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Conflicts in Chemistry: The Case of Plastics, a Role-Playing Game for High School Chemistry Students

Science.gov (United States)

Cook, Deborah H.

2014-01-01

Conflicts in Chemistry: The Case of Plastics, an innovative role-playing activity for high school students, was developed by the Chemical Heritage Foundation to promote increased public understanding of chemistry. The pilot program included three high school teachers and their students at three different schools and documented implementation and…
Combinatorial chemistry approach to development of molecular plastic solar cells

NARCIS (Netherlands)

Godovsky, Dmitri; Inganäs, Olle; Brabec, Christoph J.; Sariciftci, N. Serdar; Hummelen, Jan C.; Janssen, Rene A.J.; Prato, M.; Maggini, M.; Segura, Jose; Martin, Nazario

1999-01-01

We used a combinatorial chemistry approach to develop the molecular plastic solar cells based on soluble fullerene derivatives or solubilized TCNQ molecules in combination with conjugated polymers. Profiles, formed by the diffusion of low molecular weight component in the spin-cast polymer host were
Radiation chemistry of plastic crystals. Annual progress report, November 1, 1976--October 31, 1977

International Nuclear Information System (INIS)

Klingen, T.J.

1977-01-01

The overall purpose of this investigation is the understanding of the role that mesomorphism plays in the radiation chemistry of plastic crystals. In approaching this problem, the first step is to obtain data on the basic radiation chemistry of the most ordered solid state--the crystalline state. Thus, the results reported here are concerned with determination of the radiolysis of three plastic crystals in their highest ordered state. In addition to these studies, investigation of the optical properties and the positron life time properties of these materials in their plastic crystalline state was undertaken. The primary purpose of these studies during the current reporting period was the determination of the feasibility of these techniques to provide useful information to the overall project goal
Progress report on nuclear science and technology in China (Vol.3). Proceedings of academic annual meeting of China Nuclear Society in 2013, No.4--Nuclear chemistry and radiation chemistry sub-volume

International Nuclear Information System (INIS)

2014-05-01

Progress report on nuclear science and technology in China (Vol. 3) includes 24 articles which are communicated on the third national academic annual meeting of China Nuclear Society. There are 10 books totally. This is the fourth one, the content is about Nuclear chemistry and radiation chemistry sub-volume
Research on condensed matter and atomic physics using major experimental facilities and devices: Physics, chemistry, biology. Reports on results. Vol. 3. 4. Chemistry. 5. Biology. 6. Development of methods and instruments

International Nuclear Information System (INIS)

1993-01-01

This report in three volumes substantiates the contents of the programme survey published in September 1989. The progress reports cover the following research areas: Vol. I, (1). Atomic and molecular physics - free atoms, molecules, macromolecules, clusters, matrix-isolated atoms and molecules. (2) Physics and chemistry of surfaces and interfaces - epitaxy, surface structure, adsorption, electrical, magnetic, and optical properties, thin films, synthetic layer structure. Vol. II, (3). Solid-state physics, and materials science -structural research, lattice dynamics, magnetic structure and dynamics, electronic states; load; spin and pulse density fluctuations; diffusion and internal motion, defects, unordered systems and liquids. Vol. III, (4). Chemistry - bonding and structure, kinetics and reaction mechanisms, polymer research, analysis and synthesis. (5). Biology, - structure and dynamics of biological macromolecules, membrane and cell biology. (6) Development of methods and instruments - neutron sources, synchrotron sources, special accelerators, research with interlinked systems and devices. (orig.) [de
Possible Role of Green Chemistry in Addressing Environmenal Plastic Debris: Scientific, Economic and Policy Issues

Science.gov (United States)

Bayha, K. M.

2016-02-01

Plastics have revolutionized modern life, replacing other raw materials in a vast array of products, due to their ease in molding and shaping, as well as superior recalcitrance to wearing and aging. However, this functional benefit makes plastic one of the most problematic pollutants, since they accumulate as environmental debris for decades and possibly for centuries. Rightfully so, programs addressing plastic debris typically involve efforts to reduce consumption, reuse plastic products and recycle them when usefulness is complete. However, some of these options can be problematic for certain applications, as well as in countries that lack efficient municipal solid waste or recycling facilities. The principles of Green Chemistry were developed to help scientists design chemical products that reduce or eliminate the use or generation of hazardous substances. These principles have also been applied to developing sustainable or greener polymers for use in consumer plastics. For instance, the EPA's Green Chemistry Program awards the Presidential Green Chemistry Challenge Awards each year, with a large percentage of awards having gone to developments in greener polymers. Many of these advancements involve the development of sustainable bio-based, more degradable or more recyclable polymers that deliver significant environmental benefits. This presentation is meant to address what role the development of truly greener polymers might have in addressing environmental plastic debris in parallel with efforts to reduce, reuse and recycle. The intention is to evaluate the issues posed by traditional polymer types, address the ultimate goals of alternative polymer development and evaluate research on current alternative polymer technologies, in order to objectively assess their usefulness in addressing environmental plastic debris accumulation. In addition, the scientific, policy and market issues that may be impeding accurate development, evaluation and implementation of
Research on condensed matter and atomic physics, using major experimental facilities and devices: Physics, chemistry, biology. Reports on results. Vol. 1. 1. Atomic and molecular physics. 2. Physics and chemistry of surfaces and interfaces

International Nuclear Information System (INIS)

1993-01-01

This report in three volumes substantiates the contents of the programme survey published in September 1989. The progress reports cover the following research areas: Vol. I, (1). Atomic and molecular physics - free atoms, molecules, macromolecules, clusters, matrix-isolated atoms and molecules. (2) Physics and chemistry of surfaces and interfaces - epitaxy, surface structure, adsorption, electrical, magnetic, and optical properties, thin films, synthetic layer structure. Vol. II, (3). Solid-state physics, and materials science -structural research, lattice dynamics, magnetic structure and dynamics, electronic states; load; spin and pulse density fluctuations; diffusion and internal motion, defects, unordered systems and liquids. Vol. III, (4). Chemistry - bonding and structure, kinetics and reaction mechanisms, polymer research, analysis and synthesis. (5). Biology, - structure and dynamics of biological macromolecules, membrane and cell biology. (6) Development of methods and instruments - neutron sources, synchrotron sources, special accelerators, research with interlinked systems and devices. (orig.) [de
Radiation chemistry of plastic crystals. Final report

International Nuclear Information System (INIS)

Klingen, T.J.

1979-01-01

The primary purpose of this report is to summarize the research done under this contract over the past twelve years. Since it is manifestly impossible to provide all the details involved in this work in this report only the primary results of these studies are discussed. The detailed radiolytic mechanisms and kinetics, as well as other detailed information on the systems studied have previously been reported in the annual reports, ORO-3781-1 through 14 and in the journal articles listed in the Contract Publications section of this report. The initial purpose of this work was to study the gamma-ray induced polymerization of organo-substituted carboranes in the solid state. With time this purpose changed to understanding in detail the effects plastic crystallinity had on the overall radiolysis of materials in this type of mesomorphic state. This work included the effects of phase, charge transfer, organic substituent and the ability of the carboranes to act as electron scavengers. For clarity of presentation, the work in the various areas which was performed under this contract is reported in four separate sections: plastic crystallinity, radiation chemistry, electrooptical properties, and thermal oligomerization
Effects of wood fiber surface chemistry on strength of wood–plastic composites

Energy Technology Data Exchange (ETDEWEB)

Migneault, Sébastien, E-mail: sebastien.migneault@uqat.ca [University of Quebec in Abitibi-Temiscamingue (UQAT), 445 boulevard de l’Université, Rouyn-Noranda, Québec J9X 5E4 (Canada); Koubaa, Ahmed, E-mail: ahmed.koubaa@uqat.ca [UQAT (Canada); Perré, Patrick, E-mail: patrick.perre@ecp.fr [École centrale de Paris, Grande Voie des Vignes, F-92 295 Chatenay-Malabry Cedex (France); Riedl, Bernard, E-mail: Bernard.Riedl@sbf.ulaval.ca [Université Laval, 2425 rue de la Terrasse, Québec City, Québec G1V 0A6 (Canada)

2015-07-15

Highlights: • Infrared spectroscopy and X-ray photoelectron spectroscopy analyses showed variations of surface chemical characteristics according to fiber origin. • Surface chemical characteristics of fibers could partly explain the differences in mechanical properties of the wood–plastic composites. • Fibers with carbohydrate rich surface led to stronger wood–plastic composites because the coupling between the matrix and fibers using coupling agent is achieved with polar sites mostly available on carbohydrates. • Conversely, lignin or extractives rich surface do not have oxidized functions for the esterification reaction with coupling agent and thus led to wood–plastic composites with lower mechanical properties. • Other factors such as mechanical interlocking and fiber morphology interfere with the effects of fiber surface chemistry. - Abstract: Because wood–plastic composites (WPC) strength relies on fiber-matrix interaction at fiber surface, it is likely that fiber surface chemistry plays an important role in WPC strength development. The objective of the present study is to investigate the relationships between fiber surface chemical characteristics and WPC mechanical properties. Different fibers were selected and characterized for surface chemical characteristics using X-ray photoelectron spectroscopy (XPS) and infrared spectroscopy (FTIR). WPC samples were manufactured at 40% fiber content and with six different fibers. High density polyethylene was used as matrix and maleated polyethylene (MAPE) was used as compatibility agent. WPC samples were tested for mechanical properties and fiber-matrix interface was observed with scanning electron microscope. It was found WPC strength decreases as the amount of unoxidized carbon (assigned to lignin and extractives) measured with XPS on fiber surface increases. In the opposite case, WPC strength increases with increasing level of oxidized carbon (assigned to carbohydrates) on fiber surface. The same
Effects of wood fiber surface chemistry on strength of wood–plastic composites

International Nuclear Information System (INIS)

Migneault, Sébastien; Koubaa, Ahmed; Perré, Patrick; Riedl, Bernard

2015-01-01

Highlights: • Infrared spectroscopy and X-ray photoelectron spectroscopy analyses showed variations of surface chemical characteristics according to fiber origin. • Surface chemical characteristics of fibers could partly explain the differences in mechanical properties of the wood–plastic composites. • Fibers with carbohydrate rich surface led to stronger wood–plastic composites because the coupling between the matrix and fibers using coupling agent is achieved with polar sites mostly available on carbohydrates. • Conversely, lignin or extractives rich surface do not have oxidized functions for the esterification reaction with coupling agent and thus led to wood–plastic composites with lower mechanical properties. • Other factors such as mechanical interlocking and fiber morphology interfere with the effects of fiber surface chemistry. - Abstract: Because wood–plastic composites (WPC) strength relies on fiber-matrix interaction at fiber surface, it is likely that fiber surface chemistry plays an important role in WPC strength development. The objective of the present study is to investigate the relationships between fiber surface chemical characteristics and WPC mechanical properties. Different fibers were selected and characterized for surface chemical characteristics using X-ray photoelectron spectroscopy (XPS) and infrared spectroscopy (FTIR). WPC samples were manufactured at 40% fiber content and with six different fibers. High density polyethylene was used as matrix and maleated polyethylene (MAPE) was used as compatibility agent. WPC samples were tested for mechanical properties and fiber-matrix interface was observed with scanning electron microscope. It was found WPC strength decreases as the amount of unoxidized carbon (assigned to lignin and extractives) measured with XPS on fiber surface increases. In the opposite case, WPC strength increases with increasing level of oxidized carbon (assigned to carbohydrates) on fiber surface. The same
51. Meeting of the Chemical Societies: Almanac of Contributions, Vol. Program, 1, 2, 3, 4 Molecular Models (Workshop)

International Nuclear Information System (INIS)

Uher, M.; Benes, P.; Carsky, J.; Ctrnactova, H.; Fecenko, J.; Fellner, P.; Hodul, P.; Koprda, V.; Kratochvil, B.; Krkoska, P.; Kuruc, J.; Lehotay, J.; Matousek, J.; Milichovsky, P.; Omastova, M.; Petrus, L. jr.; Petrus, L. sr.; Schwendt, P.; Silny, P.; Sevcik, P.; Toma, S.; Uherova, R.; Zachar, P.

1999-09-01

The publication has been set up as a abstracts of the meeting dealing with different chemical problems. The book (Vol. 1) consists of the sections: All-plenary lectures (9 papers); (D) History of the chemistry (14); (K) Didactics of chemistry (32); The book (Vol. 2) consists of the sections: (A) Analytical chemistry (48); (B) Inorganic chemistry (75); (C) Physical chemistry (27); (F) Nuclear chemistry and radioecology (12); (L) Environmental chemistry and toxicology (33); (M) Agricultural chemistry (20). The book (Vol. 3) consists of the sections: (E) Wood, pulp, paper (15); (G) Macromolecular chemistry (42); (H) Organic chemistry, bio-organic chemistry and pharmaceutical chemistry (96); (I) Food chemistry and biochemistry (34); (J) Textile, fibres and foil materials (9). The book (Vol. 4) consists of the workshop Molecular models (3 papers)
Plastic

International Nuclear Information System (INIS)

Jeong Gi Hyeon

1987-04-01

This book deals with plastic, which includes introduction for plastic, chemistry of high polymers, polymerization, speciality and structure of a high molecule property of plastic, molding, thermosetting plastic, such as polyethylene, polyether, polyamide and polyvinyl acetyl, thermal plastic like phenolic resins, xylene resins, melamine resin, epoxy resin, alkyd resin and poly urethan resin, new plastic like ionomer and PPS resin, synthetic laminated tape and synthetic wood, mixed materials in plastic, reprocessing of waste plastic, polymer blend, test method for plastic materials and auxiliary materials of plastic.
Research on condensed matter and atomic physics using major experimental facilities and devices: Physics, chemistry, biology. Reports on results. Vol. 2. 3. Solid state physics and materials science

International Nuclear Information System (INIS)

1993-01-01

This report in three volumes substantiates the contents of the programme survey published in September 1989. The progress reports cover the following research areas: Vol. I, (1). Atomic and molecular physics - free atoms, molecules, macromolecules, clusters, matrix-isolated atoms and molecules. (2) Physics and chemistry of surfaces and interfaces - epitaxy, surface structure, adsorption, electrical, magnetic, and optical properties, thin films, synthetic layer structure. Vol. II, (3). Solid-state physics, and materials science -structural research, lattice dynamics, magnetic structure and dynamics, electronic states; load; spin and pulse density fluctuations; diffusion and internal motion, defects, unordered systems and liquids. Vol. III, (4). Chemistry - bonding and structure, kinetics and reaction mechanisms, polymer research, analysis and synthesis. (5). Biology, - structure and dynamics of biological macromolecules, membrane and cell biology. (6) Development of methods and instruments - neutron sources, synchrotron sources, special accelerators, research with interlinked systems and devices. (orig.) [de
12-EEASA-Vol 22.indd

African Journals Online (AJOL)

jenny

2006-02-22

Feb 22, 2006 ... Southern African Journal of Environmental Education, Vol. .... To this end, a planning conference on environmental .... mathematics, physics, chemistry, biology, geography, agriculture, home economics and human and.
Electrostatics in Chemistry

Indian Academy of Sciences (India)

Electrostatics in Chemistry. 3. Molecular Electrostatic Potential: Visualization and Topography. Shridhar R Gadre and Pravin K Bhadane. 1 1. Basic Principles, Resona- nce, Vol.4, No.2, 11-19, 1999. 2. Electrostatic Potentials of. Atoms, Ions and Molecules,. Resonance, Vol.4, No.5, 40-51,. 1999. Topographical features of the ...
An Example of Learning about Plastics and Their Evaluation as a Contribution to Education for Sustainable Development in Secondary School Chemistry Teaching

Science.gov (United States)

Burmeister, Mareike; Eilks, Ingo

2012-01-01

This paper describes the development and evaluation of a secondary school lesson plan for chemistry education on the topic Education for Sustainable Development (ESD). The lessons focus both on the chemistry of plastics and on learning about the societal evaluation of competing, chemistry-based industrial products. A specific teaching method was…
21 CFR 178.2650 - Organotin stabilizers in vinyl chloride plastics.

Science.gov (United States)

2010-04-01

... extraction tests shall cover at least three equilibrium periodic determinations, as follows: (i) The exposure... Furnace,” Analytical Chemistry, Vol. 49, p. 1090-1093 (1977), which is incorporated by reference. Copies...,” Analytical Chemistry, Vol. 49, pp. 1090-1093 (1977), which is incorporated by reference in accordance with 5...
Filling a Plastic Bag with Carbon Dioxide: A Student-Designed Guided-Inquiry Lab for Advanced Placement and College Chemistry Courses

Science.gov (United States)

Lanni, Laura M.

2014-01-01

A guided-inquiry lab, suitable for first-year general chemistry or high school advanced placement chemistry, is presented that uses only inexpensive, store-bought materials. The reaction of sodium bicarbonate (baking soda) with aqueous acetic acid (vinegar), under the constraint of the challenge to completely fill a sealable plastic bag with the…
49. Meeting of the Chemical Societies: Proceedings of the contributions. Vol. 2

International Nuclear Information System (INIS)

Uher, M.; Benes, P.; Carsky, J.; Chodak, I.; Kuruc, J.; Romancik, V.; Stasko, A. Slovak Technical Univ., Bratislava

1995-09-01

The publication has been set up as a abstracts of the meeting dealing with chemical problems. The book (Vol. 2) consists of the sections: (C) Physical chemistry; (D) History of the chemistry; (E) Food chemistry and technology; (D) Environmental chemistry; (E) Nuclear chemistry and radioecology; (H) Synthetic polymers
Radioanalytical chemistry. Vol. 2

International Nuclear Information System (INIS)

Toelgyessy, J.; Kyrs, M.

1989-01-01

This volume of the monograph covers the following topics: activation analysis, non-activation interaction analysis (elastic scattering of charged particles, absorption and backscattering of beta radiation and photons, radionuclide X-ray fluorescence analysis, thermalization, scattering and absorption of neutrons, use of ionization caused by nuclear radiation, use of ionization by alpha or beta radiation for the measurement of pressure, density and flow rate of gases), and automation in radioanalytical chemistry. (P.A.)

51. Meeting of the Chemical Societies: Almanac of Contributions, Vol. Program, 1, 2, 3, 4 Molecular Models (Workshop); 51. Zjazd chemickych spolocnosti: Zbornik prispevkov, Diel: Program, 1, 2, 3, 4 Molekulove modely (Workshop)

Energy Technology Data Exchange (ETDEWEB)

Uher, M [ed.; Dept. of Org. Chem., Slovak Techn. Univ., Bratislava (Slovakia); Benes, P [ed.; Dept. Nucl. Chem., Czech Techn. Univ., Prague (Czech Republic); Carsky, J [ed.; Inst. of Med. Chem., Biochem. and Clin. Biochem., Comenius Univ., Bratislava (Slovakia); Ctrnactova, H [ed.; Dept. of Educat. and Didactics of Chem., Charles Univ., Prague (Czech Republic); Fecenko, J [ed.; Dept. of Agricult. Chem. and Susten. of Veget., Slovak Agricult. Univ., Nitra (Slovakia); Fellner, P [ed.; Dept. of Inorg. Chem., Slovak Techn. Univ., Bratislava (Slovakia); Hodul, P [ed.; Dept. of Fibres and Textile, Slovak Techn. Univ., Bratislava (Slovakia); Koprda, V [ed.; Dept. of Envir., Slovak Techn. Univ., Bratislava (Slovakia); Kratochvil, B [ed.; Inst. of. Solid State Chem., Chem. Univ., Prague (Czech Republic); Krkoska, P [ed.; Dept. of Chem. Technol. of Wood, Pulp and Paper, Slovak Techn. Univ., Bratislava (Slovakia); Kuruc, J [ed.; Dept. of Nucl. Chem., Comenius Univ., Bratislava (Slovakia); Lehotay, J [ed.; Dept. of Anal. Chem., Slovak Techn. Univ., Bratislava (Slovakia); Matousek, J [ed.; Inst. of Chem. and Technol. of the Envir., Techn. Univ, Brno (Czech Republic); Milichovsky, P [ed.; Dept. of Chem. Techn. of Wood, Pulp and Paper, Univ. Pardubice, Pardubice (Czech Republic); Omastova, M [ed.; Inst. of Polym., SAS, Bratislava (Slovakia); Petrus, L jr; Petrus, L sr [eds.; Inst. of Chem., SAS, Bratislava (Slovakia); Salisova, M [ed.; Dept. of Org. Chem., Comenius Univ., Bratislava (Slovakia); Schwendt, P [ed.; Dept. of Inorg. Chem., Comenius Univ., Bratislava (Slovakia); Silny, P; Sevcik, P; Toma, S [eds.; Comenius Univ., Bratislava (Slovakia); Uherova, R [ed.; Slovak Techn. Univ., Bratislava (Slovakia); Vanek, L [ed.; Charles Univ., Prague (Czech Republic); Zachar, P [ed.; Chem. Univ., Prague (Czech Republic)

1999-09-01

The publication has been set up as a abstracts of the meeting dealing with different chemical problems. The book (Vol. 1) consists of the sections: All-plenary lectures (9 papers); (D) History of the chemistry (14); (K) Didactics of chemistry (32); The book (Vol. 2) consists of the sections: (A) Analytical chemistry (48); (B) Inorganic chemistry (75); (C) Physical chemistry (27); (F) Nuclear chemistry and radioecology (12); (L) Environmental chemistry and toxicology (33); (M) Agricultural chemistry (20). The book (Vol. 3) consists of the sections: (E) Wood, pulp, paper (15); (G) Macromolecular chemistry (42); (H) Organic chemistry, bio-organic chemistry and pharmaceutical chemistry (96); (I) Food chemistry and biochemistry (34); (J) Textile, fibres and foil materials (9). The book (Vol. 4) consists of the workshop Molecular models (3 papers)
Proceedings of the Seventh Conference of Nuclear Sciences and Applications. Vol.1,2,3

International Nuclear Information System (INIS)

Aly, H.F.

2000-01-01

The publication has been set up as a textbook for nuclear sciences and applications vol.1: (1) radiochemistry; (2) radiation chemistry; (3) isotope production; (4) waste management; vol.2: (1) nuclear and reactor; (2) physics; (3) plasma physics; (4) instrumentation and devices; (5) trace and ultra trace analysis; (6) environmental; vol.3: (1) radiation protection; (2) radiation health hazards; (3) nuclear safety; (4) biology; (5) agriculture
Proceedings of the Seventh Conference of Nuclear Sciences and Applications. Vol.1,2,3

Energy Technology Data Exchange (ETDEWEB)

Aly, H F [ed.

2000-07-01

The publication has been set up as a textbook for nuclear sciences and applications vol.1: (1) radiochemistry; (2) radiation chemistry; (3) isotope production; (4) waste management; vol.2: (1) nuclear and reactor; (2) physics; (3) plasma physics; (4) instrumentation and devices; (5) trace and ultra trace analysis; (6) environmental; vol.3: (1) radiation protection; (2) radiation health hazards; (3) nuclear safety; (4) biology; (5) agriculture.
Nigerian Journal of Chemical Research 29 Vol. 15, 2010 ...

African Journals Online (AJOL)

Hp

Nigerian Journal of Chemical Research. 29. Vol. 15, 2010. Antibacterial & Antifungal Studies On Some Coordination Compound Of Metals. With Ampicillin. Pranay Guru. Department of Engineering Chemistry, People's College of Research & Technology, Bhopal. (M. P.) India, email:pranayguru@rediffmail.com. ABSTRACT.
49. Meeting of the Chemical Societies: Proceedings of the contributions. Vol. 2; 49. Zjazd chemickych spolocnosti: Zbornik prispevkov, 2. diel.

Energy Technology Data Exchange (ETDEWEB)

Uher, M [Slovak Technical Univ., Bratislava (Slovakia). Dept. of Organic Chemistry; Hlouskova, Z [Ceska Chemicka Spolecnost, Prague (Czech Republic); Benes, P [Czech Technical University, Prague (Czech Republic). Dept. Nuclear. Chemistry; Carsky, J [Comenius Univ., Bratislava (Slovakia). Inst. of Medicinal Chemistry, Biochemistry and Clinical Biochemistry; Chodak, I [Slovak Academy of Sciences, Bratislava (Slovakia). Polymer Inst.; Kuruc, J [Comenius Univ., Bratislava (Slovakia). Dept. of Nuclear Chemistry; Romancik, V [Ministry of Environment of the Slovak Republic, Bratislava (Slovakia); [Stasko, A. Slovak Technical Univ., Bratislava (Slovakia). Dept. of Physical Chemistry

1996-12-31

The publication has been set up as a abstracts of the meeting dealing with chemical problems. The book (Vol. 2) consists of the sections: (C) Physical chemistry; (D) History of the chemistry; (E) Food chemistry and technology; (D) Environmental chemistry; (E) Nuclear chemistry and radioecology; (H) Synthetic polymers.
Meeting of the Chemical Societies: Almanac of the contributions of the fifty-first meeting of the chemical societies. Vol. 3

International Nuclear Information System (INIS)

Uher, M.; Benes, P.; Carsky, J.; Ctrnactova, H.; Fecenko, J.; Fellner, P.; Hodul, P.; Koprda, V.; Kratochvil, B.; Krkoska, P.; Kuruc, J.; Lehotay, J.; Matousek, J.; Milichovsky, P.; Omastova, M.; Petrus, L. jr.; Petrus, L. sr.; Schwendt, P.; Silny, P.; Sevcik, P.; Toma, S.; Uherova, R.; Zachar, P.

1999-09-01

The publication has been set up as an abstracts of the meeting dealing with different chemical problems. The book (Vol. 3) consists of the sections: (E) Wood, pulp, paper (15 papers); (G) Macromolecular chemistry (42 papers); (H) Organic chemistry, bio-organic chemistry and pharmaceutical chemistry (96 Papers); (I) Food chemistry and biochemistry; (J) Textile, fibres and foil materials
South African Journal of Chemistry

African Journals Online (AJOL)

The journal publishes short communications, full research papers and review articles in all branches of chemistry. Other websites associated with this journal: http://www.journals.co.za/sajchem/. Vol 71 (2018). DOWNLOAD FULL TEXT Open Access DOWNLOAD FULL TEXT Subscription or Fee Access. Table of Contents.
Increasing the Signal to Noise Ratio in a Chemistry Laboratory ...

African Journals Online (AJOL)

Increasing the Signal to Noise Ratio in a Chemistry Laboratory - Improving a Practical for Academic Development Students. ... Analysis of data collected in 2001 shows that the changes made a significant impact on the effectiveness of the laboratory session. South African Journal of Chemistry Vol.56 2003: 47-53 ...
Meeting of the Chemical Societies: Almanac of the contributions of the fifty-third meeting of the chemical societies, Vol. 3

International Nuclear Information System (INIS)

Toelgyessy, J.

2001-09-01

The publication has been set up as the abstracts of the meeting dealing with different chemical problems. The book (Vol. 3) consists of the sections: (F) Chemistry of polymers, organic materials, textile, fibres, foil materials (63 papers); (I) Organic and pharmaceutical chemistry (59 papers); (J) Food chemistry and biotechnology (26 papers); (M) Environment, Toxicology (51 papers)
South African Journal of Chemistry - Vol 56 (2003)

African Journals Online (AJOL)

South African Journal of Chemistry. ... Synthesis and antimicrobial activity of new Thiazole-2(3H)-thiones containing 1, 1, 3-trisubstituted Cyclobutane · EMAIL ... Part 12.1 Fragmentation Patterns in the Electron-impact Mass Spectra of 2-(N, ...
Plastics in Pharmacy and Medicine | McCarthy | South African ...

African Journals Online (AJOL)

South African Medical Journal. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 45, No 1 (1971) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register. Plastics in Pharmacy and Medicine. TJ McCarthy. Abstract.
Premixed flame chemistry of a gasoline primary reference fuel surrogate

KAUST Repository

Selim, Hatem

2017-03-10

Investigating the combustion chemistry of gasoline surrogate fuels promises to improve detailed reaction mechanisms used for simulating their combustion. In this work, the combustion chemistry of one of the simplest, but most frequently used gasoline surrogates – primary reference fuel 84 (PRF 84, 84 vol% iso-octane and 16 vol% n-heptane), has been examined in a stoichiometric premixed laminar flame. Time-of-flight mass spectrometry coupled with a vacuum ultraviolet (VUV) synchrotron light source for species photoionization was used. Reactants, major end-products, stable intermediates, free radicals, and isomeric species were detected and quantified. Numerical simulations were conducted using a detailed chemical kinetic model with the most recently available high temperature sub-mechanisms for iso-octane and heptane, built on the top of an updated pentane isomers model and AramcoMech 2.0 (C0C4) base chemistry. A detailed interpretation of the major differences between the mechanistic pathways of both fuel components is given. A comparison between the experimental and numerical results is depicted and rate of production and sensitivity analyses are shown for the species with considerable disagreement between the experimental and numerical findings.
Industrial applications of radiation chemistry

International Nuclear Information System (INIS)

Puig, Jean Rene

1959-01-01

The status of industrial applications of radiation chemistry as it stands 6 months after the second Geneva international conference is described. The main features of the interaction of ionizing radiations with matter are briefly stated and a review is made of the best studied and the more promising systems of radiation chemistry. The fields of organics, plastics, heterogeneous catalysis are emphasized. Economies of radiation production and utilization are discussed. Reprint of a paper published in Industries atomiques - no. 5-6, 1959
Presidential Green Chemistry Challenge: 2005 Small Business Award

Science.gov (United States)

Presidential Green Chemistry Challenge 2005 award winner, Metabolix, used biotechnology to develop microorganisms that produce polyhydroxyalkanoates: natural, biodegradable plastics with a range of environmental benefits.
Progress report on nuclear science and technology in China (Vol.1). Proceedings of academic annual meeting of China Nuclear Society in 2009, No.4--nuclear material

International Nuclear Information System (INIS)

2010-11-01

Progress report on nuclear science and technology in China (Vol. 1) includes 889 articles which are communicated on the first national academic annual meeting of China Nuclear Society. There are 10 books totally.This is the fourth one, the content is about nuclear materials, isotope separation, nuclear chemistry and radiological chemistry.
Microstructure Evolution and Mechanical Behavior of a Hot-Rolled High-Manganese Dual-Phase Transformation-Induced Plasticity/Twinning-Induced Plasticity Steel

Science.gov (United States)

Fu, Liming; Shan, Mokun; Zhang, Daoda; Wang, Huanrong; Wang, Wei; Shan, Aidang

2017-05-01

The microstructures and deformation behavior were studied in a high-temperature annealed high-manganese dual-phase (28 vol pct δ-ferrite and 72 vol pct γ-austenite) transformation-induced plasticity/twinning-induced plasticity (TRIP/TWIP) steel. The results showed that the steel exhibits a special Lüders-like yielding phenomenon at room temperature (RT) and 348 K (75 °C), while it shows continuous yielding at 423 K, 573 K and 673 K (150 °C, 300 °C and 400 °C) deformation. A significant TRIP effect takes place during Lüders-like deformation at RT and 348 K (75 °C) temperatures. Semiquantitative analysis of the TRIP effect on the Lüders-like yield phenomenon proves that a softening effect of the strain energy consumption of strain-induced transformation is mainly responsible for this Lüders-like phenomenon. The TWIP mechanism dominates the 423 K (150 °C) deformation process, while the dislocation glide controls the plasticity at 573 K (300 °C) deformation. The delta-ferrite, as a hard phase in annealed dual-phase steel, greatly affects the mechanical stability of austenite due to the heterogeneous strain distribution between the two phases during deformation. A delta-ferrite-aided TRIP effect, i.e., martensite transformation induced by localized strain concentration of the hard delta-ferrite, is proposed to explain this kind of Lüders-like phenomenon. Moreover, the tensile curve at RT exhibits an upward curved behavior in the middle deformation stage, which is principally attributed to the deformation twinning of austenite retained after Lüders-like deformation. The combination of the TRIP effect during Lüders-like deformation and the subsequent TWIP effect greatly enhances the ductility in this annealed high-manganese dual-phase TRIP/TWIP steel.
The creep low application for numerical modeling of elastic-plastic flows

Science.gov (United States)

Tyapin, Anatoly; Rudenko, Vladimir; Chekhunov, Evgeny; Shaburov, Michail

1999-06-01

The present paper demonstrates the applicability of Lomnitz logarithm creep law [1] in some approximated version for calculating the elastic-plastic flows. The model has been developed resulting from the intention to have appropriate calculation approximation for particle-velocity -vs-time histories observed in plate 6061-T6 Al samples of various thickness under shock loading and subsequent release and additional compression. The approximation is unique in the whole loading range, from very low to such that elastic precursor is swallowed up by plastic wave . The model is based on Lipkin and Asay [2] remark on scale similarity of the above mentioned particle velocity -vs-time histories for equal shock loading and on approximate equality of velocities that initial portions of release and recompression waves travel at. A Lomnitz creep law presents an ideal phenomenological tool providing both of the requirements be fulfilled at the same time. Its application to high rate processes of loading and release has required some law modification and a nontrivial review of the dislocation mechanism for stress relaxation. The agreement achieved with the experiment is illustrated in figures. The model is worked out and realized in the 1D user software MAG. 1. Lomnitz C. Joun. of Geology, 1956, vol. 64, p. 473-479. 2. Lipkin J., Asay J.R. J. Appl. Phys. ,1977, vol. 48, 1, p.182-189. 3. Johnson J., Barker L. J. Appl. Phys., 1969, vol. 40, 11, p. 4321-4334. 4. Asay J.R., Chhabildas L. M.: Metallurgia., 1984, p. 110-120.
A cohesive plastic/damage-zone model for ductile crack analysis

International Nuclear Information System (INIS)

Zhang, C.; Gross, D.

1995-01-01

A cohesive plastic/damage-zone model of the Dugdale-Barenblatt type (G.I. Barenblatt, Adv. Appl. Mech. 7 (1962) 55-129; D.S. Dugdale, J. Mech. Phys. Solids 8 (1960) 100-104) is presented for analyzing crack growth in ductile materials with damage evolution. A semi-infinite Mode I crack in plane stress or plane stress is considered. The damage is assumed to be present in form of dispersed microvoids which are localized into a narrow strip ahead of the crack-tip. A simple damage model of the Gurson model type (A.L. Gurson, J. Eng. Mater. Technol. 99 (1977) 2-15; V. Tvergaard, Advances in Applied Mechanics, Vol. 27, Academic Press, 1990, pp. 83-151) is developed for uniaxial tension to describe the macroscopic properties of the cohesive plastic/damage-zone. Under small-scale yielding and small-scale damage conditions, a system of nonlinear integral equations for the plastic strain and the length of the cohesive plastic/damage-zone is derived. Numerical results are presented and discussed to reveal the effect of damage evolution on the ductile crack growth. (orig.)
Presidential Green Chemistry Challenge: 2002 Greener Reaction Conditions Award

Science.gov (United States)

Presidential Green Chemistry Challenge 2002 award winner, Cargill Dow, developed the NatureWorks process to make biobased, compostable, and recyclable polylactic acid polymers for fibers and plastic packaging.
Chain Gang-The Chemistry of Polymers (edited by Mickey Sarquis)

Science.gov (United States)

Collard, David M.

1999-01-01

Science in Our World, Vol. 5. Mickey Sarquis, series editor. Terrific Science Press: Middletown, OH, 1995. xiv + 149 pp. ISBN 1-883822-13-0. Spiral-bound, $13.95. Our familiarity with plastics makes polymers ideal examples of chemicals for discussion in K-12 science classes. Most importantly, polymers can be used as examples of chemicals that are safe to handle and of obvious use to society. The structures of polymers are easily represented by a number of models. These simple models go a long way in explaining the familiar physical properties of plastics. However, the introduction of polymers in the classroom relies on the availability of teaching material, experiments, and demonstrations that illustrate concepts in the current science curriculum. Chain Gang-The Chemistry of Polymers, one of the Science in Our World series published by the Center for Chemical Education at Miami University-Middletown (Ohio), will serve as a great resource for teachers interested in providing their students with a series of activities that can be related to their everyday experiences with these ubiquitous chemicals. After a brief introduction to some basic concepts, the book presents a series of 23 experiments. The collection of experiments presented here spans illustrations of chemistry, physical properties, analysis, and processing. Each experiment is recommended as either a hands-on activity or demonstration for various grade levels. A guide for the teacher suggests how the experiment can be used to illustrate topics in the science curriculum. The materials required for each activity are listed in detail, with quantities and sources (all materials are available from Flinn Scientific or hardware stores). There are detailed instructions for preparation of each experiment and how to introduce the experiment to students, and step-by-step instructions for activity. Very importantly, safety and disposal issues are clearly presented. Suggestions for cross-curriculum integration are also

Chemistry with Inexpensive Materials: Spray Bottles and Plastic Bags.

Science.gov (United States)

Zoltewicz, Susan

1993-01-01

Presents eight chemistry activities that are interesting and involve simple, easily available materials. Topics include mystery writing, valentine hearts, flame tests, evaporation race, buoyancy versus mass, determination of relative masses of gases, mole sample container, and cold and hot packs. (DDR)
Presidential Green Chemistry Challenge: 2016 Designing Greener Chemicals and Specific Environmental Benefit: Climate Change Awards

Science.gov (United States)

Presidential Green Chemistry Challenge 2016 award winner, Newlight Technologies, developed a net carbon negative plastic made from methane-based GHG. It is cheaper than petroleum-based plastic; used to make cell phone cases, furniture, and other products.
Modern plastic solar cells : materials, mechanisms and modeling

NARCIS (Netherlands)

Chiechi, Ryan C.; Havenith, Remco W.A.; Hummelen, Jan C.; Koster, L. Jan Anton; Loi, Maria A.

2013-01-01

We provide a short review of modern 'plastic' solar cells, a broad topic that spans materials science, physics, and chemistry. The aim of this review is to provide a primer for non-experts or researchers in related fields who are curious about this rapidly growing field of interdisciplinary
Presidential Green Chemistry Challenge: 2012 Academic Award (Waymouth and Hedrick)

Science.gov (United States)

Presidential Green Chemistry Challenge 2012 award winners, Professor Robert M. Waymouth and Dr. James L. Hedrick, developed a broad class of highly active, environmentally benign, metal-free catalysts for synthesizing plastics.
Vol draadwerk

African Journals Online (AJOL)

Owner

Die motto van Marius Crous se derde bundel,. Vol draadwerk (2012) is ontleen aan die vader van die psigoanalise, Sigmund Freud, wat lui: “Everywhere I go I find a poet has been there before me.” Vol draadwerk verskyn ses jaar ná sy vorige bundel, Aan 'n beentjie sit en kluif. (2006). Vir sy bundel, Brief uit die kolonies ...
Fines Classification Based on Sensitivity to Pore-Fluid Chemistry

KAUST Repository

Jang, Junbong

2015-12-28

The 75-μm particle size is used to discriminate between fine and coarse grains. Further analysis of fine grains is typically based on the plasticity chart. Whereas pore-fluid-chemistry-dependent soil response is a salient and distinguishing characteristic of fine grains, pore-fluid chemistry is not addressed in current classification systems. Liquid limits obtained with electrically contrasting pore fluids (deionized water, 2-M NaCl brine, and kerosene) are combined to define the soil "electrical sensitivity." Liquid limit and electrical sensitivity can be effectively used to classify fine grains according to their fluid-soil response into no-, low-, intermediate-, or high-plasticity fine grains of low, intermediate, or high electrical sensitivity. The proposed methodology benefits from the accumulated experience with liquid limit in the field and addresses the needs of a broader range of geotechnical engineering problems. © ASCE.
Fines classification based on sensitivity to pore-fluid chemistry

Science.gov (United States)

Jang, Junbong; Santamarina, J. Carlos

2016-01-01

The 75-μm particle size is used to discriminate between fine and coarse grains. Further analysis of fine grains is typically based on the plasticity chart. Whereas pore-fluid-chemistry-dependent soil response is a salient and distinguishing characteristic of fine grains, pore-fluid chemistry is not addressed in current classification systems. Liquid limits obtained with electrically contrasting pore fluids (deionized water, 2-M NaCl brine, and kerosene) are combined to define the soil “electrical sensitivity.” Liquid limit and electrical sensitivity can be effectively used to classify fine grains according to their fluid-soil response into no-, low-, intermediate-, or high-plasticity fine grains of low, intermediate, or high electrical sensitivity. The proposed methodology benefits from the accumulated experience with liquid limit in the field and addresses the needs of a broader range of geotechnical engineering problems.
Fines Classification Based on Sensitivity to Pore-Fluid Chemistry

KAUST Repository

Jang, Junbong; Santamarina, Carlos

2015-01-01

The 75-μm particle size is used to discriminate between fine and coarse grains. Further analysis of fine grains is typically based on the plasticity chart. Whereas pore-fluid-chemistry-dependent soil response is a salient and distinguishing
Physical chemistry and the environment

International Nuclear Information System (INIS)

Dunning, T.H. Jr.; Garrett, B.C.; Kolb, C.E. Jr.; Shaw, R.W.; Choppin, G.R.; Wagner, A.F.

1994-08-01

From the ozone hole and the greenhouse effect to plastics recycling and hazardous waste disposal, society faces a number of issues, the solutions to which require an unprecedented understanding of the properties of molecules. We are coming to realize that the environment is a coupled set of chemical systems, its dynamics determining the welfare of the biosphere and of humans in particular. These chemical systems are governed by fundamental molecular interactions, and they present chemists with an unparalleled challenge. The application of current concepts of molecular behavior and of up-to-date experimental and computational techniques can provide us with insights into the environment that are needed to mitigate past damage, to anticipate the impact of current human activity, and to avoid future insults to the environment. Environmental chemistry encompasses a number of separate, yet interlocking, areas of research. In all of these areas progress is limited by an inadequate understanding of the underlying chemical processes involved. Participation of all chemical approaches -- experimental, theoretical and computational -- and of all disciplines of chemistry -- organic, inorganic, physical, analytical and biochemistry -- will be required to provide the necessary fundamental understanding. The Symposium on ''Physical Chemistry and the Environment'' was designed to bring the many exciting and challenging physical chemistry problems involved in environmental chemistry to the attention of a larger segment of the physical chemistry community
Physico-chemical modifications of plastics by ionization

International Nuclear Information System (INIS)

Rouif, S.

2002-01-01

The industrial use of ionizing radiations (beta and gamma), initially for the sterilization of medico-surgical instruments and for the preservation of food products, has led to the development of the chemistry of polymers under radiations. Ionizing radiations can initiate chemical reactions (chain cutting, poly-additions, polymerization etc..) thanks to the formation of free radicals. The main applications concerns the degradation of plastics, the reticulation of plastics and of woods impregnated with resin, and the grafting of polymers. The processing of plastic materials was initially performed with low energy electron accelerators (0.1 to 3 MeV), allowing only surface treatments, while recent high energy accelerators (10 MeV) and gamma facilities allow the treatment in depth of materials (from few cm to 1 m). This article describes the industrial treatments performed with such high energy facilities: 1 - action of ionizing radiations on plastic materials: different types of ionizing radiations, action of beta and gamma radiations, chemical changes induced by beta and gamma radiations; 2 - reticulation of plastic materials submitted to beta and gamma radiations: radio-'reticulable' polymers and reticulation co-agents, modification of the properties of reticulated plastic materials under beta and gamma radiations; 3 - industrial aspects of reticulation under beta and gamma radiation: industrial irradiation facilities, dosimetry and radio-reticulation control, applications; 4 - conclusion. (J.S.)
MATERNAL-FETAL TOLERANCE AS A MANIFESTATION OF REGULATORY CONTINUUM AND PLASTICITY OF THEIR IMMUNE SYSTEMS (in memory of I.P. Ashmarin

Directory of Open Access Journals (Sweden)

E. P. Kharchenko

2011-01-01

Full Text Available Abstract. Relations of immune tolerance between mother and fetus are considered in view of a common regulatory continuum which is formed under the influence of a growing fetus. To explain such an immune tolerance, a notion of immune system plasticity is introduced, as an analogue to the nervous system plasticity, which develops in response to a continuum of changes occurring in fetal and maternal organisms during the nine months of pregnancy. The immune system plasticity in females is supposed to be among possible factors causing collisions upon conception and in the course of pregnancy. (Med. Immunol., 2011, vol. 13, N 2-3, pp 121-132
Biweekly list of papers on radiation chemistry and photochemistry. Annual cumulation with keyword and author indexes. Volume 16. 1983

International Nuclear Information System (INIS)

Carmichael, I.C.; Helman, W.P.; Hug, G.L.; Ross, A.B.

1983-01-01

The Biweekly List of Papers on Radiation Chemistry and Photochemistry is a current-awareness service published by the Radiation Chemistry Data Center (RCDC), with special emphasis on the kinetics and other properties of transient ions, radicals, and excited species. Papers are included on the radiation chemistry and photochemistry of organic and inorganic systems, biological molecules and polymers, with references to ESR and luminescence studies. Complete coverage is attempted only for those studies which are initiated by light or ionizing radiation, and which provide quantitative physical chemical data such as quantum yields, specific rates, G values, etc. No attempt is made to cover topics such as mechanistic and preparative photochemistry, photosynthesis, photography, and irradiation of metals. The references listed herein are obtained from scanning about 60 current journals as well as Chemical Abstracts, INIS Atomindex and several other publications listing current references. The reference lists, which are issued biweekly, are cumulated annually with the addition of keyword and author indexes. Indexed cumulations were published semiannually for Vol. 4-6 (1971-73) and are published annually for Vol. 7+ (1974+); back copies are available from the National Technical Information Service (NTIS)
Use of macroporous plastics in extraction chromatography

International Nuclear Information System (INIS)

Braun, T.; Farac, A.B.

1978-01-01

Possibilities are analysed which the use of porous plastics (polyvinyl chloride, siloxane rubber, polyurethane, polystyrene and etc.) as carriers presents in extraction chromatography. Short characteristics of chemical and physical properties of macroporous carriers is given. The importance of correct chromatographic column packing is noted to obtain columns with good hydrodynamic characteristics and operational properties. Examples of using columns with macroporous carriers in radiochemistry and inorganic chemistry for element separation are given
Correlation between crystallization behaviour and interfacial interactions in plasticized PLA/POSS nanocomposites

Energy Technology Data Exchange (ETDEWEB)

Kodal, Mehmet, E-mail: mehmet.kodal@kocaeli.edu.tr; Şirin, Hümeyra; Özkoç, Güralp, E-mail: guralp.ozkoc@kocaeli.edu.tr [Department of Chemical Engineering, Kocaeli University, 41380, Kocaeli Turkey (Turkey)

2016-03-09

In this study, the correlation between crystallization behavior and surface chemistry of polyhedral oligomeric silsesquioxanes (POSS) for plasticized poly(lactic acid) (PLA)/POSS nanocomposites was investigated. Four different kinds of POSS particles having different chemical structures were used. Poly(ethylene glycol) (PEG, 8000 g/mol) was utilized as the plasticiser. The nanocomposites were melt-compounded in an Xplore Instruments 15 cc twin screw microcompounder at 180°C barrel temperature and 100 rpm screw speed. Non-isothermal crystallization behaviour of PLA/PEG/POSS nanocomposites were evaluated from common kinetic models such as Avrami and Avrami-Ozawa and Kissinger by using the thermal data obtained from differantial scanning calorimetry (DSC). A polarized optical microscope (POM) equipped with a hot-stage was used to examine the morphology during the crystal growth. In order to investigate the interfacial interactions between POSS particles and plasticized PLA, thermodynamic work of adhesion approach was adopted using the experimentally determined surface energies. A strong correlation was obtained between interfacial chemistry and the nucleation rate in plasticized PLA/POSS nanocomposites. It was found that the polar interactions were the dominating factor which determines the nucleation activity of the POSS particles.
Correlation between crystallization behaviour and interfacial interactions in plasticized PLA/POSS nanocomposites

International Nuclear Information System (INIS)

Kodal, Mehmet; Şirin, Hümeyra; Özkoç, Güralp

2016-01-01

In this study, the correlation between crystallization behavior and surface chemistry of polyhedral oligomeric silsesquioxanes (POSS) for plasticized poly(lactic acid) (PLA)/POSS nanocomposites was investigated. Four different kinds of POSS particles having different chemical structures were used. Poly(ethylene glycol) (PEG, 8000 g/mol) was utilized as the plasticiser. The nanocomposites were melt-compounded in an Xplore Instruments 15 cc twin screw microcompounder at 180°C barrel temperature and 100 rpm screw speed. Non-isothermal crystallization behaviour of PLA/PEG/POSS nanocomposites were evaluated from common kinetic models such as Avrami and Avrami-Ozawa and Kissinger by using the thermal data obtained from differantial scanning calorimetry (DSC). A polarized optical microscope (POM) equipped with a hot-stage was used to examine the morphology during the crystal growth. In order to investigate the interfacial interactions between POSS particles and plasticized PLA, thermodynamic work of adhesion approach was adopted using the experimentally determined surface energies. A strong correlation was obtained between interfacial chemistry and the nucleation rate in plasticized PLA/POSS nanocomposites. It was found that the polar interactions were the dominating factor which determines the nucleation activity of the POSS particles.
a study of the physico-chemistry and mineralogy of agbaja clay for ...

African Journals Online (AJOL)

MBI

characterized for particle size distribution, plasticity index, chemical ... m = mass of sample after ignition (g). pH determination. .... the clay must have been of a secondary origin formed from .... The Chemistry and Physics of. Clay and Allied ...
Radiation chemistry and its applications

International Nuclear Information System (INIS)

1968-01-01

In recent years considerable progress has been made in understanding the fundamental chemical reactions that occur when materials are irradiated. This has followed from the development of new techniques for studying these reactions. The International Atomic Energy Agency held a Panel on Radiation Chemistry in Vienna on 17-21 April 1967, to review the current status of various sources, new techniques in radiation chemistry, and their applications. The main sources mentioned by the Panel were isotope sources, electron accelerators, and chemonuclear reactors. Among the basic techniques discussed were pulsed radiolysis, flash photolysis, fast ESR methods, irradiation at liquid helium temperatures, electric discharge methods and far ultra-violet methods. Interesting industrial applications were discussed, such as the development of wood-plastic combinations, and a paper was given on the curing of paints and thin films Refs, figs and tabs
Physico-chemical properties of excavated plastic from landfill mining and current recycling routes

OpenAIRE

Canopoli, Luisa; Fidalgo, Beatriz; Coulon, Frederic; Wagland, Stuart T.

2018-01-01

In Europe over 5.25 billion tonnes of waste has been landfilled between 1995 and 2015. Among this large amount of waste, plastic represents typically 5–25 wt% which is significant and has the potential to be recycled and reintroduced into the circular economy. To date there is still however little information available of the opportunities and challenges in recovering plastics from landfill sites. In this review, the impacts of landfill chemistry on the degradation and/or contamination of exc...
Teaching Chemistry Students How To Use Patent Databases and Glean Patent Information

Science.gov (United States)

MacMillan, Margy; Shaw, Lawton

2008-07-01

Patent literature is an important source of chemical information that is often neglected by chemical educators. This paper describes an effort to teach chemistry students how to use patent databases to search for information on applied chemical technology related to the manufacture of industrial and specialty chemicals. Students in a second-year-level organic chemistry class were shown how to search patent literature as part of a group research paper assignment that involved determining the feasibility of starting an industrial chemical operation to manufacture a given industrial chemical. Students who were assigned high value or specialty chemicals were most likely to cite patent literature in their final papers. Students who were assigned plastics or bulk commodity chemicals were less likely to cite patents. It is suggested that students made choices about the usefulness of patent literature and that patents were most useful when current patents existed and provided the patent owner a competitive advantage. For plastics or commodity chemicals, manufacturing technologies tend to be mature and are well described by more accessible information sources. Suggestions are made for effective introduction of patent literature instruction into upper-level chemistry courses.
Industrial applications of radiation chemistry; Perspectives industrielles de la chimie sous rayonnement

Energy Technology Data Exchange (ETDEWEB)

Puig, Jean Rene [Commissariat a l' energie atomique et aux energies alternatives - CEA, Service de chimie-physique, CEN de Saclay (France)

1959-07-01

The status of industrial applications of radiation chemistry as it stands 6 months after the second Geneva international conference is described. The main features of the interaction of ionizing radiations with matter are briefly stated and a review is made of the best studied and the more promising systems of radiation chemistry. The fields of organics, plastics, heterogeneous catalysis are emphasized. Economies of radiation production and utilization are discussed. Reprint of a paper published in Industries atomiques - no. 5-6, 1959.

GREEN PLASTIC: A NEW PLASTIC FOR PACKAGING

OpenAIRE

Mr. Pankaj Kumar*, Sonia

2016-01-01

This paper gives a brief idea about a new type of plastic called as bio-plastic or green plastic. Plastic is used as a packaging material for various products, but this plastic is made up of non renewable raw materials. There are various disadvantages of using conventional plastic like littering, CO2 production, non-degradable in nature etc. To overcome these problems a new type of plastic is discovered called bio-plastic or green plastic. Bio-plastic is made from renewable resources and also...
An efficient method of material recycling of municipal plastic waste

Czech Academy of Sciences Publication Activity Database

Fortelný, Ivan; Michálková, Danuše; Kruliš, Zdeněk

2004-01-01

Roč. 85, č. 9 (2004), s. 975-979 ISSN 0141-3910. [IUPAC Microsymposium on Degradation, Stabilisation and Recycling of Polymers /42./. Prague, 14.07.2003-17.07.2003] R&D Projects: GA AV ČR(CZ) IBS4050008 Institutional research plan: CEZ:AV0Z4050913 Keywords : recycling * municipal plastic waste * compatibilisation Subject RIV: CD - Macromolecular Chemistry Impact factor: 1.685, year: 2004
Effects of Toxic Leachate from Commercial Plastics on Larval Survival and Settlement of the Barnacle Amphibalanus amphitrite.

Science.gov (United States)

Li, Heng-Xiang; Getzinger, Gordon J; Ferguson, P Lee; Orihuela, Beatriz; Zhu, Mei; Rittschof, Daniel

2016-01-19

Plastic pollution represents a major and growing global problem. It is well-known that plastics are a source of chemical contaminants to the aquatic environment and provide novel habitats for marine organisms. The present study quantified the impacts of plastic leachates from the seven categories of recyclable plastics on larval survival and settlement of barnacle Amphibalanus (=Balanus) amphitrite. Leachates from plastics significantly increased barnacle nauplii mortality at the highest tested concentrations (0.10 and 0.50 m(2)/L). Hydrophobicity (measured as surface energy) was positively correlated with mortality indicating that plastic surface chemistry may be an important factor in the effects of plastics on sessile organisms. Plastic leachates significantly inhibited barnacle cyprids settlement on glass at all tested concentrations. Settlement on plastic surfaces was significantly inhibited after 24 and 48 h, but settlement was not significantly inhibited compared to the controls for some plastics after 72-96 h. In 24 h exposure to seawater, we found larval toxicity and inhibition of settlement with all seven categories of recyclable commercial plastics. Chemical analysis revealed a complex mixture of substances released in plastic leachates. Leaching of toxic compounds from all plastics should be considered when assessing the risks of plastic pollution.
STECH VOL5 (1) FEBRUARY, 2016

African Journals Online (AJOL)

Copyright 1AARR 2012-2016: www.afrrevjo.net

STECH VOL 5 (1) FEBRUARY, 2016. Vol. 5 (1), S/No11, February, 2016: 1-13 ..... Knowledge produce is an act of discovery which involves exploring, analyzing .... Architectural Research, Elsevier: Higher Education Press Limited Company.
Liquid phase solvent bonding of plastic microfluidic devices assisted by retention grooves.

Science.gov (United States)

Wan, Alwin M D; Sadri, Amir; Young, Edmond W K

2015-01-01

We report a novel method for achieving consistent liquid phase solvent bonding of plastic microfluidic devices via the use of retention grooves at the bonding interface. The grooves are patterned during the regular microfabrication process, and can be placed at the periphery of a device, or surrounding microfluidic features with open ports, where they effectively mitigate solvent evaporation, and thus substantially reduce poor bond coverage. This method is broadly applicable to a variety of plastics and solvents, and produces devices with high bond quality (i.e., coverage, strength, and microfeature fidelity) that are suitable for studies in physics, chemistry, and cell biology at the microscale.
Preparation of plastic scintillation detectors and characterization of physico-chemical parameters

International Nuclear Information System (INIS)

Hamada, M.M.; Mesquita, C.H. de

1988-01-01

The development of plastic scintillators for using in the nuclear radiation detection is described. The detectors were fabricated by the polymerization of styrene with organic fluors. The organic fluors used were PPO (1,4 difenil-oxazol) and POPOP 1,4-di-2-(5-fenil-oxazolil) benzene in proportions of 0,5 and 0,05% respectively. Physical-chemistry parameters related to the quality of this detector are investigated at this laboratory. The evaluation of its fluorescency characteristics, density, melting softening, refractive index, molecular weight, gama and alfa espectrometry characteristics and finally the comparative pulse height analysis indicate that the plastic scintillator produced at this laboratory is comparable with others already described. (author) [pt
Basic radiation physics and chemistry of composites

International Nuclear Information System (INIS)

Przybytniak, G.; Zagorski, Z.P.

2006-01-01

Composites are increasingly more important in the applied and fundamental polymer science, and the participation of radiation processing of these systems increase. In presented paper the newest achievements of radiation physics and chemistry of composites are reviewed. It is stressed, that although main experimental effort is directed towards the development of composites as such, and investigation of their specific properties, mechanical, physicochemical and physical, the radiation processing will enter the field on the wider scale, especially as concerns specialized plastics
A Designer Fluid for Aluminum Phase Change Devices, Vol. 1 of 3: General Inorganic Aqueous Solution (IAS) Chemistry

Science.gov (United States)

2016-11-17

out in wicked phase change heat transfer devices. Wen [18] used nanoparticle suspensions to successfully increase the boiling heat transfer...Aqueous Solution of an Anionic Surfactant,” Journal of Heat Transfer 122, No. 4: 708. [18] Wen , D. and Ding, Y., 2005, “Experimental Investigation...Li, Y., 1974, “Diffusion of Ions in Sea Water and in Deep -Sea Sediments,” Geochimica et Cosmochimica Acta, Vol. 88, pp. 703-714. [36] Negishi, K
Plastics, the environment and human health: current consensus and future trends.

Science.gov (United States)

Thompson, Richard C; Moore, Charles J; vom Saal, Frederick S; Swan, Shanna H

2009-07-27

Plastics have transformed everyday life; usage is increasing and annual production is likely to exceed 300 million tonnes by 2010. In this concluding paper to the Theme Issue on Plastics, the Environment and Human Health, we synthesize current understanding of the benefits and concerns surrounding the use of plastics and look to future priorities, challenges and opportunities. It is evident that plastics bring many societal benefits and offer future technological and medical advances. However, concerns about usage and disposal are diverse and include accumulation of waste in landfills and in natural habitats, physical problems for wildlife resulting from ingestion or entanglement in plastic, the leaching of chemicals from plastic products and the potential for plastics to transfer chemicals to wildlife and humans. However, perhaps the most important overriding concern, which is implicit throughout this volume, is that our current usage is not sustainable. Around 4 per cent of world oil production is used as a feedstock to make plastics and a similar amount is used as energy in the process. Yet over a third of current production is used to make items of packaging, which are then rapidly discarded. Given our declining reserves of fossil fuels, and finite capacity for disposal of waste to landfill, this linear use of hydrocarbons, via packaging and other short-lived applications of plastic, is simply not sustainable. There are solutions, including material reduction, design for end-of-life recyclability, increased recycling capacity, development of bio-based feedstocks, strategies to reduce littering, the application of green chemistry life-cycle analyses and revised risk assessment approaches. Such measures will be most effective through the combined actions of the public, industry, scientists and policymakers. There is some urgency, as the quantity of plastics produced in the first 10 years of the current century is likely to approach the quantity produced in the
Plastics, the environment and human health: current consensus and future trends

Science.gov (United States)

Thompson, Richard C.; Moore, Charles J.; vom Saal, Frederick S.; Swan, Shanna H.

2009-01-01

Plastics have transformed everyday life; usage is increasing and annual production is likely to exceed 300 million tonnes by 2010. In this concluding paper to the Theme Issue on Plastics, the Environment and Human Health, we synthesize current understanding of the benefits and concerns surrounding the use of plastics and look to future priorities, challenges and opportunities. It is evident that plastics bring many societal benefits and offer future technological and medical advances. However, concerns about usage and disposal are diverse and include accumulation of waste in landfills and in natural habitats, physical problems for wildlife resulting from ingestion or entanglement in plastic, the leaching of chemicals from plastic products and the potential for plastics to transfer chemicals to wildlife and humans. However, perhaps the most important overriding concern, which is implicit throughout this volume, is that our current usage is not sustainable. Around 4 per cent of world oil production is used as a feedstock to make plastics and a similar amount is used as energy in the process. Yet over a third of current production is used to make items of packaging, which are then rapidly discarded. Given our declining reserves of fossil fuels, and finite capacity for disposal of waste to landfill, this linear use of hydrocarbons, via packaging and other short-lived applications of plastic, is simply not sustainable. There are solutions, including material reduction, design for end-of-life recyclability, increased recycling capacity, development of bio-based feedstocks, strategies to reduce littering, the application of green chemistry life-cycle analyses and revised risk assessment approaches. Such measures will be most effective through the combined actions of the public, industry, scientists and policymakers. There is some urgency, as the quantity of plastics produced in the first 10 years of the current century is likely to approach the quantity produced in the
Alpha spectrometry without chemistry

International Nuclear Information System (INIS)

Murray, A.S.; Heaton, B.

1983-01-01

A gridded cylindrical pulse ionization chamber is considered for the simultaneous analysis of natural alpha emitters. Solid sources of up to 0.3 g are deposited after wet grinding as a thin layer on 1.1 m 2 of aluminized plastic film, which acts as the cathode. No chemistry is involved, and thus there is little chance of nuclide fractionation. With a ''weightless'' source the resolution is about 55 keV; 110 keV has been easily achieved at 4.2 MeV with real sources. We conclude that significant information about isotope activities in the natural series is available with only a fraction of the work involved in conventional techniques. (author)
Physico-chemical properties of excavated plastic from landfill mining and current recycling routes.

Science.gov (United States)

Canopoli, L; Fidalgo, B; Coulon, F; Wagland, S T

2018-06-01

In Europe over 5.25 billion tonnes of waste has been landfilled between 1995 and 2015. Among this large amount of waste, plastic represents typically 5-25 wt% which is significant and has the potential to be recycled and reintroduced into the circular economy. To date there is still however little information available of the opportunities and challenges in recovering plastics from landfill sites. In this review, the impacts of landfill chemistry on the degradation and/or contamination of excavated plastic waste are analysed. The feasibility of using excavated plastic waste as feedstock for upcycling to valuable chemicals or liquid fuels through thermochemical conversion is also critically discussed. The limited degradation that is experienced by many plastics in landfills (>20 years) which guarantee that large amount is still available is largely due to thermooxidative degradation and the anaerobic conditions. However, excavated plastic waste cannot be conventionally recycled due to high level of ash, impurities and heavy metals. Recent studies demonstrated that pyrolysis offers a cost effective alternative option to conventional recycling. The produced pyrolysis oil is expected to have similar characteristics to petroleum diesel oil. The production of valuable product from excavated plastic waste will also increase the feasibility of enhanced landfill mining projects. However, further studies are needed to investigate the uncertainties about the contamination level and degradation of excavated plastic waste and address their viability for being processed through pyrolysis. Copyright © 2018 Elsevier Ltd. All rights reserved.
Radiation chemistry of plastic crystals. Annual progress report, November 1, 1975--October 31, 1976

International Nuclear Information System (INIS)

Klingen, T.J.

1976-01-01

Results of research on synthesis and plastic crystallinity of adamantane derivatives are presented. Results of electo-optical studies are included along with results of 1-phenyl-o-carborane radiolysis, co-polymerization of o-carborane, and 1-vinyl-o-carborane
Gammastic: towards a pseudo-gamma spectrometry in plastic scintillators

International Nuclear Information System (INIS)

Hamel, Matthieu; Dehe-Pittance, Chrystele; Coulon, Romain; Carrel, Frederick; Pillot, Philippe; Barat, Eric; Dautremer, Thomas; Montagu, Thierry; Normand, Stephane

2013-06-01

War against CBRN-E threats needs to continuously develop sensors with improved detection efficiency. More particularly, this topic concerns the NR controls for homeland security. A first analysis requires indeed a fast gamma spectrometry so as to detect potential special nuclear materials (SNM). To this aim, plastic scintillators could represent the best alternative for the production of large-scale, low-cost radiation portal monitors to be deployed on boarders, tolls, etc. Although they are known to be highly sensitive to gamma rays, due to their poor resolution, information relative to the nature of the SNM is tricky. Thus, only the Compton edge is obtained after interaction, and no information of the photoelectric peak is observed. This project concerns new developments on a possible pseudo-gamma spectrometry performed with plastic scintillators. This project is articulated on a combination of two developments: - The design of new materials most suitable for recovering the photoelectric peak after gamma interaction with the scintillator. This work concerns mainly plastic scintillators loading with heavy elements, such as lead or bismuth. - The analysis of the resulting signal with smart algorithms. This work is thus a pluri-disciplinary work performed at CEA LIST and embeds 4 main disciplines: MCNPX simulations (simulated spectra), chemistry of materials (preparation of various plastic scintillators with different properties), instrumentation (lab experiments) and smart algorithms. Really impressive results were obtained with the unfolding of simulated spectra at various energies (from 241 Am to 60 Co) and an innovative approach was proposed to counter-balance the quenching effect of luminescence by heavy elements in plastic scintillators. (authors)
Catalytic co-pyrolysis of paper biomass and plastic mixtures (HDPE (high density polyethylene), PP (polypropylene) and PET (polyethylene terephthalate)) and product analysis

International Nuclear Information System (INIS)

Chattopadhyay, Jayeeta; Pathak, T.S.; Srivastava, R.; Singh, A.C.

2016-01-01

Catalytic co-pyrolysis of biomass and plastics (HDPE (high density polyethylene), PP (polypropylene) and PET (polyethylene terephthalate)) has been performed in a fixed-bed reactor in presence of cobalt based alumina, ceria and ceria-alumina catalysts to analyze the product distribution and selectivity. Catalysts are synthesized using co-precipitation method and characterized by BET (Brunauer–Emmett–Teller) surface area and XRD analysis. The effect of catalytic co-pyrolysis at different temperature with product distribution has been evaluated. The results have clearly shown the synergistic effect between biomass and plastics, the liquid products gradually increases forming with rise in the plastic content in the blend. Gaseous products have yielded most during pyrolysis of blend having biomass/plastics ratio of 5:1 with the presence of 40% Co/30% CeO_2/30% Al_2O_3 catalyst with hydrogen gas production touched its peak of 47 vol%. Catalytic performance enhanced with increase with the cobalt loading, with best performance attributing to 40% Co/30% CeO_2/30% Al_2O_3 catalyst. - Highlights: • Catalytic co-pyrolysis of biomass and plastics (HDPE, PP & PET) blends in fixed-bed reactor. • Strong synergistic effect evident between biomass and plastics. • Solid residue diminished with application of catalysts. • Aromatics and olefins production increases with higher plastic content. • More hydrogen production with application of catalysts with higher cobalt content.
Highly ordered nanowire arrays on plastic substrates for ultrasensitive flexible chemical sensors.

Science.gov (United States)

McAlpine, Michael C; Ahmad, Habib; Wang, Dunwei; Heath, James R

2007-05-01

The development of a robust method for integrating high-performance semiconductors on flexible plastics could enable exciting avenues in fundamental research and novel applications. One area of vital relevance is chemical and biological sensing, which if implemented on biocompatible substrates, could yield breakthroughs in implantable or wearable monitoring systems. Semiconducting nanowires (and nanotubes) are particularly sensitive chemical sensors because of their high surface-to-volume ratios. Here, we present a scalable and parallel process for transferring hundreds of pre-aligned silicon nanowires onto plastic to yield highly ordered films for low-power sensor chips. The nanowires are excellent field-effect transistors, and, as sensors, exhibit parts-per-billion sensitivity to NO2, a hazardous pollutant. We also use SiO2 surface chemistries to construct a 'nano-electronic nose' library, which can distinguish acetone and hexane vapours via distributed responses. The excellent sensing performance coupled with bendable plastic could open up opportunities in portable, wearable or even implantable sensors.
Highly ordered nanowire arrays on plastic substrates for ultrasensitive flexible chemical sensors

Science.gov (United States)

McAlpine, Michael C.; Ahmad, Habib; Wang, Dunwei; Heath, James R.

2007-05-01

The development of a robust method for integrating high-performance semiconductors on flexible plastics could enable exciting avenues in fundamental research and novel applications. One area of vital relevance is chemical and biological sensing, which if implemented on biocompatible substrates, could yield breakthroughs in implantable or wearable monitoring systems. Semiconducting nanowires (and nanotubes) are particularly sensitive chemical sensors because of their high surface-to-volume ratios. Here, we present a scalable and parallel process for transferring hundreds of pre-aligned silicon nanowires onto plastic to yield highly ordered films for low-power sensor chips. The nanowires are excellent field-effect transistors, and, as sensors, exhibit parts-per-billion sensitivity to NO2, a hazardous pollutant. We also use SiO2 surface chemistries to construct a `nano-electronic nose' library, which can distinguish acetone and hexane vapours via distributed responses. The excellent sensing performance coupled with bendable plastic could open up opportunities in portable, wearable or even implantable sensors.
Methacrylate based cross-linkers for improved thermomechanical properties and retention of radiation detection response in plastic scintillators

Science.gov (United States)

Mahl, Adam; Lim, Allison; Latta, Joseph; Yemam, Henok A.; Greife, Uwe; Sellinger, Alan

2018-03-01

Pulse shape discrimination (PSD) is an important method that can efficiently sort and separate neutron and gamma radiation signals. PSD is currently achieved in plastic scintillators by over-doping poly(vinyl toluene) (PVT) matrices with fluorescent molecules. Meaningful separation of the signals requires addition of >20 wt% 2,5-diphenyloxazole (PPO) fluor in PVT. At these concentrations PPO acts as a plasticizer, negatively affecting the physical properties of the final plastic such as hardness, machinability, and thermomechanical stability. This work addresses these issues by implementing a cost-effective solution using cross-linking chemistry via commercially available bisphenol A dimethacrylate (BPA-DM), and a synthesized fluorinated analogue. Both improve the physical properties of over-doped PPO based plastic scintillators without degrading the measured light yield or PSD and Figure of Merit (FoM). In addition, the fluorinated analogue appears to enhance the hydrophobicity of the surface of the plastic scintillators, which may improve the scintillators' resistance to water diffusion and subsequent radiation response degradation. The new formulations improve the feasibility of widely deploying long lifetime PSD capable plastic scintillators in large area coverage assemblies.
Psychedelics Promote Structural and Functional Neural Plasticity

Directory of Open Access Journals (Sweden)

Calvin Ly

2018-06-01

Full Text Available Summary: Atrophy of neurons in the prefrontal cortex (PFC plays a key role in the pathophysiology of depression and related disorders. The ability to promote both structural and functional plasticity in the PFC has been hypothesized to underlie the fast-acting antidepressant properties of the dissociative anesthetic ketamine. Here, we report that, like ketamine, serotonergic psychedelics are capable of robustly increasing neuritogenesis and/or spinogenesis both in vitro and in vivo. These changes in neuronal structure are accompanied by increased synapse number and function, as measured by fluorescence microscopy and electrophysiology. The structural changes induced by psychedelics appear to result from stimulation of the TrkB, mTOR, and 5-HT2A signaling pathways and could possibly explain the clinical effectiveness of these compounds. Our results underscore the therapeutic potential of psychedelics and, importantly, identify several lead scaffolds for medicinal chemistry efforts focused on developing plasticity-promoting compounds as safe, effective, and fast-acting treatments for depression and related disorders. : Ly et al. demonstrate that psychedelic compounds such as LSD, DMT, and DOI increase dendritic arbor complexity, promote dendritic spine growth, and stimulate synapse formation. These cellular effects are similar to those produced by the fast-acting antidepressant ketamine and highlight the potential of psychedelics for treating depression and related disorders. Keywords: neural plasticity, psychedelic, spinogenesis, synaptogenesis, depression, LSD, DMT, ketamine, noribogaine, MDMA
Psychedelics Promote Structural and Functional Neural Plasticity.

Science.gov (United States)

Ly, Calvin; Greb, Alexandra C; Cameron, Lindsay P; Wong, Jonathan M; Barragan, Eden V; Wilson, Paige C; Burbach, Kyle F; Soltanzadeh Zarandi, Sina; Sood, Alexander; Paddy, Michael R; Duim, Whitney C; Dennis, Megan Y; McAllister, A Kimberley; Ori-McKenney, Kassandra M; Gray, John A; Olson, David E

2018-06-12

Atrophy of neurons in the prefrontal cortex (PFC) plays a key role in the pathophysiology of depression and related disorders. The ability to promote both structural and functional plasticity in the PFC has been hypothesized to underlie the fast-acting antidepressant properties of the dissociative anesthetic ketamine. Here, we report that, like ketamine, serotonergic psychedelics are capable of robustly increasing neuritogenesis and/or spinogenesis both in vitro and in vivo. These changes in neuronal structure are accompanied by increased synapse number and function, as measured by fluorescence microscopy and electrophysiology. The structural changes induced by psychedelics appear to result from stimulation of the TrkB, mTOR, and 5-HT2A signaling pathways and could possibly explain the clinical effectiveness of these compounds. Our results underscore the therapeutic potential of psychedelics and, importantly, identify several lead scaffolds for medicinal chemistry efforts focused on developing plasticity-promoting compounds as safe, effective, and fast-acting treatments for depression and related disorders. Copyright © 2018 The Author(s). Published by Elsevier Inc. All rights reserved.

Crisis Communication (Handbooks of Communication Science Vol. 23)

DEFF Research Database (Denmark)

Johansen, Winni

Vol. 23 - The Handbook of Communication Science General editors: Peter J. Schultz and Paul Cobley......Vol. 23 - The Handbook of Communication Science General editors: Peter J. Schultz and Paul Cobley...
Plasticity theory

CERN Document Server

Lubliner, Jacob

2008-01-01

The aim of Plasticity Theory is to provide a comprehensive introduction to the contemporary state of knowledge in basic plasticity theory and to its applications. It treats several areas not commonly found between the covers of a single book: the physics of plasticity, constitutive theory, dynamic plasticity, large-deformation plasticity, and numerical methods, in addition to a representative survey of problems treated by classical methods, such as elastic-plastic problems, plane plastic flow, and limit analysis; the problem discussed come from areas of interest to mechanical, structural, and
Microbial colonization and degradation of polyethylene and biodegradable plastic bags in temperate fine-grained organic-rich marine sediments.

Science.gov (United States)

Nauendorf, Alice; Krause, Stefan; Bigalke, Nikolaus K; Gorb, Elena V; Gorb, Stanislav N; Haeckel, Matthias; Wahl, Martin; Treude, Tina

2016-02-15

To date, the longevity of plastic litter at the sea floor is poorly constrained. The present study compares colonization and biodegradation of plastic bags by aerobic and anaerobic benthic microbes in temperate fine-grained organic-rich marine sediments. Samples of polyethylene and biodegradable plastic carrier bags were incubated in natural oxic and anoxic sediments from Eckernförde Bay (Western Baltic Sea) for 98 days. Analyses included (1) microbial colonization rates on the bags, (2) examination of the surface structure, wettability, and chemistry, and (3) mass loss of the samples during incubation. On average, biodegradable plastic bags were colonized five times higher by aerobic and eight times higher by anaerobic microbes than polyethylene bags. Both types of bags showed no sign of biodegradation during this study. Therefore, marine sediment in temperate coastal zones may represent a long-term sink for plastic litter and also supposedly compostable material. Copyright © 2016 Elsevier Ltd. All rights reserved.
Regioregular narrow-bandgap-conjugated polymers for plastic electronics

Science.gov (United States)

Ying, Lei; Huang, Fei; Bazan, Guillermo C.

2017-03-01

Progress in the molecular design and processing protocols of semiconducting polymers has opened significant opportunities for the fabrication of low-cost plastic electronic devices. Recent studies indicate that field-effect transistors and organic solar cells fabricated using narrow-bandgap regioregular polymers with translational symmetries in the direction of the backbone vector often outperform those containing analogous regiorandom polymers. This review addresses the cutting edge of regioregularity chemistry, in particular how to control the spatial distribution in the molecular structures and how this order translates to more ordered bulk morphologies. The effect of regioregularity on charge transport and photovoltaic properties is also outlined.
Structure vs chemistry: friction and wear of Pt-based metallic surfaces.

Science.gov (United States)

Caron, A; Louzguine-Luzguin, D V; Bennewitz, R

2013-11-13

In comparison of a Pt57.5Cu14.7Ni5.3P22.5 metallic glass with a Pt(111) single crystal we find that wearless friction is determined by chemistry through bond formation alloying, while wear is determined by structure through plasticity mechanisms. In the wearless regime, friction is affected by the chemical composition of the counter body and involves the formation of a liquid-like neck and interfacial alloying. The wear behavior of Pt-based metallic surfaces is determined by their structural properties and corresponding mechanisms for plastic deformation. In the case of Pt(111) wear occurs by dislocation-mediated homogeneous plastic deformation. In contrast the wear of Pt57.5Cu14.7Ni5.3P22.5 metallic glass occurs through localized plastic deformation in shear bands that merge together in a single shear zone above a critical load and corresponds to the shear softening of metallic glasses. These results open a new route in the control of friction and wear of metals and are relevant for the development of self-lubricated and wear-resistant mechanical devices.
Structural Chemistry of Human RNA Methyltransferases.

Science.gov (United States)

Schapira, Matthieu

2016-03-18

RNA methyltransferases (RNMTs) play important roles in RNA stability, splicing, and epigenetic mechanisms. They constitute a promising target class that is underexplored by the medicinal chemistry community. Information of relevance to drug design can be extracted from the rich structural coverage of human RNMTs. In this work, the structural chemistry of this protein family is analyzed in depth. Unlike most methyltransferases, RNMTs generally feature a substrate-binding site that is largely open on the cofactor-binding pocket, favoring the design of bisubstrate inhibitors. Substrate purine or pyrimidines are often sandwiched between hydrophobic walls that can accommodate planar ring systems. When the substrate base is laying on a shallow surface, a 5' flanking base is sometimes anchored in a druggable cavity. The cofactor-binding site is structurally more diverse than in protein methyltransferases and more druggable in SPOUT than in Rossman-fold enzymes. Finally, conformational plasticity observed both at the substrate and cofactor binding sites may be a challenge for structure-based drug design. The landscape drawn here may inform ongoing efforts toward the discovery of the first human RNMT inhibitors.
Magical Engineering Plastic

Energy Technology Data Exchange (ETDEWEB)

Kim, Gwang Ung

1988-01-15

This book introduces engineering plastic about advantage of engineering plastic, plastic material from processing method, plastic shock, plastic until now, background of making of engineering plastic, wonderful engineering plastic science such as a high molecule and molecule, classification of high molecule, difference between metal and high molecule, heat and high molecule materials, and property of surface, engineering plastic of dream like from linseed oil to aramid, small dictionary of engineering plastic.
Magical Engineering Plastic

International Nuclear Information System (INIS)

Kim, Gwang Ung

1988-01-01

This book introduces engineering plastic about advantage of engineering plastic, plastic material from processing method, plastic shock, plastic until now, background of making of engineering plastic, wonderful engineering plastic science such as a high molecule and molecule, classification of high molecule, difference between metal and high molecule, heat and high molecule materials, and property of surface, engineering plastic of dream like from linseed oil to aramid, small dictionary of engineering plastic.
International policies to reduce plastic marine pollution from single-use plastics (plastic bags and microbeads): A review.

Science.gov (United States)

Xanthos, Dirk; Walker, Tony R

2017-05-15

Marine plastic pollution has been a growing concern for decades. Single-use plastics (plastic bags and microbeads) are a significant source of this pollution. Although research outlining environmental, social, and economic impacts of marine plastic pollution is growing, few studies have examined policy and legislative tools to reduce plastic pollution, particularly single-use plastics (plastic bags and microbeads). This paper reviews current international market-based strategies and policies to reduce plastic bags and microbeads. While policies to reduce microbeads began in 2014, interventions for plastic bags began much earlier in 1991. However, few studies have documented or measured the effectiveness of these reduction strategies. Recommendations to further reduce single-use plastic marine pollution include: (i) research to evaluate effectiveness of bans and levies to ensure policies are having positive impacts on marine environments; and (ii) education and outreach to reduce consumption of plastic bags and microbeads at source. Copyright © 2017 Elsevier Ltd. All rights reserved.
Towards long lasting zirconia-based composites for dental implants: Transformation induced plasticity and its consequence on ceramic reliability.

Science.gov (United States)

Reveron, Helen; Fornabaio, Marta; Palmero, Paola; Fürderer, Tobias; Adolfsson, Erik; Lughi, Vanni; Bonifacio, Alois; Sergo, Valter; Montanaro, Laura; Chevalier, Jérôme

2017-01-15

Zirconia-based composites were developed through an innovative processing route able to tune compositional and microstructural features very precisely. Fully-dense ceria-stabilized zirconia ceramics (84vol% Ce-TZP) containing equiaxed alumina (8vol%Al 2 O 3 ) and elongated strontium hexa-aluminate (8vol% SrAl 12 O 19 ) second phases were obtained by conventional sintering. This work deals with the effect of the zirconia stabilization degree (CeO 2 in the range 10.0-11.5mol%) on the transformability and mechanical properties of Ce-TZP-Al 2 O 3 -SrAl 12 O 19 materials. Vickers hardness, biaxial flexural strength and Single-edge V-notched beam tests revealed a strong influence of ceria content on the mechanical properties. Composites with 11.0mol% CeO 2 or above exhibited the classical behaviour of brittle ceramics, with no apparent plasticity and very low strain to failure. On the contrary, composites with 10.5mol% CeO 2 or less showed large transformation-induced plasticity and almost no dispersion in strength data. Materials with 10.5mol% of ceria showed the highest values in terms of biaxial bending strength (up to 1.1GPa) and fracture toughness (>10MPa√m). In these ceramics, as zirconia transformation precedes failure, the Weibull modulus was exceptionally high and reached a value of 60, which is in the range typically reported for metals. The results achieved demonstrate the high potential of using these new strong, tough and stable zirconia-based composites in structural biomedical applications. Yttria-stabilized (Y-TZP) zirconia ceramics are increasingly used for developing metal-free restorations and dental implants. Despite their success related to their excellent mechanical resistance, Y-TZP can undergo Low Temperature Degradation which could be responsible for restoration damage or even worst the failure of the implant. Current research is focusing on strategies to improve the LTD resistance of Y-TZP or to develop alternative composites with better
Characterization of the surface physico-chemistry of plasticized PVC used in blood bag and infusion tubing.

Science.gov (United States)

Al Salloum, H; Saunier, J; Dazzi, A; Vigneron, J; Etcheberry, A; Marlière, C; Aymes-Chodur, C; Herry, J M; Bernard, M; Jubeli, E; Yagoubi, N

2017-06-01

Commercial infusion tubing and blood storage devices (tubing, blood and platelets bags) made of plasticized PVC were analyzed by spectroscopic, chromatographic and microscopic techniques in order to identify and quantify the additives added to the polymer (lubricants, thermal stabilizers, plasticizers) and to put into evidence their blooming onto the surface of the devices. For all the samples, deposits were observed on the surface but with different kinds of morphologies. Ethylene bis amide lubricant and metallic stearate stabilizers were implicated in the formation of these layers. In contact with aqueous media, these insoluble deposits were damaged, suggesting a possible particulate contamination of the infused solutions. Copyright © 2017 Elsevier B.V. All rights reserved.
Analytical method for predicting plastic flow in notched fiber composite materials

International Nuclear Information System (INIS)

Flynn, P.L.; Ebert, L.J.

1977-01-01

An analytical system was developed for prediction of the onset and progress of plastic flow of oriented fiber composite materials in which both externally applied complex stress states and stress raisers were present. The predictive system was a unique combination of two numerical systems, the ''SAAS II'' finite element analysis system and a micromechanics finite element program. The SAAS II system was used to generate the three-dimensional stress distributions, which were used as the input into the finite element micromechanics program. Appropriate yielding criteria were then applied to this latter program. The accuracy of the analytical system was demonstrated by the agreement between the analytically predicted and the experimentally measured flow values of externally notched tungsten wire reinforced copper oriented fiber composites, in which the fiber fraction was 50 vol pct
Advances in boundary elements. Vol. 1-3

International Nuclear Information System (INIS)

Brebbia, C.A.; Connor, J.J.

1989-01-01

This book contains some of the edited papers presented at the 11th Boundary Element Conference, held in Cambridge, Massachusetts, during August 1989. The papers are arranged in three different books comprising the following topics: Vol. 1: Computations and Fundamentals - comprises sections on fundamentals, adaptive techniques, error and convergence, numerical methods and computational aspects. (283 p.). Vol. 2: Field and fluid flow solutions - includes the following topics: potential problems, thermal studies, electrical and electromagnetic problems, wave propagation, acoustics and fluid flow. (484 p.). Vol. 3: Stress analysis - deals with advances in linear problems, nonlinear problems, fracture mechanics, contact mechanics, optimization, geomechanics, plates and shells, vibrations and industrial applications. (450 p). (orig./HP)
The world made by Noble prize : chemistry volume I

International Nuclear Information System (INIS)

2007-06-01

This book contains two parts about items by chemistry. The first part introduces Alfred Bernhard Nodel, Pioneers without Nobel Prize, Garbage Bag, Non-sticky Frying Pan, Nylon Stockings, Plastic Electricity, Synthetic Dyestuff, Gin and Tonic, Soccer Ball, Fertilizer, DDT, Dentifrice, Kimchi, Makgeolli, Ice cream, Anodyne and Firefly. The second part lists PET-MRI, Color photo, Holography, Art diamond Incandescent lamp and Neon Sign, Imitation work, Alchemy, Nuclear Power plant, Synthetic Oil and Sugar, Freon gas, Water Car, Estate agency Mars, and winners of Nobel prize in physics.
The world made by Noble prize : chemistry volume I

Energy Technology Data Exchange (ETDEWEB)

NONE

2007-06-15

This book contains two parts about items by chemistry. The first part introduces Alfred Bernhard Nodel, Pioneers without Nobel Prize, Garbage Bag, Non-sticky Frying Pan, Nylon Stockings, Plastic Electricity, Synthetic Dyestuff, Gin and Tonic, Soccer Ball, Fertilizer, DDT, Dentifrice, Kimchi, Makgeolli, Ice cream, Anodyne and Firefly. The second part lists PET-MRI, Color photo, Holography, Art diamond Incandescent lamp and Neon Sign, Imitation work, Alchemy, Nuclear Power plant, Synthetic Oil and Sugar, Freon gas, Water Car, Estate agency Mars, and winners of Nobel prize in physics.
Development of Process for Disposal of Plastic Waste Using Plasma Pyrolysis Technology and Option for Energy Recovery

Czech Academy of Sciences Publication Activity Database

Punčochář, Miroslav; Ruj, B.; Chatterj, P.K.

2012-01-01

Roč. 42, SI (2012), s. 420-430 E-ISSN 1877-7058. [International Congress of Chemical and Process Engineering CHISA 2012 and 15th Conference PRES 2012 /20./. Prague, 25.08.2012-29.08.2012] Institutional support: RVO:67985858 Keywords : plastic waste * plasma pyrolysis * syngas Subject RIV: CI - Industrial Chemistry, Chemical Engineering
Continuing Medical Education - Vol 27, No 1 (2009)

African Journals Online (AJOL)

Continuing Medical Education - Vol 27, No 1 (2009). Journal Home > Archives > Vol 27, No 1 (2009). Log in or Register to get access to full text downloads. ... Addiction treatment · EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT. R Meyer ...
BIODEGRADABLE PLASTICS FROM A MIXTURE OF LOW DENSITY POLYETHYLENE (LDPE AND CASSAVA STARCH WITH THE ADDITION OF ACRYLIC ACID

Directory of Open Access Journals (Sweden)

Susilawati Susilawati

2013-05-01

Full Text Available A research of preparation biodegradable plastics, from LDPE and cassava starch mixture with the addition of acrylic acid, had been conducted. This research purpose to studied compatibility properties of the material and percent weight loss during the biodegradation test. Optimum weight loss (59,26% was showed after 60 days witches LDPE and starch composition ratio 6 : 4 (w/w while tensile strength equal to 0,38 Kgf/mm2. SEM characterization showed that biodegradation has occurred by formation of hole in the biodegradable plastic surface. DTA test gave Tg = 130 °C, Tm = 230 °C and Td = 370-450 °C while FT-IR analysis showed that the biodegradable plastics have a chemistry interaction.
The world made by Noble prize : chemistry volume II

International Nuclear Information System (INIS)

2007-06-01

This book has two parts of items related chemistry. The contents of the first part are Preface, Alfred Bemhard Nobel, Pioneers without Nobel Prize, Garbage Bag, Non-sticky Frying Pan, Nylon Stockings, Plastic Electricity, Synthetic Dyestuff, Gin and Tonic, Soccer Ball, Fertilizer, DDT, Dentifrice, Kimchi, Makgeolli, Ice cream, Anodyne, and firefly. The contents of the second part are PET-MRI, Color photo, Holography, Art diamond, an incandescent lamp and Neon Sign, Imitation works, Alchemy, Nuclear Power plant, Synthetic Oil and Sugar, Propane gas, Water Car, Estate agency Mars, and reference.
The world made by Noble prize : chemistry volume II

Energy Technology Data Exchange (ETDEWEB)

NONE

2007-06-15

This book has two parts of items related chemistry. The contents of the first part are Preface, Alfred Bemhard Nobel, Pioneers without Nobel Prize, Garbage Bag, Non-sticky Frying Pan, Nylon Stockings, Plastic Electricity, Synthetic Dyestuff, Gin and Tonic, Soccer Ball, Fertilizer, DDT, Dentifrice, Kimchi, Makgeolli, Ice cream, Anodyne, and firefly. The contents of the second part are PET-MRI, Color photo, Holography, Art diamond, an incandescent lamp and Neon Sign, Imitation works, Alchemy, Nuclear Power plant, Synthetic Oil and Sugar, Propane gas, Water Car, Estate agency Mars, and reference.

International Journal of Humanistic Studies - Vol 3 (2004)

African Journals Online (AJOL)

International Journal of Humanistic Studies - Vol 3 (2004). Journal Home > Archives > Vol 3 (2004). Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives. DOWNLOAD FULL TEXT ...
Evaluation of Capacity on a High Throughput Vol-oxidizer for Operability

International Nuclear Information System (INIS)

Kim, Young Hwan; Park, Geun Il; Lee, Jung Won; Jung, Jae Hoo; Kim, Ki Ho; Lee, Yong Soon; Lee, Do Youn; Kim, Su Sung

2010-01-01

KAERI is developing a pyro-process. As a piece of process equipment, a high throughput vol-oxidizer which can handle a several tens kg HM/batch was developed to supply U 3 O 8 powders to an electrolytic reduction(ER) reactor. To increase the reduction yield, UO 2 pellets should be converted into uniform powders. In this paper, we aim at the evaluation of a high throughput vol-oxidizer for operability. The evaluation consisted of 3 targets, a mechanical motion test, a heating test and hull separation test. In order to test a high throughput vol-oxidizer, By using a control system, mechanical motion tests of the vol-oxidizer were conducted, and heating rates were analyzed. Also the separation tests of hulls for recovery rate were conducted. The test results of the vol-oxidizer are going to be applied for operability. A study on the characteristics of the volatile gas produced during a vol-oxidation process is not included in this study
Student Scientific Conference, 2008. Collection of contributions. Vol. 2 - Sections of geography, geology, environment, chemistry and didactics

International Nuclear Information System (INIS)

2008-04-01

The conference included the following sections: (i) Biology (114 contributions); (ii) Geography (37 contributions); (iii) Geology (24 contributions); (iv) Environment (16 contributions); (v) Chemistry (11 contributions); (vi) Didactics (8 contributions). Contributions relevant to INIS interest have been inputted to INIS.
Dynamics of structures '89. Vol. 3

International Nuclear Information System (INIS)

1989-01-01

The proceedings, comprising 3 volumes published by the Plzen Centre of the Czechoslovak Society for Science and Technology (Vol. 1 and 2) and by Skoda Works in Plzen (Vol. 3), contain 107 papers, out of which 8 fall within the INIS Subject Scope; these deal with problems related to the earthquake resistance of nuclear power plants. Attention is paid to the evaluation of seismic characteristics of nuclear power plant equipment, to the equipment testing and to calculations of its dynamic characteristics under simulated seismic stress. (Z.M.)
Plastic Surgery

Science.gov (United States)

... Staying Safe Videos for Educators Search English Español Plastic Surgery KidsHealth / For Teens / Plastic Surgery What's in ... her forehead lightened with a laser? What Is Plastic Surgery? Just because the name includes the word " ...
Plastic dosimeter

International Nuclear Information System (INIS)

Nagai, Shiro; Matsuda, Kohji.

1988-01-01

The report outlines major features and applications of plastic dosimeters. Some plastic dosimeters, including the CTA and PVC types, detect the response of the plastic material itself to radiations while others, such as pigment-added plastic dosimeters, contain additives as radiation detecting material. Most of these dosimeters make use of color centers produced in the dosimeter by radiations. The PMMA dosimeter is widely used in the field of radiation sterilization of food, feed and medical apparatus. The blue cellophane dosimeter is easy to handle if calibrated appropriately. The rad-color dosimeter serves to determine whether products have been irradiated appropriately. The CTA dosimeter has better damp proofing properties than the blue cellophane type. The pigment-added plastic dosimeter consists of a resin such as nylon, CTA or PVC that contains a dye. Some other plastic dosimeters are also described briefly. Though having many advantages, these plastic dosimeter have disadvantages as well. Some of their major disadvantages, including fading as well as large dependence on dose, temperature, humidity and anviroment, are discussed. (Nogami, K.)
Delivery, Effect on Cell Viability, and Plasticity of Modified Aptamer Constructs

DEFF Research Database (Denmark)

Gissberg, Olof; Zaghloul, Eman M; Lundin, Karin E

2016-01-01

AS1411 is a g-quadruplex-forming aptamer capable of selectively entering cancer cells by nucleolin receptor-mediated uptake. In this study, we investigated the cell internalization properties and plasticity of AS1411 carrying different locked nucleic acid-containing cargo oligonucleotides (ONs......) for delivery into A549 and U2OS cells. We found that internalization efficiency is highly governed by ON cargo chemistry and composition since the inherent antitumor properties of AS1411 were lost when attached to a nontoxic ON, noTox. However, a toxic ON, Tox, demonstrated potent cytotoxicity after aptamer...
New developments in ophthalmic coatings on plastic lenses

Science.gov (United States)

Eigenmann, H. P.; Lobsiger, W.; Suter, R.

1998-02-01

The origin of vision aids such as eyeglasses, magnifying glasses, telescopes and so forth lies in the distant past and cannot be dated with precision. However, such aids certainly came into use at different times in different cultures. Early portraits and other pictures prove to a certainty, however, that remarkable well-made spectacles were in use by the end of the Middle Ages. Glass was employed for optical lenses from the very beginning, and quality improved continuously with advances in glassmaking and polishing techniques. Starting around 1970, this continuing development received new impetus from the introduction of plastics as a new material for ophthalmic lenses. Rapid progress in plastics chemistry had epoch-making effects on lens technology, and today a wide variety of materials such as CR39, PMMA and polycarbonates, with refractive indices ranging from 1.52 to 1.65, are used for this purpose. Eyeglasses have long been important on other grounds than vision correction; people wear them as adornment, because they are fashionable, to express their personality, and for other reasons. This dramatic history shows no signs of coming to an end, and more innovations are definitely ahead.
plastic waste recycling

African Journals Online (AJOL)

Dr Ahmed

incinerators is increasing around the world. Discarded plastic products ... Agency (EPA) estimated that the amount of plastics throw away is. 50 % greater in the ... The waste plastics were identified using the Society of the Plastic. Industry (SPI) ...
Third Chemistry Conference on Recent Trends in Chemistry

International Nuclear Information System (INIS)

Saeed, M.M.; Wheed, S.

2011-01-01

The third chemistry conference 2011 on recent trends in chemistry was held from October 17-19, 2001 at Islamabad, Pakistan. More than 65 papers and oral presentation. The scope of the conference was wide open and provides and opportunity for participation of broad spectrum of chemists. This forum provided a platform for the dissemination of the latest research followed by discussion pertaining to new trends in chemistry. This con fence covered different aspects of subjects including analytical chemistry, environmental chemistry, polymer chemistry, industrial chemistry, biochemistry and nano chemistry etc. (A.B.)
Cell plasticity and heterogeneity in cancer.

Science.gov (United States)

Marjanovic, Nemanja D; Weinberg, Robert A; Chaffer, Christine L

2013-01-01

Heterogeneity within a given cancer arises from diverse cell types recruited to the tumor and from genetic and/or epigenetic differences amongst the cancer cells themselves. These factors conspire to create a disease with various phenotypes. There are 2 established models of cancer development and progression to metastatic disease. These are the clonal evolution and cancer stem cell models. The clonal evolution theory suggests that successive mutations accumulating in a given cell generate clonal outgrowths that thrive in response to microenvironmental selection pressures, dictating the phenotype of the tumor. The alternative cancer stem cell (CSC) model suggests that cancer cells with similar genetic backgrounds can be hierarchically organized according to their tumorigenic potential. Accordingly, CSCs reside at the apex of the hierarchy and are thought to possess the majority of a cancer's tumor-initiating and metastatic ability. A defining feature of this model is its apparent unidirectional nature, whereby CSCs undergo symmetric division to replenish the CSC pool and irreversible asymmetric division to generate daughter cells (non-CSCs) with low tumorigenic potential. However, evolving evidence supports a new model of tumorigenicity, in which considerable plasticity exists between the non-CSC and CSC compartments, such that non-CSCs can reacquire a CSC phenotype. These findings suggest that some tumors may adhere to a plastic CSC model, in which bidirectional conversions are common and essential components of tumorigenicity. Accumulating evidence surrounding the plasticity of cancer cells, in particular, suggests that aggressive CSCs can be created de novo within a tumor. Given the current focus on therapeutic targeting of CSCs, we discuss the implications of non-CSC-to-CSC conversions on the development of future therapies. © 2012 American Association for Clinical Chemistry
Direct liquefaction of plastics and coprocessing of coal with plastics

Energy Technology Data Exchange (ETDEWEB)

Huffman, G.P.; Feng, Z.; Mahajan, V. [Univ. of Kentucky, Lexington, KY (United States)

1995-12-31

The objectives of this work were to optimize reaction conditions for the direct liquefaction of waste plastics and the coprocessing of coal with waste plastics. In previous work, the direct liquefaction of medium and high density polyethylene (PE), polypropylene (PPE), poly(ethylene terephthalate) (PET), and a mixed plastic waste, and the coliquefaction of these plastics with coals of three different ranks was studied. The results established that a solid acid catalyst (HZSM-5 zeolite) was highly active for the liquefaction of the plastics alone, typically giving oil yields of 80-95% and total conversions of 90-100% at temperatures of 430-450 {degrees}C. In the coliquefaction experiments, 50:50 mixtures of plastic and coal were used with a tetralin solvent (tetralin:solid = 3:2). Using approximately 1% of the HZSM-5 catalyst and a nanoscale iron catalyst, oil yields of 50-70% and total conversion of 80-90% were typical. In the current year, further investigations were conducted of the liquefaction of PE, PPE, and a commingled waste plastic obtained from the American Plastics Council (APC), and the coprocessing of PE, PPE and the APC plastic with Black Thunder subbituminous coal. Several different catalysts were used in these studies.
Vol 41 No 2

African Journals Online (AJOL)

Esem

3 Centre for Primary Care Research. Medical Journal of Zambia, Vol. 41, No. 2: 59 - 64 (2014) ... pollutants by inhaling second-hand tobacco smoke are at risk of adverse health ..... To put the measured PM levels into perspective, a. 2.5. 5.
Constitutional dynamic chemistry: bridge from supramolecular chemistry to adaptive chemistry.

Science.gov (United States)

Lehn, Jean-Marie

2012-01-01

Supramolecular chemistry aims at implementing highly complex chemical systems from molecular components held together by non-covalent intermolecular forces and effecting molecular recognition, catalysis and transport processes. A further step consists in the investigation of chemical systems undergoing self-organization, i.e. systems capable of spontaneously generating well-defined functional supramolecular architectures by self-assembly from their components, thus behaving as programmed chemical systems. Supramolecular chemistry is intrinsically a dynamic chemistry in view of the lability of the interactions connecting the molecular components of a supramolecular entity and the resulting ability of supramolecular species to exchange their constituents. The same holds for molecular chemistry when the molecular entity contains covalent bonds that may form and break reversibility, so as to allow a continuous change in constitution by reorganization and exchange of building blocks. These features define a Constitutional Dynamic Chemistry (CDC) on both the molecular and supramolecular levels.CDC introduces a paradigm shift with respect to constitutionally static chemistry. The latter relies on design for the generation of a target entity, whereas CDC takes advantage of dynamic diversity to allow variation and selection. The implementation of selection in chemistry introduces a fundamental change in outlook. Whereas self-organization by design strives to achieve full control over the output molecular or supramolecular entity by explicit programming, self-organization with selection operates on dynamic constitutional diversity in response to either internal or external factors to achieve adaptation.The merging of the features: -information and programmability, -dynamics and reversibility, -constitution and structural diversity, points to the emergence of adaptive and evolutive chemistry, towards a chemistry of complex matter.
Experimental design in chemistry: A tutorial.

Science.gov (United States)

Leardi, Riccardo

2009-10-12

In this tutorial the main concepts and applications of experimental design in chemistry will be explained. Unfortunately, nowadays experimental design is not as known and applied as it should be, and many papers can be found in which the "optimization" of a procedure is performed one variable at a time. Goal of this paper is to show the real advantages in terms of reduced experimental effort and of increased quality of information that can be obtained if this approach is followed. To do that, three real examples will be shown. Rather than on the mathematical aspects, this paper will focus on the mental attitude required by experimental design. The readers being interested to deepen their knowledge of the mathematical and algorithmical part can find very good books and tutorials in the references [G.E.P. Box, W.G. Hunter, J.S. Hunter, Statistics for Experimenters: An Introduction to Design, Data Analysis, and Model Building, John Wiley & Sons, New York, 1978; R. Brereton, Chemometrics: Data Analysis for the Laboratory and Chemical Plant, John Wiley & Sons, New York, 1978; R. Carlson, J.E. Carlson, Design and Optimization in Organic Synthesis: Second Revised and Enlarged Edition, in: Data Handling in Science and Technology, vol. 24, Elsevier, Amsterdam, 2005; J.A. Cornell, Experiments with Mixtures: Designs, Models and the Analysis of Mixture Data, in: Series in Probability and Statistics, John Wiley & Sons, New York, 1991; R.E. Bruns, I.S. Scarminio, B. de Barros Neto, Statistical Design-Chemometrics, in: Data Handling in Science and Technology, vol. 25, Elsevier, Amsterdam, 2006; D.C. Montgomery, Design and Analysis of Experiments, 7th edition, John Wiley & Sons, Inc., 2009; T. Lundstedt, E. Seifert, L. Abramo, B. Thelin, A. Nyström, J. Pettersen, R. Bergman, Chemolab 42 (1998) 3; Y. Vander Heyden, LC-GC Europe 19 (9) (2006) 469].
Recycling of Plastic

DEFF Research Database (Denmark)

Christensen, Thomas Højlund; Fruergaard, Thilde

2011-01-01

Plastic is produced from fossil oil. Plastic is used for many different products. Some plastic products like, for example, wrapping foil, bags and disposable containers for food and beverage have very short lifetimes and thus constitute a major fraction of most waste. Other plastic products like...
Radiation chemistry

International Nuclear Information System (INIS)

Rodgers, F.; Rodgers, M.A.

1987-01-01

The contents of this book include: Interaction of ionizing radiation with matter; Primary products in radiation chemistry; Theoretical aspects of radiation chemistry; Theories of the solvated electron; The radiation chemistry of gases; Radiation chemistry of colloidal aggregates; Radiation chemistry of the alkali halides; Radiation chemistry of polymers; Radiation chemistry of biopolymers; Radiation processing and sterilization; and Compound index
Semantic modeling of plastic deformation of polycrystalline rock

Science.gov (United States)

Babaie, Hassan A.; Davarpanah, Armita

2018-02-01

We have developed the first iteration of the Plastic Rock Deformation (PRD) ontology by modeling the semantics of a selected set of deformational processes and mechanisms that produce, reconfigure, displace, and/or consume the material components of inhomogeneous polycrystalline rocks. The PRD knowledge model also classifies and formalizes the properties (relations) that hold between instances of the dynamic physical and chemical processes and the rock components, the complex physio-chemical, mathematical, and informational concepts of the plastic rock deformation system, the measured or calculated laboratory testing conditions, experimental procedures and protocols, the state and system variables, and the empirical flow laws that define the inter-relationships among the variables. The ontology reuses classes and properties from several existing ontologies that are built for physics, chemistry, biology, and mathematics. With its flexible design, the PRD ontology is well positioned to incrementally develop into a model that more fully represents the knowledge of plastic deformation of polycrystalline rocks in the future. The domain ontology will be used to consistently annotate varied data and information related to the microstructures and the physical and chemical processes that produce them at different spatial and temporal scales in the laboratory and in the solid Earth. The PRDKB knowledge base, when built based on the ontology, will help the community of experimental structural geologists and metamorphic petrologists to coherently and uniformly distribute, discover, access, share, and use their data through automated reasoning and integration and query of heterogeneous experimental deformation data that originate from autonomous rock testing laboratories.
Index to Nuclear Safety. A technical progress review by chronology, permuted title, and author. Vol. 11, No. 1 through Vol. 15, No. 6

International Nuclear Information System (INIS)

Cottrell, W.B.; Klein, A.

1975-04-01

This issue of the Index to Nuclear Safety covers only articles included in Nuclear Safety, Vol. 11, No. 1, through Vol. 15, No. 6. This index is presented in three sections as follows: Chronological List of Articles by Volume; Permuted Title (KWIC) Index; and Author Index. (U.S.)
Economic and Policy Review - Vol 13, No 3 (2007)

African Journals Online (AJOL)

Economic and Policy Review - Vol 13, No 3 (2007). Journal Home > Archives > Vol 13, No 3 ... Snagging the wheel of progress: Corruption, New anti-corruption drive and Nigeria\\'s quest for development. S B Kura ... Book Review: challenges of African growth opportunities, constraints and strategic directions. S I Owualah ...

Theoretical chemistry periodicities in chemistry and biology

CERN Document Server

Eyring, Henry

1978-01-01

Theoretical Chemistry: Periodicities in Chemistry and Biology, Volume 4 covers the aspects of theoretical chemistry. The book discusses the stably rotating patterns of reaction and diffusion; the chemistry of inorganic systems exhibiting nonmonotonic behavior; and population cycles. The text also describes the mathematical modeling of excitable media in neurobiology and chemistry; oscillating enzyme reactions; and oscillatory properties and excitability of the heart cell membrane. Selected topics from the theory of physico-chemical instabilities are also encompassed. Chemists, mechanical engin
Zede Journal - Vol 29 (2012)

African Journals Online (AJOL)

Journal Home > Archives > Vol 29 (2012) ... Leakage aware hardware and stochastic power scheduling for smart mobile devices ... Energy efficient topology for Wireless Mesh Networks · EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT
Progress in coating and radiation curing of metal and plastic objects

International Nuclear Information System (INIS)

Mayenknecht, H.

1983-01-01

The manyfold problems with one or multi-layered coatings on metal and plastic surfaces as adhesion and coat compound are the reasons for a rather slow progress of industrial applications of both radiation curing technologies (UV and EBC). Important reasons for this seemed to result from the fact that the manyfold offers of radiation sources were not optimum adapted to the chemistry of the coating materials. It was pointed out that tensions due to film contraction during polymerization process are the main reasons for insufficient adhesion. This presentation is an attempt to clarify both points of view
Plastic value chains

DEFF Research Database (Denmark)

Baxter, John; Wahlstrom, Margareta; Zu Castell-Rüdenhausen, Malin

2014-01-01

Optimizing plastic value chains is regarded as an important measure in order to increase recycling of plastics in an efficient way. This can also lead to improved awareness of the hazardous substances contained in plastic waste, and how to avoid that these substances are recycled. As an example......, plastics from WEEE is chosen as a Nordic case study. The project aims to propose a number of improvements for this value chain together with representatives from Nordic stakeholders. Based on the experiences made, a guide for other plastic value chains shall be developed....
Our plastic age.

Science.gov (United States)

Thompson, Richard C; Swan, Shanna H; Moore, Charles J; vom Saal, Frederick S

2009-07-27

Within the last few decades, plastics have revolutionized our daily lives. Globally we use in excess of 260 million tonnes of plastic per annum, accounting for approximately 8 per cent of world oil production. In this Theme Issue of Philosophical Transactions of the Royal Society, we describe current and future trends in usage, together with the many benefits that plastics bring to society. At the same time, we examine the environmental consequences resulting from the accumulation of waste plastic, the effects of plastic debris on wildlife and concerns for human health that arise from the production, usage and disposal of plastics. Finally, we consider some possible solutions to these problems together with the research and policy priorities necessary for their implementation.
Our plastic age

Science.gov (United States)

Thompson, Richard C.; Swan, Shanna H.; Moore, Charles J.; vom Saal, Frederick S.

2009-01-01

Within the last few decades, plastics have revolutionized our daily lives. Globally we use in excess of 260 million tonnes of plastic per annum, accounting for approximately 8 per cent of world oil production. In this Theme Issue of Philosophical Transactions of the Royal Society, we describe current and future trends in usage, together with the many benefits that plastics bring to society. At the same time, we examine the environmental consequences resulting from the accumulation of waste plastic, the effects of plastic debris on wildlife and concerns for human health that arise from the production, usage and disposal of plastics. Finally, we consider some possible solutions to these problems together with the research and policy priorities necessary for their implementation. PMID:19528049
Complex chemistry

International Nuclear Information System (INIS)

Kim, Bong Gon; Kim, Jae Sang; Kim, Jin Eun; Lee, Boo Yeon

2006-06-01

This book introduces complex chemistry with ten chapters, which include development of complex chemistry on history coordination theory and Warner's coordination theory and new development of complex chemistry, nomenclature on complex with conception and define, chemical formula on coordination compound, symbol of stereochemistry, stereo structure and isomerism, electron structure and bond theory on complex, structure of complex like NMR and XAFS, balance and reaction on solution, an organo-metallic chemistry, biology inorganic chemistry, material chemistry of complex, design of complex and calculation chemistry.
Impact of Bio-Based Plastics on Current Recycling of Plastics

Directory of Open Access Journals (Sweden)

Luc Alaerts

2018-05-01

Full Text Available Bio-based plastics are increasingly appearing in a range of consumption products, and after use they often end up in technical recycling chains. Bio-based plastics are different from fossil-based ones and could disturb the current recycling of plastics and hence inhibit the closure of plastic cycles, which is undesirable given the current focus on a transition towards a circular economy. In this paper, this risk has been assessed via three elaborated case studies using data and information retrieved through an extended literature search. No overall risks were revealed for bio-based plastics as a group; rather, every bio-based plastic is to be considered as a potential separate source of contamination in current recycling practices. For PLA (polylactic acid, a severe incompatibility with PET (polyethylene terephthalate recycling is known; hence, future risks are assessed by measuring amounts of PLA ending up in PET waste streams. For PHA (polyhydroxy alkanoate there is no risk currently, but it will be crucial to monitor future application development. For PEF (polyethylene furanoate, a particular approach for contamination-related issues has been included in the upcoming market introduction. With respect to developing policy, it is important that any introduction of novel plastics is well guided from a system perspective and with a particular eye on incompatibilities with current and upcoming practices in the recycling of plastics.
Plastic condoms.

Science.gov (United States)

1968-01-01

Only simple equipment, simple technology and low initial capital investment are needed in their manufacture. The condoms can be made by people who were previously unskilled or only semi-skilled workers. Plastic condoms differ from those made of latex rubber in that the nature of the plastic film allows unlimited shelf-life. Also, the plastic has a higher degree of lubricity than latex rubber; if there is a demand for extra lubrication in a particular market, this can be provided. Because the plastic is inert, these condoms need not be packaged in hermetically sealed containers. All these attributes make it possible to put these condoms on the distributors' shelves in developing countries competitively with rubber condoms. The shape of the plastic condom is based on that of the lamb caecum, which has long been used as luxury-type condom. The plastic condom is made from plastic film (ethylene ethyl acrilate) of 0.001 inch (0.0254 mm.) thickness. In addition, a rubber ring is provided and sealed into the base of the condom for retention during coitus. The advantage of the plastic condom design and the equipment on which it is made is that production can be carried out either in labour-intensive economy or with varying degrees of mechanization and automation. The uniform, finished condom if made using previously untrained workers. Training of workers can be done in a matter of hours on the two machines which are needed to produce and test the condoms. The plastic film is provided on a double wound roll, and condom blanks are prepared by means of a heat-sealing die on the stamping machine. The rubber rings are united to the condom blanks on an assembly machine, which consists of a mandrel and heat-sealing equipment to seal the rubber ring to the base of the condom. Built into the assembly machine is a simple air-testing apparatus that can detect the smallest pinhole flaw in a condom. The manufacturing process is completed by unravelling the condom from the assembly
Biodegradability of plastics.

Science.gov (United States)

Tokiwa, Yutaka; Calabia, Buenaventurada P; Ugwu, Charles U; Aiba, Seiichi

2009-08-26

Plastic is a broad name given to different polymers with high molecular weight, which can be degraded by various processes. However, considering their abundance in the environment and their specificity in attacking plastics, biodegradation of plastics by microorganisms and enzymes seems to be the most effective process. When plastics are used as substrates for microorganisms, evaluation of their biodegradability should not only be based on their chemical structure, but also on their physical properties (melting point, glass transition temperature, crystallinity, storage modulus etc.). In this review, microbial and enzymatic biodegradation of plastics and some factors that affect their biodegradability are discussed.
samaru-main-vol 11 2011

African Journals Online (AJOL)

Library _info_Sc_ 1

2004-07-11

Jul 11, 2004 ... Samaru Journal of Information Studies Vol. 11 (1 & 2)2011 ... It is therefore paramount that the library ... source of primary and up to date information, both students and ... entertainment, arts, fashion, law, economy, medicine,.
Characterization of plastic blends made from mixed plastics waste of different sources.

Science.gov (United States)

Turku, Irina; Kärki, Timo; Rinne, Kimmo; Puurtinen, Ari

2017-02-01

This paper studies the recyclability of construction and household plastic waste collected from local landfills. Samples were processed from mixed plastic waste by injection moulding. In addition, blends of pure plastics, polypropylene and polyethylene were processed as a reference set. Reference samples with known plastic ratio were used as the calibration set for quantitative analysis of plastic fractions in recycled blends. The samples were tested for the tensile properties; scanning electron microscope-energy-dispersive X-ray spectroscopy was used for elemental analysis of the blend surfaces and Fourier transform infrared (FTIR) analysis was used for the quantification of plastics contents.
The Prevalence of Cosmetic Facial Plastic Procedures among Facial Plastic Surgeons.

Science.gov (United States)

Moayer, Roxana; Sand, Jordan P; Han, Albert; Nabili, Vishad; Keller, Gregory S

2018-04-01

This is the first study to report on the prevalence of cosmetic facial plastic surgery use among facial plastic surgeons. The aim of this study is to determine the frequency with which facial plastic surgeons have cosmetic procedures themselves. A secondary aim is to determine whether trends in usage of cosmetic facial procedures among facial plastic surgeons are similar to that of nonsurgeons. The study design was an anonymous, five-question, Internet survey distributed via email set in a single academic institution. Board-certified members of the American Academy of Facial Plastic and Reconstructive Surgery (AAFPRS) were included in this study. Self-reported history of cosmetic facial plastic surgery or minimally invasive procedures were recorded. The survey also queried participants for demographic data. A total of 216 members of the AAFPRS responded to the questionnaire. Ninety percent of respondents were male ( n = 192) and 10.3% were female ( n = 22). Thirty-three percent of respondents were aged 31 to 40 years ( n = 70), 25% were aged 41 to 50 years ( n = 53), 21.4% were aged 51 to 60 years ( n = 46), and 20.5% were older than 60 years ( n = 44). Thirty-six percent of respondents had a surgical cosmetic facial procedure and 75% has at least one minimally invasive cosmetic facial procedure. Facial plastic surgeons are frequent users of cosmetic facial plastic surgery. This finding may be due to access, knowledge base, values, or attitudes. By better understanding surgeon attitudes toward facial plastic surgery, we can improve communication with patients and delivery of care. This study is a first step in understanding use of facial plastic procedures among facial plastic surgeons. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.
Vol 12, No 1 (2014)

African Journals Online (AJOL)

Egyptian Journal of Pediatric Allergy and Immunology (The) - Vol 12, No 1 (2014) ... The effect of serum angiotensin II and angiotensin II type 1 receptor gene ... with diabetic ketoacidosis · EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT
Recycling of plastic waste: Presence of phthalates in plastics from households and industry.

Science.gov (United States)

Pivnenko, K; Eriksen, M K; Martín-Fernández, J A; Eriksson, E; Astrup, T F

2016-08-01

Plastics recycling has the potential to substitute virgin plastics partially as a source of raw materials in plastic product manufacturing. Plastic as a material may contain a variety of chemicals, some potentially hazardous. Phthalates, for instance, are a group of chemicals produced in large volumes and are commonly used as plasticisers in plastics manufacturing. Potential impacts on human health require restricted use in selected applications and a need for the closer monitoring of potential sources of human exposure. Although the presence of phthalates in a variety of plastics has been recognised, the influence of plastic recycling on phthalate content has been hypothesised but not well documented. In the present work we analysed selected phthalates (DMP, DEP, DPP, DiBP, DBP, BBzP, DEHP, DCHP and DnOP) in samples of waste plastics as well as recycled and virgin plastics. DBP, DiBP and DEHP had the highest frequency of detection in the samples analysed, with 360μg/g, 460μg/g and 2700μg/g as the maximum measured concentrations, respectively. Among other, statistical analysis of the analytical results suggested that phthalates were potentially added in the later stages of plastic product manufacturing (labelling, gluing, etc.) and were not removed following recycling of household waste plastics. Furthermore, DEHP was identified as a potential indicator for phthalate contamination of plastics. Close monitoring of plastics intended for phthalates-sensitive applications is recommended if recycled plastics are to be used as raw material in production. Copyright © 2016 Elsevier Ltd. All rights reserved.
Recycling of plastic waste: Presence of phthalates in plastics from households and industry

DEFF Research Database (Denmark)

Pivnenko, Kostyantyn; Eriksen, Marie Kampmann; Martín-Fernández, J. A.

2016-01-01

Plastics recycling has the potential to substitute virgin plastics partially as a source of raw materials in plastic product manufacturing. Plastic as a material may contain a variety of chemicals, some potentially hazardous. Phthalates, for instance, are a group of chemicals produced in large...... recognised, the influence of plastic recycling on phthalate content has been hypothesised but not well documented. In the present work we analysed selected phthalates (DMP, DEP, DPP, DiBP, DBP, BBzP, DEHP, DCHP and DnOP) in samples of waste plastics as well as recycled and virgin plastics. DBP, DiBP and DEHP...
Biodegradability of Plastics

Directory of Open Access Journals (Sweden)

Yutaka Tokiwa

2009-08-01

Full Text Available Plastic is a broad name given to different polymers with high molecular weight, which can be degraded by various processes. However, considering their abundance in the environment and their specificity in attacking plastics, biodegradation of plastics by microorganisms and enzymes seems to be the most effective process. When plastics are used as substrates for microorganisms, evaluation of their biodegradability should not only be based on their chemical structure, but also on their physical properties (melting point, glass transition temperature, crystallinity, storage modulus etc.. In this review, microbial and enzymatic biodegradation of plastics and some factors that affect their biodegradability are discussed.
Elastic-plastic behaviour of thick-walled containers considering plastic compressibility

International Nuclear Information System (INIS)

Betten, J.; Frosch, H.G.

1983-01-01

In this paper the elastic-plastic behaviour of thick-walled pressure vessels with internal and external pressure is studied. To describe the mechanical behaviour of isotropic, plastic compressible materials we use a plastic potential which is a single-valued function of the principle stresses. For cylinders and spheres an analytic expression for the computation of stresses and residual stresses is specified. Afterwards the strains are calculated by using the finite difference method. Some examples will high-light the influence of the plastic compressibility on the behaviour of pressure vessels. (orig.) [de
Mechanically equivalent elastic-plastic deformations and the problem of plastic spin

Directory of Open Access Journals (Sweden)

Steigmann David J.

2011-01-01

Full Text Available The problem of plastic spin is phrased in terms of a notion of mechanical equivalence among local intermediate configurations of an elastic/ plastic crystalline solid. This idea is used to show that, without further qualification, the plastic spin may be suppressed at the constitutive level. However, the spin is closely tied to an underlying undistorted crystal lattice which, once specified, eliminates the freedom afforded by mechanical equivalence. As a practical matter a constitutive specification of plastic spin is therefore required. Suppression of plastic spin thus emerges as merely one such specification among many. Restrictions on these are derived in the case of rate-independent response.
Plastics and health risks.

Science.gov (United States)

Halden, Rolf U

2010-01-01

By 2010, the worldwide annual production of plastics will surpass 300 million tons. Plastics are indispensable materials in modern society, and many products manufactured from plastics are a boon to public health (e.g., disposable syringes, intravenous bags). However, plastics also pose health risks. Of principal concern are endocrine-disrupting properties, as triggered for example by bisphenol A and di-(2-ethylhexyl) phthalate (DEHP). Opinions on the safety of plastics vary widely, and despite more than five decades of research, scientific consensus on product safety is still elusive. This literature review summarizes information from more than 120 peer-reviewed publications on health effects of plastics and plasticizers in lab animals and humans. It examines problematic exposures of susceptible populations and also briefly summarizes adverse environmental impacts from plastic pollution. Ongoing efforts to steer human society toward resource conservation and sustainable consumption are discussed, including the concept of the 5 Rs--i.e., reduce, reuse, recycle, rethink, restrain--for minimizing pre- and postnatal exposures to potentially harmful components of plastics.

Recycling of plastic waste: Presence of phthalates in plastics from households and industry

DEFF Research Database (Denmark)

Pivnenko, Kostyantyn; Eriksen, Marie Kampmann; Martín-Fernández, J. A.

2016-01-01

recognised, the influence of plastic recycling on phthalate content has been hypothesised but not well documented. In the present work we analysed selected phthalates (DMP, DEP, DPP, DiBP, DBP, BBzP, DEHP, DCHP and DnOP) in samples of waste plastics as well as recycled and virgin plastics. DBP, DiBP and DEHP...... product manufacturing (labelling, gluing, etc.) and were not removed following recycling of household waste plastics. Furthermore, DEHP was identified as a potential indicator for phthalate contamination of plastics. Close monitoring of plastics intended for phthalates-sensitive applications...
Anestesia volátil e monitorização anestésica.

OpenAIRE

Alexandre, Nuno; Costa, Margarida; Mascarenhas, Ramiro

2009-01-01

Os autores apresentam um texto de apoio à disciplina de anestesiologia do curso de Medicina Veterinária .Neste texto são abordadas diversas temáticas da anestesia volátil tais como: equipamentos utilizados em anestesia volátil, farmacologia dos anestésicos voláteis. A monitorização dos pacientes é abordada na vertente mecânica ou intrumental e na componente básica.
Index to Nuclear Safety: a technical progress review by chronology, permuted title, and author. Vol. 11(1)--Vol. 18(6)

Energy Technology Data Exchange (ETDEWEB)

Cottrell, W.B.; Klein, A.

1978-04-11

This index to Nuclear Safety covers articles published in Nuclear Safety, Vol. 11, No. 1 (January-February 1970), through Vol. 18, No. 6 (November-December 1977). It is divided into three sections: a chronological list of articles (including abstracts) followed by a permuted-title (KWIC) index and an author index. Nuclear Safety, a bimonthly technical progress review prepared by the Nuclear Safety Information Center (NSIC), covers all safety aspects of nuclear power reactors and associated facilities. Over 450 technical articles published in Nuclear Safety in the last eight years are listed in this index.
Index to Nuclear Safety: a technical progress review by chronology, permuted title, and author. Vol. 11(1)--Vol. 18(6)

International Nuclear Information System (INIS)

Cottrell, W.B.; Klein, A.

1978-01-01

This index to Nuclear Safety covers articles published in Nuclear Safety, Vol. 11, No. 1 (January-February 1970), through Vol. 18, No. 6 (November-December 1977). It is divided into three sections: a chronological list of articles (including abstracts) followed by a permuted-title (KWIC) index and an author index. Nuclear Safety, a bimonthly technical progress review prepared by the Nuclear Safety Information Center (NSIC), covers all safety aspects of nuclear power reactors and associated facilities. Over 450 technical articles published in Nuclear Safety in the last eight years are listed in this index
Ethiopian Journal of Health Sciences - Vol 28, No 2 (2018)

African Journals Online (AJOL)

Ethiopian Journal of Health Sciences - Vol 28, No 2 (2018). Journal Home > Archives > Vol 28, No 2 (2018). Log in or Register to get access to full text downloads. ... Prevalence of opportunistic intestinal parasites and associated factors among HIV patients while receiving ART at Arba Minch Hospital in southern Ethiopia: a ...
Chemistry and physics

International Nuclear Information System (INIS)

Broerse, J.J.; Barendsen, G.W.; Kal, H.B.; Kogel, A.J. van der

1983-01-01

This book contains the extended abstracts of the contributions of the poster workshop sessions on chemistry and physics of the 7th international congress of radiation research. They cover the following main topics: primary processes in radiation physics and chemistry, general chemistry in radiation chemistry, DNA and model systems in radiation chemistry, molecules of biological interest in radiation chemistry, techniques in radiation chemistry, hot atom chemistry. refs.; figs.; tabs
Fiscal 1999 survey report. Part 2. Research study on restraint of carbon dioxide generation by green chemistry; 1999 nendo green chemistry ni yoru CO{sub 2} hassei yokusei ni kakawaru chosa kenkyu. 2

Energy Technology Data Exchange (ETDEWEB)

NONE

2000-03-01

In connection with green chemistry, a concept of bringing paradigm shift to chemical technologies as something that makes reduction in environmental load compatible with economic activities; surveys were made this year on the developments of fine chemicals from renewable resources such as cellulose among the cases of developing chemical substances/products to be called 'green chemicals' reducing environmental load; developments of surfactants produced by certain microorganism, plastic additives with reduced pollutant loads, particularly fire retardants and environmentally benign reactant solvents; concept of green chemistry in the development of chlorofluorocarbon-alternatives; and up-to-date technological level concerning a design method of chemical materials and an estimation method for chemical safety using quantum chemistry calculation. In regard to the chemical materials and products intrinsically containing a certain level of risk, R and D should be reinforced and accelerated in the future on the alternative materials/products reducing their toxicity. In this case, along with the importance of discussing compatibility of technological possibility with economical adaptability, sociological study seems to be necessary in incorporating environmental load reduction into economic evaluation. (NEDO)
Challenges in plastics recycling

DEFF Research Database (Denmark)

Pivnenko, Kostyantyn; Jakobsen, L. G.; Eriksen, Marie Kampmann

2015-01-01

Recycling of waste plastics still remains a challenging area in the waste management sector. The current and potential goals proposed on EU or regional levels are difficult to achieve, and even to partially fullfil them the improvements in collection and sorting should be considerable. A study...... was undertaken to investigate the factors affecting quality in plastics recycling. The preliminary results showed factors primarily influencing quality of plastics recycling to be polymer cross contamination, presence of additives, non-polymer impurities, and polymer degradation. Deprivation of plastics quality......, with respect to recycling, has been shown to happen throughout the plastics value chain, but steps where improvements may happen have been preliminary identified. Example of Cr in plastic samples analysed showed potential spreading and accumulation of chemicals ending up in the waste plastics. In order...
Individual differences in behavioural plasticities.

Science.gov (United States)

Stamps, Judy A

2016-05-01

Interest in individual differences in animal behavioural plasticities has surged in recent years, but research in this area has been hampered by semantic confusion as different investigators use the same terms (e.g. plasticity, flexibility, responsiveness) to refer to different phenomena. The first goal of this review is to suggest a framework for categorizing the many different types of behavioural plasticities, describe examples of each, and indicate why using reversibility as a criterion for categorizing behavioural plasticities is problematic. This framework is then used to address a number of timely questions about individual differences in behavioural plasticities. One set of questions concerns the experimental designs that can be used to study individual differences in various types of behavioural plasticities. Although within-individual designs are the default option for empirical studies of many types of behavioural plasticities, in some situations (e.g. when experience at an early age affects the behaviour expressed at subsequent ages), 'replicate individual' designs can provide useful insights into individual differences in behavioural plasticities. To date, researchers using within-individual and replicate individual designs have documented individual differences in all of the major categories of behavioural plasticities described herein. Another important question is whether and how different types of behavioural plasticities are related to one another. Currently there is empirical evidence that many behavioural plasticities [e.g. contextual plasticity, learning rates, IIV (intra-individual variability), endogenous plasticities, ontogenetic plasticities) can themselves vary as a function of experiences earlier in life, that is, many types of behavioural plasticity are themselves developmentally plastic. These findings support the assumption that differences among individuals in prior experiences may contribute to individual differences in behavioural
Dynamics of structures '89. Vol. 1 and 2

International Nuclear Information System (INIS)

1989-01-01

The proceedings, comprising 3 volumes published by the Plzen Centre of the Czechoslovak Society for Science and Technology (Vol. 1 and 2) and by Skoda Works in Plzen (Vol. 3), contain 107 papers, out of which 8 fall within the INIS Subject Scope; these deal with problems related to the earthquake resistance of nuclear power plants. Attention is paid to the evaluation of seismic characteristics of nuclear power plant equipment, to the equipment testing and to calculations of its dynamic characteristics under simulated seismic stress. (Z.M.)
Durability of wood plastic composites manufactured from recycled plastic

Directory of Open Access Journals (Sweden)

Irina Turku

2018-03-01

Full Text Available The influence of accelerated weathering, xenon-arc light and freeze-thaw cycling on wood plastic composites extruded from a recycled plastic was studied. The results showed that, in general, weathering had a stronger impact on samples made from plastic waste compared to a sample made from virgin material. After weathering, the mechanical properties, tensile and flexural, were reduced by 2–30%, depending on the plastic source. Wettability of the samples was shown to play a significant role in their stability. Chemical analysis with infrared spectroscopy and surface observation with a scan electron microscope confirmed the mechanical test results. Incorporation of carbon black retained the properties during weathering, reducing the wettability of the sample, diminishing the change of mechanical properties, and improving color stability. Keywords: Environmental science, Mechanical engineering, Materials science
Phenotypic plasticity, costs of phenotypes, and costs of plasticity

DEFF Research Database (Denmark)

Callahan, Hilary S; Maughan, Heather; Steiner, Uli

2008-01-01

Why are some traits constitutive and others inducible? The term costs often appears in work addressing this issue but may be ambiguously defined. This review distinguishes two conceptually distinct types of costs: phenotypic costs and plasticity costs. Phenotypic costs are assessed from patterns...... of covariation, typically between a focal trait and a separate trait relevant to fitness. Plasticity costs, separable from phenotypic costs, are gauged by comparing the fitness of genotypes with equivalent phenotypes within two environments but differing in plasticity and fitness. Subtleties associated with both...... types of costs are illustrated by a body of work addressing predator-induced plasticity. Such subtleties, and potential interplay between the two types of costs, have also been addressed, often in studies involving genetic model organisms. In some instances, investigators have pinpointed the mechanistic...
Plastic waste as a resource. Strategies for reduction and utilization of plastic waste

OpenAIRE

Pasqual i Camprubí, Gemma

2010-01-01

Plastic materials have experienced a spectacular rate of growth in recent decades, consequently, production of plastics, and likewise their consumption, has increased markedly since 1950. Moreover, they are lightweight and durable, as well as can be moulded into a variety of products that can be manufactured in many different types of plastic and in a wide range of applications. Inevitably, continually increasing amounts of used plastic are originating daily, resulting in a plastic waste prob...
Large hadron collider workshop. Proceedings. Vol. 3

International Nuclear Information System (INIS)

Jarlskog, G.; Rein, D.

1990-01-01

The aim of the LHC workshop at Aachen was to discuss the 'discovery potential' of a high-luminosity hadron collider (the Large Hadron Collider) and to define the requirements of the detectors. Of central interest was whether a Higgs particle with mass below 1 TeV could be seen using detectors potentially available within a few years from now. Other topics included supersymmetry, heavy quarks, excited gauge bosons, and exotica in proton-proton collisions, as well as physics to be observed in electron-proton and heavy-ion collisions. A large part of the workshop was devoted to the discussion of instrumental and detector concepts, including simulation, signal processing, data acquisition, tracking, calorimetry, lepton identification and radiation hardness. The workshop began with parallel sessions of working groups on physics and instrumentaiton and continued, in the second half, with plenary talks giving overviews of the LHC project and the SSC, RHIC, and HERA programmes, summaries of the working groups, presentations from industry, and conclusions. Vol. 1 of these proceedings contains the papers presented at the plenary sessions, Vol. 2 the individual contributions to the physics sessions, and Vol. 3 those to the instrumentation sessions. (orig.)
Large hadron collider workshop. Proceedings. Vol. 2

International Nuclear Information System (INIS)

Jarlskog, G.; Rein, D.

1990-01-01

The aim of the LHC workshop at Aachen was to discuss the 'discovery potential' of a high-luminosity hadron collider (the Large Hadron Collider) and to define the requirements of the detectors. Of central interest was whether a Higgs particle with mass below 1 TeV could be seen using detectors potentially available within a few years from now. Other topics included supersymmetry, heavy quarks, excited gauge bosons, and exotica in proton-proton collisions, as well as physics to be observed in electron-proton and heavy-ion collisions. A large part of the workshop was devoted to the discussion of instrumental and detector concepts, including simulation, signal processing, data acquisition, tracking, calorimetry, lepton identification and radiation hardness. The workshop began with parallel sessions of working groups on physics and instrumentation and continued, in the second half, with plenary talks giving overviews of the LHC project and the SSC, RHIC, and HERA programmes, summaries of the working groups, presentations from industry, and conclusions. Vol.1 of these proceedings contains the papers presented at the plenary sessions, Vol.2 the individual contributions to the physics sessions, and Vol.3 those to the instrumentation sessions. (orig.)
Large hadron collider workshop. Proceedings. Vol. 1

International Nuclear Information System (INIS)

Jarlskog, G.; Rein, D.

1990-01-01

The aim of the LCH workshop at Aachen was to discuss the 'discovery potential' of a high-luminosity hadron collider (the Large Hadron Collider) and to define the requirements of the detectors. Of central interest was whether a Higgs particle with mass below 1 TeV could be seen using detectors potentially available within a few years from now. Other topics included supersymmetry, heavy quarks, excited gauge bosons, and exotica in proton-proton collisions, as well as physics to be observed in electron-proton and heavy-ion collisions. A large part of the workshop was devoted to the discussion of instrumental and detector concepts, including simulation, signal processing, data acquisition, tracking, calorimetry, lepton identification and radiation hardness. The workshop began with parallel sessions of working groups on physics and instrumentation and continued, in the second half, with plenary talks giving overviews of the LHC project and the SSC, RHIC, and HERA programmes, summaries of the working groups, presentations from industry, and conclusions. Vol. 1 of these proceedings contains the papers presented at the plenary sessions, Vol. 2 the individual contributions to the physics sessions, and Vol. 3 those to the instrumentation sessions. (orig.)
Thermal degradation and plasticizing mechanism of poly(vinyl chloride) plasticized with a novel cardanol derived plasticizer

Science.gov (United States)

Chen, J.; Nie, X. A.; Jiang, J. C.; Zhou, Y. H.

2018-01-01

A natural plasticizer cardanol derivatives glycidyl ether (CGE) was synthesized and employed as a plasticizer for the poly(vinyl chloride). The effect of CGE on thermal degradation of PVC films and its plasticizing mechanism were firstly reported. The molecular structure of CGE was characterized with Fourier transform infrared spectroscopy (FTIR). Thermal properties, degradation properties and compatibility of the PVC films were investigated by Differential scanning calorimeter analysis (DSC), Thermogravimetric analysis (TGA) and FTIR, respectively. Compared with the commercial plasticizers dioctylphthalate (DOP), CGE can endow PVC film with a decrease of 4.31 °C in glass transition temperature (Tg), an increase of 24.01 °C and 25.53 °C in 10% weight loss (T 10) and 50% weight loss (T 50) respectively, and a higher activetion energy of thermal degradation (Ea ).
From hot atom chemistry to epithermal chemistry

International Nuclear Information System (INIS)

Roessler, K.

2004-01-01

The rise and fall of hot atom chemistry (HAC) over the years from 1934 to 2004 is reviewed. Several applications are discussed, in particular to astrophysics and the interaction of energetic ions and atoms in space. Epithermal chemistry (ETC) is proposed to substitute the old name, since it better fits the energy range as well as the non-thermal and non-equilibrium character of the reactions. ETC also avoids the strong connexion of HAC to nuclear chemistry and stands for the opening of the field to physical chemistry and astrophysics. (orig.)
Mathematical Chemistry

OpenAIRE

Trinajstić, Nenad; Gutman, Ivan

2002-01-01

A brief description is given of the historical development of mathematics and chemistry. A path leading to the meeting of these two sciences is described. An attempt is made to define mathematical chemistry, and journals containing the term mathematical chemistry in their titles are noted. In conclusion, the statement is made that although chemistry is an experimental science aimed at preparing new compounds and materials, mathematics is very useful in chemistry, among other things, to produc...
Errata Resonance, Vol.20, No.12, 2015. Rajaram Nityananda, Sun ...

Indian Academy of Sciences (India)

IAS Admin

Resonance, Vol.20, No.12, 2015. Rajaram Nityananda, Sun, Sky and Clouds: Where Light and Matter Meet. Page 1121: The correct Figure 5 is reproduced below: Resonance, Vol.20, No.11, 2015. Anil Kumar, Felix Bloch (1905–1983). Page 956: Para 1, Line 5, 'also from Zürich' should be read as 'from nearby Bern'.

The Hugoniot and chemistry of ablator plastic below 100 GPa

Energy Technology Data Exchange (ETDEWEB)

Akin, M. C., E-mail: akin1@llnl.gov; Fratanduono, D. E.; Chau, R. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States)

2016-01-28

The equation of state of glow discharge polymer (GDP) was measured to high precision using the two-stage light gas gun at Lawrence Livermore National Laboratory at pressures up to 70 GPa. Both absolute measurements and impedance matching techniques were used to determine the principal and secondary Hugoniots. GDP likely reacts at about 30 GPa, demonstrated by specific emission at 450 nm coupled with changes to the Hugoniot and reshock points. As a result of these reactions, the shock pressure in GDP evolves in time, leading to a possible decrease in pressure as compression increases, or negative compressibility, and causing complex pressure profiles within the plastic. Velocity wave profile variation was observed as a function of position on each shot, suggesting some internal variation of GDP may be present, which would be consistent with previous observations. The complex temporal and possibly structural evolution of GDP under shock compression suggests that calculations of compression and pressure based upon bulk or mean measurements may lead to artificially low pressures and high compressions. Evidence for this includes a large shift in calculating reshock pressures based on the reflected Hugoniot. These changes also suggest other degradation mechanisms for inertial confinement fusion implosions.
Mixed plastics recycling technology

CERN Document Server

Hegberg, Bruce

1995-01-01

Presents an overview of mixed plastics recycling technology. In addition, it characterizes mixed plastics wastes and describes collection methods, costs, and markets for reprocessed plastics products.
Information manager-2011-Vol 11

African Journals Online (AJOL)

Library _info_Sc_ 1

The Information Manager Vol. ... extent while carrying out their duties on a daily basis. ... It concluded by admonishing librarians to brace up and keep pace ... Proper training should be given to .... used to information and communication technologies .... proficiency Skills .... analysis of the workplace and implementation of.
Sub-nanosecond plastic scintillators

International Nuclear Information System (INIS)

Lyons, P.B.; Caldwell, S.E.; Hocker, L.P.; Crandall, D.G.; Zagarino, P.A.; Cheng, J.; Tirsell, G.; Hurlbut, C.R.

1977-01-01

Quenched plastic scintillators have been developed that yield much faster short decay components and greatly reduced long decay components compared to conventional plastic scintillators. The plastics are produced through the addition of selected quench agents to NE111 plastic scintillator that result in reduced total light output. Eight different agents have been studied. Benzophenone and piperidine are two of the most effective quench agents. Data are presented both for short and long decay components. The plastics are expected to make significant contributions in areas of plasma diagnostics
Sub-nanosecond plastic scintillators

International Nuclear Information System (INIS)

Lyons, P.B.; Caldwell, S.E.; Hocker, L.P.; Crandall, D.G.; Zagarino, P.A.; Cheng, J.; Tirsell, G.; Hurlbut, C.R.

1976-01-01

Quenched plastic scintillators have been developed that yield much faster short decay components and greatly reduced long decay components compared to conventional plastic scintillators. The plastics are produced through the addition of selected quench agents to NE111 plastic scintillator that result in reduced total light output. Eight different agents have been studied. Benzophenone and piperidine are two of the most effective quench agents. Data are presented both for short and long decay components. The plastics are expected to make significant contributions in areas of plasma diagnostics
Ocean Literacy from kindergarten to secondary school: a vertically articulated curriculum on marine micro-plastics

Science.gov (United States)

Realdon, Giulia; Candussio, Giuliana; Manià, Marinella; Palamin, Serenella

2017-04-01

Marine micro-plastics are a relatively recent issue in research (Thompson et al. 2004), in the media and in education and, due to novelty and relevance, they are a suitable topic for addressing Ocean Literacy within science teaching to different age groups. In fact marine micro-plastics can be used to introduce Ocean Literacy and environmental science, but also traditional science subjects like biology, chemistry and Earth science, with a system approach focused on "understanding the Ocean's influence on humans and human influence on the Ocean". Inspired by the growing public interest for marine micro-plastics and by the lack of specific teaching activities in our country (Italy), we developed a vertically articulated curriculum on micro-plastics for students aged 5-15 years. Our proposal is based on a number of practical activities realized with different language and communication styles to be suitable for different age groups. For younger students (age 5-7) we use drama to address micro-plastics bioaccumulation in marine food chains: children act as fish of different trophic levels who pretend to "eat" micro-plastics models (built from plastic bottles) until the biggest fish is captured and ends up as a "meal" shared by other pupils. Teachers guide the performance and stimulate observations and remarks about the origin of micro-plastics and the correct management of plastic objects. The performance has been documented in a video and presented in a national teacher workshop (3 Giorni per la Scuola, Napoli 2015). For students aged 8-13 we propose observation and manipulation of common household plastic objects, followed by physical/chemical testing of different polymers to understand plastics characteristics that make these materials valuable but troublesome at the same time. Students then observe sand samples, taken from a local beach, containing natural components and man-made fragments (including micro-plastics), so they can directly experience the fate of
Browse Title Index

African Journals Online (AJOL)

Items 101 - 130 of 130 ... Vol 6, No 2 (2016), Uses of systemic approach and chemist's triangle in teaching and learning chemistry: Systemic Chemistry Triangle [SCT] as a teaching & learning strategy, Abstract PDF. A.F.M. Fahmy. Vol 3, No 2 (2013), Using stereochemistry models in teaching organic compounds nomenclature: ...
Time between plastic displacements of elasto-plastic oscillators subject to Gaussian white noise

DEFF Research Database (Denmark)

Tarp-Johansen, Niels Jacob; Ditlevsen, Ove Dalager

2001-01-01

A one degree of freedom elasto-plastic oscillator subject to stationary Gaussian white noise has a plastic displacement response process of intermittent character. During shorter or longer time intervals the oscillator vibrates within the elastic domain without undergoing any plastic displacements...... between the clumps of plastic displacements. This is needed for a complete description of the plastic displacement process. A quite accurate fast simulation procedure is presented based on an amplitude model to determine the short waiting times in the transient regime of the elastic vibrations existing...
Index to Nuclear Safety. A technical progress review by chronology, permuted title, and author. Vol. 11, No. 1--Vol. 17, No. 6

International Nuclear Information System (INIS)

Cottrell, W.B.; Klein, A.

1977-01-01

This index to Nuclear Safety covers articles in Nuclear Safety Vol. 11, No. 1 (Jan.-Feb. 1970), through Vol. 17, No. 6 (Nov.-Dec. 1976). The index includes a chronological list of articles (including abstract) followed by KWIC and Author Indexes. Nuclear Safety, a bimonthly technical progress review prepared by the Nuclear Safety Information Center, covers all safety aspects of nuclear power reactors and associated facilities. The index lists over 350 technical articles in the last six years of publication
Index to Nuclear Safety. A technical progress review by chronology, permuted title, and author. Vol. 11, No. 1--Vol. 17, No. 6

Energy Technology Data Exchange (ETDEWEB)

Cottrell, W.B.; Klein, A.

1977-02-23

This index to Nuclear Safety covers articles in Nuclear Safety Vol. 11, No. 1 (Jan.-Feb. 1970), through Vol. 17, No. 6 (Nov.-Dec. 1976). The index includes a chronological list of articles (including abstract) followed by KWIC and Author Indexes. Nuclear Safety, a bimonthly technical progress review prepared by the Nuclear Safety Information Center, covers all safety aspects of nuclear power reactors and associated facilities. The index lists over 350 technical articles in the last six years of publication.
[Application of biodegradable plastic film to reduce plastic film residual pollution in Chinese agriculture].

Science.gov (United States)

Yan, Changrong; He, Wenqing; Xue, Yinghao; Liu, Enke; Liu, Qin

2016-06-25

Plastic film has become an important agriculture production material in recent years. Over the past three decades, the amount and application area of plastic film have increased steadily, and in 2014, which are 1.4 million tons and more than 180 million hm² respectively. It plays a key role for ensuring the supply of agricultural goods in China. Meanwhile, plastic film residual pollution becomes more and more serious, and in some regions, the amount of plastic film residues has reached over 250 kg/hm². In part of the Northwest region, soil structure of farmland has been destroyed by plastic film residues and then crop growth and farming operations were suppressed. It is recognized as a good choice to replace plastic film with biodegradable plastic film, an effective measure to solve the plastic film residue pollution. Now, it is in a critical stage of study and assessment of biodegradable plastic film in China and fortunately some biodegradable plastic films show effects in the production of potatoes, peanuts and tobacco. Overall, a series of challenges has still been faced by the biodegradable plastic film, mainly including improving the quality of biodegradable plastic products, such as tensile strength, flexibility, improving the controllability of rupture and degradation, enhancing the ability of increasing soil temperature and preserving soil moisture, and to satisfy the demand of crops production with mulching. In addition, it is essential to reduce the cost of the biodegradable film and promote the application of biodegradable film on large-scale. With the development of biodegradable plastic technology and agricultural production environment, the application of the biodegradable film will have a good future.
Industrial chemistry engineering

International Nuclear Information System (INIS)

1993-01-01

This book on industrial chemistry engineering is divided in two parts. The first part deals with industrial chemistry, inorganic industrial chemistry, organic industrial chemistry, analytical chemistry and practical questions. The last parts explain the chemical industry, a unit parts and thermodynamics in chemical industry and reference. It reveals the test subjects for the industrial chemistry engineering with a written examination and practical skill.
Advanced chemistry management system to optimize BWR chemistry control

International Nuclear Information System (INIS)

Maeda, K.; Nagasawa, K.

2002-01-01

BWR plant chemistry control has close relationships among nuclear safety, component reliability, radiation field management and fuel integrity. Advanced technology is required to improve chemistry control [1,3,6,7,10,11]. Toshiba has developed TACMAN (Toshiba Advanced Chemistry Management system) to support BWR chemistry control. The TACMAN has been developed as response to utilities' years of requirements to keep plant operation safety, reliability and cost benefit. The advanced technology built into the TACMAN allows utilities to make efficient chemistry control and to keep cost benefit. TACMAN is currently being used in response to the needs for tools those plant chemists and engineers could use to optimize and identify plant chemistry conditions continuously. If an incipient condition or anomaly is detected at early stage, root causes evaluation and immediate countermeasures can be provided. Especially, the expert system brings numerous and competitive advantages not only to improve plant chemistry reliability but also to standardize and systematize know-how, empirical knowledge and technologies in BWR chemistry This paper shows detail functions of TACMAN and practical results to evaluate actual plant. (authors)
Plastic fish

CERN Multimedia

Antonella Del Rosso

2015-01-01

In terms of weight, the plastic pollution in the world’s oceans is estimated to be around 300,000 tonnes. This plastic comes from both land-based and ocean-based sources. A lecture at CERN by chemist Wolfgang Trettnak addressed this issue and highlighted the role of art in raising people’s awareness. Artwork by Wolfgang Trettnak. Packaging materials, consumer goods (shoes, kids’ toys, etc.), leftovers from fishing and aquaculture activities… our oceans and beaches are full of plastic litter. Most of the debris from beaches is plastic bottles. “PET bottles have high durability and stability,” explains Wolfgang Trettnak, a chemist by education and artist from Austria, who gave a lecture on this topic organised by the Staff Association at CERN on 26 May. “PET degrades very slowly and the estimated lifetime of a bottle is 450 years.” In addition to the beach litter accumulated from human use, rivers bring several ki...
NJB VOL.34 Original Lower.cdr

African Journals Online (AJOL)

important sources of renewable biological ... The plantain (Musa paradisiaca) and banana chemicals (Nowak et ... fermentable sugars available for bio-ethanol ..... peels. Afr. J. Biochem. Res. 9(9): 104 - 109. 70. Osho et al./ Nig. J. Biotech. Vol.
Plastics in the Marine Environment.

Science.gov (United States)

Law, Kara Lavender

2017-01-03

Plastics contamination in the marine environment was first reported nearly 50 years ago, less than two decades after the rise of commercial plastics production, when less than 50 million metric tons were produced per year. In 2014, global plastics production surpassed 300 million metric tons per year. Plastic debris has been detected worldwide in all major marine habitats, in sizes from microns to meters. In response, concerns about risks to marine wildlife upon exposure to the varied forms of plastic debris have increased, stimulating new research into the extent and consequences of plastics contamination in the marine environment. Here, I present a framework to evaluate the current understanding of the sources, distribution, fate, and impacts of marine plastics. Despite remaining knowledge gaps in mass budgeting and challenges in investigating ecological impacts, the increasing evidence of the ubiquity of plastics contamination in the marine environment, the continued rapid growth in plastics production, and the evidence-albeit limited-of demonstrated impacts to marine wildlife support immediate implementation of source-reducing measures to decrease the potential risks of plastics in the marine ecosystem.
Plastics in the Marine Environment

Science.gov (United States)

Law, Kara Lavender

2017-01-01

Plastics contamination in the marine environment was first reported nearly 50 years ago, less than two decades after the rise of commercial plastics production, when less than 50 million metric tons were produced per year. In 2014, global plastics production surpassed 300 million metric tons per year. Plastic debris has been detected worldwide in all major marine habitats, in sizes from microns to meters. In response, concerns about risks to marine wildlife upon exposure to the varied forms of plastic debris have increased, stimulating new research into the extent and consequences of plastics contamination in the marine environment. Here, I present a framework to evaluate the current understanding of the sources, distribution, fate, and impacts of marine plastics. Despite remaining knowledge gaps in mass budgeting and challenges in investigating ecological impacts, the increasing evidence of the ubiquity of plastics contamination in the marine environment, the continued rapid growth in plastics production, and the evidence—albeit limited—of demonstrated impacts to marine wildlife support immediate implementation of source-reducing measures to decrease the potential risks of plastics in the marine ecosystem.
Selection of polychlorinated plastics in plastic waste by X-ray fluorescence method

International Nuclear Information System (INIS)

Kumasaki, H.; Shinozaki, Y.

1979-01-01

The X-ray fluorescence method using a small source of 55 Fe was examined and found to be applicable for the selection of polychlorinated plastics from plastic waste in model areas in Tokyo designated for investigating their content in the waste. The weight ratios of soft and hard polychlorinated plastics to the total plastic waste estimated by this method were found to be 15.6% and 0.29% respectively. These values agree well with the results obtained with the Beilstein method. (author)
Toxicological Threats of Plastic

Science.gov (United States)

Plastics pose both physical (e.g., entanglement, gastrointestinal blockage, reef destruction) and chemical threats (e.g., bioaccumulation of the chemical ingredients of plastic or toxic chemicals sorbed to plastics) to wildlife and the marine ecosystem.
Antioxidant-Conjugated Onto Gamma-Generated Chitosan Nanoparticle for Radiation Sterilized Medical Plastic

Energy Technology Data Exchange (ETDEWEB)

Pasaphan, W. [Department of Applied Radiation and Isotopes, Faculty of Science Kasetsart University, Bangkok (Thailand)

2009-07-01

The Department of Applied Radiation and Isotopes, Faculty of Science, Kasetsart University, Bangkok, Thailand, mainly gives the course of study in the field of radiation and nuclear science and technology. The research actitivies relevant to the department are about nuclear instrument and analytical technique by nuclear methodology, radiation chemistry and processing technology, and radiation biology and agriculture. My work going on in the department is separated into two main responsibilities, i.e. (i) teaching courses and (ii) research activity. For (i), in the present time, there are 5 courses (i.e., radiation detection technique, radiation health protection, nuclear method of analysis, radioistope tracer techniques in biology and seminar) for bachelor degree and 4 courses (radiation chemistry and processing, radiation detection and dosimetry, nuclear facilities and utilization, research method in applied radiation and isotope) for master degree. In the case of (ii), my research interests head on the radiation chemistry and processing applicable to material and nanomaterial development for industrial applications, e.g. nanofilter and metal absorbent material; for medical applications, e.g. bio-additive for medical material, nanoparticle for drug delivery system, radiosensitizer for radiotherapy; for agricultural applications, e.g. pest controlled compound and plastic. The researches are also attended to biopolymer especially chitin-chiosan including functional polymer. The material for radiation dosimeter based on EPR is furthermore interesting to look for.

Antioxidant-Conjugated Onto Gamma-Generated Chitosan Nanoparticle for Radiation Sterilized Medical Plastic

International Nuclear Information System (INIS)

Pasaphan, W.

2009-01-01

The Department of Applied Radiation and Isotopes, Faculty of Science, Kasetsart University, Bangkok, Thailand, mainly gives the course of study in the field of radiation and nuclear science and technology. The research actitivies relevant to the department are about nuclear instrument and analytical technique by nuclear methodology, radiation chemistry and processing technology, and radiation biology and agriculture. My work going on in the department is separated into two main responsibilities, i.e. (i) teaching courses and (ii) research activity. For (i), in the present time, there are 5 courses (i.e., radiation detection technique, radiation health protection, nuclear method of analysis, radioistope tracer techniques in biology and seminar) for bachelor degree and 4 courses (radiation chemistry and processing, radiation detection and dosimetry, nuclear facilities and utilization, research method in applied radiation and isotope) for master degree. In the case of (ii), my research interests head on the radiation chemistry and processing applicable to material and nanomaterial development for industrial applications, e.g. nanofilter and metal absorbent material; for medical applications, e.g. bio-additive for medical material, nanoparticle for drug delivery system, radiosensitizer for radiotherapy; for agricultural applications, e.g. pest controlled compound and plastic. The researches are also attended to biopolymer especially chitin-chiosan including functional polymer. The material for radiation dosimeter based on EPR is furthermore interesting to look for
Current organic chemistry

National Research Council Canada - National Science Library

1997-01-01

Provides in depth reviews on current progress in the fields of asymmetric synthesis, organometallic chemistry, bioorganic chemistry, heterocyclic chemistry, natural product chemistry, and analytical...
Plasticity and beyond microstructures, crystal-plasticity and phase transitions

CERN Document Server

Hackl, Klaus

2014-01-01

The book presents the latest findings in experimental plasticity, crystal plasticity, phase transitions, advanced mathematical modeling of finite plasticity and multi-scale modeling. The associated algorithmic treatment is mainly based on finite element formulations for standard (local approach) as well as for non-standard (non-local approach) continua and for pure macroscopic as well as for directly coupled two-scale boundary value problems. Applications in the area of material design/processing are covered, ranging from grain boundary effects in polycrystals and phase transitions to deep-drawing of multiphase steels by directly taking into account random microstructures.
Vegetative and reproductive evaluation of hot peppers under different plastic mulches in poly/plastic tunnel

International Nuclear Information System (INIS)

Iqbal, Q.; Amjad, M.; Ahmad, R.

2009-01-01

Since the beginning of civilization, the man has developed technologies to increase the efficiency of food production. The use of plastic mulch in commercial vegetable production is one of these traditional techniques that have been used for centuries. Studies were conducted to assess the efficacy of plastic mulch on growth and yield of two hot pepper hybrids, viz. Sky Red and Maha in poly/plastic tunnel. The treatments were black plastic mulch, clear plastic mulch and bare soil as control. Both hot pepper hybrids mulched with black plastic showed significantly better vegetative growth (plant height, leaf area etc) and fruit yield. Clear plastic mulch significantly increased soil temperature and reduced the number of days to first flower than black plastic mulch and bare soil. However, fruit yield was higher by 39.56 and 36.49% respectively in both hybrids when they were grown on black and clear plastic mulch as compared to bare soil. Overall results indicated that the use of plastic mulch is an ideal option to maximize hot pepper productivity as well as to extend their production season in poly/plastic tunnels. (author)
Aquatic Chemistry

International Nuclear Information System (INIS)

Kim, Dong Yeun; Kim, Oh Sik; Kim, Chang Guk; Park, Cheong Gil; Lee, Gwi Hyeon; Lee, Cheol Hui

1987-07-01

This book deals aquatic chemistry, which treats water and environment, chemical kinetics, chemical balance like dynamical characteristic, and thermodynamics, acid-base chemistry such as summary, definition, kinetics, and PH design for mixture of acid-base chemistry, complex chemistry with definition, and kinetics, precipitation and dissolution on summary, kinetics of precipitation and dissolution, and balance design oxidation and resolution with summary, balance of oxidation and resolution.
Combinatorial chemistry

DEFF Research Database (Denmark)

Nielsen, John

1994-01-01

An overview of combinatorial chemistry is presented. Combinatorial chemistry, sometimes referred to as `irrational drug design,' involves the generation of molecular diversity. The resulting chemical library is then screened for biologically active compounds.......An overview of combinatorial chemistry is presented. Combinatorial chemistry, sometimes referred to as `irrational drug design,' involves the generation of molecular diversity. The resulting chemical library is then screened for biologically active compounds....
Forensic Chemistry

Science.gov (United States)

Bell, Suzanne

2009-07-01

Forensic chemistry is unique among chemical sciences in that its research, practice, and presentation must meet the needs of both the scientific and the legal communities. As such, forensic chemistry research is applied and derivative by nature and design, and it emphasizes metrology (the science of measurement) and validation. Forensic chemistry has moved away from its analytical roots and is incorporating a broader spectrum of chemical sciences. Existing forensic practices are being revisited as the purview of forensic chemistry extends outward from drug analysis and toxicology into such diverse areas as combustion chemistry, materials science, and pattern evidence.
Chemistry-nuclear chemistry division. Progress report, October 1979-September 1980

International Nuclear Information System (INIS)

Ryan, R.R.

1981-05-01

This report presents the research and development programs pursued by the Chemistry-Nuclear Chemistry Division of the Los Alamos National Laboratory. Topics covered include advanced analytical methods, atmospheric chemistry and transport, biochemistry, biomedical research, element migration and fixation, inorganic chemistry, isotope separation and analysis, atomic and molecular collisions, molecular spectroscopy, muonic x rays, nuclear cosmochemistry, nuclear structure and reactions, radiochemical separations, theoretical chemistry, and unclassified weapons research
Chemistry-nuclear chemistry division. Progress report, October 1979-September 1980

Energy Technology Data Exchange (ETDEWEB)

Ryan, R.R. (comp.)

1981-05-01

This report presents the research and development programs pursued by the Chemistry-Nuclear Chemistry Division of the Los Alamos National Laboratory. Topics covered include advanced analytical methods, atmospheric chemistry and transport, biochemistry, biomedical research, element migration and fixation, inorganic chemistry, isotope separation and analysis, atomic and molecular collisions, molecular spectroscopy, muonic x rays, nuclear cosmochemistry, nuclear structure and reactions, radiochemical separations, theoretical chemistry, and unclassified weapons research.
Interaction between vegetable oil based plasticizer molecules and polyvinyl chloride, and their plasticization effect

Science.gov (United States)

Haryono, Agus; Triwulandari, Evi; Jiang, Pingping

2017-01-01

Plasticizer molecules are low molecular weight compounds that are widely used in polymer industries especially in polyvinyl chloride (PVC) resin. As an additive in PVC resin, the important role of plasticizer molecules is to improve the flexibility and processability of PVC by lowering the glass transition temperature (Tg). However, the commercial plasticizer like di(2-ethylhexyl)phthalate (DEHP) is known to cause liver cancer, at least in laboratory rats. DEHP can leach out from PVC into blood, certain drug solutions and fatty foods, which has been detected in the bloodstream of patients undergoing transfusion. Vegetable oil based plasticizers have some attractive properties such as non-toxic, bio-degradable, good heat and light stability, renewable resources, and environmentally friendly. Here we discussed the main results and development of vegetable oil based plasticizer, and especially palm oil based plasticizer. The interaction between plasticizer and polymer was discussed from the properties of the plasticized polymeric material.
Outline of investigation on restraint of carbon dioxide generation by green chemistry. 1999.1-1999.3; 1998 nendo green chemistry ni yoru CO2 hassei yokusei ni kakawaru chosa kenkyu chosa hokokusho

Energy Technology Data Exchange (ETDEWEB)

NONE

1999-03-01

Investigations were conducted into the above in some leading OECD (Organization for Economic Cooperation and Development) member states. Green chemistry is a new concept in which clean technology, environment-friendly chemistry, and the like are combined, and is a chemical solution for reducing or stopping the use or generation of materials, products, by-products, solvents, reagents, etc., which are dangerous to health and environments, throughout the whole life cycle of chemicals covering the processes of their designing, manufacturing, dumping, and recycling. In this fiscal year, the actual state of the generation of biomass, regarded as representative of reproducible materials, and its feasibility as chemical resources were investigated. In an effort at finding out chemical reactions safer to health and causing less environmental impact, investigations were also conducted into the recent trends of catalysts, novel reactions for organic syntheses, use of supercritical fluids, photocatalysts, biomimetic processes, etc. The development of substitutes for plastic additives was also studied. Since acceptance by the citizenry is quite important for green chemistry to take effect, educating and enlightening activities in the U.S., Britain, France, and Germany were inquired into. (NEDO)
The Brazilian medicinal chemistry from 1998 to 2008 in the Journal of Medicinal Chemistry, Bioorganic and Medicinal Chemistry, Bioorganic and Medicinal Chemistry Letters and European Journal of Medicinal Chemistry [A química medicinal brasileira de 1998 a 2008 nos periódicos Journal of Medicinal Chemistry, Bioorganic and Medicinal Chemistry, Bioorganic and Medicinal Chemistry Letters e European Journal of Medicinal Chemistry

OpenAIRE

Bárbara Vasconcellos da Silva; Renato Saldanha Bastos; Angelo da Cunha Pinto

2009-01-01

In this article we present the Brazilian publications, the research groups involved, the contributions per states and the main diseases studied from 1998 to 2008 in the following periodicals: Journal of Medicinal Chemistry, Bioorganic and Medicinal Chemistry, Bioorganic and Medicinal Chemistry Letters and European Journal of Medicinal Chemistry.
Handbook of Plastic Welding

DEFF Research Database (Denmark)

Islam, Aminul

The purpose of this document is to summarize the information about the laser welding of plastic. Laser welding is a matured process nevertheless laser welding of micro dimensional plastic parts is still a big challenge. This report collects the latest information about the laser welding of plastic...... materials and provides an extensive knowhow on the industrial plastic welding process. The objectives of the report include: - Provide the general knowhow of laser welding for the beginners - Summarize the state-of-the-art information on the laser welding of plastics - Find the technological limits in terms...... of design, materials and process - Find the best technology, process and machines adaptive to Sonion’s components - Provide the skills to Sonion’s Design Engineers for successful design of the of the plastic components suitable for the laser welding The ultimate goal of this report is to serve...
Central African Journal of Medicine - Vol 60, No 9-12 (2016)

African Journals Online (AJOL)

Central African Journal of Medicine - Vol 60, No 9-12 (2016). Journal Home > Archives > Vol 60, No 9-12 (2016). Supplementary Issue. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue ...
Abiotic degradation of plastic films

Science.gov (United States)

Ángeles-López, Y. G.; Gutiérrez-Mayen, A. M.; Velasco-Pérez, M.; Beltrán-Villavicencio, M.; Vázquez-Morillas, A.; Cano-Blanco, M.

2017-01-01

Degradable plastics have been promoted as an option to mitigate the environmental impacts of plastic waste. However, there is no certainty about its degradability under different environmental conditions. The effect of accelerated weathering (AW), natural weathering (NW) and thermal oxidation (TO) on different plastics (high density polyethylene, HDPE; oxodegradable high density polyethylene, HDPE-oxo; compostable plastic, Ecovio ® metalized polypropylene, PP; and oxodegradable metalized polypropylene, PP-oxo) was studied. Plastics films were exposed to AW per 110 hours; to NW per 90 days; and to TO per 30 days. Plastic films exposed to AW and NW showed a general loss on mechanical properties. The highest reduction in elongation at break on AW occurred to HDPE-oxo (from 400.4% to 20.9%) and was higher than 90% for HDPE, HDPE-oxo, Ecovio ® and PP-oxo in NW. No substantial evidence of degradation was found on plastics exposed to TO. Oxo-plastics showed higher degradation rates than their conventional counterparts, and the compostable plastic was resistant to degradation in the studied abiotic conditions. This study shows that degradation of plastics in real life conditions will vary depending in both, their composition and the environment.
Plasticity characteristic obtained by indentation

International Nuclear Information System (INIS)

Mil'man, Yu.V.; Chugunova, S.I.; Goncharova, I.V.

2011-01-01

Methods for determination plasticity characteristic δH in the measurement of hardness and nanohardness are considered. Parameter δH characterizes the plasticity of a material by the part of plastic deformation in the total elastic-plastic deformation. The value of δH is defined for metals with different types of crystal lattice, covalent and partially covalent crystals, intermetallics, metallic glasses and quasicrystals. It is discussed the dependence of the plasticity characteristic δH on structural factors and temperature. Parameter δH allows to analyze and compare the plasticity of materials which are brittle at standard mechanical tests. The combination of hardness H, as the strength characteristic, and the plasticity characteristic δH makes possible the better characterization of mechanical behavior of materials than only the hardness H. The examples of plasticity characteristic δH application are represented.
Bad chemistry

OpenAIRE

Petsko, Gregory A

2004-01-01

General chemistry courses haven't changed significantly in forty years. Because most basic chemistry students are premedical students, medical schools have enormous influence and could help us start all over again to create undergraduate chemistry education that works.
Experiments with elasto-plastic oscillator

DEFF Research Database (Denmark)

Randrup-thomsen, Søren; Ditlevsen, Ove Dalager

1996-01-01

Plastic displacements of a Gaussian white noise excited three degrees of freedom non-ideal elasto-plastic oscillator are measured in laboratory experiments and the plastic displacements are compared to computer simulated results for the corresponding ideal elasto-plastic oscillator. The comparative...
Experiments with elasto-plastic oscillator

DEFF Research Database (Denmark)

Randrup-Thomsen, S.; Ditlevsen, Ove Dalager

1999-01-01

Plastic displacements of a Gaussian white noise excited three degrees of freedom non-ideal elasto-plastic oscillator are measured in laboratory experiments and the plastic displacements are compared to computer simulated results for the corresponding ideal elasto-plastic oscillator. The comparative...
Analysis of plastic residues in maple sap and syrup collected from tubing systems sanitized with isopropyl alcohol

Directory of Open Access Journals (Sweden)

Luc Lagacé

2017-05-01

Full Text Available A plastic tubing system operated under vacuum is usually used to collect sap from maple trees during spring time to produce maple syrup. This system is commonly sanitized with isopropyl alcohol (IPA to remove microbial contamination colonizing the system during the sugar season. Questions have been raised whether IPA would contribute to the leaching of plastic residues in maple sap and syrup coming from sanitized systems. First, an extraction experiment was performed in the lab on commercial plastic tubing materials that were submitted to IPA under harsh conditions. The results of the GC-MS analysis revealed the presence of many compounds that served has target for further tests. Secondly, tests were done on early and mid-season maple sap and syrup coming from many sugarbushes using IPA or not to determine potential concentrations of plastic residues. Results obtained from sap and syrup samples showed that no quantifiable (< 1–75 μg/L concentration of any plastic molecules tested was determined in all samples coming from IPA treated or not treated systems. However, some samples of first sap run used as a rinse solution to be discarded before the season start and that were coming from non sanitized or IPA sanitized systems, showed quantifiable concentrations of chemical residue such as ultraviolet protector (octabenzone. These results show that IPA can be safely used to sanitize maple sap collection system in regards to the leaching of plastic residues in maple sap and syrup and reinforced the need to thoroughly rinse the tubing system at the beginning of the season for both sanitized and non sanitized systems. Keywords: Food science, Food safety, Materials chemistry

ENVIRONMENTAL ISSUE-PLASTIC

OpenAIRE

Sunita Shakle

2017-01-01

Polythene is the most common plastic, the annual global production is approximately 60 million tones, and its primary use is in packing. Plastic bags pollute soil and waters and kill thousands of marine generalize plastic bags are not biodegradable they clog water ways, spoil the land scape and end up in landfills. Where they may take 1000 year or more to break down into ever smaller particals that continue to pollution the soil and water.
Positronium chemistry

CERN Document Server

Green, James

1964-01-01

Positronium Chemistry focuses on the methodologies, reactions, processes, and transformations involved in positronium chemistry. The publication first offers information on positrons and positronium and experimental methods, including mesonic atoms, angular correlation measurements, annihilation spectra, and statistical errors in delayed coincidence measurements. The text then ponders on positrons in gases and solids. The manuscript takes a look at the theoretical chemistry of positronium and positronium chemistry in gases. Topics include quenching, annihilation spectrum, delayed coincidence
Clinics in Mother and Child Health - Vol 5, No 1 (2008)

African Journals Online (AJOL)

Clinics in Mother and Child Health - Vol 5, No 1 (2008). Journal Home > Archives > Vol 5, No 1 (2008). Special Edition - Congress Abstracts. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue ...
Nano-Ceramic Coated Plastics

Science.gov (United States)

Cho, Junghyun

2013-01-01

Plastic products, due to their durability, safety, and low manufacturing cost, are now rapidly replacing cookware items traditionally made of glass and ceramics. Despite this trend, some still prefer relatively expensive and more fragile ceramic/glassware because plastics can deteriorate over time after exposure to foods, which can generate odors, bad appearance, and/or color change. Nano-ceramic coatings can eliminate these drawbacks while still retaining the advantages of the plastic, since the coating only alters the surface of the plastic. The surface coating adds functionality to the plastics such as self-cleaning and disinfectant capabilities that result from a photocatalytic effect of certain ceramic systems. These ceramic coatings can also provide non-stick surfaces and higher temperature capabilities for the base plastics without resorting to ceramic or glass materials. Titanium dioxide (TiO2) and zinc oxide (ZnO) are the candidates for a nano-ceramic coating to deposit on the plastics or plastic films used in cookware and kitchenware. Both are wide-bandgap semiconductors (3.0 to 3.2 eV for TiO2 and 3.2 to 3.3 eV for ZnO), so they exhibit a photocatalytic property under ultraviolet (UV) light. This will lead to decomposition of organic compounds. Decomposed products can be easily washed off by water, so the use of detergents will be minimal. High-crystalline film with large surface area for the reaction is essential to guarantee good photocatalytic performance of these oxides. Low-temperature processing (nano-ceramic coatings (TiO2, ZnO) on plastic materials (silicone, Teflon, PET, etc.) that can possess both photocatalytic oxide properties and flexible plastic properties. Processing cost is low and it does not require any expensive equipment investment. Processing can be scalable to current manufacturing infrastructure.
Proceedings of the second international conference on environmental impact assessment of all economical activities. Vol. 1

International Nuclear Information System (INIS)

1993-01-01

Proceedings of the conference consist of 3 volumes: Vol. 1 - 'Environmental Impact Assessment of all Economical Activities including Industry'; Vol. 2 - 'Air Pollution Control and Prevention'; Vol. 3 - Waste Management and Environmental Problems in Construction Industry'. Out of 32 papers contained in Vol. 1, 2 were inputted to INIS. They deal with models of radionuclide transport in food chains and the use of aerial monitoring in the study of environmental contamination. (Z.S.)
Non-thermally activated chemistry

International Nuclear Information System (INIS)

Stiller, W.

1987-01-01

The subject is covered under the following headings: state-of-the art of non-thermally activated chemical processes; basic phenomena in non-thermal chemistry including mechanochemistry, photochemistry, laser chemistry, electrochemistry, photo-electro chemistry, high-field chemistry, magneto chemistry, plasma chemistry, radiation chemistry, hot-atom chemistry, and positronium and muonium chemistry; elementary processes in non-thermal chemistry including nuclear chemistry, interactions of electromagnetic radiations, electrons and heavy particles with matter, ionic elementary processes, elementary processes with excited species, radicalic elementary processes, and energy-induced elementary processes on surfaces and interfaces; and comparative considerations. An appendix with historical data and a subject index is given. 44 figs., 41 tabs., and 544 refs
Elastic-plastic analysis of AS4/PEEK composite laminate using a one-parameter plasticity model

Science.gov (United States)

Sun, C. T.; Yoon, K. J.

1992-01-01

A one-parameter plasticity model was shown to adequately describe the plastic deformation of AS4/PEEK (APC-2) unidirectional thermoplastic composite. This model was verified further for unidirectional and laminated composite panels with and without a hole. The elastic-plastic stress-strain relations of coupon specimens were measured and compared with those predicted by the finite element analysis using the one-parameter plasticity model. The results show that the one-parameter plasticity model is suitable for the analysis of elastic-plastic deformation of AS4/PEEK composite laminates.
Performance of molded plastic scintillators

International Nuclear Information System (INIS)

Gen, N.S.; Leman, V.E.; Solomonov, V.M.

1989-01-01

The performance of molded plastic scintillators is studied. The plastic scintillators studied were formed by transfer molding and intrusion from a scintillation composition consisting of polystyrene and a standard system of luminescent additives: 2 mass % of paraterphenyl + 0.06 mass % 1,4-di-/2-[5-phenyloxazoyly]/benzene and a plasticizer. The combined effect of mechanical load and temperature was studied. The effect of radiation on molded plastic scintillators was studied using gamma radiation from a 60 Co source. The studies show that the main operating characteristics of molded plastic scintillators are on a par with those of polymerized plastic scintillators. At the same time, molded plastic scintillators are superior in thermal stability at temperatures below the glass transition temperature and with respect to their working temperature range
Plastic food packaging and health

Directory of Open Access Journals (Sweden)

Raika Durusoy

2011-02-01

Full Text Available Plastics have a wide usage in our daily lives. One of their uses is for food packaging and food containers. The aim of this review is to introduce different types of chemicals that can leach from food packaging plastics into foods and cause human exposure and to mention their effects on health. The types of plastics were reviewed under the 13 headings in Turkish Codex Alimentarius and plastics recycling symbols were provided to enable the recognition of the type of plastic when applicable. Chemicals used during the production and that can cause health risks are investigated under the heading of the relevant type of plastic. The most important chemicals from plastic food packaging that can cause toxicity are styrene, 1,3-butadiene, melamine, formaldehyde, acrylamide, di-2-ethylhexyl phthalate, di-2-ethylhexyl adipate, vinyl chloride and bisphenol A. These chemicals have endocrine disrupting, carcinogenic and/or development disrupting effects. These chemicals may leach into foods depending on the chemical properties of the plastic or food, temperature during packaging, processing and storage, exposure to UV and duration of storage. Contact with fatty/oily or acidic foods, heating of the food inside the container, or drinking hot drinks from plastic cups, use of old and scratched plastics and some detergents increase the risk of leaching. The use of plastic containers and packaging for food and beveradges should be avoided whenever possible and when necessary, less harmful types of plastic should be preferred. [TAF Prev Med Bull 2011; 10(1.000: 87-96
Radiotracers in medical applications, vols 1-2

International Nuclear Information System (INIS)

Rayudu, G.V.S.

1983-01-01

These volumes will serve as a basis for instruction and reference for professionals such as radiopharmaceutical chemists, radiopharmacologists, radiopharmacists, radiobiochemists, and others involved in the medical applications of radiotracers. Vol. I: Topics include radiohalogenated compounds, including radioiodine; Tc-labeled compounds; and in-house prepared radiopharmaceuticals. The charge particle range vs. energy in every element is tabulated for protons for cyclotrons users. Discussions are also provided on nonimaging radiotracer methods; 11 C, 13 N, 15 O, 67 Ga. 111 In, 75 Se, /SUP 123m/ Te compounds; radioactive noble gases; and miscellaneous radiotracers for imaging. Vol. II: Pertinent nuclear science data such as radiation dosimetry, radionuclide production modes, radionuclides for therapy, human experimentation regulations and consent forms, and radiotracer laboratory designs are presented
Z Physics at LEP 1. Vol. 3

International Nuclear Information System (INIS)

Altarelli, G.; Kleiss, R.; Verzegnassi, C.

1989-01-01

The contents of this final report from the Workshop on Z Physics at LEP can be divided into two parts. The first part, comprising Vols. 1 and 2, is a relatively concise but fairly complete handbook on the physics of e + e - annihilation near the Z peak (with normal LEP luminosity and unpolarized beams, appropriate for the first phase of LEP operation). The second part (Vol. 3) is devoted to a review of the existing Monte Carlo event generators for LEP physics. A special effort has been made to co-ordinate the different parts of this report, with the aim of achieving a systematic and balanced review of the subject, rather than having simply a collection of separate contributions. (orig.)
Z physics at LEP 1. Vol. 1

International Nuclear Information System (INIS)

Altarelli, G.; Kleiss, R.; Verzegnassi, C.

1989-01-01

The contents of this final report from the Workshop on Z Physics at LEP can be divided into two parts. The first part, comprising Vols. 1 and 2, is a relatively concise but fairly complete handbook on the physics of e + e - annihilation near the Z peak (with normal LEP luminosity and unpolarized beams, appropriate for the first phase of LEP operation). The second part (Vol. 3) is devoted to a review of the existing Monte Carlo event generators for LEP physics. A special effort has been made to co-ordinate the different parts of this report, with the aim of achieving a systematic and balanced review of the subject, rather than having simply a collection of separate contributions. (orig.)
Our plastic age

OpenAIRE

Thompson, Richard C.; Swan, Shanna H.; Moore, Charles J.; vom Saal, Frederick S.

2009-01-01

Within the last few decades, plastics have revolutionized our daily lives. Globally we use in excess of 260 million tonnes of plastic per annum, accounting for approximately 8 per cent of world oil production. In this Theme Issue of Philosophical Transactions of the Royal Society, we describe current and future trends in usage, together with the many benefits that plastics bring to society. At the same time, we examine the environmental consequences resulting from the accumulation of waste pl...
A Conservative Formulation for Plasticity

Science.gov (United States)

1992-01-01

concepts that apply to a broad class of macroscopic models: plastic deformation and plastic flow rule. CONSERVATIVE PLASTICITY 469 3a. Plastic Defrrnation...temperature. We illustrate these concepts with a model that has been used to describe high strain-rate plastic flow in metals [11, 31, 32]. In the case...JOURDREN, AND P. VEYSSEYRE. Un Modele ttyperelastique- Plastique Euldrien Applicable aux Grandes Dtformations: Que/ques R~sultats 1-D. preprint, 1991. 2. P
Green chemistry: A tool in Pharmaceutical Chemistry

OpenAIRE

Smita Talaviya; Falguni Majumdar

2012-01-01

Green chemistry expresses an area of research developing from scientific discoveries about pollution awareness and it utilizes a set of principles that reduces or eliminates the use or generation of hazardous substances in all steps of particular synthesis or process. Chemists and medicinal scientists can greatly reduce the risk to human health and the environment by following all the valuable principles of green chemistry. The most simple and direct way to apply green chemistry in pharmaceut...
Wood-plastic combination

International Nuclear Information System (INIS)

Schaudy, R.

1978-02-01

A review on wood-plastic combinations is given including the production (wood and plastic component, radiation hardening, curing), the obtained properties, present applications and prospects for the future of these materials. (author)
Plastic deformation and contact area of an elastic-plastic contact of ellipsoid bodies after unloading

NARCIS (Netherlands)

Jamari, Jamari; Schipper, Dirk J.

2007-01-01

This paper presents theoretical and experimental results of the residual or plastic deformation and the plastic contact area of an elastic–plastic contact of ellipsoid bodies after unloading. There are three regime responses of the deformation and contact area: elastic, elastic–plastic and fully
An ideal teaching program of nuclear chemistry in the undergraduate chemistry curriculum

International Nuclear Information System (INIS)

Uenak, T.

2009-01-01

It is well known that several reports on the common educational problems of nuclear chemistry have been prepared by certain groups of experts from time to time. According to very important statements in these reports, nuclear chemistry and related courses generally do not take sufficient importance in undergraduate chemistry curricula and it was generally proposed that nuclear chemistry and related courses should be introduced into undergraduate chemistry curricula at universities worldwide. Starting from these statements, an ideal program in an undergraduate chemistry curriculum was proposed to be introduced into the undergraduate chemistry program at the Department of Chemistry, Ege University, in Izmir, Turkey during the regular updating of the chemistry curriculum. Thus, it has been believed that this Department of Chemistry has recently gained an ideal teaching program in the field of nuclear chemistry and its applications in scientific, industrial, and medical sectors. In this contribution, the details of this program will be discussed. (author)
Processes in petroleum chemistry. Technical and economical characteristics Vol. 1. Synthesis gas and derivatives. Main hydrocarbon intermediaries (2 ed. )

Energy Technology Data Exchange (ETDEWEB)

Chauvel, A.; Lefebvre, G.; Castex, L.

1985-01-01

The aim of this book is to give rudiments for a preliminary study to outline petrochemical operation and cost estimation. Basic operations are examined: Steam reforming or partial oxidation, steam or thermal cracking and catalytic reforming. The main topics examined include: hydrogen purification, hydrogen fabrication from hydrocarbons, carbonaceous materials or water, production of carbon monoxide, ammoniac synthesis methanol synthesis from synthesis gas, preparation of formol, urea, acetylene and monomers for the preparation of plastics.
Proceedings of the 1. Arabic conference on chemical applications (Chemia 2). Vol. 2

International Nuclear Information System (INIS)

1997-11-01

The conference of chemical application was held on 1-5 Nov 1997 in Cairo, This vol.2 contains of chemical application on nuclear materials. Studies on these vol.This second volume covers papers presented on the subjects

BWR Water Chemistry Guidelines: 1993 Revision, Normal and hydrogen water chemistry

International Nuclear Information System (INIS)

Karlberg, G.; Goddard, C.; Fitzpatrick, S.

1994-02-01

The goal of water chemistry control is to extend the operating life of the reactor and rector coolant system, balance-of-plant components, and turbines while simultaneously controlling costs to safeguard the continued economic viability of the nuclear power generation investment. To further this goal an industry committee of chemistry personnel prepared guidelines to identify the benefits, risks, and costs associated with water chemistry in BWRs and to provide a template for an optimized water chemistry program. This document replaces the BWR Normal Water Chemistry Guidelines - 1986 Revision and the BWR Hydrogen Water Chemistry Guidelines -- 1987 Revision. It expands on the previous guidelines documents by covering the economic implications of BWR water chemistry control
Proceedings of the second international conference on environmental impact assessment of all economical activities. Vol. 2

International Nuclear Information System (INIS)

1993-01-01

Proceedings of the conference consist of 3 volumes: Vol. 1 - 'Environmental Impact Assessment of all Economical Activities including Industry'; Vol. 2 - 'Air Pollution Control and Prevention'; Vol. 3 - Waste Management and Environmental Problems in Construction Industry'. Out of 32 papers contained in Vol. 2, 4 were inputted to INIS. They deal with nuclear fusion as a potential energy source, with environmental aspects of disposal of ashes from power plants in the Czech Republic, and with land reclamation after mining activities. (Z.S.)
Chemistry-Nuclear Chemistry Division. Progress report, October 1980-September 1981

International Nuclear Information System (INIS)

Ryan, R.R.

1982-05-01

This report describes major progress in the research and development programs pursued by the Chemistry-Nuclear Chemistry Division of the Los Alamos National Laboratory during FY 1981. Topics covered include advanced analytical methods, atmospheric chemistry and transport, biochemistry, biomedical research, medical radioisotopes research, element migration and fixation, nuclear waste isolation research, inorganic and structural chemistry, isotope separation, analysis and applications, the newly established Nuclear Magnetic Resonance Center, atomic and molecular collisions, molecular spectroscopy, nuclear cosmochemistry, nuclear structure and reactions, pion charge exchange, radiochemical separations, theoretical chemistry, and unclassified weapons research
Chemistry-Nuclear Chemistry Division. Progress report, October 1980-September 1981

Energy Technology Data Exchange (ETDEWEB)

Ryan, R.R. (comp.)

1982-05-01

This report describes major progress in the research and development programs pursued by the Chemistry-Nuclear Chemistry Division of the Los Alamos National Laboratory during FY 1981. Topics covered include advanced analytical methods, atmospheric chemistry and transport, biochemistry, biomedical research, medical radioisotopes research, element migration and fixation, nuclear waste isolation research, inorganic and structural chemistry, isotope separation, analysis and applications, the newly established Nuclear Magnetic Resonance Center, atomic and molecular collisions, molecular spectroscopy, nuclear cosmochemistry, nuclear structure and reactions, pion charge exchange, radiochemical separations, theoretical chemistry, and unclassified weapons research.
Synaptic Plasticity and Nociception

Institute of Scientific and Technical Information of China (English)

ChenJianguo

2004-01-01

Synaptic plasticity is one of the fields that progresses rapidly and has a lot of success in neuroscience. The two major types of synaptie plasticity: long-term potentiation ( LTP and long-term depression (LTD are thought to be the cellular mochanisms of learning and memory. Recently, accumulating evidence suggests that, besides serving as a cellular model for learning and memory, the synaptic plasticity involves in other physiological or pathophysiological processes, such as the perception of pain and the regulation of cardiovascular system. This minireview will focus on the relationship between synaptic plasticity and nociception.
System Chemistry to Control Potential Environmental and Safety Hazards of Recycled Concrete Aggregate With Lead-Based Paint

Science.gov (United States)

2010-01-01

will usually buffer the TCLP test so it would not be classified as a hazardous waste. Acidification of soil does change the chemistry and mobility...crushed concrete product from around the stockpile at Fort Jackson (Figure 8). Each sample of a few kilograms was placed in a plastic “zip-lock...Jackson, rainfall quantity and pH for Columbia, SC first had to be determined. 5.2 Columbia rain data A review of data from National Oceanic and
Japan. Wood-Plastic Composites [Status and technology of polymer-containing fibrous materials in the Eastern Hemisphere

Energy Technology Data Exchange (ETDEWEB)

Hirayama, T. [Central Research Laboratory, Showa Denko K.K., Ota-Ku, Tokyo (Japan)

1968-10-15

Radiation chemistry research has made rapid progress in Japan over the last ten years, and many encouraging results have been obtained with radiation polymerization and graft-polymerization as well as in other fields. Several papers on wood-plastic composites (WPC) have been published in Japanese journals, but very little work on actual applications has been reported. This general review of basic studies and studies of the application of WPC in Japan is divided into three parts: radiation methods, chemical methods (catalyst-heat treatment) and the scope of future research and development.
Fundamentals of nuclear chemistry

International Nuclear Information System (INIS)

Majer, V.

1982-01-01

The author of the book has had 25 years of experience at the Nuclear Chemistry of Prague Technical University. In consequence, the book is intended as a basic textbook for students of this field. Its main objectives are an easily understandable presentation of the complex subject and in spite of the uncertainty which still characterizes the definition and subjects of nuclear chemistry - a systematic classification and logical structure. Contents: 1. Introduction (history and definition); 2. General nuclear chemistry (physical fundamentals, hot atom chemistry, interaction of nuclear radiation with matter, radioactive elements, isotope effects, isotope exchange, chemistry of radioactive trace elements); 3. Methods of nuclear chemistry of nuclear chemistry (radiochemical methods, activation, separation and enrichment chemistry); 4. Preparative nuclear chemistry (isotope production, labelled compounds); 5. Analytival nuclear chemistry; 6. Applied nuclear chemistry (isotope applications in general physical and analytical chemistry). The book is supplemented by an annex with tables, a name catalogue and a subject index which will facilitate access to important information. (RB) [de
Index to Nuclear Safety. A technical progress review by chronology, permuted title, and author. Vol 11, No. 1 through Vol. 16, No. 6

International Nuclear Information System (INIS)

Cottrell, W.B.; Klein, A.

1976-04-01

This index to Nuclear Safety covers articles in Nuclear Safety Vol. 11, No. 1 (Jan.-Feb. 1970) through Vol. 16, No. 6 (Nov.-Dec. 1975). Included in the index is a chronological list of articles (including abstract) followed by both a KWIC index and an Author Index. Nuclear Safety is a bimonthly technical progress review prepared by the Nuclear Safety Information Center and covers all safety aspects of nuclear power reactors and associated facilities. The index lists over 300 technical articles in the last six years of publication
Index to Nuclear Safety. A technical progress review by chronology, permuted title, and author. Vol 11, No. 1 through Vol. 16, No. 6

Energy Technology Data Exchange (ETDEWEB)

Cottrell, W.B.; Klein, A.

1976-04-01

This index to Nuclear Safety covers articles in Nuclear Safety Vol. 11, No. 1 (Jan.-Feb. 1970) through Vol. 16, No. 6 (Nov.-Dec. 1975). Included in the index is a chronological list of articles (including abstract) followed by both a KWIC index and an Author Index. Nuclear Safety is a bimonthly technical progress review prepared by the Nuclear Safety Information Center and covers all safety aspects of nuclear power reactors and associated facilities. The index lists over 300 technical articles in the last six years of publication.
Scientific Information Analysis of Chemistry Dissertations Using Thesaurus of Chemistry

Directory of Open Access Journals (Sweden)

Taghi Rajabi

2017-09-01

Full Text Available : Concept maps of chemistry can be obtained from thesaurus of chemistry. Analysis of information in the field of chemistry is done at graduate level, based on comparing and analyzing chemistry dissertations by using these maps. Therefore, the use of thesaurus for analyzing scientific information is recommended. Major advantage of using this method, is that it is possible to obtain a detailed map of all academic researches across all branches of science. The researches analysis results in chemical science can play a key role in developing strategic research policies, educational programming, linking universities to industries and postgraduate educational programming. This paper will first introduce the concept maps of chemistry. Then, emerging patterns from the concept maps of chemistry will be used to analyze the trend in the academic dissertations in chemistry, using the data collected and stored in our database at Iranian Research Institute for Information Science and Technology (IranDoc over the past 10 years (1998-2009.
Hot Chemistry Laboratory decommissioning activities at IPEN/CNEN-SP, Brazil

International Nuclear Information System (INIS)

Camilo, Ruth L.; Lainetti, Paulo E.O.

2009-01-01

IPEN's fuel cycle activities were accomplished in laboratory and pilot plant scale and most facilities were built in the 70-80 years. Nevertheless, radical changes of the Brazilian nuclear policy in the beginning of 90's determined the interruption of several fuel cycle activities and facilities shutdown. Since then, IPEN has faced the problem of the pilot plants decommissioning considering that there was no experience/expertise in this field at all. In spite of this, some laboratory and pilot plant decommissioning activities have been performed in IPEN in the last years, even without previous experience and training support. One of the first decommissioning activities accomplished in IPEN involved the Hot Chemistry Laboratory. This facility was built in the beginning of the 80's with the proposal of supporting research and development in the nuclear chemistry area. It was decided to settle a new laboratory in the place where the Hot Chemistry Laboratory was installed, being necessary its total releasing from the radioactive contamination point of view. The previous work in the laboratory involved the manipulation of samples of irradiated nuclear fuel, besides plutonium-239 and uranium-233 standard solutions. There were 5 glove-boxes in the facility but only 3 were used with radioactive material. The glove-boxes contained several devices and materials, besides the radioactive compounds, such as: electric and electronic equipment, metallic and plastic pieces, chemical reagents, liquid and solid radioactive wastes, etc. The laboratory's decommissioning process was divided in 12 steps. This paper describes the procedures, problems faced and results related to the Hot Chemistry Laboratory decommissioning operations and its reintegration as a new laboratory of the Chemical and Environmental Technology Center (CQMA) - IPEN-CNEN/SP. (author)
DNA functionalization by dynamic chemistry

Directory of Open Access Journals (Sweden)

Zeynep Kanlidere

2016-10-01

Full Text Available Dynamic combinatorial chemistry (DCC is an attractive method to efficiently generate libraries of molecules from simpler building blocks by reversible reactions under thermodynamic control. Here we focus on the chemical modification of DNA oligonucleotides with acyclic diol linkers and demonstrate their potential for the deoxyribonucleic acid functionalization and generation of libraries of reversibly interconverting building blocks. The syntheses of phosphoramidite building blocks derived from D-threoninol are presented in two variants with protected amino or thiol groups. The threoninol building blocks were successfully incorporated via automated solid-phase synthesis into 13mer oligonucleotides. The amino group containing phosphoramidite was used together with complementary single-strand DNA templates that influenced the Watson–Crick base-pairing equilibrium in the mixture with a set of aldehyde modified nucleobases. A significant fraction of all possible base-pair mismatches was obtained, whereas, the highest selectivity (over 80% was found for the guanine aldehyde templated by the complementary cytosine containing DNA. The elevated occurrence of mismatches can be explained by increased backbone plasticity derived from the linear threoninol building block as a cyclic deoxyribose analogue.
Synthesis of biodegradable plastic from tapioca with N-Isopropylacrylamid and chitosan using glycerol as plasticizer

Science.gov (United States)

Syaubari; Safwani, S.; Riza, M.

2018-04-01

One of natural polymers that can be used as raw material in the manufacture of biodegradable plastic is tapioca and chitosan. The addition of other compounds such as glycerol as plasticizer is to improve the characteristics of the plastic that already produced. N- Isopropylacrylamid (NIPAm) is an organic compound that can be synthesized into a polymer or polymer grafting which also biodegradable too. This research aims tostudy the synthesis of biodegradable plastics from tapioca with the addition of chitosan, NIPAm, poly(NIPAm) and analyze the characteristics of biodegradable plastics that already produced. This research was done in three stages, there are (1) polymerization NIPAm, (2) the grafting of chitosan-poly NIPAm and (3) the synthesis of biodegradable plastics from starch mixture with variation of addition chitosan, NIPAm, poly(NIPAm), chitosan-graft-poly(NIPAm) and also variations of glycerol as plasticizer. The results of this research is a thin sheet of plastic which is will get analyzed for the characteristics of functional groups, mechanical, morphological and its biodegradability. FTIR spectra showed the grafting process with the new group formation of CO single-bond at 850 cm-1. Plastic with the addition of NIPAm and 1 ml glycerol has the highest tensile strength value about 31.1 MPa. Plastic with poly(NIPAm) and 4 ml glycerol produces the highest elongation value about 153.72%. Plastic with Chitosan-graft-poly(NIPAm) with 1 ml glycerol has the longest biodegradation because of the small mass-loss for six weeks which is about 6.6%.
New perspectives in plastic biodegradation.

Science.gov (United States)

Sivan, Alex

2011-06-01

During the past 50 years new plastic materials, in various applications, have gradually replaced the traditional metal, wood, leather materials. Ironically, the most preferred property of plastics--durability--exerts also the major environmental threat. Recycling has practically failed to provide a safe solution for disposal of plastic waste (only 5% out of 1 trillion plastic bags, annually produced in the US alone, are being recycled). Since the most utilized plastic is polyethylene (PE; ca. 140 million tons/year), any reduction in the accumulation of PE waste alone would have a major impact on the overall reduction of the plastic waste in the environment. Since PE is considered to be practically inert, efforts were made to isolate unique microorganisms capable of utilizing synthetic polymers. Recent data showed that biodegradation of plastic waste with selected microbial strains became a viable solution. Copyright © 2011 Elsevier Ltd. All rights reserved.
Avalanches and plastic flow in crystal plasticity: an overview

Science.gov (United States)

Papanikolaou, Stefanos; Cui, Yinan; Ghoniem, Nasr

2018-01-01

Crystal plasticity is mediated through dislocations, which form knotted configurations in a complex energy landscape. Once they disentangle and move, they may also be impeded by permanent obstacles with finite energy barriers or frustrating long-range interactions. The outcome of such complexity is the emergence of dislocation avalanches as the basic mechanism of plastic flow in solids at the nanoscale. While the deformation behavior of bulk materials appears smooth, a predictive model should clearly be based upon the character of these dislocation avalanches and their associated strain bursts. We provide here a comprehensive overview of experimental observations, theoretical models and computational approaches that have been developed to unravel the multiple aspects of dislocation avalanche physics and the phenomena leading to strain bursts in crystal plasticity.
25th anniversary article: progress in chemistry and applications of functional indigos for organic electronics.

Science.gov (United States)

Głowacki, Eric Daniel; Voss, Gundula; Sariciftci, Niyazi Serdar

2013-12-17

Indigo and its derivatives are dyes and pigments with a long and distinguished history in organic chemistry. Recently, applications of this 'old' structure as a functional organic building block for organic electronics applications have renewed interest in these molecules and their remarkable chemical and physical properties. Natural-origin indigos have been processed in fully bio-compatible field effect transistors, operating with ambipolar mobilities up to 0.5 cm(2) /Vs and air-stability. The synthetic derivative isoindigo has emerged as one of the most successful building-blocks for semiconducting polymers for plastic solar cells with efficiencies > 5%. Another isomer of indigo, epindolidione, has also been shown to be one of the best reported organic transistor materials in terms of mobility (∼2 cm(2) /Vs) and stability. This progress report aims to review very recent applications of indigoids in organic electronics, but especially to logically bridge together the hereto independent research directions on indigo, isoindigo, and other materials inspired by historical dye chemistry: a field which was the root of the development of modern chemistry in the first place. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Melting the Plastic Ceiling: Overcoming Obstacles to Foster Leadership in Women Plastic Surgeons.

Science.gov (United States)

Silva, Amanda K; Preminger, Aviva; Slezak, Sheri; Phillips, Linda G; Johnson, Debra J

2016-09-01

The underrepresentation of women leaders in plastic surgery echoes a phenomenon throughout society. The importance of female leadership is presented, and barriers to gender equality in plastic surgery, both intrinsic and extrinsic, are discussed. Strategies for fostering women in leadership on an individual level and for the specialty of plastic surgery are presented.
Some Limitations in the Use of Plastic and Dyed Plastic Dosimeters

DEFF Research Database (Denmark)

Miller, Arne; Bjergbakke, Erling; McLaughlin, W. L.

1975-01-01

Several practical plastic and dyed plastic dosimeters were examined under irradiation conditions similar to those used for radiation processing of materials. Cellulose triacetate, polymethyl methacrylate, polyvinyl chloride, dyed polymethyl methacrylate, dyed Cellophane and dyed Nylon were given...
Exploration of fluorine chemistry at the multidisciplinary interface of chemistry and biology.

Science.gov (United States)

Ojima, Iwao

2013-07-05

Over the last three decades, my engagement in "fluorine chemistry" has evolved substantially because of the multidisciplinary nature of the research programs. I began my research career as a synthetic chemist in organometallic chemistry and homogeneous catalysis directed toward organic synthesis. Then, I was brought into a very unique world of "fluorine chemistry" in the end of 1970s. I started exploring the interface of fluorine chemistry and transition metal homogeneous catalysis first, which was followed by amino acids, peptides, and peptidomimetics for medicinal chemistry. Since then, I have been exploring the interfaces of fluorine chemistry and multidisciplinary fields of research involving medicinal chemistry, chemical biology, cancer biology, and molecular imaging. This perspective intends to cover my fruitful endeavor in the exploration of fluorine chemistry at the multidisciplinary interface of chemistry and biology in a chronological order to show the evolution of my research interest and strategy.

Nuclear chemistry

International Nuclear Information System (INIS)

Vertes, A.; Kiss, I.

1987-01-01

This book is an introduction to the application of nuclear science in modern chemistry. The first group of chapters discuss the basic phenomena and concepts of nuclear physics with emphasis on their relation to chemical problems, including the main properties and the composition of atomic nuclei, nuclear reactions, radioactive decay and interactions of radiation with matter. These chapters provide the basis for understanding the following chapters which encompass the wide scope of nuclear chemistry. The methods of the investigation of chemical structure based on the interaction of nuclear radiation with matter including positronium chemistry and other exotic atoms is elaborated in particular detail. Separate chapters are devoted to the use of radioactive tracers, the chemical consequences of nuclear processes (i.e. hot atom chemistry), radiation chemistry, isotope effects and their applications, and the operation of nuclear reactors
Nuclear chemistry

International Nuclear Information System (INIS)

Vertes, A.; Kiss, I.

1987-01-01

This book is an introduction to the application of nuclear science in modern chemistry. The first group of chapters discuss the basic phenomena and concepts of nuclear physics with emphasis on their relation to chemical problems, including the main properties and the composition of atomic nuclei, nuclear reactions, radioactive decay and interactions of radiation with matter. These chapters provide the basis for understanding the following chapters which encompass the wide scope of nuclear chemistry. The methods of the investigation of chemical structure based on the interaction of nuclear radiation with matter including positronium chemistry and other exotic atoms is elaborated in particular detail. Separate chapters are devoted to the use of radioactive tracers, the chemical consequences of nuclear processes (i.e. hot atom chemistry), radiation chemistry, isotope effects and their applications, and the operation of nuclear reactors. (Auth.)
Plastic Fishes

CERN Multimedia

Trettnak, Wolfgang

2015-01-01

In terms of weight, the plastic pollution in the world’s oceans is estimated to be around 300,000 tonnes. This plastic comes from both land-based and ocean-based sources. A lecture at CERN by chemist Wolfgang Trettnak addressed this issue and highlighted the role of art in raising people’s awareness. The slideshow below gives you a taste of the artworks by Wolfgang Trettnak and Margarita Cimadevila.
Plasticity resembling spike-timing dependent synaptic plasticity: the evidence in human cortex

Directory of Open Access Journals (Sweden)

Florian Müller-Dahlhaus

2010-07-01

Full Text Available Spike-timing dependent plasticity (STDP has been studied extensively in a variety of animal models during the past decade but whether it can be studied at the systems level of the human cortex has been a matter of debate. Only recently newly developed non-invasive brain stimulation techniques such as transcranial magnetic stimulation (TMS have made it possible to induce and assess timing dependent plasticity in conscious human subjects. This review will present a critical synopsis of these experiments, which suggest that several of the principal characteristics and molecular mechanisms of TMS-induced plasticity correspond to those of STDP as studied at a cellular level. TMS combined with a second phasic stimulation modality can induce bidirectional long-lasting changes in the excitability of the stimulated cortex, whose polarity depends on the order of the associated stimulus-evoked events within a critical time window of tens of milliseconds. Pharmacological evidence suggests an NMDA receptor mediated form of synaptic plasticity. Studies in human motor cortex demonstrated that motor learning significantly modulates TMS-induced timing dependent plasticity, and, conversely, may be modulated bidirectionally by prior TMS-induced plasticity, providing circumstantial evidence that long-term potentiation-like mechanisms may be involved in motor learning. In summary, convergent evidence is being accumulated for the contention that it is now possible to induce STDP-like changes in the intact human central nervous system by means of TMS to study and interfere with synaptic plasticity in neural circuits in the context of behaviour such as learning and memory.
Analytical Chemistry as Methodology in Modern Pure and Applied Chemistry

OpenAIRE

Honjo, Takaharu

2001-01-01

Analytical chemistry is an indispensable methodology in pure and applied chemistry, which is often compared to a foundation stone of architecture. In the home page of jsac, it is said that analytical chemistry is a learning of basic science, which treats the development of method in order to get usefull chemical information of materials by means of detection, separation, and characterization. Analytical chemistry has recently developed into analytical sciences, which treats not only analysis ...
Fundamentals of nuclear chemistry

International Nuclear Information System (INIS)

Majer, K.

1982-01-01

The textbook is a Czech-to-German translation of the second revised edition and covers the subject under the headings: general nuclear chemistry, methods of nuclear chemistry, preparative nuclear chemistry, analytical nuclear chemistry, and applied chemistry. The book is especially directed to students
HMI Department of Radiation Chemistry: Results of scientific activities in 1984

International Nuclear Information System (INIS)

1985-01-01

In the radiation chemistry department of the Hahn-Meitner-Institute in Berlin, 4 subjects are treated largely the progress of which made in 1984 is herein reported: 1) Interface processes and energy conversion (reaction pathways of photoinduced charge carriers and their in energy conversion mechanisms); 2) Pulse radiolysis (generation and investigation of shortlived chemically quick-reacting particles); 3) Kinematics (reciprocal action with ion, atom and molecule collisions; clarification of the dynamics of chemical reactions; 4) Insulators and plastics/physical and chemical primary processes when these materials are subjected to high-energy radiation, light or UV light). A list of publications and lectures is added to complement the description of results gained from R and D work. (BR) [de
Student Scientific Conference, 2008. Collection of contributions. Vol. 2 - Sections of geography, geology, environment, chemistry and didactics; Studentska vedecka konferencia, 2008

Energy Technology Data Exchange (ETDEWEB)

NONE

2008-04-15

The conference included the following sections: (i) Biology (114 contributions); (ii) Geography (37 contributions); (iii) Geology (24 contributions); (iv) Environment (16 contributions); (v) Chemistry (11 contributions); (vi) Didactics (8 contributions). Contributions relevant to INIS interest have been inputted to INIS.
Surface chemistry essentials

CERN Document Server

Birdi, K S

2013-01-01

Surface chemistry plays an important role in everyday life, as the basis for many phenomena as well as technological applications. Common examples range from soap bubbles, foam, and raindrops to cosmetics, paint, adhesives, and pharmaceuticals. Additional areas that rely on surface chemistry include modern nanotechnology, medical diagnostics, and drug delivery. There is extensive literature on this subject, but most chemistry books only devote one or two chapters to it. Surface Chemistry Essentials fills a need for a reference that brings together the fundamental aspects of surface chemistry w
Plastic and Non-plastic Debris Ingestion in Three Gull Species Feeding in an Urban Landfill Environment.

Science.gov (United States)

Seif, S; Provencher, J F; Avery-Gomm, S; Daoust, P-Y; Mallory, M L; Smith, P A

2018-04-01

Plastic debris is recognized as a widespread, common and problematic environmental pollutant. An important consequence of this pollution is the ingestion of plastic debris by wildlife. Assessing the degree to which different species ingest plastics, and the potential effects of these plastics on their health are important research needs for understanding the impacts of plastic pollution. We examined debris (plastic and other types) ingestion in three sympatric overwintering gull species (Herring gulls Larus smithsonianus, Great Black-backed Gulls Larus marinus, and Iceland Gulls Larus glaucoides) to understand how debris ingestion differs among species, age classes and sexes in gulls. We also assessed how plastic burdens were associated with body condition to investigate how gulls may be affected by debris ingestion. There were no differences among the species, age classes or sexes in the incidence of debris ingestion (plastic or otherwise), the mass or number of debris pieces ingested. We found no correlation between ingested plastics burdens and individual condition. Gulls ingested plastic debris, but also showed high levels of other debris types as well, including metal, glass and building materials, including a metal piece of debris found within an abscess in the stomach. Thus, when the health effects of debris ingestion on gulls, and other species that ingest debris, is of interest, either from a physical or chemical perspective, it may be necessary to consider all debris types and not just plastic burdens as is often currently done for seabirds.
Education on the Business of Plastic Surgery During Training: A Survey of Plastic Surgery Residents.

Science.gov (United States)

Ovadia, Steven A; Gishen, Kriya; Desai, Urmen; Garcia, Alejandro M; Thaller, Seth R

2018-06-01

Entrepreneurial skills are important for physicians, especially plastic surgeons. Nevertheless, these skills are not typically emphasized during residency training. Evaluate the extent of business training at plastic surgery residency programs as well as means of enhancing business training. A 6-question online survey was sent to plastic surgery program directors for distribution to plastic surgery residents. Responses from residents at the PGY2 level and above were included for analysis. Tables were prepared to present survey results. Hundred and sixty-six residents including 147 PGY2 and above residents responded to our survey. Only 43.5% reported inclusion of business training in their plastic surgery residency. A majority of residents reported they do not expect on graduation to be prepared for the business aspects of plastic surgery. Additionally, a majority of residents feel establishment of a formal lecture series on the business of plastic surgery would be beneficial. Results from our survey indicate limited training at plastic surgery programs in necessary business skills. Plastic surgery residency programs should consider incorporating or enhancing elements of business training in their curriculum. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .
The effects of plastic waves on the numerical convergence of the viscous-plastic and elastic-viscous-plastic sea-ice models

Science.gov (United States)

Williams, James; Tremblay, L. Bruno; Lemieux, Jean-François

2017-07-01

The plastic wave speed is derived from the linearized 1-D version of the widely used viscous-plastic (VP) and elastic-viscous-plastic (EVP) sea-ice models. Courant-Friedrichs-Lewy (CFL) conditions are derived using the propagation speed of the wave. 1-D numerical experiments of the VP, EVP and EVP* models successfully recreate a reference solution when the CFL conditions are satisfied, in agreement with the theory presented. The IMplicit-EXplicit (IMEX) method is shown to effectively alleviate the plastic wave CFL constraint on the timestep in the implicitly solved VP model in both 1-D and 2-D. In 2-D, the EVP and EVP* models show first order error in the simulated velocity field when the plastic wave is not resolved. EVP simulations are performed with various advective timestep, number of subcycles, and elastic-wave damping timescales. It is found that increasing the number of subcycles beyond that needed to resolve the elastic wave does not improve the quality of the solution. It is found that reducing the elastic wave damping timescale reduces the spatial extent of first order errors cause by the unresolved plastic wave. Reducing the advective timestep so that the plastic wave is resolved also reduces the velocity error in terms of magnitude and spatial extent. However, the parameter set required for convergence to within the error bars of satellite (RGPS) deformation fields is impractical for use in climate model simulations. The behavior of the EVP* method is analogous to that of the EVP method except that it is not possible to reduce the damping timescale with α = β.
The New Color of Chemistry: Green Chemistry

Directory of Open Access Journals (Sweden)

Zuhal GERÇEK

2012-01-01

Full Text Available Green chemistry which is the new application of chemistry rules provides solutions to problems that mankind is faced with climate changes, sustainable agriculture, energy, toxics, depletion of natural sources e.g. designing new chemicals and processes that production and utilization of hazardous matters. So, it is the indispensible tool for sustainable development. Current and future chemists should consider the human health and ecological issues in their professional life. In order to provide a solution for this requirement, green chemistry rules and under standings should be primarily taken in the university curriculum and at all educational levels.
Coliquefaction of coal, tar sand bitumen and plastic (interaction among coal, bitumen and plastic); Sekitan/tar sand bitumen/plastic no kyoekika ni okeru kyozon busshitsu no eikyo

Energy Technology Data Exchange (ETDEWEB)

Yamaguchi, H.; Okuyama, Y.; Matsubara, K. [NKK Corp., Tokyo (Japan); Kamo, T.; Sato, Y. [National Institute for Resources and Environment, Tsukuba (Japan)

1996-10-28

For the improvement of economy, coliquefaction of coal, tar sand bitumen and plastic was performed under low hydrogen pressure, to investigate the influence of interaction among these on the liquefaction characteristics. For comparison, coliquefaction was also performed under the hydrogen pressure same as the NEDOL process. In addition, for clarifying its reaction mechanism, coliquefaction of dibenzyl and plastic was performed as a model experiment, to illustrate the distribution of products and composition of oil, and to discuss the interaction between dibenzyl and various plastics, and between various plastics. Under direct coal liquefaction conditions, coprocessing of Tanito Harum coal, Athabasca tar sand and plastic was carried out under low hydrogen pressure with an autoclave. The observed value of oil yield was higher than the calculated value based on the values from separate liquefaction of coal and plastic, which suggested the interaction between coal and the mixed plastic. The results of coliquefaction of coal, tar sand bitumen and plastic could be explained from the obtained oil yield and its composition by the coliquefaction of dibenzyl and plastic. 2 refs., 3 tabs.
Technetium chemistry

International Nuclear Information System (INIS)

Burns, C.; Bryan, J.; Cotton, F.; Ott, K.; Kubas, G.; Haefner, S.; Barrera, J.; Hall, K.; Burrell, A.

1996-01-01

Technetium chemistry is a young and developing field. Despite the limited knowledge of its chemistry, technetium is the workhorse for nuclear medicine. Technetium is also a significant environmental concern because it is formed as a byproduct of nuclear weapons production and fission-power generators. Development of new technetium radio-pharmaceuticals and effective environmental control depends strongly upon knowledge of basic technetium chemistry. The authors performed research into the basic coordination and organometallic chemistry of technetium and used this knowledge to address nuclear medicine and environmental applications. This is the final report of a three-year Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL)
Correlación entre la microestructura y el comportamiento plástico a alta temperatura de compuestos TZP-Ni (40% vol.

Directory of Open Access Journals (Sweden)

Morales-Rodríguez, A.

2005-10-01

Full Text Available Microstructure and high-temperature mechanical behaviour of TZP-Ni composites with 40 vol.% of nickel above the percolation threshold (placed in 34 vol.% in these wet‑processed ceramic-metal composites has been studied. The microstructure has been characterized using scanning electron microscopy. The composite plasticity has been studied by means of uniaxial compressive creep tests under constant load in argon atmosphere carried out in the temperature range between 900 and 1250 ºC and stresses between 9 and 144 MPa. TZP skeleton has been deformed in similar conditions to study nickel effect in global cermet behavior. The metallic phase has been removed from the cermets using chemical etching with HNO3. The plastic behavior of these materials is controlled by the ceramic matrix. The deformation rates are higher than monolithic TZP ones. This fact has been explained taking into account the metallic phase distribution into the matrix in these composites. Metal percolation provides materials with high ductility allowing the cermets to deform at temperatures as low as 900 ºC.

Se ha estudiado la microestructura y el comportamiento mecánico a alta temperatura de compuestos de circona tetragonal (3Y-TZP con un 40% en volumen de níquel (referidos en adelante como TZP-Ni. El contenido en níquel está por encima del punto de percolación, que en estos compuestos cerámico-metal procesados en vía húmeda se sitúa en el 34% vol. de contenido metálico. La caracterización microestructural se ha realizado mediante observaciones de microscopía electrónica de barrido. La plasticidad de los compuestos se ha estudiado mediante ensayos de fluencia en compresión uniaxial a carga constante en atmósfera de argón realizados en el rango de temperaturas entre 900 y 1250 ºC y tensiones entre 9 y 144 MPa. Para estudiar el efecto del níquel en el comportamiento del cermet se ensayaron en condiciones similares esqueletos de TZP, obtenidos mediante la
Chemistry of Technetium

International Nuclear Information System (INIS)

Omori, Takashi

2001-01-01

Since the late 1970's the coordination chemistry of technetium has been developed remarkably. The background of the development is obviously related to the use of technetium radiopharmaceuticals for diagnosis in nuclear medicine. Much attention has also been denoted to the chemical behavior of environmental 99 Tc released from reprocessing plants. This review covers the several aspects of technetium chemistry, including production of radioisotopes, analytical chemistry and coordination chemistry. In the analytical chemistry, separation of technetium, emphasizing chromatography and solvent extraction, is described together with spectrophotometric determination of technetium. In the coordination chemistry of technetium, a characteristic feature of the chemistry of Tc(V) complexes is referred from the view point of the formation of a wide variety of highly stable complexes containing the Tc=O or Tc≡N bond. Kinetic studies of the preparation of Tc(III) complexes using hexakis (thiourea) technetium(III) ion as a starting material are summarized, together with the base hydrolysis reactions of Tc(III), Tc(IV) and Tc(V) complexes. (author)
A review of plastic waste biodegradation.

Science.gov (United States)

Zheng, Ying; Yanful, Ernest K; Bassi, Amarjeet S

2005-01-01

With more and more plastics being employed in human lives and increasing pressure being placed on capacities available for plastic waste disposal, the need for biodegradable plastics and biodegradation of plastic wastes has assumed increasing importance in the last few years. This review looks at the technological advancement made in the development of more easily biodegradable plastics and the biodegradation of conventional plastics by microorganisms. Additives, such as pro-oxidants and starch, are applied in synthetic materials to modify and make plastics biodegradable. Recent research has shown that thermoplastics derived from polyolefins, traditionally considered resistant to biodegradation in ambient environment, are biodegraded following photo-degradation and chemical degradation. Thermoset plastics, such as aliphatic polyester and polyester polyurethane, are easily attacked by microorganisms directly because of the potential hydrolytic cleavage of ester or urethane bonds in their structures. Some microorganisms have been isolated to utilize polyurethane as a sole source of carbon and nitrogen source. Aliphatic-aromatic copolyesters have active commercial applications because of their good mechanical properties and biodegradability. Reviewing published and ongoing studies on plastic biodegradation, this paper attempts to make conclusions on potentially viable methods to reduce impacts of plastic waste on the environment.
Proceedings of the second international conference on environmental impact assessment of all economical activities. Vol. 3

International Nuclear Information System (INIS)

1993-01-01

Proceedings of the conference consist of 3 volumes: Vol. 1 - 'Environmental Impact Assessment of all Economical Activities including Industry'; Vol. 2 - 'Air Pollution Control and Prevention'; Vol. 3 - Waste Management and Environmental Problems in Construction Industry'. Out of 39 papers contained in Vol. 3, 3 were inputted to INIS. They deal with the use of portable radioisotope X-ray fluorescence analyzers in the determination of building material contamination by toxic elements, with underground waste repositories and ground water contamination, and the impact of the Temelin nuclear power plant on the hydrosphere and other environmental components. (Z.S.)
Recycling of plastics

Energy Technology Data Exchange (ETDEWEB)

Kaminsky, W; Menzel, J; Sinn, H

1976-01-01

Considering the shortage of raw materials and environmental pollution, the recycling of plastic waste is a very important topic. Pilot plants for research in Funabashi Japan, Franklin (Ohio) U.S.A., and the R 80-process of Krauss Maffei, W. Germany, have demonstrated the possibility of reclaiming plastics from refuse. Old tires and waste from the plastic producing and manufacturing industries are readily available. The pyrolysis of plastic yields gaseous and liquid products, and the exploitation of this cracking reaction has been demonstrated by pilot plants in Japan and Great Britain. Further laboratory scale experiments are taking place in W. Germany. In continuous fluidized beds and in molten salts, polyethylene, polypropylene, polyvinylchloride, polystyrene and rubber are pyrolysed and better than 98 percent conversion is obtained. Up to 40 percent of the feed can be obtained as aromatic compounds, and a pilot plant is under construction. As a first step PVC-containing material can be almost quantitatively dehydrochlorinated.

Plastics and environment

International Nuclear Information System (INIS)

Avenas, P.

1996-01-01

Synthetic organic polymers, such as plastics, PVC, polyamides etc are considered less ecological than natural materials such as wood. Other artificial materials such as metals, glass or biodegradable plastics have also a better image than petroleum products. This short paper demonstrates that the manufacturing or the transport of every material uses energy and that the complete energy balance sheet of a plastic bottle, for instance, is more favourable than the one of a glass bottle. Plastic materials are also easily valorized and recycled and part of the energy spent during manufacturing can be recovered during incineration for district heating. During the life-cycle of such a synthetic material, the same petroleum quantity can be used twice which leads to less negative effects on the environment. Finally, the paper focusses on the problem of biodegradable materials which are not degradable when buried under several meters of wastes and which are a nuisance to recycling. (J.S.)
Stem cell plasticity.

Science.gov (United States)

Lakshmipathy, Uma; Verfaillie, Catherine

2005-01-01

The central dogma in stem cell biology has been that cells isolated from a particular tissue can renew and differentiate into lineages of the tissue it resides in. Several studies have challenged this idea by demonstrating that tissue specific cell have considerable plasticity and can cross-lineage restriction boundary and give rise to cell types of other lineages. However, the lack of a clear definition for plasticity has led to confusion with several reports failing to demonstrate that a single cell can indeed differentiate into multiple lineages at significant levels. Further, differences between results obtained in different labs has cast doubt on some results and several studies still await independent confirmation. In this review, we critically evaluate studies that report stem cell plasticity using three rigid criteria to define stem cell plasticity; differentiation of a single cell into multiple cell lineages, functionality of differentiated cells in vitro and in vivo, robust and persistent engraft of transplanted cells.
AJESMS_ Vol 8 2010 August 15 2011

African Journals Online (AJOL)

Prof. Mereku

2010-08-15

Aug 15, 2010 ... African Journal of Educational Studies in Mathematics and Sciences Vol. 8, 2010 ... environs, a mining area in Wassa West District of Ghana .... This finding is based on autopsy data and on reports showing that blood levels in.
Water SA - Vol 30, No 3 (2004)

African Journals Online (AJOL)

Application of a residential end-use model for estimating cold and hot water demand ... of multistage filtration using different filter media against conventional water ... (Germs et al., 2004), published in the April 2004 (Vol 30 No 2) issue of Water ...
Cross-Linked Amylose Bio-Plastic: A Transgenic-Based Compostable Plastic Alternative

Directory of Open Access Journals (Sweden)

Domenico Sagnelli

2017-09-01

Full Text Available Bio-plastics and bio-materials are composed of natural or biomass derived polymers, offering solutions to solve immediate environmental issues. Polysaccharide-based bio-plastics represent important alternatives to conventional plastic because of their intrinsic biodegradable nature. Amylose-only (AO, an engineered barley starch with 99% amylose, was tested to produce cross-linked all-natural bioplastic using normal barley starch as a control. Glycerol was used as plasticizer and citrate cross-linking was used to improve the mechanical properties of cross-linked AO starch extrudates. Extrusion converted the control starch from A-type to Vh- and B-type crystals, showing a complete melting of the starch crystals in the raw starch granules. The cross-linked AO and control starch specimens displayed an additional wide-angle diffraction reflection. Phospholipids complexed with Vh-type single helices constituted an integrated part of the AO starch specimens. Gas permeability tests of selected starch-based prototypes demonstrated properties comparable to that of commercial Mater-Bi© plastic. The cross-linked AO prototypes had composting characteristics not different from the control, indicating that the modified starch behaves the same as normal starch. The data shows the feasibility of producing all-natural bioplastic using designer starch as raw material.
Cross-Linked Amylose Bio-Plastic: A Transgenic-Based Compostable Plastic Alternative

Science.gov (United States)

Sagnelli, Domenico; Kemmer, Gerdi Christine; Holse, Mette; Hebelstrup, Kim H.; Bao, Jinsong; Stelte, Wolfgang; Bjerre, Anne-Belinda; Blennow, Andreas

2017-01-01

Bio-plastics and bio-materials are composed of natural or biomass derived polymers, offering solutions to solve immediate environmental issues. Polysaccharide-based bio-plastics represent important alternatives to conventional plastic because of their intrinsic biodegradable nature. Amylose-only (AO), an engineered barley starch with 99% amylose, was tested to produce cross-linked all-natural bioplastic using normal barley starch as a control. Glycerol was used as plasticizer and citrate cross-linking was used to improve the mechanical properties of cross-linked AO starch extrudates. Extrusion converted the control starch from A-type to Vh- and B-type crystals, showing a complete melting of the starch crystals in the raw starch granules. The cross-linked AO and control starch specimens displayed an additional wide-angle diffraction reflection. Phospholipids complexed with Vh-type single helices constituted an integrated part of the AO starch specimens. Gas permeability tests of selected starch-based prototypes demonstrated properties comparable to that of commercial Mater-Bi© plastic. The cross-linked AO prototypes had composting characteristics not different from the control, indicating that the modified starch behaves the same as normal starch. The data shows the feasibility of producing all-natural bioplastic using designer starch as raw material. PMID:28973963
Cross-Linked Amylose Bio-Plastic: A Transgenic-Based Compostable Plastic Alternative.

Science.gov (United States)

Sagnelli, Domenico; Hooshmand, Kourosh; Kemmer, Gerdi Christine; Kirkensgaard, Jacob J K; Mortensen, Kell; Giosafatto, Concetta Valeria L; Holse, Mette; Hebelstrup, Kim H; Bao, Jinsong; Stelte, Wolfgang; Bjerre, Anne-Belinda; Blennow, Andreas

2017-09-30

Bio-plastics and bio-materials are composed of natural or biomass derived polymers, offering solutions to solve immediate environmental issues. Polysaccharide-based bio-plastics represent important alternatives to conventional plastic because of their intrinsic biodegradable nature. Amylose-only (AO), an engineered barley starch with 99% amylose, was tested to produce cross-linked all-natural bioplastic using normal barley starch as a control. Glycerol was used as plasticizer and citrate cross-linking was used to improve the mechanical properties of cross-linked AO starch extrudates. Extrusion converted the control starch from A-type to Vh- and B-type crystals, showing a complete melting of the starch crystals in the raw starch granules. The cross-linked AO and control starch specimens displayed an additional wide-angle diffraction reflection. Phospholipids complexed with Vh-type single helices constituted an integrated part of the AO starch specimens. Gas permeability tests of selected starch-based prototypes demonstrated properties comparable to that of commercial Mater-Bi © plastic. The cross-linked AO prototypes had composting characteristics not different from the control, indicating that the modified starch behaves the same as normal starch. The data shows the feasibility of producing all-natural bioplastic using designer starch as raw material.
Physical Chemistry '98: Fourth International Conference on Fundamental and Applied Aspects of Physical Chemistry - Papers

International Nuclear Information System (INIS)

Ribnikar, S.; Anic, S.

1998-01-01

The proceedings has following chapters: Plenary lectures; Chemical Thermodynamics; Spectroscopy, Molecular Structures, Physical Chemistry of Plasma; Kinetics, Catalysis, Nonlinear Dynamics; Electrochemistry; Biophysical Chemistry, Photochemistry, Radiation Chemistry; Radiochemistry, Nuclear Chemistry; Solid State Physical Chemistry, Material Science; Macromolecular Physical Chemistry; Environmental Protection; Phase Boundaries; Complex Compounds; General Physical Chemistry. A separated abstract was prepared for each of the 20 papers selected from the three chapters: Biophysical Chemistry, Photochemistry, Radiation Chemistry; Radiochemistry, Nuclear Chemistry. and Environmental Protection. Refs and figs
Polymer-Derived Boron Nitride: A Review on the Chemistry, Shaping and Ceramic Conversion of Borazine Derivatives.

Science.gov (United States)

Bernard, Samuel; Miele, Philippe

2014-11-21

Boron nitride (BN) is a III-V compound which is the focus of important research since its discovery in the early 19th century. BN is electronic to carbon and thus, in the same way that carbon exists as graphite, BN exists in the hexagonal phase. The latter offers an unusual combination of properties that cannot be found in any other ceramics. However, these properties closely depend on the synthesis processes. This review states the recent developments in the preparation of BN through the chemistry, shaping and ceramic conversion of borazine derivatives. This concept denoted as Polymer-Derived Ceramics (PDCs) route allows tailoring the chemistry of precursors to elaborate complex BN shapes which cannot be obtained by conventional process. The effect of the chemistry of the molecular precursors, i.e. , borazine and trichloroborazine, and their polymeric derivatives i.e. , polyborazylene and poly[tri(methylamino)borazine], in which the specific functional groups and structural motifs determine the shaping potential by conventional liquid-phase process and plastic-forming techniques is discussed. Nanotubes, nano-fibers, coatings, monoliths and fiber-reinforced matrix composites are especially described. This leads to materials which are of significant engineering interest.
Polymer-Derived Boron Nitride: A Review on the Chemistry, Shaping and Ceramic Conversion of Borazine Derivatives

Directory of Open Access Journals (Sweden)

Samuel Bernard

2014-11-01

Full Text Available Boron nitride (BN is a III-V compound which is the focus of important research since its discovery in the early 19th century. BN is electronic to carbon and thus, in the same way that carbon exists as graphite, BN exists in the hexagonal phase. The latter offers an unusual combination of properties that cannot be found in any other ceramics. However, these properties closely depend on the synthesis processes. This review states the recent developments in the preparation of BN through the chemistry, shaping and ceramic conversion of borazine derivatives. This concept denoted as Polymer-Derived Ceramics (PDCs route allows tailoring the chemistry of precursors to elaborate complex BN shapes which cannot be obtained by conventional process. The effect of the chemistry of the molecular precursors, i.e., borazine and trichloroborazine, and their polymeric derivatives i.e., polyborazylene and poly[tri(methylaminoborazine], in which the specific functional groups and structural motifs determine the shaping potential by conventional liquid-phase process and plastic-forming techniques is discussed. Nanotubes, nano-fibers, coatings, monoliths and fiber-reinforced matrix composites are especially described. This leads to materials which are of significant engineering interest.
Plastics and beaches: A degrading relationship

International Nuclear Information System (INIS)

Corcoran, Patricia L.; Biesinger, Mark C.; Grifi, Meriem

2009-01-01

Plastic debris in Earth's oceans presents a serious environmental issue because breakdown by chemical weathering and mechanical erosion is minimal at sea. Following deposition on beaches, plastic materials are exposed to UV radiation and physical processes controlled by wind, current, wave and tide action. Plastic particles from Kauai's beaches were sampled to determine relationships between composition, surface textures, and plastics degradation. SEM images indicated that beach plastics feature both mechanically eroded and chemically weathered surface textures. Granular oxidation textures were concentrated along mechanically weakened fractures and along the margins of the more rounded plastic particles. Particles with oxidation textures also produced the most intense peaks in the lower wavenumber region of FTIR spectra. The textural results suggest that plastic debris is particularly conducive to both chemical and mechanical breakdown in beach environments, which cannot be said for plastics in other natural settings on Earth
Art and Plastic Surgery.

Science.gov (United States)

Fernandes, Julio Wilson; Metka, Susanne

2016-04-01

The roots of science and art of plastic surgery are very antique. Anatomy, drawing, painting, and sculpting have been very important to the surgery and medicine development over the centuries. Artistic skills besides shape, volume, and lines perception can be a practical aid to the plastic surgeons' daily work. An overview about the interactions between art and plastic surgery is presented, with a few applications to rhinoplasty, cleft lip, and other reconstructive plastic surgeries. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.
Radiation chemistry

Energy Technology Data Exchange (ETDEWEB)

None

1973-07-01

Research progress is reported on radiation chemistry of heavy elements that includes the following topics: radiation chemistry of plutonium in nitric acid solutions (spectrophotometric analysis and gamma radiolysis of Pu(IV) and Pu(VI) in nitric acid solution); EPR studies of intermediates formed in radiolytic reactions with aqueous medium; two-phase radiolysis and its effect on the distribution coefficient of plutonium; and radiation chemistry of nitric acid. (DHM)
Environmental chemistry. Seventh edition

Energy Technology Data Exchange (ETDEWEB)

Manahan, S.E. [Univ. of Missouri, Columbia, MO (United States)

1999-11-01

This book presents a basic understanding of environmental chemistry and its applications. In addition to providing updated materials in this field, the book emphasizes the major concepts essential to the practice of environmental chemistry. Topics of discussion include the following: toxicological chemistry; toxicological chemistry of chemical substances; chemical analysis of water and wastewater; chemical analysis of wastes and solids; air and gas analysis; chemical analysis of biological materials and xenobiotics; fundamentals of chemistry; and fundamentals of organic chemistry.
Plastics recycling: challenges and opportunities.

Science.gov (United States)

Hopewell, Jefferson; Dvorak, Robert; Kosior, Edward

2009-07-27

Plastics are inexpensive, lightweight and durable materials, which can readily be moulded into a variety of products that find use in a wide range of applications. As a consequence, the production of plastics has increased markedly over the last 60 years. However, current levels of their usage and disposal generate several environmental problems. Around 4 per cent of world oil and gas production, a non-renewable resource, is used as feedstock for plastics and a further 3-4% is expended to provide energy for their manufacture. A major portion of plastic produced each year is used to make disposable items of packaging or other short-lived products that are discarded within a year of manufacture. These two observations alone indicate that our current use of plastics is not sustainable. In addition, because of the durability of the polymers involved, substantial quantities of discarded end-of-life plastics are accumulating as debris in landfills and in natural habitats worldwide. Recycling is one of the most important actions currently available to reduce these impacts and represents one of the most dynamic areas in the plastics industry today. Recycling provides opportunities to reduce oil usage, carbon dioxide emissions and the quantities of waste requiring disposal. Here, we briefly set recycling into context against other waste-reduction strategies, namely reduction in material use through downgauging or product reuse, the use of alternative biodegradable materials and energy recovery as fuel. While plastics have been recycled since the 1970s, the quantities that are recycled vary geographically, according to plastic type and application. Recycling of packaging materials has seen rapid expansion over the last decades in a number of countries. Advances in technologies and systems for the collection, sorting and reprocessing of recyclable plastics are creating new opportunities for recycling, and with the combined actions of the public, industry and governments it
Plastics recycling: challenges and opportunities

Science.gov (United States)

Hopewell, Jefferson; Dvorak, Robert; Kosior, Edward

2009-01-01

Plastics are inexpensive, lightweight and durable materials, which can readily be moulded into a variety of products that find use in a wide range of applications. As a consequence, the production of plastics has increased markedly over the last 60 years. However, current levels of their usage and disposal generate several environmental problems. Around 4 per cent of world oil and gas production, a non-renewable resource, is used as feedstock for plastics and a further 3–4% is expended to provide energy for their manufacture. A major portion of plastic produced each year is used to make disposable items of packaging or other short-lived products that are discarded within a year of manufacture. These two observations alone indicate that our current use of plastics is not sustainable. In addition, because of the durability of the polymers involved, substantial quantities of discarded end-of-life plastics are accumulating as debris in landfills and in natural habitats worldwide. Recycling is one of the most important actions currently available to reduce these impacts and represents one of the most dynamic areas in the plastics industry today. Recycling provides opportunities to reduce oil usage, carbon dioxide emissions and the quantities of waste requiring disposal. Here, we briefly set recycling into context against other waste-reduction strategies, namely reduction in material use through downgauging or product reuse, the use of alternative biodegradable materials and energy recovery as fuel. While plastics have been recycled since the 1970s, the quantities that are recycled vary geographically, according to plastic type and application. Recycling of packaging materials has seen rapid expansion over the last decades in a number of countries. Advances in technologies and systems for the collection, sorting and reprocessing of recyclable plastics are creating new opportunities for recycling, and with the combined actions of the public, industry and governments it
Plastic pollutants in water environment

OpenAIRE

Mrowiec Bożena

2017-01-01

Nowadays, wide applications of plastics result in plastic waste being present in the water environment in a wide variety of sizes. Plastic wastes are in water mainly as microplastics (the size range of 1 nm to < 5 mm). Microplastics have been recognized as an emerging threat, as well as ecotoxicological and ecological risk for water ecosystems. In this review are presented some of the physicochemical properties of plastic materials that determine their toxic effect on the aquatic environment....
DEVELOPMENT OF PLASTIC SURGERY.

Science.gov (United States)

Pećanac, Marija Đ

2015-01-01

Plastic surgery is a medical specialty dealing with corrections of defects, improvements in appearance and restoration of lost function. Ancient times. The first recorded account of reconstructive plastic surgery was found in ancient Indian Sanskrit texts, which described reconstructive surgeries of the nose and ears. In ancient Greece and Rome, many medicine men performed simple plastic cosmetic surgeries to repair damaged parts of the body caused by war mutilation, punishment or humiliation. In the Middle Ages, the development of all medical braches, including plastic surgery was hindered. New age. The interest in surgical reconstruction of mutilated body parts was renewed in the XVIII century by a great number of enthusiastic and charismatic surgeons, who mastered surgical disciplines and became true artists that created new forms. Modern era. In the XX century, plastic surgery developed as a modern branch in medicine including many types of reconstructive surgery, hand, head and neck surgery, microsurgery and replantation, treatment of burns and their sequelae, and esthetic surgery. Contemporary and future plastic surgery will continue to evolve and improve with regenerative medicine and tissue engineering resulting in a lot of benefits to be gained by patients in reconstruction after body trauma, oncology amputation, and for congenital disfigurement and dysfunction.
Antiparallel Dynamic Covalent Chemistries.

Science.gov (United States)

Matysiak, Bartosz M; Nowak, Piotr; Cvrtila, Ivica; Pappas, Charalampos G; Liu, Bin; Komáromy, Dávid; Otto, Sijbren

2017-05-17

The ability to design reaction networks with high, but addressable complexity is a necessary prerequisite to make advanced functional chemical systems. Dynamic combinatorial chemistry has proven to be a useful tool in achieving complexity, however with some limitations in controlling it. Herein we introduce the concept of antiparallel chemistries, in which the same functional group can be channeled into one of two reversible chemistries depending on a controllable parameter. Such systems allow both for achieving complexity, by combinatorial chemistry, and addressing it, by switching from one chemistry to another by controlling an external parameter. In our design the two antiparallel chemistries are thiol-disulfide exchange and thio-Michael addition, sharing the thiol as the common building block. By means of oxidation and reduction the system can be reversibly switched from predominantly thio-Michael chemistry to predominantly disulfide chemistry, as well as to any intermediate state. Both chemistries operate in water, at room temperature, and at mildly basic pH, which makes them a suitable platform for further development of systems chemistry.
ECONOMICS OF ALEXANDER THE GREAT (15 vols + 4 cdroms) by Gregory Zorzos

OpenAIRE

Gregory Zorzos

2002-01-01

Research contains many ancient texts (Ancient Greek, Hebrews, Hieroglyphs, Assyrian, Sumerian, Babylonian, Latin, etc.). 1. (MICRO-MACRO ECONOMICS OF ALEXANDER THE GREAT (5 vols + cdrom). Microeconomics and macroeconomics of Alexander the Great. Economic theories, feasibilities, economic plannings, general description of the campaign's business plan etc. 2. BANKS OF ALEXANDER THE GREAT (2 vols + cdrom) Describes banking system, economists, financiers, investors, accountants, bookkeepers, etc,...

A work criterion for plastic collapse

International Nuclear Information System (INIS)

Muscat, Martin; Mackenzie, Donald; Hamilton, Robert

2003-01-01

A new criterion for evaluating limit and plastic loads in pressure vessel design by analysis is presented. The proposed criterion is based on the plastic work dissipated in the structure as loading progresses and may be used for structures subject to a single load or a combination of multiple loads. Example analyses show that limit and plastic loads given by the plastic work criterion are robust and consistent. The limit and plastic loads are determined purely by the inelastic response of the structure and are not influenced by the initial elastic response: a problem with some established plastic criteria
A Coupled Plastic Damage Model for Concrete considering the Effect of Damage on Plastic Flow

OpenAIRE

Zhou, Feng; Cheng, Guangxu

2015-01-01

A coupled plastic damage model with two damage scalars is proposed to describe the nonlinear features of concrete. The constitutive formulations are developed by assuming that damage can be represented effectively in the material compliance tensor. Damage evolution law and plastic damage coupling are described using the framework of irreversible thermodynamics. The plasticity part is developed without using the effective stress concept. A plastic yield function based on the true stress is ado...
More Chemistry with Light! More Light in Chemistry!

Science.gov (United States)

Bach, Thorsten

2015-09-21

"…︁ Why is chemistry overlooked when talking about light? Is the photon a physical particle per se? Are all important light-induced processes biological? Maybe the role of light for chemistry and the role of chemistry for light may be far less important than a few eccentric scientists would like to believe. From the perspective of a synthetically oriented photochemist, however, the facts are different …︁" Read more in the Editorial by Thorsten Bach. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Browse Title Index

African Journals Online (AJOL)

Items 151 - 200 of 463 ... Vol 2, No 2 (2010), Effect of magnetic field on the blood flow in artery ... Vol 3, No 2 (2011), Effect of normal stress under an excitation in poroelastic flat .... simulation of carbon manganese steel for cyclic plastic behaviour, Abstract PDF ... Vol 2, No 8 (2010), Fabrication of iron-cerium mixed oxide: an ...
Medicinal Chemistry/Pharmacology in Sophomore Organic Chemistry.

Science.gov (United States)

Harrison, Aline M.

1989-01-01

Discussed is a series of lectures designed to illustrate the use of general organic chemical principles in molecular biology, introduce current research in interdisciplinary areas to the beginner, increase interest in organic chemistry, and bridge the gap between traditional organic chemistry, biology, and the consumer. An outline is presented.…
Plastic solid waste utilization technologies: A Review

Science.gov (United States)

Awasthi, Arun Kumar; Shivashankar, Murugesh; Majumder, Suman

2017-11-01

Plastics are used in more number of applications in worldwide and it becomes essential part of our daily life. In Indian cities and villages people use the plastics in buying vegetable as a carry bag, drinking water bottle, use of plastic furniture in home, plastics objects uses in kitchen, plastic drums in packing and storage of the different chemicals for industrial use, use plastic utensils in home and many more uses. After usage of plastics it will become part of waste garbage and create pollution due to presence of toxic chemicals and it will be spread diseases and give birth to uncontrolled issues in social society. In current scenario consumption of plastic waste increasing day by day and it is very difficult to manage the plastic waste. There are limited methodologies available for reutilization of plastic waste again. Such examples are recycling, landfill, incineration, gasification and hydrogenation. In this paper we will review the existing methodologies of utilization of plastic waste in current scenario
Plastic Pollution from Ships

OpenAIRE

Čulin, Jelena; Bielić, Toni

2016-01-01

The environmental impact of shipping on marine environment includes discharge of garbage. Plastic litter is of particular concern due to abundance, resistance to degradation and detrimental effect on marine biota. According to recently published studies, a further research is required to assess human health risk. Monitoring data indicate that despite banning plastic disposal at sea, shipping is still a source of plastic pollution. Some of the measures to combat the problem are discussed.
Power plant cycle chemistry - a currently neglected power plant chemistry discipline

International Nuclear Information System (INIS)

Bursik, A.

2005-01-01

Power plant cycle chemistry seems to be a stepchild at both utilities and universities and research organizations. It is felt that other power plant chemistry disciplines are more important. The last International Power Cycle Chemistry Conference in Prague may be cited as an example. A critical review of the papers presented at this conference seems to confirm the above-mentioned statements. This situation is very unsatisfactory and has led to an increasing number of component failures and instances of damage to major cycle components. Optimization of cycle chemistry in fossil power plants undoubtedly results in clear benefits and savings with respect to operating costs. It should be kept in mind that many seemingly important chemistry-related issues lose their importance during forced outages of units practicing faulty plant cycle chemistry. (orig.)
Practical solution of plastic deformation problems in elastic-plastic range

Science.gov (United States)

Mendelson, A; Manson, S

1957-01-01

A practical method for solving plastic deformation problems in the elastic-plastic range is presented. The method is one of successive approximations and is illustrated by four examples which include a flat plate with temperature distribution across the width, a thin shell with axial temperature distribution, a solid cylinder with radial temperature distribution, and a rotating disk with radial temperature distribution.
Chemistry

International Nuclear Information System (INIS)

Ferris, L.M.

1975-01-01

The chemical research and development efforts related to the design and ultimate operation of molten-salt breeder reactor systems are concentrated on fuel- and coolant-salt chemistry, including the development of analytical methods for use in these systems. The chemistry of tellurium in fuel salt is being studied to help elucidate the role of this element in the intergranular cracking of Hastelloy N. Studies were continued of the effect of oxygen-containing species on the equilibrium between dissolved UF 3 and dissolved UF 4 , and, in some cases, between the dissolved uranium fluorides and graphite, and the UC 2 . Several aspects of coolant-salt chemistry are under investigation. Hydroxy and oxy compounds that could be formed in molten NaBF 4 are being synthesized and characterized. Studies of the chemistry of chromium (III) compounds in fluoroborate melts were continued as part of a systematic investigation of the corrosion of structural alloys by coolant salt. An in-line voltammetric method for determining U 4+ /U 3+ ratios in fuel salt was tested in a forced-convection loop over a six-month period. (LK)
From trace chemistry to single atom chemistry

International Nuclear Information System (INIS)

Adloff, J.P.

1993-01-01

Hot atom chemistry in the vast majority of experimental works deals with the trace amount of radioactive matters. Accordingly, the concept of trace chemistry is at the heart of hot atom chemistry. Some aspects of the chemistry at trace scale and at subtrace scale are presented together with the related problems of speciation and the complication which may arise due to the formation of radio colloids. The examples of 127 I(n,γ) 128 I and 132 Te (β - ) 132 I are shown, and the method based on radioactivity was used. The procedure of separating the elements in pitchblende is shown as the example of the chemistry of traces. 13 27 Al+ 2 4 He→ 0 1 n+ 15 30 P and 15 30 P→ 14 30 Si+e + +V are shown, and how to recognize the presence of radioactive colloids is explained. The formation of radiocolloids is by the sorption of a trace radioelement on pre-existing colloidal impurity or the self-condensation of monomeric species. The temporal parameters of the nature of reactions at trace concentration are listed. The examples of Class A and Class B reactions are shown. The kinetics of reactions at trace level, radon concentration, anthropogenic Pu and natural Pu in environment, the behavior of Pu atoms and so on are described. (K.I.)
Organic chemistry

International Nuclear Information System (INIS)

2003-08-01

This book with sixteen chapter explains organic chemistry on linkage isomerism such as alkane, cycloalkane, alkene, aromatic compounds, stereo selective isomerization, aromatic compounds, stereo selective isomerization, organic compounds, stereo selective isomerization, organic halogen compound, alcohol, ether, aldehyde and ketone, carboxylic acid, dicarboxylic acid, fat and detergent, amino, carbohydrate, amino acid and protein, nucleotide and nucleic acid and spectroscopy, a polymer and medical chemistry. Each chapter has introduction structure and characteristic and using of organic chemistry.
Preparative radiation chemistry

International Nuclear Information System (INIS)

Drawe, H.

1978-01-01

Preparative synthesis of compounds with the aid of radiation chemistry is increasingly used in laboratories as well as on a technical scale. A large number of new compounds has been produced with the methods of radiation chemistry. With the increasing number of available radiation sources, also the number of synthesis metods in radiation chemistry has increased. This paper can only briefly mention the many possible ways of synthesis in radiation chemistry. (orig./HK) [de
Extruding plastic scintillator at Fermilab

International Nuclear Information System (INIS)

Pla-Dalmau, Anna; Bross, Alain D.; Rykalin, Viktor V.

2003-01-01

An understanding of the costs involved in the production of plastic scintillators and the development of a less expensive material have become necessary with the prospects of building very large plastic scintillation detectors. Several factors contribute to the high cost of plastic scintillating sheets, but the principal reason is the labor-intensive nature of the manufacturing process. In order to significantly lower the costs, the current casting procedures had to be abandoned. Since polystyrene is widely used in the consumer industry, the logical path was to investigate the extrusion of commercial-grade polystyrene pellets with dopants to yield high quality plastic scintillator. This concept was tested and high quality extruded plastic scintillator was produced. The D0 and MINOS experiments are already using extruded scintillator strips in their detectors. An extrusion line has recently been installed at Fermilab in collaboration with NICADD (Northern Illinois Center for Accelerator and Detector Development). This new facility will serve to further develop and improve extruded plastic scintillator. This paper will discuss the characteristics of extruded plastic scintillator and its raw materials, the different manufacturing techniques and the current R andD program at Fermilab
Applications and societal benefits of plastics.

Science.gov (United States)

Andrady, Anthony L; Neal, Mike A

2009-07-27

This article explains the history, from 1600 BC to 2008, of materials that are today termed 'plastics'. It includes production volumes and current consumption patterns of five main commodity plastics: polypropylene, polyethylene, polyvinyl chloride, polystyrene and polyethylene terephthalate. The use of additives to modify the properties of these plastics and any associated safety, in use, issues for the resulting polymeric materials are described. A comparison is made with the thermal and barrier properties of other materials to demonstrate the versatility of plastics. Societal benefits for health, safety, energy saving and material conservation are described, and the particular advantages of plastics in society are outlined. Concerns relating to littering and trends in recycling of plastics are also described. Finally, we give predictions for some of the potential applications of plastic over the next 20 years.
Plastic pollutants in water environment

Directory of Open Access Journals (Sweden)

Mrowiec Bożena

2017-12-01

Full Text Available Nowadays, wide applications of plastics result in plastic waste being present in the water environment in a wide variety of sizes. Plastic wastes are in water mainly as microplastics (the size range of 1 nm to < 5 mm. Microplastics have been recognized as an emerging threat, as well as ecotoxicological and ecological risk for water ecosystems. In this review are presented some of the physicochemical properties of plastic materials that determine their toxic effect on the aquatic environment. Wastewater treatment plants (WWTPs are mentioned as one of main sources of microplastics introduced into fresh water, and rivers are the pathways for the transportation of the pollutants to seas and oceans. But, effluents from tertiary wastewater treatment facilities can contain only minimally microplastic loads. The issue of discharge reduction of plastic pollutants into water environment needs activities in the scope of efficient wastewater treatment, waste disposal, recycling of plastic materials, education and public involvement.
Track treeing mechanism and plastic zone in solid Part 1: Initial development of plastic zone

International Nuclear Information System (INIS)

Li Boyang

2008-01-01

After neutron exposure and chemical etching in advance, latent tracks of recoil nucleon develop into pits on CR39 surface. During electrochemical etching, plastic zone is formed at top of pits. Some pits develop into tree cracks in the initial stage of plastic zone development. Physical and mathematical model of crack and plastic zone is proposed; parameter of development free path of plastic zone is presented. Based on integration of elementary theories the stress analysis is build up; based on analyses of measured parameters, a set of common relations between parameters is obtained. Integrate parameter analysis and stress analysis, depth of plastic zone development, law and phenomenon in experimental data can be interpreted completely
Gender and Behaviour - Vol 5, No 2 (2007)

African Journals Online (AJOL)

Gender and Behaviour. ... Gender and Behaviour - Vol 5, No 2 (2007) ... Home Type, Age and Gender on The Antisocial Behaviour of Secondary School Students. ... Gender-Wise Comparison on Emotional Intelligence and Marital Satisfaction.
Afican Health Sciences Vol 10 No 4.pmd

African Journals Online (AJOL)

Administrator

African Health Sciences Vol 10 No 4 December 2010. 353. Effect of ... Key words: Rumex steudelii, Antifertility, Folliculogenesis, Endometrium, uterus, ovary, ovarian follicles, corpus luteum,. Rats. ..... first cycle in intrauterine growth-related and.
Accumulation of plastic-derived chemicals in tissues of seabirds ingesting marine plastics.

Science.gov (United States)

Tanaka, Kosuke; Takada, Hideshige; Yamashita, Rei; Mizukawa, Kaoruko; Fukuwaka, Masa-aki; Watanuki, Yutaka

2013-04-15

We analyzed polybrominated diphenyl ethers (PBDEs) in abdominal adipose of oceanic seabirds (short-tailed shearwaters, Puffinus tenuirostris) collected in northern North Pacific Ocean. In 3 of 12 birds, we detected higher-brominated congeners (viz., BDE209 and BDE183), which are not present in the natural prey (pelagic fish) of the birds. The same compounds were present in plastic found in the stomachs of the 3 birds. These data suggested the transfer of plastic-derived chemicals from ingested plastics to the tissues of marine-based organisms. Copyright © 2012 Elsevier Ltd. All rights reserved.

Organic chemistry experiment

International Nuclear Information System (INIS)

Mun, Seok Sik

2005-02-01

This book deals with organic chemistry experiments, it is divided five chapters, which have introduction, the way to write the experiment report and safety in the laboratory, basic experiment technic like recrystallization and extraction, a lot of organic chemistry experiments such as fischer esterification, ester hydrolysis, electrophilic aromatic substitution, aldol reaction, benzoin condensation, wittig reaction grignard reaction, epoxidation reaction and selective reduction. The last chapter introduces chemistry site on the internet and way to find out reference on chemistry.
Preliminary evaluation of rotational Vol-oxidizer for hot cell operation - 5320

International Nuclear Information System (INIS)

Kim, Y.H.; Lee, J.W.; Cho, Y.Z.; Ahn, D.H.; Song, K.C.

2015-01-01

KAERI is developing a mechanical head-end process for pyro-processing. As a piece of the processing equipment, a vol-oxidizer that can handle several tens of kg of HM/batch is under development to supply U 3 O 8 powders to an electrolytic reduction (ER) reactor. To operate a vol-oxidizer in a hot cell, the reactor should be optimized by the mechanical design, and the vol-oxidizer should have a high hull recovery rate. In addition, a vol-oxidizer for hot cell demonstrations that handles the spent fuel of high radiation virulence in a limited space should have a small size and not scatter in its outlet. In this paper, we aim at a preliminary evaluation of a rotational vol-oxidizer for hot cell operation. To evaluate the preliminary situation, we produced a theoretical equation of an optimum reactor size, and verification tests were conducted using an acryl vessel and zircaloy-4 tube according to various weights and lengths. In addition, we predicted the terminal velocity of U 3 O 8 using the terminal velocity of SiO 2 , which will determine the optimum air flux, and through an oxidation experiment, we verified the theory form to detect the existence of U 3 O 8 powder in a discharge filter. In addition, hull separation tests were conducted using a reactor and hulls with a 50 kg HM/batch for the recovery rate of the hulls. The results indicate that we obtained an appropriate air flux so as to not cause U 3 O 8 powder dispersion from using a Stokes equation and density ratio equation prior to the demonstration. The optimum flow and experimental results of the hull separation test have been applied for the design of the demonstration oxidizer, and the operation conditions of the oxidizer were produced. (authors)
Joyo progress report, vol. 8

International Nuclear Information System (INIS)

1983-01-01

Following Joyo Reactor Technology Progress Reports (Vol. 1 to Vol. 7), the name was changed to Joyo Progress Report from this volume, and the activities concerning the fast breeder experimental reactor Joyo as a whole are to be reported as quarterly report. In the fast breeder experimental reactor Joyo, the change to the core for irradiation (MK-2) from the core for breeding (MK-1) was carried out since January, 1982, in order to utilize the reactor as an irradiation facility for the development of fuel and materials. The main work was the construction of the core for irradiation by exchanging 290 fuel elements, and the exchange of upper and lower guide pipes for control rods, the reconstruction of the driving mechanism, the installation of standby neutron detector system, the acceptance and inspection of new fuel, and the transfer of spent fuel between pools were carried out. As scheduled, the core for irradiation attained the initial criticality on November 22, and the works of constructing the core were completed on December 23, 1982. Thereafter, the 100 MW performance test was begun. Various experience and valuable data were obtained in the regular inspection and the maintenance and repair works carried out at the same time, regarding the operation and maintenance of the Joyo facilities. (Kako, I.)
The latest general chemistry

International Nuclear Information System (INIS)

Ryu, Geun Bae; Choi, Se Yeong; Kim, Chin Yeong; Yoon, Gil Jung; Lee, Eun Seok; Seo, Moon Gyu

1995-02-01

This book deals with the latest general chemistry, which is comprised of twenty-three chapters, the contents of this book are introduction, theory of atoms and molecule, chemical formula and a chemical reaction formula, structure of atoms, nature of atoms and the periodic table, structure of molecule and spectrum, gas, solution, solid, chemical combination, chemical reaction speed, chemical equilibrium, thermal chemistry, oxidation-reduction, electrochemistry, acid-base, complex, aquatic chemistry, air chemistry, nuclear chemistry, metal and nonmetal, organic chemistry and biochemistry. It has exercise in the end of each chapter.
Extraction of Organochlorine Pesticides from Plastic Pellets and Plastic Type Analysis.

Science.gov (United States)

Pflieger, Marilyne; Makorič, Petra; Kovač Viršek, Manca; Koren, Špela

2017-07-01

Plastic resin pellets, categorized as microplastics (≤5 mm in diameter), are small granules that can be unintentionally released to the environment during manufacturing and transport. Because of their environmental persistence, they are widely distributed in the oceans and on beaches all over the world. They can act as a vector of potentially toxic organic compounds (e.g., polychlorinated biphenyls) and might consequently negatively affect marine organisms. Their possible impacts along the food chain are not yet well understood. In order to assess the hazards associated with the occurrence of plastic pellets in the marine environment, it is necessary to develop methodologies that allow for rapid determination of associated organic contaminant levels. The present protocol describes the different steps required for sampling resin pellets, analyzing adsorbed organochlorine pesticides (OCPs) and identifying the plastic type. The focus is on the extraction of OCPs from plastic pellets by means of a pressurized fluid extractor (PFE) and on the polymer chemical analysis applying Fourier Transform-InfraRed (FT-IR) spectroscopy. The developed methodology focuses on 11 OCPs and related compounds, including dichlorodiphenyltrichloroethane (DDT) and its two main metabolites, lindane and two production isomers, as well as the two biologically active isomers of technical endosulfan. This protocol constitutes a simple and rapid alternative to existing methodology for evaluating the concentration of organic contaminants adsorbed on plastic pieces.
Computational strain gradient crystal plasticity

DEFF Research Database (Denmark)

Niordson, Christian Frithiof; Kysar, Jeffrey W.

2014-01-01

A numerical method for viscous strain gradient crystal plasticity theory is presented, which incorporates both energetic and dissipative gradient effects. The underlying minimum principles are discussed as well as convergence properties of the proposed finite element procedure. Three problems...... of plane crystal plasticity are studied: pure shear of a single crystal between rigid platens as well as plastic deformation around cylindrical voids in hexagonal close packed and face centered cubic crystals. Effective in-plane constitutive slip parameters for plane strain deformation of specifically...... oriented face centered cubic crystals are developed in terms of the crystallographic slip parameters. The effect on geometrically necessary dislocation structures introduced by plastic deformation is investigated as a function of the ratio of void radius to plasticity length scale....
Imaging brain plasticity after trauma

Institute of Scientific and Technical Information of China (English)

Zhifeng Kou; Armin Iraji

2014-01-01

The brain is highly plastic after stroke or epilepsy;however, there is a paucity of brain plasticity investigation after traumatic brain injury (TBI). This mini review summarizes the most recent evidence of brain plasticity in human TBI patients from the perspective of advanced magnetic resonance imaging. Similar to other forms of acquired brain injury, TBI patients also demonstrat-ed both structural reorganization as well as functional compensation by the recruitment of other brain regions. However, the large scale brain network alterations after TBI are still unknown, and the ifeld is still short of proper means on how to guide the choice of TBI rehabilitation or treat-ment plan to promote brain plasticity. The authors also point out the new direction of brain plas-ticity investigation.
Constraints on the evolution of phenotypic plasticity

DEFF Research Database (Denmark)

Murren, Courtney J; Auld, Josh R.; Callahan, Hilary S

2015-01-01

Phenotypic plasticity is ubiquitous and generally regarded as a key mechanism for enabling organisms to survive in the face of environmental change. Because no organism is infinitely or ideally plastic, theory suggests that there must be limits (for example, the lack of ability to produce...... an optimal trait) to the evolution of phenotypic plasticity, or that plasticity may have inherent significant costs. Yet numerous experimental studies have not detected widespread costs. Explicitly differentiating plasticity costs from phenotype costs, we re-evaluate fundamental questions of the limits...... to the evolution of plasticity and of generalists vs specialists. We advocate for the view that relaxed selection and variable selection intensities are likely more important constraints to the evolution of plasticity than the costs of plasticity. Some forms of plasticity, such as learning, may be inherently...
Analytical chemistry instrumentation

International Nuclear Information System (INIS)

Laing, W.R.

1986-01-01

In nine sections, 48 chapters cover 1) analytical chemistry and the environment 2) environmental radiochemistry 3) automated instrumentation 4) advances in analytical mass spectrometry 5) fourier transform spectroscopy 6) analytical chemistry of plutonium 7) nuclear analytical chemistry 8) chemometrics and 9) nuclear fuel technology
Recycling of packing plastics

International Nuclear Information System (INIS)

Gintenreiter-Koegl, S.

2001-05-01

The ordinance on the avoidance of packaging waste was a serious intervention in the public and private waste management in Austria. Above all the high expenses for an overall packaging waste collection and the recycling of packaging plastics were criticized. The landfill ordinance comes into force in 2004 and this means another major change in the Austrian waste management system. In the course of this change the overall collection and the recycling and recovery of waste streams, especially of the high caloric plastics waste, have to be discussed again. The goal of this work was on the one hand to develop and adapt the hydrocracking process for the recovery of mixed plastics waste and to show a possible application in Austria. On the other hand the work shows the technical, ecological and economical conditions for packaging plastics recycling and recovery in order to find optimum applications for the processes and to examine their contribution to a sustainable development. A hydrocracking test plant for the processing of mixed plastic wastes was built and had been running for about three years. The tests were carried out successfully and the suitability of the technology for the recovery of packaging plastics could be shown. Results show at least a 35 % yield of fuel. The hydrocracking technology is quite common in the oil industries and therefore an integration on a refinery site is suggested. (author)
Is Chemistry Attractive for Pupils? Czech Pupils' Perception of Chemistry

Science.gov (United States)

Kubiatko, Milan

2015-01-01

Chemistry is an important subject due to understanding the composition and structure of the things around us. The main aim of the study was to find out the perception of chemistry by lower secondary school pupils. The partial aims were to find out the influence of gender, year of study and favorite subject on the perception of chemistry. The…
Tanzania Veterinary Journal - Vol 32, No 1 (2017)

African Journals Online (AJOL)

Tanzania Veterinary Journal - Vol 32, No 1 (2017) ... factors for porcine cysticercosis transmission and animal welfare in selected villages in Nyasa, Tanzania ... Thoracic radiographic anatomy in sheep · EMAIL FULL TEXT EMAIL FULL TEXT
African Research Review - Vol 5, No 1 (2011)

African Journals Online (AJOL)

African Research Review - Vol 5, No 1 (2011) .... Gender and Occupational Preferences among Senior High School Students in Cross River State ... Academic Achievement in Physics · EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT
Influence of preliminary plastic deformation on plasticity characteristics and structure of armco-iron

International Nuclear Information System (INIS)

Vergazov, A.N.; Rybin, V.V.; Meshkov, Yu.Ya.; Moskvina, V.A.; Serditova, T.N.

1990-01-01

Effect of preliminary plastic deformation (PPD) by drawing on the maximum plasticity characteristics (critical rupture strain) ε c , general δ and uniform δ p relative elongation and on the structure of armco-iron in a wide range of PPD degree change (e=0-4.6) is studied. It is ascertained that with e growth the metal plastic properties at T test =77 and 293 K change in a different way. In particular, the critical strain ε c increases monotonously at 77 K and reduces at 293 K. It is shown that all changes of mechanical characteristics observed with e increase are conditioned by the development of fragmentation process in armco-iron. The data obtained are discussed from the veiwpoint of the developed plastic deformation physics concepts
Plastic accumulation in the Mediterranean sea.

Directory of Open Access Journals (Sweden)

Andrés Cózar

Full Text Available Concentrations of floating plastic were measured throughout the Mediterranean Sea to assess whether this basin can be regarded as a great accumulation region of plastic debris. We found that the average density of plastic (1 item per 4 m2, as well as its frequency of occurrence (100% of the sites sampled, are comparable to the accumulation zones described for the five subtropical ocean gyres. Plastic debris in the Mediterranean surface waters was dominated by millimeter-sized fragments, but showed a higher proportion of large plastic objects than that present in oceanic gyres, reflecting the closer connection with pollution sources. The accumulation of floating plastic in the Mediterranean Sea (between 1,000 and 3,000 tons is likely related to the high human pressure together with the hydrodynamics of this semi-enclosed basin, with outflow mainly occurring through a deep water layer. Given the biological richness and concentration of economic activities in the Mediterranean Sea, the affects of plastic pollution on marine and human life are expected to be particularly frequent in this plastic accumulation region.
Plastic Accumulation in the Mediterranean Sea

KAUST Repository

Có zar, André s; Sanz-Martí n, Marina; Martí , Elisa; Gonzá lez-Gordillo, J. Ignacio; Ubeda, Bá rbara; Gá lvez, José Á .; Irigoien, Xabier; Duarte, Carlos M.

2015-01-01

Concentrations of floating plastic were measured throughout the Mediterranean Sea to assess whether this basin can be regarded as a great accumulation region of plastic debris. We found that the average density of plastic (1 item per 4 m2), as well as its frequency of occurrence (100% of the sites sampled), are comparable to the accumulation zones described for the five subtropical ocean gyres. Plastic debris in the Mediterranean surface waters was dominated by millimeter-sized fragments, but showed a higher proportion of large plastic objects than that present in oceanic gyres, reflecting the closer connection with pollution sources. The accumulation of floating plastic in the Mediterranean Sea (between 1,000 and 3,000 tons) is likely related to the high human pressure together with the hydrodynamics of this semi-enclosed basin, with outflow mainly occurring through a deep water layer. Given the biological richness and concentration of economic activities in the Mediterranean Sea, the affects of plastic pollution on marine and human life are expected to be particularly frequent in this plastic accumulation region.
Nano-plastics in the aquatic environment.

Science.gov (United States)

Mattsson, K; Hansson, L-A; Cedervall, T

2015-10-01

The amount of plastics released to the environment in modern days has increased substantially since the development of modern plastics in the early 1900s. As a result, concerns have been raised by the public about the impact of plastics on nature and on, specifically, aquatic wildlife. Lately, much attention has been paid to macro- and micro-sized plastics and their impact on aquatic organisms. However, micro-sized plastics degrade subsequently into nano-sizes whereas nano-sized particles may be released directly into nature. Such particles have a different impact on aquatic organisms than larger pieces of plastic due to their small size, high surface curvature, and large surface area. This review describes the possible sources of nano-sized plastic, its distribution and behavior in nature, the impact of nano-sized plastic on the well-being of aquatic organisms, and the difference of impact between nano- and micro-sized particles. We also identify research areas which urgently need more attention and suggest experimental methods to obtain useful data.
Integrating Hebbian and homeostatic plasticity: introduction.

Science.gov (United States)

Fox, Kevin; Stryker, Michael

2017-03-05

Hebbian plasticity is widely considered to be the mechanism by which information can be coded and retained in neurons in the brain. Homeostatic plasticity moves the neuron back towards its original state following a perturbation, including perturbations produced by Hebbian plasticity. How then does homeostatic plasticity avoid erasing the Hebbian coded information? To understand how plasticity works in the brain, and therefore to understand learning, memory, sensory adaptation, development and recovery from injury, requires development of a theory of plasticity that integrates both forms of plasticity into a whole. In April 2016, a group of computational and experimental neuroscientists met in London at a discussion meeting hosted by the Royal Society to identify the critical questions in the field and to frame the research agenda for the next steps. Here, we provide a brief introduction to the papers arising from the meeting and highlight some of the themes to have emerged from the discussions.This article is part of the themed issue 'Integrating Hebbian and homeostatic plasticity'. © 2017 The Author(s).
Plastic Accumulation in the Mediterranean Sea

KAUST Repository

Cózar, Andrés

2015-04-01

Concentrations of floating plastic were measured throughout the Mediterranean Sea to assess whether this basin can be regarded as a great accumulation region of plastic debris. We found that the average density of plastic (1 item per 4 m2), as well as its frequency of occurrence (100% of the sites sampled), are comparable to the accumulation zones described for the five subtropical ocean gyres. Plastic debris in the Mediterranean surface waters was dominated by millimeter-sized fragments, but showed a higher proportion of large plastic objects than that present in oceanic gyres, reflecting the closer connection with pollution sources. The accumulation of floating plastic in the Mediterranean Sea (between 1,000 and 3,000 tons) is likely related to the high human pressure together with the hydrodynamics of this semi-enclosed basin, with outflow mainly occurring through a deep water layer. Given the biological richness and concentration of economic activities in the Mediterranean Sea, the affects of plastic pollution on marine and human life are expected to be particularly frequent in this plastic accumulation region.
Plastic accumulation in the Mediterranean sea.

Science.gov (United States)

Cózar, Andrés; Sanz-Martín, Marina; Martí, Elisa; González-Gordillo, J Ignacio; Ubeda, Bárbara; Gálvez, José Á; Irigoien, Xabier; Duarte, Carlos M

2015-01-01

Concentrations of floating plastic were measured throughout the Mediterranean Sea to assess whether this basin can be regarded as a great accumulation region of plastic debris. We found that the average density of plastic (1 item per 4 m2), as well as its frequency of occurrence (100% of the sites sampled), are comparable to the accumulation zones described for the five subtropical ocean gyres. Plastic debris in the Mediterranean surface waters was dominated by millimeter-sized fragments, but showed a higher proportion of large plastic objects than that present in oceanic gyres, reflecting the closer connection with pollution sources. The accumulation of floating plastic in the Mediterranean Sea (between 1,000 and 3,000 tons) is likely related to the high human pressure together with the hydrodynamics of this semi-enclosed basin, with outflow mainly occurring through a deep water layer. Given the biological richness and concentration of economic activities in the Mediterranean Sea, the affects of plastic pollution on marine and human life are expected to be particularly frequent in this plastic accumulation region.

Plastic Accumulation in the Mediterranean Sea

Science.gov (United States)

Cózar, Andrés; Sanz-Martín, Marina; Martí, Elisa; González-Gordillo, J. Ignacio; Ubeda, Bárbara; Gálvez, José Á.; Irigoien, Xabier; Duarte, Carlos M.

2015-01-01

Concentrations of floating plastic were measured throughout the Mediterranean Sea to assess whether this basin can be regarded as a great accumulation region of plastic debris. We found that the average density of plastic (1 item per 4 m2), as well as its frequency of occurrence (100% of the sites sampled), are comparable to the accumulation zones described for the five subtropical ocean gyres. Plastic debris in the Mediterranean surface waters was dominated by millimeter-sized fragments, but showed a higher proportion of large plastic objects than that present in oceanic gyres, reflecting the closer connection with pollution sources. The accumulation of floating plastic in the Mediterranean Sea (between 1,000 and 3,000 tons) is likely related to the high human pressure together with the hydrodynamics of this semi-enclosed basin, with outflow mainly occurring through a deep water layer. Given the biological richness and concentration of economic activities in the Mediterranean Sea, the affects of plastic pollution on marine and human life are expected to be particularly frequent in this plastic accumulation region. PMID:25831129
Americium behaviour in plastic vessels

Energy Technology Data Exchange (ETDEWEB)

Legarda, F.; Herranz, M. [Departamento de Ingenieria Nuclear y Mecanica de Fluidos, Escuela Tecnica Superior de Ingenieria de Bilbao, Universidad del Pais Vasco (UPV/EHU), Alameda de Urquijo s/n, 48013 Bilbao (Spain); Idoeta, R., E-mail: raquel.idoeta@ehu.e [Departamento de Ingenieria Nuclear y Mecanica de Fluidos, Escuela Tecnica Superior de Ingenieria de Bilbao, Universidad del Pais Vasco (UPV/EHU), Alameda de Urquijo s/n, 48013 Bilbao (Spain); Abelairas, A. [Departamento de Ingenieria Nuclear y Mecanica de Fluidos, Escuela Tecnica Superior de Ingenieria de Bilbao, Universidad del Pais Vasco (UPV/EHU), Alameda de Urquijo s/n, 48013 Bilbao (Spain)

2010-07-15

The adsorption of {sup 241}Am dissolved in water in different plastic storage vessels was determined. Three different plastics were investigated with natural and distilled waters and the retention of {sup 241}Am by these plastics was studied. The same was done by varying vessel agitation time, vessel agitation speed, surface/volume ratio of water in the vessels and water pH. Adsorptions were measured to be between 0% and 70%. The adsorption of {sup 241}Am is minimized with no water agitation, with PET or PVC plastics, and by water acidification.
Americium behaviour in plastic vessels

International Nuclear Information System (INIS)

Legarda, F.; Herranz, M.; Idoeta, R.; Abelairas, A.

2010-01-01

The adsorption of 241 Am dissolved in water in different plastic storage vessels was determined. Three different plastics were investigated with natural and distilled waters and the retention of 241 Am by these plastics was studied. The same was done by varying vessel agitation time, vessel agitation speed, surface/volume ratio of water in the vessels and water pH. Adsorptions were measured to be between 0% and 70%. The adsorption of 241 Am is minimized with no water agitation, with PET or PVC plastics, and by water acidification.
Towards "Bildung"-Oriented Chemistry Education

Science.gov (United States)

Sjöström, Jesper

2013-01-01

This paper concerns "Bildung"-oriented chemistry education, based on a reflective and critical discourse of chemistry. It is contrasted with the dominant type of chemistry education, based on the mainstream discourse of chemistry. "Bildung"-oriented chemistry education includes not only content knowledge in chemistry, but also…
Green Chemistry Metrics with Special Reference to Green Analytical Chemistry

Directory of Open Access Journals (Sweden)

Marek Tobiszewski

2015-06-01

Full Text Available The concept of green chemistry is widely recognized in chemical laboratories. To properly measure an environmental impact of chemical processes, dedicated assessment tools are required. This paper summarizes the current state of knowledge in the field of development of green chemistry and green analytical chemistry metrics. The diverse methods used for evaluation of the greenness of organic synthesis, such as eco-footprint, E-Factor, EATOS, and Eco-Scale are described. Both the well-established and recently developed green analytical chemistry metrics, including NEMI labeling and analytical Eco-scale, are presented. Additionally, this paper focuses on the possibility of the use of multivariate statistics in evaluation of environmental impact of analytical procedures. All the above metrics are compared and discussed in terms of their advantages and disadvantages. The current needs and future perspectives in green chemistry metrics are also discussed.
Green Chemistry Metrics with Special Reference to Green Analytical Chemistry.

Science.gov (United States)

Tobiszewski, Marek; Marć, Mariusz; Gałuszka, Agnieszka; Namieśnik, Jacek

2015-06-12

The concept of green chemistry is widely recognized in chemical laboratories. To properly measure an environmental impact of chemical processes, dedicated assessment tools are required. This paper summarizes the current state of knowledge in the field of development of green chemistry and green analytical chemistry metrics. The diverse methods used for evaluation of the greenness of organic synthesis, such as eco-footprint, E-Factor, EATOS, and Eco-Scale are described. Both the well-established and recently developed green analytical chemistry metrics, including NEMI labeling and analytical Eco-scale, are presented. Additionally, this paper focuses on the possibility of the use of multivariate statistics in evaluation of environmental impact of analytical procedures. All the above metrics are compared and discussed in terms of their advantages and disadvantages. The current needs and future perspectives in green chemistry metrics are also discussed.
GLOBAL JOURNAL OF SOCIAL SCIENCES VOL 8, NO

African Journals Online (AJOL)

Ada

GLOBAL JOURNAL OF SOCIAL SCIENCES VOL 8, NO. ... media. From the over fifty tertiary institutions in the country graduates are churned .... few were collected at the contact addresses, ... acquisition is paramount for successful job hunting.
Handbook on the physics and chemistry of rare earths

International Nuclear Information System (INIS)

Gschneidner, K.A. Jr.; Eyring, L.

1982-01-01

This handbook is a six-volume work which covers the entire rare earth field in an integrated manner. Each chapter is a comprehensive, up-to-date, critical review of a particular segment of the field. The first volume is devoted to the rare earth metals, the second to rare earth alloys and intermetallics, and the third and fourth volumes to the non-metallic rare earth materials, including solutions, complexes and bioinorganic substances, in addition to solid inorganic compounds. The electronic structure of these unique elements is the primary basis of understanding their physical, metallurgical and chemical natures. The interrelationship of the 4f and valence electrons and the observed optical, electrical, magnetic, crystallographic, elastic, thermal, mechanical, chemical, geochemical and biological behaviors is brought forth time and again throughout the chapters. Also discussed are the preparative, separation and solution chemistry of the elements and their compounds and the various chemical and physical analytical methods for determining the rare earths in various materials and impurities in a rare earth matrix. Vol. 5 is a update complement of the previous volumes. Volume 6 is concerned with ternary and higher order materials. (Auth.)
Sustainable reverse logistics for household plastic waste

NARCIS (Netherlands)

Bing, X.

2014-01-01

Summary of the thesis titled “Sustainable Reverse Logistics for Household Plastic Waste”

PhD Candidate: Xiaoyun Bing

Recycled plastic can be used in the manufacturing of plastic products to reduce the use of virgin plastics material. The cost of recycled plastics is usually lower
AFRREV STECH, Vol. 3(1) February, 2014

African Journals Online (AJOL)

Toshiba

Indexed African Journals Online: www.ajol.info. AFRREV STECH. An International Journal of Science and Technology. Bahir Dar, Ethiopia. Vol. 3 (1), S/No 6, February, 2014: 1-11. ISSN 2225-8612 (Print) ISSN 2227-5444 (Online). EFFECTS OF DEFORESTATION ON NATURAL. BIO-DIVERSITY IN DELTA NORTH ...
Size effects in crystal plasticity

DEFF Research Database (Denmark)

Borg, Ulrik

2007-01-01

Numerical analyses of plasticity size effects have been carried out for different problems using a developed strain gradient crystal plasticiy theory. The theory employs higher order stresses as work conjugates to slip gradients and uses higher order boundary conditions. Problems on localization...... of plastic flow in a single crystal, grain boundary effects in a bicrystal, and grain size effects in a polycrystal are studied. Single crystals containing micro-scale voids have also been analyzed at different loading conditions with focus on the stress and deformation fields around the voids, on void...... growth and interaction between neighboring voids, and on a comparison between the developed strain gradient crystal plasticity theory and a discrete dislocation plasticity theory. Furthermore, voids and rigid inclusions in isotropic materials have been studied using a strain gradient plasticity theory...
Tracking chemistry self-efficacy and achievement in a preparatory chemistry course

Science.gov (United States)

Garcia, Carmen Alicia

Self-efficacy is a person's own perception about performing a task with a certain level of proficiency (Bandura, 1986). An important affective aspect of learning chemistry is chemistry self-efficacy (CSE). Several researchers have found chemistry self-efficacy to be a fair predictor of achievement in chemistry. This study was done in a college preparatory chemistry class for science majors exploring chemistry self-efficacy and its change as it relates to achievement. A subscale of CAEQ, Chemistry Attitudes and Experiences Questionnaire (developed by Dalgety et al, 2003) as well as student interviews were used to determine student chemistry self-efficacy as it changed during the course. The questionnaire was given to the students five times during the semester: in the first class and the class before each the four tests taken through the semester. Twenty-six students, both men and women, of the four major races/ethnicities were interviewed three times during the semester and events that triggered changes in CSE were followed through the interviews. HLM (hierarchical linear modeling) was used to model the results of the CSE surveys. Among the findings, women who started at significantly lower CSE than men accomplished a significant gain by the end of the semester. Blacks' CSE trends through the semester were found to be significantly different from the rest of the ethnicities.
Green Chemistry Pedagogy

Science.gov (United States)

Kolopajlo, Larry

2017-02-01

This chapter attempts to show how the practice of chemistry teaching and learning is enriched by the incorporation of green chemistry (GC) into lectures and labs. To support this viewpoint, evidence from a wide range of published papers serve as a cogent argument that GC attracts and engages both science and nonscience students, enhances chemistry content knowledge, and improves the image of the field, while preparing the world for a sustainable future. Published pedagogy associated with green and sustainable chemistry is critically reviewed and discussed.
Transuranic Computational Chemistry.

Science.gov (United States)

Kaltsoyannis, Nikolas

2018-02-26

Recent developments in the chemistry of the transuranic elements are surveyed, with particular emphasis on computational contributions. Examples are drawn from molecular coordination and organometallic chemistry, and from the study of extended solid systems. The role of the metal valence orbitals in covalent bonding is a particular focus, especially the consequences of the stabilization of the 5f orbitals as the actinide series is traversed. The fledgling chemistry of transuranic elements in the +II oxidation state is highlighted. Throughout, the symbiotic interplay of experimental and computational studies is emphasized; the extraordinary challenges of experimental transuranic chemistry afford computational chemistry a particularly valuable role at the frontier of the periodic table. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.
Author Details

African Journals Online (AJOL)

Abstract PDF · Vol 3, No 2 (2013) - Articles Students' anxiety towards the learning of chemistry in some Ethiopian Universities Abstract PDF · Vol 3, No 2 (2013) - Articles Effects of technology driven pedagogy applications on the comprehension of complex and abstract concepts of chemical equilibrium. Abstract PDF · Vol 3, ...
SYNTHESIS AND CHARACTERIZATION OF BIODEGRDABLE PLASTIC FROM CASAVA STARCH AND ALOE VERA EXTRACT WITH GLYCEROL PLASTICIZER

Directory of Open Access Journals (Sweden)

Mery Apriyani

2016-05-01

Full Text Available Synthesis and characterizations of Biodegradable Plastic made of Cassava Waste Starch, glycerol, acetic acid and Aloe vera extract has done. The aims of this research are to study the influence of addition of aloe vera extract in plastics mechanics properties, water vapor transmission rate and biodegradation. There are five main steps in this research, extraction of aloe vera, cassava starch preparation from cassava waste, preparations, characterization and biodegradability study of biodegradable plastic. The addition variations of aloe vera extract that used in this research are 0.01; 0.03; 0.05; 0.07 and 0.14 grams. Results showed that the addition of aloe Vera tends to increased biodegrable plastic thickness to 0.01 mm and elongation to 32.07%. However, biodegradable plastic tensile strength tends to decreased to 23.95 Mpa. Optimum tensile strength is 3.90 Mpa and elongation is 34.43%. Optimum water vapor transmission rate is 2.40 g/m2hours. Biodegradation study of biodegradable plastic showed that addition of aloe vera extract doesn’t significantly influence in plastic degradations.
African Health Sciences - Vol 15, No 4 (2015)

African Journals Online (AJOL)

African Health Sciences. ... African Health Sciences - Vol 15, No 4 (2015) .... H Madubedube, Andre P Kengne, Rajiv T Erasmus, Tahir S Pillay, Tandi E ... on lung function and cardiorespiratory fitness in both cigarette and hookah smokers.
Chemistry Notes

Science.gov (United States)

School Science Review, 1976

1976-01-01

Described are eight chemistry experiments and demonstrations applicable to introductory chemistry courses. Activities include: measure of lattice enthalpy, Le Chatelier's principle, decarboxylation of soap, use of pocket calculators in pH measurement, and making nylon. (SL)
Fundamentals of nuclear chemistry

International Nuclear Information System (INIS)

Matel, L.; Dulanska, S.

2013-01-01

This text-book is an introductory text in nuclear chemistry and radiochemistry, aimed on university undergraduate students in chemistry and related disciplines (physics, nuclear engineering). It covers the key aspects of modern nuclear chemistry. The text begins with basic theories in contemporary physics. It relates nuclear phenomena to key divisions of chemistry such as atomic structure, spectroscopy, equilibria and kinetics. It also gives an introduction to sources of ionizing radiation, detection of ionizing radiation, nuclear power industry and accident on nuclear installations as well as basic knowledge's of radiobiology. This book is essential reading for those taking a first course in nuclear chemistry and is a useful companion to other volumes in physical and analytical chemistry. It will also be of use to those new to working in nuclear chemistry or radiochemistry.
Nuclear- and radiochemistry. Vol. 2. Modern applications

International Nuclear Information System (INIS)

Roesch, Frank

2016-01-01

This work is conceived to meet the demand of state-of-the-art literature to teach the fundamentals as well as the modern applications of nuclear chemistry. The work will consist of two volumes: the first one covering the basics of nuclear chemistry such as the relevant parameters of instable atomic nuclei, the various modi of radioactive transmutations, the corresponding types of radiation including their detection and dosimetry, and finally the mechanisms of nuclear reactions. The second volume addresses relevant fields of nuclear chemistry, such as the chemistry of radioactive elements, application of radioactive nuclei in life sciences, nuclear energy, waste managements and environmental aspects, radiochemical separations, radioanalytical and spectroscopic methods, etc. Here, leading experts will contribute up-to-date knowledge on the most important application of nuclear chemistry.

Handbook of heterocyclic chemistry

National Research Council Canada - National Science Library

Katritzky, Alan R

2010-01-01

... Heterocyclic Chemistry I (1984) Comprehensive Heterocyclic Chemistry II (1996) Comprehensive Heterocyclic Chemistry III (2008) Comprehensive Organic Functional Group Transformations I (1995) Compreh...
Americium behaviour in plastic vessels.

Science.gov (United States)

Legarda, F; Herranz, M; Idoeta, R; Abelairas, A

2010-01-01

The adsorption of (241)Am dissolved in water in different plastic storage vessels was determined. Three different plastics were investigated with natural and distilled waters and the retention of (241)Am by these plastics was studied. The same was done by varying vessel agitation time, vessel agitation speed, surface/volume ratio of water in the vessels and water pH. Adsorptions were measured to be between 0% and 70%. The adsorption of (241)Am is minimized with no water agitation, with PET or PVC plastics, and by water acidification. Copyright 2009 Elsevier Ltd. All rights reserved.
African Health Sciences - Vol 13, No 2 (2013)

African Journals Online (AJOL)

African Health Sciences. ... African Health Sciences - Vol 13, No 2 (2013) ... S Musisi, D Akena, E Nakimuli-Mpungu, C Abbo, J Okello, 205-218 .... Alcohol consumption and cigarette smoking pattern among brothelbased female sex workers in ...
Plastics control paraffin buildup

Energy Technology Data Exchange (ETDEWEB)

1965-06-01

Paraffin buildup in producing oil wells has been virtually eliminated by the use of plastic-coated sucker rods. The payout of the plasticing process is generally reached in less than a year, and the paraffin buildup may be inhibited for 10 yr or longer. Most of the plants applying plastic coatings to sucker rods are now fully automated, though a few still offer the hand-sprayed coating that some operators prefer. The several steps involved are described. The ideal plastic for the job is resistant to chemicals at high and low temperatures, flexible, has good adhesion, abrasion resistance, impact resistance, and a smooth glossy finish. The phenol aldehyde and epoxy resins presently offered by the industry fulfill these specifications very well; the multicoating and multibaking techniques improve their performance. Due to wide variations in the severity of the paraffin problem from one oil field to another, there is no general rule to estimate the possible savings from using plastic-coated sucker rods. The process, however, does appear to do a remarkable job in controlling paraffin buildup wherever it is a problem in producing oil by pump.
Chemistry Dashboard

Science.gov (United States)

The Chemistry Dashboard is part of a suite of dashboards developed by EPA to help evaluate the safety of chemicals. The Chemistry Dashboard provides access to a variety of information on over 700,000 chemicals currently in use.
Plastics: Friend or foe?

Directory of Open Access Journals (Sweden)

O P Gupta

2018-01-01

Full Text Available Plastics has been playing a very significant role in our life. Being light weight, inexpensive and heving good insulating properties it is being used in all aspects of life, from clothes to contact lenses and from mobile phones to automobiles as well as in medical equipments, However it is not biodegradable, and while degrading to fragments it gets converted in to microplastics and nanoplastics The plastic waste is being recognized as an environmental hazard, since these micr- and nanoplastics find way from landfills to water and foods, It is said that we are not only using, but we are eating, drinking and even braething the plastics. These microplastics in body release certain hazardous chemicals and found to be disrupting functions of certain endocrine organs. Whether the rising prevalence of Diabetes, thyroid disorders or infirtility etc., are realated to the plastics?
Materials Chemistry

CERN Document Server

Fahlman, Bradley D

2011-01-01

The 2nd edition of Materials Chemistry builds on the strengths that were recognized by a 2008 Textbook Excellence Award from the Text and Academic Authors Association (TAA). Materials Chemistry addresses inorganic-, organic-, and nano-based materials from a structure vs. property treatment, providing a suitable breadth and depth coverage of the rapidly evolving materials field. The 2nd edition continues to offer innovative coverage and practical perspective throughout. After briefly defining materials chemistry and its history, seven chapters discuss solid-state chemistry, metals, semiconducting materials, organic "soft" materials, nanomaterials, and materials characterization. All chapters have been thoroughly updated and expanded with, for example, new sections on ‘soft lithographic’ patterning, ‘click chemistry’ polymerization, nanotoxicity, graphene, as well as many biomaterials applications. The polymer and ‘soft’ materials chapter represents the largest expansion for the 2nd edition. Each ch...
Motor cortical plasticity in Parkinson's disease.

Science.gov (United States)

Udupa, Kaviraja; Chen, Robert

2013-09-04

In Parkinson's disease (PD), there are alterations of the basal ganglia (BG) thalamocortical networks, primarily due to degeneration of nigrostriatal dopaminergic neurons. These changes in subcortical networks lead to plastic changes in primary motor cortex (M1), which mediates cortical motor output and is a potential target for treatment of PD. Studies investigating the motor cortical plasticity using non-invasive transcranial magnetic stimulation (TMS) have found altered plasticity in PD, but there are inconsistencies among these studies. This is likely because plasticity depends on many factors such as the extent of dopaminergic loss and disease severity, response to dopaminergic replacement therapies, development of l-DOPA-induced dyskinesias (LID), the plasticity protocol used, medication, and stimulation status in patients treated with deep brain stimulation (DBS). The influences of LID and DBS on BG and M1 plasticity have been explored in animal models and in PD patients. In addition, many other factors such age, genetic factors (e.g., brain derived neurotropic factor and other neurotransmitters or receptors polymorphism), emotional state, time of the day, physical fitness have been documented to play role in the extent of plasticity induced by TMS in human studies. In this review, we summarize the studies that investigated M1 plasticity in PD and demonstrate how these afore-mentioned factors affect motor cortical plasticity in PD. We conclude that it is important to consider the clinical, demographic, and technical factors that influence various plasticity protocols while developing these protocols as diagnostic or prognostic tools in PD. We also discuss how the modulation of cortical excitability and the plasticity with these non-invasive brain stimulation techniques facilitate the understanding of the pathophysiology of PD and help design potential therapeutic possibilities in this disorder.
Quantum chemistry

CERN Document Server

Lowe, John P

1993-01-01

Praised for its appealing writing style and clear pedagogy, Lowe's Quantum Chemistry is now available in its Second Edition as a text for senior undergraduate- and graduate-level chemistry students. The book assumes little mathematical or physical sophistication and emphasizes an understanding of the techniques and results of quantum chemistry, thus enabling students to comprehend much of the current chemical literature in which quantum chemical methods or concepts are used as tools. The book begins with a six-chapter introduction of standard one-dimensional systems, the hydrogen atom,
Process for remediation of plastic waste

Science.gov (United States)

Pol, Vilas G [Westmont, IL; Thiyagarajan, Pappannan [Germantown, MD

2012-04-10

A single step process for degrading plastic waste by converting the plastic waste into carbonaceous products via thermal decomposition of the plastic waste by placing the plastic waste into a reactor, heating the plastic waste under an inert or air atmosphere until the temperature of 700.degree. C. is achieved, allowing the reactor to cool down, and recovering the resulting decomposition products therefrom. The decomposition products that this process yields are carbonaceous materials, and more specifically egg-shaped and spherical-shaped solid carbons. Additionally, in the presence of a transition metal compound, this thermal decomposition process produces multi-walled carbon nanotubes.
AJESMS Vol 9 2011 October 23 2012 final

African Journals Online (AJOL)

Owner

2011-10-23

Oct 23, 2011 ... African Journal of Educational Studies in Mathematics and Sciences Vol. ... alveolar re-circulation and gravity orientation are key factors in determining the ..... Comp. Biomed. Res. 3, pp 675-689. Pich, J. (1972). Theory of ...
African Research Review - Vol 4, No 4 (2010)

African Journals Online (AJOL)

African Research Review - Vol 4, No 4 (2010) .... Educational Policy and Technological Development in Africa: An X-Ray of Problems and Solutions in the .... Tradition and Art Appreciation: A Boost to Cultural Tourism in Nigeria · EMAIL FREE ...
Microstructure and surface chemistry of amorphous alloys important to their friction and wear behavior

Science.gov (United States)

Miyoshi, K.; Buckley, D. H.

1986-01-01

An investigation was conducted to examine the microstructure and surface chemistry of amorphous alloys, and their effects on tribological behavior. The results indicate that the surface oxide layers present on amorphous alloys are effective in providing low friction and a protective film against wear in air. Clustering and crystallization in amorphous alloys can be enhanced as a result of plastic flow during the sliding process at a low sliding velocity, at room temperature. Clusters or crystallines with sizes to 150 nm and a diffused honeycomb-shaped structure are produced on sizes to 150 nm and a diffused honeycomb-shaped structure are produced on the wear surface. Temperature effects lead to drastic changes in surface chemistry and friction behavior of the alloys at temperatures to 750 C. Contaminants can come from the bulk of the alloys to the surface upon heating and impart to the surface oxides at 350 C and boron nitride above 500 C. The oxides increase friction while the boron nitride reduces friction drastically in vacuum.
Author Details

African Journals Online (AJOL)

Ezeokeke, CT. Vol 40, No 1 (2013) - Articles Performance of local fowls fed plantain peels meal. Abstract · Vol 39, No 2 (2012) - Articles Biometric measurements of body and internal organ traits of indigenous chickens on free range in South-Eastern Nigeria Abstract · Vol 42, No 2 (2015) - Articles Blood chemistry and ...
DESIGNERS’ KNOWLEDGE IN PLASTICS

DEFF Research Database (Denmark)

Eriksen, Kaare

2013-01-01

The Industrial designers’ knowledge in plastics materials and manufacturing principles of polymer products is very important for the innovative strength of the industry, according to a group of Danish plastics manufacturers, design students and practicing industrial designers. These three groups ...
Annual Report 1984. Chemistry Department

DEFF Research Database (Denmark)

Funck, Jytte; Nielsen, Ole John

This report contains a brief survey of the main activities in the Chemistry Department. All articles and reports published and lectures given in 1984 are presented. The facilities and equipment are mentioned briefly. The activities are divided into the following groups: radioisotope chemistry, an......, analytical- and organic chemistry, environmental chemistry, polymer chemistry, geochemistry and waste disposal, radical chemistry, positron annihilation, mineral processing, and general.......This report contains a brief survey of the main activities in the Chemistry Department. All articles and reports published and lectures given in 1984 are presented. The facilities and equipment are mentioned briefly. The activities are divided into the following groups: radioisotope chemistry...
Physics at LEP2. Vol. 2

International Nuclear Information System (INIS)

Altarelli, G.; Sjoestrand, T.; Zwirner, F.

1995-01-01

This is final report of the Workshop on Physics at LEP2, held at CERN during 1995. The first part of vol. 1 is devoted to aspects of machine physics of particular relevance to experiments, including the energy, luminosity and interaction regions, as well as the measurement of beam energy. The second part of vol. 1 is a relatively concise, but fairly complete, handbook on the physics of e + e - annihilation above the WW threshold and up to √s∼200 GeV. It contains discussions on WW cross-sections and distributions, W mass determination, Standard Model processes, QCD and gamma-gamma physics, as well as aspects of discovery physics, such as Higgs, new particle searches, triple gauge boson couplings and Z'. The second volume contains a review of the existing Monte Carlo generators for LEP2 physics. These include generators for WW physics, QCD and gamma-gamma processes, Bhabha scattering and discovery physics. A special effort was made to co-ordinate the different parts, with a view to achieving a systematic and balanced review of the subject, rather than just publishing a collection of separate contributions. (orig.)
Physics at LEP2. Vol. 1

International Nuclear Information System (INIS)

Altarelli, G.; Sjoestrand, T.; Zwirner, F.

1996-01-01

This is the final report of the Workshop on Physics at LEP2, held at CERN during 1995. The first part of vol. 1 is devoted to aspects of machine physics of particular relevance to experiments, including the energy, luminosity and interaction regions, as well as the measurement of beam energy. The second part of vol. 1 is a relatively concise, but fairly complete, handbook on the physics of e + e - annihilation above the WW threshold and up to √s∼200 GeV. It contains discussions on WW cross-sections and distributions, W mass determination, Standard Model processes, QCD and gamma-gamma physics, as well as aspects of discovery physics, such as Higgs, new particle searches, triple gauge boson couplings and Z'. The second volume contains a review of the existing Monte Carlo generators for LEP2 physics. These include generators for WW physics, QCD and gamma-gamma processes, Bhabha scattering and discovery physics. A special effort was made to co-ordinate the different parts, with a view to achieving a systematic and balanced review of the subject, rather than just publishing a collection of separate contributions. (orig.)
Physics at LEP2. Vol. 2

Energy Technology Data Exchange (ETDEWEB)

Altarelli, G [ed.; Sjoestrand, T [ed.; Zwirner, F [ed.

1995-02-19

This is final report of the Workshop on Physics at LEP2, held at CERN during 1995. The first part of vol. 1 is devoted to aspects of machine physics of particular relevance to experiments, including the energy, luminosity and interaction regions, as well as the measurement of beam energy. The second part of vol. 1 is a relatively concise, but fairly complete, handbook on the physics of e{sup +}e{sup -} annihilation above the WW threshold and up to {radical}s{approx}200 GeV. It contains discussions on WW cross-sections and distributions, W mass determination, Standard Model processes, QCD and gamma-gamma physics, as well as aspects of discovery physics, such as Higgs, new particle searches, triple gauge boson couplings and Z`. The second volume contains a review of the existing Monte Carlo generators for LEP2 physics. These include generators for WW physics, QCD and gamma-gamma processes, Bhabha scattering and discovery physics. A special effort was made to co-ordinate the different parts, with a view to achieving a systematic and balanced review of the subject, rather than just publishing a collection of separate contributions. (orig.).
Electron tunneling in chemistry

International Nuclear Information System (INIS)

Zamaraev, K.I.; Khajrutdinov, R.F.; Zhdanov, V.P.; Molin, Yu.N.

1985-01-01

Results of experimental and theoretical investigations are outlined systematically on electron tunnelling in chemical reactions. Mechanism of electron transport to great distances is shown to be characteristic to chemical compounds of a wide range. The function of tunnel reactions is discussed for various fields of chemistry, including radiation chemistry, electrochemistry, chemistry of solids, chemistry of surface and catalysis

Annual report 1984 Chemistry Department

International Nuclear Information System (INIS)

Funck, J.; Larsen, E.; Nielsen, O.J.

1985-03-01

This report contains a brief survey of the main activities in the Chemistry Department. All articles and reports published and lectures given in 1984 are presented. The facilities and equipment are mentioned briefly. The activities are divided into the following groups: radioisotope chemistry, analytical- and organic chemistry , environmental chemistry, polymer chemistry, geochemistry and waste disposal, radical chemistry, positron annihilation, mineral processing, and general. (author)
Annual report 1987 Chemistry Department

International Nuclear Information System (INIS)

Funck, J.; Larsen, E.; Nielsen, O.J.

1988-04-01

This report contains a brief survey of the main activities in the Chemistry Department. The names and abstracts of all articles and reports published and lectures given in 1987 are presented. The facilities and equipment are mentioned briefly. The activities are divided into the following groups: radioisotope chemistry, analytical- and organic chemistry, environmental chemistry, polymer chemistry, radical chemistry, mineral processing, and general. 13 ills., (author)
Annual report 1985 Chemistry Department

International Nuclear Information System (INIS)

Funck, J.; Larsen, E.; Nielsen, O.J.

1986-03-01

This report contains a brief survey of the main activities in the Chemistry Department. All particles and reports published and lectures given in 1985 are presented. The facilities and equipment are mentioned briefly. The activities are divided into the following groups: radioisotope chemistry, analytical- and organic chemistry, environmental chemistry, polymer chemistry, geochemistry and waste disposal, radical chemistry, positron annihilation, mineral processing, and general. (author)
Annual report 1982 chemistry department

International Nuclear Information System (INIS)

Larsen, E.; Nielsen, O.J.

1983-04-01

The work going on in the Risoe National Laboratory, Chemistry Department is briefly surveyed by a presentation of all articles and reports published in 1982. The facilities and equipment are barely mentioned. The papers are divided into eight activities: 1. neutron activation analysis 2. analytical- and organic chemistry 3. environmental chemistry 4. polymer chemistry 5. geochemistry 6. radical chemistry 7. poitron annihilation 8. uranium process chemistry. (author)
Effect of the temperature, strain rate and microstructure on flow and fracture characteristics of Ti-45Al-2Nb-2Mn+0.8vol.% TiB2 XD alloy

Science.gov (United States)

Erice, B.; Pérez-Martín, M. J.; Cendón, D. A.; Gálvez, F.

2012-05-01

A series of quasi-static and dynamic tensile tests at varying temperatures were carried out to determine the mechanical behaviour of Ti-45Al-2Nb-2Mn+0.8vol.% TiB2 XD as-HIPed alloy. The temperature for the tests ranged from room temperature to 850 ∘C. The effect of the temperature on the ultimate tensile strength, as expected, was almost negligible within the selected temperature range. Nevertheless, the plastic flow suffered some softening because of the temperature. This alloy presents a relatively low ductility; thus, a low tensile strain to failure. The dynamic tests were performed in a Split Hopkinson Tension Bar, showing an increase of the ultimate tensile strength due to the strain rate hardening effect. Johnson-Cook constitutive relation was used to model the plastic flow. A post-testing microstructural of the specimens revealed an inhomogeneous structure, consisting of lamellar α2 + γ structure and γ phase equiaxed grains in the centre, and a fully lamellar structure on the rest. The assessment of the duplex-fully lamellar area ratio showed a clear relationship between the microstructure and the fracture behaviour.
Grain Interactions in Crystal Plasticity

International Nuclear Information System (INIS)

Boyle, K.P.; Curtin, W.A.

2005-01-01

The plastic response of a sheet metal is governed by the collective response of the underlying grains. Intragranular plasticity depends on intrinsic variables such as crystallographic orientation and on extrinsic variables such as grain interactions; however, the role of the latter is not well understood. A finite element crystal plasticity formulation is used to investigate the importance of grain interactions on intragranular plastic deformation in initially untextured polycrystalline aggregates. A statistical analysis reveals that grain interactions are of equal (or more) importance for determining the average intragranular deviations from the applied strain as compared to the orientation of the grain itself. Furthermore, the influence of the surrounding grains is found to extend past nearest neighbor interactions. It is concluded that the stochastic nature of the mesoscale environment must be considered for a proper understanding of the plastic response of sheet metals at the grain-scale
Degradation of oxo-biodegradable plastic by Pleurotus ostreatus.

Science.gov (United States)

da Luz, José Maria Rodrigues; Paes, Sirlaine Albino; Nunes, Mateus Dias; da Silva, Marliane de Cássia Soares; Kasuya, Maria Catarina Megumi

2013-01-01

Growing concerns regarding the impact of the accumulation of plastic waste over several decades on the environmental have led to the development of biodegradable plastic. These plastics can be degraded by microorganisms and absorbed by the environment and are therefore gaining public support as a possible alternative to petroleum-derived plastics. Among the developed biodegradable plastics, oxo-biodegradable polymers have been used to produce plastic bags. Exposure of this waste plastic to ultraviolet light (UV) or heat can lead to breakage of the polymer chains in the plastic, and the resulting compounds are easily degraded by microorganisms. However, few studies have characterized the microbial degradation of oxo-biodegradable plastics. In this study, we tested the capability of Pleurotus ostreatus to degrade oxo-biodegradable (D2W) plastic without prior physical treatment, such as exposure to UV or thermal heating. After 45 d of incubation in substrate-containing plastic bags, the oxo-biodegradable plastic, which is commonly used in supermarkets, developed cracks and small holes in the plastic surface as a result of the formation of hydroxyl groups and carbon-oxygen bonds. These alterations may be due to laccase activity. Furthermore, we observed the degradation of the dye found in these bags as well as mushroom formation. Thus, P. ostreatus degrades oxo-biodegradable plastics and produces mushrooms using this plastic as substrate.
Degradation of oxo-biodegradable plastic by Pleurotus ostreatus.

Directory of Open Access Journals (Sweden)

José Maria Rodrigues da Luz

Full Text Available Growing concerns regarding the impact of the accumulation of plastic waste over several decades on the environmental have led to the development of biodegradable plastic. These plastics can be degraded by microorganisms and absorbed by the environment and are therefore gaining public support as a possible alternative to petroleum-derived plastics. Among the developed biodegradable plastics, oxo-biodegradable polymers have been used to produce plastic bags. Exposure of this waste plastic to ultraviolet light (UV or heat can lead to breakage of the polymer chains in the plastic, and the resulting compounds are easily degraded by microorganisms. However, few studies have characterized the microbial degradation of oxo-biodegradable plastics. In this study, we tested the capability of Pleurotus ostreatus to degrade oxo-biodegradable (D2W plastic without prior physical treatment, such as exposure to UV or thermal heating. After 45 d of incubation in substrate-containing plastic bags, the oxo-biodegradable plastic, which is commonly used in supermarkets, developed cracks and small holes in the plastic surface as a result of the formation of hydroxyl groups and carbon-oxygen bonds. These alterations may be due to laccase activity. Furthermore, we observed the degradation of the dye found in these bags as well as mushroom formation. Thus, P. ostreatus degrades oxo-biodegradable plastics and produces mushrooms using this plastic as substrate.
Degradation of Oxo-Biodegradable Plastic by Pleurotus ostreatus

Science.gov (United States)

da Luz, José Maria Rodrigues; Paes, Sirlaine Albino; Nunes, Mateus Dias; da Silva, Marliane de Cássia Soares; Kasuya, Maria Catarina Megumi

2013-01-01

Growing concerns regarding the impact of the accumulation of plastic waste over several decades on the environmental have led to the development of biodegradable plastic. These plastics can be degraded by microorganisms and absorbed by the environment and are therefore gaining public support as a possible alternative to petroleum-derived plastics. Among the developed biodegradable plastics, oxo-biodegradable polymers have been used to produce plastic bags. Exposure of this waste plastic to ultraviolet light (UV) or heat can lead to breakage of the polymer chains in the plastic, and the resulting compounds are easily degraded by microorganisms. However, few studies have characterized the microbial degradation of oxo-biodegradable plastics. In this study, we tested the capability of Pleurotus ostreatus to degrade oxo-biodegradable (D2W) plastic without prior physical treatment, such as exposure to UV or thermal heating. After 45 d of incubation in substrate-containing plastic bags, the oxo-biodegradable plastic, which is commonly used in supermarkets, developed cracks and small holes in the plastic surface as a result of the formation of hydroxyl groups and carbon-oxygen bonds. These alterations may be due to laccase activity. Furthermore, we observed the degradation of the dye found in these bags as well as mushroom formation. Thus, P. ostreatus degrades oxo-biodegradable plastics and produces mushrooms using this plastic as substrate. PMID:23967057
Desorption modeling of hydrophobic organic chemicals from plastic sheets using experimentally determined diffusion coefficients in plastics.

Science.gov (United States)

Lee, Hwang; Byun, Da-Eun; Kim, Ju Min; Kwon, Jung-Hwan

2018-01-01

To evaluate rate of migration from plastic debris, desorption of model hydrophobic organic chemicals (HOCs) from polyethylene (PE)/polypropylene (PP) films to water was measured using PE/PP films homogeneously loaded with the HOCs. The HOCs fractions remaining in the PE/PP films were compared with those predicted using a model characterized by the mass transfer Biot number. The experimental data agreed with the model simulation, indicating that HOCs desorption from plastic particles can generally be described by the model. For hexachlorocyclohexanes with lower plastic-water partition coefficients, desorption was dominated by diffusion in the plastic film, whereas desorption of chlorinated benzenes with higher partition coefficients was determined by diffusion in the aqueous boundary layer. Evaluation of the fraction of HOCs remaining in plastic films with respect to film thickness and desorption time showed that the partition coefficient between plastic and water is the most important parameter influencing the desorption half-life. Copyright © 2017 Elsevier Ltd. All rights reserved.
Atomic scale study of vacancies in Earth's inner core: effect of pressure and chemistry

Science.gov (United States)

Ritterbex, S.; Tsuchiya, T.

2017-12-01

Seismic observations of the Earth's inner core [1] remain ambiguously related to mineral physics studies of the inner core stable crystalline iron phase [2,3,4,5]. This makes it difficult to clarify the role of plastic deformation as one of the primary candidates responsible for the observed seismic anisotropy of Earth's inner core. Nonetheless, atomic self-diffusion mechanisms provide a direct link between plastic deformation and the mechanical properties of Earth's inner core stable iron phase(s). Using first-principles density functional based calculation techniques, we have studied the conjugate effect of pressure and chemistry on vacancy diffusion in HCP-, BCC- and FCC-iron by taking into account potential light alloying elements as hydrogen, silicon and sulfur. Our results show that inner core pressure highly inhibits the rate of intrinsic self-diffusion by suppressing defect concentration rather than by effecting the mobility of the defects. Moreover, we found light elements to be able to affect metallic bonding which allows for extrinsic diffusion mechanisms in iron under inner core conditions. The latter clearly enables to enhance defect concentration and hence to enhance the rate of plastic deformation. This suggests that inner core chemistry affects the rheological properties (e.g.viscosity) of iron alloys which finally should match with seismic observations. references: [1] Deuss, A., 2014. Heterogeneity and Anisotropy of Earth's inner core. An. Rev. Earth Planet. Sci. 42, 103-126. [2] Anzellini, S., Dewaele, A., Mezouar, M., Loubeyre, P., Morard, G., 2013. Melting of iron at Earth's inner core boundary based on fast X-ray diffraction. Science 340, 464-466. [3] Godwal, B.K., Gonzales-Cataldo, F., Verma, A.K., Stixrude, L., Jeanloz, R., 2015. Stability of iron crystal structures at 0.3-1.5 TPa. [4] Vocadlo, L., 2007. Ab initio calculations of the elasticity of iron and iron alloys at inner core conditions: evidence for a partially molten inner core
Liquid crystal displays with plastic substrates

Science.gov (United States)

Lueder, Ernst H.

1998-04-01

Plastic substrates for the cells of displays exhibit only 1/6 of the weight of glass substrates; they are virtually unbreakable; their flexibility allows the designer to give them a shape suppressing reflections, to realize a display board on a curved surface or meeting the requirements for an appealing styling; displays with plastics are thinner which provides a wider viewing angle. These features render them attractive for displays in portable systems such as mobile phones, pagers, smart cards, personal digital assistants (PDAs) and portable computers. Reflective displays are especially attractive as they don't need a back light. The most important requirements are the protection of plastics against gas permeation and chemical agents, the prevention of layers on plastics to crack or peel off when the plastic is bent and the development of low temperature thin film processes because the plastics, as a rule, only tolerate temperatures below 150 degrees Celsius. Bistable reflective FLC- and PSCT-displays with plastic substrates will be introduced. Special sputtered SiO2-orientation layers preserve the displayed information even if pressure or torsion is applied. MIM-addressed PDLC-displays require additional Al- or Ti-layers which provide the necessary ductility. Sputtered or PECVD-generated TFTs can be fabricated on plastics at temperatures below 150 degrees Celsius.
Atom-at-a-time chemistry

International Nuclear Information System (INIS)

Nagame, Yuichiro

2009-01-01

Several techniques of the analytical chemistry in 'Atom-at-a-time chemistry' for transactinide elements have been developed. In this report a representative example in these techniques is introduced with the results. The contents are the single-atom chemistry, the chemical experiments on transactinide elements, liquid phase chemistry (the ion exchange behavior of Rutherfordium), gas phase chemistry (the chemistry of atomic No.112 element), and future development. (M.H.)
Chemistry, Poetry, and Artistic Illustration: An Interdisciplinary Approach to Teaching and Promoting Chemistry

Science.gov (United States)

Furlan, Ping Y.; Kitson, Herbert; Andes, Cynthia

2007-10-01

This article describes a successful interdisciplinary collaboration among chemistry, humanities and English faculty members, who utilized poetry and artistic illustration to help students learn, appreciate, and enjoy chemistry. Students taking general chemistry classes were introduced to poetry writing and museum-type poster preparation during one class period. They were then encouraged to use their imagination and creativity to brainstorm and write chemistry poems or humors on the concepts and principles covered in the chemistry classes and artistically illustrate their original work on posters. The project, 2 3 months in length, was perceived by students as effective at helping them learn chemistry and express their understanding in a fun, personal, and creative way. The instructors found students listened to the directives because many posters were witty, clever, and eye-catching. They showed fresh use of language and revealed a good understanding of chemistry. The top posters were created by a mix of A-, B-, and C-level students. The fine art work, coupled with poetry, helped chemistry come alive on campus, providing an aesthetic presentation of materials that engaged the general viewer.
Afican Health Sciences Vol 9 No 2.pmd

African Journals Online (AJOL)

Administrator

African Health Sciences Vol 9 No 2 June 2009 ... Background:The under five mortality rate (U5MR) is measure of wellbeing and decreasing the U5MR by two .... under three scenarios 1-3. ... Negative indicates increase in childhood mortalities.
USSR Report Chemistry

National Research Council Canada - National Science Library

1986-01-01

Contents: Adsorption, Chemistry,Alkaloids, Analytical Chemistry, Catalysis,Chemical Industry,,Coal Gasification, Combustion, Electrochemistry,Explosives and Explosions, Fertilizers, Free Radicals, Inorganic...
Mechanistic aspects of polymer chemistry for radiation curing

International Nuclear Information System (INIS)

Dickson, Lawrence W.

1988-01-01

The chemistry of polymer production has been reviewed for the purpose of identifying suitable uses for high-energy electron accelerators in the plastics industry. High-energy radiation produces free radicals, electrons and ions in irradiated materials. These species initiate polymerization and cross-linking reactions in a manner analogous to that of chemical agents. The chemical mechanisms of radiation-induced polymerization, co-polymerization and cross-linking are compared with those of chemical and thermal initiation. Radiation polymerization can be a very fast process, but the polymerization reactions are quite exothermic, and temperature increases of up to 400 degrees Celcius may result if insufficient cooling is provided. Several approaches to reducing the temperature increase during radiation curing are presented. Chemical kinetic simulations of the radiation-induced cationic polymerization of styrene have shown that the effect of water inhibition on the rate of polymerization may be eliminated at the high dose rates available from high power accelerators. 25 refs
PLASTIC ANALYSIS OF STEEL FRAME STRUCTURE

Directory of Open Access Journals (Sweden)

M. Rogac

2013-05-01

Full Text Available This paper presents the plastic analysis of steel frame structure loaded by gravity loads. By applying the cinematic theorem of ultimate analysis, the ultimate load for the case of elastic - ideally plastic material is calculated. The identical structure was treated in the computer program SAP2000 where the zone of material reinforcement in the plastic area was covered. Keywords: Steel frame structure, plastic analysis, ultimate gravity load, material reinforcement.
Green Chemistry Metrics with Special Reference to Green Analytical Chemistry

OpenAIRE

Marek Tobiszewski; Mariusz Marć; Agnieszka Gałuszka; Jacek Namieśnik

2015-01-01

The concept of green chemistry is widely recognized in chemical laboratories. To properly measure an environmental impact of chemical processes, dedicated assessment tools are required. This paper summarizes the current state of knowledge in the field of development of green chemistry and green analytical chemistry metrics. The diverse methods used for evaluation of the greenness of organic synthesis, such as eco-footprint, E-Factor, EATOS, and Eco-Scale are described. Both the well-establis...
Water Vapor Permeation in Plastics

Energy Technology Data Exchange (ETDEWEB)

Keller, Paul E. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Kouzes, Richard T. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

2017-01-01

Polyvinyl toluene (PVT) and polystyrene (PS) (referred to as “plastic scintillator”) are used for gamma ray detectors. A significant decrease in radiation detection performance has been observed in some PVT-based gamma-ray detectors in systems in outdoor environments as they age. Recent studies have revealed that plastic scintillator can undergo an environmentally related material degradation that adversely affects gamma ray detection performance under certain conditions and histories. A significant decrease in sensitivity has been seen in some gamma-ray detectors in some systems as they age. The degradation of sensitivity of plastic scintillator over time is due to a variety of factors, and the term “aging” is used to encompass all factors. Some plastic scintillator samples show no aging effects (no significant change in sensitivity over more than 10 years), while others show severe aging (significant change in sensitivity in less than 5 years). Aging effects arise from weather (variations in heat and humidity), chemical exposure, mechanical stress, light exposure, and loss of volatile components. The damage produced by these various causes can be cumulative, causing observable damage to increase over time. Damage may be reversible up to some point, but becomes permanent under some conditions. The objective of this report is to document the phenomenon of permeability of plastic scintillator to water vapor and to derive the relationship between time, temperature, humidity and degree of water penetration in plastic. Several conclusions are documented about the properties of water permeability of plastic scintillator.

The plasticity of clays

Science.gov (United States)

Group, F.F.

1905-01-01

(1) Sand injures plasticity little at first because the grains are suspended in a plastic mass. It is only when grains are abundant enough to come in contact with their neighbors, that the effect becomes serious, and then both strength and amount of possible flow are injured. (2) Certain rare organic colloids increase the plasticity by rendering the water viscous. (3) Fineness also tends to increase plasticity. (4) Plane surfaces (plates) increase the amount of possible flow. They also give a chance for lubrication by thinner films, thus increasing the friction of film, and the strength of the whole mass. The action of plates is thus twofold ; but fineness may be carried to such an extent as to break up plate-like grains into angular fragments. The beneficial effects of plates are also decreased by the fact that each is so closely surrounded by others in the mass. (5) Molecular attraction is twofold in increasing plasticity. As the attraction increases, the coherence and strength of the mass increase, and the amount of possible deformation before crumbling also increases. Fineness increases this action by requiring more water. Colloids and crystalloids in solution may also increase the attraction. It is thus seen to be more active than any other single factor.
Plastic debris in the coastal environment: The invincible threat? Abundance of buried plastic debris on Malaysian beaches.

Science.gov (United States)

Fauziah, S H; Liyana, I A; Agamuthu, P

2015-09-01

Studies on marine debris have gained worldwide attention since many types of debris have found their way into the food chain of higher organisms. Thus, it is crucial that more focus is given to this area in order to curb contaminations in sea food. This study was conducted to quantify plastic debris buried in sand at selected beaches in Malaysia. Marine debris was identified according to size range and distribution, and this information was related to preventive actions to improve marine waste issues. For the purpose of this study, comparison of plastic waste abundance between a recreational beach and fish-landing beaches was also carried out, since the different beach types represent different activities that produce debris. Six beaches along the Malaysian coastline were selected for this study. The plastic types in this study were related to the functions of the beach. While recreational beaches have abundant quantities of plastic film, foamed plastic including polystyrene, and plastic fragment, fish-landing beaches accumulated line and foamed plastic. A total of 2542 pieces (265.30 g m(-2)) of small plastic debris were collected from all six beaches, with the highest number from Kuala Terengganu, at 879 items m(-2) on Seberang Takir Beach, followed by Batu Burok Beach with 780 items m(-2). Findings from studies of Malaysian beaches have provided a clearer understanding of the distribution of plastic debris. This demonstrates that commitments and actions, such as practices of the 'reduce, reuse, recycle' (3R) approach, supporting public awareness programmes and beach clean-up activities, are essential in order to reduce and prevent plastic debris pollution. © The Author(s) 2015.
Review of the partitioning of chemicals into different plastics: Consequences for the risk assessment of marine plastic debris

International Nuclear Information System (INIS)

O'Connor, Isabel A.; Golsteijn, Laura; Hendriks, A. Jan

2016-01-01

Marine plastic debris are found worldwide in oceans and coastal areas. They degrade only slowly and contain chemicals added during manufacture or absorbed from the seawater. Therefore, they can pose a long-lasting contaminant source and potentially transfer chemicals to marine organisms when ingested. In order to assess their risk, the contaminant concentration in the plastics needs to be estimated and differences understood. We collected from literature plastic water partition coefficients of various organic chemicals for seven plastic types: polydimethylsiloxane (PDMS), high-density, low-density and ultra-high molecular weight polyethylene (LDPE, HDPE, UHMWPE), polystyrene (PS), polypropylene (PP), and polyvinyl chloride (PVC). Most data was available for PDMS (1060) and LDPE (220), but much less for the remaining plastics (73). Where possible, regression models were developed and the partitioning was compared between the different plastic types. The partitioning of chemicals follows the order of LDPE ≈ HDPE ≥ PP > PVC ≈ PS. Data describing the impact of weathering are urgently needed. - Highlights: • Comparison of organic chemicals partitioning into seven plastic types • Linear correlation between plastic-water partition coefficient K pw and K ow • More data is needed for polypropylene, polystyrene and polyvinyl chloride. • In all plastic types, most K pw were similar to/smaller than the corresponding K ow .
Plasticity of pressure-sensitive materials

CERN Document Server

Ochsner, Andreas

2014-01-01

Classical plasticity theory of metals is independent of the hydrostatic pressure. However, if the metal contains voids or pores or if the structure is composed of cells, this classical assumption is no more valid and the influence of the hydrostatic pressure must be incorporated in the constitutive description. Looking at the microlevel, metal plasticity is connected with the uniform planes of atoms organized with long-range order. Planes may slip past each other along their close-packed directions. The result is a permanent change of shape within the crystal and plastic deformation. The presence of dislocations increases the likelihood of planes slipping. Nowadays, the theory of pressure sensitive plasticity is successfully applied to many other important classes of materials (polymers, concrete, bones etc.) even if the phenomena on the micro-level are different to classical plasticity of metals. The theoretical background of this phenomenological approach based on observations on the macro-level is describe...
Seabirds, gyres and global trends in plastic pollution

International Nuclear Information System (INIS)

Franeker, Jan A. van; Law, Kara Lavender

2015-01-01

Fulmars are effective biological indicators of the abundance of floating plastic marine debris. Long-term data reveal high plastic abundance in the southern North Sea, gradually decreasing to the north at increasing distance from population centres, with lowest levels in high-arctic waters. Since the 1980s, pre-production plastic pellets in North Sea fulmars have decreased by ∼75%, while user plastics varied without a strong overall change. Similar trends were found in net-collected floating plastic debris in the North Atlantic subtropical gyre, with a ∼75% decrease in plastic pellets and no obvious trend in user plastic. The decreases in pellets suggest that changes in litter input are rapidly visible in the environment not only close to presumed sources, but also far from land. Floating plastic debris is rapidly “lost” from the ocean surface to other as-yet undetermined sinks in the marine environment. - Highlights: • Seabirds are effective biological monitors of floating plastic marine debris. • Plastics in fulmar stomachs and in the North Atlantic gyre show similar trends. • Pre-production plastic pellets show strong decreases in fulmars and in the gyre. • These data show that floating plastics rapidly disappear from the ocean surface. - Long term studies give evidence that reduced input of plastic debris into the ocean becomes rapidly visible. Floating plastics disappear to as-yet undetermined sinks
Plastic zonder olie : lesmodule voor nieuwe scheikunde

OpenAIRE

Langejan, B.; Klein Douwel, C.; Horst, ter, J.J.; Tijdink, K.; Marle, van, N.; Klaasen, P.; Coolen, R.; Assenbergh, van, P.; Sijbers, J.P.J.; Mast, A.

2013-01-01

Lesmodule voor nieuwe scheikunde voor leerlingen uit 5 en 6 vwo. Bioplastics worden gemaakt uit natuurlijke grondstoffen. Als ze de synthetische plastics vervangen kan de voorraad aardolie ontzien worden. Omdat veel bioplastics afbreekbaar zijn, kan ook de berg plastic afval krimpen. Maar zijn bioplastics in staat om ons de reguliere plastics te doen vergeten? Hoe maken we bioplastics met dezelfde veelzijdige eigenschappen als plastic? Waar komen de uiteenlopende eigenschappen van plastics ei...
Elimination of Plastic Polymers in Natural Environments

OpenAIRE

Ramirez-Ekner, Sofia; Bidstrup, Marie Juliane Svea; Brusen, Nicklas Hald; Rugaard-Morgan, Zsa-Zsa Sophie Oona Ophelia

2017-01-01

Plastic production and consumption continues to rise and subsequently plastic waste continues to accumulates in natural environments, causing harm to ecosystems.The aim of this paper was to come up with a way to utilize organisms, that have been identified to produce plastic degrading enzymes, as a waste disposal technology. This review includes accounts of plastic production rates, the occurrence of plastic in natural environments and the current waste management systems to create an underst...
The evolution of age-dependent plasticity

NARCIS (Netherlands)

Fischer, Barbara; van Doorn, G. Sander; Dieckmann, Ulf; Taborsky, Barbara

2014-01-01

When organisms encounter environments that are heterogeneous in time, phenotypic plasticity is often favored by selection. The degree of such plasticity can vary during an organism''s lifetime, but the factors promoting differential plastic responses at different ages or life stages remain poorly
Biodegradability of Plastics: Challenges and Misconceptions.

Science.gov (United States)

Kubowicz, Stephan; Booth, Andy M

2017-11-07

Plastics are one of the most widely used materials and, in most cases, they are designed to have long life times. Thus, plastics contain a complex blend of stabilizers that prevent them from degrading too quickly. Unfortunately, many of the most advantageous properties of plastics such as their chemical, physical and biological inertness and durability present challenges when plastic is released into the environment. Common plastics such as polyethylene (PE), polypropylene (PP), polystyrene (PS), and polyethylene terephthalate (PET) are extremely persistent in the environment, where they undergo very slow fragmentation (projected to take centuries) into small particles through photo-, physical, and biological degradation processes 1 . The fragmentation of the material into increasingly smaller pieces is an unavoidable stage of the degradation process. Ultimately, plastic materials degrade to micron-sized particles (microplastics), which are persistent in the environment and present a potential source of harm for organisms.
Synaptic plasticity in drug reward circuitry.

Science.gov (United States)

Winder, Danny G; Egli, Regula E; Schramm, Nicole L; Matthews, Robert T

2002-11-01

Drug addiction is a major public health issue worldwide. The persistence of drug craving coupled with the known recruitment of learning and memory centers in the brain has led investigators to hypothesize that the alterations in glutamatergic synaptic efficacy brought on by synaptic plasticity may play key roles in the addiction process. Here we review the present literature, examining the properties of synaptic plasticity within drug reward circuitry, and the effects that drugs of abuse have on these forms of plasticity. Interestingly, multiple forms of synaptic plasticity can be induced at glutamatergic synapses within the dorsal striatum, its ventral extension the nucleus accumbens, and the ventral tegmental area, and at least some of these forms of plasticity are regulated by behaviorally meaningful administration of cocaine and/or amphetamine. Thus, the present data suggest that regulation of synaptic plasticity in reward circuits is a tractable candidate mechanism underlying aspects of addiction.
Southern African Business Review - Vol 21, No 1 (2017)

African Journals Online (AJOL)

Southern African Business Review - Vol 21, No 1 (2017) ... Pre-packaged applications in business reorganisations: International principles · EMAIL ... Microcredit supply under Islamic Banking in Khartoum State, Sudan · EMAIL FREE FULL ...
Pregnancy and the Plastic Surgery Resident.

Science.gov (United States)

Garza, Rebecca M; Weston, Jane S; Furnas, Heather J

2017-01-01

Combining pregnancy with plastic surgery residency has historically been difficult. Two decades ago, 36 percent of plastic surgery program directors surveyed actively discouraged pregnancy among residents, and 33 percent of women plastic surgeons suffered from infertility. Most alarmingly, 26 percent of plastic surgery trainees had had an elective abortion during residency. With increasing numbers of women training in plastic surgery, this historical lack of support for pregnancy deserves further attention. To explore the current accommodations made for the pregnant plastic surgery resident, an electronic survey was sent to 88 plastic surgery program directors in the United States. Fifty-four responded, for a response rate of 61.36 percent. On average, a director trained a total of 7.91 women among 17.28 residents trained over 8.19 years. Of the women residents, 1.43 were pregnant during a director's tenure, with 1.35 of those residents taking maternity leave. An average 1.75 male residents took paternity leave. Approximately one-third of programs had a formal maternity/paternity leave policy (36.54 percent) which, in most cases, was limited to defining allowed weeks of leave, time required to fulfill program requirements, and remuneration during leave. This survey of plastic surgery directors is a first step in defining the challenges training programs face in supporting the pregnant resident. Directors provided comments describing their challenges accommodating an absent resident in a small program and complying with the American Board of Plastic Surgery's required weeks of training per year. A discussion of these challenges is followed by suggested solutions.
Journal of Applied Sciences and Environmental Management - Vol ...

African Journals Online (AJOL)

Journal of Applied Sciences and Environmental Management. ... AFRICAN JOURNALS ONLINE (AJOL) · Journals · Advanced Search · USING ... Journal of Applied Sciences and Environmental Management - Vol 22, No 5 (2018) .... Growth Performance of Five Bean (Phaseolus spp) Varieties as Influenced by Organic ...
The New Color of Chemistry: Green Chemistry

OpenAIRE

Zuhal GERÇEK

2012-01-01

Green chemistry which is the new application of chemistry rules provides solutions to problems that mankind is faced with climate changes, sustainable agriculture, energy, toxics, depletion of natural sources e.g. designing new chemicals and processes that production and utilization of hazardous matters. So, it is the indispensible tool for sustainable development. Current and future chemists should consider the human health and ecological issues in their professional life. In order to provid...
Nuclear chemistry in the traditional chemistry program

International Nuclear Information System (INIS)

Kleppinger, E.W.

1993-01-01

The traditional undergraduate program for chemistry majors, especially at institutions devoted solely to undergraduate education, has limited space for 'special topics' courses in areas such as nuclear and radiochemistry. A scheme is proposed whereby the basic topics covered in an introductury radiochemistry course are touched upon, and in some cases covered in detail, at some time during the four-year sequence of courses taken by a chemistry major. (author) 6 refs.; 7 tabs
Functional nanostructures on injection molded plastic

DEFF Research Database (Denmark)

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

Nanotechnology can be used to make inexpensive plastic parts with functional surfaces. The plastic parts can be molded using a standard injection molding process. The nanostructures are directly transferred from the surface of the molding tool to the surface of the molded plastic part during...
7 CFR 58.326 - Plastic cream.

Science.gov (United States)

2010-01-01

... 7 Agriculture 3 2010-01-01 2010-01-01 false Plastic cream. 58.326 Section 58.326 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Standards... Material § 58.326 Plastic cream. To produce plastic cream eligible for official certification, the quality...
Plastics chemistry. Different types of plastics chemical aging

International Nuclear Information System (INIS)

Verdu, J.

2002-01-01

In this work are studied the different types of aging; they are classified according to the external effects at which they are submitted to: high temperature for a thermal aging; UV or ionizing radiations for the photochemical or radiochemical aging; hydrolysis, oxidation, ozonolysis or mechanical stress for the chemical aging; living organisms for the biochemical aging. (O.M.)
Annual report 1986 chemistry department

International Nuclear Information System (INIS)

Funck, J.; Larsen, E.; Nielsen, O.J.

1987-03-01

This report contains a brief survey of the main activities in the Chemistry Department. All articles and reports published and lectures given in 1986 are presented. The facilities and equipment are mentioned briefly. The activities are divided into the following groups: radioisotope chemistry, analytical- and organic chemistry, environmental chemistry, polymer chemistry, radical chemistral, mineral processing, and general. (author)
Environment friendly solutions of plastics waste management

International Nuclear Information System (INIS)

Pirzada, F.N.; Riffat, T.; Pirzada, M.D.S.

1997-01-01

The use of plastics is growing worldwide. Consequently, the volume of plastic waste is also increasing. Presently, more than 100 million tons per year of plastic is being produced globally. In U.S. alone more than 10 million tons of plastic is being dumped in landfills as waste, where it can persist for decades. This has resulted in exhausting old landfills. Public awareness on environment is also making it difficult to find new sites for landfills. This has led to increased emphasis on treatment and recycling of plastic wastes. Volume reduction of plastic waste has some unique problems. They arise from the intrinsic chemical inertness of polymeric materials and toxic nature of their degradation byproducts. The paper reviews the present state of plastic waste management including land filling, incineration and recycling technologies. The technical problems associated with each of these processes have been discussed. There is also brief description of ongoing R and D for finding improved methods of plastic waste handling with their promises and problems. The role of tougher legislation in developing better recycling methods and degradable plastics has also been evaluated. The claims made by the proponents of degradable polymers have also been critically reviewed. (authors)

Moderator Chemistry Program

International Nuclear Information System (INIS)

Dewitt, L.V.; Gibbs, A.; Lambert, D.P.; Bohrer, S.R.; Fanning, R.L.; Houston, M.W.; Stinson, S.L.; Deible, R.W.; Abdel-Khalik, S.I.

1990-11-01

Over the past fifteen months, the Systems Chemistry Group of the Reactor Engineering Department has undertaken a comprehensive study of the Department's moderator chemistry program at Savannah River Site (SRS). An internal review was developed to formalize and document this program. Objectives were as outlined in a mission statement and action plan. In addition to the mission statement and action plan, nine separate task reports have been issued during the course of this study. Each of these task reports is included in this document as a chapter. This document is an organized compilation of the individual reports issued by the Systems Chemistry Group in assessment of SRS moderator chemistry to determine if there were significant gaps in the program as ft existed in October, 1989. While these reviews found no significant gaps in that mode of operation, or any items that adversely affected safety, items were identified that could be improved. Many of the items have already been dear with or are in the process of completion under this Moderator Chemistry Program and other Reactor Restart programs. A complete list of the items of improvement found under this assessment is found in Chapter 9, along with a proposed time table for correcting remaining items that can be improved for the chemistry program of SRS reactors. An additional external review of the moderator chemistry processes, recommendations, and responses to/from the Reactor Corrosion Mitigation Committee is included as Appendix to this compilation
Publicising chemistry in a multicultural society through chemistry outreach

Directory of Open Access Journals (Sweden)

Joyce D. Sewry

2011-11-01

Full Text Available Given the emphasis in Higher Education on community engagement in South Africa and the importance of international collaboration, we discuss a joint approach to chemistry outreach in two countries on two continents with widely differing target school audiences. We describe the history of the partnership between the chemistry departments at Rhodes University and the University of Bristol and provide an outline of the chemistry content of their outreach initiatives, the modes of delivery, the advantages to both departments and their students for involvement in various levels of outreach, the challenges they still face and additional opportunities that such work facilitated. The lecture demonstration ‘A Pollutant’s Tale’ was presented to thousands of learners all over the world, including learners at resource-deprived schools in South Africa. Challenges to extend outreach activities in South Africa include long travelling distances, as well as a lack of facilities (such as school halls and electricity at schools. Outreach activities not only impacted on the target audience of young learners, they also impacted upon the postgraduate and other chemistry students taking part in these initiatives. This collaboration strengthened both institutions and their outreach work and may also lead to chemistry research collaborations between the academics involved.
AJESMS_ Vol 8 2010 August 15 2011

African Journals Online (AJOL)

Prof. Mereku

2010-08-15

Aug 15, 2010 ... African Journal of Educational Studies in Mathematics and Sciences Vol. ... girls from two Senior High Schools in Accra, the capital of Ghana in West Africa. .... On the face of it, the Brazilian and Swedish children might seem to have the ... The two profile dimensions that have been specified for teaching, ...
SAMJ

African Journals Online (AJOL)

Rotman. Pp. xxiv + 481. NLG480/US$245. Amsterdam: Elsevier. Science. 1998. ISBN 0-444-82608-4. New Trends ... Advances in Neutron Capture. Vol. I: Medicine and Physics. Vol. JI : Chemistry and Biology. * Edited by Borje Larsson, John.
Modeling plasticity by non-continuous deformation

Science.gov (United States)

Ben-Shmuel, Yaron; Altus, Eli

2017-10-01

Plasticity and failure theories are still subjects of intense research. Engineering constitutive models on the macroscale which are based on micro characteristics are very much in need. This study is motivated by the observation that continuum assumptions in plasticity in which neighbour material elements are inseparable at all-time are physically impossible, since local detachments, slips and neighbour switching must operate, i.e. non-continuous deformation. Material microstructure is modelled herein by a set of point elements (particles) interacting with their neighbours. Each particle can detach from and/or attach with its neighbours during deformation. Simulations on two- dimensional configurations subjected to uniaxial compression cycle are conducted. Stochastic heterogeneity is controlled by a single "disorder" parameter. It was found that (a) macro response resembles typical elasto-plastic behaviour; (b) plastic energy is proportional to the number of detachments; (c) residual plastic strain is proportional to the number of attachments, and (d) volume is preserved, which is consistent with macro plastic deformation. Rigid body displacements of local groups of elements are also observed. Higher disorder decreases the macro elastic moduli and increases plastic energy. Evolution of anisotropic effects is obtained with no additional parameters.
Plastic debris in the open ocean

KAUST Repository

Cozar, Andres

2014-06-30

There is a rising concern regarding the accumulation of floating plastic debris in the open ocean. However, the magnitude and the fate of this pollution are still open questions. Using data from the Malaspina 2010 circumnavigation, regional surveys, and previously published reports, we show a worldwide distribution of plastic on the surface of the open ocean, mostly accumulating in the convergence zones of each of the five subtropical gyres with comparable density. However, the global load of plastic on the open ocean surface was estimated to be on the order of tens of thousands of tons, far less than expected. Our observations of the size distribution of floating plastic debris point at important size-selective sinks removing millimeter-sized fragments of floating plastic on a large scale. This sink may involve a combination of fast nano-fragmentation of the microplastic into particles of microns or smaller, their transference to the ocean interior by food webs and ballasting processes, and processes yet to be discovered. Resolving the fate of the missing plastic debris is of fundamental importance to determine the nature and significance of the impacts of plastic pollution in the ocean.
Plastic debris in the open ocean.

Science.gov (United States)

Cózar, Andrés; Echevarría, Fidel; González-Gordillo, J Ignacio; Irigoien, Xabier; Ubeda, Bárbara; Hernández-León, Santiago; Palma, Alvaro T; Navarro, Sandra; García-de-Lomas, Juan; Ruiz, Andrea; Fernández-de-Puelles, María L; Duarte, Carlos M

2014-07-15

There is a rising concern regarding the accumulation of floating plastic debris in the open ocean. However, the magnitude and the fate of this pollution are still open questions. Using data from the Malaspina 2010 circumnavigation, regional surveys, and previously published reports, we show a worldwide distribution of plastic on the surface of the open ocean, mostly accumulating in the convergence zones of each of the five subtropical gyres with comparable density. However, the global load of plastic on the open ocean surface was estimated to be on the order of tens of thousands of tons, far less than expected. Our observations of the size distribution of floating plastic debris point at important size-selective sinks removing millimeter-sized fragments of floating plastic on a large scale. This sink may involve a combination of fast nano-fragmentation of the microplastic into particles of microns or smaller, their transference to the ocean interior by food webs and ballasting processes, and processes yet to be discovered. Resolving the fate of the missing plastic debris is of fundamental importance to determine the nature and significance of the impacts of plastic pollution in the ocean.
Plastic debris in the open ocean

Science.gov (United States)

Cózar, Andrés; Echevarría, Fidel; González-Gordillo, J. Ignacio; Irigoien, Xabier; Úbeda, Bárbara; Hernández-León, Santiago; Palma, Álvaro T.; Navarro, Sandra; García-de-Lomas, Juan; Ruiz, Andrea; Fernández-de-Puelles, María L.; Duarte, Carlos M.

2014-01-01

There is a rising concern regarding the accumulation of floating plastic debris in the open ocean. However, the magnitude and the fate of this pollution are still open questions. Using data from the Malaspina 2010 circumnavigation, regional surveys, and previously published reports, we show a worldwide distribution of plastic on the surface of the open ocean, mostly accumulating in the convergence zones of each of the five subtropical gyres with comparable density. However, the global load of plastic on the open ocean surface was estimated to be on the order of tens of thousands of tons, far less than expected. Our observations of the size distribution of floating plastic debris point at important size-selective sinks removing millimeter-sized fragments of floating plastic on a large scale. This sink may involve a combination of fast nano-fragmentation of the microplastic into particles of microns or smaller, their transference to the ocean interior by food webs and ballasting processes, and processes yet to be discovered. Resolving the fate of the missing plastic debris is of fundamental importance to determine the nature and significance of the impacts of plastic pollution in the ocean. PMID:24982135
Wind tunnel evaluation of Hi-Vol TSP effectiveness data

Data.gov (United States)

U.S. Environmental Protection Agency — Wind tunnel evaluation of EPA's Hi-Vol TSP sampler for sampling effectiveness with regards to aerodynamic particle diameter (5 to 35 microns), wind speed (2, 8, 24...
Plastic Accumulation in the Mediterranean Sea

OpenAIRE

C?zar, Andr?s; Sanz-Mart?n, Marina; Mart?, Elisa; Gonz?lez-Gordillo, J. Ignacio; Ubeda, B?rbara; G?lvez, Jos? ?.; Irigoien, Xabier; Duarte, Carlos M.

2015-01-01

Copyright: © 2015 Cózar et al. Concentrations of floating plastic were measured throughout the Mediterranean Sea to assess whether this basin can be regarded as a great accumulation region of plastic debris. We found that the average density of plastic (1 item per 4 m2), as well as its frequency of occurrence (100% of the sites sampled), are comparable to the accumulation zones described for the five subtropical ocean gyres. Plastic debris in the Mediterranean surface waters was dominated by ...
21 CFR 872.5470 - Orthodontic plastic bracket.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Orthodontic plastic bracket. 872.5470 Section 872...) MEDICAL DEVICES DENTAL DEVICES Therapeutic Devices § 872.5470 Orthodontic plastic bracket. (a) Identification. An orthodontic plastic bracket is a plastic device intended to be bonded to a tooth to apply...
Plastic photochromic eyewear: a status report

Science.gov (United States)

Crano, John C.; Elias, Richard C.

1991-12-01

An estimated 10 million pairs of photochromic prescription lenses were dispensed in the United States in 1989, essentially all based on a silver halide system suspended in an inorganic glass. A significant trend within the ophthalmic industry has been the growth of light-weight plastic lenses. In the United States market, the percentage of prescription eyewear made of plastic is now greater than 70%. With this increasing market penetration of plastic lenses, the desire for an acceptable plastic photochromic lens has also increased. As with any commercial product, in order to achieve consumer acceptance there exist several technical requirements for a plastic photochromic lens. These include the light transmission and color of the lens in both the unactivated and activated states, the speeds of darkening and fading, and the fatigue resistance or lifetime of the photochromic system. These requirements will be defined along with approaches to achieving them. The properties of the commercially available plastic photochromic lenses will be compared with the defined requirements.
American Association for Clinical Chemistry

Science.gov (United States)

... Find the answer to your question IN CLINICAL CHEMISTRY Hs-cTnI as a Gatekeeper for Further Cardiac ... Online Harmonization.net Commission on Accreditation in Clinical Chemistry American Board of Clinical Chemistry Clinical Chemistry Trainee ...
Proceedings of the 17. Annual Meeting of the Brazilian Chemistry Society; 7. National Symposium on Inorganic Chemistry. Abstracts

International Nuclear Information System (INIS)

1994-01-01

These 17. Annual Meeting of the Brazilian Chemistry Society and 7. National Symposium on Inorganic Chemistry present several subjects of different interests for the participants, including sections about inorganic chemistry; organic chemistry; environmental chemistry; technological chemistry; electrochemistry; physical chemistry; photochemistry; chemical education; natural products; analytical chemistry and biological chemistry. (C.G.C.)
Annual report 1988 Chemistry Department

International Nuclear Information System (INIS)

Funck, J.; Neve Larsen, Aa.; Larsen, E.; Nielsen, O.J.

1989-05-01

This report contains a brief survey of the main activities in the Chemistry Department. The names and abstracts of all articles and reports published and lectures given in 1988 are presented. The facilities and equipment are mentioned briefly. The activities are divided into the following groups: radioisotope chemistry, analytical- and organic chemistry, environmental chemistry, polymer chemistry, chemical reactivity, mineral processing, and general. (author)
Annual report 1989 Chemistry Department

International Nuclear Information System (INIS)

Funck, J.; Neve Larsen, Aa.; Larsen, E.; Nielsen, O.J.

1990-03-01

This report contains a brief survey of the main activities in the Chemistry Department. The names and abstracts of all articles and reports published and lectures given in 1989 are presented. The facilities and equipment are mentioned briefly. The activities are divided into the following groups: radioisotope chemistry, analytical- and organic chemistry, environmental chemistry, polymer chemistry, chemical reactivity, mineral processing, and general. (author)
Why Teach Environmental Chemistry?

Science.gov (United States)

Gardner, Marjorie H.

1974-01-01

Discusses the importance of teaching environmental chemistry in secondary school science classes, and outlines five examples of environmental chemistry problems that focus on major concepts of chemistry and have critical implications for human survival and well-being. (JR)
49 CFR 192.375 - Service lines: Plastic.

Science.gov (United States)

2010-10-01

... 49 Transportation 3 2010-10-01 2010-10-01 false Service lines: Plastic. 192.375 Section 192.375... § 192.375 Service lines: Plastic. (a) Each plastic service line outside a building must be installed... terminate above ground level and outside the building, if— (i) The above ground level part of the plastic...
[From the French Society of Plastic and Reconstructive Surgery to the French Society of Plastic Reconstructive and Aesthetic Surgery].

Science.gov (United States)

Glicenstein, J

2004-04-01

(The) 3rd December 1952, 11 surgeons and other specialists found the French Society of Plastic and Reconstructive Surgery (SFCPR) which was officially published on (the) 28 September 1953. The first congress was during October 1953 and the first president as Maurice Aubry. The first secretary was Daniel Morel Fatio. The symposiums were after about three of four times each year and the thematic subjects were initially according the reconstructive surgery. The review "Annales de chirurgie plastique" was free in 1956. The members of the Society were about 30 initially, but their plastic surgery in the big hospitals at Paris and other big towns in France. The "specialty" of plastic surgery was created in 1971. On "syndicate", one French board of plastic reconstructive and aesthetic surgery, the increasing of departments of plastic surgery were the front of increasing of the plastic surgery in French and of the number of the French Society of Plastic Reconstructive surgery (580 in 2003). The French Society organized the International Congress of Plastic Surgery in 1975. The society SFCPR became the French Society of plastic reconstruction and Aesthetic Surgery (SFCPRE) in 1983 and the "logo" (front view) was in the 1994 SOF.CPRE.
Journal of Applied Sciences and Environmental Management - Vol ...

African Journals Online (AJOL)

Journal of Applied Sciences and Environmental Management. ... AFRICAN JOURNALS ONLINE (AJOL) · Journals · Advanced Search · USING ... Journal of Applied Sciences and Environmental Management - Vol 22, No 4 (2018) ... Evaluating the effect of mobility speed on the performance of three handover algorithms in ...

Shostakovich: The Orchestral Songs Vol. 2 / Michael Tanner

Index Scriptorium Estoniae

Tanner, Michael

1996-01-01

Uuest heliplaadist "Shostakovich: The Orchestral Songs Vol. 2: Six Romances on texts by Japanese poets, Op. 21. Six Poems on Marina Tsvetayeva, Op. 143. Suite on Verses of Michelangelo, Op. 145. Gothenburg Symphony Orchestra, Neeme Järvi". DG 447 085-2GH (71 minutes:DDD)
Frontiers in Gold Chemistry

OpenAIRE

Ahmed A. Mohamed

2015-01-01

Basic chemistry of gold tells us that it can bond to sulfur, phosphorous, nitrogen, and oxygen donor ligands. The Frontiers in Gold Chemistry Special Issue covers gold complexes bonded to the different donors and their fascinating applications. This issue covers both basic chemistry studies of gold complexes and their contemporary applications in medicine, materials chemistry, and optical sensors. There is a strong belief that aurophilicity plays a major role in the unending applications of g...
Advanced Chemistry Laboratory

Data.gov (United States)

Federal Laboratory Consortium — Description/History: Chemistry laboratoryThe Advanced Chemistry Laboratory (ACL) is a unique facility designed for working with the most super toxic compounds known...
Introducing Chemistry Students to the "Real World" of Chemistry

Science.gov (United States)

Brown, Michael E.; Cosser, Ronald C.; Davies-Coleman, Michael T.; Kaye, Perry T.; Klein, Rosalyn; Lamprecht, Emmanuel; Lobb, Kevin; Nyokong, Tebello; Sewry, Joyce D.; Tshentu, Zenixole R.; van der Zeyde, Tino; Watkins, Gareth M.

2010-01-01

A majority of chemistry graduates seek employment in a rapidly changing chemical industry. Our attempts to provide the graduates with skills in entrepreneurship and the ability to understand and communicate with their chemical engineering colleagues, in addition to their fundamental knowledge of chemistry, are described. This is done at…
Plastic ingestion by Flesh-footed Shearwaters (Puffinus carneipes): Implications for fledgling body condition and the accumulation of plastic-derived chemicals

International Nuclear Information System (INIS)

Lavers, Jennifer L.; Bond, Alexander L.; Hutton, Ian

2014-01-01

To provide much needed quantitative data on the lethal and sublethal effects of plastic pollution on marine wildlife, we sampled breast feathers and stomach contents from Flesh-footed Shearwater (Puffinus carneipes) fledglings in eastern Australia. Birds with high levels of ingested plastic exhibited reduced body condition and increased contaminant load (p < 0.05). More than 60% of fledglings exceed international targets for plastic ingestion by seabirds, with 16% of fledglings failing these targets after a single feeding (range: 0.13–3.21 g of plastic/feeding). As top predators, seabirds are considered sentinels of the marine environment. The amount of plastic ingested and corresponding damage to Flesh-footed Shearwater fledglings is the highest reported for any marine vertebrate, suggesting the condition of the Australian marine environment is poor. These findings help explain the ongoing decline of this species and are worrying in light of increasing levels of plastic pollution in our oceans. - Highlights: • Proportion of the shearwater population ingesting plastic increased over four years. • Shearwater body condition is negatively influenced by the amount of ingested plastic. • Shearwater contaminant load is positively related to the amount of ingested plastic. • Many chicks exceed international targets for ingested plastic after a single feeding. • Plastic ingestion in this study is the highest reported for any marine vertebrate. - Flesh-footed Shearwaters ingest large quantities of marine plastic, which is correlated with poor body condition and increased concentrations of trace metals such as chromium
Effect of waste plastic as modifier on thermal stability and degradation kinetics of bitumen/waste plastics blend

Energy Technology Data Exchange (ETDEWEB)

Naskar, M. [Rubber Technology Centre, Indian Institute of Technology, Kharagpur, West Bengal 721302 (India); Chaki, T.K., E-mail: tapan@rtc.iitkgp.ernet.in [Rubber Technology Centre, Indian Institute of Technology, Kharagpur, West Bengal 721302 (India); Reddy, K.S. [Department of Civil Engineering, Indian Institute of Technology, Kharagpur, West Bengal 721302 (India)

2010-09-20

Different modified bituminous binders are used in pavement construction for improved durability and for enhanced performance in resisting cracking and permanent deformation of bituminous layers. Waste plastics, whose disposal is a matter of concern, have been used successfully for modifying bitumen. This paper reports the thermogravimetric studies conducted on waste plastic modified bituminous binders. Modified bituminous binders prepared using different plastic contents (0-7 wt% by weight of bitumen) were investigated. The activation energies were determined from thermogravimetric analysis (TGA) data using Kissinger and the Flynn-Wall-Ozawa methods, which do not require knowledge of the reaction mechanism. Modified bitumen (WPMB5) with 5 wt% plastic was found to have the highest thermal stability compared to other binders investigated. Differential scanning calorimetry (DSC) studies were carried out to find crystalline melting temperature and fusion enthalpy. Rheological parameters of modified binders prepared with different plastic contents also suggest that the 5 wt% plastic content is expected to yield optimal performance.
Effect of waste plastic as modifier on thermal stability and degradation kinetics of bitumen/waste plastics blend

International Nuclear Information System (INIS)

Naskar, M.; Chaki, T.K.; Reddy, K.S.

2010-01-01

Different modified bituminous binders are used in pavement construction for improved durability and for enhanced performance in resisting cracking and permanent deformation of bituminous layers. Waste plastics, whose disposal is a matter of concern, have been used successfully for modifying bitumen. This paper reports the thermogravimetric studies conducted on waste plastic modified bituminous binders. Modified bituminous binders prepared using different plastic contents (0-7 wt% by weight of bitumen) were investigated. The activation energies were determined from thermogravimetric analysis (TGA) data using Kissinger and the Flynn-Wall-Ozawa methods, which do not require knowledge of the reaction mechanism. Modified bitumen (WPMB5) with 5 wt% plastic was found to have the highest thermal stability compared to other binders investigated. Differential scanning calorimetry (DSC) studies were carried out to find crystalline melting temperature and fusion enthalpy. Rheological parameters of modified binders prepared with different plastic contents also suggest that the 5 wt% plastic content is expected to yield optimal performance.
African Journal of Biotechnology - Vol 14, No 18 (2015)

African Journals Online (AJOL)

African Journal of Biotechnology - Vol 14, No 18 (2015). Journal Home ... Isolation of microalgae species from arid environments and evaluation of their potentials for biodiesel production · EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT
Jolivet: Complete Flute Music, Vol. 2 / Guy S. Rickards

Index Scriptorium Estoniae

Rickards, Guy S.

1996-01-01

Uuest heliplaadist "Jolivet: Complete Flute Music, Vol. 2. Kroumata Percussion Ensemble, Tapiola Sinfonietta, Paavo Järvi". BIS CD 739 (64 minutes: DDD). Item marked from CD630 (6/94), CD272, remainder new to UK
In-Package Chemistry Abstraction

Energy Technology Data Exchange (ETDEWEB)

P.S. Domski

2003-07-21

The work associated with the development of this model report was performed in accordance with the requirements established in ''Technical Work Plan for Waste Form Degradation Modeling, Testing, and Analyses in Support of SR and LA'' (BSC 2002a). The in-package chemistry model and in-package chemistry model abstraction are developed to predict the bulk chemistry inside of a failed waste package and to provide simplified expressions of that chemistry. The purpose of this work is to provide the abstraction model to the Performance Assessment Project and the Waste Form Department for development of geochemical models of the waste package interior. The scope of this model report is to describe the development and validation of the in-package chemistry model and in-package chemistry model abstraction. The in-package chemistry model will consider chemical interactions of water with the waste package materials and the waste form for commercial spent nuclear fuel (CSNF) and codisposed high-level waste glass (HLWG) and N Reactor spent fuel (CDNR). The in-package chemistry model includes two sub-models, the first a water vapor condensation (WVC) model, where water enters a waste package as vapor and forms a film on the waste package components with subsequent film reactions with the waste package materials and waste form--this is a no-flow model, the reacted fluids do not exit the waste package via advection. The second sub-model of the in-package chemistry model is the seepage dripping model (SDM), where water, water that may have seeped into the repository from the surrounding rock, enters a failed waste package and reacts with the waste package components and waste form, and then exits the waste package with no accumulation of reacted water in the waste package. Both of the submodels of the in-package chemistry model are film models in contrast to past in-package chemistry models where all of the waste package pore space was filled with water. The
In-Package Chemistry Abstraction

International Nuclear Information System (INIS)

P.S. Domski

2003-01-01

The work associated with the development of this model report was performed in accordance with the requirements established in ''Technical Work Plan for Waste Form Degradation Modeling, Testing, and Analyses in Support of SR and LA'' (BSC 2002a). The in-package chemistry model and in-package chemistry model abstraction are developed to predict the bulk chemistry inside of a failed waste package and to provide simplified expressions of that chemistry. The purpose of this work is to provide the abstraction model to the Performance Assessment Project and the Waste Form Department for development of geochemical models of the waste package interior. The scope of this model report is to describe the development and validation of the in-package chemistry model and in-package chemistry model abstraction. The in-package chemistry model will consider chemical interactions of water with the waste package materials and the waste form for commercial spent nuclear fuel (CSNF) and codisposed high-level waste glass (HLWG) and N Reactor spent fuel (CDNR). The in-package chemistry model includes two sub-models, the first a water vapor condensation (WVC) model, where water enters a waste package as vapor and forms a film on the waste package components with subsequent film reactions with the waste package materials and waste form--this is a no-flow model, the reacted fluids do not exit the waste package via advection. The second sub-model of the in-package chemistry model is the seepage dripping model (SDM), where water, water that may have seeped into the repository from the surrounding rock, enters a failed waste package and reacts with the waste package components and waste form, and then exits the waste package with no accumulation of reacted water in the waste package. Both of the submodels of the in-package chemistry model are film models in contrast to past in-package chemistry models where all of the waste package pore space was filled with water. The current in
Neuronal cytoskeleton in synaptic plasticity and regeneration.

Science.gov (United States)

Gordon-Weeks, Phillip R; Fournier, Alyson E

2014-04-01

During development, dynamic changes in the axonal growth cone and dendrite are necessary for exploratory movements underlying initial axo-dendritic contact and ultimately the formation of a functional synapse. In the adult central nervous system, an impressive degree of plasticity is retained through morphological and molecular rearrangements in the pre- and post-synaptic compartments that underlie the strengthening or weakening of synaptic pathways. Plasticity is regulated by the interplay of permissive and inhibitory extracellular cues, which signal through receptors at the synapse to regulate the closure of critical periods of developmental plasticity as well as by acute changes in plasticity in response to experience and activity in the adult. The molecular underpinnings of synaptic plasticity are actively studied and it is clear that the cytoskeleton is a key substrate for many cues that affect plasticity. Many of the cues that restrict synaptic plasticity exhibit residual activity in the injured adult CNS and restrict regenerative growth by targeting the cytoskeleton. Here, we review some of the latest insights into how cytoskeletal remodeling affects neuronal plasticity and discuss how the cytoskeleton is being targeted in an effort to promote plasticity and repair following traumatic injury in the central nervous system. © 2013 International Society for Neurochemistry.
Mechanisms of GABAergic Homeostatic Plasticity

Directory of Open Access Journals (Sweden)

Peter Wenner

2011-01-01

Full Text Available Homeostatic plasticity ensures that appropriate levels of activity are maintained through compensatory adjustments in synaptic strength and cellular excitability. For instance, excitatory glutamatergic synapses are strengthened following activity blockade and weakened following increases in spiking activity. This form of plasticity has been described in a wide array of networks at several different stages of development, but most work and reviews have focussed on the excitatory inputs of excitatory neurons. Here we review homeostatic plasticity of GABAergic neurons and their synaptic connections. We propose a simplistic model for homeostatic plasticity of GABAergic components of the circuitry (GABAergic synapses onto excitatory neurons, excitatory connections onto GABAergic neurons, cellular excitability of GABAergic neurons: following chronic activity blockade there is a weakening of GABAergic inhibition, and following chronic increases in network activity there is a strengthening of GABAergic inhibition. Previous work on GABAergic homeostatic plasticity supports certain aspects of the model, but it is clear that the model cannot fully account for some results which do not appear to fit any simplistic rule. We consider potential reasons for these discrepancies.
Plasticity characteristic obtained by indentation

International Nuclear Information System (INIS)

Milman, Yu V

2008-01-01

A dimensionless parameter δ H = ε p /ε t (where ε p and ε t are the average values of plastic and total deformation of material on the contact area indenter-specimen) may be used as the plasticity characteristic of materials, which made it possible to characterize the plasticity of materials that are brittle in standard mechanical tests. δ H may be calculated from the values of microhardness HM, Young's modulus E and Poisson's ratio ν. In instrumented indentation the plasticity characteristic δ A = A p /A t (A p and A t are the work of plastic and total deformation during indentation) may be calculated. δ A ∼ δ H for materials with δ H > 0.5, i.e. for all metals and the majority of ceramic materials. In this case, the theoretical equation δ A ∼ δ H = 1-10.2 · (1 - ν - 2ν 2 )(HM/E) is satisfied in experiments with the Berkovich indenter. The influence of the temperature and structural parameters (dislocation density and grain size including nanostructured materials) on δ H is discussed
Smartphones and the plastic surgeon.

Science.gov (United States)

Al-Hadithy, Nada; Ghosh, Sudip

2013-06-01

Surgical trainees are facing limited training opportunities since the introduction of the European Working Time Directive. Smartphone sales are increasing and have usurped computer sales for the first time. In this context, smartphones are an important portable reference and educational tool, already in the possession of the majority of surgeons in training. Technology in the palm of our hands has led to a revolution of accessible information for the plastic surgery trainee and surgeon. This article reviews the uses of smartphones and applications for plastic surgeons in education, telemedicine and global health. A comprehensive guide to existing and upcoming learning materials and clinical tools for the plastic surgeon is included. E-books, podcasts, educational videos, guidelines, work-based assessment tools and online logbooks are presented. In the limited resource setting of modern clinical practice, savvy plastic surgeons can select technological tools to democratise access to education and best clinical care. Copyright © 2013 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.
A Quantum Chemistry Concept Inventory for Physical Chemistry Classes

Science.gov (United States)

Dick-Perez, Marilu; Luxford, Cynthia J.; Windus, Theresa L.; Holme, Thomas

2016-01-01

A 14-item, multiple-choice diagnostic assessment tool, the quantum chemistry concept inventory or QCCI, is presented. Items were developed based on published student misconceptions and content coverage and then piloted and used in advanced physical chemistry undergraduate courses. In addition to the instrument itself, data from both a pretest,…
Annual report 1983 Chemistry Department

International Nuclear Information System (INIS)

Funck, J.; Larsen, E.; Nielsen, O.J.

1984-05-01

This report contains a brief survey of the main activities in the Chemistry Department. All articles and reports published and lectures given in 1983 are presented. The facilities and equipment are barely mentioned. The activities are divided into nine groups: 1. radioisotope chemistry 2. analytical- and organic chemistry 3. environmental chemistry 4. polymer chemistry 5. geochemistry and waste disposal 6. radical chemstry 7. positron annihilation 8. mineral processing 9. general. (author)
African Journal of Clinical and Experimental Microbiology - Vol 5, No ...

African Journals Online (AJOL)

African Journal of Clinical and Experimental Microbiology - Vol 5, No 1 (2004) ... ASYMPTOMATIC SIGNIFICANT BACTERIURIA AMONG PREGNANT WOMEN IN ... TO PARASITISM AND THE IMPLICATION ON TREATMENT APPROACH ...
Smart film actuators using biomass plastic

International Nuclear Information System (INIS)

Yoneyama, Satoshi; Tanaka, Nobuo

2011-01-01

This paper presents a novel smart film actuator based on the use of a biomass plastic as a piezoelectric film. Conventional polymeric smart sensors and actuators have been based upon synthetic piezoelectric polymer films such as PVDF. Almost all synthetic polymers are made from nearly depleted oil resources. In addition combustion of their materials releases carbon dioxide, thereby contributing to global warming. Thus at least two important sustainability principles are violated when employing synthetic polymers: avoiding depletable resources and avoiding ecosystem destruction. To overcome such problems, industrial plastic products made from synthetic polymers were developed to replace oil-based plastics with biomass plastics. This paper applies a biomass plastic with piezoelectricity such as poly-L-lactic acid (PLLA). As a result, PLLA film becomes a distributed parameter actuator per se, hence an environmentally conscious smart film actuator is developed. Firstly, this paper overviews the fundamental properties of piezoelectric synthetic polymers and biopolymers. The concept of carbon neutrality using biopolymers is mentioned. Then a two-dimensional modal actuator for exciting a specific structural mode is proposed. Furthermore, a biomass plastic-based cantilever beam with the capability of modal actuation is developed, the validity of the proposed smart film actuator based upon a biomass plastic being analytically as well as experimentally verified
Fundamentals of reactor chemistry

International Nuclear Information System (INIS)

Akatsu, Eiko

1981-12-01

In the Nuclear Engineering School of JAERI, many courses are presented for the people working in and around the nuclear reactors. The curricula of the courses contain also the subject material of chemistry. With reference to the foreign curricula, a plan of educational subject material of chemistry in the Nuclear Engineering School of JAERI was considered, and the fundamental part of reactor chemistry was reviewed in this report. Since the students of the Nuclear Engineering School are not chemists, the knowledge necessary in and around the nuclear reactors was emphasized in order to familiarize the students with the reactor chemistry. The teaching experience of the fundamentals of reactor chemistry is also given. (author)

Perception and acceptance of technological risks. Vol. 3

Energy Technology Data Exchange (ETDEWEB)

Renn, O

1981-01-01

Vol. 3 discusses the problem of attitudes towards nuclear power. Data are compiled for five communities in North-Rhine Westphalia with nuclear facilities and the control community of Kerpen, which has no nuclear power plant. At the same time, the empirical and theoretical investigations are comprehensively evaluated.
Southern African Journal of Environmental Education - Vol 8 (1988)

African Journals Online (AJOL)

Southern African Journal of Environmental Education - Vol 8 (1988) ... An interaction of archaeology with school history in a museum education context ... The child in the outdoor classroom · EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT
Research in Hospitality Management - Vol 5, No 2 (2015)

African Journals Online (AJOL)

Research in Hospitality Management - Vol 5, No 2 (2015) ... Hotel quality in the European Capital of Culture: Leeuwarden 2018 · EMAIL FREE FULL ... Consumer patronage and willingness-to-pay at different levels of restaurant attributes: A ...
Development on the High-throughput Vol-oxidizer for Decladding and Voloxidation of Spent Fuel Rod-cuts

International Nuclear Information System (INIS)

Kim, Young Hwang; Jung, Jae Hoo; Kim, Ki Ho; Park, Byung Buk; Lee, Hyo Jik; Kim, Sung Hyun; Park, Hee Sung; Lee, Jong Kwang; Kim, Ho Dong

2009-12-01

A high-throughput vol-oxidizer which can handle a several ten kg HM/batch is being developed to supply U 3 O 8 powders to an electrolytic reduction reactor in pyro-processing. At the first year step(2007), for enhancement of oxidation and recovery rate, we analyzed the mechanical and chemical methods, and devised the main mechanism with ball drop methods and rotary kiln type. Also, the main devices for oxidation and recovery of rod-cuts were designed by using the Solid Works and COSMOS program tools, and manufactured after thermal/mechanical analysis. In order to verify the main devices, simulation fuels(W 90%+SiO 2 10%) were manufactured and the main devices were tested for the oxidation and recovery rate of its. Here the expansion ratio of simulation fuel is similar to U 3 O 8 (2.7). At the second year step(2008), with the constant ration of rod-cuts volume and expansion ratio of U 3 O 8 (2.7), we produced a theoretical equation that can estimate the volume of rod-cuts according to a variation of their weight and lengths. We considered various materials such as ceramics and Ni-Cr, finally, the APM material which can constantly maintain against high temperature(1,200 .deg. C) and vacuum(1 torr) was selected and a vol-oxidizer was designed. At the third year step(2009), in order to manufacture a high-throughput vol-oxidizer, we have analyzed the vol-oxidizer for remote operability and maintainability, also the remote assembling and disassembling possibilities of the selected modules have been analyzed in terms of visibility, interference, approach, weight, and so on. We have presented final modular design and manufactured a high-throughput vol-oxidizer. Also, we have conducted the blank, heating(over 500 .deg. C) and hull separation test(capacity : 50 kg HM/batch, hull length 50mm) on the high-throughput vol-oxidizer. Also, these design technologies for the high-throughput vol-oxidizer will be utilized in the development of a more efficient vol-oxidizer with higher
Finding the missing plastic -resolving the global mass (im)balance for plastic pollution in the ocean

Science.gov (United States)

Wilcox, C.; van Sebille, E.

2016-02-01

Several global studies have attempted to estimate the standing stock of plastic debris in the oceans at the global scale. However, recent work estimating the amount lost from land on an annual basis suggests that the standing stock should be several orders of magnitude larger than the global estimates. We investigate the role of coastal deposition within the first few weeks after plastic enters the ocean and very near its sources, one of the hypothesized sinks for the missing plastic in this mass balance. We utilize a continental scale dataset of plastics collected along Australia's coast and in the offshore regions together with models of plastic release and transport based on Lagrangian tracking to investigate the role of local deposition in the coastal environment. Our models predict that the vast majority of positively buoyant plastic is deposited within a very short distance from its release point, with only a small fraction escaping into the open ocean. These predictions match our coastal and offshore observations, providing clear evidence that this mechanism of immediate coastal deposition is, at least in part, driving the apparent mismatch between coastal emissions and the standing stock in the ocean.
Long-term sorption of metals is similar among plastic types: implications for plastic debris in aquatic environments.

Directory of Open Access Journals (Sweden)

Chelsea M Rochman

Full Text Available Concerns regarding plastic debris and its ability to accumulate large concentrations of priority pollutants in the aquatic environment led us to quantify relationships between different types of mass-produced plastic and metals in seawater. At three locations in San Diego Bay, we measured the accumulation of nine targeted metals (aluminum, chromium, manganese, iron, cobalt, nickel, zinc, cadmium and lead sampling at 1, 3, 6, 9 and 12 months, to five plastic types: polyethylene terephthalate (PET, high-density polyethylene (HDPE, polyvinyl chloride (PVC, low-density polyethylene (LDPE, and polypropylene (PP. Accumulation patterns were not consistent over space and time, and in general all types of plastic tended to accumulate similar concentrations of metals. When we did observe significant differences among concentrations of metals at a single sampling period or location in San Diego Bay, we found that HDPE typically accumulated lesser concentrations of metals than the other four polymers. Furthermore, over the 12-month study period, concentrations of all metals increased over time, and chromium, manganese, cobalt, nickel, zinc and lead did not reach saturation on at least one plastic type during the entire 12-month exposure. This suggests that plastic debris may accumulate greater concentrations of metals the longer it remains at sea. Overall, our work shows that a complex mixture of metals, including those listed as priority pollutants by the US EPA (Cd, Ni, Zn and Pb, can be found on plastic debris composed of various plastic types.
Long-term sorption of metals is similar among plastic types: implications for plastic debris in aquatic environments.

Science.gov (United States)

Rochman, Chelsea M; Hentschel, Brian T; Teh, Swee J

2014-01-01

Concerns regarding plastic debris and its ability to accumulate large concentrations of priority pollutants in the aquatic environment led us to quantify relationships between different types of mass-produced plastic and metals in seawater. At three locations in San Diego Bay, we measured the accumulation of nine targeted metals (aluminum, chromium, manganese, iron, cobalt, nickel, zinc, cadmium and lead) sampling at 1, 3, 6, 9 and 12 months, to five plastic types: polyethylene terephthalate (PET), high-density polyethylene (HDPE), polyvinyl chloride (PVC), low-density polyethylene (LDPE), and polypropylene (PP). Accumulation patterns were not consistent over space and time, and in general all types of plastic tended to accumulate similar concentrations of metals. When we did observe significant differences among concentrations of metals at a single sampling period or location in San Diego Bay, we found that HDPE typically accumulated lesser concentrations of metals than the other four polymers. Furthermore, over the 12-month study period, concentrations of all metals increased over time, and chromium, manganese, cobalt, nickel, zinc and lead did not reach saturation on at least one plastic type during the entire 12-month exposure. This suggests that plastic debris may accumulate greater concentrations of metals the longer it remains at sea. Overall, our work shows that a complex mixture of metals, including those listed as priority pollutants by the US EPA (Cd, Ni, Zn and Pb), can be found on plastic debris composed of various plastic types.
Plastics recycling: challenges and opportunities

OpenAIRE

Hopewell, Jefferson; Dvorak, Robert; Kosior, Edward

2009-01-01

Plastics are inexpensive, lightweight and durable materials, which can readily be moulded into a variety of products that find use in a wide range of applications. As a consequence, the production of plastics has increased markedly over the last 60 years. However, current levels of their usage and disposal generate several environmental problems. Around 4 per cent of world oil and gas production, a non-renewable resource, is used as feedstock for plastics and a further 3–4% is expended to pro...
ARE PLASTIC GROCERY BAGS SACKING THE ENVIRONMENT?

OpenAIRE

Mangal Gogte

2009-01-01

This paper is oriented on analysis impacts of plastic bags on environment. In this paper is analyzed did plastic bags are so harmful, and what are the main ingredients of it. One part of this paper is oriented on effects of plastic bags and management of their usage. There is also made comparative analysis between impacts of plastic and paper bags on environment.
DOE fundamentals handbook: Chemistry

International Nuclear Information System (INIS)

1993-01-01

This handbook was developed to assist nuclear facility operating contractors in providing operators, maintenance personnel, and the technical staff with the necessary fundamentals training to ensure a basic understanding of chemistry. This volume contains the following modules: reactor water chemistry (effects of radiation on water chemistry, chemistry parameters), principles of water treatment (purpose; treatment processes [ion exchange]; dissolved gases, suspended solids, and pH control; water purity), and hazards of chemicals and gases (corrosives [acids, alkalies], toxic compounds, compressed gases, flammable/combustible liquids)
Plastic surgery and global health: how plastic surgery impacts the global burden of surgical disease.

Science.gov (United States)

Semer, Nadine B; Sullivan, Stephen R; Meara, John G

2010-08-01

The global burden of surgical disease is estimated as being 11% of the total global burden of disease. In this article we discuss the portion of this burden which could be ameliorated with plastic surgical expertise. Although not necessarily seen as a major player in issues related to global health, plastic surgeons are uniquely qualified to decrease the burden of surgical disease afflicting people in the developing world. Burns, traumatic injuries, and congenital anomalies are some of the areas where the presence of plastic surgical expertise can make a significant difference in patient outcomes and thereby decrease the years of life lost due to disability due to these highly treatable conditions. In light of the severe shortage of plastic surgeons throughout the developing world, it falls to those concentrated in the developed world to harness their skills and address the vast unmet needs of the developing world so as to enhance global health. Copyright 2009 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.
Translation-rotation plasticity as basic mechanism of plastic deformation in macro-, micro- and nanoindentation processes

International Nuclear Information System (INIS)

Grabco, D; Shikimaka, O; Harea, E

2008-01-01

This paper presents a brief review of multilateral examinations for the purpose of detection of interrelation between processes occuring in solids at different levels of action of exterior loading, namely, at macro-, micro- and nanoindentation. Convincing arguments supporting the rotation deformation mechanism alongside the recognized dislocation one are adduced. It has been shown that the decrease in dislocation mobility leads at all scales to the intensification of rotation plasticity and to the involvement of other plastic deformation mechanisms, such as appearance and interaction of disclinations, twinning, phase transition and compression of material. The conversion from translation plasticity to the rotation-translation one means transition to the higher level of plastic deformation, the mesolevel, when the possibilities of the previous microscopic level are exhausted. It was established that the plastic deformation zone in the vicinity of indentations could be separated into two main specific regions: (i) peripheral region predominantly with the dislocation deformation mechanism; otherwise, translation mechanism: microlevel, and (ii) quasidestructured region mainly with the disclination or the intergranular sliding mechanism: rotation mechanism, mesolevel
Use of recycled plastics in concrete: A critical review.

Science.gov (United States)

Gu, Lei; Ozbakkaloglu, Togay

2016-05-01

Plastics have become an essential part of our modern lifestyle, and the global plastic production has increased immensely during the past 50years. This has contributed greatly to the production of plastic-related waste. Reuse of waste and recycled plastic materials in concrete mix as an environmental friendly construction material has drawn attention of researchers in recent times, and a large number of studies reporting the behavior of concrete containing waste and recycled plastic materials have been published. This paper summarizes the current published literature until 2015, discussing the material properties and recycling methods of plastic and the influence of plastic materials on the properties of concrete. To provide a comprehensive review, a total of 84 studies were considered, and they were classified into sub categories based on whether they dealt with concrete containing plastic aggregates or plastic fibers. Furthermore, the morphology of concrete containing plastic materials is described in this paper to explain the influence of plastic aggregates and plastic fibers on the properties of concrete. The properties of concretes containing virgin plastic materials were also reviewed to establish their similarities and differences with concrete containing recycled plastics. Copyright © 2016 Elsevier Ltd. All rights reserved.
Plasticized chitosan/polyolefin films produced by extrusion.

Science.gov (United States)

Matet, Marie; Heuzey, Marie-Claude; Ajji, Abdellah; Sarazin, Pierre

2015-03-06

Plasticized chitosan and polyethylene blends were produced through a single-pass extrusion process. Using a twin-screw extruder, chitosan plasticization was achieved in the presence of an acetic acid solution and glycerol, and directly mixed with metallocene polyethylene, mPE, to produce a masterbatch. Different dilutions of the masterbatch (2, 5 and 10 wt% of plasticized chitosan), in the presence of ethylene vinyl acetate, EVA, were subsequently achieved in single screw film extrusion. Very small plasticized chitosan domains (number average diameter <5 μm) were visible in the polymeric matrix. The resulting films presented a brown color and increasing haze with chitosan plasticized content. Mechanical properties of the mPE films were affected by the presence of plasticized chitosan, but improvement was observed as a result of some compatibility between mPE and chitosan in the presence of EVA. Finally the incorporation of plasticized chitosan affected mPE water vapor permeability while oxygen permeability remained constant. Copyright © 2014 Elsevier Ltd. All rights reserved.
South African Journal of Higher Education - Vol 19 (2005)

African Journals Online (AJOL)

South African Journal of Higher Education - Vol 19 (2005) ... The 'idea of engagement' and 'the African University in the 21st Century': Some ... The challenges of knowledge production by researchers in Public Administration, a South African ...
Estimating transmitted waves of floating breakwater using support vector regression model

Digital Repository Service at National Institute of Oceanography (India)

Mandal, S.; Hegde, A.V.; Kumar, V.; Patil, S.G.

is first mapped onto an m-dimensional feature space using some fixed (nonlinear) mapping, and then a linear model is constructed in this feature space (Ivanciuc Ovidiu 2007). Using mathematical notation, the linear model in the feature space f(x, w... regressive vector machines, Ocean Engineering Journal, Vol – 36, pp 339 – 347, 2009. 3. Ivanciuc Ovidiu, Applications of support vector machines in chemistry, Review in Computational Chemistry, Eds K. B. Lipkouitz and T. R. Cundari, Vol – 23...
Rigid-Plastic Approximations for Predicting Plastic Deformation of Cylindrical Shells Subject to Dynamic Loading

Directory of Open Access Journals (Sweden)

Michelle S. Hoo Fatt

1996-01-01

Full Text Available A theoretical approach was developed for predicting the plastic deformation of a cylindrical shell subject to asymmetric dynamic loads. The plastic deformation of the leading generator of the shell is found by solving for the transverse deflections of a rigid-plastic beam/string-on-foundation. The axial bending moment and tensile force in the beam/string are equivalent to the longitudinal bending moments and membrane forces of the shell, while the plastic foundation force is equivalent to the shell circumferential bending moment and membrane resistances. Closed-form solutions for the transient and final deformation profile of an impulsive loaded shell when it is in a “string” state were derived using the eigenfunction expansion method. These results were compared to DYNA 3D predictions. The analytical predictions of the transient shell and final centerline deflections were within 25% of the DYNA 3D results.
Application of the principle of supramolecular chemistry in the fields of radiochemistry and radiation chemistry

International Nuclear Information System (INIS)

Shen Xinghai; Chen Qingde; Gao Hongcheng

2008-01-01

Supramolecular chemistry, one of the front fields in chemistry, is defined as 'chemistry beyond the molecule', bearing on the organized entities of higher complexity that result from the association of two or more chemical species held together by intermolecular forces. This article focuses on the application of the principle of supramolecular chemistry in the fields of radiochemistry and radiation chemistry. The following aspects are concerned: (1) the recent progress of supramolecular chemistry; (2) the application of the principle of supramolecular chemistry and the functions of supramolecular system, i.e., recognition, assembly and translocation, in the extraction of nuclides; (3) the application of microemulsion, ionic imprinted polymers, ionic liquids and cloud point extraction in the enrichment of nuclides; (4) the radiation effect of supramolecular systems. (authors)
Leaching of plastic additives to marine organisms

International Nuclear Information System (INIS)

Koelmans, Albert A.; Besseling, Ellen; Foekema, Edwin M.

2014-01-01

It is often assumed that ingestion of microplastics by aquatic species leads to increased exposure to plastic additives. However, experimental data or model based evidence is lacking. Here we assess the potential of leaching of nonylphenol (NP) and bisphenol A (BPA) in the intestinal tracts of Arenicola marina (lugworm) and Gadus morhua (North Sea cod). We use a biodynamic model that allows calculations of the relative contribution of plastic ingestion to total exposure of aquatic species to chemicals residing in the ingested plastic. Uncertainty in the most crucial parameters is accounted for by probabilistic modeling. Our conservative analysis shows that plastic ingestion by the lugworm yields NP and BPA concentrations that stay below the lower ends of global NP and BPA concentration ranges, and therefore are not likely to constitute a relevant exposure pathway. For cod, plastic ingestion appears to be a negligible pathway for exposure to NP and BPA. - Highlights: • Uptake of plastic additives after plastic ingestion was modeled for worms and fish. • This was done for bisphenol A and nonylphenol. • Uncertainty was accounted for by Monte Carlo simulations. • It appeared that exposure by plastic ingestion was negligible for fish. • Plastic ingestion may occasionally be relevant for marine worms. - Leaching of nonylphenol and bisphenol A from ingested microplastic may be relevant for the lugworm, but is irrelevant for fish like cod
Henry Taube and Coordination Chemistry

Science.gov (United States)

dropdown arrow Site Map A-Z Index Menu Synopsis Henry Taube and Coordination Chemistry Resources with Professor of Chemistry, Emeritus, at Stanford University, received the 1983 Nobel Prize in Chemistry " there from 1940-41. "I became deeply interested in chemistry soon after I came to Berkeley,"

Plastics and environmental health: the road ahead.

Science.gov (United States)

North, Emily J; Halden, Rolf U

2013-01-01

Plastics continue to benefit society in innumerable ways, even though recent public focus on plastics has centered mostly on human health and environmental concerns, including their endocrine-disrupting properties and the long-term pollution they represent. The benefits of plastics are particularly apparent in medicine and public health. Plastics are versatile, cost-effective, require less energy to produce than alternative materials like metal or glass, and can be manufactured to have many different properties. Due to these characteristics, polymers are used in diverse health applications like disposable syringes and intravenous bags, sterile packaging for medical instruments as well as in joint replacements, tissue engineering, etc. However, not all current uses of plastics are prudent and sustainable, as illustrated by the widespread, unwanted human exposure to endocrine-disrupting bisphenol A (BPA) and di-(2-ethylhexyl)phthalate (DEHP), problems arising from the large quantities of plastic being disposed of, and depletion of non-renewable petroleum resources as a result of the ever-increasing mass production of plastic consumer articles. Using the health-care sector as example, this review concentrates on the benefits and downsides of plastics and identifies opportunities to change the composition and disposal practices of these invaluable polymers for a more sustainable future consumption. It highlights ongoing efforts to phase out DEHP and BPA in the health-care and food industry and discusses biodegradable options for plastic packaging, opportunities for reducing plastic medical waste, and recycling in medical facilities in the quest to reap a maximum of benefits from polymers without compromising human health or the environment in the process.
Plastics and Environmental Health: The Road Ahead

Science.gov (United States)

North, Emily J.; Halden, Rolf U.

2013-01-01

Plastics continue to benefit society in innumerable ways, even though recent public focus on plastics has centered mostly on human health and environmental concerns, including endocrine-disrupting properties and long-term pollution. The benefits of plastics are particularly apparent in medicine and public health. Plastics are versatile, cost-effective, require less energy to produce than alternative materials – such as metal or glass – and can be manufactured to have many different properties. Due to these characteristics, polymers are used in diverse health applications, such as disposable syringes and intravenous bags, sterile packaging for medical instruments as well as in joint replacements, tissue engineering, etc. However, not all current uses of plastics are prudent and sustainable, as illustrated by widespread, unwanted human exposure to endocrine-disrupting bisphenol-A (BPA) and di-(2-ethylhexyl)phthalate (DEHP), problems arising from the large quantities of plastic being disposed of, and depletion of non-renewable petroleum resources as a result of ever increasing mass-production of plastic consumer articles. By example of the healthcare sector, this review concentrates on benefits and downsides of plastics and identities opportunities to change the composition and disposal practices of these invaluable polymers for a more sustainable future consumption. It highlights ongoing efforts to phase out DEHP and BPA in the healthcare and food industry, and discusses biodegradable options for plastic packaging, opportunities for reducing plastic medical waste, and recycling in medical facilities in the quest to reap a maximum of benefits from polymers without compromising human health or the environment in the process. PMID:23337043
ARE PLASTIC GROCERY BAGS SACKING THE ENVIRONMENT?

Directory of Open Access Journals (Sweden)

Mangal Gogte

2009-12-01

Full Text Available This paper is oriented on analysis impacts of plastic bags on environment. In this paper is analyzed did plastic bags are so harmful, and what are the main ingredients of it. One part of this paper is oriented on effects of plastic bags and management of their usage. There is also made comparative analysis between impacts of plastic and paper bags on environment.
Motor cortical plasticity in Parkinson’s disease

Directory of Open Access Journals (Sweden)

Kaviraja eUdupa

2013-09-01

Full Text Available In Parkinson’s disease (PD, there are alterations of the basal ganglia (BG thalamo-cortical networks, primarily due to degeneration of nigrostrial dopaminergic neurons. These changes in subcortical networks lead to plastic changes in primary motor cortex (M1, which mediates cortical motor output and is a potential target for treatment of PD. Studies investigating the motor cortical plasticity using non-invasive transcranial magnetic stimulation (TMS have found altered plasticity in PD, but there are inconsistencies among these studies. This is likely because plasticity depends on many factors such as the extent of dopaminergic loss and disease severity, response to dopaminergic replacement therapies, development of L-dopa-induced dyskinesias (LID, the plasticity protocol used, medication and stimulation status in patients treated with deep brain stimulation (DBS. The influences of LID and DBS on BG and M1 plasticity have been explored in animal models and in PD patients. In addition, many other factors such age, genetic factors (e.g. brain derived neurotropic factor and other neurotransmitters or receptors polymorphism, emotional state, time of the day, physical fitness have been documented to play role in the extent of plasticity induced by TMS in human studies. In this review, we summarize the studies that investigated M1 plasticity in PD and demonstrate how these afore-mentioned factors affect motor cortical plasticity in PD. We conclude that it is important to consider the clinical, demographic and technical factors that influence various plasticity protocols while developing these protocols as diagnostic or prognostic tools in PD. We also discuss how the modulation of cortical excitability and the plasticity with these non-invasive brain stimulation techniques facilitate the understanding of the pathophysiology of PD and help design potential therapeutic possibilities in this disorder.
Mizan Law Review - Vol 5, No 2 (2011)

African Journals Online (AJOL)

Mizan Law Review - Vol 5, No 2 (2011) ... Ethiopian Law of International Carriage by Air: An Overview · EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT ... Comment: Overview of the Core Changes in the New Ethiopian Urban Land Leasehold Proclamation · EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT
AECL research programs in chemistry

International Nuclear Information System (INIS)

Crocker, I.H.; Eastwood, T.A.; Smith, D.R.; Stewart, R.B.; Tomlinson, M.; Torgerson, D.F.

1980-09-01

Fundamental or underlying research in chemistry is being done in AECL laboratories to further the understanding of processes involved in current nuclear energy systems and maintain an awareness of progress at the frontiers of chemical research so that new advances can be turned to advantage in future AECL endeavours. The report introduces the current research topics and describes them briefly under the following headings: radiation chemistry, isotope separation, high temperature solution chemistry, fuel reprocessing chemistry, and analytical chemistry. (auth)
(JASR) Vol. 12, No. 2, 2012 DEPLETING FOREST RESOURCES

African Journals Online (AJOL)

HP

deteriorating forest resources of Nigeria and its impact on climate change. Key words: Forest Resources, ... Mangrove Forest. Sub Total. 905,930 .... South America” Global Biogeographical Cycle vol 9, pp 329-350. Miller, K. R., Reid, W. V., ...
Pan African Medical Journal - Vol 16, No 1 (2014)

African Journals Online (AJOL)

Pan African Medical Journal - Vol 16, No 1 (2014) .... Cancer incidence in Morocco: report from Casablanca registry 2005-2007 · EMAIL FREE FULL .... Maladie de Leo-Buerger faisant suite à une intoxication au cannabis · EMAIL FREE FULL ...
African Heath Sciences Vol 8 No 1.p65

African Journals Online (AJOL)

Harriet

African Health Sciences Vol 8 No 1 March 2008. 36 ... Objective:To highlight difficulties in the diagnosis and management of non-traumatic perforation of small bowel. Material and ..... of three operations for typhoid perforation. Br J Surg. 1997;.
Managing plastic waste in East Africa: Niche innovations in plastic production and solid waste

NARCIS (Netherlands)

Ombis, L.O.; Vliet, van B.J.M.; Mol, A.P.J.

2015-01-01

This paper assesses the uptake of environmental innovation practices to cope with plastic waste in Kenyan urban centres at the interface of solid waste management and plastic production systems. The Multi Level Perspective on Technological Transitions is used to evaluate 7 innovation pathways of
Analysis of Students’ Missed Organic Chemistry Quiz Questions that Stress the Importance of Prior General Chemistry Knowledge

OpenAIRE

Julie Ealy

2018-01-01

A concern about students’ conceptual difficulties in organic chemistry prompted this study. It was found that prior knowledge from general chemistry was critical in organic chemistry, but what were some of the concepts that comprised that prior knowledge? Therefore an analysis of four years of organic chemistry quiz data was undertaken. Multiple general chemistry concepts were revealed that are essential prior knowledge in organic chemistry. The general chemistry concepts that were foun...
Catherine Malabou’s Hegel: One or several plasticities?

Directory of Open Access Journals (Sweden)

Moder Gregor

2015-01-01

Full Text Available Through an original and extraordinarily fruitful reading of the Hegelian conception of negativity, Catherine Malabou developed the concept of plasticity which she keeps working on as one of her cardinal concepts even to this day. Engaging in the problematic of unity in Hegel, the paper takes on the task of trying to answer the question whether plasticity is one or are there several plasticities. The author argues that one must be careful not to reduce the inherent multiple of plasticity to a single plasticity which becomes plasticity par excellence: the plasticity of plastic explosion, of an abrupt and absolute break, to be distinguished from a creative or productive plasticity of habit. Malabou claimed that Hegel was - contrary to what Deleuz read in him - a philosopher of conceptual multitude as a multitude which cannot be reduced to only one image, the image of unity. If this is true, then the concept of plasticity itself with which she grasped the essence of Hegel’s dialectics, should be understood at least as a “unity in conflict”, if not as an inorganic, inhomogeneous, composed unity - and perhaps even as a unity of the pack.
Degradation of plastic carrier bags in the marine environment

International Nuclear Information System (INIS)

O'Brine, Tim; Thompson, Richard C.

2010-01-01

Research highlights: → There is considerable concern about the hazards that plastic debris presents to wildlife. → Here we investigate breakdown of oxodegradable, compostable and conventional plastic bags. → Compostable plastic disappeared from our test rig between 16 and 24 weeks. → Approximately 98% of the other plastics remained after 40 weeks. → Fouling by marine organisms substantially reduced the amount of UV-light reaching the plastic. - Abstract: There is considerable concern about the hazards that plastic debris presents to wildlife. Use of polymers that degrade more quickly than conventional plastics presents a possible solution to this problem. Here we investigate breakdown of two oxo-biodegradable plastics, compostable plastic and standard polyethylene in the marine environment. Tensile strength of all materials decreased during exposure, but at different rates. Compostable plastic disappeared from our test rig between 16 and 24 weeks whereas approximately 98% of the other plastics remained after 40 weeks. Some plastics require UV light to degrade. Transmittance of UV through oxo-biodegradable and standard polyethylene decreased as a consequence of fouling such that these materials received ∼90% less UV light after 40 weeks. Our data indicate that compostable plastics may degrade relatively quickly compared to oxo-biodegradable and conventional plastics. While degradable polymers offer waste management solutions, there are limitations to their effectiveness in reducing hazards associated with plastic debris.
Electrostatics in Chemistry

Indian Academy of Sciences (India)

fundamental concepts of electrostatics as applied to atoms and molecules. The electric ... chemistry, the chemistry of the covalent bond, deals with the structures ..... the position of an asteroid named Ceres ... World Scientific. Singapore, 1992.
Dictionary of plastics. 7. rev. ed. Kunststoff-Lexikon

Energy Technology Data Exchange (ETDEWEB)

Stoeckhert, K [ed.

1981-01-01

The book starts with a list of about 400 acronyms for plastic materials and additives, caoutchouc types, and synthetic fibers. This is followed by a 500-page glossary of plastics and a 200-page appendix listing producers of plastic feedstocks, chemical substances and additives, recoverable materials, processing systems, semi-finished plastic products and end products, machinery, tools and further aids for plastics processing. (HK).
Relational Analysis of College Chemistry-Major Students' Conceptions of and Approaches to Learning Chemistry

Science.gov (United States)

Li, Wei-Ting; Liang, Jyh-Chong; Tsai, Chin-Chung

2013-01-01

The purpose of this research was to examine the relationships between conceptions of learning and approaches to learning in chemistry. Two questionnaires, conceptions of learning chemistry (COLC) and approaches to learning chemistry (ALC), were developed to identify 369 college chemistry-major students' (220 males and 149 females) conceptions of…
Schostakowitsch. Orchesterlieder (Vol. 2), Neeme Järvi / Werner Pfister

Index Scriptorium Estoniae

Pfister, Werner

1996-01-01

Uuest heliplaadist "Schostakowitsch. Orchesterlieder (Vol. 2): Sechs Romanzen op. 21, Sechs Gedichte op. 143a, Suite auf Verse von Michelangelo Buonarroti op. 145a. Göteborger Sinfoniker, Neeme Järvi". DG CD 447 085-2 (WD: 71'06") DDD
Neurogenomic mechanisms of social plasticity.

Science.gov (United States)

Cardoso, Sara D; Teles, Magda C; Oliveira, Rui F

2015-01-01

Group-living animals must adjust the expression of their social behaviour to changes in their social environment and to transitions between life-history stages, and this social plasticity can be seen as an adaptive trait that can be under positive selection when changes in the environment outpace the rate of genetic evolutionary change. Here, we propose a conceptual framework for understanding the neuromolecular mechanisms of social plasticity. According to this framework, social plasticity is achieved by rewiring or by biochemically switching nodes of a neural network underlying social behaviour in response to perceived social information. Therefore, at the molecular level, it depends on the social regulation of gene expression, so that different genomic and epigenetic states of this brain network correspond to different behavioural states, and the switches between states are orchestrated by signalling pathways that interface the social environment and the genotype. Different types of social plasticity can be recognized based on the observed patterns of inter- versus intra-individual occurrence, time scale and reversibility. It is proposed that these different types of social plasticity rely on different proximate mechanisms at the physiological, neural and genomic level. © 2015. Published by The Company of Biologists Ltd.
Advances in quantum chemistry

CERN Document Server

Sabin, John R

2013-01-01

Advances in Quantum Chemistry presents surveys of current topics in this rapidly developing field that has emerged at the cross section of the historically established areas of mathematics, physics, chemistry, and biology. It features detailed reviews written by leading international researchers. This volume focuses on the theory of heavy ion physics in medicine.Advances in Quantum Chemistry presents surveys of current topics in this rapidly developing field that has emerged at the cross section of the historically established areas of mathematics, physics, chemistry, and biology. It features
Radiochemistry in chemistry and chemistry related undergraduate programmes in Argentina

International Nuclear Information System (INIS)

Fornaciari Iljadica, M.C.; Furnari, J.C.; Cohen, I.M.

2006-01-01

The evolution of education in Argentina at the university level is described. The detailed search of the educational offer shows that less than half of the universities (35 out of 92) include chemistry and chemistry related undergraduate programmes in their curriculum. The revision of the position of radiochemistry in these programmes reveals that only seven courses on radiochemistry are currently offered. Radiochemistry is included only in few programmes in chemistry and biochemistry. With respect to the programmes in chemical engineering the situation is worse. This offer is strongly concentrated in Buenos Aires and its surroundings. (author)

USSR Report, Chemistry

Science.gov (United States)

1987-02-10

acid anhydride with esters of phosphorous acid , which demonstrated that, in reactions of dialkyl phosphites with the anhydride, the... PHOSPHOROUS ACID ESTERS WITH HEPTAFLUOROBUTYRIC ACID ANHYDRIDE. PART 3. DONOR-ACCEPTOR INTERACTIONS Leningrad: ZHURNAL OBSHCHEY KHIMII in Russian Vol 56, No...Reaction of Thioesters and Amidothioesters of Phosphorous Acid With Poly Halogenated Methane Derivatives and Alkyl Halides (0. G. Sinyashin, Sh.
Charge carrier dynamics in PMMA-LiClO4 based polymer electrolytes plasticized with different plasticizers

Science.gov (United States)

Pal, P.; Ghosh, A.

2017-07-01

We have studied the charge carrier dynamics in poly(methylmethacrylate)-LiClO4 polymer electrolytes plasticized with different plasticizers such as ethylene carbonate (EC), propylene carbonate (PC), polyethylene glycol (PEG), and dimethyl carbonate (DMC). We have measured the broadband complex conductivity spectra of these electrolytes in the frequency range of 0.01 Hz-3 GHz and in the temperature range of 203 K-363 K and analyzed the conductivity spectra in the framework of the random barrier model by taking into account the contribution of the electrode polarization observed at low frequencies and/or at high temperatures. It is observed that the temperature dependences of the ionic conductivity and relaxation time follow the Vogel-Tammann-Fulcher relation for all plasticized electrolytes. We have also performed the scaling of the conductivity spectra, which indicates that the charge carrier dynamics is almost independent of temperature and plasticizers in a limited frequency range. The existence of nearly constant loss in these electrolytes has been observed at low temperatures and/or high frequencies. We have studied the dielectric relaxation in these electrolytes using electric modulus formalism and obtained the stretched exponent and the decay function. We have observed less cooperative ion dynamics in electrolytes plasticized with DMC compared to electrolytes plasticized with EC, PC, and PEG.
African Journal of Biotechnology - Vol 12, No 21 (2013)

African Journals Online (AJOL)

African Journal of Biotechnology - Vol 12, No 21 (2013) ... Studies of the genetics of inheritance of stem rust resistance in bread wheat · EMAIL FREE .... Evaluation of the effect of ginger modified cassava starch as thickener in the formulation of ...
UTILIZATION OF WASTE PLASTIC BOTTLES IN ASPHALT MIXTURE

Directory of Open Access Journals (Sweden)

TAHER BAGHAEE MOGHADDAM

2013-06-01

Full Text Available Nowadays, large amounts of waste materials are being produced in the world. One of the waste materials is plastic bottle. Generating disposable plastic bottles is becoming a major problem in many countries. Using waste plastic as a secondary material in construction projects would be a solution to overcome the crisis of producing large amount of waste plastics in one hand and improving the structure’s characteristics such as resistance against cracking on the other hand. This study aimed to investigate the effects of adding plastic bottles in road pavement. Marshall properties as well as specific gravity of asphalt mixture containing different percentages of plastic bottles were evaluated. Besides, Optimum Asphalt Content (OAC was calculated for each percentages of plastic bottles used in the mix. The stiffness and fatigue characteristics of mixture were assessed at OAC value. Results showed that the stability and flow values of asphalt mixture increased by adding waste crushed plastic bottle into the asphalt mixture. Further, it was shown that the bulk specific gravity and stiffness of mixtures increased by adding lower amount of plastic bottles; however, adding higher amounts of plastic resulted in lower specific gravity and mix stiffness. In addition, it was concluded that the mixtures containing waste plastic bottles have lower OAC values compared to the conventional mixture, and this may reduce the amount of asphalt binder can be used in road construction projects. Besides, the mixtures containing waste plastic showed significantly greater fatigue resistance than the conventional mixture.
Cross sections for atomic processes, vol. 2

International Nuclear Information System (INIS)

Takayanagi, Kazuo; Suzuki, Hiroshi; Otani, Shunsuke

1977-09-01

This data collection book contains the data on all processes involving hydrogen and helium isotopes, their ions, electrons and photons, collected systematically and comprehensively, and is compiled subsequently to Vol. 1 as one of the works of the data collection study group in the Institute of Plasma Physics, Nagoya University, Japan. The items of the contents will include energy level, multiplicately excited state, radiation process, electron collision, ionic collision, recombination, collision of neutral atoms, colliding process involving molecules, and other processes. However, the first edition this time contains energy level, radiation process, electron collision and ionic collision, and the data on remaining items are now under collection. Though some criticisms have been heard about Vol. 1, the authors consider that such comprehensive collection based on systematic classification is the foundation of making a generalized data bank expected to become necessary in future. Thus the data collection book includes all relevant processes, and records the experimental data and theoretically calculated results in principle without modification by selecting them systematically. This year, investigation on data evaluation is taken up also as one of the tasks of the study group. (Wakatsuki, Y.)
Chemistry in water reactors

International Nuclear Information System (INIS)

Hermansson, H.P.; Norring, K.

1994-01-01

The international conference Chemistry in Water Reactors was arranged in Nice 24-27/04/1994 by the French Nuclear Energy Society. Examples of technical program areas were primary chemistry, operational experience, fundamental studies and new technology. Furthermore there were sessions about radiation field build-up, hydrogen chemistry, electro-chemistry, condensate polishing, decontamination and chemical cleaning. The conference gave the impression that there are some areas that are going to be more important than others during the next few years to come. Cladding integrity: Professor Ishigure from Japan emphasized that cladding integrity is a subject of great concern, especially with respect to waterside corrosion, deposition and release of crud. Chemistry control: The control of the iron/nickel concentration quotient seems to be not as important as previously considered. The future operation of a nuclear power plant is going to require a better control of the water chemistry than achievable today. One example of this is solubility control via regulation in BWR. Trends in USA: means an increasing use of hydrogen, minimization of SCC/IASCC, minimization of radiation fields by thorough chemistry control, guarding fuel integrity by minimization of cladding corrosion and minimization of flow assisted corrosion. Stellite replacement: The search for replacement materials will continue. Secondary side crevice chemistry: Modeling and practical studies are required to increase knowledge about the crevice chemistry and how it develops under plant operation conditions. Inhibitors: Inhibitors for IGSCC and IGA as well for the primary- (zinc) as for the secondary side (Ti) should be studied. The effects and mode of operation of the inhibitors should be documented. Chemical cleaning: of heat transfer surfaces will be an important subject. Prophylactic cleaning at regular intervals could be one mode of operation
Extruded plastic scintillator for MINERvA

International Nuclear Information System (INIS)

Pla-Dalmau, Anna; Bross, Alan D.; FermilabRykalin, Victor V.; Wood, Brian M.; NICADD, DeKalb

2005-01-01

An extrusion line has recently been installed at Fermilab in collaboration with NICADD (Northern Illinois Center for Accelerator and Detector Development). This new facility will serve to further develop and improve extruded plastic scintillator. Since polystyrene is widely used in the consumer industry, the logical path was to investigate the extrusion of commercial-grade polystyrene pellets with dopants to yield high quality plastic scintillator. The D0 and MINOS experiments are already using extruded scintillator strips in their detectors. A new experiment at Fermilab is pursuing the use of extruded plastic scintillator. A new plastic scintillator strip is being tested and its properties characterized. The initial results are presented here
Spotlight on medicinal chemistry education.

Science.gov (United States)

Pitman, Simone; Xu, Yao-Zhong; Taylor, Peter; Turner, Nicholas; Coaker, Hannah; Crews, Kasumi

2014-05-01

The field of medicinal chemistry is constantly evolving and it is important for medicinal chemists to develop the skills and knowledge required to succeed and contribute to the advancement of the field. Future Medicinal Chemistry spoke with Simone Pitman (SP), Yao-Zhong Xu (YX), Peter Taylor (PT) and Nick Turner (NT) from The Open University (OU), which offers an MSc in Medicinal Chemistry. In the interview, they discuss the MSc course content, online teaching, the future of medicinal chemistry education and The OU's work towards promoting widening participation. SP is a Qualifications Manager in the Science Faculty at The OU. She joined The OU in 1993 and since 1998 has been involved in the Postgraduate Medicinal Chemistry provision at The OU. YX is a Senior Lecturer in Bioorganic Chemistry at The OU. He has been with The OU from 2001, teaching undergraduate courses of all years and chairing the master's course on medicinal chemistry. PT is a Professor of Organic Chemistry at The OU and has been involved with the production and presentation of The OU courses in Science and across the university for over 30 years, including medicinal chemistry modules at postgraduate level. NT is a Lecturer in Analytical Science at The OU since 2009 and has been involved in the production of analytical sciences courses, as well as contributing to the presentation of a number of science courses including medicinal chemistry.
Behavioral Response to Plastic Bag Legislation in Botswana

OpenAIRE

Dikgang, Johane; Visser, Martine

2010-01-01

This paper investigates the use of charges and standards in dealing with a common externality, plastic litter from shopping bags in Botswana. The country passed a plastic bag tax (effective 2007) to curb the plastic bag demand. Interestingly, the legislation did not force retailers to charge for plastic bags, which they did voluntarily at different prices. We assessed the environmental effectiveness and efficiency of the plastic bag legislation by analyzing consumers’ sensitivity to the impro...
PENGARUH PLASTICIZER PADA KARAKTERISTIK EDIBLE FILM DARI PEKTIN

Directory of Open Access Journals (Sweden)

Sang Kompiang Wirawan

2012-05-01

Full Text Available EFFECT OF PLASTICIzER ON THE PECTINIC EDIBLE FILM CHARACTERISTICS. The peel of Balinese Citrus contains high concentration of pectin which can be further processed to be edible films. The edible films can be utilized as a food coating which protects the food from any external mass transports such as humid, oxygen, and soluble material and can be served as a carrier to improve the mechanical-handing properties of the food. Edible films made of organic polymers tend to be brittle and thus addition of a plasticizer is required during the process. The work studies the effect of the type and the concentration of plasticizers on the tensile strength, the elongation of break, and the water vapor permeabilty of the edible film. Sorbitol and glycerol were used as plasticizers. Albedo from the citrus was hydrolized with hydrochloride acid 0.1 N to get pectinate substance. Pectin was then dissolved in water dan mixed with the plasticizers and CaCl2.2H2O solution. The concentrations of the plasticizers were 0, 0.03, 0.05, 0.1, and 0.15 mL/mL of solution. The results showed that increasing the concentration of plasticizers will decrease the tensile strength, but increase the elongation and film permeability. Sorbitol-plasticized films are more brittle, however exhibited higher tensile strength and water vapor permeability than of glycerol-plasticized film. The results suggested that glycerol is better plasticizer than sorbitol. Kulit jeruk bali banyak mengandung pektin yang dapat dimanfaatkan sebagai bahan baku edible film. Edible film bisa digunakan untuk melapisi bahan makanan, melindungi makanan dari transfer massa eksternal seperti kelembaban, oksigen, dan zat terlarut, serta dapat digunakan sebagai carrier untuk meningkatkan penanganan mekanik produk makanan. Film yang terbuat dari bahan polimer organik ini cenderung rapuh sehingga diperlukan penambahan plasticizer. Tujuan dari penelitian ini adalah untuk mengetahui pengaruh kadar dan jenis
High temperature water chemistry monitoring

International Nuclear Information System (INIS)

Aaltonen, P.

1992-01-01

Almost all corrosion phenomena in nuclear power plants can be prevented or at least damped by water chemistry control or by the change of water chemistry control or by the change of water chemistry. Successful water chemistry control needs regular and continuous monitoring of such water chemistry parameters like dissolved oxygen content, pH, conductivity and impurity contents. Conventionally the monitoring is carried out at low pressures and temperatures, which method, however, has some shortcomings. Recently electrodes have been developed which enables the direct monitoring at operating pressures and temperatures. (author). 2 refs, 5 figs
Plastic waste associated with disease on coral reefs.

Science.gov (United States)

Lamb, Joleah B; Willis, Bette L; Fiorenza, Evan A; Couch, Courtney S; Howard, Robert; Rader, Douglas N; True, James D; Kelly, Lisa A; Ahmad, Awaludinnoer; Jompa, Jamaluddin; Harvell, C Drew

2018-01-26

Plastic waste can promote microbial colonization by pathogens implicated in outbreaks of disease in the ocean. We assessed the influence of plastic waste on disease risk in 124,000 reef-building corals from 159 reefs in the Asia-Pacific region. The likelihood of disease increases from 4% to 89% when corals are in contact with plastic. Structurally complex corals are eight times more likely to be affected by plastic, suggesting that microhabitats for reef-associated organisms and valuable fisheries will be disproportionately affected. Plastic levels on coral reefs correspond to estimates of terrestrial mismanaged plastic waste entering the ocean. We estimate that 11.1 billion plastic items are entangled on coral reefs across the Asia-Pacific and project this number to increase 40% by 2025. Plastic waste management is critical for reducing diseases that threaten ecosystem health and human livelihoods. Copyright © 2018, The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.
Can plastic mulching replace irrigation in dryland agriculture?

Science.gov (United States)

Wang, L.; Daryanto, S.; Jacinthe, P. A.

2017-12-01

Increasing water use efficiency (WUE) is a key strategy to maintaining crops yield without over-exploiting the scarce water resource. Plastic mulching technology for wheat and maize has been commonly used in China, but their effect on yield, soil moisture, evapotranspiration (ET), and WUE has not been compared with traditional irrigation method. Using a meta-analysis approach, we quantitatively examined the efficacy of plastic mulching in comparison with traditional irrigation in dryland agriculture. Our results showed that plastic mulching technique resulted in yield increase comparable to irrigated crops but used 24% less water. By covering the ridges with plastic and channeling rainwater into a very narrow planting zone (furrow), plastic mulching increased WUE and available soil moisture. Higher WUE in plastic-mulched croplands was likely a result of greater proportion of available water being used for transpiration than evaporation. If problems related to production costs and residual plastic pollution could be managed, plastic mulching technology would become a promising strategy for dryland farming in other regions.
Seabirds, gyres and global trends in plastic pollution.

Science.gov (United States)

van Franeker, Jan A; Law, Kara Lavender

2015-08-01

Fulmars are effective biological indicators of the abundance of floating plastic marine debris. Long-term data reveal high plastic abundance in the southern North Sea, gradually decreasing to the north at increasing distance from population centres, with lowest levels in high-arctic waters. Since the 1980s, pre-production plastic pellets in North Sea fulmars have decreased by ∼75%, while user plastics varied without a strong overall change. Similar trends were found in net-collected floating plastic debris in the North Atlantic subtropical gyre, with a ∼75% decrease in plastic pellets and no obvious trend in user plastic. The decreases in pellets suggest that changes in litter input are rapidly visible in the environment not only close to presumed sources, but also far from land. Floating plastic debris is rapidly "lost" from the ocean surface to other as-yet undetermined sinks in the marine environment. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.
Linking plastic ingestion research with marine wildlife conservation.

Science.gov (United States)

Avery-Gomm, Stephanie; Borrelle, Stephanie B; Provencher, Jennifer F

2018-05-16

Plastic is an increasingly pervasive marine pollutant. Concomitantly, the number of studies documenting plastic ingestion in wildlife is accelerating. Many of these studies aim to provide a baseline against which future levels of plastic ingestion can be compared, and are motivated by an underlying interest in the conservation of their study species and ecosystems. Although this research has helped to raise the profile of plastic as a pollutant of emerging concern, there is a disconnect between research examining plastic pollution and wildlife conservation. We present ideas to further discussion about how plastic ingestion research could benefit wildlife conservation by prioritising studies that elucidates the significance of plastic pollution as a population-level threat, identifies vulnerable populations, and evaluates strategies for mitigating impacts. The benefit of plastic ingestion research to marine wildlife can be improved by establishing a clearer understanding of how discoveries will be integrated into conservation and policy actions. Copyright © 2018. Published by Elsevier B.V.
Studies of elastic-plastic instabilities

DEFF Research Database (Denmark)

Tvergaard, Viggo

1999-01-01

Analyses of plastic instabilities are reviewed, with focus on results in structural mechanics as well as continuum mechanics. First the basic theories for bifurcation and post-bifurcation behavior are briefly presented. Then, localization of plastic flow is discussed, including shear band formati...
Theoretical chemistry in Belgium a topical collection from theoretical chemistry accounts

CERN Document Server

Champagne, Benoît; De Proft, Frank; Leyssens, Tom

2014-01-01

Readers of this volume can take a tour around the research locations in Belgium which are active in theoretical and computational chemistry. Selected researchers from Belgium present research highlights of their work. Originally published in the journal Theoretical Chemistry Accounts, these outstanding contributions are now available in a hardcover print format. This volume will be of benefit in particular to those research groups and libraries that have chosen to have only electronic access to the journal. It also provides valuable content for all researchers in theoretical chemistry.
Neuromodulation, development and synaptic plasticity.

Science.gov (United States)

Foehring, R C; Lorenzon, N M

1999-03-01

We discuss parallels in the mechanisms underlying use-dependent synaptic plasticity during development and long-term potentiation (LTP) and long-term depression (LTD) in neocortical synapses. Neuromodulators, such as norepinephrine, serotonin, and acetylcholine have also been implicated in regulating both developmental plasticity and LTP/LTD. There are many potential levels of interaction between neuromodulators and plasticity. Ion channels are substrates for modulation in many cell types. We discuss examples of modulation of voltage-gated Ca2+ channels and Ca(2+)-dependent K+ channels and the consequences for neocortical pyramidal cell firing behaviour. At the time when developmental plasticity is most evident in rat cortex, the substrate for modulation is changing as the densities and relative proportions of various ion channels types are altered during ontogeny. We discuss examples of changes in K+ and Ca2+ channels and the consequence for modulation of neuronal activity.
Aktau Plastics Plant Explosives Material Report

Energy Technology Data Exchange (ETDEWEB)

CASE JR.,ROGER S.

1999-12-01

The U.S. Department of Energy (DOE) has been cooperating with the Republic of Kazakhstanin Combined Threat Reduction (CTR) activities at the BN350 reactor located at the Mangyshlak Atomic Energy Complex (MAEC) in the city of Aktau, Kazakhstan since 1994. DOE contract personnel have been stationed at this facility for the last two years and DOE representatives regularly visit this location to oversee the continuing cooperative activities. Continued future cooperation is planned. A Russian news report in September 1999 indicated that 75 metric tons of organic peroxides stored at the Plastics Plant near Aktau were in danger of exploding and killing or injuring nearby residents. To ensure the health and safety of the personnel at the BN350 site, the DOE conducted a study to investigate the potential danger to the BN350 site posed by these materials at the Plastics Plant. The study conclusion was that while the organic peroxides do have hazards associated with them, the BN350 site is a safe distance from the Plastics Plant. Further, because the Plastics Plant and MAEC have cooperative fire-fighting agreements,and the Plastics Plant had exhausted its reserve of fire-fighting foam, there was the possibility of the Plastics Plant depleting the store of fire-fighting foam at the BN350 site. Subsequently, the DOE decided to purchase fire-fighting foam for the Plastics Plant to ensure the availability of free-fighting foam at the BN350 site.
Microbial Enzymatic Degradation of Biodegradable Plastics.

Science.gov (United States)

Roohi; Bano, Kulsoom; Kuddus, Mohammed; Zaheer, Mohammed R; Zia, Qamar; Khan, Mohammed F; Ashraf, Ghulam Md; Gupta, Anamika; Aliev, Gjumrakch

2017-01-01

The renewable feedstock derived biodegradable plastics are important in various industries such as packaging, agricultural, paper coating, garbage bags and biomedical implants. The increasing water and waste pollution due to the available decomposition methods of plastic degradation have led to the emergence of biodegradable plastics and biological degradation with microbial (bacteria and fungi) extracellular enzymes. The microbes utilize biodegradable polymers as the substrate under starvation and in unavailability of microbial nutrients. Microbial enzymatic degradation is suitable from bioremediation point of view as no waste accumulation occurs. It is important to understand the microbial interaction and mechanism involved in the enzymatic degradation of biodegradable plastics under the influence of several environmental factors such as applied pH, thermo-stability, substrate molecular weight and/or complexity. To study the surface erosion of polymer film is another approach for hydrolytic degradation characteristion. The degradation of biopolymer is associated with the production of low molecular weight monomer and generation of carbon dioxide, methane and water molecule. This review reported the degradation study of various existing biodegradable plastics along with the potent degrading microbes (bacteria and fungi). Patents available on plastic biodegradation with biotechnological significance is also summarized in this paper. This paper assesses that new disposal technique should be adopted for the degradation of polymers and further research is required for the economical production of biodegradable plastics along with their enzymatic degradation. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

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