WorldWideScience

Sample records for range 15-16 chemistry

  1. Water chemistry of Rocky Mountain Front Range aquatic ecosystems

    Science.gov (United States)

    Robert C. Musselman; Laura Hudnell; Mark W. Williams; Richard A. Sommerfeld

    1996-01-01

    A study of the water chemistry of Colorado Rocky Mountain Front Range alpine/subalpine lakes and streams in wilderness ecosystems was conducted during the summer of 1995 by the USDA Forest Service Arapaho and Roosevelt National Forests and Rocky Mountain Forest and Range Experiment Station, and the University of Colorado Institute of Alpine and Arctic Research. Data...

  2. 15-16-vuotiaiden lentopalloilijoiden nopeusvoiman kehittyminen sarjakaudella

    OpenAIRE

    Matalamäki, Jenni

    2008-01-01

    Tutkimuksen tarkoituksena oli selvittää lentopalloilijoiden nopeusvoimaa ja sen kehittymistä sarjakaudella. Tutkimukseni kohteena olivat yhden joukkueen kahdeksan 15-16- vuotiasta tyttölentopalloilijaa. Toteutin tutkimukseni sarjakaudella 2007-2008. Tutkimuksen tavoitteena oli tuottaa lisää tietoa nopeusvoimasta ja testata yhden tyttöjoukkueen nopeusvoimaa, jota tarvitaan lentopallossa. Tutkimukseeni keräsin teoriatietoa tukemaan tutkimustani. Keskeisimpiä aiheita olivat tyttöjen ...

  3. Hematology, serum chemistry, and body mass of free-ranging and captive Canada lynx in Minnesota.

    Science.gov (United States)

    Moen, Ron; Rasmussen, James M; Burdett, Christopher L; Pelican, Katharine M

    2010-01-01

    Baseline blood chemistry data could be particularly valuable if reference values from free-ranging populations of rare or endangered species are not available. The Canada lynx (Lynx canadensis) is listed as threatened under the Endangered Species Act in the conterminous United States, even though the species is managed as a furbearer in Alaska and in most provinces of Canada. Body mass, blood chemistry, and hematologic data for free-ranging lynx were collected from 2003 to 2007 and for captive lynx from 1984 to 2007. Up to 2 yr of age, captive lynx were consistently heavier than free-ranging lynx. Body mass of adult free-ranging lynx was similar to body mass of captive adult lynx. Some differences in blood chemistry between free-ranging and captive lynx were statistically significant, but most measured values were within reference ranges for domestic cats. Free-ranging lynx had higher concentrations of aspartate aminotransferase, alanine aminotransferase, and blood urea nitrogen than did captive lynx, and these were outside the reference value ranges for domestic cats. Alkaline phosphatase and phosphorus were higher in juveniles (lynx maintained body mass between serial captures. Hematologic values, blood chemistry values, and body mass of free-ranging Canada lynx provide support for the hypothesis that Canada lynx in Minnesota, at the southern edge of their range, are in normal physical condition.

  4. Research-Based Development of a Lesson Plan on Shower Gels and Musk Fragrances Following a Socio-Critical and Problem-Oriented Approach to Chemistry Teaching

    Science.gov (United States)

    Marks, Ralf; Eilks, Ingo

    2010-01-01

    A case is described of the development of a lesson plan for 10th grade (age range 15-16) chemistry classes on the chemistry of shower gels. The lesson plan follows a socio-critical and problem-oriented approach to chemistry teaching. This means that, aside from learning about the basic chemistry of the components making up modern shower gels in…

  5. Stream chemistry responses to four range management strategies in eastern Oregon.

    Science.gov (United States)

    A.R. Tiedemann; D.A. Higgins; T.M. Quigley; H.R. Sanderson

    1989-01-01

    Responses of stream chemistry parameters, nitrate-N (NO3-N), phosphate (PO4), calcium (Ca), magnesium (Mg), potassium (K), sodium (Na), and hydrogen ion activity (pH) were measured on 13 wildland watersheds managed at four different grazing strategies. Range management strategies tested were (A) no grazing, (B) grazing without control of livestock distribution (8.2 ha/...

  6. Cytokine profiling using monocytes/macrophages cultured on common biomaterials with a range of surface chemistries.

    Science.gov (United States)

    Schutte, Robert J; Parisi-Amon, Andreina; Reichert, W Monty

    2009-01-01

    Cytokines, chemokines, and growth factors were assayed from the supernatants of monocytes and macrophages cultured on common biomaterials with a range of surface chemistries. TNF-alpha, MCP-1, MIP-1alpha, IL-8, IL-6, IL-1beta, VEGF, IL-1ra, and IL-10 were measured from monocyte/macrophage cultures at different stages of activation and differentiation seeded onto polyethylene, polyurethane, expanded polytetrafluoroethylene, polymethyl methacrylate, and a hydrogel copolymer of 2-hydroxyethyl methacrylate, 1-vinyl-2-pyrrolidinone, and polyethylene glycol acrylate in tissue culture polystyrene (TCPS) plates. Empty TCPS wells and organo-tin polyvinyl chloride served as "blanks" and positive controls, respectively. Results showed an overall increase in cytokine, chemokine, and growth factor production as monocytes are activated or differentiated into macrophages and that proinflammatory and anti-wound healing cytokines and chemokines dominate this profile. However, cytokine production was only modestly affected by the surface chemistry of these four stable and noncytotoxic biomaterials. 2008 Wiley Periodicals, Inc.

  7. Weights, hematology and serum chemistry of seven species of free-ranging tropical pelagic seabirds

    Science.gov (United States)

    Work, Thierry M.

    1996-01-01

    I established reference values for weight, hematology, and serum chemistry for seven species of free-ranging Hawaiian tropical pelagic seabirds comprising three orders (Procellariiformes, Pelecaniformes, Charadriiformes) and six families (Procellariidae, Phaethontidae, Diomedeidae, Sulidae, Fregatidae, and Laridae). Species examined included 84 Hawaiian darkrumped petrels (Pterodoma phaeopygia), 90 wedge-tailed shearwaters (Puffinus pacificus), 151 Laysan albatrosses (Diomedea immutabilis), 69 red-footed boobies (Sula sula), 154 red-tailed tropicbirds (Phaeton rubricauda), 90 great frigatebirds (Fregata minor), and 72 sooty terns (Sterna fuscata). Hematocrit, total plasma solids, total and differential white cell counts, serum glucose, calcium, phosphorus, uric acid, total protein, albumin, globulin, aspartate aminotransferase and creatinine phosphokinase were analyzed. Among and within species, hematology and chemistry values varied with age, sex, season, and island of collection. Despite this variation, order-wide trends were observed.

  8. Comprehensive reference ranges for hematology and clinical chemistry laboratory parameters derived from normal Nigerian adults.

    Science.gov (United States)

    Miri-Dashe, Timzing; Osawe, Sophia; Tokdung, Monday; Daniel, Monday Tokdung Nenbammun; Daniel, Nenbammun; Choji, Rahila Pam; Mamman, Ille; Deme, Kurt; Damulak, Dapus; Abimiku, Alash'le

    2014-01-01

    Interpretation of laboratory test results with appropriate diagnostic accuracy requires reference or cutoff values. This study is a comprehensive determination of reference values for hematology and clinical chemistry in apparently healthy voluntary non-remunerated blood donors and pregnant women. Consented clients were clinically screened and counseled before testing for HIV, Hepatitis B, Hepatitis C and Syphilis. Standard national blood donors' questionnaire was administered to consented blood donors. Blood from qualified volunteers was used for measurement of complete hematology and chemistry parameters. Blood samples were analyzed from a total of 383 participants, 124 (32.4%) males, 125 (32.6%) non-pregnant females and 134 pregnant females (35.2%) with a mean age of 31 years. Our results showed that the red blood cells count (RBC), Hemoglobin (HB) and Hematocrit (HCT) had significant gender difference (p = 0.000) but not for total white blood count (p>0.05) which was only significantly higher in pregnant verses non-pregnant women (p = 0.000). Hemoglobin and Hematocrit values were lower in pregnancy (P = 0.000). Platelets were significantly higher in females than men (p = 0.001) but lower in pregnant women (p =  .001) with marked difference in gestational period. For clinical chemistry parameters, there was no significant difference for sodium, potassium and chloride (p>0.05) but gender difference exists for Bicarbonate (HCO3), Urea nitrogen, Creatinine as well as the lipids (p0.05). Hematological and Clinical Chemistry reference ranges established in this study showed significant gender differences. Pregnant women also differed from non-pregnant females and during pregnancy. This is the first of such comprehensive study to establish reference values among adult Nigerians and difference observed underscore the need to establish reference values for different populations.

  9. Comprehensive reference ranges for hematology and clinical chemistry laboratory parameters derived from normal Nigerian adults.

    Directory of Open Access Journals (Sweden)

    Timzing Miri-Dashe

    Full Text Available BACKGROUND: Interpretation of laboratory test results with appropriate diagnostic accuracy requires reference or cutoff values. This study is a comprehensive determination of reference values for hematology and clinical chemistry in apparently healthy voluntary non-remunerated blood donors and pregnant women. METHODS AND FINDINGS: Consented clients were clinically screened and counseled before testing for HIV, Hepatitis B, Hepatitis C and Syphilis. Standard national blood donors' questionnaire was administered to consented blood donors. Blood from qualified volunteers was used for measurement of complete hematology and chemistry parameters. Blood samples were analyzed from a total of 383 participants, 124 (32.4% males, 125 (32.6% non-pregnant females and 134 pregnant females (35.2% with a mean age of 31 years. Our results showed that the red blood cells count (RBC, Hemoglobin (HB and Hematocrit (HCT had significant gender difference (p = 0.000 but not for total white blood count (p>0.05 which was only significantly higher in pregnant verses non-pregnant women (p = 0.000. Hemoglobin and Hematocrit values were lower in pregnancy (P = 0.000. Platelets were significantly higher in females than men (p = 0.001 but lower in pregnant women (p =  .001 with marked difference in gestational period. For clinical chemistry parameters, there was no significant difference for sodium, potassium and chloride (p>0.05 but gender difference exists for Bicarbonate (HCO3, Urea nitrogen, Creatinine as well as the lipids (p0.05. CONCLUSIONS: Hematological and Clinical Chemistry reference ranges established in this study showed significant gender differences. Pregnant women also differed from non-pregnant females and during pregnancy. This is the first of such comprehensive study to establish reference values among adult Nigerians and difference observed underscore the need to establish reference values for different populations.

  10. Adult Hematology and Clinical Chemistry Laboratory Reference Ranges in a Zimbabwean Population.

    Directory of Open Access Journals (Sweden)

    Wadzanai P Samaneka

    Full Text Available Laboratory reference ranges used for clinical care and clinical trials in various laboratories in Zimbabwe were derived from textbooks and research studies conducted more than ten years ago. Periodic verification of these ranges is essential to track changes over time. The purpose of this study was to establish hematology and chemistry laboratory reference ranges using more rigorous methods.A community-based cross-sectional study was carried out in Harare, Chitungwiza, and Mutoko. A multistage sampling technique was used. Samples were transported from the field for analysis at the ISO15189 certified University of Zimbabwe-University of California San Francisco Central Research Laboratory. Hematology and clinical chemistry reference ranges lower and upper reference limits were estimated at the 2.5th and 97.5th percentiles respectively.A total of 769 adults (54% males aged 18 to 55 years were included in the analysis. Median age was 28 [IQR: 23-35] years. Males had significantly higher red cell counts, hemoglobin, hematocrit, and mean corpuscular hemoglobin compared to females. Females had higher white cell counts, platelets, absolute neutrophil counts, and absolute lymphocyte counts compared to males. There were no gender differences in eosinophils, monocytes, and absolute basophil count. Males had significantly higher levels of urea, sodium, potassium, calcium, creatinine, amylase, total protein, albumin and liver enzymes levels compared to females. Females had higher cholesterol and lipase compared with males. There are notable differences in the white cell counts, neutrophils, cholesterol, and creatinine kinase when compared with the currently used reference ranges.Data from this study provides new country specific reference ranges which should be immediately adopted for routine clinical care and accurate monitoring of adverse events in research studies.

  11. Adult Hematology and Clinical Chemistry Laboratory Reference Ranges in a Zimbabwean Population.

    Science.gov (United States)

    Samaneka, Wadzanai P; Mandozana, Gibson; Tinago, Willard; Nhando, Nehemiah; Mgodi, Nyaradzo M; Bwakura-Dangarembizi, Mutsawashe F; Munjoma, Marshall W; Gomo, Zvenyika A R; Chirenje, Zvavahera M; Hakim, James G

    2016-01-01

    Laboratory reference ranges used for clinical care and clinical trials in various laboratories in Zimbabwe were derived from textbooks and research studies conducted more than ten years ago. Periodic verification of these ranges is essential to track changes over time. The purpose of this study was to establish hematology and chemistry laboratory reference ranges using more rigorous methods. A community-based cross-sectional study was carried out in Harare, Chitungwiza, and Mutoko. A multistage sampling technique was used. Samples were transported from the field for analysis at the ISO15189 certified University of Zimbabwe-University of California San Francisco Central Research Laboratory. Hematology and clinical chemistry reference ranges lower and upper reference limits were estimated at the 2.5th and 97.5th percentiles respectively. A total of 769 adults (54% males) aged 18 to 55 years were included in the analysis. Median age was 28 [IQR: 23-35] years. Males had significantly higher red cell counts, hemoglobin, hematocrit, and mean corpuscular hemoglobin compared to females. Females had higher white cell counts, platelets, absolute neutrophil counts, and absolute lymphocyte counts compared to males. There were no gender differences in eosinophils, monocytes, and absolute basophil count. Males had significantly higher levels of urea, sodium, potassium, calcium, creatinine, amylase, total protein, albumin and liver enzymes levels compared to females. Females had higher cholesterol and lipase compared with males. There are notable differences in the white cell counts, neutrophils, cholesterol, and creatinine kinase when compared with the currently used reference ranges. Data from this study provides new country specific reference ranges which should be immediately adopted for routine clinical care and accurate monitoring of adverse events in research studies.

  12. Verification of chemistry reference ranges using a simple method in sub-Saharan Africa

    Science.gov (United States)

    Taylor, Douglas; Mandala, Justin; Nanda, Kavita; Van Campenhout, Christel; Agingu, Walter; Madurai, Lorna; Barsch, Eva-Maria; Deese, Jennifer; Van Damme, Lut; Crucitti, Tania

    2016-01-01

    Background Chemistry safety assessments are interpreted by using chemistry reference ranges (CRRs). Verification of CRRs is time consuming and often requires a statistical background. Objectives We report on an easy and cost-saving method to verify CRRs. Methods Using a former method introduced by Sigma Diagnostics, three study sites in sub-Saharan Africa, Bondo, Kenya, and Pretoria and Bloemfontein, South Africa, verified the CRRs for hepatic and renal biochemistry assays performed during a clinical trial of HIV antiretroviral pre-exposure prophylaxis. The aspartate aminotransferase/alanine aminotransferase, creatinine and phosphorus results from 10 clinically-healthy participants at the screening visit were used. In the event the CRRs did not pass the verification, new CRRs had to be calculated based on 40 clinically-healthy participants. Results Within a few weeks, the study sites accomplished verification of the CRRs without additional costs. The aspartate aminotransferase reference ranges for the Bondo, Kenya site and the alanine aminotransferase reference ranges for the Pretoria, South Africa site required adjustment. The phosphorus CRR passed verification and the creatinine CRR required adjustment at every site. The newly-established CRR intervals were narrower than the CRRs used previously at these study sites due to decreases in the upper limits of the reference ranges. As a result, more toxicities were detected. Conclusion To ensure the safety of clinical trial participants, verification of CRRs should be standard practice in clinical trials conducted in settings where the CRR has not been validated for the local population. This verification method is simple, inexpensive, and can be performed by any medical laboratory. PMID:28879112

  13. Verification of chemistry reference ranges using a simple method in sub-Saharan Africa

    Directory of Open Access Journals (Sweden)

    Irith De Baetselier

    2016-10-01

    Full Text Available Background: Chemistry safety assessments are interpreted by using chemistry reference ranges (CRRs. Verification of CRRs is time consuming and often requires a statistical background. Objectives: We report on an easy and cost-saving method to verify CRRs. Methods: Using a former method introduced by Sigma Diagnostics, three study sites in sub- Saharan Africa, Bondo, Kenya, and Pretoria and Bloemfontein, South Africa, verified the CRRs for hepatic and renal biochemistry assays performed during a clinical trial of HIV antiretroviral pre-exposure prophylaxis. The aspartate aminotransferase/alanine aminotransferase, creatinine and phosphorus results from 10 clinically-healthy participants at the screening visit were used. In the event the CRRs did not pass the verification, new CRRs had to be calculated based on 40 clinically-healthy participants. Results: Within a few weeks, the study sites accomplished verification of the CRRs without additional costs. The aspartate aminotransferase reference ranges for the Bondo, Kenya site and the alanine aminotransferase reference ranges for the Pretoria, South Africa site required adjustment. The phosphorus CRR passed verification and the creatinine CRR required adjustment at every site. The newly-established CRR intervals were narrower than the CRRs used previously at these study sites due to decreases in the upper limits of the reference ranges. As a result, more toxicities were detected. Conclusion: To ensure the safety of clinical trial participants, verification of CRRs should be standard practice in clinical trials conducted in settings where the CRR has not been validated for the local population. This verification method is simple, inexpensive, and can be performed by any medical laboratory.

  14. Verification of chemistry reference ranges using a simple method in sub-Saharan Africa

    Directory of Open Access Journals (Sweden)

    Irith De Baetselier

    2016-02-01

    Full Text Available Background: Chemistry safety assessments are interpreted by using chemistry reference ranges (CRRs. Verification of CRRs is time consuming and often requires a statistical background.Objectives: We report on an easy and cost-saving method to verify CRRs.Methods: Using a former method introduced by Sigma Diagnostics, three study sites in sub- Saharan Africa, Bondo, Kenya, and Pretoria and Bloemfontein, South Africa, verified the CRRs for hepatic and renal biochemistry assays performed during a clinical trial of HIV antiretroviral pre-exposure prophylaxis. The aspartate aminotransferase/alanine aminotransferase, creatinine and phosphorus results from 10 clinically-healthy participants at the screening visit were used. In the event the CRRs did not pass the verification, new CRRs had to be calculated based on 40 clinically-healthy participants.Results: Within a few weeks, the study sites accomplished verification of the CRRs without additional costs. The aspartate aminotransferase reference ranges for the Bondo, Kenya site and the alanine aminotransferase reference ranges for the Pretoria, South Africa site required adjustment. The phosphorus CRR passed verification and the creatinine CRR required adjustment at every site. The newly-established CRR intervals were narrower than the CRRs used previously at these study sites due to decreases in the upper limits of the reference ranges. As a result, more toxicities were detected.Conclusion: To ensure the safety of clinical trial participants, verification of CRRs should be standard practice in clinical trials conducted in settings where the CRR has not been validated for the local population. This verification method is simple, inexpensive, and can be performed by any medical laboratory.

  15. Verification of chemistry reference ranges using a simple method in sub-Saharan Africa.

    Science.gov (United States)

    De Baetselier, Irith; Taylor, Douglas; Mandala, Justin; Nanda, Kavita; Van Campenhout, Christel; Agingu, Walter; Madurai, Lorna; Barsch, Eva-Maria; Deese, Jennifer; Van Damme, Lut; Crucitti, Tania

    2016-01-01

    Chemistry safety assessments are interpreted by using chemistry reference ranges (CRRs). Verification of CRRs is time consuming and often requires a statistical background. We report on an easy and cost-saving method to verify CRRs. Using a former method introduced by Sigma Diagnostics, three study sites in sub-Saharan Africa, Bondo, Kenya, and Pretoria and Bloemfontein, South Africa, verified the CRRs for hepatic and renal biochemistry assays performed during a clinical trial of HIV antiretroviral pre-exposure prophylaxis. The aspartate aminotransferase/alanine aminotransferase, creatinine and phosphorus results from 10 clinically-healthy participants at the screening visit were used. In the event the CRRs did not pass the verification, new CRRs had to be calculated based on 40 clinically-healthy participants. Within a few weeks, the study sites accomplished verification of the CRRs without additional costs. The aspartate aminotransferase reference ranges for the Bondo, Kenya site and the alanine aminotransferase reference ranges for the Pretoria, South Africa site required adjustment. The phosphorus CRR passed verification and the creatinine CRR required adjustment at every site. The newly-established CRR intervals were narrower than the CRRs used previously at these study sites due to decreases in the upper limits of the reference ranges. As a result, more toxicities were detected. To ensure the safety of clinical trial participants, verification of CRRs should be standard practice in clinical trials conducted in settings where the CRR has not been validated for the local population. This verification method is simple, inexpensive, and can be performed by any medical laboratory.

  16. Modelling atmospheric chemistry and long-range transport of emerging Asian pollutants

    CERN Document Server

    Wang, Kuo-Ying

    2008-01-01

    Modeling is a very important tool for scientific processes, requiring long-term dedication, desire, and continuous reflection. In this work, we discuss several aspects of modeling, and the reasons for doing it. We discuss two major modeling systems that have been built by us over the last 10 years. It is a long and arduous process but the reward of understanding can be enormous, as demonstrated in the examples shown in this work. We found that long-range transport of emerging Asian pollutants can be interpreted using a Lagrangian framework for wind analysis. More detailed processes still need to be modeled but an accurate representation of the wind structure is the most important thing above all others. Our long-term chemistry integrations reveal the capability of the IMS model in simulating tropospheric chemistry on a climate scale. These long-term integrations also show ways for further model development. Modeling is a quantitative process, and the understanding can be sustained only when theories are vigor...

  17. Serum chemistry comparisons between captive and free-ranging giraffes (Giraffa camelopardalis).

    Science.gov (United States)

    Schmidt, Debra A; Barbiers, Robyn B; Ellersieck, Mark R; Ball, Ray L; Koutsos, Elizabeth A; Griffin, Mark E; Grobler, Douw; Citino, Scott B; Bush, Mitchell

    2011-03-01

    Serum chemistry analyses were compared between captive and free-ranging giraffes (Giraffa camelopardalis) in an attempt to better understand some of the medical issues seen with captive giraffes. Illnesses, including peracute mortality, energy malnutrition, pancreatic disease, urolithiasis, hoof disease, and severe intestinal parasitism, may be related to zoo nutrition and management issues. Serum samples were collected from 20 captive giraffes at 10 United States institutions. Thirteen of the captive animal samples were collected from animals trained for blood collection; seven were banked samples obtained from a previous serum collection. These samples were compared with serum samples collected from 24 free-ranging giraffes in South Africa. Differences between captive and free-ranging giraffes, males and females, and adults and subadults were analyzed by using a 2 x 2 x 2 factorial and Fisher's least significant difference for mean separation; when necessary variables were ranked and analyzed via analysis of variance. Potassium and bilirubin concentrations and alanine aminotransferase (ALT) activities were different between captive and free-ranging giraffes, but all fell within normal bovid reference ranges. The average glucose concentration was significantly elevated in free-ranging giraffes (161 mg/dl) compared with captive giraffes (113 mg/dl). All giraffes in this study had glucose concentrations higher than bovine (42-75 mg/ dl) and caprine (48-76 mg/dl) reference ranges. Differences were also seen in lipase, chloride, and magnesium though these findings are likely not clinically significant. There were no differences detected between sexes. Adults had higher concentrations of potassium, total protein, globulins, and chloride and higher gamma glutamyltransferase activities, whereas subadults had higher concentrations of phosphorus. Within the captive group, nonimmobilized animals had higher concentrations of total protein and globulins. Captive giraffe diets

  18. Jeremiah 33:15-16 as a reinterpretation of Jeremiah 23:5-6 ...

    African Journals Online (AJOL)

    There are striking similarities between Jeremiah 23:5-6 and Jeremiah 33:15-16. A comparison, however, also shows interesting differences and 33:14-26, furthermore is lacking in the Septuagint tradition. Jeremiah 33:15-16 seems to be a reinterpretation of 23:5-6. This is done by generalising the content, widening the ...

  19. Chemistry?!

    Indian Academy of Sciences (India)

    Chemistry is the science of matter and of its transformations, and life is its highest expression. It provides structures endowed with properties and develops processes for the synthesis of structures. It plays a primordial role in our understanding of material phe- nomena, in our capability to act upon them, to modify them, to.

  20. A roadmap to defining the clinical reportable ranges of chemistry analytes: Increasing automation efficiency and decreasing manual dilutions.

    Science.gov (United States)

    Lo, Sheng-Ying; Baird, Geoffrey S; Greene, Dina N

    2015-12-07

    Proper utilization of resources is an important operational objective for clinical laboratories. To reduce unnecessary manual interventions on automated instruments, we conducted a workflow analysis that optimized dilution parameters and reporting of abnormally high chemistry results for the Beckman AU series of chemistry analyzers while maintaining clinically acceptable reportable ranges. Workflow analysis for the Beckman AU680/5812 and DxC800 chemistry analyzers was performed using historical data. Clinical reportable ranges for 53 chemistry analytes were evaluated. Optimized dilution parameters and upper limit of reportable ranges for the AU680/5812 instruments were derived and validated to meet these reportable ranges. The number of specimens that required manual dilutions before and after optimization was determined for both the AU680/5812 and DxC800, with the DxC800 serving as the reference instrument. Retrospective data analysis revealed that 7700 specimens required manual dilutions on the DxC over a 2-y period. Using our optimized AU-specific dilution and reporting parameters, the data-driven simulation analysis showed a 61% reduction in manual dilutions. For the specimens that required manual dilutions on the AU680/5812, we developed standardized dilution procedures to further streamline workflow. We provide a data-driven, practical outline for clinical laboratories to efficiently optimize their use of automated chemistry analyzers. The outcomes can be used to assist laboratories wishing to improve their existing procedures or to facilitate transitioning into a new line of instrumentation, regardless of the instrument model or manufacturer. Copyright © 2015 Elsevier B.V. All rights reserved.

  1. Jeremiah 33:15-16 as a reinterpretation of Jeremiah 23:5-6

    Directory of Open Access Journals (Sweden)

    W. J. Wessels

    1991-01-01

    Full Text Available There are striking similarities between Jeremiah 23:5-6 and Jeremiah 33:15-16. A comparison, however, also shows interesting differences and 33:14-26, furthermore is lacking in the Septuagint tradition. Jeremiah 33:15-16 seems to be a reinterpretation of 23:5-6. This is done by generalising the content, widening the perspective and shifting the emphasis, for instance, from the king to the city, and adding a legitimate heir of David and a legitimate priest. As fa r as social context is concerned, Jeremiah 33:15-16 should perhaps be linked to the conflict between the disen franchised Levites and the Zadokites who displaced them. The reinterpretation process is an attempt both to explain the non-fulfilment of 23:5-6 and to resolve the dissonance it creates.

  2. Synthesis of high-specific activity [15,16-{sup 3}H{sub 2}]buprenorphine

    Energy Technology Data Exchange (ETDEWEB)

    Oetvoes, F.; Toth, G. [Hungarian Academy of Sciences, Szeged (Hungary). Isotope Lab.; Hosztafi, S.; Simon, C. [Alkaloida Chemical Factory Ltd., Tiszavasvari (Hungary)

    1995-01-01

    Tritium labelling of buprenorphine, a mixed agonist-antagonist opioid ligand, was performed with a specific activity of 2.35 TBq/mmol (63.6 Ci/mmol) starting with 15,16-didehydrobuprenorphine. Labels at positions 15 and 16 of the morphine skeleton proved to be sufficiently stable under strong acidic or basic conditions. (Author).

  3. A note on the chemistry of seawater in the range 350°-500°C

    Science.gov (United States)

    Bischoff, James L.; Rosenbauer, Robert J.

    1983-01-01

    The chemistry of seawater at conditions of 350° to 500°C, 220 to 1000 bars (22 to 100 MPa) is controlled by reactions involving magnesium hydroxide sulfate (MHSH) and anhydrite. During progressive heating from 350° to 500°C at 1000 bars (100 MPa), MHSH with a  ratio of 1.25 is formed via precipitation from solution and via reaction of solution with pre-existing anhydrite. During adiabatic expansion the MHSH extracts additional SO4 from seawater and converts to a stoichiometry in which . These reactions control and greatly change the concentrations of Ca, Mg, SO4 in solution and produce significant ionizable hydrogen, attaining 11.7 mmoles kg−1 at maximum conditions.

  4. Learning Chemistry and beyond with a Lesson Plan on Potato Crisps, Which Follows a Socio-Critical and Problem-Oriented Approach to Chemistry Lessons--A Case Study

    Science.gov (United States)

    Marks, Ralf; Bertram, Stefanie; Eilks, Ingo

    2008-01-01

    This paper discusses a chemistry lesson plan on potato crisps for 10th grade (age range 15-16) chemistry classes in Germany. The lesson plan focuses on the discussion about low-fat and low-carb diets as they are presented in everyday media such as TV or newspapers in Germany. The discussion follows a socio-critical and problem-oriented approach to…

  5. Total synthesis of (S)-(-)-(E)-15,16-dihydrominquartynoic acid: a highly potent anticancer agent.

    Science.gov (United States)

    Gung, Benjamin W; Kumi, Godwin

    2004-05-14

    The conjugated entriyne natural product, (S)-(E)-15,16-dihydrominquartynoic acid (1), is synthesized in five linear steps and 30% overall yield from the known aldehyde 11. The key step is a one-pot in situ desilylation/Cadiot-Chodkiewicz coupling reaction affording the entriyne unit. The bromoalkyne 6 with an omega-carboxylic acid group was found to undergo a copper-catalyzed cross-coupling reaction producing the desired diyne intermediate 10, while the corresponding omega-ester bromoalkyne 14 failed to couple with triethylsilylacetylene under a variety of conditions.

  6. PERSISTENT CURRENT EFFECT IN 15-16 T NB3SN ACCELERATOR DIPOLES AND ITS CORRECTION

    Energy Technology Data Exchange (ETDEWEB)

    Kashikhin, V. V. [Fermilab; Zlobin, A. V. [Fermilab

    2016-11-08

    Nb3Sn magnets with operating fields of 15-16 T are considered for the LHC Energy Doubler and a future Very High Energy pp Collider. Due to large coil volume, high critical current density and large superconducting (SC) filament size the persistent current effect is very large in Nb3Sn dipoles al low fields. This paper presents the results of analysis of the persistent current effect in the 15 T Nb3Sn dipole demonstrator being developed at FNAL, and describes different possibilities of its correction including passive SC wires, iron shims and coil geometry.

  7. Hematology and serum clinical chemistry reference intervals for free-ranging Scandinavian gray wolves (Canis lupus).

    Science.gov (United States)

    Thoresen, Stein I; Arnemo, Jon M; Liberg, Olof

    2009-06-01

    Scandinavian free-ranging wolves (Canis lupus) are endangered, such that laboratory data to assess their health status is increasingly important. Although wolves have been studied for decades, most biological information comes from captive animals. The objective of the present study was to establish reference intervals for 30 clinical chemical and 8 hematologic analytes in Scandinavian free-ranging wolves. All wolves were tracked and chemically immobilized from a helicopter before examination and blood sampling in the winter of 7 consecutive years (1998-2004). Seventy-nine blood samples were collected from 57 gray wolves, including 24 juveniles (24 samples), 17 adult females (25 samples), and 16 adult males (30 samples). Whole blood and serum samples were stored at refrigeration temperature for 1-3 days before hematologic analyses and for 1-5 days before serum biochemical analyses. Reference intervals were calculated as 95% confidence intervals except for juveniles where the minimum and maximum values were used. Significant differences were observed between adult and juvenile wolves for RBC parameters, alkaline phosphatase and amylase activities, and total protein, albumin, gamma-globulins, cholesterol, creatinine, calcium, chloride, magnesium, phosphate, and sodium concentrations. Compared with published reference values for captive wolves, reference intervals for free-ranging wolves reflected exercise activity associated with capture (higher creatine kinase activity, higher glucose concentration), and differences in nutritional status (higher urea concentration).

  8. Natural gels: crystal-chemistry of short range ordered components in Al, Fe, and Si systems

    Energy Technology Data Exchange (ETDEWEB)

    Ildefonse, Ph.; Calas, G. [Paris-6 et 7 Univ. and IPGP, Lab. de Mineralogie-Cristallographie, UA CNRS 09, 75 (France)

    1997-07-01

    In this review, the most important inorganic natural gels are presented: opal, aluminosilicate (allophanes) and hydrous iron oxides and silicates. It is demonstrated that natural gels are ordered at the atomic scale. In allophanes, Al is distributed between octahedral and tetrahedral sites. The amount of Al increases as Al/Si ratio decreases. Si-rich allophane have a local structure around Al and Si very different of that is known in kaolinite or halloysite. Transformation of Si-rich allophanes to crystallized minerals implies dissolution-recrystallization processes. On the contrary, in iron silicate with Fe/Si = 0.72, Si and Fe environments are close to those found in nontronite. The gel transformation to Fe-smectite may occur by long range ordering during ageing. In ferric silicate gels, the similarity of local structure around Fe in poorly ordered precursors and what is known in crystallized minerals suggests a solid transformation during ageing. This difference between iron and aluminium is mainly due to the ability of Al to enter both tetrahedral and octahedral sites, while the affinity of iron for octahedral sites is higher at low temperature.

  9. Substitution Structures of Large Molecules and Medium Range Correlations in Quantum Chemistry Calculations

    Science.gov (United States)

    Evangelisti, Luca; Pate, Brooks

    2017-06-01

    A study of the minimally exciting topic of agreement between experimental and measured rotational constants of molecules was performed on a set of large molecules with 16-18 heavy atoms (carbon and oxygen). The molecules are: nootkatone (C_{15}H_{22}O), cedrol (C_{15}H_{26}O), ambroxide (C_{16}H_{28}O), sclareolide (C_{16}H_{22}O_{2}), and dihydroartemisinic acid (C_{15}H_{24}O_{2}). For this set of molecules we obtained 13C-subsitution structures for six molecules (this includes two conformers of nootkatone). A comparison of theoretical structures and experimental substitution structures was performed in the spirit of the recent work of Grimme and Steinmetz.[1] Our analysis focused the center-of-mass distance of the carbon atoms in the molecules. Four different computational methods were studied: standard DFT (B3LYP), dispersion corrected DFT (B3LYP-D3BJ), hybrid DFT with dispersion correction (B2PLYP-D3), and MP2. A significant difference in these theories is how they handle medium range correlation of electrons that produce dispersion forces. For larger molecules, these dispersion forces produce an overall contraction of the molecule around the center-of-mass. DFT poorly treats this effect and produces structures that are too expanded. MP2 calculations overestimate the correction and produce structures that are too compact. Both dispersion corrected DFT methods produce structures in excellent agreement with experiment. The analysis shows that the difference in computational methods can be described by a linear error in the center-of-mass distance. This makes it possible to correct poorer performing calculations with a single scale factor. We also reexamine the issue of the "Costain error" in substitution structures and show that it is significantly larger in these systems than in the smaller molecules used by Costain to establish the error limits. [1] Stefan Grimme and Marc Steinmetz, "Effects of London dispersion correction in density functional theory on

  10. Ionospheric Responses to the July 15 - 16, 2000 Magnetic Storm around Geographic Longitude 121E

    Directory of Open Access Journals (Sweden)

    Yu-Jung Chuo

    2008-01-01

    Full Text Available This study presents observed behavior of ionospheric responses using vertical total electron contents (VTEC and NmF2. The data were collected from global positioning system (GPS networks and ionosondes around the geographic longitude of 121°E from mid- to low-latitudes for the severe magnetic storm on 15 July 2000. The results show that the severe magnetic storm caused significant density depletion and a G-condition occurrence in the western Pacific region on 15 - 16 July 2000. The G-condition is observed on the ionograms at Chung-Li station around 2330 UT on July 15. Furthermore, the variation of the F-peak height (HmF2 at Cebu indicates that a zonal electric field produced an upward drift and enhanced the fountain effect from 1000 UT on July 15. The observation of a G-condition indicates that a storm-induced neutral-wind circulation was the main cause of compositional change; i.e., an increase in the N2/O ratio and its associated loss coefficients that produced a negative storm phase along the chain of geographic longitude 121°E.

  11. Impact of Wide-Ranging Nanoscale Chemistry on Band Structure at Cu(In, Ga)Se2 Grain Boundaries.

    Science.gov (United States)

    Stokes, Adam; Al-Jassim, Mowafak; Diercks, David; Clarke, Amy; Gorman, Brian

    2017-10-26

    The relative chemistry from grain interiors to grain boundaries help explain why grain boundaries may be beneficial, detrimental or benign towards device performance. 3D Nanoscale chemical analysis extracted from atom probe tomography (APT) (10's of parts-per-million chemical sensitivity and sub-nanometer spatial resolution) of twenty grain boundaries in a high-efficiency Cu(In, Ga)Se2 solar cell shows the matrix and alkali concentrations are wide-ranging. The concentration profiles are then related to band structure which provide a unique insight into grain boundary electrical performance. Fluctuating Cu, In and Ga concentrations result in a wide distribution of potential barriers at the valence band maximum (VBM) (-10 to -160 meV) and the conduction band minimum (CBM) (-20 to -70 meV). Furthermore, Na and K segregation is not correlated to hampering donors, (In, Ga)Cu and VSe, contrary to what has been previously reported. In addition, Na and K are predicted to be n-type dopants at grain boundaries. An overall band structure at grain boundaries is presented.

  12. Factor Model of Motor and Functional Readiness of Girls Aged 15-16 Years

    Directory of Open Access Journals (Sweden)

    О. В. Іващенко

    2015-09-01

    Full Text Available Research objective. To define methodological approaches to pedagogical control of dynamics of motor and functional readiness of girls aged 15-16. Research methods. To solve the tasks set, the study used the following methods: analysis of scientific and methodological literature, pedagogical testing and methods of mathematical statistics of data reduction. The testing program consisted of the commonly known tests: jumping with “increases f weight” (number of jumps in the given corridor, evaluation of time parameters of movement (error in re-creating the duration of five-second running in place, evaluation of perception of strength movement parameters (the error in re-creating the efforts is 0.5 of the maximum, shuttle run 4×9 m (s, bending and unbending of arms from the lying position (times, bending and unbending of arms in suspension (times, bent suspension (s, standing long jump (cm. Research results. The girls aged 15 show statistically significantly better readiness by the results of the tests: No. 1 “Jumping with ‘increases of weight’, times”, No. 3 “Bending and unbending of arms from the lying position, times”, No. 5 “Bent suspension, s”, and by the indicators of functional tests (p < 0.05. The most informative indicators for the routine control of the motor readiness of girls aged 15 are the following tests: “Bending and unbending of arms from the lying position” (,951, Ghencea test (,929, “Standing long jump (cm” (,930, “Shuttle run 4×9 m, s” (,911. The most informative indicators for the routine control of the motor readiness of girls aged 16 are the following tests: Ghencea test (,945, “Bending and unbending of arms in suspension” (,883, “Bending and unbending of arms from the lying position” (,823.

  13. HMSRP Hawaiian Monk Seal Blood Values (Establishing hematology and serum chemistry reference ranges for wild Hawaiian Monk Seals)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Hematology and serum chemistry evaluations are essential to a patients comprehensive health exam by providing measures of organ function, blood cell volume and...

  14. Weights, hematology and serum chemistry of free-ranging brown boobies (Sula leucogaster) in Johnston Atoll, Central Pacific

    Science.gov (United States)

    Work, Thierry M.

    1999-01-01

    Hematologic and serum chemistry values are reported for 105 brown boobies (Sula leucogaster) from Johnston Atoll, Central Pacific. Hematocrit, estimated total plasma solids, total and differential white cell counts, serum glucose, calcium, phosphorus, uric acid, total protein, albumin, globulin, aspartate aminotransferase, and creatinine phosphokinase were analyzed. Hematologic and serum chemistry values varied with age and sex. Values were compared with those of red-footed boobies and other tropical and temperate marine pelecaniforms.

  15. Quantitative analysis of terrain units mapped in the northern quarter of Venus from Venera 15/16 data

    Science.gov (United States)

    Schaber, G. G.

    1991-01-01

    The contacts between 34 geological/geomorphic terrain units in the northern quarter of Venus mapped from Venera 15/16 data were digitized and converted to a Sinusoidal Equal-Area projection. The result was then registered with a merged Pioneer Venus/Venera 15/16 altimetric database, root mean square (rms) slope values, and radar reflectivity values derived from Pioneer Venus. The resulting information includes comparisons among individual terrain units and terrain groups to which they are assigned in regard to percentage of map area covered, elevation, rms slopes, distribution of suspected craters greater than 10 km in diameter.

  16. The New Outlook for Science. Science and Belief: from Copernicus to Darwin, Block VI, Units 15-16.

    Science.gov (United States)

    Open Univ., Walton, Bletchley, Bucks (England).

    This text contains units 15-16 in the Open University course, Science and Belief: from Copernicus to Darwin. It is an inter-faculty second level course in the history of science. Unit 15 is concerned with Nature and History and includes uniformitarianism, human history, evolutionism, and Darwinism. Unit objectives, readings, and questions with the…

  17. A bicyclic diterpenoid with a new 15,16-dinorlabdane carbon skeleton from Leonurus japonicus and its coagulant bioactivity.

    Science.gov (United States)

    Peng, Fu; Xiong, Liang; Zhao, Xiao-Mei

    2013-11-11

    A new 15,16-dinorlabdane diterpenoid 1 and a known labdane diterpenoid 2, together with three known ergosterols 3-5, were isolated from the EtOAc-soluble portion of the EtOH extract of Leonurus japonicus. Their structures were elucidated by physical and spectroscopic analysis. Compound 1 showed in vitro coagulant activity in the APTT, PT, TT, and FIB assays.

  18. A Bicyclic Diterpenoid with a New 15,16-Dinorlabdane Carbon Skeleton from Leonurus japonicus and Its Coagulant Bioactivity

    Directory of Open Access Journals (Sweden)

    Xiao-Mei Zhao

    2013-11-01

    Full Text Available A new 15,16-dinorlabdane diterpenoid 1 and a known labdane diterpenoid 2, together with three known ergosterols 3–5, were isolated from the EtOAc-soluble portion of the EtOH extract of Leonurus japonicus. Their structures were elucidated by physical and spectroscopic analysis. Compound 1 showed in vitro coagulant activity in the APTT, PT, TT, and FIB assays.

  19. Belowground Plant–Herbivore Interactions Vary among Climate-Driven Range-Expanding Plant Species with Different Degrees of Novel Chemistry

    Directory of Open Access Journals (Sweden)

    Rutger A. Wilschut

    2017-10-01

    Full Text Available An increasing number of studies report plant range expansions to higher latitudes and altitudes in response to global warming. However, consequences for interactions with other species in the novel ranges are poorly understood. Here, we examine how range-expanding plant species interact with root-feeding nematodes from the new range. Root-feeding nematodes are ubiquitous belowground herbivores that may impact the structure and composition of natural vegetation. Because of their ecological novelty, we hypothesized that range-expanding plant species will be less suitable hosts for root-feeding nematodes than native congeneric plant species. In greenhouse and lab trials we compared nematode preference and performance of two root-feeding nematode species between range-expanding plant species and their congeneric natives. In order to understand differences in nematode preferences, we compared root volatile profiles of all range-expanders and congeneric natives. Nematode preferences and performances differed substantially among the pairs of range-expanders and natives. The range-expander that had the most unique volatile profile compared to its related native was unattractive and a poor host for nematodes. Other range-expanding plant species that differed less in root chemistry from native congeners, also differed less in nematode attraction and performance. We conclude that the three climate-driven range-expanding plant species studied varied considerably in their chemical novelty compared to their congeneric natives, and therefore affected native root-feeding nematodes in species-specific ways. Our data suggest that through variation in chemical novelty, range-expanding plant species may vary in their impacts on belowground herbivores in the new range.

  20. Serum chemistry, hematologic, and post-mortem findings in free-ranging bobcats (Lynx rufus) with notoedric mange.

    Science.gov (United States)

    Serieys, Laurel E K; Foley, Janet; Owens, Sean; Woods, Leslie; Boydston, Erin E; Lyren, Lisa M; Poppenga, Robert H; Clifford, Deana L; Stephenson, Nicole; Rudd, Jaime; Riley, Seth P D

    2013-12-01

    Notoedric mange was responsible for a population decline of bobcats ( Lynx rufus ) in 2 Southern California counties from 2002-2006 and is now reported to affect bobcats in Northern and Southern California. With this study we document clinical laboratory and necropsy findings for bobcats with mange. Bobcats in this study included free-ranging bobcats with mange (n = 34), a control group of free-ranging bobcats without mange (n = 11), and a captive control group of bobcats without mange (n = 19). We used 2 control groups to evaluate potential anomalies due to capture stress or diet. Free-ranging healthy and mange-infected bobcats were trapped or salvaged. Animals were tested by serum biochemistry, complete blood count, urine protein and creatinine, body weight, necropsy, and assessment for anticoagulant rodenticide residues in liver tissue. Bobcats with severe mange were emaciated, dehydrated, and anemic with low serum creatinine, hyperphosphatemia, hypoglycemia, hypernatremia, and hyperchloremia, and sometimes septicemic when compared to control groups. Liver enzymes and leukocyte counts were elevated in free-ranging, recently captured bobcats whether or not they were infested with mange, suggesting capture stress. Bobcats with mange had lower levels of serum cholesterol, albumin, globulin, and total protein due to protein loss likely secondary to severe dermatopathy. Renal insufficiency was unlikely in most cases, as urine protein:creatinine ratios were within normal limits. A primary gastrointestinal loss of protein or blood was possible in a few cases, as evidenced by elevated blood urea nitrogen, anemia, intestinal parasitism, colitis, gastric hemorrhage, and melena. The prevalence of exposure to anticoagulant rodenticides was 100% (n = 15) in bobcats with mange. These findings paint a picture of debilitating, multisystemic disease with infectious and toxic contributing factors that can progress to death in individuals and potential decline in populations.

  1. Serum chemistry, hematologic, and post-mortem findings in free-ranging bobcats (Lynx rufus) with notoedric mange

    Science.gov (United States)

    Serieys, Laurel E.K.; Foley, Janet; Owens, Sean; Woods, Leslie; Boydston, Erin E.; Lyren, Lisa M.; Poppenga, Robert H.; Clifford, Deana L.; Stephenson, Nicole; Rudd, Jaime; Riley, Seth P.D.

    2013-01-01

    Notoedric mange was responsible for a population decline of bobcats (Lynx rufus) in 2 Southern California counties from 2002–2006 and is now reported to affect bobcats in Northern and Southern California. With this study we document clinical laboratory and necropsy findings for bobcats with mange. Bobcats in this study included free-ranging bobcats with mange (n = 34), a control group of free-ranging bobcats without mange (n = 11), and a captive control group of bobcats without mange (n = 19). We used 2 control groups to evaluate potential anomalies due to capture stress or diet. Free-ranging healthy and mange-infected bobcats were trapped or salvaged. Animals were tested by serum biochemistry, complete blood count, urine protein and creatinine, body weight, necropsy, and assessment for anticoagulant rodenticide residues in liver tissue. Bobcats with severe mange were emaciated, dehydrated, and anemic with low serum creatinine, hyperphosphatemia, hypoglycemia, hypernatremia, and hyperchloremia, and sometimes septicemic when compared to control groups. Liver enzymes and leukocyte counts were elevated in free-ranging, recently captured bobcats whether or not they were infested with mange, suggesting capture stress. Bobcats with mange had lower levels of serum cholesterol, albumin, globulin, and total protein due to protein loss likely secondary to severe dermatopathy. Renal insufficiency was unlikely in most cases, as urine protein:creatinine ratios were within normal limits. A primary gastrointestinal loss of protein or blood was possible in a few cases, as evidenced by elevated blood urea nitrogen, anemia, intestinal parasitism, colitis, gastric hemorrhage, and melena. The prevalence of exposure to anticoagulant rodenticides was 100% (n = 15) in bobcats with mange. These findings paint a picture of debilitating, multisystemic disease with infectious and toxic contributing factors that can progress to death in individuals and potential decline in populations.

  2. EFFECTS OF PARTIAL QUANTITATIVE CHANGES IN DYNAMIC POWER AND STATIC FORCE OF ATHLETES AGED 15-16

    Directory of Open Access Journals (Sweden)

    Branimir Mikić

    2013-07-01

    Full Text Available The main goal of this research is to determine the contribution of the exercise equipment and free weights to develop the dynamic power and static power ofa thletes aged 15-16 years. In a sample of 162 subjects (divided into two subgroups-control and experimental group was applied 20 tests for the assessment of dynamic power and static power. T-test results show us statistically significant partial quantitative changes in the studied variables in both subsamples. These changes were in the control group significantly weaker, but in each case statistically significant. Based on these results we conclude that each carefully planned program of activities designed to target kinesiology operators, appropriate scale and intensity of the set based on the results of the test input dijagnostičnog leads to a transformation of the expected effects of the training process.

  3. The effects of organic matter-mineral interactions and organic matter chemistry on diuron sorption across a diverse range of soils.

    Science.gov (United States)

    Smernik, Ronald J; Kookana, Rai S

    2015-01-01

    Sorption of non-ionic organic compounds to soil is usually expressed as the carbon-normalized partition coefficient (KOC), because it is assumed that the main factor that influences the amount sorbed is the organic carbon content of the soil. However, KOC can vary by a factor of at least ten across a range of soils. We investigated two potential causes of variation in diuron KOC - organic matter-mineral interactions and organic matter chemistry - for a diverse set of 34 soils from Sri Lanka, representing a wide range of soil types. Treatment with hydrofluoric acid (HF-treatment) was used to concentrate soil organic matter. HF-treatment increased KOC for the majority of soils (average factor 2.4). We attribute this increase to the blocking of organic matter sorption sites in the whole soils by minerals. There was no significant correlation between KOC for the whole soils and KOC for the HF-treated soils, indicating that the importance of organic matter-mineral interactions varied greatly amongst these soils. There was as much variation in KOC across the HF-treated soils as there was across the whole soils, indicating that the nature of soil organic matter is also an important contributor to KOC variability. Organic matter chemistry, determined by solid-state (13)C nuclear magnetic resonance (NMR) spectroscopy, was correlated with KOC for the HF-treated soils. In particular, KOC increased with the aromatic C content (R=0.64, p=1×10(-6)), and decreased with O-alkyl C (R=-0.32, p=0.03) and alkyl C (R=-0.41, p=0.004) content. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. Use of fake identification to purchase alcohol amongst 15-16 year olds: a cross-sectional survey examining alcohol access, consumption and harm

    National Research Council Canada - National Science Library

    Morleo, Michela; Cook, Penny A; Bellis, Mark A; Smallthwaite, Linda

    2010-01-01

    ... risk of alcohol-related harm. An opportunistic survey of 15-16 year olds (n = 9,833) across North West England was used to examine alcohol consumption, methods of access and related harms experienced...

  5. Prenatal ultrasound exposure and children's school performance at age 15-16: follow-up of a randomized controlled trial.

    Science.gov (United States)

    Stålberg, K; Axelsson, O; Haglund, B; Hultman, C M; Lambe, M; Kieler, H

    2009-09-01

    To evaluate the association between prenatal ultrasound exposure and school performance at 15-16 years of age. The study population consisted of children born to women who participated in a randomized controlled trial on the second-trimester ultrasound examination in Sweden from 1985 to 1987. Information about the children's grades when graduating from primary school and information on socioeconomic factors was obtained from Swedish nationwide registers. Comparisons were made using linear and logistic regression analyses according to randomization to ultrasound, ultrasound exposure in the second trimester and ultrasound exposure at any time during pregnancy. Boys and girls were analyzed separately. Of the 4756 singleton children from the randomized trial, we identified 4458 (94%) in the National School Register. There were no statistically significant differences in school performance for boys or girls according to randomization or exposure to ultrasound in the second trimester. Compared to those who were unexposed, boys exposed to ultrasound at least once at any time during fetal life had a tendency towards lower mean school grades in general (-4.39 points; 95% CI, -9.59 to 0.81 (max possible, 320) points) and in physical education (-0.45 points; 95% CI, -0.91 to 0.01 (max possible, 20) points), but the differences did not reach significance. In general, routine ultrasound examination in the second trimester had no effect on overall school performance in teenagers.

  6. [Self-medication with over-the-counter analgesics among 15-16 year-old teenagers].

    Science.gov (United States)

    Lagerløv, Per; Holager, Tanja; Helseth, Sølvi; Rosvold, Elin O

    2009-08-13

    OTC analgesics were released for sale outside pharmacies in Norway in 2003. This study assesses indications and frequency of use of these drugs among 15-16 year-old teenagers in Norway after 2003. We developed a questionnaire, which contained 65 questions with one or more response options. This was given to all pupils in the final grade at six junior high schools in a town with 60,000 inhabitants (Drammen). 367 of 626 (58.6 %) pupils participated. 50 % of the boys and 71 % of the girls had used OTC analgesics during the last four weeks; 26 % of them on a daily or weekly basis. Girls experienced episodes of pain more frequently than boys, but the proportion of episodes treated with analgesics did not differ between the sexes. Headache and muscle pain were common. Half of those with severe headache/migraine used OTC analgesics on a daily or weekly basis. The teenagers reported several reasons for experiencing pain and discomfort, such as long time spent in front of various screens, tight time schedules with physical exercise and friends, drinking too little and much noise in the classroom. Use of OTC analgesics has increased considerably among Norwegian teenagers. Drug-induced headache may occur as an adverse event. If more effort is made to improve life situations that adolescents perceive as painful and a cause of discomfort, the need for OTC analgesics may be reduced.

  7. Modern Trends in Inorganic Chemistry

    Indian Academy of Sciences (India)

    Unknown

    projections of research in frontier areas of inorganic chemistry, includ- ing organometallics, bio-inorganic chemistry, catalysis and materials chemistry. We do hope that the wide range of topics covered in this Issue reflect the current trends of research in inorganic chemistry in India and prac- titioners of inorganic chemistry ...

  8. Air quality at a snowmobile staging area and snow chemistry on and off trail in a Rocky Mountain subalpine forest, Snowy Range, Wyoming.

    Science.gov (United States)

    Musselman, Robert C; Korfmacher, John L

    2007-10-01

    A study was begun in the winter of 2000-2001 and continued through the winter of 2001-2002 to examine air quality at the Green Rock snowmobile staging area at 2,985 m elevation in the Snowy Range of Wyoming. The study was designed to evaluate the effects of winter recreation snowmobile activity on air quality at this high elevation site by measuring levels of nitrogen oxides (NO( x ), NO), carbon monoxide (CO), ozone (O(3)) and particulate matter (PM(10) mass). Snowmobile numbers were higher weekends than weekdays, but numbers were difficult to quantify with an infrared sensor. Nitrogen oxides and carbon monoxide were significantly higher weekends than weekdays. Ozone and particulate matter were not significantly different during the weekend compared to weekdays. Air quality data during the summer was also compared to the winter data. Carbon monoxide levels at the site were significantly higher during the winter than during the summer. Nitrogen oxides and particulates were significantly higher during the summer compared to winter. Nevertheless, air pollutants were well dispersed and diluted by strong winds common at the site, and it appears that snowmobile emissions did not have a significant impact on air quality at this high elevation ecosystem. Pollutant concentrations were generally low both winter and summer. In a separate study, water chemistry and snow density were measured from snow samples collected on and adjacent to a snowmobile trail. Snow on the trail was significantly denser and significantly more acidic with significantly higher concentrations of sodium, ammonium, calcium, magnesium, fluoride, and sulfate than in snow off the trail. Snowmobile activity had no effect on nitrate levels in snow.

  9. 7,8,15,16-tetraoxa-dispiro[5.2.5.2]hexadecane-3-carboxylic acid derivatives and their antimalarial activity

    Directory of Open Access Journals (Sweden)

    BOGDAN SOLAJA

    2004-11-01

    Full Text Available Several C2 symmetrical mixed tetraoxanes were prepared starting from a gemdihydroperoxide and a ketone. The obtained tetraoxanes showed pronounced antimalarial activity against P. falciparum chloroquine resistant W2 and chloroquine susceptible D6 strains, with N-(2-dimethylaminoethyl-7,8,15,16-tetraoxa-dispiro[5.2.5.2] hexadecane-3-carboxamide being as active as artemisinin.

  10. Use of fake identification to purchase alcohol amongst 15-16 year olds: a cross-sectional survey examining alcohol access, consumption and harm

    National Research Council Canada - National Science Library

    Morleo, Michela; Cook, Penny A; Bellis, Mark A; Smallthwaite, Linda

    2010-01-01

    ...%) of 15-16 year old participants who drank reported having bought their own alcohol. One seventh (14.9%) of these owned at least one form of fake identification for which by far the most common purchase method was online...

  11. Does Parental Divorce Increase Risk Behaviors among 15/16 and 18/19 year-old Adolescents? A Study from Oslo, Norway

    National Research Council Canada - National Science Library

    Zeratsion, Henok; Bjertness, Cecilie B; Lien, Lars; Haavet, Ole R; Dalsklev, Madeleine; Halvorsen, Jon A; Bjertness, Espen; Claussen, Bjørgulf

    2014-01-01

    ...) were conducted using data from two Young-HUBRO surveys in Oslo, Norway. All 15/16 year-old 10(th) grade students who participated in the first survey in the school year 2000/01 were followed-up in 2004 when they were 18/19 year-olds...

  12. Numerical simulations on the effect of aerosols on tropospheric chemistry and range of sight; Numerische Simulationen zur Wirkung des Aerosols auf die troposphaerische Chemie und die Sichtweite

    Energy Technology Data Exchange (ETDEWEB)

    Riemer, N.

    2002-05-01

    In this study the mesoscale KAMM/DRAS model system was extended by an MADE aerosol module with a view to studying tropospheric aerosols in terms of composition and size distribution in the greatest possible detail. In particular, the MADE aerosol module was supplemented by a routine for soot. This routine involves the parameterisation of the ageing process of soot through coagulation of soot particles with soluble particles and condensation of sulphuric acid on the soot particles. This transforms the soot from an external into an internal mixture and changes its hygroscopic properties. Thus extended the model system was used to study two aspects of the effects of aerosols on the physical and chemical environment of the troposphere. The first of these two tasks was to quantify the influence of heterogeneous hydrolysis of dinitrogen pentoxide (N{sub 2}O{sub 5}) on tropospheric chemistry under summer smog conditions. The second was to study the optical properties of aerosols. The paper shows a way of deriving extinction coefficients from the calculated aerosol distributions. This is then used as a starting point for developing a method for determining range of sight. [German] Das mesoskalige Modellsystem KAMM/DRAIS wird im Rahmen dieser Arbeit um das Aerosolmodul MADE erweitert, um das troposphaerische Aerosol sowohl bezueglich seiner Zusammensetzung als auch bezueglich seiner Groessenverteilung moeglichst detailliert zu behandeln. Insbesondere wird das Aerosolmodul MADE um die Behandlung der Substanz Russ ergaenzt. Hierbei wird der Alterungsprozess von Russ durch Koagulation der Russteilchen mit loeslichen Partikeln und durch Kondensation von Schwefelsaeure auf den Russpartikeln, wodurch der Russ von einer externen in eine interne Mischung uebergeht und seine hygroskopischen Eigenschaften aendert, parametrisiert. Mit dem so erweiterten Modellsystem wird fuer zwei Themenschwerpunkte die Wirkung des Aerosols auf die physikalischen und chemischen Bedingungen in der

  13. 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

  14. Synthesis and biological evaluation of novel 2,4,5-triarylimidazole-1,2,3-triazole derivatives via click chemistry as α-glucosidase inhibitors.

    Science.gov (United States)

    Wang, Guangcheng; Peng, Zhiyun; Wang, Jing; Li, Juan; Li, Xin

    2016-12-01

    A novel series of 2,4,5-triarylimidazole-1,2,3-triazole derivatives were synthesized via copper(I)-catalyzed azide-alkyne click chemistry, and evaluated for their α-glucosidase inhibitory activity. All tested compounds showed potent α-glucosidase inhibitory activity with IC50 ranging from 15.16±0.18 to 48.15±0.37μM, in comparison to the standard drug, acarbose (IC50=817.38±6.27μM). Among all the tested compounds, 5j was found to be the most active compound with IC50 value of 15.16±0.18μM and behaved as a noncompetitive inhibitor with a Ki of 14.78μM. In addition, molecular docking study was carried out to explore the binding interactions of these compounds with α-glucosidase enzyme. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. PENINGKATAN KEPOLARAN ASAM LINOLEAT DALAM BENTUK AMIDA MENJADI N-etanol-9,10,12,13,15,16 HEKSAHIDROKSI OLEIL-AMIDA

    Directory of Open Access Journals (Sweden)

    Daniel Tarigan

    2016-07-01

    Full Text Available Asam linolenat dari minyak nabati diesterifikasi dengan metanol menggunakan katalis asam dan dilanjutkan dengan amidasi dengan etanolamina menghasilkan alkanolamida selanjutnya dilakukan epoksidasi dengan tert-butyl hidroperoksida dan bantuan katalis peroksigenase dipanaskan pada suhu 40oC selama ± 12 jam sambil dialirkan gas Nitrogen UHP 99% untuk menghasilkan senyawa epoksi alkanolamida oktadekanoat campuran yang selanjutnya dihidrolisis dengan HCl 0,1 N untuk menghasilkan senyawa poliol alkanolamida heksahidroksi oktadekanoat. Uji HLB dari surfaktan alkanolamida heksahidroksi oktadekanoat (N-etanol-9,10,12,13,15,16 heksahidroksi oleil amida sebesar 14,13 Oleh karena itu senyawa poliol ini dapat digunakan sebagai pengemulsi sistem o/w. Seluruh hasil reaksi dikonfirmasikan secara analisis spektroskopi FT-IR, 1H-NMR, GC-MS dan analisis KLT sesuai dengan keperluan.    Kata kunci: Asam linolenat, N-etanol-9,10,12,13,15,16 heksahidroksi oleil amida dan esterifikasi

  16. Does Parental Divorce Increase Risk Behaviors among 15/16 and 18/19 year-old Adolescents? A Study from Oslo, Norway.

    Science.gov (United States)

    Zeratsion, Henok; Bjertness, Cecilie B; Lien, Lars; Haavet, Ole R; Dalsklev, Madeleine; Halvorsen, Jon A; Bjertness, Espen; Claussen, Bjørgulf

    2014-01-01

    Several studies have reported an increase in risk behaviors among adolescents after experience of parental divorce. The aim of the study was to investigate whether parental divorce is associated with risk behavior among adolescents independent of mental health problems, first when early divorce was experienced, and second after experience of late parental divorce. One prospective (n=1861) and one cross-sectional study (n=2422) were conducted using data from two Young-HUBRO surveys in Oslo, Norway. All 15/16 year-old 10(th) grade students who participated in the first survey in the school year 2000/01 were followed-up in 2004 when they were 18/19 year-olds. The follow-up rate was 68%. The prospective study investigated the influence of late parental divorce that occurred between the age of 15/16 and 18/19. In the cross-sectional study we focused on early parental divorce that occurred before the participants were 15/16 year-old. In the prospective study we could not discern a significant association between experiencing late parental divorce and an increase in risk behaviors among 18/19 year-old adolescents. In the cross-sectional study parental divorce was significantly associated with cigarette smoking and using doping agents. Parental divorce that occurs when the children of divorced parents are 15/16 year-old or younger is associated with an increase in cigarette smoking and use of doping agents. However, no evidence of significant association is found between experience of late parental divorce and risk behaviors in late adolescence.

  17. Fuel gas production from animal and agricultural residues and biomass. Quarterly coordination meeting, March 15-16, 1979, Tampa, Florida. Third quarterly progress report

    Energy Technology Data Exchange (ETDEWEB)

    Wise, D L; Ashare, E; Wentworth, R L

    1979-04-24

    The eleventh quarterly coordination meeting of the methane production group of the Fuels From Biomass Systems Branch, US Department of Energy was held at Tampa, Florida, March 15-16, 1979. Progress reports were presented by the contractors and a site visit was made to Kaplan Industries, Bartow, Florida to see the Hamilton Standard demonstration facility for digestion of environmental feedlot residue to methane. A meeting agenda, a list of attendees, and progress reports are presented.

  18. 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.

  19. 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.

  20. Use of fake identification to purchase alcohol amongst 15-16 year olds: a cross-sectional survey examining alcohol access, consumption and harm

    Directory of Open Access Journals (Sweden)

    Smallthwaite Linda

    2010-06-01

    Full Text Available Abstract Background Despite legislation and enforcement activities to prevent underage access to alcohol, underage individuals continue to be able to access alcohol and to do so at levels which put them at significant risk of alcohol-related harm. Methods An opportunistic survey of 15-16 year olds (n = 9,833 across North West England was used to examine alcohol consumption, methods of access and related harms experienced (such as regretted sex. Associations between these were analysed using chi square and logistic regression techniques. Results Over a quarter (28.3% of 15-16 year old participants who drank reported having bought their own alcohol. One seventh (14.9% of these owned at least one form of fake identification for which by far the most common purchase method was online. Logistic regression analyses showed that those who owned fake identification were significantly more likely to be male (AOR = 2.0; 95% CI = 1.7-2.5; P £30 with those who received ≤ £10: AOR = 3.7; 95% CI = 2.9-4.9; P Conclusions Young people (aged 15-16 years who have access to fake identification are at a particularly high risk of reporting hazardous alcohol consumption patterns and related harm. Owning fake identification should be considered a risk factor for involvement in risky drinking behaviours. Information on these hazards should be made available to schools and professionals in health, social and judicial services, along with advice on how to best to work with those involved.

  1. Unusual Chemistry of the Miocene Central Basin and Range: zr and LREE Enriched Mafic Rocks of the Lucy Gray and Mccullough Mountains, Nevada

    Science.gov (United States)

    Johnsen, R. L.; Smith, E. I.

    2011-12-01

    The dominantly intermediate mid-Miocene (ca. 16-12 Ma) volcanic section in the northern and central McCullough Range of the Basin and Range Province, Nevada, typifies igneous rocks in similar-aged, adjacent mountain ranges (e.g., the Highland Range and the Eldorado Mountains). Calc-alkaline andesite to dacite domes, flows, and related pyroclastic materials dominate while rhyolite and basalt are volumetrically minor constituents. These rocks have the typical "arc" chemical signature prevalent in subduction zones and in pre-extensional Basin and Range igneous rocks (Zr, Nb, Ti depletions, Beer Bottle Pass Granite; and, perhaps most intriguing, 3) the ~1.4 Ga Sulphide Queen carbonatite and age-equivalent shonkinite, syenite, and granite of Mountain Pass. Shonkinites are well known for their extreme LREE enrichment and these in particular contain up to 1000 ppm Zr as well. Could a small amount of contamination of a highly enriched crustal rock such as shonkinite or syenite with a more normal OIB-like basaltic melt account for the odd character of these Miocene rocks? Or is it more likely indicative of an unusually enriched LM source?

  2. 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.

  3. 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....

  4. Discussing epigenetics in Southern California: a report from the International Symposium on Epigenetic Control and Cellular Plasticity, UCI, December 15-16, 2011.

    Science.gov (United States)

    Rattner, Barbara P

    2012-04-01

    With the goal of discussing how epigenetic control and chromatin remodeling contribute to the various processes that lead to cellular plasticity and disease, this symposium marks the collaboration between the Institut National de la Santé et de la Recherche Médicale (INSERM) in France and the University of California, Irvine (UCI). Organized by Paolo Sassone-Corsi (UCI) and held at the Beckman Center of the National Academy of Sciences at the UCI campus December 15-16, 2011, this was the first of a series of international conferences on epigenetics dedicated to the scientific community in Southern California. The meeting also served as the official kick off for the newly formed Center for Epigenetics and Metabolism at the School of Medicine, UCI (http://cem.igb.uci.edu).

  5. Can use of healthcare services among 15-16-year-olds predict an increased level of high school dropout? A longitudinal community study.

    Science.gov (United States)

    Homlong, Lisbeth; Rosvold, Elin O; Haavet, Ole R

    2013-09-19

    To study associations between healthcare seeking in 15-16-year-olds and high school dropout 5 years later. Longitudinal community study. Data from a comprehensive youth health survey conducted in 2000-2004, linked to data from national registries up to 2010. 13 964 10th grade secondary school students in six Norwegian counties. Logistic regression was used to compute ORs for high school dropout. The total proportion of students not completing high school 5 years after registering was 29% (girls 24%, boys 34%). Frequent attenders to school health services and youth health clinics at age 15-16 years had a higher dropout rate (37/48% and 45/71%), compared with those with no or moderate use. Adolescents referred to mental health services were also more likely to drop out (47/62%). Boys with moderate use of a general practitioner (GP) had a lower dropout rate (30%). A multiple logistic regression analysis, in which we adjusted for selected health indicators and sociodemographic background variables, revealed that seeking help from the youth health clinic and consulting mental health services, were associated with increased level of high school dropout 5 years later. Frequent attenders (≥4 contacts) had the highest odds of dropping out. Yet, boys who saw a GP and girls attending the school health services regularly over the previous year were less likely than their peers to drop out from high school. Adolescents who seek help at certain healthcare services can be at risk of dropping out of high school later. Health workers should pay particular attention to frequent attenders and offer follow-up when needed. However, boys who attended a GP regularly were more likely to continue to high school graduation, which may indicate a protective effect of having a regular and stable relationship with a GP.

  6. Comparison of lodgepole and jack pine resin chemistry: implications for range expansion by the mountain pine beetle, Dendroctonus ponderosae (Coleoptera: Curculionidae

    Directory of Open Access Journals (Sweden)

    Erin L. Clark

    2014-02-01

    Full Text Available The mountain pine beetle, Dendroctonus ponderosae, is a significant pest of lodgepole pine in British Columbia (BC, where it has recently reached an unprecedented outbreak level. Although it is native to western North America, the beetle can now be viewed as a native invasive because for the first time in recorded history it has begun to reproduce in native jack pine stands within the North American boreal forest. The ability of jack pine trees to defend themselves against mass attack and their suitability for brood success will play a major role in the success of this insect in a putatively new geographic range and host. Lodgepole and jack pine were sampled along a transect extending from the beetle’s historic range (central BC to the newly invaded area east of the Rocky Mountains in north-central Alberta (AB in Canada for constitutive phloem resin terpene levels. In addition, two populations of lodgepole pine (BC and one population of jack pine (AB were sampled for levels of induced phloem terpenes. Phloem resin terpenes were identified and quantified using gas chromatography. Significant differences were found in constitutive levels of terpenes between the two species of pine. Constitutive α-pinene levels – a precursor in the biosynthesis of components of the aggregation and antiaggregation pheromones of mountain pine beetle – were significantly higher in jack pine. However, lower constitutive levels of compounds known to be toxic to bark beetles, e.g., 3-carene, in jack pine suggests that this species could be poorly defended. Differences in wounding-induced responses for phloem accumulation of five major terpenes were found between the two populations of lodgepole pine and between lodgepole and jack pine. The mountain pine beetle will face a different constitutive and induced phloem resin terpene environment when locating and colonizing jack pine in its new geographic range, and this may play a significant role in the ability of the

  7. Processes Governing Alkaline Groundwater Chemistry within a Fractured Rock (Ophiolitic Mélange Aquifer Underlying a Seasonally Inhabited Headwater Area in the Aladağlar Range (Adana, Turkey

    Directory of Open Access Journals (Sweden)

    Cüneyt Güler

    2017-01-01

    Full Text Available The aim of this study was to investigate natural and anthropogenic processes governing the chemical composition of alkaline groundwater within a fractured rock (ophiolitic mélange aquifer underlying a seasonally inhabited headwater area in the Aladağlar Range (Adana, Turkey. In this aquifer, spatiotemporal patterns of groundwater flow and chemistry were investigated during dry (October 2011 and wet (May 2012 seasons utilizing 25 shallow hand-dug wells. In addition, representative samples of snow, rock, and soil were collected and analyzed to constrain the PHREEQC inverse geochemical models used for simulating water-rock interaction (WRI processes. Hydrochemistry of the aquifer shows a strong interseasonal variability where Mg–HCO3 and Mg–Ca–HCO3 water types are prevalent, reflecting the influence of ophiolitic and carbonate rocks on local groundwater chemistry. R-mode factor analysis of hydrochemical data hints at geochemical processes taking place in the groundwater system, that is, WRI involving Ca- and Si-bearing phases; WRI involving amorphous oxyhydroxides and clay minerals; WRI involving Mg-bearing phases; and atmospheric/anthropogenic inputs. Results from the PHREEQC modeling suggested that hydrogeochemical evolution is governed by weathering of primary minerals (calcite, chrysotile, forsterite, and chromite, precipitation of secondary minerals (dolomite, quartz, clinochlore, and Fe/Cr oxides, atmospheric/anthropogenic inputs (halite, and seasonal dilution from recharge.

  8. What Are the Barriers Which Discourage 15-16 Year-Old Girls from Participating in Team Sports and How Can We Overcome Them?

    Science.gov (United States)

    Wetton, Abigail R.; Jones, Angela R.; Pearce, Mark S.

    2013-01-01

    Given the clear benefits of regular physical activity (such as reduced risks of cardiovascular disease and obesity, as well as other benefits including those related to mental health), exploration of the reasons that adolescent girls give for not taking part in team sports may be particularly valuable for enhancing later rates of participation. We combined questionnaires (n = 60) and semistructured interviews (n = 6) to assess the barriers that prevent 15-16-year-old girls from participating in extracurricular team games and what can be done to overcome these barriers and improve physical activity levels. Four barriers became prominent as to why girls in this sample do not participate: Internal Factors, Existing Stereotypes, Other Hobbies and Teachers. Methods to overcome these barriers were identified; changing teachers' attitudes and shifting the media's focus away from male sport. Following the successful summer Olympics and Paralympics in the UK, and the resulting positive focus on some of the nation's female athletes, a shift in focus may be possible. However, this needs to be maintained to allow girls more opportunities, role models and motivation to participate in sport. PMID:24073416

  9. What are the barriers which discourage 15-16 year-old girls from participating in team sports and how can we overcome them?

    Science.gov (United States)

    Wetton, Abigail R; Radley, Rebecca; Jones, Angela R; Pearce, Mark S

    2013-01-01

    Given the clear benefits of regular physical activity (such as reduced risks of cardiovascular disease and obesity, as well as other benefits including those related to mental health), exploration of the reasons that adolescent girls give for not taking part in team sports may be particularly valuable for enhancing later rates of participation. We combined questionnaires (n = 60) and semistructured interviews (n = 6) to assess the barriers that prevent 15-16-year-old girls from participating in extracurricular team games and what can be done to overcome these barriers and improve physical activity levels. Four barriers became prominent as to why girls in this sample do not participate: Internal Factors, Existing Stereotypes, Other Hobbies and Teachers. Methods to overcome these barriers were identified; changing teachers' attitudes and shifting the media's focus away from male sport. Following the successful summer Olympics and Paralympics in the UK, and the resulting positive focus on some of the nation's female athletes, a shift in focus may be possible. However, this needs to be maintained to allow girls more opportunities, role models and motivation to participate in sport.

  10. What Are the Barriers Which Discourage 15-16 Year-Old Girls from Participating in Team Sports and How Can We Overcome Them?

    Directory of Open Access Journals (Sweden)

    Abigail R. Wetton

    2013-01-01

    Full Text Available Given the clear benefits of regular physical activity (such as reduced risks of cardiovascular disease and obesity, as well as other benefits including those related to mental health, exploration of the reasons that adolescent girls give for not taking part in team sports may be particularly valuable for enhancing later rates of participation. We combined questionnaires ( and semistructured interviews ( to assess the barriers that prevent 15-16-year-old girls from participating in extracurricular team games and what can be done to overcome these barriers and improve physical activity levels. Four barriers became prominent as to why girls in this sample do not participate: Internal Factors, Existing Stereotypes, Other Hobbies and Teachers. Methods to overcome these barriers were identified; changing teachers’ attitudes and shifting the media’s focus away from male sport. Following the successful summer Olympics and Paralympics in the UK, and the resulting positive focus on some of the nation’s female athletes, a shift in focus may be possible. However, this needs to be maintained to allow girls more opportunities, role models and motivation to participate in sport.

  11. Biological maturation, morphology, fitness, and motor coordination as part of a selection strategy in the search for international youth soccer players (age 15-16 years).

    Science.gov (United States)

    Vandendriessche, Joric B; Vaeyens, Roel; Vandorpe, Barbara; Lenoir, Matthieu; Lefevre, Johan; Philippaerts, Renaat M

    2012-01-01

    We report the morphology (height, weight, body fat, body mass index), fitness (strength, speed, agility, flexibility), and soccer-specific (dribbling) and non-specific motor coordination skills (Körper KoordinationsTest für Kinder; KTK) of 78 Belgian international youth soccer players aged 15-16 years with varying biological maturity status. The more mature players (U16 and U17) possessed higher morphological measures and outperformed their later maturing peers (U16 Futures and U17 Futures) on almost all fitness tests. However, soccer-specific and non-specific motor coordination tests did not distinguish the more mature players from the later maturing players in both age groups. When adjusted for the confounder (age at peak height velocity), multivariate analysis of covariance revealed that several morphology- and fitness-related parameters did not differ between selection groups, again in both age groups. These findings indicate that biological maturation affects morphology and fitness more so than motor coordination skills. In conclusion, to prevent the dropout of promising late maturing players, we suggest avoiding one-dimensional approaches and to include measures of biological maturity status as well as maturity independent performance tests during the talent identification and selection process.

  12. Chemistry Technology

    Data.gov (United States)

    Federal Laboratory Consortium — Chemistry technology experts at NCATS engage in a variety of innovative translational research activities, including:Design of bioactive small molecules.Development...

  13. 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...

  14. Psychosocial vulnerability underlying four common unhealthy behaviours in 15-16-year-old Swedish adolescents: a cross-sectional study.

    Science.gov (United States)

    Paulsson-Do, Ulrica; Edlund, Birgitta; Stenhammar, Christina; Westerling, Ragnar

    2017-12-15

    Factors that influence unhealthy behaviours in adolescents may have different impacts in different sociocultural settings. There is lack of research on the association between psychosocial vulnerability and unhealthy behaviours in adolescents, particularly outside the United States. The aim was to investigate both direct and indirect relationships between psychosocial conditions (subjective well-being, social relationships and self-esteem) and four health-related behaviours (smoking, alcohol consumption, meal frequency and physical activity) in Swedish adolescents aged 15-16 years. Socio-demographic variables (socio-economic status, gender and age) were also investigated. To study these associations, a hypothesised model was tested using structural equation modelling. In the hypothesised model, interrelated psychosocial conditions (low well-being, poor social relationships and low self-esteem) and socio-demographic factors (low self-perceived socio-economic status, being female and higher age) together represented a vulnerability underlying smoking, alcohol consumption, irregular meal frequency and low level of physical activity. In this cross-sectional study, self-report questionnaires were used to collect data from 492 adolescents. Hypothesised pathways between psychosocial conditions, socio-demographic factors and the four unhealthy behaviours were confirmed. Low well-being was strongly associated with unhealthy behaviours, and poor social relationships showed a strong indirect association with the unhealthy behaviours. Low self-esteem, low self-perceived socio-economic status and female gender were also vulnerability factors for the unhealthy behaviours. Vulnerability for four common unhealthy behaviours was found in Swedish adolescents. This study presents the interrelationships of psychosocial and socio-demographic factors and how they were related with unhealthy behaviours. The results bring new insight into how psychosocial factors are related to unhealthy

  15. 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,

  16. 15, 16-Dihydrotanshinone I Inhibits Hemangiomas through Inducing Pro-apoptotic and Anti-angiogenic Mechanisms in Vitro and in Vivo

    Directory of Open Access Journals (Sweden)

    Yihong Cai

    2018-01-01

    Full Text Available Infantile hemangioma (IH is a common and benign vascular neoplasms, which has a high incidence in children. Although IH is benign, some patients experience complications such as pain, functional impairment, and permanent disfigurement. Treatment options for IH include corticosteroids, surgery, vincristine, interferon or cyclophosphamide. However, none of these modalities are ideal due to restrictions or potential serious side effects. There is thus a great need to explore novel treatments for IH with less side effects. Angiogenesis, vasculogenesis and tumorigenesis are the main features of IH. Tanshen is mostly used in Chinese traditional medicine to treat hematological abnormalities. Therefore, the aim of our study was to evaluate anti-proliferation and anti-angiogenesis effects on hemangiomas cells by extracted Tanshen compounds compared with propranolol, the first-line treatment for IH currently, both in vitro and in vivo. Cell viability, apoptosis, protein expression and anti-angiogenesis were analyzed by CCK8, Annexin V staining, Western blot and tube formation, respectively. The anti-tumor activity in vivo was evaluated using a mouse xenograft model. Fourteen major compounds extracting from Tanshen were screened for their ability to inhibit hemangiomas cells. Of the 14 compounds investigated, 15,16-Dihydrotanshinone I (DHTS was the most potent modulator of EOMA cell biology. DHTS could significantly decrease EOMA cells proliferation by inducing cell apoptosis, which is much more efficient than propranolol in vitro. DHTS increased the expression of several apoptosis-related proteins, including caspase9, caspase3, PARP, AIF, BAX, cytochrome c, caspase8 and FADD and significantly inhibited angiogenesis, as indicated by reduced tube formation and diminished expression of vascular endothelial cell growth factor receptor 2 and matrix metalloproteinase 9. In nude mice xenograft experiment, DHTS (10 mg/kg could significantly inhibit the tumor

  17. 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...

  18. Nuclear Chemistry.

    Science.gov (United States)

    Chemical and Engineering News, 1979

    1979-01-01

    Provides a brief review of the latest developments in nuclear chemistry. Nuclear research today is directed toward increased activity in radiopharmaceuticals and formation of new isotopes by high-energy, heavy-ion collisions. (Author/BB)

  19. Green Chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Collison, Melanie

    2011-05-15

    Green chemistry is the science of chemistry used in a way that will not use or create hazardous substances. Dr. Rui Resendes is working in this field at GreenCentre Canada, an offshoot of PARTEQ Innovations in Kingston, Ontario. GreenCentre's preliminary findings suggest their licensed product {sup S}witchable Solutions{sup ,} featuring 3 classes of solvents and a surfactant, may be useful in bitumen oil sands extraction.

  20. Identifying Students' Misconceptions about Nuclear Chemistry: A Study of Turkish High School Students

    Science.gov (United States)

    Nakiboglu, Canan; Tekin, Berna Bulbul

    2006-01-01

    This study represents the first attempt to elucidate and detail the types of misconceptions high school students hold relating to basic concepts and topics of nuclear chemistry. A diagnostic multiple-choice test was administered to 157 tenth-grade students (15-16 years old) and the data were analyzed. The results show that high school students…

  1. News: Green Chemistry & Technology

    Science.gov (United States)

    A series of 21 articles focused on different features of green chemistry in a recent issue of Chemical Reviews. Topics extended over a wide range to include the design of sustainable synthetic processes to biocatalysis. A selection of perspectives follows as part of this colu

  2. Dynamic Combinatorial Chemistry

    DEFF Research Database (Denmark)

    Lisbjerg, Micke

    This thesis is divided into seven chapters, which can all be read individually. The first chapter, however, contains a general introduction to the chemistry used in the remaining six chapters, and it is therefore recommended to read chapter one before reading the other chapters. Chapter 1...... is a general introductory chapter for the whole thesis. The history and concepts of dynamic combinatorial chemistry are described, as are some of the new and intriguing results recently obtained. Finally, the properties of a broad range of hexameric macrocycles are described in detail. Chapter 2 gives...

  3. Radiation Chemistry

    Science.gov (United States)

    Wojnárovits, L.

    Ionizing radiation causes chemical changes in the molecules of the interacting medium. The initial molecules change to new molecules, resulting in changes of the physical, chemical, and eventually biological properties of the material. For instance, water decomposes to its elements H2 and O2. In polymers, degradation and crosslinking take place. In biopolymers, e.g., DNS strand breaks and other alterations occur. Such changes are to be avoided in some cases (radiation protection), however, in other cases they are used for technological purposes (radiation processing). This chapter introduces radiation chemistry by discussing the sources of ionizing radiation (radionuclide sources, machine sources), absorption of radiation energy, techniques used in radiation chemistry research, and methods of absorbed energy (absorbed dose) measurements. Radiation chemistry of different classes of inorganic (water and aqueous solutions, inorganic solids, ionic liquids (ILs)) and organic substances (hydrocarbons, halogenated compounds, polymers, and biomolecules) is discussed in concise form together with theoretical and experimental backgrounds. An essential part of the chapter is the introduction of radiation processing technologies in the fields of polymer chemistry, food processing, and sterilization. The application of radiation chemistry to nuclear technology and to protection of environment (flue gas treatment, wastewater treatment) is also discussed.

  4. Polymer Chemistry

    Science.gov (United States)

    Williams, Martha; Roberson, Luke; Caraccio, Anne

    2010-01-01

    This viewgraph presentation describes new technologies in polymer and material chemistry that benefits NASA programs and missions. The topics include: 1) What are Polymers?; 2) History of Polymer Chemistry; 3) Composites/Materials Development at KSC; 4) Why Wiring; 5) Next Generation Wiring Materials; 6) Wire System Materials and Integration; 7) Self-Healing Wire Repair; 8) Smart Wiring Summary; 9) Fire and Polymers; 10) Aerogel Technology; 11) Aerogel Composites; 12) Aerogels for Oil Remediation; 13) KSC's Solution; 14) Chemochromic Hydrogen Sensors; 15) STS-130 and 131 Operations; 16) HyperPigment; 17) Antimicrobial Materials; 18) Conductive Inks Formulations for Multiple Applications; and 19) Testing and Processing Equipment.

  5. Food carbohydrate chemistry

    National Research Council Canada - National Science Library

    Wrolstad, R. E

    2012-01-01

    .... Now in Food Carbohydrate Chemistry, author Wrolstad emphasizes the application of carbohydrate chemistry to understanding the chemistry, physical and functional properties of food carbohydrates...

  6. Confectionary Chemistry.

    Science.gov (United States)

    Levine, Elise Hilf

    1996-01-01

    Presents activities and demonstrations that enable teachers to use various types of confections as tactile experiences to spark chemistry students' interest and generate enthusiasm for learning. Presents uses of candy in teaching about atomic structure, spontaneous nuclear decay, chemical formulas, fractoluminescence, the effect of a molecular…

  7. Chemistry Notes.

    Science.gov (United States)

    School Science Review, 1983

    1983-01-01

    Presents chemistry experiments, laboratory procedures, demonstrations, and classroom materials/activities. These include: experiments on colloids, processing of uranium ore, action of heat on carbonates; color test for phenols and aromatic amines; solvent properties of non-electrolytes; stereoscopic applications/methods; a valency balance;…

  8. 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

  9. The association between weekly hours of physical activity and mental health: a three-year follow-up study of 15-16-year-old students in the city of Oslo, Norway.

    Science.gov (United States)

    Sagatun, Aase; Søgaard, Anne Johanne; Bjertness, Espen; Selmer, Randi; Heyerdahl, Sonja

    2007-07-12

    Mental health problems are a worldwide public health burden. The literature concerning the mental health benefits from physical activity among adults has grown. Adolescents are less studied, and especially longitudinal studies are lacking. This paper investigates the associations between weekly hours of physical activity at age 15-16 and mental health three years later. Longitudinal self-reported health survey. The baseline study consisted of participants from the youth section of the Oslo Health Study, carried out in schools in 2000-2001 (n = 3811). The follow-up in 2003-2004 was conducted partly at school and partly through mail. A total of 2489 (1112 boys and 1377 girls) participated in the follow-up. Mental health was measured by the Strengths and Difficulties Questionnaire with an impact supplement. Physical activity was measured by a question on weekly hours of physical activity outside of school, defined as exertion 'to an extent that made you sweat and/or out of breath'. Adjustments were made for well-documented confounders and mental health at baseline. In boys, the number of hours spent on physical activity per week at age 15-16 was negatively associated with emotional symptoms [B (95%CI) = -0.09 (-0.15, -0.03)] and peer problems [B (95%CI) = -0.08 (-0.14, -0.03)] at age 18-19 after adjustments. In girls, there were no significant differences in SDQ subscales at age 18-19 according to weekly hours of physical activity at age 15-16 after adjustments. Boys and girls with five to seven hours of physical activity per week at age 15-16 had the lowest mean scores for total difficulties and the lowest percentage with high impact score at age 18-19, but the differences were not statistically significant after adjustments. Weekly hours of physical activity at age 15-16 years was weakly associated with mental health at three-year follow-up in boys. Results encourage a search for further knowledge about physical activity as a possible protective factor in relation

  10. Interstellar chemistry

    Science.gov (United States)

    Klemperer, William

    2006-01-01

    In the past half century, radioastronomy has changed our perception and understanding of the universe. In this issue of PNAS, the molecular chemistry directly observed within the galaxy is discussed. For the most part, the description of the molecular transformations requires specific kinetic schemes rather than chemical thermodynamics. Ionization of the very abundant molecular hydrogen and atomic helium followed by their secondary reactions is discussed. The rich variety of organic species observed is a challenge for complete understanding. The role and nature of reactions involving grain surfaces as well as new spectroscopic observations of interstellar and circumstellar regions are topics presented in this special feature. PMID:16894148

  11. Statements of Agreement From the Targeted Evaluation and Active Management (TEAM) Approaches to Treating Concussion Meeting Held in Pittsburgh, October 15-16, 2015.

    Science.gov (United States)

    Collins, Michael W; Kontos, Anthony P; Okonkwo, David O; Almquist, Jon; Bailes, Julian; Barisa, Mark; Bazarian, Jeffrey; Bloom, O Josh; Brody, David L; Cantu, Robert; Cardenas, Javier; Clugston, Jay; Cohen, Randall; Echemendia, Ruben; Elbin, R J; Ellenbogen, Richard; Fonseca, Janna; Gioia, Gerard; Guskiewicz, Kevin; Heyer, Robert; Hotz, Gillian; Iverson, Grant L; Jordan, Barry; Manley, Geoffrey; Maroon, Joseph; McAllister, Thomas; McCrea, Michael; Mucha, Anne; Pieroth, Elizabeth; Podell, Kenneth; Pombo, Matthew; Shetty, Teena; Sills, Allen; Solomon, Gary; Thomas, Danny G; Valovich McLeod, Tamara C; Yates, Tony; Zafonte, Ross

    2016-12-01

    Conventional management for concussion involves prescribed rest and progressive return to activity. Recent evidence challenges this notion and suggests that active approaches may be effective for some patients. Previous concussion consensus statements provide limited guidance regarding active treatment. To describe the current landscape of treatment for concussion and to provide summary agreements related to treatment to assist clinicians in the treatment of concussion. On October 14 to 16, 2015, the Targeted Evaluation and Active Management (TEAM) Approaches to Treating Concussion meeting was convened in Pittsburgh, Pennsylvania. Thirty-seven concussion experts from neuropsychology, neurology, neurosurgery, sports medicine, physical medicine and rehabilitation, physical therapy, athletic training, and research and 12 individuals representing sport, military, and public health organizations attended the meeting. The 37 experts indicated their agreement on a series of statements using an audience response system clicker device. A total of 16 statements of agreement were supported covering (1) Summary of the Current Approach to Treating Concussion, (2) Heterogeneity and Evolving Clinical Profiles of Concussion, (3) TEAM Approach to Concussion Treatment: Specific Strategies, and (4) Future Directions: A Call to Research. Support (ie, response of agree or somewhat agree) for the statements ranged from to 97% to 100%. Concussions are characterized by diverse symptoms and impairments and evolving clinical profiles; recovery varies on the basis of modifying factors, injury severity, and treatments. Active and targeted treatments may enhance recovery after concussion. Research is needed on concussion clinical profiles, biomarkers, and the effectiveness and timing of treatments. ARS, audience response systemCDC, Centers for Disease Control and PreventionDoD, Department of DefensemTBI, mild traumatic brain injuryNCAA, National Collegiate Athletic AssociationNFL, National

  12. Combustion chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Brown, N.J. [Lawrence Berkeley Laboratory, CA (United States)

    1993-12-01

    This research is concerned with the development and use of sensitivity analysis tools to probe the response of dependent variables to model input variables. Sensitivity analysis is important at all levels of combustion modeling. This group`s research continues to be focused on elucidating the interrelationship between features in the underlying potential energy surface (obtained from ab initio quantum chemistry calculations) and their responses in the quantum dynamics, e.g., reactive transition probabilities, cross sections, and thermal rate coefficients. The goals of this research are: (i) to provide feedback information to quantum chemists in their potential surface refinement efforts, and (ii) to gain a better understanding of how various regions in the potential influence the dynamics. These investigations are carried out with the methodology of quantum functional sensitivity analysis (QFSA).

  13. Immobilization chemistries.

    Science.gov (United States)

    Todt, Sascha; Blohm, Dietmar H

    2009-01-01

    Among the parameters which influence the success of a microarray experiment, the attachment of the nucleic acid captures to the support surface plays a decisive role.This article attempts to review the main concepts and ideas of the multiple variants which exist in terms of the immobilization chemistries used in nucleic acid microarray technology. Starting from the attachment of unmodified nucleic acids to modified glass slides by adsorption, further strategies for the coupling of nucleic acid capture molecules to a variety of support materials are surveyed with a focus on the reactive groups involved in the respective process.After a brief introduction, an overview is given about microarray substrates with special emphasis on the approaches used for the activation of these - usually chemically inert - materials. In the next sections strategies for the "undefined" and "defined" immobilization of captures on the substrates are described. While the latter approach tries to accomplish the coupling via a defined reactive moiety of the molecule to be immobilized, the former mentioned techniques involve multiply occurring reactive groups in the capture.The article finishes with an example for microarray manufacture, the production of aminopropyltriethoxysilane (APTES) functionalized glass substrates to which PDITC homobifunctional linker molecules are coupled; on their part providing reactive functional groups for the covalent immobilization of pre-synthesized, amino-modified oligonucleotides.This survey does not seek to be comprehensive rather it tries to present and provide key examples for the basic techniques, and to enable orientation if more detailed studies are needed. This review should not be considered as a guide to how to use the different chemistries described, but instead as a presentation of various principles and approaches applied in the still evolving field of nucleic acid microarray technology.

  14. Public perception of chemistry

    OpenAIRE

    Stražar, Alenka

    2015-01-01

    The thesis deals with the perception of chemistry among the public, which reflects the stereotypes that people have about chemistry. It presents the existing classification of stereotypes about chemistry and their upgrade. An analysis of movies that reflect the existing perception of chemistry in the public is written. Literature on selected aspects of the application of chemistry in movies is collected and analyzed. A qualification of perception of chemistry in the movies is presented based ...

  15. 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...

  16. Science Update: Inorganic Chemistry.

    Science.gov (United States)

    Rawls, Rebecca

    1981-01-01

    Describes areas of inorganic chemistry which have changed dramatically in the past year or two, including photochemistry, electrochemistry, organometallic complexes, inorganic reaction theory, and solid state chemistry. (DS)

  17. Physics Conference TIM-15-16

    CERN Document Server

    2016-01-01

    The Conference is organized by the West University of Timisoara, Faculty of Physics. The scientific program of the conference will include invited lectures, oral and poster presentations, as well as discussions on various topics of present interest, such as, but not limited to condensed matter physics and applications, theoretical and computational physics, and applied physics.

  18. Physical chemistry II essentials

    CERN Document Server

    REA, The Editors of

    1992-01-01

    REA's Essentials provide quick and easy access to critical information in a variety of different fields, ranging from the most basic to the most advanced. As its name implies, these concise, comprehensive study guides summarize the essentials of the field covered. Essentials are helpful when preparing for exams, doing homework and will remain a lasting reference source for students, teachers, and professionals. Physical Chemistry II includes reaction mechanisms, theoretical approaches to chemical kinetics, gravitational work, electrical and magnetic work, surface work, kinetic theory, collisional and transport properties of gases, statistical mechanics, matter and waves, quantum mechanics, and rotations and vibrations of atoms and molecules.

  19. Analytical chemistry in space

    CERN Document Server

    Wainerdi, Richard E

    1970-01-01

    Analytical Chemistry in Space presents an analysis of the chemical constitution of space, particularly the particles in the solar wind, of the planetary atmospheres, and the surfaces of the moon and planets. Topics range from space engineering considerations to solar system atmospheres and recovered extraterrestrial materials. Mass spectroscopy in space exploration is also discussed, along with lunar and planetary surface analysis using neutron inelastic scattering. This book is comprised of seven chapters and opens with a discussion on the possibilities for exploration of the solar system by

  20. Insect Pheromone-Alfa Chemistry.pptx

    OpenAIRE

    Keller, Tylor

    2017-01-01

    Pheromones are substances produced as messengers that affect the behavior of other insects, animals and members of the same species. Alfa Chemistry offers a wide range of different insect pheromones that respond to control pests effectively and respectfully with the environment. Visit http://www.alfa-chemistry.com/products/insect-pheromone-5.htm for more.

  1. Chemistry in Our Life

    Indian Academy of Sciences (India)

    IAS Admin

    toothpaste, soaps and cosmetics, (7) plastics and polymers, (8) chemistry in health and disease, (9) chemistry of building, (10) fire chemistry and (11) chemistry of electricity. To write on these topics at a popular level for lay persons, without bringing in chemical for- mulas, structures or equations, is extremely difficult.

  2. Spectroscopic and microbiological characterization of labdane diterpene 15,16-epoxy-4-hydroxy-labda-13(16),14-dien-3,12-dione isolated from the stems of Croton jacobinensis

    Science.gov (United States)

    Bernardino, A. C. S. S.; Teixeira, A. M. R.; de Menezes, J. E. S. A.; Pinto, C. C. C.; Santos, H. S.; Freire, P. T. C.; Coutinho, H. D. M.; Sena Junior, D. M.; Bandeira, P. N.; Braz-Filho, R.

    2017-11-01

    In the present study, the natural product named 15,16-epoxy-4-hydroxy-labda-13(16),14-dien-3,12-dione (C20H28O4), a labdane-type diterpene was isolated from the stems of Croton jacobinensis for the first time. This new compound was characterized by infrared and Raman spectroscopy combined with Density Functional Theory calculation. Additionally, the antimicrobial and modulatory antibiotic activities of the compound towards Escherichia coli and Pseudomonas aeruginosa strains were assessed. The labdane diterpene demonstrated a modulatory effect when combined with the antibiotics assayed against both bacteria. A synergistic effect against Escherichia coli can be observed when the compound is associated with gentamicin, reducing the concentration of this antibiotic that is required to inhibit bacterial growth. Other synergistic effects can be observed with gentamicin and cephalothin antibiotics against P. aeruginosa.

  3. 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...

  4. Radiation chemistry research using PULAF

    Energy Technology Data Exchange (ETDEWEB)

    Gaikwad, Parimal [National Centre for Free Radical Research, Department of Chemistry, University of Pune, Pune 411 007 (India); Priyadarsini, K.I. [Radiation and Photochemistry Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400 085 (India); Rao, B.S.M. [National Centre for Free Radical Research, Department of Chemistry, University of Pune, Pune 411 007 (India)], E-mail: bsmr@chem.unipune.ernet.in

    2008-10-15

    The details of the recently installed 7 MeV Pune University LINAC Facility (PULAF) coupled with the optical absorption technique for pulse radiolysis studies at the National Centre for Free Radical Research, Department of Chemistry, University of Pune, Pune, India are described. The facility has a selection of electron pulse widths in the range 10 ns-3 {mu}s with corresponding doses of about 5-144 Gy per pulse. The operation of the machine and the detection system are fully automated. Several researchers from various Indian universities and national laboratories use the PULAF and some of the projects that are currently undertaken by our group and others include the radiation chemistry of indole and chalcone derivatives, herbal antioxidants, structure-reactivity studies in cinnamates, redox chemistry of inorganic metal complexes, studies on oxidation of pyrimidine analogues and aromatic sulphur compounds. Some of them are briefly discussed here.

  5. Atmospheric Chemistry and Air Pollution

    Directory of Open Access Journals (Sweden)

    Jeffrey S. Gaffney

    2003-01-01

    Full Text Available Atmospheric chemistry is an important discipline for understanding air pollution and its impacts. This mini-review gives a brief history of air pollution and presents an overview of some of the basic photochemistry involved in the production of ozone and other oxidants in the atmosphere. Urban air quality issues are reviewed with a specific focus on ozone and other oxidants, primary and secondary aerosols, alternative fuels, and the potential for chlorine releases to amplify oxidant chemistry in industrial areas. Regional air pollution issues such as acid rain, long-range transport of aerosols and visibility loss, and the connections of aerosols to ozone and peroxyacetyl nitrate chemistry are examined. Finally, the potential impacts of air pollutants on the global-scale radiative balances of gases and aerosols are discussed briefly.

  6. 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.

  7. 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.

  8. Organometallic Neptunium Chemistry.

    Science.gov (United States)

    Arnold, Polly L; Dutkiewicz, Michał S; Walter, Olaf

    2017-09-13

    Fifty years have passed since the foundation of organometallic neptunium chemistry, and yet only a handful of complexes have been reported, and even fewer have been fully characterized. Yet, increasingly, combined synthetic/spectroscopic/computational studies are demonstrating how covalently bonding, soft, carbocyclic organometallic ligands provide an excellent platform for advancing the fundamental understanding of the differences in orbital contributions and covalency in f-block metal-ligand bonding. Understanding the subtleties is the key to the safe handling and separations of the highly radioactive nuclei. This review describes the complexes that have been synthesized to date and presents a critical assessment of the successes and difficulties in their analysis and the bonding information they have provided. Because of increasing recent efforts to start new Np-capable air-sensitive inorganic chemistry laboratories, the importance of radioactivity, the basics of Np decay and its ramifications (including the radiochemical synthesis of one organometallic compound), and the available anhydrous starting materials are also surveyed. The review also highlights a range of instances in which important differences in the chemical behavior between Np and its closest neighbors, uranium and plutonium, are found.

  9. Coordination Chemistry of Life Processes: Bioinorganic Chemistry

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 4; Issue 9. Coordination Chemistry of Life Processes: Bioinorganic Chemistry. R N Mukherjee. General Article Volume 4 Issue 9 September 1999 pp 53-62. Fulltext. Click here to view fulltext PDF. Permanent link:

  10. Environmental chemistry: Volume A

    Energy Technology Data Exchange (ETDEWEB)

    Yen, T.F.

    1999-08-01

    This is an extensive introduction to environmental chemistry for engineering and chemical professionals. The contents of Volume A include a brief review of basic chemistry prior to coverage of litho, atmo, hydro, pedo, and biospheres.

  11. A dictionary of chemistry

    National Research Council Canada - National Science Library

    Daintith, John

    2008-01-01

    "Fully revised and updated, the sixth edition of this popular dictionary covers all aspects of chemistry from physical chemistry to biochemisty, and boasts broader coverage in forensics, metallurgy, and geology...

  12. Organometallic Chemistry of Molybdenum.

    Science.gov (United States)

    Lucas, C. Robert; Walsh, Kelly A.

    1987-01-01

    Suggests ways to avoid some of the problems students have learning the principles of organometallic chemistry. Provides a description of an experiment used in a third-year college chemistry laboratory on molybdenum. (TW)

  13. 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...

  14. Chemistry is Evergreen

    Indian Academy of Sciences (India)

    Srimath

    RESONANCE ⎜ March 2009. GENERAL ⎜ ARTICLE. Keywords. Green fluorescent protein,. FRET. Chemistry is Evergreen. 2008 Nobel Prize in Chemistry. Swagata Dasgupta. Swagata Dasgupta is an. Associate Professor in the. Department of Chemistry at IIT Kharagpur. Her research interests revolve around proteins and ...

  15. Green Chemistry and Education.

    Science.gov (United States)

    Hjeresen, Dennis L.; Schutt, David L.; Boese, Janet M.

    2000-01-01

    Many students today are profoundly interested in the sustainability of their world. Introduces Green Chemistry and its principles with teaching materials. Green Chemistry is the use of chemistry for pollution prevention and the design of chemical products and processes that are environmentally benign. (ASK)

  16. 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 ...

  17. Structure and chemistry of model catalysts in ultrahigh vacuum

    Science.gov (United States)

    Walker, Joshua D.

    molecular geometry on electron transport using a range of surface-sensitive techniques. Sulfur-containing molecules, in particular those with sulfur-sulfur linkages, are used as lubricant additives for ferrous surfaces [1-14] so that dialkyl disulfides have been used as simple model compounds to explore the surface and tribological chemistry on iron [15,16] where they react at the high temperatures attained at the interface during rubbing to deposit a ferrous sulfide film. However, the tribological chemistry can depend critically on the nature of the substrate so that a good lubricant additive for one type of surface may not be applicable to another. In particular, the lubrication of sliding copper-copper interfaces in electrical motors [17-20] provides a particular challenge. To study this system surface sensitive techniques Low energy electron diffraction (LEED) and TPD surface analysis was employed. LEED experiments suggest that tribological experiments can be conducted on copper foils rather than copper single crystals and produce comparable results. The ability to produce ideal model catalysts is very important in the Surface science field. To enhance catalytic performance of these catalysts, various strategies can be used in the preparation process. One approach in this quest is to produce an alloy surface that increases the activity of the surface. The process of developing and understanding the chemistry of AuPd alloys was probed in detail using TPD, LEED and Density Functional Theory (DFT).

  18. 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.

  19. 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...

  20. Major Range and Test Facility Base Summary of Capabilities.

    Science.gov (United States)

    1983-06-01

    V:ISHAM LINDER Director Defense Test and Evaluation *1 DoD 3200.11-D MAJOR RANGE AND TEST FACILITY BASE SUMMARY OF CAPABILITIES TABLE OF CONTENTS White...suitable for zero g testing and rocket plume signature studies. TYPICAL PROJECTS SUPPORTED B-i and F-15/16 Air-Launched Cruise Missile Global Position...rocket plumes , trucks, and other aerospace and ground-based objects. The RATSCAT facility is isolated physically and electromagnetically by its

  1. Hereditary nonpolyposis colon cancer: Analysis of linkage to 2p 15-16 places the COCA1 locus telomeric to D2S123 and reveals genetic heterogeneity in seven Canadian families

    Energy Technology Data Exchange (ETDEWEB)

    Green, R.C.; Young, T.L. (Memorial Univ. of Newfoundland, St. John' s (Canada)); Narod, S.A.; Tonin, P.; Ginsburg, O.; Miller, S. (Montreal General Hospital, Montreal (Canada) Royal Victoria Hospital, Montreal (Canada)); Morasse, J. (Hopital St-Francois d' Assise, Quebec City (Canada)); Cox, J.; Fitzgerald, G.W.N. (Grenfell Regional Health Services, St. Anthony, Newfoundland (Canada)); Jothy, S. (Royal Victoria Hospital, Montreal (Canada)) (and others)

    1994-06-01

    Hereditary nonpolyposis colon cancer (HNPCC) is an autosomal dominant trait responsible for approximately 6% of colorectal cancers. Linkage of the HNPCC trait to the D2S123 locus on 2p 15-16 has previously been reported in two families. This HNPCC locus is now designated [open quotes]COCA1[close quotes]. The authors have tested seven Canadian HNPCC families, who have a variety of clinical presentations, for linkage to a panel of microsatellite polymorphisms in the vicinity of D2S123. One family was clearly linked to the COCA1 locus (LOD = 4.21), and a second family is likely to be linked (LOD = 0.92). In three families linkage was excluded. In the remaining two families the data were inconclusive. In the linked family, individuals with cancer of the endometrium or ureter share a common haplotype with 12 family members with colorectal cancer. This supports the suspected association between these extracolonic neoplasms and the HNPCC syndrome. In addition, five of the six individuals with adenomatous polyps (but no colorectal cancer) have the same haplotype as the affected individuals, while the sixth carries a recombination. One individual with colorectal cancer carries a recombination that places the COCA1 locus telomeric to D2S123. This study localizes the COCA1 gene to an 8-cM region that is consistent with the location of the hMSH2 gene. The authors also confirm that families presently classified as HNPCC are genetically heterogeneous. 36 refs., 4 figs., 2 tabs.

  2. Journal of Business Chemistry

    OpenAIRE

    2013-01-01

    The Journal of Business Chemistry examines issues associated with leadership and management for chemists and managers working in chemical research or industry. This journal is devoted to improving and developing the field of Business Chemistry. The Journal of Business Chemistry publishes peer-reviewed papers (including case studies) and essays. Areas for possible publication in include: leadership issues in the chemical and biochemical industry, such as teamwork, team building, mentoring, coa...

  3. Orbital interactions in chemistry

    CERN Document Server

    Albright, Thomas A; Whangbo, Myung-Hwan

    2013-01-01

    Explains the underlying structure that unites all disciplines in chemistry Now in its second edition, this book explores organic, organometallic, inorganic, solid state, and materials chemistry, demonstrating how common molecular orbital situations arise throughout the whole chemical spectrum. The authors explore the relationships that enable readers to grasp the theory that underlies and connects traditional fields of study within chemistry, thereby providing a conceptual framework with which to think about chemical structure and reactivity problems. Orbital Interactions

  4. USSR Report, Chemistry

    National Research Council Canada - National Science Library

    1986-01-01

    This USSR Report on Chemistry contains articles on Aerosols, Adsorption, Biochemistry, Catalysis, Chemical Industry, Coal Gasification, Electrochemistry, Explosives and Explosions, Fertilizers, Food...

  5. 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

  6. Canopy Chemistry (OTTER)

    Data.gov (United States)

    National Aeronautics and Space Administration — Canopy characteristics: leaf chemistry, specific leaf area, LAI, PAR, IPAR, NPP, standing biomass--see also: Meteorology (OTTER) for associated meteorological...

  7. Solution phase combinatorial chemistry.

    Science.gov (United States)

    Merritt, A T

    1998-06-01

    Combinatorial chemistry and parallel array synthesis techniques are now used extensively in the drug discovery process. Although published literature has been dominated by solid phase chemistry approaches, the use of solution phase techniques has also been widely explored. This review considers the advantages and disadvantages of choosing solution phase approaches in the various stages of drug discovery and optimisation, and assesses the practical issues related to these approaches. The uses of standard solution chemistry, the related liquid phase approach, and of supported materials to enhance solution phase chemistry are all illustrated by a comprehensive review of the published literature over the past three years.

  8. Elements of environmental chemistry

    National Research Council Canada - National Science Library

    Hites, R. A; Raff, Jonathan D

    2012-01-01

    ... more. Extensively revised, updated, and expanded, this second edition includes new chapters on atmospheric chemistry, climate change, and polychlorinated biphenyls and dioxins, and brominated flame retardants...

  9. Computational Chemistry for Kids

    National Research Council Canada - National Science Library

    Naef, Olivier

    2000-01-01

    This article aims to show that computational chemistry is not exclusively restricted to molecular energy and structure calculations but also includes chemical process control and reaction simulation...

  10. Diversity in Medicinal Chemistry.

    Science.gov (United States)

    Peralta, David

    2018-01-08

    The wide world of medicinal chemistry: We look back at our activities in 2017, particularly the expansion of the journal's scope to nanomedicine and why we need a more inclusive medicinal chemistry journal. Additionally, we look at upcoming special issues and developments for ChemPubSoc Europe in 2018. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Chemistry in Microfluidic Channels

    Science.gov (United States)

    Chia, Matthew C.; Sweeney, Christina M.; Odom, Teri W.

    2011-01-01

    General chemistry introduces principles such as acid-base chemistry, mixing, and precipitation that are usually demonstrated in bulk solutions. In this laboratory experiment, we describe how chemical reactions can be performed in a microfluidic channel to show advanced concepts such as laminar fluid flow and controlled precipitation. Three sets of…

  12. Exercises in Computational Chemistry

    DEFF Research Database (Denmark)

    Spanget-Larsen, Jens

    2016-01-01

    A selection of HyperChem© PC-exercises in computational chemistry. Answers to most questions are appended (Roskilde University 2014-16).......A selection of HyperChem© PC-exercises in computational chemistry. Answers to most questions are appended (Roskilde University 2014-16)....

  13. The Breath of Chemistry

    DEFF Research Database (Denmark)

    Josephsen, Jens

    The present preliminary text is a short thematic presentation in biological inorganic chemistry meant to illustrate general and inorganic (especially coordination) chemistry in biochemistry. The emphasis is on molecular models to explain features of the complicated mechanisms essential to breathing...

  14. Movies in Chemistry Education

    Science.gov (United States)

    Pekdag, Bulent; Le Marechal, Jean-Francois

    2010-01-01

    This article reviews numerous studies on chemistry movies. Movies, or moving pictures, are important elements of multimedia and signify a privileged or motivating means of presenting knowledge. Studies on chemistry movies show that the first movie productions in this field were devoted to university lectures or documentaries. Shorter movies were…

  15. Chemistry of americium

    Energy Technology Data Exchange (ETDEWEB)

    Schulz, W.W.

    1976-01-01

    Essential features of the descriptive chemistry of americium are reviewed. Chapter titles are: discovery, atomic and nuclear properties, collateral reading, production and uses, chemistry in aqueous solution, metal, alloys, and compounds, and, recovery, separation, purification. Author and subject indexes are included. (JCB)

  16. Chemistry is Evergreen

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 14; Issue 3. Chemistry is Everygreen - 2008 Nobel Prize in Chemistry. Swagata Dasgupta. General Article Volume 14 Issue 3 March 2009 pp 248-258. Fulltext. Click here to view fulltext PDF. Permanent link:

  17. 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.

  18. Biosynthetic inorganic chemistry.

    Science.gov (United States)

    Lu, Yi

    2006-08-25

    Inorganic chemistry and biology can benefit greatly from each other. Although synthetic and physical inorganic chemistry have been greatly successful in clarifying the role of metal ions in biological systems, the time may now be right to utilize biological systems to advance coordination chemistry. One such example is the use of small, stable, easy-to-make, and well-characterized proteins as ligands to synthesize novel inorganic compounds. This biosynthetic inorganic chemistry is possible thanks to a number of developments in biology. This review summarizes the progress in the synthesis of close models of complex metalloproteins, followed by a description of recent advances in using the approach for making novel compounds that are unprecedented in either inorganic chemistry or biology. The focus is mainly on synthetic "tricks" learned from biology, as well as novel structures and insights obtained. The advantages and disadvantages of this biosynthetic approach are discussed.

  19. Marine fragrance chemistry.

    Science.gov (United States)

    Hügel, Helmut M; Drevermann, Britta; Lingham, Anthony R; Marriott, Philip J

    2008-06-01

    The main marine message in perfumery is projected by Calone 1951 (7-methyl-2H-1,5-benzodioxepin-3(4H)-one). Kraft (Givaudan) and Gaudin (Firmenich) further maximized the marine fragrance molecular membership by extending the carbon chain of the 7-Me group. Our research targeted the polar group of the benzodioxepinone parent compound to investigate how this region of molecular makeup resonates with the dominant marine fragrance of the Calone 1951 structure. The olfactory evaluation of analogues prepared by chemical modification or removal of the CO group resulted in the introduction of aldehydic, sweet and floral-fruity notes with a diluted/diminished potency of the marine odor. To further analyze the olfactory properties of benzodioxepinones containing a diverse range of aromatic ring substituents, a novel synthesis route was developed. We found that a 7-alkyl group in Calone 1951 was essential for the maintenance of the significant marine odor characteristic, and our studies support the concept that the odorant structure occupying the hydrophobic binding pocket adjacent to the aromatic ring-binding site of the olfactory receptor is pivotal in the design and discovery of more potent and characteristic marine fragrances. How the structure of benzodioxepinones connects to marine sea-breeze fragrances is our continuing challenging research focus at the chemistry-biology interface.

  20. ENVIRONMENTAL ANALYTICAL CHEMISTRY OF ...

    Science.gov (United States)

    Within the scope of a number of emerging contaminant issues in environmental analysis, one area that has received a great deal of public interest has been the assessment of the role of pharmaceuticals and personal care products (PPCPs) as stressors and agents of change in ecosystems as well as their role in unplanned human exposure. The relationship between personal actions and the occurrence of PPCPs in the environment is clear-cut and comprehensible to the public. In this overview, we attempt to examine the separations aspect of the analytical approach to the vast array of potential analytes among this class of compounds. We also highlight the relationship between these compounds and endocrine disrupting compounds (EDCs) and between PPCPs and EDCs and the more traditional environmental analytes such as the persistent organic pollutants (POPs). Although the spectrum of chemical behavior extends from hydrophobic to hydrophilic, the current focus has shifted to moderately and highly polar analytes. Thus, emphasis on HPLC and LC/MS has grown and MS/MS has become a detection technique of choice with either electrospray ionization or atmospheric pressure chemical ionization. This contrasts markedly with the bench mark approach of capillary GC, GC/MS and electron ionization in traditional environmental analysis. The expansion of the analyte list has fostered new vigor in the development of environmental analytical chemistry, modernized the range of tools appli

  1. Korean Kimchi Chemistry: A Multicultural Chemistry Connection

    Science.gov (United States)

    Murfin, Brian

    2009-01-01

    Connecting science with different cultures is one way to interest students in science, to relate science to their lives, and at the same time to broaden their horizons in a variety of ways. In the lesson described here, students make kimchi, a delicious and popular Korean dish that can be used to explore many important chemistry concepts,…

  2. Chemistry of fast electrons

    Science.gov (United States)

    Maximoff, Sergey N.; Head-Gordon, Martin P.

    2009-01-01

    A chemicurrent is a flux of fast (kinetic energy ≳ 0.5−1.3 eV) metal electrons caused by moderately exothermic (1−3 eV) chemical reactions over high work function (4−6 eV) metal surfaces. In this report, the relation between chemicurrent and surface chemistry is elucidated with a combination of top-down phenomenology and bottom-up atomic-scale modeling. Examination of catalytic CO oxidation, an example which exhibits a chemicurrent, reveals 3 constituents of this relation: The localization of some conduction electrons to the surface via a reduction reaction, 0.5 O2 + δe− → Oδ− (Red); the delocalization of some surface electrons into a conduction band in an oxidation reaction, Oδ− + CO → CO2δ− → CO2 + δe− (Ox); and relaxation without charge transfer (Rel). Juxtaposition of Red, Ox, and Rel produces a daunting variety of metal electronic excitations, but only those that originate from CO2 reactive desorption are long-range and fast enough to dominate the chemicurrent. The chemicurrent yield depends on the universality class of the desorption process and the distribution of the desorption thresholds. This analysis implies a power-law relation with exponent 2.66 between the chemicurrent and the heat of adsorption, which is consistent with experimental findings for a range of systems. This picture also applies to other oxidation-reduction reactions over high work function metal surfaces. PMID:19561296

  3. 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...

  4. Mathematics for physical chemistry

    CERN Document Server

    Mortimer, Robert G

    2013-01-01

    Mathematics for Physical Chemistry is the ideal supplementary text for practicing chemists and students who want to sharpen their mathematics skills while enrolled in general through physical chemistry courses. This book specifically emphasizes the use of mathematics in the context of physical chemistry, as opposed to being simply a mathematics text. This 4e includes new exercises in each chapter that provide practice in a technique immediately after discussion or example and encourage self-study. The early chapters are constructed around a sequence of mathematical topics, wit

  5. Gas phase ion chemistry

    CERN Document Server

    Bowers, Michael T

    1979-01-01

    Gas Phase Ion Chemistry, Volume 1 covers papers on the advances of gas phase ion chemistry. The book discusses the advances in flow tubes and the measurement of ion-molecule rate coefficients and product distributions; the ion chemistry of the earth's atmosphere; and the classical ion-molecule collision theory. The text also describes statistical methods in reaction dynamics; the state selection by photoion-photoelectron coincidence; and the effects of temperature and pressure in the kinetics of ion-molecule reactions. The energy distribution in the unimolecular decomposition of ions, as well

  6. Spatially Resolved Artificial Chemistry

    DEFF Research Database (Denmark)

    Fellermann, Harold

    2009-01-01

    Although spatial structures can play a crucial role in chemical systems and can drastically alter the outcome of reactions, the traditional framework of artificial chemistry is a well-stirred tank reactor with no spatial representation in mind. Advanced method development in physical chemistry has...... made a class of models accessible to the realms of artificial chemistry that represent reacting molecules in a coarse-grained fashion in continuous space. This chapter introduces the mathematical models of Brownian dynamics (BD) and dissipative particle dynamics (DPD) for molecular motion and reaction...

  7. Experiments in physical chemistry

    CERN Document Server

    Wilson, J M; Denaro, A R

    1968-01-01

    Experiments in Physical Chemistry, Second Edition provides a compilation of experiments concerning physical chemistry. This book illustrates the link between the theory and practice of physical chemistry. Organized into three parts, this edition begins with an overview of those experiments that generally have a simple theoretical background. Part II contains experiments that are associated with more advanced theory or more developed techniques, or which require a greater degree of experimental skill. Part III consists of experiments that are in the nature of investigations wherein these invest

  8. Nuclear Forensics and Radiochemistry: Chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Rundberg, Robert S. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-11-17

    The chemical behavior of radioactive elements can differ from conventional wisdom because the number of atoms can be unusually small. Kinetic effects and unusual oxidation states are phenomena that make radiochemistry different from conventional analytic chemistry. The procedures developed at Los Alamos are designed to minimize these effects and provide reproducible results over a wide range of sample types. The analysis of nuclear debris has the additional complication of chemical fractionation and the incorporation of environmental contaminants. These are dealt with through the use of three component isotope ratios and the use of appropriate end members.

  9. Surface Chemistry in Nanoscale Materials

    Directory of Open Access Journals (Sweden)

    Alex V. Hamza

    2009-12-01

    Full Text Available Although surfaces or, more precisely, the surface atomic and electronic structure, determine the way materials interact with their environment, the influence of surface chemistry on the bulk of the material is generally considered to be small. However, in the case of high surface area materials such as nanoporous solids, surface properties can start to dominate the overall material behavior. This allows one to create new materials with physical and chemical properties that are no longer determined by the bulk material, but by their nanoscale architectures. Here, we discuss several examples, ranging from nanoporous gold to surface engineered carbon aerogels that demonstrate the tuneability of nanoporous solids for sustainable energy applications.

  10. Surface Chemistry in Nanoscale Materials

    Science.gov (United States)

    Biener, Jürgen; Wittstock, Arne; Baumann, Theodore F.; Weissmüller, Jörg; Bäumer, Marcus; Hamza, Alex V.

    2009-01-01

    Although surfaces or, more precisely, the surface atomic and electronic structure, determine the way materials interact with their environment, the influence of surface chemistry on the bulk of the material is generally considered to be small. However, in the case of high surface area materials such as nanoporous solids, surface properties can start to dominate the overall material behavior. This allows one to create new materials with physical and chemical properties that are no longer determined by the bulk material, but by their nanoscale architectures. Here, we discuss several examples, ranging from nanoporous gold to surface engineered carbon aerogels that demonstrate the tuneability of nanoporous solids for sustainable energy applications.

  11. Bioinorganic Chemistry of the Alkali Metal Ions.

    Science.gov (United States)

    Kim, Youngsam; Nguyen, Thuy-Tien T; Churchill, David G

    2016-01-01

    The common Group 1 alkali metals are indeed ubiquitous on earth, in the oceans and in biological systems. In this introductory chapter, concepts involving aqueous chemistry and aspects of general coordination chemistry and oxygen atom donor chemistry are introduced. Also, there are nuclear isotopes of importance. A general discussion of Group 1 begins from the prevalence of the ions, and from a comparison of their ionic radii and ionization energies. While oxygen and water molecule binding have the most relevance to biology and in forming a detailed understanding between the elements, there is a wide range of basic chemistry that is potentially important, especially with respect to biological chelation and synthetic multi-dentate ligand design. The elements are widely distributed in life forms, in the terrestrial environment and in the oceans. The details about the workings in animal, as well as plant life are presented in this volume. Important biometallic aspects of human health and medicine are introduced as well. Seeing as the elements are widely present in biology, various particular endogenous molecules and enzymatic systems can be studied. Sodium and potassium are by far the most important and central elements for consideration. Aspects of lithium, rubidium, cesium and francium chemistry are also included; they help in making important comparisons related to the coordination chemistry of Na(+) and K(+). Physical methods are also introduced.

  12. Chemistry with a Peel.

    Science.gov (United States)

    Borer, Londa; Larsen, Eric

    1997-01-01

    Presents experiments that introduce natural product chemistry into high school classrooms. In the laboratory activities, students isolate and analyze the oil in orange peels. Students also perform a steam distillation and learn about terpenes. (DDR)

  13. Indicators: Soil Chemistry

    Science.gov (United States)

    The chemical makeup of the soil can provide information on wetland condition, wetland water quality and services being provided by the wetland ecosystem. Analyzing soil chemistry reveals if the soil is contaminated with a toxic chemical or heavy metal.

  14. Microfluidics in inorganic chemistry.

    Science.gov (United States)

    Abou-Hassan, Ali; Sandre, Olivier; Cabuil, Valérie

    2010-08-23

    The application of microfluidics in chemistry has gained significant importance in the recent years. Miniaturized chemistry platforms provide controlled fluid transport, rapid chemical reactions, and cost-saving advantages over conventional reactors. The advantages of microfluidics have been clearly established in the field of analytical and bioanalytical sciences and in the field of organic synthesis. It is less true in the field of inorganic chemistry and materials science; however in inorganic chemistry it has mostly been used for the separation and selective extraction of metal ions. Microfluidics has been used in materials science mainly for the improvement of nanoparticle synthesis, namely metal, metal oxide, and semiconductor nanoparticles. Microfluidic devices can also be used for the formulation of more advanced and sophisticated inorganic materials or hybrids.

  15. Supplemental instruction in chemistry

    Science.gov (United States)

    Lundeberg, Mary A.

    This study was designed to measure some effects of supplemental instruction in chemistry. Supplemental instruction is a peer-led cooperative learning program that encourages students to develop conceptual understanding by articulating both understandings and misconceptions in a think-aloud fashion. Supplemental instruction was offered three hours weekly outside of class and lab time for students in four classes of General Organic and Biological Chemistry. Over a two-year period 108 students volunteered to participate in this program; 45 students did not participate. As measured by final grades in chemistry and responses to a questionnaire, supplemental instruction was effective in increasing students' achievement in chemistry. Further research is needed to determine the in-depth effects of supplemental instruction on students' learning, problem solving, and self-esteem.

  16. Electrostatics in Chemistry

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 4; Issue 7. Electrostatics in Chemistry - Molecular Electrostatic Potential: Visualization and Topography. Shridhar R Gadre Pravin K Bhadane. Series Article Volume 4 Issue 7 July 1999 pp 14-23 ...

  17. Mapping the Teaching of History of Chemistry in Europe

    Science.gov (United States)

    Suay-Matallana, Ignacio; Sanchez, Jose´ Ramon Bertomeu

    2017-01-01

    Recent developments in the field of history of chemistry have introduced new topics, challenges, and connections to a broad range of scientific, political, cultural, economic, and environmental issues. New audiences for the history of chemistry have emerged along with new topics, protagonists, spaces, and historical narratives. This paper…

  18. Making Students Eat Their Greens: Information Skills for Chemistry Students

    Science.gov (United States)

    George, Sarah; Munshi, Tasnim

    2016-01-01

    Employers are increasingly requiring a range of "soft" skills from chemistry graduates, including the ability to search for and critically evaluate information. This paper discusses the issues around encouraging chemistry students to engage with information skills and suggests curricular changes which may help to "drip-feed"…

  19. Making Students Eat Their Greens: Information Skills for Chemistry Students

    Directory of Open Access Journals (Sweden)

    Sarah George

    2016-12-01

    Full Text Available Employers are increasingly requiring a range of "soft" skills from chemistry graduates, including the ability to search for and critically evaluate information. This paper discusses the issues around encouraging chemistry students to engage with information skills and suggests curricular changes which may help to "drip-feed" information skills into degree programs.

  20. Applications of supramolecular chemistry

    CERN Document Server

    Schneider, Hans-Jörg

    2012-01-01

    ""The time is ripe for the present volume, which gathers thorough presentations of the numerous actually realized or potentially accessible applications of supramolecular chemistry by a number of the leading figures in the field. The variety of topics covered is witness to the diversity of the approaches and the areas of implementation…a broad and timely panorama of the field assembling an eminent roster of contributors.""-Jean-Marie Lehn, 1987 Noble Prize Winner in Chemistry

  1. Fundamentals of quantum chemistry

    CERN Document Server

    House, J E

    2004-01-01

    An introduction to the principles of quantum mechanics needed in physical chemistry. Mathematical tools are presented and developed as needed and only basic calculus, chemistry, and physics is assumed. Applications include atomic and molecular structure, spectroscopy, alpha decay, tunneling, and superconductivity. New edition includes sections on perturbation theory, orbital symmetry of diatomic molecules, the Huckel MO method and Woodward/Hoffman rules as well as a new chapter on SCF and Hartree-Fock methods. * This revised text clearly presents basic q

  2. Gas phase ion chemistry

    CERN Document Server

    Bowers, Michael T

    1979-01-01

    Gas Phase Ion Chemistry, Volume 2 covers the advances in gas phase ion chemistry. The book discusses the stabilities of positive ions from equilibrium gas-phase basicity measurements; the experimental methods used to determine molecular electron affinities, specifically photoelectron spectroscopy, photodetachment spectroscopy, charge transfer, and collisional ionization; and the gas-phase acidity scale. The text also describes the basis of the technique of chemical ionization mass spectrometry; the energetics and mechanisms of unimolecular reactions of positive ions; and the photodissociation

  3. Tropical Soil Chemistry

    DEFF Research Database (Denmark)

    Borggaard, Ole K.

    and environmental protection. Tropical Soil Chemistry by Ole K. Borggaard provides an overview of the composition, occurrence, properties, processes, formation, and environmental vulnerability of various tropical soil types (using American Soil Taxonomy for classification). The processes and the external factors...... soil chemical issues are also presented to assess when, why, and how tropical soils differ from soils in other regions. This knowledge can help agricultural specialists in the tropics establish sustainable crop production. Readers are assumed to be familiar with basic chemistry, physics...

  4. Impact of surface chemistry

    Science.gov (United States)

    Somorjai, Gabor A.; Li, Yimin

    2011-01-01

    The applications of molecular surface chemistry in heterogeneous catalyst technology, semiconductor-based technology, medical technology, anticorrosion and lubricant technology, and nanotechnology are highlighted in this perspective. The evolution of surface chemistry at the molecular level is reviewed, and the key roles of surface instrumentation developments for in situ studies of the gas–solid, liquid–solid, and solid–solid interfaces under reaction conditions are emphasized. PMID:20880833

  5. Secondary Chemistry School Teachers Working in Tertiary Education Chemistry Departments; Critical Reflections on the Positives and Negatives

    Science.gov (United States)

    Glover, S. R.; Harrison, T. G.; Shallcross, D. E.

    2016-01-01

    Several UK University Chemistry Departments have former secondary school chemistry teachers employed as School Teacher Fellows (STF) who are heavily involved in outreach work and a range of teaching responsibilities. This study looks at the outreach role from the point of view of several of the STFs; the benefits, and the barriers and how this…

  6. Measuring Student Performance in General Organic Chemistry

    Science.gov (United States)

    Austin, Ara C.; Ben-Daat, Hagit; Zhu, Mary; Atkinson, Robert; Barrows, Nathan; Gould, Ian R.

    2015-01-01

    Student performance in general organic chemistry courses is determined by a wide range of factors including cognitive ability, motivation and cultural capital. Previous work on cognitive factors has tended to focus on specific areas rather than exploring performance across all problem types and cognitive skills. In this study, we have categorized…

  7. Evolution of dynamic combinatorial chemistry.

    Science.gov (United States)

    Cougnon, Fabien B L; Sanders, Jeremy K M

    2012-12-18

    Since its inception in the mid-1990s, dynamic combinatorial chemistry (DCC), the chemistry of complex systems under thermodynamic control, has proved valuable in identifying unexpected molecules with remarkable binding properties and in providing effective synthetic routes to complex species. Essentially, in this approach, one designs the experiment rather than the molecule. DCC has also provided us with insights into how some chemical systems respond to external stimuli. Using examples from the work of our laboratory and others, this Account shows how the concept of DCC, inspired by the evolution of living systems, has found an increasing range of applications in diverse areas and has evolved conceptually and experimentally. A dynamic combinatorial library (DCL) is a thermodynamically controlled mixture of interconverting species that can respond to various stimuli. The Cambridge version of dynamic combinatorial chemistry was initially inspired by the mammalian immune system and was conceived as a way to create and identify new unpredictable receptors. For example, an added template can select and stabilize a strongly binding member of the library which is then amplified at the expense of the unsuccessful library members, minimizing the free energy of the system. But researchers have exploited DCC in a variety of other ways: over the past two decades, this technique has contributed to the evolution of chemistry and to applications in the diverse fields of catalysis, fragrance release, and responsive materials. Among these applications, researchers have built intricate and well-defined architectures such as catenanes or hydrogen-bonded nanotubes, using the ability of complex chemical systems to reach a high level of organization. In addition, DCC has proved a powerful tool for the study of complex molecular networks and systems. The use of DCC is improving our understanding of chemical and biological systems. The study of folding or self-replicating macrocycles in

  8. Chemistry beyond positivism.

    Science.gov (United States)

    Brandt, Werner W

    2003-05-01

    Chemistry is often thought to be quite factual, and therefore might be considered close to the "positivist" ideal of a value-free science. A closer look, however, reveals that the field is coupled to the invisible realm of values, meanings, and purpose in various ways, and chemists interact with that realm loosely and unevenly. Tacit knowledge is one important locus of such interactions. We are concerned in this essay with two questions. What is the nature of the knowledge when we are in the early stages of discovery? and In what ways does the hidden reality we are seeking affect our search for an understanding of it? The first question is partly answered by Polanyi's theory of tacit knowledge, while the second one leads us to realize the limitations of our language when discussing "reality"-or certain chemical experimental results. A strictly positivist approach is of little use, but so is the opposite, the complete disregard of facts. The contrast between positivism and non-formulable aspects of scientific reasoning amounts to a paradox that needs to be analyzed and can lead to a "connected" chemistry. This in turn resembles networks described by Schweber and is more concerned than the chemistry "as it is" with aspects such as the image of chemistry, the challenges chemists face as citizens, and chemistry in liberal education.

  9. Presidential Green Chemistry Challenge: 2015 Greener Synthetic Pathways Award

    Science.gov (United States)

    Presidential Green Chemistry Challenge 2015 award winner, LanzaTech Inc. developed a method to utilize gas streams with a range of CO and H2 compositions to produce fuels such as ethanol and chemicals at high selectivities and yields

  10. Collaborative Physical Chemistry Projects Involving Computational Chemistry

    Science.gov (United States)

    Whisnant, David M.; Howe, Jerry J.; Lever, Lisa S.

    2000-02-01

    The physical chemistry classes from three colleges have collaborated on two computational chemistry projects using Quantum CAChe 3.0 and Gaussian 94W running on Pentium II PCs. Online communication by email and the World Wide Web was an important part of the collaboration. In the first project, students used molecular modeling to predict benzene derivatives that might be possible hair dyes. They used PM3 and ZINDO calculations to predict the electronic spectra of the molecules and tested the predicted spectra by comparing some with experimental measurements. They also did literature searches for real hair dyes and possible health effects. In the final phase of the project they proposed a synthetic pathway for one compound. In the second project the students were asked to predict which isomer of a small carbon cluster (C3, C4, or C5) was responsible for a series of IR lines observed in the spectrum of a carbon star. After preliminary PM3 calculations, they used ab initio calculations at the HF/6-31G(d) and MP2/6-31G(d) level to model the molecules and predict their vibrational frequencies and rotational constants. A comparison of the predictions with the experimental spectra suggested that the linear isomer of the C5 molecule was responsible for the lines.

  11. Reaction chemistry of cerium

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-01-01

    It is truly ironic that a synthetic organic chemist likely has far greater knowledge of the reaction chemistry of cerium(IV) than an inorganic colleague. Cerium(IV) reagents have long since been employed as oxidants in effecting a wide variety of organic transformations. Conversely, prior to the late 1980s, the number of well characterized cerium(IV) complexes did not extend past a handful of known species. Though in many other areas, interest in the molecular chemistry of the 4f-elements has undergone an explosive growth over the last twenty years, the chemistry of cerium(IV) has for the most part been overlooked. This report describes reactions of cerium complexes and structure.

  12. Air Composition and Chemistry

    Science.gov (United States)

    Brimblecombe, Peter

    1996-01-01

    This book is about the atmosphere and humanity's influence on it. For this new edition, Brimblecombe has rewritten and updated much of the book. In the early chapters, he discusses the geochemical, biological and maritime sources of the trace gases. Next, he examines the chemistry of atmospheric gases, suspended particles, and rainfall. After dealing with the natural atmosphere, he examines the sources of air pollution and its effects, with all scenarios updated from the last edition. Scenarios include decline in health, damage to plants and animals, indoor pollution, and acid rain. The final chapters, also revised, are concerned with the chemistry and evolution of the atmospheres of the planets of the solar system. Students with an interest in chemistry and the environmental sciences will find this book highly valuable.

  13. Mathematics for physical chemistry

    CERN Document Server

    Mortimer, Robert G

    2005-01-01

    Mathematics for Physical Chemistry, Third Edition, is the ideal text for students and physical chemists who want to sharpen their mathematics skills. It can help prepare the reader for an undergraduate course, serve as a supplementary text for use during a course, or serve as a reference for graduate students and practicing chemists. The text concentrates on applications instead of theory, and, although the emphasis is on physical chemistry, it can also be useful in general chemistry courses. The Third Edition includes new exercises in each chapter that provide practice in a technique immediately after discussion or example and encourage self-study. The first ten chapters are constructed around a sequence of mathematical topics, with a gradual progression into more advanced material. The final chapter discusses mathematical topics needed in the analysis of experimental data.* Numerous examples and problems interspersed throughout the presentations * Each extensive chapter contains a preview, objectives, and ...

  14. Deep learning for computational chemistry.

    Science.gov (United States)

    Goh, Garrett B; Hodas, Nathan O; Vishnu, Abhinav

    2017-06-15

    The rise and fall of artificial neural networks is well documented in the scientific literature of both computer science and computational chemistry. Yet almost two decades later, we are now seeing a resurgence of interest in deep learning, a machine learning algorithm based on multilayer neural networks. Within the last few years, we have seen the transformative impact of deep learning in many domains, particularly in speech recognition and computer vision, to the extent that the majority of expert practitioners in those field are now regularly eschewing prior established models in favor of deep learning models. In this review, we provide an introductory overview into the theory of deep neural networks and their unique properties that distinguish them from traditional machine learning algorithms used in cheminformatics. By providing an overview of the variety of emerging applications of deep neural networks, we highlight its ubiquity and broad applicability to a wide range of challenges in the field, including quantitative structure activity relationship, virtual screening, protein structure prediction, quantum chemistry, materials design, and property prediction. In reviewing the performance of deep neural networks, we observed a consistent outperformance against non-neural networks state-of-the-art models across disparate research topics, and deep neural network-based models often exceeded the "glass ceiling" expectations of their respective tasks. Coupled with the maturity of GPU-accelerated computing for training deep neural networks and the exponential growth of chemical data on which to train these networks on, we anticipate that deep learning algorithms will be a valuable tool for computational chemistry. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  15. Spins in chemistry

    CERN Document Server

    McWeeny, Roy

    2004-01-01

    Originally delivered as a series of lectures, this volume systematically traces the evolution of the ""spin"" concept from its role in quantum mechanics to its assimilation into the field of chemistry. Author Roy McWeeny presents an in-depth illustration of the deductive methods of quantum theory and their application to spins in chemistry, following the path from the earliest concepts to the sophisticated physical methods employed in the investigation of molecular structure and properties. Starting with the origin and development of the spin concept, the text advances to an examination of sp

  16. Solvent effects in chemistry

    CERN Document Server

    Buncel, Erwin

    2015-01-01

    This book introduces the concepts, theory and experimental knowledge concerning solvent effects on the rate and equilibrium of chemical reactions of all kinds.  It begins with basic thermodynamics and kinetics, building on this foundation to demonstrate how a more detailed understanding of these effects may be used to aid in determination of reaction mechanisms, and to aid in planning syntheses. Consideration is given to theoretical calculations (quantum chemistry, molecular dynamics, etc.), to statistical methods (chemometrics), and to modern day concerns such as ""green"" chemistry, where ut

  17. Chemistry WebBook

    Science.gov (United States)

    SRD 69 NIST Chemistry WebBook (Web, free access)   The NIST Chemistry WebBook contains: Thermochemical data for over 7000 organic and small inorganic compounds; thermochemistry data for over 8000 reactions; IR spectra for over 16,000 compounds; mass spectra for over 33,000 compounds; UV/Vis spectra for over 1600 compounds; electronic and vibrational spectra for over 5000 compounds; constants of diatomic molecules(spectroscopic data) for over 600 compounds; ion energetics data for over 16,000 compounds; thermophysical property data for 74 fluids.

  18. Chemistry of Transactinides

    Science.gov (United States)

    Kratz, J. V.

    In this chapter, the chemical properties of the man-made transactinide elements rutherfordium, Rf (element 104), dubnium, Db (element 105), seaborgium, Sg (element 106), bohrium, Bh (element 107), hassium, Hs (element 108), and copernicium, Cn (element 112) are reviewed, and prospects for chemical characterizations of even heavier elements are discussed. The experimental methods to perform rapid chemical separations on the time scale of seconds are presented and comments are given on the special situation with the transactinides where chemistry has to be studied with single atoms. It follows a description of theoretical predictions and selected experimental results on the chemistry of elements 104 through 108, and element 112.

  19. Chemistry in second life.

    Science.gov (United States)

    Lang, Andrew S I D; Bradley, Jean-Claude

    2009-10-23

    This review will focus on the current level on chemistry research, education, and visualization possible within the multi-user virtual environment of Second Life. We discuss how Second Life has been used as a platform for the interactive and collaborative visualization of data from molecules and proteins to spectra and experimental data. We then review how these visualizations can be scripted for immersive educational activities and real-life collaborative research. We also discuss the benefits of the social networking affordances of Second Life for both chemists and chemistry students.

  20. The chemistry of silicon

    CERN Document Server

    Rochow, E G; Emeléus, H J; Nyholm, Ronald

    1975-01-01

    Pergamon Texts in Organic Chemistry, Volume 9: The Chemistry of Silicon presents information essential in understanding the chemical properties of silicon. The book first covers the fundamental aspects of silicon, such as its nuclear, physical, and chemical properties. The text also details the history of silicon, its occurrence and distribution, and applications. Next, the selection enumerates the compounds and complexes of silicon, along with organosilicon compounds. The text will be of great interest to chemists and chemical engineers. Other researchers working on research study involving s

  1. Atmospheric pseudohalogen chemistry

    OpenAIRE

    Lary, D. J.

    2004-01-01

    There are at least three reasons why hydrogen cyanide is likely to be significant for atmospheric chemistry. The first is well known, HCN is a product and marker of biomass burning. However, if a detailed ion chemistry of lightning is considered then it is almost certain than in addition to lightning producing NOx, it also produces HOx and HCN. Unlike NOx and HOx, HCN is long-lived and could therefore ...

  2. Progress in physical chemistry

    CERN Document Server

    Hempelmann, Rolf

    2008-01-01

    Progress in Physical Chemistry is a collection of recent ""Review Articles"" published in the ""Zeitschrift für Physikalische Chemie"". The second volume of Progress in Physical Chemistry is a collection of thematically closely related minireview articles written by the members of the Collaborative Research Centre (SFB) 277 of the German Research Foundation (DFG). These articles are based on twelve years of intense coordinated research efforts. Central topics are the synthesis and the characterization of interface-dominated, i.e. nanostructured materials, mainly in the solid state but also as

  3. Chemistry in Second Life

    Directory of Open Access Journals (Sweden)

    Bradley Jean-Claude

    2009-10-01

    Full Text Available Abstract This review will focus on the current level on chemistry research, education, and visualization possible within the multi-user virtual environment of Second Life. We discuss how Second Life has been used as a platform for the interactive and collaborative visualization of data from molecules and proteins to spectra and experimental data. We then review how these visualizations can be scripted for immersive educational activities and real-life collaborative research. We also discuss the benefits of the social networking affordances of Second Life for both chemists and chemistry students.

  4. Chemistry in microelectronics

    CERN Document Server

    Le Tiec, Yannick

    2013-01-01

    Microelectronics is a complex world where many sciences need to collaborate to create nano-objects: we need expertise in electronics, microelectronics, physics, optics and mechanics also crossing into chemistry, electrochemistry, as well as biology, biochemistry and medicine. Chemistry is involved in many fields from materials, chemicals, gases, liquids or salts, the basics of reactions and equilibrium, to the optimized cleaning of surfaces and selective etching of specific layers. In addition, over recent decades, the size of the transistors has been drastically reduced while the functionalit

  5. Proof of comparable K-pair and pi -pair production from time-like photons of 15, 16, and 17 GeV and determination of the K-meson electromagnetic form factor

    CERN Document Server

    Bernardini, M; Brunini, P L; Fiorentino, E; Massam, Thomas; Monari, L; Palmonari, F; Rimondi, F; Zichichi, A

    1973-01-01

    The observation of 21 K/sup +/K/sup -/ pairs in 38 hadron pair events produced at 1.5, 1.6 and 1.7 GeV total centre-of-mass energies in e /sup +/e/sup -/ annihilations, establishes that time-like photons produce K pairs and pi pairs with comparable rates in this energy range. The K-meson electromagnetic form factor at a mean s-value of 2.4 GeV/sup 2/ is measured to be mod F/sub K/ mod =0.50+or-0.08. The number of e/sup +/e/sup -/ pairs observed in the same angular and energy range is 5148. (3 refs).

  6. Chemistry: Experiments, Demonstrations and Other Activities Suggested for Chemistry.

    Science.gov (United States)

    New York State Education Dept., Albany. Bureau of Secondary Curriculum Development.

    This publication is a handbook used in conjunction with the course of study in chemistry developed through the New York State Education Department and The University of the State of New York. It contains experiments, demonstrations, and other activities for a chemistry course. Areas covered include the science of chemistry, the atomic structure of…

  7. Connected Chemistry--Incorporating Interactive Simulations into the Chemistry Classroom.

    Science.gov (United States)

    Stieff, Mike; Wilensky, Uri

    2003-01-01

    Describes a novel modeling and simulation package and assesses its impact on students' understanding of chemistry. Connected Chemistry was implemented inside the NetLogo modeling environment. Using Connected Chemistry, students employed problem -solving techniques characterized by stronger attempts at conceptual understanding and logical…

  8. Myrrh--Commiphora chemistry.

    Science.gov (United States)

    Hanus, Lumír O; Rezanka, Tomás; Dembitsky, Valery M; Moussaieff, Arieh

    2005-06-01

    Myrrh and opopanax has been used throughout history in incense and as a perfume. Since Bible times it has been used for the treatment of wounds. The first attempts to identify content compounds were almost 100 years ago. In this review we discuss the present state of knowledge in the chemistry of substances of Commiphora spp.

  9. Elements of Chemistry

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 17; Issue 1. Elements of Chemistry. Antoine-Laurent Lavoisier. Classics Volume 17 Issue 1 January 2012 pp 92-100. Fulltext. Click here to view fulltext PDF. Permanent link: http://www.ias.ac.in/article/fulltext/reso/017/01/0092-0100. Author Affiliations.

  10. Chemistry and Heritage

    Science.gov (United States)

    Vittoria Barbarulo, Maria

    2014-05-01

    Chemistry is the central science, as it touches every aspect of the society we live in and it is intertwined with many aspects of our culture; in particular, the strong link between Chemistry and Archaeology and Art History is being explored, offering a penetrating insight into an area of growing interest from an educational point of view. A series of vital and vibrant examples (i.e., ancient bronzes composition, colour changes due to natural pigment decomposition, marble degradation) has been proposed, on one hand, to improve student understanding of the relationship between cultural and scientific issues arising from the examination, the conservation, and the maintenance of cultural Heritage, on the other, to illustrate the role of the underlying Chemistry. In some case studies, a survey of the most relevant atmospheric factors, which are involved in the deterioration mechanisms, has also been presented to the students. First-hand laboratory experiences have been providing an invaluable means of discovering the full and varied world of Chemistry. Furthermore, the promotion of an interdisciplinary investigation of a famous painting or fresco, involving the study of its nature and significance, the definition of its historical context, any related literature, the chemical knowledge of the materials used, may be an excellent occasion to experiment the Content and Language Integrated Learning (CLIL). The aim of this approach is to convey the important message that everyone has the responsibility to care for and preserve Heritage for the benefit of present and future generations.

  11. Concept of Green Chemistry

    Indian Academy of Sciences (India)

    Srimath

    Chemistry has provided valuable materials in the form of medi- cines, food products, cosmetics, dyes, paints, agrochemicals, biomolecules, high-tech substances like polymers, liquid crystals and nanoparticles. Chemists have used their knowledge and skill to prepare a large number of new materials which are far better.

  12. Chemistry at the Nanoscale

    Indian Academy of Sciences (India)

    Program, School of Medicine and Dentistry, University of. Rochester, New York. His research interests are in studying the structure, function, interaction and the chemistry of biomolecules as well as their assemblies and networks. Ram Ramaswamy teaches in the Schools of Physical. Sciences (SPS) and. Computational and.

  13. Chemistry in the Troposphere.

    Science.gov (United States)

    Chameides, William L.; Davis, Douglas D.

    1982-01-01

    Topics addressed in this review of chemistry in the troposphere (layer of atmosphere extending from earth's surface to altitude of 10-16km) include: solar radiation/winds; earth/atmosphere interface; kinetic studies of atmospheric reactions; tropospheric free-radical photochemistry; instruments for nitric oxide detection; sampling…

  14. Electrostatics in Chemistry

    Indian Academy of Sciences (India)

    For an excellent summary of the field of supramolecular chemistry, readers are referred to the article by J-M Lehn in Resonance, VaLl,. No.3, p.39, 1996. Electrostatics plays an important role in weak intermolecular interactions. The present series is aimed at understanding these electrostatic aspects. This article presents the.

  15. 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 ...

  16. The Chemistry of Griseofulvin

    DEFF Research Database (Denmark)

    Petersen, Asger Bjørn; Rønnest, Mads Holger; Larsen, Thomas Ostenfeld

    2014-01-01

    Specific synthetic routes are presented in schemes to illustrate the chemistry, and the analogs are presented in a table format to give an accessible overview of the structures. Several patents have been published regarding the properties of griseofulvin and its derivatives including synthesis...

  17. Tunnelling Effects in Chemistry

    Indian Academy of Sciences (India)

    IAS Admin

    Tunnelling Effects in Chemistry. Molecules in the Strange Quantum World. Sharmistha Karmakar, Deepthi Jose and Ayan Datta. (left) Sharmistha Karmakar is doing her PhD in the group of. Ayan Datta, IACS,. Kolkata. Her research interests are modelling molecules with strong optical absorbtion and emission properties.

  18. Analytical Chemistry Laboratory

    Science.gov (United States)

    Anderson, Mark

    2013-01-01

    The Analytical Chemistry and Material Development Group maintains a capability in chemical analysis, materials R&D failure analysis and contamination control. The uniquely qualified staff and facility support the needs of flight projects, science instrument development and various technical tasks, as well as Cal Tech.

  19. Forensic Chemistry Training

    Directory of Open Access Journals (Sweden)

    Zuhal GERÇEK

    2012-01-01

    Full Text Available Increasing the types of terrorism and crime nowadays, the importance of the forensic sciences can be bett er understood. Forensic science is the application of the wide spectrum of science to answer the question of legal system. It contains the application of the principles, techniques and methods of basic sciences and its main aim is the determination of the physical facts which are important in legal situations. Forensic chemistry is the branch of chemistry which performs the chemical analysis of evidences that used in the courts. Forensic chemist is the professional chemist who analyzes the evidences from crime scene and reaches a result by application of tests. Th us, they have to have a special education. In forensic laboratories candidates who have chemistry/biochemistry undergraduate degree and took biology and forensic chemistry lectures are preferred. It is necessary to design graduate and undergraduate education to train a forensic chemist. Science education should be at the core of the undergraduate education. In addition to this strong laboratory education on both science and forensic science should be given. Th e graduate program of forensic science example should contain forensic science subjects, strong academic lectures on special subjects and research and laboratory components.

  20. Chemistry: The Middle Kingdom

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 12; Issue 7. Chemistry: The Middle Kingdom. Gautam R Desiraju. General Article Volume 12 Issue 7 July 2007 pp 44-60. Fulltext. Click here to view fulltext PDF. Permanent link: http://www.ias.ac.in/article/fulltext/reso/012/07/0044-0060. Keywords.

  1. Symmetry in chemistry

    CERN Document Server

    Jaffé, Hans H

    1977-01-01

    This book, devoted exclusively to symmetry in chemistry and developed in an essentially nonmathematical way, is a must for students and researchers. Topics include symmetry elements and operations, multiple symmetry operations, multiplication tables and point groups, group theory applications, and crystal symmetry. Extensive appendices provide useful tables.

  2. Array processors in chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Ostlund, N.S.

    1980-01-01

    The field of attached scientific processors (''array processors'') is surveyed, and an attempt is made to indicate their present and possible future use in computational chemistry. The current commercial products from Floating Point Systems, Inc., Datawest Corporation, and CSP, Inc. are discussed.

  3. Teaching Chemistry. through Riddles

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 9; Issue 7. Teaching Chemistry through Riddles. Mala Das Sharma. Classroom Volume 9 Issue 7 July 2004 pp 74-76. Fulltext. Click here to view fulltext PDF. Permanent link: http://www.ias.ac.in/article/fulltext/reso/009/07/0074-0076. Author Affiliations.

  4. Arrows in Chemistry

    Indian Academy of Sciences (India)

    IAS Admin

    reaction conditions, reagents and catalysts used in the chemical reaction are written on the chemical reaction arrow. For example,. Arrows in chemistry can be broadly classified as 'reaction arrows' and 'electron arrows'. While the former is used to describe the state or progress of a chemical reaction, the latter is used to.

  5. Tunnelling Effects in Chemistry

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 19; Issue 2. Tunnelling Effects in Chemistry: Molecules in the Strange Quantum World. Sharmistha Karmakar Deepthi Jose Ayan Datta. General Article Volume 19 Issue 2 February 2014 pp 160-174 ...

  6. Chemistry in a Nutshell.

    Science.gov (United States)

    Rupnow, John; And Others

    1995-01-01

    Presents an activity that involves making peanut butter in the laboratory as a way to teach students the chemistry concepts of emulsification, solubility, and formulation. Enables students to realize that they can actually create or modify the physical and sensory characteristics of peanut butter and taste the differences in their work. (JRH)

  7. Nobel Prize in Chemistry

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 9; Issue 4. Nobel Prize in Chemistry – 2003 The Gateway for Perfect Health. S M Srideshikan S K Srivatsa. General Article Volume 9 Issue 4 April 2004 pp 61-70. Fulltext. Click here to view fulltext PDF. Permanent link:

  8. Chemistry of Materials

    Indian Academy of Sciences (India)

    solid materials particularly metal oxides of various kinds. Then started intense activity in other classes of materials, including organics. It is no surprise that in the last few years, the two main streams of chemistry are directed towards biology and advanced materials. It is also not difficult to understand why chemists are getting ...

  9. Arrows in Chemistry

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 15; Issue 1. Arrows in Chemistry. Abirami Lakshminarayanan. General Article Volume 15 Issue 1 January 2010 pp 51-63. Fulltext. Click here to view fulltext PDF. Permanent link: http://www.ias.ac.in/article/fulltext/reso/015/01/0051-0063. Keywords. Arrows ...

  10. Electrostatics in Chemistry

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 4; Issue 2. Electrostatics in Chemistry - Basic Principles. Shridhar R Gadre Pravin K Bhadane. Series Article Volume 4 Issue 2 February 1999 pp 8-19. Fulltext. Click here to view fulltext PDF. Permanent link:

  11. Chemistry: The Middle Kingdom

    Indian Academy of Sciences (India)

    2005-02-10

    Feb 10, 2005 ... Chemistry occupies a unique middle position between physics and mathematics on the one side and biology, .... The late nineteenth century saw the zenith of the industrial revolution, the emergence of capitalism and colo- .... of the processes occurring in living systems. Chemists were slow to recognize the ...

  12. Supramolecular analytical chemistry.

    Science.gov (United States)

    Anslyn, Eric V

    2007-02-02

    A large fraction of the field of supramolecular chemistry has focused in previous decades upon the study and use of synthetic receptors as a means of mimicking natural receptors. Recently, the demand for synthetic receptors is rapidly increasing within the analytical sciences. These classes of receptors are finding uses in simple indicator chemistry, cellular imaging, and enantiomeric excess analysis, while also being involved in various truly practical assays of bodily fluids. Moreover, one of the most promising areas for the use of synthetic receptors is in the arena of differential sensing. Although many synthetic receptors have been shown to yield exquisite selectivities, in general, this class of receptor suffers from cross-reactivities. Yet, cross-reactivity is an attribute that is crucial to the success of differential sensing schemes. Therefore, both selective and nonselective synthetic receptors are finding uses in analytical applications. Hence, a field of chemistry that herein is entitled "Supramolecular Analytical Chemistry" is emerging, and is predicted to undergo increasingly rapid growth in the near future.

  13. Colour chemistry in water

    OpenAIRE

    Cardona, Maria

    2015-01-01

    Atmospheric carbon dioxide (CO2) levels have increased dramatically in the last few decades. Famous for causing global warming, CO2 is also resulting in the acidification of seas and oceans. http://www.um.edu.mt/think/colour-chemistry-in-water/

  14. African mistletoes (loranthaceae); ethnopharmacology, chemistry ...

    African Journals Online (AJOL)

    African mistletoes (loranthaceae); ethnopharmacology, chemistry and medicinal values: An update. ... little is known about their biology (taxonomy, host/plant relationship, ecology, toxicology, physiological characteristics, etc.) and chemistry (chemical constituents' profile). Some pharmacological studies carried out on the ...

  15. Polymer Chemistry in High School.

    Science.gov (United States)

    Stucki, Roger

    1984-01-01

    Discusses why polymer chemistry should be added to the general chemistry curriculum and what topics are appropriate (listing traditional with related polymer topics). Also discusses when and how these topics should be taught. (JN)

  16. Mathematical problems for chemistry students

    CERN Document Server

    Pota, Gyorgy

    2011-01-01

    Mathematical Problems for Chemistry Students has been compiled and written (a) to help chemistrystudents in their mathematical studies by providing them with mathematical problems really occurring in chemistry (b) to help practising chemists to activate their applied mathematical skills and (c) to introduce students and specialistsof the chemistry-related fields (physicists, mathematicians, biologists, etc.) intothe world of the chemical applications.Some problems of the collection are mathematical reformulations of those in the standard textbooks of chemistry, others we

  17. Aqueous Solution Chemistry of Plutonium

    Energy Technology Data Exchange (ETDEWEB)

    Clark, David L. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2014-01-28

    Things I have learned working with plutonium: Chemistry of plutonium is complex; Redox equilibria make Pu solution chemistry particularly challenging in the absence of complexing ligands; Understanding this behavior is key to successful Pu chemistry experiments; There is no suitable chemical analog for plutonium.

  18. Six Pillars of Organic Chemistry

    Science.gov (United States)

    Mullins, Joseph J.

    2008-01-01

    This article describes an approach to teaching organic chemistry, which is to have students build their knowledge of organic chemistry upon a strong foundation of the fundamental concepts of the subject. Specifically, the article focuses upon a core set of concepts that I call "the six pillars of organic chemistry": electronegativity, polar…

  19. MINIATURIZING CHEMISTRY THE ECOLOGICAL ALTERNATIVE

    African Journals Online (AJOL)

    unesco

    Education in Chemistry (U.K.). • African Journal of Chemical Education (Ethiopia). • Educacion Quimica (Mexico). A list of books on the field is given in the appendix of this paper. WHERE DID IT START AND WHERE IS IT BEING USED? The adoption of Microscale Chemistry for the teaching of Chemistry in Africa and Asia is.

  20. Division of Analytical Chemistry, 1998

    DEFF Research Database (Denmark)

    Hansen, Elo Harald

    1999-01-01

    The article recounts the 1998 activities of the Division of Analytical Chemistry (DAC- formerly the Working Party on Analytical Chemistry, WPAC), which body is a division of the Federation of European Chemical Societies (FECS). Elo Harald Hansen is the Danish delegate, representing The Danish...... Chemical Society/The Society for Analytical Chemistry....

  1. Interactions of Chemistry Teachers with Gifted Students in a Regular High-School Chemistry Classroom

    Science.gov (United States)

    Benny, Naama; Blonder, Ron

    2018-01-01

    Regular high-school chemistry teachers view gifted students as one of several types of students in a regular (mixed-ability) classroom. Gifted students have a range of unique abilities that characterize their learning process: mostly they differ in three key learning aspects: their faster learning pace, increased depth of understanding, and…

  2. 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.

  3. General Dialdehyde Click Chemistry for Amine Bioconjugation.

    Science.gov (United States)

    Elahipanah, Sina; O'Brien, Paul J; Rogozhnikov, Dmitry; Yousaf, Muhammad N

    2017-05-17

    The development of methods for conjugating a range of molecules to primary amine functional groups has revolutionized the fields of chemistry, biology, and material science. The primary amine is a key functional group and one of the most important nucleophiles and bases used in all of synthetic chemistry. Therefore, tremendous interest in the synthesis of molecules containing primary amines and strategies to devise chemical reactions to react with primary amines has been at the core of chemical research. In particular, primary amines are a ubiquitous functional group found in biological systems as free amino acids, as key side chain lysines in proteins, and in signaling molecules and metabolites and are also present in many natural product classes. Due to its abundance, the primary amine is the most convenient functional group handle in molecules for ligation to other molecules for a broad range of applications that impact all scientific fields. Because of the primary amine's central importance in synthetic chemistry, acid-base chemistry, redox chemistry, and biology, many methods have been developed to efficiently react with primary amines, including activated carboxylic acids, isothiocyanates, Michael addition type systems, and reaction with ketones or aldehydes followed by in situ reductive amination. Herein, we introduce a new traceless, high-yield, fast click-chemistry method based on the rapid and efficient trapping of amine groups via a functionalized dialdehyde group. The click reaction occurs in mild conditions in organic solvents or aqueous media and proceeds in high yield, and the starting dialdehyde reagent and resulting dialdehyde click conjugates are stable. Moreover, no catalyst or dialdehyde-activating group is required, and the only byproduct is water. The initial dialdehyde and the resulting conjugate are both straightforward to characterize, and the reaction proceeds with high atom economy. To demonstrate the broad scope of this new click

  4. 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…

  5. Chemistry of naphthalene diimides.

    Science.gov (United States)

    Bhosale, Sheshanath V; Jani, Chintan H; Langford, Steven J

    2008-02-01

    This tutorial review surveys recent developments in the chemistry of naphthalene diimides (NDIs) and explores their application in the fields of material and supramolecular science. It begins with a discussion of their general uses, methods of syntheses and their electronic and spectroscopic properties. Of interest to their application in the fields of conducting thin films and molecular sensors is the structure-function relationships that exist either as co-components of supramolecular ensembles as in the case of "nanotubes", or as the sole components in molecular wires. Also discussed are advances in NDI research within the areas of energy and electron transfer (covalent and non-covalent systems) and in host-guest chemistry including foldamer, mechanically-interlocked and ligand-gated ion channel examples. Finally, we explore the developments in the recent field of core-substituted NDIs, their photophysical properties and applications in artificial photosynthesis. We conclude with our views on the prospects of NDIs for future research endeavours.

  6. Organic Chemistry in Space

    Science.gov (United States)

    Charnley, Steven

    2009-01-01

    Astronomical observations, theoretical modeling, laboratory simulation and analysis of extraterrestrial material have enhanced our knowledge of the inventory of organic matter in the interstellar medium (ISM) and on small bodies such as comets and asteroids (Ehrenfreund & Charnley 2000). Comets, asteroids and their fragments, meteorites and interplanetary dust particles (IDPs), contributed significant amounts of extraterrestrial organic matter to the young Earth. This material degraded and reacted in a terrestrial prebiotic chemistry to form organic structures that may have served as building blocks for life on the early Earth. In this talk I will summarize our current understanding of the organic composition and chemistry of interstellar clouds. Molecules of astrobiological relevance include the building blocks of our genetic material: nucleic acids, composed of subunits such as N-heterocycles (purines and pyrimidines), sugars and amino acids. Signatures indicative of inheritance of pristine and modified interstellar material in comets and meteorites will also be discussed.

  7. Chemistry and Art.

    Science.gov (United States)

    Lipscher, Juraj

    2018-02-01

    This review summarizes possibilities of including scientific methods for investigation of art objects into the secondary school chemistry curriculum. We discuss methods such as X-ray radiography, infrared reflectography, neutron activation autoradiography, X-ray fluorescence, and Raman spectroscopy and provide recent examples of their use. The results obtained, especially when combined with modern digital image processing algorithms, are indeed impressive. The second part of the paper is devoted to suggestions for actual use in teaching. The activities in the classroom can be centered around scientific investigation of a single painting, properties and use of a single pigment, or utilizing parallels in the history of Chemistry and history of Art. Finally, scientific methods for detecting art fraud including actual historical examples are especially motivating for the students and various teaching activities can be designed around this aspect.

  8. Chemistry space–time

    Directory of Open Access Journals (Sweden)

    David A. Winkler

    2015-12-01

    Full Text Available As Einstein identified so clearly, space and time are intimately related. We discuss the relationship between time and Euclidean space using spectroscopic and radioastronomical studies of interstellar chemistry as an example. Given the finite speed of light, we are clearly studying chemical reactions occurring tens of thousands of years ago that may elucidate the primordial chemistry of this planet several billion years ago. We also explore space of a different kind – chemical space, with many more dimensions than the four we associate as space–time. Vast chemical spaces also need very efficient (computational methods for their exploration to overcome this ‘curse of dimensionality’. We discuss methods by which the time to explore these new spaces can be very substantially reduced, opening the discovery useful new materials that are the key to our future.

  9. Bubble and foam chemistry

    CERN Document Server

    Pugh, Robert J

    2016-01-01

    This indispensable guide will equip the reader with a thorough understanding of the field of foaming chemistry. Assuming only basic theoretical background knowledge, the book provides a straightforward introduction to the principles and properties of foams and foaming surfactants. It discusses the key ideas that underpin why foaming occurs, how it can be avoided and how different degrees of antifoaming can be achieved, and covers the latest test methods, including laboratory and industrial developed techniques. Detailing a variety of different kinds of foams, from wet detergents and food foams, to polymeric, material and metal foams, it connects theory to real-world applications and recent developments in foam research. Combining academic and industrial viewpoints, this book is the definitive stand-alone resource for researchers, students and industrialists working on foam technology, colloidal systems in the field of chemical engineering, fluid mechanics, physical chemistry, and applied physics.

  10. Carbohydrates in Supramolecular Chemistry.

    Science.gov (United States)

    Delbianco, Martina; Bharate, Priya; Varela-Aramburu, Silvia; Seeberger, Peter H

    2016-02-24

    Carbohydrates are involved in a variety of biological processes. The ability of sugars to form a large number of hydrogen bonds has made them important components for supramolecular chemistry. We discuss recent advances in the use of carbohydrates in supramolecular chemistry and reveal that carbohydrates are useful building blocks for the stabilization of complex architectures. Systems are presented according to the scaffold that supports the glyco-conjugate: organic macrocycles, dendrimers, nanomaterials, and polymers are considered. Glyco-conjugates can form host-guest complexes, and can self-assemble by using carbohydrate-carbohydrate interactions and other weak interactions such as π-π interactions. Finally, complex supramolecular architectures based on carbohydrate-protein interactions are discussed.

  11. Quo vadis, analytical chemistry?

    Science.gov (United States)

    Valcárcel, Miguel

    2016-01-01

    This paper presents an open, personal, fresh approach to the future of Analytical Chemistry in the context of the deep changes Science and Technology are anticipated to experience. Its main aim is to challenge young analytical chemists because the future of our scientific discipline is in their hands. A description of not completely accurate overall conceptions of our discipline, both past and present, to be avoided is followed by a flexible, integral definition of Analytical Chemistry and its cornerstones (viz., aims and objectives, quality trade-offs, the third basic analytical reference, the information hierarchy, social responsibility, independent research, transfer of knowledge and technology, interfaces to other scientific-technical disciplines, and well-oriented education). Obsolete paradigms, and more accurate general and specific that can be expected to provide the framework for our discipline in the coming years are described. Finally, the three possible responses of analytical chemists to the proposed changes in our discipline are discussed.

  12. Recent Advances in the Chemistry of Pentafulvenes.

    Science.gov (United States)

    Preethalayam, Preethanuj; Krishnan, K Syam; Thulasi, Sreeja; Chand, S Sarath; Joseph, Jomy; Nair, Vijay; Jaroschik, Florian; Radhakrishnan, K V

    2017-03-08

    Pentafulvenes are a unique class of compounds that originally attracted attention due to their propensity to display nonbenzenoid aromaticity. Subsequently, they were recognized as valuable synthons for the construction of a wide range of compounds by virtue of their ability to display multiple cycloaddition profiles. Naturally, this area of organic chemistry has experienced rapid growth over the last five decades, fueled by elegant work showcasing the unique reactivity of pentafulvenes in a plethora of cycloaddition reactions. In this Review, we have attempted to provide a systematic account of the methods for the generation of pentafulvenes, their rich and varied cycloaddition chemistry, organometallic reactions, and theoretical studies that support their versatility. Further, we have highlighted their applications in the synthesis of a variety of complex structural frameworks. It is our conviction that this Review will be useful to a wide range of chemists, and will spur further research in this promising area.

  13. Quantum mechanics in chemistry

    CERN Document Server

    Schatz, George C

    2002-01-01

    Intended for graduate and advanced undergraduate students, this text explores quantum mechanical techniques from the viewpoint of chemistry and materials science. Dynamics, symmetry, and formalism are emphasized. An initial review of basic concepts from introductory quantum mechanics is followed by chapters examining symmetry, rotations, and angular momentum addition. Chapter 4 introduces the basic formalism of time-dependent quantum mechanics, emphasizing time-dependent perturbation theory and Fermi's golden rule. Chapter 5 sees this formalism applied to the interaction of radiation and matt

  14. Green chemistry: development trajectory

    Science.gov (United States)

    Moiseev, I. I.

    2013-07-01

    Examples of applications of green chemistry methods in heavy organic synthesis are analyzed. Compounds, which can be produced by the processing of the biomass, and the criteria for the selection of the most promising products are summarized. The current status of the ethanol production and processing is considered. The possibilities of the use of high fatty acid triglycerides, glycerol, succinic acid, and isoprene are briefly discussed. The bibliography includes 67 references.

  15. Genetic algorithm in chemistry.

    OpenAIRE

    da Costa, PA; Poppi, RJ

    1999-01-01

    Genetic algorithm is an optimization technique based on Darwin evolution theory. In last years its application in chemistry is increasing significantly due the special characteristics for optimization of complex systems. The basic principles and some further modifications implemented to improve its performance are presented, as well as a historical development. A numerical example of a function optimization is also shown to demonstrate how the algorithm works in an optimization process. Final...

  16. Analytical Chemistry in Russia.

    Science.gov (United States)

    Zolotov, Yuri

    2016-09-06

    Research in Russian analytical chemistry (AC) is carried out on a significant scale, and the analytical service solves practical tasks of geological survey, environmental protection, medicine, industry, agriculture, etc. The education system trains highly skilled professionals in AC. The development and especially manufacturing of analytical instruments should be improved; in spite of this, there are several good domestic instruments and other satisfy some requirements. Russian AC has rather good historical roots.

  17. Chemistry of superheavy elements

    Energy Technology Data Exchange (ETDEWEB)

    Schaedel, M. [Japan Atomic Energy Agency, Tokai, Ibaraki (Japan). Advanced Science Research Center; GSI Helmholtz Center for Heavy Ion Research, Darmstadt (Germany)

    2012-07-01

    The chemistry of superheavy elements - or transactinides from their position in the Periodic Table - is summarized. After giving an overview over historical developments, nuclear aspects about synthesis of neutron-rich isotopes of these elements, produced in hot-fusion reactions, and their nuclear decay properties are briefly mentioned. Specific requirements to cope with the one-atom-at-a-time situation in automated chemical separations and recent developments in aqueous-phase and gas-phase chemistry are presented. Exciting, current developments, first applications, and future prospects of chemical separations behind physical recoil separators ('pre-separator') are discussed in detail. The status of our current knowledge about the chemistry of rutherfordium (Rf, element 104), dubnium (Db, element 105), seaborgium (Sg, element 106), bohrium (Bh, element 107), hassium (Hs, element 108), copernicium (Cn, element 112), and element 114 is discussed from an experimental point of view. Recent results are emphasized and compared with empirical extrapolations and with fully-relativistic theoretical calculations, especially also under the aspect of the architecture of the Periodic Table. (orig.)

  18. 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.

  19. Opportunities at the interface of chemistry and biology.

    Science.gov (United States)

    Martin, A B; Schultz, P G

    1999-12-01

    The combination of the tools and principles of chemistry, together with the tools of modern molecular biology, allow us to create complex synthetic and natural molecules, and processes with novel biological, chemical and physical properties. This article illustrates the tremendous opportunity that lies at this interface of chemistry and biology by describing a number of examples, ranging from efforts to expand the genetic code of living organisms to the use of combinatorial methods to generate biologically active synthetic molecules.

  20. Analytical Chemistry Division's sample transaction system

    Energy Technology Data Exchange (ETDEWEB)

    Stanton, J.S.; Tilson, P.A.

    1980-10-01

    The Analytical Chemistry Division uses the DECsystem-10 computer for a wide range of tasks: sample management, timekeeping, quality assurance, and data calculation. This document describes the features and operating characteristics of many of the computer programs used by the Division. The descriptions are divided into chapters which cover all of the information about one aspect of the Analytical Chemistry Division's computer processing.

  1. 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...

  2. Deep learning for computational chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Goh, Garrett B. [Advanced Computing, Mathematics, and Data Division, Pacific Northwest National Laboratory, 902 Battelle Blvd Richland Washington 99354; Hodas, Nathan O. [Advanced Computing, Mathematics, and Data Division, Pacific Northwest National Laboratory, 902 Battelle Blvd Richland Washington 99354; Vishnu, Abhinav [Advanced Computing, Mathematics, and Data Division, Pacific Northwest National Laboratory, 902 Battelle Blvd Richland Washington 99354

    2017-03-08

    The rise and fall of artificial neural networks is well documented in the scientific literature of both the fields of computer science and computational chemistry. Yet almost two decades later, we are now seeing a resurgence of interest in deep learning, a machine learning algorithm based on “deep” neural networks. Within the last few years, we have seen the transformative impact of deep learning the computer science domain, notably in speech recognition and computer vision, to the extent that the majority of practitioners in those field are now regularly eschewing prior established models in favor of deep learning models. In this review, we provide an introductory overview into the theory of deep neural networks and their unique properties as compared to traditional machine learning algorithms used in cheminformatics. By providing an overview of the variety of emerging applications of deep neural networks, we highlight its ubiquity and broad applicability to a wide range of challenges in the field, including QSAR, virtual screening, protein structure modeling, QM calculations, materials synthesis and property prediction. In reviewing the performance of deep neural networks, we observed a consistent outperformance against non neural networks state-of-the-art models across disparate research topics, and deep neural network based models often exceeded the “glass ceiling” expectations of their respective tasks. Coupled with the maturity of GPU-accelerated computing for training deep neural networks and the exponential growth of chemical data on which to train these networks on, we anticipate that deep learning algorithms will be a useful tool and may grow into a pivotal role for various challenges in the computational chemistry field.

  3. Biginelli and Mannich multicomponent reactions in the undergraduate organic chemistry laboratory: a didactic approach to green chemistry principles

    OpenAIRE

    Marcelo Volpatto Marques; Tula Beck Bisol; Marcus Mandolesi Sá

    2012-01-01

    The introduction of Mannich and Biginelli multicomponent reactions in a practical Organic Chemistry course is presented in this article. Procedures described in the literature were adapted for use under the simple conditions available in undergraduate laboratories and were selected on the basis of Green Chemistry principles and practicality of synthesis. The reactions are easy to carry out and all products are readily isolated as crystalline solids with yields ranging from moderate to high.

  4. Mars aqueous chemistry experiment

    Science.gov (United States)

    Clark, Benton C.; Mason, Larry W.

    1993-01-01

    The Mars Aqueous Chemistry Experiment (MACE) is designed to conduct a variety of measurements on regolith samples, encompassing mineral phase analyses, chemical interactions with H2O, and physical properties determinations. From these data, much can be learned or inferred regarding the past weathering environment, the contemporaneous soil micro-environments, and the general chemical and physical state of the Martian regolith. By analyzing both soil and duricrust samples, the nature of the latter may become more apparent. Sites may be characterized for comparative purposes and criteria could be set for selection of high priority materials on future sample return missions. Progress for the first year MACE PIDDP is reported in two major areas of effort: (1) fluids handling concepts, definition, and breadboard fabrication and (2) aqueous chemistry ion sensing technology and test facility integration. A fluids handling breadboard was designed, fabricated, and tested at Mars ambient pressure. The breadboard allows fluid manipulation scenarios to be tested under the reduced pressure conditions expected in the Martian atmosphere in order to validate valve operations, orchestrate analysis sequences, investigate sealing integrity, and to demonstrate efficacy of the fluid handling concept. Additional fluid manipulation concepts have also been developed based on updated MESUR spacecraft definition. The Mars Aqueous Chemistry Experiment Ion Selective Electrode (ISE) facility was designed as a test bed to develop a multifunction interface for measurements of chemical ion concentrations in aqueous solution. The interface allows acquisition of real time data concerning the kinetics and heats of salt dissolution, and transient response to calibration and solubility events. An array of ion selective electrodes has been interfaced and preliminary calibration studies performed.

  5. Allicin: chemistry and biological properties.

    Science.gov (United States)

    Borlinghaus, Jan; Albrecht, Frank; Gruhlke, Martin C H; Nwachukwu, Ifeanyi D; Slusarenko, Alan J

    2014-08-19

    Allicin (diallylthiosulfinate) is a defence molecule from garlic (Allium sativum L.) with a broad range of biological activities. Allicin is produced upon tissue damage from the non-proteinogenic amino acid alliin (S-allylcysteine sulfoxide) in a reaction that is catalyzed by the enzyme alliinase. Current understanding of the allicin biosynthetic pathway will be presented in this review. Being a thiosulfinate, allicin is a reactive sulfur species (RSS) and undergoes a redox-reaction with thiol groups in glutathione and proteins that is thought to be essential for its biological activity. Allicin is physiologically active in microbial, plant and mammalian cells. In a dose-dependent manner allicin can inhibit the proliferation of both bacteria and fungi or kill cells outright, including antibiotic-resistant strains like methicillin-resistant Staphylococcus aureus (MRSA). Furthermore, in mammalian cell lines, including cancer cells, allicin induces cell-death and inhibits cell proliferation. In plants allicin inhibits seed germination and attenuates root-development. The majority of allicin's effects are believed to be mediated via redox-dependent mechanisms. In sub-lethal concentrations, allicin has a variety of health-promoting properties, for example cholesterol- and blood pressure-lowering effects that are advantageous for the cardio-vascular system. Clearly, allicin has wide-ranging and interesting applications in medicine and (green) agriculture, hence the detailed discussion of its enormous potential in this review. Taken together, allicin is a fascinating biologically active compound whose properties are a direct consequence of the molecule's chemistry.

  6. Principles of Chemistry (by Michael Munowitz)

    Science.gov (United States)

    Kovac, Reviewed By Jeffrey

    2000-05-01

    principles. This is a very conceptual book. Each chapter has two parts, which are distinguished by having different-colored pages: white and gray. The first part of every chapter is a lovely conceptual development of the "big picture". In these white pages, there are no sample problems, no tables of data, just elegant prose liberally illustrated with graphs and diagrams. Mathematical and chemical equations and chemical structures are presented as needed, but the goal is to provide the reader with a conceptual understanding. I found these introductory "lectures", as Munowitz terms them, to be enchanting. The second part of each chapter is a review and guide to problems, what Munowitz calls the "recitation" section. These pages are gray. This second section gives a brief summary of the material, which is followed by a series of worked examples that apply the concepts to practical problems. This structure reflects the author's pedagogical philosophy--begin with the general and move to the specific--and his view of chemistry as a combination of "lofty principles and gritty practicality". Following the worked examples, of course, are exercises for the student, ranging from simple drill problems to more sophisticated applications of the principles. I was a little disappointed, however, that there were so few conceptual exercises. Although Munowitz describes the second part of each chapter as a review and applications, he does put new material into the sample problems. For example, in Chapter 3 the concept of oxidation numbers is introduced and sample problems on the assignment of oxidation numbers are presented. Then, in example 3-3, the concept of formal charge is presented as a contrast to the oxidation number even though this idea had not been previously introduced. The dual structure of white and gray pages makes this book unique but also very long. The combined length of the white sections is about 800 pages, but an approximately 25-page conceptual section is always followed

  7. Chemistry in aircraft plumes

    Energy Technology Data Exchange (ETDEWEB)

    Kraabol, A.G.; Stordal, F.; Knudsen, S. [Norwegian Inst. for Air Research, Kjeller (Norway); Konopka, P. [Deutsche Forschungsanstalt fuer Luft- und Raumfahrt e.V. (DLR), Wessling (Germany). Inst. fuer Physik der Atmosphaere

    1997-12-31

    An expanding plume model with chemistry has been used to study the chemical conversion of NO{sub x} to reservoir species in aircraft plumes. The heterogeneous conversion of N{sub 2}O{sub 5} to HNO{sub 3}(s) has been investigated when the emissions take place during night-time. The plume from an B747 has been simulated. During a ten-hour calculation the most important reservoir species was HNO{sub 3} for emissions at noon. The heterogeneous reactions had little impact on the chemical loss of NO{sub x} to reservoir species for emissions at night. (author) 4 refs.

  8. Chemistry and Science Fiction

    Science.gov (United States)

    Stocker, Jack H.

    1998-11-01

    This lively collection looks at science as filtered through literature, film, and television. It discusses classic works in science fiction and provides an in-depth look at the chemistry depicted in popular culture, particularly in Start Trek , Star Wars , and Doctor Who . It includes an examination by Nebula Award winner Connie Willis of how science fiction authors use science, and reprints two tongue-in-cheek short stories by Isaac Asimov. The book also includes suggestions for using science fiction as an educational resource.

  9. Chemistry in space

    CERN Document Server

    Rehder, Dieter

    2010-01-01

    The dynamic field of extraterrestrial chemistry brings together ideas of chemistr, astrophysics, and biology to the study of molecules between stars, around stars, and on plantes. This book serves as an introduction to chemial processes under ?unearthly? and hence usually extreme conditions (temperature, pressure, high or low density, bombardment by cosmic rays), and their impact on the early development of our solar system, as well as providing a deeper understanding of processes in earthly regions where conditions approach those of extraterrestrial areas.A unique and extraordinary perspe

  10. Introduction to Coordination Chemistry

    CERN Document Server

    Lawrance, Geoffrey Alan

    2010-01-01

    Introduction to Coordination Chemistry examines and explains how metals and molecules that bind as ligands interact, and the consequences of this assembly process. This book describes the chemical and physical properties and behavior of the complex assemblies that form, and applications that may arise as a result of these properties. Coordination complexes are an important but often hidden part of our world?even part of us?and what they do is probed in this book. This book distills the essence of this topic for undergraduate students and for research scientists.

  11. Principles of quantum chemistry

    CERN Document Server

    George, David V

    2013-01-01

    Principles of Quantum Chemistry focuses on the application of quantum mechanics in physical models and experiments of chemical systems.This book describes chemical bonding and its two specific problems - bonding in complexes and in conjugated organic molecules. The very basic theory of spectroscopy is also considered. Other topics include the early development of quantum theory; particle-in-a-box; general formulation of the theory of quantum mechanics; and treatment of angular momentum in quantum mechanics. The examples of solutions of Schroedinger equations; approximation methods in quantum c

  12. Radiochemistry and nuclear chemistry

    CERN Document Server

    Choppin, Gregory; RYDBERG, JAN; Ekberg, Christian

    2013-01-01

    Radiochemistry or nuclear chemistry is the study of radiation from an atomic and molecular perspective, including elemental transformation and reaction effects, as well as physical, health and medical properties. This revised edition of one of the earliest and best-known books on the subject has been updated to bring into teaching the latest developments in research and the current hot topics in the field. To further enhance the functionality of this text, the authors have added numerous teaching aids, examples in MathCAD with variable quantities and options, hotlinks to relevant text secti

  13. Quantum chemistry an introduction

    CERN Document Server

    Kauzmann, Walter

    2013-01-01

    Quantum Chemistry: An Introduction provides information pertinent to the fundamental aspects of quantum mechanics. This book presents the theory of partial differentiation equations by using the classical theory of vibrations as a means of developing physical insight into this essential branch of mathematics.Organized into five parts encompassing 16 chapters, this book begins with an overview of how quantum mechanical deductions are made. This text then describes the achievements and limitations of the application of quantum mechanics to chemical problems. Other chapters provide a brief survey

  14. Nuclear Chemistry and Services

    Energy Technology Data Exchange (ETDEWEB)

    Vandevelde, L

    2002-04-01

    The objectives, the programme, and the achievements of R and D at the Belgian Nuclear Research Centre SCK-CEN in the field of nuclear chemistry and analytical techniques are summarized. Major achievement in 2001 included the completion of a project on the measurement of critical radionuclides in reactor waste fluxes (the ARIANE project), the radiochemical characterisation of beryllium material originating from the second matrix of the BR2 reactor as well as to a the organisation of a workshop on the analysis of thorium and its isotopes in workplace materials.

  15. Advances in Phosphasilene Chemistry.

    Science.gov (United States)

    Nesterov, Vitaly; Breit, Nora C; Inoue, Shigeyoshi

    2017-09-07

    Heavier alkene analogues possess unique electronic properties and reactivity, encouraging multidisciplinary research groups to utilize them in the rational design of novel classes of compounds and materials. Phosphasilenes are heavier imine analogues, containing highly reactive Si=P double bonds. Recent achievements in this field are closely related to the progress in the chemistry of stable low-coordinate silicon compounds. In this Review, we have attempted to summarize in a comprehensive way the available data on the structures, syntheses, electronic and chemical properties of these compounds, with an emphasis on recent achievements. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Engineering Biosensors with Dual Programmable Dynamic Ranges.

    Science.gov (United States)

    Wei, Benmei; Zhang, Juntao; Ou, Xiaowen; Lou, Xiaoding; Xia, Fan; Vallée-Bélisle, Alexis

    2018-01-10

    Although extensively used in all fields of chemistry, molecular recognition still suffers from a significant limitation: host-guest binding displays a fixed, hyperbolic dose-response curve, which limits its usefulness in many applications. Here we take advantage of the high programmability of DNA chemistry and propose a universal strategy to engineer biorecognition-based sensors with dual programmable dynamic ranges. Using DNA aptamers as our model recognition element and electrochemistry as our readout signal, we first designed a dual signaling "signal-on" and "signal-off" adenosine triphosphate (ATP) sensor composed of a ferrocene-labeled ATP aptamer in complex to a complementary, electrode-bound, methylene-blue labeled DNA. Using this simple "dimeric" sensor, we show that we can easily (1) tune the dynamic range of this dual-signaling sensor through base mutations on the electrode-bound DNA, (2) extend the dynamic range of this sensor by 2 orders of magnitude by using a combination of electrode-bound strands with varying affinity for the aptamers, (3) create an ultrasensitive dual signaling sensor by employing a sequestration strategy in which a nonsignaling, high affinity "depletant" DNA aptamer is added to the sensor surface, and (4) engineer a sensor that simultaneously provides extended and ultrasensitive readouts. These strategies, applicable to a wide range of biosensors and chemical systems, should broaden the application of molecular recognition in various fields of chemistry.

  17. NUCLEAR CHEMISTRY ANNUAL REPORT 1970

    Energy Technology Data Exchange (ETDEWEB)

    Authors, Various

    1971-05-01

    Papers are presented for the following topics: (1) Nuclear Structure and Nuclear Properties - (a) Nuclear Spectroscopy and Radioactivity; (b) Nuclear Reactions and Scattering; (c) Nuclear Theory; and (d) Fission. (2) Chemical and Atomic Physics - (a) Atomic and Molecular Spectroscopy; and (b) Hyperfine Interactions. (3) Physical, Inorganic, and Analytical Chemistry - (a) X-Ray Crystallography; (b) Physical and Inorganic Chemistry; (c) Radiation Chemistry; and (d) Chemical Engineering. (4) Instrumentation and Systems Development.

  18. The physical basis of chemistry

    CERN Document Server

    Warren, Warren S

    2000-01-01

    If the text you're using for general chemistry seems to lack sufficient mathematics and physics in its presentation of classical mechanics, molecular structure, and statistics, this complementary science series title may be just what you're looking for. Written for the advanced lower-division undergraduate chemistry course, The Physical Basis of Chemistry, Second Edition, offers students an opportunity to understand and enrich the understanding of physical chemistry with some quantum mechanics, the Boltzmann distribution, and spectroscopy. Posed and answered are questions concerning eve

  19. Podcasts in the Chemistry Teaching

    Directory of Open Access Journals (Sweden)

    Bruno Silva Leite

    2016-12-01

    Full Text Available Information and Communication Technologies (ICT provide facilities in teaching through education. There are many new tools and methodologies that use ICT as a knowledge-building support, but that are not always related to pedagogical practice. The Podcast is an important technology that can be used in the classroom. Using this tool, it can make the most interactive chemistry class, fleeing the classroom routine. However, it is necessary to point out that the podcast is just one feature that should be incorporated into education and not a substitute. This paper describes the development of Chemistry Podcasts by teachers and chemistry students in three disciplines in 2015. This study took place over a one-year period in a public University, in Pernambuco, Brazil. In the discipline of "Computer applied to the teaching of chemistry" participated 21 Chemistry teachers. In the disciplines of "Information and Communication Technologies in the teaching of chemistry" and "Informatics, Chemistry and Education" was composed of 54 undergraduate students in chemistry. Twelve podcasts were elaborated by students and five by teachers in this paper we present only nine. The results showed the contribution of podcasts produced by teachers and students in teaching and learning process chemistry. DOI: http://dx.doi.org/10.17807/orbital.v0i0.898

  20. Green Chemistry for Chemical Synthesis

    National Research Council Canada - National Science Library

    Chao-Jun Li; Barry M. Trost

    2008-01-01

    Green chemistry for chemical synthesis addresses our future challenges in working with chemical processes and products by inventing novel reactions that can maximize the desired products and minimize...

  1. Information theory in analytical chemistry

    National Research Council Canada - National Science Library

    Eckschlager, Karel; Danzer, Klaus

    1994-01-01

    Contents: The aim of analytical chemistry - Basic concepts of information theory - Identification of components - Qualitative analysis - Quantitative analysis - Multicomponent analysis - Optimum analytical...

  2. Solid state chemistry an introduction

    CERN Document Server

    Smart, Lesley E

    2012-01-01

    ""Smart and Moore are engaging writers, providing clear explanations for concepts in solid-state chemistry from the atomic/molecular perspective. The fourth edition is a welcome addition to my bookshelves. … What I like most about Solid State Chemistry is that it gives simple clear descriptions for a large number of interesting materials and correspondingly clear explanations of their applications. Solid State Chemistry could be used for a solid state textbook at the third or fourth year undergraduate level, especially for chemistry programs. It is also a useful resource for beginning graduate

  3. Learning with and about Advertising in Chemistry Education with a Lesson Plan on Natural Cosmetics--A Case Study

    Science.gov (United States)

    Belova, Nadja; Eilks, Ingo

    2015-01-01

    This paper describes a case study on the chemistry behind natural cosmetics in five chemistry learning groups (grades 7-11, age range 13-17) in a German comprehensive school. The lesson plan intends to promote critical media literacy in the chemistry classroom and specifically emphasizes learning with and about advertising. The lessons of four…

  4. Complex Protostellar Chemistry

    Science.gov (United States)

    Nuth, Joseph A., III; Johnson, Natasha M.

    2012-01-01

    Two decades ago, our understanding of the chemistry in protostars was simple-matter either fell into the central star or was trapped in planetary-scale objects. Some minor chemical changes might occur as the dust and gas fell inward, but such effects were overwhelmed by the much larger scale processes that occurred even in bodies as small as asteroids. The chemistry that did occur in the nebula was relatively easy to model because the fall from the cold molecular cloud into the growing star was a one-way trip down a well-known temperature-pressure gradient; the only free variable was time. However, just over 10 years ago it was suggested that some material could be processed in the inner nebula, flow outward, and become incorporated into comets (1, 2). This outward flow was confirmed when the Stardust mission returned crystalline mineral fragments (3) from Comet Wild 2 that must have been processed close to the Sun before they were incorporated into the comet. In this week's Science Express, Ciesla and Sandford (4) demonstrate that even the outermost regions of the solar nebula can be a chemically active environment. Their finding could have consequences for the rest of the nebula.

  5. Imaging Sciences Workshop, Proceedings, November 15-16, 1995

    Energy Technology Data Exchange (ETDEWEB)

    Candy, J.V.

    1995-11-01

    Welcome to the Imaging Sciences Workshop sponsored by C.A.S.I.S., the Center for Advanced Signal & Image Sciences. Many programs at LLNL use advanced signal and image processing techniques, and the Center was established to encourage the exchange of ideas and to promote collaboration by individuals from these programs. This Workshop is an opportunity for LLNL personnel and invited speakers from other organizations not only to present new work, but, perhaps more importantly, to discuss problems in an informal and friendly setting. This year marks the opening of the CASIS Reference Library in Building 272, and we encourage all attendees to stop by for a look and to make use of it in the future. The Technical Program covers a wide variety of applications at LLNL including physical systems for collecting data and processing techniques for recovering and enhancing images. We hope that you enjoy the presentations, and we encourage you to participate in the discussions. Thanks for attending.

  6. Mussel Survey, Locks 12, 15, 16, 17, and 19, Mississippi.

    Science.gov (United States)

    1987-11-01

    nodulata Pimple Back (q. pustulosa) Maple Leaf C(0. guadrula) Floater (Anodonta grandis)T Paper Pond Shell ( Anodont -a imbecillus! .4 ~ Rock Pocketbook...Warty Back (Q. nodulata) Pimple Back (Q~. pustulosa) Maple Leaf (0. guadrula) Floater (Anodonta grandis)- Paper Pond Shell ( Anodont -a-i-mbecillus

  7. Chemistry in Context: Analysis of Thematic Chemistry Videos Available Online

    Science.gov (United States)

    Christensson, Camilla; Sjöström, Jesper

    2014-01-01

    United Nations declared 2011 to be the International Year of Chemistry. The Swedish Chemical Society chose twelve themes, one for each month, to highlight the connection of chemistry with everyday life. Examples of themes were fashion, climate change, love, sports, communication, health issues, and food. From the themes various context-based…

  8. 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,…

  9. Chemistry for Whom? Gender Awareness in Teaching and Learning Chemistry

    Science.gov (United States)

    Andersson, Kristina

    2017-01-01

    Marie Ståhl and Anita Hussénius have defined what discourses dominate national tests in chemistry for Grade 9 in Sweden by using feminist, critical didactic perspectives. This response seeks to expand the results in Ståhl and Hussénius's article "Chemistry inside an epistemological community box!--Discursive exclusions and inclusions in the…

  10. Experimental interstellar organic chemistry: Preliminary findings

    Science.gov (United States)

    Khare, B. N.; Sagan, C.

    1971-01-01

    In a simulation of interstellar organic chemistry in dense interstellar clouds or on grain surfaces, formaldehyde, water vapor, ammonia and ethane are deposited on a quartz cold finger and ultraviolet-irradiated in high vacuum at 77K. The HCHO photolytic pathway which produces an aldehyde radical and a superthermal hydrogen atom initiates solid phase chain reactions leading to a range of new compounds, including methanol, ethanol, acetaldehyde, acetonitrile, acetone, methyl formate, and possibly formic acid. Higher nitriles are anticipated. Genetic relations among these interstellar organic molecules (e.g., the Cannizzaro and Tischenko reactions) must exist. Some of them, rather than being synthesized from smaller molecules, may be degradation products of larger organic molecules, such as hexamethylene tetramine, which are candidate consitituents of the interstellar grains. The experiments reported here may also be relevant to cometary chemistry.

  11. Laser experiments for chemistry and physics

    CERN Document Server

    Compton, Robert N

    2016-01-01

    Lasers are employed throughout science and technology, in fundamental research, the remote sensing of atmospheric gases or pollutants, communications, medical diagnostics and therapies, and the manufacturing of microelectronic devices. Understanding the principles of their operation, which underlie all of these areas, is essential for a modern scientific education. This text introduces the characteristics and operation of lasers through laboratory experiments designed for the undergraduate curricula in chemistry and physics. Introductory chapters describe the properties of light, the history of laser invention, the atomic, molecular, and optical principles behind how lasers work, and the kinds of lasers available today. Other chapters include the basic theory of spectroscopy and computational chemistry used to interpret laser experiments. Experiments range from simple in-class demonstrations to more elaborate configurations for advanced students. Each chapter has historical and theoretical background, as well...

  12. Nuclear Chemistry and Chemistry of f-Elements in Chemistry Curriculum at Secondary Schools

    OpenAIRE

    Distler, Petr

    2016-01-01

    This master's degree thesis, called Nuclear Chemistry and Chemistry of f-Elements in Chemistry Curriculum at Secondary Schools, conducts a research of the most commonly used high school textbooks. Within the textbook research, topics such as atomic nucleus composition, radioactivity, and f-elements were studied in order to evaluate to what extent contemporary textbooks meet to the curriculum requirements. Based on the textbook research, the new teaching texts, materials, and teaching tasks in...

  13. 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.

  14. 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.

  15. From organic chemistry to fat and oil chemistry*

    Directory of Open Access Journals (Sweden)

    Deffense Etienne

    2009-01-01

    Full Text Available With his work on animal fat and identification of fatty acids, Chevreul was a pioneer in organic chemistry. As Chevreul, I had a passion for organic chemistry too. It was then, an honour and a pleasure to present in 2008 at EFL in Athens this presentation entitled “From organic chemistry to fat and oil chemistry” because my background in organic chemistry helped me all along my professional career to understand and implement new developments related to oil and fat technology and processing. Among the topics which I worked out, I highlighted more particularly the following subjects: the degumming chemistry of oil and fat; the improvement of physical refining; a new chemical analytical tool for the dry fractionation; new development in the dry fractionation

  16. Significant steps in the evolution of analytical chemistry--is the today's analytical chemistry only chemistry?

    Science.gov (United States)

    Karayannis, Miltiades I; Efstathiou, Constantinos E

    2012-12-15

    In this review the history of chemistry and specifically the history and the significant steps of the evolution of analytical chemistry are presented. In chronological time spans, covering the ancient world, the middle ages, the period of the 19th century, and the three evolutional periods, from the verge of the 19th century to contemporary times, it is given information for the progress of chemistry and analytical chemistry. During this period, analytical chemistry moved gradually from its pure empirical nature to more rational scientific activities, transforming itself to an autonomous branch of chemistry and a separate discipline. It is also shown that analytical chemistry moved gradually from the status of exclusive serving the chemical science, towards serving, the environment, health, law, almost all areas of science and technology, and the overall society. Some recommendations are also directed to analytical chemistry educators concerning the indispensable nature of knowledge of classical analytical chemistry and the associated laboratory exercises and to analysts, in general, why it is important to use the chemical knowledge to make measurements on problems of everyday life. Copyright © 2012 Elsevier B.V. All rights reserved.

  17. Tropospheric Halogen Chemistry

    Science.gov (United States)

    von Glasow, R.; Crutzen, P. J.

    2003-12-01

    Halogens are very reactive chemicals that are known to play an important role in anthropogenic stratospheric ozone depletion chemistry, first recognized by Molina and Rowland (1974). However, they also affect the chemistry of the troposphere. They are of special interest because they are involved in many reaction cycles that can affect the oxidation power of the atmosphere indirectly by influencing the main oxidants O3 and its photolysis product OH and directly, e.g., by reactions of the Cl radical with hydrocarbons (e.g., CH4).Already by the middle of the nineteenth century, Marchand (1852) reported the presence of bromine and iodine in rain and other natural waters. He also mentions the benefits of iodine in drinking water through the prevention of goitres and cretinism. In a prophetic monograph "Air and Rain: The Beginnings of a Chemical Climatology," Smith (1872) describes measurements of chloride in rain water, which he states to originate partly from the oceans by a process that he compares with the bursting of "soap bubbles" which produces "small vehicles" that transfer small spray droplets of seawater to the air. From deviations of the sulfate-to-chloride ratio in coastal rain compared to seawater, Smith concluded that chemical processes occur once the particles are airborne.For almost a century thereafter, however, atmospheric halogens received little attention. One exception was the work by Cauer (1939), who reported that iodine pollution has been significant in Western and Central Europe due to the inefficient burning of seaweed, causing mean gas phase atmospheric concentrations as high as or greater than 0.5 μg m-3. In his classical textbook Air Chemistry and Radioactivity, Junge (1963) devoted less than three pages to halogen gas phase chemistry, discussing chlorine and iodine. As reviewed by Eriksson (1959a, b), the main atmospheric source of halogens is sea salt, derived from the bursting of bubbles of air which are produced by ocean waves and other

  18. Dynamic imine chemistry.

    Science.gov (United States)

    Belowich, Matthew E; Stoddart, J Fraser

    2012-03-21

    Formation of an imine--from an amine and an aldehyde--is a reversible reaction which operates under thermodynamic control such that the formation of kinetically competitive intermediates are, in the fullness of time, replaced by the thermodynamically most stable product(s). For this fundamental reason, the imine bond has emerged as an extraordinarily diverse and useful one in the hands of synthetic chemists. Imine bond formation is one of a handful of reactions which define a discipline known as dynamic covalent chemistry (DCC), which is now employed widely in the construction of exotic molecules and extended structures on account of the inherent 'proof-reading' and 'error-checking' associated with these reversible reactions. While both supramolecular chemistry and DCC operate under the regime of reversibility, DCC has the added advantage of constructing robust molecules on account of the formation of covalent bonds rather than fragile supermolecules resulting from noncovalent bonding interactions. On the other hand, these products tend to require more time to form--sometimes days or even months--but their formation can often be catalysed. In this manner, highly symmetrical molecules and extended structures can be prepared from relatively simple precursors. When DCC is utilised in conjunction with template-directed protocols--which rely on the use of noncovalent bonding interactions between molecular building blocks in order to preorganise them into certain relative geometries as a prelude to the formation of covalent bonds under equilibrium control--an additional level of control of structure and topology arises which offers a disarmingly simple way of constructing mechanically-interlocked molecules, such as rotaxanes, catenanes, Borromean rings, and Solomon knots. This tutorial review focuses on the use of dynamic imine bonds in the construction of compounds and products formed with and without the aid of additional templates. While synthesis under thermodynamic

  19. Compressed Sensing for Chemistry

    Science.gov (United States)

    Sanders, Jacob Nathan

    Many chemical applications, from spectroscopy to quantum chemistry, involve measuring or computing a large amount of data, and then compressing this data to retain the most chemically-relevant information. In contrast, compressed sensing is an emergent technique that makes it possible to measure or compute an amount of data that is roughly proportional to its information content. In particular, compressed sensing enables the recovery of a sparse quantity of information from significantly undersampled data by solving an ℓ 1-optimization problem. This thesis represents the application of compressed sensing to problems in chemistry. The first half of this thesis is about spectroscopy. Compressed sensing is used to accelerate the computation of vibrational and electronic spectra from real-time time-dependent density functional theory simulations. Using compressed sensing as a drop-in replacement for the discrete Fourier transform, well-resolved frequency spectra are obtained at one-fifth the typical simulation time and computational cost. The technique is generalized to multiple dimensions and applied to two-dimensional absorption spectroscopy using experimental data collected on atomic rubidium vapor. Finally, a related technique known as super-resolution is applied to open quantum systems to obtain realistic models of a protein environment, in the form of atomistic spectral densities, at lower computational cost. The second half of this thesis deals with matrices in quantum chemistry. It presents a new use of compressed sensing for more efficient matrix recovery whenever the calculation of individual matrix elements is the computational bottleneck. The technique is applied to the computation of the second-derivative Hessian matrices in electronic structure calculations to obtain the vibrational modes and frequencies of molecules. When applied to anthracene, this technique results in a threefold speed-up, with greater speed-ups possible for larger molecules. The

  20. Gas Phase Sulfur, Chlorine and Potassium Chemistry in Biomass Combustion

    DEFF Research Database (Denmark)

    Løj, Lusi Hindiyarti

    2007-01-01

    Gas Phase Sulfur, Chlorine and Alkali Metal Chemistry in Biomass Combustion Concern about aerosols formation, deposits, corrosion, and gaseous emissions during biomass combustion, especially straw, continues to be a driving force for investigation on S, Cl, K-containing species under combustions...... the uncertainties. In the present work, the detailed kinetic model for gas phase sulfur, chlorine, alkali metal, and their interaction has been updated. The K/O/H/Cl chemistry, S chemistry, and their interaction can reasonably predict a range of experimental data. In general, understanding of the interaction...... conditions. These trace species contained in the biomass structure will be released to the gas phase during combustion and contribute to the problems generated during the process. The investigation during this PhD project is done to stepwise improve the understanding in the chemistry and reduce...

  1. News from Online: Green Chemistry

    Science.gov (United States)

    Uffelman, Erich S.

    2004-01-01

    Green chemistry closely relates to energy and environmental problems, and includes the promotion of environmental friendly products and systems within the framework of renewable resources. Various websites on green chemistry are reviewed, one of which lists the 12 commandments of this particular subject.

  2. Chemistry Teachers' Views of Creativity

    Science.gov (United States)

    Akkanat, Çigdem; Gökdere, Murat

    2015-01-01

    The purpose of this study was to determine chemistry teachers' views of creativity. In this study, phenomenology method, one of the qualitative research patterns, was used. The participants of this study were 13 chemistry teachers working in Amasya. A semi-structured interview form was used for data collection. By using NVivo 9 qualitative…

  3. How fast is ultrafast chemistry

    OpenAIRE

    Bagchi, Biman

    1995-01-01

    The field of ultrafast chemistry has seen a string of remarkable discoveries in the recent years. In this article we briefly discuss some of the problems solved recently. The understanding that has emerged from these studies has important consequences non only in chemistry but also in diverse biological processes.

  4. Modern Trends in Inorganic Chemistry

    Indian Academy of Sciences (India)

    Administrator

    The series of symposia on 'Modern Trends in Inorganic Chemistry' (MTIC), which began in 1985 at the Indian Association for Cultivation of Science, Calcutta has evolved into a forum for the Inorganic Chemistry fraternity of the country to meet every two years and discuss the current status and future projections of research in.

  5. Plasma chemistry and its applications

    Science.gov (United States)

    Hozumi, K.

    1980-01-01

    The relationship between discharge phenomena and plasma chemistry, as well as the equipment and mechanisms of plasma chemical reactions are described. Various areas in which plasma chemistry is applied are surveyed, such as: manufacturing of semiconductor integrated circuits; synthetic fibers; high polymer materials for medical uses; optical lenses; and membrane filters (reverse penetration films).

  6. Introducing Relativity into Quantum Chemistry

    Science.gov (United States)

    Li, Wai-Kee; Blinder, S. M.

    2011-01-01

    It is not often realized by chemists that the special theory of relativity is behind several aspects of quantum chemistry. The Schrdinger equation itself is based on relations between space-time and energy-momentum four vectors. Electron spin is, of course, the most obvious manifestation of relativity. The chemistry of some heavy elements is…

  7. Contextualising Nanotechnology in Chemistry Education

    Science.gov (United States)

    O'Connor, Christine; Hayden, Hugh

    2008-01-01

    In recent years nanotechnology has become part of the content of many undergraduate chemistry and physics degree courses. This paper deals with the role of contextualisation of nanotechnology in the delivery of the content, as nanotechnology is only now being slowly integrated into many chemistry degree courses in Ireland and elsewhere. An…

  8. New Thinking in School Chemistry.

    Science.gov (United States)

    Organisation for Economic Cooperation and Development, Paris (France).

    This report contains the text of addresses given at a seminar on the status and development of the teaching of secondary school chemistry held in 1960 by the Organization for European Economic Development (now the Organization for Economic Cooperation and Development). The speakers considered advances in theoretical chemistry since 1900, the…

  9. Rethinking Undergraduate Physical Chemistry Curricula

    Science.gov (United States)

    Miller, Stephen R.

    2016-01-01

    A summary of fundamental changes made to the undergraduate physical chemistry curriculum in the Chemistry Department at Gustavus Adolphus College (beginning in the 2013-2014 academic year) is presented. The yearlong sequence now consists of an introductory semester covering both quantum mechanics and thermodynamics/kinetics, followed by a second…

  10. Refresher Course in Experimental Chemistry

    Indian Academy of Sciences (India)

    Srimath

    diverse topics such as chemical kinetics, electrochemistry, spectrophotometry, polymer chemistry, advanced synthesis in inorganic and organic chemistry and molecular modelling. The focus of this. Course is to acquaint the participants with novel avenues of sensitizing the students at the undergraduate level about the ...

  11. Organic chemistry on Titan

    Science.gov (United States)

    Chang, S.; Scattergood, T.; Aronowitz, S.; Flores, J.

    1979-01-01

    Features taken from various models of Titan's atmosphere are combined in a working composite model that provides environmental constraints within which different pathways for organic chemical synthesis are determined. Experimental results and theoretical modeling suggest that the organic chemistry of the satellite is dominated by two processes: photochemistry and energetic particle bombardment. Photochemical reactions of CH4 in the upper atmosphere can account for the presence of C2 hydrocarbons. Reactions initiated at various levels of the atmosphere by cosmic rays, Saturn 'wind', and solar wind particle bombardment of a CH4-N2 atmospheric mixture can account for the UV-visible absorbing stratospheric haze, the reddish appearance of the satellite, and some of the C2 hydrocarbons. In the lower atmosphere photochemical processes will be important if surface temperatures are sufficiently high for gaseous NH3 to exist. It is concluded that the surface of Titan may contain ancient or recent organic matter (or both) produced in the atmosphere.

  12. Getting Hooked on Chemistry

    Science.gov (United States)

    Mason, Diana S.

    2002-04-01

    Other fun things in this issue include three Quote Boxes by Olney (3) that will allow your students to engage in deductive reasoning to solve the puzzles. Kelkar (4) presents a slightly more difficult but very clever mystery element game; it provides clues to element symbols that all fit into a single matrix. Ibanez's game (5) lists popular sayings or proverbs and the student's job is to match each with an analogous chemical phenomenon. As always, answers are provided. For the more sophisticated among us, there is Who Wants to Be a Chemist Extraordinaire? devised by Campbell and Muzyka (6), who describe their use of online chemistry game shows patterned on popular TV programs. Examples of the HTML files with sample questions are available through JCE Online. These are just some of the many suggestions that can be found in this issue of JCE. Try a few, you might like them!

  13. Introduction to structural chemistry

    CERN Document Server

    Batsanov, Stepan S

    2014-01-01

    A concise description of models and quantitative parameters in structural chemistry and their interrelations, with 280 tables and >3000 references giving the most up-to-date experimental data on energy characteristics of atoms, molecules and crystals (ionisation potentials, electron affinities, bond energies, heats of phase transitions, band and lattice energies), optical properties (refractive index, polarisability), spectroscopic characteristics and geometrical parameters (bond distances and angles, coordination numbers) of substances in gaseous, liquid and solid states, in glasses and melts, for various thermodynamic conditions. Systems of metallic, covalent, ionic and van der Waals radii, effective atomic charges and other empirical and semi-empirical models are critically revised. Special attention is given to new and growing areas: structural studies of solids under high pressures and van der Waals molecules in gases. The book is addressed to researchers, academics, postgraduates and advanced-course stu...

  14. Beryllium chemistry and processing

    CERN Document Server

    Walsh, Kenneth A

    2009-01-01

    This book introduces beryllium; its history, its chemical, mechanical, and physical properties including nuclear properties. The 29 chapters include the mineralogy of beryllium and the preferred global sources of ore bodies. The identification and specifics of the industrial metallurgical processes used to form oxide from the ore and then metal from the oxide are thoroughly described. The special features of beryllium chemistry are introduced, including analytical chemical practices. Beryllium compounds of industrial interest are identified and discussed. Alloying, casting, powder processing, forming, metal removal, joining and other manufacturing processes are covered. The effect of composition and process on the mechanical and physical properties of beryllium alloys assists the reader in material selection. The physical metallurgy chapter brings conformity between chemical and physical metallurgical processing of beryllium, metal, alloys, and compounds. The environmental degradation of beryllium and its all...

  15. Lessons for Introductory Chemistry

    Science.gov (United States)

    Martin, John S.; Blackburn, Edward V.

    2000-07-01

    These twelve lessons, and an introductory lesson, are tutorials in basic topics of introductory chemistry. They are suitable for school use, individual study, or distance learning. They are particularly valuable as review material for students in more advanced courses who may have been away from the subject for some time. They contain a great variety of problems and exercises driven by random-number generators, so that the same problem never repeats exactly. The lessons are, for the most part, Socratic dialogues in which the student is required to answer questions and perform simulated experiments in order to discover chemical principles. They are organized in an intuitive chapter and page structure. One may move readily around each lesson. There are many on-screen facilities such as help, data tables, and a calculator.

  16. Advances in analytical chemistry

    Science.gov (United States)

    Arendale, W. F.; Congo, Richard T.; Nielsen, Bruce J.

    1991-01-01

    Implementation of computer programs based on multivariate statistical algorithms makes possible obtaining reliable information from long data vectors that contain large amounts of extraneous information, for example, noise and/or analytes that we do not wish to control. Three examples are described. Each of these applications requires the use of techniques characteristic of modern analytical chemistry. The first example, using a quantitative or analytical model, describes the determination of the acid dissociation constant for 2,2'-pyridyl thiophene using archived data. The second example describes an investigation to determine the active biocidal species of iodine in aqueous solutions. The third example is taken from a research program directed toward advanced fiber-optic chemical sensors. The second and third examples require heuristic or empirical models.

  17. Reaxys Medicinal Chemistry

    OpenAIRE

    2015-01-01

    Представлены руководства по работе с базой данных по медицинской химии REAXYS MEDICINAL CHEMISTRY издательства Elsevier на английском и русском языках.

  18. Silane Discharge Ion Chemistry.

    Science.gov (United States)

    Chatham, Robert Hood, III

    We have studied silane dc, rf and dc proximity discharges, using mass spectroscopic measurements of the positive ions as a detailed diagnostic for the type of discharge used to produce hydrogenated amorphous silicon solar photovoltaic cells. The properties and quality of these films depends in a very complex way upon the interactions of the many reactive neutral and ion species in the discharge. We have developed qualitative models of the ion chemical processes in these discharges from our measurements. Knowledge of the ion-molecule and electron-molecule collision cross sections is important to any attempt at understanding silane discharge chemistry. Consequently, we have measured the electron impact ionization cross sections for silane and disilane, and for comparison purposes also for methane and ethane. In addition, we have measured the rate coefficients for charge exchange reactions of He('+), Ne('+), and Ar('+) with silane, disilane, methane, and ethane, as these are important to understanding discharges in inert gas-silane mixtures. We have developed a detailed quantitative model of the cathode sheath region of a silane dc discharge, by extending the best recent calculation of the electron motion in the sheath to a self-consistent form which includes the ion motion. This model is used with comparison of silane dc discharge data to diagnose the ion chemistry occurring in the sheath region of silane dc discharge. The understanding of the discharge ion chemical processes that we have gained in this study represent an important step toward understanding the chemical and physical processes leading to film growth.

  19. Handbook of relativistic quantum chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Wenjian (ed.) [Peking Univ., Beijing (China). Center for Computational Science and Engineering

    2017-03-01

    This handbook focuses on the foundations of relativistic quantum mechanics and addresses a number of fundamental issues never covered before in a book. For instance: How can many-body theory be combined with quantum electrodynamics? How can quantum electrodynamics be interfaced with relativistic quantum chemistry? What is the most appropriate relativistic many-electron Hamiltonian? How can we achieve relativistic explicit correlation? How can we formulate relativistic properties? - just to name a few. Since relativistic quantum chemistry is an integral component of computational chemistry, this handbook also supplements the ''Handbook of Computational Chemistry''. Generally speaking, it aims to establish the 'big picture' of relativistic molecular quantum mechanics as the union of quantum electrodynamics and relativistic quantum chemistry. Accordingly, it provides an accessible introduction for readers new to the field, presents advanced methodologies for experts, and discusses possible future perspectives, helping readers understand when/how to apply/develop the methodologies.

  20. Selective host molecules obtained by dynamic adaptive chemistry.

    Science.gov (United States)

    Matache, Mihaela; Bogdan, Elena; Hădade, Niculina D

    2014-02-17

    Up till 20 years ago, in order to endow molecules with function there were two mainstream lines of thought. One was to rationally design the positioning of chemical functionalities within candidate molecules, followed by an iterative synthesis-optimization process. The second was the use of a "brutal force" approach of combinatorial chemistry coupled with advanced screening for function. Although both methods provided important results, "rational design" often resulted in time-consuming efforts of modeling and synthesis only to find that the candidate molecule was not performing the designed job. "Combinatorial chemistry" suffered from a fundamental limitation related to the focusing of the libraries employed, often using lead compounds that limit its scope. Dynamic constitutional chemistry has developed as a combination of the two approaches above. Through the rational use of reversible chemical bonds together with a large plethora of precursor libraries, one is now able to build functional structures, ranging from quite simple molecules up to large polymeric structures. Thus, by introduction of the dynamic component within the molecular recognition processes, a new perspective of deciphering the world of the molecular events has aroused together with a new field of chemistry. Since its birth dynamic constitutional chemistry has continuously gained attention, in particular due to its ability to easily create from scratch outstanding molecular structures as well as the addition of adaptive features. The fundamental concepts defining the dynamic constitutional chemistry have been continuously extended to currently place it at the intersection between the supramolecular chemistry and newly defined adaptive chemistry, a pivotal feature towards evolutive chemistry. Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Chemistry of Art and Color Sudoku Puzzles

    Science.gov (United States)

    Welsh, Michael J.

    2007-01-01

    Sudoku puzzle format was used to teach light science and chemistry terms to students of Chemistry of Art and Color. The puzzles were used to motivate and encourage students to learn chemistry in an easier and in friendly fashion.

  2. Chemistry Concepts and Vocabulary from Root Words

    Indian Academy of Sciences (India)

    /fulltext/reso/011/07/0080-0098. Keywords. Introductory chemistry; interdisciplinary; vocabulary; language of chemistry; curriculum. Author Affiliations. Nittala S Sarma1. School of Chemistry, Andhra University, Visakhapatnam 530 003, India ...

  3. Chemistry Perfumes Your Daily Life

    Science.gov (United States)

    Fortineau, Anne-Dominique

    2004-01-01

    The use of perfumes can be tracked back to many early civilizations. Historically, perfumes were composed exclusively of natural ingredients, mainly essential oils, and were reserved for the wealthiest people. The use of synthetic ingredients marked the beginning of modern perfumery at the end of the 19th century. Nowadays, perfumes are available to everyone and are present in a wide range of consumer goods. The methods used to extract perfume ingredients from their natural sources have changed over time as technology has advanced. Depending on the material, expression, distillation, and solvent extraction are the main techniques used to extract the odorant components from a natural source. Synthetic organic chemistry has provided perfumers with novel ingredients that are cheaper and more stable than many natural materials over the years. Today, more than 3000 fragrance ingredients are estimated to be available to perfumers to create a harmonious composition of head (for example, citrusy), heart (for example, fruity floral) and base notes (for example, musky). Future developments and uses of perfume are endless and as Ernest Beaux, the perfumer who created Chanel N85, once said, "In perfumery the future lies primarily in the hands of the chemists." Featured on the Cover See Featured Molecules .

  4. Chemistry for whom? Gender awareness in teaching and learning chemistry

    Science.gov (United States)

    Andersson, Kristina

    2017-06-01

    Marie Ståhl and Anita Hussénius have defined what discourses dominate national tests in chemistry for Grade 9 in Sweden by using feminist, critical didactic perspectives. This response seeks to expand the results in Ståhl and Hussénius's article Chemistry inside an epistemological community box!— Discursive exclusions and inclusions in the Swedish national tests in chemistry, by using different facets of gender awareness. The first facet—Gender awareness in relations to the test designers' own conceptions—highlighted how the gender order where women are subordinated men becomes visible in the national tests as a consequence of the test designers internalized conceptions. The second facet—Gender awareness in relation to chemistry—discussed the hierarchy between discourses within chemistry. The third facet—Gender awareness in relation to students—problematized chemistry in relation to the students' identity formation. In summary, I suggest that the different discourses can open up new ways to interpret chemistry and perhaps dismantle the hegemonic chemistry discourse.

  5. Aqueous chemistry of chlorine: chemistry, analysis, and environmental fate of reactive oxidant species

    Energy Technology Data Exchange (ETDEWEB)

    Jolley, R.L.; Carpenter, J.H.

    1982-01-01

    This report reviews (1) the chemistry of chlorine relative to its reactions in fresh, estuarine, and marine waters and the formation of reactive oxidant species; (2) the current status of chemical analysis of reactive chlorine species and chlorine-produced oxidant species relative to analysis of low concentrations (microgram-per-liter range) and determination of accuracy and precision of methods; and (3) the environmental fate of chlorine and chlorine-produced oxidant species.

  6. Is fossil cycle chemistry the Cinderella of power plant chemistry?

    Energy Technology Data Exchange (ETDEWEB)

    Bursik, L. [BHT GmbH, Kusterdingen-Wankheim (Germany); Bursik, A. [PowerPlant Chemistry GmbH, Neulussheim (Germany)

    2008-01-15

    A survey of the topics addressed at three major European power plant chemistry conferences has revealed that fossil cycle chemistry, like the neglected stepsister Cinderella, is not getting the attention it deserves. Boiler tube failures are the leading cause of forced outages in the conventional fossil plant utility industry, and heat recovery steam generator tube failures are the major cause of damage in the multiple-pressure combined-cycle plants. While other topics are surely important, more honest and open discussion of chemistry-related problems in fossil cycles is imperative to achieving operational benefits like higher reliability, availability, and efficiency. (orig.)

  7. 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

  8. Dynamics of forest soil chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Alveteg, M.

    1998-11-01

    Acidification caused by emissions of nitrogen and sulphur and associated adverse effects on forest ecosystems has been an issue on the political agenda for decades. Temporal aspects of soil acidification and/or recovery can be investigated using the soil chemistry model SAFE, a dynamic version of the steady-state model PROFILE used in critical loads assessment on the national level, e.g. for Sweden. In this thesis, possibilities to replace the use of apparent gibbsite solubility coefficients with a more mechanistic Al sub-model are investigated and a reconstruction model, MAKEDEP, is presented which makes hindcasts and forecasts of atmospheric deposition and nutrient uptake and cycling. A regional application of SAFE/MAKEDEP based on 622 sites in Switzerland is also presented. It is concluded that the quantitative information on pools and fluxes of Al in forest ecosystems is very limited and that there currently exists no mechanistic alternative in modelling soil solution Al. MAKEDEP is a valuable and operational tool for deriving input to dynamic soil chemistry models such as SMART, MAGIC and SAFE. For multi-layer models, e.g. the SAFE model, including nutrient cycling in MAKEDEP is shown to be important. The strength of the regional assessment strategy presented in this thesis lies in its transparency and modularity. All sub-modules, including models, transfer functions, assumptions in the data acquisition strategy, etc., can be checked and replaced individually. As the presented assessment strategy is based on knowledge and data from a wide range of scientists and fields it is of vital importance that the research community challenge the assumptions made. The many measurable intermediate results produced by the included models will hopefully encourage scientists to challenge the models through additional measurements at the calculation sites. It is concluded that current reduction plans are not sufficient for all forest ecosystems in Switzerland to recover from

  9. Allicin: Chemistry and Biological Properties

    Directory of Open Access Journals (Sweden)

    Jan Borlinghaus

    2014-08-01

    Full Text Available Allicin (diallylthiosulfinate is a defence molecule from garlic (Allium sativum L. with a broad range of biological activities. Allicin is produced upon tissue damage from the non-proteinogenic amino acid alliin (S-allylcysteine sulfoxide in a reaction that is catalyzed by the enzyme alliinase. Current understanding of the allicin biosynthetic pathway will be presented in this review. Being a thiosulfinate, allicin is a reactive sulfur species (RSS and undergoes a redox-reaction with thiol groups in glutathione and proteins that is thought to be essential for its biological activity. Allicin is physiologically active in microbial, plant and mammalian cells. In a dose-dependent manner allicin can inhibit the proliferation of both bacteria and fungi or kill cells outright, including antibiotic-resistant strains like methicillin-resistant Staphylococcus aureus (MRSA. Furthermore, in mammalian cell lines, including cancer cells, allicin induces cell-death and inhibits cell proliferation. In plants allicin inhibits seed germination and attenuates root-development. The majority of allicin’s effects are believed to be mediated via redox-dependent mechanisms. In sub-lethal concentrations, allicin has a variety of health-promoting properties, for example cholesterol- and blood pressure-lowering effects that are advantageous for the cardio-vascular system. Clearly, allicin has wide-ranging and interesting applications in medicine and (green agriculture, hence the detailed discussion of its enormous potential in this review. Taken together, allicin is a fascinating biologically active compound whose properties are a direct consequence of the molecule’s chemistry.

  10. Chemistry of Planetary Atmospheres: Insights and Prospects

    Science.gov (United States)

    Yung, Yuk

    2015-11-01

    Using observations from the Mariners, Pioneers, Vikings, Voyagers, Pioneer Venus, Galileo, Venus Express, Curiosity, Cassini, New Horizons, and numerous observatories both in orbit of Earth and on the ground, I will give a survey of the major chemical processes that control the composition of planetary atmospheres. For the first time since the beginning of the space age, we understand the chemistry of planetary atmospheres ranging from the primitive atmospheres of the giant planets to the highly evolved atmospheres of terrestrial planets and small bodies. Our understanding can be distilled into three important ideas: (1) The stability of planetary atmospheres against escape of their constituents to space, (2) the role of equilibrium chemistry in determining the partitioning of chemical species, and (3) the role of disequilibrium chemistry, which produces drastic departures from equilibrium chemistry. To these three ideas we must also add a fourth: the role of biochemistry at Earth's surface, which makes its atmospheric chemistry unique in the cosmochemical environment. Only in the Earth's atmosphere do strong reducing and oxidizing species coexist to such a degree. For example, nitrogen species in the Earth's atmosphere span eight oxidation states from ammonia to nitric acid. Much of the Earth's atmospheric chemistry consists of reactions initiated by the degradation of biologically produced molecules. Life uses solar energy to drive chemical reactions that would otherwise not occur; it represents a kind of photochemistry that is special to Earth, at least within the Solar System. It remains to be seen how many worlds like Earth there are beyond the Solar System, especially as we are now exploring the exoplanets using Kepler, TESS, HST, Spitzer, soon to be launched missions such as JWST and WFIRST, and ground-based telescopes. The atmospheres of the Solar System provide a benchmark for studying exoplanets, which in turn serve to test and extend our current

  11. Low temperature nitrogen chemistry. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Glarborg, P.; Dam-Johansen, K.; Kristensen, P.G.; Alzueta, M.; Roejel, H.

    1997-04-01

    The results of a two tasks program on Natural Gas Reburning are reported. The work involved an experimental and theoretical study of the reburning and hybrid reburning/SNCR chemistry in the 1000-1500 K range. The interactions between hydrocarbon and nitrogen chemistry under fuel-rich conditions were investigated in order to assess the NO{sub x} reduction potential of low temperature reburning. The effect of reburn fuel(carbon monoxide, methane, acetylene, ethylene, ethane, and methane/ethane mixture), temperature, stoichiometry, reactant dilution, reaction time, and inlet NO level were studied. The results indicate a significant NO reduction potential even below 1400 K, but extrapolation to practical conditions are complicated by inadequate knowledge of the detailed chemistry as well as of the effect of mixing. The possibilities of enhancing the conversion to N{sub 2} instead of NO by adding selective reducing agents (hybrid reburning/SNCR) were evaluated. Our results indicate little synergistic effect between reburn and SNCR. The most simple configuration, where the selective reducing agent is injected together with the burnout air, is not expected to be effective, unless the N-agent is injected in form of an aqueous solution. A chemical kinetic model for reburning and reburn/SNCR is listed and can be obtained by e-mail from pgl(commerical at)kt.dtu.dk.(au) 145 refs.

  12. Bioconjugation in pharmaceutical chemistry.

    Science.gov (United States)

    Veronese, F M; Morpurgo, M

    1999-08-30

    Polymer conjugation is of increasing interest in pharmaceutical chemistry for delivering drugs of simple structure or complex compounds such peptides, enzymes and oligonucleotides. For long time drugs, mainly with antitumoral activity, have been coupled to natural or synthetic polymers with the purpose of increasing their blood permanence time, taking advantage of the increased mass that reduces kidney ultrafiltration. However only recently complex constructs were devised that exploit the 'enhanced permeability and retention' (EPR) effect for an efficient tumor targeting, the high molecular weight for adsorption or receptor mediated endocytosis and finally a lysosomotropic targeting, taking advantage of acid labile bonds or cathepsin susceptible polypeptide spacers between polymer and drug. New original, very active conjugates of this type, as those based on poly(hydroxyacrylate) polymers, are already in advanced state of development. Labile oligonucleotides, including antisense drugs, were also successfully coupled to polymers in view of an increased cell penetration and stabilization towards nucleases. However, the most active research activity resides in the field of polypeptides and proteins delivery, mainly for the two following reasons: first of all because a great number of therapeutically interesting compounds are now being produced by genetic engineering in large quantity and, secondly, because these products are difficult to administer to patients for several inherent drawbacks. Proteins are in fact easily digested by many endo- and exo-peptidases present in blood or in other body districts; most of them are immunogenic to some extent and, finally, they are rapidly excreted by kidney ultrafiltration. Covalent polymer conjugation at protein surface was demonstrated to reduce or eliminate these problems, since the bound polymer behaves like a shield hindering the approach of proteolytic enzymes, antibodies, or antigen processing cell. Furthermore, the

  13. Alcohol combustion chemistry

    KAUST Repository

    Sarathy, Mani

    2014-10-01

    Alternative transportation fuels, preferably from renewable sources, include alcohols with up to five or even more carbon atoms. They are considered promising because they can be derived from biological matter via established and new processes. In addition, many of their physical-chemical properties are compatible with the requirements of modern engines, which make them attractive either as replacements for fossil fuels or as fuel additives. Indeed, alcohol fuels have been used since the early years of automobile production, particularly in Brazil, where ethanol has a long history of use as an automobile fuel. Recently, increasing attention has been paid to the use of non-petroleum-based fuels made from biological sources, including alcohols (predominantly ethanol), as important liquid biofuels. Today, the ethanol fuel that is offered in the market is mainly made from sugar cane or corn. Its production as a first-generation biofuel, especially in North America, has been associated with publicly discussed drawbacks, such as reduction in the food supply, need for fertilization, extensive water usage, and other ecological concerns. More environmentally friendly processes are being considered to produce alcohols from inedible plants or plant parts on wasteland. While biofuel production and its use (especially ethanol and biodiesel) in internal combustion engines have been the focus of several recent reviews, a dedicated overview and summary of research on alcohol combustion chemistry is still lacking. Besides ethanol, many linear and branched members of the alcohol family, from methanol to hexanols, have been studied, with a particular emphasis on butanols. These fuels and their combustion properties, including their ignition, flame propagation, and extinction characteristics, their pyrolysis and oxidation reactions, and their potential to produce pollutant emissions have been intensively investigated in dedicated experiments on the laboratory and the engine scale

  14. EFSA Panel on food contact materials, enzymes, flavourings and processing aids (CEF); Scientific Opinion on Flavouring Group Evaluation 23, Revision 2 (FGE.23Rev2): Aliphatic, alicyclic and aromatic ethers including anisole derivatives from chemical groups 15, 16, 22, 26 and 30

    DEFF Research Database (Denmark)

    Larsen, John Christian; Nørby, Karin Kristiane; Beltoft, Vibe Meister

    The European Food Safety Authority (EFSA) asked the Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids (the Panel) to provide scientific advice to the Commission on the implications for human health of chemically defined flavouring substances used in or on foodstuffs...... in the Member States. In particular, the Panel was requested to evaluate 19 flavouring substances in the Flavouring Group Evaluation 23, Revision 2 (FGE.23Rev2), using the Procedure as referred to in the Commission Regulation (EC) No 1565/2000. These 19 flavouring substances belong to chemical groups 15, 16, 22......-no: 03.022] Industry has informed that it occurs as a mixture of E- & Z-isomers, however, the composition of the mixture has to be specified. Two of the flavouring substances are classified into structural class I, seven are classified into structural class II and 10 are classified into structural class...

  15. Alfa Chemistry Released New Application in Medicinal Chemistry.pdf

    OpenAIRE

    Mica, Chloe

    2016-01-01

    Study on lure conditions of food attracts for stored-grain pests could afford theoretics base for exploitation food attracts, but also enhances trap effects of insect pheromone by associated with food attracts and coh chemistry.

  16. The radiation chemistry of macromolecules

    CERN Document Server

    1973-01-01

    The Radiation Chemistry of Macromolecules, Volume II is a collection of papers that discusses radiation chemistry of specific systems. Part 1 deals with radiation chemistry of substituted vinyl polymers, particularly polypropylene (PP) as its structure is intermediate between polyethylene and polyisobutylene. This part also discusses polypropylene oxide (PPOx) for it can be prepared in the atactic, isotactic, and optically active forms. One paper focuses on the fundamental chemical processes and the changes in physical properties that give rise to many different applications of polystyrene. An

  17. Smart Cities Will Need Chemistry

    Directory of Open Access Journals (Sweden)

    Alexandru WOINAROSCHY

    2016-06-01

    Full Text Available A smart city is a sustainable and efficient urban centre that provides a high quality of life to its inhabitants through optimal management of its resources. Chemical industry has a key role to play in the sustainable evolution of the smart cities. Additionally, chemistry is at the heart of all modern industries, including electronics, information technology, biotechnology and nano-technology. Chemistry can make the smart cities project more sustainable, more energy efficient and more cost effective. There are six broad critical elements of any smart city: water management systems; infrastructure; transportation; energy; waste management and raw materials consumption. In all these elements chemistry and chemical engineering are deeply involved.

  18. Catalysis and sustainable (green) chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Centi, Gabriele; Perathoner, Siglinda [Dipartimento di Chimica Industriale ed Ingegneria dei Materiali, University of Messina, Salita Sperone 31, 98166 Messina (Italy)

    2003-01-15

    Catalysis is a key technology to achieve the objectives of sustainable (green) chemistry. After introducing the concepts of sustainable (green) chemistry and a brief assessment of new sustainable chemical technologies, the relationship between catalysis and sustainable (green) chemistry is discussed and illustrated via an analysis of some selected and relevant examples. Emphasis is also given to the concept of catalytic technologies for scaling-down chemical processes, in order to develop sustainable production processes which reduce the impact on the environment to an acceptable level that allows self-depuration processes of the living environment.

  19. Advances in electron transfer chemistry

    CERN Document Server

    Mariano, Patrick S

    1993-01-01

    Advances in Electron Transfer Chemistry, Volume 3 presents studies that discuss findings in the various aspects of electron chemistry. The book is comprised of four chapters; each chapter reviews a work that tackles an issue in electron transfer chemistry. Chapter 1 discusses the photoinduced electron transfer in flexible biaryl donor-acceptor molecules. Chapter 2 tackles light-induced electron transfer in inorganic systems in homogeneous and heterogeneous phases. The book also covers internal geometry relaxation effects on electron transfer rates of amino-centered systems. The sequential elec

  20. Applications, benefits and challenges of flow chemistry

    DEFF Research Database (Denmark)

    Mitic, Aleksandar; Heintz, Søren; Ringborg, Rolf Hoffmeyer

    2013-01-01

    Organic synthesis (incorporating both chemo-catalysis and biocatalysis) is essential for the production of a wide range of small-molecule pharmaceuticals. However, traditional production processes are mainly based on batch and semi-batch operating modes, which have disadvantages from an economic......, environmental and manufacturing perspective. A potential solution to resolve these issues is to use flow chemistry in such processes, preferably with applications of micro-and mini-sized equipment. In addition, Process Analytical Technology (PAT) may be implemented in a very efficient way in such equipment due...

  1. Range management visual impacts

    Science.gov (United States)

    Bruce R. Brown; David Kissel

    1979-01-01

    Historical overgrazing of western public rangelands has resulted in the passage of the Public Rangeland Improvement Act of 1978. The main purpose of this Act is to improve unsatisfactory range conditions. A contributing factor to unfavorable range conditions is adverse visual impacts. These visual impacts can be identified in three categories of range management: range...

  2. Atmospheric and aerosol chemistry

    Energy Technology Data Exchange (ETDEWEB)

    McNeill, V. Faye [Columbia Univ., New York, NY (United States). Dept. of Chemical Engineering; Ariya, Parisa A. (ed.) [McGill Univ. Montreal, QC (Canada). Dept. of Chemistry; McGill Univ. Montreal, QC (Canada). Dept. of Atmospheric and Oceanic Sciences

    2014-09-01

    This series presents critical reviews of the present position and future trends in modern chemical research. Short and concise reports on chemistry, each written by the world renowned experts. Still valid and useful after 5 or 10 years. More information as well as the electronic version of the whole content available at: springerlink.com. Christian George, Barbara D'Anna, Hartmut Herrmann, Christian Weller, Veronica Vaida, D. J. Donaldson, Thorsten Bartels-Rausch, Markus Ammann Emerging Areas in Atmospheric Photochemistry. Lisa Whalley, Daniel Stone, Dwayne Heard New Insights into the Tropospheric Oxidation of Isoprene: Combining Field Measurements, Laboratory Studies, Chemical Modelling and Quantum Theory. Neil M. Donahue, Allen L. Robinson, Erica R. Trump, Ilona Riipinen, Jesse H. Kroll Volatility and Aging of Atmospheric Organic Aerosol. P. A. Ariya, G. Kos, R. Mortazavi, E. D. Hudson, V. Kanthasamy, N. Eltouny, J. Sun, C. Wilde Bio-Organic Materials in the Atmosphere and Snow: Measurement and Characterization V. Faye McNeill, Neha Sareen, Allison N. Schwier Surface-Active Organics in Atmospheric Aerosols.

  3. Mars aqueous chemistry experiment

    Science.gov (United States)

    Clark, Benton C.; Mason, Larry W.

    1994-01-01

    Mars Aqueous Chemistry Experiment (MACE) is designed to conduct a variety of measurements on regolith samples, encompassing mineral phase analyses, chemical interactions with H2O, and physical properties determinations. From these data, much can be learned or inferred regarding the past weathering environment, the contemporaneous soil micro-environments, and the general chemical and physical state of the Martian regolith. By analyzing both soil and duricrust samples, the nature of the latter may become more apparent. Sites may be characterized for comparative purposes and criteria could be set for selection of high priority materials on future sample return missions. The second year of the MACE project has shown significant progress in two major areas. MACE Instrument concept definition is a baseline design that has been generated for the complete MACE instrument, including definition of analysis modes, mass estimates and thermal model. The design includes multiple reagent reservoirs, 10 discrete analysis cells, sample manipulation capability, and thermal control. The MACE Measurement subsystems development progress is reported regarding measurement capabilities for aqueous ion sensing, evolved gas sensing, solution conductivity measurement, reagent addition (titration) capabilities, and optical sensing of suspended particles.

  4. Analytical Chemistry Laboratory progress report for FY 1985

    Energy Technology Data Exchange (ETDEWEB)

    Green, D.W.; Heinrich, R.R.; Jensen, K.J.

    1985-12-01

    The Analytical Chemistry Laboratory is a full-cost-recovery service center, with the primary mission of providing a broad range of technical support services to the scientific and engineering programs at ANL. In addition, ACL conducts a research program in analytical chemistry, works on instrumental and methods development, and provides analytical services for governmental, educational, and industrial organizations. The ACL handles a wide range of analytical problems, from routine standard analyses to unique problems that require significant development of methods and techniques. The purpose of this report is to summarize the technical and administrative activities of the Analytical Chemistry Laboratory (ACL) at Argonne National Laboratory (ANL) for Fiscal Year 1985 (October 1984 through September 1985). This is the second annual report for the ACL. 4 figs., 1 tab.

  5. NWCA 2011 Soil Chemistry - Data

    Data.gov (United States)

    U.S. Environmental Protection Agency — NWCA 2011 Soil Chemistry Data. This dataset is associated with the following publication: Nahlik, A., and M.S. Fennessy. Carbon storage in US wetlands. Nature...

  6. Promoting sustainability through green chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Kirchhoff, Mary M. [American Chemical Society, 1155 Sixteenth Street, NW, Washington, DC 20036 (United States)

    2005-06-15

    Green chemistry is an important tool in achieving sustainability. The implementation of green chemistry, the design of chemical products and processes that reduce or eliminate the use and generation of hazardous substances, is essential if the expanding global population is to enjoy an increased standard of living without having a negative impact on the health of the planet. Cleaner technologies will allow the chemical enterprise to provide society with the goods and services on which it depends in an environmentally responsible manner. Green chemistry provides solutions to such global challenges as climate change, sustainable agriculture, energy, toxics in the environment, and the depletion of natural resources. A collaborative effort by industry, academia, and government is needed to promote the adoption of the green chemistry technologies necessary to achieve a sustainable society.

  7. Phosphorus chemistry in everyday living

    National Research Council Canada - National Science Library

    Toy, Arthur D. F

    1976-01-01

    The author has drawn on his 35 years of experience as a research scientist in phosphorus chemistry to produce a book that is not only readable to the non-chemist but sophisticated enough to interest...

  8. Plants and Medicinal Chemistry--2

    Science.gov (United States)

    Bailey, D.

    1977-01-01

    Second of a two part article on the influence of plants on medicinal chemistry. This part considers how drugs work, the attempts to develop anaesthetics safer than cocaine, and useful poisons. (Author/SL)

  9. Sexism in the Chemistry Curriculum

    Science.gov (United States)

    Arnold, Lois

    1977-01-01

    Pinpoints the kinds of problems that must be dealt with in attempting to eliminate sexism from educational materials in chemistry at the secondary level--problems of language, illustrations, and content. (Author/RK)

  10. The Chemistry of a Mini

    Science.gov (United States)

    Jones, C. E.

    1972-01-01

    Describes various parts of a mini car and their chemical composition. Useful information is included for science teachers to relate basic chemistry concepts and techniques with their application in automobile industry. (PS)

  11. Chemistry Education: Experiments Worth Running

    Science.gov (United States)

    Kirchhoff, Mary M.

    2007-01-01

    The Education system has decided to introduce various new experiments and a digital system for imparting chemistry education to children in schools. The new programs are expected to prepare graduate students completely for their professional lives beyond the graduate school.

  12. Chemistry of Cigarette Burning Processes

    Directory of Open Access Journals (Sweden)

    Chen P

    2014-12-01

    Full Text Available Cigarette-burning and the smoke-formation processes and smoke composition are important topics for understanding cigarette performance. This paper proposes the molecular formulas representing the active components of bright, burley, and Oriental tobaccos and a basic chemistry model of the cigarette burning processes. Previous knowledge of the cigarette burning processes and smoke formation helped to establish parameters in deriving the basic chemistry equations. The proposed chemistry provides a brief view of the mechanisms of the cigarette burning during puffing and interpuff smoldering, and can be used to interpret and predict the smoke composition for cigarettes made from bright, burley, and Oriental tobaccos. Based on the proposed chemistry, the effect of ventilation on smoke component deliveries is discussed and the reaction heat of the puffing process is estimated.

  13. Organometallic chemistry of metal surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Muetterties, E.L.

    1981-06-01

    The organometallic chemistry of metal surfaces is defined as a function of surface crystallography and of surface composition for a set of cyclic hydrocarbons that include benzene, toluene, cyclohexadienes, cyclohexene, cyclohexane, cyclooctatetraene, cyclooctadienes, cyclooctadiene, cycloheptatriene and cyclobutane. 12 figures.

  14. Constitutive Pluralism of Chemistry: Thought Planning, Curriculum, Epistemological and Didactic Orientations

    Science.gov (United States)

    Ribeiro, Marcos Antonio Pinto; Pereira, Duarte Costa

    2013-01-01

    Maybe the most difficult aspect of thinking about chemistry arises from the fact that chemistry isn't an homogeneous subject. As a central science, it draws on a range of philosophical perspectives which in turn can result in different cognitive, learning and teaching styles in chemical education. This idea, apparently non-controversial, needs to…

  15. Smart Cities Will Need Chemistry

    OpenAIRE

    Alexandru WOINAROSCHY

    2016-01-01

    A smart city is a sustainable and efficient urban centre that provides a high quality of life to its inhabitants through optimal management of its resources. Chemical industry has a key role to play in the sustainable evolution of the smart cities. Additionally, chemistry is at the heart of all modern industries, including electronics, information technology, biotechnology and nano-technology. Chemistry can make the smart cities project more sustainable, more energy efficient and more cos...

  16. Overview of PWR chemistry options

    Energy Technology Data Exchange (ETDEWEB)

    Nordmann, F.; Stutzmann, A.; Bretelle, J.L. [Electricite de France, Central Labs. (France)

    2002-07-01

    EDF Central Laboratories, in charge of engineering in chemistry, of defining the chemistry specifications and studying the operation feedback and improvement for 58 PWR units, have the opportunity to evaluate many options of operation developed and applied all around the world. Thanks to these international relationships and to the benefit of a large feedback from many units, some general evaluation of the various options is discussed in this paper. (authors)

  17. DNA-encoded chemistry: enabling the deeper sampling of chemical space.

    Science.gov (United States)

    Goodnow, Robert A; Dumelin, Christoph E; Keefe, Anthony D

    2017-02-01

    DNA-encoded chemical library technologies are increasingly being adopted in drug discovery for hit and lead generation. DNA-encoded chemistry enables the exploration of chemical spaces four to five orders of magnitude more deeply than is achievable by traditional high-throughput screening methods. Operation of this technology requires developing a range of capabilities including aqueous synthetic chemistry, building block acquisition, oligonucleotide conjugation, large-scale molecular biological transformations, selection methodologies, PCR, sequencing, sequence data analysis and the analysis of large chemistry spaces. This Review provides an overview of the development and applications of DNA-encoded chemistry, highlighting the challenges and future directions for the use of this technology.

  18. Creating a Context for Chemistry

    Science.gov (United States)

    Truman Schwartz, A.

    Until relatively recently, the teaching of chemistry at the college and university level in the United States has been quite traditional and oriented primarily toward the preparation of chemists. Students not concentrating in the sciences have often been poorly served by existing courses. Chemistry in Context: Applying Chemistry to Society, a textbook for nonscience majors developed under the sponsorship of the American Chemical Society, is an effort to address the needs and interests of this audience. The book introduces the phenomena and principles of chemistry within the context of socially significant issues such as global warming, ozone depletion, alternate energy sources, nutrition, and genetic engineering. The chemistry is presented as needed to inform an understanding of the central topics, and the text features student-centered activities designed to promote critical thinking and risk-benefit analysis as well as an understanding of chemical principles. This paper summarizes the origin, development, content, pedagogy, evaluation, and influence of Chemistry in Context and considers its potential implications for other disciplines and the instruction of science majors.

  19. Growing your green chemistry mindset

    Science.gov (United States)

    Kosmas, Steven

    2017-08-01

    The purpose of this article is not to delineate the steps to move across the continuum to being a greener chemist, but to analyse the cognitive processes involved in fostering a green chemistry growth mindset (GCGM) [Dweck C. (2006) Mindset: The New Psychology of Success. New York, NY: Ballatine]. The focus is on changing the mindset, which inevitably will lead to a more mindful approach to chemistry practices before the laboratory begins. A green chemistry fixed mindset (GCFM) is closed to making improvements, since the attitude is that the techniques and processes in the laboratory are already employing a green chemistry mindset [Dweck C. (2006) Mindset: The New Psychology of Success. New York, NY: Ballatine]. The problem with the GCFM is that it precludes the possibility of making improvements. However, the GCGM employs a continuous, intentional focus on the attitude towards green chemistry, with the ultimate goal being a change in chemistry practices that is greener. The focus of this article will be on the GCGM.

  20. Effective Chemistry Communication in Informal Environments

    Science.gov (United States)

    National Academies Press, 2016

    2016-01-01

    Chemistry plays a critical role in daily life, impacting areas such as medicine and health, consumer products, energy production, the ecosystem, and many other areas. Communicating about chemistry in informal environments has the potential to raise public interest and understanding of chemistry around the world. However, the chemistry community…

  1. 42 CFR 493.839 - Condition: Chemistry.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 5 2010-10-01 2010-10-01 false Condition: Chemistry. 493.839 Section 493.839... These Tests § 493.839 Condition: Chemistry. The specialty of chemistry includes for the purposes of proficiency testing the subspecialties of routine chemistry, endocrinology, and toxicology. ...

  2. Fogwater chemistry at Riverside, California

    Science.gov (United States)

    Munger, J. William; Collett, Jeff; Daube, Bruce; Hoffmann, Michael R.

    Fog, aerosol, and gas samples were collected during the winter of 1986 at Riverside, California. The dominant components of the aerosol were NH 4+, NO 3-, and SO 42-. Gaseous NH 3 was frequently present at levels equal to or exceeding the aerosol NH 4+. Maximum level were 3800, 3100, 690 and 4540 neq m -3 for NH 4+, NO 32- and NH 3(g), respectively. The fogwater collected at Riverside had very high concentrations, particularly of the major aerosol components. Maximum concentrations were 26,000 29,000 and 6200 μM for NH 4+, NO 3- and SO 42-, respectively. pH values in fogwater ranged from 2.3 to 5.7. Formate and acetate concentrations as high as 1500 and 580 μM, respectively, were measured. The maximum CH 2O concentration was 380 μM. Glyoxal and methylglyoxal were found in all the samples; their maximum concentrations were 280 and 120 μM, respectively. Comparison of fogwater and aerosol concentrations indicates that scavenging of precursor aerosol by fog droplets under the conditions at Riverside is less than 100% efficient. The chemistry at Riverside is controlled by the balance between HNO 3 production from NO x emitted throughout the Los Angeles basin and NH 3 emitted from dairy cattle feedlots just west of Riverside. The balance is controlled by local mixing. Acid fogs result at Riverside when drainage flows from the surrounding mountains isolate the site from the NH 3 source. Continued formation of HNO 3(g) in this air mass eventually depletes the residual NH 3(g). A simple box model that includes deposition, fog scavenging, and dilution is used to assess the effect of curtailing the dairy cattle feedlot operations. The calculations suggest that the resulting reduction of NH 3 levels would decrease the total NO 3- in the atmosphere, but nearly all remaining NO 3- would exist as HNO 3. Fogwater in the basin would be uniformly acidic.

  3. Chemistry of natural products: A veritable approach to the ...

    African Journals Online (AJOL)

    Even with the advent of newer technologies such as combinatorial chemistry, robotics, high throughput screening (HTS), bioinformatics, and in silico molecular modelling, natural products still play a crucial role in drug discovery. This is because they provide an unparalleled range of chemical diversity on which the newer ...

  4. A tracer aided study on silicon chemistry in biological systems

    NARCIS (Netherlands)

    Brasser, H.J.

    2009-01-01

    Silicon (Si) is omnipresent in nature, and it is involved in important but diverse roles in a broad range of organisms, including diatoms, higher plants and humans. Some organisms, like the diatoms, need high amounts of silicon, and master silicon chemistry to a high extend using several enzymes.

  5. Minnesota Pheasant Range

    Data.gov (United States)

    Minnesota Department of Natural Resources — This dataset delineates the spatial range of wild pheasant populations in Minnesota as of 2002 by dividing the MN state boundary into 2 units: pheasant range and...

  6. Substring Range Reporting

    DEFF Research Database (Denmark)

    Bille, Philip; Gørtz, Inge Li

    2014-01-01

    We revisit various string indexing problems with range reporting features, namely, position-restricted substring searching, indexing substrings with gaps, and indexing substrings with intervals. We obtain the following main results. We give efficient reductions for each of the above problems...... to a new problem, which we call substring range reporting. Hence, we unify the previous work by showing that we may restrict our attention to a single problem rather than studying each of the above problems individually. We show how to solve substring range reporting with optimal query time and little...... for substring range reporting generalize to substring range counting and substring range emptiness variants. We also obtain non-trivial time-space trade-offs for these problems. Our bounds for substring range reporting are based on a novel combination of suffix trees and range reporting data structures...

  7. 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.

  8. Supported organometallic complexes: Surface chemistry, spectroscopy, and catalysis

    Energy Technology Data Exchange (ETDEWEB)

    Marks, T.J.

    1992-02-01

    The long-range goal of this project is to elucidate and understand the surface chemistry and catalytic properties of well-defined, highly-reactive organometallic molecules (principally based upon abundant actinide, lanthanide, and early transition elements) adsorbed on metal oxides and halides. The nature of the adsorbed species is probed by a battery of chemical and physicochemical techniques, to understand the nature of the molecular-surface coordination chemistry and how this can give rise to extremely high catalytic activity. A complementary objective is to delineate the scope and mechanisms of the heterogeneous catalytic reactions, as well as to relate them both conceptually and functionally to model systems generated in solution.

  9. Concepts and methods in modern theoretical chemistry statistical mechanics

    CERN Document Server

    Ghosh, Swapan Kumar

    2013-01-01

    Concepts and Methods in Modern Theoretical Chemistry: Statistical Mechanics, the second book in a two-volume set, focuses on the dynamics of systems and phenomena. A new addition to the series Atoms, Molecules, and Clusters, this book offers chapters written by experts in their fields. It enables readers to learn how concepts from ab initio quantum chemistry and density functional theory (DFT) can be used to describe, understand, and predict chemical dynamics. This book covers a wide range of subjects, including discussions on the following topics: Time-dependent DFT Quantum fluid dynamics (QF

  10. Substring Range Reporting

    DEFF Research Database (Denmark)

    Bille, Philip; Gørtz, Inge Li

    2011-01-01

    We revisit various string indexing problems with range reporting features, namely, position-restricted substring searching, indexing substrings with gaps, and indexing substrings with intervals. We obtain the following main results. – We give efficient reductions for each of the above problems...... to a new problem, which we call substring range reporting. Hence, we unify the previous work by showing that we may restrict our attention to a single problem rather than studying each of the above problems individually. – We show how to solve substring range reporting with optimal query time and little...... range reporting are based on a novel combination of suffix trees and range reporting data structures. The reductions are simple and general and may apply to other combinations of string indexing with range reporting....

  11. Pedagogical Contend Knowledge about green chemistry: for university professors of chemistry

    OpenAIRE

    Diana Lineth Parga Lozano

    2015-01-01

    The search area of interesting to researcher in Science education is the green curricula of teaching of teacher. Therefor, the next consideration take into account the university teacher of chemistry teacher in relation to knowledge that they have to teach the sustainable chemistry, environmental chemistry and the green chemistry, like levels of green chemistry when teach to chemistry teacher. The methodology included a documental study, in the national congress in Brazil about of...

  12. Compact Antenna Range

    Data.gov (United States)

    Federal Laboratory Consortium — Facility consists of a folded compact antenna range including a computer controlled three axis position table, parabolic reflector and RF sources for the measurement...

  13. Dryden Aeronautical Test Range

    Data.gov (United States)

    Federal Laboratory Consortium — Recently redesignated to honor Dr. Hugh L. Dryden, NASA's Dryden Aeronautical Test Range (DATR) supports aerospace flight research and technology integration, space...

  14. Making Decisions by Analytical Chemistry

    DEFF Research Database (Denmark)

    Andersen, Jens Enevold Thaulov

    . These discrepancies are very unfortunate because erroneous conclusions may arise from an otherwise meticulous and dedicated effort of research staff. This may eventually lead to unreliable conclusions thus jeopardizing investigations of environmental monitoring, climate changes, food safety, clinical chemistry......It has been long recognized that results of analytical chemistry are not flawless, owing to the fact that professional laboratories and research laboratories analysing the same type of samples by the same type of instruments are likely to obtain significantly different results. The European...... of accuracy published in research literature. The possible deviations are suspected to originate from long-term variations of detection systems of instrumental analysis, and the impact on these findings on future measurements of analytical chemistry is discussed....

  15. Mass spectrometry. [in organic chemistry

    Science.gov (United States)

    Burlingame, A. L.; Shackleton, C. H. L.; Howe, I.; Chizhov, O. S.

    1978-01-01

    A review of mass spectrometry in organic chemistry is given, dealing with advances in instrumentation and computer techniques, selected topics in gas-phase ion chemistry, and applications in such fields as biomedicine, natural-product studies, and environmental pollution analysis. Innovative techniques and instrumentation are discussed, along with chromatographic-mass spectrometric on-line computer techniques, mass spectral interpretation and management techniques, and such topics in gas-phase ion chemistry as electron-impact ionization and decomposition, photoionization, field ionization and desorption, high-pressure mass spectrometry, ion cyclotron resonance, and isomerization reactions of organic ions. Applications of mass spectrometry are examined with respect to bio-oligomers and their constituents, biomedically important substances, microbiology, environmental organic analysis, and organic geochemistry.

  16. Organometallic frustrated Lewis pair chemistry.

    Science.gov (United States)

    Erker, Gerhard

    2011-08-07

    Frustrated Lewis pairs are playing an increasingly important role in organometallic chemistry. Examples are presented and discussed where organometallic systems themselves serve as the Lewis base or Lewis acid components in frustrated Lewis pair chemistry, mostly through their attached functional groups. Activation of dihydrogen takes place easily in many of these systems. This may lead to the generation of novel catalyst systems but also in many cases to the occurrence of specific reactions at the periphery of the organometallic frameworks. Increasingly, FLP reactions are used to carry out functional group conversions in organometallic systems under mild reaction conditions. The limits of typical FLP reactivity are explored with selected organometallic examples, a discussion that points toward new developments, such as the discovery of facile new 1,1-carboboration reactions. Learning more and more about the broad spectrum of frustrated Lewis pair chemistry helps us to find novel reactions and applications.

  17. Problems in structural inorganic chemistry

    CERN Document Server

    Li, Wai-Kee; Mak, Thomas Chung Wai; Mak, Kendrew Kin Wah

    2013-01-01

    This book consists of over 300 problems (and their solutions) in structural inorganic chemistry at the senior undergraduate and beginning graduate level. The topics covered comprise Atomic and Molecular Electronic States, Atomic Orbitals, Hybrid Orbitals, Molecular Symmetry, Molecular Geometry and Bonding, Crystal Field Theory, Molecular Orbital Theory, Vibrational Spectroscopy, and Crystal Structure. The central theme running through these topics is symmetry, molecular or crystalline. The problems collected in this volume originate in examination papers and take-home assignments that have been part of the teaching of the book's two senior authors' at The Chinese University of Hong Kong over the past four decades. The authors' courses include Chemical Bonding, Elementary Quantum Chemistry, Advanced Inorganic Chemistry, X-Ray Crystallography, etc. The problems have been tested by generations of students taking these courses.

  18. Recent advances in click chemistry applied to dendrimer synthesis.

    Science.gov (United States)

    Arseneault, Mathieu; Wafer, Caroline; Morin, Jean-François

    2015-05-20

    Dendrimers are monodisperse polymers grown in a fractal manner from a central point. They are poised to become the cornerstone of nanoscale devices in several fields, ranging from biomedicine to light-harvesting. Technical difficulties in obtaining these molecules has slowed their transfer from academia to industry. In 2001, the arrival of the "click chemistry" concept gave the field a major boost. The flagship reaction, a modified Hüisgen cycloaddition, allowed researchers greater freedom in designing and building dendrimers. In the last five years, advances in click chemistry saw a wider use of other click reactions and a notable increase in the complexity of the reported structures. This review covers key developments in the click chemistry field applied to dendrimer synthesis from 2010 to 2015. Even though this is an expert review, basic notions and references have been included to help newcomers to the field.

  19. Mathematical challenges from theoretical/computational chemistry

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-12-31

    The committee believes that this report has relevance and potentially valuable suggestions for a wide range of readers. Target audiences include: graduate departments in the mathematical and chemical sciences; federal and private agencies that fund research in the mathematical and chemical sciences; selected industrial and government research and development laboratories; developers of software and hardware for computational chemistry; and selected individual researchers. Chapter 2 of this report covers some history of computational chemistry for the nonspecialist, while Chapter 3 illustrates the fruits of some past successful cross-fertilization between mathematical scientists and computational/theoretical chemists. In Chapter 4 the committee has assembled a representative, but not exhaustive, survey of research opportunities. Most of these are descriptions of important open problems in computational/theoretical chemistry that could gain much from the efforts of innovative mathematical scientists, written so as to be accessible introductions to the nonspecialist. Chapter 5 is an assessment, necessarily subjective, of cultural differences that must be overcome if collaborative work is to be encouraged between the mathematical and the chemical communities. Finally, the report ends with a brief list of conclusions and recommendations that, if followed, could promote accelerated progress at this interface. Recognizing that bothersome language issues can inhibit prospects for collaborative research at the interface between distinctive disciplines, the committee has attempted throughout to maintain an accessible style, in part by using illustrative boxes, and has included at the end of the report a glossary of technical terms that may be familiar to only a subset of the target audiences listed above.

  20. Sustainable Chemistry at Sungkyunkwan University.

    Science.gov (United States)

    Park, Nam-Gyu

    2015-07-20

    Special Issue: Sustainable Chemistry at Sungkyunkwan University. Sustainable chemistry is key to the development of efficient renewable energies, which will become more and more important in order to combat global warming. In this Editorial, guest editor Prof. Nam-Gyu Park describes the context of this Special Issue on top-quality research towards sustainability performed at Sungkyunkwan University (SKKU) in Korea. Scientists at SKKU work on, for example, photovoltaic solar cells to generate low-cost electricity, lithium batteries and capacitors to store electricity, piezoelectric nanogenerators, thermoelectric devices, hydrogen generation, and fuel cells. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Theoretical chemistry advances and perspectives

    CERN Document Server

    Eyring, Henry

    1977-01-01

    Theoretical Chemistry: Advances and Perspectives, Volume 2 covers all aspects of theoretical chemistry.This book reviews the techniques that have been proven successful in the study of interatomic potentials in order to describe the interactions between complex molecules. The ground state properties of the interacting electron gas when a magnetic field is present are also elaborated, followed by a discussion on the Gellman-Brueckner-Macke theory of the correlation energy that has applications in atomic and molecular systems.This volume considers the instability of the Hartree-Fock ground state

  2. Analytical Chemistry: A Literary Approach

    Science.gov (United States)

    Lucy, Charles A.

    2000-04-01

    The benefits of incorporating real-world examples of chemistry into lectures and lessons is reflected by the recent inclusion of the Teaching with Problems and Case Studies column in this Journal. However, these examples lie outside the experience of many students, and so much of the impact of "real-world" examples is lost. This paper provides an anthology of references to analytical chemistry techniques from history, popular fiction, and film. Such references are amusing to both instructor and student. Further, the fictional descriptions can serve as a focal point for discussions of a technique's true capabilities and limitations.

  3. On Range of Skill

    DEFF Research Database (Denmark)

    Hansen, Thomas Dueholm; Miltersen, Peter Bro; Sørensen, Troels Bjerre

    2008-01-01

    size (and doubly exponential in its depth). We also provide techniques that yield concrete bounds for unbalanced game trees and apply these to estimate the Range of Skill of Tic-Tac-Toe and Heads-Up Limit Texas Hold'em Poker. In particular, we show that the Range of Skill of Tic-Tac-Toe is more than...

  4. Range Scheduling Aid (RSA)

    Science.gov (United States)

    Logan, J. R.; Pulvermacher, M. K.

    1991-01-01

    Range Scheduling Aid (RSA) is presented in the form of the viewgraphs. The following subject areas are covered: satellite control network; current and new approaches to range scheduling; MITRE tasking; RSA features; RSA display; constraint based analytic capability; RSA architecture; and RSA benefits.

  5. Integrating Computational Chemistry into the Physical Chemistry Curriculum

    Science.gov (United States)

    Johnson, Lewis E.; Engel, Thomas

    2011-01-01

    Relatively few undergraduate physical chemistry programs integrate molecular modeling into their quantum mechanics curriculum owing to concerns about limited access to computational facilities, the cost of software, and concerns about increasing the course material. However, modeling exercises can be integrated into an undergraduate course at a…

  6. Integrating Particulate Representations into AP Chemistry and Introductory Chemistry Courses

    Science.gov (United States)

    Prilliman, Stephen G.

    2014-01-01

    The College Board's recently revised curriculum for advanced placement (AP) chemistry places a strong emphasis on conceptual understanding, including representations of particle phenomena. This change in emphasis is informed by years of research showing that students could perform algorithmic calculations but not explain those calculations…

  7. Analytical Chemistry Laboratory. Progress report for FY 1996

    Energy Technology Data Exchange (ETDEWEB)

    Green, D.W.; Boparai, A.S.; Bowers, D.L.

    1996-12-01

    The purpose of this report is to summarize the activities of the Analytical Chemistry Laboratory (ACL) at Argonne National Laboratory (ANL) for Fiscal Year (FY) 1996. This annual report is the thirteenth for the ACL. It describes effort on continuing and new projects and contributions of the ACL staff to various programs at ANL. The ACL operates in the ANL system as a full-cost-recovery service center, but has a mission that includes a complementary research and development component: The Analytical Chemistry Laboratory will provide high-quality, cost-effective chemical analysis and related technical support to solve research problems of our clients -- Argonne National Laboratory, the Department of Energy, and others -- and will conduct world-class research and development in analytical chemistry and its applications. Because of the diversity of research and development work at ANL, the ACL handles a wide range of analytical chemistry problems. Some routine or standard analyses are done, but the ACL usually works with commercial laboratories if our clients require high-volume, production-type analyses. It is common for ANL programs to generate unique problems that require significant development of methods and adaption of techniques to obtain useful analytical data. Thus, much of the support work done by the ACL is very similar to our applied analytical chemistry research.

  8. Final Report - Low Temperature Combustion Chemistry And Fuel Component Interactions

    Energy Technology Data Exchange (ETDEWEB)

    Wooldridge, Margaret [Univ. of Michigan, Ann Arbor, MI (United States)

    2017-02-24

    Recent research into combustion chemistry has shown that reactions at “low temperatures” (700 – 1100 K) have a dramatic influence on ignition and combustion of fuels in virtually every practical combustion system. A powerful class of laboratory-scale experimental facilities that can focus on fuel chemistry in this temperature range is the rapid compression facility (RCF), which has proven to be a versatile tool to examine the details of fuel chemistry in this important regime. An RCF was used in this project to advance our understanding of low temperature chemistry of important fuel compounds. We show how factors including fuel molecular structure, the presence of unsaturated C=C bonds, and the presence of alkyl ester groups influence fuel auto-ignition and produce variable amounts of negative temperature coefficient behavior of fuel ignition. We report new discoveries of synergistic ignition interactions between alkane and alcohol fuels, with both experimental and kinetic modeling studies of these complex interactions. The results of this project quantify the effects of molecular structure on combustion chemistry including carbon bond saturation, through low temperature experimental studies of esters, alkanes, alkenes, and alcohols.

  9. Physics and Its Interfaces with Medicinal Chemistry and Drug Design

    Science.gov (United States)

    Santos, Ricardo N.; Andricopulo, Adriano D.

    2013-08-01

    Medicinal chemistry is a multidisciplinary subject that integrates knowledge from a variety of fields of science, including, but not limited to, chemistry, biology, and physics. The area of drug design involves the cooperative work of scientists with a diverse range of backgrounds and technical skills, trying to tackle complex problems using an integration of approaches and methods. One important contribution to this field comes from physics through studies that attempt to identify and quantify the molecular interactions between small molecules (drugs) and biological targets (receptors), such as the forces that govern the interactions, the thermodynamics of the drug-receptor interactions, and so on. In this context, the interfaces of physics, medicinal chemistry, and drug design are of vital importance for the development of drugs that not only have the right chemistry but also the right intermolecular properties to interact at the macromolecular level, providing useful information about the principles and molecular mechanisms underlying the therapeutic action of drugs. This article highlights some of the most important connections between physics and medicinal chemistry in the design of new drugs.

  10. Home range and travels

    Science.gov (United States)

    Stickel, L.F.; King, John A.

    1968-01-01

    The concept of home range was expressed by Seton (1909) in the term 'home region,' which Burr (1940, 1943) clarified with a definition of home range and exemplified in a definitive study of Peromyscus in the field. Burt pointed out the ever-changing characteristics of home-range area and the consequent absence of boundaries in the usual sense--a finding verified by investigators thereafter. In the studies summarized in this paper, sizes of home ranges of Peromyscus varied within two magnitudes, approximately from 0.1 acre to ten acres, in 34 studies conducted in a variety of habitats from the seaside dunes of Florida to the Alaskan forests. Variation in sizes of home ranges was correlated with both environmental and physiological factors; with habitat it was conspicuous, both in the same and different regions. Food supply also was related to size of home range, both seasonally and in relation to habitat. Home ranges generally were smallest in winter and largest in spring, at the onset of the breeding season. Activity and size also were affected by changes in weather. Activity was least when temperatures were low and nights were bright. Effects of rainfall were variable. Sizes varied according to sex and age; young mice remained in the parents' range until they approached maturity, when they began to travel more widely. Adult males commonly had larger home ranges than females, although there were a number of exceptions. An inverse relationship between population density and size of home range was shown in several studies and probably is the usual relationship. A basic need for activity and exploration also appeared to influence size of home range. Behavior within the home range was discussed in terms of travel patterns, travels in relation to home sites and refuges, territory, and stability of size of home range. Travels within the home range consisted of repeated use of well-worn trails to sites of food, shelter, and refuge, plus more random exploratory travels

  11. Fog water chemistry in Shanghai

    Science.gov (United States)

    Li, Pengfei; Li, Xiang; Yang, Chenyu; Wang, Xinjun; Chen, Jianmin; Collett, Jeffrey L., Jr.

    2011-08-01

    With the aim of understanding the fog chemistry in a Chinese megacity, twenty-six fog water samples were collected in urban Shanghai from March 2009 to March 2010. The following parameters were measured: pH, electrical conductivity (EC), ten inorganic major ions ( SO42-, NO3-, NO2-, F -, Cl -, Na +, K +, Ca 2+, Mg 2+, NH4+) and four major organic acids (CH 3COO -, HCOO -, CO42-, MSA). The total ionic concentration (TIC) and EC of fog samples were one or two orders of magnitude higher than those often found in Europe, North America and other Asian countries. Pollutants were expected to be mainly from local sources, including factories, motor vehicle emissions and civil construction. Non-local sources such as moderate- and long-range transport of sea salt also contributed to pollution levels in fog events as indicated by back trajectory analysis. The pH of the fog water collected during the monitoring period varied from 4.68 to 6.58; acidic fogs represented about 30.8% of the total fog events during this period. The fog water was characterized by high concentrations of SO42- (20.0% of measured TIC), NO3- (17.1%), NH4+ (28.3%) and Ca 2+ (14.4%). SO42- and NO3-, the main precursors of fog acidity, were related to burning fossil fuels and vehicle emissions, respectively. NH4+, originating from the scavenging of gaseous ammonia and particulate ammonium nitrate and ammonium sulfate, and Ca 2+, originating from the scavenging of coarse particles, acted as acid neutralizers and were the main cause for the relatively high pH of fogs in Shanghai. The ratio of ( SO42- + NO3-)/( NH4+ + Ca 2+) was lower than 1, indicating the alkaline nature of the fog water. A high ratio of NO3-/ SO42- and low ratio of HCOO -/CH 3COO - were consistent with large contributions from vehicular emissions that produce severe air pollution in megacities.

  12. Developing an online chemistry laboratory for non-chemistry majors

    Science.gov (United States)

    Poole, Jacqueline H.

    Distance education, also known as online learning, is student-centered/self-directed educational opportunities. This style of learning is expanding in scope and is increasingly being accepted throughout the academic curriculum as a result of its flexibility for the student as well as the cost-effectiveness for the institution. Nevertheless, the introduction of online science courses including chemistry and physics have lagged behind due to the challenge of re-creation of the hands-on laboratory learning experience. This dissertation looks at the effectiveness of the design of a series of chemistry laboratory experiments for possible online delivery that provide students with simulated hands-on experiences. One class of college Chemistry 101 students conducted chemistry experiments inside and outside of the physical laboratory using instructions on Blackboard and Late Nite Labs(TM). Learning outcomes measured by (a) pretests, (b) written laboratory reports, (c) posttest assessments, (d) student reactions as determined by a questionnaire, and (e) a focus group interview were utilized to compare both types of laboratory experiences. The research findings indicated learning outcomes achieved by students outside of the traditional physical laboratory were statistically greater than the equivalent face-to-face instruction in the traditional laboratory. Evidence from student reactions comparing both types of laboratory formats (online and traditional face-to-face) indicated student preference for the online laboratory format. The results are an initial contribution to the design of a complete sequence of experiments that can be performed independently by online students outside of the traditional face-to-face laboratory that will satisfy the laboratory requirement for the two-semester college Chemistry 101 laboratory course.

  13. Monitoring cycle water chemistry in fossil plants

    Energy Technology Data Exchange (ETDEWEB)

    Aschoff, A.F.; Sopocy, D.M.; Eglar, D.T. (Sargent and Lundy, Chicago, IL (United States)); Jonas, O. (Jonas, Inc., Wilmington, DE (United States)); Rice, J.K. (Rice (James K.), Chartered (United States)); Stauffer, C.C.; Allmon, W.E. (Babcock and Wilcox Co., Alliance, OH (United States))

    1991-10-01

    EPRI report CS-4629, published in 1986, contains operating cycle chemistry guidelines to assist utilities in reducing water and steam contamination and resulting corrosion, scaling, and deposition. These guidelines were based on consensus opinion utilizing information then available and were not validated through actual plant testing. The objectives of this project are: to monitor the major parameters of cycle chemistry in a range of fossil-fired plants; to compare the monitored parameters with the interim guidelines. The project team designed and constructed state-of-the-art instrumentation and data acquisition systems to measure and record continuously the chemical parameters specified in the interim consensus guidelines (ICG). The team then installed and operated these systems at four utility power plants. Nine international organizations conducted parallel monitoring efforts on 29 generating units. An industrial fossil plant group of 14 utilities and boiler and turbine manufacturers reviewed the monitoring results from each of the plants as did the participating international organizations. 137 figs., 43 tabs.

  14. Microwaves in organic chemistry and organic chemical

    Directory of Open Access Journals (Sweden)

    Mijin Dušan Ž.

    2005-01-01

    Full Text Available The usual way of applying heat to a chemical reaction is the use of a Bunsen burner, an oil or some other type of bath, or an electric heater. In inorganic chemistry, microwave technology has been used since the late 1970s while it has been implemented in organic chemistry since the mid-1980s. Microwave heating has been used in the food industry for almost fifty years. The shorter reaction times and expanded reaction range that is offered by microwave technology are suited to the increased demands in industry. For example, there is a requirement in the pharmaceutical industry for a higher number of a novel chemical entities to be produced, which requires chemists to employ a number of resources to reduce time for the production of compounds. Also, microwaves are used in the food industry, as well as in the pyrolysis of waste materials, sample preparation, the solvent extraction of natural products and the hydrolysis of proteins and peptides.

  15. Cafeteria-Style Grading in General Chemistry

    Science.gov (United States)

    Goodwin, John A.; Gilbert, Brian D.

    2001-04-01

    Self-selected individual course-grade weighting schemes allow students personal choice of course components in the general chemistry sequence at Coastal Carolina University. With the availability of a wide range of commercial and academically produced pedagogical resources, students can select materials that best suit their own learning styles, social situations, and motivation level. Our students use a signed contract to indicate their preferred grade-weighting schemes for determination of the course grade. In doing so, they choose from course components that include peer-led team learning (PLTL) in the Workshop Chemistry (WSC) model, computer-assisted instruction (CAI) using the ChemSkill Builder (CSB) software, a variety of in-class quizzes and group problem-solving exercises, written exams, and the final written exam. Minimum percentage values are required of all components except WSC and CSB, which have been completely optional graded course components at CCU since the summer of 1999. Comparison of student success in the course and content learning suggests that the improvements observed with introduction of a gamut of activities increase even more when the cafeteria-style grading is implemented.

  16. IV. Health physics and chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Garden, N.B.; Moyer, B.J.

    1948-05-24

    This report describes progress on the development of equipment and techniques to accomplish the goal of control and trapping of radioactive sustances. Emphasis is on simplicity reproducibiolity, and universal use. Also illustrated is the Health Chemistry Organization set-up of personnel.

  17. 2001 Chemistry N abel Prize

    Indian Academy of Sciences (India)

    Parkinson's disease (Box 8). Thus, the spectacular success of this L-DOPA synthesis has significantly contributed to the explosive growth of research aimed at the development and application of other catalytic asymmetric reactions in ensuing years. In 1980, the other 2001 Chemistry Nobel Laureate, Noyori discovered the ...

  18. Superheavy element chemistry at GARIS

    Directory of Open Access Journals (Sweden)

    Haba Hiromitsu

    2016-01-01

    Full Text Available A gas-jet transport system has been installed to the RIKEN GAs-filled Recoil Ion Separator, GARIS to start up SuperHeavy Element (SHE chemistry. This system is a promising approach for exploring new frontiers in SHE chemistry: background radioactivities from unwanted by-products are suppressed, a high gas-jet transport yield is achieved, and new chemical reactions can be investigated. Useful radioisotopes of 261Rfa,b, 262Db, and 265Sga,b for chemical studies were produced in the reactions of 248Cm(18O,5n261Rfa,b, 248Cm(19F,5n262Db, and 248Cm(22Ne,5n265Sga,b, respectively. They were successfully extracted to a chemistry laboratory by the gas-jet method. Production and decay properties of 261Rfa,b, 262Db, and 265Sga,b were investigated in detail with the rotating wheel apparatus for α- and spontaneous fission spectrometry. Present status and perspectives of the SHE chemistry at GARIS are also briefly presented.

  19. Botany, Chemistry, and Tropical Development.

    Science.gov (United States)

    Headrick, Daniel R.

    1996-01-01

    Examines the role played by botany and chemistry in the development, exploitation, and later deterioration of tropical economies. Although near equals in 19th-century international trade, the development of synthetics by European scientists in the early 20th century crippled the tropical economies. Research, innovation, and investment protected…

  20. and Second-Year Chemistry

    African Journals Online (AJOL)

    NICO

    E-mail: leonard.smith@uct.ac.za. Received 30 May 2013, revised 25 June 2013, accepted 28 June 2013. ABSTRACT. This paper uses multivariate analysis to estimate the impact of educational interventions in the first-year academic development chemistry courses on students' final course marks. The cohorts for seven ...

  1. Surface chemistry in three dimensions

    DEFF Research Database (Denmark)

    Bollinger, Mikkel; Jacobsen, Karsten Wedel; Nørskov, Jens Kehlet

    2000-01-01

    the usual single surface ('2D') process because indirect adsorbate-adsorbate interactions in the transition state are absent in the '3D' case. The prospects for STM-induced single molecule chemistry and for '3D' catalysts are discussed. (C) 2000 Elsevier Science B.V. All rights reserved....

  2. Organic chemistry in Titan's atmosphere

    Science.gov (United States)

    Scattergood, T.

    1982-01-01

    Laboratory photochemical simulations and other types of chemical simulations are discussed. The chemistry of methane, which is the major known constituent of Titan's atmosphere was examined with stress on what can be learned from photochemistry and particle irradiation. The composition of dust that comprises the haze layer was determined. Isotope fractionation in planetary atmospheres is also discussed.

  3. Ullmann's Encyclopedia of Industrial Chemistry.

    Science.gov (United States)

    Chadwick, Sharon S.

    1988-01-01

    This review compares "Ullmann's Encyclopedia of Industrial Chemistry" with the "Kirk-Othmer Encyclopedia of Chemical Technology," two prominent encyclopedias of chemical technology and industry. Cost, quantity of information, organization, illustrations, authorship, abbreviations, online availability, and content of articles are discussed. (MES)

  4. 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 70 (2017). DOWNLOAD FULL TEXT Open Access DOWNLOAD FULL TEXT Subscription or Fee Access. Table of Contents.

  5. Plasma chemistry and organic synthesis

    Science.gov (United States)

    Tezuka, M.

    1980-01-01

    The characteristic features of chemical reactions using low temperature plasmas are described and differentiated from those seen in other reaction systems. A number of examples of applications of plasma chemistry to synthetic reactions are mentioned. The production of amino acids by discharge reactions in hydrocarbon-ammonia-water systems is discussed, and its implications for the origins of life are mentioned.

  6. Teaching Techniques in Clinical Chemistry.

    Science.gov (United States)

    Wilson, Diane

    This master's thesis presents several instructional methods and techniques developed for each of eleven topics or subject areas in clinical chemistry: carbohydrate metabolism, lipid metabolism, diagnostic enzymology, endocrinology, toxicology, quality control, electrolytes, acid base balance, hepatic function, nonprotein nitrogenous compounds, and…

  7. Electron Driven Chemistry In Microreactors

    NARCIS (Netherlands)

    Agiral, A.

    2009-01-01

    This thesis describes the development of novel process windows by the combination of atmospheric pressure plasmas with microreaction technology. In the first chapter, recent literature on microreactor technology and non-equilibirum microplasma chemistry is discussed. The focus is on microplasmas in

  8. Chemistry Perfumes Your Daily Life

    Science.gov (United States)

    Fortineau, Anne-Dominique

    2004-01-01

    A synopsis on the history of perfumery is presented, along with the various processes accessible for obtaining natural perfume constituents, and creation of synthetic chemicals. The important contribution of organic chemists in the invention of perfumes, aspects of fragrance chemistry, and general information on the perfume industry are…

  9. Green chemistry for chemical synthesis

    Science.gov (United States)

    Li, Chao-Jun; Trost, Barry M.

    2008-01-01

    Green chemistry for chemical synthesis addresses our future challenges in working with chemical processes and products by inventing novel reactions that can maximize the desired products and minimize by-products, designing new synthetic schemes and apparati that can simplify operations in chemical productions, and seeking greener solvents that are inherently environmentally and ecologically benign. PMID:18768813

  10. Solid State and Materials Chemistry

    Indian Academy of Sciences (India)

    Unknown

    It gives us immense pleasure to present this Special Issue of the Proceedings of the Indian. Academy of Sciences (Chemical Sciences) to mark the Silver Jubilee of the Solid State and Structural Chemistry Unit (SSCU), Indian Institute of Science, Bangalore. This Unit was created by Professor C N R Rao, FRS, at the Institute ...

  11. Modern Trends in Inorganic Chemistry

    Indian Academy of Sciences (India)

    Unknown

    Chemical. Sciences) is based on 18 papers presented at the Ninth Symposium on Modern Trends in. Inorganic Chemistry (MTIC-IX) held during 12–14 December 2001 at the Indian. Association for the Cultivation of Science, Kolkata. We have also ...

  12. Atmospheric chemistry over southern Africa

    Science.gov (United States)

    Gatebe, Charles K.; Levy, Robert C.; Thompson, Anne M.

    2012-03-01

    Changing Chemistry in a Changing Climate: Human and Natural Impacts Over Southern Africa (C4-SAR); Midrand, South Africa, 31 May to 3 June 2011 During the southern African dry season, regional haze from mixed industrial pollution, biomass burning aerosol and gases from domestic and grassland fires, and biogenic sources from plants and soils is worsened by a semipermanent atmospheric gyre over the subcontinent. These factors were a driver of several major international field campaigns in the 1990s and early 2000s and attracted many scientists to the region. Some researchers were interested in understanding fundamental processes governing chemistry of the atmosphere and interaction with climate change. Others found favorable conditions for evaluating satellite- derived measurements of atmospheric properties and a changing land surface. With that background in mind a workshop on atmospheric chemistry was held in South Africa. Sponsored by the International Commission on Atmospheric Chemistry and Global Pollution (ICACGP; http://www.icacgp.org/), the workshop received generous support from Eskom, the South African power utility; and the Climatology Research Group of the University of the Witwatersrand, Johannesburg, South Africa.

  13. Supramolecular chemistry and crystal engineering

    Indian Academy of Sciences (India)

    Advances in supramolecular chemistry and crystal engineering reported from India within the last decade are highlighted in the categories of new intermolecular interactions, designed supramolecular architectures, network structures, multi-component host-guest systems, cocrystals, and polymorphs. Understanding ...

  14. Destruction Chemistry of Mustard Simulants

    Science.gov (United States)

    2008-07-04

    organosulfur compounds under both pyrolytic and oxidative conditions. We focus on the destruction of alkyl sulfides that are surrogates for chemical... organosulfur , oxidation, pyrolysis, chemical kinetic mechanism, thermochemistry, reaction, kinetics, flow reactor, GC/MS, FTIR, mustard agent simulant, CWA...destruction chemistry of organosulfur compounds under both pyrolytic and oxidative conditions. We focus on the destruction of alkyl sulfides that are

  15. Chemistry of high temperature superconductors

    CERN Document Server

    1991-01-01

    This review volume contains the most up-to-date articles on the chemical aspects of high temperature oxide superconductors. These articles are written by some of the leading scientists in the field and includes a comprehensive list of references. This is an essential volume for researchers working in the fields of ceramics, materials science and chemistry.

  16. The aqueous chemistry of oxides

    CERN Document Server

    Bunker, Bruce C

    2016-01-01

    The Aqueous Chemistry of Oxides is a comprehensive reference volume and special topics textbook that explores all of the major chemical reactions that take place between oxides and aqueous solutions. The book highlights the enormous impact that oxide-water reactions have in advanced technologies, materials science, geochemistry, and environmental science.

  17. Supramolecular chemistry and crystal engineering

    Indian Academy of Sciences (India)

    Advances in supramolecular chemistry and crystal engineering reported from India within the last decade are highlighted in the categories of new intermolecular interactions, designed supramolecular architectures, network structures, multi-component host–guest systems, cocrys- tals, and polymorphs. Understanding ...

  18. Educational benefits of green chemistry

    Science.gov (United States)

    Desmond, Serenity; Ray, Christian; Andino Martínez, José G.

    2017-08-01

    In this article, we present our current state of affairs in the "greening" of general chemistry laboratories, at the University of Illinois at Urbana-Champaign. We recognize the need to quantify our environmental mark and what we plan to do to continue to strive to make our work more sustainable and educational.

  19. Analytical Chemistry of Perfluoroalkylated Substances

    NARCIS (Netherlands)

    de Voogt, P.; Saez Ribas, M.

    2006-01-01

    Polyfluorinated alkylated substances have recently gainedscientific interest because they have been found to be present in appreciable concentrations in human serum, in surface waters, and in tissues of wildlife from remote areas. The developments in analytical chemistry of these mainly neutral or

  20. Long range image enhancement

    CSIR Research Space (South Africa)

    Duvenhage, B

    2015-11-01

    Full Text Available and Vision Computing, Auckland, New Zealand, 23-24 November 2015 Long Range Image Enhancement Bernardt Duvenhage Council for Scientific and Industrial Research South Africa Email: bduvenhage@csir.co.za Abstract Turbulent pockets of air...

  1. SNOWY RANGE WILDERNESS, WYOMING.

    Science.gov (United States)

    Houston, Robert S.; Bigsby, Philip R.

    1984-01-01

    A mineral survey of the Snowy Range Wilderness in Wyoming was undertaken and was followed up with more detailed geologic and geochemical surveys, culminating in diamond drilling of one hole in the Snowy Range Wilderness. No mineral deposits were identified in the Snowy Range Wilderness, but inasmuch as low-grade uranium and associated gold resources were identified in rocks similar to those of the northern Snowy Range Wilderness in an area about 5 mi northeast of the wilderness boundary, the authors conclude that the northern half of the wilderness has a probable-resource potential for uranium and gold. Closely spaced drilling would be required to completely evaluate this mineral potential. The geologic terrane precludes the occurrence of fossil fuels.

  2. Atlantic Test Range (ATR)

    Data.gov (United States)

    Federal Laboratory Consortium — ATR controls fully-instrumented and integrated test ranges that provide full-service support for cradle-to-grave testing. Airspace and surface target areas are used...

  3. Light Detection And Ranging

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — LiDAR (Light Detection and Ranging) discrete-return point cloud data are available in the American Society for Photogrammetry and Remote Sensing (ASPRS) LAS format....

  4. On Range of Skill

    DEFF Research Database (Denmark)

    Hansen, Thomas Dueholm; Miltersen, Peter Bro; Sørensen, Troels Bjerre

    2008-01-01

    is a small number, but only gave heuristic arguments for this. In this paper, we provide the first methods for rigorously estimating the Range of Skill of a given game. We provide some general, asymptotic bounds that imply that the Range of Skill of a perfectly balanced game tree is almost exponential in its......At AAAI'07, Zinkevich, Bowling and Burch introduced the Range of Skill measure of a two-player game and used it as a parameter in the analysis of the running time of an algorithm for finding approximate solutions to such games. They suggested that the Range of Skill of a typical natural game...... size (and doubly exponential in its depth). We also provide techniques that yield concrete bounds for unbalanced game trees and apply these to estimate the Range of Skill of Tic-Tac-Toe and Heads-Up Limit Texas Hold'em Poker. In particular, we show that the Range of Skill of Tic-Tac-Toe is more than...

  5. Organometallic chemistry of chiral diphosphazane ligands ...

    Indian Academy of Sciences (India)

    Unknown

    Organometallic chemistry of chiral diphosphazane ligands: Synthesis and structural characterisation. KANNAN RAGHURAMAN, SWADHIN K MANDAL,. T S VENKATAKRISHNAN, SETHARAMPATTU S. KRISHNAMURTHY* and MUNIRATHINAM NETHAJI. Department of Inorganic and Physical Chemistry, Indian Institute of ...

  6. Undergraduate chemistry education: a workshop summary

    National Research Council Canada - National Science Library

    Sawyer, Keegan; Alper, Joe

    2014-01-01

    "Undergraduate Chemistry Education is the summary of a workshop convened in May 2013 by the Chemical Science Roundtable of the National Research Council to explore the current state of undergraduate chemistry education...

  7. Halogen Chemistry in the CMAQ Model

    Science.gov (United States)

    Halogens (iodine and bromine) emitted from oceans alter atmospheric chemistry and influence atmospheric ozone mixing ratio. We previously incorporated a representation of detailed halogen chemistry and emissions of organic and inorganic halogen species into the hemispheric Commun...

  8. Radiation chemistry and its application

    Energy Technology Data Exchange (ETDEWEB)

    Majima, Tetsuro [Osaka Univ., Osaka (Japan)

    2013-07-01

    Effects of radiation to human body have been seriously discussed nowadays. These are important issues for the realization of sustainable society. It should be emphasized that various reactive intermediates generated by radiation play important roles in each cases. Radiation chemical studies will provide various reaction-mechanistic aspects on these important issues. Our research group has continuously carried out reaction-mechanistic studies using radiation chemical methods. From these studies, we have obtained a variety of results on basic molecular systems, reactions, materials that are close to practical application, biological systems and so on. Reactive species are generated from the radiation reactions in solution, and can be used as one-electron oxidative and reductive reagent to give selectively radical cation and anion of solute molecules such as various organic and inorganic molecules. Therefore, the radiation chemistry has contributed significantly to chemistry in which one-electron oxidation and reduction play the important role. The kinetics of such redox processes and the following reduction play the important role. The kinetics of such redox processes and the following reactions can be studied in real time with the transition absorption measurement by the pulse radiolysis technique. Even though the target compounds cannot be oxidized and reduced in chemical or electrochemical oxidation and reduction, their one-electron redox can be performed by the electron beam radiation. Therefore, radiation chemistry is very useful technique for basic science. Moreover, application potentials of radiation chemistry are so high for various research subjects. Moreover, application potentials of radiation chemistry are so high for various research subjects.

  9. Analytical Chemistry Laboratory, progress report for FY 1993

    Energy Technology Data Exchange (ETDEWEB)

    1993-12-01

    The purpose of this report is to summarize the activities of the Analytical Chemistry Laboratory (ACL) at Argonne National Laboratory (ANL) for Fiscal Year (FY) 1993 (October 1992 through September 1993). This annual report is the tenth for the ACL and describes continuing effort on projects, work on new projects, and contributions of the ACL staff to various programs at ANL. The Analytical Chemistry Laboratory is a full-cost-recovery service center, with the primary mission of providing a broad range of analytical chemistry support services to the scientific and engineering programs at ANL. The ACL also has research programs in analytical chemistry, conducts instrumental and methods development, and provides analytical services for governmental, educational, and industrial organizations. The ACL handles a wide range of analytical problems. Some routine or standard analyses are done, but it is common for the Argonne programs to generate unique problems that require development or modification of methods and adaption of techniques to obtain useful analytical data. The ACL is administratively within the Chemical Technology Division (CMT), its principal ANL client, but provides technical support for many of the technical divisions and programs at ANL. The ACL has four technical groups--Chemical Analysis, Instrumental Analysis, Organic Analysis, and Environmental Analysis--which together include about 45 technical staff members. Talents and interests of staff members cross the group lines, as do many projects within the ACL.

  10. Drug incompatibility chemistry.

    Science.gov (United States)

    Newton, David W

    2009-02-15

    The chemical interactions that cause drug incompatibility in solutions, with emphasis on the acid-base and ionized-nonionized forms of organic, weak, electrolyte drugs, are examined. When the dilution or mixing of the salt or ionized forms of organic drugs results in precipitation, the most likely cause is formation of the nonionized drug forms. More than 90% of drugs are organic, weak electrolytes, especially those compounded, manufactured, or reconstituted as injections in predominantly ionized or salt forms. Acid-base reactions are the most common causes of drug incompatibility as precipitation of nonionized drug forms. Precipitation is likely when oppositely charged, organic drug ions that contain aromatic rings are combined in relatively strong concentrations. Salts of polyvalent anions and cations are generally less soluble than salts in which both ions are monovalent or in which one ion is monovalent and its opposite ion is polyvalent. The most clinically important potential precipitates among these ions are dibasic and monohydrogen calcium phosphate. Incompatibility of drug and nutrient injections is clinically hazardous. Knowledge of products' chemical facts, organic acid-base equilibria in relation to ionization and nonionization and aqueous solubility, and ranges of pH and ingredient strength from United States Pharmacopeia monographs and product labeling is the foundation of expertise in drug incompatibility. Precipitation in injectable drug solutions should be suspected, particularly when oppositely charged drug salts are mixed in relatively strong concentrations and when pH values of dilutions create more than 1% of nonionized drug forms.

  11. Eleventh international symposium on radiopharmaceutical chemistry

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-12-31

    This document contains abstracts of papers which were presented at the Eleventh International Symposium on Radiopharmaceutical Chemistry. Sessions included: radiopharmaceuticals for the dopaminergic system, strategies for the production and use of labelled reactive small molecules, radiopharmaceuticals for measuring metabolism, radiopharmaceuticals for the serotonin and sigma receptor systems, labelled probes for molecular biology applications, radiopharmaceuticals for receptor systems, radiopharmaceuticals utilizing coordination chemistry, radiolabelled antibodies, radiolabelling methods for small molecules, analytical techniques in radiopharmaceutical chemistry, and analytical techniques in radiopharmaceutical chemistry.

  12. Environmental Chemistry Update

    Science.gov (United States)

    1995-08-01

    111 pg, leading to a body fat concentration of about 40 ppt (12). Lithium Battery AdvancesRechargeable Power SourceRecent advances in lithium ion battery technology may allow these devices to become the rechargeable power source of choice in electric cars of the future. Due to their high voltage, they can store a large amount of energy per given mass or volume of battery. In the past, however, such batteries have been somewhat impractical because they had to be hermetically sealed and required nonaqueous electrolytes due to lithium's violent reaction with water. In the newly developed battery, the electrolyte is water that already contains a high concentration of Li+ ions; elemental lithium (present as LiMn2O4 in one electrode) is unreactive in this medium unless an external connection to the other electrode is made (13). Air-Pollution Control for Power PlantsA process called SNOX, which removes both NOx and SO2 from the flue gases produced by coal-fired power plants, has been developed and demonstrated. The nitrogen oxides are first reduced to N2. The resulting gas is then heated and catalytically oxidized to sulfur trioxide, which is then hydrated to sulfuric acid. More than 90% of the NOx and SO2 were removed from the flue gases in the demonstration held at an Ohio Edison plant (14). Literature Cited Williams, D. Nature 1994, 371, 556. Emsley, J. New Scientist 1994, (Oct 1), 14. McMichael, A. J. American Journal of Epidemiology 1994, 140, 489-499. Chemical and Engineering News 1994, (Oct 10), 5. Santee, M. L. Science 1995, 267, 849-852. Chemical and Engineering News 1994, (Nov 14). Solomon, S. Journal of Geophysical Research 1994, 99, 20491-20499. Wennberg, P. O. Science 1994, 266, 398-404. Viggiano, A. A. Science 1995, 267, 82-84. Summary in Chemistry and Engineering News 1995, (Jan 9), 23. Schottler, S. P.; Eisenreich, S. J. Environmental Science and Technology 1994, 28, 2228-2232. Lang, L. Environmental Health Perspectives 1993, 101, 578-583. Chemical and

  13. DanceChemistry: Helping Students Visualize Chemistry Concepts through Dance Videos

    Science.gov (United States)

    Tay, Gidget C.; Edwards, Kimberly D.

    2015-01-01

    A visual aid teaching tool, the DanceChemistry video series, has been developed to teach fundamental chemistry concepts through dance. These educational videos portray chemical interactions at the molecular level using dancers to represent chemical species. Students reported that the DanceChemistry videos helped them visualize chemistry ideas in a…

  14. Moving Chemistry Education into 3D: A Tetrahedral Metaphor for Understanding Chemistry

    Science.gov (United States)

    Mahaffy, Peter

    2006-01-01

    A new conceptual metaphor is proposed to enrich the description of chemistry education and support the many existing efforts to help students make connections with the chemistry found in textbooks. A widely used metaphor for chemistry education takes the shape of a planar triangle that highlights three thinking levels in learning chemistry such as…

  15. The Journal of Kitchen Chemistry: A Tool for Instructing the Preparation of a Chemistry Journal Article

    Science.gov (United States)

    Meyers, Jonathan K.; LeBaron, Tyler W.; Collins, David C.

    2014-01-01

    Writing assignments are typically incorporated into chemistry courses in an attempt to enhance the learning of chemistry or to teach technical writing to chemistry majors. This work addresses the development of chemistry-major writing skills by focusing on the rigorous guidelines and conventions associated with the preparation of a journal…

  16. ENVIRONMENTAL CHEMISTRY CAREERS IN GOVERNMENT AGENCIES

    Science.gov (United States)

    Careers in chemistry and chemistry related fields can be very rewarding and enriching. Being an environmental chemist for a government agency requires a broad background in the field of chemistry. A knowledge of the operation of several analytical and preparatory instruments is...

  17. Reaction-Map of Organic Chemistry

    Science.gov (United States)

    Murov, Steven

    2007-01-01

    The Reaction-Map of Organic Chemistry lists all the most commonly studied reactions in organic chemistry on one page. The discussed Reaction-Map will act as another learning aide for the students, making the study of organic chemistry much easier.

  18. Supplemental Instruction in Physical Chemistry I

    Science.gov (United States)

    Toby, Ellen; Scott, Timothy P.; Migl, David; Kolodzeji, Elizabeth

    2016-01-01

    Physical chemistry I at Texas A&M University is an upper division course requiring mathematical and analytical skills. As such, this course poses a major problem for many Chemistry, Engineering, Biochemistry and Genetics majors. Comparisons between participants and non-participants in Supplemental Instruction for physical chemistry were made…

  19. 42 CFR 493.931 - Routine chemistry.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 5 2010-10-01 2010-10-01 false Routine chemistry. 493.931 Section 493.931 Public... Proficiency Testing Programs by Specialty and Subspecialty § 493.931 Routine chemistry. (a) Program content and frequency of challenge. To be approved for proficiency testing for routine chemistry, a program...

  20. 42 CFR 493.929 - Chemistry.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 5 2010-10-01 2010-10-01 false Chemistry. 493.929 Section 493.929 Public Health... Proficiency Testing Programs by Specialty and Subspecialty § 493.929 Chemistry. The subspecialties under the specialty of chemistry for which a proficiency testing program may offer proficiency testing are routine...

  1. Journal of Applied Chemistry and Agricultural Research

    African Journals Online (AJOL)

    JACAR is a learned journal devoted to the publication of high quality articles in all areas of Agricultural Sciences and Applied Chemistry. Applied Chemistry manuscripts should be restricted to corrosion of materials, environmental chemistry and water quality (pollution studies), physico-chemical properties of naturally ...

  2. Recent Advances in Bio-inorganic Chemistry

    Indian Academy of Sciences (India)

    Unknown

    Recent Advances in Bio-inorganic Chemistry. FOREWORD. Bio-inorganic chemistry has developed rapidly in recent years. A number of laboratories in India have made significant contributions to this area. The motivation in bringing out this special issue on Bio-inorganic. Chemistry is to highlight the recent work emerging ...

  3. Diversity and Periodicity: An Inorganic Chemistry Module.

    Science.gov (United States)

    Huheey, James

    This book is one in a series of Interdisciplinary Approaches to Chemistry (IAC) designed to help students discover that chemistry is a lively science and actively used to pursue solutions to the important problems of today. It is expected for students to see how chemistry takes place continuously all around and to readily understand the daily…

  4. Undergraduate Chemistry Education: A Workshop Summary

    Science.gov (United States)

    Sawyer, Keegan; Alper, Joe

    2014-01-01

    "Undergraduate Chemistry Education" is the summary of a workshop convened in May 2013 by the Chemical Science Roundtable of the National Research Council to explore the current state of undergraduate chemistry education. Research and innovation in undergraduate chemistry education has been done for many years, and one goal of this…

  5. Modern Analytical Chemistry in the Contemporary World

    Science.gov (United States)

    Šíma, Jan

    2016-01-01

    Students not familiar with chemistry tend to misinterpret analytical chemistry as some kind of the sorcery where analytical chemists working as modern wizards handle magical black boxes able to provide fascinating results. However, this approach is evidently improper and misleading. Therefore, the position of modern analytical chemistry among…

  6. Green Chemistry Techniques for Gold Nanoparticles Synthesis

    Science.gov (United States)

    Cannavino, Sarah A.; King, Christy A.; Ferrara, Davon W.

    Gold nanoparticles (AuNPs) are often utilized in many technological and research applications ranging from the detection of tumors, molecular and biological sensors, and as nanoantennas to probe physical processes. As these applications move from the research laboratory to industrial settings, there is a need to develop efficient and sustainable synthesis techniques. Recent research has shown that several food products and beverages containing polyphenols, a common antioxidant, can be used as reducing agents in the synthesis of AuNPs in solution. In this study, we explore a variety of products to determine which allow for the most reproducible solution of nanoparticles based on the size and shapes of particles present. We analyzed the AuNPs solutions using extinction spectroscopy and atomic force microscopy. We also develop a laboratory activity to introduce introductory chemistry and physics students to AuNP synthesis techniques and analysis.

  7. NATO Advanced Study Institute on Fundamental and Technological Aspects of Organo-f-Element Chemistry

    CERN Document Server

    Fragalà, Ignazio

    1985-01-01

    The past decade has seen a dramatic acceleration of activity and interest in phenomena surrounding lanthanide and actinide organo­ metallic compounds. Around the world, active research in organo-f­ element synthesis, chemistry, catalysis, crystallography, and quantum chemistry is in progress. This activity has spanned a remarkably wide range of disciplines, from synthetic/mechanistic inorganic and organic chemistry to radiochemistry, catalytic chemistry, spectroscopy (vibra­ tional, optical, magnetic resonance, photoelectron, Mossbauer), X-ray and neutron diffraction structural analysis, as well as to crystal field and molecular orbital theoretical studies at the interface of chemistry and physics. These investigations have been motivated both by fundamental and applied goals. The evidence that f-element organo­ metallic compounds have unique chemical and physical properties which cannot be duplicated by organometallic compounds of d-block elements has suggested many new areas of endeavor and application....

  8. Atmospheric Chemistry Over Southern Africa

    Science.gov (United States)

    Gatebe, Charles K.; Levy, Robert C.; Thompson, Anne M.

    2011-01-01

    During the southern African dry season, regional haze from mixed industrial pollution, biomass burning aerosol and gases from domestic and grassland fires, and biogenic sources from plants and soils is worsened by a semi-permanent atmosphere gyre over the subcontinent. These factors were a driver of several major international field campaigns in the 1990s and early 2000s, and attracted many scientists to the region. Some researchers were interested in understanding fundamental processes governing chemistry of the atmosphere and interaction with climate change. Others found favorable conditions for evaluating satellite-derived measurements of atmospheric properties and a changing land surface. With that background in mind a workshop on atmospheric chemistry was held in South Africa. Sponsored by the International Commission for Atmospheric Chemistry and Global Pollution (ICACGP; http://www.icacgp.org/), the workshop received generous support from the South African power utility, Eskom, and the Climatology Research Group of the University of the Witwatersrand, Johannesburg, South Africa. The purpose of the workshop was to review some earlier findings as well as more recent findings on southern African climate vulnerability, chemical changes due to urbanization, land-use modification, and how these factors interact. Originally proposed by John Burrows, president of ICACGP, the workshop was the first ICACGP regional workshop to study the interaction of air pollution with global chemical and climate change. Organized locally by the University of the Witwatersrand, the workshop attracted more than 60 delegates from South Africa, Mozambique, Botswana, Zimbabwe, France, Germany, Canada, and the United States. More than 30 presentations were given, exploring both retrospective and prospective aspects of the science. In several talks, attention was focused on southern African chemistry, atmospheric pollution monitoring, and climate processes as they were studied in the field

  9. 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.

  10. Range Selection and Median

    DEFF Research Database (Denmark)

    Jørgensen, Allan Grønlund; Larsen, Kasper Green

    2011-01-01

    that supports queries in constant time, needs n1+ (1) space. For data structures that uses n logO(1) n space this matches the best known upper bound. Additionally, we present a linear space data structure that supports range selection queries in O(log k= log log n + log log n) time. Finally, we prove that any...

  11. Electric vehicles: Driving range

    Science.gov (United States)

    Kempton, Willett

    2016-09-01

    For uptake of electric vehicles to increase, consumers' driving-range needs must be fulfilled. Analysis of the driving patterns of personal vehicles in the US now shows that today's electric vehicles can meet all travel needs on almost 90% of days from a single overnight charge.

  12. The slow birth of green chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Amato, I.

    1993-03-12

    Mainstream chemistry is beginning to look at environmental chemistry as an important solution to environmental problems. This can include research into developing cleaner-burning liquid fuels, cleaning up oil spills, or developing better process methods which engender less pollution, as opposed to previous practices of detecting pollutants without preventing their release to begin with. This article discusses the progress of this chemistry discipline, describes some of the ongoing research, and describes the future for environmental chemistry. An impetus for future growth will be generational change, as young scientists in training are beginning to push faculities into creating programs for environmental chemistry.

  13. Solid state chemistry and its applications

    CERN Document Server

    West, Anthony R

    2013-01-01

    Solid State Chemistry and its Applications, 2nd Edition: Student Edition is an extensive update and sequel to the bestselling textbook Basic Solid State Chemistry, the classic text for undergraduate teaching in solid state chemistry worldwide. Solid state chemistry lies at the heart of many significant scientific advances from recent decades, including the discovery of high-temperature superconductors, new forms of carbon and countless other developments in the synthesis, characterisation and applications of inorganic materials. Looking forward, solid state chemistry will be crucial for the

  14. Ideograms for Physics and Chemistry

    CERN Document Server

    García-Risueño, Pablo; Verges, Natalia

    2016-01-01

    Ideograms (symbols that represent a word or idea) have great communicative value. They refer to concepts in a simple manner, easing the understanding of related ideas. Moreover, ideograms can simplify the often cumbersome notation used in the fields of Physics and physical Chemistry. Nonetheless only a few specific ideograms for these fields have been defined to date. In this work we propose that the scientific community follows the example of Mathematics -as well as that of oriental languages- and bestows a more important role upon ideograms. To support this thesis we propose ideograms for essential concepts in Physics and Chemistry. They are designed to be intuitive, and their goal is to make equations easier to read and understand. Our symbols are included in a publicly available Latex package (svrsymbols).

  15. Ideograms for Physics and Chemistry

    Science.gov (United States)

    García Risueño, Pablo; Syropoulos, Apostolos; Vergés, Natàlia

    2016-12-01

    Ideograms (symbols that represent a word or idea) have great communicative value. They refer to concepts in a simple manner, easing the understanding of related ideas. Moreover, ideograms can simplify the often cumbersome notation used in the fields of Physics and physical Chemistry. Nonetheless only a few ideograms- like and - have been defined to date. In this work we propose that the scientific community follows the example of Mathematics—as well as that of oriental languages—and bestows a more important role upon ideograms. To support this thesis we propose ideograms for essential concepts in Physics and Chemistry. They are designed to be intuitive, and their goal is to make equations easier to read and understand. Our symbols are included in a publicly available [InlineEquation not available: see fulltext.]package ( svrsymbols).

  16. Green chemistry, biofuels, and biorefinery.

    Science.gov (United States)

    Clark, James H; Luque, Rafael; Matharu, Avtar S

    2012-01-01

    In the current climate of several interrelated impending global crises, namely, climate change, chemicals, energy, and oil, the impact of green chemistry with respect to chemicals and biofuels generated from within a holistic concept of a biorefinery is discussed. Green chemistry provides unique opportunities for innovation via product substitution, new feedstock generation, catalysis in aqueous media, utilization of microwaves, and scope for alternative or natural solvents. The potential of utilizing waste as a new resource and the development of integrated facilities producing multiple products from biomass is discussed under the guise of biorefineries. Biofuels are discussed in depth, as they not only provide fuel (energy) but are also a source of feedstock chemicals. In the future, the commercial success of biofuels commensurate with consumer demand will depend on the availability of new green (bio)chemical technologies capable of converting waste biomass to fuel in a context of a biorefinery.

  17. Combining supramolecular chemistry with biology.

    Science.gov (United States)

    Uhlenheuer, Dana A; Petkau, Katja; Brunsveld, Luc

    2010-08-01

    Supramolecular chemistry has primarily found its inspiration in biological molecules, such as proteins and lipids, and their interactions. Currently the supramolecular assembly of designed compounds can be controlled to great extent. This provides the opportunity to combine these synthetic supramolecular elements with biomolecules for the study of biological phenomena. This tutorial review focuses on the possibilities of the marriage of synthetic supramolecular architectures and biological systems. It highlights that synthetic supramolecular elements are for example ideal platforms for the recognition and modulation of proteins and cells. The unique features of synthetic supramolecular systems with control over size, shape, valency, and interaction strength allow the generation of structures fitting the demands to approach the biological problems at hand. Supramolecular chemistry has come full circle, studying the biology and its molecules which initially inspired its conception.

  18. [Research Advances in Postmortem Chemistry].

    Science.gov (United States)

    Han, Shun-qi; Qin, Zhi-qiang; Deng, Kai-fei; Zhang, Jian-hua; Liu, Ning-guo; Zou, Dong-hua; Li, Zheng-dong; Shao, Yu; Huang, Ping; Chen, Yi-jiu

    2015-08-01

    Postmortem chemistry is becoming more and more essential in routine forensic pathology and has made considerable progress over the past years. Biochemical analyses of vitreous humor, blood, urine and cerebrospinal fluid may provide important information in determining the cause of death or in elucidating forensic issues. Postmortem chemistry may be essential for the determination of cause of death when morphological methods (diabetes mellitus, alcoholic ketoacidosis and electrolytic disorders) cannot detect the pathophysiological changes involved in the death process. It can also provide many information in other forensic situations, including myocardial ischemia, sepsis, inflammation, infection, anaphylaxis and hormonal disturbances. The most recent relevant research advances on glucose metabolism, liver function, cardiac function, renal function, sepsis, inflammation, infection, anaphylaxis and hormonal aspect are hereby reviewed.

  19. Wood products and green chemistry

    OpenAIRE

    Pizzi, Antonio

    2016-01-01

    International audience; Key message Green chemistry for and from wood has developed numerous industrial products, namely biosourced, green wood adhesives and preservatives, foams, composite matrices, laminates, hard and flexible plastics, flexible films, and abrasive grinding discs, and their number is still growing.IntroductionThis review addresses (1) the elimination of toxic aldehydes from the most common wood panel adhesive, the one based on urea, itself a natural product, (2) biosourced ...

  20. Patterns in clinical chemistry requests

    OpenAIRE

    Hemel, Jan B.; Hindriks, Frans R.; van der Voet, Hilko; Rijnveld, Leo R.

    1989-01-01

    For each patient sample that is presented to the clinical chemistry laboratory a combination of various tests can be requested. This combination or profile will depend on the condition of the patient, and hence also on the requesting hospital department. Several techniques were applied to detect and describe patterns in tests requested by the cardiology, hepatology and nephrology sections of the out-patient's Department for Internal Medicine. Comparison of the frequencies of ordering the test...

  1. Chemistry of the outer planets

    Science.gov (United States)

    Scattergood, Thomas W.

    1992-05-01

    Various aspects were studied of past or present chemistry in the atmospheres of the outer planets and their satellites using lab simulations. Three areas were studied: (1) organic chemistry induced by kinetically hot hydrogen atoms in the region of Jupiter's atmosphere containing the ammonia cirrus clouds; (2) the conversion of NH3 into N2 by plasmas associated with entry of meteors and other objects into the atmosphere of early Titan; and (3) the synthesis of simple hydrocarbons and HCN by lightning in mixtures containing N2, CH4, and NH3 representing the atmospheres of Titan and the outer planets. The results showed that: (1) hot H2 atoms formed from the photodissociation of NH3 in Jupiter's atmosphere could account for some of the atmospheric chemistry in the ammonia cirrus cloud region; (2) the thermalization of hot H2 atoms in atmospheres predominated by molecular H is not as rapid as predicted by elastic collision theory; (3) the net quantum loss of NH3 in the presence of a 200 fold excess of H2 is 0.02, much higher than was expected from the amount of H2 present; (4) the conversion of NH3 into N2 in plasmas associated with infalling meteors is very efficient and rapid, and could account for most of the N2 present on Titan; (5) the yields of C2H2 and HCN from lightning induced chemistry in mixtures of CH4 and N2 is consistent with quenched thermodynamic models of the discharge core; and (6) photolysis induced by the UV light emitted by the gases in the hot plasmas may account for some, if not most, of the excess production of C2H6 and the more complex hydrocarbons.

  2. Handbook of computational quantum chemistry

    CERN Document Server

    Cook, David B

    2005-01-01

    Quantum chemistry forms the basis of molecular modeling, a tool widely used to obtain important chemical information and visual images of molecular systems. Recent advances in computing have resulted in considerable developments in molecular modeling, and these developments have led to significant achievements in the design and synthesis of drugs and catalysts. This comprehensive text provides upper-level undergraduates and graduate students with an introduction to the implementation of quantum ideas in molecular modeling, exploring practical applications alongside theoretical explanations.Wri

  3. Phenolics: From Chemistry to Biology

    OpenAIRE

    David M. Pereira; Patrícia Valentão; José A. Pereira; Paula B. Andrade

    2009-01-01

    In recent years, few classes of natural products have received as much attention as phenolics and polyphenols. This special issue of Molecules, “Phenolics and Polyphenolics”, is a remarkable confirmation of this trend. Several aspects related to phenolics chemistry, comprising the several classes, will be discussed. In addition, the increasing interest in phenolics’ biological activities is covered, and several works addressing this matter are referred.

  4. IN-PACKAGE CHEMISTRY ABSTRACTION

    Energy Technology Data Exchange (ETDEWEB)

    E. Thomas

    2005-07-14

    This report was developed in accordance with the requirements in ''Technical Work Plan for Postclosure Waste Form Modeling'' (BSC 2005 [DIRS 173246]). The purpose of the in-package chemistry model is to predict the bulk chemistry inside of a breached waste package and to provide simplified expressions of that chemistry as a function of time after breach to Total Systems Performance Assessment for the License Application (TSPA-LA). The scope of this report is to describe the development and validation of the in-package chemistry model. The in-package model is a combination of two models, a batch reactor model, which uses the EQ3/6 geochemistry-modeling tool, and a surface complexation model, which is applied to the results of the batch reactor model. The batch reactor model considers chemical interactions of water with the waste package materials, and the waste form for commercial spent nuclear fuel (CSNF) waste packages and codisposed (CDSP) waste packages containing high-level waste glass (HLWG) and DOE spent fuel. The surface complexation model includes the impact of fluid-surface interactions (i.e., surface complexation) on the resulting fluid composition. The model examines two types of water influx: (1) the condensation of water vapor diffusing into the waste package, and (2) seepage water entering the waste package as a liquid from the drift. (1) Vapor-Influx Case: The condensation of vapor onto the waste package internals is simulated as pure H{sub 2}O and enters at a rate determined by the water vapor pressure for representative temperature and relative humidity conditions. (2) Liquid-Influx Case: The water entering a waste package from the drift is simulated as typical groundwater and enters at a rate determined by the amount of seepage available to flow through openings in a breached waste package.

  5. Recent advances in cholesterol chemistry.

    Science.gov (United States)

    Morzycki, Jacek W

    2014-05-01

    This review article presents advances in cholesterol chemistry since 2000. Various transformations (chemical, enzymatic, electrochemical, etc.) of cholesterol are presented. A special emphasis is given to cholesterol oxidation reactions, but also substitution of the 3β-hydroxyl group, addition to the C5-C6 double bond, C-H functionalization, and C-C bond forming reactions are discussed. Copyright © 2014 Elsevier Inc. All rights reserved.

  6. POLYSULFANE AND CHEMISTRY OF POLISELANOS

    OpenAIRE

    Ceroni G., Mario; Facultad de Química e Ingeniería Química, Departamento de Química Inorgánica,Universidad Nacional Mayor de San Marcos,Lima,Perú.

    2014-01-01

    This article is a literature review of the chemistry and poliselanos polysulfane. It describes the importance of these compounds, the method of production and reactivity. Este artículo es una revisión bibliográfica de la química de los polisulfanos y poliselanos. Se describe la importancia de estos compuestos, el modo de obtención y la reactividad.

  7. Materials Chemistry of Nanoultrasonic Biomedicine.

    Science.gov (United States)

    Tang, Hailin; Zheng, Yuanyi; Chen, Yu

    2017-03-01

    As a special cross-disciplinary research frontier, nanoultrasonic biomedicine refers to the design and synthesis of nanomaterials to solve some critical issues of ultrasound (US)-based biomedicine. The concept of nanoultrasonic biomedicine can also overcome the drawbacks of traditional microbubbles and promote the generation of novel US-based contrast agents or synergistic agents for US theranostics. Here, we discuss the recent developments of material chemistry in advancing the nanoultrasonic biomedicine for diverse US-based bio-applications. We initially introduce the design principles of novel nanoplatforms for serving the nanoultrasonic biomedicine, from the viewpoint of synthetic material chemistry. Based on these principles and diverse US-based bio-application backgrounds, the representative proof-of-concept paradigms on this topic are clarified in detail, including nanodroplet vaporization for intelligent/responsive US imaging, multifunctional nano-contrast agents for US-based multi-modality imaging, activatable synergistic agents for US-based therapy, US-triggered on-demand drug releasing, US-enhanced gene transfection, US-based synergistic therapy on combating the cancer and potential toxicity issue of screening various nanosystems suitable for nanoultrasonic biomedicine. It is highly expected that this novel nanoultrasonic biomedicine and corresponding high performance in US imaging and therapy can significantly promote the generation of new sub-discipline of US-based biomedicine by rationally integrating material chemistry and theranostic nanomedicine with clinical US-based biomedicine. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Green chemistry; La chimie verte

    Energy Technology Data Exchange (ETDEWEB)

    Colonna, P. [Institut National de la Recherche Agronomique, Dept. Caracterisation et Elaboration des Produits, 78 - Versailles (France)

    2006-07-01

    The depletion of world fossil fuel reserves and the involvement of greenhouse gases in the global warming has led to change the industrial and energy policies of most developed countries. The goal is now to reserve petroleum to the uses where it cannot be substituted, to implement renewable raw materials obtained from plants cultivation, and to consider the biodegradability of molecules and of manufactured objects by integrating the lifetime concept in their expected cycle of use. The green chemistry includes the design, development and elaboration of chemical products and processes with the aim of reducing or eliminating the use and generation of harmful compounds for the health and the environment, by adapting the present day operation modes of the chemical industry to the larger framework of the sustainable development. In addition to biofuels, this book reviews the applications of green chemistry in the different industrial processes in concern. Part 1 presents the diversity of the molecules coming from renewable carbon, in particular lignocellulose and the biotechnological processes. Part 2 is devoted to materials and treats of the overall available technological solutions. Part 3 focusses on functional molecules and chemical intermediates, in particular in sugar- and fats-chemistry. Part 4 treats of biofuels under the aspects of their production and use in today's technologies. The last part deals with the global approaches at the environmental and agricultural levels. (J.S.)

  9. Efficient Functionalization of Oxide-Free Silicon(111) Surfaces: Thiol–yne versus Thiol–ene Click Chemistry

    NARCIS (Netherlands)

    Bhairamadgi, N.S.; Gangarapu, S.; Caipa Campos, M.A.; Paulusse, Jos Marie Johannes; van Rijn, C.J.M.; Zuilhof, H.

    2013-01-01

    Thiol-yne click (TYC) chemistry was utilized as a copper-free click reaction for the modification of alkyne-terminated monolayers on oxide-free Si(111) surfaces, and the results were compared with the analogous thiol–ene click (TEC) chemistry. A wide range of thiols such as

  10. In-Package Chemistry Abstraction

    Energy Technology Data Exchange (ETDEWEB)

    E. Thomas

    2004-11-09

    This report was developed in accordance with the requirements in ''Technical Work Plan for: Regulatory Integration Modeling and Analysis of the Waste Form and Waste Package'' (BSC 2004 [DIRS 171583]). The purpose of the in-package chemistry model is to predict the bulk chemistry inside of a breached waste package and to provide simplified expressions of that chemistry as function of time after breach to Total Systems Performance Assessment for the License Application (TSPA-LA). The scope of this report is to describe the development and validation of the in-package chemistry model. The in-package model is a combination of two models, a batch reactor model that uses the EQ3/6 geochemistry-modeling tool, and a surface complexation model that is applied to the results of the batch reactor model. The batch reactor model considers chemical interactions of water with the waste package materials and the waste form for commercial spent nuclear fuel (CSNF) waste packages and codisposed waste packages that contain both high-level waste glass (HLWG) and DOE spent fuel. The surface complexation model includes the impact of fluid-surface interactions (i.e., surface complexation) on the resulting fluid composition. The model examines two types of water influx: (1) the condensation of water vapor that diffuses into the waste package, and (2) seepage water that enters the waste package from the drift as a liquid. (1) Vapor Influx Case: The condensation of vapor onto the waste package internals is simulated as pure H2O and enters at a rate determined by the water vapor pressure for representative temperature and relative humidity conditions. (2) Water Influx Case: The water entering a waste package from the drift is simulated as typical groundwater and enters at a rate determined by the amount of seepage available to flow through openings in a breached waste package. TSPA-LA uses the vapor influx case for the nominal scenario for simulations where the waste

  11. 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.

  12. Microscale chemistry technology exchange at Argonne National Laboratory - east.

    Energy Technology Data Exchange (ETDEWEB)

    Pausma, R.

    1998-06-04

    The Division of Educational Programs (DEP) at Argonne National Laboratory-East interacts with the education community at all levels to improve science and mathematics education and to provide resources to instructors of science and mathematics. DEP conducts a wide range of educational programs and has established an enormous audience of teachers, both in the Chicago area and nationally. DEP has brought microscale chemistry to the attention of this huge audience. This effort has been supported by the U.S. Department of Energy through the Environmental Management Operations organization within Argonne. Microscale chemistry is a teaching methodology wherein laboratory chemistry training is provided to students while utilizing very small amounts of reagents and correspondingly small apparatus. The techniques enable a school to reduce significantly the cost of reagents, the cost of waste disposal and the dangers associated with the manipulation of chemicals. The cost reductions are achieved while still providing the students with the hands-on laboratory experience that is vital to students who might choose to pursue careers in the sciences. Many universities and colleges have already begun to switch from macroscale to microscale chemistry in their educational laboratories. The introduction of these techniques at the secondary education level will lead to freshman being better prepared for the type of experimentation that they will encounter in college.

  13. A framework for expanding aqueous chemistry in the ...

    Science.gov (United States)

    This paper describes the development and implementation of an extendable aqueous-phase chemistry option (AQCHEM − KMT(I)) for the Community Multiscale Air Quality (CMAQ) modeling system, version 5.1. Here, the Kinetic PreProcessor (KPP), version 2.2.3, is used to generate a Rosenbrock solver (Rodas3) to integrate the stiff system of ordinary differential equations (ODEs) that describe the mass transfer, chemical kinetics, and scavenging processes of CMAQ clouds. CMAQ's standard cloud chemistry module (AQCHEM) is structurally limited to the treatment of a simple chemical mechanism. This work advances our ability to test and implement more sophisticated aqueous chemical mechanisms in CMAQ and further investigate the impacts of microphysical parameters on cloud chemistry. Box model cloud chemistry simulations were performed to choose efficient solver and tolerance settings, evaluate the implementation of the KPP solver, and assess the direct impacts of alternative solver and kinetic mass transfer on predicted concentrations for a range of scenarios. Month-long CMAQ simulations for winter and summer periods over the US reveal the changes in model predictions due to these cloud module updates within the full chemical transport model. While monthly average CMAQ predictions are not drastically altered between AQCHEM and AQCHEM − KMT, hourly concentration differences can be significant. With added in-cloud secondary organic aerosol (SOA) formation from bio

  14. Long-range antigravity

    Energy Technology Data Exchange (ETDEWEB)

    Macrae, K.I.; Riegert, R.J. (Maryland Univ., College Park (USA). Center for Theoretical Physics)

    1984-10-01

    We consider a theory in which fermionic matter interacts via long-range scalar, vector and tensor fields. In order not to be in conflict with experiment, the scalar and vector couplings for a given fermion must be equal, as is natural in a dimensionally reduced model. Assuming that the Sun is not approximately neutral with respect to these new scalar-vector charges, and if the couplings saturate the experimental bounds, then their strength can be comparable to that of gravity. Scalar-vector fields of this strength can compensate for a solar quadrupole moment contribution to Mercury's anomalous perihelion precession.

  15. Chemistry and Materials Science Strategic Plan

    Energy Technology Data Exchange (ETDEWEB)

    Rhodie, K B; Mailhiot, C; Eaglesham, D; Hartmann-Siantar, C L; Turpin, L S; Allen, P G

    2004-04-21

    Lawrence Livermore National Laboratory's mission is as clear today as it was in 1952 when the Laboratory was founded--to ensure our country's national security and the safety and reliability of its nuclear deterrent. As a laboratory pursuing applied science in the national interest, we strive to accomplish our mission through excellence in science and technology. We do this while developing and implementing sound and robust business practices in an environment that emphasizes security and ensures our safety and the safety of the community around us. Our mission as a directorate derives directly from the Laboratory's charter. When I accepted the assignment of Associate Director for Chemistry and Materials Science (CMS), I talked to you about the need for strategic balance and excellence in all our endeavors. We also discussed how to take the directorate to the next level. The long-range CMS strategic plan presented here was developed with this purpose in mind. It also aligns with the Lab's institutional long-range science and technology plan and its 10-year facilities and infrastructure site plan. The plan is aimed at ensuring that we fulfill our directorate's two governing principles: (1) delivering on our commitments to Laboratory programs and sponsors, and (2) anticipating change and capitalizing on opportunities through innovation in science and technology. This will require us to attain a new level of creativity, agility, and flexibility as we move forward. Moreover, a new level of engagement in partnerships with other directorates across the Laboratory as well as with universities and other national labs will also be required. The group of managers and staff that I chartered to build a strategic plan identified four organizing themes that define our directorate's work and unite our staff with a set of common goals. The plan presented here explains how we will proceed in each of these four theme areas: (1) Materials properties and

  16. Online Sorted Range Reporting

    DEFF Research Database (Denmark)

    Brodal, Gerth Stølting; Fagerberg, Rolf; Greve, Mark

    2009-01-01

    We study the following one-dimensional range reporting problem: On an arrayA of n elements, support queries that given two indices i ≤ j and an integerk report the k smallest elements in the subarray A[i..j] in sorted order. We present a data structure in the RAM model supporting such queries...... in optimal O(k) time. The structure uses O(n) words of space and can be constructed in O(n logn) time. The data structure can be extended to solve the online version of the problem, where the elements in A[i..j] are reported one-by-one in sorted order, in O(1) worst-case time per element. The problem...... is motivated by (and is a generalization of) a problem with applications in search engines: On a tree where leaves have associated rank values, report the highest ranked leaves in a given subtree. Finally, the problem studied generalizes the classic range minimum query (RMQ) problem on arrays....

  17. Nanoparticle growth by particle-phase chemistry

    Directory of Open Access Journals (Sweden)

    M. J. Apsokardu

    2018-02-01

    Full Text Available The ability of particle-phase chemistry to alter the molecular composition and enhance the growth rate of nanoparticles in the 2–100 nm diameter range is investigated through the use of a kinetic growth model. The molecular components included are sulfuric acid, ammonia, water, a non-volatile organic compound, and a semi-volatile organic compound. Molecular composition and growth rate are compared for particles that grow by partitioning alone vs. those that grow by a combination of partitioning and an accretion reaction in the particle phase between two organic molecules. Particle-phase chemistry causes a change in molecular composition that is particle diameter dependent, and when the reaction involves semi-volatile molecules, the particles grow faster than by partitioning alone. These effects are most pronounced for particles larger than about 20 nm in diameter. The modeling results provide a fundamental basis for understanding recent experimental measurements of the molecular composition of secondary organic aerosol showing that accretion reaction product formation increases linearly with increasing aerosol volume-to-surface-area. They also allow initial estimates of the reaction rate constants for these systems. For secondary aerosol produced by either OH oxidation of the cyclic dimethylsiloxane (D5 or ozonolysis of β-pinene, oligomerization rate constants on the order of 10−3 to 10−1 M−1 s−1 are needed to explain the experimental results. These values are consistent with previously measured rate constants for reactions of hydroperoxides and/or peroxyacids in the condensed phase.

  18. Lightning detection and ranging

    Science.gov (United States)

    Lennon, C. L.; Poehler, H. A.

    1982-01-01

    A lightning detector and ranging (LDAR) system developed at the Kennedy Space Center and recently transferred to Wallops Island is described. The system detects pulsed VHF signals due to electrical discharges occurring in a thunderstorm by means of 56-75 MHz receivers located at the hub and at the tips of 8 km radial lines. Incoming signals are transmitted by wideband links to a central computing facility which processes the times of arrival, using two independent calculations to determine position in order to guard against false data. The results are plotted on a CRT display, and an example of a thunderstorm lightning strike detection near Kennedy Space Center is outlined. The LDAR correctly identified potential ground strike zones and additionally provided a high correlation between updrafts and ground strikes.

  19. Green chemistry of carbon nanomaterials.

    Science.gov (United States)

    Basiuk, Elena V; Basiuk, Vladimir A

    2014-01-01

    The global trend of looking for more ecologically friendly, "green" techniques manifested itself in the chemistry of carbon nanomaterials. The main principles of green chemistry emphasize how important it is to avoid the use, or at least to reduce the consumption, of organic solvents for a chemical process. And it is precisely this aspect that was systematically addressed and emphasized by our research group since the very beginning of our work on the chemistry of carbon nanomaterials in early 2000s. The present review focuses on the results obtained to date on solvent-free techniques for (mainly covalent) functionalization of fullerene C60, single-walled and multi-walled carbon nanotubes (SWNTs and MWNTs, respectively), as well as nanodiamonds (NDs). We designed a series of simple and fast functionalization protocols based on thermally activated reactions with chemical compounds stable and volatile at 150-200 degrees C under reduced pressure, when not only the reactions take place at a high rate, but also excess reagents are spontaneously removed from the functionalized material, thus making its purification unnecessary. The main two classes of reagents are organic amines and thiols, including bifunctional ones, which can be used in conjunction with different forms of nanocarbons. The resulting chemical processes comprise nucleophilic addition of amines and thiols to fullerene C60 and to defect sites of pristine MWNTs, as well as direct amidation of carboxylic groups of oxidized nanotubes (mainly SWNTs) and ND. In the case of bifunctional amines and thiols, reactions of the second functional group can give rise to cross-linking effects, or be employed for further derivatization steps.

  20. Polyoxometalates: from inorganic chemistry to materials science.

    Science.gov (United States)

    Casañ-Pastor, Nieves; Gómez-Romero, Pedro

    2004-05-01

    Polyoxometalates have been traditionally the subject of study of molecular inorganic chemistry. Yet, these polynuclear molecules, reminiscent of oxide clusters, present a wide range of structures and with them ideal frameworks for the deployment of a plethora of useful magnetic, electroionic, catalytic, bioactive and photochemical properties. With this in mind, a new trend towards the application of these remarkable species in materials science is beginning to develop. In this review we analyze this trend and discuss two main lines of thought for the application of polyoxometalates as materials. On the one hand, there is their use as clusters with inherently useful properties on themselves, a line which has produced fundamental studies of their magnetic, electronic or photoelectrochemical properties and has shown these clusters as models for quantum-sized oxides. On the other hand, the encapsulation or integration of polyoxometalates into organic, polymeric or inorganic matrices or substrates opens a whole new field within the area of hybrid materials for harnessing the multifunctional properties of these versatile species in a wide variety of applications, ranging from catalysis to energy storage to biomedicine.

  1. Computing protein infrared spectroscopy with quantum chemistry.

    Science.gov (United States)

    Besley, Nicholas A

    2007-12-15

    Quantum chemistry is a field of science that has undergone unprecedented advances in the last 50 years. From the pioneering work of Boys in the 1950s, quantum chemistry has evolved from being regarded as a specialized and esoteric discipline to a widely used tool that underpins much of the current research in chemistry today. This achievement was recognized with the award of the 1998 Nobel Prize in Chemistry to John Pople and Walter Kohn. As the new millennium unfolds, quantum chemistry stands at the forefront of an exciting new era. Quantitative calculations on systems of the magnitude of proteins are becoming a realistic possibility, an achievement that would have been unimaginable to the early pioneers of quantum chemistry. In this article we will describe ongoing work towards this goal, focusing on the calculation of protein infrared amide bands directly with quantum chemical methods.

  2. Physical chemistry a very short introduction

    CERN Document Server

    Atkins, Peter

    2014-01-01

    With the development of a variety of exciting new areas of research involving computational chemistry, nano- and smart materials, and applications of the recently discovered graphene, there can be no doubt that physical chemistry is a vitally important field. It is also perceived as the most daunting branch of chemistry, being necessarily grounded in physics and mathematics and drawing as it does on quantum mechanics, thermodynamics, and statistical thermodynamics. With his typical clarity and hardly a formula in sight, Peter Atkins' Very Short Introduction explores the contributions physical chemistry has made to all branches of chemistry. Providing insight into its central concepts Atkins reveals the cultural contributions physical chemistry has made to our understanding of the natural world.

  3. Sulfur Chemistry in Combustion I

    DEFF Research Database (Denmark)

    Johnsson, Jan Erik; Glarborg, Peter

    2000-01-01

    Most fossil fuels contain sulphur and also biofuels and household waste have a sulphur content. As a consequence sulphur species will often be present in combustion processes. In this paper the fate and influence of fuel sulphur species in combustion will be treated. First a description...... of the sulphur compounds in fossil fuels and the possibilities to remove them will be given. Then the combustion of sulphur species and their influence on the combustion chemistry and especially on the CO oxidation and the NOx formation will be described. Finally the in-situ removal of sulphur in the combustion...

  4. THE ADVANCED CHEMISTRY BASINS PROJECT

    Energy Technology Data Exchange (ETDEWEB)

    William Goddard; Peter Meulbroek; Yongchun Tang; Lawrence Cathles III

    2004-04-05

    In the next decades, oil exploration by majors and independents will increasingly be in remote, inaccessible areas, or in areas where there has been extensive shallow exploration but deeper exploration potential may remain; areas where the collection of data is expensive, difficult, or even impossible, and where the most efficient use of existing data can drive the economics of the target. The ability to read hydrocarbon chemistry in terms of subsurface migration processes by relating it to the evolution of the basin and fluid migration is perhaps the single technological capability that could most improve our ability to explore effectively because it would allow us to use a vast store of existing or easily collected chemical data to determine the major migration pathways in a basin and to determine if there is deep exploration potential. To this end a the DOE funded a joint effort between California Institute of Technology, Cornell University, and GeoGroup Inc. to assemble a representative set of maturity and maturation kinetic models and develop an advanced basin model able to predict the chemistry of hydrocarbons in a basin from this input data. The four year project is now completed and has produced set of public domain maturity indicator and maturation kinetic data set, an oil chemistry and flash calculation tool operable under Excel, and a user friendly, graphically intuitive basin model that uses this data and flash tool, operates on a PC, and simulates hydrocarbon generation and migration and the chemical changes that can occur during migration (such as phase separation and gas washing). The DOE Advanced Chemistry Basin Model includes a number of new methods that represent advances over current technology. The model is built around the concept of handling arbitrarily detailed chemical composition of fluids in a robust finite-element 2-D grid. There are three themes on which the model focuses: chemical kinetic and equilibrium reaction parameters, chemical

  5. The Birth of Modern Chemistry

    OpenAIRE

    Rayner, Thomas Allan; Mackevica, Aiga

    2009-01-01

    Alchemy was a science practiced for more than two millennia up till the end of 18th century when it was replaced by modern chemistry, which is practiced up till this very day. The purpose of this report is to look into this shift and investigate whether this shift can be classified as a paradigm shift according to the famous philosopher Thomas Kuhn, who came up with a theory on the structure of scientific revolutions. In order to come to draw any kind of conclusions, the report...

  6. Protostellar accretion traced with chemistry

    DEFF Research Database (Denmark)

    Frimann, Søren; Jørgensen, Jes Kristian; Padoan, Paolo

    2016-01-01

    used foranalysing the observations. Methods: Simple freeze-out andsublimation chemistry is added to the simulation, and syntheticC18O line cubes are created for a large number of simulatedprotostars. The spatial extent of C18O is measured for thesimulated protostars and compared directly to a sample...... by infall from the larger scales of the molecular cloud, anddo not include any disk physics. The discrepancy between simulation andobservations is taken as support for the necessity of disks, even indeeply embedded objects, to produce episodic accretion events ofsufficient frequency and amplitude....

  7. Advances in high temperature chemistry

    CERN Document Server

    Eyring, Leroy

    1969-01-01

    Advances in High Temperature Chemistry, Volume 2 covers the advances in the knowledge of the high temperature behavior of materials and the complex and unfamiliar characteristics of matter at high temperature. The book discusses the dissociation energies and free energy functions of gaseous monoxides; the matrix-isolation technique applied to high temperature molecules; and the main features, the techniques for the production, detection, and diagnosis, and the applications of molecular beams in high temperatures. The text also describes the chemical research in streaming thermal plasmas, as w

  8. Photoredox Catalysis in Organic Chemistry

    Science.gov (United States)

    2016-01-01

    In recent years, photoredox catalysis has come to the forefront in organic chemistry as a powerful strategy for the activation of small molecules. In a general sense, these approaches rely on the ability of metal complexes and organic dyes to convert visible light into chemical energy by engaging in single-electron transfer with organic substrates, thereby generating reactive intermediates. In this Perspective, we highlight the unique ability of photoredox catalysis to expedite the development of completely new reaction mechanisms, with particular emphasis placed on multicatalytic strategies that enable the construction of challenging carbon–carbon and carbon–heteroatom bonds. PMID:27477076

  9. Continuous Chemistry in Ice Cores

    DEFF Research Database (Denmark)

    Kjær, Helle Astrid

    on parameters involved in the study of photolysis as a source of in situ CO2. The concentration of organic substances in Greenland ice is poorly known due to their low levels and the fact that only a few studies evaluate the concentrations of specific organic compounds. Light does not penetrate deep...... depth was found as a function of wavelength. Further, by computational chemistry hybrid density functional methods (DFT), the four most common conformers of pyruvic acid were investigated in both gas, water and ice using the DFT model CAM-B3LYP with dielectric medium methods. A de rease of the energy...

  10. Nuclear techniques in analytical chemistry

    CERN Document Server

    Moses, Alfred J; Gordon, L

    1964-01-01

    Nuclear Techniques in Analytical Chemistry discusses highly sensitive nuclear techniques that determine the micro- and macro-amounts or trace elements of materials. With the increasingly frequent demand for the chemical determination of trace amounts of elements in materials, the analytical chemist had to search for more sensitive methods of analysis. This book accustoms analytical chemists with nuclear techniques that possess the desired sensitivity and applicability at trace levels. The topics covered include safe handling of radioactivity; measurement of natural radioactivity; and neutron a

  11. Protostellar accretion traced with chemistry

    DEFF Research Database (Denmark)

    Frimann, Søren; Jørgensen, Jes Kristian; Dunham, Michael M.

    2017-01-01

    . Our aim is to characterise protostellar accretion histories towards individual sources by utilising sublimation and freeze-out chemistry of CO. Methods. A sample of 24 embedded protostars are observed with the Submillimeter Array (SMA) in context of the large program "Mass Assembly of Stellar Systems...... and their Evolution with the SMA" (MASSES). The size of the C18O-emitting region, where CO has sublimated into the gas-phase, is measured towards each source and compared to the expected size of the region given the current luminosity. The SMA observations also include 1.3 mm continuum data, which are used...

  12. Surface chemistry theory and applications

    CERN Document Server

    Bikerman, J J

    2013-01-01

    Surface Chemistry Theory and Applications focuses on liquid-gas, liquid-liquid, solid-gas, solid-liquid, and solid-solid surfaces. The book first offers information on liquid-gas surfaces, including surface tension, measurement of surface tension, rate of capillarity rise, capillary attraction, bubble pressure and pore size, and surface tension and temperature. The text then ponders on liquid-liquid and solid-gas surfaces. Discussions focus on surface energy of solids, surface roughness and cleanness, adsorption of gases and vapors, adsorption hysteresis, interfacial tension, and interfacial t

  13. Advances in electron transfer chemistry

    CERN Document Server

    Mariano, Patrick S

    1995-01-01

    Advances in Electron Transfer Chemistry, Volume 4 presents the reaction mechanisms involving the movement of single electrons. This book discusses the electron transfer reactions in organic, biochemical, organometallic, and excited state systems. Organized into four chapters, this volume begins with an overview of the photochemical behavior of two classes of sulfonium salt derivatives. This text then examines the parameters that control the efficiencies for radical ion pair formation. Other chapters consider the progress in the development of parameters that control the dynamics and reaction p

  14. Plasma chemistry for inorganic materials

    Science.gov (United States)

    Matsumoto, O.

    1980-01-01

    Practical application of plasma chemistry to the development of inorganic materials using both low temperature and warm plasmas are summarized. Topics cover: the surface nitrification and oxidation of metals; chemical vapor deposition; formation of minute oxide particles; the composition of oxides from chloride vapor; the composition of carbides and nitrides; freezing high temperature phases by plasma arc welding and plasma jet; use of plasma in the development of a substitute for petroleum; the production of silicon for use in solar cell batteries; and insulating the inner surface of nuclear fusion reactor walls.

  15. Protostellar accretion traced with chemistry

    DEFF Research Database (Denmark)

    Frimann, Søren; Jørgensen, Jes Kristian; Dunham, Michael M.

    2017-01-01

    Context. Understanding how accretion proceeds is a key question of star formation, with important implications for both the physical and chemical evolution of young stellar objects. In particular, very little is known about the accretion variability in the earliest stages of star formation. Aims....... Our aim is to characterise protostellar accretion histories towards individual sources by utilising sublimation and freeze-out chemistry of CO. Methods. A sample of 24 embedded protostars are observed with the Submillimeter Array (SMA) in context of the large program "Mass Assembly of Stellar Systems...

  16. Simplified Model for Reburning Chemistry

    DEFF Research Database (Denmark)

    Glarborg, Peter; Hansen, Stine

    2010-01-01

    In solid fuel flames, reburn-type reactions are often important for the concentrations of NOx in the near-burner region. To be able to model the nitrogen chemistry in these flames, it is necessary to have an adequate model for volatile/NO interactions. Simple models consisting of global steps...... or based on partial-equilibrium assumptions have limited predictive capabilities. Reburning models based on systematic reduction of a detailed chemical kinetic model offer a high accuracy but rely on input estimates of combustion intermediates, including free radicals. In the present work, an analytically...

  17. Eurobachelor in Chemistry - Bulgaria's Odds? [In Bulgarian

    Directory of Open Access Journals (Sweden)

    B.V. Toshev

    2008-12-01

    Full Text Available The Bachelor education in chemistry is presented in the Universities of Sofia, Plovdiv, Shumen and Blagoevgrad. The chemistry education in the University of Sofia has a long tradition. The paper examines the rules and criteria for obtaining the Eurobachelor label, developed by the European Chemistry Thematic Network (ECTN. The comparative analysis of the existing program with these European criteria shows that the eventual application of the University of Sofia for that label seems to be untimely at the present moment.

  18. Entropy driven chain effects on ligation chemistry

    OpenAIRE

    Pahnke, K.; Brandt, J.; Gryn'ova, G.; Lindner, P.; Schweins, R.; Schmidt, F.G.; Lederer, A; Coote, M.L.; Barner-Kowollik, C

    2015-01-01

    We report the investigation of fundamental entropic chain effects that enable the tuning of modular ligation chemistry – for example dynamic Diels–Alder (DA) reactions in materials applications – not only classically via the chemistry of the applied reaction sites, but also via the physical and steric properties of the molecules that are being joined. Having a substantial impact on the reaction equilibrium of the reversible ligation chemistry, these effects are important when tran...

  19. Mathematical methods for physical and analytical chemistry

    CERN Document Server

    Goodson, David Z

    2011-01-01

    Mathematical Methods for Physical and Analytical Chemistry presents mathematical and statistical methods to students of chemistry at the intermediate, post-calculus level. The content includes a review of general calculus; a review of numerical techniques often omitted from calculus courses, such as cubic splines and Newton's method; a detailed treatment of statistical methods for experimental data analysis; complex numbers; extrapolation; linear algebra; and differential equations. With numerous example problems and helpful anecdotes, this text gives chemistry students the mathematical

  20. Physical Chemistry Chemical Kinetics and Reaction Mechanism

    CERN Document Server

    Trimm, Harold H

    2011-01-01

    Physical chemistry covers diverse topics, from biochemistry to materials properties to the development of quantum computers. Physical chemistry applies physics and math to problems that interest chemists, biologists, and engineers. Physical chemists use theoretical constructs and mathematical computations to understand chemical properties and describe the behavior of molecular and condensed matter. Their work involves manipulations of data as well as materials. Physical chemistry entails extensive work with sophisticated instrumentation and equipment as well as state-of-the-art computers. This

  1. Teaching social responsibility in analytical chemistry.

    Science.gov (United States)

    Valcárcel, M; Christian, G D; Lucena, R

    2013-07-02

    Analytical chemistry is key to the functioning of a modern society. From early days, ethics in measurements have been a concern and that remains today, especially as we have come to rely more on the application of analytical science in many aspects of our lives. The main aim of this Feature is to suggest ways of introducing the topic of social responsibility and its relation to analytical chemistry in undergraduate or graduate chemistry courses.

  2. Student academic achievement in college chemistry

    Science.gov (United States)

    Tabibzadeh, Kiana S.

    General Chemistry is required for variety of baccalaureate degrees, including all medical related fields, engineering, and science majors. Depending on the institution, the prerequisite requirement for college level General Chemistry varies. The success rate for this course is low. The purpose of this study is to examine the factors influencing student academic achievement and retention in General Chemistry at the college level. In this study student achievement is defined by those students who earned grades of "C" or better. The dissertation contains in-depth studies on influence of Intermediate Algebra as a prerequisite compared to Fundamental Chemistry for student academic achievement and student retention in college General Chemistry. In addition the study examined the extent and manner in which student self-efficacy influences student academic achievement in college level General Chemistry. The sample for this part of the study is 144 students enrolled in first semester college level General Chemistry. Student surveys determined student self-efficacy level. The statistical analyses of study demonstrated that Fundamental Chemistry is a better prerequisite for student academic achievement and student retention. The study also found that student self-efficacy has no influence on student academic achievement. The significance of this study will be to provide data for the purpose of establishing a uniform and most suitable prerequisite for college level General Chemistry. Finally the variables identified to influence student academic achievement and enhance student retention will support educators' mission to maximize the students' ability to complete their educational goal at institutions of higher education.

  3. Presidential Green Chemistry Challenge: 2009 Academic Award

    Science.gov (United States)

    Presidential Green Chemistry Challenge 2009 award winner, Professor Krzysztof Matyjaszewski, developed Atom Transfer Radical Polymerization to make polymers with copper catalysts and environmentally friendly reducing agents.

  4. A short textbook of colloid chemistry

    CERN Document Server

    Jirgensons, B

    1962-01-01

    A Short Textbook of Colloid Chemistry, Second Revised Edition details the factual aspect of colloid chemistry that includes the basic facts, established empirical and mathematical relationships, and practical applications. The chapters of the title are organized into two parts. In the first part, the text discusses the general concepts of colloid chemistry, such as the history and scope, basic terms, and basic methods in experiment with colloids. Part Two covers the technical aspect of colloid chemistry, such as the optical properties, electrical properties, and viscosity. The book will be of

  5. Popular Science Articles for Chemistry Teaching

    Directory of Open Access Journals (Sweden)

    Ketevan Kupatadze

    2017-07-01

    Full Text Available The presented paper reviews popular science articles (these articles are published in online magazine “The Teacher” as one of the methods of chemistry teaching. It describes which didactic principles they are in line with and how this type of articles can be used in order to kindle the interest of pupils, students and generally, the readers of other specialties, in chemistry.  The articles review the main topics of inorganic/organic chemistry, biochemistry and ecological chemistry in a simple and entertaining manner. A part of the articles is about "household" chemistry. Chemical topics are related to poetry, literature, history of chemistry or simply, to fun news. The paper delineates the structure of popular science articles and the features of engaging students. It also reviews the teachers' and students' interview results about the usage of popular science articles in chemistry teaching process. The aforementioned pedagogical study revealed that the popular science articles contain useful information not only for the students of other specialties, but also for future biologists and ecologists (having chemistry as a mandatory subject at their universities. The articles are effectively used by teachers on chemistry lessons to kindle students' interest in this subject. DOI: http://dx.doi.org/10.17807/orbital.v9i3.960 

  6. Symposium on high temperature and materials chemistry

    Energy Technology Data Exchange (ETDEWEB)

    1989-10-01

    This volume contains the written proceedings of the Symposium on High Temperature and Materials Chemistry held in Berkeley, California on October 24--25, 1989. The Symposium was sponsored by the Materials and Chemical Sciences Division of Lawrence Berkeley Laboratory and by the College of Chemistry of the University of California at Berkeley to discuss directions, trends, and accomplishments in the field of high temperature and materials chemistry. Its purpose was to provide a snapshot of high temperature and materials chemistry and, in so doing, to define status and directions.

  7. Polysaccharides: The “Click” Chemistry Impact

    Directory of Open Access Journals (Sweden)

    Romain Lucas

    2011-09-01

    Full Text Available Polysaccharides are complex but essential compounds utilized in many areas such as biomaterials, drug delivery, cosmetics, food chemistry or renewable energy. Modifications and functionalizations of such polymers are often necessary to achieve molecular structures of interest. In this area, the emergence of the “click” chemistry concept, and particularly the copper-catalyzed version of the Huisgen 1,3-dipolar cycloaddition reaction between terminal acetylenes and azides, had an impact on the polysaccharides chemistry. The present review summarizes the contribution of “click” chemistry in the world of polysaccharides.

  8. Green analytical chemistry--theory and practice.

    Science.gov (United States)

    Tobiszewski, Marek; Mechlińska, Agata; Namieśnik, Jacek

    2010-08-01

    This tutorial review summarises the current state of green analytical chemistry with special emphasis on environmentally friendly sample preparation techniques. Green analytical chemistry is a part of the sustainable development concept; its history and origins are described. Miniaturisation of analytical devices and shortening the time elapsing between performing analysis and obtaining reliable analytical results are important aspects of green analytical chemistry. Solventless extraction techniques, the application of alternative solvents and assisted extractions are considered to be the main approaches complying with green analytical chemistry principles.

  9. Amphoteric Aqueous Hafnium Cluster Chemistry.

    Science.gov (United States)

    Goberna-Ferrón, Sara; Park, Deok-Hie; Amador, Jenn M; Keszler, Douglas A; Nyman, May

    2016-05-17

    Selective dissolution of hafnium-peroxo-sulfate films in aqueous tetramethylammonium hydroxide enables extreme UV lithographic patterning of sub-10 nm HfO2 structures. Hafnium speciation under these basic conditions (pH>10), however, is unknown, as studies of hafnium aqueous chemistry have been limited to acid. Here, we report synthesis, crystal growth, and structural characterization of the first polynuclear hydroxo hafnium cluster isolated from base, [TMA]6 [Hf6 (μ-O2 )6 (μ-OH)6 (OH)12 ]⋅38 H2 O. The solution behavior of the cluster, including supramolecular assembly via hydrogen bonding is detailed via small-angle X-ray scattering (SAXS) and electrospray ionization mass spectrometry (ESI-MS). The study opens a new chapter in the aqueous chemistry of hafnium, exemplifying the concept of amphoteric clusters and informing a critical process in single-digit-nm lithography. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. The Redox Chemistry of Rainwater

    Science.gov (United States)

    Willey, J. D.; Mullaugh, K. M.; Kieber, R. J.; Avery, B.; Mead, R. N.

    2011-12-01

    Oxidation-reduction processes affect the chemical speciation of many inorganic and organic species in rainwater. The presence and concentrations of certain reactive radicals is also critically dependent upon redox chemistry. There are many oxidants and reductants in rainwater, and hence many competing redox reactions. Measurement of both halves of a redox couple can yield important information about rainwater pe- (-log electron activity) and also identify relevant oxidants and reductants for that particular redox speciation. Several redox couples have been measured in rainwater in Wilmington, NC, USA, as well as at other locations. There are at least three relevant oxidant-reductant couples in rainwater rather than a unique pe-. Mn redox speciation responds to the molecular oxygen-water couple (pe- = 15.9 for rainwater in contact with air and pH of 4.7). Fe, Hg and the nitrate-nitrite-ammonium system appear to be controlled by the molecular oxygen-hydrogen peroxide couple, with hydrogen peroxide acting as a reductant (pe- = 9.2). Cu responds to superoxide as a reductant with molecular oxygen as an oxidant (pe- = 2.7). Direct Pt electrode measurements of redox potential in rainwater consistently yield lower redox potentials than predicted by the molecular oxygen-water couple, indicating the redox chemistry of rainwater is more complex and rainwater is less oxidizing than previously thought.

  11. Cannabinoids: occurrence and medicinal chemistry.

    Science.gov (United States)

    Appendino, G; Chianese, G; Taglialatela-Scafati, O

    2011-01-01

    With an inventory of several hundreds secondary metabolites identified, Cannabis sativa L. (hemp) is one of the phytochemically best characterized plant species. The biomedical relevance of hemp undoubtedly underlies the wealth of data on its constituents and their biological activities, and cannabinoids, a class of unique meroterpenoids derived from the alkylation of an olivetollike alkyl resorcinol with a monoterpene unit, are the most typical constituents of Cannabis. In addition to the well-known psychotropic properties of Δ(9)-THC, cannabinoids have been reported to show potential in various fields of medicine, with the capacity to address unmet needs like the relief of chemotherapy-derived nausea and anorexia, and symptomatic mitigation of multiple sclerosis. Many of the potential therapeutic uses of cannabinoids are related to the interaction with (at least) two cannabinoid G-protein coupled receptors (CB1 and CB2). However, a number of activities, like the antibacterial or the antitumor properties are non totally dependent or fully independent from the interaction with these proteins. These pharmacological activities are particularly interesting since, in principle, they could be easily dissociated by the unwanted psychotropic effects. This review aims at giving readers a survey of the more recent advances in both phytochemistry of C. sativa, the medicinal chemistry of cannabinoids, and their distribution in plants, highlighting the impact that research in these hot fields could have for modern medicinal chemistry and pharmacology.

  12. Recent advances in azaborine chemistry.

    Science.gov (United States)

    Campbell, Patrick G; Marwitz, Adam J V; Liu, Shih-Yuan

    2012-06-18

    The chemistry of organoboron compounds has been primarily dominated by their use as powerful reagents in synthetic organic chemistry. Recently, the incorporation of boron as part of a functional target structure has emerged as a useful way to generate diversity in organic compounds. A commonly applied strategy is the replacement of a CC unit with its isoelectronic BN unit. In particular, the BN/CC isosterism of the ubiquitous arene motif has undergone a renaissance in the past decade. The parent molecule of the 1,2-dihydro-1,2-azaborine family has now been isolated. New mono- and polycyclic B,N heterocycles have been synthesized for potential use in biomedical and materials science applications. This review is a tribute to Dewar's first synthesis of a monocyclic 1,2-dihydro-1,2-azaborine 50 years ago and discusses recent advances in the synthesis and characterization of heterocycles that contain carbon, boron, and nitrogen. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Systemic Changes in the Undergraduate Chemistry Curriculum Program Awards

    Science.gov (United States)

    1995-07-01

    The National Science Foundation has awarded over 10 million in awards to four coalitions in the first round of full awards in the Systemic Changes in the Undergraduate Chemistry Curriculum program. Overall, more than 50 institutions, ranging from large universities to four-year and community colleges, are formally involved in these projects. Each of the projects will involve five years of curricular development and evaluation and dissemination of the results by the participating institutions, as described in the abstracts below. We encourage faculty who are interested in becoming involved in any of these projects to contact the appropriate coalition. In addition, we expect to begin offering an emphasis in 1997 under the Course and Curriculum Development program in which faculty can request funds to assist them in adapting and adopting at their own institutions curricular innovations that have been developed by these coalitions. Another round of proposals for full awards was accepted in June of 1995, and we expect to make one more award in the program during FY1996. We do not expect to accept proposals for either planning or full grants in this program in June of 1996. However, the regular Course and Curriculum Development program will continue to accept and fund proposals requesting support for smaller-scale changes in the chemistry curriculum. ChemLinks Coalition: Making Chemical Connections Brock Spencer Beloit College, Beloit, WI 53511 DUE 9455918: FY1995, 705,000; FY 1996, 655,000; FY1997, 655,000; FY1998, 350,00; FY1999, 350,000 The ChemLinks Coalition is undertaking a five-year project to change the way students learn chemistry, increase scientific literacy for all students taking chemistry, and promote the process of educational reform. In collaboration with the ModularChem Consortium, faculty are developing, testing, and disseminating modular course materials that use active and collaborative approaches to learning. These materials, focused on the first two

  14. Lunar Science Conference, 4th, Houston, Tex., March 5-8, 1973, Proceedings. Volume 1 - Mineralogy and petrology. Volume 2 - Chemical and isotope analyses. Organic chemistry. Volume 3 - Physical properties

    Science.gov (United States)

    Gose, W. A.

    1973-01-01

    The mineralogy, petrology, chemistry, isotopic composition, and physical properties of lunar materials are described in papers detailing methods, results, and implications of research on samples returned from eight lunar landing sites: Apollo 11, 12, 14, 15, 16, 17, and Luna 16 and 20. The results of experiments conducted or set up on the lunar surface by the astronauts are also described along with observations taken from Command Modules and subsatellites. Major topics include general geology, soil and breccia studies, petrologic studies, mineralogic analyses, elemental compositions, radiometric age determinations, rare gas chemistry, radionuclides, organogenic compounds, particle track records, thermal properties, seismic studies, resonance studies, orbital mapping, lunar atmosphere, magnetic studies, electrical studies, optical properties, and microcratering. Individual items are announced in this issue.

  15. Using Chemistry Teaching Aids Based Local Wisdom as an Alternative Media for Chemistry Teaching and Learning

    Science.gov (United States)

    Priyambodo, Erfan; Wulaningrum, Safira

    2017-01-01

    Students have difficulties in relating the chemistry phenomena they learned and the life around them. It is necessary to have teaching aids which can help them to relate between chemistry with the phenomena occurred in everyday life, which is chemistry's teaching aids based on local wisdom. There are 3 teaching aids which used in chemistry…

  16. Understanding the Impact of a General Chemistry Course on Students' Transition to Organic Chemistry

    Science.gov (United States)

    Collins-Webb, Alexandra; Jeffery, Kathleen A.; Sweeder, Ryan D.

    2016-01-01

    The move from general chemistry to organic chemistry can be a challenge for students as it often involves a transition from quantitatively-oriented to mechanistically-oriented thinking. This study found that the design of the general chemistry course can change the student experience of this transition as assessed by a reflective survey. The…

  17. Promoting Chemistry Learning through Undergraduate Work Experience in the Chemistry Lab: A Practical Approach

    Science.gov (United States)

    Yu, Hong-Bin

    2015-01-01

    Hiring undergraduate lab assistants in chemistry departments is common in college. However, few studies have focused on promoting undergraduate chemistry learning and thinking skills through this work experience in chemistry teaching laboratories. This article discusses the strategy we implemented in the lab assistant program. The…

  18. Small-scale chemistry for a hands-on approach to chemistry ...

    African Journals Online (AJOL)

    The purpose of this study was to investigate the possibility of using a small-scale chemistry (SSC) approach as a means of performing chemistry practical activities in Ethiopian secondary schools. A total of eight experiments from two topics, electrolysis and rate of reaction, in the Ethiopian grade 11 chemistry syllabus were ...

  19. Metalloporphyrins as Oxidation Catalysts: Moving toward "Greener" Chemistry in the Inorganic Chemistry Laboratory

    Science.gov (United States)

    Clark, Rose A.; Stock, Anne E.; Zovinka, Edward P.

    2012-01-01

    Training future chemists to be aware of the environmental impact of their work is of fundamental importance to global society. To convince chemists to embrace sustainability, the integration of green chemistry across the entire chemistry curriculum is a necessary step. This experiment expands the reach of green chemistry techniques into the…

  20. Chemistry inside an Epistemological Community Box! Discursive Exclusions and Inclusions in Swedish National Tests in Chemistry

    Science.gov (United States)

    Ståhl, Marie; Hussénius, Anita

    2017-01-01

    This study examined the Swedish national tests in chemistry for implicit and explicit values. The chemistry subject is understudied compared to biology and physics and students view chemistry as their least interesting science subject. The Swedish national science assessments aim to support equitable and fair evaluation of students, to concretize…