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Sample records for hashish body packing

  1. Radiological and practical aspects of body packing.

    PubMed

    Pinto, A; Reginelli, A; Pinto, F; Sica, G; Scaglione, M; Berger, F H; Romano, L; Brunese, L

    2014-04-01

    Body packing represents the concealment of illegal substances in a person's body with the aim of smuggling. "Body packers" either swallow drug-filled packets or introduce drug-filled packets into their bodies rectally or vaginally with the purpose of concealing them. The three main smuggled drugs are cocaine, heroin and cannabis products. Body packing represents a serious risk of acute narcotic toxicity from drug exposure, intestinal obstruction owing to pellet impaction and bowel perforation with consequent abdominal sepsis. A suspected body packer is generally admitted to hospital to perform imaging investigations and confirm the presence of drugs in his/her body. Radiological imaging methods are essential to diagnose body packing and to detect potential complications. Increasing sophistication of traffickers and improvements in packaging add to the detection difficulty. Radiologists should be aware of the appearance of drug packets in a range of imaging modalities. This article informs physicians about the challenging aspects of body packing, its background and medicolegal issues, what imaging methods can be used and what criteria are necessary to perform a correct diagnosis. PMID:24472727

  2. Radiological and practical aspects of body packing

    PubMed Central

    Reginelli, A; Pinto, F; Sica, G; Scaglione, M; Berger, F H; Romano, L; Brunese, L

    2014-01-01

    Body packing represents the concealment of illegal substances in a person's body with the aim of smuggling. “Body packers” either swallow drug-filled packets or introduce drug-filled packets into their bodies rectally or vaginally with the purpose of concealing them. The three main smuggled drugs are cocaine, heroin and cannabis products. Body packing represents a serious risk of acute narcotic toxicity from drug exposure, intestinal obstruction owing to pellet impaction and bowel perforation with consequent abdominal sepsis. A suspected body packer is generally admitted to hospital to perform imaging investigations and confirm the presence of drugs in his/her body. Radiological imaging methods are essential to diagnose body packing and to detect potential complications. Increasing sophistication of traffickers and improvements in packaging add to the detection difficulty. Radiologists should be aware of the appearance of drug packets in a range of imaging modalities. This article informs physicians about the challenging aspects of body packing, its background and medicolegal issues, what imaging methods can be used and what criteria are necessary to perform a correct diagnosis. PMID:24472727

  3. Imaging of drug smuggling by body packing.

    PubMed

    Sica, Giacomo; Guida, Franco; Bocchini, Giorgio; Iaselli, Francesco; Iadevito, Isabella; Scaglione, Mariano

    2015-02-01

    Body packing, pushing, and stuffing are hazardous practices with complex medicolegal and social implications. A radiologist plays both a social and a medicolegal role in their assessment, and it should not be limited only to the identification of the packages but must also provide accurate information about their number and their exact location so as to prevent any package remains in the body packer. Radiologists must also be able to recognize the complications associated with these risky practices. Imaging assessment of body packing is performed essentially through plain abdominal X-ray and computed tomography scans. Ultrasound and magnetic resonance imaging, although with some advantages, actually have a limited use. PMID:25639176

  4. Body packing: from seizures to laparotomy.

    PubMed

    Janczak, Joanna M; Beutner, Ulrich; Hasler, Karin

    2015-01-01

    Body packing is a common method for illegal drug trafficking. Complications associated with body packing can be severe and even lead to rapid death. Thus, a timely diagnosis is warranted. As most body packers initially do not show any symptoms, making a correct diagnosis can be rather challenging. We describe a case of a 41-year-old male, who was admitted with an epileptic seizure and who turned out to be a cocaine intoxicated body packer. Due to neurological and cardiovascular deterioration an emergency surgery was performed. Four bags of cocaine could be removed. We discuss the current management regimen in symptomatic and asymptomatic body packers and highlight pearls and pitfalls with diagnosis and treatment. PMID:25883813

  5. Body Packing: From Seizures to Laparotomy

    PubMed Central

    Janczak, Joanna M.; Beutner, Ulrich; Hasler, Karin

    2015-01-01

    Body packing is a common method for illegal drug trafficking. Complications associated with body packing can be severe and even lead to rapid death. Thus, a timely diagnosis is warranted. As most body packers initially do not show any symptoms, making a correct diagnosis can be rather challenging. We describe a case of a 41-year-old male, who was admitted with an epileptic seizure and who turned out to be a cocaine intoxicated body packer. Due to neurological and cardiovascular deterioration an emergency surgery was performed. Four bags of cocaine could be removed. We discuss the current management regimen in symptomatic and asymptomatic body packers and highlight pearls and pitfalls with diagnosis and treatment. PMID:25883813

  6. Heroin body packing: three fatal cases of intestinal perforation.

    PubMed

    Hutchins, K D; Pierre-Louis, P J; Zaretski, L; Williams, A W; Lin, R L; Natarajan, G A

    2000-01-01

    Death from heroin body packing has been well described in the forensic literature. Most fatalities are due to drug leakage and consequent acute heroin toxicity. Recently, drug traffickers have become more sophisticated in their packaging, and the risk of rupture of drug packets is more remote. Though intestinal obstruction is a recognized risk of body packing, rarely has this resulted in death. We describe four cases of heroin body packing presenting to the Regional Medical Examiner Office in New Jersey. Death in three of these cases was due to intestinal obstruction, with resultant intestinal rupture and peritonitis. Toxicologic evaluation in these three cases was negative for opiates or other drugs of abuse. In one case, death was due to acute heroin toxicity, validated by toxicologic analysis. We briefly discuss the differing drug packaging found in these four cases and the ramifications of packaging as it relates to intestinal obstruction. PMID:10641918

  7. Imaging of body packing: errors and medico-legal issues.

    PubMed

    Reginelli, Alfonso; Russo, Anna; Urraro, Fabrizio; Maresca, Duilia; Martiniello, Ciro; D'Andrea, Alfredo; Brunese, Luca; Pinto, Antonio

    2015-10-01

    Body packing is the ingestion or insertion in the human body of packed illicit substances. Over the last 20 years, drug smuggling has increased global and new means of transport of narcotics have emerged. Among these, the most frequent one is the gastrointestinal tract: from mouth to anus, vagina, and ears. Cocaine is one of the most traded drugs, followed by heroin. Condoms, latex gloves, and balloons are typically used as drug packets for retention in the body. There are different radiologic modalities to detect illicit drugs in body packing: Plain radiography, computed tomography (CT), ultrasound, and magnetic resonance. Current protocols recommend the use of radiography to confirm packet retention and, in case of doubt, the use of abdominal CT scan with reduced mAs. In case of packet rupture, catastrophic effects can occur. Management of patients carrying packets of drugs is a recurrent medico-legal problem. To improve diagnostic accuracy and prevent hazardous complications, radiologists and emergency physicians should be familiar with radiologic features of body packing. The radiologist plays both a social and a medico-legal role in their assessment, and it should not be limited only to the identification of the packages but must also provide accurate information about their number and their exact location. In this review, we focus on diagnostic errors and medico-legal issues related to the radiological assessment of body packers. PMID:26063072

  8. [Clinical and electroencephalographic observations during the acute action of hashish (author's transl)].

    PubMed

    Seyfeddinipur, N

    1975-03-21

    The physical and mental reactions were registered before and after smoking 2 g hashish in 30 volunteers who had never smoked hashish before. The EEG shows no pathological changes. Hashish significantly raises the heart rate. The blood pressure shows a tendency to fall. The cardiovascular disturbances may be so marked that collapse occurs. The reaction of fear after acute hashish intoxication may lead to unpleasant defense reactions. Hashish implies a danger to road traffic because of the physical ataxia and alterations in appreciation of time and space. PMID:805910

  9. Body packing and its radiologic manifestations: a review article.

    PubMed

    Shahnazi, Makhtoom; Sanei Taheri, Morteza; Pourghorban, Ramin

    2011-12-01

    Body packing is described as using the abdominal or pelvic cavity for concealing illegal drugs. Leakage from the packets may cause catastrophic effects on smugglers and medical history is not reliable in these patients. Moreover, new sophisticated smuggling techniques make it imperative that radiologists and emergency physicians understand and familiarize themselves with the different radiological manifestations of ingested drug packets. Currently, there is no gold standard for imaging patients suspected of body packing; nevertheless, computed tomography (CT) seems to be the best modality for packet detection and unenhanced CT without bowel preparation is a reliable technique for detection of ingested packets. On abdominal radiography, packets may be visualized as oval or round radiopaque foreign bodies surrounded by a gas halo. In the literature, sensitivity of abdominal radiography is reported from 74% to 100%. Visualization of the drug packets may be strikingly hampered by administration of oral or intravenous contrast medium in abdomino-pelvic CT; hence, contrast-enhanced CT does not seem to be a suitable modality for searching the ingested packets in suspicious smugglers. PMID:23329942

  10. Window manipulation in diagnosis of body packing using computed tomography.

    PubMed

    Sengupta, Anshuman; Page, Patrick

    2008-05-01

    Body packing refers to the internal concealment of narcotics, usually within the gastrointestinal tract. This is important to recognise for clinical and forensic reasons. Imaging is often helpful, particularly because an accurate history is unusual. Furthermore, clinical examination and urine screens are often unreliable. Plain abdominal radiography and ultrasonography have been used with limited success. Thus, the use of alternative modalities, such as computed tomography (CT), is becoming more widespread. Although there have been no large trials, one false-negative has been reported. We report the case of a body packer whose CT appeared normal with standard abdominal windowing (level 40/width 400). However, on manipulation of the windowing (level -175/width 600), paraffin and heroin packages became conspicuous within the colon. We suggest that the simple step of reviewing images on wider than standard abdominal windows may be helpful in the detection of ingested illicit packages of fatty density within the bowel. PMID:17713799

  11. Cannabinoids in hair: strategy to prove marijuana/hashish consumption.

    PubMed

    Uhl, Michael; Sachs, Hans

    2004-10-29

    Delta9-Tetrahydrocannabinol (THC) and 11-nor-Delta9-tetrahydrocannabinol-9-carboxylic acid (THCA) are equally used to indicate consumption of cannabis (hashish and marijuana). Publications of the early 90's demonstrate the possibilities of determining THC, cannabinol (CBN), and cannabidiol (CBD). All these substances are present in cannabis smoke and can be incorporated into the hair only by contamination. Generally, washing procedures should prevent false positive results, but finally it cannot be excluded that traces of THC may be found in hair after mere passive cannabis smoke exposure. Three authentic cases illustrate the problems originating in the exclusive determination of THC/CBN. The first example is the case of a couple living together in an apartment. Both persons' hair samples had been taken and gave positive results for THC and CBN. The male subject admitted smoking cannabis several times per day, but the female mate denied any consumption. Examination of the hair for THCA showed a high level (>6.6 pg/mg) in the sample of the male person and negative results (LOQ 0.1 pg/mg) in the sample of his mate. The second case hair is of a self admitted cannabis user's hair and was tested first by an immunoassay and GC/MS with a negative result. Nevertheless, the THCA concentration quantified in his sample was 2.7 pg/mg hair. The third hair sample is of a 2-year-old child that was tested positive for cannabis by using an immunochemical test. No THC and CBN were detectable by GC/MS, however, trace amounts of THCA using GC/MS/MS. A comparative study of hair samples (screening for cannabinoids using ELISA test, THC determination by GC/MS, THCA by GC/MS/MS) showed that only 26 segments of 66 were positive for both THC and THCA. Thirteen were negative for THC and positive for THCA, and six were positive for THC but negative for THCA. The cases were selected by an ELISA test or re-examined when the blood/urine results or the statement of the accused did not match with

  12. Systematic review of the toxicological and radiological features of body packing.

    PubMed

    Cappelletti, Simone; Piacentino, Daria; Sani, Gabriele; Bottoni, Edoardo; Fiore, Paola Antonella; Aromatario, Mariarosaria; Ciallella, Costantino

    2016-05-01

    Body packing is the term used for the intracorporeal concealment of illicit drugs, mainly cocaine, heroin, methamphetamine, and cannabinoids. These drugs are produced in the form of packages and are swallowed or placed in various anatomical cavities and body orifices. Basing on these two ways of transportation a distinction between body stuffers and body pushers can be made, with the former described as drug users or street dealers who usually carry small amounts of drugs and the latter as professional drug couriers who carry greater amounts of drugs. A review of the literature regarding body packing is presented, with the aim to highlight the toxicological and radiological features related to this illegal practice. Raising awareness about the encountered mean body levels of the drugs and the typical imaging signs of the incorporated packages could be useful for clinicians and forensic pathologists to (a) identify possible unrecognized cases of body packing and (b) prevent the serious health consequences and deaths frequently occurring after the packages' leakage or rupture or the packages' mass obstructing the gastrointestinal lumen. PMID:26932867

  13. [Intraindividual comparison of whole body cold therapy and warm treatment with hot packs in generalized tendomyopathy].

    PubMed

    Samborski, W; Stratz, T; Sobieska, M; Mennet, P; Müller, W; Schulte-Mönting, J

    1992-01-01

    In a cross-over study, the short-term efficacy of whole-body cold therapy and hot mud packs in patients with generalized tendomyopathy (fibromyalgia) was compared. As a pain assessment, visual analog scale and so-called pain score were measured; dolorimetry of the 24 tender points and eight control points was performed as well. Using these methods, we found that there is a significant improvement of all parameters examined during a 2-h period of measurements after cold application, and a marked improvement was also detectable 24 h after this therapy. In contrast, only pain score values showed a slight decrease immediately after hot mud-pack therapy, and no significant differences were found in visual analog scale and pressure tenderness as measured dolorimetrically. Central inhibition of nociceptors as a result of an activation of A-delta system as well as a blockade of gamma-motoneurons are discussed to be a mechanism of action of whole-body cold therapy, resulting in a decrease in muscle tonus. Long-term studies are needed to determine, if there is any enduring effect of whole-body cold therapy on pain in the patients with generalized tendomyopathy. PMID:1574933

  14. Prevalence and Correlates of Hashish Use in a National Sample of High School Seniors in the United States

    PubMed Central

    Palamar, Joseph J.; Lee, Lily; Weitzman, Michael

    2015-01-01

    Background Cannabis (marijuana) use and acceptance towards use are increasing in the US, and state-level policies are becoming more liberal. A wealth of research has been conducted to examine risk factors for use; however, studies rarely differentiate between different forms of marijuana. Objective We sought to determine prevalence of use and delineate who is at risk for use of this more potent form of marijuana. Methods We examined data from a nationally representative sample of high school seniors in the Monitoring the Future study (2007–2011; weighted N=10,597). We determined how sociodemographic factors and reasons for marijuana use correlated with recent (12-month) hashish use. Results Prevalence of recent hashish use was 6.5% and it was used by 18.3% of recent marijuana users. Hashish and other marijuana use tended to share many of the same correlates; however, associations were often stronger for hashish use. Females were consistently at low risk for use and users of other drugs were consistently at high risk for use. Black students tended to be at low risk for hashish use. Low risk of identifying as Hispanic or religious and high risk of higher personal income or going out more evenings per week for fun disappeared when controlling for other drug use. Using marijuana because the student felt he/she was “hooked” nearly doubled the odds for hashish use. Conclusions This was the first national study to examine prevalence and correlates of hashish use. These findings can inform prevention in a time of increasing popularity of marijuana use. PMID:25860964

  15. Body packing: a review of general background, clinical and imaging aspects.

    PubMed

    Berger, Ferco H; Nieboer, Koenraad H; Goh, Gerard S; Pinto, Antonio; Scaglione, Mariano

    2015-01-01

    To avoid detection at border crossings or airport customs, drug trafficking is increasingly performed by intra-corporeal concealment. Body packers may ingest packets of varying size and containing varying drugs (mostly cocaine, heroin and cannabis) mixed with other compounds, while body pushers will insert packets in the rectum or vaginal cavity. Body packing may lead to potential life-threatening complications with acute overdose syndromes after packet rupture and intestinal obstruction with possible ensuing bowel rupture being the most significant complications. Physicians including radiologists should be aware of the capabilities of imaging techniques to screen for presence of drug packets as well as the potential complications. Although conventional radiography has long been and still is the most important imaging modality for screening for presence of intestinal packets, the better test characteristics in conjunction with the decreasing radiation exposure, will likely render computed tomography (CT) more important in the future. For imaging of symptomatic patients, CT already is the modality of choice. Besides these modalities, ultrasound and magnetic resonance imaging will be discussed in this paper, together with more general background and clinical information. PMID:25300715

  16. Drug-related deaths with evidences of body packing: Two case reports and medico-legal issues.

    PubMed

    Cappelletti, Simone; Aromatario, Mariarosaria; Bottoni, Edoardo; Fiore, Paola Antonella; Straccamore, Marco; Umani Ronchi, Federica; De Mari, Guido Maria; Ciallella, Costantino

    2016-05-01

    Body packing is a general term used to indicate the internal transportation of drug packages, mainly cocaine, heroin, amphetamines, and methamphetamine, within the gastrointestinal tract. We described two cases of accidental drug intoxication, observed over the last year period, with evidence of intracorporeal drug concealment. The first case concerned a body packer transporting 69 drug packages of heroin adulterated with piracetam. The second body packer transported 16 drug packages of cocaine adulterated with levamisole. For both cases, forensic examination and toxicological analysis of drug packages and biological samples were carried out. Authors also wants to highlight the main medico-legal issues that commonly arise in cases of suspected or ascertained body packers. PMID:27161917

  17. The Symmetry and Packing Fraction of the Body Centered Tetragonal Structure

    ERIC Educational Resources Information Center

    Dunlap, Richard A.

    2012-01-01

    It is shown that for different ratios of lattice parameters, "c/a," the body centered tetragonal structure may be view as body centered tetragonal, body centered cubic, face centered cubic or hexagonal. This illustrates that the apparent symmetry of a lattice depends on the choice of the conventional unit cell.

  18. Genetic parameters for faecal egg count, packed-cell volume and body-weight in Santa Inês lambs

    PubMed Central

    2009-01-01

    Worm infection is one of the main factors responsible for economic losses in sheep breeding in Brazil. Random regression analysis was used to estimate genetic parameters for the factors faecal egg-count (FEC), packed-cell volume (PCV) and body weight (BW) in Santa Inês lambs. Data from 119 female, offspring of nine rams, were collected between December, 2005 and December, 2006, from the experimental flock of Embrapa Tabuleiros Costeiros, the Brazilian Agricultural Research Corporation located in Frei Paulo, SE, Brazil. After weaning, females were drenched until the faecal egg count had dropped to zero. Two natural challenges were undertaken. FEC heritability was extremely variable, this increasing from 0.04 to 0.27 in the first challenge and from 0.01 to 0.52 during the second. PCV heritability peaks were 0.31 and 0.12 in the first and second challenges, respectively. In the second challenge, BW heritability was close to 0.90. The genetic correlations among these traits did not differ from zero. There is the possibility of increasing parasite resistance in Santa Inês by selecting those animals with lower FEC. Selection to increase resistance will not adversely affect lamb-growth, although lambs with a slow growth-rate may be more susceptible to infection. PMID:21637682

  19. [Testing the identity of hashish samples with ICP-AES and NAA and data handling with neural networks. 2. Data verification with the use of artificial neural networks].

    PubMed

    Tenhagen, A; Feuring, T; Lippe, W M

    1998-01-01

    Twenty different hashish samples, which were confiscated in Irak, Iran, Bulgaria, Switzerland, Great Britain and Germany were analysed by means of NAA and ICP-AES. We used modified ANNs to identify a repeated analysed sample out of that data pool. The ANNs are described. Especially the learning rule, a modified backpropagation method, is presented. It is obvious, that neural networks can solve the described classification tasks. There is no significant difference in the power of the applied analytical methods. PMID:9476257

  20. Nasal packing and stenting

    PubMed Central

    Weber, Rainer K.

    2011-01-01

    Nasal packs are indispensable in ENT practice. This study reviews current indications, effectiveness and risks of nasal packs and stents. In endoscopic surgery, nasal packs should always have smooth surfaces to minimize mucosal damage, improve wound healing and increase patient comfort. Functional endoscopic endonasal sinus surgery allows the use of modern nasal packs, since pressure is no longer required. So called hemostatic/resorbable materials are a first step in this direction. However, they may lead to adhesions and foreign body reactions in mucosal membranes. Simple occlusion is an effective method for creating a moist milieu for improved wound healing and avoiding dryness. Stenting of the frontal sinus is recommended if surgery fails to produce a wide, physiologically shaped drainage path that is sufficiently covered by intact tissue. PMID:22073095

  1. Battery pack

    SciTech Connect

    Weaver, R.J.; Brittingham, D.C.; Basta, J.C.

    1993-07-06

    A battery pack is described, having a center of mass, for use with a medical instrument including a latch, an ejector, and an electrical connector, the battery pack comprising: energy storage means for storing electrical energy; latch engagement means, physically coupled to the energy storage means, for engaging the latch; ejector engagement means, physically coupled to the energy storage means, for engaging the ejector; and connector engagement means, physically coupled to the energy storage means, for engaging the connector, the latch engagement means, ejector engagement means, and connector engagement means being substantially aligned in a plane offset from the center of mass of the battery pack.

  2. Dense periodic packings of tori

    NASA Astrophysics Data System (ADS)

    Gabbrielli, Ruggero; Jiao, Yang; Torquato, Salvatore

    2014-02-01

    Dense packings of nonoverlapping bodies in three-dimensional Euclidean space R3 are useful models of the structure of a variety of many-particle systems that arise in the physical and biological sciences. Here we investigate the packing behavior of congruent ring tori in R3, which are multiply connected nonconvex bodies of genus 1, as well as horn and spindle tori. Specifically, we analytically construct a family of dense periodic packings of unlinked tori guided by the organizing principles originally devised for simply connected solid bodies [22 Torquato and Jiao, Phys. Rev. E 86, 011102 (2012), 10.1103/PhysRevE.86.011102]. We find that the horn tori as well as certain spindle and ring tori can achieve a packing density not only higher than that of spheres (i.e., π /√18 =0.7404...) but also higher than the densest known ellipsoid packings (i.e., 0.7707...). In addition, we study dense packings of clusters of pair-linked ring tori (i.e., Hopf links), which can possess much higher densities than corresponding packings consisting of unlinked tori.

  3. [Identification of hashish samples with inductively coupled high-frequency plasma emission spectrometry and neutron activation analysis and data handling with neuronal networks. 1. Methods for the quantitative determination of characteristic trace elements].

    PubMed

    Lahl, H; Henke, G

    1997-11-01

    Neutron activation analysis (NAA) and inductively coupled plasma emission spectrometry (ICP-AES) were used to quantify the relative contents of Fe, Sc, Ce, Pa, Cr, Co, respectively the absolute contents of Cr, Zn, Mn, Fe, Mg, Al, Cu, Ti, Ca, Sr in hashish samples, seized in different countries. The samples were processed after dry ashing by means of instrumental NAA and after wet mineralization by means of ICP-AES. For determination of the sampling and measurement errors, one of the samples was analyzed repeatedly with both methods. Classifying hashish samples with regard to concentration of certain elements could be done by artificial neural networks with a modified backpropagation algorithm. By this way, identity and non identity of one unknown sample with one of many different samples as data pool can be ascertained, on principle. PMID:9446107

  4. Dense Regular Packings of Irregular Nonconvex Particles

    NASA Astrophysics Data System (ADS)

    de Graaf, Joost; van Roij, René; Dijkstra, Marjolein

    2011-10-01

    We present a new numerical scheme to study systems of nonconvex, irregular, and punctured particles in an efficient manner. We employ this method to analyze regular packings of odd-shaped bodies, both from a nanoparticle and from a computational geometry perspective. Besides determining close-packed structures for 17 irregular shapes, we confirm several conjectures for the packings of a large set of 142 convex polyhedra and extend upon these. We also prove that we have obtained the densest packing for both rhombicuboctahedra and rhombic enneacontrahedra and we have improved upon the packing of enneagons and truncated tetrahedra.

  5. Packed Bed Reactor Experiment

    NASA Video Gallery

    The purpose of the Packed Bed Reactor Experiment in low gravity is to determine how a mixture of gas and liquid flows through a packed bed in reduced gravity. A packed bed consists of a metal pipe ...

  6. Polarizable protein packing.

    PubMed

    Ng, Albert H; Snow, Christopher D

    2011-05-01

    To incorporate protein polarization effects within a protein combinatorial optimization framework, we decompose the polarizable force field AMOEBA into low order terms. Including terms up to the third-order provides a fair approximation to the full energy while maintaining tractability. We represent the polarizable packing problem for protein G as a hypergraph and solve for optimal rotamers with the FASTER combinatorial optimization algorithm. These approximate energy models can be improved to high accuracy [root mean square deviation (rmsd) < 1 kJ mol(-1)] via ridge regression. The resulting trained approximations are used to efficiently identify new, low-energy solutions. The approach is general and should allow combinatorial optimization of other many-body problems. PMID:21264879

  7. Packings of soft disks

    NASA Astrophysics Data System (ADS)

    Ziherl, Primoz; Vidmar, Marija

    2011-03-01

    We explore the stability of 2D ordered structures formed by soft disks treated as isotropic solid bodies. Using a variational model, we compute the equilibrium shapes and the elastic energy of disks in regular columnar, honeycomb, square, and hexagonal lattice. The results reproduce the Hertzian interaction in the regime of small deformations. The phase diagram of elastic disks is characterized by broad regions of phase coexistence; its main feature is that the coordination number of the stable phases decreases with density. These results may provide an insight into structure of the non-close-packed lattices observed in certain nanocolloidal systems. This work was supported by Slovenian Research Agency (grant No. P1-0055) and by EU through ITN COMPLOIDS (grant FP7-People-ITN-2008 No. 234810).

  8. Claw grip contact probe for flat packs

    NASA Astrophysics Data System (ADS)

    Shearer, J. W., Jr.

    1985-09-01

    A probe device including a unitary body 2 and a sliding plate means 44 for testing and diagnosing multi-lead electrical flat packs. The sliding plate means contains two sets of holes 52 into which are inserted spring-loaded electrical contact probes for making contact with the leads of the electrical flat pack. The unitary body 2 includes comb teeth for orienting the unitary body over the leads of the electrical flat pack, as well as gripping means having hook ends for securely fastening the probe device to the electrical flat pack being tested or diagnosed. The gripping means include an outwardly flared portion against which the sliding plate means exerts inward lateral pressure causing the hook ends to grip underneath the electrical flat pack at each corner thereof to securely clamp it in place. Included in unitary body 2 is at least one threaded hole which is sufficiently large to allow a size 4 to 40 machine screw to pass therethrough.

  9. Flat Pack Toy Design

    ERIC Educational Resources Information Center

    Hutcheson, Brian

    2007-01-01

    In this article, the author introduces the concept of flat pack toys. Flat pack toys are designed using a template on a single sheet of letter-sized card stock paper. Before being cut out and built into a three-dimensional toy, they are scanned into the computer and uploaded to a website. With the template accessible from the website, anyone with…

  10. TLC Pack Unpacked

    ERIC Educational Resources Information Center

    Oberhofer, Margret; Colpaert, Jozef

    2015-01-01

    TLC Pack stands for Teaching Languages to Caregivers and is a course designed to support migrants working or hoping to work in the caregiving sector. The TLC Pack resources range from A2 to B2 level of the Common European Framework of Reference for Languages (CEFR), and will be made available online in the six project languages: Dutch, English,…

  11. Graphitic packing removal tool

    DOEpatents

    Meyers, K.E.; Kolsun, G.J.

    1997-11-11

    Graphitic packing removal tools for removal of the seal rings in one piece are disclosed. The packing removal tool has a cylindrical base ring the same size as the packing ring with a surface finish, perforations, knurling or threads for adhesion to the seal ring. Elongated leg shanks are mounted axially along the circumferential center. A slit or slits permit insertion around shafts. A removal tool follower stabilizes the upper portion of the legs to allow a spanner wrench to be used for insertion and removal. 5 figs.

  12. Graphitic packing removal tool

    DOEpatents

    Meyers, Kurt Edward; Kolsun, George J.

    1997-01-01

    Graphitic packing removal tools for removal of the seal rings in one piece. he packing removal tool has a cylindrical base ring the same size as the packing ring with a surface finish, perforations, knurling or threads for adhesion to the seal ring. Elongated leg shanks are mounted axially along the circumferential center. A slit or slits permit insertion around shafts. A removal tool follower stabilizes the upper portion of the legs to allow a spanner wrench to be used for insertion and removal.

  13. Graphitic packing removal tool

    SciTech Connect

    Meyers, K.E.; Kolsun, G.J.

    1996-12-31

    Graphitic packing removal tools are described for removal of the seal rings in one piece from valves and pumps. The packing removal tool has a cylindrical base ring the same size as the packing ring with a surface finish, perforations, knurling or threads for adhesion to the seal ring. Elongated leg shanks are mounted axially along the circumferential center. A slit or slits permit insertion around shafts. A removal tool follower stabilizes the upper portion of the legs to allow a spanner wrench to be used for insertion and removal.

  14. Tiber winding pack design

    SciTech Connect

    Miller, J.R.

    1985-08-19

    A preliminary winding pack design was performed with the goal of showing feasibility of producing 10-T maximum field with a pack current density of 40 A.mm/sup -2/ while accepting 2.7 kW per coil nuclear heating. A cable-in-conduit conductor design (CIC), reported at the 6th Topical Meeting on the Technology of Fusion Energy, was based on several key issues.

  15. Pessimal shapes for packing

    NASA Astrophysics Data System (ADS)

    Kallus, Yoav

    2014-03-01

    The question of which convex shapes leave the most empty space in their densest packing is the subject of Reinhardt's conjecture in two dimensions and Ulam's conjecture in three dimensions. Such conjectures about pessimal packing shapes have proven notoriously difficult to make progress on. I show that the regular heptagon is a local pessimum among all convex shapes, and that the 3D ball is a local pessimum among origin-symmetric shapes. Any shape sufficiently close in the space of shapes to these local pessima can be packed at a greater efficiency than they. In two dimensions and in dimensions above three, the ball is not a local pessimum, so the situation in 3D is unusual and intriguing. I will discuss what conditions conspire to make the 3D ball a local pessimum and whether we can prove that it is also a global pessimum.

  16. The packing of particles

    SciTech Connect

    Cumberland, D.J.; Crawford, R.J.

    1987-01-01

    The wide range of information currently available on the packing of particles is brought together in this monograph. The authors' interest in the subject was initially aroused by the question of whether there is an optimum particle size distribution which would maximise the packing density of particles - a question which has attracted the interest of scientists and engineers for centuries. The densification of a powder mass is of relevance in a great many industries, among them the pharmaceutical, ceramic, powder metallurgy and civil engineering industries. In addition, the packing of regular - or irregular - shaped particles is also of relevance to a surprisingly large number of other industries and subject areas, i.e. the foundry industry, nuclear engineering, chemical engineering, crystallography, geology, biology, telecommunications, and so on. Accordingly, this book is written for a wide audience.

  17. DIY Fraction Pack.

    ERIC Educational Resources Information Center

    Graham, Alan; Graham, Louise

    2003-01-01

    Describes a very successful attempt to teach fractions to year 5 pupils based on pupils making their own fraction pack. Children decided for themselves how to make the fractional slices used in the activity using colored cardboard sheets and templates of a paper circle consisting of 24 equal slices. (Author/NB)

  18. Nutrition Action Pack.

    ERIC Educational Resources Information Center

    Sockut, Joanne; Stumpe, Stephanie

    One of five McDonald's Action Packs, these instructional materials integrate elementary school-level nutrition education into other disciplines--biology, sociology, physiology, mathematics, and art. Contents include four units consisting of twelve activities. Unit 1, Why You Need Food, is a self-examination of what is needed for growth, health,…

  19. AUTOmatic Message PACKing Facility

    Energy Science and Technology Software Center (ESTSC)

    2004-07-01

    AUTOPACK is a library that provides several useful features for programs using the Message Passing Interface (MPI). Features included are: 1. automatic message packing facility 2. management of send and receive requests. 3. management of message buffer memory. 4. determination of the number of anticipated messages from a set of arbitrary sends, and 5. deterministic message delivery for testing purposes.

  20. Packing Them In.

    ERIC Educational Resources Information Center

    Carter, Claudia

    1997-01-01

    This activity involves students investigating the mathematics of packaging and exploring various concepts in geometry, including area and the Pythagorean theorem. Mathematics comes out of the discussion of packaging cans into six-packs and focuses on the cost-effectiveness of the horizontal storage area used. Students learn how knowledge of…

  1. Sun Packs Double Punch

    NASA Video Gallery

    On August 3, the sun packed a double punch, emitting a M6.0-class flare at 9:43 am EDT. This video is of the second, slightly stronger M9.3-class flare at 11:41 pm EDT. Both flares had significant ...

  2. Economics Action Pack.

    ERIC Educational Resources Information Center

    McDonald's Corp., Oak Brook, IL.

    One of five McDonald's Action Packs, this learning package introduces intermediate grade students to basic economic concepts. The fourteen activities include the topics of consumption (4 activities), production (5), the market system (3), a pretest, and a posttest. Specific titles under consumption include The Wonderful Treasure Tree (introduction…

  3. Effect of packing method on the randomness of disc packings

    NASA Astrophysics Data System (ADS)

    Zhang, Z. P.; Yu, A. B.; Oakeshott, R. B. S.

    1996-06-01

    The randomness of disc packings, generated by random sequential adsorption (RSA), random packing under gravity (RPG) and Mason packing (MP) which gives a packing density close to that of the RSA packing, has been analysed, based on the Delaunay tessellation, and is evaluated at two levels, i.e. the randomness at individual subunit level which relates to the construction of a triangle from a given edge length distribution and the randomness at network level which relates to the connection between triangles from a given triangle frequency distribution. The Delaunay tessellation itself is also analysed and its almost perfect randomness at the two levels is demonstrated, which verifies the proposed approach and provides a random reference system for the present analysis. It is found that (i) the construction of a triangle subunit is not random for the RSA, MP and RPG packings, with the degree of randomness decreasing from the RSA to MP and then to RPG packing; (ii) the connection of triangular subunits in the network is almost perfectly random for the RSA packing, acceptable for the MP packing and not good for the RPG packing. Packing method is an important factor governing the randomness of disc packings.

  4. Packing fraction of continuous distributions

    NASA Astrophysics Data System (ADS)

    Brouwers, Jos

    2014-03-01

    This study addresses the packing and void fraction of polydisperse particles with geometric and lognormal size distribution. It is demonstrated that a bimodal discrete particle distribution can be transformed into said continuous particle-size distributions. Furthermore, original and exact expressions are presented that predict the packing fraction of these particle assemblies. For a number of particle shapes and their packing modes (close, loose) the applicable parameters are given. The closed-form analytical expression governing the packing fractions are thoroughly compared with empirical and computational data reported in the literature, and good agreement is found.

  5. Method for dense packing discovery

    NASA Astrophysics Data System (ADS)

    Kallus, Yoav; Elser, Veit; Gravel, Simon

    2010-11-01

    The problem of packing a system of particles as densely as possible is foundational in the field of discrete geometry and is a powerful model in the material and biological sciences. As packing problems retreat from the reach of solution by analytic constructions, the importance of an efficient numerical method for conducting de novo (from-scratch) searches for dense packings becomes crucial. In this paper, we use the divide and concur framework to develop a general search method for the solution of periodic constraint problems, and we apply it to the discovery of dense periodic packings. An important feature of the method is the integration of the unit-cell parameters with the other packing variables in the definition of the configuration space. The method we present led to previously reported improvements in the densest-known tetrahedron packing. Here, we use the method to reproduce the densest-known lattice sphere packings and the best-known lattice kissing arrangements in up to 14 and 11 dimensions, respectively, providing numerical evidence for their optimality. For nonspherical particles, we report a dense packing of regular four-dimensional simplices with density ϕ=128/219≈0.5845 and with a similar structure to the densest-known tetrahedron packing.

  6. Granular packings and fault zones

    PubMed

    Astrom; Herrmann; Timonen

    2000-01-24

    The failure of a two-dimensional packing of elastic grains is analyzed using a numerical model. The packing fails through formation of shear bands or faults. During failure there is a separation of the system into two grain-packing states. In a shear band, local "rotating bearings" are spontaneously formed. The bearing state is favored in a shear band because it has a low stiffness against shearing. The "seismic activity" distribution in the packing has the same characteristics as that of the earthquake distribution in tectonic faults. The directions of the principal stresses in a bearing are reminiscent of those found at the San Andreas Fault. PMID:11017335

  7. Random very loose packings.

    PubMed

    Ciamarra, Massimo Pica; Coniglio, Antonio

    2008-09-19

    We measure the number Omega(phi) of mechanically stable states of volume fraction phi of a granular assembly under gravity. The granular entropy S(phi)=logOmega(phi) vanishes both at high density, at phi approximately equal to phi_rcp, and a low density, at phi approximately equal to phi_rvlp, where phi_rvlp is a new lower bound we call random very loose pack. phi_rlp is the volume fraction where the entropy is maximal. These findings allow for a clear explanation of compaction experiments and provide the first first-principle definition of the random loose volume fraction. In the context of the statistical mechanics approach to static granular materials, states with phi

  8. Packing Products: Polystyrene vs. Cornstarch

    ERIC Educational Resources Information Center

    Starr, Suzanne

    2009-01-01

    Packing materials such as polystyrene take thousands of years to decompose, whereas packing peanuts made from cornstarch, which some companies are now using, can serve the same purpose, but dissolve in water. The author illustrates this point to her class one rainy day using the sculptures students made from polystyrene and with the cornstarch…

  9. Heterogeneity of packing: structural approach.

    PubMed Central

    Kurochkina, N.; Privalov, G.

    1998-01-01

    Analysis of the heterogeneity of packing in proteins showed that different groups of the protein preferentially contribute to low- or high-density regions. Statistical distribution reveals the two preferable values for packing density in the form of two peaks. One peak occurs in the range of densities 0.55-0.65, the other occurs in the range 0.75-0.8. The high-density peak is originated primarily by high packing inside the hydrogen bonded backbone and to some extent by side chains. Polar/charged and apolar side chains both contribute to the low-density peak. The average packing density values of individual atomic groups significantly vary for backbone atoms as well as for side chain atoms. The carbonyl oxygen atoms of protein backbone and the end groups of side chains show lower packing density than the rest of the protein. The side-chain atomic groups of a secondary structure element when packed against the neighboring secondary structure element form stronger contacts with the side chains of this element than with its backbone. Analysis of the low-density regions around each buried peptide group was done for the set of proteins with different types of packing, including alpha-alpha, alpha-beta, and beta-beta packing. It was shown that cavities are regularly situated in the groove of secondary structure element packed against neighboring elements for all types of packing. Low density in the regions surrounding the peptide groups and the end groups of side chains can be explained by their positioning next to a cavity formed upon the association of secondary structure elements. The model proposed can be applied to the analysis of protein internal motions, mechanisms of cellular signal transduction, diffusion through protein matrix, and other events. PMID:9568896

  10. 7 CFR 51.310 - Packing requirements.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... STANDARDS) United States Standards for Grades of Apples Packing Requirements § 51.310 Packing requirements. (a) Apples tray packed or cell packed in cartons shall be arranged according to approved and... that apples are of the proper size for molds or cell compartments in which they are packed, and...

  11. 7 CFR 51.310 - Packing requirements.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... STANDARDS) United States Standards for Grades of Apples Packing Requirements § 51.310 Packing requirements. (a) Apples tray packed or cell packed in cartons shall be arranged according to approved and... that apples are of the proper size for molds or cell compartments in which they are packed, and...

  12. 7 CFR 51.310 - Packing requirements.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... STANDARDS) United States Standards for Grades of Apples Packing Requirements § 51.310 Packing requirements. (a) Apples tray packed or cell packed in cartons shall be arranged according to approved and... that apples are of the proper size for molds or cell compartments in which they are packed, and...

  13. Dynamics of random packings in granular flow

    NASA Astrophysics Data System (ADS)

    Rycroft, Chris H.; Bazant, Martin Z.; Grest, Gary S.; Landry, James W.

    2006-05-01

    We present a multiscale simulation algorithm for amorphous materials, which we illustrate and validate in a canonical case of dense granular flow. Our algorithm is based on the recently proposed spot model, where particles in a dense random packing undergo chainlike collective displacements in response to diffusing “spots” of influence, carrying a slight excess of interstitial free volume. We reconstruct the microscopic dynamics of particles from the “coarse grained” dynamics of spots by introducing a localized particle relaxation step after each spot-induced block displacement, simply to enforce packing constraints with a (fairly arbitrary) soft-core repulsion. To test the model, we study to what extent it can describe the dynamics of up to 135 000 frictional, viscoelastic spheres in granular drainage simulated by the discrete-element method (DEM). With only five fitting parameters (the radius, volume, diffusivity, drift velocity, and injection rate of spots), we find that the spot simulations are able to largely reproduce not only the mean flow and diffusion, but also some subtle statistics of the flowing packings, such as spatial velocity correlations and many-body structural correlations. The spot simulations run over 100 times faster than the DEM and demonstrate the possibility of multiscale modeling for amorphous materials, whenever a suitable model can be devised for the coarse-grained spot dynamics.

  14. Valve stem and packing assembly

    DOEpatents

    Wordin, John J.

    1991-01-01

    A valve stem and packing assembly is provided in which a rotatable valve stem includes a first tractrix surface for sliding contact with a stem packing and also includes a second tractrix surface for sliding contact with a bonnet. Force is applied by means of a spring, gland flange, and gland on the stem packing so the stem packing seals to the valve stem and bonnet. This configuration serves to create and maintain a reliable seal between the stem packing and the valve stem. The bonnet includes a second complementary tractrix surface for contacting the second sliding tractrix surface, the combination serving as a journal bearing for the entire valve stem and packing assembly. The journal bearing so configured is known as a Schiele's pivot. The Schiele's pivot also serves to maintain proper alignment of the valve stem with respect to the bonnet. Vertical wear between the surfaces of the Schiele's pivot is uniform at all points of contact between the second sliding tractrix surface and the second complementary tractrix surface of a bonnet. The valve stem is connected to a valve plug by means of a slip joint. The valve is opened and closed by rotating the valve stem. The slip joint compensates for wear on the Schiele's pivot and on the valve plug. A ledge is provided on the valve bonnet for the retaining nut to bear against. The ledge prevents overtightening of the retaining nut and the resulting excessive friction between stem and stem packing.

  15. Valve stem and packing assembly

    DOEpatents

    Wordin, J.J.

    1991-09-03

    A valve stem and packing assembly is provided in which a rotatable valve stem includes a first tractrix surface for sliding contact with a stem packing and also includes a second tractrix surface for sliding contact with a bonnet. Force is applied by means of a spring, gland flange, and gland on the stem packing so the stem packing seals to the valve stem and bonnet. This configuration serves to create and maintain a reliable seal between the stem packing and the valve stem. The bonnet includes a second complementary tractrix surface for contacting the second sliding tractrix surface, the combination serving as a journal bearing for the entire valve stem and packing assembly. The journal bearing so configured is known as a Schiele's pivot. The Schiele's pivot also serves to maintain proper alignment of the valve stem with respect to the bonnet. Vertical wear between the surfaces of the Schiele's pivot is uniform at all points of contact between the second sliding tractrix surface and the second complementary tractrix surface of a bonnet. The valve stem is connected to a valve plug by means of a slip joint. The valve is opened and closed by rotating the valve stem. The slip joint compensates for wear on the Schiele's pivot and on the valve plug. A ledge is provided on the valve bonnet for the retaining nut to bear against. The ledge prevents over tightening of the retaining nut and the resulting excessive friction between stem and stem packing. 2 figures.

  16. Method for packing chromatographic beds

    DOEpatents

    Freeman, David H.; Angeles, Rosalie M.; Keller, Suzanne

    1991-01-01

    Column chromatography beds are packed through the application of static force. A slurry of the chromatography bed material and a non-viscous liquid is filled into the column plugged at one end, and allowed to settle. The column is transferred to a centrifuge, and centrifuged for a brief period of time to achieve a predetermined packing level, at a range generally of 100-5,000 gravities. Thereafter, the plug is removed, other fixtures may be secured, and the liquid is allowed to flow out through the bed. This results in an evenly packed bed, with no channeling or preferential flow characteristics.

  17. Heating Luggage Sends Bedbugs Packing

    MedlinePlus

    ... gov/news/fullstory_160234.html Heating Luggage Sends Bedbugs Packing Just 6 minutes at about 160 degrees ... 3, 2016 WEDNESDAY, Aug. 3, 2016 (HealthDay News) -- Bedbugs, those creepy crawly insects that feed on your ...

  18. Are proteins well-packed?

    PubMed

    Liang, J; Dill, K A

    2001-08-01

    The average packing density inside proteins is as high as in crystalline solids. Does this mean proteins are well-packed? We go beyond average densities, and look at the full distribution functions of free volumes inside proteins. Using a new and rigorous Delaunay triangulation method for parsing space into empty and filled regions, we introduce formal definitions of interior and surface packing densities. Although proteins look like organic crystals by the criterion of average density, they look more like liquids and glasses by the criterion of their free volume distributions. The distributions are broad, and the scalings of volume-to-surface, volume-to-cluster-radius, and numbers of void versus volume show that the interiors of proteins are more like randomly packed spheres near their percolation threshold than like jigsaw puzzles. We find that larger proteins are packed more loosely than smaller proteins. And we find that the enthalpies of folding (per amino acid) are independent of the packing density of a protein, indicating that van der Waals interactions are not a dominant component of the folding forces. PMID:11463623

  19. Pattern formations and optimal packing.

    PubMed

    Mityushev, Vladimir

    2016-04-01

    Patterns of different symmetries may arise after solution to reaction-diffusion equations. Hexagonal arrays, layers and their perturbations are observed in different models after numerical solution to the corresponding initial-boundary value problems. We demonstrate an intimate connection between pattern formations and optimal random packing on the plane. The main study is based on the following two points. First, the diffusive flux in reaction-diffusion systems is approximated by piecewise linear functions in the framework of structural approximations. This leads to a discrete network approximation of the considered continuous problem. Second, the discrete energy minimization yields optimal random packing of the domains (disks) in the representative cell. Therefore, the general problem of pattern formations based on the reaction-diffusion equations is reduced to the geometric problem of random packing. It is demonstrated that all random packings can be divided onto classes associated with classes of isomorphic graphs obtained from the Delaunay triangulation. The unique optimal solution is constructed in each class of the random packings. If the number of disks per representative cell is finite, the number of classes of isomorphic graphs, hence, the number of optimal packings is also finite. PMID:26852668

  20. PlanetPack: Radial-velocity time-series analysis tool

    NASA Astrophysics Data System (ADS)

    Baluev, Roman V.

    2013-11-01

    PlanetPack facilitates and standardizes the advanced analysis of radial velocity (RV) data for the goal of exoplanets detection, characterization, and basic dynamical N-body simulations. PlanetPack is a command-line interpreter that can run either in an interactive mode or in a batch mode of automatic script interpretation.

  1. 7 CFR 51.1217 - Standard pack.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Standards for Grades of Peaches Standard Pack § 51.1217 Standard pack. (a) Each package shall be packed so that the peaches in the shown face shall be reasonably representative in size, color and quality of the contents of the package. (b) Peaches packed in U.S. Standard bushel baskets, or half-bushel baskets,...

  2. 7 CFR 51.1217 - Standard pack.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ..., CERTIFICATION, AND STANDARDS) United States Standards for Grades of Peaches Standard Pack § 51.1217 Standard pack. (a) Each package shall be packed so that the peaches in the shown face shall be reasonably representative in size, color and quality of the contents of the package. (b) Peaches packed in U.S....

  3. 7 CFR 51.1217 - Standard pack.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Standards for Grades of Peaches Standard Pack § 51.1217 Standard pack. (a) Each package shall be packed so that the peaches in the shown face shall be reasonably representative in size, color and quality of the contents of the package. (b) Peaches packed in U.S. Standard bushel baskets, or half-bushel baskets,...

  4. 7 CFR 51.1217 - Standard pack.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ..., CERTIFICATION, AND STANDARDS) United States Standards for Grades of Peaches Standard Pack § 51.1217 Standard pack. (a) Each package shall be packed so that the peaches in the shown face shall be reasonably representative in size, color and quality of the contents of the package. (b) Peaches packed in U.S....

  5. 7 CFR 51.1527 - Standard pack.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Standards for Grades of Fresh Plums and Prunes Standard Pack § 51.1527 Standard pack. (a) Packing. (1) All... plums or prunes in the top layer of any package shall be reasonably representative in quality and size of those in the remainder of the package. (3) “Well filled” means that the plums or prunes packed...

  6. 7 CFR 51.1527 - Standard pack.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Standards for Grades of Fresh Plums and Prunes Standard Pack § 51.1527 Standard pack. (a) Packing. (1) All... plums or prunes in the top layer of any package shall be reasonably representative in quality and size of those in the remainder of the package. (3) “Well filled” means that the plums or prunes packed...

  7. 7 CFR 51.1527 - Standard pack.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Standards for Grades of Fresh Plums and Prunes Standard Pack § 51.1527 Standard pack. (a) Packing. (1) All... plums or prunes in the top layer of any package shall be reasonably representative in quality and size of those in the remainder of the package. (3) “Well filled” means that the plums or prunes packed...

  8. 7 CFR 51.1217 - Standard pack.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Standards for Grades of Peaches Standard Pack § 51.1217 Standard pack. (a) Each package shall be packed so that the peaches in the shown face shall be reasonably representative in size, color and quality of the contents of the package. (b) Peaches packed in U.S. Standard bushel baskets, or half-bushel baskets,...

  9. 7 CFR 51.310 - Packing requirements.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... (INSPECTION, CERTIFICATION, AND STANDARDS) United States Standards for Grades of Apples Packing Requirements § 51.310 Packing requirements. (a) Apples tray packed or cell packed in cartons shall be arranged.... 3 2 “Fairly tight” means that apples are of the proper size for molds or cell compartments in...

  10. 7 CFR 51.310 - Packing requirements.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... (INSPECTION, CERTIFICATION, AND STANDARDS) United States Standards for Grades of Apples Packing Requirements § 51.310 Packing requirements. (a) Apples tray packed or cell packed in cartons shall be arranged.... 3 2 “Fairly tight” means that apples are of the proper size for molds or cell compartments in...

  11. Valve packings conquer fugitive emissions

    SciTech Connect

    1995-11-01

    In the early 1990s, when the US Environmental Protection Agency (EPA; Washington, D.C.) declared its intent to regulate fugitive emissions from valve-stem leakage, much of the chemical process industries (CPI) responded with fear and uncertainty. The biggest fear was that valve packing would not meet the required limits on leak rates and that expensive bellows seals may be required on many applications. The uncertainly was about how much it would cost. Today, for the most part, these concerns have been mitigated. It is estimated that about 80--90% of valves satisfy the emission requirements. The rest need some improvement in their packing systems to meet the regulations. Generally, these valves can be brought within compliance if the packing designers follow a few basic principles: Employ less-pliable outer rings and more-pliable inner rings; and don`t use excessive packing. While interest in valve packing remains high, mechanical seals continue to become more user-friendly. Many of those covered below are designed to run dry, and some can even tolerate high shaft-wobble without damage. Also look for improved flange gaskets and a host of seals to protect bearings. Twenty-one summaries are presented on new products and services.

  12. Hard sphere packings within cylinders.

    PubMed

    Fu, Lin; Steinhardt, William; Zhao, Hao; Socolar, Joshua E S; Charbonneau, Patrick

    2016-02-23

    Arrangements of identical hard spheres confined to a cylinder with hard walls have been used to model experimental systems, such as fullerenes in nanotubes and colloidal wire assembly. Finding the densest configurations, called close packings, of hard spheres of diameter σ in a cylinder of diameter D is a purely geometric problem that grows increasingly complex as D/σ increases, and little is thus known about the regime for D > 2.873σ. In this work, we extend the identification of close packings up to D = 4.00σ by adapting Torquato-Jiao's adaptive-shrinking-cell formulation and sequential-linear-programming (SLP) technique. We identify 17 new structures, almost all of them chiral. Beyond D ≈ 2.85σ, most of the structures consist of an outer shell and an inner core that compete for being close packed. In some cases, the shell adopts its own maximum density configuration, and the stacking of core spheres within it is quasiperiodic. In other cases, an interplay between the two components is observed, which may result in simple periodic structures. In yet other cases, the very distinction between the core and shell vanishes, resulting in more exotic packing geometries, including some that are three-dimensional extensions of structures obtained from packing hard disks in a circle. PMID:26843132

  13. Sleeping distance in wild wolf packs

    USGS Publications Warehouse

    Knick, S.T.; Mech, L.D.

    1980-01-01

    Sleeping distances were observed among members of 13 wild wolf (Canis lupus) packs and 11 pairs in northeastern Minnesota to determine if the distances correlated with pack size and composition. The study utilized aerial radio-tracking and observation during winter. Pack size and number of adults per pack were inversely related to pack average sleeping distance and variability. No correlation between sleeping distance and microclimate was observed. Possible relationships between social bonding and our results are discussed.

  14. Cylinder valve packing nut studies

    SciTech Connect

    Blue, S.C.

    1991-12-31

    The design, manufacture, and use of cylinder valve packing nuts have been studied to improve their resistance to failure from stress corrosion cracking. Stress frozen photoelastic models have been analyzed to measure the stress concentrations at observed points of failure. The load effects induced by assembly torque and thermal expansion of stem packing were observed by strain gaging nuts. The effects of finishing operations and heat treatment were studied by the strain gage hole boring and X-ray methods. Modifications of manufacturing and operation practices are reducing the frequency of stress corrosion failures.

  15. Pack cementation coatings for alloys

    SciTech Connect

    He, Yi-Rong; Zheng, Minhui; Rapp, R.A.

    1996-08-01

    The halide-activated pack cementation process was modified to produce a Ge-doped silicide diffusion coating on a Cr-Cr{sub 2}Nb alloy in a single processing step. The morphology and composition of the coating depended both on the composition of the pack and on the composition and microstructure of the substrate. Higher Ge content in the pack suppressed the formation of CrSi{sub 2} and reduced the growth kinetics of the coating. Ge was not homogeneously distributed in the coatings. In cyclic and isothermal oxidation in air at 700 and 1050{degrees}C, the Ge-doped silicide coating protected the Cr-Nb alloys from significant oxidation by the formation of a Ge-doped silica film. The codeposition and diffusion of aluminum and chromium into low alloy steel have been achieved using elemental Al and Cr powders and a two-step pack cementation process. Sequential process treatments at 925{degrees}C and 1150{degrees}C yield dense and uniform ferrite coatings, whose compositions are close to either Fe{sub 3}Al or else FeAl plus a lower Cr content, when processed under different conditions. The higher content of Al in the coatings was predicted by thermodynamic calculations of equilibrium in the gas phase. The effect of the particle size of the metal powders on the surface composition of the coating has been studied for various combinations of Al and Cr powders.

  16. Computer simulations of particle packing

    SciTech Connect

    Cesarano, J. III; McEuen, M.J.; Swiler, T.

    1996-09-01

    Computer code has been developed to rapidly simulate the random packing of disks and spheres in two and three dimensions. Any size distribution may be packed. The code simulates varying degrees of inter particle conditions ranging from sticky to free flowing. The code will also calculate the overall packing density, density distributions, and void size distributions (in two dimensions). An important aspect of the code is that it is written in C++ and incorporates a user-friendly graphical interface for standard Macintosh and Power PC platforms. Investigations as to how well the code simulates the realistic random packing have begun. The code has been developed in consideration of the problem of filling a container (or die) with spray-dried granules of ceramic powder (represented by spheres). Although not presented here, the futuristic goal of this work is to give users the ability to predict homogeneity of filled dies prior to dry pressing. Additionally, this software has educational utility for studying relationships between particle size distributions and macrostructures.

  17. Ecology and Energy Action Pack.

    ERIC Educational Resources Information Center

    McDonald's Corp., Oak Brook, IL.

    One of five McDonald's Action Packs, these elementary school-level instructional materials are for use as an introduction to existing units of study, supplements to a textbook, or a source of special projects for environmental education. Contents include these six units: Make Your Own Ecology Mini-spinner, Let's Look at a Food Chain, Drip the…

  18. Set covering, partition and packing

    SciTech Connect

    Hulme, B.L.; Baca, L.S.

    1984-03-01

    Set covering problems are known to be solvable by Boolean algebraic methods. This report shows that set partition and set packing problems can be solved by the same algebraic methods because these problems can be converted into covering problems. Many applications are possible including security patrol assignment which is used as an example.

  19. Microfabricated packed gas chromatographic column

    DOEpatents

    Kottenstette, Richard; Matzke, Carolyn M.; Frye-Mason, Gregory C.

    2003-12-16

    A new class of miniaturized gas chromatographic columns has been invented. These chromatographic columns are formed using conventional micromachining techniques, and allow packed columns having lengths on the order of a meter to be fabricated with a footprint on the order of a square centimeter.

  20. 7 CFR 984.15 - Pack.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE WALNUTS GROWN IN CALIFORNIA Order Regulating Handling Definitions § 984.15 Pack. Pack means to bleach, clean, grade, shell or otherwise prepare walnuts for market as inshell or shelled walnuts....

  1. 7 CFR 984.15 - Pack.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... ORDERS; FRUITS, VEGETABLES, NUTS), DEPARTMENT OF AGRICULTURE WALNUTS GROWN IN CALIFORNIA Order Regulating Handling Definitions § 984.15 Pack. Pack means to bleach, clean, grade, shell or otherwise prepare walnuts for market as inshell or shelled walnuts....

  2. 7 CFR 984.15 - Pack.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE WALNUTS GROWN IN CALIFORNIA Order Regulating Handling Definitions § 984.15 Pack. Pack means to bleach, clean, grade, shell or otherwise prepare walnuts for market as inshell or shelled walnuts....

  3. 7 CFR 984.15 - Pack.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... ORDERS; FRUITS, VEGETABLES, NUTS), DEPARTMENT OF AGRICULTURE WALNUTS GROWN IN CALIFORNIA Order Regulating Handling Definitions § 984.15 Pack. Pack means to bleach, clean, grade, shell or otherwise prepare walnuts for market as inshell or shelled walnuts....

  4. 7 CFR 984.15 - Pack.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE WALNUTS GROWN IN CALIFORNIA Order Regulating Handling Definitions § 984.15 Pack. Pack means to bleach, clean, grade, shell or otherwise prepare walnuts for market as inshell or shelled walnuts....

  5. 7 CFR 966.11 - Pack.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE TOMATOES GROWN IN FLORIDA Order Regulating Handling Definitions § 966.11 Pack. Pack means any of the packs of tomatoes as defined and set forth in the United States Standards for Fresh Tomatoes issued by the United States Department of Agriculture (§§...

  6. 7 CFR 51.1527 - Standard pack.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ..., CERTIFICATION, AND STANDARDS) United States Standards for Grades of Fresh Plums and Prunes Standard Pack § 51... the approved and recognized methods. (2) The plums or prunes in the top layer of any package shall be...” means that the plums or prunes packed in loose or volume filled containers are packed within 1 inch...

  7. 7 CFR 51.1527 - Standard pack.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ..., CERTIFICATION, AND STANDARDS) United States Standards for Grades of Fresh Plums and Prunes Standard Pack § 51... the approved and recognized methods. (2) The plums or prunes in the top layer of any package shall be...” means that the plums or prunes packed in loose or volume filled containers are packed within 1 inch...

  8. Force distribution/transmission in amorphous and crystalline packings of spheres

    NASA Astrophysics Data System (ADS)

    An, Xizhong; Huang, Fei

    2013-06-01

    In this paper, the discrete element modeling (DEM) was used to study the force distributions/transmissions in the packings of amorphous and crystalline states generated by equal spheres subjected to an external load (of a large sphere) applied on the top of a packing. Crystalline packings such as {100}-and {111}-oriented face centered cubic (FCC), hexagonal close packed (HCP) and body centered cubic (BCC) were considered. The results show that the forces among the particles in these packings are quite different, with different force chains identified with different structures. For amorphous packings, the force chain supporting the external load gives a conical shape. The force chain in a crystalline packing is mainly of a pyramid shape and the forces therein are transmitted along the crystalline lattice. For {100}-FCC, {111}-FCC, and BCC other than HCP, the forces transmit along straight lines with different orientations. In crystalline packings, the forces in the chains are uniformly distributed in each layer and decrease linearly with the height. The force distributions in amorphous and crystalline granular packings are structure-dependent.

  9. Beyond packing of hard spheres: The effects of core softness, non-additivity, intermediate-range repulsion, and many-body interactions on the glass-forming ability of bulk metallic glasses

    SciTech Connect

    Zhang, Kai; Fan, Meng; Liu, Yanhui; Schroers, Jan; Shattuck, Mark D.; O’Hern, Corey S.

    2015-11-14

    When a liquid is cooled well below its melting temperature at a rate that exceeds the critical cooling rate R{sub c}, the crystalline state is bypassed and a metastable, amorphous glassy state forms instead. R{sub c} (or the corresponding critical casting thickness d{sub c}) characterizes the glass-forming ability (GFA) of each material. While silica is an excellent glass-former with small R{sub c} < 10{sup −2} K/s, pure metals and most alloys are typically poor glass-formers with large R{sub c} > 10{sup 10} K/s. Only in the past thirty years have bulk metallic glasses (BMGs) been identified with R{sub c} approaching that for silica. Recent simulations have shown that simple, hard-sphere models are able to identify the atomic size ratio and number fraction regime where BMGs exist with critical cooling rates more than 13 orders of magnitude smaller than those for pure metals. However, there are a number of other features of interatomic potentials beyond hard-core interactions. How do these other features affect the glass-forming ability of BMGs? In this manuscript, we perform molecular dynamics simulations to determine how variations in the softness and non-additivity of the repulsive core and form of the interatomic pair potential at intermediate distances affect the GFA of binary alloys. These variations in the interatomic pair potential allow us to introduce geometric frustration and change the crystal phases that compete with glass formation. We also investigate the effect of tuning the strength of the many-body interactions from zero to the full embedded atom model on the GFA for pure metals. We then employ the full embedded atom model for binary BMGs and show that hard-core interactions play the dominant role in setting the GFA of alloys, while other features of the interatomic potential only change the GFA by one to two orders of magnitude. Despite their perturbative effect, understanding the detailed form of the intermetallic potential is important for

  10. Beyond packing of hard spheres: The effects of core softness, non-additivity, intermediate-range repulsion, and many-body interactions on the glass-forming ability of bulk metallic glasses

    NASA Astrophysics Data System (ADS)

    Zhang, Kai; Fan, Meng; Liu, Yanhui; Schroers, Jan; Shattuck, Mark D.; O'Hern, Corey S.

    2015-11-01

    When a liquid is cooled well below its melting temperature at a rate that exceeds the critical cooling rate Rc, the crystalline state is bypassed and a metastable, amorphous glassy state forms instead. Rc (or the corresponding critical casting thickness dc) characterizes the glass-forming ability (GFA) of each material. While silica is an excellent glass-former with small Rc < 10-2 K/s, pure metals and most alloys are typically poor glass-formers with large Rc > 1010 K/s. Only in the past thirty years have bulk metallic glasses (BMGs) been identified with Rc approaching that for silica. Recent simulations have shown that simple, hard-sphere models are able to identify the atomic size ratio and number fraction regime where BMGs exist with critical cooling rates more than 13 orders of magnitude smaller than those for pure metals. However, there are a number of other features of interatomic potentials beyond hard-core interactions. How do these other features affect the glass-forming ability of BMGs? In this manuscript, we perform molecular dynamics simulations to determine how variations in the softness and non-additivity of the repulsive core and form of the interatomic pair potential at intermediate distances affect the GFA of binary alloys. These variations in the interatomic pair potential allow us to introduce geometric frustration and change the crystal phases that compete with glass formation. We also investigate the effect of tuning the strength of the many-body interactions from zero to the full embedded atom model on the GFA for pure metals. We then employ the full embedded atom model for binary BMGs and show that hard-core interactions play the dominant role in setting the GFA of alloys, while other features of the interatomic potential only change the GFA by one to two orders of magnitude. Despite their perturbative effect, understanding the detailed form of the intermetallic potential is important for designing BMGs with cm or greater casting thickness.

  11. Beyond packing of hard spheres: The effects of core softness, non-additivity, intermediate-range repulsion, and many-body interactions on the glass-forming ability of bulk metallic glasses.

    PubMed

    Zhang, Kai; Fan, Meng; Liu, Yanhui; Schroers, Jan; Shattuck, Mark D; O'Hern, Corey S

    2015-11-14

    When a liquid is cooled well below its melting temperature at a rate that exceeds the critical cooling rate Rc, the crystalline state is bypassed and a metastable, amorphous glassy state forms instead. Rc (or the corresponding critical casting thickness dc) characterizes the glass-forming ability (GFA) of each material. While silica is an excellent glass-former with small Rc < 10(-2) K/s, pure metals and most alloys are typically poor glass-formers with large Rc > 10(10) K/s. Only in the past thirty years have bulk metallic glasses (BMGs) been identified with Rc approaching that for silica. Recent simulations have shown that simple, hard-sphere models are able to identify the atomic size ratio and number fraction regime where BMGs exist with critical cooling rates more than 13 orders of magnitude smaller than those for pure metals. However, there are a number of other features of interatomic potentials beyond hard-core interactions. How do these other features affect the glass-forming ability of BMGs? In this manuscript, we perform molecular dynamics simulations to determine how variations in the softness and non-additivity of the repulsive core and form of the interatomic pair potential at intermediate distances affect the GFA of binary alloys. These variations in the interatomic pair potential allow us to introduce geometric frustration and change the crystal phases that compete with glass formation. We also investigate the effect of tuning the strength of the many-body interactions from zero to the full embedded atom model on the GFA for pure metals. We then employ the full embedded atom model for binary BMGs and show that hard-core interactions play the dominant role in setting the GFA of alloys, while other features of the interatomic potential only change the GFA by one to two orders of magnitude. Despite their perturbative effect, understanding the detailed form of the intermetallic potential is important for designing BMGs with cm or greater casting

  12. Combinatorically Prescribed Packings and Applications to Conformal and Quasiconformal Maps

    NASA Astrophysics Data System (ADS)

    Schramm, Oded

    2007-09-01

    The Andreev-Thurston Circle Packing Theorem is generalized to packings of convex bodies in planar simply connected domains. This turns out to be a useful tool for constructing conformal and quasiconformal mappings with interesting geometric properties. We attempt to illustrate this with a few results about uniformizations of finitely connected planar domains. For example, the following variation of a theorem by Courant, Manel and Shiffman is proved and generalized. If G is an n+1-connected bounded planar domain, H is a simply connected bounded planar domain, and P_1,P_2,...,P_n are (compact) planar convex bodies, then sets P_j' can be found so that G is conformally equivalent to H-\\cup p_{j=1}^n P_j', and each P_j' is either a point, or is positively homothetic to P_j.

  13. Kinetics of pack aluminization of nickel

    NASA Technical Reports Server (NTRS)

    Seigle, L. L.; Gupta, B. K.; Shankar, R.; Sarkhel, A. K.

    1978-01-01

    The kinetics of pack aluminization of unalloyed nickel in packs of varying aluminum activity with various halide activators were studied. Surface compositions of the coatings as functions of time, temperature, and pack composition were obtained in order to establish the boundary conditions for diffusion in the system. The structure of the packs was also examined in order to clarify the mechanism of aluminum transport. The results indicate that the kinetics of pack aluminization are controlled jointly by gas diffusion in the pack and solid diffusion in the coating. Levine and Caves' model for gas diffusion was combined with calculations of rates of diffusion in the solid to formulate a more complete theory for the kinetics of pack aluminization.

  14. Numerical simulation of a shear-thinning fluid through packed spheres

    NASA Astrophysics Data System (ADS)

    Liu, Hai Long; Moon, Jong Sin; Hwang, Wook Ryol

    2012-12-01

    Flow behaviors of a non-Newtonian fluid in spherical microstructures have been studied by a direct numerical simulation. A shear-thinning (power-law) fluid through both regular and randomly packed spheres has been numerically investigated in a representative unit cell with the tri-periodic boundary condition, employing a rigorous three-dimensional finite-element scheme combined with fictitious-domain mortar-element methods. The present scheme has been validated for the classical spherical packing problems with literatures. The flow mobility of regular packing structures, including simple cubic (SC), body-centered cubic (BCC), face-centered cubic (FCC), as well as randomly packed spheres, has been investigated quantitatively by considering the amount of shear-thinning, the pressure gradient and the porosity as parameters. Furthermore, the mechanism leading to the main flow path in a highly shear-thinning fluid through randomly packed spheres has been discussed.

  15. The Packing of Granular Polymer Chains

    SciTech Connect

    Zou, Ling-Nan; Cheng, Xiang; Rivers, Mark L.; Jaeger, Heinrich M.; Nagel, Sidney R.; UC

    2009-12-01

    Rigid particles pack into structures, such as sand dunes on the beach, whose overall stability is determined by the average number of contacts between particles. However, when packing spatially extended objects with flexible shapes, additional concepts must be invoked to understand the stability of the resulting structure. Here, we examine the disordered packing of chains constructed out of flexibly connected hard spheres. Using x-ray tomography, we find that long chains pack into a low-density structure whose mechanical rigidity is mainly provided by the backbone. On compaction, randomly oriented, semi-rigid loops form along the chain, and the packing of chains can be understood as the jamming of these elements. Finally, we uncover close similarities between the packing of chains and the glass transition in polymers.

  16. Random packing of spheres in Menger sponge

    NASA Astrophysics Data System (ADS)

    Cieśla, Michał; Barbasz, Jakub

    2013-06-01

    Random packing of spheres inside fractal collectors of dimension 2 < d < 3 is studied numerically using Random Sequential Adsorption (RSA) algorithm. The paper focuses mainly on the measurement of random packing saturation limit. Additionally, scaling properties of density autocorrelations in the obtained packing are analyzed. The RSA kinetics coefficients are also measured. Obtained results allow to test phenomenological relation between random packing saturation density and collector dimension. Additionally, performed simulations together with previously obtained results confirm that, in general, the known dimensional relations are obeyed by systems having non-integer dimension, at least for d < 3.

  17. Random packing of spheres in Menger sponge.

    PubMed

    Cieśla, Michał; Barbasz, Jakub

    2013-06-01

    Random packing of spheres inside fractal collectors of dimension 2 < d < 3 is studied numerically using Random Sequential Adsorption (RSA) algorithm. The paper focuses mainly on the measurement of random packing saturation limit. Additionally, scaling properties of density autocorrelations in the obtained packing are analyzed. The RSA kinetics coefficients are also measured. Obtained results allow to test phenomenological relation between random packing saturation density and collector dimension. Additionally, performed simulations together with previously obtained results confirm that, in general, the known dimensional relations are obeyed by systems having non-integer dimension, at least for d < 3. PMID:23758392

  18. 7 CFR 982.11 - Pack.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE HAZELNUTS GROWN IN OREGON AND WASHINGTON... according to size, internal quality, and external appearance and condition of hazelnuts packed in...

  19. 7 CFR 982.11 - Pack.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... ORDERS; FRUITS, VEGETABLES, NUTS), DEPARTMENT OF AGRICULTURE HAZELNUTS GROWN IN OREGON AND WASHINGTON... according to size, internal quality, and external appearance and condition of hazelnuts packed in...

  20. 7 CFR 982.11 - Pack.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE HAZELNUTS GROWN IN OREGON AND WASHINGTON... according to size, internal quality, and external appearance and condition of hazelnuts packed in...

  1. 7 CFR 982.11 - Pack.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE HAZELNUTS GROWN IN OREGON AND WASHINGTON... according to size, internal quality, and external appearance and condition of hazelnuts packed in...

  2. 7 CFR 982.11 - Pack.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... ORDERS; FRUITS, VEGETABLES, NUTS), DEPARTMENT OF AGRICULTURE HAZELNUTS GROWN IN OREGON AND WASHINGTON... according to size, internal quality, and external appearance and condition of hazelnuts packed in...

  3. Minimally packed phases in holography

    NASA Astrophysics Data System (ADS)

    Donos, Aristomenis; Gauntlett, Jerome P.

    2016-03-01

    We numerically construct asymptotically AdS black brane solutions of D = 4 Einstein-Maxwell theory coupled to a pseudoscalar. The solutions are holographically dual to d = 3 CFTs at finite chemical potential and in a constant magnetic field, which spontaneously break translation invariance leading to the spontaneous formation of abelian and momentum magnetisation currents flowing around the plaquettes of a periodic Bravais lattice. We analyse the three-dimensional moduli space of lattice solutions, which are generically oblique, and show, for a specific value of the magnetic field, that the free energy is minimised by the triangular lattice, associated with minimal packing of circles in the plane. We show that the average stress tensor for the thermodynamically preferred phase is that of a perfect fluid and that this result applies more generally to spontaneously generated periodic phases. The triangular structure persists at low temperatures indicating the existence of novel crystalline ground states.

  4. Confined disordered strictly jammed binary sphere packings

    NASA Astrophysics Data System (ADS)

    Chen, D.; Torquato, S.

    2015-12-01

    Disordered jammed packings under confinement have received considerably less attention than their bulk counterparts and yet arise in a variety of practical situations. In this work, we study binary sphere packings that are confined between two parallel hard planes and generalize the Torquato-Jiao (TJ) sequential linear programming algorithm [Phys. Rev. E 82, 061302 (2010), 10.1103/PhysRevE.82.061302] to obtain putative maximally random jammed (MRJ) packings that are exactly isostatic with high fidelity over a large range of plane separation distances H , small to large sphere radius ratio α , and small sphere relative concentration x . We find that packing characteristics can be substantially different from their bulk analogs, which is due to what we term "confinement frustration." Rattlers in confined packings are generally more prevalent than those in their bulk counterparts. We observe that packing fraction, rattler fraction, and degree of disorder of MRJ packings generally increase with H , though exceptions exist. Discontinuities in the packing characteristics as H varies in the vicinity of certain values of H are due to associated discontinuous transitions between different jammed states. When the plane separation distance is on the order of two large-sphere diameters or less, the packings exhibit salient two-dimensional features; when the plane separation distance exceeds about 30 large-sphere diameters, the packings approach three-dimensional bulk packings. As the size contrast increases (as α decreases), the rattler fraction dramatically increases due to what we call "size-disparity" frustration. We find that at intermediate α and when x is about 0.5 (50-50 mixture), the disorder of packings is maximized, as measured by an order metric ψ that is based on the number density fluctuations in the direction perpendicular to the hard walls. We also apply the local volume-fraction variance στ2(R ) to characterize confined packings and find that these

  5. 21 CFR 890.5700 - Cold pack.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Cold pack. 890.5700 Section 890.5700 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Therapeutic Devices § 890.5700 Cold pack. (a) Identification....

  6. 21 CFR 890.5700 - Cold pack.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Cold pack. 890.5700 Section 890.5700 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Therapeutic Devices § 890.5700 Cold pack. (a) Identification....

  7. 21 CFR 890.5700 - Cold pack.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Cold pack. 890.5700 Section 890.5700 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Therapeutic Devices § 890.5700 Cold pack. (a) Identification....

  8. 21 CFR 890.5700 - Cold pack.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Cold pack. 890.5700 Section 890.5700 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Therapeutic Devices § 890.5700 Cold pack. (a) Identification....

  9. Record high Wolf, Canis lupus, pack density

    USGS Publications Warehouse

    Mech, L.D.; Tracy, S.

    2004-01-01

    This report documents a year-around Wolf (Canis lupus) density of 18.2/100 km2 and a summer density of 30.8/100 km2, in a northeastern Minnesota Wolf pack. The previous record was a summer density of 14.1/100 km2, for a Wolf pack on Vancouver Island, British Columbia, Canada.

  10. Record high wolf, Canis lupus, pack density

    USGS Publications Warehouse

    Mech, L.D.; Tracy, S.

    2004-01-01

    This report documents a year-around wolf (Canis lupus) density of 18.2/100 m2 and summer density of 30.8/100 km2, in a northeastern Minnesota wolf pack. The previous record was a summer density of 14.1/100 km2, for a wolf pack on Vancouver Island, BC, Canada.

  11. Development of an effective valve packing program

    SciTech Connect

    Hart, K.A.

    1996-12-01

    Current data now shows that graphite valve packing installed within the guidance of a controlled program produces not only reliable stem sealing but predictable running loads. By utilizing recent technological developments in valve performance monitoring for both MOV`s and AOV`s, valve packing performance can be enhanced while reducing maintenance costs. Once known, values are established for acceptable valve packing loads, the measurement of actual valve running loads via the current MOV/AOV diagnostic techniques can provide indication of future valve stem sealing problems, improper valve packing installation or identify the opportunity for valve packing program improvements. At times the full benefit of these advances in material and predictive technology remain under utilized due to simple past misconceptions associated with valve packing. This paper will explore the basis for these misconceptions, provide general insight into the current understanding of valve packing and demonstrate how with this new understanding and current valve diagnostic equipment the key aspects required to develop an effective, quality valve packing program fit together. The cost and operational benefits provided by this approach can be significant impact by the: elimination of periodic valve repacking, reduction of maintenance costs, benefits of leak-free valve operation, justification for reduced Post Maintenance Test Requirements, reduced radiation exposure, improved plant appearance.

  12. 21 CFR 890.5700 - Cold pack.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Cold pack. 890.5700 Section 890.5700 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Therapeutic Devices § 890.5700 Cold pack. (a) Identification....

  13. Pack rats (Neotoma spp.): Keystone ecological engineers?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The potential role of two species of pack rats (Neotoma albigula and Neotoma micropus) as keystone ecological engineers was examined by estimating the species diversity of invertebrates living in the nest middens, and nitrogen mineralization rates in soils associated with the middens. Although pack-...

  14. Kid's PACK: Population Awareness Campaign Kit.

    ERIC Educational Resources Information Center

    Zero Population Growth, Inc., Washington, DC.

    This fun and educational kit is designed specifically for elementary students. The "Kid's PACK" (Population Awareness Campaign Kit) entertains and informs children on the environment and human population growth through stories, games, and concrete ideas for making a difference. In three booklets, the "Kid's PACK" offers elementary students…

  15. Method of gravel packing a well

    SciTech Connect

    Almond, S. W.; Himes, R. E.

    1985-11-12

    The present invention relates to a thermally stable crosslinked gel gravel packing fluid for use in the treatment of highly deviated well bores penetrating a subterranean formation. The gravel packing fluid comprises an aqueous liquid, a gelling agent comprising a selected modified cellulose ether, a crosslinking agent, a breaker, a particulate agent and any additional additives that may be present.

  16. Pack Density Limitations of Hybrid Parachutes

    NASA Technical Reports Server (NTRS)

    Zwicker, Matthew L.; Sinclair, Robert J.

    2013-01-01

    The development and testing of the Orion crew capsule parachute system has provided a unique opportunity to study dense parachute packing techniques and limits, in order to establish a new baseline for future programs. The density of parachute packs has a significant influence on vibration loads, retention system stresses, and parachute mortar performance. Material compositions and pack densities of existing designs for space capsule recovery were compared, using the pack density of the Apollo main parachutes as the current baseline. The composition of parachutes has changed since Apollo, incorporating new materials such as Kevlar , Vectran , Teflon and Spectra . These materials have different specific densities than Nylon, so the densities of hybrid parachute packs cannot be directly compared to Nylon parachutes for determination of feasibility or volume allocation. Six parachute packs were evaluated in terms of weighted average solid density in order to achieve a non-dimensional comparison of packing density. Means of mitigating damage due to packing pressure and mortar firing were examined in light of the Capsule Parachute Assembly System (CPAS) and Apollo experience. Parachute design improvements including incorporation of modern materials and manufacturing processes serves to make CPAS the new knowledge base on which future spacecraft parachute systems will be built.

  17. New value packing technology extends service life

    SciTech Connect

    Miller, M.; Jackson, R. )

    1993-10-01

    New packing techniques can extend packing life and retain low stem leakage. The HPI can use these designs to avoid mandatory monitoring and repair schedules for valves that exceed the 500-ppm emission threshold. New EPA leakage limits will enforce monitoring and maintenance programs if more than 2% of the facility's valves exceed this limit. Because valves are dynamic, their control actions are prone to leakage. Also, the best fire-resistant packing material, graphite, has inherent deficiencies such as high compression stress and a high-friction coefficient that shortens its service life. Four basic principles overcome graphite packing's shortcomings for control valve applications. Examples show how these criteria improve sliding stem and rotary valve performance. Incorporating these principles into valve-packing designs can ensure long, low-maintenance service life, and the added benefit of low leakage. Graphite is a very important packing material for the HPI. Unlike fluoropolymer (e.g., PTFE) packing, graphite can tolerate high process temperature without decomposing or losing its sealing properties. More importantly, graphite packing is fire safe. It can survive a fire without a catastrophic failure that could add more flammable materials.

  18. Probe with integrated heater and thermocouple pack

    SciTech Connect

    McCulloch, R.W.; Dial, R.E.; Finnell, W.F.R.

    1988-02-16

    This patent describes a gamma thermometer probe for detecting heat produced within the thermometer probe. It comprises: an outer elongate thermometer sheath; an elongate rod; annular recesses; a longitudinal bore; and an integrated thermocouple pack. The thermocouple pack comprises: a first type wire, and second type wires. The second type wires comprises: an outer section; and an inner segment.

  19. Coalescence preference in densely packed microbubbles

    SciTech Connect

    Kim, Yeseul; Lim, Su Jin; Gim, Bopil; Weon, Byung Mook

    2015-01-13

    A bubble merged from two parent bubbles with different size tends to be placed closer to the larger parent. This phenomenon is known as the coalescence preference. Here we demonstrate that the coalescence preference can be blocked inside a densely packed cluster of bubbles. We utilized high-speed high-resolution X-ray microscopy to clearly visualize individual coalescence events inside densely packed microbubbles with a local packing fraction of ~40%. Thus, the surface energy release theory predicts an exponent of 5 in a relation between the relative coalescence position and the parent size ratio, whereas our observation for coalescence in densely packed microbubbles shows a different exponent of 2. We believe that this result would be important to understand the reality of coalescence dynamics in a variety of packing situations of soft matter.

  20. Coalescence preference in densely packed microbubbles

    DOE PAGESBeta

    Kim, Yeseul; Lim, Su Jin; Gim, Bopil; Weon, Byung Mook

    2015-01-13

    A bubble merged from two parent bubbles with different size tends to be placed closer to the larger parent. This phenomenon is known as the coalescence preference. Here we demonstrate that the coalescence preference can be blocked inside a densely packed cluster of bubbles. We utilized high-speed high-resolution X-ray microscopy to clearly visualize individual coalescence events inside densely packed microbubbles with a local packing fraction of ~40%. Thus, the surface energy release theory predicts an exponent of 5 in a relation between the relative coalescence position and the parent size ratio, whereas our observation for coalescence in densely packed microbubblesmore » shows a different exponent of 2. We believe that this result would be important to understand the reality of coalescence dynamics in a variety of packing situations of soft matter.« less

  1. Coalescence preference in densely packed microbubbles

    PubMed Central

    Kim, Yeseul; Lim, Su Jin; Gim, Bopil; Weon, Byung Mook

    2015-01-01

    A bubble merged from two parent bubbles with different size tends to be placed closer to the larger parent. This phenomenon is known as the coalescence preference. Here we demonstrate that the coalescence preference can be blocked inside a densely packed cluster of bubbles. We utilized high-speed high-resolution X-ray microscopy to clearly visualize individual coalescence events inside densely packed microbubbles with a local packing fraction of ~40%. The surface energy release theory predicts an exponent of 5 in a relation between the relative coalescence position and the parent size ratio, whereas our observation for coalescence in densely packed microbubbles shows a different exponent of 2. We believe that this result would be important to understand the reality of coalescence dynamics in a variety of packing situations of soft matter. PMID:25583640

  2. Condensation in Nanoporous Packed Beds.

    PubMed

    Ally, Javed; Molla, Shahnawaz; Mostowfi, Farshid

    2016-05-10

    In materials with tiny, nanometer-scale pores, liquid condensation is shifted from the bulk saturation pressure observed at larger scales. This effect is called capillary condensation and can block pores, which has major consequences in hydrocarbon production, as well as in fuel cells, catalysis, and powder adhesion. In this study, high pressure nanofluidic condensation studies are performed using propane and carbon dioxide in a colloidal crystal packed bed. Direct visualization allows the extent of condensation to be observed, as well as inference of the pore geometry from Bragg diffraction. We show experimentally that capillary condensation depends on pore geometry and wettability because these factors determine the shape of the menisci that coalesce when pore filling occurs, contrary to the typical assumption that all pore structures can be modeled as cylindrical and perfectly wetting. We also observe capillary condensation at higher pressures than has been done previously, which is important because many applications involving this phenomenon occur well above atmospheric pressure, and there is little, if any, experimental validation of capillary condensation at such pressures, particularly with direct visualization. PMID:27115446

  3. Electromechanics of packed granular beds

    SciTech Connect

    Robinson, K.S.

    1982-01-01

    Strong, electrical, interparticle forces are induced by applied electric fields within packed beds of dielectric particles. Proposed applications utilizing electropacked beds (EPBs) or electrofluidized beds (EFBs) include air filtration and gas clean-up, fine particle separation, commercial drying and coating processes, heat and mass transfer, and bulk bed control. A new distributed circuit model of the electrical interparticle force is presented that identifies the role of surface roughness as determining the interparticle spacing. The dc steady state force is predicted to increase nearly linearly with the applied electric field and is theoretically independent of particle surface conductivity. The electric stress is found to vary nearly linearly with the applied electric field. Data are generally consistent with the theoretical contention that increased surface roughness decreases electromechanical effects. Surface conductivity variations of three to four times have no measurable effect on the dc steady state electric stress. The electric stress is insensitive to the dielectric properties of the interstitial gas eliminating Townsend discharge as a candidate for the nonlinear charge transport process thought to occur near interparticle contacts. The theoretical upper bound of the electric stress calculated using the distributed circuit model falls within the scatter of the data if a limit on the electric field in the interparticle gap which models nonlinear charge transport is in the range of 1 to 6 x 10/sup 7/ V/m. Estimates of the charge relaxation time using transient angle of repose experiments are somewhat smaller but comparable with theoretical values calculated by ignoring nonlinear charge transport.

  4. Diacetylmorphine (heroin) body packer presenting with respiratory arrest.

    PubMed

    Naseem, Arshad; Abbas, Shahid

    2009-04-01

    Intracorporeal concealment of illicit drugs known as 'body packing' is uncommonly reported. A body packer with swallowed capsules containing Diacetylmorphine (heroin) for smuggling purposes presented with respiratory arrest and recovered after ventilatory support and nalaxone infusion. PMID:19356347

  5. Jamming and crystallization in athermal polymer packings

    NASA Astrophysics Data System (ADS)

    Karayiannis, Nikos Ch.; Foteinopoulou, Katerina; Laso, Manuel

    2013-11-01

    Dense packings of chains of hard spheres possess characteristic features that do not have a counterpart in corresponding packings of monomeric spheres especially near the maximally random jammed (MRJ) state. From the modelling perspective the additional requirement that spheres keep their connectivity while maximizing the occupied volume fraction imposes severe constraints on generation algorithms of dense chain configurations. The extremely sluggish dynamics imposed by the uncrossability of chains precludes the use of deterministic or stochastic dynamics to generate all but dilute polymer packings. As a viable alternative, especially tailored chain-connectivity-altering Monte Carlo (MC) algorithms have been developed that bypass this kinetic hindrance and have actually been able to produce packings of hard-sphere chains in a volume fraction range spanning from infinite dilution up to the MRJ state. Such very dense athermal polymer packings share a number of structural features with packings of monomeric hard spheres, but also display unique characteristics due to the constraints imposed by connectivity. We give an overview of the most relevant results of our recent modeling work on packings of freely-jointed chains of tangent hard spheres about the MRJ state, local structure, chain dimensions and their scaling with density, topological constraints in the form of entanglements and knots, contact network at jamming, and entropically driven crystallization.

  6. Using colloidal packings as templates for structuring drugs

    NASA Astrophysics Data System (ADS)

    Wilking, James; Studart, André.; Koltzenburg, Sebastian; Guerra, Rodrigo; Amstad, Esther; Rieger, Jens; Weitz, David

    2012-02-01

    Many pharmaceutical compounds are poorly soluble in water; this is problematic because most pharmaceuticals are delivered orally and must dissolve in the gastrointestinal fluid in order to be taken up by the body. We introduce a simple method for increasing the dissolution rates of poorly water-soluble organic actives. We demonstrate that by structuring the compounds within the interconnected, nanoscale pore space of a colloidal packing we create composites which rapidly disintegrate in water, exposing the nanostructured organic active and leading to improved dissolution rates.

  7. Leadership in wolf, Canis lupus, packs

    USGS Publications Warehouse

    Mech, L.D.

    2000-01-01

    I examine leadership in Wolf (Canis lupus) packs based on published observations and data gathered during summers from 1986 to 1998 studying a free-ranging pack of Wolves on Ellesmere Island that were habituated to my presence. The breeding male tended to initiate activities associated with foraging and travel, and the breeding female to initiate, and predominate in, pup care and protection. However, there was considerable overlap and interaction during these activities such that leadership could be considered a joint function. In packs with multiple breeders, quantitative information about leadership is needed.

  8. Random sphere packing model of heterogeneous propellants

    NASA Astrophysics Data System (ADS)

    Kochevets, Sergei Victorovich

    It is well recognized that combustion of heterogeneous propellants is strongly dependent on the propellant morphology. Recent developments in computing systems make it possible to start three-dimensional modeling of heterogeneous propellant combustion. A key component of such large scale computations is a realistic model of industrial propellants which retains the true morphology---a goal never achieved before. The research presented develops the Random Sphere Packing Model of heterogeneous propellants and generates numerical samples of actual industrial propellants. This is done by developing a sphere packing algorithm which randomly packs a large number of spheres with a polydisperse size distribution within a rectangular domain. First, the packing code is developed, optimized for performance, and parallelized using the OpenMP shared memory architecture. Second, the morphology and packing fraction of two simple cases of unimodal and bimodal packs are investigated computationally and analytically. It is shown that both the Loose Random Packing and Dense Random Packing limits are not well defined and the growth rate of the spheres is identified as the key parameter controlling the efficiency of the packing. For a properly chosen growth rate, computational results are found to be in excellent agreement with experimental data. Third, two strategies are developed to define numerical samples of polydisperse heterogeneous propellants: the Deterministic Strategy and the Random Selection Strategy. Using these strategies, numerical samples of industrial propellants are generated. The packing fraction is investigated and it is shown that the experimental values of the packing fraction can be achieved computationally. It is strongly believed that this Random Sphere Packing Model of propellants is a major step forward in the realistic computational modeling of heterogeneous propellant of combustion. In addition, a method of analysis of the morphology of heterogeneous

  9. [Review: pathophysiology and methodology of nasal packing].

    PubMed

    Beule, A G; Weber, R K; Kaftan, H; Hosemann, W

    2004-08-01

    Nasal packing is a frequent procedure to control spontaneous nasal bleeding or postoperative oozing following different types of nasal surgery. It strives for internal stabilization of the nasal framework and for optimizing wound healing by prevention of stenosis or synechia. A lot of different materials is used and there is no accepted standard concerning the type and application. A review on pathophysiology of the packed nose is given together with a survey on customary packing materials focussing on the specific merits, demerits and side-effects including economical aspects. PMID:15316896

  10. Improved Taxation Rate for Bin Packing Games

    NASA Astrophysics Data System (ADS)

    Kern, Walter; Qiu, Xian

    A cooperative bin packing game is a N-person game, where the player set N consists of k bins of capacity 1 each and n items of sizes a 1, ⋯ ,a n . The value of a coalition of players is defined to be the maximum total size of items in the coalition that can be packed into the bins of the coalition. We present an alternative proof for the non-emptiness of the 1/3-core for all bin packing games and show how to improve this bound ɛ= 1/3 (slightly). We conjecture that the true best possible value is ɛ= 1/7.

  11. 7 CFR 51.3152 - Standard pack.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...) Nectarines packed in containers equipped with cell compartments, cardboard fillers or molded trays shall be... angles to a line from stem to blossom end of the fruit. (h) Tolerances. In order to allow for...

  12. 7 CFR 51.2338 - Standard pack.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... packed in containers with cell compartments, cardboard fillers or molded trays shall be of proper size... angles to a line from stem to blossom end. (f) In order to allow for variations incident to proper...

  13. 7 CFR 51.2338 - Standard pack.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... packed in containers with cell compartments, cardboard fillers or molded trays shall be of proper size... angles to a line from stem to blossom end. (f) In order to allow for variations incident to proper...

  14. 7 CFR 51.2338 - Standard pack.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    .... (c) Boxes, flats, lugs, or cartons: (1) Fruit packed in containers with cell compartments, cardboard...” means the greatest dimension measured at right angles to a line from stem to blossom end. (f) In...

  15. 7 CFR 51.2338 - Standard pack.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    .... (c) Boxes, flats, lugs, or cartons: (1) Fruit packed in containers with cell compartments, cardboard...” means the greatest dimension measured at right angles to a line from stem to blossom end. (f) In...

  16. 7 CFR 51.2338 - Standard pack.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... packed in containers with cell compartments, cardboard fillers or molded trays shall be of proper size... angles to a line from stem to blossom end. (f) In order to allow for variations incident to proper...

  17. 7 CFR 51.3152 - Standard pack.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...) Nectarines packed in containers equipped with cell compartments, cardboard fillers or molded trays shall be... angles to a line from stem to blossom end of the fruit. (h) Tolerances. In order to allow for...

  18. A Versatile, Automatic Chromatographic Column Packing Device

    ERIC Educational Resources Information Center

    Barry, Eugene F.; And Others

    1977-01-01

    Describes an inexpensive apparatus for packing liquid and gas chromatographic columns of high efficiency. Consists of stainless steel support struts, an Automat Getriebmotor, and an associated three-pulley system capable of 10, 30, and 300 rpm. (MLH)

  19. Mechanical Characterization of Partially Crystallized Sphere Packings

    NASA Astrophysics Data System (ADS)

    Hanifpour, M.; Francois, N.; Vaez Allaei, S. M.; Senden, T.; Saadatfar, M.

    2014-10-01

    We study grain-scale mechanical and geometrical features of partially crystallized packings of frictional spheres, produced experimentally by a vibrational protocol. By combining x-ray computed tomography, 3D image analysis, and discrete element method simulations, we have access to the 3D structure of internal forces. We investigate how the network of mechanical contacts and intergranular forces change when the packing structure evolves from amorphous to near perfect crystalline arrangements. We compare the behavior of the geometrical neighbors (quasicontracts) of a grain to the evolution of the mechanical contacts. The mechanical coordination number Zm is a key parameter characterizing the crystallization onset. The high fluctuation level of Zm and of the force distribution in highly crystallized packings reveals that a geometrically ordered structure still possesses a highly random mechanical backbone similar to that of amorphous packings.

  20. Think Safety When Picking, Packing School Backpacks

    MedlinePlus

    ... 160523.html Think Safety When Picking, Packing School Backpacks Heavy, unbalanced loads can cause injury that is ... Aug. 19, 2016 (HealthDay News) -- Many students use backpacks to carry their school books and supplies, but ...

  1. Groundwater well with reactive filter pack

    DOEpatents

    Gilmore, T.J.; Holdren, G.R. Jr.; Kaplan, D.I.

    1998-09-08

    A method and apparatus are disclosed for the remediation of contaminated soil and ground water wherein a reactive pack material is added to the annular fill material utilized in standard well construction techniques. 3 figs.

  2. Groundwater well with reactive filter pack

    DOEpatents

    Gilmore, Tyler J.; Holdren, Jr., George R.; Kaplan, Daniel I.

    1998-01-01

    A method and apparatus for the remediation of contaminated soil and ground water wherein a reactive pack material is added to the annular fill material utilized in standard well construction techniques.

  3. Packing and Entanglements in Polymer Melts

    NASA Astrophysics Data System (ADS)

    Ozisik, Rahmi; Sternstein, Sandy S.

    2004-03-01

    The idea of obtaining the properties of polymers simply from the chemical structure is a very attractive one. Recent work on entanglements and packing indicates that the entanglement molecular weight is related to packing length (= M/(ρ N_a), where M is the molecular weight, ρ is the density, R is the end-to-end vector, and Na is the Avogadro number). The exact relationship is given as follows: Me = 218 ρ p^3. This simple equation holds for a very large group of polymers and is temperature insensitive. In this study, we studied the packing and tried to obtain a scaling between packing and M_e, and extended the concept to cyclic polymers.

  4. Contact breaking in frictionless granular packings

    NASA Astrophysics Data System (ADS)

    Wu, Qikai; Bertrand, Thibault; O'Hern, Corey; Shattuck, Mark

    We numerically study the breaking of interparticle contact networks in static granular packings of frictionless bidisperse disks that are subjected to vibrations. The packings are created using an isotropic compression protocol at different values of the total potential energy per particle Ep. We first add displacements along a single vibrational mode i of the dynamical matrix to a given packing and calculate the minimum amplitude Ai of the perturbation at which the first interparticle contact breaks. We then identify the minimum amplitude Amin over all perturbations along each mode and study the distribution of Amin from an ensemble of packings at each Ep. We then study two-, three-, and multi-mode excitations and determine the dependence of Amin on the number of modes that are included in the perturbation. W. M. Keck Foundation Science and Engineering Grant.

  5. Software For Nearly Optimal Packing Of Cargo

    NASA Technical Reports Server (NTRS)

    Fennel, Theron R.; Daughtrey, Rodney S.; Schwaab, Doug G.

    1994-01-01

    PACKMAN computer program used to find nearly optimal arrangements of cargo items in storage containers, subject to such multiple packing objectives as utilization of volumes of containers, utilization of containers up to limits on weights, and other considerations. Automatic packing algorithm employed attempts to find best positioning of cargo items in container, such that volume and weight capacity of container both utilized to maximum extent possible. Written in Common LISP.

  6. Modular vaccine packaging increases packing efficiency

    PubMed Central

    Norman, Bryan A.; Rajgopal, Jayant; Lim, Jung; Gorham, Katrin; Haidari, Leila; Brown, Shawn T.; Lee, Bruce Y.

    2015-01-01

    Background Within a typical vaccine supply chain, vaccines are packaged into individual cylindrical vials (each containing one or more doses) that are bundled together in rectangular “inner packs” for transport via even larger groupings such as cold boxes and vaccine carriers. The variability of vaccine inner pack and vial size may hinder efficient vaccine distribution because it constrains packing of cold boxes and vaccine carriers to quantities that are often inappropriate or suboptimal in the context of country-specific vaccination guidelines. Methods We developed in Microsoft Excel (Microsoft Corp., Redmond, WA) a spreadsheet model that evaluated the impact of different packing schemes for the Benin routine regimen plus the introduction of the Rotarix vaccine. Specifically, we used the model to compare the current packing scheme to that of a proposed modular packing scheme. Results Conventional packing of a Dometic RCW25 that aims to maximize fully-immunized children (FICs) results in 123 FICs and a packing efficiency of 81.93% compared to a maximum of 155 FICs and 94.1% efficiency for an alternative modular packaging system. Conclusions Our analysis suggests that modular packaging systems could offer significant advantages over conventional vaccine packaging systems with respect to space efficiency and potential FICs, when they are stored in standard vaccine carrying devices. This allows for more vaccines to be stored within the same volume while also simplifying the procedures used by field workers to pack storage devices. Ultimately, modular packaging systems could be a simple way to help increase vaccine coverage worldwide. PMID:25957666

  7. Pharyngeal Packing during Rhinoplasty: Advantages and Disadvantages

    PubMed Central

    Razavi, Majid; Taghavi Gilani, Mehryar; Bameshki, Ali Reza; Behdani, Reza; Khadivi, Ehsan; Bakhshaee, Mahdi

    2015-01-01

    Introduction: Controversy remains as to the advantages and disadvantages of pharyngeal packing during septorhinoplasty. Our study investigated the effect of pharyngeal packing on postoperative nausea and vomiting and sore throat following this type of surgery or septorhinoplasty. Materials and Methods: This clinical trial was performed on 90 American Society of Anesthesiologists (ASA) I or II patients who were candidates for septorhinoplasty. They were randomly divided into two groups. Patients in the study group had received pharyngeal packing while those in the control group had not. The incidence of nausea and vomiting and sore throat based on the visual analog scale (VAS) was evaluated postoperatively in the recovery room as well as at 2, 6 and 24 hours. Results: The incidence of postoperative nausea and vomiting (PONV) was 12.3%, with no significant difference between the study and control groups. Sore throat was reported in 50.5% of cases overall (56.8% on pack group and 44.4% on control). Although the severity of pain was higher in the study group at all times, the incidence in the two groups did not differ significantly. Conclusion: The use of pharyngeal packing has no effect in reducing the incidence of nausea and vomiting and sore throat after surgery. Given that induced hypotension is used as the routine method of anesthesia in septorhinoplasty surgery, with a low incidence of hemorrhage and a high risk of unintended retention of pharyngeal packing, its routine use is not recommended for this procedure. PMID:26788486

  8. Packing of elastic wires in flexible shells

    NASA Astrophysics Data System (ADS)

    Vetter, R.; Wittel, F. K.; Herrmann, H. J.

    2015-11-01

    The packing problem of long thin filaments that are injected into confined spaces is of fundamental interest for physicists and biologists alike. How linear threads pack and coil is well known only for the ideal case of rigid containers, though. Here, we force long elastic rods into flexible spatial confinement borne by an elastic shell to examine under which conditions recently acquired knowledge on wire packing in rigid spheres breaks down. We find that unlike in rigid cavities, friction plays a key role by giving rise to the emergence of two distinct packing patterns. At low friction, the wire densely coils into an ordered toroidal bundle with semi-ellipsoidal cross-section, while at high friction, it packs into a highly disordered, hierarchic structure. These two morphologies are shown to be separated by a continuous phase transition. Our findings demonstrate the dramatic impact of friction and confinement elasticity on filamentous packing and might drive future research on such systems in physics, biology and even medical technology toward including these mutually interacting effects.

  9. Bidispersed Sphere Packing on Spherical Surfaces

    NASA Astrophysics Data System (ADS)

    Atherton, Timothy; Mascioli, Andrew; Burke, Christopher

    Packing problems on spherical surfaces have a long history, originating in the classic Thompson problem of finding the ground state configuration of charges on a sphere. Such packings contain a minimal number of defects needed to accommodate the curvature; this is predictable using the Gauss-Bonnet theorem from knowledge of the topology of the surface and the local symmetry of the ordering. Famously, the packing of spherical particles on a sphere contains a 'scar' transition, where additional defects over those required by topology appear above a certain critical number of particles and self-organize into chains or scars. In this work, we study the packing of bidispersed packings on a sphere, and hence determine the interaction of bidispersity and curvature. The resultant configurations are nearly crystalline for low values of bidispersity and retain scar-like structures; these rapidly become disordered for intermediate values and approach a so-called Appollonian limit at the point where smaller particles can be entirely accommodated within the voids left by the larger particles. We connect our results with studies of bidispersed packings in the bulk and on flat surfaces from the literature on glassy systems and jamming. Supported by a Cottrell Award from the Research Corporation for Science Advancement.

  10. Decontamination of pesticide packing using ionizing radiation

    NASA Astrophysics Data System (ADS)

    Duarte, C. L.; Mori, M. N.; Kodama, Yasko; Oikawa, H.; Sampa, M. H. O.

    2007-11-01

    The Brazilian agriculture activities have consumed about 288,000 tons of pesticides per year conditioned in about 107,000,000 packing with weight of approximately 23,000 tons. The discharge of empty plastic packing of pesticides can be an environmental concern causing problems to human health, animals, and plants if done without inspection and monitoring. The objective of this work is to study the ionizing radiation effect in the main pesticides used in Brazil for plastic packing decontamination. Among the commercial pesticides, chlorpyrifos has significant importance because of its wide distribution and extensive use and persistence. The radiation-induced degradation of chlorpyrifos in liquid samples and in polyethylene pack was studied by gamma radiolysis. Packing of high-density polyethylene (HDPE) three layer coextruded, named COEX, contaminated with chlorpyrifos, were irradiated using both a multipurpose Co-60 gamma irradiator and a gamma source with 5000 Ci total activity Gamma cell type. The chemical analysis of the chlorpyrifos was made using a gas chromatography associated to the Mass Spectrometry—GCMS from Shimadzu Model QP 5000. Gamma radiation was efficient for removing chlorpyrifos from the plastic packing, in all studied cases.

  11. Snow Pack and Lake Ice Pack Remote Sensing using Wideband Autocorrelation Radiometry

    NASA Astrophysics Data System (ADS)

    Mousavi, S.; De Roo, R. D.; Sarabandi, K.; England, A. W.

    2015-12-01

    A novel microwave radiometric technique, wideband autocorrelation radiometry (WiBAR), offers a deterministic method of remotely sensing the propagation time τdelay of microwaves through low loss layers at the bottom of the atmosphere. Terrestrial examples are the snow and lake ice packs. This technique is based on the Planck radiation from the surface beneath the pack which travels upwards through the pack towards the radiometer; such a signal we call a direct signal. On the other hand, part of this radiation reflects back from the pack's upper interface then from its lower interface, before traveling towards the radiometer's antenna. Thus, there are two signals received by the radiometer, the direct signal and a delayed copy of it. The microwave propagation time τdelay through the pack yields a measure of its vertical extent. We report a time series of measurements of the ice pack on Lake Superior from February to April 2014 to demonstrate this technique. The observations are done at frequencies from 7 to 10 GHz. At these frequencies, the volume and surface scattering are small in the ice pack. This technique is inherently low-power since there is no transmitter as opposed to active remote sensing techniques. The results of this paper is to present the WiBAR technique and show that the microwave travel time within a dry snow pack and lake ice pack can be deterministically measured for different thicknesses using this technique.

  12. GravitinoPack and decays of supersymmetric metastable particles

    NASA Astrophysics Data System (ADS)

    Eberl, Helmut; Spanos, Vassilis C.

    2016-05-01

    We present the package GravitinoPack that calculates the two- and three-body decays of unstable supersymmetric particles involving the gravitino in the final or initial state. In a previous paper, we already showed results for the gravitino decaying into two and three particles. In this paper, we incorporate the processes where an unstable neutralino, stau or stop decays into a gravitino and Standard Model particles. This is the case in gravitino dark matter supersymmetric models, where the gravitino is the lightest SUSY particle. We give instructions for the installation and the use of the package. In the numerical analysis, we discuss various MSSM scenarios. We show that the calculation of all the decay channels and the three-body decay branching ratios is essential for the accurate application of cosmological bounds on these models.

  13. Hard convex lens-shaped particles: Densest-known packings and phase behavior

    NASA Astrophysics Data System (ADS)

    Cinacchi, Giorgio; Torquato, Salvatore

    2015-12-01

    By using theoretical methods and Monte Carlo simulations, this work investigates dense ordered packings and equilibrium phase behavior (from the low-density isotropic fluid regime to the high-density crystalline solid regime) of monodisperse systems of hard convex lens-shaped particles as defined by the volume common to two intersecting congruent spheres. We show that, while the overall similarity of their shape to that of hard oblate ellipsoids is reflected in a qualitatively similar phase diagram, differences are more pronounced in the high-density crystal phase up to the densest-known packings determined here. In contrast to those non-(Bravais)-lattice two-particle basis crystals that are the densest-known packings of hard (oblate) ellipsoids, hard convex lens-shaped particles pack more densely in two types of degenerate crystalline structures: (i) non-(Bravais)-lattice two-particle basis body-centered-orthorhombic-like crystals and (ii) (Bravais) lattice monoclinic crystals. By stacking at will, regularly or irregularly, laminae of these two crystals, infinitely degenerate, generally non-periodic in the stacking direction, dense packings can be constructed that are consistent with recent organizing principles. While deferring the assessment of which of these dense ordered structures is thermodynamically stable in the high-density crystalline solid regime, the degeneracy of their densest-known packings strongly suggests that colloidal convex lens-shaped particles could be better glass formers than colloidal spheres because of the additional rotational degrees of freedom.

  14. Hard convex lens-shaped particles: Densest-known packings and phase behavior

    SciTech Connect

    Cinacchi, Giorgio; Torquato, Salvatore

    2015-12-14

    By using theoretical methods and Monte Carlo simulations, this work investigates dense ordered packings and equilibrium phase behavior (from the low-density isotropic fluid regime to the high-density crystalline solid regime) of monodisperse systems of hard convex lens-shaped particles as defined by the volume common to two intersecting congruent spheres. We show that, while the overall similarity of their shape to that of hard oblate ellipsoids is reflected in a qualitatively similar phase diagram, differences are more pronounced in the high-density crystal phase up to the densest-known packings determined here. In contrast to those non-(Bravais)-lattice two-particle basis crystals that are the densest-known packings of hard (oblate) ellipsoids, hard convex lens-shaped particles pack more densely in two types of degenerate crystalline structures: (i) non-(Bravais)-lattice two-particle basis body-centered-orthorhombic-like crystals and (ii) (Bravais) lattice monoclinic crystals. By stacking at will, regularly or irregularly, laminae of these two crystals, infinitely degenerate, generally non-periodic in the stacking direction, dense packings can be constructed that are consistent with recent organizing principles. While deferring the assessment of which of these dense ordered structures is thermodynamically stable in the high-density crystalline solid regime, the degeneracy of their densest-known packings strongly suggests that colloidal convex lens-shaped particles could be better glass formers than colloidal spheres because of the additional rotational degrees of freedom.

  15. 21 CFR 880.5760 - Chemical cold pack snakebite kit.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Chemical cold pack snakebite kit. 880.5760 Section... Therapeutic Devices § 880.5760 Chemical cold pack snakebite kit. (a) Identification. A chemical cold pack snakebit kit is a device consisting of a chemical cold pack and tourniquet used for first-aid treatment...

  16. 21 CFR 880.5760 - Chemical cold pack snakebite kit.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Chemical cold pack snakebite kit. 880.5760 Section... Therapeutic Devices § 880.5760 Chemical cold pack snakebite kit. (a) Identification. A chemical cold pack snakebit kit is a device consisting of a chemical cold pack and tourniquet used for first-aid treatment...

  17. Quasistatic packings of droplets in flat microfluidic channels

    NASA Astrophysics Data System (ADS)

    Kadivar, Erfan

    2016-02-01

    As observed in recent experiments, monodisperse droplets self-assemble spontaneously in different ordered packings. In this work, we present a numerical study of the droplet packings in the flat rectangular microfluidic channels. Employing the boundary element method, we numerically solve the Stokes equation in two-dimension and investigate the appearance of droplet packing and transition between one and two-row packings of monodisperse emulsion droplets. By calculating packing force applied on the droplet interface, we investigate the effect of flow rate, droplet size, and surface tension on the packing configurations of droplets and transition between different topological packings.

  18. Coalescence preference in dense packing of bubbles

    NASA Astrophysics Data System (ADS)

    Kim, Yeseul; Gim, Bopil; Gim, Bopil; Weon, Byung Mook

    2015-11-01

    Coalescence preference is the tendency that a merged bubble from the contact of two original bubbles (parent) tends to be near to the bigger parent. Here, we show that the coalescence preference can be blocked by densely packing of neighbor bubbles. We use high-speed high-resolution X-ray microscopy to clearly visualize individual coalescence phenomenon which occurs in micro scale seconds and inside dense packing of microbubbles with a local packing fraction of ~40%. Previous theory and experimental evidence predict a power of -5 between the relative coalescence position and the parent size. However, our new observation for coalescence preference in densely packed microbubbles shows a different power of -2. We believe that this result may be important to understand coalescence dynamics in dense packing of soft matter. This work (NRF-2013R1A22A04008115) was supported by Mid-career Researcher Program through NRF grant funded by the MEST and also was supported by Ministry of Science, ICT and Future Planning (2009-0082580) and by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry and Education, Science and Technology (NRF-2012R1A6A3A04039257).

  19. Suicide of a body packer.

    PubMed

    Stichenwirth, M; Stelwag-Carion, C; Klupp, N; Hönigschnabl, S; Vycudilik, W; Bauer, G; Risser, D

    2000-01-24

    The smuggling of illicit drugs by means of body packing has become a common problem at European airports. Europe is considered to be the fastest growing market for cocaine worldwide, and the air route is the most frequently used method of trafficking cocaine. Smuggling illicit drugs by use of body packing is considered to be a high toxicological hazard because of the risk of leakage or a package bursting. We report about the first case of suicide of a body packer by re-ingesting the content of excreted cocaine packages. The consequence of this case is that the death scene investigation and autopsy assessments in case of a body packer's death should always consider the possibility of re-ingested packages. Detention personnel should be instructed by forensic and criminalistic experts to take preventive measures. PMID:10697780

  20. Deterioration of organic packing materials commonly used in air biofiltration: effect of VOC-packing interactions.

    PubMed

    Lebrero, Raquel; Estrada, José M; Muñoz, Raúl; Quijano, Guillermo

    2014-05-01

    The abiotic deterioration of three conventional organic packing materials used in biofiltration (compost, wood bark and Macadamia nutshells) caused by their interaction with toluene (used as a model volatile organic compound) was here studied. The deterioration of the materials was evaluated in terms of structural damage, release of co-substrates and increase of the packing biodegradability. After 21 days of exposure to toluene, all packing materials released co-substrates able to support microbial growth, which were not released by the control materials not exposed to toluene. Likewise, the exposure to toluene increased the packing material biodegradability by 26% in wood bark, 20% in compost and 17% in Macadamia nutshells. Finally, scanning electron microscopy analysis confirmed the deterioration in the structure of the packing materials evaluated due to the exposure to toluene, Macadamia nutshells being the material with the highest resistance to volatile organic compound attack. PMID:24603032

  1. GraSPI (Graphical Structured Packing Interface)

    Energy Science and Technology Software Center (ESTSC)

    2004-06-10

    GraSPI is a collection of macros (computer programs) written to work in concert with Fluent Inc. software GAMBIT and FLUENT for modeling and design of structured packing columns used in the chemical industry (the application focus is in distillation but other applications such as gas absorbers, and other chemical contactors can also be analyzed). GraSPI is an accessory to GAMBIT and FLUENT that drives the process of complex geometry creation, domain setup, and mesh generation.more » In addition, GraSPI manages automatic flow analysis in the aforementioned domain via either serial or parallel computing using FLUENT. A library of typical commercial structured packing elements is included in GraSPI, so is the capability for user-defined creation of new packings.« less

  2. Method for packed column separations and purifications

    DOEpatents

    Holman, David A.; Bruckner-Lea, Cynthia J.; Brockman, Fred J.; Chandler, Darrell P.

    2006-08-15

    The invention encompasses a method of packing and unpacking a column chamber. A mixture of a fluid and a matrix material are introduced through a column chamber inlet so that the matrix material is packed within a column chamber to form a packed column. The column chamber having the column chamber inlet or first port for receiving the mixture further has an outlet port and an actuator port. The outlet port is partially closed for capturing the matrix material and permitting the fluid to flow therepast by rotating relative one to the other of a rod placed in the actuator port. Further rotation relative one to the other of the rod and the column chamber opens the outlet and permits the matrix material and the fluid to flow therethrough thereby unpacking the matrix material from the column chamber.

  3. Spontaneous Crystallization in Athermal Polymer Packings

    PubMed Central

    Karayiannis, Nikos Ch.; Foteinopoulou, Katerina; Laso, Manuel

    2013-01-01

    We review recent results from extensive simulations of the crystallization of athermal polymer packings. It is shown that above a certain packing density, and for sufficiently long simulations, all random assemblies of freely-jointed chains of tangent hard spheres of uniform size show a spontaneous transition into a crystalline phase. These polymer crystals adopt predominantly random hexagonal close packed morphologies. An analysis of the local environment around monomers based on the shape and size of the Voronoi polyhedra clearly shows that Voronoi cells become more spherical and more symmetric as the system transits to the ordered state. The change in the local environment leads to an increase in the monomer translational contribution to the entropy of the system, which acts as the driving force for the phase transition. A comparison of the crystallization of hard-sphere polymers and monomers highlights similarities and differences resulting from the constraints imposed by chain connectivity. PMID:23263666

  4. Safety considerations for fabricating lithium battery packs

    NASA Technical Reports Server (NTRS)

    Ciesla, J. J.

    1986-01-01

    Lithium cell safety is a major issue with both manufacturers and end users. Most manufacturers have taken great strides to develop the safest cells possible while still maintaining performance characteristics. The combining of lithium cells for higher voltages, currents, and capacities requires the fabricator of lithium battery packs to be knowledgable about the specific electrochemical system being used. Relatively high rate, spirally wound (large surface area) sulfur oxychloride cells systems, such as Li/Thionyl or Sulfuryl chloride are considered. Prior to the start of a design of a battery pack, a review of the characterization studies for the cells should be conducted. The approach for fabricating a battery pack might vary with cell size.

  5. Mathematical Simulation of the Structural Properties of Packed and Fluidized Beds

    NASA Astrophysics Data System (ADS)

    Fedorov, S. S.; Gubinskii, M. V.; Foris', S. N.

    2016-05-01

    Based on the algorithm of successive filling a given volume with single spheres, a mathematical model of random packing of a limited volume of a bed in the field of body forces has been developed. This model can be applied to electrothermal packed- and fluidized-bed furnaces and will make it possible to investigate the thermal and electrical conductivity of such beds. A check of the adequacy of the model showed its correspondence to the well-known experimental and calculated results, as well as the stability of the solutions obtained with its aid.

  6. Mathematical Simulation of the Structural Properties of Packed and Fluidized Beds

    NASA Astrophysics Data System (ADS)

    Fedorov, S. S.; Gubinskii, M. V.; Foris', S. N.

    2016-06-01

    Based on the algorithm of successive filling a given volume with single spheres, a mathematical model of random packing of a limited volume of a bed in the field of body forces has been developed. This model can be applied to electrothermal packed- and fluidized-bed furnaces and will make it possible to investigate the thermal and electrical conductivity of such beds. A check of the adequacy of the model showed its correspondence to the well-known experimental and calculated results, as well as the stability of the solutions obtained with its aid.

  7. Dense packing: surgical indications and technical considerations.

    PubMed

    Farjo, Bessam; Farjo, Nilofer

    2013-08-01

    Dense packing is the philosophy of fitting more than 30 to 35 follicular unit grafts per square centimeter in one operation. The aim is to produce a more even, consistent, and natural looking flow of hair after just one procedure. Although desirable in principle, not all patients are suitable candidates nor is it possible to achieve in certain patients (eg, coarse or curly hair). Patients who have sufficient donor availability, reasonably stable hair loss, and high hair-to-skin color ratios are the ideal candidates. The authors highlight their philosophies and strategies for dense packing. PMID:24017984

  8. Case for mandatory reporting of 'body packers'.

    PubMed

    Mitra, Biswadev; Smit, De Villiers; O'Shea, William P

    2012-12-01

    Body packing is the term used to describe the ingestion of illicit substances for transport across control lines. Where the diagnosis of body packing is made independently in the ED, the issue of reporting the case to law enforcement officials poses a difficult scenario given the legal obligations of patient confidentiality. We describe a case of a body packer brought into the ED and subsequently reported to the police. The conflicts between patient confidentiality versus statutory exceptions to confidentiality along with case law regarding this scenario are discussed. PMID:23216730

  9. The benefits of using customized procedure packs.

    PubMed

    Baines, R; Colquhoun, G; Jones, N; Bateman, R

    2001-01-01

    Discrete item purchasing is the traditional approach for hospitals to obtain consumable supplies for theatre procedures. Although most items are relatively low cost, the management and co-ordination of the supply chain, raising orders, controlling stock, picking and delivering to each operating theatre can be complex and costly. Customized procedure packs provide a solution. PMID:11892113

  10. Random close packing in protein cores

    NASA Astrophysics Data System (ADS)

    Gaines, Jennifer C.; Smith, W. Wendell; Regan, Lynne; O'Hern, Corey S.

    2016-03-01

    Shortly after the determination of the first protein x-ray crystal structures, researchers analyzed their cores and reported packing fractions ϕ ≈0.75 , a value that is similar to close packing of equal-sized spheres. A limitation of these analyses was the use of extended atom models, rather than the more physically accurate explicit hydrogen model. The validity of the explicit hydrogen model was proved in our previous studies by its ability to predict the side chain dihedral angle distributions observed in proteins. In contrast, the extended atom model is not able to recapitulate the side chain dihedral angle distributions, and gives rise to large atomic clashes at side chain dihedral angle combinations that are highly probable in protein crystal structures. Here, we employ the explicit hydrogen model to calculate the packing fraction of the cores of over 200 high-resolution protein structures. We find that these protein cores have ϕ ≈0.56 , which is similar to results obtained from simulations of random packings of individual amino acids. This result provides a deeper understanding of the physical basis of protein structure that will enable predictions of the effects of amino acid mutations to protein cores and interfaces of known structure.

  11. Close packing of rods on spherical surfaces

    NASA Astrophysics Data System (ADS)

    Smallenburg, Frank; Löwen, Hartmut

    2016-04-01

    We study the optimal packing of short, hard spherocylinders confined to lie tangential to a spherical surface, using simulated annealing and molecular dynamics simulations. For clusters of up to twelve particles, we map out the changes in the geometry of the closest-packed configuration as a function of the aspect ratio L/D, where L is the cylinder length and D the diameter of the rods. We find a rich variety of cluster structures. For larger clusters, we find that the best-packed configurations up to around 100 particles are highly dependent on the exact number of particles and aspect ratio. For even larger clusters, we find largely disordered clusters for very short rods (L/D = 0.25), while slightly longer rods (L/D = 0.5 or 1) prefer a global baseball-like geometry of smectic-like domains, similar to the behavior of large-scale nematic shells. Intriguingly, we observe that when compared to their optimal flat-plane packing, short rods adapt to the spherical geometry more efficiently than both spheres and longer rods. Our results provide predictions for experimentally realizable systems of colloidal rods trapped at the interface of emulsion droplets.

  12. Close packing of rods on spherical surfaces.

    PubMed

    Smallenburg, Frank; Löwen, Hartmut

    2016-04-28

    We study the optimal packing of short, hard spherocylinders confined to lie tangential to a spherical surface, using simulated annealing and molecular dynamics simulations. For clusters of up to twelve particles, we map out the changes in the geometry of the closest-packed configuration as a function of the aspect ratio L/D, where L is the cylinder length and D the diameter of the rods. We find a rich variety of cluster structures. For larger clusters, we find that the best-packed configurations up to around 100 particles are highly dependent on the exact number of particles and aspect ratio. For even larger clusters, we find largely disordered clusters for very short rods (L/D = 0.25), while slightly longer rods (L/D = 0.5 or 1) prefer a global baseball-like geometry of smectic-like domains, similar to the behavior of large-scale nematic shells. Intriguingly, we observe that when compared to their optimal flat-plane packing, short rods adapt to the spherical geometry more efficiently than both spheres and longer rods. Our results provide predictions for experimentally realizable systems of colloidal rods trapped at the interface of emulsion droplets. PMID:27131565

  13. 7 CFR 989.9 - Packed raisins.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 8 2012-01-01 2012-01-01 false Packed raisins. 989.9 Section 989.9 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE RAISINS PRODUCED FROM GRAPES GROWN...

  14. 7 CFR 989.9 - Packed raisins.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Packed raisins. 989.9 Section 989.9 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE RAISINS PRODUCED FROM GRAPES GROWN...

  15. 7 CFR 989.9 - Packed raisins.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 8 2013-01-01 2013-01-01 false Packed raisins. 989.9 Section 989.9 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS AND ORDERS; FRUITS, VEGETABLES, NUTS), DEPARTMENT OF AGRICULTURE RAISINS PRODUCED FROM GRAPES GROWN...

  16. 7 CFR 989.9 - Packed raisins.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 8 2011-01-01 2011-01-01 false Packed raisins. 989.9 Section 989.9 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE RAISINS PRODUCED FROM GRAPES GROWN...

  17. 7 CFR 989.9 - Packed raisins.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 8 2014-01-01 2014-01-01 false Packed raisins. 989.9 Section 989.9 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS AND ORDERS; FRUITS, VEGETABLES, NUTS), DEPARTMENT OF AGRICULTURE RAISINS PRODUCED FROM GRAPES GROWN...

  18. 7 CFR 917.13 - Pack.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Pack. 917.13 Section 917.13 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE FRESH PEARS AND PEACHES GROWN IN...

  19. Packing frustration in dense confined fluids

    NASA Astrophysics Data System (ADS)

    Nygârd, Kim; Sarman, Sten; Kjellander, Roland

    2014-09-01

    Packing frustration for confined fluids, i.e., the incompatibility between the preferred packing of the fluid particles and the packing constraints imposed by the confining surfaces, is studied for a dense hard-sphere fluid confined between planar hard surfaces at short separations. The detailed mechanism for the frustration is investigated via an analysis of the anisotropic pair distributions of the confined fluid, as obtained from integral equation theory for inhomogeneous fluids at pair correlation level within the anisotropic Percus-Yevick approximation. By examining the mean forces that arise from interparticle collisions around the periphery of each particle in the slit, we calculate the principal components of the mean force for the density profile - each component being the sum of collisional forces on a particle's hemisphere facing either surface. The variations of these components with the slit width give rise to rather intricate changes in the layer structure between the surfaces, but, as shown in this paper, the basis of these variations can be easily understood qualitatively and often also semi-quantitatively. It is found that the ordering of the fluid is in essence governed locally by the packing constraints at each single solid-fluid interface. A simple superposition of forces due to the presence of each surface gives surprisingly good estimates of the density profiles, but there remain nontrivial confinement effects that cannot be explained by superposition, most notably the magnitude of the excess adsorption of particles in the slit relative to bulk.

  20. Characteristics of Stratified Bedded Pack Dairy Manure

    Technology Transfer Automated Retrieval System (TEKTRAN)

    "Compost" dairy barns are a relatively new housing system that generates a deep (0.9 to 1.5 m), stratified bedded pack (SBP) manure source. Bedding composed of sawdust, wood chips, or crop residues accumulates as additions are made to maintain a dry surface. Surface drying is promoted by a combinati...

  1. Porous bead packings for gas chromatography

    NASA Technical Reports Server (NTRS)

    Pollock, G. E.; Woeller, F. H.

    1979-01-01

    Porous polyaromatic packing beads have low polarity, high efficiency, short retention time, and may be synthesized in size range of 50 to 150 micrometers (100 to 270 mesh). Mechanically strong beads may be produced using various materials depending on elements and compounds to be identified.

  2. Simple Cloud Chambers Using Gel Ice Packs

    ERIC Educational Resources Information Center

    Kamata, Masahiro; Kubota, Miki

    2012-01-01

    Although cloud chambers are highly regarded as teaching aids for radiation education, school teachers have difficulty in using cloud chambers because they have to prepare dry ice or liquid nitrogen before the experiment. We developed a very simple and inexpensive cloud chamber that uses the contents of gel ice packs which can substitute for dry…

  3. Stuffed Derivatives of Close-Packed Structures

    ERIC Educational Resources Information Center

    Douglas, Bodie E.

    2007-01-01

    Decades ago Buerger described and later Palmer reviewed stuffed silica crystal structures widely used by mineralogists. Many publications and books have discussed common crystal structures in terms of close-packing of one set of atoms or ions (P sites) with other atoms or ions in tetrahedral (T) or octahedral (O) sites. Douglas and Ho described…

  4. PROTEIN RECOVERY FROM BEEF PACKING EFFLUENT

    EPA Science Inventory

    The wastewater from a beef packing plant contained 4,600 mg/1 COD and 2,500 mg/1 of suspended solids. A physiochemical wastewater treatment process that recovers protein removed 80% of the oxygen demand and suspended solids, and 94% of the fat, oil, and grease. Total cost was $3 ...

  5. 7 CFR 947.14 - Pack.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Pack. 947.14 Section 947.14 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE IRISH POTATOES GROWN IN MODOC AND...

  6. 7 CFR 947.14 - Pack.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 8 2011-01-01 2011-01-01 false Pack. 947.14 Section 947.14 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE IRISH POTATOES GROWN IN MODOC AND...

  7. 7 CFR 947.14 - Pack.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 8 2014-01-01 2014-01-01 false Pack. 947.14 Section 947.14 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS AND ORDERS; FRUITS, VEGETABLES, NUTS), DEPARTMENT OF AGRICULTURE IRISH POTATOES GROWN IN MODOC AND...

  8. 7 CFR 947.14 - Pack.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 8 2013-01-01 2013-01-01 false Pack. 947.14 Section 947.14 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS AND ORDERS; FRUITS, VEGETABLES, NUTS), DEPARTMENT OF AGRICULTURE IRISH POTATOES GROWN IN MODOC AND...

  9. 7 CFR 947.14 - Pack.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 8 2012-01-01 2012-01-01 false Pack. 947.14 Section 947.14 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE IRISH POTATOES GROWN IN MODOC AND...

  10. Packing morphology of wavy nanofiber arrays.

    PubMed

    Stein, Itai Y; Wardle, Brian L

    2016-01-14

    Existing theories for quantifying the morphology of nanofibers (NFs) in aligned arrays either neglect or assume a simple functional form for the curvature of the NFs, commonly known as the NF waviness. However, since such assumptions cannot adequately describe the waviness of real NFs, errors that can exceed 10% in the predicted inter-NF separation can result. Here we use a theoretical framework capable of simulating >10(5) NFs with stochastic three-dimensional morphologies to quantify NF waviness on an easily accessible measure of the morphology, the inter-NF spacing, for a range of NF volume fractions. The presented scaling of inter-NF spacing with waviness is then used to study the morphology evolution of aligned carbon nanotube (A-CNT) arrays during packing, showing that the effective two-dimensional coordination number of the A-CNTs increases much faster than previously reported during close packing, and that hexagonal close packing can successfully describe the packing morphology of the A-CNTs at volume fractions greater than 40 vol%. PMID:26658525

  11. 7 CFR 917.13 - Pack.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 8 2011-01-01 2011-01-01 false Pack. 917.13 Section 917.13 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE FRESH PEARS AND PEACHES GROWN IN...

  12. Monkey Baker in bio-pack

    NASA Technical Reports Server (NTRS)

    1959-01-01

    A squirrel monkey, Baker, in bio-pack couch being readied for Jupiter (AM-18 flight). Jupiter, AM-18 mission, also carried an American-born rhesus monkey, Able into suborbit. The flight was successful and both monkeys were recovered in good condition. AM-18 was launched on May 28, 1959.

  13. 7 CFR 917.13 - Pack.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 8 2013-01-01 2013-01-01 false Pack. 917.13 Section 917.13 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS AND ORDERS; FRUITS, VEGETABLES, NUTS), DEPARTMENT OF AGRICULTURE FRESH PEARS AND PEACHES GROWN IN...

  14. 7 CFR 917.13 - Pack.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 8 2012-01-01 2012-01-01 false Pack. 917.13 Section 917.13 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE FRESH PEARS AND PEACHES GROWN IN...

  15. 7 CFR 917.13 - Pack.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 8 2014-01-01 2014-01-01 false Pack. 917.13 Section 917.13 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS AND ORDERS; FRUITS, VEGETABLES, NUTS), DEPARTMENT OF AGRICULTURE FRESH PEARS AND PEACHES GROWN IN...

  16. Random close packing in protein cores

    NASA Astrophysics Data System (ADS)

    Ohern, Corey

    Shortly after the determination of the first protein x-ray crystal structures, researchers analyzed their cores and reported packing fractions ϕ ~ 0 . 75 , a value that is similar to close packing equal-sized spheres. A limitation of these analyses was the use of `extended atom' models, rather than the more physically accurate `explicit hydrogen' model. The validity of using the explicit hydrogen model is proved by its ability to predict the side chain dihedral angle distributions observed in proteins. We employ the explicit hydrogen model to calculate the packing fraction of the cores of over 200 high resolution protein structures. We find that these protein cores have ϕ ~ 0 . 55 , which is comparable to random close-packing of non-spherical particles. This result provides a deeper understanding of the physical basis of protein structure that will enable predictions of the effects of amino acid mutations and design of new functional proteins. We gratefully acknowledge the support of the Raymond and Beverly Sackler Institute for Biological, Physical, and Engineering Sciences, National Library of Medicine training grant T15LM00705628 (J.C.G.), and National Science Foundation DMR-1307712 (L.R.).

  17. Action Pack: Financial Resources for Training.

    ERIC Educational Resources Information Center

    Wheelock Coll., Boston, MA. Center for Career Development in Early Care and Education.

    In order to successfully implement an early childhood career development system, it is necessary to coordinate funds and training opportunities from many different sources. This action pack is designed to help individuals involved in such statewide efforts learn how to navigate the financing system that currently supports training for early care…

  18. Barrier properties of k-mer packings

    NASA Astrophysics Data System (ADS)

    Lebovka, N.; Khrapatiy, S.; Vygornitskyi; Pivovarova, N.

    2014-08-01

    This work discusses numerical studies of the barrier properties of k-mer packings by the Monte Carlo method. The studied variants of regular and non-regular arrangements on a square lattice included models of random sequential adsorption (RSA) and random deposition (RD). The discrete problem of diffusion through the bonds of a square lattice was considered. The k-mers were perfectly oriented perpendicular to the diffusion direction and blocked certain fraction of bonds fb against diffusion. The barrier efficiency was estimated by calculation of the ratio D/Do where D is diffusion coefficient in direction perpendicular to the orientation of k-mers and Do is the same value for diffusion on the square lattice without blocked bonds, i.e., at fb=0. The value of k varied from 1 to 512 and different lattice sizes up to L=8192 lattice units were used. For dense packings (p=1), the obtained D/Do versus fb dependences deviated from the theoretical prediction of effective medium (EM) theory and deviation was the most obvious for the regular non-staggered arrangement. For loose RSA and RD packings, the percolation like-behavior of D/Do with threshold at fb=p∞ was observed and the data evidenced that their barrier properties at large values of k may be more effective than those of some dense packings. Such anomalous behavior can reflect the details of k-mer spatial organization (aggregation) and structure of pores in RD and RSA packings. The contradictions between simulation data and predictions of EM theory were also discussed.

  19. Experimental demonstration of nonuniform frequency distributions of granular packings

    NASA Astrophysics Data System (ADS)

    Gao, Guo-Jie; Blawzdziewicz, Jerzy; O'Hern, Corey S.; Shattuck, Mark

    2009-12-01

    We developed an experimental method to generate mechanically stable (MS) packings of frictionless disks and performed coordinated experiments and simulations to characterize MS packings in small systems. For a given system geometry, MS packings occur as discrete, well-separated points in configuration space with probabilities that vary by many orders of magnitude and are robust with respect to the packing preparation. Over a continuous range of system geometries, MS packings occur as distinct geometrical families and only a small fraction of families are sampled via quasistatic dynamics. These results suggest that the most frequent MS packings may dominate the structural and mechanical properties of dense granular media.

  20. High-Entropy Alloys in Hexagonal Close-Packed Structure

    NASA Astrophysics Data System (ADS)

    Gao, M. C.; Zhang, B.; Guo, S. M.; Qiao, J. W.; Hawk, J. A.

    2016-07-01

    The microstructures and properties of high-entropy alloys (HEAs) based on the face-centered cubic and body-centered cubic structures have been studied extensively in the literature, but reports on HEAs in the hexagonal close-packed (HCP) structure are very limited. Using an efficient strategy in combining phase diagram inspection, CALPHAD modeling, and ab initio molecular dynamics simulations, a variety of new compositions are suggested that may hold great potentials in forming single-phase HCP HEAs that comprise rare earth elements and transition metals, respectively. Experimental verification was carried out on CoFeReRu and CoReRuV using X-ray diffraction, scanning electron microscopy, and energy dispersion spectroscopy.

  1. 21 CFR 133.124 - Cold-pack cheese food.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 2 2011-04-01 2011-04-01 false Cold-pack cheese food. 133.124 Section 133.124... Cheese and Related Products § 133.124 Cold-pack cheese food. (a)(1) Cold-pack cheese food is the food... specified in paragraph (e) of this section may be used. (2) All cheeses used in a cold-pack cheese food...

  2. Use of succinoglycan biopolymer for gravel packing

    SciTech Connect

    Sanz, G.P.; Gunningham, M.C.; Samuel, A.J. . E P Lab.); Lau, H.C.

    1994-06-01

    This paper presents the results of laboratory experiments and field trials on a polysaccharide biopolymer, succinoglycan, for use in gravel packing. This biopolymer causes minimal formation damage and has unique rheological properties that combine high shear-thinning behavior with temperature-induced viscosity breakback; thus, it can be used without breakers. A scouting study has been carried out at KSEPL to identify new viscosifiers with better rheological properties that cause minimal formation damage. Ideally, breakers should not be required and on-site polymer preparation procedures should be simple enough to give reliable, repeatable performances. For slurry-pack-type operations, the polysaccharide biopolymer succinoglycan was identified as the best candidate. The biopolymer was developed for EOR during 1980--83 at the Sittingbourne Research Centre, Shell Research Ltd., U.K., and is marketed by Shell Intl. Chemical Co. Ltd. as Shellflo-S.''

  3. USDC based rapid penetrator of packed soil

    NASA Technical Reports Server (NTRS)

    Bao, Xiaoqi; Bar-Cohen, Yoseph; Chang, Zensheu; Sherrit, Stewart; Badescu, Mircea

    2006-01-01

    Environment protection requires more testing and analysis tools. To detect buried chemical containers or other objects embedded in soil and avoid possible damages of them, a penetrator of packed soil operated using low pushing force was developed. The design was based on a novel driving mechanism of the ultrasonic/sonic driller/corer (USDC) device developed in the NDEAA lab at JPL [Bar-Cohen et al 2001, Bao et al 2003]. In the penetrator, a small free-flying mass is energized by a piezoelectric transducer and impacts a rod probe on its shoulder at frequencies of hundreds times per second. The impacts help the probe to penetrate the packed soil rapidly. A great reduction of the needed pushing force for penetration was achieved. The details of the design of the prototype penetrator and the results of performance tests are presented.

  4. Is incest common in gray wolf packs?

    USGS Publications Warehouse

    Smith, D.; Meier, T.; Geffen, E.; Mech, L.D.; Burch, J.W.; Adams, L.G.; Wayne, R.K.

    1997-01-01

    Wolf packs generally consist of a breeding pair and their maturing offspring that help provision and protect pack young. Because the reproductive tenure in wolves often is short, reproductively mature offspring might replace their parents, resulting in sibling or parent-offspring matings. To determine the extent of incestuous pairings, we measure relatedness based on variability in 20 microsatellite loci of mated pairs, parent-offspring pairs and siblings in two populations of gray wolves. Our 16 sampled mated pairs had values of relatedness not overlapping those of known parent-offspring or sibling dyads, which is consistent with their being unrelated or distantly related. These results suggest that full siblings or a parent and their offspring rarely mate and that incest avoidance is an important constraint on gray wolf behavioral ecology.

  5. Breakup of Pack Ice, Antarctic Ice Shelf

    NASA Technical Reports Server (NTRS)

    1991-01-01

    Breakup of Pack Ice along the periphery of the Antarctic Ice Shelf (53.5S, 3.0E) produced this mosaic of ice floes off the Antarctic Ice Shelf. Strong offshore winds, probably associated with strong katabatic downdrafts from the interior of the continent, are seen peeling off the edges of the ice shelf into long filamets of sea ice, icebergs, bergy bits and growlers to flow northward into the South Atlantic Ocean. 53.5S, 3.0E

  6. On the perfect hexagonal packing of rods

    NASA Astrophysics Data System (ADS)

    Starostin, E. L.

    2006-04-01

    In most cases the hexagonal packing of fibrous structures or rods extremizes the energy of interaction between strands. If the strands are not straight, then it is still possible to form a perfect hexatic bundle. Conditions under which the perfect hexagonal packing of curved tubular structures may exist are formulated. Particular attention is given to closed or cycled arrangements of the rods like in the DNA toroids and spools. The closure or return constraints of the bundle result in an allowable group of automorphisms of the cross-sectional hexagonal lattice. The structure of this group is explored. Examples of open helical-like and closed toroidal-like bundles are presented. An expression for the elastic energy of a perfectly packed bundle of thin elastic rods is derived. The energy accounts for both the bending and torsional stiffnesses of the rods. It is shown that equilibria of the bundle correspond to solutions of a variational problem formulated for the curve representing the axis of the bundle. The functional involves a function of the squared curvature under the constraints on the total torsion and the length. The Euler-Lagrange equations are obtained in terms of curvature and torsion and due to the existence of the first integrals the problem is reduced to the quadrature. The three-dimensional shape of the bundle may be readily reconstructed by integration of the Ilyukhin-type equations in special cylindrical coordinates. The results are of universal nature and are applicable to various fibrous structures, in particular, to intramolecular liquid crystals formed by DNA condensed in toroids or packed inside the viral capsids. International Workshop on Biopolymers: Thermodynamics, Kinetics and Mechanics of DNA, RNA and Proteins, 30.05.2005-3.06.2005, The Abdus Salam International Centre for Theoretical Physics (ICTP), Trieste, Italy.

  7. Partitioning And Packing Equations For Parallel Processing

    NASA Technical Reports Server (NTRS)

    Arpasi, Dale J.; Milner, Edward J.

    1989-01-01

    Algorithm developed to identify parallelism in set of coupled ordinary differential equations that describe physical system and to divide set into parallel computational paths, along with parts of solution proceeds independently of others during at least part of time. Path-identifying algorithm creates number of paths consisting of equations that must be computed serially and table that gives dependent and independent arguments and "can start," "can end," and "must end" times of each equation. "Must end" time used subsequently by packing algorithm.

  8. 7 CFR 51.2840 - Export packing requirements.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Export packing requirements. 51.2840 Section 51.2840 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards...) Export Packing Requirements § 51.2840 Export packing requirements. Onions specified as meeting...

  9. 1. Contextual view looking west, showing packing house and Union ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. Contextual view looking west, showing packing house and Union Ice building, which is located to the north of Packing House (right hand side in photo) - College Heights Lemon Packing House, 519-532 West First Street, Claremont, Los Angeles County, CA

  10. 48 CFR 211.272 - Alternate preservation, packaging, and packing.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ..., packaging, and packing. 211.272 Section 211.272 Federal Acquisition Regulations System DEFENSE ACQUISITION... Requirements Documents 211.272 Alternate preservation, packaging, and packing. Use the provision at 252.211-7004, Alternate Preservation, Packaging, and Packing, in solicitations which include...

  11. 48 CFR 211.272 - Alternate preservation, packaging, and packing.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ..., packaging, and packing. 211.272 Section 211.272 Federal Acquisition Regulations System DEFENSE ACQUISITION... Requirements Documents 211.272 Alternate preservation, packaging, and packing. Use the provision at 252.211-7004, Alternate Preservation, Packaging, and Packing, in solicitations which include...

  12. 48 CFR 211.272 - Alternate preservation, packaging, and packing.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ..., packaging, and packing. 211.272 Section 211.272 Federal Acquisition Regulations System DEFENSE ACQUISITION... Requirements Documents 211.272 Alternate preservation, packaging, and packing. Use the provision at 252.211-7004, Alternate Preservation, Packaging, and Packing, in solicitations which include...

  13. 48 CFR 211.272 - Alternate preservation, packaging, and packing.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ..., packaging, and packing. 211.272 Section 211.272 Federal Acquisition Regulations System DEFENSE ACQUISITION... Requirements Documents 211.272 Alternate preservation, packaging, and packing. Use the provision at 252.211-7004, Alternate Preservation, Packaging, and Packing, in solicitations which include...

  14. 48 CFR 211.272 - Alternate preservation, packaging, and packing.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ..., packaging, and packing. 211.272 Section 211.272 Federal Acquisition Regulations System DEFENSE ACQUISITION... Requirements Documents 211.272 Alternate preservation, packaging, and packing. Use the provision at 252.211-7004, Alternate Preservation, Packaging, and Packing, in solicitations which include...

  15. 36 CFR 34.10 - Saddle and pack animals.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 36 Parks, Forests, and Public Property 1 2014-07-01 2014-07-01 false Saddle and pack animals. 34... INTERIOR EL PORTAL ADMINISTRATIVE SITE REGULATIONS § 34.10 Saddle and pack animals. The use of saddle and pack animals is prohibited without a permit from the Superintendent....

  16. 36 CFR 34.10 - Saddle and pack animals.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 36 Parks, Forests, and Public Property 1 2013-07-01 2013-07-01 false Saddle and pack animals. 34... INTERIOR EL PORTAL ADMINISTRATIVE SITE REGULATIONS § 34.10 Saddle and pack animals. The use of saddle and pack animals is prohibited without a permit from the Superintendent....

  17. 36 CFR 34.10 - Saddle and pack animals.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 36 Parks, Forests, and Public Property 1 2010-07-01 2010-07-01 false Saddle and pack animals. 34... INTERIOR EL PORTAL ADMINISTRATIVE SITE REGULATIONS § 34.10 Saddle and pack animals. The use of saddle and pack animals is prohibited without a permit from the Superintendent....

  18. 36 CFR 34.10 - Saddle and pack animals.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 36 Parks, Forests, and Public Property 1 2012-07-01 2012-07-01 false Saddle and pack animals. 34... INTERIOR EL PORTAL ADMINISTRATIVE SITE REGULATIONS § 34.10 Saddle and pack animals. The use of saddle and pack animals is prohibited without a permit from the Superintendent....

  19. 36 CFR 34.10 - Saddle and pack animals.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 36 Parks, Forests, and Public Property 1 2011-07-01 2011-07-01 false Saddle and pack animals. 34... INTERIOR EL PORTAL ADMINISTRATIVE SITE REGULATIONS § 34.10 Saddle and pack animals. The use of saddle and pack animals is prohibited without a permit from the Superintendent....

  20. 36 CFR 1002.16 - Horses and pack animals.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 36 Parks, Forests, and Public Property 3 2014-07-01 2014-07-01 false Horses and pack animals. 1002... AND RECREATION § 1002.16 Horses and pack animals. The following are prohibited: (a) The use of animals... horses or pack animals outside of trails, routes or areas designated for their use. (c) The use of...

  1. 36 CFR 2.16 - Horses and pack animals.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 36 Parks, Forests, and Public Property 1 2014-07-01 2014-07-01 false Horses and pack animals. 2.16... RESOURCE PROTECTION, PUBLIC USE AND RECREATION § 2.16 Horses and pack animals. The following are prohibited... equipment. (b) The use of horses or pack animals outside of trails, routes or areas designated for their...

  2. 36 CFR 2.16 - Horses and pack animals.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 36 Parks, Forests, and Public Property 1 2010-07-01 2010-07-01 false Horses and pack animals. 2.16... RESOURCE PROTECTION, PUBLIC USE AND RECREATION § 2.16 Horses and pack animals. The following are prohibited... equipment. (b) The use of horses or pack animals outside of trails, routes or areas designated for their...

  3. 36 CFR 2.16 - Horses and pack animals.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 36 Parks, Forests, and Public Property 1 2013-07-01 2013-07-01 false Horses and pack animals. 2.16... RESOURCE PROTECTION, PUBLIC USE AND RECREATION § 2.16 Horses and pack animals. The following are prohibited... equipment. (b) The use of horses or pack animals outside of trails, routes or areas designated for their...

  4. 36 CFR 1002.16 - Horses and pack animals.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 36 Parks, Forests, and Public Property 3 2011-07-01 2011-07-01 false Horses and pack animals. 1002... AND RECREATION § 1002.16 Horses and pack animals. The following are prohibited: (a) The use of animals... horses or pack animals outside of trails, routes or areas designated for their use. (c) The use of...

  5. 36 CFR 2.16 - Horses and pack animals.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 36 Parks, Forests, and Public Property 1 2011-07-01 2011-07-01 false Horses and pack animals. 2.16... RESOURCE PROTECTION, PUBLIC USE AND RECREATION § 2.16 Horses and pack animals. The following are prohibited... equipment. (b) The use of horses or pack animals outside of trails, routes or areas designated for their...

  6. 36 CFR 1002.16 - Horses and pack animals.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 36 Parks, Forests, and Public Property 3 2010-07-01 2010-07-01 false Horses and pack animals. 1002... AND RECREATION § 1002.16 Horses and pack animals. The following are prohibited: (a) The use of animals... horses or pack animals outside of trails, routes or areas designated for their use. (c) The use of...

  7. 36 CFR 1002.16 - Horses and pack animals.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 36 Parks, Forests, and Public Property 3 2013-07-01 2012-07-01 true Horses and pack animals. 1002... AND RECREATION § 1002.16 Horses and pack animals. The following are prohibited: (a) The use of animals... horses or pack animals outside of trails, routes or areas designated for their use. (c) The use of...

  8. 36 CFR 1002.16 - Horses and pack animals.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 36 Parks, Forests, and Public Property 3 2012-07-01 2012-07-01 false Horses and pack animals. 1002... AND RECREATION § 1002.16 Horses and pack animals. The following are prohibited: (a) The use of animals... horses or pack animals outside of trails, routes or areas designated for their use. (c) The use of...

  9. 36 CFR 2.16 - Horses and pack animals.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 36 Parks, Forests, and Public Property 1 2012-07-01 2012-07-01 false Horses and pack animals. 2.16... RESOURCE PROTECTION, PUBLIC USE AND RECREATION § 2.16 Horses and pack animals. The following are prohibited... equipment. (b) The use of horses or pack animals outside of trails, routes or areas designated for their...

  10. Symmetric scrolled packings of multilayered carbon nanoribbons

    NASA Astrophysics Data System (ADS)

    Savin, A. V.; Korznikova, E. A.; Lobzenko, I. P.; Baimova, Yu. A.; Dmitriev, S. V.

    2016-06-01

    Scrolled packings of single-layer and multilayer graphene can be used for the creation of supercapacitors, nanopumps, nanofilters, and other nanodevices. The full atomistic simulation of graphene scrolls is restricted to consideration of relatively small systems in small time intervals. To overcome this difficulty, a two-dimensional chain model making possible an efficient calculation of static and dynamic characteristics of nanoribbon scrolls with allowance for the longitudinal and bending stiffness of nanoribbons is proposed. The model is extended to the case of scrolls of multilayer graphene. Possible equilibrium states of symmetric scrolls of multilayer carbon nanotribbons rolled up so that all nanoribbons in the scroll are equivalent are found. Dependences of the number of coils, the inner and outer radii, lowest vibrational eigenfrequencies of rolled packages on the length L of nanoribbons are obtained. It is shown that the lowest vibrational eigenfrequency of a symmetric scroll decreases with a nanoribbon length proportionally to L -1. It is energetically unfavorable for too short nanoribbons to roll up, and their ground state is a stack of plane nanoribbons. With an increasing number k of layers, the nanoribbon length L necessary for creation of symmetric scrolls increases. For a sufficiently small number of layers k and a sufficiently large nanoribbon length L, the scrolled packing has the lowest energy as compared to that of stack of plane nanoribbons and folded structures. The results can be used for development of nanomaterials and nanodevices on the basis of graphene scrolled packings.

  11. Probe with integrated heater and thermocouple pack

    SciTech Connect

    McCulloch, Reg W.; Dial, Ralph E.; Finnell, Wilber K. R.

    1990-01-01

    A probe for measuring heat includes an elongate rod fitted within a sheath, and a plurality of annular recesses are formed on the surface of the rod in a spaced-apart relationship to form annular chambers that are resistant to heat flow. A longitudinal bore extends axially into the rod and within the cylinders defined by the annular chambers, and an integrated heater and thermocouple pack is dimensioned to fit within the bore. In construction, the integrated pack includes a plurality of wires disposed in electrical insulation within a sheath and a heater cable. These wires include one common wire and a plurality of thermocuple wires. The common wire is constructed of one type of conductive material while the thermocouple wires are each constructed of two types of materials so that at least one thermocouple junction is formed therein. All of the wires extend the length of the integrated pack and are connected together at their ends. The thermocouple wires are constructed to form thermocouple junctions proximate to each annular chamber for producing electromotive forces corresponding to the temperature of the rod within the annular chambers relative to outside the chambers. In the preferred embodiment, each thermocouple wire forms two thermocouple junctions, one junction being disposed within an annular chamber and the second junction being disposed outside of, but proximate to, the same annular chamber. In one embodiment two thermocouple wires are configured to double the sensitivity of the probe in one region.

  12. Influence of fiber packing structure on permeability

    NASA Technical Reports Server (NTRS)

    Cai, Zhong; Berdichevsky, Alexander L.

    1993-01-01

    The study on the permeability of an aligned fiber bundle is the key building block in modeling the permeability of advanced woven and braided preforms. Available results on the permeability of fiber bundles in the literature show that a substantial difference exists between numerical and analytical calculations on idealized fiber packing structures, such as square and hexagonal packing, and experimental measurements on practical fiber bundles. The present study focuses on the variation of the permeability of a fiber bundle under practical process conditions. Fiber bundles are considered as containing openings and fiber clusters within the bundle. Numerical simulations on the influence of various openings on the permeability were conducted. Idealized packing structures are used, but with introduced openings distributed in different patterns. Both longitudinal and transverse flow are considered. The results show that openings within the fiber bundle have substantial effect on the permeability. In the longitudinal flow case, the openings become the dominant flow path. In the transverse flow case, the fiber clusters reduce the gap sizes among fibers. Therefore the permeability is greatly influenced by these openings and clusters, respectively. In addition to the porosity or fiber volume fraction, which is commonly used in the permeability expression, another fiber bundle status parameter, the ultimate fiber volume fraction, is introduced to capture the disturbance within a fiber bundle.

  13. Probe with integrated heater and thermocouple pack

    DOEpatents

    McCulloch, Reginald W.; Dial, Ralph E.; Finnell, Wilber K. R.

    1988-01-01

    A probe for measuring heat includes an elongate rod fitted within a sheath, and a plurality of annular recesses are formed on the surface of the rod in a spaced-apart relationship to form annular chambers that are resistant to heat flow. A longitudinal bore extends axially into the rod and within the cylinders defined by the annular chambers, and an integrated heater and thermocouple pack is dimensioned to fit within the bore. In construction, the integrated pack includes a plurality of wires disposed in electrical insulation within a sheath and a heater cable. These wires include one common wire and a plurality of thermocouple wires. The common wire is constructed of one type of conductive material while the thermocouple wires are each constructed of two types of materials so that at least one thermocouple junction is formed therein. All of the wires extend the length of the integrated pack and are connected together at their ends. The thermocouple wires are constructed to form thermocouple junctions proximate to each annular chamber for producing electromotive forces corresponding to the temperature of the rod within the annular chambers relative to outside the chambers. In the preferred embodiment, each thermocouple wire forms two thermocouple junctions, one junction being disposed within an annular chamber and the second junction being disposed outside of, but proximate to, the same annular chamber. In one embodiment two thermocouple wires are configured to double the sensitivity of the probe in one region.

  14. Eating less from bigger packs: Preventing the pack size effect with diet primes.

    PubMed

    Versluis, Iris; Papies, Esther K

    2016-05-01

    An increase in the package size of food has been shown to lead to an increase in energy intake from this food, the so-called pack size effect. Previous research has shown that providing diet-concerned individuals with a reminder, or prime, of their dieting goal can help them control their consumption. Here, we investigated if providing such a prime is also effective for reducing the magnitude of the pack size effect. We conducted two experiments in which the cover of a dieting magazine (Experiment 1) and diet-related commercials (Experiment 2) served as diet goal primes. Both experiments had a 2 (pack size: small vs. large) × 2 (prime: diet vs. control) × 2 (dietary restraint: high vs. low) between participants design. We measured expected consumption of four snack foods in Experiment 1 (N = 477), and actual consumption of M&M's in Experiment 2 (N = 224). Results showed that the diet prime reduced the pack size effect for both restrained and unrestrained eaters in Experiment 1 and for restrained eaters only in Experiment 2. Although effect sizes were small, these findings suggest that a diet prime motivates restrained eaters to limit their consumption, and as a result the pack size has less influence on the amount consumed. We discuss limitations of this research as well as potential avenues for further research and theoretical and practical implications. PMID:26876911

  15. Volatile species in halide-activated-diffusion coating packs

    NASA Technical Reports Server (NTRS)

    Bianco, Robert; Rapp, Robert A.; Jacobson, Nathan S.

    1992-01-01

    An atmospheric pressure sampling mass spectrometer was used to identify the vapor species generated in a halide-activated cementation pack. Pack powder mixtures containing a Cr-Al binary masteralloy powder, an NH4Cl activator salt, and either ZrO2 or Y2O3 (or neither) were analyzed at 1000 C. Both the equilibrium calculations for the pack and mass spectrometer results indicated that volatile AlCl(x) and CrCl(y) species were generated by the pack powder mixture; in packs containing the reactive element oxide, volatile ZrCl(z) and YCl(w) species were formed by the conversion of their oxide sources.

  16. Dense packings of polyhedra: Platonic and Archimedean solids

    NASA Astrophysics Data System (ADS)

    Torquato, S.; Jiao, Y.

    2009-10-01

    Understanding the nature of dense particle packings is a subject of intense research in the physical, mathematical, and biological sciences. The preponderance of previous work has focused on spherical particles and very little is known about dense polyhedral packings. We formulate the problem of generating dense packings of nonoverlapping, nontiling polyhedra within an adaptive fundamental cell subject to periodic boundary conditions as an optimization problem, which we call the adaptive shrinking cell (ASC) scheme. This optimization problem is solved here (using a variety of multiparticle initial configurations) to find the dense packings of each of the Platonic solids in three-dimensional Euclidean space R3 , except for the cube, which is the only Platonic solid that tiles space. We find the densest known packings of tetrahedra, icosahedra, dodecahedra, and octahedra with densities 0.823…, 0.836…, 0.904…, and 0.947…, respectively. It is noteworthy that the densest tetrahedral packing possesses no long-range order. Unlike the densest tetrahedral packing, which must not be a Bravais lattice packing, the densest packings of the other nontiling Platonic solids that we obtain are their previously known optimal (Bravais) lattice packings. We also derive a simple upper bound on the maximal density of packings of congruent nonspherical particles and apply it to Platonic solids, Archimedean solids, superballs, and ellipsoids. Provided that what we term the “asphericity” (ratio of the circumradius to inradius) is sufficiently small, the upper bounds are relatively tight and thus close to the corresponding densities of the optimal lattice packings of the centrally symmetric Platonic and Archimedean solids. Our simulation results, rigorous upper bounds, and other theoretical arguments lead us to the conjecture that the densest packings of Platonic and Archimedean solids with central symmetry are given by their corresponding densest lattice packings. This can be

  17. Non-Euclidean geometry of twisted filament bundle packing

    PubMed Central

    Bruss, Isaac R.; Grason, Gregory M.

    2012-01-01

    Densely packed and twisted assemblies of filaments are crucial structural motifs in macroscopic materials (cables, ropes, and textiles) as well as synthetic and biological nanomaterials (fibrous proteins). We study the unique and nontrivial packing geometry of this universal material design from two perspectives. First, we show that the problem of twisted bundle packing can be mapped exactly onto the problem of disc packing on a curved surface, the geometry of which has a positive, spherical curvature close to the center of rotation and approaches the intrinsically flat geometry of a cylinder far from the bundle center. From this mapping, we find the packing of any twisted bundle is geometrically frustrated, as it makes the sixfold geometry of filament close packing impossible at the core of the fiber. This geometrical equivalence leads to a spectrum of close-packed fiber geometries, whose low symmetry (five-, four-, three-, and twofold) reflect non-Euclidean packing constraints at the bundle core. Second, we explore the ground-state structure of twisted filament assemblies formed under the influence of adhesive interactions by a computational model. Here, we find that the underlying non-Euclidean geometry of twisted fiber packing disrupts the regular lattice packing of filaments above a critical radius, proportional to the helical pitch. Above this critical radius, the ground-state packing includes the presence of between one and six excess fivefold disclinations in the cross-sectional order. PMID:22711799

  18. Improved Absolute Approximation Ratios for Two-Dimensional Packing Problems

    NASA Astrophysics Data System (ADS)

    Harren, Rolf; van Stee, Rob

    We consider the two-dimensional bin packing and strip packing problem, where a list of rectangles has to be packed into a minimal number of rectangular bins or a strip of minimal height, respectively. All packings have to be non-overlapping and orthogonal, i.e., axis-parallel. Our algorithm for strip packing has an absolute approximation ratio of 1.9396 and is the first algorithm to break the approximation ratio of 2 which was established more than a decade ago. Moreover, we present a polynomial time approximation scheme (mathcal{PTAS}) for strip packing where rotations by 90 degrees are permitted and an algorithm for two-dimensional bin packing with an absolute worst-case ratio of 2, which is optimal provided mathcal{P} not= mathcal{NP}.

  19. Structural characterization of the packings of granular regular polygons.

    PubMed

    Wang, Chuncheng; Dong, Kejun; Yu, Aibing

    2015-12-01

    By using a recently developed method for discrete modeling of nonspherical particles, we simulate the random packings of granular regular polygons with three to 11 edges under gravity. The effects of shape and friction on the packing structures are investigated by various structural parameters, including packing fraction, the radial distribution function, coordination number, Voronoi tessellation, and bond-orientational order. We find that packing fraction is generally higher for geometrically nonfrustrated regular polygons, and can be increased by the increase of edge number and decrease of friction. The changes of packing fraction are linked with those of the microstructures, such as the variations of the translational and orientational orders and local configurations. In particular, the free areas of Voronoi tessellations (which are related to local packing fractions) can be described by log-normal distributions for all polygons. The quantitative analyses establish a clearer picture for the packings of regular polygons. PMID:26764678

  20. Body Hair

    MedlinePlus

    ... girlshealth.gov/ Home Body Puberty Body hair Body hair Even before you get your first period , you ... removing pubic hair Ways to get rid of hair top Removing body hair can cause skin irritation, ...

  1. Using Latex Balls and Acrylic Resin Plates to Investigate the Stacking Arrangement and Packing Efficiency of Metal Crystals

    ERIC Educational Resources Information Center

    Ohashi, Atsushi

    2015-01-01

    A high-school third-year or undergraduate first-semester general chemistry laboratory experiment introducing simple-cubic, face-centered cubic, body-centered cubic, and hexagonal closest packing unit cells is presented. Latex balls and acrylic resin plates are employed to make each atomic arrangement. The volume of the vacant space in each cell is…

  2. Packed fluidized bed blanket for fusion reactor

    DOEpatents

    Chi, John W. H.

    1984-01-01

    A packed fluidized bed blanket for a fusion reactor providing for efficient radiation absorption for energy recovery, efficient neutron absorption for nuclear transformations, ease of blanket removal, processing and replacement, and on-line fueling/refueling. The blanket of the reactor contains a bed of stationary particles during reactor operation, cooled by a radial flow of coolant. During fueling/refueling, an axial flow is introduced into the bed in stages at various axial locations to fluidize the bed. When desired, the fluidization flow can be used to remove particles from the blanket.

  3. Simple cloud chambers using gel ice packs

    NASA Astrophysics Data System (ADS)

    Kamata, Masahiro; Kubota, Miki

    2012-07-01

    Although cloud chambers are highly regarded as teaching aids for radiation education, school teachers have difficulty in using cloud chambers because they have to prepare dry ice or liquid nitrogen before the experiment. We developed a very simple and inexpensive cloud chamber that uses the contents of gel ice packs which can substitute for dry ice or liquid nitrogen. The gel can be frozen in normal domestic freezers, and can be used repeatedly by re-freezing. The tracks of alpha-ray particles can be observed continuously for about 20 min, and the operation is simple and easy.

  4. Techdrill`s Drill Soft Pack One

    SciTech Connect

    Prieur, J.M.

    1993-12-01

    This article presents the main features of Drill Soft Pack One (DSP-One) version 1.4 developed by Techdrill (Paris, France). DSP-One is an integrated drilling engineering package that covers most aspects of drilling engineering. The package has been used for 6 months to prepare drilling programs and monitor wells. DSP-One is a PC-based, fully menu-driven program that runs on any IBM PC compatible. The program requires 550 KB of memory and 6 MB of hard-disk space. The software manufacture recommends a math coprocessor for speed and a VGA color monitor to achieve full benefit from the color graphic displays.

  5. Pictorial cigarette pack warnings: a meta-analysis of experimental studies

    PubMed Central

    Noar, Seth M; Hall, Marissa G; Francis, Diane B; Ribisl, Kurt M; Pepper, Jessica K; Brewer, Noel T

    2016-01-01

    Objective To inform international research and policy, we conducted a meta-analysis of the experimental literature on pictorial cigarette pack warnings. Data sources We systematically searched 7 computerised databases in April 2013 using several search terms. We also searched reference lists of relevant articles. Study selection We included studies that used an experimental protocol to test cigarette pack warnings and reported data on both pictorial and text-only conditions. 37 studies with data on 48 independent samples (N=33 613) met criteria. Data extraction and synthesis Two independent coders coded all study characteristics. Effect sizes were computed from data extracted from study reports and were combined using random effects meta-analytic procedures. Results Pictorial warnings were more effective than text-only warnings for 12 of 17 effectiveness outcomes (all p<0.05). Relative to text-only warnings, pictorial warnings (1) attracted and held attention better; (2) garnered stronger cognitive and emotional reactions; (3) elicited more negative pack attitudes and negative smoking attitudes and (4) more effectively increased intentions to not start smoking and to quit smoking. Participants also perceived pictorial warnings as being more effective than text-only warnings across all 8 perceived effectiveness outcomes. Conclusions The evidence from this international body of literature supports pictorial cigarette pack warnings as more effective than text-only warnings. Gaps in the literature include a lack of assessment of smoking behaviour and a dearth of theory-based research on how warnings exert their effects. PMID:25948713

  6. Fatal canine distemper infection in a pack of African wild dogs in the Serengeti ecosystem, Tanzania.

    PubMed

    Goller, Katja V; Fyumagwa, Robert D; Nikolin, Veljko; East, Marion L; Kilewo, Morris; Speck, Stephanie; Müller, Thomas; Matzke, Martina; Wibbelt, Gudrun

    2010-12-15

    In 2007, disease related mortality occurred in one African wild dog (Lycaon pictus) pack close to the north-eastern boundary of the Serengeti National Park, Tanzania. Histopathological examination of tissues from six animals revealed that the main pathologic changes comprised interstitial pneumonia and suppurative to necrotizing bronchopneumonia. Respiratory epithelial cells contained numerous eosinophilic intracytoplasmic inclusion bodies and multiple syncytial cells were found throughout the parenchymal tissue, both reacting clearly positive with antibodies against canine distemper virus (CDV) antigen. Phylogenetic analysis based on a 388 nucleotide (nt) fragment of the CDV phosphoprotein (P) gene revealed that the pack was infected with a CDV variant most closely related to Tanzanian variants, including those obtained in 1994 during a CDV epidemic in the Serengeti National Park and from captive African wild dogs in the Mkomazi Game Reserve in 2000. Phylogenetic analysis of a 335-nt fragment of the fusion (F) gene confirmed that the pack in 2007 was infected with a variant most closely related to one variant from 1994 during the epidemic in the Serengeti National Park from which a comparable fragment is available. Screening of tissue samples for concurrent infections revealed evidence of canine parvovirus, Streptococcus equi subsp. ruminatorum and Hepatozoon sp. No evidence of infection with Babesia sp. or rabies virus was found. Possible implications of concurrent infections are discussed. This is the first molecular characterisation of CDV in free-ranging African wild dogs and only the third confirmed case of fatal CDV infection in a free-ranging pack. PMID:20684868

  7. The effect of nanoparticle packing on capacitive electrode performance.

    PubMed

    Lee, Younghee; Noh, Seonmyeong; Kim, Min-Sik; Kong, Hye Jeong; Im, Kyungun; Kwon, Oh Seok; Kim, Sungmin; Yoon, Hyeonseok

    2016-06-01

    Nanoparticles pack together to form macro-scale electrodes in various types of devices, and thus, optimization of the nanoparticle packing is a prerequisite for the realization of a desirable device performance. In this work, we provide in-depth insight into the effect of nanoparticle packing on the performance of nanoparticle-based electrodes by combining experimental and computational findings. As a model system, polypyrrole nanospheres of three different diameters were used to construct pseudocapacitive electrodes, and the performance of the electrodes was examined at various nanosphere diameter ratios and mixed weight fractions. Two numerical algorithms are proposed to simulate the random packing of the nanospheres on the electrode. The binary nanospheres exhibited diverse, complicated packing behaviors compared with the monophasic packing of each nanosphere species. The packing of the two nanosphere species with lower diameter ratios at an optimized composition could lead to more dense packing of the nanospheres, which in turn could contribute to better device performance. The dense packing of the nanospheres would provide more efficient transport pathways for ions because of the reduced inter-nanosphere pore size and enlarged surface area for charge storage. Ultimately, it is anticipated that our approach can be widely used to define the concept of "the best nanoparticle packing" for desirable device performance. PMID:27242155

  8. Understanding shape entropy through local dense packing

    PubMed Central

    van Anders, Greg; Klotsa, Daphne; Ahmed, N. Khalid; Engel, Michael; Glotzer, Sharon C.

    2014-01-01

    Entropy drives the phase behavior of colloids ranging from dense suspensions of hard spheres or rods to dilute suspensions of hard spheres and depletants. Entropic ordering of anisotropic shapes into complex crystals, liquid crystals, and even quasicrystals was demonstrated recently in computer simulations and experiments. The ordering of shapes appears to arise from the emergence of directional entropic forces (DEFs) that align neighboring particles, but these forces have been neither rigorously defined nor quantified in generic systems. Here, we show quantitatively that shape drives the phase behavior of systems of anisotropic particles upon crowding through DEFs. We define DEFs in generic systems and compute them for several hard particle systems. We show they are on the order of a few times the thermal energy (kBT) at the onset of ordering, placing DEFs on par with traditional depletion, van der Waals, and other intrinsic interactions. In experimental systems with these other interactions, we provide direct quantitative evidence that entropic effects of shape also contribute to self-assembly. We use DEFs to draw a distinction between self-assembly and packing behavior. We show that the mechanism that generates directional entropic forces is the maximization of entropy by optimizing local particle packing. We show that this mechanism occurs in a wide class of systems and we treat, in a unified way, the entropy-driven phase behavior of arbitrary shapes, incorporating the well-known works of Kirkwood, Onsager, and Asakura and Oosawa. PMID:25344532

  9. Maximizing Singlet Fission by Intermolecular Packing.

    PubMed

    Wang, Linjun; Olivier, Yoann; Prezhdo, Oleg V; Beljonne, David

    2014-10-01

    A novel nonadiabatic molecular dynamics scheme is applied to study the singlet fission (SF) process in pentacene dimers as a function of longitudinal and lateral displacements of the molecular backbones. Detailed two-dimensional mappings of both instantaneous and long-term triplet yields are obtained, characterizing the advantageous and unfavorable stacking arrangements, which can be achieved by chemical substitutions to the bare pentacene molecule. We show that the SF rate can be increased by more than an order of magnitude through tuning the intermolecular packing, most notably when going from cofacial to the slipped stacked arrangements encountered in some pentacene derivatives. The simulations indicate that the SF process is driven by thermal electron-phonon fluctuations at ambient and high temperatures, expected in solar cell applications. Although charge-transfer states are key to construct continuous channels for SF, a large charge-transfer character of the photoexcited state is found to be not essential for efficient SF. The reported time domain study mimics directly numerous laser experiments and provides novel guidelines for designing efficient photovoltaic systems exploiting the SF process with optimum intermolecular packing. PMID:26278443

  10. Understanding shape entropy through local dense packing.

    PubMed

    van Anders, Greg; Klotsa, Daphne; Ahmed, N Khalid; Engel, Michael; Glotzer, Sharon C

    2014-11-11

    Entropy drives the phase behavior of colloids ranging from dense suspensions of hard spheres or rods to dilute suspensions of hard spheres and depletants. Entropic ordering of anisotropic shapes into complex crystals, liquid crystals, and even quasicrystals was demonstrated recently in computer simulations and experiments. The ordering of shapes appears to arise from the emergence of directional entropic forces (DEFs) that align neighboring particles, but these forces have been neither rigorously defined nor quantified in generic systems. Here, we show quantitatively that shape drives the phase behavior of systems of anisotropic particles upon crowding through DEFs. We define DEFs in generic systems and compute them for several hard particle systems. We show they are on the order of a few times the thermal energy ([Formula: see text]) at the onset of ordering, placing DEFs on par with traditional depletion, van der Waals, and other intrinsic interactions. In experimental systems with these other interactions, we provide direct quantitative evidence that entropic effects of shape also contribute to self-assembly. We use DEFs to draw a distinction between self-assembly and packing behavior. We show that the mechanism that generates directional entropic forces is the maximization of entropy by optimizing local particle packing. We show that this mechanism occurs in a wide class of systems and we treat, in a unified way, the entropy-driven phase behavior of arbitrary shapes, incorporating the well-known works of Kirkwood, Onsager, and Asakura and Oosawa. PMID:25344532

  11. Drag coefficients for winter Antarctic pack ice

    NASA Technical Reports Server (NTRS)

    Wamser, Christian; Martinson, Douglas G.

    1993-01-01

    Air-ice and ice-water drag coefficients referenced to 10-m-height winds for winter Antarctic pack ice based on measurements made from R/V Polarstern during the Winter Weddell Sea Project, 1986 (WWSP-86), and from R/V Akademik Fedorov during the Winter Weddell Gyre Study, 1989 (WWGS-89), are presented. The optimal values of the air-ice drag coefficients, made from turbulent flux measurements, are (1.79 +/- 0.06) x 10 exp -3 for WWSP-86 and (1.45 +/- 0.09) x 10 exp -3 for WWGS-89. A single ice-water drag coefficient for both WWSP-86 and WWGS-89, estimated from periods of ice drift throught to represent free-drift conditions, is (1.13 +/- 0.26) x 10 exp -3, and the ice-water turning angle is 18 +/- 18 deg. It is suggested that for a typical Antarctic winter pack ice cover, the ice cover reduces the momentum flux from the atmosphere to the ocean by about 33 percent.

  12. Immersion Calorimetry: Molecular Packing Effects in Micropores.

    PubMed

    Madani, S Hadi; Silvestre-Albero, Ana; Biggs, Mark J; Rodríguez-Reinoso, Francisco; Pendleton, Phillip

    2015-12-21

    Repeated and controlled immersion calorimetry experiments were performed to determine the specific surface area and pore-size distribution (PSD) of a well-characterized, microporous poly(furfuryl alcohol)-based activated carbon. The PSD derived from nitrogen gas adsorption indicated a narrow distribution centered at 0.57±0.05 nm. Immersion into liquids of increasing molecular sizes ranging from 0.33 nm (dichloromethane) to 0.70 nm (α-pinene) showed a decreasing enthalpy of immersion at a critical probe size (0.43-0.48 nm), followed by an increase at 0.48-0.56 nm, and a second decrease at 0.56-0.60 nm. This maximum has not been reported previously. After consideration of possible reasons for this new observation, it is concluded that the effect arises from molecular packing inside the micropores, interpreted in terms of 2D packing. The immersion enthalpy PSD was consistent with that from quenched solid density functional theory (QSDFT) analysis of the nitrogen adsorption isotherm. PMID:26394883

  13. Optimal packing of a rotating packed bed for H(2)S removal.

    PubMed

    Guo, Kai; Wen, Jiawu; Zhao, Ying; Wang, Yu; Zhang, Zhenzhen; Li, Zongxiang; Qian, Zhi

    2014-06-17

    The existence of H2S in a system could lead to catalyst deactivation, pipeline corrosion, and environmental pollution. A rotating packed bed (RPB), a novel reactor with high mass transfer efficiency and small dimension, is employed in this study to remove H2S. For RPB, the most significant section for mass transfer is the end-effect zone of packing. A mathematical model for liquid flow in the packing is established to quantify the length of the end-effect zone. A simple and effective visual experimental method is then proposed to investigate the end-effect zone in the RPB. A gas-liquid mass transfer experiment is finally employed to confirm the validity of the proposed mathematical model. With the aid of this model, the length of packing of a RPB used for pilot-scale H2S removal is optimized. The optimized RPB removes 99.8% of H2S (15 vol % to 0.03 vol %) from the system. The proposed model can help optimize the design of a RPB reactor. PMID:24798198

  14. Howling at two Minnesota wolf pack summer homesites

    USGS Publications Warehouse

    Harrington, F.H.; Mech, L.D.

    1978-01-01

    Howling sessions were monitored at two Minnesota wolf pack homesites for 2255 h between 29 April and 3 August 1973. All sessions recorded occurred from dusk through early morning, with an evening peak for one pack. Within a night, multiple sessions were grouped temporally, most occurring within an hour of one another. Howling rates for both packs increased throughout the homesite season, with the larger pack howling twice as frequently. The role of howling in both intrapack and interpack contexts was considered. Much of the howling seemed to be involved in the coordination of pack activities. Further, the low frequency and clumped temporal distribution of sessions suggest that howling plays a secondary role in interpack contexts to other modes such as scent marking during the homesite season, but may increase in relative importance once homesites are abandoned and pack travel becomes nomadic.

  15. Simulation of abuse tolerance of lithium-ion battery packs

    NASA Astrophysics Data System (ADS)

    Spotnitz, Robert M.; Weaver, James; Yeduvaka, Gowri; Doughty, D. H.; Roth, E. P.

    A simple approach for using accelerating rate calorimetry data to simulate the thermal abuse resistance of battery packs is described. The thermal abuse tolerance of battery packs is estimated based on the exothermic behavior of a single cell and an energy balance than accounts for radiative, conductive, and convective heat transfer modes of the pack. For the specific example of a notebook computer pack containing eight 18650-size cells, the effects of cell position, heat of reaction, and heat-transfer coefficient are explored. Thermal runaway of the pack is more likely to be induced by thermal runaway of a single cell when that cell is in good contact with other cells and is close to the pack wall.

  16. LC packing materials for pharmaceutical and biomedical analysis.

    PubMed

    Haginaka, Jun

    2002-11-01

    The author has prepared novel liquid chromatography (LC) packing materials for pharmaceutical and biomedical analysis. Those include LC packing materials for direct serum injection assays of drugs and their metabolites, LC packing materials for resolution of enantiomeric drugs, and uniformly sized molecularly imprinted polymers for drugs and their metabolites. This review article deals with the preparation of these materials and the pharmaceutical and biomedical applications of them in recognition of The Society of Chromatographic Sciences Award. PMID:12682997

  17. Fixed Packed Bed Reactors in Reduced Gravity

    NASA Technical Reports Server (NTRS)

    Motil, Brian J.; Balakotaiah, Vemuri; Kamotani, Yasuhiro; McCready, Mark J.

    2004-01-01

    We present experimental data on flow pattern transitions, pressure drop and flow characteristics for cocurrent gas-liquid flow through packed columns in microgravity. The flow pattern transition data indicates that the pulse flow regime exists over a wider range of gas and liquid flow rates under microgravity conditions compared to 1-g and the widely used Talmor map in 1-g is not applicable for predicting the transition boundaries. A new transition criterion between bubble and pulse flow in microgravity is proposed and tested using the data. Since there is no static head in microgravity, the pressure drop measured is the true frictional pressure drop. The pressure drop data, which has much smaller scatter than most reported 1-g data clearly shows that capillary effects can enhance the pressure drop (especially in the bubble flow regime) as much as 200% compared to that predicted by the single phase Ergun equation. The pressure drop data are correlated in terms of a two-phase friction factor and its dependence on the gas and liquid Reynolds numbers and the Suratman number. The influence of gravity on the pulse amplitude and frequency is also discussed and compared to that under normal gravity conditions. Experimental work is planned to determine the gas-liquid mass transfer coefficients. Because of enhanced interfacial effects, we expect the gas-liquid transfer coefficients k(L)a and k(G)a (where a is the gas-liquid interfacial area) to be higher in microgravity than in normal gravity at the same flow conditions. This will be verified by gas absorption experiments, with and without reaction in the liquid phase, using oxygen, carbon dioxide, water and dilute aqueous amine solutions. The liquid-solid mass transfer coefficient will also be determined in the bubble as well as the pulse flow regimes using solid benzoic acid particles in the packing and measuring their rate of dissolution. The mass transfer coefficients in microgravity will be compared to those in normal

  18. Fixed Packed Bed Reactors in Reduced Gravity

    NASA Technical Reports Server (NTRS)

    Motil, Brian J.; Balakotaiah, Vemuri; Kamotani, Yasuhiro; McCready, Mark J.

    2004-01-01

    We present experimental data on flow pattern transitions, pressure drop and flow characteristics for cocurrent gas-liquid flow through packed columns in microgravity. The flow pattern transition data indicates that the pulse flow regime exists over a wider range of gas and liquid flow rates under microgravity conditions compared to 1-g and the widely used Talmor map in 1-g is not applicable for predicting the transition boundaries. A new transition criterion between bubble and pulse flow in microgravity is proposed and tested using the data. Since there is no static head in microgravity, the pressure drop measured is the true frictional pressure drop. The pressure drop data, which has much smaller scatter than most reported 1-g data clearly shows that capillary effects can enhance the pressure drop (especially in the bubble flow regime) as much as 200% compared to that predicted by the single phase Ergun equation. The pressure drop data are correlated in terms of a two-phase friction factor and its dependence on the gas and liquid Reynolds numbers and the Suratman number. The influence of gravity on the pulse amplitude and frequency is also discussed and compared to that under normal gravity conditions. Experimental work is planned to determine the gas-liquid and liquid-solid mass transfer coefficients. Because of enhanced interfacial effects, we expect the gas-liquid transfer coefficients kLa and kGa (where a is the gas-liquid interfacial area) to be higher in microgravity than in normal gravity at the same flow conditions. This will be verified by gas absorption experiments, with and without reaction in the liquid phase, using oxygen, carbon dioxide, water and dilute aqueous amine solutions. The liquid-solid mass transfer coefficient will also be determined in the bubble as well as the pulse flow regimes using solid benzoic acid particles in the packing and measuring their rate of dissolution. The mass transfer coefficients in microgravity will be compared to

  19. Packed bed carburization of tantalum and tantalum alloy

    DOEpatents

    Lopez, P.C.; Rodriguez, P.J.; Pereyra, R.A.

    1999-06-29

    Packed bed carburization of a tantalum or tantalum alloy object is disclosed. A method for producing corrosion-resistant tantalum or tantalum alloy objects is described. The method includes the steps of placing the object in contact with a carburizing pack, heating the packed object in vacuum furnace to a temperature whereby carbon from the pack diffuses into the object forming grains with tantalum carbide along the grain boundaries, and etching the surface of the carburized object. This latter step removes tantalum carbides from the surface of the carburized tantalum object while leaving the tantalum carbide along the grain boundaries. 4 figs.

  20. Packed bed carburization of tantalum and tantalum alloy

    DOEpatents

    Lopez, Peter C.; Rodriguez, Patrick J.; Pereyra, Ramiro A.

    1999-01-01

    Packed bed carburization of a tantalum or tantalum alloy object. A method for producing corrosion-resistant tantalum or tantalum alloy objects is described. The method includes the steps of placing the object in contact with a carburizing pack, heating the packed object in vacuum furnace to a temperature whereby carbon from the pack diffuses into the object forming grains with tantalum carbide along the grain boundaries, and etching the surface of the carburized object. This latter step removes tantalum carbides from the surface of the carburized tantalum object while leaving the tantalum carbide along the grain boundaries.

  1. Human Error in Throat Pack Management: Report of Two Cases.

    PubMed

    Baranger, Violaine; Bon Mardion, Nicolas; Dureuil, Bertrand; Compère, Vincent

    2016-06-15

    Throat packs are frequently used after tracheal intubation during ear, nose, and throat surgery. We report 2 cases of complications related to throat packs retained at the end of surgery. Miscommunication between anesthesiology and surgery teams on throat pack management led to an upper gastrointestinal endoscopy examination under general anesthesia in the first case and to severe respiratory distress requiring tracheal reintubation in the second case. Our 2 case reports highlight the importance of good communication between anesthesiology and surgery teams and of standardized procedures and checklists for the management of throat packs to ensure patient safety. PMID:27301056

  2. Voronoi tessellation of the packing of fine uniform spheres

    NASA Astrophysics Data System (ADS)

    Yang, R. Y.; Zou, R. P.; Yu, A. B.

    2002-04-01

    The packing of uniform fine spherical particles ranging from 1 to 1000 μm has been simulated by means of discrete particle simulation. The packing structure is analyzed, facilitated by the well established Voronoi tessellation. The topological and metric properties of Voronoi polyhedra are quantified as a function of particle size and packing density. The results show that as particle size or packing density decreases, (i) the average face number of Voronoi polyhedra decreases, and the distributions of face number and edge number become broader and more asymmetric; (ii) the average perimeter and area of polyhedra increase, and the distributions of polyhedron surface area and volume become more flat and can be described by the log-normal distribution. The topological and metric properties depicted for the packing of fine particles differ either quantitatively or qualitatively from those reported in the literature although they all can be related to packing density. In particular, our results show that the average sphericity coefficient of Voronoi polyhedra varies with packing density, and although Aboav-Weaire's law is generally applicable, Lewis's law is not valid when packing density is low, which are contrary to the previous findings for other packing systems.

  3. Voronoi tessellation of the packing of fine uniform spheres.

    PubMed

    Yang, R Y; Zou, R P; Yu, A B

    2002-04-01

    The packing of uniform fine spherical particles ranging from 1 to 1000 microm has been simulated by means of discrete particle simulation. The packing structure is analyzed, facilitated by the well established Voronoi tessellation. The topological and metric properties of Voronoi polyhedra are quantified as a function of particle size and packing density. The results show that as particle size or packing density decreases, (i) the average face number of Voronoi polyhedra decreases, and the distributions of face number and edge number become broader and more asymmetric; (ii) the average perimeter and area of polyhedra increase, and the distributions of polyhedron surface area and volume become more flat and can be described by the log-normal distribution. The topological and metric properties depicted for the packing of fine particles differ either quantitatively or qualitatively from those reported in the literature although they all can be related to packing density. In particular, our results show that the average sphericity coefficient of Voronoi polyhedra varies with packing density, and although Aboav-Weaire's law is generally applicable, Lewis's law is not valid when packing density is low, which are contrary to the previous findings for other packing systems. PMID:12005816

  4. Understanding aging mechanisms in lithium-ion battery packs: From cell capacity loss to pack capacity evolution

    NASA Astrophysics Data System (ADS)

    Zheng, Yuejiu; Ouyang, Minggao; Lu, Languang; Li, Jianqiu

    2015-03-01

    Battery cell capacity loss is extensively studied so as to extend battery life in varied applications from portable consumer electronics to energy storage devices. Battery packs are constructed especially in energy storage devices to provide sufficient voltage and capacity. However, engineering practice indicates that battery packs always fade more critically than cells. We investigate the evolution of battery pack capacity loss by analyzing cell aging mechanisms using the "Electric quantity - Capacity Scatter Diagram (ECSD)" from a system point of view. The results show that cell capacity loss is not the sole contributor to pack capacity loss. The loss of lithium inventory variation at anodes between cells plays a significant role in pack capacity evolution. Therefore, we suggest more attention could be paid to the loss of lithium inventory at anodes in order to mitigate pack capacity degradation.

  5. Volatile Components from Packing Matrials, Rev. 2

    SciTech Connect

    Smith, R. A.

    2006-03-01

    An outgassing study was conducted on five packing materials, comprising two experiments. These materials comprised 277-4 borated concrete, Borobond4 concrete, polyethylene bags, silica-filled silicone rubber seals, and silicone foam padding. The purpose was measure the volume of gases which diffuse from packaging materials when sealed in containers. Two heating profiles were used to study the offgassing quantities in a set of accelerated aging tests. It was determined that the concretes contain a large quantity of water. The plastic materials hold much less moisture, with the silicone materials even consuming water, possibly due to the presence of silica filler. Polyethylene tends to degrade as the temperature is elevated and the foam stiffens.

  6. Hyperstaticity and loops in frictional granular packings

    NASA Astrophysics Data System (ADS)

    Tordesillas, Antoinette; Lam, Edward; Metzger, Philip T.

    2009-06-01

    The hyperstatic nature of granular packings of perfectly rigid disks is analyzed algebraically and through numerical simulation. The elementary loops of grains emerge as a fundamental element in addressing hyperstaticity. Loops consisting of an odd number of grains behave differently than those with an even number. For odd loops, the latent stresses are exterior and are characterized by the sum of frictional forces around each loop. For even loops, the latent stresses are interior and are characterized by the alternating sum of frictional forces around each loop. The statistics of these two types of loop sums are found to be Gibbsian with a "temperature" that is linear with the friction coefficient μ when μ<1.

  7. COLLOIDS. Colloidal matter: Packing, geometry, and entropy.

    PubMed

    Manoharan, Vinothan N

    2015-08-28

    Colloidal particles with well-controlled shapes and interactions are an ideal experimental system for exploring how matter organizes itself. Like atoms and molecules, these particles form bulk phases such as liquids and crystals. But they are more than just crude analogs of atoms; they are a form of matter in their own right, with complex and interesting collective behavior not seen at the atomic scale. Their behavior is affected by geometrical or topological constraints, such as curved surfaces or the shapes of the particles. Because the interactions between the particles are often short-ranged, we can understand the effects of these constraints using geometrical concepts such as packing. The geometrical viewpoint gives us a window into how entropy affects not only the structure of matter, but also the dynamics of how it forms. PMID:26315444

  8. New Packing Structure of Concentration Solar Receiver

    SciTech Connect

    Tsai, Shang-Yu; Lee, Yueh-Mu; Shih, Zun-Hao; Hong, Hwen-Fen; Shin, Hwa-Yuh; Kuo, Cherng-Tsong

    2010-10-14

    This paper presents a solution to the temperature issue in High Concentration Photovoltaic (HCPV) module device by using different thermal conductive material and packing structure. In general, the open-circuited voltage of a device reduces with the increase of temperature and therefore degrades its efficiency. The thermal conductive material we use in this paper, silicon, has a high thermal conductive coefficient (149 W/m{center_dot}K) and steady semiconductor properties which are suitable for the application of solar receiver in HCPV module. Solar cell was soldered on a metal-plated Si substrate with a thicker SiO{sub 2} film which acts as an insulating layer. Then it was mounted on an Al-based plate to obtain a better heat dissipating result.

  9. Probe with integrated heater and thermocouple pack

    SciTech Connect

    McCulloch, R.W.; Dial, R.E.; Finnell, W.R.

    1988-02-16

    A gamma thermometer probe for detecting heat produced within the thermometer probe is described comprising: an outer elongate thermometer sheath having a cylindrical cross-section, a length, an outer end and an inner end; an elongate rod having a cylindrical cross-section fitted within the elongate thermometer sheath, the rod being constructed of material that absorbs radiation and produces heat; annular recesses formed between the rod, and sheath and being spaced apart along the length of the rod, the recesses forming annular chambers that are resistive to heat flow; a longitudinal bore extending axially into the rod and being positioned to extend through the cylinders defined by the annular chambers; and an integrated thermocouple pack dimensioned to fit within the longitudinal bore and extending through the cylinders defined by the annular chambers.

  10. GlobiPack v. 1.0

    Energy Science and Technology Software Center (ESTSC)

    2010-03-31

    GlobiPack contains a small collection of optimization globalization algorithms. These algorithms are used by optimization and various nonlinear equation solver algorithms.Used as the line-search procedure with Newton and Quasi-Newton optimization and nonlinear equation solver methods. These are standard published 1-D line search algorithms such as are described in the book Nocedal and Wright Numerical Optimization: 2nd edition, 2006. One set of algorithms were copied and refactored from the existing open-source Trilinos package MOOCHO where themore » linear search code is used to globalize SQP methods. This software is generic to any mathematical optimization problem where smooth derivatives exist. There is no specific connection or mention whatsoever to any specific application, period. You cannot find more general mathematical software.« less

  11. Generation of Homogeneous Granular Packings:. Contact Dynamics Simulations at Constant Pressure Using Fully Periodic Boundaries

    NASA Astrophysics Data System (ADS)

    Shaebani, M. Reza; Unger, Tamás; Kertész, János

    The contact dynamics (CD) method is an efficient simulation technique of dense granular media where unilateral and frictional contact problems for a large number of rigid bodies have to be solved. In this paper, we present a modified version of the CD to generate homogeneous random packings of rigid grains. CD simulations are performed at constant external pressure, which allows the variation of the size of a periodically repeated cell. We follow the concept of the Andersen dynamics and show how it can be applied within the framework of the CD method. The main challenge here is to handle the interparticle interactions properly, which are based on constraint forces in CD. We implement the proposed algorithm, perform test simulations, and investigate the properties of the final packings.

  12. Theoretical elastic moduli for disordered packings of interconnected spheres

    NASA Astrophysics Data System (ADS)

    Zaccone, Alessio; Lattuada, Marco; Wu, Hua; Morbidelli, Massimo

    2007-11-01

    A theoretical model has been developed which provides analytical expressions for the elastic moduli of disordered isotropic ensembles of spheres interconnected by physical bonds. Young's and shear moduli have been derived assuming an ideal random isotropic network and the radial distribution function for disordered packings of spheres. The interparticle interactions are accounted for in terms of surface forces for the two distinct cases of perfectly rigid spheres and spheres deformable at contact. A theoretical expression is also derived in a similar way for the bulk or compressibility modulus. In this case, an atomistic approach has been followed based on the analogy with noble gas solids and colloidal crystals. Also in this case, disordered spatial distribution of the spheres is described statistically. For the case of colloidal aggregates, a total two-body mean-field interaction potential is used which includes the Born repulsion energy. This latter contribution plays an essential role in determining the compression behavior of systems of particles aggregated in the primary minimum of the potential well and, therefore, must not be neglected. Both the expression of the Young's modulus and that of the compressibility modulus derived in this work are found to be consistent with two distinct sets of experimental data which recently appeared in the literature.

  13. SAR imagery of the Grand Banks (Newfoundland) pack ice pack and its relationship to surface features

    NASA Technical Reports Server (NTRS)

    Argus, S. D.; Carsey, F. D.

    1988-01-01

    Synthetic Aperture Radar (SAR) data and aerial photographs were obtained over pack ice off the East Coast of Canada in March 1987 as part of the Labrador Ice Margin Experiment (LIMEX) pilot project. Examination of this data shows that although the pack ice off the Canadian East Coast appears essentially homogeneous to visible light imagery, two clearly defined zones of ice are apparent on C-band SAR imagery. To identify factors that create the zones seen on the radar image, aerial photographs were compared to the SAR imagery. Floe size data from the aerial photographs was compared to digital number values taken from SAR imagery of the same ice. The SAR data of the inner zone acquired three days apart over the melt period was also examined. The studies indicate that the radar response is governed by floe size and meltwater distribution.

  14. Sound Packing DNA: packing open circular DNA with low-intensity ultrasound

    NASA Astrophysics Data System (ADS)

    Park, Donghee; Jung, Bong-Kwang; Park, Hyunjin; Lee, Hyungbeen; Lee, Gyudo; Park, Jingam; Shin, Unchul; Won, Jong Ho; Jo, Yong Jun; Chang, Jin Woo; Lee, Sangwoo; Yoon, Daesung; Seo, Jongbum; Kim, Chul-Woo

    2015-04-01

    Supercoiling DNA (folding DNA into a more compact molecule) from open circular forms requires significant bending energy. The double helix is coiled into a higher order helix form; thus it occupies a smaller footprint. Compact packing of DNA is essential to improve the efficiency of gene delivery, which has broad implications in biology and pharmaceutical research. Here we show that low-intensity pulsed ultrasound can pack open circular DNA into supercoil form. Plasmid DNA subjected to 5.4 mW/cm2 intensity ultrasound showed significant (p-values <0.001) supercoiling compared to DNA without exposure to ultrasound. Radiation force induced from ultrasound and dragging force from the fluid are believed to be the main factors that cause supercoiling. This study provides the first evidence to show that low-intensity ultrasound can directly alter DNA topology. We anticipate our results to be a starting point for improved non-viral gene delivery.

  15. Sound Packing DNA: packing open circular DNA with low-intensity ultrasound

    PubMed Central

    Park, DongHee; Jung, Bong-Kwang; Park, Hyunjin; Lee, Hyungbeen; Lee, Gyudo; Park, Jingam; Shin, Unchul; Won, Jong Ho; Jo, Yong Jun; Chang, Jin Woo; Lee, Sangwoo; Yoon, Daesung; Seo, Jongbum; Kim, Chul-Woo

    2015-01-01

    Supercoiling DNA (folding DNA into a more compact molecule) from open circular forms requires significant bending energy. The double helix is coiled into a higher order helix form; thus it occupies a smaller footprint. Compact packing of DNA is essential to improve the efficiency of gene delivery, which has broad implications in biology and pharmaceutical research. Here we show that low-intensity pulsed ultrasound can pack open circular DNA into supercoil form. Plasmid DNA subjected to 5.4 mW/cm2 intensity ultrasound showed significant (p-values <0.001) supercoiling compared to DNA without exposure to ultrasound. Radiation force induced from ultrasound and dragging force from the fluid are believed to be the main factors that cause supercoiling. This study provides the first evidence to show that low-intensity ultrasound can directly alter DNA topology. We anticipate our results to be a starting point for improved non-viral gene delivery. PMID:25892035

  16. Measured Black Carbon Deposition on the Sierra Nevada Snow Pack and Implication for Snow Pack Retreat

    SciTech Connect

    Hadley, O.L.; Corrigan, C.E.; Kirchstetter, T.W.; Cliff, S.S.; Ramanathan, V.

    2010-01-12

    Modeling studies show that the darkening of snow and ice by black carbon deposition is a major factor for the rapid disappearance of arctic sea ice, mountain glaciers and snow packs. This study provides one of the first direct measurements for the efficient removal of black carbon from the atmosphere by snow and its subsequent deposition to the snow packs of California. The early melting of the snow packs in the Sierras is one of the contributing factors to the severe water problems in California. BC concentrations in falling snow were measured at two mountain locations and in rain at a coastal site. All three stations reveal large BC concentrations in precipitation, ranging from 1.7 ng/g to 12.9 ng/g. The BC concentrations in the air after the snow fall were negligible suggesting an extremely efficient removal of BC by snow. The data suggest that below cloud scavenging, rather than ice nuclei, was the dominant source of BC in the snow. A five-year comparison of BC, dust, and total fine aerosol mass concentrations at multiple sites reveals that the measurements made at the sampling sites were representative of large scale deposition in the Sierra Nevada. The relative concentration of iron and calcium in the mountain aerosol indicates that one-quarter to one-third of the BC may have been transported from Asia.

  17. CT -- Body

    MedlinePlus

    ... News Physician Resources Professions Site Index A-Z Computed Tomography (CT) - Body Computed tomography (CT) of the body uses special x-ray ... Body? What is CT Scanning of the Body? Computed tomography, more commonly known as a CT or CAT ...

  18. Rotating bearings in regular and irregular granular shear packings

    NASA Astrophysics Data System (ADS)

    Ström, J. A. Ã.

    2008-01-01

    For 2D regular dense packings of solid mono-size non-sliding disks there is a mechanism for bearing formation under shear that can be explained theoretically. There is, however, no easy way to extend this model to include random dense packings which would better describe natural packings. A numerical model that simulates shear deformation for both near-regular and irregular packings is used to demonstrate that rotating bearings appear roughly with the same density in random and regular packings. The main difference appears in the size distribution of the rotating clusters near the jamming threshold. The size distribution is well described by a scaling form with a large-size cut-off that seems to grow without bounds for regular packings at the jamming threshold, while it remains finite for irregular packings. At packing densities above the jamming transition there can be no shear, unless the disks are allowed to break. Breaking of disks induces a large number of small local bearings. Clusters of rotating particles may contribute to e.g. pre-rupture yielding in landslides, snow avalanches and to the formation of aseismic gaps in tectonic fault zones.

  19. 21 CFR 890.5730 - Moist heat pack.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Moist heat pack. 890.5730 Section 890.5730 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Therapeutic Devices § 890.5730 Moist heat pack....

  20. 21 CFR 890.5730 - Moist heat pack.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Moist heat pack. 890.5730 Section 890.5730 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Therapeutic Devices § 890.5730 Moist heat pack....

  1. 21 CFR 890.5730 - Moist heat pack.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Moist heat pack. 890.5730 Section 890.5730 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Therapeutic Devices § 890.5730 Moist heat pack....

  2. 21 CFR 890.5730 - Moist heat pack.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Moist heat pack. 890.5730 Section 890.5730 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Therapeutic Devices § 890.5730 Moist heat pack....

  3. GENERAL VIEW OF SOUTH AND WEST FACADES OF PACKING AND ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    GENERAL VIEW OF SOUTH AND WEST FACADES OF PACKING AND JOB SHOP; BUILDING TO LEFT IS PRODUCTION FACILITY FOR ALCOA, SMALL BRICK BUILDING AT FAR RIGHT ON HIGHER GROUND IS THE FORMER ELECTRIC LIGHT PLANT FOR ALLEGHENY VALLEY LIGHT COMPANY - Alcoa-New Kensington Works, Packing & Job Shop, New Kensington, Westmoreland County, PA

  4. Softening of stressed granular packings with resonant sound waves.

    PubMed

    Reichhardt, C J Olson; Lopatina, L M; Jia, X; Johnson, P A

    2015-08-01

    We perform numerical simulations of a two-dimensional bidisperse granular packing subjected to both a static confining pressure and a sinusoidal dynamic forcing applied by a wall on one edge of the packing. We measure the response experienced by a wall on the opposite edge of the packing and obtain the resonant frequency of the packing as the static or dynamic pressures are varied. Under increasing static pressure, the resonant frequency increases, indicating a velocity increase of elastic waves propagating through the packing. In contrast, when the dynamic amplitude is increased for fixed static pressure, the resonant frequency decreases, indicating a decrease in the wave velocity. This occurs both for compressional and for shear dynamic forcing and is in agreement with experimental results. We find that the average contact number Zc at the resonant frequency decreases with increasing dynamic amplitude, indicating that the elastic softening of the packing is associated with a reduced number of grain-grain contacts through which the elastic waves can travel. We image the excitations created in the packing and show that there are localized disturbances or soft spots that become more prevalent with increasing dynamic amplitude. Our results are in agreement with experiments on glass bead packings and earth materials such as sandstone and granite and may be relevant to the decrease in elastic wave velocities that has been observed to occur near fault zones after strong earthquakes, in surficial sediments during strong ground motion, and in structures during earthquake excitation. PMID:26382390

  5. 27 CFR 24.308 - Bottled or packed wine record.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... record. A proprietor who bottles, packs, or receives bottled or packed beverage wine in bond shall maintain a record, by tax class, as follows: (a) The date, kind of wine, the number and size of bottle or... or destroyed, breakage, used for tasting. The volume recorded as bottled for bottle...

  6. 27 CFR 24.308 - Bottled or packed wine record.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... record. A proprietor who bottles, packs, or receives bottled or packed beverage wine in bond shall maintain a record, by tax class, as follows: (a) The date, kind of wine, the number and size of bottle or... or destroyed, breakage, used for tasting. The volume recorded as bottled for bottle...

  7. Complexity in Surfaces of Densest Packings for Families of Polyhedra

    NASA Astrophysics Data System (ADS)

    Chen, Elizabeth R.; Klotsa, Daphne; Engel, Michael; Damasceno, Pablo F.; Glotzer, Sharon C.

    2014-01-01

    Packings of hard polyhedra have been studied for centuries due to their mathematical aesthetic and more recently for their applications in fields such as nanoscience, granular and colloidal matter, and biology. In all these fields, particle shape is important for structure and properties, especially upon crowding. Here, we explore packing as a function of shape. By combining simulations and analytic calculations, we study three two-parameter families of hard polyhedra and report an extensive and systematic analysis of the densest known packings of more than 55 000 convex shapes. The three families have the symmetries of triangle groups (icosahedral, octahedral, tetrahedral) and interpolate between various symmetric solids (Platonic, Archimedean, Catalan). We find optimal (maximum) packing-density surfaces that reveal unexpected richness and complexity, containing as many as 132 different structures within a single family. Our results demonstrate the importance of thinking about shape not as a static property of an object, in the context of packings, but rather as but one point in a higher-dimensional shape space whose neighbors in that space may have identical or markedly different packings. Finally, we present and interpret our packing results in a consistent and generally applicable way by proposing a method to distinguish regions of packings and classify types of transitions between them.

  8. 21 CFR 890.5730 - Moist heat pack.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Moist heat pack. 890.5730 Section 890.5730 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Therapeutic Devices § 890.5730 Moist heat pack....

  9. 46 CFR 160.043-6 - Marking and packing.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 6 2014-10-01 2014-10-01 false Marking and packing. 160.043-6 Section 160.043-6 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) EQUIPMENT, CONSTRUCTION, AND MATERIALS: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Jackknife (With Can Opener) for Merchant Vessels § 160.043-6 Marking and packing. (a)...

  10. 46 CFR 160.043-6 - Marking and packing.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 6 2012-10-01 2012-10-01 false Marking and packing. 160.043-6 Section 160.043-6 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) EQUIPMENT, CONSTRUCTION, AND MATERIALS: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Jackknife (With Can Opener) for Merchant Vessels § 160.043-6 Marking and packing. (a)...

  11. 14 CFR § 1214.605 - Preflight packing and storing.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 5 2014-01-01 2014-01-01 false Preflight packing and storing. § 1214.605 Section § 1214.605 Aeronautics and Space NATIONAL AERONAUTICS AND SPACE ADMINISTRATION SPACE FLIGHT Mementos Aboard Space Shuttle Flights § 1214.605 Preflight packing and storing. (a) Items intended...

  12. 14 CFR 1214.605 - Preflight packing and storing.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 5 2013-01-01 2013-01-01 false Preflight packing and storing. 1214.605 Section 1214.605 Aeronautics and Space NATIONAL AERONAUTICS AND SPACE ADMINISTRATION SPACE FLIGHT Mementos Aboard Space Shuttle Flights § 1214.605 Preflight packing and storing. (a) Items intended for...

  13. 14 CFR 1214.605 - Preflight packing and storing.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 5 2010-01-01 2010-01-01 false Preflight packing and storing. 1214.605 Section 1214.605 Aeronautics and Space NATIONAL AERONAUTICS AND SPACE ADMINISTRATION SPACE FLIGHT Mementos Aboard Space Shuttle Flights § 1214.605 Preflight packing and storing. (a) Items intended for...

  14. 14 CFR 1214.605 - Preflight packing and storing.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 5 2011-01-01 2010-01-01 true Preflight packing and storing. 1214.605 Section 1214.605 Aeronautics and Space NATIONAL AERONAUTICS AND SPACE ADMINISTRATION SPACE FLIGHT Mementos Aboard Space Shuttle Flights § 1214.605 Preflight packing and storing. (a) Items intended for...

  15. 14 CFR 1214.605 - Preflight packing and storing.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 5 2012-01-01 2012-01-01 false Preflight packing and storing. 1214.605 Section 1214.605 Aeronautics and Space NATIONAL AERONAUTICS AND SPACE ADMINISTRATION SPACE FLIGHT Mementos Aboard Space Shuttle Flights § 1214.605 Preflight packing and storing. (a) Items intended for...

  16. 48 CFR 1846.672-6 - Packing list instructions.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 6 2010-10-01 2010-10-01 true Packing list instructions. 1846.672-6 Section 1846.672-6 Federal Acquisition Regulations System NATIONAL AERONAUTICS AND SPACE ADMINISTRATION CONTRACT MANAGEMENT QUALITY ASSURANCE Material Inspection and Receiving Reports 1846.672-6 Packing list instructions. Copies of...

  17. On the kinetics of the pack - Aluminization process

    NASA Technical Reports Server (NTRS)

    Sivakumar, R.; Seigle, L. L.

    1976-01-01

    An investigation has been made of the aluminization of unalloyed Ni in fluoride-activated packs of varying Al activity. In packs of low Al activity, in which the ratio of Al to Ni was less than 50 at. pct, the specimen surface quickly came to equilibrium with the pack and remained close to equilibrium for the duration of normal coating runs. In these packs the kinetics of aluminization was controlled by diffusion in the solid. In packs of higher Al activity the surface of the specimen did not come to equilibrium with the pack and the kinetics of the process was governed by a combination of solid and gas diffusion rates. Under most conditions however, the surface composition was time-invariant and a steady-state appeared to exist at the pack-coating interface. By combining Levine and Caves' model for gaseous diffusion in pure-Al packs with calculations of solid diffusion rates some success has been achieved in explaining the results.

  18. 48 CFR 852.214-73 - Alternate packaging and packing.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 5 2011-10-01 2011-10-01 false Alternate packaging and....214-73 Alternate packaging and packing. As prescribed in 814.201-6(b)(3), insert the following provision: Alternate Packaging and Packing (JAN 2008) The bidder's offer must clearly indicate the...

  19. 48 CFR 852.214-73 - Alternate packaging and packing.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 5 2013-10-01 2013-10-01 false Alternate packaging and....214-73 Alternate packaging and packing. As prescribed in 814.201-6(b)(3), insert the following provision: Alternate Packaging and Packing (JAN 2008) The bidder's offer must clearly indicate the...

  20. 48 CFR 552.211-75 - Preservation, Packaging and Packing.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 4 2014-10-01 2014-10-01 false Preservation, Packaging....211-75 Preservation, Packaging and Packing. As prescribed in 511.204(b)(2), insert the following clause: Preservation, Packaging, and Packing (FEB 1996) Unless otherwise specified, all items shall...

  1. 48 CFR 852.214-73 - Alternate packaging and packing.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 5 2014-10-01 2014-10-01 false Alternate packaging and....214-73 Alternate packaging and packing. As prescribed in 814.201-6(b)(3), insert the following provision: Alternate Packaging and Packing (JAN 2008) The bidder's offer must clearly indicate the...

  2. 48 CFR 852.214-73 - Alternate packaging and packing.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 5 2012-10-01 2012-10-01 false Alternate packaging and....214-73 Alternate packaging and packing. As prescribed in 814.201-6(b)(3), insert the following provision: Alternate Packaging and Packing (JAN 2008) The bidder's offer must clearly indicate the...

  3. 48 CFR 552.211-75 - Preservation, Packaging and Packing.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 4 2012-10-01 2012-10-01 false Preservation, Packaging....211-75 Preservation, Packaging and Packing. As prescribed in 511.204(b)(2), insert the following clause: Preservation, Packaging, and Packing (FEB 1996) Unless otherwise specified, all items shall...

  4. 48 CFR 552.211-75 - Preservation, Packaging and Packing.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 4 2013-10-01 2013-10-01 false Preservation, Packaging....211-75 Preservation, Packaging and Packing. As prescribed in 511.204(b)(2), insert the following clause: Preservation, Packaging, and Packing (FEB 1996) Unless otherwise specified, all items shall...

  5. 48 CFR 852.214-73 - Alternate packaging and packing.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Alternate packaging and....214-73 Alternate packaging and packing. As prescribed in 814.201-6(b)(3), insert the following provision: Alternate Packaging and Packing (JAN 2008) The bidder's offer must clearly indicate the...

  6. 7 CFR 3201.85 - Packing and insulating materials.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 15 2013-01-01 2013-01-01 false Packing and insulating materials. 3201.85 Section... PROCUREMENT Designated Items § 3201.85 Packing and insulating materials. (a) Definition. Pre-formed and molded materials that are used to hold package contents in place during shipping or for insulating and...

  7. 7 CFR 3201.85 - Packing and insulating materials.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 15 2014-01-01 2014-01-01 false Packing and insulating materials. 3201.85 Section... PROCUREMENT Designated Items § 3201.85 Packing and insulating materials. (a) Definition. Pre-formed and molded materials that are used to hold package contents in place during shipping or for insulating and...

  8. 7 CFR 51.2927 - Marking and packing requirements.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... (INSPECTION, CERTIFICATION, AND STANDARDS) United States Standards for Grades of Apricots Marking and Packing Requirements § 51.2927 Marking and packing requirements. The minimum size or numerical count of the apricots in... diameter of the smallest apricot in the package. It shall be stated in terms of whole and eighth inches,...

  9. 7 CFR 51.2927 - Marking and packing requirements.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... STANDARDS) United States Standards for Grades of Apricots Marking and Packing Requirements § 51.2927 Marking and packing requirements. The minimum size or numerical count of the apricots in any package shall be... apricot in the package. It shall be stated in terms of whole and eighth inches, as 11/2 inches min.,...

  10. 7 CFR 51.2927 - Marking and packing requirements.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... STANDARDS) United States Standards for Grades of Apricots Marking and Packing Requirements § 51.2927 Marking and packing requirements. The minimum size or numerical count of the apricots in any package shall be... apricot in the package. It shall be stated in terms of whole and eighth inches, as 11/2 inches min.,...

  11. 7 CFR 51.2927 - Marking and packing requirements.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... STANDARDS) United States Standards for Grades of Apricots Marking and Packing Requirements § 51.2927 Marking and packing requirements. The minimum size or numerical count of the apricots in any package shall be... apricot in the package. It shall be stated in terms of whole and eighth inches, as 11/2 inches min.,...

  12. 7 CFR 51.2927 - Marking and packing requirements.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... (INSPECTION, CERTIFICATION, AND STANDARDS) United States Standards for Grades of Apricots Marking and Packing Requirements § 51.2927 Marking and packing requirements. The minimum size or numerical count of the apricots in... diameter of the smallest apricot in the package. It shall be stated in terms of whole and eighth inches,...

  13. 21 CFR 133.124 - Cold-pack cheese food.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Cold-pack cheese food. 133.124 Section 133.124 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION CHEESES AND RELATED CHEESE PRODUCTS Requirements for Specific Standardized Cheese and Related Products § 133.124 Cold-pack...

  14. Packed bed reactor for photochemical .sup.196 Hg isotope separation

    DOEpatents

    Grossman, Mark W.; Speer, Richard

    1992-01-01

    Straight tubes and randomly oriented pieces of tubing having been employed in a photochemical mercury enrichment reactor and have been found to improve the enrichment factor (E) and utilization (U) compared to a non-packed reactor. One preferred embodiment of this system uses a moving bed (via gravity) for random packing.

  15. 8. Photographic copy of photograph, Parachute Packing Room, ca. 1932, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    8. Photographic copy of photograph, Parachute Packing Room, ca. 1932, in possession of Selfridge Base Museum (Historic Photograph File; location of original negative), Mt. Clemens, Michigan. NORTHEAST VIEW, PACKING ROOM WITH PARACHUTES - Selfridge Field, Building No. 121, Wilbur Wright Avenue west of Ash Street, Mount Clemens, Macomb County, MI

  16. The effect of nanoparticle packing on capacitive electrode performance

    NASA Astrophysics Data System (ADS)

    Lee, Younghee; Noh, Seonmyeong; Kim, Min-Sik; Kong, Hye Jeong; Im, Kyungun; Kwon, Oh Seok; Kim, Sungmin; Yoon, Hyeonseok

    2016-06-01

    Nanoparticles pack together to form macro-scale electrodes in various types of devices, and thus, optimization of the nanoparticle packing is a prerequisite for the realization of a desirable device performance. In this work, we provide in-depth insight into the effect of nanoparticle packing on the performance of nanoparticle-based electrodes by combining experimental and computational findings. As a model system, polypyrrole nanospheres of three different diameters were used to construct pseudocapacitive electrodes, and the performance of the electrodes was examined at various nanosphere diameter ratios and mixed weight fractions. Two numerical algorithms are proposed to simulate the random packing of the nanospheres on the electrode. The binary nanospheres exhibited diverse, complicated packing behaviors compared with the monophasic packing of each nanosphere species. The packing of the two nanosphere species with lower diameter ratios at an optimized composition could lead to more dense packing of the nanospheres, which in turn could contribute to better device performance. The dense packing of the nanospheres would provide more efficient transport pathways for ions because of the reduced inter-nanosphere pore size and enlarged surface area for charge storage. Ultimately, it is anticipated that our approach can be widely used to define the concept of ``the best nanoparticle packing'' for desirable device performance.Nanoparticles pack together to form macro-scale electrodes in various types of devices, and thus, optimization of the nanoparticle packing is a prerequisite for the realization of a desirable device performance. In this work, we provide in-depth insight into the effect of nanoparticle packing on the performance of nanoparticle-based electrodes by combining experimental and computational findings. As a model system, polypyrrole nanospheres of three different diameters were used to construct pseudocapacitive electrodes, and the performance of the

  17. Vacuum skin pack of beef--a consumer friendly alternative.

    PubMed

    Lagerstedt, Åsa; Ahnström, Maria L; Lundström, Kerstin

    2011-07-01

    The aim of this study was to assess how beef quality traits are affected by skin packaging compared with vacuum and high-oxygen modified atmosphere packaging (MAP; 80% O(2) and 20% CO(2)). Both M. longissimus dorsi from 6 young bulls were cut and aged in vacuum for 7 days and then cut into 3.5-cm steaks, thereafter either frozen directly day 7 or stored in skin pack, vacuum pack or MAP for an additional 7 or 14 days and then frozen. Warner-Bratzler shear force, loss and colour were measured and sensory analysis was performed. The results showed no differences in shear force, sensory analysis and total loss between steaks packed in skin pack or vacuum, but skin packed steaks had lower purge loss. MAP steaks had lower sensory scores than the other treatments at days 14 and 21. Raw MAP-steaks were bright red, but showed signs of premature browning when cooked. PMID:21316869

  18. Statistical theory of correlations in random packings of hard particles.

    PubMed

    Jin, Yuliang; Puckett, James G; Makse, Hernán A

    2014-05-01

    A random packing of hard particles represents a fundamental model for granular matter. Despite its importance, analytical modeling of random packings remains difficult due to the existence of strong correlations which preclude the development of a simple theory. Here, we take inspiration from liquid theories for the n-particle angular correlation function to develop a formalism of random packings of hard particles from the bottom up. A progressive expansion into a shell of particles converges in the large layer limit under a Kirkwood-like approximation of higher-order correlations. We apply the formalism to hard disks and predict the density of two-dimensional random close packing (RCP), ϕ(rcp) = 0.85 ± 0.01, and random loose packing (RLP), ϕ(rlp) = 0.67 ± 0.01. Our theory also predicts a phase diagram and angular correlation functions that are in good agreement with experimental and numerical data. PMID:25353787

  19. Multilayer DNA origami packed on hexagonal and hybrid lattices.

    PubMed

    Ke, Yonggang; Voigt, Niels V; Gothelf, Kurt V; Shih, William M

    2012-01-25

    "Scaffolded DNA origami" has been proven to be a powerful and efficient approach to construct two-dimensional or three-dimensional objects with great complexity. Multilayer DNA origami has been demonstrated with helices packing along either honeycomb-lattice geometry or square-lattice geometry. Here we report successful folding of multilayer DNA origami with helices arranged on a close-packed hexagonal lattice. This arrangement yields a higher density of helical packing and therefore higher resolution of spatial addressing than has been shown previously. We also demonstrate hybrid multilayer DNA origami with honeycomb-lattice, square-lattice, and hexagonal-lattice packing of helices all in one design. The availability of hexagonal close-packing of helices extends our ability to build complex structures using DNA nanotechnology. PMID:22187940

  20. Avoidance of Cigarette Pack Health Warnings among Regular Cigarette Smokers

    PubMed Central

    Maynard, Olivia M.; Attwood, Angela; O’Brien, Laura; Brooks, Sabrina; Hedge, Craig; Leonards, Ute; Munafò, Marcus R.

    2016-01-01

    Background Previous research with adults and adolescents indicates that plain cigarette packs increase visual attention to health warnings among non-smokers and non-regular smokers, but not among regular smokers. This may be because regular smokers: 1) are familiar with the health warnings, 2) preferentially attend to branding, or 3) actively avoid health warnings. We sought to distinguish between these explanations using eye-tracking technology. Method A convenience sample of 30 adult dependant smokers were recruited to participate in an eye-tracking study. Participants viewed branded, plain and blank packs of cigarettes with familiar and unfamiliar health warnings. The number of fixations to health warnings and branding on the different pack types were recorded. Results Analysis of variance indicated that regular smokers were biased towards fixating the branding location rather than the health warning location on all three pack types (p < 0.002). This bias was smaller, but still evident, for blank packs, where smokers preferentially attended the blank region over the health warnings. Time-course analysis showed that for branded and plain packs, attention was preferentially directed to the branding location for the entire 10 seconds of the stimulus presentation, while for blank packs this occurred for the last 8 seconds of the stimulus presentation. Familiarity with health warnings had no effect on eye gaze location. Conclusion Smokers actively avoid cigarette pack health warnings, and this remains the case even in the absence of salient branding information. Smokers may have learned to divert their attention away from cigarette pack health warnings. These findings have policy implications for the design of health warning on cigarette packs. PMID:24485554

  1. Packing regularities in biological structures relate to their dynamics.

    PubMed

    Jernigan, Robert L; Kloczkowski, Andrzej

    2007-01-01

    The high packing density inside proteins leads to certain geometric regularities and also is one of the most important contributors to the high extent of cooperativity manifested by proteins in their cohesive domain motions. The orientations between neighboring nonbonded residues in proteins substantially follow the similar geometric regularities, regardless of whether the residues are on the surface or buried, a direct result of hydrophobicity forces. These orientations are relatively fixed and correspond closely to small deformations from those of the face-centered cubic lattice, which is the way in which identical spheres pack at the highest density. Packing density also is related to the extent of conservation of residues, and we show this relationship for residue packing densities by averaging over a large sample or residue packings. There are three regimes: (1) over a broad range of packing densities the relationship between sequence entropy and inverse packing density is nearly linear, (2) over a limited range of low packing densities the sequence entropy is nearly constant, and (3) at extremely low packing densities the sequence entropy is highly variable. These packing results provide important justification for the simple elastic network models that have been shown for a large number of proteins to represent protein dynamics so successfully, even when the models are extremely coarse grained. Elastic network models for polymeric chains are simple and could be combined with these protein elastic networks to represent partially denatured parts of proteins. Finally, we show results of applications of the elastic network model to study the functional motions of the ribosome, based on its known structure. These results indicate expected correlations among its components for the step-wise processing steps in protein synthesis, and suggest ways to use these elastic network models to develop more detailed mechanisms, an important possibility because most

  2. Fluid flow through packings of rotating obstacles

    NASA Astrophysics Data System (ADS)

    Oliveira, Rafael S.; Andrade, José S.; Andrade, Roberto F. S.

    2015-03-01

    We investigate through numerical simulation the nonstationary flow of a Newtonian fluid through a two-dimensional channel filled with an array of circular obstacles of distinct sizes. The disks may rotate around their respective centers, modeling a nonstationary, inhomogeneous porous medium. Obstacle sizes and positions are defined by the geometry of an Apollonian packing (AP). To allow for fluid flow, the radii of the disks are uniformly reduced by a factor 0.6 ≤s ≤0.8 for assemblies corresponding to the four first AP generations. The investigation is targeted to elucidate the main features of the rotating regime as compared to the fixed disk condition. It comprises the evaluation of the region of validity of Darcy's law as well as the study of the nonlinear hydraulic resistance as a function of the channel Reynolds number, the reduction factor s , and the AP generation. Depending on a combination of these factors, the resistance of rotating disks may be larger or smaller than that of the corresponding static case. We also analyze the flow redistribution in the interdisk channels as a result of the rotation pattern and characterize the angular velocity of the disks. Here, the striking feature is the emergence of a stable oscillatory behavior of the angular velocity for almost all disks that are inserted into the assemblies after the second generation.

  3. [Diagnosis and treatment of 'body packer' syndrome].

    PubMed

    Henebiens, M; van Geloven, A A W; Gouma, D J

    2007-08-25

    A body packer is someone who carries drugs such as heroine or cocaine, packed in rubber or plastic, in his/her body in order to smuggle them. These people can present with symptoms that vary from mild abdominal complaints to respiratory insufficiency and even death. Physical examination and additional radiology tests are helpful for the diagnosis. Any packages can usually be seen on a plain abdominal X-ray. Detailed information on the number of drug packages, their exact location in the gastrointestinal tract and complications, such as small intestine obstruction or perforation, can be derived from a CT scan. In most patients conservative treatment suffices. Surgery for body packing, i.e. the removal of the packages by gastrotomy or enterotomy, is often followed by serious complications related to contamination of the peritoneum that frequently occurs. PMID:17902559

  4. Do gray wolves (Canis lupus) support pack mates during aggressive inter-pack interactions?

    PubMed

    Cassidy, Kira A; McIntyre, Richard T

    2016-09-01

    For group-living mammals, social coordination increases success in everything from hunting and foraging (Crofoot and Wrangham in Mind the Gap, Springer, Berlin, 2010; Bailey et al. in Behav Ecol Sociobiol 67:1-17, 2013) to agonism (Mosser and Packer in Anim Behav 78:359-370, 2009; Wilson et al. in Anim Behav 83:277-291, 2012; Cassidy et al. in Behav Ecol 26:1352-1360, 2015). Cooperation is found in many species and, due to its low costs, likely is a determining factor in the evolution of living in social groups (Smith in Anim Behav 92:291-304, 2014). Beyond cooperation, many mammals perform costly behaviors for the benefit of group mates (e.g., parental care, food sharing, grooming). Altruism is considered the most extreme case of cooperation where the altruist increases the fitness of the recipient while decreasing its own fitness (Bell in Selection: the mechanism of evolution. Oxford University Press, Oxford 2008). Gray wolf life history requires intra-pack familiarity, communication, and cooperation in order to succeed in hunting (MacNulty et al. in Behav Ecol doi: 10.1093/beheco/arr159 2011) and protecting group resources (Stahler et al. in J Anim Ecol 82: 222-234, 2013; Cassidy et al. in Behav Ecol 26:1352-1360, 2015). Here, we report 121 territorial aggressive inter-pack interactions in Yellowstone National Park between 1 April 1995 and 1 April 2011 (>5300 days of observation) and examine each interaction where one wolf interferes when its pack mate is being attacked by a rival group. This behavior was recorded six times (17.6 % of interactions involving an attack) and often occurred between dyads of closely related individuals. We discuss this behavior as it relates to the evolution of cooperation, sociality, and altruism. PMID:27193460

  5. Complexity in surfaces of densest packings for families of polyhedra

    NASA Astrophysics Data System (ADS)

    Klotsa, Daphne; Chen, Elizabeth R.; Engel, Michael; Damasceno, Pablo F.; Glotzer, Sharon C.

    2014-03-01

    Packings of hard polyhedra have been studied for centuries due to their mathematical aesthetic and more recently for their applications in fields such as nanoscience, colloidal matter, and biology. In all these fields, particle shape is important for structure and properties, especially upon crowding. In this talk, we explore packing as a function of shape. By combining simulations and analytic calculations, we study three 2-parameter families of hard polyhedra and report an extensive and systematic analysis of the densest known packings of more than 55,000 convex shapes. The three families have the symmetries of triangle groups (20-hedral, 8-hedral, 4-hedral) and interpolate between various symmetric solids (Platonic, Archimedean, Catalan). We find that maximum packing density surfaces reveal unexpected richness and complexity, containing as many as 130 different structures within a single family. Our results demonstrate the importance of thinking about shape not as a static property of an object, in the context of packings, but rather as but one point in a higher dimensional shape space whose neighbors in that space may have identical or markedly different packings. Finally, we propose a method to distinguish regions of packings and classify types of transitions between them.

  6. Wellbore pressure differential control for gravel pack screen

    SciTech Connect

    Cornette, H.M.

    1993-08-10

    A method is described for minimizing cross-flow of fluid in a wellbore in an earth formation and fitted with a gravel packing and an auger-type gravel pack screen, comprising the steps of: providing an auger-type gravel pack screen having a generally tubular liner member defining a space therewithin; providing a quantity of wellbore fluid loss control material comprising a graded particulate salt disposed in said space which will provide a substantially impermeable barrier to the flow of fluid out of said space through said liner into said gravel packing and said earth formation; filling at least a portion of said space with said material; installing said screen in said gravel packing; removing said material from said space after installation of said screen in said gravel packing by entraining said material in a carrier fluid while allowing at least some of said material to flow out of said space through said screen to form a filter cake on at least one of said gravel packing and said earth formation to minimize said cross-flow of fluid into said earth formation.

  7. PackBot: a versatile platform for military robotics

    NASA Astrophysics Data System (ADS)

    Yamauchi, Brian M.

    2004-09-01

    The iRobot PackBot is a combat-tested, man-portable UGV that has been deployed in Afghanistan and Iraq. The PackBot is also a versatile platform for mobile robotics research and development that supports a wide range of payloads suitable for many different mission types. In this paper, we describe four R&D projects that developed experimental payloads and software using the PackBot platform. CHARS was a rapid development project to develop a chemical/radiation sensor for the PackBot. We developed the CHARS payload in six weeks and deployed it to Iraq to search for chemical and nuclear weapons. Griffon was a research project to develop a flying PackBot that combined the capabilities of a UGV and a UAV. We developed a Griffon prototype equipped with a steerable parafoil and gasoline-powered motor, and we completed successful flight tests including remote-controlled launch, ascent, cruising, descent, and landing. Valkyrie is an ongoing research and development project to develop a PackBot payload that will assist medics in retrieving casualties from the battlefield. Wayfarer is an applied research project to develop autonomous urban navigation capabilities for the PackBot using laser, stereo vision, GPS, and INS sensors.

  8. Body Measurement.

    ERIC Educational Resources Information Center

    Neufeld, K. Allen

    1989-01-01

    Described are activities for measuring the human body. The activities include measurements and calculations, calculating volume and density, problems related to body measurement, and using a nomogram. Several charts, illustrations, and a nomogram are provided. (YP)

  9. Enabling Microliquid Chromatography by Microbead Packing of Microchannels

    NASA Technical Reports Server (NTRS)

    Balvin, Manuel; Zheng, Yun

    2013-01-01

    The microbead packing is the critical element required in the success of on-chip microfabrication of critical microfluidic components for in-situ analysis and detection of chiral amino acids. In order for microliquid chromatography to occur, there must be a stationary phase medium within the microchannel that interacts with the analytes present within flowing fluid. The stationary phase media are the microbeads packed by the process discussed in this work. The purpose of the microliquid chromatography is to provide a lightweight, low-volume, and low-power element to separate amino acids and their chiral partners efficiently to understand better the origin of life. In order to densely pack microbeads into the microchannels, a liquid slurry of microbeads was created. Microbeads were extracted from a commercially available high-performance liquid chromatography column. The silica beads extracted were 5 microns in diameter, and had surface coating of phenyl-hexyl. These microbeads were mixed with a 200- proof ethanol solution to create a microbead slurry with the right viscosity for packing. A microfilter is placed at the outlet via of the microchannel and the slurry is injected, then withdrawn across a filter using modified syringes. After each injection, the channel is flushed with ethanol to enhance packing. This cycle is repeated numerous times to allow for a tightly packed channel of microbeads. Typical microbead packing occurs in the macroscale into tubes or channels by using highly pressurized systems. Moreover, these channels are typically long and straight without any turns or curves. On the other hand, this method of microbead packing is completed within a microchannel 75 micrometers in diameter. Moreover, the microbead packing is completed into a serpentine type microchannel, such that it maximizes microchannel length within a microchip. Doing so enhances the interactions of the analytes with the microbeads to separate efficiently amino acids and amino acid

  10. Enabling Microliquid Chromatography by Microbead Packing of Microchannels

    NASA Technical Reports Server (NTRS)

    Balvin, Manuel; Zheng, Yun

    2014-01-01

    The microbead packing is the critical element required in the success of on-chip microfabrication of critical microfluidic components for in-situ analysis and detection of chiral amino acids. In order for microliquid chromatography to occur, there must be a stationary phase medium within the microchannel that interacts with the analytes present within flowing fluid. The stationary phase media are the microbeads packed by the process discussed in this work. The purpose of the microliquid chromatography is to provide a lightweight, low-volume, and low-power element to separate amino acids and their chiral partners efficiently to understand better the origin of life. In order to densely pack microbeads into the microchannels, a liquid slurry of microbeads was created. Microbeads were extracted from a commercially available high-performance liquid chromatography column. The silica beads extracted were 5 microns in diameter, and had surface coating of phenyl-hexyl. These microbeads were mixed with a 200- proof ethanol solution to create a microbead slurry with the right viscosity for packing. A microfilter is placed at the outlet via of the microchannel and the slurry is injected, then withdrawn across a filter using modified syringes. After each injection, the channel is flushed with ethanol to enhance packing. This cycle is repeated numerous times to allow for a tightly packed channel of microbeads. Typical microbead packing occurs in the macroscale into tubes or channels by using highly pressurized systems. Moreover, these channels are typically long and straight without any turns or curves. On the other hand, this method of microbead packing is completed within a microchannel 75 micrometers in diameter. Moreover, the microbead packing is completed into a serpentine type microchannel, such that it maximizes microchannel length within a microchip. Doing so enhances the interactions of the analytes with the microbeads to separate efficiently amino acids and amino acid

  11. Matched particle/liquid density well packing technique

    SciTech Connect

    Copeland, C.T.

    1988-03-29

    A method of packing a well, a portion of which penetrates an earth formation at an angle to the vertical is described comprising: (a) injecting into the wellbore a slurry of particles in a liquid, the slurry having a particle density to liquid density ratio of no greater than about 2 to 1, and the particles having a coating of adhesive; and (b) straining the particles out of the slurry so as to produce a packed mass of the particles adjacent the formation, which packed mass will allow flow of fluids between the formation and wellbore, while substantially preventing particulate material from the formation passing therethrough and into the wellbore.

  12. Ultratight crystal packing of a 10 kDa protein

    SciTech Connect

    Trillo-Muyo, Sergio; Chruszcz, Maksymilian; Minor, Wladek; Kuisiene, Nomeda

    2013-03-01

    The crystal structure of the C-terminal domain of a putative U32 peptidase from G. thermoleovorans is reported; it is one of the most tightly packed protein structures reported to date. While small organic molecules generally crystallize forming tightly packed lattices with little solvent content, proteins form air-sensitive high-solvent-content crystals. Here, the crystallization and full structure analysis of a novel recombinant 10 kDa protein corresponding to the C-terminal domain of a putative U32 peptidase are reported. The orthorhombic crystal contained only 24.5% solvent and is therefore among the most tightly packed protein lattices ever reported.

  13. Contact nonlinearities and linear response in jammed particulate packings.

    PubMed

    Goodrich, Carl P; Liu, Andrea J; Nagel, Sidney R

    2014-08-01

    Packings of frictionless athermal particles that interact only when they overlap experience a jamming transition as a function of packing density. Such packings provide the foundation for the theory of jamming. This theory rests on the observation that, despite the multitude of disordered configurations, the mechanical response to linear order depends only on the distance to the transition. We investigate the validity and utility of such measurements that invoke the harmonic approximation and show that, despite particles coming in and out of contact, there is a well-defined linear regime in the thermodynamic limit. PMID:25215727

  14. STABILITY OF SATELLITES IN CLOSELY PACKED PLANETARY SYSTEMS

    SciTech Connect

    Payne, Matthew J.; Holman, Matthew J.; Deck, Katherine M.; Perets, Hagai B.

    2013-10-01

    We perform numerical integrations of four-body (star, planet, planet, satellite) systems to investigate the stability of satellites in planetary systems with tightly packed inner planets (STIPs). We find that the majority of closely spaced stable two-planet systems can stably support satellites across a range of parameter-space which is only slightly decreased compared to that seen for the single-planet case. In particular, circular prograde satellites remain stable out to ∼0.4 R{sub H} (where R{sub H} is the Hill radius) as opposed to 0.5 R{sub H} in the single-planet case. A similarly small restriction in the stable parameter-space for retrograde satellites is observed, where planetary close approaches in the range 2.5-4.5 mutual Hill radii destabilize most satellites orbits only if a ∼ 0.65 R{sub H} . In very close planetary pairs (e.g., the 12:11 resonance) the addition of a satellite frequently destabilizes the entire system, causing extreme close approaches and the loss of satellites over a range of circumplanetary semi-major axes. The majority of systems investigated stably harbored satellites over a wide parameter-space, suggesting that STIPs can generally offer a dynamically stable home for satellites, albeit with a slightly smaller stable parameter-space than the single-planet case. As we demonstrate that multi-planet systems are not a priori poor candidates for hosting satellites, future measurements of satellite occurrence rates in multi-planet systems versus single-planet systems could be used to constrain either satellite formation or past periods of strong dynamical interaction between planets.

  15. Structural Evolution of a Granular Pack under Manual Tapping

    NASA Astrophysics Data System (ADS)

    Iikawa, Naoki; Bandi, Mahesh M.; Katsuragi, Hiroaki

    2015-09-01

    We experimentally study a two-dimensional (2D) granular pack of photoelastic disks subject to vertical manual tapping. Using bright- and dark-field images, we employ gradient-based image analysis methods to analyze various structural quantities. These include the packing fraction (ϕ), force per disk (Fd), and force chain segment length (l) as functions of the tapping number (τ). The increase in the packing fraction with the tapping number is found to exponentially approach an asymptotic value. An exponential distribution is observed for the cumulative numbers of both the force per disk Fd:Ncum(Fd) = AFexp ( - Fd/F0), and the force chain segment length l:Ncum(l) = Alexp ( - l/l0). Whereas the coefficient AF varies with τ for Fd, l shows no dependence on τ. The τ dependences of Fd and ϕ allow us to posit a linear relationship between the total force of the granular pack Ftot*(τ ) and ϕ(τ).

  16. Ice pack heat sink subsystem - phase 1, volume 2

    NASA Technical Reports Server (NTRS)

    Roebelen, G. J., Jr.

    1973-01-01

    The design, development, and test of a functional laboratory model ice pack heat sink subsystem are discussed. Operating instructions to include mechanical and electrical schematics, maintenance instructions, and equipment specifications are presented.

  17. Ice pack heat sink subsystem - Phase 1, Volume 1

    NASA Technical Reports Server (NTRS)

    Roebelen, G. J., Jr.

    1973-01-01

    The design, development, fabrication, and test at one-g of a functional laboratory model (non-flight) ice pack heat sink subsystem to be used eventually for astronaut cooling during manned space missions are discussed. In normal use, excess heat in the liquid cooling garment (LCG) coolant is transferred to a reusable/regenerable ice pack heat sink. For emergency operation, or for extension of extravehicular activity mission time after all the ice has melted, water from the ice pack is boiled to vacuum, thereby continuing to remove heat from the LCG coolant. This subsystem incorporates a quick connect/disconnect thermal interface between the ice pack heat sink and the subsystem heat exchanger.

  18. Three dimensional imaging of soft sphere packings under shear

    NASA Astrophysics Data System (ADS)

    Behringer, Robert; Dijksman, Joshua; Sia, Eric

    2011-11-01

    The (microscopic) flow of three dimensional disordered athermal granular packings remains poorly understood. However, experimentally studying flow and deformations in a three dimensional packing of grains is challenging due to the opacity of such packings. Our goal is to study triaxial shear of granular materials, using refractive index matched scanning. We will present results on a study of the deformation of a three dimensional soft sphere packing under quasi static compression. The spheres are made from hydrogel and virtually frictionless, similar to the study by by Mukhopadhyay et. al. (2011). We track particles and image contact deformations, and look at the effect of cyclic shear flow. NSF-DMR0906908, ARO-W911NF-11-1-0110.

  19. 8. HIGH POWER SPRAY IN MEN'S PACK ROOM. Hot ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    8. HIGH POWER SPRAY IN MEN'S PACK ROOM. - Hot Springs National Park Bathhouse Row, Maurice Bathhouse: Mechanical & Piping Systems, State Highway 7, 1 mile north of U.S. Highway 70, Hot Springs, Garland County, AR

  20. 9. NEEDLE SHOWER IN MEN'S PACK ROOM. Hot Springs ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    9. NEEDLE SHOWER IN MEN'S PACK ROOM. - Hot Springs National Park Bathhouse Row, Maurice Bathhouse: Mechanical & Piping Systems, State Highway 7, 1 mile north of U.S. Highway 70, Hot Springs, Garland County, AR

  1. Uterovaginal Packing With Rolled Gauze in Postpartum Hemorrhage

    PubMed Central

    Bagga, Rashmi; Jain, Vanita; Chopra, Seema; Kalra, Jasvinder; Gopalan, Sarala

    2004-01-01

    Management options for postpartum hemorrhage (PPH) include oxytocics, prostaglandins, genital tract exploration, ligation or angiographic embolization of uterine/internal iliac arteries, and hysterectomy. After excluding uterine rupture, genital tract lacerations, and retained placental tissue, efforts are directed toward contracting the uterus by bimanual compression and oxytocics. If these are not successful, one must resort to surgical techniques. At this stage, an alternative option to remember is uterovaginal packing. Easy and quick to perform, it may be used to control bleeding by tamponade effect and stabilize the patient until a surgical procedure is arranged. Uterovaginal packing may sometimes obviate the need for surgery altogether. Two cases, a primary and a secondary PPH, managed recently with uterovaginal packing are reported. Despite concerns about concealed hemorrhage or the development of infection with this intervention, none of these problems were encountered, and uterine packing was successful even in the case of secondary PPH with documented infection. PMID:15208561

  2. 15. STOCKHAM PACKED SMALL FITTINGS IN BARRELS AND, AS EARLY ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    15. STOCKHAM PACKED SMALL FITTINGS IN BARRELS AND, AS EARLY AS 1919, TRANSPORTED THEM IN THEIR OWN PACKARD DELIVERY TRUCKS. - Stockham Pipe & Fittings Company, 4000 Tenth Avenue North, Birmingham, Jefferson County, AL

  3. 48 CFR 552.211-87 - Export packing.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...) Offerors are requested to quote, in the pricelist accompanying their offer (or by separate attachment... specifications describing the packing to be furnished at the price quoted. (b) Ordering activities will not...

  4. 48 CFR 552.211-87 - Export packing.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...) Offerors are requested to quote, in the pricelist accompanying their offer (or by separate attachment... specifications describing the packing to be furnished at the price quoted. (b) Ordering activities will not...

  5. 36. ORCHARD LINE, LOOKING SOUTH, SHOWING PACIFIC FRUIT PACKING HOUSE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    36. ORCHARD LINE, LOOKING SOUTH, SHOWING PACIFIC FRUIT PACKING HOUSE NEAR END OF LINE - Yakima Valley Transportation Company Interurban Railroad, Connecting towns of Yakima, Selah & Wiley City, Yakima, Yakima County, WA

  6. Colloquium: Geometry and optimal packing of twisted columns and filaments

    NASA Astrophysics Data System (ADS)

    Grason, Gregory M.

    2015-04-01

    This Colloquium presents recent progress in understanding constraints and consequences of close-packing geometry of filamentous or columnar materials possessing nontrivial textures, focusing, in particular, on the common motifs of twisted and toroidal structures. The mathematical framework is presented that relates spacing between linelike, filamentous elements to their backbone orientations, highlighting the explicit connection between the interfilament metric properties and the geometry of non-Euclidean surfaces. The consequences of the hidden connection between packing in twisted filament bundles and packing on positively curved surfaces, like the Thomson problem, are demonstrated for the defect-riddled ground states of physical models of twisted filament bundles. The connection between the "ideal" geometry of fibrations of curved three-dimensional space, including the Hopf fibration, and the non-Euclidean constraints of filament packing in twisted and toroidal bundles is presented, with a focus on the broader dependence of metric geometry on the simultaneous twisting and folding of multifilament bundles.

  7. Mathematical model partitioning and packing for parallel computer calculation

    NASA Technical Reports Server (NTRS)

    Arpasi, Dale J.; Milner, Edward J.

    1986-01-01

    This paper deals with the development of multiprocessor simulations from a serial set of ordinary differential equations describing a physical system. The identification of computational parallelism within the model equations is discussed. A technique is presented for identifying this parallelism and for partitioning the equations for parallel solution on a multiprocessor. Next, an algorithm which packs the equations into a minimum number of processors is described. The results of applying the packing algorithm to a turboshaft engine model are presented.

  8. Consideration of grain packing in granular iron treatability studies.

    PubMed

    Firdous, R; Devlin, J F

    2014-08-01

    Commercial granular iron (GI) is light steel that is used in Permeable Reactive Barriers (PRBs). Investigations into the reactivity of GI have focused on its chemical nature and relatively little direct work has been done to account for the effects of grain shape and packing. Both of these factors are expected to influence available grain surface area, which is known to correlate to reactivity. Commercial granular iron grains are platy and therefore pack in preferential orientations that could affect solution access to the surface. Three packing variations were investigated using Connelly Iron and trichloroethylene (TCE). Experimental kinetic data showed reaction rates 2-4 times higher when grains were packed with long axes preferentially parallel to flow (VP) compared to packings with long axes preferentially perpendicular to flow (HP) or randomly arranged (RP). The variations were found to be explainable by variations in reactive sorption capacities, i.e., sorption to sites where chemical transformations took place. The possibility that the different reactive sorption capacities were related to physical pore-scale differences was assessed by conducting an image analysis of the pore structure of sectioned columns. The analyses suggested that pore-scale factors - in particular the grain surface availability, reflected in the sorption capacity terms of the kinetic model used - could only account for a fraction of the observed reactivity differences between packing types. It is concluded that packing does affect observable reaction rates but that micro-scale features on the grain surfaces, rather than the pore scale characteristics, account for most of the apparent reactivity differences. This result suggests that treatability tests should consider the packing of columns carefully if they are to mimic field performance of PRBs to the greatest extent possible. PMID:25005796

  9. A SAT Encoding for Multi-dimensional Packing Problems

    NASA Astrophysics Data System (ADS)

    Grandcolas, Stéphane; Pinto, Cédric

    The Orthogonal Packing Problem (OPP) consists in determining if a set of items can be packed into a given container. This decision problem is NP-complete. Fekete et al. modelled the problem in which the overlaps between the objects in each dimension are represented by interval graphs. In this paper we propose a SAT encoding of Fekete et al. characterization. Some results are presented, and the efficiency of this approach is compared with other SAT encodings.

  10. Packing fraction and compaction dynamics of magnetic powders

    NASA Astrophysics Data System (ADS)

    Lumay, G.; Vandewalle, N.

    2009-06-01

    We have investigated experimentally the influence of magnetic interactions between the grains (i) on the packing fraction and (ii) on the compaction dynamics of a granular pile. The granular material used to perform these studies is made of ferromagnetic grains submitted to an external magnetic field B⃗. The evolution of the packing fraction as a function of the Bond number Bo witch is the ratio between the cohesive force Fc and the grain weight mg has been measured. Moreover, we present an experimental protocol that allows one to tune the packing fraction η of a random pile of ferromagnetic spheres from a value close to the lower limit of random loose packing ηRLP≃0.56 to the upper limit of random close packing ηRCP≃0.64. This broad range of packing fraction values are obtained under normal gravity in air, by using a magnetic cohesion between the grains during the initialization of the pile. Concerning the compaction dynamics, the influence of the magnetic interaction on the compaction characteristic time τ has been measured.

  11. Granular flow through an aperture: influence of the packing fraction.

    PubMed

    Aguirre, M A; De Schant, R; Géminard, J-C

    2014-07-01

    For the last 50 years, the flow of a granular material through an aperture has been intensely studied in gravity-driven vertical systems (e.g., silos and hoppers). Nevertheless, in many industrial applications, grains are horizontally transported at constant velocity, lying on conveyor belts or floating on the surface of flowing liquids. Unlike fluid flows, that are controlled by the pressure, granular flow is not sensitive to the local pressure but rather to the local velocity of the grains at the outlet. We can also expect the flow rate to depend on the local density of the grains. Indeed, vertical systems are packed in dense configurations by gravity, but, in contrast, in horizontal systems the density can take a large range of values, potentially very small, which may significantly alter the flow rate. In the present article, we study, for different initial packing fractions, the discharge through an orifice of monodisperse grains driven at constant velocity by a horizontal conveyor belt. We report how, during the discharge, the packing fraction is modified by the presence of the outlet, and we analyze how changes in the packing fraction induce variations in the flow rate. We observe that variations of packing fraction do not affect the velocity of the grains at the outlet, and, therefore, we establish that flow-rate variations are directly related to changes in the packing fraction. PMID:25122295

  12. Matched particle/liquid density well packing technique

    SciTech Connect

    Copeland, C.T.; Gurley, D.G.

    1989-07-25

    This patent describes a method of packing a well. It comprises: injecting into the wellbore a slurry of particles in a liquid, the slurry having a (particle density to liquid density ratio of no greater than about 2to 1), and the particles being substantially free of surface adhesive; and straining the particles out of the slurry so as to produce a packed mass of the particles adjacent the formation, which packed mass will allow flow of fluids therethrough between the formation and wellbore, while substantially preventing particulate material from the formation passing therethrough and into the wellbore. This patent describes a method of packing a well a portion of the bore of which penetrates an earth formation at an angle to the vertical of greater than 45{sup 0}. It comprises: injection into the wellbore a slurry of particles in a liquid, the slurry having a particle density to liquid density ratio of no greater than about 2 to 1, and the particles being substantially free of surface adhesive, having a density of between about 0.8 to about 1.2, and having a Krumbein roundness and sphericity of at least about 0.6; straining the particles out of the slurry so as to produce a packed mass of the particles at that portion of the well, which packed mass will allow production of fluids therethrough from the formation into the wellbore, while substantially preventing particulate material from the formation passing therethrough and into the wellbore during such production.

  13. Pack aluminization of nickel anode for molten carbonate fuel cells

    NASA Astrophysics Data System (ADS)

    Chun, H. S.; Park, G. P.; Lim, J. H.; Kim, K.; Lee, J. K.; Moon, K. H.; Youn, J. H.

    1994-04-01

    The aluminum pack cementation (pack aluminization) process on a porous nickel anode for molten carbonate fuel cells has been studied to improve anode creep resistance. The porous nickel substrates used in this study were fabricated by doctor blade equipment followed by sintering (850 C). Packs surrounding the Ni anode were made by mixing Al2O3 powder, Al powder, and NaCl as activator. The pack aluminization was performed at 700 to 850 C for 0.5-5.0 h. After pack aluminization, the principal Ni-Al intermetallic compounds detected were Ni3Al at 700 C, NiAl at 750 C and Ni3Al2 at 800 C. The aluminum content in the aluminized Ni anode was proportional to the square root of pack aluminizing time. With increasing the Al content in the anode, the creep of the anode decreased. It was nearly constant (2.0%) when the Al content was above 5.0%. Although the exchange current density (24 mA/sq cm) for the aluminized (2.5 wt.%) Ni anode was somewhat lower than that of the pure Ni anode (40 mA/sq cm), the performance of a single cell using an aluminized Ni anode was similar to that of the one with pure Ni anode.

  14. Bernal random loose packing through freeze-thaw cycling

    NASA Astrophysics Data System (ADS)

    Ludewig, F.; Vandewalle, N.; Dorbolo, S.; Pakpour, M.; Lumay, G.

    2015-07-01

    We study the effect of freeze-thaw cycling on the packing fraction of equal spheres immersed in water. The water located between the grains experiences a dilatation during freezing and a contraction during melting. After several cycles, the packing fraction converges to a particular value η∞=0.595 independently of its initial value η0. This behavior is well reproduced by numerical simulations. Moreover, the numerical results allow one to analyze the packing structural configuration. With a Voronoï partition analysis, we show that the piles are fully random during the whole process and are characterized by two parameters: the average Voronoï volume μv (related to the packing fraction η ) and the standard deviation σv of Voronoï volumes. The freeze-thaw driving modify the volume standard deviation σv to converge to a particular disordered state with a packing fraction corresponding to the random loose packing fraction ηBRLP obtained by Bernal during his pioneering experimental work. Therefore, freeze-thaw cycling is found to be a soft and spatially homogeneous driving method for disordered granular materials.

  15. Spectral action models of gravity on packed swiss cheese cosmology

    NASA Astrophysics Data System (ADS)

    Ball, Adam; Marcolli, Matilde

    2016-06-01

    We present a model of (modified) gravity on spacetimes with fractal structure based on packing of spheres, which are (Euclidean) variants of the packed swiss cheese cosmology models. As the action functional for gravity we consider the spectral action of noncommutative geometry, and we compute its expansion on a space obtained as an Apollonian packing of three-dimensional spheres inside a four-dimensional ball. Using information from the zeta function of the Dirac operator of the spectral triple, we compute the leading terms in the asymptotic expansion of the spectral action. They consist of a zeta regularization of the divergent sum of the leading terms of the spectral actions of the individual spheres in the packing. This accounts for the contribution of points 1 and 3 in the dimension spectrum (as in the case of a 3-sphere). There is an additional term coming from the residue at the additional point in the real dimension spectrum that corresponds to the packing constant, as well as a series of fluctuations coming from log-periodic oscillations, created by the points of the dimension spectrum that are off the real line. These terms detect the fractality of the residue set of the sphere packing. We show that the presence of fractality influences the shape of the slow-roll potential for inflation, obtained from the spectral action. We also discuss the effect of truncating the fractal structure at a certain scale related to the energy scale in the spectral action.

  16. Non-universal Voronoi cell shapes in amorphous ellipsoid packs

    NASA Astrophysics Data System (ADS)

    Schaller, Fabian M.; Kapfer, Sebastian C.; Hilton, James E.; Cleary, Paul W.; Mecke, Klaus; De Michele, Cristiano; Schilling, Tanja; Saadatfar, Mohammad; Schröter, Matthias; Delaney, Gary W.; Schröder-Turk, Gerd E.

    2015-07-01

    In particulate systems with short-range interactions, such as granular matter or simple fluids, local structure determines the macroscopic physical properties. We analyse local structure metrics derived from the Voronoi diagram of oblate ellipsoids, for various aspect ratios α and global packing fractions φ\\text{g} . We focus on jammed static configurations of frictional ellipsoids, obtained by tomographic imaging and by discrete element method simulations. The rescaled distribution of local packing fractions φ\\text{l} , defined as the ratio of particle volume and its Voronoi cell volume, is found to be independent of the particle aspect ratio, and coincide with results for sphere packs. By contrast, the typical Voronoi cell shape, quantified by the Minkowski tensor anisotropy index β=β_02,0 , points towards a difference between random packings of spheres and those of oblate ellipsoids. While the average cell shape β of all cells with a given value of φ\\text{l} is similar in dense and loose jammed sphere packings, the structure of dense and loose ellipsoid packings differs substantially such that this does not hold true.

  17. Automating the packing heuristic design process with genetic programming.

    PubMed

    Burke, Edmund K; Hyde, Matthew R; Kendall, Graham; Woodward, John

    2012-01-01

    The literature shows that one-, two-, and three-dimensional bin packing and knapsack packing are difficult problems in operational research. Many techniques, including exact, heuristic, and metaheuristic approaches, have been investigated to solve these problems and it is often not clear which method to use when presented with a new instance. This paper presents an approach which is motivated by the goal of building computer systems which can design heuristic methods. The overall aim is to explore the possibilities for automating the heuristic design process. We present a genetic programming system to automatically generate a good quality heuristic for each instance. It is not necessary to change the methodology depending on the problem type (one-, two-, or three-dimensional knapsack and bin packing problems), and it therefore has a level of generality unmatched by other systems in the literature. We carry out an extensive suite of experiments and compare with the best human designed heuristics in the literature. Note that our heuristic design methodology uses the same parameters for all the experiments. The contribution of this paper is to present a more general packing methodology than those currently available, and to show that, by using this methodology, it is possible for a computer system to design heuristics which are competitive with the human designed heuristics from the literature. This represents the first packing algorithm in the literature able to claim human competitive results in such a wide variety of packing domains. PMID:21609273

  18. Pneumocytes Assemble Lung Surfactant as Highly Packed/Dehydrated States with Optimal Surface Activity.

    PubMed

    Cerrada, Alejandro; Haller, Thomas; Cruz, Antonio; Pérez-Gil, Jesús

    2015-12-01

    Pulmonary surfactant (PS) is an essential complex of lipids and specific proteins synthesized in alveolar type II pneumocytes, where it is assembled and stored intracellularly as multilayered organelles known as lamellar bodies (LBs). Once secreted upon physiological stimulation, LBs maintain a densely packed structure in the form of lamellar body-like particles (LBPs), which are efficiently transferred into the alveolar air-water interface, lowering surface tension to avoid lung collapse at end-expiration. In this work, the structural organization of membranes in LBs and LBPs freshly secreted by primary cultures of rat ATII cells has been compared with that of native lung surfactant membranes isolated from porcine bronchoalveolar lavage. PS assembles in LBs as crystalline-like highly ordered structures, with a highly packed and dehydrated state, which is maintained at supraphysiological temperatures. This relatively ordered/packed state is retained in secreted LBPs. The micro- and nanostructural examination of LBPs suggests the existence of high levels of structural complexity in comparison with the material purified from lavages, which may contain partially inactivated or spent structures. Additionally, freshly secreted surfactant LBPs exhibit superior activity when generating interfacial films and a higher intrinsic resistance to inactivating agents, such as serum proteins or meconium. We propose that LBs are assembled as an energy-activated structure competent to form very efficient interfacial films, and that the organization of lipids and proteins and the properties displayed by the films formed by LBPs are likely similar to those established at the alveolar interface and represent the actual functional structure of surfactant as it sustains respiration. PMID:26636941

  19. Effect of Crystal Packing on the Excitonic Properties of Rubrene Polymorphs

    NASA Astrophysics Data System (ADS)

    Wang, Xiaopeng; Garcia, Taylor; Monaco, Stephen; Schatschneider, Bohdan; Marom, Noa

    Singlet fission, the down-conversion of one singlet exciton into two triplet excitons, has been recently observed in molecular crystals of rubrene. The orthorhombic form of rubrene is the most stable in ambient conditions. However, rubrene has two additional known polymorphs, a triclinic form and a monoclinic form. To investigate the relative stability of the three polymorphs under different temperature and pressure conditions we use dispersion-inclusive density functional theory (DFT) with the pairwise Tkatchenko-Scheffler (TS) method and the many-body dispersion (MBD) method. Many-body perturbation theory is then employed to study the effect of crystal structure on the electronic and excitonic properties. Band structures are calculated within the GW approximation, where G is the one-particle Green's function and W is the screened Coulomb interaction, and optical properties are calculated by solving the Bethe-Salpeter equation (BSE). We find that crystal packing affects the band gaps, band dispersion, optical gaps, singlet-triplet gaps, and exciton localization in the three polymorphs of rubrene. Singlet fission efficiency may thus be improved by modulating the crystal packing.

  20. Body Piercing

    PubMed Central

    Koenig, Laura M; Carnes, Molly

    1999-01-01

    OBJECTIVE To review the current information on medical complications, psychological implications, and legislative issues related to body piercing, a largely unregulated industry in the United States. METHODS We conducted a MEDLINE search of English language articles from 1966 until May 1998 using the search terms “body piercing” and “ear piercing.” Bibliographies of these references were reviewed for additional citations. We also conducted an Internet search for “body piercing” on the World Wide Web. MAIN RESULTS: In this manuscript, we review the available body piercing literature. We conclude that body piercing is an increasingly common practice in the United States, that this practice carries substantial risk of morbidity, and that most body piercing in the United States is being performed by unlicensed, unregulated individuals. Primary care physicians are seeing growing numbers of patients with body pierces. Practitioners must be able to recognize, treat, and counsel patients on body piercing complications and be alert to associated psychological conditions in patients who undergo body piercing. PMID:10354260

  1. Generation of Random Particle Packings for Discrete Element Models

    NASA Astrophysics Data System (ADS)

    Abe, S.; Weatherley, D.; Ayton, T.

    2012-04-01

    An important step in the setup process of Discrete Element Model (DEM) simulations is the generation of a suitable particle packing. There are quite a number of properties such a granular material specimen should ideally have, such as high coordination number, isotropy, the ability to fill arbitrary bounding volumes and the absence of locked-in stresses. An algorithm which is able to produce specimens fulfilling these requirements is the insertion based sphere packing algorithm originally proposed by Place and Mora, 2001 [2] and extended in this work. The algorithm works in two stages. First a number of "seed" spheres are inserted into the bounding volume. In the second stage the gaps between the "seed" spheres are filled by inserting new spheres in a way so they have D+1 (i.e. 3 in 2D, 4 in 3D) touching contacts with either other spheres or the boundaries of the enclosing volume. Here we present an implementation of the algorithm and a systematic statistical analysis of the generated sphere packings. The analysis of the particle radius distribution shows that they follow a power-law with an exponent ≈ D (i.e. ≈3 for a 3D packing and ≈2 for 2D). Although the algorithm intrinsically guarantees coordination numbers of at least 4 in 3D and 3 in 2D, the coordination numbers realized in the generated packings can be significantly higher, reaching beyond 50 if the range of particle radii is sufficiently large. Even for relatively small ranges of particle sizes (e.g. Rmin = 0.5Rmax) the maximum coordination number may exceed 10. The degree of isotropy of the generated sphere packing is also analysed in both 2D and 3D, by measuring the distribution of orientations of vectors joining the centres of adjacent particles. If the range of particle sizes is small, the packing algorithm yields moderate anisotropy approaching that expected for a face-centred cubic packing of equal-sized particles. However, once Rmin < 0.3Rmax a very high degree of isotropy is demonstrated in

  2. Impact of Waterpipe Tobacco Pack Health Warnings on Waterpipe Smoking Attitudes: A Qualitative Analysis among Regular Users in London

    PubMed Central

    Jawad, Mohammed; Bakir, Ali; Ali, Mohammed; Grant, Aimee

    2015-01-01

    Background. Despite the rise in prevalence of waterpipe tobacco smoking, it has received little legislative enforcement from governing bodies, especially in the area of health warning labels. Methods. Twenty regular waterpipe tobacco smokers from London took part in five focus groups discussing the impact of waterpipe tobacco pack health warnings on their attitudes towards waterpipe smoking. We presented them with existing and mock waterpipe tobacco products, designed to be compliant with current and future UK/EU legislation. Data were analysed using thematic analysis. Results. Participants felt packs were less attractive and health warnings were more impactful as health warnings increased in size and packaging became less branded. However, participants highlighted their lack of exposure to waterpipe tobacco pack health warnings due to the inherent nature of waterpipe smoking, that is, smoking in a café with the apparatus already prepacked by staff. Health warnings at the point of consumption had more reported impact than health warnings at the point of sale. Conclusions. Waterpipe tobacco pack health warnings are likely to be effective if compliant with existing laws and exposed to end-users. Legislations should be reviewed to extend health warning labels to waterpipe accessories, particularly the apparatus, and to waterpipe-serving premises. PMID:26273642

  3. Body Basics

    MedlinePlus

    ... more about how the body works, what basic human anatomy is, and what happens when parts of the body don't function properly. Blood Bones, Muscles, and Joints Brain and Nervous System Digestive System Endocrine System Eyes Female Reproductive System ...

  4. 49 CFR 173.137 - Class 8-Assignment of packing group.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... packing group. The packing group of a Class 8 material is indicated in Column 5 of the § 172.101 Table. When the § 172.101 Table provides more than one packing group for a Class 8 material, the packing group... of this subchapter). A material that is determined not to be corrosive in accordance with...

  5. 49 CFR 173.137 - Class 8-Assignment of packing group.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... packing group. The packing group of a Class 8 material is indicated in Column 5 of the § 172.101 Table. When the § 172.101 Table provides more than one packing group for a Class 8 material, the packing group... of this subchapter). A material that is determined not to be corrosive in accordance with...

  6. 49 CFR 173.137 - Class 8-Assignment of packing group.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... packing group. The packing group of a Class 8 material is indicated in Column 5 of the § 172.101 Table. When the § 172.101 Table provides more than one packing group for a Class 8 material, the packing group... of this subchapter). A material that is determined not to be corrosive in accordance with...

  7. 7 CFR 51.691 - Standard pack for oranges except Temple variety.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 2 2014-01-01 2014-01-01 false Standard pack for oranges except Temple variety. 51... Grades of Oranges (Texas and States Other Than Florida, California, and Arizona) Standard Pack § 51.691 Standard pack for oranges except Temple variety. (a) Fruit shall be fairly uniform in size. When packed...

  8. 7 CFR 51.691 - Standard pack for oranges except Temple variety.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 2 2013-01-01 2013-01-01 false Standard pack for oranges except Temple variety. 51... Grades of Oranges (Texas and States Other Than Florida, California, and Arizona) Standard Pack § 51.691 Standard pack for oranges except Temple variety. (a) Fruit shall be fairly uniform in size. When packed...

  9. Thermodynamics and kinetics of pack aluminide coating formation on IN-100

    NASA Technical Reports Server (NTRS)

    Levine, S. R.; Caves, R. M.

    1973-01-01

    An investigation of the effects of pack variables on the formation of aluminide coatings on nickel-base superalloy IN-100 was conducted. Also, the thermodynamics and kinetics of coating formation were analyzed. Observed coating weights were in good agreement with predictions made from the analysis. Pack temperature rather than pack aluminum activity controls the principal coating phase formed. In 1 weight percent aluminum packs, aluminum weight gains were related to the halide pack activator. Solid-state nickel diffusion controlled coating formation from sodium fluoride and chloride and ammonium fluoride activated packs. In other ammonium and sodium halide activated 1 weight percent aluminum packs, gaseous diffusion controlled coating formation.

  10. A Geometric-Structure Theory for Maximally Random Jammed Packings

    NASA Astrophysics Data System (ADS)

    Tian, Jianxiang; Xu, Yaopengxiao; Jiao, Yang; Torquato, Salvatore

    2015-11-01

    Maximally random jammed (MRJ) particle packings can be viewed as prototypical glasses in that they are maximally disordered while simultaneously being mechanically rigid. The prediction of the MRJ packing density ϕMRJ, among other packing properties of frictionless particles, still poses many theoretical challenges, even for congruent spheres or disks. Using the geometric-structure approach, we derive for the first time a highly accurate formula for MRJ densities for a very wide class of two-dimensional frictionless packings, namely, binary convex superdisks, with shapes that continuously interpolate between circles and squares. By incorporating specific attributes of MRJ states and a novel organizing principle, our formula yields predictions of ϕMRJ that are in excellent agreement with corresponding computer-simulation estimates in almost the entire α-x plane with semi-axis ratio α and small-particle relative number concentration x. Importantly, in the monodisperse circle limit, the predicted ϕMRJ = 0.834 agrees very well with the very recently numerically discovered MRJ density of 0.827, which distinguishes it from high-density “random-close packing” polycrystalline states and hence provides a stringent test on the theory. Similarly, for non-circular monodisperse superdisks, we predict MRJ states with densities that are appreciably smaller than is conventionally thought to be achievable by standard packing protocols.

  11. A Geometric-Structure Theory for Maximally Random Jammed Packings

    PubMed Central

    Tian, Jianxiang; Xu, Yaopengxiao; Jiao, Yang; Torquato, Salvatore

    2015-01-01

    Maximally random jammed (MRJ) particle packings can be viewed as prototypical glasses in that they are maximally disordered while simultaneously being mechanically rigid. The prediction of the MRJ packing density ϕMRJ, among other packing properties of frictionless particles, still poses many theoretical challenges, even for congruent spheres or disks. Using the geometric-structure approach, we derive for the first time a highly accurate formula for MRJ densities for a very wide class of two-dimensional frictionless packings, namely, binary convex superdisks, with shapes that continuously interpolate between circles and squares. By incorporating specific attributes of MRJ states and a novel organizing principle, our formula yields predictions of ϕMRJ that are in excellent agreement with corresponding computer-simulation estimates in almost the entire α-x plane with semi-axis ratio α and small-particle relative number concentration x. Importantly, in the monodisperse circle limit, the predicted ϕMRJ = 0.834 agrees very well with the very recently numerically discovered MRJ density of 0.827, which distinguishes it from high-density “random-close packing” polycrystalline states and hence provides a stringent test on the theory. Similarly, for non-circular monodisperse superdisks, we predict MRJ states with densities that are appreciably smaller than is conventionally thought to be achievable by standard packing protocols. PMID:26568437

  12. Bernal's road to random packing and the structure of liquids

    NASA Astrophysics Data System (ADS)

    Finney, John L.

    2013-11-01

    Until the 1960s, liquids were generally regarded as either dense gases or disordered solids, and theoretical attempts at understanding their structures and properties were largely based on those concepts. Bernal, himself a crystallographer, was unhappy with either approach, preferring to regard simple liquids as 'homogeneous, coherent and essentially irregular assemblages of molecules containing no crystalline regions'. He set about realizing this conceptual model through a detailed examination of the structures and properties of random packings of spheres. In order to test the relevance of the model to real liquids, ways had to be found to realize and characterize random packings. This was at a time when computing was slow and in its infancy, so he and his collaborators set about building models in the laboratory, and examining aspects of their structures in order to characterize them in ways which would enable comparison with the properties of real liquids. Some of the imaginative - often time consuming and frustrating - routes followed are described, as well the comparisons made with the properties of simple liquids. With the increase of the power of computers in the 1960s, computational approaches became increasingly exploited in random packing studies. This enabled the use of packing concepts, and the tools developed to characterize them, in understanding systems as diverse as metallic glasses, crystal-liquid interfaces, protein structures, enzyme-substrate interactions and the distribution of galaxies, as well as their exploitation in, for example, oil extraction, understanding chromatographic separation columns, and packed beds in industrial processes.

  13. Pentagon packing models for "all-pentamer" virus structures.

    PubMed Central

    Tarnai, T; Gáspár, Z; Szalai, L

    1995-01-01

    A connection is made between 1) the observed structures of virus capsids whose capsomers are all pentamers and 2) the mathematical problem of determination of the largest size of a given number of equal regular spherical pentagons that can be packed on the surface of the unit sphere without overlapping. It is found that papillomaviruses provide the conjectured solution to the spherical pentagon packing problem for 72 pentagons. Thus, a study of some virus structures has given additional insight into a mathematical problem. At the same time this mathematical problem enables prediction of an octahedral form of papillomavirus particles consisting of 24 pentamers. It is also found that the various tubular and spherical "all-pentamer" virus structures identified so far can be represented by closet-packing arrangements of equal morphological units composed of equal regular pentagons on a cylinder and on a sphere. PMID:8527676

  14. Lightweight, Flexible, Thin, Integrated Solar-Power Packs

    NASA Technical Reports Server (NTRS)

    Hanson, Robert R.

    2004-01-01

    Lightweight, flexible, thin, one-piece, solar-power packs are undergoing development. Each power pack of this type is a complete, modular, integrated power-supply system comprising three power subsystems that, in conventional practice, have been constructed as separate units and connected to each other by wires. These power packs are amenable to a variety of uses: For example, they could be laminated to the tops of tents and other shelters to provide or augment power for portable electronic equipment in the field, and they could be used as power sources for such small portable electronic systems as radio transceivers (including data relays and cellular telephones), laptop computers, video camcorders, and Global Positioning System receivers.

  15. Photovoltaic dryer with dual packed beds for drying medical herb

    SciTech Connect

    Abdel-Rehim, Z.S.; Fahmy, F.H.

    1998-03-01

    This work presents design and optimization of a cylindrical photovoltaic dryer with dual packed beds thermal energy storage for drying medical herb. The dryer is provided with electrical heater where the electrical energy is generated by using photovoltaic system. The electrical heater is designed and sized to realize continuous drying (day and night) to minimize the drying time. Two packed beds are used to fix the drying temperature in dryer during day and night. The main packed bed thermal energy storage is charged during the sunlight hours directly, to realize continued drying after sunset. An efficient PV dryer is devised to work under forced air created by air blower and heated by the electrical coils.

  16. How much biomass do plant communities pack per unit volume?

    PubMed Central

    Rheault, Guillaume; Bonin, Laurianne; Roca, Irene Torrecilla; Martin, Charles A.; Desrochers, Louis; Seiferling, Ian

    2015-01-01

    Aboveground production in terrestrial plant communities is commonly expressed in amount of carbon, or biomass, per unit surface. Alternatively, expressing production per unit volume allows the comparison of communities by their fundamental capacities in packing carbon. In this work we reanalyzed published data from more than 900 plant communities across nine ecosystems to show that standing dry biomass per unit volume (biomass packing) consistently averages around 1 kg/m3 and rarely exceeds 5 kg/m3 across ecosystem types. Furthermore, we examined how empirical relationships between aboveground production and plant species richness are modified when standing biomass is expressed per unit volume rather than surface. We propose that biomass packing emphasizes species coexistence mechanisms and may be an indicator of resource use efficiency in plant communities. PMID:25802814

  17. Emergence of Gamma distributions in granular materials and packing models

    NASA Astrophysics Data System (ADS)

    Aste, T.; di Matteo, T.

    2008-02-01

    We study the distribution of volume fluctuations in experiments and numerical simulations concerning equal-sized sphere packings prepared with different techniques. We show that the distribution of the local volumes (Voronoï cells) and also the distributions of the global volumes (whole samples) follow remarkably well a shifted and rescaled Gamma distribution that we name a k-Gamma distribution. Such agreement is robust over a broad range of packing fractions and it is observed for several distinct systems. This distribution is characterized by the average packing fraction and a shape parameter “ k ” which is very sensitive to changes in the structural organization. A statistical mechanics approach predicts such k-Gamma distribution at statistical equilibrium and it links the parameter k with the number of elementary cells which are exchanging volume during the system preparation. The thermodynamical equivalent of k and its relation with the “granular temperature” are also discussed.

  18. FY-87 packing fabrication techniques (commercial waste form) results

    SciTech Connect

    Werry, E.V.; Gates, T.E.; Cabbage, K.S.; Eklund, J.D.

    1988-04-01

    This report covers the investigation of fabrication techniques associated with the development of suitable materials and methods to provide a prefabricated packing for waste packages for the Basalt Waste Isolation Project (BWIP). The principal functions of the packing are to minimize container corrosion during the 300 to 1000 years following repository closure and provide long-term control of the release of radionuclides from the waste package. The investigative work, discussed in this report, was specifically conceived to develop the design criteria for production of full-scale prototypical packing rings. The investigative work included the preparation of procedures, the preparation of fabrication materials, physical properties, and the determination of the engineering properties. The principal activities were the preparation of the materials and the determination of the physical properties. 21 refs., 20 figs., 14 tabs.

  19. Hydrogen gettering packing material, and process for making same

    DOEpatents

    LeMay, James D.; Thompson, Lisa M.; Smith, Henry Michael; Schicker, James R.

    2001-01-01

    A hydrogen gettering system for a sealed container is disclosed comprising packing material for use within the sealed container, and a coating film containing hydrogen gettering material on at least a portion of the surface of such packing material. The coating film containing the hydrogen gettering material comprises a mixture of one or more organic materials capable of reacting with hydrogen and one or more catalysts capable of catalyzing the reaction of hydrogen with such one or more organic materials. The mixture of one or more organic materials capable of reacting with hydrogen and the one or more catalysts is dispersed in a suitable carrier which preferably is a curable film-forming material. In a preferred embodiment, the packing material comprises a foam material which is compatible with the coating film containing hydrogen gettering material thereon.

  20. Patterned graphone—a novel template for molecular packing

    NASA Astrophysics Data System (ADS)

    Reddy, C. D.; Zhang, Y. W.; Shenoy, V. B.

    2012-04-01

    Precise positioning and packing of nanoscale building blocks is essential for the fabrication of many nanoelectro-mechanical devices. Carrying out such manipulations at the nanoscale still remains a challenge. Here we propose the use of graphone domain arrays embedded in a graphene sheet as a template to precisely position and pack molecules. Our atomistic simulations show that a graphone domain is able to adopt well-defined three-dimensional geometries, which in turn create ‘energy wells’ to trap molecules by means of physisorption. Using the C60 molecule as a model block, the stable trapping conditions are identified. The present work presents a novel route to position and pack molecules for nanoengineering applications.

  1. Body lice

    MedlinePlus

    ... off the body. Your provider may prescribe a skin cream or a wash that contains permethrin, malathione, or benzyl alcohol. If your case is severe, the provider may prescribe medicine that you take by mouth.

  2. Body Image

    MedlinePlus

    ... spider veins Body dysmorphic disorder (BDD) Eating disorders Anorexia nervosa Binge eating disorder Bulimia nervosa Over-exercising ... conditions? Visit our Mental health section. Fact sheets Anorexia nervosa Binge eating disorder Bulimia nervosa Cosmetics and ...

  3. Body Signals.

    ERIC Educational Resources Information Center

    Gurley-Dilger, 'Laine

    1986-01-01

    Describes an activity in which students observe pairs of students engaged in conversation. Observations of "body language" are made, shifts in stance, and duration of stance. Discusses the application of this type of study to other species. (TW)

  4. Body lice

    MedlinePlus

    ... also get lice from infected clothing, towels, or bedding. Body lice are bigger than other types of ... last if you: Bathe regularly Wash clothes and bedding at least once a week Placing clothes in ...

  5. A Quantitative Study on Packing Density and Pozzolanic Activity of Cementitious Materials Based on the Compaction Packing Model

    NASA Astrophysics Data System (ADS)

    Gong, Jianqing; Chou, Kai; Huang, Zheng Yu; Zhao, Minghua

    2014-08-01

    A brief introduction to the theoretical basis of compaction packing model (CPM) and an over-view of the principle of the specific strength method provided the starting point of this study. Then, research on quantitative relations was carried out to find the correlation between the contribution rate of the pozzolanic activity and the contribution value of packing density when CPM was applied to fine powder mixture systems. The concept of the contribution value of the packing density being in direct correspondence with the contribution rate was proved by the compressive strength results and SEM images. The results indicated that the variation rule of the contribution rate of the pozzolanic activity is similar to that of the contribution value of packing density as calculated by CPM. This means the contribution value of the packing density could approximately simulate the change tendency of the contribution rate of the pozzolanic activity, which is of significant value for the future of mix designs for high and ultra-high performance concrete.

  6. Characterization of maximally random jammed sphere packings: Voronoi correlation functions.

    PubMed

    Klatt, Michael A; Torquato, Salvatore

    2014-11-01

    We characterize the structure of maximally random jammed (MRJ) sphere packings by computing the Minkowski functionals (volume, surface area, and integrated mean curvature) of their associated Voronoi cells. The probability distribution functions of these functionals of Voronoi cells in MRJ sphere packings are qualitatively similar to those of an equilibrium hard-sphere liquid and partly even to the uncorrelated Poisson point process, implying that such local statistics are relatively structurally insensitive. This is not surprising because the Minkowski functionals of a single Voronoi cell incorporate only local information and are insensitive to global structural information. To improve upon this, we introduce descriptors that incorporate nonlocal information via the correlation functions of the Minkowski functionals of two cells at a given distance as well as certain cell-cell probability density functions. We evaluate these higher-order functions for our MRJ packings as well as equilibrium hard spheres and the Poisson point process. It is shown that these Minkowski correlation and density functions contain visibly more information than the corresponding standard pair-correlation functions. We find strong anticorrelations in the Voronoi volumes for the hyperuniform MRJ packings, consistent with previous findings for other pair correlations [A. Donev et al., Phys. Rev. Lett. 95, 090604 (2005)PRLTAO0031-900710.1103/PhysRevLett.95.090604], indicating that large-scale volume fluctuations are suppressed by accompanying large Voronoi cells with small cells, and vice versa. In contrast to the aforementioned local Voronoi statistics, the correlation functions of the Voronoi cells qualitatively distinguish the structure of MRJ sphere packings (prototypical glasses) from that of not only the Poisson point process but also the correlated equilibrium hard-sphere liquids. Moreover, while we did not find any perfect icosahedra (the locally densest possible structure in which a

  7. [Removal of Mixed Waste Gases by a Biotrickling Filter Packed with a Novel Combined Packing Material].

    PubMed

    Mei, Yu; Cheng, Zhuo-wei; Wang, Jia-de; Lu, Yin

    2015-12-01

    A pilot biotrickling filter (BTF) was set up for removal of a mixed waste gas containing toluene and ethanol. The packing material was composed of polyhedral sphere and polyhedral hollow column previously designed by our group. The results showed this BTF could successfully start up within only 8 d and the average eliminate capacities for toluene and ethanol were 97.14 and 113.10 g · (m³ · h)⁻¹, respectively. Empty bed residence time (EBRT) and the inlet concentration had effects on the removal of toluene. The maximum elimination capacity of toluene and ethanol was 123.34 and 206.36 g (m³ · h)⁻¹ under EBRT of 21.11 s, respectively. However, the effect of spray liquid density was not obvious, and the optimal value of solution and gas ratio was 6.82 L · m⁻³. The influence of unstable processing condition on its performance was also investigated. NaOH solution could effectively reduce the plugging of the filler layer, and the removal capability of pollutant could be recovered within 3 days. After the running was stopped for 10 d, the removal performance of this BTF could be quickly recovered. PMID:27011972

  8. Bog bodies.

    PubMed

    Lynnerup, Niels

    2015-06-01

    In northern Europe during the Iron Age, many corpses were deposited in bogs. The cold, wet and anaerobic environment leads in many cases to the preservation of soft tissues, so that the bodies, when found and excavated several thousand years later, are remarkably intact. Since the 19th century the bog bodies have been studied using medical and natural scientific methods, and recently many bog bodies have been re-examined using especially modern, medical imaging techniques. Because of the preservation of soft tissue, especially the skin, it has been possible to determine lesions and trauma. Conversely, the preservation of bones is less good, as the mineral component has been leached out by the acidic bog. Together with water-logging of collagenous tissue, this means that if the bog body is simply left to dry out when found, as was the case pre-19th century, the bones may literally warp and shrink, leading to potential pitfalls in paleopathological diagnostics. Bog bodies have in several instances been crucial in determining the last meal, as gut contents may be preserved, and thus augment our knowledge on pre-historic diet by adding to, for example, stable isotope analyses. This article presents an overview of our knowledge about the taphomic processes as well as the methods used in bog body research. PMID:25998635

  9. Close-packed-array (CPA) thermoelectric module development status

    NASA Astrophysics Data System (ADS)

    Brittain, Wayne M.

    The technical approach for modifying the current two-watt radioisotope thermoelectric generator (RTG) thermoelectric module to expand its applicability to more severe terrestrial applications and planetary space missions is to increase the operating temperature capability of the current design as well as reconfigure the minicouple array into a more densely packed CPA arrangement with the objective of increasing the module dynamic loading capability while minimizing size and weight. Use of the CPA technology will result in approximately a factor of five reduction in the area of the thermoelectric module cross section from the current minicouple packing density exemplified by the two-watt module.

  10. Effect of packing density on strain estimation by Fry method

    NASA Astrophysics Data System (ADS)

    Srivastava, Deepak; Ojha, Arun

    2015-04-01

    Fry method is a graphical technique that uses relative movement of material points, typically the grain centres or centroids, and yields the finite strain ellipse as the central vacancy of a point distribution. Application of the Fry method assumes an anticlustered and isotropic grain centre distribution in undistorted samples. This assumption is, however, difficult to test in practice. As an alternative, the sedimentological degree of sorting is routinely used as an approximation for the degree of clustering and anisotropy. The effect of the sorting on the Fry method has already been explored by earlier workers. This study tests the effect of the tightness of packing, the packing density%, which equals to the ratio% of the area occupied by all the grains and the total area of the sample. A practical advantage of using the degree of sorting or the packing density% is that these parameters, unlike the degree of clustering or anisotropy, do not vary during a constant volume homogeneous distortion. Using the computer graphics simulations and the programming, we approach the issue of packing density in four steps; (i) generation of several sets of random point distributions such that each set has same degree of sorting but differs from the other sets with respect to the packing density%, (ii) two-dimensional homogeneous distortion of each point set by various known strain ratios and orientation, (iii) estimation of strain in each distorted point set by the Fry method, and, (iv) error estimation by comparing the known strain and those given by the Fry method. Both the absolute errors and the relative root mean squared errors give consistent results. For a given degree of sorting, the Fry method gives better results in the samples having greater than 30% packing density. This is because the grain centre distributions show stronger clustering and a greater degree of anisotropy with the decrease in the packing density. As compared to the degree of sorting alone, a

  11. Antarctic pack ice: boundaries established from nimbus I pictures.

    PubMed

    Predoehl, M C

    1966-08-19

    Television and photofacsimile constructed infrared pictures taken by the Nimbus I meteorological satellite between 28 August and 22 September 1964 were analyzed for indications of the pack-ice boundary around Antarctica. Mean ice boundaries were established around the entire continent from both TV and infrared pictures, from which were estimated pack-ice areas of 19.81 by 10(6) and16.78 by 10(6) square kilometers, respectively; the difference is attributed to difference in subjective discernment of a boundary. PMID:17780643

  12. Cut endotracheal tube for endoscopic removal of an ingested push-through pack

    PubMed Central

    Tateno, Yuki; Suzuki, Ryoji

    2016-01-01

    A 52-year-old female presented to our clinic after accidentally ingesting a push-through pack (PTP). After determining that the PTP was present in the stomach, we successfully and safely removed it endoscopically by using a handmade endoscopic hood fashioned from a cut endotracheal tube. Foreign body ingestion is a common clinical problem, and most ingested foreign bodies pass spontaneously. However, the ingestion of sharp objects, such as PTPs, increases the risk of complications, and urgent endoscopy is recommended to remove such objects. Previous studies have reported the use of other devices, both commercial and handmade, for the safe endoscopic removal of foreign bodies. The novel design of our handmade hood for the removal of the PTP, which was fashioned from a cut endotracheal tube, was beneficial in terms of maintaining a wide visual field, patient safety and tolerance, and easy preparation compared to previously reported commercial and handmade devices. It may be a viable and safe device for the retrieval of PTPs and other sharp foreign bodies. PMID:27433294

  13. Endoscopic retrieval of baggies in body stuffers

    PubMed Central

    Shabani, Mahtab; Zamani, Nasim; Hassanian-Moghaddam, Hossein

    2016-01-01

    Background and study aims: Body packing/stuffing is currently a huge medical problem. A conservative approach and waiting for spontaneous packet expulsion are usually recommended. However, in a patient with packets stuck in the stomach, surgical treatments are generally advocated if complications occur. Endoscopic evacuation of the packets is generally not favored because of its potential hazards, including manipulation and rupture of the packets and deterioration of the patients' condition. However, it may prevent more invasive treatment modalities including surgical intervention. We present case reports on four symptomatic body stuffers with potentially dangerous ingestions who underwent endoscopic evacuation of their packets and survived. PMID:27092325

  14. PlanetPack: A radial-velocity time-series analysis tool facilitating exoplanets detection, characterization, and dynamical simulations

    NASA Astrophysics Data System (ADS)

    Baluev, Roman V.

    2013-08-01

    We present PlanetPack, a new software tool that we developed to facilitate and standardize the advanced analysis of radial velocity (RV) data for the goal of exoplanets detection, characterization, and basic dynamical N-body simulations. PlanetPack is a command-line interpreter, that can run either in an interactive mode or in a batch mode of automatic script interpretation. Its major abilities include: (i) advanced RV curve fitting with the proper maximum-likelihood treatment of unknown RV jitter; (ii) user-friendly multi-Keplerian as well as Newtonian N-body RV fits; (iii) use of more efficient maximum-likelihood periodograms that involve the full multi-planet fitting (sometimes called as “residual” or “recursive” periodograms); (iv) easily calculatable parametric 2D likelihood function level contours, reflecting the asymptotic confidence regions; (v) fitting under some useful functional constraints is user-friendly; (vi) basic tasks of short- and long-term planetary dynamical simulation using a fast Everhart-type integrator based on Gauss-Legendre spacings; (vii) fitting the data with red noise (auto-correlated errors); (viii) various analytical and numerical methods for the tasks of determining the statistical significance. It is planned that further functionality may be added to PlanetPack in the future. During the development of this software, a lot of effort was made to improve the calculational speed, especially for CPU-demanding tasks. PlanetPack was written in pure C++ (standard of 1998/2003), and is expected to be compilable and useable on a wide range of platforms.

  15. Involvement of Clostridium gasigenes and C. algidicarnis in 'blown pack' spoilage of Brazilian vacuum-packed beef.

    PubMed

    Silva, Alessandra R; Paulo, Ezio N; Sant'Ana, Anderson S; Chaves, Rafael D; Massaguer, Pilar R

    2011-08-15

    The objectives of this study were to isolate psychrotrophic clostridia from Brazilian vacuum-packed beef cuts (spoiled or not) and to identify the isolates by using 16S rRNA gene sequencing. Anaerobic psychrotrophic microorganisms were also enumerated and samples were collected to verify the incidence of psychrotrophic clostridia in the abattoir environment. Vacuum-packed beef cuts (n=8 grossly distended and n=5 non-spoiled) and environmental samples were obtained from a beef packing plant located in the state of São Paulo, Brazil. Each sample was divided in three subsamples (exudate, beef surface and beef core) that were analyzed for vegetative forms, total spore-forming, and sulfide reducing spore-forming, both activated by alcohol and heat. Biochemical profiles of the isolates were obtained using API20A, with further identification using 16S rRNA gene sequencing. The growth temperature and the pH range were also assessed. Populations of psychrotrophic anaerobic vegetative microorganisms of up to 10(10)CFU/(g, mL or 100 cm(2)) were found in 'blown pack' samples, while in non-spoiled samples populations of 10(5)CFU/(g, CFU/mL or CFU/100 cm(2)) was found. Overall, a higher population of total spores and sulfide reducing spores activated by heat in spoiled samples was found. Clostridium gasigenes (n=10) and C. algidicarnis (n=2) were identified using 16S rRNA gene sequencing. Among the ten C. gasigenes isolates, six were from spoiled samples (C1, C2 and C9), two were isolated from non-spoiled samples (C4 and C5) and two were isolated from the hide and the abattoir corridor/beef cut conveyor belt. C. algidicarnis was recovered from spoiled beef packs (C2). Although some samples (C3, C7, C10 and C14) presented signs of 'blown pack' spoilage, Clostridium was not recovered. C. algidicarnis (n=1) and C. gasigenes (n=9) isolates have shown a psychrotrophic behavior, grew in the range 6.2-8.2. This is the first report on the isolation of psychrotrophic Clostridium (C

  16. Comparison of the biological NH3 removal characteristics among four inorganic packing materials.

    PubMed

    Hirai, M; Kamamoto, M; Yani, M; Shoda, M

    2001-01-01

    Four inorganic packing materials were evaluated in terms of their availability as a packing material of a packed tower deodorization apparatus (biofilter) from the viewpoints of biological NH3 removal characteristics and some physical properties. Porous ceramics (A), calcinated cristobalite (B), calcinated and formed obsidian (C), granulated and calculated soil (D) were used. The superiority of these packing materials determined based on the values of non-biological removal per unit weight or unit volume of packing material, complete removal capacity of NH3 per unit weight of packing material per day or unit volume of packing material per day and pressure drop of the packed bed was in the order of A approximately = C > B > or = D. Packing materials A and C with high porosity, maximum water content, and suitable mean pore diameter showed excellent removal capacity. PMID:16233018

  17. Impact of conduit geometry on the performance of typical particulate microchip packings.

    PubMed

    Jung, Stephanie; Höltzel, Alexandra; Ehlert, Steffen; Mora, Jose-Angel; Kraiczek, Karsten; Dittmann, Monika; Rozing, Gerard P; Tallarek, Ulrich

    2009-12-15

    This work investigates the impact of conduit geometry on the chromatographic performance of typical particulate microchip packings. For this purpose, high-performance liquid chromatography (HPLC)/UV-microchips with separation channels of quadratic, trapezoidal, or Gaussian cross section were fabricated by direct laser ablation and lamination of multiple polyimide layers and then slurry-packed with either 3 or 5 microm spherical porous C8-silica particles under optimized packing conditions. Experimentally determined plate height curves for the empty microchannels are compared with dispersion coefficients from theoretical calculations. Packing densities and plate height curves for the various microchip packings are presented and conclusively explained. The 3 microm packings display a high packing density irrespective of their conduit geometries, and their performance reflects the dispersion behavior of the empty channels. Dispersion in 5 microm packings correlates with the achieved packing densities, which are limited by the number and accessibility of corners in a given conduit shape. PMID:19916548

  18. A Comparison of Skin Interface Temperature Response Between the ProHeat™ Instant Reusable Hot Pack and the Standard Hydrocollator Steam Pack

    PubMed Central

    Tomaszewski, Donald; Dandorph, Michael J.; Manning, James

    1992-01-01

    The ProHeat™ reusable hot pack is being used increasingly as a substitute for the standard hydrocollator steam pack. This study evaluated the effects of these two modalities on skin temperature. Seventeen subjects were studied during separate 30-minute applications of a ProHeat pack with a wet barrier, a ProHeat pack with a dry barrier, a hydrocollator pack, and a control pack on their nondominant calf. We measured the skin interface temperature and pack surface temperature during each application with surface thermocouples. The skin interface temperature rise time to the minimum therapeutic temperature (104°F) and the total time at and above the minimum therapeutic temperature, for each application, were analyzed using an analysis of variance (ANOVA) with repeated measures (p<.05). The ProHeat pack application, with one layer of wet toweling as a barrier, was not significantly different from the hydrocollator steam pack application. We conclude that the ProHeat pack, prepared with a wet barrier, can be considered a viable alternative to the standard hydrocollator steam pack. PMID:16558193

  19. Body Imaging

    NASA Technical Reports Server (NTRS)

    2001-01-01

    The high-tech art of digital signal processing (DSP) was pioneered at NASA's Jet Propulsion Laboratory (JPL) in the mid-1960s for use in the Apollo Lunar Landing Program. Designed to computer enhance pictures of the Moon, this technology became the basis for the Landsat Earth resources satellites and subsequently has been incorporated into a broad range of Earthbound medical and diagnostic tools. DSP is employed in advanced body imaging techniques including Computer-Aided Tomography, also known as CT and CATScan, and Magnetic Resonance Imaging (MRI). CT images are collected by irradiating a thin slice of the body with a fan-shaped x-ray beam from a number of directions around the body's perimeter. A tomographic (slice-like) picture is reconstructed from these multiple views by a computer. MRI employs a magnetic field and radio waves, rather than x-rays, to create images. In this photograph, a patient undergoes an open MRI.

  20. Body Imaging

    NASA Technical Reports Server (NTRS)

    2001-01-01

    The high-tech art of digital signal processing (DSP) was pioneered at NASA's Jet Propulsion Laboratory (JPL) in the mid-1960s for use in the Apollo Lunar Landing Program. Designed to computer enhance pictures of the Moon, this technology became the basis for the Landsat Earth resources satellites and subsequently has been incorporated into a broad range of Earthbound medical and diagnostic tools. DSP is employed in advanced body imaging techniques including Computer-Aided Tomography, also known as CT and CATScan, and Magnetic Resonance Imaging (MRI). CT images are collected by irradiating a thin slice of the body with a fan-shaped x-ray beam from a number of directions around the body's perimeter. A tomographic (slice-like) picture is reconstructed from these multiple views by a computer. MRI employs a magnetic field and radio waves, rather than x-rays, to create images.

  1. Disk Density Tuning of a Maximal Random Packing

    PubMed Central

    Ebeida, Mohamed S.; Rushdi, Ahmad A.; Awad, Muhammad A.; Mahmoud, Ahmed H.; Yan, Dong-Ming; English, Shawn A.; Owens, John D.; Bajaj, Chandrajit L.; Mitchell, Scott A.

    2016-01-01

    We introduce an algorithmic framework for tuning the spatial density of disks in a maximal random packing, without changing the sizing function or radii of disks. Starting from any maximal random packing such as a Maximal Poisson-disk Sampling (MPS), we iteratively relocate, inject (add), or eject (remove) disks, using a set of three successively more-aggressive local operations. We may achieve a user-defined density, either more dense or more sparse, almost up to the theoretical structured limits. The tuned samples are conflict-free, retain coverage maximality, and, except in the extremes, retain the blue noise randomness properties of the input. We change the density of the packing one disk at a time, maintaining the minimum disk separation distance and the maximum domain coverage distance required of any maximal packing. These properties are local, and we can handle spatially-varying sizing functions. Using fewer points to satisfy a sizing function improves the efficiency of some applications. We apply the framework to improve the quality of meshes, removing non-obtuse angles; and to more accurately model fiber reinforced polymers for elastic and failure simulations. PMID:27563162

  2. 49. TILE PACKING AREA AND APPRENTICE WORKSPACE, SECOND FLOOR, SOUTH ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    49. TILE PACKING AREA AND APPRENTICE WORKSPACE, SECOND FLOOR, SOUTH END OF EAST WING. THE SKYLIGHT, ADDED IN 1976. COVERS A ROOF OPENING LEFT FOR THE CHIMNEY OF A POSSIBLE THIRD BISCUIT KILN. - Moravian Pottery & Tile Works, Southwest side of State Route 313 (Swamp Road), Northwest of East Court Street, Doylestown, Bucks County, PA

  3. A Gilbert-Varshamov type bound for Euclidean packings

    NASA Astrophysics Data System (ADS)

    Nebe, Gabriele; Xing, Chaoping

    2008-12-01

    This paper develops a method to obtain a Gilbert-Varshamov type bound for dense packings in the Euclidean spaces using suitable lattices. For the Leech lattice the obtained bounds are quite reasonable for large dimensions, better than the Minkowski-Hlawka bound, but not as good as the lower bound given by Keith Ball in 1992.

  4. Optimizing packing fraction in granular media composed of overlapping spheres.

    PubMed

    Roth, Leah K; Jaeger, Heinrich M

    2016-01-28

    What particle shape will generate the highest packing fraction when randomly poured into a container? In order to explore and navigate the enormous search space efficiently, we pair molecular dynamics simulations with artificial evolution. Arbitrary particle shape is represented by a set of overlapping spheres of varying diameter, enabling us to approximate smooth surfaces with a resolution proportional to the number of spheres included. We discover a family of planar triangular particles, whose packing fraction of ϕ ∼ 0.73 is among the highest experimental results for disordered packings of frictionless particles. We investigate how ϕ depends on the arrangement of spheres comprising an individual particle and on the smoothness of the surface. We validate the simulations with experiments using 3D-printed copies of the simplest member of the family, a planar particle consisting of three overlapping spheres with identical radius. Direct experimental comparison with 3D-printed aspherical ellipsoids demonstrates that the triangular particles pack exceedingly well not only in the limit of large system size but also when confined to small containers. PMID:26592541

  5. Flat pack interconnection structure simplifies modular electronic assemblies

    NASA Technical Reports Server (NTRS)

    Katzin, L.

    1967-01-01

    Flat pack interconnection structure composed of stick modules simplifies modular electronic assemblies by allowing a single axis mother board. Two of the wiring planes are located in the stick module, which is the lower level of assembly, with the third wiring plane in the mother board.

  6. 21 CFR 890.5710 - Hot or cold disposable pack.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Hot or cold disposable pack. 890.5710 Section 890.5710 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Therapeutic Devices § 890.5710 Hot or...

  7. 21 CFR 890.5710 - Hot or cold disposable pack.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Hot or cold disposable pack. 890.5710 Section 890.5710 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Therapeutic Devices § 890.5710 Hot or...

  8. 21 CFR 890.5710 - Hot or cold disposable pack.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Hot or cold disposable pack. 890.5710 Section 890.5710 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Therapeutic Devices § 890.5710 Hot or...

  9. 21 CFR 890.5710 - Hot or cold disposable pack.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Hot or cold disposable pack. 890.5710 Section 890.5710 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Therapeutic Devices § 890.5710 Hot or...

  10. Packed bed heat storage: Continuum mechanics model and validation

    NASA Astrophysics Data System (ADS)

    Knödler, Philipp; Dreißigacker, Volker; Zunft, Stefan

    2016-05-01

    Thermal energy storage (TES) systems are key elements for various types of new power plant concepts. As possible cost-effective storage inventory option, packed beds of miscellaneous material come into consideration. However, high technical risks arise due to thermal expansion and shrinking of the packed bed's particles during cyclic thermal operation, possibly leading to material failure. Therefore, suitable tools for designing the heat storage system are mandatory. While particle discrete models offer detailed simulation results, the computing time for large scale applications is inefficient. In contrast, continuous models offer time-efficient simulation results but are in need of effective packed bed parameters. This work focuses on providing insight into some basic methods and tools on how to obtain such parameters and on how they are implemented into a continuum model. In this context, a particle discrete model as well as a test rig for carrying out uniaxial compression tests (UCT) is introduced. Performing of experimental validation tests indicate good agreement with simulated UCT results. In this process, effective parameters required for a continuous packed bed model were identified and used for continuum simulation. This approach is validated by comparing the simulated results with experimental data from another test rig. The presented method significantly simplifies subsequent design studies.

  11. Recess Physical Activity Packs in Elementary Schools: A Qualitative Investigation

    ERIC Educational Resources Information Center

    Elliott, Steven; Combs, Sue; Boyce, Robert

    2011-01-01

    To supplement the present weekly allotment of 30 minutes of physical education, a school district in southeastern North Carolina identified recess time as part of the state mandated (HSP-S-000) 150 minutes of physical activity (PA) per week and have purchased fitness equipment (recess packs) for the children to use. Twelve participants were…

  12. Learning To Change. A WEA Equal Opportunities Training Pack.

    ERIC Educational Resources Information Center

    Workers Educational Association, London (England).

    This training pack contains materials to help embed the principles of equal opportunities into the practice of part-time tutors and voluntary members of the Workers' Educational Association (WEA), a national voluntary organization dedicated to giving adults in the United Kingdom access to organized learning. Part 1 describes the rationale for the…

  13. Supramolecular Packing Controls H2 Photocatalysis in Chromophore Amphiphile Hydrogels

    PubMed Central

    2015-01-01

    Light harvesting supramolecular assemblies are potentially useful structures as components of solar-to-fuel conversion materials. The development of these functional constructs requires an understanding of optimal packing modes for chromophores. We investigated here assembly in water and the photocatalytic function of perylene monoimide chromophore amphiphiles with different alkyl linker lengths separating their hydrophobic core and the hydrophilic carboxylate headgroup. We found that these chromophore amphiphiles (CAs) self-assemble into charged nanostructures of increasing aspect ratio as the linker length is increased. The addition of salt to screen the charged nanostructures induced the formation of hydrogels and led to internal crystallization within some of the nanostructures. For linker lengths up to seven methylenes, the CAs were found to pack into 2D crystalline unit cells within ribbon-shaped nanostructures, whereas the nine methylene CAs assembled into long nanofibers without crystalline molecular packing. At the same time, the different molecular packing arrangements after charge screening led to different absorbance spectra, despite the identical electronic properties of all PMI amphiphiles. While the crystalline CAs formed electronically coupled H-aggregates, only CAs with intermediate linker lengths showed evidence of high intermolecular orbital overlap. Photocatalytic hydrogen production using a nickel-based catalyst was observed in all hydrogels, with the highest turnovers observed for CA gels having intermediate linker lengths. We conclude that the improved photocatalytic performance of the hydrogels formed by supramolecular assemblies of the intermediate linker CA molecules likely arises from improved exciton splitting efficiencies due to their higher orbital overlap. PMID:26593389

  14. Characteristics and Nitrogen Value of Stratified Bedded Pack Dairy Manure

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Compost-bedded-pack (CBP) dairy barns are relatively new, but CBP manure has not been characterized in detail and there are no published data on its N supply. We measured physical characteristics, nutrient concentration, N mineralization, and N supply to corn (Zea mays L.) of CBP manure from eight M...

  15. 21 CFR 890.5710 - Hot or cold disposable pack.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Hot or cold disposable pack. 890.5710 Section 890.5710 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Therapeutic Devices § 890.5710 Hot or...

  16. Battery pack circuit design for safety and protection

    SciTech Connect

    Dewey, M.; Chandler, D.; Tamura, A.

    1995-12-31

    Do our fast-paced lifestyles drive new technology, or is new technology partly to blame for continuing to increase the pace of our lifestyles? We want to be connected and productive - or entertained - even during our traditional times of leisure and recreation. Our tools for connectivity and productivity - and our toys for entertainment - support us by continuing to become smaller, lighter and more mobile, even as functionality increases. This drive toward increasing portability, mobility and functionality has had many interesting results. One result is that high-energy battery packs are becoming pervasive in our professional and personal lives. But the high power-delivery and energy-storage capabilities of packs for these power-hungry devices generally remain invisible to end-users. In reality, most packs have the potential not only for damaging themselves, but also for imposing damage on their surroundings, even if used exclusively in accordance with manufacturers` instructions. And newer battery technologies that offer longer runtimes or less weight can pose higher risks. This paper compares and contrasts the characteristics of various safety practices and devices used in designing and assembling high-energy battery packs.

  17. Packed rod neutron shield for fast nuclear reactors

    DOEpatents

    Eck, John E.; Kasberg, Alvin H.

    1978-01-01

    A fast neutron nuclear reactor including a core and a plurality of vertically oriented neutron shield assemblies surrounding the core. Each assembly includes closely packed cylindrical rods within a polygonal metallic duct. The shield assemblies are less susceptible to thermal stresses and are less massive than solid shield assemblies, and are cooled by liquid coolant flow through interstices among the rods and duct.

  18. Making One World: An Education Pack on Development and Environment.

    ERIC Educational Resources Information Center

    1992

    This pack contains activities aimed at 10-14 year-olds to help raise awareness of issues surrounding the environment and development and the concept of sustainable development. The Teachers' Notes outline the seven units of student activity sheets: (A) lifestyles (links between consumption, development, and the environment); (B) identifying the…

  19. 21 CFR 880.5760 - Chemical cold pack snakebite kit.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... snakebites. (b) Classification. Class III (premarket approval). (c) Date PMA or notice of completion of a PDP is required. A PMA or a notice of completion of a PDP is required to be filed with the Food and Drug... other chemical cold pack snakebite kit shall have an approved PMA or a declared completed PDP in...

  20. 21 CFR 880.5760 - Chemical cold pack snakebite kit.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... snakebites. (b) Classification. Class III (premarket approval). (c) Date PMA or notice of completion of a PDP is required. A PMA or a notice of completion of a PDP is required to be filed with the Food and Drug... other chemical cold pack snakebite kit shall have an approved PMA or a declared completed PDP in...

  1. Packing bunkers and piles to maximize forage preservation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Forage is a valuable commodity stored on dairy farms. Bunker and pile silos have increased in use due to increasing herd size. Losses in feed value in bunker and pile silos are frequently higher than they should be because producers are not packing them sufficiently to exclude oxygen during the stor...

  2. Social Interactions Sparked by Pictorial Warnings on Cigarette Packs

    PubMed Central

    Hall, Marissa G.; Peebles, Kathryn; Bach, Laura E.; Noar, Seth M.; Ribisl, Kurt M.; Brewer, Noel T.

    2015-01-01

    The Message Impact Framework suggests that social interactions may offer smokers the opportunity to process pictorial warnings on cigarette packs more deeply. We aimed to describe adult smokers’ social interactions about pictorial cigarette pack warnings in two longitudinal pilot studies. In Pilot Study 1, 30 smokers used cigarette packs with one of nine pictorial warnings for two weeks. In Pilot Study 2, 46 smokers used cigarette packs with one of five pictorial warnings for four weeks. Nearly all smokers (97%/96% in Pilot Study 1/2) talked about the warnings with other people, with the most common people being friends (67%/87%) and spouses/significant others (34%/42%). Pilot Study 2 found that 26% of smokers talked about the warnings with strangers. Discussions about the health effects of smoking and quitting smoking were more frequent during the first week of exposure to pictorial warnings than in the week prior to beginning the study (both p < 0.05). Pictorial warnings sparked social interactions about the warnings, the health effects of smoking, and quitting smoking, indicating that pictorial warnings may act as a social intervention reaching beyond the individual. Future research should examine social interactions as a potential mediator of the impact of pictorial warnings on smoking behavior. PMID:26506363

  3. 7 CFR 905.10 - Carton or standard packed carton.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 8 2013-01-01 2013-01-01 false Carton or standard packed carton. 905.10 Section 905.10 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS AND ORDERS; FRUITS, VEGETABLES, NUTS), DEPARTMENT OF AGRICULTURE...

  4. 7 CFR 905.10 - Carton or standard packed carton.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 8 2014-01-01 2014-01-01 false Carton or standard packed carton. 905.10 Section 905.10 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS AND ORDERS; FRUITS, VEGETABLES, NUTS), DEPARTMENT OF AGRICULTURE...

  5. 7 CFR 905.10 - Carton or standard packed carton.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Carton or standard packed carton. 905.10 Section 905.10 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE...

  6. 7 CFR 905.10 - Carton or standard packed carton.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 8 2012-01-01 2012-01-01 false Carton or standard packed carton. 905.10 Section 905.10 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE...

  7. 7 CFR 905.10 - Carton or standard packed carton.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 8 2011-01-01 2011-01-01 false Carton or standard packed carton. 905.10 Section 905.10 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE...

  8. 7 CFR 51.2840 - Export packing requirements.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 2 2011-01-01 2011-01-01 false Export packing requirements. 51.2840 Section 51.2840 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE REGULATIONS AND STANDARDS UNDER THE...

  9. Modeling water movement in beef cattle bedded manure pack

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Bedded manure is a valuable fertilizer source because it contains essential macronutrients (nitrogen (N), phosphorus (P), and potassium (K)) for crop production. Previous research with beef cattle bedded manure packs demonstrated that water-soluble macronutrients accumulated toward the bottom of the...

  10. 21 CFR 880.5760 - Chemical cold pack snakebite kit.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Chemical cold pack snakebite kit. 880.5760 Section 880.5760 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL HOSPITAL AND PERSONAL USE DEVICES General Hospital and Personal Use Therapeutic Devices § 880.5760 Chemical cold...

  11. Destabilization of confined granular packings due to fluid flow

    NASA Astrophysics Data System (ADS)

    Monloubou, Martin; Sandnes, Bjørnar

    2016-04-01

    Fluid flow through granular materials can cause fluidization when fluid drag exceeds the frictional stress within the packing. Fluid driven failure of granular packings is observed in both natural and engineered settings, e.g. soil liquefaction and flowback of proppants during hydraulic fracturing operations. We study experimentally the destabilization and flow of an unconsolidated granular packing subjected to a point source fluid withdrawal using a model system consisting of a vertical Hele-Shaw cell containing a water-grain mixture. The fluid is withdrawn from the cell at a constant rate, and the emerging flow patterns are imaged in time-lapse mode. Using Particle Image Velocimetry (PIV), we show that the granular flow gets localized in a narrow channel down the center of the cell, and adopts a Gaussian velocity profile similar to those observed in dry grain flows in silos. We investigate the effects of the experimental parameters (flow rate, grain size, grain shape, fluid viscosity) on the packing destabilization, and identify the physical mechanisms responsible for the observed complex flow behaviour.

  12. Social Interactions Sparked by Pictorial Warnings on Cigarette Packs.

    PubMed

    Hall, Marissa G; Peebles, Kathryn; Bach, Laura E; Noar, Seth M; Ribisl, Kurt M; Brewer, Noel T

    2015-10-01

    The Message Impact Framework suggests that social interactions may offer smokers the opportunity to process pictorial warnings on cigarette packs more deeply. We aimed to describe adult smokers' social interactions about pictorial cigarette pack warnings in two longitudinal pilot studies. In Pilot Study 1, 30 smokers used cigarette packs with one of nine pictorial warnings for two weeks. In Pilot Study 2, 46 smokers used cigarette packs with one of five pictorial warnings for four weeks. Nearly all smokers (97%/96% in Pilot Study 1/2) talked about the warnings with other people, with the most common people being friends (67%/87%) and spouses/significant others (34%/42%). Pilot Study 2 found that 26% of smokers talked about the warnings with strangers. Discussions about the health effects of smoking and quitting smoking were more frequent during the first week of exposure to pictorial warnings than in the week prior to beginning the study (both p < 0.05). Pictorial warnings sparked social interactions about the warnings, the health effects of smoking, and quitting smoking, indicating that pictorial warnings may act as a social intervention reaching beyond the individual. Future research should examine social interactions as a potential mediator of the impact of pictorial warnings on smoking behavior. PMID:26506363

  13. Rapidly falling costs of battery packs for electric vehicles

    NASA Astrophysics Data System (ADS)

    Nykvist, Björn; Nilsson, Måns

    2015-04-01

    To properly evaluate the prospects for commercially competitive battery electric vehicles (BEV) one must have accurate information on current and predicted cost of battery packs. The literature reveals that costs are coming down, but with large uncertainties on past, current and future costs of the dominating Li-ion technology. This paper presents an original systematic review, analysing over 80 different estimates reported 2007-2014 to systematically trace the costs of Li-ion battery packs for BEV manufacturers. We show that industry-wide cost estimates declined by approximately 14% annually between 2007 and 2014, from above US$1,000 per kWh to around US$410 per kWh, and that the cost of battery packs used by market-leading BEV manufacturers are even lower, at US$300 per kWh, and has declined by 8% annually. Learning rate, the cost reduction following a cumulative doubling of production, is found to be between 6 and 9%, in line with earlier studies on vehicle battery technology. We reveal that the costs of Li-ion battery packs continue to decline and that the costs among market leaders are much lower than previously reported. This has significant implications for the assumptions used when modelling future energy and transport systems and permits an optimistic outlook for BEVs contributing to low-carbon transport.

  14. Interior view of the trimming and packing tables, ginaca machines ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Interior view of the trimming and packing tables, ginaca machines deliver pineapples from the left to the tables, view facing east - Kahului Cannery, Plant No. 28, Cannery Building and Dryer House/Feed Storage Building, 120 Kane Street, Kahului, Maui County, HI

  15. 4. PACK TRAIN WAITING TO BE UNLOADED AT FOOT OF ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. PACK TRAIN WAITING TO BE UNLOADED AT FOOT OF YAKI TRAIL. APPROXIMATELY TWO-AND-ONE-HALF TONS OF STEEL ON ANIMALS SHOWN. NOTE COIL OF 1-1/2' WIND CABLE IN FOREGROUND. - Kaibab Trail Suspension Bridge, Spanning Colorado River, Grand Canyon, Coconino County, AZ

  16. Frac-and-pack stimulation: Application, design, and field experience

    SciTech Connect

    Roodhart, L.P.; Fokker, P.A.; Davies, D.R.; Shlyapobersky, J.; Wong, G.K.

    1994-03-01

    This paper discusses the criteria for selecting wells to be frac-and-packed. The authors show how systematic study of the inflow performance can be used to assess the potential of frac-and-packed wells, to identify the controlling factors, and to optimize design parameters. They also show that fracture conductivity is often the key to successful treatment. This conductivity depends largely on proppant size; formation permeability damage around the created fracture has less effect. Appropriate allowance needs to be made for flow restrictions caused by the presence of the perforations, partial penetration, and non-Darcy effects. They describe the application of the overpressure-calibrated hydraulic fracture model in frac-and-pack treatment design, and discuss some operational considerations with reference to field examples. The full potential of this promising new completion method can be achieved only if the design is tailored to the individual well. This demands high-quality input data, which can be obtained only from a calibration test. This paper presents their strategy for frac-and-pack design, drawing on examples from field experience. They also point out several areas that the industry needs to address, such as the sizing of proppant in soft formations and the interaction between fracturing fluids and resin in resin-coated proppant.

  17. Hydrodynamics of Packed Bed Reactor in Low Gravity

    NASA Technical Reports Server (NTRS)

    Motil, Brian J.; Nahra, Henry K.; Balakotaiah, Vemuri

    2005-01-01

    Packed bed reactors are well known for their vast and diverse applications in the chemical industry; from gas absorption, to stripping, to catalytic conversion. Use of this type of reactor in terrestrial applications has been rather extensive because of its simplicity and relative ease of operation. Developing similar reactors for use in microgravity is critical to many space-based advanced life support systems. However, the hydrodynamics of two-phase flow packed bed reactors in this new environment and the effects of one physiochemical process on another has not been adequately assessed. Surface tension or capillary forces play a much greater role which results in a shifting in flow regime transitions and pressure drop. Results from low gravity experiments related to flow regimes and two-phase pressure drop models are presented in this paper along with a description of plans for a flight experiment on the International Space Station (ISS). Understanding the packed bed hydrodynamics and its effects on mass transfer processes in microgravity is crucial for the design of packed bed chemical or biological reactors to be used for water reclamation and other life support processes involving water purification.

  18. 21 CFR 133.124 - Cold-pack cheese food.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... acidifying agent consisting of one or any mixture of two or more of the following: A vinegar, lactic acid, citric acid, acetic acid, and phosphoric acid, in such quantity that the pH of the finished cold-pack... consisting of sorbic acid, potassium sorbate, sodium sorbate, or any combination of two or more of these,...

  19. The Assignment Pack. Materials for Flexible and Open Learning.

    ERIC Educational Resources Information Center

    Adult Literacy and Basic Skills Unit, London (England).

    This assignment pack is designed for students and tutors working in open, flexible, or distance learning in Britain. Each of the six sections contains the following: (1) a detailed contents page that identifies the assignment under an activity heading, an individual title, and indication of the relationship to the City and Guilds of London…

  20. 7 CFR 319.37-9 - Approved packing material.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Agriculture Regulations of the Department of Agriculture (Continued) ANIMAL AND PLANT HEALTH INSPECTION..., and Other Plant Products 1,2 § 319.37-9 Approved packing material. Any restricted article at the time... material is free from sand, soil, or earth (except for sand designated below); has not been used...

  1. 7 CFR 319.37-9 - Approved packing material.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Agriculture Regulations of the Department of Agriculture (Continued) ANIMAL AND PLANT HEALTH INSPECTION..., and Other Plant Products 1,2 § 319.37-9 Approved packing material. Any restricted article at the time... material is free from sand, soil, or earth (except for sand designated below); has not been used...

  2. 7 CFR 319.37-9 - Approved packing material.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... additional declaration from the plant protection service of Bermuda that such sand was free from soil... Agriculture Regulations of the Department of Agriculture (Continued) ANIMAL AND PLANT HEALTH INSPECTION... material immediately prior to shipment; such packing material is free from sand, soil, or earth (except...

  3. 7 CFR 319.37-9 - Approved packing material.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... additional declaration from the plant protection service of Bermuda that such sand was free from soil... Agriculture Regulations of the Department of Agriculture (Continued) ANIMAL AND PLANT HEALTH INSPECTION... material immediately prior to shipment; such packing material is free from sand, soil, or earth (except...

  4. 7 CFR 319.37-9 - Approved packing material.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... additional declaration from the plant protection service of Bermuda that such sand was free from soil... Agriculture Regulations of the Department of Agriculture (Continued) ANIMAL AND PLANT HEALTH INSPECTION... material immediately prior to shipment; such packing material is free from sand, soil, or earth (except...

  5. Supramolecular Packing Controls H₂ Photocatalysis in Chromophore Amphiphile Hydrogels.

    PubMed

    Weingarten, Adam S; Kazantsev, Roman V; Palmer, Liam C; Fairfield, Daniel J; Koltonow, Andrew R; Stupp, Samuel I

    2015-12-01

    Light harvesting supramolecular assemblies are potentially useful structures as components of solar-to-fuel conversion materials. The development of these functional constructs requires an understanding of optimal packing modes for chromophores. We investigated here assembly in water and the photocatalytic function of perylene monoimide chromophore amphiphiles with different alkyl linker lengths separating their hydrophobic core and the hydrophilic carboxylate headgroup. We found that these chromophore amphiphiles (CAs) self-assemble into charged nanostructures of increasing aspect ratio as the linker length is increased. The addition of salt to screen the charged nanostructures induced the formation of hydrogels and led to internal crystallization within some of the nanostructures. For linker lengths up to seven methylenes, the CAs were found to pack into 2D crystalline unit cells within ribbon-shaped nanostructures, whereas the nine methylene CAs assembled into long nanofibers without crystalline molecular packing. At the same time, the different molecular packing arrangements after charge screening led to different absorbance spectra, despite the identical electronic properties of all PMI amphiphiles. While the crystalline CAs formed electronically coupled H-aggregates, only CAs with intermediate linker lengths showed evidence of high intermolecular orbital overlap. Photocatalytic hydrogen production using a nickel-based catalyst was observed in all hydrogels, with the highest turnovers observed for CA gels having intermediate linker lengths. We conclude that the improved photocatalytic performance of the hydrogels formed by supramolecular assemblies of the intermediate linker CA molecules likely arises from improved exciton splitting efficiencies due to their higher orbital overlap. PMID:26593389

  6. Packing and stability of geometrically cohesive granular media

    NASA Astrophysics Data System (ADS)

    Gravish, Nick; Franklin, Scott V.; Hu, David L.; Goldman, Daniel I.

    2011-11-01

    Granular particles with concave shapes may entangle with neighboring particles creating an effective cohesion controlled by particle geometry. We study the packing and stability of vertical columns formed from geometrically cohesive u-shaped particles (staples) of varying barb length, l. We prepare cohesive columns by packing particles in a confining cylindrical tube under vertical vibration at fixed frequency of f = 30 Hz and peak acceleration (in units of g) of Γ = 2 . The initial and final volume fraction vary with l and volume fraction increases for decreasing l. Once packed, the tube is removed and columns are subjected to vertical vibration at fixed f and variable Γ. We monitor column height, h (t) , during collapse and find that h (t) is described by a stretched exponential h (t) /h0 = exp [ -(t/τ)β ] . The characteristic collapse time, τ, is governed by an Arrhenius law with τ =τ0 exp (Γ0 / Γ) where Γ0 is a measure of the column's resistance to collapse. We find that Γ0 is a non-monotonic function of l and exhibits a maximum at intermediate l. We explain this effect through a model considering packing and entanglement.

  7. Cigarette pack design and adolescent smoking susceptibility: a cross-sectional survey

    PubMed Central

    Ford, Allison; MacKintosh, Anne Marie; Moodie, Crawford; Richardson, Sol; Hastings, Gerard

    2013-01-01

    Objectives To compare adolescents’ responses to three different styles of cigarette packaging: novelty (branded packs designed with a distinctive shape, opening style or bright colour), regular (branded pack with no special design features) and plain (brown pack with a standard shape and opening and all branding removed, aside from brand name). Design Cross-sectional in-home survey. Setting UK. Participants Random location quota sample of 1025 never smokers aged 11–16 years. Main outcome measures Susceptibility to smoking and composite measures of pack appraisal and pack receptivity derived from 11 survey items. Results Mean responses to the three pack types were negative for all survey items. However, ‘novelty’ packs were rated significantly less negatively than the ‘regular’ pack on most items, and the novelty and regular packs were rated less negatively than the ‘plain’ pack. For the novelty packs, logistic regressions, controlling for factors known to influence youth smoking, showed that susceptibility was associated with positive appraisal and also receptivity. For example, those receptive to the innovative Silk Cut Superslims pack were more than four times as likely to be susceptible to smoking than those not receptive to this pack (AOR=4.42, 95% CI 2.50 to 7.81, p<0.001). For the regular pack, an association was found between positive appraisal and susceptibility but not with receptivity and susceptibility. There was no association with pack appraisal or receptivity for the plain pack. Conclusions Pack structure (shape and opening style) and colour are independently associated, not just with appreciation of and receptivity to the pack, but also with susceptibility to smoke. In other words, those who think most highly of novelty cigarette packaging are also the ones who indicate that they are most likely to go on to smoke. Plain packaging, in contrast, was found to directly reduce the appeal of smoking to adolescents. PMID:24056481

  8. Body Imaging

    NASA Technical Reports Server (NTRS)

    1990-01-01

    Magnetic Resonance Imaging (MRI) and Computer-aided Tomography (CT) images are often complementary. In most cases, MRI is good for viewing soft tissue but not bone, while CT images are good for bone but not always good for soft tissue discrimination. Physicians and engineers in the Department of Radiology at the University of Michigan Hospitals are developing a technique for combining the best features of MRI and CT scans to increase the accuracy of discriminating one type of body tissue from another. One of their research tools is a computer program called HICAP. The program can be used to distinguish between healthy and diseased tissue in body images.

  9. Reporting accuracy of packed lunch consumption among Danish 11-year-olds differ by gender

    PubMed Central

    Lyng, Nina; Fagt, Sisse; Davidsen, Michael; Hoppe, Camilla; Holstein, Bjørn; Tetens, Inge

    2013-01-01

    Background Packed lunch is the dominant lunch format in many countries including Denmark. School lunch is consumed unsupervised, and self-reported recalls are appropriate in the school setting. However, little is known about the accuracy of recalls in relation to packed lunch. Objective To assess the qualitative recall accuracy of self-reported consumption of packed lunch among Danish 11-year-old children in relation to gender and dietary assessment method. Design A cross-sectional dietary recall study of packed lunch consumption. Digital images (DIs) served as an objective reference method to determine food items consumed. Recalls were collected with a lunch recall questionnaire (LRQ) comprising an open-ended recall (OE-Q) and a pre-coded food group prompted recall (PC-Q). Individual interviews (INTs) were conducted successively. The number of food items was identified and accuracy was calculated as match rates (% identified by DIs and reported correctly) and intrusion rates (% not identified by DIs but reported) were determined. Setting and subjects Three Danish public schools from Copenhagen. A total of 114 Danish 11-year-old children, mean (SE) age=11.1 (0.03), and body mass index=18.2 (0.26). Results The reference (DIs) showed that girls consumed a higher number of food items than boys [mean (SE) 5.4 (0.25) vs. 4.6 (0.29) items (p=0.05)]. The number of food items recalled differed between genders with OE-Q recalls (p=0.005) only. Girls’ interview recalls were more accurate than boys’ with higher match rates (p=0.04) and lower intrusion rates (p=0.05). Match rates ranged from 67–90% and intrusion rates ranged from 13–39% with little differences between girls and boys using the OE-Q and PC-Q methods. Conclusion Dietary recall validation studies should not only consider match rates as an account of accuracy. Intrusions contribute to over-reporting in non-validation studies, and future studies should address recall accuracy and inaccuracies in relation to

  10. Functionally Relevant Specific Packing Can Determine Protein Folding Routes.

    PubMed

    Yadahalli, Shilpa; Gosavi, Shachi

    2016-01-29

    Functional residues can modulate the folding mechanisms of proteins. In some proteins, mutations to such residues can radically change the primary folding route. Is it possible then to learn more about the functional regions of a protein by investigating just its choice of folding route? The folding and the function of the protein Escherichia coli ribonuclease H (ecoRNase-H) have been extensively studied and its folding route is known to near-residue resolution. Here, we computationally study the folding of ecoRNase-H using molecular dynamics simulations of structure-based models of increasing complexity. The differences between a model that correctly predicts the experimentally determined folding route and a simpler model that does not can be attributed to a set of six aromatic residues clustered together in a region of the protein called CORE. This clustering, which we term "specific" packing, drives CORE to fold early and determines the folding route. Both the residues involved in specific packing and their packing are largely conserved across E. coli-like RNase-Hs from diverse species. Residue conservation is usually implicated in function. Here, the identified residues either are known to bind substrate in ecoRNase-H or pack against the substrate in the homologous human RNase-H where a substrate-bound crystal structure exists. Thus, the folding mechanism of ecoRNase-H is a byproduct of functional demands upon its sequence. Using our observations on specific packing, we suggest mutations to an engineered HIV RNase-H to make its function better. Our results show that understanding folding route choice in proteins can provide unexpected insights into their function. PMID:26724535

  11. Body Levers.

    ERIC Educational Resources Information Center

    Chiappetta, Eugene L.

    1987-01-01

    Explains how the muscle and bone arrangement of the human body can be used in teaching the principles of simple machines. Presents an activity that investigates the lever system of the forearm. Includes background information on levers and suggests questions for classroom discussion. (ML)

  12. Analysis of a fully packed loop model arising in a magnetic Coulomb phase.

    PubMed

    Jaubert, L D C; Haque, M; Moessner, R

    2011-10-21

    The Coulomb phase of spin ice, and indeed the I(c) phase of water ice, naturally realize a fully packed two-color loop model in 3D. We present a detailed analysis of the statistics of these loops: we find loops spanning the system multiple times hosting a finite fraction of all sites while the average loop length remains finite. We contrast the behavior with an analogous 2D model. We connect this body of results to properties of polymers, percolation and insights from Schramm-Loewner evolution processes. We also study another extended degree of freedom, called worms, which appear as "Dirac strings" in spin ice. We discuss implications of these results for the efficiency of numerical cluster algorithms, and address implications for the ordering properties of a broader class of magnetic systems, e.g., with Heisenberg spins, such as CsNiCrF(6) or ZnCr(2)O(4). PMID:22107573

  13. Capillary self-assembly of floating bodies

    NASA Astrophysics Data System (ADS)

    Jung, Sunghwan; Thompson, Paul; Bush, John

    2007-11-01

    We study the self-assembly of bodies supported on the water surface by surface tension. Attractive and repulsive capillary forces exist between menisci of, respectively, the same and opposite signs. In nature, floating objects (e.g. mosquito larvae) thus interact through capillary forces to form coherent packings on the water surface. We here present the results of an experimental investigation of such capillary pattern formation. Thin elliptical metal sheets were designed to have variable shape, flexibility and mass distribution. On the water surface, mono-, bi-, or tri-polar menisci could thus be achieved. The influence of the form of the menisci on the packings arising from the interaction of multiple floaters is explored. Biological applications are discussed.

  14. [Body-packer & body-stuffer - a medical challenge].

    PubMed

    Gsell, M; Perrig, M; Eichelberger, M; Chatterjee, B; Stoll, U; Stanga, Z

    2010-04-28

    Since the seventies, the practice of drug smuggling in the form of body packing has increased in the Western world. The goal of our study was to present an algorithm for the safe management of intracorporal drug transport based on clinical experience and current evidence. The retrospective study, conducted over the past four years in our hospital prison, analyzes and discusses the diagnostic and therapeutic concepts. Thirty-four patients hospitalized 37 times in a 48-month period were included. In 28 patients drug packages were identified. Only two patients suffered from serious complications. The study demonstrates that following a specifically designed management algorithm based on clinical experience and principles of evidence-based medicine can optimize risk management, improve quality assurance and patient safety. PMID:20449821

  15. [Body contouring].

    PubMed

    Krüger, N; Lübberding, S; Sattler, G

    2015-10-01

    In our contemporary postmodern society, a modified perception of the human body is accompanied by an increasing demand for body shaping procedures. The treatment needs to be effective but it is just as important that they are safe and can be easily integrated into the daily working and routine schedule. While the options for minimally invasive volume addition are largely limited to injectable implants based on hyaluronic acid or autologous fat, a multitude of options are available for volume reduction. Before deciding on the method of choice, the following needs to be considered: which indications need to be treated, the extent of the reduction in volume and how much pain and possible undesired reactions the patient is prepared to accept. PMID:26349684

  16. 48 CFR 252.211-7004 - Alternate preservation, packaging, and packing.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... package gross weight and dimensions; (x) Packing; and (xi) Packing gross weight and dimensions; and (4) Item characteristics, to include— (i) Material and finish; (ii) Net weight; (iii) Net dimensions;...

  17. CTEPP STANDARD OPERATING PROCEDURE FOR PACKING AND SHIPPING STUDY SAMPLES (SOP-3.11)

    EPA Science Inventory

    This SOP describes the methods for packing and shipping study samples. These methods are for packing and shipping biological and environmental samples. The methods have been tested and used in the previous pilot studies.

  18. Comparison of the biological H2S removal characteristics among four inorganic packing materials.

    PubMed

    Hirai, M; Kamamoto, M; Yani, M; Shoda, M

    2001-01-01

    Four inorganic packing materials were evaluated in terms of their availability as packing materials of a packed tower deodorization apparatus (biofilter) from the viewpoints of biological H2S removal characteristics and some physical properties. Among porous ceramics (A), calcinated cristobalite (B), calcinated and formed obsidian (C), granulated and calcinated soil (D), the superiority of these packing materials determined based on the values of non-biological removal per unit weight or unit volume of packing material, complete removal capacity of H2S per unit weight of packing material per day or unit volume of packing material per day and pressure drop of the packed bed was in the order of A approximately equal to C > D approximately equal to B, which is correlated with the maximum water content, porosity, and mean pore diameter. PMID:16233011

  19. Marginal rigidity and history dependence in packings of attractive athermal emulsions

    NASA Astrophysics Data System (ADS)

    Bargteil, Dylan; Pontani, Lea-Laetitia; Brujic, Jasna

    2014-03-01

    The geometry and stress through particulate packings depends on the method of preparation and the interaction potential between the particles. Previously, we discovered that creaming frictionless, athermal emulsions with a short-range depletion attraction leads to an initial increase in the packing density above random close packing, followed by a monotonic decrease in density (Jorjadze et al, PNAS, 2011). This decrease is because the attractive force stabilizes loose voids, thus reducing the average coordination number, , of the packing. In order to understand the mechanism of packing creation, we investigate whether the final density is influenced by the polydispersity or the initial volume fraction of droplets, as it is in frictional packings. Finally, we compress the attractive packings by centrifugation to probe the scaling laws of pressure versus density and and compare them with those found in repulsive packings (Jorjadze et al, PRL, 2013).

  20. Homochiral 3D metal-organic frameworks from chiral 1D rods: 6-way helical packing.

    PubMed

    Shin, Sung Min; Moon, Dohyun; Jeong, Kyung Seok; Kim, Jaheon; Thallapally, Praveen K; Jeong, Nakcheol

    2011-09-01

    The chiral 3D MOFs resulted from the packing of chiral 1D SBBs were studied. It was demonstrated that the final packing pattern is sensitively dependent on the dimension of SBBs. In addition, we were able to identify a new plywood-like network from ligand 2H(2) exhibiting an unprecedented six-way chiral helical packing motif, which extends the list of invariant rod packings. PMID:21773637

  1. Mobility of icy sand packs, with application to Martian permafrost

    USGS Publications Warehouse

    Durham, W.B.; Pathare, A.V.; Stern, L.A.; Lenferink, H.J.

    2009-01-01

    [1] The physical state of water on Mars has fundamental ramifications for both climatology and astrobiology. The widespread presence of "softened" Martian landforms (such as impact craters) can be attributed to viscous creep of subsurface ground ice. We present laboratory experiments designed to determine the minimum amount of ice necessary to mobilize topography within Martian permafrost. Our results show that the jammed-to-mobile transition of icy sand packs neither occurs at fixed ice content nor is dependent on temperature or stress, but instead correlates strongly with the maximum dry packing density of the sand component. Viscosity also changes rapidly near the mobility transition. The results suggest a potentially lower minimum volatile inventory for the impact-pulverized megaregolith of Mars. Furthermore, the long-term preservation of partially relaxed craters implies that the ice content of Martian permafrost has remained close to that at the mobility transition throughout Martian history. Copyright 2009 by the American Geophysical Union.

  2. Spontaneous formation of densely packed shear bands of rotating fragments.

    PubMed

    Åström, J A; Timonen, J

    2012-05-01

    Appearance of self-similar space-filling ball bearings has been suggested to provide the explanation for seismic gaps, shear weakness, and lack of detectable frictional heat formation in mature tectonic faults (shear zones). As the material in a shear zone fractures and grinds, it could be thought to eventually form a conformation that allows fragments to largely roll against each other without much sliding. This type of space-filling "ball bearing" can be constructed artificially, but so far how such delicate structures may appear spontaneously has remained unexplained. It is demonstrated here that first-principles simulations of granular packing with fragmenting grains indeed display spontaneous formation of shear bands with fragment conformations very similar to those of densely packed ball bearings. PMID:22644135

  3. An unusual case of predation: dog pack or cougar attack?

    PubMed

    Fonseca, Gabriel M; Palacios, Rocío

    2013-01-01

    Injuries produced by animals are capable of leaving severe patterns and in some cases may result in the death of the attacked individual. Law enforcement authorities may come to erroneous conclusions about the source of the bites based on their awareness of animals present and similarities of the injuries to the untrained eye, with dreadful consequences. Expertise of a carnivore biologist and an odontologist that indentifies the particularities of bite marks may be useful for identifying the attacking species. We present the investigation of a fatal dog pack attack involving a 43-year-old man in Bell Ville (Argentina) where the evidence provided by a forensic dentist and a biologist was categorical for establishing the animal species involved. Because of the unusual characteristics of the wounds and the initial hypothesis made by local authorities of a cougar attack, habits and specific patterns of both dog pack and cougar predation on humans are discussed. PMID:22971181

  4. Accumulation of BSA in Packed-bed Microfluidics

    NASA Astrophysics Data System (ADS)

    Summers, Samantha; Hu, Chuntian; Hartman, Ryan

    2012-11-01

    Alzheimers and Parkinsons are two diseases that are associated with protein deposition in the brain, causing loss of either cognitive or muscle functioning. Protein deposition diseases are considered progressive diseases since the continual aggregation of protein causes the patient's symptoms to slowly worsen over time. There are currently no known means of treatment for protein deposition diseases. Our goal is to understand the potential for packed-bed microfluidics to study protein accumulation. Measurement of the resistance to flow through micro-scale packed-beds is critical to understanding the process of protein accumulation. Aggregation in bulk is fundamentally different from accumulation on surfaces. Our study attempts to distinguish between either mechanism. The results from our experiments involving protein injection through a microfluidic system will be presented and discussed. Funding received by NSF REU Grant 1062611.

  5. A worm algorithm for the fully-packed loop model

    NASA Astrophysics Data System (ADS)

    Zhang, Wei; Garoni, Timothy M.; Deng, Youjin

    2009-06-01

    We present a Markov-chain Monte Carlo algorithm of worm type that correctly simulates the fully-packed loop model with n=1 on the honeycomb lattice, and we prove that it is ergodic and has uniform stationary distribution. The honeycomb-lattice fully-packed loop model with n=1 is equivalent to the zero-temperature triangular-lattice antiferromagnetic Ising model, which is fully frustrated and notoriously difficult to simulate. We test this worm algorithm numerically and estimate the dynamic exponent z=0.515(8). We also measure several static quantities of interest, including loop-length and face-size moments. It appears numerically that the face-size moments are governed by the magnetic dimension for percolation.

  6. Close-packed array of light emitting devices

    DOEpatents

    Ivanov, Ilia N.; Simpson, John T.

    2013-04-09

    A close-packed array of light emitting diodes includes a nonconductive substrate having a plurality of elongate channels extending therethrough from a first side to a second side, where each of the elongate channels in at least a portion of the substrate includes a conductive rod therein. The conductive rods have a density over the substrate of at least about 1,000 rods per square centimeter and include first conductive rods and second conductive rods. The close-packed array further includes a plurality of light emitting diodes on the first side of the substrate, where each light emitting diode is in physical contact with at least one first conductive rod and in electrical contact with at least one second conductive rod.

  7. Operation of Packed-Bed Reactors Studied in Microgravity

    NASA Technical Reports Server (NTRS)

    Motil, Brian J.; Balakotaiah, Vemuri

    2004-01-01

    The operation of a packed bed reactor (PBR) involves gas and liquid flowing simultaneously through a fixed-bed of solid particles. Depending on the application, the particles can be various shapes and sizes but are generally designed to force the two fluid phases through a tortuous route of narrow channels connecting the interstitial space. The PBR is the most common type of reactor in industry because it provides for intimate contact and high rates of transport between the phases needed to sustain chemical or biological reactions. The packing may also serve as either a catalyst or as a support for growing biological material. Furthermore, this type of reactor is relatively compact and requires minimal power to operate. This makes it an excellent candidate for unit operations in support of long-duration human space activities.

  8. Molecular packing in bone collagen fibrils prior to mineralization

    NASA Astrophysics Data System (ADS)

    Hsiao, Benjamin; Zhou, Hong-Wen; Burger, Christian; Chu, Benjamin; Glimcher, Melvin J.

    2012-02-01

    The three-dimensional packing of collagen molecules in bone collagen fibrils has been largely unknown because even in moderately mineralized bone tissues, the organic matrix structure is severely perturbed by the deposition of mineral crystals. During the past decades, the structure of tendon collagen (e.g. rat tail) --- a tissue that cannot mineralize in vivo, has been assumed to be representative for bone collagen fibrils. Small-angle X-ray diffraction analysis of the native, uncalcified intramuscular fish bone has revealed a new molecular packing scheme, significantly different from the quasi-hexagonal arrangement often found in tendons. The deduced structure in bone collagen fibrils indicates the presence of spatially discrete microfibrils, and an arrangement of intrafibrillar space to form ``channels'', which could accommodate crystals with dimensions typically found in bone apatite.

  9. When do jammed sphere packings have a valid linear regime?

    NASA Astrophysics Data System (ADS)

    Goodrich, Carl; Liu, Andrea; Nagel, Sidney

    2014-03-01

    The physics of jamming can be studied in its purest form in packings of soft spheres at zero temperature. One of the successes of this approach is that bulk material properties, such as the elastic moduli or density of normal modes, can be predicted solely from the distance of the system to the jamming transition. Such properties are both defined and measured in the linear-response regime. It is thus tacitly assumed that the harmonic approximation to the local energy landscape can capture the meaningful physics, and it is therefore essential to delineate when this assumption is valid. We will examine the regime of validity of the harmonic approximation in jammed sphere packings as a function of system size and density. We will also discuss the crossover from linear response of the zero-temperature jammed solid to thermal behavior at nonzero temperatures.

  10. Activated chemoreceptor arrays remain intact and hexagonally packed

    PubMed Central

    Briegel, Ariane; Beeby, Morgan; Thanbichler, Martin; Jensen, Grant J.

    2013-01-01

    Summary Bacterial chemoreceptors cluster into exquisitively sensitive, tunable, highly ordered, polar arrays. While these arrays serve as paradigms of cell signalling in general, it remains unclear what conformational changes transduce signals from the periplasmic tips, where attractants and repellents bind, to the cytoplasmic signalling domains. Conflicting reports support and contest the hypothesis that activation causes large changes in the packing arrangement of the arrays, up to and including their complete disassembly. Using electron cryotomography, here we show that in Caulobacter crescentus, chemoreceptor arrays in cells grown in different media and immediately after exposure to the attractant galactose all exhibit the same 12 nm hexagonal packing arrangement, array size and other structural parameters. ΔcheB and ΔcheR mutants mimicking attractant- or repellent-bound states prior to adaptation also show the same lattice structure. We conclude that signal transduction and amplification must be accomplished through only small, nanoscale conformational changes. PMID:21992450

  11. Phyllotaxis, Pushed Pattern-Forming Fronts, and Optimal Packing

    NASA Astrophysics Data System (ADS)

    Pennybacker, Matthew; Newell, Alan C.

    2013-06-01

    We demonstrate that the pattern forming partial differential equation derived from the auxin distribution model proposed by Meyerowitz, Traas, and others gives rise to all spiral phyllotaxis properties observed on plants. We show how the advancing pushed pattern front chooses spiral families enumerated by Fibonacci sequences with all attendant self-similar properties, a new amplitude invariant curve, and connect the results with the optimal packing based algorithms previously used to explain phyllotaxis. Our results allow us to make experimentally testable predictions.

  12. Biomass growth restriction in a packed bed reactor

    DOEpatents

    Griffith, William L.; Compere, Alicia L.

    1978-01-01

    When carrying out continuous biologically catalyzed reactions with anaerobic microorganisms attached to a support in an upflow packed bed column, growth of the microorganisms is restricted to prevent the microorganisms from plugging the column by limiting the availability of an essential nutrient and/or by the presence of predatory protozoa which consume the anaerobic microorganisms. A membrane disruptive detergent may be provided in the column to lyse dead microorganisms to make them available as nutrients for live microorganisms.

  13. 75 FR 31283 - Clarification of Parachute Packing Authorization

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-03

    ...This action amends the requirements for individuals who pack, maintain, or alter main parachutes of a dual-parachute system--those with main and ``back up'' parachutes--to be used for parachute jumping in connection with civil aircraft of the United States. It expressly limits the authority of a non-certificated person who is not under the supervision of an appropriate current certificated......

  14. Distribution of breakage events in random packings of rodlike particles

    NASA Astrophysics Data System (ADS)

    Grof, Zdeněk; Štěpánek, František

    2013-07-01

    Uniaxial compaction and breakage of rodlike particle packing has been studied using a discrete element method simulation. A scaling relationship between the applied stress, the number of breakage events, and the number-mean particle length has been derived and compared with computational experiments. Based on results for a wide range of intrinsic particle strengths and initial particle lengths, it seems that a single universal relation can be used to describe the incidence of breakage events during compaction of rodlike particle layers.

  15. Existence of isostatic, maximally random jammed monodisperse hard-disk packings

    PubMed Central

    Atkinson, Steven; Stillinger, Frank H.; Torquato, Salvatore

    2014-01-01

    We generate jammed packings of monodisperse circular hard-disks in two dimensions using the Torquato–Jiao sequential linear programming algorithm. The packings display a wide diversity of packing fractions, average coordination numbers, and order as measured by standard scalar order metrics. This geometric-structure approach enables us to show the existence of relatively large maximally random jammed (MRJ) packings with exactly isostatic jammed backbones and a packing fraction (including rattlers) of ϕ=0.826. By contrast, the concept of random close packing (RCP) that identifies the most probable packings as the most disordered misleadingly identifies highly ordered disk packings as RCP in 2D. Fundamental structural descriptors such as the pair correlation function, structure factor, and Voronoi statistics show a strong contrast between the MRJ state and the typical hyperstatic, polycrystalline packings with ϕ≈0.88 that are more commonly obtained using standard packing protocols. Establishing that the MRJ state for monodisperse hard disks is isostatic and qualitatively distinct from commonly observed polycrystalline packings contradicts conventional wisdom that such a disordered, isostatic packing does not exist due to a lack of geometrical frustration and sheds light on the nature of disorder. This prompts the question of whether an algorithm may be designed that is strongly biased toward generating the monodisperse disk MRJ state. PMID:25512529

  16. 7 CFR 51.691 - Standard pack for oranges except Temple variety.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 2 2011-01-01 2011-01-01 false Standard pack for oranges except Temple variety. 51..., CERTIFICATION, AND STANDARDS) United States Standards for Grades of Oranges (Texas and States Other Than Florida, California, and Arizona) Standard Pack § 51.691 Standard pack for oranges except Temple variety. (a)...

  17. 7 CFR 51.691 - Standard pack for oranges except Temple variety.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Standard pack for oranges except Temple variety. 51..., CERTIFICATION, AND STANDARDS) United States Standards for Grades of Oranges (Texas and States Other Than Florida, California, and Arizona) Standard Pack § 51.691 Standard pack for oranges except Temple variety. (a)...

  18. 7 CFR 51.691 - Standard pack for oranges except Temple variety.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 2 2012-01-01 2012-01-01 false Standard pack for oranges except Temple variety. 51..., CERTIFICATION, AND STANDARDS) United States Standards for Grades of Oranges (Texas and States Other Than Florida, California, and Arizona) Standard Pack § 51.691 Standard pack for oranges except Temple variety. (a)...

  19. Existence of isostatic, maximally random jammed monodisperse hard-disk packings.

    PubMed

    Atkinson, Steven; Stillinger, Frank H; Torquato, Salvatore

    2014-12-30

    We generate jammed packings of monodisperse circular hard-disks in two dimensions using the Torquato-Jiao sequential linear programming algorithm. The packings display a wide diversity of packing fractions, average coordination numbers, and order as measured by standard scalar order metrics. This geometric-structure approach enables us to show the existence of relatively large maximally random jammed (MRJ) packings with exactly isostatic jammed backbones and a packing fraction (including rattlers) of [Formula: see text]. By contrast, the concept of random close packing (RCP) that identifies the most probable packings as the most disordered misleadingly identifies highly ordered disk packings as RCP in 2D. Fundamental structural descriptors such as the pair correlation function, structure factor, and Voronoi statistics show a strong contrast between the MRJ state and the typical hyperstatic, polycrystalline packings with [Formula: see text] that are more commonly obtained using standard packing protocols. Establishing that the MRJ state for monodisperse hard disks is isostatic and qualitatively distinct from commonly observed polycrystalline packings contradicts conventional wisdom that such a disordered, isostatic packing does not exist due to a lack of geometrical frustration and sheds light on the nature of disorder. This prompts the question of whether an algorithm may be designed that is strongly biased toward generating the monodisperse disk MRJ state. PMID:25512529

  20. 48 CFR 252.211-7004 - Alternate preservation, packaging, and packing.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ..., packaging, and packing. 252.211-7004 Section 252.211-7004 Federal Acquisition Regulations System DEFENSE... CLAUSES Text of Provisions And Clauses 252.211-7004 Alternate preservation, packaging, and packing. As prescribed in 211.272, use the following provision: Alternate Preservation, Packaging, and Packing (DEC...

  1. 48 CFR 252.211-7004 - Alternate preservation, packaging, and packing.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ..., packaging, and packing. 252.211-7004 Section 252.211-7004 Federal Acquisition Regulations System DEFENSE... CLAUSES Text of Provisions And Clauses 252.211-7004 Alternate preservation, packaging, and packing. As prescribed in 211.272, use the following provision: Alternate Preservation, Packaging, and Packing (DEC...

  2. 48 CFR 252.211-7004 - Alternate preservation, packaging, and packing.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ..., packaging, and packing. 252.211-7004 Section 252.211-7004 Federal Acquisition Regulations System DEFENSE... CLAUSES Text of Provisions And Clauses 252.211-7004 Alternate preservation, packaging, and packing. As prescribed in 211.272, use the following provision: Alternate Preservation, Packaging, and Packing (DEC...

  3. 48 CFR 252.211-7004 - Alternate preservation, packaging, and packing.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ..., packaging, and packing. 252.211-7004 Section 252.211-7004 Federal Acquisition Regulations System DEFENSE... CLAUSES Text of Provisions And Clauses 252.211-7004 Alternate preservation, packaging, and packing. As prescribed in 211.272, use the following provision: Alternate Preservation, Packaging, and Packing (DEC...

  4. 19 CFR 10.540 - Packing materials and containers for shipment.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 19 Customs Duties 1 2010-04-01 2010-04-01 false Packing materials and containers for shipment. 10...-Singapore Free Trade Agreement Rules of Origin § 10.540 Packing materials and containers for shipment. (a) Packing materials and containers for shipment, as defined in § 10.530(j) of this subpart, are to...

  5. Gradient packing bed bio-filter for landfill methane mitigation.

    PubMed

    Obulisamy, Parthiba Karthikeyan; Sim Yan May, Jane; Rajasekar, Balasubramanian

    2016-10-01

    We assessed the suitability of various biogenic materials for development of a gradient packed bed bio-filter to mitigate the methane (CH4) emission from landfills. Five different biogenic materials (windrow compost-WC; vermicompost-VC; landfill top cover-LTC; landfill bottom soil-LBS; and river soil sediment-SS) were screened. Among these materials, the VC showed a better CH4 oxidation potential (MOP) of 12.6μg CH4 gdw(-1)h(-1). Subsequently, the VC was used as a packing material along with wood chips in proto-type bio-filters. Wood chips were mixed at 5-15% to form three distinct gradients in a test bio-filter. Under the three different CH4 loading rates of 33, 44 and 55 gCH4 m(-3)h(-1), the achieved MOPs were 31, 41, and 47gCH4 m(-3)h(-1), respectively. The gradient packed bed bio-filter is effective for landfill CH4 mitigation than the conventional bio-filter as the latter shows gas channeling effects with poor MOPs. PMID:26883060

  6. Implementation of Bin Packing Model for Reed Switch Production Planning

    SciTech Connect

    Parra, Rainier Romero

    2010-06-17

    This paper presents a form to resolve a real problem of efficient material election in reed switch manufacturing. The carrying out of the consumer demands depends on the stochastic results of the classification process where each lot of switches is distributed into bins according to an electric measure value. Various glass types are employed for the switch manufacturing. The effect caused by the glass type variation on the switch classification results was investigated. Based on real data statistic analysis, the problem is reduced to the lot number minimizing taking into consideration the glass type, and interpreted as a bin packing problem generalization. On difference to the classic bin packing problem, in the considered case, an item represents a set of pieces; a container is divided into a number of bins (sub-containers); the bin capacity is variable; there are the assignment restrictions between bins and sets of pieces; the items are allowed to be fragmented into bins and containers. The problem has a high complexity. A heuristic offline algorithm is proposed to find the quantity, types and packing sequence of containers, the item fragments associated with containers and bins. The bin capacities do not affect the algorithm.

  7. Assortative Mixing in Close-Packed Spatial Networks

    PubMed Central

    Turgut, Deniz; Atilgan, Ali Rana; Atilgan, Canan

    2010-01-01

    Background In recent years, there is aroused interest in expressing complex systems as networks of interacting nodes. Using descriptors from graph theory, it has been possible to classify many diverse systems derived from social and physical sciences alike. In particular, folded proteins as examples of self-assembled complex molecules have also been investigated intensely using these tools. However, we need to develop additional measures to classify different systems, in order to dissect the underlying hierarchy. Methodology and Principal Findings In this study, a general analytical relation for the dependence of nearest neighbor degree correlations on degree is derived. Dependence of local clustering on degree is shown to be the sole determining factor of assortative versus disassortative mixing in networks. The characteristics of networks constructed from spatial atomic/molecular systems exemplified by self-organized residue networks built from folded protein structures and block copolymers, atomic clusters and well-compressed polymeric melts are studied. Distributions of statistical properties of the networks are presented. For these densely-packed systems, assortative mixing in the network construction is found to apply, and conditions are derived for a simple linear dependence. Conclusions Our analyses (i) reveal patterns that are common to close-packed clusters of atoms/molecules, (ii) identify the type of surface effects prominent in different close-packed systems, and (iii) associate fingerprints that may be used to classify networks with varying types of correlations. PMID:21179578

  8. Pack cementation diffusion coatings for iron-base alloys

    SciTech Connect

    Rapp, R.A.

    1995-02-01

    With the aid of computer-assisted calculations of the equilibrium vapor pressures in halide-activated cementation packs, processing conditions have been identified and experimentally verified for the codeposition of two or more alloying elements in a diffusion coating on a variety of steels. The Cr-Si ferrite layers have proven to be very resistant to high temperature cyclic oxidation and to pitting in aqueous solutions. The process has been patented, and is being transferred for industrial application, e.g. for water walls of utility boilers, etc. In the proposed extension of this project, the use of mixed pure metal powders in the pack will be extended to achieve similar ferrite Fe-Cr-Al coatings with excellent oxidation resistance, with the eventual transfer of the technology to industry. In other recent studies, Ni-base alloy rods were aluminized by the halide-activated pack cementation process to bring their average composition to that for the ORNL-developed Ni{sub 3}Al, for use as a welding rod. A similar effort to develop a welding rod for the ORNL Fe{sub 3}Al alloy did not yield reproducible coating compositions or growth kinetics. The continued effort to produce Duriron-type (Fe-18Si-5Cr) coatings on steels was not successful. Literature for the intrinsic diffusion coefficients suggests that this task cannot be achieved.

  9. Influence of Crystal Packing on Global Protein Conformation

    NASA Astrophysics Data System (ADS)

    Ahlstrom, Logan; Miyashita, Osamu

    2011-10-01

    X-ray crystallography is the most robust method for solving protein structure. However, packing forces in the crystal lattice select just a snapshot of a protein's conformational ensemble, whereas proteins are flexible and can adopt different conformations. Here we compare molecular dynamics (MD) simulations in solution and the crystal lattice to add dynamical insight to the static X-ray images of proteins. As a model system, we consider the λ Cro dimer, whose solved X-ray structures range from a ``closed'' to an ``open'' global conformation. Free energy profiles depicting the conformational space sampled by the dimer in solution show some reported structures correspond to stable states. Yet other conformations, while accessible, lie higher in energy, indicating the effect of crystal packing. Subsequent crystal MD simulations estimated the strength of packing interfaces in the lattice, showing the influence of crystal form and mutation in stabilizing different dimer conformations. Our quantitative results will aid analysis of X-ray data in establishing protein structure-function relationships.

  10. Packing fraction of particles with a Weibull size distribution

    NASA Astrophysics Data System (ADS)

    Brouwers, H. J. H.

    2016-07-01

    This paper addresses the void fraction of polydisperse particles with a Weibull (or Rosin-Rammler) size distribution. It is demonstrated that the governing parameters of this distribution can be uniquely related to those of the lognormal distribution. Hence, an existing closed-form expression that predicts the void fraction of particles with a lognormal size distribution can be transformed into an expression for Weibull distributions. Both expressions contain the contraction coefficient β. Likewise the monosized void fraction φ1, it is a physical parameter which depends on the particles' shape and their state of compaction only. Based on a consideration of the scaled binary void contraction, a linear relation for (1 - φ1)β as function of φ1 is proposed, with proportionality constant B, depending on the state of compaction only. This is validated using computational and experimental packing data concerning random close and random loose packing arrangements. Finally, using this β, the closed-form analytical expression governing the void fraction of Weibull distributions is thoroughly compared with empirical data reported in the literature, and good agreement is found. Furthermore, the present analysis yields an algebraic equation relating the void fraction of monosized particles at different compaction states. This expression appears to be in good agreement with a broad collection of random close and random loose packing data.

  11. Pack hunting by a common soil amoeba on nematodes.

    PubMed

    Geisen, Stefan; Rosengarten, Jamila; Koller, Robert; Mulder, Christian; Urich, Tim; Bonkowski, Michael

    2015-11-01

    Soils host the most complex communities on Earth, including the most diverse and abundant eukaryotes, i.e. heterotrophic protists. Protists are generally considered as bacterivores, but evidence for negative interactions with nematodes both from laboratory and field studies exist. However, direct impacts of protists on nematodes remain unknown. We isolated the soil-borne testate amoeba Cryptodifflugia operculata and found a highly specialized and effective pack-hunting strategy to prey on bacterivorous nematodes. Enhanced reproduction in presence of prey nematodes suggests a beneficial predatory life history of these omnivorous soil amoebae. Cryptodifflugia operculata appears to selectively impact the nematode community composition as reductions of nematode numbers were species specific. Furthermore, we investigated 12 soil metatranscriptomes from five distinct locations throughout Europe for 18S ribosomal RNA transcripts of C. operculata. The presence of C. operculata transcripts in all samples, representing up to 4% of the active protist community, indicates a potential ecological importance of nematophagy performed by C. operculata in soil food webs. The unique pack-hunting strategy on nematodes that was previously unknown from protists, together with molecular evidence that these pack hunters are likely to be abundant and widespread in soils, imply a considerable importance of the hitherto neglected trophic link 'nematophagous protists' in soil food webs. PMID:26079718

  12. Comparison between bridges and force-chains in granular packings

    NASA Astrophysics Data System (ADS)

    Zhang, Ling; Cai, Shuxiao; Hu, Zunpeng; Zhang, Jie

    2013-03-01

    In dense granular materials, there exist chain-like force networks from which we can obtain much information on the mechanical properties of packings. But it is extremely difficult to characterize these structures, especially in 3D packings. Mehta and her coauthors have proposed theoretically that bridge-like structures can form because of spatial inhomogeneity and large fluctuations, and they conjecture that these mesoscopic geometric structures play the role of force-chains (Mehta et. al. 2004, Pugnaloni et. al. 2001). Some statistical features of bridges have been observed in a recent paper by Mattew C. Jenkins et al (Jenkins et. al. 2011). Despite the success, the lack of independent force network information makes the justification of Mehta et al.'s theoretical conjecture inconclusive. In this study, we focus on the comparison of bridges and force-chains in two different granular packing using photo-elastic granular particles. We have found no clear evidence that there exists a one-to-one mapping between bridges and force-chains. Nonetheless, for systems of different force chain structures, it does seem to show some differences in the respective bridge structures. This seems to suggest that some connection may exist between bridges and force-chains. We acknowledge the hospitality of the Duke University and the Los Alamos National Laboratory where the experiments were performed. JZ thanks the startup fund from SJTU and China 1000-plan-C.

  13. The structure of tropical forests and sphere packings.

    PubMed

    Taubert, Franziska; Jahn, Markus Wilhelm; Dobner, Hans-Jürgen; Wiegand, Thorsten; Huth, Andreas

    2015-12-01

    The search for simple principles underlying the complex architecture of ecological communities such as forests still challenges ecological theorists. We use tree diameter distributions--fundamental for deriving other forest attributes--to describe the structure of tropical forests. Here we argue that tree diameter distributions of natural tropical forests can be explained by stochastic packing of tree crowns representing a forest crown packing system: a method usually used in physics or chemistry. We demonstrate that tree diameter distributions emerge accurately from a surprisingly simple set of principles that include site-specific tree allometries, random placement of trees, competition for space, and mortality. The simple static model also successfully predicted the canopy structure, revealing that most trees in our two studied forests grow up to 30-50 m in height and that the highest packing density of about 60% is reached between the 25- and 40-m height layer. Our approach is an important step toward identifying a minimal set of processes responsible for generating the spatial structure of tropical forests. PMID:26598678

  14. Biofiltration of isopentane in peat and compost packed beds

    SciTech Connect

    Wang, Z.; Govind, R.

    1997-05-01

    Commercially available biofiltration systems have used natural bioactive materials in packed beds due to low media cost and easy availability. Detailed understanding and modeling of biofiltration systems are lacking in existing literature. Experimental studies on the isopentane treatment in air using peat- and compost-packed beds were conducted with inlet isopentane concentrations of 360 to 960 ppmv, and empty-bed gas-phase residence times of 2 to 10 min. High removal efficiencies (>90%) were achieved at low contaminant concentrations (<500 ppmv) and large empty-bed gas-phase residence times (>8 min). For both peat and compost biofilters, there was an optimal water content that gave the highest removal efficiency. For higher water content, mass transfer of isopentane through the liquid phase controlled the biofiltration removal efficiency. At low water content, irreversible changes in the bioactivity of peat and compost occurred, resulting in an irrecoverable loss of removal efficiency. Increases in biofilter bed temperature from 25 to 40 C improved the removal efficiency. A mathematical model incorporating the effect of water content and temperature was developed to describe the packed-bed biofilter performance. Model predictions agreed closely with experimental data.

  15. Packing fraction of particles with a Weibull size distribution.

    PubMed

    Brouwers, H J H

    2016-07-01

    This paper addresses the void fraction of polydisperse particles with a Weibull (or Rosin-Rammler) size distribution. It is demonstrated that the governing parameters of this distribution can be uniquely related to those of the lognormal distribution. Hence, an existing closed-form expression that predicts the void fraction of particles with a lognormal size distribution can be transformed into an expression for Weibull distributions. Both expressions contain the contraction coefficient β. Likewise the monosized void fraction φ_{1}, it is a physical parameter which depends on the particles' shape and their state of compaction only. Based on a consideration of the scaled binary void contraction, a linear relation for (1-φ_{1})β as function of φ_{1} is proposed, with proportionality constant B, depending on the state of compaction only. This is validated using computational and experimental packing data concerning random close and random loose packing arrangements. Finally, using this β, the closed-form analytical expression governing the void fraction of Weibull distributions is thoroughly compared with empirical data reported in the literature, and good agreement is found. Furthermore, the present analysis yields an algebraic equation relating the void fraction of monosized particles at different compaction states. This expression appears to be in good agreement with a broad collection of random close and random loose packing data. PMID:27575204

  16. Viscosities and sintering rates of composite packings of spheres

    SciTech Connect

    Jagota, A.; Scherer, G.W.

    1995-03-01

    The effective sintering rates and viscosities of three-dimensional composite packings have been studied using a discrete numerical model. The packings consist of random mixtures of hard and soft spheres of the same size. With increasing substitution of hard particles for soft particles in the packing, the viscosity increases and the sintering rate decreases. This is particularly abrupt at well-defined rigidity thresholds where there is a transition from softlike to hardlike behavior. The site fraction of hard particles at which the transition occurs depends on the nature of the interaction between hard particles. When the contact between hard particles resists all six relative degrees of freedom (relative velocities and spins). the bonded case, the rigidity threshold coincides with the percolation threshold (site fraction {approx}0.32). When the contact between hard particles resists only interpenetration. the sliding case, the threshold occurs at a site fraction of hard particles very close to unity. Results for the variation of effective properties with site fraction of hard particles are presented for these and other cases. These results can also be applied to the study of elastic percolating networks.

  17. Side-chain entropy and packing in proteins.

    PubMed

    Bromberg, S; Dill, K A

    1994-07-01

    What role does side-chain packing play in protein stability and structure? To address this question, we compare a lattice model with side chains (SCM) to a linear lattice model without side chains (LCM). Self-avoiding configurations are enumerated in 2 and 3 dimensions exhaustively for short chains and by Monte Carlo sampling for chains up to 50 main-chain monomers long. This comparison shows that (1) side-chain degrees of freedom increase the entropy of open conformations, but side-chain steric exclusion decreases the entropy of compact conformations, thus producing a substantial entropy that opposes folding; (2) there is side-chain "freezing" or ordering, i.e., a sharp decrease in entropy, near maximum compactness; and (3) the different types of contacts among side chains (s) and main-chain elements (m) have different frequencies, and the frequencies have different dependencies on compactness. mm contacts contribute significantly only at high densities, suggesting that main-chain hydrogen bonding in proteins may be promoted by compactness. The distributions of mm, ms, and ss contacts in compact SCM configurations are similar to the distributions in protein structures in the Brookhaven Protein Data Bank. We propose that packing in proteins is more like the packing of nuts and bolts in a jar than like the pairwise matching of jigsaw puzzle pieces. PMID:7920265

  18. The structure of tropical forests and sphere packings

    PubMed Central

    Jahn, Markus Wilhelm; Dobner, Hans-Jürgen; Wiegand, Thorsten; Huth, Andreas

    2015-01-01

    The search for simple principles underlying the complex architecture of ecological communities such as forests still challenges ecological theorists. We use tree diameter distributions—fundamental for deriving other forest attributes—to describe the structure of tropical forests. Here we argue that tree diameter distributions of natural tropical forests can be explained by stochastic packing of tree crowns representing a forest crown packing system: a method usually used in physics or chemistry. We demonstrate that tree diameter distributions emerge accurately from a surprisingly simple set of principles that include site-specific tree allometries, random placement of trees, competition for space, and mortality. The simple static model also successfully predicted the canopy structure, revealing that most trees in our two studied forests grow up to 30–50 m in height and that the highest packing density of about 60% is reached between the 25- and 40-m height layer. Our approach is an important step toward identifying a minimal set of processes responsible for generating the spatial structure of tropical forests. PMID:26598678

  19. Dielectric Properties of Close-Packed Disordered Suspensions

    NASA Astrophysics Data System (ADS)

    Davis, Victoria Ann

    Multiple scattering techniques are used to calculate the dielectric properties of composites, specifically, close-packed disordered suspensions. Composites are usually described using single-site, long-wavelength approximations which are not applicable for either close-packed or disordered systems. In a suspension, the dielectric properties can be described in terms of electromagnetic waves multiply scattered from the inclusions and, therefore, we can use the power of Multiple-Scattering Theory together with Roth's Effective-Medium Approximation (EMA). The EMA goes beyond previous approximations as it includes particle size effects and local field fluctuations. We apply the EMA to two types of suspensions: (1) strong scattering systems of metal spheres embedded in insulating hosts and (2) a weak scattering system of pressed Al(,2)O(,3) particles. The EMA reproduces the basic features of the relevant experimental results better than other approximations. In order to further explore the utility of the EMA, we examine a model system of a Drude metal in an insulating host. The trends observed in the EMA results are those expected for a close -packed composite on the basis of general theoretical arguments.

  20. Visualization of Flows in Packed Beds of Twisted Tapes

    NASA Technical Reports Server (NTRS)

    Hendricks, R. C.; Braun, M. J.; Peloso, D.; Athavale, M. M.; Mullen, R. L.

    2002-01-01

    A videotape presentation of the flow field in a packed bed of 48 twisted tapes which can be simulated by very thin virtual cylinders has been assembled. The indices of refraction of the oil and the Lucite twisted tapes were closely matched, and the flow was seeded with magnesium oxide particles. Planar laser light projected the flow field in two dimensions both along and transverse to the flow axis. The flow field was three dimensional and complex to describe, yet the most prominent finding was flow threads. It appeared that axial flow spiraled along either within the confines of a virtual cylindrical boundary or within the exterior region, between the tangency points, of the virtual cylinders. Random packing and bed voids created vortices and disrupted the laminar flow but minimized the entrance effects. The flow-pressure drops in the packed bed fell below the Ergun model for porous-media flows. Single-twisted-tape results of Smithberg and Landis (1964) were used to guide the analysis. In appendix A the results of several investigators are scaled to the Ergun model. Further investigations including different geometric configurations, computational fluid dynamic (CFD) gridding, and analysis are required.