for each HAFP isolate, and was demonstrated to be present in native sera, using crossed immunoelectrophoresis in agarose gels and isoelectric focusing in polyacrylamide gels containing 8 M urea. Three, and in one case four, species were seen in agarose, and were further resolved to reveal 6 major species with isoelectric focusing which could be correlated with the agarose gel variants. We have demonstrated a relationship between the immunosuppressive potency of certain HAFP preparations and the proportion of specific HAFP isomers which they contain as shown by these techniques. We have desialylated each of our preparations and demonstrated that this does not alter immunosuppressive potency but leaves residual complex microheterogeneity. Desialylated HAFP isolates contain six major HAFP isomers by isoelectric focusing, indicating that HAFP heterogeneity is based upon multiple charge differences in the HAFP molecule, apart from sialic acid content. The nature of these charge differences remain to be determined. We postulate that these charge differences modulate the immunosuppressive potency of HAFP.

  11. Agarose film liquid phase microextraction combined with gas chromatography-mass spectrometry for the determination of polycyclic aromatic hydrocarbons in water.

    Science.gov (United States)

    Sanagi, Mohd Marsin; Loh, Saw Hong; Wan Ibrahim, Wan Aini; Hasan, Mohamed Noor

    2012-11-01

    Agarose film liquid phase microextraction (AF-LPME) procedure for the extraction and preconcentration of polycyclic aromatic hydrocarbons (PAHs) in water has been investigated. Agarose film was used for the first time as an interface between donor and acceptor phases in liquid phase microextraction which allowed for selective extraction of the analytes prior to gas chromatography-mass spectrometry. Using 1-octanol as acceptor phase, high enrichment factors in the range of 57-106 for the targeted analytes (fluorene, phenanthrene, fluoranthene and pyrene) were achieved. Under the optimum extraction conditions, the method showed good linearity in the range of 0.1-200 μgL(-1), good correlation coefficients in the range of 0.9963-0.9999, acceptable reproducibility (RSD 6.1-9.2%, n=3), low limits of detection (0.01-0.04 μgL(-1)) and satisfactory relative recoveries (92.9-104.7%). As the AF-LPME device was non-expensive, reuse or recycle of the film was not required, thus eliminating the possibility of analytes carry-over between runs. The AF-LPME technique is environment-friendly and compatible with the green chemistry concept as agarose is biodegradable polysaccharide extracted from seaweed and the procedure requires small volume of organic solvent and generates little waste. The validated method was successfully applied to the analysis of the four analytes in river water samples.

  12. Initial verification of an induction heating set-up for injection molding

    DEFF Research Database (Denmark)

    Menotti, Stefano; Hansen, Hans Nørgaard; Bissacco, Giuliano;

    2013-01-01

    Molding of thin and long parts by injection molding leads to special requirements for the mold in order to ensure proper filling and acceptable cycle time. This paper investigates the applicability of embedded induction heating for the improvement of the filling of thin long parts. The object...... selected for the investigation is a thin spiral. For the complete molding of the component, elevated mold temperatures are required. For this propose a new injection molding set-up was developed, which allows rapid heating of the cavity wall by an induction heating system. The temperature was measured by...

  13. Development of the computer-aided process planning (CAPP system for polymer injection molds manufacturing

    Directory of Open Access Journals (Sweden)

    J. Tepić

    2011-10-01

    Full Text Available Beginning of production and selling of polymer products largely depends on mold manufacturing. The costs of mold manufacturing have significant share in the final price of a product. The best way to improve and rationalize polymer injection molds production process is by doing mold design automation and manufacturing process planning automation. This paper reviews development of a dedicated process planning system for manufacturing of the mold for injection molding, which integrates computer-aided design (CAD, computer-aided process planning (CAPP and computer-aided manufacturing (CAM technologies.

  14. Relevant Aspects in Modeling of Micro-injection Molding

    Science.gov (United States)

    Nguyen-Chung, Tham; Jüttner, Gábor; Pham, Tung; Mennig, Günter

    2008-07-01

    Growing demands in the manufacturing of micro and precision components in plastics require new concepts for molding machines and micro molds on the one hand. On the other hand, a deeper understanding of the filling and solidification process in a micro mold is indispensable. In this work, the filling process of a micro spiral was analyzed by modeling the compressible flow using pressure dependent viscosity and adjusted heat transfer coefficients. At the same time, experimental filling studies were carried out on an accurately controlled micro-injection molding machine. Based on the relationship between the injection pressure and the filling degree, essential factors for the quality of the simulation can be identified. It can be shown that the flow behavior of the melt in a micro cavity of high aspect ratio is extremely dependent on the melt compressibility in the injection cylinder which needs to be considered in the simulation in order to predict an accurate flow rate. Moreover, the heat transfer coefficients between the melt and the mold wall vary significantly when changing cavity thickness and processing conditions. It is believed that a pressure dependent model for the heat transfer coefficient would be able to improve the quality of the process simulation.

  15. An investigation into the injection molding of PMR-15 polyimide

    Science.gov (United States)

    Colaluca, M. A.

    1984-01-01

    The chemorheological behavior of the PRM-15 molding compounds were characterized, the range of suitable processing parameters for injection molding in a reciprocating screw injection molding machine was determined, and the effects of the injection molding processing parameters on the mechanical properties of molded PMR-15 parts were studied. The apparatus and procedures for measuring viscosity and for determining the physical response of the material during heating are described. Results show that capillary rheometry can be effectively used with thermosets if the equipment is designed to overcome some of the inherent problems of these materials. A uniform temperature was provided in the barrel by using a circulating hot oil system. Standard capillary rheometry methods can provide the dependence of thermoset apparent viscosity on shear rate, temperature, and time. Process conditions resulting in complete imidization should be carefully defined. Specification of controlled oven temperature is inadequate and can result in incomplete imidization. For completely imidized PMR-15 heat at 15 C/min melt flow without gas evolution occurs in the temperature range of 325 C to 400 C.

  16. Mold and mycotoxin problems encountered during malting and brewing.

    Science.gov (United States)

    Wolf-Hall, Charlene E

    2007-10-20

    Fusarium infections in grains can have severe effects on malt and beer. While some degree of Fusarium mycotoxins, such as deoxynivalenol, present in infected barley may be lost during steeping, the Fusarium mold is still capable of growth and mycotoxin production during steeping, germination and kilning. Therefore, detoxification of grain before malting may not be practical unless further growth of the mold is also prevented. Methods to reduce the amount of mold growth during malting are needed. Physical, chemical and biological methods are reviewed. Irradiation looks very promising as a means to prevent Fusarium growth during malting, but the effect on the surviving mold to produce mycotoxins and the effect on malt quality needs further study. Chemical treatments such as ozonation, which would not leave residual chemical in the beer also appear to be promising. Although biological control methods may be desirable, due to the use of "natural" inhibition, the effects of these inhibitors on malt and beer quality requires further investigation. It may also be possible to incorporate detoxifying genes into fermentation yeasts, which would result in detoxification of the wort when mold growth is no longer a problem. Development of these types of technological interventions should help improve the safety of products, such as beer, made from Fusarium infected grain. PMID:17727998

  17. Disease management and medication compliance.

    Science.gov (United States)

    Cohen, Joshua; Christensen, Kathyrn; Feldman, Lanna

    2012-02-01

    Lack of medication compliance is harmful to health care systems from both a clinical and economic perspective. This study examines the methods that disease management organizations employ to identify nonadherent patients and to measure effectiveness of compliance programs for patients with diabetes, hyperlipidemia, and cystic fibrosis. In addition, this study investigates the degree to which disease managers assume risk in their contracts, and whether compliance strategies are being coordinated with payers' use of value-based insurance design, in which patient cost sharing is a function of the relative value of pharmaceuticals. This study's findings suggest that disease management may be falling short in terms of: (a) comprehensive commitment to expert-recommended at-home devices used to self-diagnose and measure health indicators; (b) early adoption of expert-recommended new technologies to measure and improve compliance; (c) intensity of use of standard tests in outpatient clinics; (d) coordination of compliance strategies with payers' use of value-based insurance design; and (e) the proportion of risk assumed in disease management contracts.

  18. 黄冶窑唐三彩制品的模具与模制成型工艺%Molds and Molding Technology for Tricolor Articles of the Tang Period Produced at the Huangye Kiln

    Institute of Scientific and Technical Information of China (English)

    刘洪淼; 廖永民

    2001-01-01

    The Dahuangye and Xiaohuangye villages in the northeast of Gongyi produced the tricolored ceramics during the Tang dynasty. These kilns had high productivity, and production was specialized. Different molds and molding methods were employed, various forms of artifats were made with different molds and molding methods. The mold froms had single and double molds; designs included plants, animals and humans; and production preeesses were regulated.

  19. Selection of thermotropic liquid crystalline polymers for rotational molding

    Science.gov (United States)

    Scribben, Eric

    Thermotropic liquid crystalline polymers (TLCPs) possess a number of physical and mechanical properties such as: excellent chemical resistance, low permeability, low coefficient of thermal expansion, high tensile strength and modulus, and good impact resistance, which make them desirable for use in the storage of cryogenic fluids. Rotational molding was selected as the processing method for these containers because it is convenient for manufacturing large storage vessels from thermoplastics. Unfortunately, there are no reports of successful TLCP rotational molding in the technical literature. The only related work reported involved the static coalescence of two TLCP powders, where three key results were reported that were expected to present problems that preclude the rotational molding process. The first result was that conventional grinding methods produced powders that were composed of high aspect ratio particles. Secondly, coalescence was observed to be either slow or incomplete and speculated that the observed difficulties with coalescence may be due to large values of the shear viscosity at low deformation rates. Finally, complete densification was not observed for the high aspect ratio particles. However, the nature of these problems were not evaluated to determine if they did, in fact, create processing difficulties for rotational molding or if it was possible to develop solutions to the problems to achieve successful rotational molding. This work is concerned with developing a resin selection method to identify viable TLCP candidates and establish processing conditions for successful rotational molding. This was accomplished by individually investigating each of the phenomenological steps of rotational molding to determine the requirements for acceptable performance in, or successful completion of, each step. The fundamental steps were: the characteristics and behavior of the powder in solids flow, the coalescence behavior of isolated particles, and the

  20. Application of Vacuum Drying to Silica Sol Ceramic Mold

    Institute of Scientific and Technical Information of China (English)

    Ming ZENG; Xinqiang YUAN; Baoluo SHEN; Yunqiu ZHENG

    2008-01-01

    Silica sol ceramic mold was made at room temperature with JN-30 silica sol, silica powder and NH4Cl. It is found that the harden time of silica sol ceramic mold is only 0.5 to 1.5 h under the amount of NH4CI solution of 7% to 8% with 15% concentration, and less surface cracks occur by using vacuum drying. The proper vacuum drying process parameters: vacuum drying temperature is 80 to 100℃, drying time is 5 h and vacuum is 0.06 to 0.07 MPa. The harden mechanics, vacuum drying mechanics and the reason of less surface cracks of silica sol ceramic mold by vacuum drying were also analyzed in this paper.

  1. Injection molding tools with micro/nano-meter pattern

    DEFF Research Database (Denmark)

    2011-01-01

    The present invention relates to methods for embedded a micrometer and/or nanometer pattern into an injection molding tool. In a first main aspect, a micro/nanometer structured imprinting device is applied in, or on, an active surface so as to transfer the micro/nanometer patterned structure to the...... tool while the imprinting device is, at least partly, within a cavity of the injection molding tool. In a second main aspect, a base plate with a micro/nanometer structured pattern positioned on an upper part is positioned on the active surface within the tool, the lower part of the base plate facing...... the tool, the active surface receiving the base plate being non-planar on a macroscopic scale. Both aspects enable a simple and effective way of transferring the pattern, and the pattern may be transferred on the active working site of tool immediately prior to molding without the need for extensive...

  2. Applications of thin carbon coatings and films in injection molding

    Science.gov (United States)

    Cabrera, Eusebio Duarte

    In this research, the technical feasibility of two novel applications of thin carbon coatings is demonstrated. The first application consists of using thin carbon coatings on molds for molding ultra-thin plastic parts (EMI) shielding for plastic parts using in mold coated nanoparticle thin films or nanopapers to create a conductive top layer. During this research, the technical feasibility of a new approach was proven which provides injection molding of ultra-thin parts at lower pressures, without the need of fast heating/fast cooling or other expensive mold modification. An in-house developed procedure by other members of our group, was employed for coating the mold surface using chemical vapor deposition (CVD) resulting in a graphene coating with carbide bonding to the mold surface. The coating resulted in a significant decrease of surface friction and consequently easiness of flow when compared to their uncoated counterparts. Thermoplastic polymers and their composites are a very attractive alternative but are hindered by the non-conductive nature of polymers. There are two general approaches used to date to achieve EMI shielding for plastic products. One is to spray a conductive metal coating onto the plastic surface forming a layer that must maintain its shielding effectiveness (SE), and its adhesion to the plastic throughout the expected life of the product. However, metal coatings add undesirable weight and tend to corrode over time. Furthermore, scratching the coating may create shielding failure; therefore, a protective topcoat may be required. The other approach is to use polymer composites filled with conductive fillers such as carbon black (CB), carbon nanofiber (CNF), and carbon nanotube (CNT). While conductive fillers may increase the electrical conductivity of polymer composites, the loading of such fillers often cannot reach a high level (EMI shielding of plastic parts was proven using in mold coated nanoparticle thin films or nanopapers to create a

  3. Long fiber polymer composite property calculation in injection molding simulation

    Science.gov (United States)

    Jin, Xiaoshi; Wang, Jin; Han, Sejin

    2013-05-01

    Long fiber filled polymer composite materials have attracted a great attention and usage in recent years. However, the injection and compression molded long fiber composite materials possess complex microstructures that include spatial variations in fiber orientation and length. This paper presents the recent implemented anisotropic rotary diffusion - reduced strain closure (ARD-RSC) model for predicting fiber orientation distribution[1] and a newly developed fiber breakage model[2] for predicting fiber length distribution in injection and compression molding simulation, and Eshelby-Mori-Tanaka model[3,4] with fiber-matrix de-bonding model[5] have been implemented to calculate the long fiber composite property distribution with predicted fiber orientation and fiber length distributions. A validation study on fiber orientation, fiber breakage and mechanical property distributions are given with injection molding process simulation.

  4. Treatment principles for the management of mold infections.

    Science.gov (United States)

    Kontoyiannis, Dimitrios P; Lewis, Russell E

    2014-11-06

    Survival rates among immunocompromised patients with invasive mold infections have markedly improved over the last decade with earlier diagnosis and new antifungal treatment options. Yet, increasing antifungal resistance, breakthrough infections with intrinsically resistant fungi, and potentially life-threatening adverse effects and drug interactions are becoming more problematic, especially with prolonged therapy. Evidence-based recommendations for treating invasive aspergillosis and mucormycosis provide excellent guidance on the initial workup and treatment of these molds, but they cannot address all of the key management issues. Herein, we discuss 10 general treatment principles in the management of invasive mold disease in immunocompromised patients and discuss how these principles can be integrated to develop an effective, individualized treatment plan.

  5. Customized mold radiotherapy with prosthetic apparatus for oral cancers

    International Nuclear Information System (INIS)

    Eight patients (6 males, 2 females; median age, 78 years; age range, 31-94 years) were treated by mold radiotherapy with a prosthetic apparatus for oral cancers between October 2006 and March 2013. The primary sites were the tongue in 3 cases, hard palate and buccal mucosa in 2 cases each, and oral floor in 1 case. The type of treatment consisted of radical radiotherapy and palliative radiotherapy in 2 cases each, and preoperative radiotherapy, postoperative radiotherapy, additional radiotherapy after external beam radiotherapy and systemic chemotherapy in 1 case each. Patients received 40-50 Gy in 8-10 fractions with mold radiotherapy. Two patients who received radical radiotherapy showed no signs of recurrence or metastasis. The present therapy contributed to patients' palliative, postoperative, and preoperative therapy. Mold radiotherapy with a prosthetic appliance was performed safely and was a useful treatment for several types of oral cancer. (author)

  6. EFFECT OF TETRACYCLINES ON THE INTRACELLULAR AMINO ACIDS OF MOLDS.

    Science.gov (United States)

    FREEMAN, B A; CIRCO, R

    1963-07-01

    Freeman, Bob A. (University of Chicago, Chicago, Ill.) and Richard Circo. Effect of tetracyclines on the intracellular amino acids of molds. J. Bacteriol. 86:38-44. 1963.-The tetracycline antibiotics were shown to alter the amino acid metabolism of molds whose growth is not markedly affected. Eight molds were grown in the presence of these antiobiotics; four exhibited a general reduction in the concentration of the intracellular amino acids, except for glutamic acid and alanine. In most of these four cultures, the tetracyclines also caused the complete disappearance of arginine, lysine, proline, phenylalanine, and tyrosine from the intracellular amino acid pool. The significance of these observations and the usefulness of the method in the study of the mechanisms of antibiotic action are discussed. PMID:14051820

  7. Decontamination formulation with additive for enhanced mold remediation

    Science.gov (United States)

    Tucker, Mark D.; Irvine, Kevin; Berger, Paul; Comstock, Robert

    2010-02-16

    Decontamination formulations with an additive for enhancing mold remediation. The formulations include a solubilizing agent (e.g., a cationic surfactant), a reactive compound (e.g., hydrogen peroxide), a carbonate or bicarbonate salt, a water-soluble bleaching activator (e.g., propylene glycol diacetate or glycerol diacetate), a mold remediation enhancer containing Fe or Mn, and water. The concentration of Fe.sup.2+ or Mn.sup.2+ ions in the aqueous mixture is in the range of about 0.0001% to about 0.001%. The enhanced formulations can be delivered, for example, as a foam, spray, liquid, fog, mist, or aerosol for neutralization of chemical compounds, and for killing certain biological compounds or agents and mold spores, on contaminated surfaces and materials.

  8. Replication of micro/nano-scale features by micro injection molding with a bulk metallic glass mold insert

    International Nuclear Information System (INIS)

    The development of MEMS and microsystems needs a reliable mass production process to fabricate micro components with micro/nano-scale features. In our study, we used the micro injection molding process to replicate micro/nano-scale channels and ridges from a bulk metallic glass (BMG) cavity insert. High-density polyethylene was used as the molding material and the design of experiment approach was adopted to systematically and statistically investigate the relationship between machine parameters, real process conditions and replication quality. The peak cavity pressure and temperature were selected as process characteristic values to describe the real process conditions that the material experienced during the filling process. The experiments revealed that the replication of ridges, including feature edge, profile and filling height, was sensitive to the flow direction; cavity pressure and temperature both increased with holding pressure and mold temperature; replication quality can be improved by increasing cavity pressure and temperature within a certain range. The replication quality of micro/nano features is tightly related to the thermomechanical history of material experienced during the molding process. In addition, the longevity and roughness of the BMG insert were also evaluated based on the number of injection molding cycles. (paper)

  9. Use of the smart tongue to monitor mold growth and discriminate between four mold species grown in liquid media

    International Nuclear Information System (INIS)

    A novel voltammetric electronic tongue, smart tongue, was employed to monitor the growth of mold and to differentiate between four types of mold grown in liquid medium. Principal component analysis (PCA) was used to extract the relevant information obtained by the smart tongue. Reference growth curves were based on measurements of dry weight and pH. The growth detected by the smart tongue was basically consistent with that observed by the measurement of dry weight and pH. The optimal combinations of electrodes and frequencies for monitoring growth were as follows: for Aspergillus, both the Pt and Au electrodes at 1 Hz, 10 Hz and 100 Hz; for Penicillium, the Pt and W electrodes at 100 Hz; for Mucor, the Pt, Pd and W electrodes at the three frequency segments; for Rhizopus, the Pd, Ti and Ag electrodes at the three frequency segments. The Ag electrode at 10 Hz or 100 Hz frequency could differentiate well between the four types of mold for culturing 6 h in the liquid media. Therefore, the smart tongue has a promising future as a modern rapid analytical technology for the real time detection of the growth of mold and for the classification model of mold.

  10. Use of the smart tongue to monitor mold growth and discriminate between four mold species grown in liquid media

    Energy Technology Data Exchange (ETDEWEB)

    Zhao Guangying, E-mail: zhaogy-user@163.com [Food Safety Key Lab of Zhejiang Province, Department of Food Quality and Safety, Zhejiang Gongshang University, Hangzhou 310035 (China); Lin Xiaona; Dou Wenchao; Tian Shiyi; Deng Shaoping; Shi Jinqin [Food Safety Key Lab of Zhejiang Province, Department of Food Quality and Safety, Zhejiang Gongshang University, Hangzhou 310035 (China)

    2011-04-01

    A novel voltammetric electronic tongue, smart tongue, was employed to monitor the growth of mold and to differentiate between four types of mold grown in liquid medium. Principal component analysis (PCA) was used to extract the relevant information obtained by the smart tongue. Reference growth curves were based on measurements of dry weight and pH. The growth detected by the smart tongue was basically consistent with that observed by the measurement of dry weight and pH. The optimal combinations of electrodes and frequencies for monitoring growth were as follows: for Aspergillus, both the Pt and Au electrodes at 1 Hz, 10 Hz and 100 Hz; for Penicillium, the Pt and W electrodes at 100 Hz; for Mucor, the Pt, Pd and W electrodes at the three frequency segments; for Rhizopus, the Pd, Ti and Ag electrodes at the three frequency segments. The Ag electrode at 10 Hz or 100 Hz frequency could differentiate well between the four types of mold for culturing 6 h in the liquid media. Therefore, the smart tongue has a promising future as a modern rapid analytical technology for the real time detection of the growth of mold and for the classification model of mold.

  11. Corporate compliance and voluntary disclosure.

    Science.gov (United States)

    Schiff, A B

    1995-09-01

    In any event, the decision to institute a corporate compliance program is a relatively simple one. In view of the ambiguity surrounding certain fraud and abuse provisions, and the corporate "death sentence" that may result from program exclusion, a compliance program is always sound corporate policy. To be sure, if the compliance program is administered improperly, it can actually increase the likelihood of whistleblower actions and create a body of potentially hurtful documentation. But these dangers can be minimized by structuring the program to protect the self-evaluative process through relevant privileges. The risks also pale in comparison to the exposure to criminal or exclusionary sanctions when improper conduct goes undetected by an organization.

  12. 240 Mold Sensitization in Chronic Rhinosinusitis Patients

    Science.gov (United States)

    Gawlik, Radoslaw; Czecior, Eugeniusz

    2012-01-01

    Background It is estimated that about 10% of the population have IgE antibodies to common inhalant molds. Exposure to fungal allergens could be linked to the presence and persistence of asthma, rhinitis and atopic dermatitis. Mold sensitization is a risk factor for development and deterioration of upper airway allergy, especially chronic rhinosinusitis. We addressed the incidence of mold allergy measured as specific IgE to molds and skin prick tests in chronic sinusitis patients. We assessed prevalence of allergic reactions to mould among surgery treated chronic sinusitis patients. Methods A group of 28 chronic sinusitis patients after surgery were included into the study. Routine medical examination, skin prick tests with common inhaled allergens and extended mold panel (Alternaria alternate, Cladosporium herbarium, Aspergilus fumigatus, Candida albicans, Mucor mucedo, Botrytis cinerea, Rhisopus nigricans, Penicilliumi notatum, Fusarum moniliforme Pullularia pullulans (Allergopharma, Germany), tIgE, asIgE measurement were performed (Phadia, Sweden). All investigated patients were consulted by laryngologist and mycological examination was performed. Results We found that sensitization to at least one allergen was present in 43.8(14/32) of sinusitis patients. The most prevalent was sensitization to house dust mite Dermatophagoides pt., found in 21.8 % (7/32) patients. Positive results of skin prick tests with Candida albicans we observed in 18.8% (6/32), with Alternaria alternate in 15,6% (5/32), Cladosporium herbarium in 6,3% (2/32), Aspergilus fumigatus in 3,13 % (1/32). None of investigated patients presented sensitization to other mold allergens. Microbiological methods demonstrated fungal infection only in 2 patients. Conclusions Almost half of chronic sinusitis patients presented sensitization to at least one allergen. Fungal allergy is relatively rare in chronic sinusitis patients.

  13. CT use for nasopharingeal molds realization in endocavitary brachytherapy

    International Nuclear Information System (INIS)

    Purpose: We present the following procedure for the making of individual molds with dental silicone for endocavitary brachytherapy of nasopharingeal cancer aided by CT scan. Procedure: Head immobilization during the realization of nasopharynx CT. Planification of treatment using these CT images, to determine the optimum position of radioactive sources. Printing on paper CT images with the nasopharynx contoured walls and the radioactive sources position. Realization of the mold in plastiline with the aid of the cuts of printer paper cut out with the nasopharynx form. Obtaining of the negative of the mold of plastiline by means of the use of alginate. Placement of two number 20 rectal rigid catheters with metal malleable bars inside them, in order to give them an adequate form in relation to the previous carried out planning. Filling in of alginato negative, where rectal catheters were placed, with Provil MCD Bayer Dental, a silicone based material for precision impression. We recommend to crossing the catheters' end with a number 2 silk thread to secure the catheter. An end of the silk thread is left outside the mold in order to help the extraction at the end of application. We advise to carry out a neuroleptic anaesthesia for its insertion, for the purpose of achieving a soft palate suitable relaxation. It makes the insertion easier. Repeat CT with the mold and phantoms in position to know a definitive dose distribution calculation. Conclusion: This method avoids the necessity of general anaesthesia in the realization of individual molds of nasopharyx for endocavitary brachytherapy and it improves the implant dosimetry

  14. FIBER ORIENTATION IN INJECTION MOLDED LONG CARBON FIBER THERMOPLASTIC COMPOSITES

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Jin; Nguyen, Ba Nghiep; Mathur, Raj N.; Sharma, Bhisham; Sangid, Michael D.; Costa, Franco; Jin, Xiaoshi; Tucker III, Charles L.; Fifield, Leonard S.

    2015-03-23

    A set of edge-gated and center-gated plaques were injection molded with long carbon fiber-reinforced thermoplastic composites, and the fiber orientation was measured at different locations of the plaques. Autodesk Simulation Moldflow Insight (ASMI) software was used to simulate the injection molding of these plaques and to predict the fiber orientation, using the anisotropic rotary diffusion and the reduced strain closure models. The phenomenological parameters of the orientation models were carefully identified by fitting to the measured orientation data. The fiber orientation predictions show very good agreement with the experimental data.

  15. Packing parameters effect on injection molding of polypropylene nanostructured surfaces

    DEFF Research Database (Denmark)

    Calaon, Matteo; Tosello, Guido; Hansen, Hans Nørgaard;

    2012-01-01

    In today´s industry, applications involving surface patterning of sub-μm to nanometer scale structures have shown a high growth potential. To investigate the injection molding capability of replicating sub-μm surface texture on a large scale area, a 30x80 mm2 tool insert with surface structures...... having a diameter of 500 nm was employed. The tool insert surface was produced using chemical-based-batch techniques such aluminum anodization and nickel electroplating. During the injection molding process, polypropylene (PP) was employed as material and packing phase parameters (packing time, packing...

  16. Evaluation of Methods to Control Mold on Hardwood Pallets

    OpenAIRE

    Blount, Thomas Richard

    2013-01-01

    The objectives of this project were:1.����To compare the drying cost and drying time for oak and poplar pallets for the following mold mitigation strategies for hardwood pallets: air drying, forced air drying (fan shed), kiln drying to 25% moisture content and chemical treatment, and2.����Develop and evaluate a procedure for preventing and controlling mold growth on heat treated hardwood palletsTwenty red oak pallets and twenty yellow-poplar pallets were tested for each drying...

  17. Study on Antigravity Mold Filling by Conservative Scalar Method

    Institute of Scientific and Technical Information of China (English)

    李日; 王友序; 杨根仓; 毛协民

    2003-01-01

    By SIMPLE method and Van-Leer scheme, a program on numerical simulation for 3D mold filling has been developed. The fluid flow field of gas and liquid is calculated in couples by a single phase N-S equation using SIMPLE method, and free surface control equation is handied by Van-Leer scheme. Then it is verified by an anti-gravity mold filling of thin wall plate. In order to demonstrate its ability to simulate 3D casting, an anti-gravity mould filling of a cube is computed by the program.

  18. Biological Control of Olive Green Mold in Agaricus bisporus Cultivation.

    Science.gov (United States)

    Tautorus, T E; Townsley, P M

    1983-02-01

    Successful methods to control the damaging weed mold Chaetomium olivaceum (olive green mold) in mushroom beds are not presently known. An attempt was made to control C. olivaceum by biological means. A thermophilic Bacillus sp. which showed dramatic activity against C. olivaceum on Trypticase soy agar (BBL Microbiology Systems)-0.4% yeast extract agar plates was isolated from commercial mushroom compost (phase I). When inoculated into conventional and hydroponic mushroom beds, the bacillus not only provided a significant degree of protection from C. olivaceum, but also increased yields of Agaricus bisporus.

  19. Tax Compliance Inventory: TAX-I Voluntary tax compliance, enforced tax compliance, tax avoidance, and tax evasion.

    Science.gov (United States)

    Kirchler, Erich; Wahl, Ingrid

    2010-06-01

    Surveys on tax compliance and non-compliance often rely on ad hoc formulated items which lack standardization and empirical validation. We present an inventory to assess tax compliance and distinguish between different forms of compliance and non-compliance: voluntary versus enforced compliance, tax avoidance, and tax evasion. First, items to measure voluntary and enforced compliance, avoidance, and evasion were drawn up (collected from past research and newly developed), and tested empirically with the aim of producing four validated scales with a clear factorial structure. Second, findings from the first analyses were replicated and extended to validation on the basis of motivational postures. A standardized inventory is provided which can be used in surveys in order to collect data which are comparable across research focusing on self-reports. The inventory can be used in either of two ways: either in its entirety, or by applying the single scales independently, allowing an economical and fast assessment of different facets of tax compliance.

  20. Application of statistical methods for analyzing the relationship between casting distortion, mold filling, and interfacial heat transfer in sand molds

    Energy Technology Data Exchange (ETDEWEB)

    Y. A. Owusu

    1999-03-31

    This report presents a statistical method of evaluating geometric tolerances of casting products using point cloud data generated by coordinate measuring machine (CMM) process. The focus of this report is to present a statistical-based approach to evaluate the differences in dimensional and form variations or tolerances of casting products as affected by casting gating system, molding material, casting thickness, and casting orientation at the mold-metal interface. Form parameters such as flatness, parallelism, and other geometric profiles such as angularity, casting length, and height of casting products were obtained and analyzed from CMM point cloud data. In order to relate the dimensional and form errors to the factors under consideration such as flatness and parallelism, a factorial analysis of variance and statistical test means methods were performed to identify the factors that contributed to the casting distortion at the mold-metal interface.

  1. Injection molding of thermoplastic elastomers for microstructured substrates

    Science.gov (United States)

    Birkar, Smita

    Amorphous and semi-crystalline thermoplastic polymers have been widely investigated for injection molding of parts with microstructured surfaces. Microstructured surfaces injection molded from thermoplastic elastomers have emerging applications as superhydrobic surfaces and patterned adhesives, but there is a limited understanding of the factors affecting replication with these materials. This research was a continued investigation of block copolymer thermoplastic elastomers as well as the first in-depth examination of thermoplastic vulcanizates for injection molding microfeatures. The first focus of this research was the interactions between tooling aspect ratio and feature orientation (negative and positive tooling) and thermoplastic elastomer hard segment content on microfeature replication. Electroformed nickel tooling having positive and negative features with different geometries and aspect ratios of 0.02:1 to 2:1 were molded from three copolyester thermoplastic elastomers with similar chemistry and different hardness values. The tooling and part features were characterized for feature depth and height as well as feature definition using scanning electron microscopy and optical profilometry. Results were correlated with elastomer properties. In the second parts of this research, the effects of microfeature spacing on the replication of thermoplastic elastomer features was investigated using micropillars with two diameters (10 and 20 mum) and three spacing ratios (0.5:1, 1:1, and 2:1). The tooling and part features were characterized for feature depth and height as well as feature definition using scanning electron microscopy and optical profilometry. Feature spacing significantly affected the replication of micropillars using a thermoplastic elastomer. This replication was competition between cooling and pressurization of the melt. Wider spacing between smaller features allowed cooling in the tooling lands to dominate the feature filling. Higher pressures did

  2. The effect of mold materials on the overlay accuracy of a roll-to-roll imprinting system using UV LED illumination within a transparent mold

    Science.gov (United States)

    Choi, Sungwoo; Kook, YunHo; Kim, ChulHo; Yoo, SoonSung; Park, Kwon-Shik; Kim, Seok-min; Kang, Shinill

    2016-06-01

    Although several studies on the roll-to-roll (R2R) imprinting process have reported achieving flexible electronics, improving the alignment accuracy in the overlay process of R2R imprinting is recognized as the biggest problem for the commercialization of this technology. For an overlay technique with high alignment accuracy, it is essential to develop a roll mold with high positional accuracy. In this study, a method for fabricating a roll mold with high positional accuracy is proposed by wrapping a thin glass substrate flexible mold around the transparent roll base, because it can provide higher mechanical strength and thermal stability than a conventional polymer substrate. To confirm the usability of the proposed process, the prepared roll mold was used to fabricate a test pattern of thin-film transistor backplane for a rollable display. The positional and overlay accuracy of the roll mold with the proposed thin glass substrate flexible mold were compared with the roll mold with a conventional polymer substrate flexible mold. Large-area transparent flexible molds with a size of 470  ×  370 mm were fabricated by an ultraviolet (UV) imprinting process on thin glass and polyethylene terephthalate substrates, and these flexible molds were wrapped around a roll base of 125 mm radius through a precision alignment process. After an anti-adhesion treatment and the wrapping process, the roll mold with the polymer substrate showed a ~180 μm positional error, whereas the thin glass substrate showed a ~30 μm positional error. After the overlay process using the R2R imprinting system with the alignment system, an average overlay error of ~3 μm was obtained when the thin glass flexible wrapped roll mold was used, whereas a ~22 μm overlay error was obtained when the polymer substrate flexible wrapped roll mold was used.

  3. Computer precision simulation for titanium casting centrifugal mold filling of prescision titanium castings

    OpenAIRE

    Xu, Daming; LI, XIN; Geving AN

    2004-01-01

    Computer simulation codes were developed based on proposed mathematical model for centrifugal mold filling processes and previous computer software for 3D mold filling and solidification of castings. Sample simulations were implemented for mold filling processes of precision titanium castings under gravity and different centrifugal casting techniques. The computation results show that the alloy melt has a much stronger mold filling ability for thin section castings unde a centrifugal force fi...

  4. Injection molding of iPP samples in controlled conditions and resulting morphology

    Science.gov (United States)

    Sessa, Nino; De Santis, Felice; Pantani, Roberto

    2015-12-01

    Injection molded parts are driven down in size and weight especially for electronic applications. In this work, an investigation was carried out on the process of injection molding of thin iPP samples and on the morphology of these parts. Melt flow in the mold cavity was analyzed and described with a mathematical model. Influence of mold temperature and injection pressure was analyzed. Samples orientation was studied using optical microscopy.

  5. Injection molding of iPP samples in controlled conditions and resulting morphology

    Energy Technology Data Exchange (ETDEWEB)

    Sessa, Nino, E-mail: ninosessa.ns@gmail.com; De Santis, Felice, E-mail: fedesantis@unisa.it; Pantani, Roberto, E-mail: rpantani@unisa.it [Department of Industrial Engineering, University of Salerno, 84084 Fisciano (Italy)

    2015-12-17

    Injection molded parts are driven down in size and weight especially for electronic applications. In this work, an investigation was carried out on the process of injection molding of thin iPP samples and on the morphology of these parts. Melt flow in the mold cavity was analyzed and described with a mathematical model. Influence of mold temperature and injection pressure was analyzed. Samples orientation was studied using optical microscopy.

  6. Validation of precision powder injection molding process simulations using a spiral test geometry

    OpenAIRE

    Marhöfer, Maximilian; Müller, Tobias; TOSELLO, Guido; Islam, Aminul; Hansen, Hans N.; Piotter, Volker

    2015-01-01

    Like in many other areas of engineering, process simulations find application in precision injection molding to assist and optimize the quality and design of precise products and the molding process. Injection molding comprises mainly the manufacturing of plastic components. However, the variant of precision powder injection molding for the production of metallic and ceramic micro parts raises more and more interest though. Consequently, in the entire field the demand for simulation tools inc...

  7. Study on Improving Thickness Uniformity of Microfluidic Chip Mold in the Electroforming Process

    OpenAIRE

    Liqun Du; Tong Yang; Ming Zhao; Yousheng Tao; Lei Luo; Lei Wang; Chong Liu

    2016-01-01

    Electroformed microfluidic chip mold faces the problem of uneven thickness, which decreases the dimensional accuracy of the mold, and increases the production cost. To fabricate a mold with uniform thickness, two methods are investigated. Firstly, experiments are carried out to study how the ultrasonic agitation affects the thickness uniformity of the mold. It is found that the thickness uniformity is maximally improved by about 30% after 2 h electroforming under 200 kHz and 500 W ultrasonic ...

  8. Quantifying mold biomass on gypsum board: Comparison of ergosterol and beta-N-acetylhexosaminidase as mold biomass parameters

    DEFF Research Database (Denmark)

    Reeslev, M.; Miller, M.; Nielsen, Kristian Fog

    2003-01-01

    monitored from inoculation to stationary phase. Regression analysis showed a good linear correlation to biomass density for both ergosterol content and beta-N-acetylhexosaminidase activity. The same two mold species were inoculated onto wallpapered gypsum board, from which a direct biomass measurement...... density from ergosterol content and beta-N-acetylhexosaminidase activity were determined. The CFs were used to estimate the biomass density of the molds grown on gypsum board. The biomass densities estimated from ergosterol content and beta-N-acetylhexosaminidase activity data gave similar results......, showing significantly slower growth and lower stationary-phase biomass density on gypsum board than on agar....

  9. Mold Species in Dust from the International Space Station Identified and Quantified by Mold Specific Quantitative PCR

    Science.gov (United States)

    Vesper, Stephen J.; Wong, Wing; Kuo, C. Mike; Pierson, Duane L.

    2008-01-01

    Dust was collected over a period of several weeks in 2007 from various HEPA filters in the U.S. Laboratory Module of the International Space Station (ISS). The dust was returned on the Space Shuttle Atlantis, mixed, sieved, and the DNA was extracted. Using a DNA-based method called mold specific quantitative PCR (MSQPCR), 39 molds were measured in the dust. Opportunistic pathogens Aspergillus flavus and A. niger and toxin producers Penicillium chrysogenum and P. brevicompactum were found at relatively high concentrations (compared to U.S. homes). No cells of the opportunistic pathogens A. fumigatus, A. terreus, Fusarium solani or Candida albicans were detected.

  10. MoldFlow软件在梳子注射模结构改进及其成型缺陷分析中的应用%The Application of MoldFlow Software in the Structure Improvement and Analysis of forming Defects of Comb Injection Molding

    Institute of Scientific and Technical Information of China (English)

    陈叶娣

    2012-01-01

    MoldFlow software is applied to improve the mold structure and solve molding defects according to the problems of comb injection molding during trying mold. These will be provided some valuable references. Aunusual power is provided for the wide application of MoldFlow software in the design of injection mold.%根据梳子注射模在试模过程中存在的一些问题,采用MoldFlow软件进行分析,为改进模具结构、解决其成型缺陷提供有价值的参考。

  11. 300 area TEDF permit compliance monitoring plan

    Energy Technology Data Exchange (ETDEWEB)

    BERNESKI, L.D.

    1998-11-20

    This document presents the permit compliance monitoring plan for the 300 Area Treated Effluent Disposal Facility (TEDF). It addresses the compliance with the National Pollutant Discharge Elimination System (NPDES) permit and Department of Natural Resources Aquatic Lands Sewer Outfall Lease.

  12. Client Compliance with Homework Directives during Counseling.

    Science.gov (United States)

    Worthington, Everett L., Jr.

    1986-01-01

    Investigated compliance as a function of counselor, client, and therapy variables. Results indicated that variables associated with the conduct of counseling more strongly influenced compliance with homework than did either counselor or client variables. (Author/BL)

  13. Clean Air Markets - Compliance Query Wizard

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Compliance Query Wizard is part of a suite of Clean Air Markets-related tools that are accessible at http://ampd.epa.gov/ampd/. The Compliance module provides...

  14. Mobile Source Emissions Regulatory Compliance Data Inventory

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Mobile Source Emissions Regulatory Compliance Data Inventory data asset contains measured summary compliance information on light-duty, heavy-duty, and non-road...

  15. Enforcement and Compliance History Online (ECHO) Widget

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Enforcement and Compliance History Online (ECHO) widget displays the compliance records of larger facilities within a user-specified area of interest as...

  16. Mobile Source Emissions Regulatory Compliance Data

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Engine and Vehicle Compliance Certification and Fuel Economy Inventory contains measured emissions and fuel economy compliance information for all types of...

  17. Three-dimensional numerical modeling of an induction heated injection molding tool with flow visualization

    DEFF Research Database (Denmark)

    Guerrier, Patrick; Tosello, Guido; Nielsen, Kaspar Kirstein;

    2016-01-01

    Using elevated mold temperature is known to have a positive influence of final injection molded parts. Induction heating is a method that allow obtaining a rapid thermal cycle, so the overall molding cycle time is not increased. In the present research work, an integrated multi-turn induction hea...

  18. Injection molding of nanopatterned surfaces in the sub-micrometer range with induction heating aid

    DEFF Research Database (Denmark)

    Menotti, Stefano; Hansen, Hans Nørgaard; Bissacco, Giuliano;

    2014-01-01

    Replication of sub-micrometer structures by injection molding leads to special requirements for the mold in order to ensure proper replica and acceptable cycle time. This paper investigates the applicability of induction heating embedded into the mold for the improvement of nanopattern replicatio...

  19. Temperature Dependence and Magnetic Properties of Injection Molding Tool Materials Used in Induction Heating

    DEFF Research Database (Denmark)

    Guerrier, Patrick; Nielsen, Kaspar Kirstein; Hattel, Jesper Henri

    2015-01-01

    To analyze the heating phase of an induction heated injection molding tool precisely, the temperature-dependent magnetic properties, B–H curves, and the hysteresis loss are necessary for the molding tool materials. Hence, injection molding tool steels, core materials among other materials have, i...... flux density, and hysteresis loss versus magnetic flux density have been extracted and are presented....

  20. The history of molded fiber packaging: a 20th century pulp story

    NARCIS (Netherlands)

    Wever, R.; Twede, D.

    2007-01-01

    Molded fiber packaging, which is also referred to as molded pulp packaging, has been around for a little over a hundred years now. From the first patent, dating from 1903, until approximately 25 years ago molded fiber packaging was a niche product used mainly for packing eggs. However, in the last t

  1. 75 FR 55340 - Recovery Fact Sheet 9580.100, Mold Remediation

    Science.gov (United States)

    2010-09-10

    ... SECURITY Federal Emergency Management Agency Recovery Fact Sheet 9580.100, Mold Remediation AGENCY: Federal... Emergency Management Agency (FEMA) is accepting comments on Recovery Fact Sheet RP9580.100, Mold Remediation... The Recovery Fact Sheet RP9580.100, Mold Remediation, identifies the expenses related to...

  2. Design of Injection Mold for Connector Based on MoldFlow Software%基于MoldFlow的接插件注射模设计

    Institute of Scientific and Technical Information of China (English)

    孙立新

    2010-01-01

    通过对接插件的结构和工艺的分析,合理确定了模具抽芯机构的结构,同时应用模流分析软件MoldFlow确定了模具的最佳浇口位置,并对塑件的质量进行了预测.

  3. Corporate compliance: implications for trustees.

    Science.gov (United States)

    Commins, K

    1998-01-01

    In this era of fraud and abuse enforcement efforts, hospital trustees are facing potential liability in the event that an investigation reveals the hospital has violated state or federal provisions pertaining to fraud and abuse. This liability can be minimized, or avoided, by ensuring that an effective compliance plan is in place prior to such an investigation.

  4. Join the Copyright Compliance Team

    Science.gov (United States)

    Butler, Rebecca P.

    2008-01-01

    School librarians are often the only educators in the school with copyright training and, by default, are perceived of as the copyright experts. Likewise, the buck stops with the head administrator; ultimately that person is accountable for the school's compliance with policies and laws, including copyright laws and fair use. Along with this, more…

  5. Project Compliance with Enterprise Architecture

    NARCIS (Netherlands)

    Foorthuis, R.M.

    2012-01-01

    This research project set out to identify effective practices and models for working with projects that are required to comply with Enterprise Architecture (EA), and investigate the benefits and drawbacks brought about by compliance. Research methods used are canonical action research, a statistical

  6. ETHICS AND COMPLIANCE IN BUSINESS

    Directory of Open Access Journals (Sweden)

    ANDREESCU Nicoleta Alina

    2015-05-01

    Full Text Available In this paper, we have studied the evolution of the business ethics concept through the prism of definitions from some renowned authors in the field and through the approach model of the business ethics and by implementing it in the company level. We have found out that in the last 40 years this concept has evolved from a theoretical aspect, as well as a practical one. Companies are motivated to implement ethics and compliance programs in business so that they can manage the changes that come from society. If, until recently, all that mattered for a company was profit, in the last decades, the situation changed. In order to develop a durable business, it is essential to have a good reputation. Owning and implementing an ethics and compliance program in business has become an imperative for companies, regardless of their activity sector. The role of the compliance department becomes more pregnant in each company: the employees need safety, the existence of communication lines provides comfort. From the partners in business’ point of view, owning such a program is a necessity, a condition, and not conforming to the principles of business ethics can lead to the isolation of the company. The ethics and compliance programs in business are instruments that protect the company by implementing certain proactive identification mechanisms that ensure the development of an ethical organizational culture.

  7. Audit-based compliance control

    NARCIS (Netherlands)

    Cederquist, J.G.; Corin, R.J.; Dekker, M.A.C.; Etalle, S.; Hartog, den J.I.; Lenzini, G.; Dimitrakos, T.; Martinelli, F.; Ryan, P.Y.A.; Schneider, S.

    2007-01-01

    In this paper we introduce a new framework for controlling compliance to discretionary access control policies [Cederquist et al. in Proceedings of the International Workshop on Policies for Distributed Systems and Networks (POLICY), 2005; Corin et al. in Proceedings of the IFIP Workshop on Formal A

  8. A Review of Factors for Tax Compliance

    OpenAIRE

    Nicoleta BARBUTA-MISU

    2011-01-01

    The aim of this paper is to identify the variables of tax compliance analysed by researchers from various countries and adapting them to the Romanian conditions to create a model to include factors that influence decision of tax compliance. Tax compliance has been studied in economics by analysing the individual decision of a representative person between paying taxes and evading taxes. In the research of tax compliance have been done many empirical studies that emphasized the impact of a wid...

  9. Developing a nursing corporate compliance program.

    Science.gov (United States)

    Bartis, Janice A; Sullivan, Trent

    2002-09-01

    This article presents the process that a large urban tertiary care hospital engaged in when developing a corporate compliance program for nursing. The purpose of this article is to demonstrate how nurse executives can successfully implement a comprehensive and practical nursing corporate compliance program. This article describes in detail the 5 steps the hospital took to develop its nursing corporate compliance program and provides examples of tools to guide you in developing a nursing corporate compliance program.

  10. 24 CFR 108.21 - Civil rights/compliance reviewing office compliance responsibility.

    Science.gov (United States)

    2010-04-01

    ... 24 Housing and Urban Development 1 2010-04-01 2010-04-01 false Civil rights/compliance reviewing... MARKETING § 108.21 Civil rights/compliance reviewing office compliance responsibility. The civil rights/compliance reviewing office shall be responsible for determining whether an applicant's actions are...

  11. QTLs for Snow Mold Disease Resistance in Creeping Bentgrass

    Science.gov (United States)

    Snow molds caused by Typhula spp. are the most economically important winter diseases of turfgrass in the northern and alpine regions of the United States and Canada. During winter, the psychrophilic pathogens take advantage of the weakened host plants at low temperatures under persistent snow cover...

  12. PHYSICAL PROPERTIES OF EXTRUDED AND INJECTION MOLDED CORN GLUTEN MEAL

    Science.gov (United States)

    This study was performed to investigate the compounding of corn gluten meal (CGM) and decanoic acid and to evaluate their mechanical properties. The mixture of CGM and 30% decanoic acid was compounded in a twin screw extruder, followed by injection molding. Scanning electron microscopy (SEM), tens...

  13. Metal Injection Molding of Alloy 718 for Aerospace Applications

    Science.gov (United States)

    Ott, Eric A.; Peretti, Michael W.

    2012-02-01

    The metal injection molding process, used in the automotive, medical, and consumer markets for several decades, was investigated for application to superalloys for small, complex-shaped, aerospace components. With sufficient control on processing, inclusion risks, and chemistry, the process can successfully be applied to superalloy 718 components. Assessments included tensile and fatigue property evaluation, characterization of microstructure, and development of an AMS specification.

  14. Fiber-Based, Injection-Molded Optofluidic Systems

    DEFF Research Database (Denmark)

    Matteucci, Marco; Triches, Marco; Nava, Giovanni;

    2015-01-01

    We present a method to fabricate polymer optofluidic systems by means of injection molding that allow the insertion of standard optical fibers. The chip fabrication and assembly methods produce large numbers of robust optofluidic systems that can be easily assembled and disposed of, yet allow pre...

  15. Optimizing biomass blends for manufacturing molded packaging materials using mycelium

    Science.gov (United States)

    Polystyrene is one of the most widely used plastics and is commonly produced in three forms: 1) Extruded polystyrene – disposable utensils, CD/DVD cases, yogurt containers, smoke alarm housing, etc.; 2) Expanded polystyrene foam – molded packaging materials and packaging "peanuts"; 3) Extruded polys...

  16. Smart plastic functionalization by nanoimprint and injection molding

    DEFF Research Database (Denmark)

    Zalkovskij, Maksim; Thamdrup, Lasse Højlund; Smistrup, Kristian;

    2015-01-01

    In this paper, we present a route for making smart functionalized plastic parts by injection molding with sub-micrometer surface structures. The method is based on combining planar processes well known and established within silicon micro and sub-micro fabrication with proven high resolution...

  17. Seating tool for preparing molded-plug terminations on FCC

    Science.gov (United States)

    Chambers, C. M.; Corum, C. C.

    1971-01-01

    Hand-operated tool positions and seats window piece and conductor spacer onto conductors of two stripped cables during process of terminating cables with molded plug. Tool accommodates cables up to 3 in. wide and is used in conjunction with folding tools.

  18. Ion channel recordings on an injection-molded polymer chip

    DEFF Research Database (Denmark)

    Tanzi, Simone; Matteucci, Marco; Christiansen, Thomas Lehrmann;

    2013-01-01

    In this paper, we demonstrate recordings of the ion channel activity across the cell membrane in a biological cell by employing the so-called patch clamping technique on an injection-molded polymer microfluidic device. The findings will allow direct recordings of ion channel activity to be made u...

  19. A Recurrent Neural Network for Warpage Prediction in Injection Molding

    Directory of Open Access Journals (Sweden)

    A. Alvarado-Iniesta

    2012-11-01

    Full Text Available Injection molding is classified as one of the most flexible and economical manufacturing processes with high volumeof plastic molded parts. Causes of variations in the process are related to the vast number of factors acting during aregular production run, which directly impacts the quality of final products. A common quality trouble in finishedproducts is the presence of warpage. Thus, this study aimed to design a system based on recurrent neural networksto predict warpage defects in products manufactured through injection molding. Five process parameters areemployed for being considered to be critical and have a great impact on the warpage of plastic components. Thisstudy used the finite element analysis software Moldflow to simulate the injection molding process to collect data inorder to train and test the recurrent neural network. Recurrent neural networks were used to understand the dynamicsof the process and due to their memorization ability, warpage values might be predicted accurately. Results show thedesigned network works well in prediction tasks, overcoming those predictions generated by feedforward neuralnetworks.

  20. The Role of Molding Compound Microstructure for Packaging Reliability

    NARCIS (Netherlands)

    Fischer, H.R.; Nabi, H.S.; Weiss, L.; Gielen, A.W.J.

    2015-01-01

    Molding compounds are key materials to deliver well packaged reliable IC’s for demanding applications, such as automotive electronics. With shrinking sizes of IC’s and the increased requirements with respect to loading conditions, application environment and lifetime, the reliability of the packagin

  1. Evaluation of stability for monolayer injection molding tools coating

    DEFF Research Database (Denmark)

    Cech, Jiri; Taboryski, Rafael J.

    2012-01-01

    . Detectable coating presence was indicated by an increased angle on all post IM samples. To conclude, we present mold coating evaluation method, which is well suited for ultrathin, controlable, covalently bonded coating, that is reasonably durable, affordable, scalable to production, detectable on surface...

  2. Corporate compliance: framework and implementation.

    Science.gov (United States)

    Fowler, N

    1999-01-01

    The federal government has created numerous programs to combat fraud and abuse. The government now encourages healthcare facilities to have a corporate compliance program (CCP), a plan that reduces the chances that the facility will violate laws or regulations. A CCP is an organization-wide program comprised of a code of conduct and written policies, internal monitoring and auditing standards, employee training, feedback mechanisms and other features, all designed to prevent and detect violations of governmental laws, regulations and policies. It is a system or method ensuring that employees understand and will comply with laws that apply to what they do every day. Seven factors, based on federal sentencing guidelines, provide the framework for developing a CCP. First, a facility must establish rules that are reasonably capable of reducing criminal conduct. Second, high-level personnel must oversee the compliance effort. Third, a facility must use due care in delegating authority in the compliance initiative. Fourth, standards must be communicated effectively to employees, and fifth, a facility must take reasonable steps to achieve compliance. Sixth, standards must be enforced consistently across the organization and last, standards must be modified or changed for reported concerns, to ensure they are not repeated. PROMINA Health System, Inc. in Atlanta, Ga., designed a program to meet federal guidelines. It started with a self-assessment to define its areas or risk. Next, it created the internal structure and assigned organizational responsibility for running the CCP. PROMINA then developed standards of business and professional conduct, established vehicles of communication and trained employees on the standards. Finally, it continues to develop evidence of the program's effectiveness by monitoring and documenting its compliance activities.

  3. 38 CFR 18.6 - Compliance information.

    Science.gov (United States)

    2010-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 2 2010-07-01 2010-07-01 false Compliance information... THE CIVIL RIGHTS ACT OF 1964 General § 18.6 Compliance information. (a) Cooperation and assistance... compliance reports at such times, and in such form and containing such information, as the responsible...

  4. 40 CFR 68.58 - Compliance audits.

    Science.gov (United States)

    2010-07-01

    ... are being followed. (b) The compliance audit shall be conducted by at least one person knowledgeable... the compliance audit and document that deficiencies have been corrected. (e) The owner or operator shall retain the two (2) most recent compliance audit reports. This requirement does not apply to...

  5. 10 CFR 434.509 - Compliance.

    Science.gov (United States)

    2010-01-01

    ... 10 Energy 3 2010-01-01 2010-01-01 false Compliance. 434.509 Section 434.509 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY CODE FOR NEW FEDERAL COMMERCIAL AND MULTI-FAMILY HIGH RISE RESIDENTIAL BUILDINGS Building Energy Cost Compliance Alternative § 434.509 Compliance. 509.1If the Design Energy...

  6. How Physical Design Can Influence Copyright Compliance

    Science.gov (United States)

    Harper, Meghan

    2007-01-01

    Most school librarians do not think of copyright compliance and facilities planning in the same breath. Yet the design of space--physical and virtual--can discourage or promote compliance, or even help police it. Placement of and access to equipment, traffic patterns, signage, and student workspace all may influence copyright-compliance behavior…

  7. 42 CFR 124.503 - Compliance level.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Compliance level. 124.503 Section 124.503 Public... Unable To Pay § 124.503 Compliance level. (a) Annual compliance level. Subject to the provisions of this... persons unable to pay if it provides for the fiscal year uncompensated services at a level not less...

  8. 22 CFR 209.6 - Compliance information.

    Science.gov (United States)

    2010-04-01

    ... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Compliance information. 209.6 Section 209.6... § 209.6 Compliance information. (a) Cooperation and assistance. The Administrator shall to the fullest... and accurate compliance reports at such times, and in such form and containing such information,...

  9. 40 CFR 425.05 - Compliance dates.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 29 2010-07-01 2010-07-01 false Compliance dates. 425.05 Section 425.05 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS LEATHER TANNING AND FINISHING POINT SOURCE CATEGORY General Provisions § 425.05 Compliance dates. The compliance date for new source...

  10. Incipient flocculation molding: A new ceramic-forming technique

    Science.gov (United States)

    Arrasmith, Steven Reade

    Incipient Flocculation Molding (IFM) was conceived as a new near-net-shape forming technique for ceramic components. It was hypothesized that the development of a temperature-dependent deflocculant would result in a forming technique that is flexible, efficient, and capable of producing a superior microstructure with improved mechanical properties from highly reactive, submicron ceramic powders. IFM utilizes a concentrated, nonaqueous, sterically stabilized ceramic powder and/or colloidal suspension which is injected into a non-porous mold. The suspension is then flocculated by destabilizing the suspension by lowering the temperature. Flocculation is both rapid and reversible. Cooling to -20°C produces a green body with sufficient strength for removal from the mold. The solvent is removed from the green body by evaporation. The dried green body is subsequently sintered to form a dense ceramic monolith. This is the first ceramic forming method based upon the manipulation of a sterically-stabilized suspension. To demonstrate IFM, the process of grafting polyethylene glycol (PEG), with molecular weights from 600 to 8000, to alumina powders was investigated. The maximum grafted amounts were achieved by the technique of dispersing the alumina powders in molten polymer at 195°C. The ungrafted PEG was then removed by repeated centrifuging and redispersion in fresh distilled water. The rheological behavior of suspensions of the PEG-grafted powders in water, 2-propanol and 2-butanol were characterized. All of the aqueous suspensions were shear thinning. The PEG 4600-grafted alumina powder aqueous suspensions were the most fluid. Sample rods and bars were molded from 52 vol% PEG-grafted alumina suspensions in 2-butanol. The best results were obtained with a preheated aluminum mold lubricated with a fluorinated oil mold-release. The samples were dried, sintered, and their microstructure and density were compared with sintered samples dry pressed from the same alumina powder

  11. Evaluation of Three-Dimensional Chitosan-Agarose-Gelatin Cryogel Scaffold for the Repair of Subchondral Cartilage Defects: An In Vivo Study in a Rabbit Model

    OpenAIRE

    Gupta, Ankur; Bhat, Sumrita; Jagdale, Pankaj R.; Bhushan P Chaudhari; Lidgren, Lars; Gupta, Kailash C.; Kumar, Ashok

    2014-01-01

    In this study, the potential of a chitosan-agarose-gelatin (CAG) cryogel scaffold for the repair of subchondral cartilage defects was explored in female New Zealand white rabbits. Custom-made CAG cryogel scaffold was implanted in a surgically created subchondral defect (diameter of 4 mm, depth of 4 mm) in knee joint of rabbit. The repair of the subchondral defect was evaluated at regular time interval by both macroscopic as well as microscopic examinations. The gross evaluation of the scaffol...

  12. Three-Dimensional Numerical Simulation of Mold Filling Process in Compression Resin Transfer Molding

    Science.gov (United States)

    Yang, Bo; Jin, Tianguo; Li, Jianguang; Bi, Fengyang

    2015-04-01

    Compression resin transfer molding (CRTM) is an effective process for the manufacturing of composite parts with large size and high fiber content, while the existence of open gap, the dynamically changing dimensions of cavity geometry and the deformation of preform during filling process bring great difficulties to the three-dimensional simulation of resin flow in CRTM. In order to develop a convenient and efficient three-dimensional simulation approach for CRTM filling process, a unified mathematical model for resin flow in both open gap and preform is established instead of considering the gap as high permeability preform, then the analysis of the clamping force and stress distribution are presented. In order to avoid direct solving the coupled equations of resin flow and cavity deformation, volume of fluid (VOF) multiphase flow technology and dynamic mesh model are applied to track the resin flow front and update the cavity geometry during filling simulation, respectively. The master-slave element method is used to modify the amount of resin release and ensure the resin mass conservation. The validity of the numerical approach is verified by comparison with analytical and experimental results, three-dimensional simulation examples are also presented.

  13. Molding Properties of Inconel 718 Feedstocks Used in Low-Pressure Powder Injection Molding

    Directory of Open Access Journals (Sweden)

    Fouad Fareh

    2016-01-01

    Full Text Available The impact of binders and temperature on the rheological properties of feedstocks used in low-pressure powder injection molding was investigated. Experiments were conducted on different feedstock formulations obtained by mixing Inconel 718 powder with wax-based binder systems. The shear rate sensitivity index and the activation energy were used to study the degree of dependence of shear rate and temperature on the viscosity of the feedstocks. The injection performance of feedstocks was then evaluated using an analytical moldability model. The results indicated that the viscosity profiles of feedstocks depend significantly on the binder constituents, and the secondary binder constituents play an important role in the rheological behavior (pseudoplastic or near-Newtonian exhibited by the feedstock formulations. Viscosity values as low as 0.06 to 2.9 Pa·s were measured at high shear rates and high temperatures. The results indicate that a feedstock containing a surfactant agent exhibits the best moldability characteristics.

  14. Computer precision simulation for titanium casting centrifugal mold filling of prescision titanium castings

    Directory of Open Access Journals (Sweden)

    Daming XU

    2004-08-01

    Full Text Available Computer simulation codes were developed based on proposed mathematical model for centrifugal mold filling processes and previous computer software for 3D mold filling and solidification of castings. Sample simulations were implemented for mold filling processes of precision titanium castings under gravity and different centrifugal casting techniques. The computation results show that the alloy melt has a much stronger mold filling ability for thin section castings unde a centrifugal force field than that only under the gravity. A "return back" mold filling manner is showed to be a reasonable technique for centrifugal casting processes, especially for thin section prcision castings.

  15. Measurement of casting parameters in ZnAlCu3 molds created by additive technology

    Directory of Open Access Journals (Sweden)

    S. Medić

    2016-10-01

    Full Text Available This paper examines the parameters of casting ZnAl4Cu3 alloy (volume, castability, density and occupancy of the mold in mold made additive technology. Molds made by additive technology are: cheaper in production of a small number of castings, geometrically more accurate and faster made. From obtained results of this paper it is clearly seen that printed mold must be protected with thermal coating because liquid adhesive of powder otherwise evaporates during casting and creates additional moisture in the mold, as it was noted.

  16. Temperature and Thermal Stress Distribution for Metal Mold in Squeeze Casting Process

    Institute of Scientific and Technical Information of China (English)

    K.H.Chang; G.C.Jang; C.H.Lee; S.H.Lee

    2008-01-01

    In the squeeze casting process, loaded high pressure (over approximately 100 MPa) and high temperature influence the thermo-mechanical behavior and performance of the used metal mold. Therefore, to safely maintain the metal molds, the thermo-mechanical characteristics (temperature and thermal stress) of metal mold in the squeeze casting must be investigated. In this paper, temperature and thermal stress distribution of steel mold in squeeze casting process were investigated by using a three-dimensional non-steady heat conduction analysis and a three-dimensional thermal elastic-plastic analysis considering temperature-dependent thermo- physical and mechanical properties of the steel mold.

  17. Tools for NEPA compliance: Baseline reports and compliance guides

    Energy Technology Data Exchange (ETDEWEB)

    Wolff, T.A. [Sandia National Labs., Albuquerque, NM (United States); Hansen, R.P. [Hansen Environmental Consultants, Englewood, CO (United States)

    1994-12-31

    Environmental baseline documents and NEPA compliance guides should be carried in every NEPA implementation ``tool kit``. These two indispensable tools can play a major role in avoiding repeated violations of NEPA requirements that have occurred over the past 26 years. This paper describes these tools, discusses their contents, and explains how they are used to prepare better NEPA documents more cost-effectively. Focus is on experience at Sandia Laboratories (NM).

  18. Aplicação de modelo matemático às propriedades reológicas de géis mistos de agarose e de goma guar Application of a mathematical model to the rheological properties of agarose-guar gum mixed gels

    Directory of Open Access Journals (Sweden)

    Cristina T. Andrade

    1997-04-01

    Full Text Available Certain biopolymers are capable of forming physically cross-linked gels in aqueous medium, stabilized by forces such as Coulombic, charge transfer, hydrogen bonding, dipole-dipole, van der Waals, and hydrophobic interactions. The mathematical description of these physical networks are difficult, but should contribute to a better understanding of the gelling process. The Clark and Ross-Murphy model was applied to experimental data for agarose-guar gum mixed systems, in which only agarose is the gelling polysaccharide. A computational routine based on the statistical maximum likehood principle was employed to estimate the f, K and a characteristic parameters. Statistical t-test and F-test were used to analyse the set of parameters.

  19. Effects of centrifugal and Coriolis forces on the mold-filling behavior of titanium melts in vertically rotating molds

    Institute of Scientific and Technical Information of China (English)

    Xu Daming; Jia Limin; Fu Hengzhi

    2008-01-01

    The vertical centrifugal-casting technique is widely used in the manufacture of various irregularly-shaped castings of advanced structural alloys with thin walls, complex shapes and/or large sizes. These castings are used in the increasing applications in aero-space/aviation industries, human teeth/bone repairs with near-net shaped components, etc. In a vertically rotating casting system, the mold-filling processes of alloy melts, coupled with solidification-heat transfer, may be much more complicated, because they are driven simultaneously by gravity, centrifugal and Codolis forces. In the present work, an N-S/VOF-equations-based model, solved using a SOLA-VOF algorithm, under a rotating coordinate system was applied to numerically investigate the impacts of centrifugal and Coriolis forces on metallic melt mold-filling processes in different vertical centrifugal-casting configurations with different mold-rotation rates using an authors' computer-codes system. The computational results show that the Coriolis force may cause remarkable variations in the flow patterns in the casting-part-cavities of a large horizontal-section area and directly connected to the sprue via a short ingate in a vertical centrifugal-casting process. A "turn-back" mold-filling technique, which only takes advantage of the centrifugal force in a transient rotating melt system, has been confirmed to be a rational centrifugal-casting process in order to achieve smooth and layer-by-layer casting-cavities-filling control. The simulated mold-filling processes of Ti-6Al-4V alloy melt, in a vertical centrifugal-casting system with horizontally-connected plate-casting cavities, show reasonable agreement with experimental results from the literature.

  20. EXPERIMENTAL MEASUREMENT OF MAGNETIC FIELD IN A NOVEL FLOW CONTROL OF MOLD

    Institute of Scientific and Technical Information of China (English)

    G.J. Xu; D.H. Li; J.C. He

    2002-01-01

    In order to know the distribution of magnetic field in a novel flow control of mold(NFC Mold) and to provide the experimental data for the electromagnetic structuredesign and the analysis of flow control in continuous casting mold, the magnetic fieldin a NFC Mold were measured by Tesla meter of Model CT-3. The method of vectorsynthesis was adopted in the measurement of magnetic fields. The results showed thatthe magnetic field in the NFC Mold was composed of two main magnetic areas thatwere symmetrical. Although there was leaking magnetic flux between the lower surfaceof the upper pole and the upper surface of the lower pole on the sides, it was restrainedby the main magnetic fields effectively. Therefore the NFC Mold was more preferablysatisfied to be used in controlling the molten steel flow in continuous casting mold.

  1. Increasing the life of molds for casting copper and its alloys

    Science.gov (United States)

    Smirnov, A. N.; Spiridonov, D. V.

    2010-12-01

    The work of the molds intended for casting copper and copper alloys in semicontinuous casters for producing flat billets is considered. It is shown that, to increase the resistance of mold plates, the inner space of the mold should have a taper shape toward the casting direction and take into account the shrinkage of the linear dimensions of the ingot during its motion in the mold. The taper shape increases the intensity and uniformity of heat removal due to close contact between the ingot and the mold inner surface. Testing of new design molds under industrial conditions demonstrates that their resistance increases by a factor of 4.0-4.5. The taper effect of the mold plates is much more pronounced in their narrow faces.

  2. EXPERIMENTAL RESEARCH AND NUMERICAL SIMULATION OF MOLD TEMPERATURE FIELD IN CONTINUOUS CASTING OF STEEL

    Institute of Scientific and Technical Information of China (English)

    X.S. Zheng; M.H. Sha; J.Z. Jin

    2006-01-01

    Mold is the heart of the continuous casting machine. Heat transfer and solidification in a watercooled mold are the most important factors during the continuous casting of steel. For studying the temperature distribution of a mold wall, a simulated apparatus of mold was designed and experiments were performed by it. The measured results indicated that the mold wall temperature approaches the temperature of cooling-water. An equivalent thermal-conductivity coefficient was proposed and deduced on the basis of the conclusion of the experiments. This coefficient was applied to solve the heat transfer between the melt and cooling water, and to characterize the heat transfer capacity of the mold. By this equivalent thermal-conductivity coefficient, it is very easy and convenient to numerically simulate the solidification process of continuous casting. And the calculation results are in agreement with the experiments. The effects of casting speed and water flow rate on the mold temperature field were also discussed.

  3. Modeling and flow analysis of pure nylon polymer for injection molding process

    Science.gov (United States)

    Nuruzzaman, D. M.; Kusaseh, N.; Basri, S.; Oumer, A. N.; Hamedon, Z.

    2016-02-01

    In the production of complex plastic parts, injection molding is one of the most popular industrial processes. This paper addresses the modeling and analysis of the flow process of the nylon (polyamide) polymer for injection molding process. To determine the best molding conditions, a series of simulations are carried out using Autodesk Moldflow Insight software and the processing parameters are adjusted. This mold filling commercial software simulates the cavity filling pattern along with temperature and pressure distributions in the mold cavity. In the modeling, during the plastics flow inside the mold cavity, different flow parameters such as fill time, pressure, temperature, shear rate and warp at different locations in the cavity are analyzed. Overall, this Moldflow is able to perform a relatively sophisticated analysis of the flow process of pure nylon. Thus the prediction of the filling of a mold cavity is very important and it becomes useful before a nylon plastic part to be manufactured.

  4. Environment and Safeguards Compliance Policy

    OpenAIRE

    Inter-American Development Bank (IDB)

    2006-01-01

    This Environment and Safeguards Compliance Policy was approved by the IDB's Board of Executive Directors on January 19, 2006. It supersedes the Bank's previous environment policy, which dated to 1979, and reinforces the environmental mandates of the Eighth Capital Replenishment. The new Policy strengthens the Bank's commitment with environmental sustainability in the region. This Policy consists of a set of directives that will guide the Bank's work towards environmental sustainability throug...

  5. Composite materials molding simulation for purpose of automotive industry

    Science.gov (United States)

    Grabowski, Ł.; Baier, A.; Majzner, M.; Sobek, M.

    2016-08-01

    Composite materials loom large increasingly important role in the overall industry. Composite material have a special role in the ever-evolving automotive industry. Every year the composite materials are used in a growing number of elements included in the cars construction. Development requires the search for ever new applications of composite materials in areas where previously were used only metal materials. Requirements for modern solutions, such as reducing the weight of vehicles, the required strength and vibration damping characteristics go hand in hand with the properties of modern composite materials. The designers faced the challenge of the use of modern composite materials in the construction of bodies of power steering systems in vehicles. The initial choice of method for producing composite bodies was the method of molding injection of composite material. Molding injection of polymeric materials is a widely known and used for many years, but the molding injection of composite materials is a relatively new issue, innovative, it is not very common and is characterized by different conditions, parameters and properties in relation to the classical method. Therefore, for the purpose of selecting the appropriate composite material for injection for the body of power steering system computer analysis using Siemens NX 10.0 environment, including Moldex 3d and EasyFill Advanced tool to simulate the injection of materials from the group of possible solutions were carried out. Analyses were carried out on a model of a modernized wheel case of power steering system. During analysis, input parameters, such as temperature, pressure injectors, temperature charts have been analysed. An important part of the analysis was to analyse the propagation of material inside the mold during injection, so that allowed to determine the shape formability and the existence of possible imperfections of shapes and locations air traps. A very important parameter received from

  6. Route 20, Autobahn 7, and Slime Mold: Approximating the Longest Roads in USA and Germany With Slime Mold on 3-D Terrains.

    Science.gov (United States)

    Adamatzky, Andrew I

    2014-01-01

    A cellular slime mould Physarum polycephalum is a monstrously large single cell visible by an unaided eye. The slime mold explores space in parallel, is guided by gradients of chemoattractants, and propagates toward sources of nutrients along nearly shortest paths. The slime mold is a living prototype of amorphous biological computers and robotic devices capable of solving a range of tasks of graph optimization and computational geometry. When presented with a distribution of nutrients, the slime mold spans the sources of nutrients with a network of protoplasmic tubes. This protoplasmic network matches a network of major transport routes of a country when configuration of major urban areas is represented by nutrients. A transport route connecting two cities should ideally be a shortest path, and this is usually the case in computer simulations and laboratory experiments with flat substrates. What searching strategies does the slime mold adopt when exploring 3-D terrains? How are optimal and transport routes approximated by protoplasmic tubes? Do the routes built by the slime mold on 3-D terrain match real-world transport routes? To answer these questions, we conducted pioneer laboratory experiments with Nylon terrains of USA and Germany. We used the slime mold to approximate route 20, the longest road in USA, and autobahn 7, the longest national motorway in Europe. We found that slime mold builds longer transport routes on 3-D terrains, compared to flat substrates yet sufficiently approximates man-made transport routes studied. We demonstrate that nutrients placed in destination sites affect performance of slime mold, and show how the mold navigates around elevations. In cellular automaton models of the slime mold, we have shown variability of the protoplasmic routes might depends on physiological states of the slime mold. Results presented will contribute toward development of novel algorithms for sensorial fusion, information processing, and decision making, and

  7. Route 20, Autobahn 7, and Slime Mold: Approximating the Longest Roads in USA and Germany With Slime Mold on 3-D Terrains.

    Science.gov (United States)

    Adamatzky, Andrew I

    2014-01-01

    A cellular slime mould Physarum polycephalum is a monstrously large single cell visible by an unaided eye. The slime mold explores space in parallel, is guided by gradients of chemoattractants, and propagates toward sources of nutrients along nearly shortest paths. The slime mold is a living prototype of amorphous biological computers and robotic devices capable of solving a range of tasks of graph optimization and computational geometry. When presented with a distribution of nutrients, the slime mold spans the sources of nutrients with a network of protoplasmic tubes. This protoplasmic network matches a network of major transport routes of a country when configuration of major urban areas is represented by nutrients. A transport route connecting two cities should ideally be a shortest path, and this is usually the case in computer simulations and laboratory experiments with flat substrates. What searching strategies does the slime mold adopt when exploring 3-D terrains? How are optimal and transport routes approximated by protoplasmic tubes? Do the routes built by the slime mold on 3-D terrain match real-world transport routes? To answer these questions, we conducted pioneer laboratory experiments with Nylon terrains of USA and Germany. We used the slime mold to approximate route 20, the longest road in USA, and autobahn 7, the longest national motorway in Europe. We found that slime mold builds longer transport routes on 3-D terrains, compared to flat substrates yet sufficiently approximates man-made transport routes studied. We demonstrate that nutrients placed in destination sites affect performance of slime mold, and show how the mold navigates around elevations. In cellular automaton models of the slime mold, we have shown variability of the protoplasmic routes might depends on physiological states of the slime mold. Results presented will contribute toward development of novel algorithms for sensorial fusion, information processing, and decision making, and

  8. Surviving freezing in plant tissues by oomycetous snow molds.

    Science.gov (United States)

    Murakami, Ryo; Yajima, Yuka; Kida, Ken-ichi; Tokura, Katsuyuki; Tojo, Motoaki; Hoshino, Tamotsu

    2015-04-01

    Oomyceteous snow molds, Pythium species, were reported to be less tolerant to chilling and freezing temperatures than other snow mold taxa. However, Pythium species are often found to be pathogenic on mosses in Polar Regions. We investigated the frost resistance of Pythium species from Temperate (Hokkaido, Japan) and Subantarctic Regions. Free mycelia and hyphal swellings, structures for survival, of Pythium iwayamai and Pythium paddicum lost viability within freeze-thaw 3 cycles; however, mycelia in host plants survived the treatment. It was reported that fungi in permafrost are characterized both by the presence of natural cryoprotectants in these ecotopes and by the ability to utilize their inherent mechanisms of protection. It is conceivable that plant substrates or derivatives thereof are natural cryoprotectants, enabling them to provide advantageous conditions to microorganisms under freezing conditions. Our results are the first to experimentally support this hypothesis.

  9. Modeling and simulation of heat transfer for glass bulb mold

    Institute of Scientific and Technical Information of China (English)

    ZHOU Huamin; LI Dequn

    2005-01-01

    Cooling system design in glass bulb pressing operation can greatly affect the productivity and the quality of the final product. The concept of cyclic-averaged steady temperature field is proposed in modeling. Heat transfer in the mold region is considered to be a cyclic-steady, three-dimensional conduction; heat transfer within the glass melt region is treated as a transient, one-dimensional conduction; heat exchange between the cooling system surface and coolant is treated as a steady heat convection. A hybrid model consisting of a three-dimensional boundary element method for the mold region and a finite-difference method with a variable mesh for the melt region is used for numerical simulation. Compared with the experimental data, the numerical model developed here is computationally efficient and sufficiently accurate.

  10. Characteristics of shell thickness in a slab continuous casting mold

    Institute of Scientific and Technical Information of China (English)

    Di-feng Wu; Shu-sen Cheng; Zi-jian Cheng

    2009-01-01

    The key to reduce shell breakout in the continuous casting process is to control shell thickness in the mold.A numerical simulation on the turbulent flow and heat transfer coupled with solidification in the slab mold using the volume of fluid (VOF) model and the enthalpy-porosity scheme was conducted and the emphasis was put upon the flow effect on the shell thickness profiles in longitudinal and transverse directions.The results show that the jet acts a stronger impingement on the shell of narrow face,which causes a zero-increase of shell thickness in a certain range near the impingement point.The thinnest shell on the slab cross-section locates primarily in the center of the narrow face,and secondly near the comer of the wide face.Nozzle optimization can obviously increase the shell thickness and make it more uniform.

  11. FPGA-Based Multiprocessor System for Injection Molding Control

    Directory of Open Access Journals (Sweden)

    Roque A. Osornio-Rios

    2012-10-01

    Full Text Available The plastic industry is a very important manufacturing sector and injection molding is a widely used forming method in that industry. The contribution of this work is the development of a strategy to retrofit control of an injection molding machine based on an embedded system microprocessors sensor network on a field programmable gate array (FPGA device. Six types of embedded processors are included in the system: a smart-sensor processor, a micro fuzzy logic controller, a programmable logic controller, a system manager, an IO processor and a communication processor. Temperature, pressure and position are controlled by the proposed system and experimentation results show its feasibility and robustness. As validation of the present work, a particular sample was successfully injected.

  12. Pressureless sintering behavior of injection molded alumina ceramics

    Directory of Open Access Journals (Sweden)

    Liu W.

    2014-01-01

    Full Text Available The pressureless sintering behaviors of two widely used submicron alumina (MgOdoped and undoped with different solid loadings produced by injection molding have been studied systematically. Regardless of the sinterability of different powders depending on their inherent properties, solid loading plays a critical role on the sintering behavior of injection molded alumina, which greatly determines the densification and grain size, and leads to its full densification at low temperatures. As compared to the MgO-doped alumina powder, the undoped specimens exhibit a higher sinterability for its smaller particle size and larger surface area. While full densification could be achieved for MgO-doped powders with only a lower solid loading, due to the fact that MgO addition can reduce the detrimental effect of the large pore space on the pore-boundary separation.

  13. Grain Refinement of Permanent Mold Cast Copper Base Alloys

    Energy Technology Data Exchange (ETDEWEB)

    M.Sadayappan; J.P.Thomson; M.Elboujdaini; G.Ping Gu; M. Sahoo

    2005-04-01

    Grain refinement is a well established process for many cast and wrought alloys. The mechanical properties of various alloys could be enhanced by reducing the grain size. Refinement is also known to improve casting characteristics such as fluidity and hot tearing. Grain refinement of copper-base alloys is not widely used, especially in sand casting process. However, in permanent mold casting of copper alloys it is now common to use grain refinement to counteract the problem of severe hot tearing which also improves the pressure tightness of plumbing components. The mechanism of grain refinement in copper-base alloys is not well understood. The issues to be studied include the effect of minor alloy additions on the microstructure, their interaction with the grain refiner, effect of cooling rate, and loss of grain refinement (fading). In this investigation, efforts were made to explore and understand grain refinement of copper alloys, especially in permanent mold casting conditions.

  14. Residue stress analysis of molding aspherical plastic lens

    Science.gov (United States)

    Hsu, Ming-Ying; Cheng, Yuan-Chieh; Chang, Shenq-Tsong; Huang, Ting-Ming

    2015-09-01

    The aspherical plastic lens is widely used in commercial optical products. Warpage and residue stress are two important factors that influence wavefront error. Several investigators have discussed warpage. We propose a methodology to study the effect of residue stress on wavefront error. Mold flow software was adopted to calculate the residue stress in injection processes. Optical software was used to find optical ray paths through the lens. Corresponding Optical Path Different (OPD) in each ray path was simulated by self-developed software. A 50-mm diameter plastic lens was used in this study. The mild- and high-frequency wavefront errors and the stress OPD effect at the injection area were found to be a result of the molding process. The proposed methodology was found to be very suitable for finding the effect of residue stress on wavefront error in plastic lenses.

  15. Cavity air flow behavior during filling in microinjection molding

    DEFF Research Database (Denmark)

    Griffiths, C.A.; Dimov, S.S.; Scholz, S.;

    2011-01-01

    valuable information about the process dynamics and also about the filling of a cavity by a polymer melt. In this paper, a novel experimental setup is proposed to monitor maximum air flow and air flow work as an integral of the air flow over time by employing a microelectromechanical system gas sensor...... mounted inside the mold. The influence of four μIM parameters, melt temperature, mold temperature, injection speed, and resistance to air evacuation, on two air flow-related output parameters is investigated by carrying out a design of experiment study. The results provide empirical evidences about...... the effects of process parameters on cavity air evacuation, and the influence of air evacuation on the part flow length. © 2011 American Society of Mechanical Engineers....

  16. Reusable molds for casting U-Zr alloys

    International Nuclear Information System (INIS)

    Refractory oxides, carbides, nitrides and sulfides were examined as mold coating materials for use in casting nuclear fuel. The molds require excellent high temperature chemical and mechanical stability combined with reasonable room temperature ductility to allow for fuel removal. Coatings were applied onto quartz and refractory metal coupons using various techniques. Sessile drop tests employing molten U-10%Zr (by weight) at 1550 degrees C were used to characterize coating performance. Results indicate that NbC, TiN, and Y2O3 were non-wetting with U-10%Zr. However, only the Y2O3 coating completely prevented adhesion of the fuel. The paper describes coating methods and details of the sessile drop experiments

  17. Fabrication of Complex Optical Components From Mold Design to Product

    CERN Document Server

    Riemer, Oltmann; Gläbe, Ralf

    2013-01-01

    High quality optical components for consumer products made of glass and plastic are mostly fabricated by replication. This highly developed production technology requires several consecutive, well-matched processing steps called a "process chain" covering all steps from mold design, advanced machining and coating of molds, up to the actual replication and final precision measurement of the quality of the optical components. Current market demands for leading edge optical applications require high precision and cost effective parts in large volumes. For meeting these demands it is necessary to develop high quality process chains and moreover, to crosslink all demands and interdependencies within these process chains. The Transregional Collaborative Research Center "Process chains for the replication of complex optical elements" at Bremen, Aachen and Stillwater worked extensively and thoroughly in this field from 2001 to 2012. This volume will present the latest scientific results for the complete process chain...

  18. Selection of Thermotropic Liquid Crystalline Polymers for Rotational Molding

    OpenAIRE

    Scribben, Eric Christopher

    2004-01-01

    Thermotropic liquid crystalline polymers (TLCPs) possess a number of physical and mechanical properties such as: excellent chemical resistance, low permeability, low coefficient of thermal expansion, high tensile strength and modulus, and good impact resistance, which make them desirable for use in the storage of cryogenic fluids. Rotational molding was selected as the processing method for these containers because it is convenient for manufacturing large storage vessels from thermoplastics....

  19. Presurgical nasoalveolar molding in unilateral cleft lip and palate

    Directory of Open Access Journals (Sweden)

    Rahul J Hegde

    2015-01-01

    Full Text Available Unilateral cleft lip and palate (UCLP patients have an esthetic and functional compromise of the middle third of the face and nasal structures. To improve the esthetic result of lip repair, the concept of presurgical nasoalveolar molding (PNAM was brought into conception. PNAM is an easy and passive method of bringing the alveolus and lips together by redirecting the forces of natural growth. This case report documents a 2-year follow-up of PNAM in UCLP.

  20. Presurgical nasoalveolar molding in unilateral cleft lip and palate

    Science.gov (United States)

    Hegde, Rahul J.; Kharkar, Viraj R.; Kamath, Shamika

    2015-01-01

    Unilateral cleft lip and palate (UCLP) patients have an esthetic and functional compromise of the middle third of the face and nasal structures. To improve the esthetic result of lip repair, the concept of presurgical nasoalveolar molding (PNAM) was brought into conception. PNAM is an easy and passive method of bringing the alveolus and lips together by redirecting the forces of natural growth. This case report documents a 2-year follow-up of PNAM in UCLP. PMID:26681868

  1. Metal Injection Molding (MIM) of Magnesium and Its Alloys

    OpenAIRE

    Martin Wolff; Johannes G. Schaper; Marc René Suckert; Michael Dahms; Frank Feyerabend; Thomas Ebel; Regine Willumeit-Römer; Thomas Klassen

    2016-01-01

    Current research has highlighted that magnesium and its alloys as biodegradable material are highly suitable for biomedical applications. The new material fully degrades into nontoxic elements and offers material properties matching those of human bone tissue. As biomedical implants are rather small and complex in shape, the metal injection molding (MIM) technique seems to be well suited for the near net shape mass production of such parts. Furthermore, MIM of Mg-alloys is of high interest in...

  2. Tackification of textile preforms for resin transfer molding

    Institute of Scientific and Technical Information of China (English)

    Wuyunqiqige; YI; Xiao-su

    2005-01-01

    Tackified textile fiber preforms are used widely in resin transfer molding (RTM) to produce aerospace-grade composite parts. In the present study, a new tackifier was developed to improve RTM laminate performance. The influence of tackifier concentration on spring back, thermal properties and mechanical performance was studied . It has showed that the new tackifier was compatible with the matrix resin and improved the textile handling ability; the ILSS was slightly increased without decreasing of thermal properties, modulus and flexural strength.

  3. Structure of turbulent flow in a slab mold

    Science.gov (United States)

    Ramírez-López, Pável; Demedices, L. G.; Dávila, O.; Sánchez-Pérez, R.; Morales, R. D.

    2005-12-01

    The structure of the turbulent flow in a slab mold is studied using a water model, various experimental techniques, and mathematical simulations. The meniscus stability depends on the turbulence structure of the flow in the mold; mathematical simulations using the k-ɛ model and the Reynolds-stress model (RSM) indicate that the latter is better at predicting the meniscus profile for a given casting speed. Reynolds stresses and flow vorticity measured through the particle-image velocimetry (PIV) technique are very close to those predicted by the RSM model, and maximum and minimum values across the jet diameter are reported. The backflow in the upper side of the submerged entry nozzle (SEN) port (for a fixed SEN design) depends on the casting speed and disappears, increasing this process parameter. At low casting speeds, the jet does not report enough dissipation of energy, so the upper flow roll is able to reach the SEN port. At high casting speeds, the jet energy is strongly dissipated inside the SEN port, the narrow wall, and in the mold corner, weakening the momentum transfer of the upper flow roll, which is unable to reach the SEN port. At low casting speeds, meniscus instability is observed very close to the SEN, while at high casting speeds, this instability is observed in the mold corner. An optimum casting speed is reported where complete meniscus stability was observed. The flow structure at the free surface indicates a composite structure of islands with large gradients of velocity at high casting speeds. These velocity gradients are responsible for the meniscus instability.

  4. Compacting Plastic-Bonded Explosive Molding Powders to Dense Solids

    Energy Technology Data Exchange (ETDEWEB)

    B. Olinger

    2005-04-15

    Dense solid high explosives are made by compacting plastic-bonded explosive molding powders with high pressures and temperatures for extended periods of time. The density is influenced by manufacturing processes of the powders, compaction temperature, the magnitude of compaction pressure, pressure duration, and number of repeated applications of pressure. The internal density variation of compacted explosives depends on method of compaction and the material being compacted.

  5. Numerical Simulation and Water Analog of Mold Filling Processes

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    This paper demonstrates the potential of a computer code, developed by the authors, in shaping gating systems by modeling the fluid flow phenomena through a complex gating system during mold filling. A plate casting with dimension 200 mm×200 mm×50 mm was chosen as the verifying problem. Water analog studies were carried out on this casting. The comparison indicates that computer simulation could be a powerful tool in shaping gating systems.

  6. ''Heat Transfer at the Mold-Metal Interface in Permanent Mold Casting of Aluminum Alloys'' Final Project Report

    Energy Technology Data Exchange (ETDEWEB)

    Professor R. D. Pehlke, Principal Investigator, Dr. John M. Cookson, Dr. Shouwei Hao, Dr. Prasad Krishna, Kevin T. Bilkey

    2001-12-14

    This project on heat transfer coefficients in metal permanent mold casting has been conducted in three areas. They are the theoretical study at the University of Michigan, the experimental investigation of squeeze casting at CMI-Tech Center (Now Hayes-Lemmerz Technical Center) and the experimental investigation of low pressure permanent mold casting at Amcast Automotive.

  7. Compliance management and corporate governance; Compliance Management und Corporate Governance

    Energy Technology Data Exchange (ETDEWEB)

    Becker, Uwe [Stadt Frankfurt am Main (Germany); Alsheimer, Constantin; Kassebohm, Kristian; Reutler, Susanne [Mainova AG, Frankfurt (Germany)

    2009-08-15

    Starting in the year 2009, numerous changes in the financial system and accountancy a well as in the corporate law come into effect for enterprises. Thereby, the requirements substantially are intensified to their corporate governance. The actual well-known reproaches of bribery, corruption and injuries of data protection intensify the pressure on executive committees and supervisory boards in order to meet normative and ethical requirements. All the more is valid for power suppliers whose reputation can already carry damage out with the first suspicion. Already in 2008, Mainova AG (Frnkfurt/Main, Federal Republic of Germany) implemented a compliance management.

  8. Influence of the Mold Current on the Electroslag Remelting Process

    Science.gov (United States)

    Hugo, Mathilde; Dussoubs, Bernard; Jardy, Alain; Escaffre, Jessica; Poisson, Henri

    2016-08-01

    The electroslag remelting process is widely used to produce high value-added alloys. The use of numerical simulation has proven to be a valuable way to improve its understanding. In collaboration with Aubert & Duval, the Institute Jean Lamour has developed a numerical transient model of the process. The consumable electrode is remelted within a mold assumed to be electrically insulated by the solidified slag skin. However, this assumption has been challenged by some recent studies: the solidified slag skin may actually allow a part of the melting current to reach the mold. In this paper, the evolution of our model, in order to take into account this possibility, is presented and discussed. Numerical results are compared with experimental data, while several sensitivity studies show the influence of some slag properties and operating parameters on the quality of the ingot. Even, a weakly conductive solidified slag skin at the inner surface of the mold may be responsible for a non-negligible amount of current circulating between the slag and crucible, which in turn modifies the fluid flow and heat transfer in the slag and ingot liquid pool. The fraction of current concerned depends mainly on the electrical conductivities of both the liquid and solidified slag.

  9. Occurrence of Foodborne Pathogens and Molds in Turkish Foods

    Directory of Open Access Journals (Sweden)

    Sebnem Ozturkogu-Budak

    2016-07-01

    Full Text Available A survey of the occurrence of food pathogens like Salmonella, Listeria, Escherichia, Clostridium, Bacillus and Staphylococcus analyses were performed on 301 food samples from 8 different food categories such as dry legumes, milk products, meat products, fish, frozen foods, deserts, nuts and vegetables and fruits. Yeast and mold analyses were also performed on 364 food products from 9 main food categories such as dry legumes, milk products, meat products, seasonings, deserts, nuts, bee products, bakery products and dried fruits produced in Turkey. S. aureus and Salmonella were the most prevalent (1.33% of the six isolated pathogens. The species Cl. perfringens, L. monocytogenes and B. cereus were detected with the ratios of 1.00%, 0.66% and 0.66%, respectively. Total yeast and molds occurrence were 1.65% and 9.06%, respectively. Pathogens were detected in cream cheese, spinach, strawberry and cod fish most prevalently, whereas dried fig, chilli pepper, hazelnut and bakery products were determined as foods prone to the growth of molds. The results of this study suggest that faecal contamination of water needs to be prevented, and the production and storage conditions of food materials should be improved. These findings have implications for the use of these surveillance data in developing evidence-based food policy.

  10. Drag material change in hot runner injection molding

    Institute of Scientific and Technical Information of China (English)

    蒋炳炎; 黄伯云

    2001-01-01

    Quick material change is often encountered for the different colors or kinds of polymer in hot runner injecting molding process. Time-costing and incompleteness of material change process often affects the quality and productivity of products. In the practical production, multi-injection or white material as the transition material is often adopted for quick material change. Based on the rheological behavior of the new and the previous plastic melt, the researches on the related problems were carried out. The concept of drag material change was originally presented. The physical and mathematical model on the simultaneous flow process of the new and the previous plastic melt in hot runner were built up, which can well explain the influence of the injection speed, pressure, viscosity difference, temperature and mold structure on the drag material change efficiency. When temperature in different position in the mold was increased and adjusted, the viscosity difference between the two kinds of melt can be controlled. Therefore the material change ability can be greatly improved during the whole material change process, getting rid of more and more difficult changing in the late stage.

  11. Modeling injection molding of net-shape active ceramic components.

    Energy Technology Data Exchange (ETDEWEB)

    Baer, Tomas (Gram Inc.); Cote, Raymond O.; Grillet, Anne Mary; Yang, Pin; Hopkins, Matthew Morgan; Noble, David R.; Notz, Patrick K.; Rao, Rekha Ranjana; Halbleib, Laura L.; Castaneda, Jaime N.; Burns, George Robert; Mondy, Lisa Ann; Brooks, Carlton, F.

    2006-11-01

    To reduce costs and hazardous wastes associated with the production of lead-based active ceramic components, an injection molding process is being investigated to replace the current machining process. Here, lead zirconate titanate (PZT) ceramic particles are suspended in a thermoplastic resin and are injected into a mold and allowed to cool. The part is then bisque fired and sintered to complete the densification process. To help design this new process we use a finite element model to describe the injection molding of the ceramic paste. Flow solutions are obtained using a coupled, finite-element based, Newton-Raphson numerical method based on the GOMA/ARIA suite of Sandia flow solvers. The evolution of the free surface is solved with an advanced level set algorithm. This approach incorporates novel methods for representing surface tension and wetting forces that affect the evolution of the free surface. Thermal, rheological, and wetting properties of the PZT paste are measured for use as input to the model. The viscosity of the PZT is highly dependent both on temperature and shear rate. One challenge in modeling the injection process is coming up with appropriate constitutive equations that capture relevant phenomenology without being too computationally complex. For this reason we model the material as a Carreau fluid and a WLF temperature dependence. Two-dimensional (2D) modeling is performed to explore the effects of the shear in isothermal conditions. Results indicate that very low viscosity regions exist near walls and that these results look similar in terms of meniscus shape and fill times to a simple Newtonian constitutive equation at the shear-thinned viscosity for the paste. These results allow us to pick a representative viscosity to use in fully three-dimensional (3D) simulation, which because of numerical complexities are restricted to using a Newtonian constitutive equation. Further 2D modeling at nonisothermal conditions shows that the choice of

  12. Characterization of mold and moisture indicators in the home.

    Science.gov (United States)

    Mahooti-Brooks, Negar; Storey, Eileen; Yang, Chin; Simcox, Nancy J; Turner, William; Hodgson, Michael

    2004-12-01

    As studies increasingly support the presence of health risks associated with mold and moisture, understanding fungal concentrations and physical measurements as they relate to the microenvironment becomes more important. We conducted a cross-sectional study in the homes of 64 subjects. The primary objective of this study was to use trained inspectors' list of indicators in rooms (bathroom, bedroom, and basement) and determine whether these indicators are associated with higher fungal levels or physical measurements. A new category for combining the concentrations of fungal species, referred to as moisture indicator fungi (MIF), is used in the analysis. Our results show that basements with a musty odor, efflorescence, water sources, or mold have a two- to threefold increase in fungal concentrations over basements without these indicators. The regression model for the basement was highly predictive of indoor MIF concentrations (r2 = .446, p = .017). Basement water sources are substantial predictors of indoor total fungi, MIF, and Aspergillus/Penicillium spp. MIF concentrations are higher in homes with basement water sources, and most notably, the increase in MIF concentrations is significant in other living spaces (bathroom and bedroom) of the dwelling. Basement water sources are important moisture/mold indicators for epidemiologists to use in exposure assessments performed in residential dwellings.

  13. Penerapan Standarisasi Desain untuk Meningkatkan Kualitas dan Masa Pakai Mold Di PT. Takagi Sari Multi Utama

    Directory of Open Access Journals (Sweden)

    Andi Widodo

    2014-10-01

    Full Text Available PT. Takagi Sari Multi Utama adalah perusahaan manufaktur yang bergerak di bidang injeksi plastik untuk produk otomotif terutama pada kendaraan bermotor. Karena begitu banyaknya pelanggan yang mempercayakan produk plastik injectionnya, maka PT. Takagi Sari Multi Utama harus memperhatikan mold yang digunakan sebagai sarana atau alat produksi memiliki kualitas yang tinggi. Karena begitu pentingnya suatu kualitas mold dan daya tahan mold terhadap penjaminan kualitas produksi, maka penulis mencari masalah utama yang terjadi PT. takagi Sari Multi Utama dengan menggunakan diagram pareto. Berdasarkan diagram terebut diperoleh data penyebap kerusakan mold paling tinggi adalah Design and Mold Structur dengan 154 Kejadian. Masalah Design and Mold Structur dipetakan dalam fishbone diagram untuk mengetahui permasalahan apa saja yang menyebapkan. Permasalahan yang ditemukan dilakukan analisa menggunakan FMEA (Failure Mode and Efect Analisis sebagai landasan melakukan perbaikan. Dengan metoda FMEA (Failure Mode and Efect Analisis diperoleh kesimpulan bahwa buruknya desain dan kontruksi mold dikarenakan tidak adanya standar desain yang digunakan sebagai acuhan proses desain dan pemeriksaan mold saat proses manufacturing dengan nilai RPN 567. Oleh karena itu proses perbaikan dilakukan dengan membuat standar desain mold di PT. Takagi Sari Multi Utama kemudian mencoba menerapkannya pada desain mold Cover Side 3/4.

  14. Environmental mold and mycotoxin exposures elicit specific cytokine and chemokine responses.

    Directory of Open Access Journals (Sweden)

    Jamie H Rosenblum Lichtenstein

    Full Text Available Molds can cause respiratory symptoms and asthma. We sought to use isolated peripheral blood mononuclear cells (PBMCs to understand changes in cytokine and chemokine levels in response to mold and mycotoxin exposures and to link these levels with respiratory symptoms in humans. We did this by utilizing an ex vivo assay approach to differentiate mold-exposed patients and unexposed controls. While circulating plasma chemokine and cytokine levels from these two groups might be similar, we hypothesized that by challenging their isolated white blood cells with mold or mold extracts, we would see a differential chemokine and cytokine release.Peripheral blood mononuclear cells (PBMCs were isolated from blood from 33 patients with a history of mold exposures and from 17 controls. Cultured PBMCs were incubated with the most prominent Stachybotrys chartarum mycotoxin, satratoxin G, or with aqueous mold extract, ionomycin, or media, each with or without PMA. Additional PBMCs were exposed to spores of Aspergillus niger, Cladosporium herbarum and Penicillium chrysogenum. After 18 hours, cytokines and chemokines released into the culture medium were measured by multiplex assay. Clinical histories, physical examinations and pulmonary function tests were also conducted. After ex vivo PBMC exposures to molds or mycotoxins, the chemokine and cytokine profiles from patients with a history of mold exposure were significantly different from those of unexposed controls. In contrast, biomarker profiles from cells exposed to media alone showed no difference between the patients and controls.These findings demonstrate that chronic mold exposures induced changes in inflammatory and immune system responses to specific mold and mycotoxin challenges. These responses can differentiate mold-exposed patients from unexposed controls. This strategy may be a powerful approach to document immune system responsiveness to molds and other inflammation-inducing environmental agents.

  15. Methods of Automatic Parting Mold and Manual Parting Mold for Injection Mold Design Based on UG%基于UG注射模设计的自动分模和手动分模方法

    Institute of Scientific and Technical Information of China (English)

    董海涛

    2012-01-01

    UG software is widely applied in plastic injection mold design,the basic principle of parting mold is introduced in this paper,and the UG application in plastic injection mold design is studied with a concrete case.The process of automatic parting mold and manual parting mold in UG are expatiated,the flexible application of two methods will significantly reduce mold design time and greatly improve the efficiency of injection mold design.%UG软件广泛地应用在注射模设计中,本文介绍了分模原理,并结合实例研究UG软件在注射模设计中的应用。介绍了自动分模和手动分模方法,两种方法的灵活应用可以缩短模具设计周期,提高注射模设计的效率。

  16. Optimization of Injection Mold Gate Location of Auto Parts Based on MoldFlow%基于MoldFlow的汽车配件注射模的浇口位置优化

    Institute of Scientific and Technical Information of China (English)

    冯桂香; 金叶明; 蒋飞龙

    2012-01-01

    Based on the analysis of examples to illustrate how to use the professional moldFlow analysis software MoldFlow solve real production problems in the gate location optimization, using MoldFlow software can be detected early in the design stage of the defective product and mold design, timely amendment to optimize designed to ensure the molding quality, shorten the construction period and reduce costs.%通过对实例的分析,说明如何运用专业模流分析软件MoldFlow解决实际生产中浇口位置优化的问题,利用MoldFlow软件能在设计阶段及早发现产品和模具设计的缺陷,及时修正,达到优化设计、保证成型质量、缩短工期、降低成本的目的。

  17. Internal compliance investigations can reduce government sanctions.

    Science.gov (United States)

    Mustokoff, M M; Yecies, M S

    1997-10-01

    An effective corporate compliance program is facilitated by three essential elements: a well-qualified compliance officer; a policy of immediate investigation of every report of potential fraud and abuse; and clearly defined roles for both corporate and outside counsel in conducting the investigations. A government agency is less likely to exercise the full extent of its powers when these elements are in place and three is evidence of a sincere compliance effort.

  18. Automated Security Compliance Tool for the Cloud

    OpenAIRE

    Ullah, Kazi Wali

    2012-01-01

    Security, especially security compliance, is a major concern that is slowing down the large scale adoption of cloud computing in the enterprise environment. Business requirements, governmental regulations and trust are among the reasons why the enterprises require certain levels of security compliance from cloud providers. So far, this security compliance or auditing information has been generated by security specialists manually. This process involves manual data collection and assessment wh...

  19. Monitoring managers through corporate compliance programs

    OpenAIRE

    Angelucci, C.; Han, M.A.

    2010-01-01

    Compliance programs entail monitoring of employees' behavior with the claimed objective of fighting corporate crime. (Competition) Authorities promote such intra-firm monitoring. In a three-tier hierarchy model, authority-shareholder-manager, we study the impact of monitoring through a compliance program on contracting within the firm and the authority's optimal sanctions and leniency policy. We find that compliance programs are beneficial in the fight against corporate crime if and only if t...

  20. Permit Compliance System (PCS) and Integrated Compliance Information System (ICIS) Widget

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Permit Compliance System (PCS) and Integrated Compliance Information System (ICIS) widget allows users to enter a specific geography and retrieve companies that...

  1. Speciation of lead in seawater and river water by using Saccharomyces cerevisiae immobilized in agarose gel as a binding agent in the diffusive gradients in thin films technique

    Energy Technology Data Exchange (ETDEWEB)

    Pescim, Guilherme Favoreto; Marrach, Gabriela; Vannuci-Silva, Monizze; Souza, Lais Alves; Menegario, Amauri Antonio [Universidade Estadual Paulista, Centro de Estudos Ambientais, Rio Claro, SP (Brazil)

    2012-09-15

    Saccharomyces cerevisiae immobilized in agarose gel is proposed as a binding agent for the diffusive gradients in thin films (DGT) technique for determination of Pb in river water and seawater. DGT samplers were assembled with the proposed binding agent (25-mm disk containing 20 %, m/v, S. cerevisiae and 3.0 %, m/v, agarose) and a diffusive layer of cellulose (3MM Chr chromatography paper of 25-mm diameter). The effects of some DGT parameters (e.g., immersion time, ionic strength, and pH) were evaluated. Elution of Pb from the binding agent was effectively done with 1.75 mol L{sup -1} HNO{sub 3}. The deployment curve (between 2 and 24 h) was characterized by a significant uptake of Pb (346 ng Pb h{sup -1}) and good linear regression (R {sup 2} = 0.9757). The experimental results are in excellent agreement with the predicted theoretical curve for mass uptake. Consistent results were found for solutions with ionic strengths of 0.005 mol L{sup -1} or greater and within a pH range of 4.5-8.5. Interferences from Cu (20:1), Mn (20:1), Fe (20:1), Zn (20:1), Ca (250:1), and Mg (250:1) in Pb retention were negligible. Determination of Pb in spiked river water samples (from the Corumbatai and Piracicaba rivers) performed using the proposed device was in agreement with total dissolved Pb, whereas measurements in seawater suggest that of the various species of Pb present in the samples, only cationic Pb species are adsorbed by the agarose-yeast gel disks. The in situ concentration of Pb obtained at two different sites of the Rio Claro stream (Corumbatai basin) were 1.13 {+-} 0.01 and 1.34 {+-} 0.04 {mu}g L{sup -1}. For 72-h deployments, a detection limit of 0.75 {mu}g L{sup -1} was calculated. The combination of inductively coupled plasma optical emission spectroscopy and in situ deployments of DGT samplers during the 72-h period makes possible the determination of labile Pb in river water. (orig.)

  2. Federal government expands compliance initiatives.

    Science.gov (United States)

    Dugan, J K

    1997-09-01

    In 1995, the Federal government initiated Operation Restore Trust to increase enforcement of fraud and abuse regulations in Medicare and Medicaid programs. With the success of the original initiative, the government is expanding the project to additional states and program areas. The initial scrutiny of home health agencies, nursing homes, hospice care, and durable medical equipment is being expanded to managed care plans and acute care hospitals with an eye toward DRG creep. To manage this increased enforcement activity, healthcare organizations should institute comprehensive corporate compliance programs. Such programs should provide a framework that delineates responsibilities and provides a systematic means to resolve issues in a timely manner.

  3. Strategies for Addressing Spreadsheet Compliance Challenges

    CERN Document Server

    Weber, Brandon

    2006-01-01

    Most organizations today use spreadsheets in some form or another to support critical business processes. However the financial resources, and developmental rigor dedicated to them are often minor in comparison to other enterprise technology. The increasing focus on achieving regulatory and other forms of compliance over key technology assets has made it clear that organizations must regard spreadsheets as an enterprise resource and account for them when developing an overall compliance strategy. This paper provides the reader with a set of practical strategies for addressing spreadsheet compliance from an organizational perspective. It then presents capabilities offered in the 2007 Microsoft Office System which can be used to help customers address compliance challenges.

  4. Theory of Regulatory Compliance for Requirements Engineering

    CERN Document Server

    Jureta, Ivan; Mylopoulos, John; Perini, Anna; Susi, Angelo

    2010-01-01

    Regulatory compliance is increasingly being addressed in the practice of requirements engineering as a main stream concern. This paper points out a gap in the theoretical foundations of regulatory compliance, and presents a theory that states (i) what it means for requirements to be compliant, (ii) the compliance problem, i.e., the problem that the engineer should resolve in order to verify whether requirements are compliant, and (iii) testable hypotheses (predictions) about how compliance of requirements is verified. The theory is instantiated by presenting a requirements engineering framework that implements its principles, and is exemplified on a real-world case study.

  5. MoldFlow软件综合分析在模具设计及制造中的应用%Application of MoldFlow Software Compositive Analysis in the Mold Design and Manufacture

    Institute of Scientific and Technical Information of China (English)

    张晓陆

    2009-01-01

    详细阐述了MoldFlow技术的重要作用及地位,介绍了MPI分析模块的作用,通过应用MoldFlow/MPI软件对下壳体模具进行CAE综合分析,显示了MoldFlow技术在模具开发过程中对于优化塑料制品设计,优化注射模设计和优化注射工艺参数等方面所起到的显著作用.

  6. MoldFlow软件在下壳体模具设计及制造中的应用%Application of MoldFlow Software in the Lower Shell Mold Design & Manufacture

    Institute of Scientific and Technical Information of China (English)

    张晓陆

    2008-01-01

    详细阐述了MoldFlow技术的重要作用及地位,介绍了MPI分析模块的作用,通过应用MoldFlow/MPI软件对下壳体模具进行CAE综合分析,显示了MoldFlow技术在模具开发过程中对于优化塑料制品设计、优化塑料模设计和优化注射工艺参数等方面所起到的显著作用.

  7. A model for mold collaborative manufacturing execution system based on Web Service

    Institute of Scientific and Technical Information of China (English)

    Zhao Lizhong; Wang Yanbin; Gao Guoan

    2006-01-01

    Mold manufacturing Extended Enterprise (EE) has the following characteristics: distributed in locality, tight cooperation and frequent information exchange. It needs a collaborative, highly efficient, reliable and intelligent manufacturing management system. The background of the Collaborative Manufacturing is introduced. A mold Collaborative Manufacturing Execution System (c-MES) is proposed. The feature of Web Service platform is analyzed. The necessity and feasibility of importing the Web Service to mold c-MES are discussed. Based on Web Service, the model of mold c-MES is built. Every module's function is described in detail, including the functions it supplies and the mechanism of information interaction among them. The feasibility of mold c-MES model is validated by a real mold manufacturing case.

  8. The Shrinkage Behavior and Surface Topographical Investigation for Micro Metal Injection Molding

    DEFF Research Database (Denmark)

    Islam, Aminul; Giannekas, Nikolaos; Marhöfer, David Maximilian;

    2014-01-01

    on the feature dimensions and also on the process conditions. A thin section of the part exhibits higher relative shrinkage compared with a thicker section. Based on these findings, it can be concluded that a micro part molded by MIM process will have higher relative shrinkage compared to a macro part made......Metal injection molding (MIM) is a near net shape manufacturing technology that can produce highly complex and dimensionally stable parts for high end engineering applications. Despite the recent growth and industrial interest, micro metal molding is yet to be the field of extensive research...... especially when it is compared with micro molding of thermoplastics. The current paper presents a thorough investigation on the process of metal injection molding where it systematically characterizes the effects of important process conditions on the shrinkage and surface quality of molded parts with micro...

  9. Study on Type C Coal Fly ash as an Additive to Molding Sand for Steel Casting

    Science.gov (United States)

    Palaniappan, Jayanthi

    2016-05-01

    Study of physio-chemical properties studies such as granulometric analysis, moisture, X ray fluorescence etc. were performed with Type C coal—combustion fly ash to investigate their potential as a distinct option for molding sand in foundry, thereby reducing the dependency on latter. Technological properties study such as compressive strength, tensile strength, permeability and compaction of various compositions of fly ash molding sand (10, 20 and 30 % fly ash substitute to chemically bonded sand) were performed and compared with silica molding sand. Steel casting production using this fly ash molding sand was done and the casting surface finish and typical casting parameters were assessed. It was noted that a good quality steel casting could be produced using type C fly ash molding sand, which effectively replaced 20 % of traditional molding sand and binders thereby providing greater financial profits to the foundry and an effective way of fly ash utilization (waste management).

  10. Analysis of Cavity Pressure and Warpage of Polyoxymethylene Thin Walled Injection Molded Parts: Experiments and Simulations

    DEFF Research Database (Denmark)

    Guerrier, Patrick; Tosello, Guido; Hattel, Jesper Henri

    2014-01-01

    Process analysis and simulations on molding experiments of 3D thin shell parts have been conducted. Moldings were carried out with polyoxymethylene (POM). The moldings were performed with cavity pressure sensors in order to compare experimental process results with simulations. The warpage...... was characterized by measuring distances using a tactile coordinate measuring machine (CMM). Molding simulations have been executed taking into account actual processing conditions. Various aspects have been considered in the simulation: machine barrel geometry, injection speed profiles, cavity injection pressure......, melt and mold temperatures, material rheological and pvT characterization. Factors investigated for comparisons were: injection pressure profile, short shots length, flow pattern, and warpage. A reliable molding experimental database was obtained, accurate simulations were conducted and a number...

  11. Improvement of Moldability for Ultra Thin-Wall Molding with Micro-Patterns

    Energy Technology Data Exchange (ETDEWEB)

    Kwon, Oh Kyung; Yun, Jae Ho [Korea Institute of Industrial Technology, Cheonan (Korea, Republic of); Park, Keun [Seoul National Univ. of Technology, Seoul (Korea, Republic of)

    2007-05-15

    The Rapid Thermal Response(RTR) molding is a novel process developed to raise the temperature of mold surface rapidly in the injection stage and then cool rapidly to the ejection temperature by air or water. The objectives of this paper are to investigate the effect of mold temperature, pressure and thickness of micro pattern molding and to provide a optimization of RTR injection molding for micro pattern from Moldflow simulation. Optimal minimum temperature and pressure was found without shortcut according to thickness. Filling percentage was influenced by glass transition temperature with the kinds of resin. Optimal temperature is slightly higher than glass transition temperature irrespectively of pressure, thickness, the kinds of resin in the micro pattern molding.

  12. 40 CFR 160.12 - Statement of compliance or non-compliance.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Statement of compliance or non-compliance. 160.12 Section 160.12 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED... non-compliance. Any person who submits to EPA an application for a research or marketing permit...

  13. Dimensional Accuracy of Stone Casts Obtained with Multiple Pours into the Same Mold

    OpenAIRE

    Valdimar da Silva Valente; Artêmio Luiz Zanetti; Pedro Paulo Feltrin; Ricardo Tatsuo Inoue; Carmem Dolores Vilarinho Soares de Moura; Luiz Evaldo de Moura Pádua

    2012-01-01

    Aim. The aim of the present study was to compare the dimensional accuracy of stone casts obtained with vinyl polysiloxane molds through the double-impression technique with three pours into the same mold. Methods. A stainless steel master model was constructed simulating a three-unit fixed prosthesis. Twelve impressions were taken of this master model with addition silicone, using the double-impression technique. Three pours of type IV gypsum were then made into each mold, thus producing 36 c...

  14. The Neurological Significance of Abnormal Natural Killer Cell Activity in Chronic Toxigenic Mold Exposures

    OpenAIRE

    Ebere Anyanwu; Campbell, Andrew W.; Joseph Jones; Ehiri, John E; Akpan I. Akpan

    2003-01-01

    Toxigenic mold activities produce metabolites that are either broad-spectrum antibiotics or mycotoxins that are cytotoxic. Indoor environmental exposure to these toxigenic molds leads to adverse health conditions with the main outcome measure of frequent neuroimmunologic and behavioral consequences. One of the immune system disorders found in patients presenting with toxigenic mold exposure is an abnormal natural killer cell activity. This paper presents an overview of the neurological signif...

  15. Vacuum Infusion Molding Process Part 1:VIMP Based on a High-Permeable Medium

    Institute of Scientific and Technical Information of China (English)

    ZHU Ying-dan; WANG Ji-hui; YANG Zui; TAN Hua

    2003-01-01

    The visualization experiments were carried out to investigate the permeability of the high-permeable medium (HPM) and the roles of the peel ply and the HPM in the mold filling.The influence of process parameters on mold filling is discussed.Furthermore,the whole vacuum infusion molding process (VIMP) procedure is introduced in detail taking the manufacture of a model boat for example.

  16. Validation of precision powder injection molding process simulations using a spiral test geometry

    DEFF Research Database (Denmark)

    Marhöfer, Maximilian; Müller, Tobias; Tosello, Guido;

    2015-01-01

    Like in many other areas of engineering, process simulations find application in precision injection molding to assist and optimize the quality and design of precise products and the molding process. Injection molding comprises mainly the manufacturing of plastic components. However, the variant ....... The necessary data and the implementation procedure of the new material models are outlined. In order to validate the simulation studies and evaluate their accuracy, the simulation results are compared with experiments performed using a spiral test geometry...

  17. Using multi-objective evolutionary algorithms in the optimization of polymer injection molding

    OpenAIRE

    Fernandes, Célio Bruno Pinto; Pontes, A.J.; Viana, J.C.; Gaspar-Cunha, A.

    2009-01-01

    A Multi-objective optimization methodology has been applied in the optimization of polymer injection molding process. This allowed the optimization of the operating conditions of the process from mold flow simulations, taking into consideration the existence of 5 criteria simultaneously, such as temperature dif-ference on the molding at the end of filling, the maximum pressure, the pressure work, the volumetric shrinkage and the cycle time. The results produced shown that the proposed methodo...

  18. Fabrication of injection molded sintered alpha SiC turbine components

    Science.gov (United States)

    Storm, R. S.; Ohnsorg, R. W.; Frechette, F. J.

    1981-01-01

    Fabrication of a sintered alpha silicon carbide turbine blade by injection molding is described. An extensive process variation matrix was carried out to define the optimum fabrication conditions. Variation of molding parameters had a significant impact on yield. Turbine blades were produced in a reasonable yield which met a rigid quality and dimensional specification. Application of injection molding technology to more complex components such as integral rotors is also described.

  19. Regulation of aggregate size and pattern by adenosine and caffeine in cellular slime molds

    OpenAIRE

    Jaiswal Pundrik; Soldati Thierry; Thewes Sascha; Baskar Ramamurthy

    2012-01-01

    Abstract Background Multicellularity in cellular slime molds is achieved by aggregation of several hundreds to thousands of cells. In the model slime mold Dictyostelium discoideum, adenosine is known to increase the aggregate size and its antagonist caffeine reduces the aggregate size. However, it is not clear if the actions of adenosine and caffeine are evolutionarily conserved among other slime molds known to use structurally unrelated chemoattractants. We have examined how the known factor...

  20. Numerical modeling of magnetic induction and heating in injection molding tools

    DEFF Research Database (Denmark)

    Guerrier, Patrick; Hattel, Jesper Henri

    2013-01-01

    Injection molding of parts with special requirements or features such as micro- or nanostructures on the surface, a good surface finish, or long and thin features results in the need of a specialized technique to ensure proper filling and acceptable cycle time. The aim of this study is to increase...... numerical modeling of the induction heating in the mold to investigate how the temperature in the mold will be distributed and how it is affected by different material properties....

  1. Preparation of liquefied wood-based resins and their application in molding material

    Institute of Scientific and Technical Information of China (English)

    Zhang Qiu-hui; Zhao Guang-jie; Yu Li-li; Jie Shu-jun

    2007-01-01

    To investigate value in use of liquefied wood-based resin applications in molding material, Chinese fir (Cunninghamia lanceolata) and poplar (Populus tomentosa) wood meal were liquefied in phenol. The reactant was co-condensed with formaldehyde to obtain liquefied wood-based resin. For this paper, we investigated the characterization of the resin and its application in molding material. The result shows that the basic properties of liquefied wood-based resin were satisfactory; the bonding strength of plywood prepared with liquefied Chinese fir and liquefied poplar resin can reach 1.54 and 1.00 MPa, respectively. The compression strengths of the molding material prepared with two kinds of liquefied wood resin were 73.01 and 73.58 MPa, almost the same as that of PF resin molding material. The limiting volume swelling of molding material made with liquefied Chinese resin and liquefied poplar resin were 8.5% and 8.3%, thickness swelling rates of water absorption were 3.3% and 4.2%, and the maximum weight ratios of water absorption were 25.9% and 26.2%, respectively. The soil burial test result shows that the weight loss rate of the molding materials made with liquefied Chinese resin and liquefied poplar resin were 8.3% and 9.1% and that of the PF resin molding material was 7.9%. After the soil internment test, the reduction ratio of compression strength of the two kinds of molding material achieved 16.9%and 17.7%, while that of the PF resin molding material was 15.4%. The test results of wood fungi inoculation on the three surfaces of the molding material indicate the breeding rate of molding material prepared with liquefied Chinese resin and liquefied poplar resin were at level 4 and that of PF resin molding material was at level 1 of the ISO standard.

  2. Facile preparation of agarose-chitosan hybrid materials and nanocomposite ionogels using an ionic liquid via dissolution, regeneration and sol-gel transition

    CERN Document Server

    Trivedi, Tushar J; Kumar, Arvind

    2014-01-01

    We report simultaneous dissolution of agarose (AG) and chitosan (CH) in varying proportions in an ionic liquid (IL), 1-butyl-3-methylimidazolium chloride [C4mim][Cl]. Composite materials were constructed from AG-CH-IL solutions using the antisolvent methanol, and IL was recovered from the solutions. Composite materials could be uniformly decorated with silver oxide (Ag2O) nanoparticles (Ag NPs) to form nanocomposites in a single step by in situ synthesis of Ag NPs in AG-CH-IL sols, wherein the biopolymer moiety acted as both reducing and stabilizing agent. Cooling of Ag NPs-AG-CH-IL sols to room temperature resulted in high conductivity and high mechanical strength nanocomposite ionogels. The structure, stability and physiochemical properties of composite materials and nanocomposites were characterized by several analytical techniques, such as Fourier transform infrared (FTIR), CD spectroscopy, differential scanning colorimetric (DSC), thermogravimetric analysis (TGA), gel permeation chromatography (GPC), and...

  3. Analysis of branched DNA replication and recombination intermediates from prokaryotic cells by two-dimensional (2D) native-native agarose gel electrophoresis.

    Science.gov (United States)

    Robinson, Nicholas P

    2013-01-01

    Branched DNA molecules are generated by the essential processes of replication and recombination. Owing to their distinctive extended shapes, these intermediates migrate differently from linear double-stranded DNA under certain electrophoretic conditions. However, these branched species exist in the cell at much low abundance than the bulk linear DNA. Consequently, branched molecules cannot be visualized by conventional electrophoresis and ethidium bromide staining. Two-dimensional native-native agarose electrophoresis has therefore been developed as a method to facilitate the separation and visualization of branched replication and recombination intermediates. A wide variety of studies have employed this technique to examine branched molecules in eukaryotic, archaeal, and bacterial cells, providing valuable insights into how DNA is duplicated and repaired in all three domains of life.

  4. Carboxylated Agarose (CA)-Silk Fibroin (SF) Dual Confluent Matrices Containing Oriented Hydroxyapatite (HA) Crystals: Biomimetic Organic/Inorganic Composites for Tibia Repair.

    Science.gov (United States)

    Hu, Jing-Xiao; Ran, Jia-Bing; Chen, Si; Jiang, Pei; Shen, Xin-Yu; Tong, Hua

    2016-07-11

    By in situ combining the dual cross-linking matrices of the carboxylated agarose (CA) and the silk fibroin (SF) with the hydroxyapatite (HA) crystals, the CA-SF/HA composites with optimal physicochemical and biological properties were obtained, which were designed to meet the clinical needs of load-bearing bone repair. With the synergistic modulation of the dual organic matrices, the HA nanoparticles presented sheet and rod morphologies due to the preferred orientation, which successfully simulated the biomineralization in nature. The chemical reactivity of the native agarose (NA) was significantly enhanced via carboxylation, and the CA exhibited higher thermal stability than the NA. In the presence of SF, the composites showed optimal mechanical properties that could meet the standard of bone repair. The degradation of the composites in the presence of CA and SF was significantly delayed such that the degradation rate of the implant could satisfy the growth rate of the newly formed bone tissue. The in vitro tests confirmed that the CA-SF/HA composite scaffolds enabled the MG63 cells to proliferate and differentiate well, and the CA/HA composite presented greater capability of promoting the cell behaviors than the NA/HA composite. After 24 days of implantation, newly formed bone was observed at the tibia defect site and around the implant. Extensive osteogenesis was presented in the rats treated with the CA-SF/HA composites. In general, the CA-SF/HA composites prepared in this work had the great potential to be applied for repairing large bone defects.

  5. Gate design in injection molding of microfluidic components using process simulations

    DEFF Research Database (Denmark)

    Marhöfer, D. M.; Tosello, G.; Islam, A.;

    2015-01-01

    Just as in conventional injection molding of plastics, process simulations are an effective tool in the area of micro injection molding. They are applied in order to optimize and aid the design of the micro plastic part, the mold and the actual process. Available simulation software is actually...... made for macroscopic injection molding, but by means of the correct implementation and modelling strategy it can also be applied to micro plastic parts, as it is shown in the presented work. Process simulations are applied to two microfluidic devices (a micro distributor and a micro mixer) which shall...

  6. Wireless accelerometer network for process monitoring during mold forming in lost foam casting

    Science.gov (United States)

    Whelan, Matthew J.; Janoyan, Kerop D.

    2006-03-01

    Lost Foam Casting (LFC) enables the production of complex castings while offering the advantages of consolidation of components, reduced machining, and recirculation of the casting mold material. In the process, a replica of the desired product is produced of blown polystyrene, coated in refractory slurry, and cast in a dense, unbonded sand mold. In order for the unbonded sand mold to fill into pattern holes and to provide sufficient confining force to prevent the advancing molten front from penetrating beyond the mold boundaries, the sand mold is produced by an overhead raining and flask vibration schedule that encourages fluidization and subsequent densification. The amplitude, frequency, and duration of the flask vibration as well as the rate of sand filling are critical parameters in achieving quality castings. Currently, many foundries use an often-lengthy trial-and-error process for determining an acceptable raining and vibration schedule for each specific mold and rely heavily on simple measurements and operator experience to control the mold making process on the foundry line. This study focuses on developing a wireless sensor network of accelerometers to monitor vibrational characteristics of the casting flask during the mold making stage of LFC. Transformations in the vibrational characteristics of the flask can provide a "signature" for indicating the condition of the unbonded sand mold. Additionally, the wireless nature of the sensor nodes enables the technology to travel across the foundry floor during the casting cycle eliminating the necessity of routine placement and setup.

  7. Experimental Investigation of Comparative Process Capabilities of Metal and Ceramic Injection Molding for Precision Applications

    DEFF Research Database (Denmark)

    Islam, Aminul; Giannekas, Nikolaos; Marhöfer, David Maximilian;

    2016-01-01

    The purpose of this paper is to make a comparative study on the process capabilities of the two branches of the powder injection molding (PIM) process—metal injection molding (MIM) and ceramic injection molding (CIM), for high-end precision applications. The state-of-the-art literature does not m...... and discussion presented in the paper will be useful for thorough understanding of the MIM and CIM processes and to select the right material and process for the right application or even to combine metal and ceramic materials by molding to produce metal–ceramic hybrid components....

  8. Injection molded polymer chip for electrochemical and electrophysiological recordings from single cells

    DEFF Research Database (Denmark)

    Tanzi, Simone; Larsen, Simon Tylsgaard; Taboryski, Rafael J.

    We present a novel method to fabricate an all in polymer injection molded chip for electrochemical cell recordings and lateral cell trapping. The complete device is molded in thermoplastic polymer and it results from assembling two halves. We tested spin-coated conductive polymer poly(3,4-ethylen......We present a novel method to fabricate an all in polymer injection molded chip for electrochemical cell recordings and lateral cell trapping. The complete device is molded in thermoplastic polymer and it results from assembling two halves. We tested spin-coated conductive polymer poly(3...

  9. Micro powder injection molding-large scale production technology for micro-sized components

    Institute of Scientific and Technical Information of China (English)

    YIN HaiQing; JIA ChengChang; QU XuanHui

    2008-01-01

    Micro powder injection molding (μPIM), a miniaturized variant of powder injection molding, has advantages of shape complexity, applicability to many materials and good mechanical properties. Co-injection molding has been realized between metals and ceramics on micro components, which become the first breakthrough within the PIM field. Combined with the prominent characteristics of high features/cost ratio, micro powder injection molding becomes a potential technique for large scale production of intricate and three-dimensional micro components or microstructured components in microsystems technology (MST) field.

  10. Investigation of the adhesion interface obtained through two-component injection molding

    Science.gov (United States)

    Fetecau, Catalin; Stan, Felicia; Dobrea, Daniel

    2011-01-01

    In this paper we study the interface strength obtained through two-component (2C) injection molding of LDPE-HDPE polymers. First, numerical simulation of the over-molding process is carried out using Moldflow technology. Second, butt-joint specimens were produced by over-molding under different process condition, and tested. Two injection sequences were considered, injection of LDPE on HDPE polymer, and HDLE on LDPE, respectively. To investigate the effects of the mold surface roughness on the polymers adhesion at interface, different inserts with different roughness are employed.

  11. The Relationship between Mold Exposure and Allergic Response in Post-Katrina New Orleans

    Directory of Open Access Journals (Sweden)

    Felicia A. Rabito

    2010-01-01

    Full Text Available Objectives. The study's objective was to examine the relation between mold/dampness exposure and mold sensitization among residents of Greater New Orleans following Hurricane Katrina. Methods. Patients were recruited from the Allergy Clinic of a major medical facility. Any patient receiving a skin prick test for one of 24 molds between December 1, 2005 and December 31, 2008 was eligible for the study. Exposure was assessed using standardized questionnaires. Positive mold reactivity was defined as a wheal diameter >3 mm to any mold genera. Results. Approximately 57% of participants tested positive to any indoor allergen, 10% to any mold. Over half of respondents had significant home damage, 34% reported dampness/mold in their home, half engaged in renovation, and one-third lived in a home undergoing renovation. Despite extensive exposure, and multiple measures of exposure, we found no relationship between mold/dampness exposure and sensitivity to mold allergens. Conclusions. These results along with results of earlier research indicate no excess risk of adverse respiratory effects for residents living in New Orleans after the devastation of Hurricane Katrina.

  12. Environmental Compliance Audit& Assessment Program Manual

    Energy Technology Data Exchange (ETDEWEB)

    Thorson, Patrick; Baskin, David; Borglin, Ned; Fox, Robert; Wahl, Linnea; Hatayama, Howard; Pauer, Ronald

    2009-03-13

    This document describes the elements, schedule, roles, and responsibilities of the Lawrence Berkeley National Laboratory (LBNL) Environmental Compliance Audit & Assessment Program (ECAAP). The ECAAP has been developed to meet the requirements of DOE Order 450.1A,1 and Executive Order 13423.2 These referenced Orders stipulate that government agencies must develop environmental compliance audit programs to monitor and improve compliance with environmental regulations. As stated specifically in the DOE Order, as a part of a DOE facility's Environmental Management System (EMS), 'An environmental compliance audit and review program that identifies compliance deficiencies and root causes of non-compliance' shall be developed and implemented. The ECAAP has also been developed to satisfy LBNL's institutional technical assurance assessment requirements promulgated in the Environment, Safety and Health (ES&H) Self-Assessment Program (LBNL/PUB-5344) and described by the ES&H Technical Assurance Program (TAP) Manual (LBNL/PUB-913E). The ES&H TAP Manual provides the framework for systematic reviews of ES&H programs with the intent to provide assurance that these programs comply with their guiding regulations, are effective, and are properly implemented. As required by the DOE and Executive Orders and by LBNL's TAP, the goal of the ECAAP is to identify environmental regulatory compliance deficiencies and to determine their respective causes. The ECAAP then provides a means of correcting any deficiencies identified, and leads to continually improving environmental compliance performance.

  13. Patient compliance and effect of orthopaedic shoes

    DEFF Research Database (Denmark)

    Philipsen, A B; Ellitsgaard, N; Krogsgaard, M R;

    1999-01-01

    Orthopaedic shoes are individually handmade after a prescription from an orthopaedic surgeon, hence relatively expensive. Bad compliance is mentioned in the literature but not investigated. In order to evaluate patient compliance and the effect of orthopaedic shoes, 85 patients who were prescribe...

  14. 45 CFR 80.6 - Compliance information.

    Science.gov (United States)

    2010-10-01

    ... 45 Public Welfare 1 2010-10-01 2010-10-01 false Compliance information. 80.6 Section 80.6 Public... THE CIVIL RIGHTS ACT OF 1964 § 80.6 Compliance information. (a) Cooperation and assistance. The... reports at such times, and in such form and containing such information, as the responsible...

  15. 44 CFR 7.10 - Compliance information.

    Science.gov (United States)

    2010-10-01

    ... 44 Emergency Management and Assistance 1 2010-10-01 2010-10-01 false Compliance information. 7.10... in FEMA-Assisted Programs-General § 7.10 Compliance information. (a) Cooperation and assistance. The... such information, as the responsible agency official or his designee may determine to be necessary...

  16. 40 CFR 61.173 - Compliance provisions.

    Science.gov (United States)

    2010-07-01

    ...) NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS National Emission Standard for Inorganic Arsenic Emissions From Primary Copper Smelters § 61.173 Compliance provisions. (a) The owner or operator of each copper converter to which § 61.172(b)-(f) applies shall demonstrate compliance with the requirements...

  17. 45 CFR 50.8 - Compliance.

    Science.gov (United States)

    2010-10-01

    ... 45 Public Welfare 1 2010-10-01 2010-10-01 false Compliance. 50.8 Section 50.8 Public Welfare DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL ADMINISTRATION U.S. EXCHANGE VISITOR PROGRAM-REQUEST FOR WAIVER OF THE TWO-YEAR FOREIGN RESIDENCE REQUIREMENT § 50.8 Compliance. If an alien physician acquires...

  18. 40 CFR 52.1335 - Compliance schedules.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 4 2010-07-01 2010-07-01 false Compliance schedules. 52.1335 Section 52.1335 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED... Effective date Final compliance date Pilot Knob Pelleting Co Pilot Knob, MO V(10 CSR 10-3.050) Oct. 19,...

  19. Determinants of Compliance among Pediatric Amblyopia Patients.

    Science.gov (United States)

    Wolff, Hans; Juhasz, Anne McCreary

    Given the recent focus on patient responsibility for health status and improvement, it is important to understand the dynamics involved in patient compliance to treatment regimens. The determinants of patching compliance among 30 pediatric amblyopia patients and their parents were investigated by means of parent, patient, and physician…

  20. Monitoring managers through corporate compliance programs

    NARCIS (Netherlands)

    C. Angelucci; M.A. Han

    2011-01-01

    Compliance programs entail monitoring of employees' behavior with the claimed objective of fighting corporate crime. (Competition) Authorities promote such intra-firm monitoring. In a three-tier hierarchy model, authority-shareholder-manager, we study the impact of monitoring through a compliance pr