WorldWideScience
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Influenza Vaccines  

International Science & Technology Center (ISTC)

Development of the Culture Influenza Vaccine

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Reversing B cell aging  

UK PubMed Central (United Kingdom)

Age-related alterations in the cellular composition of the B lineage are a major cause of the poor antibody response to vaccination and to infectious agents among the elderly population. The mechanisms...Full Text Available

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International Atomic Energy Agency publications. Publications catalogue 2006 including full details of publications published in 2004-2005 and forthcoming in 2006 and a stocklist of publications published in 2002-2003  

International Nuclear Information System (INIS)

This Publications Catalogue lists all sales publications of the IAEA published in 2004, 2005 and forthcoming in 2006. Most IAEA publications are issued in English, some are also available in Arabic, Chinese, French, Russian or Spanish. This is indicated at the bottom of the book entry. A complete listing of all IAEA priced publications is available on the IAEA's web site: http://www.iaea.org/books

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Influenza  

Medline Plus

... a flu shot There is a new nasal spray version of the vaccine, and it contains weakened ... the LAIV (Live Attenuated Influenza Vaccine). The nasal-spray flu vaccine contains three different live but weakened ...

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CDC - Seasonal Influenza (Flu) - Q & A: 2007-08 Influenza (Flu...  

Science.gov (United States)

home when you are sick helps everyone you care about Questions & Answers Flu Vaccine: Q&A Vaccine Dosage & Administration Vaccine Supply for 2011-12 Season Vaccine Supply and...

2011-10-15

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CDC - Seasonal Influenza (Flu) - Q & A: 2006-07 Influenza (Flu...  

Science.gov (United States)

home when you are sick helps everyone you care about Questions & Answers Flu Vaccine: Q&A Vaccine Dosage & Administration Vaccine Supply for 2011-12 Season Vaccine Supply and...

2011-10-15

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CDC - Seasonal Influenza (Flu) - Q & A about the 2010-2011 Flu...  

Science.gov (United States)

home when you are sick helps everyone you care about Questions & Answers Flu Vaccine: Q&A Vaccine Dosage & Administration Vaccine Supply for 2011-12 Season Vaccine Supply and...

2011-10-15

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Response to measles-mumps-rubella vaccine in children on dialysis.  

Science.gov (United States)

Ten children receiving maintenance dialysis were immunized with the standard dose of measles-mumps-rubella vaccine between 15 and 33 months of age. Immune responses to vaccination were determined using commercially available enzyme-linked immunosorbent assays for measles, mumps, and rubella viruses. Eight children responded to measles vaccine, 5 to mumps vaccine, 8 to rubella vaccine, and only 3 children to all three vaccines, compared with a seroconversion rate of over 90% to all three vaccines in healthy children (P less than 0.0001). We contend that the relatively poor immunocompetence of our dialysis patients explains their less than optimal vaccine response and suggest that children vaccinated while undergoing dialysis be tested to confirm serological evidence of immunity. PMID:1571219

1992-03-01

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Advances in molecular biology: impact on rotavirus vaccine development.  

Science.gov (United States)

The first candidate rotavirus vaccine was a live attenuated oral vaccine made by the classical empirical method of serial passage of virus in tissue culture cells. Current tetravalent vaccine candidates that are in the final stages of efficacy testing in the United States were made by genetic reassortment. This article briefly highlights how advances in the basic understanding of the molecular biology of rotaviruses have facilitated vaccine development. New approaches for second-generation vaccines and improvements in vaccine efficacy based on further exploitation of the tools and knowledge of rotavirus molecular biology and pathogenesis are discussed. PMID:8752289

1996-09-01

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Geothermal studies of the Outokumpu Deep Drill Hole, Finland: Vertical variation in heat flow and palaeoclimatic implications  

British Library Electronic Table of Contents (United Kingdom)

Detailed geothermal studies of deep drill holes provide insights to heat transfer processes in the crust, and allow separation of different factors involved, such as palaeoclimatic and structural conductive effects as well as advective fluid flow effects. We present high resolution geothermal results of the 2516m deep Outokumpu Deep Drill Hole in eastern Finland drilled in 2004-2005 into a Palaeoproterozoic formation with metasedimentary rocks, ophiolite-derived altered ultramafic rocks and pegmatitic granite. The down-hole temperatures have been logged five times after end of drilling and extend to day 948 after drilling. The hole is completely cored (79% core coverage) and thermal conductivity measurements were done at 1m intervals. The geothermal results on temperature gradient, thermal...

2011-01-01

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Challenges to wheat production in South Asia  

British Library Electronic Table of Contents (United Kingdom)

Wheat is the second major staple crop, after rice, in India and Pakistan and is also gaining similar importance in Nepal and Bangladesh. Wheat production in South Asia has increased from 15?mt in 1960s to 95.5?mt during 2004?2005. It still needs to grow at the rate of 2?2.5% annually until the middle of 21st century. However, for India, recent estimations have shown a growth requirement of about 1.1%. Although the wheat improvement programs in these countries, with the active collaboration of national agricultural research centers (NARS) and CIMMYT, has made a significant progress, it is a matter of significant concern that wheat production has stagnated for last few years. Since there is little scope for increasing land area under wheat, the major challenge will be to break the yield barr...

2007-01-01

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Building drought management capacity in the Mekong River basin  

British Library Electronic Table of Contents (United Kingdom)

Over the past decades the Mekong River basin has experienced several droughts, the most recent of which occurred in the hydrological year 2004/2005. Impacts extended across agriculture, forestry, water resources, supply, industry, transport and the environment. In early 2006, the Mekong River Commission Secretariat initiated close consultations with the MRC member states Cambodia, Lao PDR, Thailand and Vietnam, aiming at the formulation of a common Drought Management Programme, which would enhance the existing drought management capacity and ensure effective support. This paper draws attention to the programme formulation process. It shows how national capacity needs were assessed and synthesized into a basin-wide capacity development programme. The paper concludes that in the context of i...

2008-01-01

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Safety and immunogenicity of a vaccine bait containing ERA strain of attenuated rabies virus.  

UK PubMed Central (United Kingdom)

Ninety percent of foxes fed commercial ERA vaccine in a specially designed bait developed rabies serum neutralizing antibodies. The vaccine bait did not cause clinical signs of rabies when consumed...Full Text Available

1987-10-01

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Population-based prevention of influenza in Dutch general practice.  

UK PubMed Central (United Kingdom)

BACKGROUND: Although the effectiveness of influenza vaccination in high-risk groups has been proven, vaccine coverage continues to be less than 50% in The Netherlands. To improve vaccination rates,...Full Text Available

1997-06-01

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Novel Approach for Differential Diagnosis of HIV Infections in the Face of Vaccine-Generated Antibodies  

UK PubMed Central (United Kingdom)

SummaryBecause increasing numbers of HIV vaccine candidates are being tested globally, it is essential to differentiate vaccine-from virus-induced antibodies. Most of the currently...Full Text Available

2006-11-01

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Contrasting Population Structures of the Genes Encoding Ten Leading Vaccine-Candidate Antigens of the Human Malaria Parasite, Plasmodium falciparum  

UK PubMed Central (United Kingdom)

The extensive diversity of Plasmodium falciparum antigens is a major obstacle to a broadly effective malaria vaccine but population genetics has rarely been used to guide vaccine design....Full Text Available

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A semi-qualitative study of attitudes to vaccinating adolescents against human papillomavirus without parental consent  

UK PubMed Central (United Kingdom)

BackgroundThe first vaccine to prevent human papillomavirus (HPV) and cervical cancer has been licensed, and in future, vaccination may be routinely offered to 10–14 year...Full Text Available

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Methanogen community structure in the rumens of farmed sheep, cattle and red deer fed different diets  

British Library Electronic Table of Contents (United Kingdom)

Abstract Development of inhibitors and vaccines that mitigate rumen-derived methane by targeting methanogens relies on knowledge of the methanogens present. We investigated the composition of archaeal communities in the rumens of farmed sheep (Ovis aries), cattle (Bos taurus) and red deer (Cervus elaphus) using denaturing gradient gel electrophoresis (DGGE) to generate fingerprints of archaeal 16S rRNA genes. The total archaeal communities were relatively constant across species and diets, and were less variable and less diverse than bacterial communities. There were diet- and ruminant-species-based differences in archaeal community structure, but the same dominant archaea were present in all rumens. These were members of three coherent clades: species related to Methanobrevibacter ruminan...

2011-01-01

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Isolation and Identification of Mycoplasmas  

International Science & Technology Center (ISTC)

Isolation and Identification of Mycoplasmas, Development of Reliable Antigen for Mycoplasmas Detection and Oil-Based Vaccines

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Weed control and wheat (Triticum aestivum L.) yield under application of 2,4-D plus carfentrazone-ethyl and florasulam plus flumetsulam: Evaluation of the efficacy  

British Library Electronic Table of Contents (United Kingdom)

Three field experiments were conducted at the research fields of Plant Protection Research Institute, Iran, at different locations in 2004-2005 to study the efficacy of different broadleaved herbicides to control weeds in wheat. Treatments were the full-season hand weeded and weed-infested controls, and post-emergence applications of florasulam plus flumetsulam at 8.75, 10.50, and 12.25ga.i./ha, 2,4-D plus carfentrazone-ethyl at 210, 245, 280, and 490ga.i./ha, bromoxynil plus MCPA at 75, 100, and 150ga.i./ha, 2,4-D at 560, 720, and 1120ga.i./ha, tribenuron methyl, and 2,4-D plus MCPA. Herbicides were applied at wheat tillering stage. Naturally occurring broadleaved weed populations were used in experiments. Results indicated that bromoxynil plus MCPA at 150ga.i./ha, 2,4-D plus MCPA, and 2,...

2007-01-01

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The influence of MHC polymorphism on the selection of T-cell determinants of FMDV in cattle.  

UK PubMed Central (United Kingdom)

There is a quest for the development of a new generation of vaccines consisting of well-defined subunit antigens. For a number of practical reasons it is attractive to develop vaccines on the basis...Full Text Available

1995-01-01

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Tat-Neutralizing Antibodies in Vaccinated Macaques  

UK PubMed Central (United Kingdom)

The human immunodeficiency virus Tat protein is essential for virus replication and is a candidate vaccine antigen. Macaques immunized with Tat or chemically modified Tat toxoid having the same clade...Full Text Available

2003-03-01

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Synchronous infection of SIV and HIV in vitro for virology, immunology, and vaccine-related studies  

UK PubMed Central (United Kingdom)

The development of an HIV vaccine will require a more precise understanding of the immunological and virological underpinnings of HIV infection. Magnetofection, the process of magnetizing HIV...Full Text Available

2010-01-01

27

Safety and Immunogenicity of Novel Recombinant BCG and Modified Vaccinia Virus Ankara Vaccines in Neonate Rhesus Macaques ?  

UK PubMed Central (United Kingdom)

Although major inroads into making antiretroviral therapy available in resource-poor countries have been made, there is an urgent need for an effective vaccine administered shortly after birth, which...Full Text Available

2010-08-01

28

Pathway to Licensure for Protective Antigen-based Anthrax Vaccines ...  

Science.gov (United States)

... Weiss, S., D. Kobiler, H. Levy, H. Marcus, A. Pass, N. Rothschild, and Z ... of Bacillus anthracis spores conferred by a protective antigen-based vaccine in rabbits ...

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Mothers' concept of measles and attitudes towards the measles vaccine in Ile-Ife, Nigeria.  

UK PubMed Central (United Kingdom)

The attitude of Nigerian mothers, mainly Yoruba, towards measles vaccine and other aspects of prevention are influenced by different perceptions of the cause of measles. There is a significant correlation...Full Text Available

1982-09-01

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Molecular characterization of a Chinese variant of the Flury-LEP strain  

UK PubMed Central (United Kingdom)

The entire genome of rabies virus vaccine strain Flury-LEP-C, a Chinese variant of the rabies virus vaccine strain Flury-LEP, was sequenced. The overall length of the genome of Flury-LEP-C strain was...Full Text Available

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Indian vaccine innovation: the case of Shantha Biotechnics  

UK PubMed Central (United Kingdom)

BackgroundAlthough the World Health Organization had recommended that every child be vaccinated for Hepatitis B by the early 1980s, large multinational pharmaceutical companies held...Full Text Available

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Cryoglobinaemia in rabbits hyperimmunized with a polyvalent pneumococcal vaccine  

UK PubMed Central (United Kingdom)

During the anamnestic response, the sera of four rabbits immunized with a polyvalent pneumococcal vaccine contained large amounts of cryoglobulins belonging to the G and M immunoglobulin classes. These...Full Text Available

1965-10-01

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Correlates to Increased Lethality of Attenuated Venezuelan Encephalitis Virus Vaccine for Immunosuppressed Hamsters.  

Science.gov (United States)

Splenectomy or pretreatment of adult hamsters with cyclophosphamide (Cytoxan) increased the lethality of the TC-83 vaccine strain of Venezuelan encephalitis virus (VEE), inoculated subcutaneously, from 12% for normal hamsters to 75 and 76% respectively. A...

1974-01-01

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A viral vaccine encoding PSA induces antigen spreading to a common set of self proteins in prostate cancer patients  

UK PubMed Central (United Kingdom)

PurposeWe previously reported a randomized phase II clinical trial combining a poxvirus-based vaccine encoding PSA with radiotherapy in patients with localized prostate...Full Text Available

2010-08-01

35

Vaccination response to tetanus toxoid and 23-valent pneumococcal vaccines following administration of a single dose of abatacept: a randomized, open-label, parallel group study in healthy subjects  

UK PubMed Central (United Kingdom)

The effect of abatacept, a selective T-cell co-stimulation modulator, on vaccination has not been previously investigated. In this open-label, single-dose, randomized, parallel-group, controlled study,...Full Text Available

2007-01-01

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Long-Term Specific Immune Responses Induced in Humans by a Human Immunodeficiency Virus Type 1 Lipopeptide Vaccine: Characterization of CD8+-T-Cell Epitopes Recognized  

UK PubMed Central (United Kingdom)

We studied the effect of booster injections and the long-term immune response after injections of an anti-human immunodeficiency virus type 1 (HIV-1) lipopeptide vaccine. This vaccine was injected alone...Full Text Available

2003-10-01

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Comparison of a multivalent viral vaccine program versus a univalent viral vaccine program on animal health, feedlot performance, and carcass characteristics of feedlot calves  

UK PubMed Central (United Kingdom)

A field study was conducted under commercial feedlot conditions at 2 sites in western Canada to determine the relative effects of a univalent viral vaccine (MLV 1) program versus a multivalent viral...Full Text Available

2003-01-01

38

The immunological era in melanoma treatment: new challenges for heat shock protein-based vaccine in the advanced disease  

British Library Electronic Table of Contents (United Kingdom)

Introduction: Tumor-derived heat shock protein (HSP)-peptide complexes (HSPPCs) induced immunity against malignancies in preclinical trials, working across tumor types and bypassing the need to identify single immunogenic peptides. These results paved the way for the use of human gp96 obtained from autologous tumor samples as an anti-cancer vaccine. Areas covered: Autologous tumor-derived HSP gp96 peptide complex (HSPPC-96) vaccine is emerging as a tumor- and patient-specific cancer vaccine, with confirmed activity in several malignancies. It has been tested in Phase III clinical trials in advanced melanoma and kidney cancer with evidence for efficacy in patients with earlier stage disease. HSPPC-96-based vaccine demonstrated an excellent safety profile, thus emerging as a novel therapeuti...

2011-01-01

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Current status of a hepatitis C vaccine: encouraging results but significant challenges ahead  

DEFF Research Database (Denmark)

Persistent hepatitis C virus (HCV) infection affects 170 million people worldwide. Acute HCV infection is often asymptomatic, but many infected individuals develop persistent infections that may lead to development of end-stage liver diseases, including liver cirrhosis and hepatocellular carcinoma. Thus, an HCV vaccine that could significantly lower the chronicity rate would have a major impact on the disease burden. Unfortunately, HCV is a highly mutable virus, and escape mutations can undermine vaccine-induced virus-specific immunity. Also, HCV exists as multiple genotypes, and so genotype-specific vaccines might be required to achieve broad protection. Finally, vaccine development has been hampered by the lack of a small animal model and cell culture systems, but these are currently being established. Despite these obstacles, several vaccine candidates tested in the chimpanzee ...

2007-01-01

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The Case for Reactive Mass Oral Cholera Vaccinations  

UK PubMed Central (United Kingdom)

IntroductionThe outbreak of cholera in Zimbabwe intensified interest in the control and prevention of cholera. While there is agreement that safe water, sanitation, and personal...Full Text Available

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Reporting Problems to FDA  

Medline Plus

Enter Search terms A-Z Index Home Food Drugs Medical Devices Vaccines, Blood & Biologics Animal & Veterinary Cosmetics Radiation-Emitting Products Tobacco ...

42

Health Information for Travelers to South Africa - Travelers...  

Science.gov (United States)

more information about this message, please visit this page: About CDC.gov. Travelers' Health Home Destinations (238) South Africa Regions Vaccinations News & Announcements Travel...

2011-08-28

43

Health Information for Travelers to Somalia - Travelers' Health...  

Science.gov (United States)

more information about this message, please visit this page: About CDC.gov. Travelers' Health Home Destinations (238) Somalia Regions Vaccinations News & Announcements Travel...

2011-08-28

44

Health Information for Travelers to Saudi Arabia - Travelers...  

Science.gov (United States)

more information about this message, please visit this page: About CDC.gov. Travelers' Health Home Destinations (238) Saudi Arabia Regions Vaccinations News & Announcements Travel...

2011-08-28

45

Health Information for Travelers to Rwanda - Travelers' Health...  

Science.gov (United States)

more information about this message, please visit this page: About CDC.gov. Travelers' Health Home Destinations (238) Rwanda Regions Vaccinations News & Announcements Travel...

2011-08-28

46

Health Information for Travelers to Mozambique - Travelers' Health...  

Science.gov (United States)

more information about this message, please visit this page: About CDC.gov. Travelers' Health Home Destinations (238) Mozambique Regions Vaccinations News & Announcements Travel...

2011-08-28

47

Health Information for Travelers to Malawi - Travelers' Health...  

Science.gov (United States)

more information about this message, please visit this page: About CDC.gov. Travelers' Health Home Destinations (238) Malawi Regions Vaccinations News & Announcements Travel...

2011-08-28

48

Health Information for Travelers to Kenya - Travelers' Health...  

Science.gov (United States)

more information about this message, please visit this page: About CDC.gov. Travelers' Health Home Destinations (238) Kenya Regions Vaccinations News & Announcements Travel Notices...

2011-08-28

49

Health Information for Travelers to Iran - Travelers' Health...  

Science.gov (United States)

please visit this page: About CDC.gov. Travelers' Health Home Destinations (238) Iran Regions Vaccinations News & Announcements Travel Notices Diseases Yellow Book Contents...

2011-09-04

50

Health Information for Travelers to Gabon - Travelers' Health...  

Science.gov (United States)

more information about this message, please visit this page: About CDC.gov. Travelers' Health Home Destinations (238) Gabon Regions Vaccinations News & Announcements Travel Notices...

2011-08-28

51

Health Information for Travelers to Ethiopia - Travelers' Health...  

Science.gov (United States)

more information about this message, please visit this page: About CDC.gov. Travelers' Health Home Destinations (238) Ethiopia Regions Vaccinations News & Announcements Travel...

2011-08-28

52

Health Information for Travelers to Eritrea - Travelers' Health...  

Science.gov (United States)

more information about this message, please visit this page: About CDC.gov. Travelers' Health Home Destinations (238) Eritrea Regions Vaccinations News & Announcements Travel...

2011-08-28

53

Health Information for Travelers to Equatorial Guinea - Travelers...  

Science.gov (United States)

more information about this message, please visit this page: About CDC.gov. Travelers' Health Home Destinations (238) Equatorial Guinea Regions Vaccinations News & Announcements...

2011-08-28

54

Health Information for Travelers to Djibouti - Travelers' Health...  

Science.gov (United States)

more information about this message, please visit this page: About CDC.gov. Travelers' Health Home Destinations (238) Djibouti Regions Vaccinations News & Announcements Travel...

2011-08-28

55

Health Information for Travelers to Democratic Republic of the...  

Science.gov (United States)

more information about this message, please visit this page: About CDC.gov. Travelers' Health Home Destinations (238) Democratic Republic of the Congo Regions Vaccinations News &...

2011-08-28

56

Health Information for Travelers to Antarctica - Travelers' Health...  

Science.gov (United States)

more information about this message, please visit this page: About CDC.gov. Travelers' Health Home Destinations (238) Antarctica Regions Vaccinations News & Announcements Travel...

2011-08-28

57

Diphtheria in Europe.  

UK PubMed Central (United Kingdom)

A letter of inquiry was sent to 21 countries in Europe to ascertain their experience of diphtheria during the last 20 years. An analysis of the 15 replies showed that all relied on childhood vaccination...Full Text Available

1984-12-01

58

Controlling Endemic Cholera with Oral Vaccines  

UK PubMed Central (United Kingdom)

BackgroundAlthough advances in rehydration therapy have made cholera a treatable disease with low case-fatality in settings with appropriate medical care, cholera continues...Full Text Available

2007-11-01

59

Bioterrorism and Biocrimes: The Illicit Use of Biological Agents ...  

Science.gov (United States)

... view on the utility of such attacks, see JH Rothschild, Tomorrow's Weapons ... Aum Shinrikyo may have had a stolen vaccine anthrax strain incapable ...

2001-02-01

60

A multifactorial strategy of pain management is associated with less pain in scheduled vaccination of children. A study realized by family practitioners in 239 children aged 4-12 years old  

British Library Electronic Table of Contents (United Kingdom)

Background and aims. The multiplicity of vaccine injections during childhood leads to iterative painful and stressful experiences which may lead in turn to anticipated pain and then possibly to a true needle phobia. We aimed at evaluating a multifactorial strategy of pain management combining pharmacological and non-pharmacological approaches during vaccination, as compared to usual care, in 4- to 12-year-old children. Methods. In all, 239 children were enroled by 25 family practitioners in an open-label study. After a pseudo-randomization, usual pain management (n = 132) was compared to a multifactorial strategy (n = 107) associating preliminary application of an anesthesic patch, preferential use of specified vaccines, child education by the parents and the doctor, parental accompaniment...

2008-01-01

61

A Novel Multi-Antigen Virally Vectored Vaccine against Mycobacterium avium Subspecies paratuberculosis  

UK PubMed Central (United Kingdom)

BackgroundMycobacterium avium subspecies paratuberculosis causes systemic infection and chronic intestinal inflammation in many species including...Full Text Available

62

T Cell Responses to the RTS,S/AS01E and RTS,S/AS02D Malaria Candidate Vaccines Administered According to Different Schedules to Ghanaian Children  

UK PubMed Central (United Kingdom)

BackgroundThe Plasmodium falciparum pre-erythrocytic stage candidate vaccine RTS,S is being developed for protection of young children against...Full Text Available

63

Preliminary Assessment of the Safety and Immunogenicity of a New CTX?-Negative, Hemagglutinin/Protease-Defective El Tor Strain as a Cholera Vaccine Candidate  

UK PubMed Central (United Kingdom)

Vibrio cholerae 638 (El Tor, Ogawa), a new CTXΦ-negative hemagglutinin/protease-defective strain that is a cholera vaccine candidate, was examined for safety and immunogenicity...Full Text Available

1999-02-01

64

Potent immune responses and in vitro pro-inflammatory cytokine suppression by a novel adenovirus vaccine vector based on rare human serotype 28  

UK PubMed Central (United Kingdom)

Adenovirus vaccine vectors derived from rare human serotypes have been shown to be less potent than serotype 5 (Ad5) at inducing immune responses to encoded antigens. To identify highly immunogenic...Full Text Available

2010-08-09

65

NAME=\\  

Wastenet

...INFORMATION Diarrhoeal disease Food safety and foodborne illness Enterohaemorrhagic Escherichia coli (EHEC) Cholera WHO PROGRAMMES AND ACTIVITIES Child and Adolescent Health and Development (...FOS) Initiative for Vaccine Research (IVR) TECHNICAL INFORMATION Vaccine research: diarrhoeal diseases Cholera Water-related diseases Household water treatment and safe storage WHO Global Salm-Surv ...PUBLICATIONS Diarrhoea: child and adolescent health Diarrhoea: cholera RELATED TOPICS - Child health - Water - Food safety - Cholera - Travel - Breastfeeding ...

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Molecular Characterization of a Haemaphysalis longicornis Tick Salivary Gland-Associated 29-Kilodalton Protein and Its Effect as a Vaccine against Tick Infestation in Rabbits  

UK PubMed Central (United Kingdom)

The use of tick vaccines in mammalian hosts has been shown to be the most promising alternative tick control method to current use of acaricides, which suffers from a number of limitations. However,...Full Text Available

1999-04-01

67

Efficacy of a heat inactivated hepatitis B vaccine in male homosexuals: outcome of a placebo controlled double blind trial.  

UK PubMed Central (United Kingdom)

The efficacy of a heat inactivated hepatitis B virus vaccine, containing 3 micrograms hepatitis B surface antigen (HBsAg), was studied in a high risk group of 800 susceptible homosexual men by a randomised...Full Text Available

1983-04-23

68

Effects of 2 commercially-available 9-way killed vaccines on milk production and rectal temperature in Holstein-Friesian dairy cows.  

UK PubMed Central (United Kingdom)

Veterinarians and farmers employing multivalent killed vaccines in lactating dairy cows have reported transient losses in milk production. Few studies have quantified this loss. In this report, effects...Full Text Available

2001-10-01

69

A recombinant Yellow Fever 17D vaccine expressing Lassa virus glycoproteins  

UK PubMed Central (United Kingdom)

The Yellow Fever Vaccine 17D (YFV17D) has been used as a vector for the Lassa virus glycoprotein precursor (LASV-GPC) resulting in construction of YFV17D/LASV-GPC recombinant virus. The virus...Full Text Available

2006-02-20

70

A Randomized Trial Assessing the Safety and Immunogenicity of AS01 and AS02 Adjuvanted RTS,S Malaria Vaccine Candidates in Children in Gabon  

UK PubMed Central (United Kingdom)

BackgroundThe malaria vaccine candidate antigen RTS,S includes parts of the pre-erythrocytic stage circumsporozoite protein fused to the Hepatitis B surface antigen. Two Adjuvant...Full Text Available

71

Reproductive Ecology of Yakima River Hatchery and Wild Spring Chinook; Yakima/Klickitat Fisheries Project Monitoring and Evaluation, 2004-2005 Annual Report.  

Energy Technology Data Exchange (ETDEWEB)

This report is intended to satisfy two concurrent needs: (1) provide a contract deliverable from Oncorh Consulting to the Washington Department of Fish and Wildlife (WDFW), with emphasis on identification of salient results of value to ongoing Yakima/Klickitat Fisheries Project (YKFP) planning and (2) summarize results of research that have broader scientific relevance. This is the fourth in a series of reports that address reproductive ecological research and monitoring of spring chinook populations in the Yakima River basin. This annual report summarizes data collected between April 1, 2004 and March 31, 2005 and includes analyses of historical baseline data, as well. Supplementation success in the Yakima Klickitat Fishery Project's (YKFP) spring chinook (Oncorhynchus tshawytscha) program is defined as increasing natural production and harvest opportunities, while keeping adverse ecological interactions and genetic impacts within acceptable bounds (Busack et al. 1997). ...

2005-05-01

72

Serological testing-An alternative to boosters?  

British Library Electronic Table of Contents (United Kingdom)

The issue of the duration of immunity, particularly for the modified live viral components of veterinary vaccines, has been a significant part of the recent vaccination debate. One manufacturer has increased the recommended booster interval for these components to 3 years give name and another now states `up to 4 years' immunity.There remain many unanswered questions regarding this duration of immunity (DOI). Studies suitable for data sheet claims are time consuming and costly and can only be performed in laboratory dogs under tightly controlled conditions. Evidence from rabies serology testing in the UK shows that the response of individual animals to routine vaccination is highly variable. Much of the published field evidence on the persistence of antibody titres originates from North Am...

2006-01-01

73

Immunogenicity, efficacy, safety and effectiveness of pneumococcal conjugate vaccines (1998-2006)  

British Library Electronic Table of Contents (United Kingdom)

In this paper we present an overview of the literature on efficacy and safety trials of the various pneumococcal conjugate vaccines on the market (PCV7) and in development (PCV9, PCV11 and allegedly PCV10 and PCV13), as well as of observations from post-licensure studies. Seven- (PCV7) and nine-valent PCV (PCV9) are reported to be sufficiently immunogenic after administration of a 3+1 schedule in infants in various RCTs. PncOMPC (PCV7 with a protein of N. meningitidis as a carrier) is less immunogenic, though this may have no repercussions for the protective efficacy against clinical disease. PCV7 is 82-97% efficacious against vaccine serotype (VT) IPD, 90% efficacious against (clinically diagnosed) pneumococcal pneumonia, and, like the 11-valent PCV, 57% efficacious against VT acute otiti...

2007-01-01

74

An oral nervous necrosis virus vaccine using Vibrio anguillarum as an expression host provides early protection  

British Library Electronic Table of Contents (United Kingdom)

Oral vaccination is the most desirable immunization method by which to prevent fish disease occurring at the early larval stage. We developed an Escherichia coli-based oral nervous necrosis virus (NNV) subunit vaccine and demonstrated its effectiveness in orange spotted grouper (Epinephelus coioides) fry. However, the incubation period was determined to be over 2weeks. To enhance the efficacy and shorten the incubation period, a safe and digestible biological adjuvant should be found. Vibrio anguillarum, a common marine bacterium with immune-stimulatory capability was selected as an expression host. An expression vector containing its heat shock protein 60 gene (groE) as an inducible promoter was constructed to express recombinant NNV coat protein as an antigen. The recombinant V. anguilla...

2011-01-01

75

Therapeutic Vaccination in Chronic Hepatitis B: Preclinical Studies in the Woodchuck  

UK PubMed Central (United Kingdom)

Recommended treatment of chronic hepatitis B with interferon-α and/or nucleos(t)ide analogues does not lead to a satisfactory result. Induction of HBV-specific T cells by therapeutic...Full Text Available

2010-01-01

76

The hemoglobins of the trematodes Fasciola hepatica and Paramphistomum epiclitum: A molecular biological, physico-chemical, kinetic, and vaccination study  

UK PubMed Central (United Kingdom)

The trematode Fasciola hepatica (Fa.he.) is a common parasite of human and livestock. The hemoglobin (Hb) of Fa.he., a potential immunogen, was chosen for characterization...Full Text Available

2008-10-01

77

Testing the Efficacy of a Multi-Component DNA-Prime/DNA-Boost Vaccine against Trypanosoma cruzi Infection in Dogs  

UK PubMed Central (United Kingdom)

BackgroundTrypanosoma cruzi, the etiologic agent of Chagas Disease, is a major vector borne health problem in Latin America and an emerging...Full Text Available

78

Taking social relationships seriously: Lessons learned from the informed consent practices of a vaccine trial on the Kenyan Coast  

UK PubMed Central (United Kingdom)

AbstractIndividual informed consent is a key ethical obligation for clinical studies, but empirical studies show that key requirements are often not met. Common recommendations to strengthen...Full Text Available

2008-09-01

79

Syndecan-Fc Hybrid Molecule as a Potent In Vitro Microbicidal Anti-HIV-1 Agent?  

UK PubMed Central (United Kingdom)

In the absence of a vaccine, there is an urgent need for the development of safe and effective topical microbicides to prevent the sexual transmission of human immunodeficiency virus type 1 (HIV-1)....Full Text Available

2010-07-01

80

Strategies for the production of genetically identical monkeys by embryo splitting  

UK PubMed Central (United Kingdom)

Genetically identical rhesus monkeys would have tremendous utility as models for the study of human disease and would be particularly valuable for vaccine trials and tissue transplantation studies where...Full Text Available

81

Serum Concentrations of Antibodies Against Vaccine Toxoids in Children Exposed Perinatally to Immunotoxicants  

UK PubMed Central (United Kingdom)

BackgroundPolychlorinated biphenyls (PCBs) may cause immunotoxic effects, but the detailed dose–response relationship and possible vulnerable time windows of exposure are...Full Text Available

2010-10-01

82

Rubella screening and vaccination program for US Air Force trainees: an analysis of findings.  

UK PubMed Central (United Kingdom)

A preventive medicine program of rubella control for trainees at the Air Force Military Training Center, Lackland AFB, Texas, was begun in October 1977. Incoming trainees were screened for rubella susceptibility,...Full Text Available

1982-03-01

83

Regulatory compliance | Mott MacDonald  

Wastenet

...broad range of experience in designing and building research and development laboratories for products such as vaccines, blood and sera, biological products, medical devices, solid dosage forms , highly potent products and cytotoxic material. We also have experience in a range of modular laboratories for TSE research, ...

84

Prevention of clinical coliform mastitis in dairy cows by a mutant Escherichia coli vaccine.  

UK PubMed Central (United Kingdom)

A prospective cohort study was undertaken in two commercial California dairies. The treatment group, 246 cows, received three doses of a whole cell bacterin of J5 Escherichia coli (mutant of E. coli...Full Text Available

1989-07-01

85

Polyantigenic Interferon-? Responses Are Associated with Protection from TB among HIV-Infected Adults with Childhood BCG Immunization  

UK PubMed Central (United Kingdom)

BackgroundSurrogate immunologic markers for natural and vaccine-mediated protection against tuberculosis (TB) have not been identified.MethodsHIV-infected...Full Text Available

86

Poliomyelitis control in Israel, the West Bank and Gaza Strip: changing strategies with the goal of eradication in an endemic area.  

UK PubMed Central (United Kingdom)

Israel has faced the challenge presented by epidemic poliomyelitis by using different immunization strategies. In the 1950s, inactivated poliovirus vaccine (IPV) helped to reduce the total burden of...Full Text Available

1994-01-01

87

Plasminogen-125I responses in dogs to a single injection of urokinase and typhoid vaccine and to vascular injury  

UK PubMed Central (United Kingdom)

In vivo plasminogen responses to various stimuli were studied. Plasminogen-125I was prepared and used first for metabolic studies of plasminogen in control dogs. The average results were:...Full Text Available

1972-06-01

88

Peru-15, an improved live attenuated oral vaccine candidate for Vibrio cholerae O1.  

Science.gov (United States)

Cholera vaccine candidate Peru-15 was derived from a Vibrio cholerae O1 El Tor Inaba strain by deleting the cholera toxin genetic element, introducing the gene encoding cholera toxin B subunit into recA, and screening for nonmotility. In a controlled study, Peru-15 (2 x 10(8) cfu) was administered to 11 volunteers. No vaccinee developed diarrhea, and 10 of 11 had > 4-fold rises in vibriocidal antibody titers. One month later, 5 vaccinees and 5 control volunteers were challenged with wild type V. cholerae O1. Four of 5 controls developed diarrhea (mean, 1.9 L). Two Peru-15 vaccinees developed diarrhea, 1 with < 0.3 L and 1 with approximately 1.0 L; this latter volunteer had not developed a significant vibriocidal immune response to vaccination. Peru-15 shows promise as a single-dose, oral cholera vaccine that is safe, immunogenic, and protective. PMID:7561195

1995-10-01

89

Peptide Nanoparticles as Novel Immunogens: Design and Analysis of a Prototypic Severe Acute Respiratory Syndrome Vaccine  

UK PubMed Central (United Kingdom)

Severe acute respiratory syndrome (SARS) is an infectious disease caused by a novel coronavirus that cost nearly 800 lives. While there have been no recent outbreaks of the disease, the threat...Full Text Available

2009-01-01

90

Passive immunity to feline leukemia: evaluation of immunity from dams naturally infected and experimentally vaccinated.  

UK PubMed Central (United Kingdom)

Antibodies against feline leukemia virus (FeLV) and the feline oncornavirus-associated cell membrane antigen (FOCMA) were transferred from pregnant cats to their suckling kittens. All of these kittens...Full Text Available

1977-04-01

91

LOUSE-BORNE BACTERIAL PATHOGENS IN LICE (PHTHIRAPTERA) OF RODENTS AND CATTLE FROM EGYPT  

Science.gov (United States)

... were erroneous. The oriental rat flea, Xenopsylla cheopis Rothschild, is considered to be the primary vector of ... laboratory and production of Weigl's exanthematous typhus vaccine. In Maintenance of hum...

92

In vitro antigen-induced antibody responses to hepatitis B surface antigen in man. Kinetic and cellular requirements.  

UK PubMed Central (United Kingdom)

In this report we define the parameters of the human immune response after immunization with hepatitis B vaccine. 2 wk after booster immunization, there is significant spontaneous secretion of antibody...Full Text Available

1984-10-01

93

Improvement of a Dendritic Cell-Based Therapeutic Cancer Vaccine with Components of Toxoplasma gondii?  

UK PubMed Central (United Kingdom)

The use of dendritic cells (DCs) as a cellular adjuvant is a promising approach to the immunotherapy of cancer. It has previously been demonstrated that DCs pulsed ex vivo with Toxoplasma gondii...Full Text Available

2009-10-01

94

Immunization of foxes by the intestinal route using an inactivated rabies vaccine.  

UK PubMed Central (United Kingdom)

Approximately 30% of foxes given two doses of an inactivated rabies antigen delivered directly into the intestinal tract developed an immune response as measured by rabies serum neutralizing antibodies....Full Text Available

1989-01-01

95

Genomic Expression Libraries for the Identification of Cross-Reactive Orthopoxvirus Antigens  

UK PubMed Central (United Kingdom)

Increasing numbers of human cowpox virus infections that are being observed and that particularly affect young non-vaccinated persons have renewed interest in this zoonotic disease. Usually causing...Full Text Available

96

Genomic Content of Bordetella pertussis Clinical Isolates Circulating in Areas of Intensive Children Vaccination  

UK PubMed Central (United Kingdom)

BackgroundThe objective of the study was to analyse the evolution of Bordetella pertussis population and the influence of herd immunity in different areas of the...Full Text Available

97

Evaluation of Two Homologous Proline-Rich Proteins of Coccidioides posadasii as Candidate Vaccines against Coccidioidomycosis?  

UK PubMed Central (United Kingdom)

Evaluation of the protective efficacy of recombinant T-cell-reactive proteins of Coccidioides posadasii in a murine model of coccidioidomycosis has led to the discovery of potential...Full Text Available

2007-12-01

98

Emulsified Nanoparticles Containing Inactivated Influenza Virus and CpG Oligodeoxynucleotides Critically Influences the Host Immune Responses in Mice  

UK PubMed Central (United Kingdom)

BackgroundAntigen sparing and cross-protective immunity are regarded as crucial in pandemic influenza vaccine development. Both targets can be achieved by adjuvantation strategy...Full Text Available

99

Dengue virus-specific murine T-lymphocyte proliferation: serotype specificity and response to recombinant viral proteins.  

UK PubMed Central (United Kingdom)

Definition of the T-lymphocyte responses to dengue viruses should aid in the development of safe and effective vaccines and help to explain the pathophysiology of dengue hemorrhagic fever and dengue...Full Text Available

1989-06-01

100

Dengue virus protein recognition by virus-specific murine CD8+ cytotoxic T lymphocytes.  

UK PubMed Central (United Kingdom)

The identification of the protein targets for dengue virus-specific T lymphocytes may be useful for planning the development of subunit vaccines against dengue. We studied the recognition by murine...Full Text Available

1993-02-01

101

CDC - Seasonal Influenza (Flu) - Questions and Answers - Guillain...  

Science.gov (United States)

Effectiveness Flu Shot Nasal Spray Vaccine (LAIV) Thimerosal Guillain-Barré Syndrome (GBS) Antiviral Drugs: Key Facts Antiviral Drugs: Q&A Antiviral Drug Resistance Links,...

2011-09-24

102

CDC - Malaria - Malaria Worldwide - How Can Malaria Cases and...  

Science.gov (United States)

vaccination card during trial enrollment at the KEMRI/CDC site in Kenya. (Alan Rubin, KEMRI) KEMRI Clinical Officer Paul Ogai reviews a prospective participant's...

2011-09-24

103

Auditing the Management of Vaccine-Preventable Disease Outbreaks: The Need for a Tool  

UK PubMed Central (United Kingdom)

Public health activities, especially infectious disease control, depend on effective teamwork. We present the results of a pilot audit questionnaire aimed at assessing the quality of public health services...Full Text Available

104

Malnutrition, Gut-Microbial Interactions and Mucosal Immunity to Vaccines, 07 Nov 2011 - 11 Nov 2011, Le Meridien New Delhi, New Delhi, India - SciDe  

Wastenet

... A better understanding of the links between nutrients, the gut microbiome and the intestinal immune system is likely to pave the way to the development of innovative approaches that target activation of specific immunological pathways for promoting the hostrsquo;s gut defense. Such knowledge should positively impact on the development of vaccine formulations and intervention strategies for improved control of enteric infections in developing countries. Registration fees # The Registration Fee is $715.00 on and before September 7, 2011. # After September 7, 2011, the ...

105

Immunological correlates for protection against intranasal challenge of Bacillus anthracis spores conferred by a protective antigen-based vaccine in rabbits.  

Science.gov (United States)

Correlates between immunological parameters and protection against Bacillus anthracis infection in animals vaccinated with protective antigen (PA)-based vaccines could provide surrogate markers to evaluate the putative protective efficiency of immunization in humans. In previous studies we demonstrated that neutralizing antibody levels serve as correlates for protection in guinea pigs (S. Reuveny et al., Infect. Immun. 69:2888-2893, 2001; H. Marcus et al., Infect. Immun. 72:3471-3477, 2004). In this study we evaluated similar correlates for protection by active and passive immunization of New Zealand White rabbits. Full immunization and partial immunization were achieved by single and multiple injections of standard and diluted doses of a PA-based vaccine. Passive immunization was carried out by injection of immune sera from rabbits vaccinated with PA-based vaccine prior to ...

2006-01-01

106

Immunogenicity, efficacy, safety and effectiveness of pneumococcal conjugate vaccines (1998-2006).  

Science.gov (United States)

In this paper we present an overview of the literature on efficacy and safety trials of the various pneumococcal conjugate vaccines on the market (PCV7) and in development (PCV9, PCV11 and allegedly PCV10 and PCV13), as well as of observations from post-licensure studies. Seven- (PCV7) and nine-valent PCV (PCV9) are reported to be sufficiently immunogenic after administration of a 3+1 schedule in infants in various RCTs. PncOMPC (PCV7 with a protein of N. meningitidis as a carrier) is less immunogenic, though this may have no repercussions for the protective efficacy against clinical disease. PCV7 is 82-97% efficacious against vaccine serotype (VT) IPD, 90% efficacious against (clinically diagnosed) pneumococcal pneumonia, and, like the 11-valent PCV, 57% efficacious against VT acute otitis media. Naturally, it would be of paramount public health interest if the same levels of efficacy and effectiveness could be achieved with fewer doses. ...

2006-12-04

107

Genetic control of immune response to pseudorabies and atrophic rhinitis vaccines: II. Comparison of additive direct and maternal genetic effects.  

Science.gov (United States)

Data from 52 litters farrowed in two seasons of a cross-fostering experiment were analyzed to estimate variances and covariances for additive direct and maternal genetic effects on immune response to pseudorabies virus and B. bronchiseptica vaccine. Twenty purebred boars and 44 sows of the Duroc, Landrace and Yorkshire breeds were used. Immune response was measured after vaccine challenge. A modified-live pseudorabies (PR) vaccine was administered to piglets at 28 d of age; response was measured by log2 serum neutralization titers at 56 d. An inactivated B. bronchiseptica bacterin was administered at 28, 42 and 112 d. Antibody levels were measured relative to positive and negative controls at 28, 56 and 119 d by using an enzyme-linked immunosorbent assay (ELISA). Results from this study for heritability were .18 +/- .09 for PR titer and .15 +/- .07 and .52 +/- .15 for 56- and 119-d ELISA values, respectively. The ...

1987-02-01

108

Serotypes and susceptibilities of paediatric clinical isolates of Streptococcus pneumoniae in Crete, Greece, before and after the heptavalent pneumococcal conjugate vaccine.  

Science.gov (United States)

All Streptococcus pneumoniae strains isolated from paediatric clinical samples at Heraklion University General Hospital in the 10-year period 2000-2009 were tested for serotype and susceptibility to antimicrobials. Among a total of 258 strains, 159 were isolated in the 5-year period 2000-2004, before the introduction of the heptavalent pneumococcal conjugate vaccine (PCV7), and 99 in the post-PCV7 5-year period 2005-2009. The prevalence of PCV7-included serotypes decreased in the post-PCV7 period (p?=?0.0002), but an increase was observed for serotypes 7F (p?=?0.002) and 19A (p?=?0.004). Pan-susceptibility rates and susceptibility to cotrimoxazole increased in the post-PCV7 period (p?=?0.01 and p?=?0.008, respectively), but serotype 19A emerged as a contributor to multi-resistance (p?=?0.007). PCV7 was followed by decreased S. pneumoniae resistance and prevalence of vaccine-related serotypes but increased prevalence of serotypes 7F and 19A. ...

2010-07-10

109

Construction and evaluation of a double mutant of Shigella flexneri as a candidate for oral vaccination against shigellosis.  

Science.gov (United States)

Based on studies on the genetic and molecular basis of Shigella flexneri invasive properties, we have constructed and evaluated a double mutant of S. flexneri serotype 5 for utilization as a live attenuated oral vaccine against shigellosis. The first mutation, icsA, blocks intracellular spread of bacteria as well as cell-to-cell infection. It affects the capacity of the invasive pathogen to form large abscesses in epithelia. The second mutation, iuc, eliminates production of the siderophore aerobactin thus impairing growth of the bacterium within tissues. This double mutant, SC5700 appeared safe when administered intragastrically to macaque monkeys as three doses (5 x 10(10) c.f.u. each) at weekly intervals. Protection against a challenge by the wild type isolate (M90T) was observed 4 weeks after the last vaccine inoculation. Duration of carriage was considerably reduced as compared to the control group in which all animals had developed severe ...

1989-10-01

111

Review on the immunology of European sea bass Dicentrarchus labrax  

British Library Electronic Table of Contents (United Kingdom)

European sea bass (Dicentrarchus labrax L.) is a marine species of great economic importance, particularly in Mediterranean aquaculture. However, numerous pathogenic viruses, bacteria, fungi and parasites affect the species, causing various infectious diseases and thereby leading to the most heavy losses in aquaculture production of sea bass. In this respect, knowledge on molecular and genetic mechanisms of resistance to pathogens and specific features of immune response against various infectious agents should greatly benefit the development of effective vaccines and proper vaccination strategies in marker-assisted selection of fish resistant to a range of infections. To date, genetic knowledge on sea bass immune regulatory genes responsible for resistance to pathogens is relatively poor ...

2007-01-01

112

Intravaginal immunization using the recombinant HIV-1 clade-C trimeric envelope glycoprotein CN54gp140 formulated within lyophilized solid dosage forms  

British Library Electronic Table of Contents (United Kingdom)

Vaccine-mediated prevention of primary HIV-1 infection at the heterosexual mucosal portal of entry may be facilitated by highly optimised formulations or drug delivery devices for intravaginal (i.vag) immunization. Previously we described hydroxyethylcellulose (HEC)-based rheologically structured gel vehicles (RSVs) for vaginal immunization of an HIV-1 vaccine candidate, a soluble recombinant trimeric HIV-1 clade-C envelope glycoprotein designated CN54gp140. Here we investigated the efficacy of lyophilized solid dosage formulations (LSDFs) for prolonging antigen stability and as i.vag delivery modalities. LSDFs were designed and developed that upon i.vag administration they would reconstitute with the imbibing of vaginal fluid to mucoadhesive, site-retentive semi-solids. Mice were immunize...

2011-01-01

113

Cochrane Review: Polysaccharide vaccines for preventing serogroup A meningococcal meningitis  

British Library Electronic Table of Contents (United Kingdom)

AbstractBackground Randomised controlled trials (RCTs) in the 1970s and early 1980s showed the polysaccharide serogroup A vaccine (SgAV) prevented serogroup A meningococcal meningitis (SGAMM). Subsequent non-RCTs suggested significant variations in the age-specific duration of protection among children. Objectives To determine the protective effect, duration of protection, age-specific effects and the effect of booster doses in children of the SgAV against SGAMM. Search strategy We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2010, issue 2) which contains the Acute Respiratory Infections Group's Specialised Register, MEDLINE (January 1950 to May Week 3, 2010) and EMBASE (January 1974 to May 2010). Selection criteria We included RCTs. Non-RCTs ...

2011-01-01

114

Radiation technology of wood-plastic composite materials  

International Nuclear Information System (INIS)

... radiation effects RADIATIONS. WOOD-PLASTIC COMPOSITES.

1981-10-02

115

Nano-Materials in Metal-Matrix Composites  

International Science & Technology Center (ISTC)

Metal Matrix Composites on the Basis of Nano-Materials

116

Multifunctional Composite Coating  

International Science & Technology Center (ISTC)

New Composite Multifunctional Coatings Produced Using SHS-Electrodes

117

Electrodepositing Nanostructured Composite Coatings  

International Science & Technology Center (ISTC)

Development of the Method of Electrodepositing Nanostructured Composite Coatings with Improved Engineering Properties

118

Ceramic Composite Materials  

International Science & Technology Center (ISTC)

Development of Ceramic Composite Materials and Structural Elements for High-Temperature Nuclear Reactors

119

Translation products of pre-S(1), pre-S(2) regions and the S gene of hepatitis B virus: susceptibility of their antigenic activities to treatment with heat, urea formalin or pepsin  

UK PubMed Central (United Kingdom)

Hepatitis B subviral particles, purified from plasma of asymptomatic carriers seropositive for hepatitis B e antigen, were treated with various conditions reported for the processing of vaccines. Thereafter,...Full Text Available

1986-12-01

120

Serum and salivary responses to oral tetravalent reassortant rotavirus vaccine in newborns.  

UK PubMed Central (United Kingdom)

Serum and salivary responses of 95 infants to either a standard (4 x 10(4) plaque-forming units (PFU), 47 neonates) or a high dose (4 x 10(5) PFU, 48 neonates) of tetravalent reassortant rhesus rotavirus...Full Text Available

1993-05-01

121

Safety and immunogenicity of ERA strain of rabies virus propagated in a BHK-21 cell line.  

UK PubMed Central (United Kingdom)

The ERA strain of rabies virus was propagated in a baby hamster kidney cell line (BHK-21/C13). The viral titer was 10(1.8) tissue culture infective doses (TCID) higher than that of commercial ERA vaccine....Full Text Available

1989-10-01

122

Recruitment of intestinal CD45RA+ and CD45RC+ cells induced by a candidate oral vaccine against porcine post-weaning colibacillosis.  

Science.gov (United States)

To assess the influence of a live attenuated oral vaccine against porcine post-weaning colibacillosis (PWC) induced by enterotoxigenic Escherichia coli (ETEC) on mucosal lymphoid cell CD45 isoforms expression, experimental group of weaned pigs (n=6) was immunized orally with F4ac+ non-ETEC strain (day 0) and challenged with F4ac+ ETEC strain 7 days latter. Non-immunized ETEC-infected pigs (n=6) served as control. All pigs were killed on post-challenge day 7. The small intestine was excised for isolation of jejunal lamina propria (JLP) and ileal Peyer's patch (IPP) lymphocytes and immunohistochemical studies. The results obtained by immunophenotyping of isolated cells show that the proportion of CD45RA+ and CD45RC+ JLP, but not IPP, cells were higher in the non-ETEC-immunized ETEC-infected pigs versus non-immunized infected. Additionally, while CD45RA+ JLP cells increased only slightly, the expression of CD45RC isoform on the JLP cells was significantly higher ...

2002-07-01

123

Murine antibody response to oral infection with live aroA recombinant Salmonella dublin vaccine strains expressing filamentous hemagglutinin antigen from Bordetella pertussis.  

Science.gov (United States)

Two plasmids which express either nearly intact or truncated filamentous hemagglutinin (FHA) from Bordetella pertussis and which are marked with a tetracycline resistance (Tcr) gene were transformed into Salmonella dublin SL1438, an aroA deletion mutant intended for use as an attenuated oral vaccine against salmonellosis. These S. dublin recombinants, when fed to mice, induced serum immunoglobulin, immunoglobulin M (IgM), and sometimes IgA antibody responses to FHA and S. dublin. In addition, IgA antibodies against FHA were found in gut wash fluids. S. dublin carrying pDB2300, a multicopy plasmid encoding truncated FHA protein, induced a better antibody response than did S. dublin carrying pDB2000, a low-copy-number plasmid encoding full-sized FHA. Administration of tetracycline to mice enhanced the stability of recombinant plasmids, and tetracycline-treated mice developed higher anti-FHA titers. Although neither strain examined is suitable for use in a human oral ...

1990-08-01

124

Invasiveness and persistence of Salmonella enteritidis, Salmonella typhimurium, and a genetically defined S. enteritidis aroA strain in young chickens.  

UK PubMed Central (United Kingdom)

Newly hatched chicks were dosed orally with a Salmonella typhimurium wild-type strain, an S. enteritidis wild-type strain, and a genetically defined S. enteritidis aroA vaccine candidate, strain CVL30....Full Text Available

1994-11-01

125

Interferon-? expressed by a rabies virus-based HIV-1 vaccine vector serves as a molecular adjuvant and decreases pathogenicity  

UK PubMed Central (United Kingdom)

Type I interferon is important in anti-viral responses and in coordinating the innate immune response. Here we explore the use of interferon-β to adjuvant the response to a rabies virus...Full Text Available

2008-12-20

126

Induction of Antibody Responses to African Horse Sickness Virus (AHSV) in Ponies after Vaccination with Recombinant Modified Vaccinia Ankara (MVA)  

UK PubMed Central (United Kingdom)

BackgroundAfrican horse sickness virus (AHSV) causes a non-contagious, infectious disease in equids, with mortality rates that can exceed 90% in susceptible horse populations....Full Text Available

127

Helper T-Cell Epitopes Encoded by the Babesia bigemina rap-1 Gene Family in the Constant and Variant Domains Are Conserved among Parasite Strains  

UK PubMed Central (United Kingdom)

Among important candidates for babesial vaccines are apical complex proteins, including rhoptry-associated protein 1 (RAP-1) from Babesia bovis and B. bigemina, which...Full Text Available

1998-04-01

128

Differential Specificity and Immunogenicity of Adenovirus Type 5 Neutralizing Antibodies Elicited by Natural Infection or Immunization?  

UK PubMed Central (United Kingdom)

A recent clinical trial of a T-cell-based AIDS vaccine delivered with recombinant adenovirus type 5 (rAd5) vectors showed no efficacy in lowering viral load and was associated with increased risk of...Full Text Available

2010-01-01

129

A progress for the health of south countries. The solar refrigerator; Un progres pour la sante dans les pays du Sud. Le refrigerateur solaire  

Energy Technology Data Exchange (ETDEWEB)

In order to conserve vaccines in hot countries a solar refrigerator has been made by a French university. It is a photothermal refrigerator without batteries. It uses two gases: ammonia and calcium chloride. The refrigerator is autonomous and can work eleven days without sun. (N.C.)

1998-05-01

130

Light Weight Composite Mirrors for Science Instruments  

Science.gov (United States)

Light Weight Composite Mirrors for Science Instruments. Composite Optics, Inc. San Diego, CA. INNOVATION. Light weight, large aperture reflectors of graphite ...

139

Thermodynamic Stable Metal Compositions  

International Science & Technology Center (ISTC)

Thermodynamic Stable Metal Compositions for Improvement of an Operational Safety of Constructional Materials under Conditions of Multifactor Loadings of an Aggressive Environment

140

Shock and Impact Response of Naval Composite Structures  

Science.gov (United States)

... at the end of this report. A. Low-Velocity Impact of Composite Sandwich Panels In 2007, the PI developed analytical solutions ...

2010-08-09

141

Nondestructive Testing of Polymeric Composite Sandwich ...  

Science.gov (United States)

... Accession Number : ADD345858. Title : Nondestructive Testing of Polymeric Composite Sandwich Panels Via the Thermographic Halo,. ...

142

MINEQL-PC. Chemical Equilibrium Composition of Aqueous Systems  

Energy Technology Data Exchange (ETDEWEB)

MINEQL is a subroutine package to calculate equilibrium composition of an aqueous system, accounting for mass transfer.

1986-11-21

143

Liquid hydrocarbon fuel composition  

Energy Technology Data Exchange (ETDEWEB)

A fuel composition comprising a liquid hydrocarbon fuel and a detergent amount of the product of reaction between a polyamine and a stearic acid is described.

1983-07-19

144

Damage and Repair of the APS Graphite/Epoxy Composite ...  

Science.gov (United States)

... Abstract : High temperature testing of graphite/epoxy laminates and composite sandwich panels was performed while the Shuttle was on orbit to ...

1982-10-12

145

DARPA Program Composition for Embedded Systems (PCES) ...  

Science.gov (United States)

... Title : DARPA Program Composition for Embedded Systems (PCES) Program Capstone Demonstration Video (Postprint) (CD-ROM). ...

2005-09-01

146

Computational Simulation - NASA Technical Report Server (NTRS)  

Science.gov (United States)

the progressive simplification of composite sandwich panels. The equations ... The thermal and structural behavior of composite sandwich panels with a ...

147

Carbon Fiber Reinforced Glass Matrix Composites for Satellite ...  

Science.gov (United States)

... The ultimate compressive strength (UCS) for the HMU/BSG composite is essentially equivalent to the tensile strength exhibited by this system. ...

1992-06-01

148

Advances and challenges of wood polymer composites  

Science.gov (United States)

... polypropylene, polylactic acid and polyvinyl chloride to form wood plastic composites (WPC). WPCs have seen a large growth in ... ...

149

Advanced Composites for Aerospace Require Waterjet ...  

Science.gov (United States)

... Accession Number : ADD808679. Title : Advanced Composites for Aerospace Require Waterjet Technology. Descriptive Note : Journal article. ...

1992-09-01

150

Efficient mitigation strategies for epidemics in rural regions  

CERN Document Server

Containing an epidemic at its origin is the most desirable mitigation. Epidemics have often originated in rural areas, with rural communities among the first affected. Disease dynamics in rural regions have received limited attention, and results of general studies cannot be directly applied since population densities and human mobility factors are very different in rural regions from those in cities. We create a network model of a rural community in Kansas, USA, by collecting data on the contact patterns and computing rates of contact among a sampled population. We model the impact of different mitigation strategies detecting closely connected groups of people and frequently visited locations. Within those groups and locations, we compare the effectiveness of random and targeted vaccinations using a Susceptible-Exposed-Infected-Recovered compartmental model on the contact network. Our simulations show that the targeted vaccinations of only 10% ...

2010-01-01

151

Clinical aspects of Marburg hemorrhagic fever  

British Library Electronic Table of Contents (United Kingdom)

Marburg virus belongs to the genus Marburgvirus in the family Filoviridae and causes a severe hemorrhagic fever, known as Marburg hemorrhagic fever (MHF), in both humans and nonhuman primates. Similar to the more widely known Ebola hemorrhagic fever, MHF is characterized by systemic viral replication, immunosuppression and abnormal inflammatory responses. These pathological features of the disease contribute to a number of systemic dysfunctions including hemorrhages, edema, coagulation abnormalities and, ultimately, multiorgan failure and shock, often resulting in death. A detailed understanding of the pathological processes that lead to this devastating disease remains elusive, a fact that contributes to the lack of licensed vaccines or effective therapeutics. This article will review the...

2011-01-01

152

Hybrid Composites Made from Oil Palm Empty Fruit Bunches/Jute Fibres: Water Absorption, Thickness Swelling and Density Behaviours  

British Library Electronic Table of Contents (United Kingdom)

In this research, hybrid composite materials were prepared from combination of oil palm Empty fruit bunches (EFB) fibre and jute fibre as reinforcement, epoxy as polymer matrix. This study intended to investigate the effect of jute fiber hybridization and different layering pattern on the physical properties of oil palm EFB-Epoxy composites. Water absorption and thickness swelling test reveal that hybrid composite shows a moderate water absorption which is 11.20% for hybrid EFB/Jute/EFB composite and 6.08% for hybrid Jute/EFB/Jute composite. The thickness swelling and water absorption of the hybrid composites slightly increased as the layering pattern of hybrid composites changed. Hybrid composites are more water resistance and dimensional stable compare to the pure EFB composites. This is...

2011-01-01

153

The viscoelastic composite with interface debonding  

British Library Electronic Table of Contents (United Kingdom)

The effect of particle/matrix interface debonding on composites consisting of elastic particles and viscoelastic matrix is studied. The interface debonding is represented by a nonlinear cohesive law for the high explosive PBX 9501. The Mori-Tanaka method gives the constitutive relation of the composite in terms of the properties of elastic particles, viscoelastic matrix, and nonlinear cohesive law for interfaces. For the example of a composite with spherical particles subject to hydrostatic tension, simple analytical expressions of the composite stress-strain relation are obtained. The strain rate and temperature have strong effects on the composite behavior. High strain rate and low temperature give high strength of the composite. However, the rate and temperature effects decrease as the ...

2008-01-01

154

Hydrothermal synthesis of tobermorite/hydroxyapatite composites  

British Library Electronic Table of Contents (United Kingdom)

A tobermorite/hydroxyapatite composite was prepared by hydrothermal treatment using diatomaceous earth, ?-tricalcium phosphate and slaked lime starting materials. The XRD patterns of the composite confirmed that tobermorite and hydroxyapatite were formed after the hydrothermal process. The bending strength of the composite reached a level higher than 9?MPa after the hydrothermal process. The development of the bending strength was due to the formation of tobermorite and hydroxyapatite during the hydrothermal process. The composite had a high specific surface area due to these newly formed crystals.

2008-01-01

155

Electrochemical stability of silicon/carbon composite anode for lithium ion batteries  

International Nuclear Information System (INIS)

Silicon/carbon composite anode materials were prepared by pyrolyzing the phenol-formaldehyde resin (PFR) mixed with silicon and graphite powders. Scanning electron microscopic (SEM) observation showed that the morphology stability of the composite electrodes can be retained during cycling. A structure evolution mechanism is proposed to illuminate the enhancement of cycleability of the composite electrode. The composite used as anode material for lithium ion batteries possesses a reversible capacity of over 700 mAh/g.

2007-04-20

156

Catalysis over activated zeolites  

Science.gov (United States)

A process is provided for conducting organic compound conversion over a catalyst composition comprising a supported crystalline zeolite having a high initial silica-to-alumina mole ratio, said supported zeolite being prepared by compositing said crystalline zeolite with alumina, reacting the composite with a particular hydrogen fluoride solution in a specified way, drying the hydrogen fluoride reacted composite, treating the dried composite by hydrolysis, ammonolysis and/or by contact with an ammonium salt solution, and calcining the resulting material.

1985-02-19

157

Study of wood plastic composite in the presence of nitrogen containing additives  

Energy Technology Data Exchange (ETDEWEB)

Effect of nitrogen-containing additives in the study of wood plastic composites of MMA with simul and mango wood of Bangladesh has been investigated. Nine different additives were used and the additives containing carboamide group induce the highest tensile strength to the composite. (author).

1994-10-01

158

Study of wood plastic composite in the presence of nitrogen containing additives  

International Nuclear Information System (INIS)

Effect of nitrogen-containing additives in the study of wood plastic composites of MMA with simul and mango wood of Bangladesh has been investigated. Nine different additives were used and the additives containing carboamide group induce the highest tensile strength to the composite. (author).

1994-01-01

159

Study of wood plastic composite in the presence of nitrogen containing additives  

Science.gov (United States)

Effect of nitrogen-containing additives in the study of wood plastic composites of MMA with simul and mango wood of Bangladesh has been investigated. Nine different additives were used and the additives containing carboamide group induce the highest tensile strength to the composite.

1994-10-01

160

Potentials for composites from agro-based fibers  

Energy Technology Data Exchange (ETDEWEB)

A composite is any combination of two or more resources held together by some type of mastic or matrix. This report will describe several different types of composites with regard to thermoplasticization, improved mechanical properties, and stiffness.

1995-12-01

161

Physical Morphology and Quantitative Characterization of Chemical Changes of Weathered PVC/Pine Composites.  

Science.gov (United States)

This study investigated weathering effects on polyvinyl chloride (PVC) based wood plastic composites (WPC), with a focus on the color and structure that is attributed to the material composition. It is directed towards quantifying the main chemical modifi...

2009-01-01

162

Osteoblast response to dimethacrylate composites varying in composition, conversion and roughness using a combinatorial approach  

UK PubMed Central (United Kingdom)

Dimethacrylate polymers and composites are seeing increased usage in orthopedics. As these applications require the material to integrate with the surrounding tissues, direct contact cytotoxicity...Full Text Available

2009-09-01

163

Wear resistant composite structure of vitreous carbon containing convoluted fibers. Quarterly report No. 4  

Energy Technology Data Exchange (ETDEWEB)

This report presents a brief description of the fabrication and advantages of a composite, carbon-metal fiber material which does not require lubrication.

1995-05-01

164

Relationship of source and sink in determining kernel composition of maize  

UK PubMed Central (United Kingdom)

The relative role of the maternal source and the filial sink in controlling the composition of maize (Zea mays L.) kernels is unclear and may be influenced by the genotype and the N...Full Text Available

2010-01-01

165

Preparation of covalently modified organic-inorganic composite nanoparticles and their interfacial electron transfer researches  

CERN Document Server

Preparation of covalently modified organic-inorganic composite nanoparticles and their interfacial electron transfer researches

1998-01-01

166

Predictions of Thermal Buckling Strengths of Hypersonic ... - NASA  

Science.gov (United States)

Composite Sandwich Panels under Different Thermal Environments, Composite Structures, Vol. 25,. July 1993, pp. 227239. 11. Ko, William L., Mechanical and ...

168

Metal phthalocyanine catalysts  

Energy Technology Data Exchange (ETDEWEB)

As a new composition of matter, alkali metal or ammonium or tetraalkylammonium diazidoperfluorophthalocyanatoferrate. Other embodiments of the invention comprise compositions wherein the metal of the coordination complex is cobalt, manganese and chromium.

1994-01-01

169

Measurements of the concentration and composition of nuclei for cirrus formation  

UK PubMed Central (United Kingdom)

This article addresses the need for new data on indirect effects of natural and anthropogenic aerosol particles on atmospheric ice clouds. Simultaneous measurements of the concentration and composition...Full Text Available

2003-12-09

170

Instrumeted Impact Testing of Composite Sandwich Panels,  

Science.gov (United States)

... Accession Number : ADD442819. Title : Instrumeted Impact Testing of Composite Sandwich Panels,. Corporate Author : AUBURN UNIV AL. ...

1989-05-01

171

Indirect resin composites  

UK PubMed Central (United Kingdom)

Aesthetic dentistry continues to evolve through innovations in bonding agents, restorative materials, and conservative preparation techniques. The use of direct composite restoration in posterior teeth...Full Text Available

2010-10-01

172

Fiber Reinforced Superalloys - NASA Technical Reports Server  

Science.gov (United States)

hlgh fiber content composites met the minlmum requirements. (1400 O F ) , the hlgher fiber content as-fabricated composites have impact strengths distinctly ...

173

Energy Finite Element Analysis ... - NASA Technical Reports Server  

Science.gov (United States)

structures made out of composite laminates and/or composite sandwich panels. A Spectral Finite Element Method (SFEM) [19, 20] is used for evaluating the ...

174

Design of Damage-Tolerant Composite Sandwich Panels with Tear Straps  

Science.gov (United States)

The objectives of the Phase-I research address the development of mechanics- based structural integrity analysis methodologies for composite sandwich panels ...

175

Composition of the Scientific Policy Committee Appointment of Two New Members by the Chairman of the Committee (J. Specht, A. Wroblewski)  

CERN Document Server

Composition of the Scientific Policy Committee Appointment of Two New Members by the Chairman of the Committee (J. Specht, A. Wroblewski)

1993-01-01

176

Composite vector leptoquarks in [ital e][sup +][ital e[minus  

Energy Technology Data Exchange (ETDEWEB)

We study the signals for composite vector leptoquarks in [ital e][sup +][ital e[minus

1993-02-01

177

A Composite Architecture for Network Security at JPL Robert B ...  

Science.gov (United States)

A Composite Architecture for Network Security at JPL. Robert B. Mead, Tom G. Dearmond, and Joseph S. Sherif. JPL, California Institute of Technology ...

178

A Composite Architecture for Network Security at JPL  

Science.gov (United States)

We advance a tentative composite model for computer security at JPL, together with inter and intra networking with other NASA centers and overseas clients.

1998-01-01

179

Science and Technology Review July/August 2010  

Energy Technology Data Exchange (ETDEWEB)

This issue has the following articles: (1) Deterrence with a Minimum Nuclear Stockpile - Commentary by Bruce T. Goodwin; (2) Enhancing Confidence in the Nation's Nuclear Stockpile - Livermore experts are participating in a national effort aimed at predicting how nuclear weapon materials and systems will likely change over time; (3) Narrowing Uncertainties - For climate modeling and many other fields, understanding uncertainty, or margin of error, is critical; (4) Insight into a Deadly Disease - Laboratory experiments reveal the pathogenesis of tularemia in host cells, bringing scientists closer to developing a vaccine for this debilitating disease. (5) Return to Rongelap - On the Rongelap Atoll, Livermore scientists are working to minimize radiological exposure for natives now living on or wishing to return to the islands.

2010-05-27

180

Novel Techniques and Their Wide Applications to Health Foods, Medical and Agricultural Biotechnology in Relation to Policy Making on Genetically Modified Crops and Foods  

CERN Document Server

Selected applications of novel techniques in Agricultural Biotechnology, Health Food formulations and Medical Biotechnology are being reviewed with the aim of unraveling future developments and policy changes that are likely to open new markets for Biotechnology and prevent the shrinking or closing of existing ones. Amongst the selected novel techniques with applications in both Agricultural and Medical Biotechnology are: immobilized bacterial cells and enzymes, microencapsulation and liposome production, genetic manipulation of microorganisms, development of novel vaccines from plants, epigenomics of mammalian cells and organisms, and biocomputational tools for molecular modeling related to disease and Bioinformatics. Both fundamental and applied aspects of the emerging new techniques are being discussed in relation to their anticipated, marked impact on future markets and present policy changes that are needed for success in either Agricultural or Medical ...

2004-01-01

181

Low cytotoxicity effect of dendrosome as an efficient carrier for rotavirus VP2 gene transferring into a human lung cell line  

British Library Electronic Table of Contents (United Kingdom)

The efficiency of dendrosome (a gene porter) was assessed in transferring recombinant human rotavirus VP2 cDNA into A549, a human lung cell line. After gene transferring, transmission electron microscopy showed core-like particles (CLPs) formation in the transfected cells both with dendrosome and lipofectamine porters. In addition, western blotting analysis showed that the expression of VP2 gene was almost equal in the dendrosome and lipofectamine-transfected cells. Also, the cytotoxicity studies revealed that dendrosome had a lower cytotoxicity than lipofectamine. Therefore, our study may introduce dendrosome as a possible carrier for gene transferring into the human lung cell line, especially, for intranasally administration of DNA vaccines.

2009-01-01

182

Global suppression of mitogen-activated ovine peripheral blood mononuclear cells by surface protein activity from Mycoplasma ovipneumoniae  

British Library Electronic Table of Contents (United Kingdom)

Mycoplasma ovipneumoniae is associated with chronic non-progressive pneumonia of sheep and goats. As with many other mycoplasmas involved in animal diseases, protective immune responses have not been achieved with vaccines, even though antibody responses can be obtained. This study focuses on characterizing the interaction of M. ovipneumoniae with ovine PBMC using carboxy-fluorescein-succinimidyl-ester (CFSE) loading and flow cytometry to measure lymphoid cell division. M. ovipneumoniae induced a strong in vitro polyclonal suppression of CD4^+, CD8^+, and B blood lymphocyte subsets. The suppressive activity could be destroyed by heating to 60^oC, and partially impaired by formalin and binary ethyleneimine treatment that abolished its viability. The activity resided on the surface-exposed m...

2010-01-01

183

Estimates of quantitative genetic parameters of immunological traits in the chicken.  

Science.gov (United States)

Three in vivo assays were used to measure the immunocompetence of chickens in two generations of a selection experiment. The obtained data were used to estimate the variance components for sire and dam for antibody production to Pasteurella multocida and Mycoplasma gallisepticum vaccines, for T-cell-mediated immunity evaluated by a phytohemagglutinin wing web assay, and for clearance of foreign particles from the circulatory system. Heritabilities of and genetic correlations among these immunological traits were calculated from the sire variance components. Heritability estimates of the immunological traits based on the sire component of variance ranged from .06 to .53, and genetic correlations among immunological traits were generally negative. PMID:1956847

1991-10-01

184

Diphtheria toxoid conformation in the context of its nanoencapsulation within liposomal particles sandwiched by chitosan  

British Library Electronic Table of Contents (United Kingdom)

Chitosan (a?-(1-4)-amino-2-deoxy-b?-D-glucan) is a deacetylated form of chitin, a polysaccharide from crustacean shells. Its unique characteristics, such as positive charge, biodegradability, biocompatibility, nontoxicity, and rigid structure, make this macromolecule ideal for an oral vaccine delivery system. We prepared reverse-phase evaporation vesicles (REVs) sandwiched by chitosan (Chi) and polyvinylic alcohol (PVA). However, in this method, there are still some problems to be circumvented related to protein stabilization. During the inverted micelle phase of protein nanoencapsulation, hydrophobic interfaces are expanded, leading to interfacial adsorption, followed by protein unfolding and aggregation. Here, spectroscopic and immunological techniques were used to ascertain the effects ...

2011-01-01

185

Complete genome sequences of Brucella melitensis strains M28 and M5-90, with different virulence backgrounds.  

Science.gov (United States)

Brucella melitensis is a Gram-negative coccobacillus bacteria belonging to the Alphaproteobacteria subclass. It is an important zoonotic pathogen that causes brucellosis, a disease affecting sheep, cattle, and sometimes humans. The B. melitensis strain M5-90, a live attenuated vaccine cultured from the B. melitensis virulent strain M28, has been an effective tool to control brucellosis in goats and sheep in China. Here we report the complete genome sequences of B. melitensis M28 and M5-90, strains with different virulence backgrounds, which will serve as a valuable reference for future studies. PMID:21478357

2011-04-08

186

Chloroquine for influenza prevention: a randomised, double-blind, placebo controlled trial  

British Library Electronic Table of Contents (United Kingdom)

Background: Chloroquine has in-vitro activity against influenza and could be an ideal candidate for worldwide prevention of influenza in the period between onset of a pandemic with a virulent influenza strain and the development and widespread dissemination of an effective vaccine. We aimed to assess the efficacy of such an intervention. Methods: In this randomised, double-blind, placebo-controlled trial done at a single centre in Singapore, we randomly assigned (1:1) healthy adults to receive chloroquine phosphate (500 mg/day for 1 week, then once a week to complete 12 weeks) or matching placebo by use of a computer-generated randomisation list. Participants filled an online symptom diary every week, supplemented by daily diaries and self-administered nasal swabs when unwell. Haemagglutin...

2011-01-01

187

Antigenic characterization of phocine distemper virus causing mass mortality in 2002 and its relationship to other morbilliviruses  

British Library Electronic Table of Contents (United Kingdom)

Summary The antigenic relationship between the phocine distemper virus (PDV) strain causing the epidemic in 2002 and the PDV strain of 1988, canine distemper virus from two dogs and one marten, and one measles virus strain was investigated in vivo and in vitro using monospecific polyclonal and monoclonal antibodies directed against five different proteins of canine or phocine distemper virus (N, P, M, F, H). Epitopic mapping revealed no difference between the PDV strains causing the epidemics in 1988 or 2002. However, the use of these antibodies allowed discrimination between different morbilliviruses including a vaccine strain of canine distemper virus. The major differences among the investigated morbilliviruses were found in the H protein.

2007-01-01

188

Wear resistant of Al{sub 2}O{sub 3}/heat-resistant steel at high temperature  

Energy Technology Data Exchange (ETDEWEB)

The high temperature abrasive wear resistant of the composites with different Al{sub 2}O{sub 3} volume fractions, particle coating and size were investigated and the failure action of composites under different conditions at high temperature was analyzed. The results showed that the high temperature abrasive wear resistant of composite with Ni coating and wide size and 39% volume fraction of particle is the best among all composites examined. (orig.)

2005-07-01

189

THE EFFECT OF FIBRE MISALIGNMENT ON THE ...  

Science.gov (United States)

... and testing of unidirectional composites, there are serious doubts about the possibility of obtaining a true ultimate compressive strength for this kind ...

197

Powder composites for gas-plasma ceramic coatings  

Energy Technology Data Exchange (ETDEWEB)

The method of production of xAl{sub 2}O{sub 3}-yTiO{sub 2} compositions provides for the depth distribution of coating components and specifies its mechanical properties. In case of the composition obtained by cladding, titanium is mainly concentrated at the substrate. In case of mechanical mixture or composition obtained by sintering the oxides, the depth distribution of coating components is random.

1995-12-31

201

MICROMECHANICS - COMPRESSIVE PROPERTIES OF ...  

Science.gov (United States)

... slenderness ratio. Equations which determine the ultimate compressive strength of a composite were established. Several ...

1965-05-01

204

Kevlar and carbon composites compared  

Energy Technology Data Exchange (ETDEWEB)

Characteristics of advanced composites are investigated. The fibers considered are Kevlar and carbon. The greatest advantage of composites over metals is emphasized, and lies in their permitting designers to obtain properties in exactly the locations desired. Kevlar replaced S-glass on the Trident 2 missile, saving 800 lbs. and adding 800 miles to its range. Military aircraft builders find that advanced carbon composites more often than not win out over Kevlar.

1985-02-01

215

Development and Fabrication of Compositions for 155-mm ...  

Science.gov (United States)

... Descriptors : *PROPELLING CHARGES, *NITROCELLULOSE, *COMBUSTIBLE CARTRIDGE CASES, DENSITY, FIBERS, MANUFACTURING ...

1982-10-01

221

An R&D Exploratory Investigation of Resin Binders for the ...  

Science.gov (United States)

... Descriptors : *POLYMERS, *BINDERS, *HOWITZERS, *COMBUSTIBLE CARTRIDGE CASES, CHEMICAL COMPOSITION, PROPELLING ...

1980-10-01

222

1993 - NASA  

Science.gov (United States)

... BUCKLING ANALYSIS OF METAL MATRIX COMPOSITE SANDWICH PANELS UNDER DIFFERENT THERMAL ENVIRONMENTS , Technical Memorandum ...

223

Role of additives in wood plastic composite of water soluble monomer  

International Nuclear Information System (INIS)

Wood plastic composites are prepared under radiation of "6"0Co gamma source with simul, a low grade wood of Bangladesh using a water soluble monomer acrylamide (AM) mixed with a swelling solvent methanol, water or methanol/water (1:1) at different compositions in the presence of a number of additives and co-additives such as NVP (N-vinylpyrrolidone), TPGDA (tripropylene glycol diacrylate), TMPTA (trimethylol propane triacrylate), sulfuric acid, urea and copper sulfate. Polymer loading (PL) and tensile strength (TS) of the composites are measured. The role of these additives on the composites is also discussed. It is observed that nitrogen-atom containing-materials like urea, NVP and AM produce composites with the highest mechanical strength, and incorporation of copper into this system provides additional property of protection and preservation of the composites ...

1994-01-01

224

Thermal characterization of rubberwood-polymer composites  

International Nuclear Information System (INIS)

The thermal properties of five types of radiation-induced wood-polymer composites based on a tropical hardwood, rubberwood (Hevea braziliensis), was studied by oxygen index measurement, differential thermal analysis (DTA) and thermogravimetry (TG). The DTA and TG curves of composites were different from those of rubberwood, which can be attributed to the presence of the incorporated polymers. Of the five composites, the one impregnated with bis(2-chloroethyl)vinyl phosphonate reduced the initial temperature of decomposition, increased the peak temperatures of exothermic reactions, and increased the char yield. Comparison with physical blends of rubberwood and the corresponding polymer provided some evidence of chemical interaction of wood and polymer in some of the composites. (author).

1989-01-01

225

Radiation induced polymerization of vinyl monomers and their application for preparation of wood-polymer composites  

International Nuclear Information System (INIS)

Polymerizing effects of high energy radiation has been found suitable for preparation of wood-polymer composites. In the present work after evaluating polymer products that have been obtained by irradiation method, wood-polymer composites have been prepared by in situ polymerization of vinyl acetate, acrylic acid and acrylic acid/styrene mixture using two samples of Iranian hardwoods, Beech and Hornbeam. These woods and their composites have been tested for their physical and mechanical properties. The results have shown that chemical bonding between polymer and the cell wall component lead to better strength properties in the composites. (author).

1992-09-01

226

Preparation of polyester/gypsum/composite using gamma radiation, and its radiation stability  

Energy Technology Data Exchange (ETDEWEB)

Composites based on pure gypsum and polyester-styrene resin have been prepared using various doses of gamma radiation. Some physical properties of the prepared composites and the influence of irradiation dose on it have been studied as: compression strength, hardness, thermal decomposition temperature in nitrogen or oxygen, and the change in weight in aqueous solutions with different pH values. The glass transition temperature of the pure polymer and the composites increases with increasing the irradiation dose up to a plateau, and the glass transition temperature of the pure polymer is lower than that of the composites. The irradiation dose does not seem to affect the decomposition temperature of the pure polymer or the composites significantly and the decomposition temperature in presence of nitrogen is higher than that in presence of oxygen. Increasing the irradiation dose leads ...

2005-06-01

227

Preliminary study on the development of EFB Fibre-sago starch composites: impact and flexural properties  

International Nuclear Information System (INIS)

There is growing interest in the use of natural fibres as the reinforcements for polymer composites in the automotive industry and as matrix for composites in building products application to replace synthetic fibres. In this respect the aim of this study is to develop an environmental friendly composites for furniture industry based on EFB fibres and sago starch. In this preliminary study, a basic composition and processing of EFB fibres-sago starch composites were established and the properties of the composites were determined. EFB fibre content was varied between 50-80% by weight. The amount of sago starch in liquid form was also varied and final weight percentage of sago starch added into the EFB fibres was adjusted accordingly. The mixtures of EFB fibres and sago starch were blended using Haake Rheomixer. The preliminary results indicate that the impact ...

2004-07-12

228

Microstructure and mechanical properties of quasi-carbon fibers and their polyacrylonitrile matrix composites  

Energy Technology Data Exchange (ETDEWEB)

Quasi-carbon fibers (QCFs) were prepared from Polyacrylonitrile (PAN) precursor by pyrolysis in the temperature range from 400{degrees}C to 950{degrees}C. The QCF-reinforced composites were fabricated by impregnating the QCFs with the PAN resin. The microstructural changes of both QCFs and their composites were characterized by the X-ray diffraction method. The stacking size and the crystallinity of the QCFs increased with the increasing heat treatment temperature (HTT). The crystallinity of the PAN matrix in a composite was also affected by various QCFs. DSC data indicated that thermal reaction mechanism of the composite could be altered due to the interaction between the fiber and the matrix. DMTA studies showed that good adhesion existed at the interface of the QCF-reinforced composites containing lower HTT fibers. The modulus magnitudes of QCFs and their ...

1994-12-31

229

Study on the electrochemical properties of MgNi-CuO hydrogen storage composite materials  

Energy Technology Data Exchange (ETDEWEB)

To study the effect of CuO on the electrochemical properties of MgNi alloy, the MgNi-xCuO (x = 3, 5 and 10 wt%) composites were prepared by ball-milling method. The X-ray diffraction (XRD) analysis showed that the structures of the composites were amorphous. The cycle stability of the composites was improved compared to pure MgNi alloy due to the enhancement of the anti-corrosion property in the alkaline electrolyte, and the composite with 5 wt% CuO ball-milled for 15 h exhibited the best performance. Electrochemical impedance spectroscopy (EIS) and potential-step measurements indicated that the electrochemical kinetics of the composites was improved.

2009-07-29

230

Chemical resistance, void content and tensile properties of oil palm/jute fibre reinforced polymer hybrid composites  

British Library Electronic Table of Contents (United Kingdom)

Tri layer hybrid composites of oil palm empty fruit bunches (EFB) and jute fibres was prepared by keeping oil palm EFB as skin material and jute as the core material and vice versa. The chemical resistance, void content and tensile properties of oil palm EFB/Jute composites was investigated with reference to the relative weight of oil palm EFB/Jute, i.e. 4:1, the fibre loading was optimized and different layering pattern were investigated. It is found from the chemical resistance test that all the composites are resistant to various chemicals. It was observed that marked reduction in void content of hybrid composites in different layering pattern. From the different layering pattern, the tensile properties were slightly higher for the composite having jute as skin and oil palm EFB as core ...

2011-01-01

231

The associations between milk production, milk composition and Salmonella in the bulk milk supplies of dairy farms in Ontario.  

UK PubMed Central (United Kingdom)

The purpose of this study was to assess changes in dairy herd milk production and milk composition associated with changes in Salmonella contamination of bulk milk on dairy farms in southwestern Ontario....Full Text Available

1989-04-01

232

Studies on Poly(propylene fumarate-co-caprolactone diol) Thermoset Composites towards the Development of Biodegradable Bone Fixation Devices  

UK PubMed Central (United Kingdom)

The effect of reinforcement in the cross-linked poly(propylene fumarate-co-caprolactone diol) thermoset composites based on Kevlar fibres and hydroxyapatite was studied. Cross-linked poly(propylene...Full Text Available

2009-01-01

233

Regional Muscle and Whole-Body Composition Factors Related to Mobility in Older Individuals: A Review  

UK PubMed Central (United Kingdom)

ABSTRACTPurpose: To describe previously reported locomotor muscle and whole-body composition factors related to mobility in older individuals.Methods:...Full Text Available

2009-01-01

234

Properties of superconducting Cu-rich composites containing V_3Si or V_3Ga  

International Nuclear Information System (INIS)

Superconducting Cu-rich composites containing the A-15 compounds V_3Si or V_3Ga were made by the ''Tsuei'' process (melting into ingots followed by cold working and heat treatment). Superconducting transition temperatures of the composites were measured. X-ray diffraction analyses were performed. Microstructures were studied using both the optical metallograph and the scanning electron microscope. For some composites containing V_3Ga, the critical current densities as functions of transverse magnetic field up to 60 kG, and as functions of temperature from 4.2 to 12"0K were measured. It was found that the Tsuei process does not work for the composites containing V_3Si, but works satisfactorily for V_3Ga; reasons are discussed. Relations between measured properties and various metallurgical factors such as alloy compositions, cross-section reduction ratios, and heat treatment are ...

235

Properties of cellulose solutions in methylmorpholine N-oxide containing montmorillonite nanoparticles and of composite films thereof  

British Library Electronic Table of Contents (United Kingdom)

Rheological properties of moderately concentrated solutions of cellulose in methylmorpholine N-oxide-dimethylformamide mixtures containing hydrophilic montmorillonite nanoparticles were studied. Film composite materials were prepared, and their physicomechanical properties and structural organization were studied.

2011-01-01

236

Preparation and biological properties of a novel composite scaffold of nano-hydroxyapatite/chitosan/carboxymethyl cellulose for bone tissue engineering  

UK PubMed Central (United Kingdom)

In this study, we report the physico-chemical and biological properties of a novel biodegradable composite scaffold made of nano-hydroxyapatite and natural derived polymers of chitosan and carboxymethyl...Full Text Available

237

Polyolefin composition  

Energy Technology Data Exchange (ETDEWEB)

A polyolefin composition is described comprising: 100 parts by weight of polyolefin, not less than 0.5 part by weight of a polyamide selected from the group consisting of nylon 6 and nylon 66, and from 3 to 30 percent by weight of a novolak based on the weight of the polyamide.

1986-07-15

238

Method and composition for acidizing subterranean formations  

Energy Technology Data Exchange (ETDEWEB)

The present invention relates to a method of acidizing a subterranean formation or well bore employing an acidic solution containing a corrosion inhibitor composition comprising an inhibiting effective amount of an acetylenic alcohol, a quaternary ammonium compound, an aromatic hydrocarbon and an antimony compound.

1985-02-12

239

Factors influencing the microstructural development of Ca -#alpha#-sialon exhibiting elongated grains  

International Nuclear Information System (INIS)

Ca #alpha#-sialon is a high hardness material that exhibits in-situ growth of elongated grains during pressureless sintering. This potentially gives the material very good fracture toughness. This paper examined the effects of a number of variables on microstructural development during sintering. The effect of composition was investigated by studying seven different compositions. Densification was seen to be hindered in compositions that produced only small quantities of liquid phase during sintering. Elongated #alpha#-sialon was observed in all the compositions. It was in combination with equiaxed #alpha#--sialon in low liquid compositions, but only elongated #alpha#-sialon was present in the liquid rich compositions. The effects of using P-Si_3N_4 instead of #alpha#-Si_3N_4 starting powders were also examined. Compositions using only ...

240

Ethoxylated Bisphenol Dimethacrylate-based Amorphous Calcium Phosphate Composites  

UK PubMed Central (United Kingdom)

Improving the anti-demineralizing/remineralizing and mechanical properties of amorphous calcium phosphate (ACP) composites has been the focus of our recent research. In this study, an ethoxylated...Full Text Available

2006-01-01

241

Effects of Manufacturing Defects and Scaling on Glass Fiber Composite Sandwich Panels in General Aviation Aircraft Structures.  

Science.gov (United States)

This report documents the collaborative effort between the United States and Canada to investigate the impact of process-induced defects on strength and stiffness under static and fatigue loading and for low-cost composite aircraft structures, in particul...

2009-01-01

242

Effects of Collaborative Group Composition and Inquiry Instruction on Reasoning Gains and Achievement in Undergraduate Biology  

UK PubMed Central (United Kingdom)

This study compared the effectiveness of collaborative group composition and instructional method on reasoning gains and achievement in college biology. Based on initial student reasoning ability (i.e.,...Full Text Available

2011-03-01

243

Determination of Thermal Properties and Morphology of Eucalyptus Wood Residue Filled High Density Polyethylene Composites  

UK PubMed Central (United Kingdom)

Thermal behaviors of eucalyptus wood residue (EWR) filled recycled high density polyethylene (HDPE) composites have been measured applying the thermogravimetric analysis (TGA) and differential scanning...Full Text Available

244

Design of Composite Structures for Reliability and Damage Tolerance.  

Science.gov (United States)

A summary of research conducted during the first year is presented. The research objectives were sought by conducting two tasks: (1) investigation of probabilistic design techniques for reliability-based design of composite sandwich panels, and (2) examin...

1999-01-01

245

Current developments in wood-polymer composites  

International Nuclear Information System (INIS)

This investigation clearly demonstrates that through partial impregnation techniques wood-polymer composites can be formed from the Pinus species grown in South Africa with a considerable saving in monomer costs without sacrificing the important physical properties of these materials.

1976-06-17

246

Biogeochemistry and Community Composition of Iron- and Sulfur-Precipitating Microbial Mats at the Chefren Mud Volcano (Nile Deep Sea Fan, Eastern Mediterranean)?  

UK PubMed Central (United Kingdom)

In this study we determined the composition and biogeochemistry of novel, brightly colored, white and orange microbial mats at the surface of a brine seep at the outer rim of the Chefren mud volcano....Full Text Available

2008-05-01

247

BIOASSAY AND CHEMICAL ANALYSIS FOR HAZARDOUS MATERIALS IN RESIDUAL OILS. VOLUME 2. APPENDICES  

Science.gov (United States)

The report gives results of an examination, including mutagenic screening, of the chemical composition of residual fuel oils and their column chromatography pre-fractions. A degree of correlation between composition and mutagenicity has been achieved. Radionuclide data has been o...

248

A field study on the effects of dietary monensin on milk production and milk composition in dairy cows  

UK PubMed Central (United Kingdom)

The objectives of this study were to quantify the effect of 16 ppm of dietary monensin on milk production and composition of dairy cows, and to investigate factors having a potential impact on this...Full Text Available

2010-04-01

249

Wood-plastic composites with high toughness and dimensional stability  

International Nuclear Information System (INIS)

Using acrylic-group containing isocyanates together with methyl methacrylate as impregnating mixture and gamma rays for curing wood-plastic composites have been produced, which show high-dimensional stability and toughness (low brittleness) compared to commonly used wood-plastics. The syntheses of proper acrylic-group containing isocyanates are as well described as the properties of the produced composites, made from maple wood. Also the direct use of the initial compounds, necessary for the syntheses, resulted in products of similar properties. These wood-plastic composites are to be suggested for the production of high-class products, e.g. wood-wind instruments. (author).

1982-10-01

251

The effect of ductile connectors on the behaviour of timber-concrete composite beams  

British Library Electronic Table of Contents (United Kingdom)

The load-carrying capacity and ultimate deformation capacity of timber-concrete composite systems can be significantly influenced by the ductility of the connection between the two materials. The use of more ductile connections can increase the load-carrying capacity of the composite system as well as its ultimate deformation capacity. In this work, the potential increase that might be expected for these two parameters due to the use of ductile connections will be assessed through numerical simulations, taking the non-linear behaviour of the connections into account. Furthermore, the connection ductility required to achieve the maximum load capacity depends on the mechanical properties of the connection as well as on the geometric and mechanical properties of the composite system. There ar...

2011-01-01

252

The asymmetry of the dimension 2 gluon condensate: the zero temperature case  

CERN Document Server

We provide an algebraic study of the local composite operators A_\\mu A_\

2009-01-01

253

The Influence of Timber Harvest on the Distribution of Exotic Riparian  

Science.gov (United States)

... the Redwood Creek basin in north coastal California, timber harvest and associated streamside landsliding altered the composition ... ...

254

Surface Crystallization and Composition of Spinel and Acmite in High-Level Waste Glass  

Science.gov (United States)

Surface crystallization and surface-to-bulk ratio in high-level waste glasses.

2000-07-10

255

Study of the formation of polyethylene composites and lignocellulose materials by means of irradiation and extrusion  

International Nuclear Information System (INIS)

One of the greatest opportunities for using of biomass as a precursor in the production of polymeric materials is the lignocellulose composites that can combine high performance with low costs. This work is a initial study on the production of a lignocellulose reinforced polyethylene composite. A compatibilization made by a induced gamma radiation grafting reaction was used to increase the adhesion between the matrix and the reinforced or filled fibers. The lignocellulose materials were exposed to gamma radiation in order to promote a molecular degradation and increase its reactivity. The polymer, the lignocellulose material and the compatibilization were processed by extrusion and the composite produced by this process were characterized by mechanical tests. (author)

2000-10-05

257

Structural Stability of a Joined-Wing Sensorcraft  

Science.gov (United States)

... core section of the composite sandwich panels (Figure 5). Table 6 shows the properties that buckled as well as their initial ...

2007-06-01

258

Sound absorption of tropical woods and their radiation-induced composites  

International Nuclear Information System (INIS)

This is a preliminary study on the sound absorption properties of two tropical hardwoods, Light Red Meranti and Ramin, and their wood-polymer composites. Sound absorption is measured using a standing wave apparatus. The samples are of one thickness (7 mm) and cut longitudinally. Wood-polymer composites are made by impregnating the samples with methyl methacrylate which is polymerized in situ through #gamma#-irradiation. Both woods and their composites are better sound absorbers at higher sound frequencies. With partial impregnation, the absorption coefficients are improved upon particularly in the region between 1-3 kHz. (author).

1988-01-01

259

Smoke Compositions Based on Phosphorus  

Science.gov (United States)

... Both magnesium and aluminium phosphides are therefore potentially more efficient than either calcium or sodium phosphide. ...

1958-03-01

260

Self-Propagating High-Temperature Synthesis Technologies  

International Science & Technology Center (ISTC)

Development of SHS-technologies for SiC, Si3N4 and Ceramic Composites on Their Basis from Rocks

261

Properties of composite materials on the base of radiation-hardening binders and metal powders  

International Nuclear Information System (INIS)

Compositions (oligomers with suitable properties and Al, Fe, Cu, Ta, W powders) were hardured by the flux of accelerated electrons at 10 mA beam current and 1.5 MeV energy. Dielectric and mechanical properties of metal-filled polymeric compositions as well as their radioply sicl properties in SHF-range are studied. It is shown that the produced compositions belong tot he absorbing protective materials in which the protection effect is mainly achieved through the absorption losses. 6 refs.; 3 tabs.

262

Proceedings of ARO Workshop Biostructures as Composite ...  

Science.gov (United States)

... interactive surfaces and interfaces, and 3) the more complex a ... carbonate or calcium phosphate with a thin interface ... diameter) for nerve prosthesis. ...

1990-03-01

263

OPTIMIZATION OF EDDY CURRENT PROBES FOR NDT OF ...  

Science.gov (United States)

... Accession Number : ADD321199. Title : OPTIMIZATION OF EDDY CURRENT PROBES FOR NDT OF CARBON FIBER COMPOSITES. ...

1985-04-01

264

Moisture Ingression In Honeycomb Core Sandwich Panels: Directional Aspects  

Science.gov (United States)

Moisture ingression was studied in several composite sandwich panels.No observable ingression was

1997-01-01

265

Modeling Blast and High-Velocity Impact of Composite Sandwich Panels  

Science.gov (United States)

Analytical models for predicting the deformation and failure of composite sandwich panels subjected to blast and projectile impact loading are presented in this paper. The analytical predictions of the transient deformations and damage initiation in the composite sandwich panels were compared with finite element solutions using ABAQUS Explicit. For the blast model, the predicted transient deformation of the sandwich panel was within 7%of FEA results, while the predicted damage initiation using Hashin's composite failure criteria was about 15%higher than FEA results in most cases. For the high velocity impact model, the predicted transient deformations were within 20%of FEA results.

2009-01-01

266

MATHEMATICS AND DATA PROCESSING  

Science.gov (United States)

... The task consisted of determination of the most economical composition of the charge of the cupola furnace of the foundry. 21s was no simple task. ...

1963-04-17

267

Long-term hygrothermal effects on damage tolerance of hybrid composite sandwich panels  

Science.gov (United States)

A sandwich construction, composed of hybrid carbon-glass fiber-reinforced plastic skins and a

1995-01-01

268

Heat storage composition  

Energy Technology Data Exchange (ETDEWEB)

A heat storage compostion comprises sodium sulfate decahydrate as main component, a supercooling inhibitor, and a solid-liquid separation inhibitor. The composition is characterized in that hydraulic calcium sulfate and/or calcium sulfate dihydrate is contained as the solid-liquid separation inhibitor in an amount of 2-15 wt% base on the whole weight of the composition, whereby the solid-liquid separation, i.e. the sedimentation of the anhydrous sodium sulfate during the phase transition, is effectively prevented and the long-term stability is improved. The long-term stabilty of the composition can be more improved by addition of a silcia series of thickener.

1987-05-05

276

Consolidation behavior of Cu- and Ni-based bulk metallic glass composites  

Energy Technology Data Exchange (ETDEWEB)

The Cu- and Ni-based bulk metallic glass matrix composites were fabricated by spark plasma sintering of a mixture of gas-atomized metallic glass powders and ductile brass powders. The brass powders added for the enhancement of plasticity are well distributed in the matrix after consolidation. The matrix of the composite materials remains as a fully amorphous phase after consolidation process. With increasing the brass content, the level of plasticity strain increased, although the level of strength decreased. The successful consolidation of metallic glass matrix composite with high density was attributed to viscous flow in the supercooled liquid state during spark plasma sintering.

2007-05-31

277

Compressive and Shear Buckling Analysis of Metal Matrix ...  

Science.gov (United States)

... Title : Compressive and Shear Buckling Analysis of Metal Matrix Composite Sandwich Panels Under Different Thermal Environments. ...

278

Carbon fiber/epoxy matrix composite springs as self-centering supports: manufacture and evaluation  

Energy Technology Data Exchange (ETDEWEB)

A variety of engineering and experimental applications require primary support structures which are self-centering. High mechanical strength, low-density, carbon fiber/epoxy matrix composite springs are used in unique planar, cylindrical, conical, and spherical configurations to self-center components. The sinusoidal and triangular-shaped composite springs are readily manufactured and assembled into component hardware. Design considerations, flexural strength properties, load bearing and centering data plus procedures for the manufacture of composite springs are presented.

1984-01-01

279

Annual Report  

Science.gov (United States)

... energy absorption characteristics of composite sandwich panels, thermoplastic energy-absorbing subfloor structures, and shoulder belt pre- tensioners. ...

280

Abstracts by Mission Directorate - NASA  

Science.gov (United States)

A new high capacity anode composite based on mesoporous silicon is proposed. By virtue of a structure that resembles a pseudo one-dimensional phase, ...

281

A comparative study of the fatty acid composition of prochloron lipids  

Science.gov (United States)

The chemical analysis of lipids of Prochloron isolated from several hosts is discussed. The object

1983-01-01

282

Rhipicephalus sanguineus: vector of a new spotted fever group rickettsia in the United States.  

Science.gov (United States)

A rickettsia related to but distinct from the spotted fever agent, Rickettsia rickettsii, has been detected in 167 (18.9%) of 884 Rhipicephalus sanguineus taken off dogs in central and northern Mississippi. The organisms could readily be isolated in male meadow voles (Microtus pennsylvanicus), where it produced massive infections in the tissues of tunica vaginalis. It was practically nonpathogenic for male guinea pigs, although inoculation of these animals with infected tunica vaginalis of voles afforded in 30 of 38 instances solid immunity to challenge with virulent R. rickettsii. The Rhipicephalus rickettsia grew well in monolayers of chicken embryo fibroblast, Vero, mouse L, and HeLa cells. Cytopathogenic effects were minimal unless large concentrations of rickettsiae were used as inocula. It also could be established in embryonated hen eggs but only after injection of massive doses of L cell-propagated organisms. Serological tests (complement fixation, microagglutination and/or ...

1975-07-01

283

Protective efficiency of dendrosomes as novel nano-sized adjuvants for DNA vaccination against birch pollen allergy  

British Library Electronic Table of Contents (United Kingdom)

We evaluated the use of a novel gene porter (Den123-a nontoxic self-assembled dendritic spheroidal nanoparticle made of biodegradable monomers), aiming to enhance and improve the desired immune response in protection from allergy. Footpad DNA immunization in Balb/c mice was done three times using the Bet v 1a gene with or without Den123 with 2-week intervals followed by sensitization with rBetv1 (5mg) in alum twice in a weekly interval. Different doses of pCMV-Betv1 were used (10mg and 100mg). The protective role of different formulations was evaluated by measuring the IgG1, IgG2a and IgE antibody production, cytokine release of isolated splenocytes and b-hexosaminidase release from the RBL cells. Higher and increasing ratios of IgG2a/IgG1 were seen in mice which received plasmids in combi...

2006-01-01

284

Investigation of xenotropic murine leukemia virus-related virus (XMRV) in human and other cell lines.  

Science.gov (United States)

Xenotropic murine leukemia virus-related virus (XMRV) was discovered in human prostate tumors and later in some chronic fatigue syndrome (CFS) patients. However, subsequent studies have identified various sources of potential contamination with XMRV and other murine leukemia virus (MLV)-related sequences in test samples. Biological and nucleotide sequence analysis indicates that XMRV is distinct from known xenotropic MLVs and has a broad host range and cell tropism including human cells. Therefore, it is prudent to minimize the risk of human exposure to infection by evaluating XMRV contamination in cell lines handled in laboratory research and particularly those used in the manufacture of biological products. Nested DNA PCR assays were optimized for investigating XMRV gag and env sequences in various cell lines, which included MRC-5, Vero, HEK-293, MDCK, HeLa, and A549, that may be used in the development of some vaccines and other cell lines broadly used in ...

2011-10-11

285

Hepatitis B immunization coverage and risk behaviour among Danish travellers Are immunization strategies based on single journey itineraries rational?  

DEFF Research Database (Denmark)

OBJECTIVES: The authors examine the rationale and efficacy of pre-travel hepatitis B immunization strategies based on itinerary and presumed on-travel risk behaviour. METHODS: A large survey among 26,640 Danes survey provided data on journey lengths and destinations, immunization coverage, risk behaviour and knowledge. RESULTS: The estimated cumulative lifetime stay in endemic areas outside Europe is 4.3 months. The majority of risk situations are involuntary and unforeseeable. The majority of risk situations occur on short-term journeys. 5% nonimmune and 5% short-term travellers experienced at least one risk situation such as injections/operations/tattoos on their journey. The level of knowledge of hepatitis A and B is low. CONCLUSIONS: The rationale and efficacy of current immunization strategies are challenged. Based on the results presented here and the availability of vaccines with long-lasting coverage, the authors find that recommendations of immunization ...

2009-01-01

286

GAMMA GLOBULIN METABOLISM IN RABBITS DURING THE ANAMNESTIC RESPONSE.  

Science.gov (United States)

1. Gamma globulin metabolism and distribution were studied employing rabbit gamma globulin (RGG)I(131) 24 times in 13 control rabbits. Similar studies were performed before and during the ananmestic response in 4 rabbits previously sensitized with a polyvalent pneumococcal vaccine. 2. During the ananmestic response, gamma-globulin levels increased from 1.0 to 6.0 gm/100 ml, and the gamma-globulin pool increased from 0.7 to 4.7 gm/kg. There was no change in the intravascular-extravascular partition of gamma globulin. 3. Gamma globulin degradation increased from 0.06 to 0.33 gm/kg/day during the 28 days of the immunization period while gamma globulin synthesis increased even further to average 0.47 gm/kg/day. Following the attainment of elevated gamma globulin levels the fractional rate of RGG-I(131) turnover increased from 8.0 to 12.5 per cent/day. 4. No differences were noted in the metabolism of homologous or autologous gamma globulin regardless of the allotypic ...

1964-04-01

287

Concise review: expanding roles for hematopoietic cellular therapy and the blood transfusion services.  

Science.gov (United States)

Hematopoietic stem cells (HSCs) have remained at the forefront of stem cell research for the past 50 years, since the therapeutic potential of bone marrow transplantation was realized. Uniquely, among stem and progenitor cells, research progress has been made in parallel between the laboratory benchtop and hospital bedside during this period. Integral to this work has been the role of the transfusion medicine services in the collection, storage, and processing of HSCs. The next decade promises to bring further developments: with new fields of cellular therapies, stem cell vaccination, and stem cell drug testing opening up. This article summarizes exciting areas of research concerning the behavior and potential clinical applications of HSCs. For the purposes of clarity, we describe in turn the trafficking and transfer of HSCs; ex vivo expansion of HSC units from different sources; and finally, applications of specifically selected subsets of hematopoietic cells and ...

2011-09-01

288

Biotechnology developments in the livestock sector in developing countries.  

Science.gov (United States)

Global meat and milk consumption is exponentially increasing due to population growth, urbanization and changes in lifestyle in the developing world. This is an excellent opportunity for developing countries to improve the livestock sector by using technological advances. Biotechnology is one of the avenues for improved production in the "Livestock revolution". Biotechnology developments applied to livestock health, nutrition, breeding and reproduction are improving with a reasonable pace in developing countries. Simple bio-techniques such as artificial insemination have been well implemented in many parts of the developing world. However, advanced technologies including transgenic plant vaccines, marker assisted selection, solid state fermentation for the production of fibrolytic enzymes, transgenic fodders, embryo transfer and animal cloning are confined largely to research organizations. Some developing countries such as Taiwan, China and Brazil have considered ...

2010-01-01

289

An adjuvant autologous therapeutic vaccine (HSPPC-96; vitespen) versus observation alone for patients at high risk of recurrence after nephrectomy for renal cell carcinoma: a multicentre, open-label, randomised phase III trial  

British Library Electronic Table of Contents (United Kingdom)

Summary Background Treatment of localised renal cell carcinoma consists of partial or radical nephrectomy. A substantial proportion of patients are at risk for recurrence because no effective adjuvant therapy exists. We investigated the use of an autologous, tumour-derived heat-shock protein (glycoprotein 96)-peptide complex (HSPPC-96; vitespen) as adjuvant treatment in patients at high risk of recurrence after resection of locally advanced renal cell carcinoma. Methods In this open-label trial, patients were randomly assigned to receive either vitespen (n=409) or observation alone (n=409) after nephrectomy. Randomisation was done in a one to one ratio by a computer-generated pseudo-random number generator, with a block size of four, and was stratified by performance score, lymph node stat...

2008-01-01

290

Supersonic flutter of composite sandwich panels  

Science.gov (United States)

A flutter-motion equation is presently derived for a 2D composite sandwich panel considering the total lateral displacement of the plate as the sum of the displacement due to bending of the plate, and that which is due to shear deformation at the core. The effects of core thickness and stacking sequence of the faces on the flutter boundary of the plate are discussed; it is shown that the sandwich panel greatly improves the flutter boundary over that of a composite laminate panel, provided it has sufficient core thickness.

1992-12-01

291

Piezoelectrics based on a hybrid of piezoelectric matrix nano- and microcomposites  

British Library Electronic Table of Contents (United Kingdom)

The physics and technology of a new class of efficient composite piezoelectrics are described. This material combines nanostructured and micropiezoelectric matrix composites. They consist of a polymer matrix, an insulating nanodimensional phase, and a microdimensional piezoelectric phase. It is shown that the nanostructuring of the near-surface region of polymer-PZT piezoelectric composites greatly improves their piezoelectric, mechanical, and electromechanical characteristics. A plausible mechanism underlying this effect is suggested.

2011-01-01

292

Kinetic dialysis as a method for determining mixed micelle composition  

Energy Technology Data Exchange (ETDEWEB)

A new method for the determination of the cmc using a dialysis technique which allows monometric species to diffuse through but no micelles has been applied for determining the mixed micelle composition. The method is based on determining the amount of surfactant that diffuses through at two different times which allows for the calculation of the cmc by use of the appropriate equation. This method requires the preparation of only one concentration of solution and lends itself particularly well to the determination of the composition of mixed micelles. (orig.)

1982-02-16

293

Investigation of morphology and chemical composition of self-organized semiconductor quantum dots and wires by X-ray scattering  

International Nuclear Information System (INIS)

X-ray scattering methods suitable for the investigation of the morphology and chemical composition of self-organized quantum dots and quantum wires are reviewed. Their application is demonstrated in experimental examples showing that a combination of small angle X-ray scattering with high-resolution X-ray diffraction can reveal both the shape and the chemical composition of the self-organized objects. (author)

2001-09-23

294

Electron-beam cladding of wear-resistant composite coatings on the base of titanium carbide  

International Nuclear Information System (INIS)

The structure and properties of composite powder coatings on the base of titanium carbide are studied. It is shown the electron-beam welding deposition of powders on the base of nickel and titanium carbide allows to produce of high-quality wear-resistant coatings which superior in density and hardness compared with sputtered ones. Changes of hardening phase volume percentage as well as composition of metal matrix make possible to control coatings hardness

295

Effect of heat treatment on the properties of Metglas foils, and laminated magnetoelectric composites made thereof  

British Library Electronic Table of Contents (United Kingdom)

Annealing of magnetostrictive Metglas foils, subsequently incorporated into laminated Metglas/Pb(Zr, Ti)O3 magnetoelectric (ME) composites, is shown to result in improved magnetic properties, as well as ME coefficients. Annealing of the foils at 350 ?C resulted in partial crystallization, without oxidation or magnetic cluster formation that would reduce the magnetization. Laminate composites made with these annealed Metglas foils had improved ME coefficients.

2011-01-01

296

Depth of origin of the gas content in thermal waters  

Energy Technology Data Exchange (ETDEWEB)

The gas composition of recent thermal waters is in perfect conformity with their geologic-tectonic positions. The composition of gas-liquid inclusions in the basic-hyperbasic xenoliths of basaltoid lavas depends on the depth from which xenoliths are supplied. (The depth is determined by using the methods of geological thermobarometers). By comparing available data the conclusion was drawn that the gas compositions of thermal waters reflect the depth of generation of deep fluid which heats them and depends on the penetration depth of the fluid-conducting fissure zones.

1980-01-01

297

Characterization of wood polymer composites (WPC) as an engineering material  

International Nuclear Information System (INIS)

Radiation processed wood-polymer composites (WPC) can replace conventional wood in many industrial applications. However, for proper utilization of the composites, adequate testing and evaluation programmes are essential. The paper briefly describes the development of WPC at the Bhabha Atomic Research Centre, Bombay, and the evaluation of WPC for various applications in greater details. The various mechanical properties and their significance in overall performance of WPC are also discussed. (author).

1980-08-01

298

What is the technical and environmental interest in reusing a recycled polypropylene-hemp fibre composite?  

British Library Electronic Table of Contents (United Kingdom)

The integration of the environmental problem in the design of industrial products leads us to incorporate vegetal fibres and recycled polymers into composite materials. The aim of this work is to study the behaviour and the environmental interest of a recycled PP/hemp fibre after several injection cycles. The mechanical and rheological behaviour of recycled PP/hemp composite was first studied by using tensile, dynamical mechanic analysis and rheological measurements. Then, to better understand the influence of the recycling, a morphology study was carried out on composites by using optical and electron microscopy. Finally, we investigated the environmental advantages of our composite thanks to a simplified environmental assessment. Our results highlighted the environmental interest of usin...

2011-01-01

299

Tris(2,2prime-bipyridyl)ruthenium(II) electrogenerated chemiluminescence sensor based on carbon nantube dispersed in sol-gel-derived titania-Nafion composite films  

British Library Electronic Table of Contents (United Kingdom)

A highly sensitive and stable tris(2,2prime-bipyridyl)ruthenium(II) (Ru(bpy)32+) electrogenerated chemiluminescence (ECL) sensor was developed based on carbon nanotube (CNT) dispersed in mesoporous composite films of sol-gel titania and perfluorosulfonated ionomer (Nafion). Single-wall (SWCNT) and multi-wall carbon nanotubes (MWCNT) can be easily dispersed in the titania-Nafion composite solution. The hydrophobic CNT in the titania-Nafion composite films coated on a glassy carbon electrode certainly increased the amount of Ru(bpy)32+ immobilized in the ECL sensor by adsorption of Ru(bpy)32+ onto CNT surface, the electrocatalytic activity towards the oxidation of hydrophobic analytes, and the electronic conductivity of the composite films. Therefore, the present ECL sensor based on the CNT-...

2006-01-01

300

Study of age hardening behavior of Al-4.5wt%Cu/zircon sand composite in different quenching media - A comparative study  

British Library Electronic Table of Contents (United Kingdom)

The age hardening behavior of Al-4.5%Cu alloy composite reinforced with zircon sand particulates and produced by stir casting route has been investigated in different quenching media viz, water, oil, and salt brine solution (7wt%). Optical microscopy of the as cast alloy composite indicates that the matrix of the composite has the cellular structure. Copper rich CuAl2 precipitates have been found near particle matrix interface. The results of ageing demonstrate that the microhardness of age hardenable Al-Cu based alloy composites depend on the quenching medium in which they are heat treated. Salt brine quenching is faster as compared to water and oil, even if higher strength is obtained but cannot be used for complex shapes and thin sections where oil quenching is the alternative due to mi...

2009-01-01

301

Some properties of composite panels made from wood flour and recycled polyethylene.  

Science.gov (United States)

This study investigated the effect of board type (unmodified vs. MAPE modified) on the surface quality and thickness swelling-water absorption properties of recycled high density polyethylene (HDPE) based wood plastic composites. Additionally, two commercially available coatings (cellulosic coating and polyurethane lacquer coating) were also applied to composite surfaces and their adhesion strength, abrasion and scratch resistance, and gloss values were determined. This study showed that modification of the composites with MAPE coupling agent increased the surface smoothness and reduced the water absorption and thickness swelling of the panels. Abrasion resistance of the composites was also improved through MAPE modification. Regardless of board type, higher scratch resistance and gloss values were observed for polyurethane lacquer coated samples compared to those of cellulosic varnish coated ones. ...

2008-12-10

302

Quantitative measurement of elements in a composite, using multienergy gamma-rays  

International Nuclear Information System (INIS)

This study is an attempt to measure the quantities of elements in a composite by irradiating that composite with #gamma#-rays of various energies and detecting the transmitted radiation through the composite. A previous knowledge of the number of the elements and their attenuation coefficients is required. The quantities are calculated by solving the matrix of a linear system of equations. A computer program was developed to select the best combinations of the available energies. Five criteria were established to determine these energy combinations: (i) the determinant of the attenuation coefficient matrix; (ii) the condition number, (iii) the number of times the solution of the matrix leads to acceptable results; (iv) the indicator, (a new concept); (v) the standard deviations of the results. The intended application of this technique in medicine is to measure the bone mineral content of the skeleton. An examination of the ...

303

Process for repairing a cryogenic heat exchanger  

International Nuclear Information System (INIS)

The patent describes a method for repairing leakage-causing cracks and fissures in a cryogenic heat exchanger. It comprises: reducing the interior pressure of the heat exchanger to a level which does not exceed the external pressure upon the hear exchanger while maintaining the temperature of the heat exchanger at a low level relative to the ambient external temperature; applying a curable liquid filler composition to the surface of the heat exchanger proximal the leakage site for seepage into the cracks and fissures located at the leakage. The composition upon a relatively short period of cure at low temperature forming a solid material which fills the cracks and fissures; curing the filler composition; and, applying a sealant composition to the surface of the heat exchanger at the filled leakage site. The sealant composition having long-term sealing performance under cyrogenic ...

1987-10-13

304

Polyester and multiwalled carbon nanotube composites: characterization, electrical conductivity and antibacterial activity  

British Library Electronic Table of Contents (United Kingdom)

Abstract Poly(butylene terephthalate) (PBT) composites containing multiwalled carbon nanotubes (MWCNTs) were prepared using a melt-blending process and used to examine the effects on the composite structure and properties of replacing PBT with acrylic acid-grafted PBT (PBT-g-AA). PBT-g-AA and multihydroxyl-functionalized MWCNTs (MWCNTs-OH) were used to improve the compatibility and dispersibility of the MWCNTs within the PBT matrix. The composites were characterized morphologically using transmission electron microscopy, and chemically using Fourier transform infrared, solid-state 13C NMR and UV-visible absorption spectroscopy. The antibacterial and electrical conductivity properties of the composites were also evaluated. MWCNTs or MWCNTs-OH enhanced the antibacterial activity and electric...

2011-01-01

305

Particulate composites in the TiC-TiYTZP system  

International Nuclear Information System (INIS)

Twelve powders of TiO_2-Y_2O_3-ZrO_2 solid solution of the methodically changed composition were prepared by a coprecipitation-calcination technique. After mixing with phenol-formaldehyde resin, the powders were calcinated for 2 hours at 1200"oC in vacuum. The resultant composite powders contained TiC and non-reacted carbon. Green compacts were sintered in vacuum at 1500"oC for 2 hours. A temperature increase was stopped at 1200"oC to react remains of carbon. There were two carbides in the composites TiC and ZrC. TiC non-stoichiometry depended on carbon content in the system. Phase composition of the depended on of titania and yttria in zirconia solid solution. The majority of the samples showed two tetragonal zirconia phases differing in lattice parameter and tetragonality. (author)

2004-09-12

306

Mechanical properties of surface composite particles coated with finer particles; Hyomen hifukugata fukuto biryushiso no rikigaku tokusei  

Energy Technology Data Exchange (ETDEWEB)

The effect of the coated composite surface of particles on the mechanical properties of the powder bed was investigated. Polyethylene-silica surface composite powder was prepared at several coating ratios with Hybridizer. Various tests on mechanical properties of the powder bed were carried out with the prepared powder, and the following results were obtained: The ultimate tensile strength depends only on the cohesive force between particles, and the contact probability model of composite particles led to good agreement between the experimental and calculated values. The coefficient of internal friction and cohesive shear strength were influenced due to the interlocking effect of the surface roughness of composite particles. The effects of coating particles became small with dynamic properties like angle of repose. It is possible to control the mechanical properties in a step wise fashion by changing ...

1996-05-10

307

Influence of interphase morphology on adhesion and composite durability in semicrystalline polymer matrix composites  

Energy Technology Data Exchange (ETDEWEB)

The microstructure of the interphase in semicrystalline polymer matrix composites has a dramatic influence on their mechanical properties. Studies have been performed to alter this region and to correlate various interphase morphologies with changes in fiber-matrix adhesion. A reinforced nylon 66 composite, when subjected to specific thermal histories, contains an interphase composed of transcrystallinity. This region has been altered by coating fibers with a diluent, poly(vinyl pyrrolidone), and/or adding the diluent to the matrix material in very small quantities. Interphase morphology was investigated with optical microscopy, and adhesion was measured using a modified fiber pull-out test. It was found that transcrystallinity increases the interfacial shear strength. The effect different interphase morphologies have on the durability of bulk composite samples is currently under investigation.

1996-12-31

308

Effects of carbon fiber surface treatment on the friction and wear behavior of 2D woven carbon fabric/phenolic composites  

British Library Electronic Table of Contents (United Kingdom)

To improve the friction and wear behavior of carbon fabric reinforced polymer composites (CFRP), nano-SiO2 was deposited on the fabric surface. The friction and wear behavior of the resulting composites were investigated on a model ring-on-block test rig. Experimental results revealed that fiber surface treatment contributed to largely improve the tribological properties of the CFRP composites. Scanning electron microscope (SEM) investigation showed that the worn surface of the surface modified CFRP composite was smoother under given load and sliding rate. Field emission scanning electron microscopy (FESEM), FTIR and X-ray photoelectron spectroscopy (XPS) studies of the carbon fiber surface showed that nanostructured Sio2 thin film can be obtained by SiO2 sols deposition, which improved th...

2009-01-01

309

Chemistry and technology of radiation processed composite materials  

International Nuclear Information System (INIS)

Composite materials of synthetics (based on monomers, oligomers and thermoplastics) and of natural polymers (wood and other fibrous cellulosics) prepared by radiation processing, offer valuable structural materials with enhanced coupling forces between the components. The applied polymer chemistry of such composites shows several common features with that of radiation grafting. E.g. the polymerization rate of oligomer-monomer mixtures in wood remains in most cases proportional to the square-root of the initiating dose-rate, just as in the simultaneous grafting, demonstrating that the chain termination kinetics remain regularly bimolecular in the corresponding dose-rate ranges. In the processing experiences of such composites, low dose requirement, easy process-control, and good technical feasibility have been found for composites of wood with oligomer-monomer mixtures, for coconut fibres with ...

1984-10-01

310

Chemistry and technology of radiation processed composite materials  

International Nuclear Information System (INIS)

Composite materials of synthetics (based on monomers, oligomers and thermoplastics) and of natural polymers (wood and other fibrous cellulosics) prepared by radiation processing, offer valuable structural materials with enhanced coupling forces between the components. The applied polymer chemistry of such composites shows several common features with that of radiation grafting, e.g. the polymerization rate of oligomer-monomer mixtures in wood remains in most cases proportional to the square-root of the initiating dose-rate, just as in the simultaneous grafting, demonstrating that the chain termination kinetics remain regularly bimolecular in the corresponding dose-rate ranges. In the processing experiences of such composites, low dose requirement, easy process-control, and good technical feasibility have been found for composites of wood with oligomer-monomer mixtures, for coconut fibres with ...

1984-10-01

311

Wear-resistance of manganese steel surface composites with cast tungsten carbide particles; Wc-W2C ryushi ni yori hyomen fukugokashita mangan ko no tai mamosei  

Energy Technology Data Exchange (ETDEWEB)

To make the surface composites with hard ceramics particles is an effective means for satisfying the request for the wear-resistance of the casting products. Covering casting is a general method for forming the composites by adding the adhesive into ceramics particles. However, due to the using of adhesive, pore and intermediate are easy to generate, and it is one of the reasons making the wear-resistance unstable. In the present study, it is attempted to form the wear-resistant composite layer by dispersing cast tungsten carbide (CTC) particles on the surface of wear-resistant 7 mass% Mn steel without using adhesives. Subsequently, the experiments on the wear-resistance of the obtained surface composites under several wear conditions are carried out. It is revealed by the results thereof that 7 mass% Mn steel surface composites with CTC particles have the wear-resistance which is ...

1995-04-25

312

Spherical nanostructured Si/C composite prepared by spray drying technique for lithium ion batteries anode  

International Nuclear Information System (INIS)

Spherical nanostructured Si/C composite was prepared by spray drying technique, followed by heat treatment, in which nanosized silicon and fine graphite particles were homogeneously embedded in carbon matrix pyrolyzed by phenol formaldehyde resin. Cyclic voltammetry tests showed two pairs of redox peaks corresponding to lithiation and delithiation of Si/C composite. The Si/C composite exhibited a reversible capacity of 635 mAh g"-"1 and good cycle performance used in lithium ion batteries. To improve cycle performance of this Si/C composite further, the carbon-coated Si/C composite was synthesized by the second spray drying and heat treatment processing. The cycle performance of carbon-coated Si/C composite was improved significantly, which was attributed to the formation of stable SEI passivation layers on the outer surface of carbon shell which protected the ...

2006-07-15

313

Morphology and thermal properties of electrospun fatty acids/polyethylene terephthalate composite fibers as novel form-stable phase change materials  

Energy Technology Data Exchange (ETDEWEB)

The ultrafine fibers based on the composites of polyethylene terephthalate (PET) and a series of fatty acids, lauric acid (LA), myristic acid (MA), palmitic acid (PA), and stearic acid (SA), were prepared successfully via electrospinning as form-stable phase change materials (PCMs). The morphology and thermal properties of the composite fibers were studied by field emission scanning electron microscopy (FE-SEM) and differential scanning calorimetry (DSC), respectively. It was found that the average fiber diameter increased generally with the content of fatty acid (LA) in the LA/PET composite fibers. The fibers with the low mass ratio maintained cylindrical shape with smooth surface while the quality became worse when the mass ratio is too high (more than 100/100). Moreover, the latent heat of the composite fibers increased with the increase of LA content and the phase transition temperature of the ...

2008-11-15

314

Lanthanum gallate and ceria composite as electrolyte for solid oxide fuel cells  

International Nuclear Information System (INIS)

The composite of doped lanthanum gallate (La_0_._9Sr_0_._1Ga_0_._8Mg_0_._2O_2_._8_5, LSGM) and doped ceria (Ce_0_._8Sm_0_._2O_1_._9, CSO) was investigated as an electrolyte for solid oxide fuel cell (SOFC). The LSGM-CSO composite was examined by X-ray diffraction (XRD) and impedance spectroscopy. It was found that the sintered LSGM-CSO composite contains mainly fluorite CeO_2 phase and a minority impurity phase, Sm_3Ga_5O_1_2. The LSGM-CSO composite electrolyte shows a small grain boundary response in the impedance spectroscopy as compared to LSGM and CSO pellets. The composite electrolyte exhibits the highest conductivity in the temperature range of 250-600 "oC, compared to LSGM and CSO. The LSGM-CSO composite can be expected to be an attractive intermediate temperature electrolyte material for solid oxide fuel cells.

2010-03-04

315

Fabrication and animal experiment of nanocomposites of hydroxyapatite collagen and polysaccharides  

Energy Technology Data Exchange (ETDEWEB)

Four species of nanocomposites organized by hydroxyapatite (HAp), hyaluronic acid (HyA), chondroitin sulfate (ChS) and type II collagen (Col), i.e. HAp/HyA, HAp/ChS, HAp/HyA/Col and HAp/ChS/Col composites, were synthesized by coprecipitation methods. The composites could retain lots of water: 40%, 32%, 42% and 58% for the HAp/HyA, HAp/ChS, HAp/HyA/Col and HAp/ChS/Col composites, respectively. Transmission electron microscopy observations revealed that the HAp/HyA and HAp/ChS composites consisted of island-like aggregations whose sizes were 300 nm in length and 30 nm in width, and 150 nm in length and 30 nm in width, respectively. In the aggregations, there were many HAp nanocrystals of 20 nm in length, and their c-axes were aligned along the respective polymer molecules through a self-organization process. Animal tests showed that chondrocyte-like cells penetrated into the HAp/ChS/Col ...

2001-07-01

316

Electrochemical hydrogen storage of ball-milled MmMg{sub 12} alloy-Ni composites  

Energy Technology Data Exchange (ETDEWEB)

MmMg{sub 12}-Ni amorphous or nanocrystalline composites (Mm: Ce-rich mischmetal) were prepared through the ball-milling method, and their electrochemical hydrogen storage performance was investigated and compared with that of ball-milled CeMg{sub 12}-Ni composites. It was found that the ball-milled MmMg{sub 12}-Ni composites had larger initial discharge capacities and better high rate dischargeability. Analysis of electrochemical impedance spectra (EIS) shows that the reaction resistance and hydrogen diffusion resistance of the ball-milled MmMg{sub 12}-Ni composites are lower as a result of the decrease in Ce content, and thus can contribute to the larger discharge capacity and better high rate dischargeability. Additionally, the cycle performance of the ball-milled MmMg{sub 12}-Ni composites is better than those of the ball-milled CeMg{sub 12}-Ni composites. ...

2010-04-15

317

Composites from recycled wood and plastics. Report for May 1990-July 1993  

Energy Technology Data Exchange (ETDEWEB)

The ultimate goal of this research was to develop technology to convert recycled wood fiber and plastics into durable products that are recyclable and otherwise environmentally friendly. Two processing technologies were used to prepare wood-plastic composites: air-laying and melt-blending. Research was conducted in (1) developing laboratory methods for converting waste wood, wastepaper, and waste plastics into forms suitable for processing into composites; (2) optimizing laboratory methods for making composite panels from the waste materials; (3) establishing a database on the effects of formulation and bonding agent on physical and mechanical properties of composites; (4) establishing the extent to which the composites can be recycled without unacceptable loss in properties; and (5) reaching out to industry to provide education, to develop applications, and to extend the database. ...

1995-01-01

318

Investigation on corrosion and wear behaviors of nanoparticles reinforced Ni-based composite alloying layer  

Energy Technology Data Exchange (ETDEWEB)

In order to investigate the role of amorphous SiO{sub 2} particles in corrosion and wear resistance of Ni-based metal matrix composite alloying layer, the amorphous nano-SiO{sub 2} particles reinforced Ni-based composite alloying layer has been prepared by double glow plasma alloying on AISI 316L stainless steel surface, where Ni/amorphous nano-SiO{sub 2} was firstly predeposited by brush plating. The composition and microstructure of the nano-SiO{sub 2} particles reinforced Ni-based composite alloying layer were analyzed by using SEM, TEM and XRD. The results indicated that the composite alloying layer consisted of {gamma}-phase and amorphous nano-SiO{sub 2} particles, and under alloying temperature (1000 deg. C) condition, the nano-SiO{sub 2} particles were uniformly distributed in the alloying layer and still kept the amorphous structure. The corrosion resistance of ...

2008-04-30

319

Investigation on corrosion and wear behaviors of nanoparticles reinforced Ni-based composite alloying layer  

International Nuclear Information System (INIS)

In order to investigate the role of amorphous SiO2 particles in corrosion and wear resistance of Ni-based metal matrix composite alloying layer, the amorphous nano-SiO2 particles reinforced Ni-based composite alloying layer has been prepared by double glow plasma alloying on AISI 316L stainless steel surface, where Ni/amorphous nano-SiO2 was firstly predeposited by brush plating. The composition and microstructure of the nano-SiO2 particles reinforced Ni-based composite alloying layer were analyzed by using SEM, TEM and XRD. The results indicated that the composite alloying layer consisted of ?-phase and amorphous nano-SiO2 particles, and under alloying temperature (1000 deg. C) condition, the nano-SiO2 particles were uniformly distributed in the alloying layer and still kept the amorphous structure. The corrosion resistance of composite alloying layer was ...

2008-04-30

320

Wear behavior on advanced structural ceramics: #alpha#-sialon matrix reinforced with #beta#-sialon fibers  

International Nuclear Information System (INIS)

For several decades, ceramic matrix composite have been attracted attention in advanced structural and tribological applications. Advanced structural ceramics are presently used in diverse tribological applications such as tips for ballpoint pens, precision instrument bearings and cutting tools inserts. Design and selection of ceramics for these applications require reliable data on the effects of temperature, load and environment on the tribological behavior of these ceramics. In the present work, #alpha#-sialon matrix composites reinforced with different amounts of #beta#-sialon fibers were produced with the aim of improving their toughness to increase the industrial applications. The wear properties of #alpha#-sialon matrix composites were evaluated by carried out wear tests using a pin-on-disk tribometer under dry conditions. The #alpha#-sialon matrix composites were manufactured by slip casting and ...

2005-08-01

321

Tris(2,2prime-bipyridyl)ruthenium(II) Electrogenerated Chemiluminescence Sensor Based on Sol-Gel-Derived V2O5/Nafion Composite Films  

British Library Electronic Table of Contents (United Kingdom)

Mesoporous V2O5/Nafion composite films have been used for the immobilization of tris(2,2prime-bipyridyl)ruthenium (II) (Ru(bpy)$\\rm{ {_{3}^{2+}}}$) on an electrode surface to yield a solid-state electrogenerated chemiluminescence (ECL) sensor. The electrochemical and ECL behavior of Ru(bpy)$\\rm{ {_{3}^{2+}}}$ ion-exchanged into the composite films has been characterized as a function of the amount of Nafion incorporated into the V2O5/Nafion composite. The composite film with 80% Nafion content has the largest pore diameter (4.19 nm) and yields the maximum ECL response for tripropylamine (TPA) because of the fast diffusion of analyte into the film with large pores. Due to the enlarged pore size and enhanced conductivity of the V2O5/Nafion composite, the present ECL sensor based on the compo...

2006-01-01

322

Technological physics and special materials: wood-plastic composites obtained by radiation polymerization  

International Nuclear Information System (INIS)

General estimates and references are made in connection with the role of technological physics in obtaining materials with specific features. The first part of the paper presents the modification of weak wood essences as well as technological processes at bench-scale and semi industrial scale of wood-plastic composites, under various irradiation conditions. Two technological installations for the fabrication of wood-plastic composites on both scales with technical and practical specifications of their performances are presented. Experimental data for different wood-plastic composite systems using some local wood essences in combination with several polymer and copolymer systems are given. Impregnation and polymerization levels are mentioned for every specific system. The radiation dose rate and integrated dose are given for every experimental polymerization system. The features of the wood-plastic ...

1995-12-02

323

Synthesis and characterization of Al{sub 2}O{sub 3}/ZrO{sub 2}, Al{sub 2}O{sub 3}/TiO{sub 2} and Al{sub 2}O{sub 3}/ZrO{sub 2}/TiO{sub 2} ceramic composite particles prepared by ultrasonic spray pyrolysis  

Energy Technology Data Exchange (ETDEWEB)

Fine ceramic particles of zirconia toughened alumina (ZTA), titania toughened alumina (TTA), and zirconia-titania toughened alumina (ZTTA) have been synthesized by ultrasonic spray pyrolysis (USP) at various temperatures from starting salt solutions of various compositions aiming for the development of catalytic material. These particles were characterized for properties such as shape, size and size distribution, diffraction pattern, and chemical and phase composition of elements by scanning electron microscopy (SEM), particle size analyzer (PSA), x-ray diffraction (XRD), and inductively coupled plasma-atomic emission spectroscopy (ICP-AES). Chemical compositions and sizes of ceramic composites have been controlled by the stoichiometry of salt solutions and the flow rate of spraying solutions. The optimum experimental conditions for the various composite particle synthesis have been ...

2002-08-01

324

Synthesis and characterization of Al_2O_3/ZrO_2, Al_2O_3/TiO_2 and Al_2O_3/ZrO_2/TiO_2 ceramic composite particles prepared by ultrasonic spray pyrolysis  

International Nuclear Information System (INIS)

Fine ceramic particles of zirconia toughened alumina (ZTA), titania toughened alumina (TTA), and zirconia-titania toughened alumina (ZTTA) have been synthesized by ultrasonic spray pyrolysis (USP) at various temperatures from starting salt solutions of various compositions aiming for the development of catalytic material. These particles were characterized for properties such as shape, size and size distribution, diffraction pattern, and chemical and phase composition of elements by scanning electron microscopy (SEM), particle size analyzer (PSA), x-ray diffraction (XRD), and inductively coupled plasma-atomic emission spectroscopy (ICP-AES). Chemical compositions and sizes of ceramic composites have been controlled by the stoichiometry of salt solutions and the flow rate of spraying solutions. The optimum experimental conditions for the various composite particle synthesis have been ...

2002-08-01

325

Study on the correlation between chemical and mineral composition of coal ashes; Sekitanbaibun no kobutsu soseigakuteki kento kagakubutsu sosei to kobutsugakuteki sosei no sokan  

Energy Technology Data Exchange (ETDEWEB)

Coal ash is a substance that has been mixed into minerals in the earth`s crust during their coalification process. Estimation was made on what kinds of mineral composition have been mixed into coals. Noted first was the kinds of compounds contained in the ash, wherein the ratios of mass in the compounds and minerals were correlated, and selection was made on minerals which are thought correlated. The selection criterion was based on minerals containing silica, alumina, iron oxide, lime and magnesium as compounds. Then, a phase equilibrium line diagram was used to estimate compositions and melting points of minerals which are thought to have been produced from these compounds. By comparing the estimation with the measured melting points of the ashes, mineral compositions thought reasonable were all selected. Assumption was possible on minerals that are thought to have been transferred into coal ash. Compound indications of ...

1996-10-28

326

Pre-irradiation technique for processing of oil palm fruit bunch fibers - polypropylene composites  

International Nuclear Information System (INIS)

Researches on oil palm empty fruit bunch (EFB) fibers and thermoplastic composites have been carried out by many workers in the last decade. The main focus was to enhance the properties of the resultant composites in view of the incompatibility of the two components. Thus, efforts have been made to enhance their properties by using coupling agents, treating the fibers and modifying the matrices. In this study, the effects of electron beam (EB) irradiation and some reactive additives (RAs) on the mechanical properties of EFB-PP (polypropylene) composites were evaluated. Different modes of irradiation were investigated. Mono, di and tri functional of monomers of RAs were used. irradiating PP alone, compared to irradiating the EFB fibers or irradiating both components, gave optimum properties for EFB-PP composites. Further, improvements of the properties of the composites were achieved ...

2002-06-25

327

Oil palm empty fruit bunch (OPEFB) fiber reinforced PVC/ENR blend-electron beam irradiation  

Energy Technology Data Exchange (ETDEWEB)

The effect of irradiation on the tensile properties of oil palm empty fruit bunch (OPEFB) fiber reinforced poly(vinyl chloride)/epoxidized natural rubber (PVC/ENR) blends were studied. The composites were prepared by mixing the fiber and the PVC/ENR blend using HAAKE Rheomixer at 150 deg. C. The composites were then irradiated by using a 3.0 MeV electron beam machine at doses ranging from 0 to 100 kGy in air and room temperature. The tensile strength, Young's modulus, elongation at break and gel fraction of the composites were measured. Comparative studies were also made by using poly(methyl acrylate) grafted OPEFB fiber in the similar blend system. An increase in tensile strength, Young's modulus and gel fraction, with a concurrent reduction in the elongation at break (Eb) of the PVC/ENR/OPEFB composites were observed upon electron beam irradiation. Studies revealed that grafting of ...

2007-12-15

328

Ionic conductivity enhancement for lithium solid electrolyte; Lithium ion dodensei kotai denkaishitsu no dodensei kojo kiko no kaimei  

Energy Technology Data Exchange (ETDEWEB)

For the development of high ionic conductive solid electrolyte, LiTi2(PO4)3 (LTP), one of the promising inorganic solid electrolyte, was synthesized to investigate an effect of additional lithium salt on the ion conductivity. Lithium salt added LTP composite electrolyte sintered at 900{degree}C exhibited highest conductivity, which was two order magnitude higher than pure LTP. Effects of lithium salt addition are as follows. Conductivity of the composite electrolyte provided larger sintering temperature dependence than the pure LTP. From X-ray diffraction analysis, structures and compositions were resemble between two composite electrolytes. Byproducts except LTP provided rather low conductivity. It was suggested that melted constitution in the composite can affect the sintering improvement by the additional lithium salt at temperatures over 800 {degree}C. From the observation of ...

1996-08-01

329

High temperature mechanical properties of a {beta}-Si{sub 3}N{sub 4} whisker reinforced aluminium alloy composite produced by squeeze casting  

Energy Technology Data Exchange (ETDEWEB)

The {beta}-Si{sub 3}N{sub 4}w/6061 Al composite was fabricated by the squeeze casting and extruded with the extrusion ratios of 44 and 100 at 773 K. Its tensile strength and superplastic characteristics were investigated and the following results were obtained: (1) the {beta}-Si{sub 3}N{sub 4}w/6061 Al composite exhibits the tensile strengths of about 400 MPa at room temperature and of about 250 MPa at 773 K; (2) the m value of the composite pulled at 818 K is 0.33 in the strain rate range from 0.02 up to 1.0 s{sup {minus}1}; (3) the total elongation of the composite becomes about 173 % at the strain rate of 0.02 s{sup {minus}1} even in the case of the high volume fraction of 0.25; (4) no reaction product on the surface of {beta}-Si{sub 3}N{sub 4} whisker after removing a matrix by etching was detected except AlN; (5) the fracture surface of the composite includes the melt matrix ...

1995-06-01

330

Composition heterogeneity analysis for DUPIC fuel(I) - Statistical analysis  

Energy Technology Data Exchange (ETDEWEB)

The fuel composition heterogeneity effect on reactor performance parameters was assessed by refueling simulations for three DUPIC fuel options of fuel composition heterogeneity control: the fissile content adjustment, the reactivity control by slightly enriched and depleted uranium, and the reactivity control by natural uranium. For each DUPIC fuel option, the simulations were performed using 30 heterogeneous fuel types which were determined by the agglomerative hierarchical clustering method. The heterogeneity effect was considered during the refueling simulation by randomly selecting fuel types for the refueling operation. The refueling simulations of the heterogeneous core have shown that the key performance parameters such as the maximum channel power (MCP), maximum bundle power (MBP), and channel power peaking factor (CPPF) are close to those of the core that has single fuel type. For the three DUPIC fuel options, the uncertainties of MCP, ...

1999-08-01

331

Composition determination of sputter-deposited HgS films by electron microprobe analysis  

Energy Technology Data Exchange (ETDEWEB)

The composition of sputter-deposited HgS films was determined by electron microprobe analysis. From the relative x-ray intensity as a function of film thickness, the depth of the ionizations that produce SK sub(..cap alpha..) and HgM sub(..cap alpha..) was found to be approximately 0.65 ..mu..m at an accelerating voltage of 15 kV. This value agreed well with a value calculated from Castaings' empirical law after absorption correction. The determination of film composition was limited to sufficiently thicker films than this critical value, usually 1 - 2 ..mu..m thick. The relation between the conposition of bulk standard determined by chemical analysis and the x-ray intensity ratio was used for the correction of film composition. The results showed that the crystal structure of HgS films was independent of the composition, i.e., the growth of metastable ..beta..-HgS films was not caused by the ...

1982-01-01

332

Composition determination of sputter-deposited HgS films by electron microprobe analysis  

International Nuclear Information System (INIS)

The composition of sputter-deposited HgS films was determined by electron microprobe analysis. From the relative x-ray intensity as a function of film thickness, the depth of the ionizations that produce SK sub(#alpha#) and HgM sub(#alpha#) was found to be approximately 0.65 #mu#m at an accelerating voltage of 15 kV. This value agreed well with a value calculated from Castaings' empirical law after absorption correction. The determination of film composition was limited to sufficiently thicker films than this critical value, usually 1 - 2 #mu#m thick. The relation between the conposition of bulk standard determined by chemical analysis and the x-ray intensity ratio was used for the correction of film composition. The results showed that the crystal structure of HgS films was independent of the composition, i.e., the growth of metastable #betta#-HgS films was not caused by the nonstoichiometry, and that ...

1982-01-01

333

Wood plastic composite at different urea concentrations  

Energy Technology Data Exchange (ETDEWEB)

Wood plastic composite (WPC) has been prepared with a low grade wood simul (Salmalia malabarica) of Bangladesh under Co-60 gamma irradiation using MMA as the bulk monomer combined with methanol as the swelling solvent at different urea concentrations. Effect of a second solute such as NVP, TPGDA and TMPTA in the impregnating solution is evaluated. NVP appears to be the best co-additive/second solute among all the additives used to yield the composite with the highest polymer loading (PL) and tensile strength (TS) at 0.5% urea concentration. (author).

1995-04-01

334

Wood plastic composite at different urea concentrations  

International Nuclear Information System (INIS)

Wood plastic composite (WPC) has been prepared with a low grade wood simul (Salmalia malabarica) of Bangladesh under Co-60 gamma irradiation using MMA as the bulk monomer combined with methanol as the swelling solvent at different urea concentrations. Effect of a second solute such as NVP, TPGDA and TMPTA in the impregnating solution is evaluated. NVP appears to be the best co-additive/second solute among all the additives used to yield the composite with the highest polymer loading (PL) and tensile strength (TS) at 0.5% urea concentration. (author).

1995-01-01

335

Synergistic yields in the wood plastic composites  

Energy Technology Data Exchange (ETDEWEB)

Wood plastic composites formation has been studied with simul (soft wood, density = 0.4 g/cm{sup 3}) and butylmethacrylate (BA) monomer using 10% methanol as the swelling agent. The effect of additives like sulfuric acid, multifunctional monomers (NVP, TPGDA, TMPTA) and oligomers (PEA, UA and EA) has been investigated using 1-3 Mrad dose at 0.8 Mrad/h. Synergistic polymer yields have been achieved in presence of the additives. The tensile properties of the composite are also reported. (author).

1991-01-01

336

Standardisation of techniques for evaluation of solidified high level waste product: A status report  

Science.gov (United States)

The results of studies on: (1) development of suitable glass compositions for solidification and vitrification of high level radioactive wastes, and (2) the characteristics of these compositions, namely, leaching, mechanical properties, thermal conductivity, viscosity and homogeneity evaluation are reported. Inactive simulated purex waste was used for compositions reported herein. The data generated on leaching and other product characteristics of the selected vitrified waste products was used to evaluate the performance of corresponding experimental units and techniques with respect to their reproducibility and reliability.

1981-01-01

337

Standard samples for X-ray radiometric analysis of substance composition  

International Nuclear Information System (INIS)

Some aspects of metrological provision of X-ray radiometric analyzers for mineral raw composition and gamma-gamma-logging equipment are considered. Standard samples (SS) based on the phenol-formaldehyde resin with the introduced quantities calculated of element compositions in the form of oxides and salts are described. Principles of metrological provision developed are used when carrying out state acceptance tests of X-ray radiometric analyzer RAL-M-102 ''Ehkran'' and gamma-gamma-logging equipmnt RSK-102. Economic benefit from introduction of an SS set is #approx# 60-100 thousand roubles per year.

338

Resistance of radiation-induced tropical wood-polymer composites to fungal degradation  

Energy Technology Data Exchange (ETDEWEB)

The resistance of six tropical hardwoods to fungal degradation by two wild-type strains of Phanerochaete chrysosporium Burdsall was investigated using vermiculite burial and wood-block weight loss techniques. Radiation-induced wood-polymer composites (WPC), based on two hardwoods Ramin and Rubberwood with methyl methacrylate, were prepared, and samples were also exposed to the wood-rotting fungus. A significant improvement in resistance to fungal decay was observed in the WPC. Scanning-electron micrographs of the two woods and their composites after fungal degradation are presented and discussed.

1987-01-01

339

Radio-frequency and microwave load comprising a carbon-bonded carbon fiber composite  

Energy Technology Data Exchange (ETDEWEB)

A billet of low-density carbon-bonded carbon fiber (CBCF) composite is machined into a desired attenuator or load element shape (usually tapering). The CBCF composite is used as a free-standing load element or, preferably, brazed to the copper, brass or aluminum components of coaxial transmission lines or microwave waveguides. A novel braze method was developed for the brazing step. The resulting attenuator and/or load devices are robust, relatively inexpensive, more easily fabricated, and have improved performance over conventional graded-coating loads.

1998-01-01

340

Phenomenological modeling of the stress-strain behaivor of ceramic matrix composites with application to stress analysis  

Energy Technology Data Exchange (ETDEWEB)

A plane stress constitutive relation is developed for laminate composites undergoing matrix cracking and therefore displaying significant nonlinear stress-strain behavior. The constitutive relation is similar in some respects to a phenomenological theory of plasticity in that it is fit to data from uniaxial tests. The constitutive equations are specialized to brittle matrix composites (especially CMCs) in the form of cross-piles and quasi-isotropic laminates. Several problems involving stress redistribution at holes and notches due to nonlinear stress-strain behavior are investigated with the aid of the constitutive law.

1995-12-31

341

Peculiarities of crack propagation in laminated composite materials and their influence on resilience absorbed energy  

International Nuclear Information System (INIS)

Presented are the results of the investigation of the kinetics and micromechanism of the failure in impact bending of oriented-crystallized specimens having the eutectic composition Ni_3Al-Ni_3Nb and of the bimetal composed of 45 steel + M3 copper. The failure kinetics was studied by high-speed filming, whereas the fractures were studied by electron fractography. The particularities of the failure of the laminar-type composite materials were found. Analyzed was the effect of the kinetic factors and the mechanism of failure upon its energy consumption.

342

Nondestructive Technique Survey for Assessing Integrity of Composite Firing Vessel  

Energy Technology Data Exchange (ETDEWEB)

The repeated use and limited lifetime of a composite tiring vessel compel a need to survey techniques for monitoring the structural integrity of the vessel in order to determine when it should be retired. Various nondestructive techniques were researched and evaluated based on their applicability to the vessel. The methods were visual inspection, liquid penetrant testing, magnetic particle testing, surface mounted strain gauges, thermal inspection, acoustic emission, ultrasonic testing, radiography, eddy current testing, and embedded fiber optic sensors. It was determined that embedded fiber optic sensor is the most promising technique due to their ability to be embedded within layers of composites and their immunity to electromagnetic interference.

2000-08-01

343

Microbuckling compression failure of a radiation-induced wood/polymer composite  

Energy Technology Data Exchange (ETDEWEB)

A wood/polymer composite was produced by impregnating Ramin wood with methyl methacrylate monomer and subsequently polymerizing it by gamma irradiation. To assess the improvement in compression strength of the wood caused by the polymer impregnation, a microbuckling compression failure mechanism was used to model the compression failure of the composite. Such a mechanism was found to predict a linear relationship between the compression strength and the percentage polymer impregnation (by weight). Uniaxial compression test results at 45({plus minus}5)% and 90({plus minus}5)% relative humidity levels, after being statistically analysed, showed that such a linear relationship was valid for up to 100% polymer impregnation. (author).

1990-01-01

344

Microbuckling compression failure of a radiation-induced wood/polymer composite  

International Nuclear Information System (INIS)

A wood/polymer composite was produced by impregnating Ramin wood with methyl methacrylate monomer and subsequently polymerizing it by gamma irradiation. To assess the improvement in compression strength of the wood caused by the polymer impregnation, a microbuckling compression failure mechanism was used to model the compression failure of the composite. Such a mechanism was found to predict a linear relationship between the compression strength and the percentage polymer impregnation (by weight). Uniaxial compression test results at 45(#+-#5)% and 90(#+-#5)% relative humidity levels, after being statistically analysed, showed that such a linear relationship was valid for up to 100% polymer impregnation. (author).

1990-01-01

345

Mechanical Properties of Carbon Nanotubes / Hydroxyapatite Composites Prepared by Spark Plasma Sintering  

International Nuclear Information System (INIS)

In this study, Multi-Walled Carbon Nanotubes (MWCNTs) / Hydroxylapatite (HAp) composites were made to improve mechanical properties by using Spark Plasma Sintering (SPS) method. Slurry 6 mol of CaHPO4#centre dot#2H2O (DCPD), 4 mol calcium hydroxide and MWCNTs were mixed and sintered by using SPS at 5-120 MPa pressure, 1200-1250 deg. C and in vacuum or N2 atmosphere. The fracture toughness of sintered MWCNTs/HAp composites was increased.

2006-05-05

346

Gelcasting compositions having improved drying characteristics and machinability  

Energy Technology Data Exchange (ETDEWEB)

A gelcasting composition has improved drying behavior, machinability and shelf life in the dried and unfired state. The composition includes an inorganic powder, solvent, monomer system soluble in the solvent, an initiator system for polymerizing the monomer system, and a plasticizer soluble in the solvent. Dispersants and other processing aides to control slurry properties can be added. The plasticizer imparts an ability to dry thick section parts, to store samples in the dried state without cracking under conditions of varying relative humidity, and to machine dry gelcast parts without cracking or chipping. A method of making gelcast parts is also disclosed.

2001-01-01

347

Fabrication of beta-sialon having high hardness  

International Nuclear Information System (INIS)

Hardness of beta-sialon with four different composition index values of 0.25, 0.50, 0.75 and 1.0 in the system Ni/sub 3/N/sub 4/-AlN-Al/sub 2/O/sub 3/ with the addition of 6% Y/sub 2/O/sub 3/ as sintering aid has been reported. These composition were pressureless sintered for 90, 180 and 270 min in nitrogen atmospheres at temperatures ranging from 1650 to 1800 deg. C. Highest hardness was achieved when the composition index was 0.25 was sintered for 270 minutes at 1750 deg. C. (author).

348

Engineering electromagnetic response of composite terahertz metamaterial with broken symmetry  

Science.gov (United States)

We proposed and numerically investigated the influence of spatial symmetry on the terahertz frequency region response of composite planar metamaterials based on deformed split ring resonators. Compared with the original simple structures, the composite metamaterials with different spatial symmetries exhibited exotic electromagnetic properties. The electromagnetic response of a specific configuration with C4 symmetry was identical to the structure with simple lattice. Especially, for configurations with broken symmetry, very sharp Drude-like resonances with high quality factor were observed. The electric field and current distribution associated the resonances were analyzed for deep understanding of the underlying physical properties.

2011-09-01

349

Electron microscopy analysis of grain boundary structure and composition in superplastically deformed Al-Mg alloys  

Energy Technology Data Exchange (ETDEWEB)

Evaluation of grain boundary composition and structure in superplastically deformed AA5083-based alloys (Al-4.5Mg-1.6Mn-0.2Zr) was carried out in a field-emission gun transmission electron microscope (FEG-TEM). During superplastic deformation at high homologous temperatures materials undergo extensive grain boundary sliding (GBS) which creates a flow of defects in the near-boundary region. Recent literature has shown that the grain-boundary composition in Al-Mg alloys is not necessarily the same as the matrix, and that these differences can have an effect on GBS.

1996-12-31

350

Composition of insoluble kerogen-like organic polymer in the carbonate rocks of Orenburg gas-condensate deposit  

British Library Electronic Table of Contents (United Kingdom)

The concentrates of scattered organic matter???kerogen-like polymer, which is insoluble in acids and organic solvents???were isolated from rock samples taken at different depths from various stratigraphic units at the productive deposits of the Orenburg oil-gas condensate field using chemical methods. The chemical composition of the kerogen-like polymer and the concentrations of trace elements in it were studied. The regularities of evolutionary changes in the composition of the organic matter and the concentrations of trace elements in it in the order of the kerogen-like polymer and the following its consecutive derivatives were established: asphaltenes, ethanol-benzene tars, benzene tars, oils, and paraffins

2011-01-01

351

Change in the chemical composition and surface properties of high-silica zeolites in activating treatments and during a catalytic reaction  

Science.gov (United States)

The surface composition and composition near the surface and properties of high-silica zeolites of the TsVK-1 type were studied by XPES, IRS, and low-temperature adsorption of N/sub 2/. It was found that changing the sequence of operations during preparation of the H form of the zeolites results in a different set of acid centers on their surface, caused by migration of cations into the bulk of the zeolites. Migration of elements is also observed during the catalytic reaction of conversion of ethanol.

1988-08-01

352

Carbon fibers and composites modified by intercalation  

International Nuclear Information System (INIS)

The aim of this paper was to describe ability to intercalation of laboratory prepared carbon composites and their constituents. In work the following materials were tested; pinch-based fibres of P-120 and K-1100 manufacturer's designations, carbon matrix and resulting composites. To prepare a matrix of composites, phenol-formaldehyde resin (Z) and pinch-based precursor (PAK) were used. After initial carbonization, the carbon matrix was heated to 2150 "oC i to improve ability to the future intercalation. Three kinds of composites (P/Z, K/Z and K/PAK), with two directional reinforcement (2D), were prepared. All carbon samples were intercalated with copper chloride(II). To study the structure of all materials, before and after intercalation, X-ray diffraction method was used. It enabled to measure microstructure parameters (L_c and L_a), interplanar distance (d_0_0_2) thickness of an intercalation layer ...

353

BURST STRENGTH AND NON-DESTRUCTIVE EVALUTION OF COMPOSITE PIPES AND PIPE COUPLINGS WITH DEFECTS (TOP 48)  

Environmental Research Database

ObjectivesObjectives Not AvailableDescriptionTo determine the effects of water penetration on the burst strength of filament wound composite pipes which have been damaged by impact and then subjected to long term pressurisation with sea water. ~%~ To monitor and characterise the damage and effects of sea water penetration using ultrasonic NDT. To determine the burst strength of bonded composite pipe joints with and without defects and to see whether the defects can be detected using ultrasonic NDT. [continued...

1996-01-31

354

Application of fracture mechanics to cementitious composites  

Energy Technology Data Exchange (ETDEWEB)

This work contains 27 chapters which cover recent advances in fracture mechanics applied to cement-based composites: concrete, reinforced concrete, and fiber reinforced concrete. The book, based on a NATO Advanced Study Institute, is a comprehensive survey of treating nonlinearity associated with crack growth in brittle materials such as cement composites, rocks and ice. The book is divided into 8 major themes: advances in nonlinear fracture mechanics; fracture processes; numerical modelling of fracture; experimental methods of determining fracture parameters; damage and continuum modelling; strain-rate and dynamic effects of crack propagation; stress-corrosion, time and temperature effects on fracture; and implications for concrete structures.

1985-01-01

355

An evaluation of three methods of bonding resin composite to stainless steel.  

Science.gov (United States)

Three bonding agents were evaluated to determine which were most effective in enhancing the bond of resin composite to stainless steel. A light-activated resin composite was bonded to a total of 60 stainless steel specimens using Panavia, Cover-Up, or Silicoating. Tensile bond strength measurements revealed that all three agents provide a satisfactory means of increasing adherence of the esthetic veneer without decreasing bonding through thermocycling of the specimens. Panavia and Cover-Up were significantly more effective than Silicoating and appear to be easier to use. PMID:8297460

356

#alpha#-Sialon - new opportunities via new microstructure  

International Nuclear Information System (INIS)

Both microstructural graded and homogenous single-phase #alpha#-Sialon is obtained from Si_3N_4 powder for a broad range of compositions of practical interest. Elongated grains of #alpha#-Sialon could be developed in the monophase material by controlled mechanism of nucleation and growth. Tailoring of microstructure was realized through slow transformation reaction from Si_3N_4 to #alpha#-Sialon at lower temperature than sintering temperature when the composition is near the #alpha#-Sialon phase boundary. The mechanical properties are strongly correlated with the microstructure and are enhanced greatly in the optimized Sialon composition. (author)

2001-05-01

357

iMAST Quarterly, Number 1, 1998  

Science.gov (United States)

... Airframe System Technoloqies Laser fabricated flooring Composite sandwich panels for noise control Spray formed HS aluminum alloys Protective ...

2011-05-14

358

X-Ray Fluorescence Analysis of Composite Propellants for ...  

Science.gov (United States)

... The constancy of the X-ray intensity ratio for each element in Table 8 as the X-ray tube settings were changed shows the excellent compensating ...

1977-06-03

359

Variation of surface composition and sintering of binary Pd{sub 7}Ag{sub 3} nanoparticles  

Energy Technology Data Exchange (ETDEWEB)

The variation of surface composition and sintering of the binary Pd{sub 7}Ag{sub 3} nanoparticles prepared by chemical reduction were studied. The composition of the as-prepared Pd{sub 7}Ag{sub 3} nanoparticles across the diameter is inhomogeneous due to different reduction potentials of Pd and Ag. Upon heating, Ag will migrate to the surface because of its lower surface energy. Surface modification results in variation of surface composition during the sintering process. Stearic acid acts as a grain growth inhibitor. The migration of Ag to the surface is suppressed and the sintering is retarded. Modification by polyethylene glycol leads to more migration of Ag atoms from the core to the surface. This makes the nanoparticles easier to sinter.

2006-05-18

360

Variation of surface composition and sintering of binary Pd_7Ag_3 nanoparticles  

International Nuclear Information System (INIS)

The variation of surface composition and sintering of the binary Pd_7Ag_3 nanoparticles prepared by chemical reduction were studied. The composition of the as-prepared Pd_7Ag_3 nanoparticles across the diameter is inhomogeneous due to different reduction potentials of Pd and Ag. Upon heating, Ag will migrate to the surface because of its lower surface energy. Surface modification results in variation of surface composition during the sintering process. Stearic acid acts as a grain growth inhibitor. The migration of Ag to the surface is suppressed and the sintering is retarded. Modification by polyethylene glycol leads to more migration of Ag atoms from the core to the surface. This makes the nanoparticles easier to sinter.

2006-05-18

361

Tris(2,2prime-bipyridyl)ruthenium(II) Electrogenerated Chemiluminescence Sensor Based on Platinized Carbon Nanotube-Zirconia-Nafion Composite Films  

British Library Electronic Table of Contents (United Kingdom)

Mesoporous films of platinized carbon nanotube-zirconia-Nafion composite have been used for the immobilization of tris(2,2prime-bipyridyl)ruthenium (II) (Ru(bpy)32+) on an electrode surface to yield a solid-state electrogenerated chemiluminescence (ECL) sensor. The composite films of Pt-CNT-zirconia-Nafion exhibit much larger pore diameter (3.55 nm) than that of Nafion (2.82 nm) and thus leading to much larger ECL response for tripropylamine (TPA) because of the fast diffusion of the analyte within the films. Due to the conducting and electrocatalytic features of CNTs and Pt nanoparticles, their incorporation into the zirconia-Nafion composite films resulted in the decreased electron transfer resistance within the films. The present ECL sensor based on the Pt-CNT-zirconia-Nafion gave a lin...

2010-01-01

362

Tris(2,2'-bipyridyl)ruthenium(II) electrogenerated chemiluminescence sensor based on carbon nantube dispersed in sol-gel-derived titania-Nafion composite films  

International Nuclear Information System (INIS)

A highly sensitive and stable tris(2,2'-bipyridyl)ruthenium(II) (Ru(bpy)_3 "2"+) electrogenerated chemiluminescence (ECL) sensor was developed based on carbon nanotube (CNT) dispersed in mesoporous composite films of sol-gel titania and perfluorosulfonated ionomer (Nafion). Single-wall (SWCNT) and multi-wall carbon nanotubes (MWCNT) can be easily dispersed in the titania-Nafion composite solution. The hydrophobic CNT in the titania-Nafion composite films coated on a glassy carbon electrode certainly increased the amount of Ru(bpy)_3 "2"+ immobilized in the ECL sensor by adsorption of Ru(bpy)_3 "2"+ onto CNT surface, the electrocatalytic activity towards the oxidation of hydrophobic analytes, and the electronic conductivity of the composite films. Therefore, the present ECL sensor based on the CNT-titania-Nafion showed improved ECL sensitivity for tripropylamine (TPA) compared to the ECL sensors based on ...

2006-04-13

363

Tris(2,2'-bipyridyl)ruthenium(II) electrogenerated chemiluminescence sensor based on carbon nantube dispersed in sol-gel-derived titania-Nafion composite films  

Energy Technology Data Exchange (ETDEWEB)

A highly sensitive and stable tris(2,2'-bipyridyl)ruthenium(II) (Ru(bpy){sub 3} {sup 2+}) electrogenerated chemiluminescence (ECL) sensor was developed based on carbon nanotube (CNT) dispersed in mesoporous composite films of sol-gel titania and perfluorosulfonated ionomer (Nafion). Single-wall (SWCNT) and multi-wall carbon nanotubes (MWCNT) can be easily dispersed in the titania-Nafion composite solution. The hydrophobic CNT in the titania-Nafion composite films coated on a glassy carbon electrode certainly increased the amount of Ru(bpy){sub 3} {sup 2+} immobilized in the ECL sensor by adsorption of Ru(bpy){sub 3} {sup 2+} onto CNT surface, the electrocatalytic activity towards the oxidation of hydrophobic analytes, and the electronic conductivity of the composite films. Therefore, the present ECL sensor based on the CNT-titania-Nafion showed improved ECL sensitivity for tripropylamine (TPA) ...

2006-04-13

364

Transcriptional Regulation of Membrane Lipid Homeostasis in Escherichia coli*  

UK PubMed Central (United Kingdom)

The biophysical properties of membrane phospholipids are controlled by the composition of their constituent fatty acids and are tightly regulated in Escherichia...Full Text Available

2009-12-11

365

Theoretical Basis of Protocols for Seed Storage  

UK PubMed Central (United Kingdom)

The protocols presently established for optimum seed storage do not account for the chemical composition of different seed species, the physiological status of the seed, and the physical status of water...Full Text Available

1990-11-01

366

The role of fatty acid desaturases in epidermal metabolism  

UK PubMed Central (United Kingdom)

The lipid composition of skin is important to a variety of functions served by this organ. Therefore, skin expresses multiple enzymes that synthesize and metabolize lipids. An important class of lipid...Full Text Available

2011-04-01

367

The giant linear magnetostriction in elastic ferromagnetic composites within a porous matrix  

Energy Technology Data Exchange (ETDEWEB)

In this article, a method of producing elastic ferromagnetic composite containing particles of chemical pure iron with sizes of 0.10-0.15 mm was described. The particles were dispersed in an elastic matrix of an elastic silicone rubber. The filling factor of composite by ferromagnetic particles and porous factors were changed in the range from 0.15 to 0.45. The samples of the obtained composite were placed in the magnetic field with induction of 0-8 T, produced by the Bitter-type magnet. The longitudinal magnetostriction of samples was measured by using a coaxial capacitor with a movable plate. It was found that the maximal relative elongation of samples was 4.81% and hysteresis of magnetostriction and also remanent magnetostriction amounted to 1.08%. A slow decay of remanent magnetostriction up to 0.14% in 10{sup 5} s was also observed.

2006-06-15

368

The effect of wood extractives on the thermal stability of different wood-LLDPE composites  

Energy Technology Data Exchange (ETDEWEB)

The thermal stability of wood polymer composites made with extractive-free wood from four different wood species was studied. Hot water (HW) extractives, ethanol/cyclohexane (E/C) extractives and both types of extractives were eliminated from A. cyclops, E. grandis, P. radiata and Q. alba. Composites of LLDPE and 10 wt% of wood were prepared, using poly vinyl alcohol-co-ethylene (EVOH) as a compatibilizer. The thermal degradation behavior of the composites was characterized with thermogravimetric analysis (TGA). The obtained results showed that in all cases, the degradation temperatures shifted to higher values after removal of the extractives. The removal of E/C extractives was less effective in its improvement of the thermal stability than the removal of HW extractives. The largest improvement on the thermal stability of WPCs was achieved when both types of extractives (E/C and HW) were removed.

2009-01-05

369

The effect of aqueous composition on diffusion coefficient in bentonite  

International Nuclear Information System (INIS)

The diffusion coefficients (De) in bentonite were measured to understand and quantify the influence of groundwater chemistry such as ionic strength and to quantify the alteration of smectite mineralogical transformations. (author)

2009-12-01

370

The carbon fiber surface treatment and addition of PA6 on tensile properties of ABS composites  

British Library Electronic Table of Contents (United Kingdom)

In this study acrylonitrile-butadiene-styrene (ABS) terpolymer was reinforced with HNO3-treated short carbon fibers (HCFs). The effects of HCF concentration on the tensile properties of the composites were examined. Increasing the HCF concentration in the ABS matrix from 10 wt% to 30 wt% resulted in improved tensile strength and tensile modulus. To obtain a strong interaction at the interface, polyamide-6 (PA6) at varying concentrations was introduced into the ABS/10 wt% HCF composite. The incorporation and increasing amount of PA6 in the composites increased tensile properties of the ABS/PA6/HCF systems due to the improved adhesion at the interface, which was confirmed by the ratio of tensile strength as an adhesion parameter. These results were also supported by scanning electron microgr...

2011-01-01

371

TOPIC 02 High Speed Travel - NASA's SBIR & STTR Programs  

Science.gov (United States)

Low-cost fabrication of PMC composite sandwich panels, including metallic surface preparations for bonding the PMC to titanium honeycomb. ...

372

T. I --. - NASA Technical Report Server (NTRS)  

Science.gov (United States)

curves are also directly translatable to metal-matrix composites. ..... 4~f4'4 ..... result of learning curve. The most important reduction in cost as a ...

373

Synthesis and characterization of conducting polymer composite (PAn/TiO{sup 2}) for cathode material in rechargeable battery  

Energy Technology Data Exchange (ETDEWEB)

This paper deals with the preparation and characterization of polyaniline/TiO{sub 2} composite by XRD, UV-VIS spectra, TGA/DTA and FTIR. The composite is used as a cathode material for rechargeable battery comprising of zinc container as the anode, cellulose acetate as the separator and polyvinyl sulfate and carboxy methyl cellulose as the solid polymer electrolytes (SPE). By using the PAn/TiO{sub 2} composite as the cathode material, the cylindrical AA type rechargeable battery was fabricated and the following output was observed. The open circuit voltage (OCV) is 1.4 V and current is 250 mA to 1.0 A, 50 recharge cycles, power density is 350 A h/kg and power efficiency is 70%.

2003-02-01

374

Surface oxidation of Co2+ and its dependence on ligand coordination number in silica polyamine composites  

British Library Electronic Table of Contents (United Kingdom)

Coordination of CoCl2 solutions to the silica polyamine composite, WP-1, made with the branched polymer polyethylenimine (PEI) shows irreversible binding resulting from surface oxidation of the Co2+-Co3+. This is not the case for the silica polyamine composite BP-1 made with the linear polymer polyallylamine where reversible binding and no oxidation is observed. These observations suggested that oxidation of the cobalt was related to the greater coordination number available with the branched polyamine relative to the linear polyamine. A study of the kinetics of cobalt binding to WP-1 indicated initial loading of Co2+ at relatively low coordination number followed by desorption of Co2+ leading to oxidation and irreversible binding. Exclusion of oxygen from the composite-cobalt solution mix...

2010-01-01

376

Structural Response of Marine Sandwich Panels to Uniform ...  

Science.gov (United States)

... Composite sandwich panels with fiber reinforced plastic (FRP) faces and low 3 density foam cores are fast becoming the structural material of ...

1990-06-01

377

Stabilization of geothermal residues by encapsulation in portland cement-based composites  

Energy Technology Data Exchange (ETDEWEB)

Presented are the results from a laboratory test program conducted to identify and evaluate materials for converting hazardous geothermal residues to a non-hazardous and potentially usable form. Results indicate that the residues can be effectively incorporated, as a fine aggregate, into portland cement-based composites. Five geothermal residues obtained from sites in the Salton Sea area of California were evaluated. Three of these were classified as hazardous. After mixing with cement, the leach rates were all well below specified levels. Although structural-grade composites were produced, gradual reductions in properties with time up to 1 yr were noted. This indicates ongoing chemical reactions between the cement paste and the constituents of the residues. Further research is necessary before the composites could be considered for use in structural applications. 3 refs., 8 tabs.

1988-05-01

378

Size-controlled Ag nanoparticle modified WO3 composite films for adjustment of electrochromic properties  

British Library Electronic Table of Contents (United Kingdom)

Size-controllable Ag nanoparticle ultrathin films, which were fabricated by vacuum deposition method from high purity Ag wire onto cleaned indium tin oxide conducting glass, have different color fabricated by variation of preparation conditions. The UV/Vis spectra showed that optical absorption peak of these Ag nanoparticle films can be tuned in a range from 457nm to >650nm. Scanning electron microscopy images showed that with increasing film thickness Ag particle size was larger. Ag/WO3 composite films were prepared by cathodic electrodeposition of WO3 onto the surface of Ag nanoparticle films. Spectroelectrochemistry and electrochromic properties of the resulting composite films were characterized. It was found that the electrochemical and electrochromatic properties of the composite fil...

2010-01-01

379

Size Effects in Impact Damage of Composite Sandwich Panels Alan ...  

Science.gov (United States)

Wade. Jackson. - Army. VTD at NASA. Langley. ABSTRACT. Panel size has a large effect on the impact response and resultant damage level of honeycomb sandwich ...

381

Radiation processing of fibre-reinforced composites  

International Nuclear Information System (INIS)

Electron beam (EB) processing involves using electrons to initiate polymerization or cross-linking reactions in suitable substrates, thereby enhancing specific physical and chemical properties. A relatively new use of EB processing is now emerging: the production of fibre-reinforced composites. EB curing at ambient temperature has the potential to reduce the residual stresses in an advanced composite, a result of expansion during thermal curing, and to significantly increase the overall cure speed and process throughput. Wood fibres are used as a filler material for various thermoplastics such as polypropylene. EB treatment, combined with selected EB-curable coupling agents, significantly increases the adhesion between the wood fibres and the thermoplastic polymer, resulting in improved material properties. Work to develop both products and processes for the EB curing of fibre-reinforced composites is currently underway at ...

1991-06-09

382

Radiation processed composite materials of wood and elastic polyester resins  

International Nuclear Information System (INIS)

The radiation polymerization of multifunctional unsaturated polyester-monomer mixtures in wood forms interpenetrating network system. The mechanical resistance (compression, abrasion, hardness, etc.) of these composite materials are generally well over the original wood, however the impact strength is almost the same or even reduced, in comparison to the wood itself. An attempt is made using elastic polyester resins to produced wood-polyester composite materials with improved modulus of elasticity and impact properties. For the impregnation of European beech wood two types of elastic unsaturated polyester resins were used. The exothermic effect of radiation copolymerization of these resins in wood has been measured and the dose rate effects as well as hardening dose was determined. Felxural strength and impact properties were examined. Elastic unsaturated polyester resins improved the impact strength of wood composite ...

1982-09-19

383

Pulsed Plasma Preparation for LWIR Materials  

Science.gov (United States)

... at compositions below -AlP 4 the films were still unstable, hydrolysing in room air, and the long term stability of higher aluminium phosphides is in ...

1990-06-18

384

Production of Amylase in Liquid Culture by a Strain of Aspergillus oryzae  

UK PubMed Central (United Kingdom)

The effect of different media and pH on the formation of amylase by Aspergillus oryzae EI 212 is described. Depending upon the composition of the medium and growth...Full Text Available

1970-04-01

386

Preparation and properties of environmental friendly nonhalogen flame retardant melamine cyanurate/nylon 66 composites  

British Library Electronic Table of Contents (United Kingdom)

Abstract Melamine cyanurate (MCA) was utilized as an environmental friendly additive to prepare the nonhalogen flame retardant MCA/Nylon 66 composites by melt blending technique. Because of the strong hydrogen bond interactions and fine interfacial compatibility between MCA and Nylon 66, the resultant even dispersion of MCA filler in polymer matrix leads to the better toughness and strength of MCA/Nylon 66 composites than those of neat Nylon 66. Both Nylon 66 and MCA/Nylon 66 composites exhibit similar -crystalline structure, but the presence of MCA influences the distribution of 1 and 2 crystalline phases in Nylon 66 by inducing its hydrogen-bonded sheet separation. Moreover, the blending of MCA and Nylon 66 increases the crystallization temperature and exothermicity but decreases the the...

2011-01-01

387

Preparation and characterization of nano hydroxyapatite/polymeric composites materials. Part I  

British Library Electronic Table of Contents (United Kingdom)

The present study is focused on preparation of nano composite materials and the effect of citric acid on their different properties. The formation of nano HA and its interaction with chitosan (C), gelatin (G) polymers and citric acid (CA) materials were studied. The Fourier Transformed Infrared Spectroscopy (FT-IR), X-ray diffraction (XRD), thermo-gravimetric analysis (TGA), transmission electron microscope (TEM), and scanning electron microscope (SEM) were used to characterize these composite materials. The compressive strength (CS) was also measured to know the reinforcement of the prepared composites. The results show that carboxylic and amino groups play crucial role for HA formation on chitosan-gelatin polymeric matrix in the presence of citric acid (CA). The formation of nano HA part...

2011-01-01

388

Preparation and applications of wood-polyester composites  

International Nuclear Information System (INIS)

Optimum processing parameters were searched for the pilot-scale production of wood-polyester composites by irradiation of resin-impregnated wood material. The radiation initiation of the following systems were examined in wood and without wood matrix: methyl methacrylate, mixture of styrene and acrylonitryle, and their combination with unsaturated polyester. In the most cases the over-all rate of the complete polymerization process in wood matrix is proportional to the square root of the initiation rate. The parameters of the radiation technology of wood-polyester composites have been determined, using 260 TBq (7 kCi) "6"0Co radiation source. A pilot plant has been constructed using an underwater irradiation system of 1.85 PBq (50 kCi) "6"0Co. The successful production rate of 200 kg wood-polyester composite per day, as well as the application tests have demonstrated the technical feasibility of this new structural ...

1982-01-01

389

Plasticity in patterns of histone modifications and chromosomal proteins in Drosophila heterochromatin  

UK PubMed Central (United Kingdom)

Eukaryotic genomes are packaged in two basic forms, euchromatin and heterochromatin. We have examined the composition and organization of Drosophila melanogaster heterochromatin in...Full Text Available

2011-02-01

390

Photodegradation and photostabilization of weathered wood flour filled polyethylene composites  

Science.gov (United States)

Wood plastic composites (WPCs) have gained popularity as building materials because of their usefulness in replacing solid wood in a variety of applications. These composites are promoted as being low-maintenance, high-durability products. However, it has been shown that WPCs exposed to weathering may experience a color change and/or loss in mechanical properties. An important requirement for building materials used in outdoor applications is the retention of their aesthetic qualities and mechanical properties during service life. Therefore, it is critical to understand the photodegradation mechanisms of WPCs exposed to UV radiation and to develop approaches to stabilize these composites against ultraviolet light. In this dissertation, the surface chemistries of weathered composites (both unstabilized and stabilized) as well as the effect of weathering on the color fade and the retention of mechanical ...

2003-01-01

391

Osseointegration of zirconia implants compared with titanium: an in vivo study  

UK PubMed Central (United Kingdom)

BackgroundTitanium and titanium alloys are widely used for fabrication of dental implants. Since the material composition and the surface topography of a biomaterial play a fundamental...Full Text Available

392

NASA SBIR 98-1 Award by Firm - NASA's SBIR & STTR Programs  

Science.gov (United States)

Design of Damage-Tolerant Composite Sandwich Panels with Tear Straps. Sukra Helitek Inc. 3146 Greenwood Road. Ames, IA 50014-4504 ...

393

Multifunctional aerogel thermal protection systems for hypersonic ...  

Science.gov (United States)

Sep 18, 2007 ... Lightweight structural aerogels would find applications as a component of composite sandwich panels that are both lightweight and insulating ...

394

Molecular dynamics study of TiO2/poly(acrylic acid-co-methyl methacrylate) and Fe3O4/polystyrene composite latex particles prepared by heterocoagulation  

British Library Electronic Table of Contents (United Kingdom)

All-atom molecular dynamics simulations were used to study the morphology of polymer/inorganic composite particles prepared by heterocoagulation. The results were also compared to those of our previous study of the preparation of TiO2/poly(acrylic acid-co-methyl methacrylate) and Fe3O4/polystyrene composite particles. In the simulation system, polymer or inorganic particles were simulated by surface-charge-modified C60 or Na atoms. Through a combination of analysis of the radial distribution functions of charged atoms and snapshots of the equilibrated structure, three kinds of particle distributions were observed under different conditions. When the polymer and inorganic particles had opposite surface charges and their sizes were very different, the composite morphology showed a core-shell...

2010-01-01

395

Metal-Matrix Composite Processing Technologies for Aircraft ...  

Science.gov (United States)

... ge aircraft engines (geae) has taken to development an induction plasma deposition (ipd) processing method for the fabrication of ti6242/sic mmc ...

396

Mesoporous Silicon-Based Anodes for High Capacity, High - NASA  

Science.gov (United States)

Aug 6, 2010 ... A new high capacity anode composite based on mesoporous silicon is proposed. By virtue of a structure that resembles a pseudo ...

397

Lowering the activation temperature of TiZrV non-evaporable getter films [for LHC  

CERN Document Server

In order to reduce the activation temperature of the TiZrV alloy, thin films of various compositions were produced by three-cathode magnetron sputtering on stainless-steel substrates. For the characterisation of the activation behaviour the surface chemical composition has been monitored by Auger electron spectroscopy during specific in situ thermal cycles. The volume elemental composition of the film has been measured by energy dispersive X-ray spectroscopy and the morphology (crystal structure and size of the crystallites) has been investigated by X-ray diffraction. The criteria indicating the sample quality and its dependence on film structure and chemical composition are presented and discussed. (13 refs).

2001-01-01

398

Ion processing element with composite media  

Energy Technology Data Exchange (ETDEWEB)

An ion processing element employing composite media disposed in a porous substrate, for facilitating removal of selected chemical species from a fluid stream. The ion processing element includes a porous fibrous glass substrate impregnated by composite media having one or more active components supported by a matrix material of polyacrylonitrile. The active components are effective in removing, by various mechanisms, one or more constituents from a fluid stream passing through the ion processing element. Due to the porosity and large surface area of both the composite medium and the substrate in which it is disposed, a high degree of contact is achieved between the active component and the fluid stream being processed. Further, the porosity of the matrix material and the substrate facilitates use of the ion processing element in high volume applications where it is desired to effectively process a high volume flows.

2009-03-24

399

Interfacial characteristics of wood fiber/polystyrene composites  

Energy Technology Data Exchange (ETDEWEB)

Considerable interest has focused recently on the use of lignocellulosic fibers as a reinforcement for thermoplastic polymers. The combination of these dissimilar materials, however, is characterized by a widespread incompatibility that leads to a weak fiber/polymer interface and poor performance properties for the composite. In an effort to improve compatibility a number of fiber surface modification approaches have been investigated including plasma, ozone, and polymer grafting treatments. Evaluation of adhesion improvements has been complicated by processing variables that are difficult to control. This paper will discuss the use of the-micro-debond test in quantifying the interfacial shear strength (ISS) in wood fiber/polystyrene composites. Wood fibers were modified to different degrees with styrene-maleic anhydride copolymers that varied in their composition. The effect of fiber modification on surface energetics was ...

1995-12-01

400

Influence of short carbon fiber content on mechanical and dielectric properties of Cfiber/Si3N4 composites  

British Library Electronic Table of Contents (United Kingdom)

Cfiber/Si3N4 composites were prepared by hot-pressed sintering using a-Si3N4 powders, short carbon fibers and sintering additives as starting materials. The mechanical and dielectric properties of these composites were studied. When the short carbon fiber content of the composites increases from 0 to 1wt.%, the fracture toughness increases from 3.456 to 4.203MPam1/2, and both the real and imaginary part of permittivity increase greatly over the frequency range 8.2-12.4GHz. These effects were due to the anisotropy of short carbon fibers.

2007-01-01

401

Hydriding properties of a mechanically milled Mg-50 wt.% ZrFe{sub 1.4}Cr{sub 0.6} composite  

Energy Technology Data Exchange (ETDEWEB)

The ball-milling method was used to produce Mg-50 wt.% ZrFe{sub 1.4}Cr{sub 0.6} composite. The thermodynamic, kinetic, and cycling properties, as well as the resistance to oxidation were examined. This composite possesses excellent kinetic properties, even at moderate temperature. Scanning electron microscopy, energy-dispersive spectrum, transmission electron microscopy and X-ray diffraction were used to characterize the composite before and after hydriding. The fine ZrFe{sub 1.4}Cr{sub 0.6} particles covering Mg particles acting as a ''catalytic film'', a significant amount of imperfections and some alloy powder in the Mg matrix introduced by ball milling all contributed to the enhanced absorption/desorption rate. (orig.)

2000-02-02

402

HDL in humans with cardiovascular disease exhibits a proteomic signature  

UK PubMed Central (United Kingdom)

BackgroundAlterations in protein composition and oxidative damage of high-density lipoprotein (HDL) have been proposed to impair the cardioprotective properties of...Full Text Available

2010-07-04

403

Experimental Investigation into the Fatigue Life of Hybrid ...  

Science.gov (United States)

... asymmetric versions of two different methods of joining GRP composite sandwich panels 3with steel were obtained (see Figure 1.7), the idea being ...

2008-06-01

404

Evaluation of adhesive bonded sandwich panels for ...  

Science.gov (United States)

... content of the environment) are significant factors affecting the useful service life of adhesive bonded plastic composite sandwich panels at 650 F ...

1970-10-01

406

Effect of hydroxyapatite content on the microstructure, thermal and mechanical properties of Ti-based glassy alloy/hydroxyapatite composite prepared by spark plasma sintering  

British Library Electronic Table of Contents (United Kingdom)

In the present paper, the effects of hydroxyapatite (HA) content on the microstructure, thermal and mechanical properties of Ti-based glassy alloy/HA composite prepared by spark plasma sintering (SPS) are investigated. The microstructure of the composites is homogeneous when the HA is lower than 2 wt%. When the HA content is higher than 3 wt%, the crystalline precipitates with size of less than 5 nm are distributed in the glassy matrix. HA decomposes during sintering procedure for the composite with high HA content. With increasing HA addition, compressive strength decreases. Especially for the HA content is over 2 wt%, the strength decreases sharply because of partial crystallization of glassy alloy matrix.

2011-01-01

407

Effect of carbon fiber surface treatments on the flexural strength and tribological properties of short carbon fiber/polyimide composites  

British Library Electronic Table of Contents (United Kingdom)

Pitch-based short carbon fibers (CFs) were treated by air oxidation and cryogenic nitrogen, respectively. Thereafter the treated and untreated CFs were incorporated into polyimide (PI) matrix to form composites. The CFs before and after treatment were examined by XPS and SEM.The flexural strength of the specimen was determined in a three-point test machine and the tribological properties of PI composites sliding against GCr15 steel rings were evaluated on an M-2000 model ring-on-block test rig. The results show that the surface of the treated CFs became rougher. Lots of active groups formed on the CF surface after air oxidation.The treatment can effectively improve the mechanical and tribological properties in their PI composites due to the enhanced fiber-matrix interfacial bonding. Copyri...

2008-01-01

408

Effect of Si_3N_4 whisker and SiC platelet addition on phase transformation and mechanical properties of the #alpha#/#beta# sialon matrix composites  

International Nuclear Information System (INIS)

#alpha#/#beta# sialon based composites containing silicon nitride whisker and silicon carbide platelet were fabricated by hot pressing. Effect of the reinforcing agents on the #alpha# to #beta# phase transformation of the sialon as well as on the mechanical properties was investigated. Silicon nitride whisker and silicon carbide platelet promoted the phase transformation. TEM/EDS analysis revealed that the grain containing the whisker had 'core-rim' structure; core being high purity Si_3N_4 whisker and rim being #beta#-sialon. Flexural strength of the composite decreased with the reinforcement addition which, on the other hand, improved fracture toughness of it. High temperature strength was measured at 1300 deg C to be about 130 MPa lower than that measured at RT for the whisker reinforced composite. (author).

410

Effect of Alcohol Solvent on Mixing of Fine Ceramic Powders and Some Properties of Ceramic-Based Composites; Seramikkusu fukugokei ni okeru bifunmatsu kongo ni oyobosu arukoru youbai no eikyo to shoketsutai no seishitsu  

Energy Technology Data Exchange (ETDEWEB)

Effect of alcohol solvent in mixing process on process on the microstructure and sintering behavior of ceramic-based composites was inestigated in detail. The mixture of fine ceramic powders was prepared through the conventional ball-milling method with various alcohol media. The particle distributions of fine ceramic powders were strongly dependent on the kind of alcohol employed during ball-milling. Ceramic-based composites were fabricated by hot-pressing the mixture of fine ceramic powders. Their microstructures and some mechanical properties of the ceramic-based composites were evaluated. It was found that the viscosity of alcohol, surface tension and contat angle greatly affect the sinterbility and some of the mechanical properties of ceramic-based somposites. (author)

1999-07-01

411

Dielectric behaviour of emeraldine base polymer?ZnO nanocomposite film in the low to medium frequency  

British Library Electronic Table of Contents (United Kingdom)

Emeraldine base (EB) polymer?ZnO nanoparticles composite films has been synthesized by solution casting technique on ITO-coated glass substrate and characterized by XRD, FTIR and TEM for their structure and morphology. Dielectric behaviour of these composite films has been investigated in the very low frequency region to medium frequency region (1?kHz?1?MHz). The dielectric constant of the composite with 30% nanoparticles is almost one-tenth of the pure EB. The dielectric value becomes constant in the frequency region greater than 400?kHz. The change in dielectric behaviour of the composite is explained on the basis of multilayered interface formed between the ZnO nanoparticles and emeraldine chains. Nanoparticles have high energy surface which is responsible for the decrease of free volum...

2011-01-01

412

Development Of Very-High-Strength and High-Performance ...  

Science.gov (United States)

... High performance concrete doesn't always refer to enhanced strength, as in the case of VHSC. ... Composite Materials VHSC Concrete ...

2004-12-01

413

DIVISION OF - NASA Technical Reports Server  

Science.gov (United States)

(Lactuca scariole),morning glory (Ipomea sp.), broomsedge (Andropogon virginicus ) and numerous composites. Because this area is leveed -and managed it ...

414

DARPA - Advanced Composite Materials Annual Presentation ...  

Science.gov (United States)

... 66. BV Sankar and MA Pinheiro, "An Offset Beam Finite Element for Fracture Analysis of Delaminations," AIAA Paper Number 90-1024-CP, 31st ...

1992-11-20

415

Coupling of magnetostriction and electrostriction in the porous rheological composite  

Energy Technology Data Exchange (ETDEWEB)

The production method of the elastic composite containing ferrous particles and titanium barium particles dispersed in the porous silicone matrix is described in this article. Since it contains ferrous and titanium barium particles, this composite shows magnetorheological and also electrorheological properties. The electrostriction of composite samples in the electric field with maximal intensity 1.5x10{sup 6} V/m was investigated. The magnetostriction in the magnetic field with maximal induction 1 T was also investigated. It was found that samples elongate with increased electric field intensity, and the magnetic field induction was detected. By increasing the samples' elongation with increase of ferrous particles, titanium barium particles and pores number were also detected. In the investigated division of the electric and magnetic field the elongation changed in a linear way. The maximal elongation achieved was ...

2008-08-15

416

Content of hydrogen, helium, and heavy elements in Procyon  

Energy Technology Data Exchange (ETDEWEB)

The values of X = 0.77, Z = 0.035, and Y = 0.195 and the stage of evolution of Procyon are determined from the evolutionary tracks and the results of an analysis of the chemical composition of the atmosphere.

1985-05-01

417

Compression Behavior of Fluted ... - NASA Technical Reports Server  

Science.gov (United States)

Traditional composite sandwich panels are composed of inner and outer facesheets separated by a core material such as balsa wood, polymeric foam, ...

418

Composition and method for encapsulating photovoltaic devices  

Energy Technology Data Exchange (ETDEWEB)

A composition and method for encapsulating a photovoltaic device which minimizes discoloration of the encapsulant. The composition includes an ethylene-vinyl acetate encapsulant, a curing agent, an optional ultraviolet light stabilizer, and/or an optional antioxidant. The curing agent is preferably 1,1-di-(t-butylperoxy)-3,3,5-trimethylcyclohexane; the ultraviolet light stabilizer is bis-(N-octyloxy-tetramethyl) piperidinyl sebacate and the antioxidant is selected from the group consisting of tris (2,4-di-tert-butylphenyl) phosphite, tetrakis methylene (3,5-di-tert-butyl-4-hydroxyhydrocinnamate) methane, octadecyl 3,5-di-tert-butyl-4-hydroxyhydrocinnamate, and 2,2'-ethylidene bis(4,6-di-t-butylphenyl) fluorophosponite. The composition is applied to a solar cell then cured. The cured product contains a minimal concentration of curing-generated chromophores and resists UV-induced degradation.

2000-01-01

419

Composability, Provability, Reusability (CPR) for Survivability.  

Science.gov (United States)

The goal of this effort Composability, Provability, Reusability (CPR) for Survivability is to address the problem of composition of survivable systems. The particular objective of this project is to construct a formal specification of the Java Virtual Mac...

2002-01-01

420

Comparative study of maleated polypropylene as a coupling agent for recycled low-density polyethylene/wood flour composites  

British Library Electronic Table of Contents (United Kingdom)

Abstract The effects of the type of coupling agent and virgin polypropylene (PP) content on the mechanical properties and water absorption behavior of recycled low-density polyethylene/wood flour (WF) composites were investigated. The fractured surfaces of these recycled wood/plastic composites (rWPCs) were examined to gain insight into the distribution and dispersion of WF within the polymer matrix. The results indicate that the use of 100% recycled polymer led to inferior mechanical properties and to a greater degree of moisture absorption and swelling when compared to recycled polymer-virgin PP wood/plastic composites. This could have been related to the poor melt strength and inferior processability of the recycled polymer. The extent of improvement of the mechanical properties depende...

2011-01-01

421

Cold-atmospheric pressure plasma polymerization of acetylene on wood flour for improved wood plastics composites  

Science.gov (United States)

Plastic composites have become a large class of construction material for exterior applications. One of the main disadvantages of wood plastic composites resides in the weak adhesion between the polar and hydrophilic surface of wood and the non-polar and hydrophobic polyolefin matrix, hindering the dispersion of the flour in the polymer matrix. To improve interfacial compatibility wood flour can be pretreated with environmentally friendly methods such as cold-atmospheric pressure plasma. The objective of this work is therefore to evaluate the potential of plasma polymerization of acetylene on wood flour to improve the compatibility with polyolefins. This presentation will describe the reactor design used to modify wood flour using acetylene plasma polymerization. The optimum conditions for plasma polymerization on wood particles will also be presented. Finally preliminary results on the wood flour surface properties and use in wood plastic ...

2009-10-01

422

Catalyst for the manufacture of acrylonitrile and methacrylonitrile  

Energy Technology Data Exchange (ETDEWEB)

This patent describes a catalyst composition. It consists of the catalytic oxides of iron, bismuth, molybdenum and magnesium as essential components and optionally the oxides of cobalt, nickel, phosphorus and arsenic.

1989-09-05

423

Behavior of particle-filled polymer composite under static and dynamic loading  

British Library Electronic Table of Contents (United Kingdom)

Experimental results of quasi-static and dynamic fracture of particle-filled polymer composite (PFPCM) "ALTUGLAS EI CH25" with a matrix of polymethylmethacrylate (PMMA) are reported in this paper. PMMA matrix is filled with rubber particles, as result a shock-resistant transparent composite is produced. The main task was to investigate experimentally and theoretically the fracture toughness of this composite under static and dynamic loading. A high-rate loading has been created by impulse magnetic field. Analysis of fracture process and its relation with the load parameters and material microstructure have been established. Application of the original testing method enabled determination of fracture toughness at very short loading times and comparison of the results with material dynamic p...

2008-01-01

424

Assessment of the Run to Detonation in Composition B from ...  

Science.gov (United States)

... Thus initiation will be from the shock generated from the front surface of the pellet after traversing the inert packing. Exploding bridgewire detonator ...

1991-02-01

425

Analysis of codon usage and nucleotide composition bias in polioviruses  

UK PubMed Central (United Kingdom)

BackgroundPoliovirus, the causative agent of poliomyelitis, is a human enterovirus and a member of the family of Picornaviridae and among the most rapidly evolving viruses known....Full Text Available

426

An experimental method for measurement of strain distribution between wood the flour particles and polymer matrix on micro-mechanical level  

British Library Electronic Table of Contents (United Kingdom)

Wood plastic composites (WPCs) are comprised of wood flour and thermoplastic polymer. The matrix is typically high-density polyethylene, poly (vinyl chloride), or polypropylene. The effect of morphology and micromechanics of wood flour particles on the mechanical performance of the bulk composite is a relatively unexplored area. The knowledge about the in situ properties of wood particles and the interfacial properties between the wood particles and the polymer matrix in the bio-composites is very limited. The objective of this work is to characterize the full-field deformation and strain distribution in and around wood particles embedded in polymer matrix. The mechanical tests are performed in small-scale tensile loading stage on thin composite samples containing 1-3 wood particles orient...

2011-01-01

427

An Experimental Investigation of Sandwich Flat Panels Under ...  

Science.gov (United States)

... Figure 1.4. Low Velocity Impact 1-4 Page 25. Damage of composite sandwich panels caused by low velocity impact has been ...

1994-12-01

428

Ageing of fibre reinforced polymer composite selected as a bearing material for Rams of 540 MWe fuelling machine  

International Nuclear Information System (INIS)

Fibre-reinforced-polymer-composite material has been suggested as a bearing material to overcome tribological problems witnessed during the testing of Ram assembly of the 540 MWe fuelling machine at RTD. After successful trials at B-Ram the composite material has been adapted for B-RAM, C-Ram and RDB head at fuelling machines being tested at RTD, Hall 7 and at Tarapur. Laboratory evaluations were also carried out at Tribology Lab RTD to study effect of radiation on the composite. Paper deals with the various aspects of life prediction of this material in term of wear and radiation damage. (author)

2006-11-01

429

AeroSpace Information for a Changing World - NASA Technical ...  

Science.gov (United States)

Mar 1, 2011 ... thermal behavior and structural changes of composite sandwich panels with a honeycomb core subjected to a variety of environmental effects. ...

430

AMPA-receptor trafficking and injury-induced cell death  

UK PubMed Central (United Kingdom)

AMPA receptors (AMPARs) are critical for synaptic plasticity, and are subject to alterations based on subunit composition and receptor trafficking to and from the plasma membrane. One of the...Full Text Available

2010-07-01

431

A Finite Element Analysis for ... - NASA Technical Reports Server  

Science.gov (United States)

Composite Sandwich Panels," Proceedings of the American Helicopter Society 60th Annual. Forum, Baltimore, MD, June 7-10, 2004. [7]. Soutis, C., and Fleck, ...

432

:z:..... \\ - NASA Technical Report Server (NTRS)  

Science.gov (United States)

A common reinforced liner material is a cloth formed of PTFE fibers and fiber of ... and ablation protection provided. All of these methods of thermal ..... The influence of fiber content on the microstructures of the composites is ...

433

(#alpha#+#beta#) - Sialon ceramic composites  

International Nuclear Information System (INIS)

(#alpha#+#beta#)-SiALON ceramic composites are industrially important materials. Due to their unique chemistry, crystal structure and microstructural features, #alpha#-SiAlON has superior hardness while #beta#-SiALON offers high strength and toughness. The combination of the two phases enables materials engineers to design a ceramic where the physical properties of the composite can be tailored to a particular application. This article presents a general review of the crystal structures, fabrication and properties of the (#alpha#+#beta#)-SiALON composites with special highlights outlining how microstructural tailoring can control the properties of these advanced ceramic alloys. Copyright (1997) Institute of Metals and Materials Australasia Ltd.

434

Zinc tetraaminophthalocyanine-Fe3O4 nanoparticle composite for laccase immobilization  

UK PubMed Central (United Kingdom)

Zinc tetraaminophthalocyanine-Fe3O4 nanoparticle composites were prepared by organic-inorganic complex technology and characterized. It has been proved that the ZnTAPc dispersed...Full Text Available

2007-12-01

435

Wear resistant composite structure of vitreous carbon containing convoluted fibers. Final report  

Energy Technology Data Exchange (ETDEWEB)

Energy Related Inventions Program Number 613 was a two year program to commercialize a unique new wear material, Metal Reinforced Carbon Composite, MRCC. The program was designed to manufacture sample components of MRCC for evaluation by potential users and manufacturers. As a result of the program Burton Technologies Inc. and Rotary Power International are forming a joint company to manufacture, market and license MRCC materials to a wide range of industries.

1996-05-28

436

The stability of synthetic cutting fluids to microbe damage  

Energy Technology Data Exchange (ETDEWEB)

The resistance to microbe damages of aqueous solutions of cutting fluids (SOZh), which contain dual and more complex mixtures of known compounds, is studied. Lauric acid, myristic and tridecanic acid give microbic resistance to the compositions of synthetic cutting fluids. A complexing of the compositions as a rule does not support precisely expressed effects of synergism or antagonism.

1983-01-01

437

Synthetic fuel composition  

Energy Technology Data Exchange (ETDEWEB)

The title composition comprises methanol containing stearic acid, C/sub 6/H/sub 6/, dextrin, phenol, a combustion accelerator (ethylene dichloride, xylene, Al stearate, a compound of acetic acid); a foaming agent; and ether and an antiknocking agent. The respective ignition point and boiling point of example compounds were 15.1-15.6/sup 0/ and 63.8-64.1/sup 0/.

1981-09-17

438

Sulfidation-resistant alloy/cladding for internal components of coal-conversion equipment. Volume 2. Cladding development. Final report  

Energy Technology Data Exchange (ETDEWEB)

An Fe-19Cr-8Al-0.5Hf alloy has been roll bonded to Alloy 800 to form a protective clad material suitable for use in coal conversion atmospheres. The commercial producibility of both the Fe-19Cr-8Al-0.5Hf alloy and the clad composite has been demonstrated. The clad composite has been shown to exhibit resistance to sulfidation in high sulfur, coal gasification atmospheres low Btu for 2000 hrs at 1800/sup 0/F (1255K). The FeCrAlHf alloy must be preoxidized in the absence of sulfur to form fully protective alumina scales on all surfaces. Useful life of the composite at temperatures of 1400 to 2000/sup 0/F (1033 to 1366K) is governed by reactions at the FeCrAlHf clad alloy 800 interface. The rate of interdiffusion decreases with increasing Ni content and a high Ni alloy such as RA333 appears to be a better substrate than Alloy 800 for a FeCrAlHf composite. The mechanical properties of the clad ...

1981-12-01

439

Studying the internal structure of granular magnetic nanocomposites by ferromagnetic resonance  

British Library Electronic Table of Contents (United Kingdom)

A method for estimating the form of magnetic nanoparticles in composite film structures based on the observation of ferromagnetic resonance phenomenon is offered. Within the model of the effective medium, an explanation is given for experimentally observed concentration and temperature dependences of resonant fields for composite nanosystem (Co45Fe45Z10) f +(Al2O3)100?f .

2010-01-01

440

Report of the results of the fiscal 1997 regional consortium R and D project. Regional consortium energy field / R and D mesoscopic organ control heat-resistant / wear-resistant metal group composite materials (first fiscal year); 1997 nendo chiiki consortium kenkyu kaihatsu jigyo. Chiiki consortium energy bun`ya / mesoscopic fukuso soshiki seigyo tainetsu taimamosei kinzokuki fukugo zairyo no kenkyu kaihatsu (daiichi nendo) seika hokokusho  

Energy Technology Data Exchange (ETDEWEB)

Out of the R and D of mesoscopic metal group composite materials, the paper described the fiscal 1997 results. In the in-situ method as a composite material making method, elucidated to some degree were chemical composition of Fe-C-Cr-V-Nb-Mo-W-Ni base multi-dimensional alloys, and wear resistance and oxidation resistance of MC type carbide dispersion multi-phase texture crystallizing as primary crystal and eutectic. In the composite material making with ceramic fiber and alloy by the pressure infiltration method, the paper clarified the texture formation mechanism in solidification/heat treatment by a combination of Al alloys and alumina long fiber, and the relation between fiber configuration and wear resistance. By MA and MG methods as the powder metallurgy composite material making method, a composed body of {alpha}-stainless steel of Fe-12%Cr composition ...

1998-03-01

441

Preparation of pinewood/polymer/composites using gamma irradiation  

Energy Technology Data Exchange (ETDEWEB)

Wood/polymer composites (WPC) have been prepared from pinewood with different compounds using gamma irradiation: butyl acrylate, butyl methacrylate, styrene, acrylamide, acrylonitrile, and unsaturated polyester styrene resin. The polymer loading was determined with respect to the compound concentration and the irradiation dose. The polymer loading increases generally with increase in the monomer or polymer concentration. Tensile and compression strength have been improved in the four cases, but no improvement was observed using unsaturated polyester styrene resin or acrylamide.

2006-09-15

442

Pore size distribution in ZrO_2-Al_2O_3 composite particles prepared from Zr-Al metallo-organic compounds  

International Nuclear Information System (INIS)

Zr-Al metallo-organic compounds were thermally decomposed to prepare ZrO_2-Al_2O_3 composite powders. The specific surface area was dependent on the organofunctional groups of the starting organic compounds. The pore size distribution was dependent on the heating rate when the heating temperature was the same. 4 refs.; 4 figs.

1989-01-01

443

Phonon relaxation and internal friction in heterogeneous systems based on poly(vinyl chloride)  

British Library Electronic Table of Contents (United Kingdom)

Phonon relaxation and internal friction in kaolin-and bentonite-filled PVC composites are studied. By varying the temperature and/or content of the ultrafine mineral filler in the PVC, one can control the contribution from phonon viscosity, damping force, and the effect of viscosity into the energy dissipation of ultrasonic oscillations in the MHz frequency interval. The dynamic character of the measurements makes it possible to differentiate between relaxation phenomena in the composites and to suggest methods for their controlled changes.

2010-01-01

444

Partial discharge in liquid nitrogen  

Science.gov (United States)

Results are presented of experiments on partial discharge in liquid nitrogen, including insulation breakdown characteristics of liquid nitrogen, partial discharge characteristics of composite insulation systems, lifetime of polymer films, impulse breakdown of polymer films in liquid nitrogen, etc. The partial discharge characteristics of liquid nitrogen are examined with increasing liquid-nitrogen pressure. It is concluded that a composite insulation structure of polymer film and liquid nitrogen can be used as effective electrical insulators at cryogenic temperatures.

1976-01-01

445

On the calculation of the electrolyte aqueous solution freezing temperature  

International Nuclear Information System (INIS)

Analytical expression of the dependence of freezing temperature of electrolyte (CdCl_2, CdSO_4, BeSO_4) aqueous solutions on their composition was found. Three different methods were suggested were suggested for calculation of water activity in multicomponent solution. It was established that sublinear extrapolation of freezing temperature of salt aqueous solutions was possible not up to -5 deg C, but up to -15 deg C, independently of their composition. 6 refs.; 2 figs.

446

Method of removing entrained particles from flue gas and composition of matter  

Energy Technology Data Exchange (ETDEWEB)

A composition of matter to treat particles entrained in flue gas, is described comprising: a caustic liquid used to adjust resistivity of the entrained particles; and inert particulate matter supporting the caustic liquid for inhibiting chemical action of the caustic liquid until used to adjust the resistivity of the entrained particles, the inert particulate matter supporting sufficient caustic liquid to adjust the resistivity of the entrained particles.

1988-04-19

447

Mathematic modeling of the coke gas combustion process  

Energy Technology Data Exchange (ETDEWEB)

Analysis of the coke gas combustion porcess is presented. Standard kinetic relationships were utilized. Calculations were performed for coke gas with high and low content of H/sub 2/ and for blasting air 20 and 100/sup 0/C. Temperature relationships, composition of gas combustion products and release of nitrogen oxides were determined. Results are analyzed which will make it possible to control the composition of combustion products.

1983-01-01

448

Laser cutting plastic materials  

Energy Technology Data Exchange (ETDEWEB)

A 1000-watt CO/sub 2/ laser has been demonstrated as a reliable production machine tool for cutting of plastics, high strength reinforced composites, and other nonmetals. More than 40 different plastics have been laser cut, and the results are tabulated. Applications for laser cutting described include fiberglass-reinforced laminates, Kevlar/epoxy composites, fiberglass-reinforced phenolics, nylon/epoxy laminates, ceramics, and disposable tooling made from acrylic.

1980-08-01

449

Fabrication of continuous mesoporous organic-inorganic nanocomposite films for corrosion protection of stainless steel in PEM fuel cells  

International Nuclear Information System (INIS)

Graphical abstract: Ordered mesoporous organic-inorganic composite film has been achieved by sol-gel and spin-coating techniques. We believe that the mesoporous composite films have a potential application as a protect coating of bipolar plate material. Display Omitted Research highlights: ? Ordered mesoporous composite film was deposited on the 304 stainless steel. ? This composite film exhibited excellent protective performance in 0.5 M H_2SO_4. ? The film exhibited a high surface tension with water contact angle close to 90"o. - Abstract: The organic-inorganic composite film was deposited on the 304 stainless steel as bipolar plate material for proton exchange membrane fuel cells by spin-coating method. As shown by XRD, N_2 adsorption-desorption and TEM, the composite films exhibit ordered mesoporous structures. The corrosion tests in 0.5 M H_2SO_4 system ...

2011-04-01

450

Effect of Ba on ferroelectric and piezoelectric properties of the PLZT (1.2/55/45) system  

International Nuclear Information System (INIS)

Ferroelectric Pb_0_._9_8_2_-_zLa_0_._0_1_2#DELTA#_0_._0_0_6Ba_z(Zr_0_._5_5Ti_0_._4_5)O_3 (PLZT; z = 0-6 mol%) ceramic compositions were fabricated by a mixed-oxide method. X-ray diffraction studies of sintered ceramics indicate the coexistence of rhombohedral and tetragonal phases in the 5 mol% Ba-doped PLZT composition. Grain growth is inhibited with increasing Ba concentration in the PLZT system as evidenced by scanning electron micrographs. Dielectric constant and dielectric loss as a function of temperature suggest that #epsilon#_r_t and tan #delta# are increased up to compositions containing 4 and 5 mol% Ba, respectively. The dielectric maximum (#epsilon#_T_c) decreased to 4 mol% Ba and gradually increased to 6 mol% Ba, whereas, with increasing Ba concentration in the PLZT system, the Curie temperature (T_C) decreased from the composition with no Ba to that with 6 mol% Ba. Relaxor behavior as a ...

2006-06-01

451

Determination of the isomeric composition and structure of bicyclo(3. 3. 1)nonadienes by PMR spectroscopy  

Energy Technology Data Exchange (ETDEWEB)

The isomeric composition of bicyclo(3.3.1)nonadienes was investigated by GLC and PMR spectroscopy with silver-lanthanide shift reagents. The absence of stereospecificity in the hydrogenation of 3,7-dimethylenebicyclo(3.3.1)nonane by hydrogen adsorbed on Raney nickel was demonstrated. This is explained by the sequence of the isomerization and then hydrogenation processes.

1986-01-10

452

Design, development and testing of A31M wood composite stall regulated blade for serial production  

Energy Technology Data Exchange (ETDEWEB)

Despite the long track record of the technology, wood composite has rarely been applied to blades of this scale or for tip braked stall-regulated rotors. This paper describes how the design has been taken successfully from the concept to design through structural testing, certification and operational testing of the prototype set. (orig.)

1999-07-01

453

Densification behavior and properties of Y_2O_3-containing #alpha#-SiAlON-based composites  

International Nuclear Information System (INIS)

Different SiAlON composites based on #alpha#'-SiAlON are investigated, with respect to the phase relationships, densification behavior, and mechanical properties. The compositions are located on a phase-diagram line parallel to the Si_3N_4-Y_2O_3#centre dot#9AlN compound in the Si_3N_4-SiO_2-AlN-Al_2O_3-Y_2O_3-YN system. Analysis of the reaction sequences shows that the formation of the composites is associated with the transient appearance of Y_4Al_2O_9 (YAM), yttrium-aluminum-garnet (YAG), melilite, and a nitrogen-rich liquid phase. The small shift of compositions on the Si_3N_4-Y_2O_3#centre dot#9AlN compound phase-diagram line toward the Al_2O_3-rich side offers the advantage of a higher sinterability and the removal of the melilite phase from a wide range of compositions containing #alpha#'-SiAlON and polytypes. The #alpha#'/#beta#'-SiAlON composites show ...

454

DESCARTES' COMPOSITIONAL THEORY OF MENTAL REPRESENTATION  

British Library Electronic Table of Contents (United Kingdom)

Abstract In his, -Descartes' Ontology of Thought-, Alan Nelson presents, on Descartes' behalf, a compositional theory of mental representation according to which the content of any mental representation is either simple or is entirely constituted by a combination of innate simples. Here the simples are our ideas of God, thought, extension, and union. My objection will be that it is simply ludicrous to think that any four simples are adequate to the task of combining to constitute all of human thought, and that the simples God, thought, extension, and union are particularly ill suited to it.

2011-01-01

455

Composite vector leptoquarks in e"+e-, #gamma#e, and #gamma##gamma# colliders  

International Nuclear Information System (INIS)

We study the signals for composite vector leptoquarks in e"+e- colliders (CERN e"+e- collider LEP II, Next Linear Collider, and CERN Linear Collider) through their effects on the production of jet pairs, as well as their single and pair productions. We also analyze their production in #gamma#e and #gamma##gamma# collisions.

456

Chemical and electrochemical dehydriding characteristics of TiV{sub 2.1}Ni{sub 0.3}-Raney Ni composite prepared by ball-milling in the presence of a reducing agent  

Energy Technology Data Exchange (ETDEWEB)

Composite particles represented as TiV{sub 2.1}Ni{sub 0.3}-Raney Ni(R) were prepared by ball-milling a TiV{sub 2.1}Ni{sub 0.3} alloy with Raney Ni in the presence of 0.01 M sodium hypophosphite (NaH{sub 2}PO{sub 2}) aqueous solution as a reducing agent. The composite particles had different morphology from original TiV{sub 2.1}Ni{sub 0.3} alloy particles and TiV{sub 2.1}Ni{sub 0.3}-Raney Ni composite particles prepared by the ball-milling in the absence of the NaH{sub 2}PO{sub 2} aqueous solution. In charge-discharge cycle tests, the TiV{sub 2.1}Ni{sub 0.3}-Raney Ni(R) composite electrode showed the maximum discharge capacity of 620 mAh g{sup -1}, while its cycle durability was similar to the TiV{sub 2.1}Ni{sub 0.3} alloy electrode, which was explained from depth profiles of constituent elements by Auger electron spectroscopy (AES). In thermogravimetry (TG) and differential thermal analysis (DTA), two ...

2004-02-25

457

Chemical and electrochemical dehydriding characteristics of TiV_2_._1Ni_0_._3-Raney Ni composite prepared by ball-milling in the presence of a reducing agent  

International Nuclear Information System (INIS)

Composite particles represented as TiV_2_._1Ni_0_._3-Raney Ni(R) were prepared by ball-milling a TiV_2_._1Ni_0_._3 alloy with Raney Ni in the presence of 0.01 M sodium hypophosphite (NaH_2PO_2) aqueous solution as a reducing agent. The composite particles had different morphology from original TiV_2_._1Ni_0_._3 alloy particles and TiV_2_._1Ni_0_._3-Raney Ni composite particles prepared by the ball-milling in the absence of the NaH_2PO_2 aqueous solution. In charge-discharge cycle tests, the TiV_2_._1Ni_0_._3-Raney Ni(R) composite electrode showed the maximum discharge capacity of 620 mAh g"-"1, while its cycle durability was similar to the TiV_2_._1Ni_0_._3 alloy electrode, which was explained from depth profiles of constituent elements by Auger electron spectroscopy (AES). In thermogravimetry (TG) and differential thermal analysis (DTA), two steps of dehydriding for hydrided TiV_2_._1Ni_0_._3-Raney ...

2004-02-25

458

BBSRC CASE studentship: The impact of nutrition on the gluten composition and processing quality of wheat  

Environmental Research Database

DescriptionThe objective of this project is to relate the processing quality of wheat to the composition of the developing and mature grain using material grown under a range of nutrient regimes including long term organic and fertilised systems from the Rothamsted Broadbalk experiment, variety trials and organically grown wheat. Preliminary studies have indicated substantial differences in the transcriptome profiles of wheat grown with artificial fertiliser and with organic fertiliser on Broadbalk and tru [continued...

2008-01-31

459

Advanced composite materials made by radiation processing  

Energy Technology Data Exchange (ETDEWEB)

An industrial EB processing line is started to produce cement-bound /CB/ chipboard with radiation cured acrylic coating. The basic features of this line are presented here. The main technological parameters of coating such as: effect of oligomer- and monomer reactivity, monomer functionality, dose-rate and inerting atmosphere on the progress of curing have been discussed. The EB processed CB board is an advanced composite material for the modern lightweight architecture.

1988-01-01

460

Vibration characteristics of SMA composite beams with different boundary conditions  

Energy Technology Data Exchange (ETDEWEB)

Recently, the development of shape memory alloy (SMA) actuators, in the forms of wire, thin film and stent have been found increasingly in the fields of materials science and smart structures and engineering. The increase in attraction for using these materials is due to their many unique materials, mechanical, thermal and thermal-mechanical properties, which in turn, evolve their subsequent shape memory, pseudo-elasticity and super-elasticity properties. In this paper, a common type of SMA actuator, Nitinol wires, were embedded into advanced composite structures to modulate the structural dynamic responses, in terms of natural frequency and damping ratio by using its shape memory and pseudo-elastic properties. A simple theoretical model is introduced to estimate the natural frequency of the structures before and after actuating the embedded SMA wires. The damping ratios of different SMA composite beams were measured through experimental ...

2002-12-15

461

Synthesis of nano Sb-encapsulated pyrolytic polyacrylonitrile composite for anode material in lithium secondary batteries  

Energy Technology Data Exchange (ETDEWEB)

A novel process was proposed to synthesize nano Sb-encapsulated pyrolytic polyacrylonitrile composite for anode material in lithium secondary batteries. The preparation started with the dissolution of SbCl{sub 3} and polyacrylonitrile (PAN) in dimethylformamide (DMF) solution, followed by the addition of KBH{sub 4} to reduce Sb{sup 3+} in the solution. The Sb composite was obtained by pyrolysis of the Sb/PAN mixture that precipitated out when the DMF solution was added by plentiful water. The TEM analysis showed that about 100-200 nm Sb particles were embedded by the pyrolyzed PAN, which provided a conductive matrix to relieve the morphological change of Sb during electrochemical cycling. As-prepared composite presented good cycleability for lithium storage. The proposed process paves an effective way to prepare high performance alloy based composite anode materials for high performance lithium-ion ...

2007-03-01

462

Synthesis and electrochemical performance of carbon nanofiber-cobalt oxide composites  

Energy Technology Data Exchange (ETDEWEB)

Carbon nanofiber (CNF) supported cobalt oxide composites as high-capacity anode materials were prepared through a facile, effective method for potential use in rechargeable lithium-ion batteries. The effects of the calcining temperature on the crystallinity, grain size, specific surface area of Co{sub 3}O{sub 4} and phase transformation from Co{sub 3}O{sub 4} to CoO were studied in detail. Both the specific surface area and CNF content in CNF-cobalt oxide composites strongly affect the electrochemical performance of these series composites. The CNF-Co{sub 3}O{sub 4} composite with 24.3% CNF pyrolyzed at 500 deg. C in Ar shows an excellent cycling performance, retaining a specific capacity of 881 mAh g{sup -1} beyond 100 cycles. Homogeneous deposition and distribution of nanosized Co{sub 3}O{sub 4} particles on the surface of CNF can stabilize the electronic and ionic conductivity as well as the ...

2008-10-15

463

Synthesis and electrochemical performance of carbon nanofiber-cobalt oxide composites  

Energy Technology Data Exchange (ETDEWEB)

Carbon nanofiber (CNF) supported cobalt oxide composites as high-capacity anode materials were prepared through a facile, effective method for potential use in rechargeable lithium-ion batteries. The effects of the calcining temperature on the crystallinity, grain size, specific surface area of Co{sub 3}O{sub 4} and phase transformation from Co{sub 3}O{sub 4} to CoO were studied in detail. Both the specific surface area and CNF content in CNF-cobalt oxide composites strongly affect the electrochemical performance of these series composites. The CNF-Co{sub 3}O{sub 4} composite with 24.3% CNF pyrolyzed at 500{sup o}C in Ar shows an excellent cycling performance, retaining a specific capacity of 881 mAh g{sup -1} beyond 100 cycles. Homogeneous deposition and distribution of nanosized Co{sub 3}O{sub 4} particles on the surface of CNF can stabilize the electronic and ionic conductivity as well as the ...

2008-10-15

464

Study on Sm"1"."8Ce"0"."2CuO"4-Ce"0"."9Gd"0"."1O"1"."9"5 composite cathode materials for intermediate temperature solid oxide fuel cell  

British Library Electronic Table of Contents (United Kingdom)

Sm"1"."8Ce"0"."2CuO"4-xCe"0"."9Gd"0"."1O"1"."9"5 (SCC-xCGO, x=0-12vol.%) composite cathodes supported on Ce"0"."9Gd"0"."1O"1"."9"5 (CGO) electrolyte are studied for applications in IT-SOFCs. Results show that Sm"1"."8Ce"0"."2CuO"4 material is chemically compatible with Ce"0"."9Gd"0"."1O"1"."9"5 at 1000^oC. The composite electrode exhibits optimum microstructure and forms good contact with the electrolyte after sintering at 1000^oC for 4h. The polarization resistance (R"p) reduces to the minimum value of 0.17@Wcm^2 at 750^oC in air for SCC-CGO06 composite cathode. The relationship between R"p and oxygen partial pressure indicates that the reaction rate-limiting step is the surface diffusion of the dissociative adsorbed oxygen on the composite cathode.

2011-01-01

465

Solid oxide fuel cells (Part 2)  

Energy Technology Data Exchange (ETDEWEB)

The project has been developing Yttria Stabilized Zirconia (YSZ)-Alumina Composites as an electrolyte of a self-support type planar Solid Oxide Fuel Cell (SOFC) from the following points of view: a path of alumina particles with high thermal conductivity can be designed as an electrolyte sheet; there are some possibilities that the electrolyte can be enhanced in mechanical strength. As previously reported, these composite materials have higher mechanical strength and better thermal shock resistance than those of YSZ. These composites containing 0-30 wt% of Al[sub 2]O[sub 3] were measured by AC impedance method at temperatures of 250-1,000[degree]C. Electrical conductivities of 8YSZ without Al[sub 2]O[sub 3] and a composite consisting of 80 wt% YSZ and 20 wt%Al[sub 2]O[sub 3] as sintered samples were 1.2 x 10[sup -1]S/cm and 1.0 x 10[sup -1]S/cm respectively at 1,000[degree]C. The ...

1993-01-01

466

Radiation processing of wood-plastic composites  

International Nuclear Information System (INIS)

There are three main types of radiation-processed composite material derived from plastics and fibrous natural polymers. The first are the monomer-impregnated, radiation-treated wood-plastic composites (WPC). They became a commercial success in the early 1970s. More recently, work has focused on improving the WPCs by creating in them interpenetrating network (IPN) systems by the use of appropriate multifunctional oligomers and monomers. The main kinetic features of radiation-initiated chain polymerization remain applicable even in impregnated wood. The second type are the plastics filled or reinforced with dispersed wood fiber or other cellulosics (WFRP). In their case, radiation processing offers a new opportunity to apply radiation-reactive adhesion promoters between wood or cellulosic fibers and the thermoplastic matrices. The third type are the laminar composites made by electron beam coating of wood-based agglomerate ...

467

Preparation of ZrO_2/O'-sialon composites using dissociation of zircon  

International Nuclear Information System (INIS)

ZrO_2/O'-sialon composites were obtained via reaction sintering of ZrSiO_4 and Si_3N_4 powders at about 1700 deg C. Y_2O_3 was effective in both stabilizing of zirconia and densifying the composites. However, it is not easy to select an optimum value of the single additive to balance these two requirements simultaneously. With low Y_2O_3 addition, some tetragonal zirconia grains in the sintered samples are transformable during mechanical grinding but the full densification of the material is then sacrificed. On the other hand, addition more Y_2O_3 to achieve complete densification results in the zirconia being stabilized into undesirable t' or cubic forms. Therefore no improved toughening effects have been achieved in the composites. Heat-treatment of the materials at 1400 deg C. results in the diffusion of yttria from the grain boundary phase to zirconia and the formation of the O'-cubic zirconia ...

468

Metal coordination and selectivity with oxine ligands bound to silica polyamine composites  

British Library Electronic Table of Contents (United Kingdom)

A series of oxine ligands, 5-X, 8 OH C9H6N (X = H, Cl, SO3H) have been covalently bound to a silica gel polyamine composite made from a silanized amorphous silica xerogel and poly(allylamine) (BP-1) by the Mannich reaction. The resulting modified composites WP-4(X = H), CB-1(X = Cl), and SB-1(X = SO3H) were characterized by elemental analysis, FTIR, and solid state CPMAS-13C-NMR. Using the analytical data before and after the ligand modification, the ligand loading could be estimated and in combination with metal ion capacities a metal to ligand ratio could be obtained. The composites WP-4 and CB-1 both showed ratios of approximately 1 : 1 while the sulfonate modified composite, SB-1, showed a metal to ligand ratio of 1 : 2. This is tentatively interpreted in terms of a zwitterionic oxine ...

2010-01-01

469

Influence of Ce0.9Gd0.1O2-d particles on microstructure and oxygen permeability of Ba0.5Sr0.5Co0.8Fe0.2O3-d composite membrane  

British Library Electronic Table of Contents (United Kingdom)

This study examined the oxygen permeation behavior of Ce0.9Gd0.1O2-d (Gadolinium-Doped Ceria, GDC)/Ba0.5Sr0.5Co0.8Fe0.2O3-d (BSCF) composite membranes fabricated using a conventional sintering technique. GDC/BSCF composite membranes with a relative density >95% could be obtained when a green compact of BSCF and GDC was sintered at 1150^oC for 5h. It appears that GDC serves as a grain growth inhibitor because the average grain size of the composite decreased with increasing GDC content. The oxygen permeability of the BSCF and GDC/BSCF composite membranes strongly depends on the grain size and membrane thickness. The addition of GDC to BSCF resulted in a small grain size, low thermal expansion coefficient and high hardness. However, it is believed that oxygen permeation was blocked by GDC, a...

2010-01-01

470

Electron beam processing of rubber wood fibers - polypropylene composites. Effects of reactive additives on the physical and mechanical properties  

International Nuclear Information System (INIS)

The purpose of this study is to determine the suitability of producing agro-fiber reinforced plastic composite (agro-FRPC) from rubber wood fiber blended in polypropylene matrix. The effects of varying fiber dimension and fiber content on the physical and mechanical properties of the composite were evaluated to provide an insight into the fiber matrix adhesion. The effects of reactive additives on the physical and mechanical properties of the composite were evaluated which provides the insight on the reinforcement of the composite. Rubber wood fiber used in this study is currently being used in the manufacturing of medium density fiber (MDF) board. Two sizes of rubber wood fiber were used i.e. 0.5-1.0 mm and 1.0-2.0 mm. Homopolymer polypropylene of MFI 14.0 was used as a matrix. The irradiation work was carried out using electron beam accelerator, 3.0 MeV, 3.0 mA. Various types of reactive additives ...

2000-03-13

471

Electrochemical properties of Si/Ni alloy-graphite composite as an anode material for Li-ion batteries  

International Nuclear Information System (INIS)

Si/Ni alloy and graphite composites were synthesized using arc-melting followed by high energy mechanical milling (HEMM). Alloy particles comprising of NiSi2, NiSi and Si phases were distributed finely and uniformly on the surface of graphite in the composites obtained after Hem. The composite containing 60 wt.% of Si/Ni alloy exhibited a stable capacity of ?780 mAh/g. Fourier transform infrared spectroscopy (FTIR) analysis confirmed that some bonds were formed between alloy and graphite after HEMM, which appeared to retain the electrical connection between alloy and graphite during cycling. X-ray diffraction (XRD) analysis indicated that NiSi2 and NiSi phases, which acted as an inactive alloy matrix remained invariant during charge and discharge. In addition to NiSi2 and NiSi phases, disordered graphite layers also played the role of media for the accommodation of large volume change of Si during cycling. The large ...

2005-09-30

472

Effect of hot air aging on properties of EPDM/SmBO3/EVA and EPDM/ATO/EVA composites  

British Library Electronic Table of Contents (United Kingdom)

Abstract Ethylene-propylene-diene rubber (EPDM)/samarium borate (SmBO3)/ethylene-vinyl acetate (EVA) copolymer and EPDM/antimony-doped tin oxide (ATO)/EVA composites are aged at 150C for different intervals. Surface modification is used to improve filler to matrix interphase. The main aim is to investigate the effect of filler type and vinyl acetate (VA) content in EVA on stability of EPDM composites. It is found that acidic ATO particles can lower pH level of EPDM composites and then promote the degradation of acetic acid during aging. Moreover, when VA content exceeds 14 wt %, the instable VA content causes more acetic acids escape during aging. With the increasing of aging time, EPDM/SmBO3 control and EPDM/SmBO3/EVA composites tend to become darker while EPDM/ATO and EPDM/ATO/EVA compos...

2011-01-01

473

Effect of Al and Be ions pre-implantation on formation and growth of helium bubbles in SiC/SiC composites  

Energy Technology Data Exchange (ETDEWEB)

The effect of Al and Be ions pre-implantation on microstructural change and, the formation and growth of He bubbles in SiC/SiC composite was investigated. Four kinds of ion implanted specimens were prepared with 100 appm Al, 1000 appm Al, 100 appm Be and 1000 appm Be implanted. No microstructural change was observed in the matrices and fibers of SiC/SiC composites implanted with Al or Be ions up to 1000 appm. The un-implanted and Al or Be pre-implanted SiC/SiC composites were simultaneously irradiated to 10 dpa using triple ion-beams (6.0-MeV Si{sup 2+}, 1.0-MeV He{sup +} and 340-keV H{sup +}) at 1000 deg. C. Helium bubbles were formed in every matrix and fiber irradiated by triple ion-beams. The size of He bubbles in the matrix was increased by implanting Al or Be ions and increased with increasing amount of implanted Al or Be ions. The size of He bubbles in the fiber was slightly increased by implanting Al or Be ions. ...

2007-03-15

474

Effect of Al and Be ions pre-implantation on formation and growth of helium bubbles in SiC/SiC composites  

International Nuclear Information System (INIS)

The effect of Al and Be ions pre-implantation on microstructural change and, the formation and growth of He bubbles in SiC/SiC composite was investigated. Four kinds of ion implanted specimens were prepared with 100 appm Al, 1000 appm Al, 100 appm Be and 1000 appm Be implanted. No microstructural change was observed in the matrices and fibers of SiC/SiC composites implanted with Al or Be ions up to 1000 appm. The un-implanted and Al or Be pre-implanted SiC/SiC composites were simultaneously irradiated to 10 dpa using triple ion-beams (6.0-MeV Si"2"+, 1.0-MeV He"+ and 340-keV H"+) at 1000 deg. C. Helium bubbles were formed in every matrix and fiber irradiated by triple ion-beams. The size of He bubbles in the matrix was increased by implanting Al or Be ions and increased with increasing amount of implanted Al or Be ions. The size of He bubbles in the fiber was slightly increased by implanting Al or Be ions. These results ...

2007-03-01

475

Dose effect in the wood plastic composite formation in the presence of additives and co-additives  

Energy Technology Data Exchange (ETDEWEB)

Wood plastic composite (WPC) formation was studied with simul wood and butylmethacrylate (BMA) at different compositions with swelling solvent methanol in the presence of a set of multifunctional acrylate monomer additives like N-vinyl Pyrrolidone (NVP), tripropylene glycol diacrylate (TPGDA) and trimethylol propane triacrylate (TMPTA) at a different doses between 1 and 3 Mrad using Co{sup 60} gamma source. This was further investigated using another set of additives chosen from oligomers such as epoxy acrylate (EA), urethane acrylate (UA) and polyester acrylate (PEA). TMPTA yielded the highest polymer loading at relatively low dose (2 Mrad). Effect of co-additives like sulfuric acid (H{sup +} ions), copper sulphate (Cu{sup 2+} ions) and urea was investigated in these series. Tensile strength (TS) of the composites were determined and the highest TS values were obtained with the composite produced in ...

1994-10-01

476

Characteristics estimation of coal liquefaction residue; Sekitan ekika zansa seijo no suisan ni kansuru kento  

Energy Technology Data Exchange (ETDEWEB)

The paper studied a possibility of estimating characteristics of coal liquefaction residue from liquefaction conditions in the case of fixing coal kind in the NEDOL process coal liquefaction PSU. Wyoming coal was used for the study, and the already proposed simplified liquefaction reaction models were used. Among material balances explained by the models, those of asphaltene, preasphaltene, THF insoluble matters are concerned with residue composition. Ash content is separately calculated from ash balance. Reaction velocity constants of simplified liquefaction reaction models which influence the residue composition were obtained by the multiple regression method from experimental results in the past. The estimation expression of residue viscosity was introduced from residue ash/composition. When the residue composition is estimated by the model from liquefaction conditions, and the residue viscosity is ...

1996-10-28

477

Applications or radiation polymerization hardening to composites  

International Nuclear Information System (INIS)

Comprehensive investigation has been made into the application of the polymerization hardening by radiation, particularly electron beam, to the composites of polymers and other materials. The report is divided into four parts, namely 1) characteristics and problems of the reaction of curing by radiation polymerization, 2) improvement of the bonding capability of high molecular weight materials, 3) bonding by radiation, and 4) composites made by the impregnation and polymerization hardening of monomers. The first part includes the effects of dose rate, temperature rise during the hardening, the peculiarity of electron beam irradiation at high dose rate, reaction environment and additive effects. Main conclusions are as follows: caution must be taken to the amount of residual double bonds because they affect the quality of hardened polymers; the polymerization hardening reaction at high dose rate cannot be analogized by that at low dose rate; and ...

1976-01-01

478

A single amino acid substitution (R441A) in the receptor-binding domain of SARS coronavirus spike protein disrupts the antigenic structure and binding activity  

International Nuclear Information System (INIS)

The spike (S) protein of severe acute respiratory syndrome coronavirus (SARS-CoV) has two major functions: interacting with the receptor to mediate virus entry and inducing protective immunity. Coincidently, the receptor-binding domain (RBD, residues 318-510) of SAR-CoV S protein is a major antigenic site to induce neutralizing antibodies. Here, we used RBD-Fc, a fusion protein containing the RBD and human IgG1 Fc, as a model in the studies and found that a single amino acid substitution in the RBD (R441A) could abolish the immunogenicity of RBD to induce neutralizing antibodies in immunized mice and rabbits. With a panel of anti-RBD mAbs as probes, we observed that R441A substitution was able to disrupt the majority of neutralizing epitopes in the RBD, suggesting that this residue is critical for the antigenic structure responsible for inducing protective immune responses. We also demonstrated that the RBD-Fc bearing R441A mutation could not bind to soluble and cell-associated ...

2006-05-26

479

Structural Investigations of Silica Polyamine Composites: Surface Coverage, Metal Ion Coordination, and Ligand Modification  

Science.gov (United States)

Silanization of the silica gel surface in the synthesis of silica gel polyamine composites uses (chloropropyl)-trichlorosilane (CPTCS). It is possible to substitute a molar fraction of reagent CPTCS with methyltrichlorosilane (MTCS), creating a mixed silane surface layer. Two types of silica gels were modified with a series of MTCS:CPTCS molar ratios. Solid-state CP/MAS 29Si and 13C NMR spectroscopies were used to evaluate the surface silane composition. Surface silane coverage was markedly improved for the resulting gels. When polyamines were grafted to the resultant MTCS:CPTCS silane layers, it was shown that the decrease in the number of propyl attachments to the polyamine resulted in increased quantities of ''free amines''. Optimum MTCS:CPTCS ratios were determined for three polyamines grafted onto one silica gel. A substantial free amine increase was observed for poly(allylamine) (PAA). Metal uptake ...

2006-09-13

480

Structural Investigations of Silica Polyamine Composites: Surface Coverage, Metal Ion Coordination, and Ligand Modification  

Energy Technology Data Exchange (ETDEWEB)

Silanization of the silica gel surface in the synthesis of silica gel polyamine composites uses (chloropropyl)-trichlorosilane (CPTCS). It is possible to substitute a molar fraction of reagent CPTCS with methyltrichlorosilane (MTCS), creating a mixed silane surface layer. Two types of silica gels were modified with a series of MTCS:CPTCS molar ratios. Solid-state CP/MAS 29Si and 13C NMR spectroscopies were used to evaluate the surface silane composition. Surface silane coverage was markedly improved for the resulting gels. When polyamines were grafted to the resultant MTCS:CPTCS silane layers, it was shown that the decrease in the number of propyl attachments to the polyamine resulted in increased quantities of ''free amines''. Optimum MTCS:CPTCS ratios were determined for three polyamines grafted onto one silica gel. A substantial free amine increase was observed for poly(allylamine) (PAA). Metal uptake ...

2006-09-13

481

Effects of matrix resin and fiber content on behavior of fatigue crack propagation in continuous-fiber-mat reinforced CP-resin composites; Renzoku sen`i mat kyoka CP resin fukugozai no hiro kiretsu denpa tokusei ni oyobosu bozai oyobi sen`i gan`yuritsu no eikyo  

Energy Technology Data Exchange (ETDEWEB)

The purpose of the present work is to investigate the effects of matrix resin and fiber content on the behavior of fatigue crack propagation in continuous-glass-fiber-mat reinforced CP-resin composites. For this purpose, ductile matrix resin and brittle one are used. These two kinds of resins have the characteristic that the elastic modulus and tensile strength are nearly the same with each other while the elongation is different. The composite specimens are made of these resins and continuous grass fiber mat of 20 wt.% and 60 wt% fiber contents. The fatigue crack propagation test was conducted by using the tapered DCB specimens to control the stress intensity factor range, {delta}K, during the test. The results obtained are as follows; (1) The relation between the crack propagation rate, da/dN, and {delta}K for all the present materials is shown by a straight line in logarithmic representation. (2) For the composites of 20 ...

1996-05-15

482

The evaporation pan technique revisited: Old theory and a new application for time-weighted synoptic tracing of the isotopic composition of atmospheric vapour  

International Nuclear Information System (INIS)

Reliable and consistent characterization of the stable isotope composition of atmospheric water vapour and its temporal variability are important prerequisites to the wider application of isotope mass balance methods in atmospheric and water balance studies. A new approach is proposed which utilizes standard class-A evaporation pans, which have sufficient volume to buffer short-term transient variations in atmospheric conditions, justifying the assumption of constant kinetic isotopic fractionation effects in concert with precisely measured temperature and relative humidity to derive vapour isotopic composition. The results of the studies suggest that isotopic sampling of existing, conventionally operated class-A evaporation pans could offer a straightforward and cost-effective solution to the problem of documenting the shifting isotopic distribution in atmospheric moisture

1999-12-01

483

Study on polyamide thin-film composite nanofiltration membrane by interfacial polymerization of polyvinylamine (PVAm) and isophthaloyl chloride (IPC)  

British Library Electronic Table of Contents (United Kingdom)

A novel thin-film composite polyamide nanofiltration membrane was prepared through interfacial polymerization of polymeric polyamine polyvinylamine (PVAm) with isophthaloyl chloride (IPC) on a polysulfone supporting film. The composite membranes were prepared under different conditions and characterized in terms of chemical and morphological structures, surface zeta potential, pure water permeability, and rejection to different solutes including electrolytes and sucrose. The results showed that the membrane performance was significantly affected by the content of amine units of PVAm and the concentrations of PVAm and IPC. The increase of the content of amine units of PVAm and the concentration of IPC resulted in an augment in salt rejection and a decrease in permeability, while the increas...

2011-01-01

484

Silica Polyamine Composites: New Supramolecular Materials for Cation and Anion Recovery and Remediation  

British Library Electronic Table of Contents (United Kingdom)

Summary: The surface coverage of amorphous silica gels used in the synthesis of silica polyamine composites has been investigated by 29Si NMR. By diluting the polyamine anchor silane, chloropropyl trichlorosilane, with methyl trichlorosilane it was found that surface coverage could be markedly improved for a range of amine polymers after grafting to the silica surface. The commensurate decrease in the number of anchor points and increase in the number of free amines results in an increase in metal capacity and/or an improvement in capture kinetics. Solid state CPMAS-13C NMR has been employed to investigate the structure and metal ion binding of a series of these composite materials. It is reported that the highly branched polymer, poly(ethyleneimine) (PEI) exhibits much broader 13C NMR res...

2006-01-01

485

Seasonal variations in biochemical composition of Sepia officinalis (Mollusca) from the Mediterranean waters off Alexandria, Egypt  

Energy Technology Data Exchange (ETDEWEB)

The biochemical compositions of 465 Sepia officinalis mantles from the Mediterranean waters off Alexandria Egypt, were studied from September 1989 to August 1990. Water contents of males and females were not significantly different, and followed the same pattern showing a sharp decrease in summer. Lipid contents of males and females were similar, showing two peaks in summer and autumn. A clear reverse relationship between water and lipid contents was found. Protein and ash contents showed irregular patterns. Protein contents were increased in early spring and mid-summer. The relationship between body compositions and mantle size, gonads maturation and environmental conditions was discussed.

1995-12-31

486

Scope and dissolution studies and characterization of irradiated nuclear fuel in Atalante Hot Cell Facilities (abstract and presentation slides)  

Energy Technology Data Exchange (ETDEWEB)

Since 1999, several studies on nuclear fuels were realised in C11/C12 Atalante Hot Cell. This paper presents firstly an overview of the apparatus used for fuel dissolution and characterisation like reactor design, gas trapping flask and solid/liquid separation. Then, the general methodology is described as a function of fuel, temperature, reagents, showing for each step, the reachable experimental data: Dissolution rate, chemical and radiochemical fuel composition including volatile LLRN, insoluble mass, composition, morphology, cladding chemical, radiochemical and physical characterisation using SIMS (made in Cadarache/LECA facilities), MEB. To conclude, some of the obtained results on 129I and 14C composition of oxide fuels, rate of dissolution and first results on dissolution studies of RERTR UMo fuel will be detailed. (Author)

2005-01-01

487

PIXE analysis of chinese chicken-blood stone  

Energy Technology Data Exchange (ETDEWEB)

This paper reports the chemical compositions of chicken-blood stone Ji Xue Shi measured by Proton Induced X-ray Emission (PIXE). The experimental result show that for the red portion of chicken-blood stone, the concentration of Hg is as high as 20 wt%, and the concentration of S can be above 10 wt%. For the non-red portion the main chemical compositions are Al{sub 2}O{sub 3} and SiO{sub 2}. The obtained chemical compositions are close to those of kaolinite for Balin chicken-blood stone, and of pyrophyllite for Changhua chicken-blood stone, respectively. So far many Changhua chicken-blood stones and Balin chicken-blood stones were found in China, the PIXE method can be used to explore the provenance of available chicken-blood stones. (author)

1999-07-01

488

One-step synthesis of reduced graphite oxide-silver nanocomposite  

British Library Electronic Table of Contents (United Kingdom)

Here, a general approach for the preparation of reduced graphite oxide (rGO)-silver nanocomposite has been investigated. Graphite oxide (GO) sheets are used as the nanoscale substrates for the formation of rGO-silver composite. GO sheets and Ag ions can be reduced at the same time, under a mild condition using l-ascorbic acid (l-AA) as reducing agent. This simple approach should find practical applications in the production of rGO-silver nanocomposite. The SEM analysis indicates that the silver particles are dispersed on graphene sheets. Raman signals of rGO in the composite are increased by the attached silver nanoparticles, displaying surface-enhanced Raman scattering activity. The degree of enhancement can be adjusted by varying the quantity of silver nanoparticles in the composite. In ...

2011-01-01

489

New trends in phospholipid class composition of marine sponges  

British Library Electronic Table of Contents (United Kingdom)

The exceptional ability of marine sponges to adapt to often drastic changes of their environments could be due to special structural features in cell membranes, including firstly phospholipids (PL). Thus, PL class composition was investigated in marine sponges (22 species from 19 genera to 15 families) originating from various locations (East Atlantic, North Atlantic, South-West Pacific, Mediterranean Sea, Red Sea, Arabian?Persian Gulf). The quantitative determination of PL class composition was obtained by high-performance thin-layer chromatography (HPTLC) with scanning densitometry of the different spots. Previous reports have shown phosphatidylethanolamine (PE) as the major PL class in marine sponges, followed by phosphatidylcholine (PC), while other papers described PC as a minor class...

2008-01-01

490

New sealant for nuclear power station premises of emergency location  

International Nuclear Information System (INIS)

When operating a nuclear power plant the necessity arise to eliminate various defects of building constructions, to seal joints and transitional elements. The authors present data concerning the production of a sealing composition made of epoxy resin and used for NPP premises of emergency location. Analytical relations are presented between the properties of the composition (adhesion strength, water absorption and others) and its structure. Physical, mechanical and thermal properties and structural peculiarities are determined in the process of interaction between the filling and binding agents. The composition sustains sealing properties under environmental conditions at he presence of an air - vapour mixture with 160 degrees C"o temperature and 0.3 MPa surplus pressure. (author).

491

Magnetic and magnetostrictive properties of manganese substituted cobalt ferrite  

International Nuclear Information System (INIS)

The magnetic and magnetostrictive properties of polycrystalline Co1-xMnxFe2O4 (0 ? x ? 0.4) have been studied. Although the Curie temperature decreases continuously with increasing concentration of Mn, the magnetization remains high up to x = 0.3 and unexpectedly low coercivity is observed for this composition showing an unusual magnetostrictive behaviour. This composition shows a relatively larger magnetostriction at low fields. Moreover, the strain derivative which is the slope of the magnetostriction curve at low magnetic fields is almost doubled and the field at which maximum magnetostriction is observed is reduced to almost half for 30% of Mn substitution. The results show that x ? 0.3 in Co1-xMnxFe2O4 is an optimum composition with superior magnetostrictive properties for many applications.

2007-06-07

492

Facesheet debonding criteria for composite sandwich panels under in-plane compression  

Science.gov (United States)

A method for determining the critical debond size between the facesheet and the core in composite sandwich panels under in-plane compression is described. The approach uses fracture mechanics together with a buckling criterion for a debonded faceskin. The technique yields predictions for the critical in-plane compressive load for debond propagation as a function of core-to-faceskin debond size, faceskin thickness, lay-up, composite material properties, and honeycomb properties and geometry. A computer program, developed in this work, calculates the critical buckling load and facesheet deformed shape by solving an eigenvalue problem. The output predicts, for several cases, critical initial debond lengths comparable to those that have been observed on tests on sandwich panels.

1992-07-01

493

Experimental study on simultaneous desulfurization and denitrification from flue gas with composite absorbent  

British Library Electronic Table of Contents (United Kingdom)

Abstract The characteristics of desulfurization and denitrification with composite absorbent were researched through aqueous absorption experiments. The removal efficiencies of SO2 and NO were up to 100 and 95%, respectively. The composite absorbent included NaClO2 and component M. Existence of component M in the solution could reduce the absorbent cost compared with using sodium chlorite alone. Chlorine dioxide, as main reaction intermediate product, participated in oxidation reaction. The optimal experimental conditions involved NaClO2 concentration of1.13 mmol/L, solution pH of 5.5, molar ratio (M/NaClO2) of 4.1, reaction temperature of 323 K. The optimal solution pH and reaction temperature were both in the required ranges of limestone-gypsum wet flue gas desulfurization (FGD) process....

2011-01-01

494

Effects of carbon fiber surface treatment on the tribological properties of 2D woven carbon fabric/polyimide composites  

British Library Electronic Table of Contents (United Kingdom)

Polyacrylonitrile (PAN)-based carbon fabric (CF) was modified with strong HNO3 oxidation and then introduced into polyimide (PI) composites. The friction and wear properties of the carbon fabric reinforced polyimide composites (CFRP), sliding against GCr15 stainless steel rings, were investigated on an M-2000 model ring-on-block test rig under dry sliding. Experimental results revealed that the carbon fiber surface treatment largely reduced the friction and wear of the CFRP. Compared with the untreated ones, the surface-modified CF can enhance the tribological properties of CFRP efficiently due to the improved adhesion between the CF and the PI matrix. Scanning electron microscope (SEM) and X-ray photoelectron spectroscopy (XPS) study of the carbon fiber surface showed that the fiber surfa...

2009-01-01

495

Effect of carbon fibers surface treatment on tribological performance of polyurethane (PU) composite coating  

British Library Electronic Table of Contents (United Kingdom)

The carbon fibers (CF) were pre-treated in two different ways: no pre-treatment, and activation in HNO3 plus application of toluene-2,4-diisocyanate (TDI). Carbon fibers have been introduced into polyurethane (PU) composite coatings. The tribological behaviors of the polyurethane composite coating filled with CF or TDI-modified CF (TDI-CF) were studied using a ring-on-block wear tester under dry sliding, and the worn surfaces of the filled PU coatings and transfer films formed on the surface of the counterpart ring sliding against the PU coating were investigated by SEM and optical microscope (OM), respectively. Owing to the effective improvement of the interfacial adhesion between the CF and polyurethane matrix, compared with the cases of untreated CF, the employment of low content TDI-CF...

2008-01-01

496

Effect of Coating of Ammonium Perchlorate with Fluorocarbon on Ballistic and Sensitivity Properties of AP/Al/HTPB Propellant  

British Library Electronic Table of Contents (United Kingdom)

Fluorocarbon polymers are used to enhance thermal stability and electrostatic protection of composite propellant compositions. A precipitation technique has been developed to coat ammonium perchlorate (AP) using a copolymer of hexafluoropropylene and vinylidene fluoride (HFP-VF) with the help of solvent-counter solvent method. The coated AP has been used to prepare propellant compositions in different ratio based on hydroxyl terminated polybutadiene (HTPB), aluminium powder along with uncoated AP and studied for viscosity build-up and visco-elastic behaviour as well as mechanical, ballistic, thermal and sensitivity properties keeping 86% solid loading. The data on viscosity build-up indicate that as the percentage of viton coated AP increases end of mix viscosity and viscosity build-up inc...

2009-01-01

497

Conventional power system stabilizer with auxiliary self tuning/fixed-parameter controller  

Energy Technology Data Exchange (ETDEWEB)

In this paper the concept of a composite power system stabilizer is investigated. This stabilizer comprises a properly designed, robust, conventional power system stabilizer (CPSS) and an auxiliary stabilizer (AS) which can be either a self-tuning stabilizer (ASTS) or a fixed-parameter stabilizer (AFPS). For small disturbances, the CPSS performs satisfactorily over a wide range of operating conditions. When large disturbances occur the auxiliary stabilizer augments the performance of the CPSS. It has been demonstrated that the composite power system stabilizer can significantly improve the dynamic performance of the system when there is a major disturbance such as a short circuit in the system. Because in the case of a single-machine system the parameters of the ASTS do not vary appreciably, it can also be implemented as a fixed-parameter device; this simplifies significantly the implementation of the composite PSS. ...

1995-02-01

498

Characterization of the combustion of biomass producer gas in a constant volume combustion bomb  

British Library Electronic Table of Contents (United Kingdom)

In this article a methodology is presented for studying the influence of the biomass moisture content and the biomass/air ratio on the producer gas composition and on the chemiluminescent emissions during the combustion process. Firstly, a mathematical model based on the thermo-chemical processes inside the gasifier is used to predict the composition of the producer gas as a mixture of CO, CO2, H2, N2, CH4 and H2O gases. Secondly, the predicted composition is introduced into a constant volume combustion bomb (CVCB), which simulates the typical conditions inside the combustion chamber of an internal combustion engine, in order to characterize its combustion under gasoline-type conditions through the instantaneous pressure and the detection of the spontaneous luminous radiation (chemilumines...

2010-01-01

499

Cellulose and cellulignin from sugarcane bagasse reinforced polypropylene composites: Effect of acetylation on mechanical and thermal properties  

British Library Electronic Table of Contents (United Kingdom)

This current work is concerned with the development of polypropylene composites reinforced with cellulose and cellulignin fibers attained from sugarcane bagasse. Moreover, the fibers were chemically modified by acetylating process and its effects on the fiber/matrix interaction were also evaluated. The chemical modification efficiency was verified by FTIR analysis and the fibers morphological aspects of fibers by SEM. Likewise, the influence of modified fibers content in the composites was studied by mechanical (tensile, shear and flexural tests) and thermal analyses (TGA and DSC). After the chemical modification, the FTIR results showed the appearance of acetyl groups and reduction of OH bonds for all fibers. Together with, SEM characterization showed that the acetylation changed the morp...

2008-01-01

500

Advanced experimental design applied to damage tolerance of composite materials  

Science.gov (United States)

This paper focuses on a factorial-based design strategy. The approach provides an efficient and statistically reliable means for assessing the influence of multivariable effects. It is applied to the detection and evaluation of damage in impacted composite sandwich panels. The experimental results obtained from this test strategy are utilized to form an empirical response function. The resulting polynomial relates damage area to residual compression strength at values of independent variables for which testing did not occur. The response function also identifies nonlinear interaction effects of key variabes that cannot be easily ascertained by traditional single-variable test strategies. Independent variables evaluated include core thickness, number of face sheet plys and impact energy. The methodology presented allows the designer to predict with more confidence the damage tolerance of a composite material component, and the analyst to more ...

1991-01-01