Correction: Synthesis of pyrrolidine-3-carboxylic acid derivatives via asymmetric Michael addition reactions of carboxylate-substituted enones.

Science.gov (United States)

Yin, Feng; Garifullina, Ainash; Tanaka, Fujie

2018-04-25

Correction for 'Synthesis of pyrrolidine-3-carboxylic acid derivatives via asymmetric Michael addition reactions of carboxylate-substituted enones' by Feng Yin et al., Org. Biomol. Chem., 2017, 15, 6089-6092.

Asymmetric synthesis of α-amino acids via homologation of Ni(II) complexes of glycine Schiff bases. Part 3: Michael addition reactions and miscellaneous transformations.

Science.gov (United States)

Aceña, José Luis; Sorochinsky, Alexander E; Soloshonok, Vadim

2014-09-01

The major goal of this review is a critical discussion of the literature data on asymmetric synthesis of α-amino acids via Michael addition reactions involving Ni(II)-complexes of amino acids. The material covered is divided into two conceptually different groups dealing with applications of: (a) Ni(II)-complexes of glycine as C-nucleophiles and (b) Ni(II)-complexes of dehydroalanine as Michael acceptors. The first group is significantly larger and consequently subdivided into four chapters based on the source of stereocontrolling element. Thus, a chiral auxiliary can be used as a part of nucleophilic glycine Ni(II) complex, Michael acceptor or both, leading to the conditions of matching vs. mismatching stereochemical preferences. The particular focus of the review is made on the practical aspects of the methodology under discussion and mechanistic considerations.

The Relation between Hepatotoxicity and the Total Coumarin Intake from Traditional Japanese Medicines Containing Cinnamon Bark.

Science.gov (United States)

Iwata, Naohiro; Kainuma, Mosaburo; Kobayashi, Daisuke; Kubota, Toshio; Sugawara, Naoko; Uchida, Aiko; Ozono, Sahoko; Yamamuro, Yuki; Furusyo, Norihiro; Ueda, Koso; Tahara, Eiichi; Shimazoe, Takao

2016-01-01

Cinnamon bark is commonly used in traditional Japanese herbal medicines (Kampo medicines). The coumarin contained in cinnamon is known to be hepatotoxic, and a tolerable daily intake (TDI) of 0.1 mg/kg/day, has been quantified and used in Europe to insure safety. Risk assessments for hepatotoxicity by the cinnamon contained in foods have been reported. However, no such assessment of cinnamon bark has been reported and the coumarin content of Kampo medicines derived from cinnamon bark is not yet known. To assess the risk for hepatotoxicity by Kampo medicines, we evaluated the daily coumarin intake of patients who were prescribed Kampo medicines and investigated the relation between hepatotoxicity and the coumarin intake. The clinical data of 129 outpatients (18 male and 111 female, median age 58 years) who had been prescribed keishibukuryogankayokuinin (TJ-125) between April 2008 and March 2013 was retrospectively investigated. Concurrent Kampo medicines and liver function were also surveyed. In addition to TJ-125, the patients took some of the other 32 Kampo preparations and 22 decoctions that include cinnamon bark. The coumarin content of these Kampo medicines was determined by high performance liquid chromatography (HPLC). TJ-125 had the highest daily content of coumarin (5.63 mg/day), calculated from the daily cinnamon bark dosage reported in the information leaflet inserted in each package of Kampo medicine. The coumarin content in 1g cinnamon bark decoction was 3.0 mg. The daily coumarin intake of the patients was 0.113 (0.049-0.541) mg/kg/day, with 98 patients (76.0%) exceeding the TDI. Twenty-three patients had an abnormal change in liver function test value, but no significant difference was found in the incidence of abnormal change between the group consuming less than the TDI value (6/31, 19.4%) and the group consuming equal to or greater than the TDI value (17/98, 17.3%). In addition, no abnormal change related to cinnamon bark was found for individual

Aza‐Michael addition reaction: Post‐polymerization modification and preparation of PEI/PEG‐based polyester hydrogels from enzymatically synthesized reactive polymers

DEFF Research Database (Denmark)

Hoffmann, Christian; Stuparu, Mihaiela C.; Daugaard, Anders Egede

2015-01-01

The utility of aza‐Michael addition chemistry for post‐polymerization functionalization of enzymatically prepared polyesters is established. For this, itaconate ester and oligoethylene glycol are selected as monomers. A Candida Antarctica lipase B catalyzed polycondensation reaction between the two...... monomers provides the polyesters, which carry an activated carbon‐carbon double bond in the polymer backbone. These electron deficient alkenes represent suitable aza‐Michael acceptors and can be engaged in a nucleophilic addition reaction with small molecular mono‐amines (aza‐Michael donors) to yield...... functionalized linear polyesters. Employing a poly‐amine as the aza‐Michael donor, on the other hand, results in the formation of hydrophilic polymer networks....

Synthesis of some pyridine and pyrimidine derivatives via Michael-Addition

International Nuclear Information System (INIS)

El-Baih, Fatma E.M.; Al-Rasheed, Hessa H.; Al-Hazimi, Hassan M.

2006-01-01

Synthesis of pyridine and pyrimidine analogues 4 and 6-9 were achieved by Michael-addition of compounds containing either active methylene groups like, malononitrile , ethyl cyanoacetate and 1-tetralone or compounds containing active hydrogen atoms like, guanidine in the presence of an oxidizing agent and thiourea to 2-arylmethylidine-1-tetralone and 2-arylmethylidine-6-methoxy-1-tetralone (2) (enones). Addition of malononitrile in piperidine at room temperature to 2-amino-3-cyno-naphtho [1, 2-malonoitrile in sodium alkoxide or sodium hydroxide to 2 gave 4. Cyclization of 3a with acetic anhydride in the presence of conc. H2sO4 gave the naphtha-pyrano[2, 3-d]pyrimidin-8-one (5). Condensation of the pyrimidine thione derivatives 9 with chloroacetic acid gave the 3-oxobenzo[h]thiazoladino[2, 3-b]quinazoline derivatives (10), which were reacted through their active methylene groups with aromatic aldehydes to give the arylidine derivatives 11. These compounds were also prepared in one step by reacting 9 with chloroacetic acid and aromatic aldehydes. Condensation of 9 with 3-bromopropanoic acid gave 4-oxo-benzo[h]1, 3-thiazino[2, 3-b]quinazoline derivatives (12). The structures of the prepared compounds were mainly confirmed on the basis of spectroscopic methods. (author)

Tandem Aldol-Michael Reactions in Aqueous Diethylamine Medium: A Greener and Efficient Approach to Bis-Pyrimidine Derivatives

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Abdullah M. Al-Majid

2013-12-01

Full Text Available A simple protocol, involving the green synthesis for the construction of novel bis-pyrimidine derivatives, 3a–i and 4a–e are accomplished by the aqueous diethylamine media promoted tandem Aldol-Michael reaction between two molecules of barbituric acid derivatives 1a,b with various aldehydes. This efficient synthetic protocol using an economic and environmentally friendly reaction media with versatility and shorter reaction time provides bis-pyrimidine derivatives with high yields (88%–99%.

Highly efficient exciplex organic light-emitting diodes incorporating a heptazine derivative as an electron acceptor.

Science.gov (United States)

Li, Jie; Nomura, Hiroko; Miyazaki, Hiroshi; Adachi, Chihaya

2014-06-11

Highly efficient exciplex systems incorporating a heptazine derivative () as an electron acceptor and 1,3-di(9H-carbazol-9-yl)benzene () as an electron donor are developed. An organic light-emitting diode containing 8 wt% : as an emitting layer exhibits a maximum external quantum efficiency of 11.3%.

Prime and boost aerosol exposure via fog machine or shisha smoke followed by cinnamon hypersensitivity and anaphylaxis to spiced food.

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Jensen-Jarolim, Erika; Roth-Walter, Franziska; Leitner, Erich; Buchleitner, Stefan; Vogelsang, Harald; Kinaciyan, Tamar

2016-01-01

Cinnamon aldehyde (alias cinnamaldehyde) is widely used in food, textile or cosmetic industry. It is mostly associated with contact allergy, but immediate type allergies have been reported. The present study was triggered by a case of anaphylactic events to cinnamon in food and upon skin prick test. We investigated a possible correlation of exposure to a disco fog machine and/or shisha consumption with immediate type hypersensitivity to cinnamon aldehyde in the patient and healthy volunteers. In both fog machines and shisha pipes heating of glycerol-based fluids before evaporation renders chemical transversion to malodorous acrolein. Therefore, both methods are frequently operated with aroma additives. Cinnamon aldehyde and derivatives could be detected by gas chromatography in sampled fog flavored with cola fragrance. The patient as well as healthy (mostly female) volunteers were skin prick tested using cinnamon aldehyde diluted in 0.9 % NaCl, Vaseline® or fog fluid. Persons with a history of exposure to disco fog or shisha (n = 10, mean 32.8 years) reacted with a significantly larger wheal and flare reaction in the skin test (p = 0.0115, p = 0.0146, or p = 0.098) than the non-exposed (n = 8, mean 37.3 years). Both groups were gender matched, but differed in the mean age by 4.5 years. This reaction was specific as compared to skin reactivity to cinnamon alcohol, with only a trend to higher reactivity in exposed persons (ns). From our data we conclude that hapten fragrances such as cinnamon aldehyde may during heating in glycerol fluids associate to complete antigens and via inspiration lead to specific immediate type hypersensitivity. In some cases the hypersensitivity may be unmasked by spiced food containing cinnamon aldehyde or related chemicals, and lead to severe adverse reactions.

Cinnamon: Mystic powers of a minute ingredient

OpenAIRE

Pallavi Kawatra; Rathai Rajagopalan

2015-01-01

Cinnamon, due to its exotic flavor and aroma, is a key ingredient in the kitchen of every household. From the beginning of its use in 2800 BC by our ancestors for various purposes such as anointment, embalming and various ailments, it has instigated the interest of many researchers. Recently many trials have explored the beneficial effects of cinnamon in Parkinsons, diabetes, blood, and brain. After extensive research on PubMed and Google scholar, data were collected regarding its antioxidant...

In vivo and in vitro antidiabetic effects of aqueous cinnamon extract and cinnamon polyphenol-enhanced food matrix

Science.gov (United States)

Cheng, Diana M.; Kuhn, Peter; Poulev, Alexander; Rojo, Leonel E.; Lila, Mary Ann; Raskin, Ilya

2012-01-01

Cinnamon has a long history of medicinal use and continues to be valued for its therapeutic potential for improving metabolic disorders such as type 2 diabetes. In this study, a phytochemically-enhanced functional food ingredient that captures water soluble polyphenols from aqueous cinnamon extract (CE) onto a protein rich matrix was developed. CE and cinnamon polyphenol-enriched defatted soy flour (CDSF) were effective in acutely lowering fasting blood glucose levels in diet-induced obese hyperglycemic mice at 300 and 600 mg/kg, respectively. To determine mechanisms of action, rat hepatoma cells were treated with CE and eluates of CDSF at a range of 1–25 µg/ml. CE and eluates of CDSF demonstrated dose-dependent inhibition of hepatic glucose production with significant levels of inhibition at 25 µg/ml. Furthermore, CE decreased the gene expression of two major regulators of hepatic gluconeogenesis, phosphoenolpyruvate carboxykinase and glucose-6-phosphatase. The hypoglycemic and insulin-like effects of CE and CDSF may help to ameliorate type 2 diabetes conditions. PMID:22980902

Controversies surrounding the clinical potential of cinnamon for the management of diabetes.

Science.gov (United States)

Rafehi, H; Ververis, K; Karagiannis, T C

2012-06-01

Obesity levels have increased significantly in the past five decades and are predicted to continue rising, resulting in important health implications. In particular, this has translated to an increase in the occurrence of type II diabetes mellitus (T2D). To alleviate associated problems, certain nutraceuticals have been considered as potential adjuncts or alternatives to conventional prescription drugs. Cinnamon, a commonly consumed spice originating from South East Asia, is currently being investigated as a potential preventative supplement and treatment for insulin resistance, metabolic syndrome and T2D. Extensive in vitro evidence has shown that cinnamon may improve insulin resistance by preventing and reversing impairments in insulin signalling in skeletal muscle. In adipose tissue, it has been shown that cinnamon increases the expression of peroxisome proliferator-activated receptors including, PPARγ. This is comparable to the action of commonly used thiazolinediones, which are PPAR agonists. Studies have also shown that cinnamon has potent anti-inflammatory properties. However, numerous human clinical trials with cinnamon have been conducted with varying findings. While some studies have showed no beneficial effect, others have indicated improvements in cholesterol levels, systolic blood pressure, insulin sensitivity and postprandial glucose levels with cinnamon. However, the only measurement consistently improved by cinnamon consumption is fasting glucose levels. While it is still premature to suggest the use of cinnamon supplementation based on the evidence, further investigation into mechanisms of action is warranted. Apart from further characterization of genetic and epigenetic changes in model systems, systematic large-scale clinical trials are required. In this study, we discuss the mechanisms of action of cinnamon in the context of T2D and we highlight some of the associated controversies. © 2011 Blackwell Publishing Ltd.

The anti-oxidant effects of ginger and cinnamon on ...

African Journals Online (AJOL)

Ginger and cinnamon are strong anti-oxidants and have been shown to reduce oxidative stress in the long-term treatment of streptozotocin (STZ)-induced diabetes in animal models. The present study examined the influence of combined ginger and cinnamon on spermatogenesis in STZ-induced diabetes in maleWistar rats ...

Polythiophenes and fullerene derivatives based donor-acceptor system: topography by atomic force microscopy

International Nuclear Information System (INIS)

Marcakova, M. L.; Repovsky, D.; Cik, G.; Velic, D.

2017-01-01

The goal of this work is to examine the surface of a polythiophene/fullerene film in order to understand the structure. In this work polythiophene is used as electron donor and fullerene-derivative is used as electron acceptor. Atomic force microscopy (AFM), is an ideal method to study surfaces and nanostructures. Surfaces of fullerene C60 , fullerene-derivates PCBM, polythiophene P12 and a mixture of P12 and PCBM are characterized. In all samples, the average roughness, the arithmetical value of divergence from the high of the surface, is determined concluding that P12 and PCBM mix together well and form a film with specific topography. (authors)

Assessment of Coumarin Levels in Ground Cinnamon Available in the Czech Retail Market

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Jana Blahová

2012-01-01

Full Text Available The objective of this study was to determine the coumarin content of ground cinnamon purchased from retail markets in the Czech Republic. No sample was labelled with information on the botanical source, but, in some cases, the countries of origin were specified. For comparison, a single cinnamon sample imported directly from a plantation in Sri Lanka that came from Cinnamomum verum was analyzed. Results from 60 ground cinnamon samples comprising twelve brands confirmed a high content of coumarin, with mean levels ranging from 2 650 to 7 017 mg · kg−1. The high coumarin content confirmed that these cinnamon samples obtained from cassia cinnamon were in contrast to the sample from Sri Lanka, which was coumarin-free.

Photostimulated luminescence detection and radiation effects on cinnamon (Cinnamomum zeylanicum) spice

International Nuclear Information System (INIS)

Marcazzó, J.; Sanchez-Barrera, C.E.; Urbina-Zavala, A.; Cruz-Zaragoza, E.

2015-01-01

The increase of disease borne pathogens in foods has promoted the use of new technologies in order to eliminate these pathogen microorganisms and extend the shelf-life of the foodstuffs. In particular, Cinnamon (Cinnamomum zeylanicum) contains an important number of pathogen microorganisms and it is frequently sterilized by gamma radiation. However, it is important to develop the detection methods for irradiated food in order to keep the dose control and also to analyze the radiation effects in their chemical property. This work reports (i) the photostimulated luminescence (PSL) detection of irradiated cinnamon and thermoluminescence (TL) detection of the inorganic polymineral fraction separated from this spice, and (ii) the proximate chemical analysis carried out on fat, protein and dietetic fiber contents. The detection limits using the PSL and TL methods were 500 Gy and 10 Gy, respectively, and the fat content was increased significantly with the gamma dose that could be related to the lipid oxidation in the cinnamon. - Highlights: • Samples of cinnamon (Cinnamomum zeylanicum) were studied by TL and PSL methods. • The cinnamon was detected as irradiated at a dose of 500 Gy using PSL. • TL method shows an excellent linear response for doses lesser than 500 Gy. • A proximate chemical analysis was carried out on fat, protein and dietetic fiber. • The TL and PSL responses can be used for dose control in commercial cinnamon

Effect of radiation processing on the antioxidant activity of Sage and Cinnamon

International Nuclear Information System (INIS)

El-Niley, H. F. G.; Farag, M. D. H.

2012-12-01

In the present study, the effect of radiation processing on dried sage leaves and cinnamon barks samples were carried out at dose level of 25 kGy. Total phenolic content was determined in the extracts of these herbs alongside the antioxidant properties of their methanoic extracts were assessed using reducing power assay and by DPPH radical test within an extract concentration range 2.5 to 40 mg/ml of methanol. The result showed the total phenolic compounds were increased by 11.18% and 10.19% for irradiated sage and cinnamon, respectively. The values of EC 50 estimated from the results of reducing power assay and DPPH radical test showed the sage extracts had higher antioxidant activity tham cinnamon extracts. In summary, gamma- irradiation of dried sage leaves and cinnamon barks was found to be significantly increase the antioxidant properties of dried sage leaves and cinnamon barks but also enhanced the antioxidant properties, to some extent. (Author)

Effects of short-term cinnamon ingestion on in vivo glucose tolerance

DEFF Research Database (Denmark)

Solomon, Thomas; Blannin, A K

2007-01-01

Various spices display insulin-potentiating activity in vitro, and in particular, cinnamon spice and its phenolic extracts have been shown to exhibit these capabilities. In vivo study shows that cinnamon may have beneficial effects on glucose homeostasis; therefore the aim of this study...

Effects of Cinnamon Extract on Cerebellum Histomorphometry in Diabetic Rats’ Fetus

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AR Rafati

2013-10-01

Full Text Available Abstract Background & aim: In pregnant women, maternal diabetes occurs when the pancreas does not produce enough insulin, so glucose increases in the mother's blood and the blood of the fetus therefore causing many complications in children. The aim of this study was to evaluate the effects of cinnamon on morphometric histologic changes on fetal cerebellum of diabetic rats at days 18 and 20. Methods: In this study, 32 healthy female Wistar rats were prepared and randomly divided into four groups, normal control, diabetic, healthy subjects treated with cinnamon and cinnamon extract-treated diabetic groups. Diabetic groups were subjected by intraperitoneal of streptozotocin. All groups were charged with natural mating and they received a dose of 60 mg/ kg of cinnamon at the first day off pregnancy. After formation of the nervous system, in the eighteenth and twentieth day of pregnancy, the mother of the four mice were anesthetized and the fetus was removed for sampling. The histological slides were prepared and various parameters were studied in the cerebellum. Data were analyzed using one-way ANOVA and Duncan test. Results: The thickness of gray matter, and the gray matter white cells in the cerebellum of diabetic rats compared to other groups tested at days of18 and 20 and embryonic cells in the white matter of the cerebellum at day 18 was significantly decreased (p< 0.05. Conclusion: Administration of cinnamon extract reduces mothers’ blood sugar levels therefore preventing the complications of diabetes on the fetal cerebellum. Key words: cinnamon extract, Diabetes, cerebellum, Rat.

Cinnamon extract induces tumor cell death through inhibition of NFκB and AP1

International Nuclear Information System (INIS)

Kwon, Ho-Keun; Lee, Sung Haeng; Park, Zee Yong; Im, Sin-Hyeog; Hwang, Ji-Sun; So, Jae-Seon; Lee, Choong-Gu; Sahoo, Anupama; Ryu, Jae-Ha; Jeon, Won Kyung; Ko, Byoung Seob; Im, Chang-Rok

2010-01-01

Cinnamomum cassia bark is the outer skin of an evergreen tall tree belonging to the family Lauraceae containing several active components such as essential oils (cinnamic aldehyde and cinnamyl aldehyde), tannin, mucus and carbohydrate. They have various biological functions including anti-oxidant, anti-microbial, anti-inflammation, anti-diabetic and anti-tumor activity. Previously, we have reported that anti-cancer effect of cinnamon extracts is associated with modulation of angiogenesis and effector function of CD8 + T cells. In this study, we further identified that anti-tumor effect of cinnamon extracts is also link with enhanced pro-apoptotic activity by inhibiting the activities NFκB and AP1 in mouse melanoma model. Water soluble cinnamon extract was obtained and quality of cinnamon extract was evaluated by HPLC (High Performance Liquid Chromatography) analysis. In this study, we tested anti-tumor activity and elucidated action mechanism of cinnamon extract using various types of tumor cell lines including lymphoma, melanoma, cervix cancer and colorectal cancer in vitro and in vivo mouse melanoma model. Cinnamon extract strongly inhibited tumor cell proliferation in vitro and induced active cell death of tumor cells by up-regulating pro-apoptotic molecules while inhibiting NFκB and AP1 activity and their target genes such as Bcl-2, BcL-xL and survivin. Oral administration of cinnamon extract in melanoma transplantation model significantly inhibited tumor growth with the same mechanism of action observed in vitro. Our study suggests that anti-tumor effect of cinnamon extracts is directly linked with enhanced pro-apoptotic activity and inhibition of NFκB and AP1 activities and their target genes in vitro and in vivo mouse melanoma model. Hence, further elucidation of active components of cinnamon extract could lead to development of potent anti-tumor agent or complementary and alternative medicine for the treatment of diverse cancers

Quality and storage characteristics of yogurt containing Lacobacillus sakei ALI033 and cinnamon ethanol extract

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Yu Jin Choi

2016-04-01

Full Text Available Abstract Background This study was conducted to examine the quality and storage characteristics of yogurt containing antifungal-active lactic acid bacteria (ALH, Lacobacillus sakei ALI033 isolated from kimchi and cinnamon ethanol extract. The starter was used for culture inoculation (1.0 % commercial starter culture YF-L812 and ALH. Results The antifungal activity of cinnamon extracts was observed in treatments with either cinnamon ethanol extracts or cinnamon methanol extracts. Changes in fermented milk made with ALH and cinnamon extract during fermentation at 40 °C were as follows. The pH was 4.6 after only 6 h of fermentation. Titratable acidity values were maintained at 0.8 % in all treatment groups. Viable cell counts were maintained at 4 × 109 CFU/mL in all groups except for 1.00 % cinnamon treatment. Sensory evaluations of fermented milk sample made with ALH and 0.05 % cinnamon ethanol extract were the highest. Changes in fermented milk made with ALH and cinnamon ethanol extract during storage at 4 °C for 28 days were as follows. In fermented milk containing ALH and cinnamon ethanol extracts, the changes in pH and titratable acidity were moderate and smaller compared with those of the control. Viable cell counts were maintained within a proper range of 108 CFU/mL. Conclusions The results of this study suggest that the overgrowth of fermentation strains or post acidification during storage can be effectively delayed, thereby maintaining the storage quality of yogurt products in a stable way, using cinnamon ethanol extract, which exhibits excellent antifungal and antibacterial activity, in combination with lactic acid bacteria isolated from kimchi.

Effect of cinnamon extract on blood glucose level and lipid profile in alloxan induced diabetic rats

International Nuclear Information System (INIS)

Mahmood, S.; Khurshid, R.

2011-01-01

Background: Cinnamon has been shown to potentiate the hypoglycaemic effect of insulin through up regulation of the glucose uptake in cultured adipocytes of rats. This study tried to find out the effect of Cinnamon alone or in combination with Insulin in diabetic albino rats. Methods: Thirty rats were divided into three groups, A and B. Group A were given cinnamon extract 200 mg/Kg body weight daily orally and group B rats were given cinnamon extract 400 mg/Kg body weight daily. After six weeks blood glucose and lipid profile levels were evaluated in all the groups. Results: Group of rats given 200 mg cinnamon extract showed significant decrease of blood glucose concentration but there was slight or no change in the level of lipid parameters including serum cholesterol, triglyceride and lipoproteins (HDL, LDL-chol). On the other hand group of rats given 400 mg extract of cinnamon showed a better but non significant change in level of lipid related parameter while blood glucose level was significantly decreased. Conclusion: The cinnamon at a dose of 400 mg showed same effects on blood glucose level but better effects on lipid profiles especially of serum cholesterol level of group of rats compared to 200 mg of cinnamon extract. Cinnamon may be recommended as hypoglycaemic herb but not as hypolipidaemic herb. (author)

Asymmetric Michael Addition Mediated by Chiral Ionic Liquids.

Science.gov (United States)

Suzuki, Yumiko

2018-06-01

Chiral ionic liquids with a focus on their applications in asymmetric Michael additions and related reactions were reviewed. The examples were classified on the basis of the mode of asymmetric induction (e.g., external induction/non-covalent interaction or internal induction/covalent bond formation), the roles in reactions (as a solvent or catalyst), and their structural features (e.g., imidazolium-based chiral cations, other chiral oniums; proline derivatives). Most of the reactions with high chiral induction are Michael addition of ketones or aldehydes to chalcones or nitrostyrenes where proline-derived chiral ionic liquids catalyze the reaction through enamine/ iminium formation. Many reports demonstrate the recyclability of ionic liquid-tagged pyrrolidines.

The anti-oxidant effects of ginger and cinnamon on spermatogenesis dys-function of diabetes rats.

Science.gov (United States)

Khaki, Arash; Khaki, Amir Afshin; Hajhosseini, Laleh; Golzar, Farhad Sadeghpour; Ainehchi, Nava

2014-01-01

Diabetes rats have been linked to reproductive dysfunction and plant medicine has been shown to be effective in its treatment. Antioxidants have distinctive effects on spermatogenesis, sperm biology and oxidative stress, and changes in anti-oxidant capacity are considered to be involved in the pathogenesis of chronic diabetes mellitus. Ginger and cinnamon are strong anti-oxidants and have been shown to reduce oxidative stress in the long-term treatment of streptozotocin (STZ)-induced diabetes in animal models. The present study examined the influence of combined ginger and cinnamon on spermatogenesis in STZ-induced diabetes in male Wistar rats. Animals (n = 80) were allocated randomly into eight groups, 10 each: Group 1: Control rats given only 5cc Normal saline (0.9% NaCl) daily;Group2: rats received ginger (100mg/kg/rat) daily; Group 3: rats received cinnamon (75mg/kg) daily; Group 4: rats received ginger and cinnamon, (100mg/kg/rat ginger and 75mg/kg cinnamon) daily; Group 5: Diabetic control rats received only normal saline. Group 6: Diabetic rats received 100mg/kg/day ginger; Group 7: Diabetic rats received 75mg /kg/ day cinnamon; Group 8: Diabetic rats received ginger and cinnamon (100mg/kg/day and 75mg/kg /day). Diabetes was induced with 55 mg/kg, single intra-peritoneal injection of STZ in all groups. At the end of the experiment (56th day), blood samples were taken for determination of testosterone, LH,FSH, total anti-oxidant capacity, and levels of malondialdehyde, SOD, Catalase and GPX. All rats were euthanized, testes were dissected out and spermatozoa were collected from the epididymis for analysis. Sperm numbers, percentages of sperm viability and motility, and total serum testosterone increased in ginger and cinnamon and combined ginger and cinnamon treated diabetic rats compared with control groups. Serum testosterone, LH and FSH were higher compared to control group and also serum anti-oxidants (TAC, SOD, GPX and catalase) all were increased at the

Asymmetric Michael Addition Mediated by Chiral Ionic Liquids

Science.gov (United States)

Suzuki, Yumiko

2018-01-01

Chiral ionic liquids with a focus on their applications in asymmetric Michael additions and related reactions were reviewed. The examples were classified on the basis of the mode of asymmetric induction (e.g., external induction/non-covalent interaction or internal induction/covalent bond formation), the roles in reactions (as a solvent or catalyst), and their structural features (e.g., imidazolium-based chiral cations, other chiral oniums; proline derivatives). Most of the reactions with high chiral induction are Michael addition of ketones or aldehydes to chalcones or nitrostyrenes where proline-derived chiral ionic liquids catalyze the reaction through enamine/ iminium formation. Many reports demonstrate the recyclability of ionic liquid-tagged pyrrolidines. PMID:29861702

Effects of irradiation on natural antioxidants of cinnamon (Cinnamomum zeylanicum N.)

Energy Technology Data Exchange (ETDEWEB)

Kitazuru, E.R. E-mail: erkitazu@ipen.br; Moreira, A.V.B.; Mancini-Filho, J. E-mail: jmamcini@usp.br; Delincee, H.; Villavicencio, A.L.C.H. E-mail: villavic@ipen.br

2004-10-01

Food irradiation to reduce the number of spoilage microorganisms and insects is an ionizing process that induces free radical formation in proteins, lipids, carbohydrates and other molecular structures in food. Antioxidants generally decrease the level of oxidation in such systems by transferring hydrogen atoms to the free radical structure. In the present paper, the effect of ionizing radiation on natural cinnamon antioxidants is studied. Cinnamon samples were purchased from retailers and irradiated with a {sup 60}Co source, Gammacell 220 (A.E.C.L.) installed at IPEN (Sao Paulo, Brazil) using 0, 5, 10, 15, 20, 25 kGy at room temperature. After irradiation 3 kinds of sequential extractions were performed. One was submitted to antioxidant extraction using ethyl ether, the second with ethanol and the last with water. The antioxidant activity was determined by {beta}-carotene/linoleic acid co-oxidation. Irradiation in the dose range applied did not have any effect on the antioxidant potential of the cinnamon compounds. Further studies will be performed to study the possibility to use cinnamon extracts in preserving food from oxidative damage induced by ionizing radiation.

Effects of irradiation on natural antioxidants of cinnamon (Cinnamomum zeylanicum N.)

International Nuclear Information System (INIS)

Kitazuru, E.R.; Moreira, A.V.B.; Mancini-Filho, J.; Delincee, H.; Villavicencio, A.L.C.H.

2004-01-01

Food irradiation to reduce the number of spoilage microorganisms and insects is an ionizing process that induces free radical formation in proteins, lipids, carbohydrates and other molecular structures in food. Antioxidants generally decrease the level of oxidation in such systems by transferring hydrogen atoms to the free radical structure. In the present paper, the effect of ionizing radiation on natural cinnamon antioxidants is studied. Cinnamon samples were purchased from retailers and irradiated with a 60 Co source, Gammacell 220 (A.E.C.L.) installed at IPEN (Sao Paulo, Brazil) using 0, 5, 10, 15, 20, 25 kGy at room temperature. After irradiation 3 kinds of sequential extractions were performed. One was submitted to antioxidant extraction using ethyl ether, the second with ethanol and the last with water. The antioxidant activity was determined by β-carotene/linoleic acid co-oxidation. Irradiation in the dose range applied did not have any effect on the antioxidant potential of the cinnamon compounds. Further studies will be performed to study the possibility to use cinnamon extracts in preserving food from oxidative damage induced by ionizing radiation

Utilization of Cinnamon Leaf and Shrimp Flour as an Enhancer of Catfish Meat Quality

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Mia Setiawati

2017-04-01

Full Text Available Catfish (Pangasianodon hypophthalmus is a freshwater fish that has been produced in the form of a filet. One of the problems in producing good catfish fillet is compactness and brightness of catfish farmed meat. This research aimed to get feed formulation as enhancer meat quality of striped catfish with added Cinnamon leaves flour (Cinnamomum burmannii and used shrimp head meal. A Fish with a weight of 208.98±25.76 g reared in 12 floating nets cage (2x1x1.5 m3 with density of 15 fish/nets for 60 days. As treatment, fish were fed with feed contains 1% cinnamon leaves, 45% shrimp head meal, and combined of cinnamon leaves and shrimp head meal, and as control used feed were formulated without cinnamon leaves and shrimp head meal. Fish were fed 2 times a daily with feeding rate 3.5% of average body weight of fish. The test parameters observed were physical, chemical and organoleptic test of catfish meat. The results showed feed with contains cinnamon leaves and shrimp head meal could decrease level of body fat 14.7% compared than control (p<0.05. Feed with used cinnamon leaves and shrimp head meal gave a texture of fillet fish more compact, elastic and color of fillet fish white. Keywords: Cinnamomum burmannii, fillet, shrimp head meal, feed formulated, Pangasianodon hypophthalmus

Utilization of Cinnamon Leaf and Shrimp Flour as an Enhancer of Catfish Meat Quality

Directory of Open Access Journals (Sweden)

Mia Setiawati

2017-05-01

Full Text Available Catfish (Pangasianodon hypophthalmus is a freshwater fish that has been produced in the form of a filet. One of the problems in producing good catfish fillet is compactness and brightness of catfish farmed meat. This research aimed to get feed formulation as enhancer  meat quality of striped catfish with added Cinnamon leaves flour (Cinnamomum burmannii  and used shrimp head meal. A Fish with a weight of  208.98±25.76 g reared in 12 floating nets cage (2x1x1.5 m3 with density of 15 fish/nets for 60 days. As treatment, fish were fed with feed contains 1% cinnamon leaves,  45% shrimp head meal, and combined of cinnamon leaves and shrimp head meal, and as control used feed were formulated without cinnamon leaves and shrimp head meal. Fish were fed 2 times a daily with feeding rate 3.5% of average body weight offish. The test parameters observed were physical, chemical and organoleptic test of catfish meat. The results showed feed with contains cinnamon leaves and shrimp head meal could decrease level of body fat 14.7% compared than control (p<0.05. Feed with used cinnamon leaves and shrimp head meal gave a texture offillet fish more compact,  elastic and color of fillet fish white.

Cinnamon extract inhibits α-glucosidase activity and dampens postprandial glucose excursion in diabetic rats

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Thirumurugan Kavitha

2011-06-01

Full Text Available Abstract Background α-glucosidase inhibitors regulate postprandial hyperglycemia (PPHG by impeding the rate of carbohydrate digestion in the small intestine and thereby hampering the diet associated acute glucose excursion. PPHG is a major risk factor for diabetic vascular complications leading to disabilities and mortality in diabetics. Cinnamomum zeylanicum, a spice, has been used in traditional medicine for treating diabetes. In this study we have evaluated the α-glucosidase inhibitory potential of cinnamon extract to control postprandial blood glucose level in maltose, sucrose loaded STZ induced diabetic rats. Methods The methanol extract of cinnamon bark was prepared by Soxhlet extraction. Phytochemical analysis was performed to find the major class of compounds present in the extract. The inhibitory effect of cinnamon extract on yeast α-glucosidase and rat-intestinal α-glucosidase was determined in vitro and the kinetics of enzyme inhibition was studied. Dialysis experiment was performed to find the nature of the inhibition. Normal male Albino wistar rats and STZ induced diabetic rats were treated with cinnamon extract to find the effect of cinnamon on postprandial hyperglycemia after carbohydrate loading. Results Phytochemical analysis of the methanol extract displayed the presence of tannins, flavonoids, glycosides, terpenoids, coumarins and anthraquinones. In vitro studies had indicated dose-dependent inhibitory activity of cinnamon extract against yeast α-glucosidase with the IC 50 value of 5.83 μg/ml and mammalian α-glucosidase with IC 50 value of 670 μg/ml. Enzyme kinetics data fit to LB plot pointed out competitive mode of inhibition and the membrane dialysis experiment revealed reversible nature of inhibition. In vivo animal experiments are indicative of ameliorated postprandial hyperglycemia as the oral intake of the cinnamon extract (300 mg/kg body wt. significantly dampened the postprandial hyperglycemia by 78.2% and 52

Cinnamon extract inhibits α-glucosidase activity and dampens postprandial glucose excursion in diabetic rats

Science.gov (United States)

2011-01-01

Background α-glucosidase inhibitors regulate postprandial hyperglycemia (PPHG) by impeding the rate of carbohydrate digestion in the small intestine and thereby hampering the diet associated acute glucose excursion. PPHG is a major risk factor for diabetic vascular complications leading to disabilities and mortality in diabetics. Cinnamomum zeylanicum, a spice, has been used in traditional medicine for treating diabetes. In this study we have evaluated the α-glucosidase inhibitory potential of cinnamon extract to control postprandial blood glucose level in maltose, sucrose loaded STZ induced diabetic rats. Methods The methanol extract of cinnamon bark was prepared by Soxhlet extraction. Phytochemical analysis was performed to find the major class of compounds present in the extract. The inhibitory effect of cinnamon extract on yeast α-glucosidase and rat-intestinal α-glucosidase was determined in vitro and the kinetics of enzyme inhibition was studied. Dialysis experiment was performed to find the nature of the inhibition. Normal male Albino wistar rats and STZ induced diabetic rats were treated with cinnamon extract to find the effect of cinnamon on postprandial hyperglycemia after carbohydrate loading. Results Phytochemical analysis of the methanol extract displayed the presence of tannins, flavonoids, glycosides, terpenoids, coumarins and anthraquinones. In vitro studies had indicated dose-dependent inhibitory activity of cinnamon extract against yeast α-glucosidase with the IC 50 value of 5.83 μg/ml and mammalian α-glucosidase with IC 50 value of 670 μg/ml. Enzyme kinetics data fit to LB plot pointed out competitive mode of inhibition and the membrane dialysis experiment revealed reversible nature of inhibition. In vivo animal experiments are indicative of ameliorated postprandial hyperglycemia as the oral intake of the cinnamon extract (300 mg/kg body wt.) significantly dampened the postprandial hyperglycemia by 78.2% and 52.0% in maltose and sucrose

Michael Thonet

Index Scriptorium Estoniae

2005-01-01

Saksa päritolu austria mööblidisaineri ja mööblitöösturi Michael Thonet' (1796-1871) disainiloomingust. 1859. a. Michael Thonet' loodud tool nr. 14 on endiselt tootmises ja on tuntud ka Viini toolina. 2 ill

Authentication of true cinnamon (Cinnamon verum) utilising direct analysis in real time (DART)-QWToF-MS

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The use of cinnamon as a spice and 'avouring agent is widespread throughout the world. Many different species of plants are commonly referred to as ‘cinnamon’. ‘True cinnamon’ refers to the dried inner bark of Cinnamomum verum J. S. Presl (syn. C zeylanicum) (Lauraceae). Other ‘cinnamon’ species, C....

Synthesis and spectroscopic characterization of a fluorescent pyrrole derivative containing electron acceptor and donor groups

Science.gov (United States)

Almeida, A. K. A.; Monteiro, M. P.; Dias, J. M. M.; Omena, L.; da Silva, A. J. C.; Tonholo, J.; Mortimer, R. J.; Navarro, M.; Jacinto, C.; Ribeiro, A. S.; de Oliveira, I. N.

2014-07-01

The synthesis and fluorescence characterization of a new pyrrole derivative (PyPDG) containing the electron donor-acceptor dansyl substituent is reported. The effects of temperature and solvent polarity on the steady-state fluorescence of this compound are investigated. Our results show that PyPDG exhibits desirable fluorescent properties which makes it a promising candidate to be used as the photoactive material in optical thermometry and thermography applications. Further, the electrochemical and emission properties of polymeric films obtained from the oxidation polymerization of PyPDG are also analyzed.

Cinnamon extract improves insulin sensitivity in the brain and lowers liver fat in mouse models of obesity.

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Sartorius, Tina; Peter, Andreas; Schulz, Nadja; Drescher, Andrea; Bergheim, Ina; Machann, Jürgen; Schick, Fritz; Siegel-Axel, Dorothea; Schürmann, Annette; Weigert, Cora; Häring, Hans-Ulrich; Hennige, Anita M

2014-01-01

Treatment of diabetic subjects with cinnamon demonstrated an improvement in blood glucose concentrations and insulin sensitivity but the underlying mechanisms remained unclear. This work intends to elucidate the impact of cinnamon effects on the brain by using isolated astrocytes, and an obese and diabetic mouse model. Cinnamon components (eugenol, cinnamaldehyde) were added to astrocytes and liver cells to measure insulin signaling and glycogen synthesis. Ob/ob mice were supplemented with extract from cinnamomum zeylanicum for 6 weeks and cortical brain activity, locomotion and energy expenditure were evaluated. Insulin action was determined in brain and liver tissues. Treatment of primary astrocytes with eugenol promoted glycogen synthesis, whereas the effect of cinnamaldehyde was attenuated. In terms of brain function in vivo, cinnamon extract improved insulin sensitivity and brain activity in ob/ob mice, and the insulin-stimulated locomotor activity was improved. In addition, fasting blood glucose levels and glucose tolerance were greatly improved in ob/ob mice due to cinnamon extracts, while insulin secretion was unaltered. This corresponded with lower triglyceride and increased liver glycogen content and improved insulin action in liver tissues. In vitro, Fao cells exposed to cinnamon exhibited no change in insulin action. Together, cinnamon extract improved insulin action in the brain as well as brain activity and locomotion. This specific effect may represent an important central feature of cinnamon in improving insulin action in the brain, and mediates metabolic alterations in the periphery to decrease liver fat and improve glucose homeostasis.

Effect of cinnamon powder addition to a Portuguese custard tart (Pastel de Nata) on healthy adults' postprandial glycemia

OpenAIRE

Moncada, Margarida Maria; Bernardo, Ma; Silva, M.L.; Jorge, A.; Pereira, P.; Brito, J.; Singh, Jaipaul; Mesquita, M.F.

2017-01-01

Background and Objective: Cinnamon is a spice used over the years in cooking to impart aromatic, flavor and taste properties to food and beverages. Moreover, cinnamon has been used for its medicinal properties due to its potential phenolic content, which can protect against cardio-metabolic diseases. Previous studies reported an improvement of postprandial glycemia after addition of cinnamon powder to a high-sugar meal. The study aims at investigating the effect of adding cinnamon powder to a...

Effect of gamma radiation on fungi contaminating powdered cinnamon

International Nuclear Information System (INIS)

EL-Bazza, Z.E.

1988-01-01

Thirty fungal organisms were isolated from ten samples of powdered cinnamon. These fungal cultures, identified as aspergillus and penicillium sp., Were screened for aflatoxins B 1, B 2, G 1 and G 2 production. One isolate could produce aflatoxin B 1 and identified as aspergillus flavus. The D 1 0 value for this strain of aspergillus flavus was 0.35 kGy in aqueous suspension. The dose level of 4 kGy was found to be sufficient for decontamination of fungi present on one batch of powdered cinnamon investigated. This dose is within the accepted irradiation dose mentioned by the joint FAO/IAEA/WHO expert committee on irradiated foods

Beneficial Effects of Cinnamon on the Metabolic Syndrome, Inflammation, and Pain, and Mechanisms Underlying These Effects – A Review

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Shen, Yan; Jia, Liu-Nan; Honma, Natsumi; Hosono, Takashi; Ariga, Toyohiko; Seki, Taiichiro

2012-01-01

Cinnamon is one of the most important herbal drugs and has been widely used in Asia for more than 4000 years. As a folk medicine, cinnamon has been traditionally applied to the treatment of inflammatory disorders and gastric diseases. After chemical profiling of cinnamon's components, their biological activities including antimicrobial, antiviral, antioxidant, antitumor, antihypertension, antilipemic, antidiabetes, gastroprotective and immunomodulatory were reported by many investigators. As a result, current studies have been performed mostly focusing on the bioactivity of cinnamon toward the recently generalized metabolic syndrome involving diabetes. In this review article, we provide an overview of the recent literature describing cinnamon's potential for preventing the metabolic syndrome. PMID:24716111

Tetrabutylammonium Bromide Media Aza-Michael Addition of 1,2,3,6-Tetrahydrophthalimide to Symmetrical Fumaric Esters and Acrylic Esters under Solvent-Free Conditions

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Mohammadreza Zamanloo

2010-10-01

Full Text Available The aza-Michael addition of 1,2,3,6-tetrahydrophthalimide with symmetrical fumaric esters has been performed efficiently in a solvent-free system at 100 °C and using 1,4-diazabicyclo[2.2.2]octane (DABCO as a base in the presence of tetrabutylammonium bromide (TBAB. The products were obtained in good to high yields within 2.5-7.0 h. This reaction worked well on linear alkyl fumarates and was not effective with nonlinear alkyl fumarates. Although the reaction was also applicable to acrylates such as n-butyl acrylate, methacrylates and crotonates were not suitable Michael acceptors for this reaction.

Jack Michael's Motivation

OpenAIRE

Miguel, Caio F.

2013-01-01

Among many of Jack Michael's contributions to the field of behavior analysis is his behavioral account of motivation. This paper focuses on the concept of motivating operation (MO) by outlining its development from Skinner's (1938) notion of drive. Conceptually, Michael's term helped us change our focus on how to study motivation by shifting its origins from the organism to the environment. Michael's account also served to stimulate applied research and to better understand behavioral functio...

Effects of allspice, cinnamon, and clove bud essential oils in edible apple films on physical properties and antimicrobial activities.

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Du, W-X; Olsen, C W; Avena-Bustillos, R J; McHugh, T H; Levin, C E; Friedman, Mendel

2009-09-01

Essential oils (EOs) derived from plants are rich sources of volatile terpenoids and phenolic compounds. Such compounds have the potential to inactivate pathogenic bacteria on contact and in the vapor phase. Edible films made from fruits or vegetables containing EOs can be used commercially to protect food against contamination by pathogenic bacteria. EOs from cinnamon, allspice, and clove bud plants are compatible with the sensory characteristics of apple-based edible films. These films could extend product shelf life and reduce risk of pathogen growth on food surfaces. This study evaluated physical properties (water vapor permeability, color, tensile properties) and antimicrobial activities against Escherichia coli O157:H7, Salmonella enterica, and Listeria monocytogenes of allspice, cinnamon, and clove bud oils in apple puree film-forming solutions formulated into edible films at 0.5% to 3% (w/w) concentrations. Antimicrobial activities were determined by 2 independent methods: overlay of the film on top of the bacteria and vapor phase diffusion of the antimicrobial from the film to the bacteria. The antimicrobial activities against the 3 pathogens were in the following order: cinnamon oil > clove bud oil > allspice oil. The antimicrobial films were more effective against L. monocytogenes than against the S. enterica. The oils reduced the viscosity of the apple solutions and increased elongation and darkened the colors of the films. They did not affect water vapor permeability. The results show that apple-based films with allspice, cinnamon, or clove bud oils were active against 3 foodborne pathogens by both direct contact with the bacteria and indirectly by vapors emanating from the films.

Sensory Attributes and Preliminary Characterization of Milk Chocolate Bar Enriched with Cinnamon Essential Oil

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Ilmi, A.; Praseptiangga, D.; Muhammad, D. R. A.

2017-04-01

Cocoa (Theobroma cacao) is one of Indonesia's main commodities with annually increasing production. Chocolates are semi-solid suspensions of fine solid particles in a continuous fat phase. Primary chocolate categories are dark, milk, and white that differs in content of cocoa solid, milk fat, and cocoa butter. Milk chocolate bar is one of the most popular processed cocoa products in Indonesia. Widely cultivated in Indonesia, cinnamon is potential to be developed and is expected to add flavor and taste as well as enhance functional properties of milk chocolate, since it is well-known of its high antioxidant properties. The aim of this study was to determine the effect of cinnamon essential oil addition on the sensory attributes and physicochemical properties of milk chocolate bar. Three formulas of milk chocolate bar with an addition of cinnamon essential oil (0.1%, 0.3%, and 0.5%) were evaluated in this study. Panelists acceptance level decreased with increasing concentrations of cinnamon essential oil added, while moisture content and color analysis results did not show any significantly different for each formula, suggesting that milk chocolate bar with the addition of 0.1% of cinnamon essential oil had the highest level of acceptance and preferences for some of properties evaluated.

Radioactivity level of different cinnamon samples

Energy Technology Data Exchange (ETDEWEB)

Czegledi, P; Cieleszky, V [Institut of Nutrition, Budapest (Hungry); Andrasi, A; Zombori, P [Koezponti Fizikai Kutato Intezet, Budapest (Hungary)

1980-06-01

/sup 40/K, /sup 90/Sr, /sup 137/Cs, /sup 226/Ra, and /sup 232/Th were determined in cinnamon samples from China, Sri Lanka and Indonesia. The Chinese sample contained an extremenly high quantity of /sup 90/Sr and its /sup 137/Cs content was also considerably higher than that of the other samples.

Physical characteristics of cinnamon oil microcapsule

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Hermanto, R. F.; Khasanah, L. U.; Kawiji; Atmaka, W.; Manuhara, G. J.; Utami, R.

2016-02-01

Cinnamon (Cinnamomum burmanii) oil products can be obtained from the bark by steam distillation. Essential oils are susceptible to high temperatures, oxidation, UV light, and humidity. Microencapsulation may change essential oils into powder, protect the sensitive core material and reduce the amount of flavor which lost during storage. In the microencapsulation, one of the important factors is the type of coating agent. The objective of this work was to characterize the cinnamon oil microcapsule. Ratio variations of coating agent maltodextrin and gum arabic were (1:0); (0:1); (1:1); (2:3). Physical characteristics such as water content, solubility, bulk density, surface oil, and microencapsulation efficiency of samples were investigated. Results showed that the ratio variations of the coating agent significantly affected the water content, bulk density, surface oil and microencapsulation efficiency but significantly affected the water solubility. Characteristics of selected microcapsule were 6.13% water content; 96.33% solubility; 0.46 g/cm3 bulk density; 2.68% surface oil; 70.68% microencapsulation efficiency and microstructures were rather good.

Improving Indonesian cinnamon (c. burmannii (Nees & t. nees) Blume) value chains for Greater Farmers Incomes

Science.gov (United States)

Menggala, S. R.; Damme, P. V.

2018-03-01

Genus Cinnamomum (Lauraceae) regroups some species whose stem bark are harvested, conditioned and traded as cinnamon in an international market. Over the centuries, the species have been domesticated so that now at least six different ones are grown in Southeast Asia countries. One of the species is Cinnamomum burmannii, also known as Korintje Cinnamon, which generates income for most smallholder farmers in Kerinci district, Jambi, Indonesia. Most cinnamon consumed in the world originates from this Korintje Cinnamon products. It is recognized for its unparalleled quality that comes with its sharp and sweet flavor, with a slightly bitter edge. However, international market requirements for product certification and quality standards make it difficult for a farmer to comply. Our research will address issues related to (improvement of) productivity, sustainability and value chains faced by cinnamon producers in Kerinci, to strengthen their product’s value chains. Smallholder farmers are very vulnerable to climate change impacts, and thus empowering the value chains of agricultural products will increase farmers resilience to climate change. The research will analyze the development of agricultural value chains, certification & standards on trade mechanism to help farmers earn a better income and future prospects.

[Cinnamon rolls are not associated with admission for toxic or alcoholic hepatitis in a Danish liver referral centre].

Science.gov (United States)

Gr Ønbæk, Henning; Borre, Mette

2014-12-08

Cinnamon contains cumarin, which may be toxic to the liver. EU-regulations standardardize the amount of cinnamon in pastry including cinnamon rolls. The aim of the study was to investigate if cinnamon intake from pastry was associated with toxic or alcoholic hepatitis. We registered 58 patients with toxic hepatitis, 38 (66%) women and 20 (34%) men with a median age of 51 (range: 32-80) and 53 (range: 18-78) years, respectively. A total of 22 patients had primarily cholestasis and 36 had hepatitis biochemically. The duration of toxic liver disease from admission to normalization of liver enzymes was similar in the two groups (3.5 ± 3.5 vs 3.6 ± 3.5 months). Toxic hepatitis was most often caused by drugs e.g. NSAID (n = 15; 26%), antibiotics (n = 9; 16%), alternative medicine (n = 7; 12%) and Antabuse (n = 5; 9%). We registered eight patients admitted with severe alcoholic hepatitis, five men and three women, median age of 60 (range: 34-67) years. Alcoholic hepatitis was associated with high alcohol intake. None of the patients with toxic or alcoholic hepatitis reported of excessive intake of cinnamon rolls and there was no evidence of cinnamon added to alcohol of alternative medicine products. Intake of cinnamon from cinnamon rolls is not associated with admission for toxic or alcoholic hepatitis. However, for the diagnosis of toxic liver diseases including alcohol it is very important to have patient information regarding any new drugs, alternative medicine and alcohol intake. Further, other causes of liver diseases should be excluded. not relevant. not relevant.

Radical unique to gamma-irradiated allspice and cinnamon and its utiliy for detection of irradiated foods

Energy Technology Data Exchange (ETDEWEB)

Uchiyama, S. [National Inst. of Hygienic Sciences, Tokyo (Japan); Sugiki, A.; Kawamura, Y.; Murayama, M.; Saito, Y.

1993-04-15

Gamma-Irradiation at a practical dose level of allspice and cinnamon generates a principal signal (signal I, g-value: 2.0048 approx 2.0050) and a minor signal (signal II) at 30 G lower field from signal I in the electron spin resonance spectrum. Signal I, which was not increased in red pepper by photo-exposure, was increased in allspice and cinnamon by gamma-irradiation, heating and even photo-exposure. Signal II was generated only by gamma-irradiation, was little influenced by humidity and was stable for a long time. The ESR method with signal II was applicable to detection of allspice and cinnamon irradiated at 5 kGy or more for up to 6 months after irradiation, as well as allspice irradiated at 10 kGy or more and cinnamon at 5 kGy or more for up to a year. However, signal intensities of signal II differed to some extent between allspice and cinnamon, and even between varieties of cinnamon. Signals I and II were both enhanced after extraction with methanol. Since the rate of increase in signal I was obviously distinct from that of signal II, the radicals corresponding to these signals were presumed to be located at different positions of the matrix of the spice. The methanolic extracts did not yield a major component common to the spices giving signal II.

Cinnamon Oil and Chitosan Coating on Orthopaedic Implant Surface for Prevention of Staphylococcus Epidermidis Biofilm Formation

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R Magetsari

2014-11-01

Full Text Available S. Epidermidis is among the most frequently isolated microorganisms found in -infection related to implanted devices and the formation of biofilm will be more resistantcompared to the planktonic form. This study was carried out determine the effect of coating on stainless steel orthopaedic implants surfaces with cinnamon oil and chitosan as bioadhesive to prevent biofilms formation of S. Epidermidis.The rod shaped stainless steel 316 L orthopaedic implant with 5 mm diameters was coated 2 times using a mixture of cinnamon oil and chitosan 3% and 2% respectively with serial concentration of cinnamon from 0.125% to 2%. The coated implants were then put into tubes that contained bacterial suspension and incubated. Subsequently, the implants were washed with PBS solution followed by MTT soulution and isopropanol acid solution that related to biofilm formation. The results were expressed in numbers which represents the absorbance level at ELISA readings on 575 nm (A575 wavelength.The stainless steel implant coated with chitosan and cinnamon oil 2% and 1% has lower absorbance level compared with the absorbance level of S.Epidermidis biofilm only. This study showed that mixture of cinnamon oil and chitosan coated on the surface of stainless steel orthopaedic implant has an effect against S.Epidermidis biofilm formation with minimum cinnamon oil concentration of 1%.

Applications of the Addition of extract and cinnamon leaf flour in the Diet on the Quality of Meat of Catfish

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Suardi Laheng

2016-04-01

Full Text Available This study aimed to evaluate the effect of extract and cinnamon (Cinnamomum burmannii leaf flour in the diet in increasing quality of meat of catfish (Pangsianodon hypopthalmus. Catfish with a weight of 319.64 ± 35.99 g/nets reared in 9 nets with dimension 2x1x1,5 m3 at a density of 15 fish/nets for 60 days of maintenance. The fish were fed with leaves of cinnamon at a dose that was: 0% cinnamon leaf, 0.1% cinnamon leaf extract, and 1% cinnamon leaf flour. The fish were fed 2 times a day with the feeding rate of 3% of the average weight of the body. The results showed the treatment of leaf extract and flour, cinnamon capable of decreasing levels of body fat, fat meat by 10,31-12,27%, 37,26-50,23%, respectively, compared to controls (p<0,05, however, cinnamon leaf extract treatment is more effective in improving the quality of meat catfish that looks meat texture compact, white flesh color and a slightly sweet taste.

Applications of the Addition of extract and cinnamon leaf flour in the Diet on the Quality of Meat of Catfish

Directory of Open Access Journals (Sweden)

Suardi Laheng

2016-04-01

Full Text Available This study aimed to evaluate the effect of extract and cinnamon (Cinnamomum burmannii leaf flourin the diet in increasing quality of meat of catfish (Pangsianodon hypopthalmus. Catfish with a weight of319.64 ± 35.99 g/nets reared in 9 nets with dimension 2x1x1,5 m3 at a density of 15 fish/nets for 60 daysof maintenance. The fish were fed with leaves of cinnamon at a dose that was: 0% cinnamon leaf, 0.1%cinnamon leaf extract, and 1% cinnamon leaf flour. The fish were fed 2 times a day with the feeding rate of3% of the average weight of the body. The results showed the treatment of leaf extract and flour, cinnamoncapable of decreasing levels of body fat, fat meat by 10,31-12,27%, 37,26-50,23%, respectively, compared tocontrols (p<0,05, however, cinnamon leaf extract treatment is more effective in improving the quality ofmeat catfish that looks meat texture compact, white flesh color and a slightly sweet taste.Keywords: cinnamon leaf, meat quality, Pangsianodon hypopthalmus

Michael Griffin | NREL

Science.gov (United States)

Griffin Photo of Michael Griffin Michael Griffin Researcher III-Chemical Engineering production of high-value products Physical and chemical material characterization under reaction conditions Physical and chemical characterization of catalytic materials Surface science Design and operation of ultra

Structure and electronic properties of Alq3 derivatives with electron acceptor/donor groups at the C4 positions of the quinolate ligands: a theoretical study.

Science.gov (United States)

Rao, Joshi Laxmikanth; Bhanuprakash, Kotamarthi

2011-12-01

The molecular structures of the ground (S(0)) and first singlet excited (S(1)) states of Alq3 derivatives in which pyrazolyl and 3-methylpyrazolyl groups are substituted at the C4 positions of the 8-hydroxyquinolate ligands as electron acceptors, and piperidinyl and N-methylpiperazinyl groups are substituted at the same positions as electron donors, have been optimized using the B3LYP/6-31G and CIS/6-31G methods, respectively. In order to analyze the electronic transitions in these derivatives, the frontier molecular orbital characteristics were analyzed systematically, and it was found that the highest occupied molecular orbital is localized on the A ligand while the lowest unoccupied molecular orbital is localized on the B ligand in their ground states, similar to what is seen for mer-Alq3. The absorption and emission spectra were evaluated at the TD-PBE0/6-31G level, and it was observed that electron acceptor substitution causes a red-shift in the emission spectra, which is also seen experimentally. The reorganization energies were calculated at the B3LYP/6-31G level and the results show that acceptor/donor substitution has a significant effect on the intrinsic charge mobilities of these derivatives as compared to mer-Alq3.

Formulation of vitamin D encapsulated cinnamon oil nanoemulsion: Its potential anti-cancerous activity in human alveolar carcinoma cells.

Science.gov (United States)

Meghani, Nikita; Patel, Pal; Kansara, Krupa; Ranjan, Shivendu; Dasgupta, Nandita; Ramalingam, Chidambaram; Kumar, Ashutosh

2018-06-01

Cinnamon oil is used for medicinal purpose since ancient time because of its antioxidant activity. Oil-in-water nanoemulsion (NE) of cinnamon oil was formulated using cinnamon oil, nonionic surfactant Tween 80 and water by ultrasonication technique. Phase diagram was constructed to investigate the influence of oil, water and surfactant concentration. Vitamin D encapsulated cinnamon oil NE was fabricated by wash out method followed by ultrasonication in similar fashion. The hydrodynamic size of cinnamon oil NE and vitamin D encapsulated cinnamon oil NE was observed as 40.52 and 48.96 nm in complete DMEM F12 media respectively. We focused on the cytotoxic and genotoxic responses of NEs in A549 cells in concentration dependent manner. We observed that both NEs induce DNA damage along with corresponding increase in micronucleus frequency that is evident from the comet and CBMN assay. Both the NEs arrested the cell cycle progression in G0/G1 phase, showed increased expression of Bax, capase-3 and caspase-9 and decrease expression of BcL2 proteins along with significant (p oil as carrier for lipophilic nutraceutical like vitamin D. Copyright © 2018 Elsevier B.V. All rights reserved.

Cinnamon users with prediabetes have a better fasting working memory: a cross-sectional function study.

Science.gov (United States)

Wahlqvist, Mark L; Lee, Meei-Shyuan; Lee, Jiunn-Tay; Hsu, Chih-Cheng; Chou, Yu-Ching; Fang, Wen-Hui; Liu, Hsiao-Yu; Xiu, Lili; Andrews, Zane B

2016-04-01

Working memory (WM) is impaired in prediabetes. We hypothesized that culinary herbs and spices may decrease insulin resistance (IR) and improve WM in prediabetes. Healthy people aged ≥60 years with prediabetes (fasting blood glucose 100-125 mg/dL) (47 men and 46 women) whose food and culinary herb intakes were established with a food frequency questionnaire had body composition assessed and fasting glucose and insulin measured. Working memory and Mini-Mental State Examination (MMSE) were assessed on the same occasion. The contributions to associations between WM and diet, body fat, and IR were estimated by linear regression. Compared with nonusers, cinnamon users had significantly less frequent physical activity (2.9 vs. 4.4 times per week) and more often used fresh ginger (93.3% vs. 64.1%) and ginger in cooking (60.0% vs. 32.1%). Cinnamon users also had a better WM (2.9 vs. 2.5, P < .001). Cinnamon had a significant effect (users were 0.446 higher), but not ginger or curry usage, in predicting WM. For sociodemographic variables, only education (years) was significant in predicting WM (β = 0.065). Other significant determinants of WM were total fat mass (kilograms) (β = -0.024) and MMSE (β = 0.075). After adjustment for age and sex, cinnamon use, education, and MMSE remained significant individual predictors. In the final model, in which all variables listed were adjusted simultaneously, cinnamon users still had a significantly higher WM than nonusers. Cinnamon usage is associated with a better WM, not accounted for by dietary quality or IR, in untreated prediabetes. Copyright © 2016 Elsevier Inc. All rights reserved.

Application of Cinnamon oil Nanoemulsion to Control Foodborne Bacteria such as Listeria Sp. and Salmonella Sp. On Melons

Science.gov (United States)

Paudel, Sumit Kumar

Listeria and Salmonella related recalls and outbreaks are of major concern to the melon industry. Cinnamon oil has shown its usefulness in food treatment due to strong antifungal, antiviral, and antibacterial activities. However, its applications are limited due to poor solubility of cinnamon oil in water. Utilization of Cinnamon oil nanoemulsion may offer effective antimicrobial washing treatment to melon industry. The purpose of this study was to test the antimicrobial efficacy of cinnamon oil nanoemulsion on melons against major food borne pathogens such as Listeria monocytogenes and Salmonella enterica. Different formulations of cinnamon oil nanoemulsion were made by ultrasonication using Tween 80 as an emulsifier. Nanoemulsion exhibiting the smallest oil droplets was applied. Oil droplets were characterized for particle size by dynamic light scattering. Microbroth dilution assay was performed on three strains each of Listeria monocytogenes and Salmonella enterica to find out the antimicrobial efficacy of cinnamon oil nanoemulsion. Honeydew and cantaloupe were artificially inoculated with the strains mentioned above followed by treatment in nanoemulsion (control, 0.1%, 0.25%, and 0.5%) for one minute. Samples were dried and enumerated after one hour of treatment on selective media (PALCAM and XLD agar). The average diameter of nanoemulsion was 9.63+/-0.3nm. Minimum inhibitory concentration (MIC) of cinnamon oil nanoemulsion for both Listeria and Salmonella strains was 0.078% v/v and 0.039% v/v, respectively and the minimum bactericidal concentration was 0.078125% v/v for both. Compared to the water control, 0.5% nanoemulsion showed up to 7.7 and 5.5 log CFU/gm reductions in L. monocytogenes and S. enterica, respectively. The data suggests that cinnamon oil nanoemulsion can be used as an effective natural microbial control agent for melons. Keywords: Nanoemulsion, ultrasonication, antimicrobial.

A facile and efficient method of enzyme immobilization on silica particles via Michael acceptor film coatings: immobilized catalase in a plug flow reactor.

Science.gov (United States)

Bayramoglu, Gulay; Arica, M Yakup; Genc, Aysenur; Ozalp, V Cengiz; Ince, Ahmet; Bicak, Niyazi

2016-06-01

A novel method was developed for facile immobilization of enzymes on silica surfaces. Herein, we describe a single-step strategy for generating of reactive double bonds capable of Michael addition on the surfaces of silica particles. This method was based on reactive thin film generation on the surfaces by heating of impregnated self-curable polymer, alpha-morpholine substituted poly(vinyl methyl ketone) p(VMK). The generated double bonds were demonstrated to be an efficient way for rapid incorporation of enzymes via Michael addition. Catalase was used as model enzyme in order to test the effect of immobilization methodology by the reactive film surface through Michael addition reaction. Finally, a plug flow type immobilized enzyme reactor was employed to estimate decomposition rate of hydrogen peroxide. The highly stable enzyme reactor could operate continuously for 120 h at 30 °C with only a loss of about 36 % of its initial activity.

Michael E. Himmel | NREL

Science.gov (United States)

E. Himmel Photo of Michael E. Himmel Michael Himmel Senior Research Fellow I-Molecular Biology biochemistry, recombinant technology, enzyme engineering, new micro-organism discovery, and physicochemistry of

Novel Terthiophene-Substituted Fullerene Derivatives as Easily Accessible Acceptor Molecules for Bulk-Heterojunction Polymer Solar Cells

Directory of Open Access Journals (Sweden)

Filippo Nisic

2014-01-01

Full Text Available Five fulleropyrrolidines and methanofullerenes, bearing one or two terthiophene moieties, have been prepared in a convenient way and well characterized. These novel fullerene derivatives are characterized by good solubility and by better harvesting of the solar radiation with respect to traditional PCBM. In addition, they have a relatively high LUMO level and a low band gap that can be easily tuned by an adequate design of the link between the fullerene and the terthiophene. Preliminary results show that they are potential acceptors for the creation of efficient bulk-heterojunction solar cells based on donor polymers containing thiophene units.

Highly Functionalized Cyclopentane Derivatives by Tandem Michael Addition/Radical Cyclization/Oxygenation Reactions

Czech Academy of Sciences Publication Activity Database

Holan, Martin; Pohl, Radek; Císařová, I.; Klepetářová, Blanka; Jones, P. G.; Jahn, Ullrich

2015-01-01

Roč. 21, č. 27 (2015), s. 9877-9888 ISSN 0947-6539 R&D Projects: GA ČR GA13-40188S Institutional support: RVO:61388963 Keywords : cyclization * domino reactions * electron transfer * Michael addition * radical reactions Subject RIV: CC - Organic Chemistry Impact factor: 5.771, year: 2015

Effect of cortisol on gonadotropin inhibitory hormone (GnIH) in the cinnamon clownfish, Amphiprion melanopus.

Science.gov (United States)

Choi, Young Jae; Habibi, Hamid R; Kil, Gyung-Suk; Jung, Min-Min; Choi, Cheol Young

2017-04-01

Hypothalamic peptides, gonadotropin-releasing hormone (GnRH) and gonadotropin inhibitory hormone (GnIH), play pivotal roles in the control of reproduction and gonadal maturation in fish. In the present study we tested the possibility that stress-mediated reproductive dysfunction in teleost may involve changes in GnRH and GnIH activity. We studied expression of brain GnIH, GnIH-R, seabream GnRH (sbGnRH), as well as circulating levels of follicle stimulating hormone (FSH), and luteinizing hormone (LH) in the cinnamon clownfish, Amphiprion melanopus. Treatment with cortisol increased GnIH mRNA level, but reduced sbGnRH mRNA and circulating levels of LH and FSH in cinnamon clownfish. Using double immunofluorescence staining, we found expression of both GnIH and GnRH in the diencephalon region of cinnamon clownfish brain. These findings support the hypothesis that cortisol, an indicator of stress, affects reproduction, in part, by increasing GnIH in cinnamon clownfish which contributes to hypothalamic suppression of reproductive function in A. melanopus, a protandrous hermaphroditic fish. Copyright © 2017 Elsevier Inc. All rights reserved.

Effect of cinnamon on gastric emptying, arterial stiffness, postprandial lipemia, glycemia, and appetite responses to high-fat breakfast

Directory of Open Access Journals (Sweden)

Trinick Tom R

2011-09-01

Full Text Available Abstract Background Cinnamon has been shown to delay gastric emptying of a high-carbohydrate meal and reduce postprandial glycemia in healthy adults. However, it is dietary fat which is implicated in the etiology and is associated with obesity, type 2 diabetes and cardiovascular disease. We aimed to determine the effect of 3 g cinnamon (Cinnamomum zeylanicum on GE, postprandial lipemic and glycemic responses, oxidative stress, arterial stiffness, as well as appetite sensations and subsequent food intake following a high-fat meal. Methods A single-blind randomized crossover study assessed nine healthy, young subjects. GE rate of a high-fat meal supplemented with 3 g cinnamon or placebo was determined using the 13C octanoic acid breath test. Breath, blood samples and subjective appetite ratings were collected in the fasted and during the 360 min postprandial period, followed by an ad libitum buffet meal. Gastric emptying and 1-day fatty acid intake relationships were also examined. Results Cinnamon did not change gastric emptying parameters, postprandial triacylglycerol or glucose concentrations, oxidative stress, arterial function or appetite (p half and 1-day palmitoleic acid (r = -0.78, eiconsenoic acid (r = -0.84 and total omega-3 intake (r = -0.72. The ingestion of 3 g cinnamon had no effect on GE, arterial stiffness and oxidative stress following a HF meal. Conclusions 3 g cinnamon did not alter the postprandial response to a high-fat test meal. We find no evidence to support the use of 3 g cinnamon supplementation for the prevention or treatment of metabolic disease. Dietary fatty acid intake requires consideration in future gastrointestinal studies. Trial registration Trial registration number: at http://www.clinicaltrial.gov: NCT01350284

Conformational dynamics of semiflexibly bridged electron donor-acceptor systems comprising long aliphatic tails

NARCIS (Netherlands)

Bleisteiner, B.; Marian, T.; Schneider, S.; Brouwer, A.M.; Verhoeven, J.W.

2001-01-01

In continuation of our previous work on the conformational dynamics (harpooning mechanism) of semiflexibly bridged electron donor-acceptor systems we have studied a derivative with two long aliphatic chains tethered to the donor and acceptor moieties, respectively. The fitting of the time- and

Donor-Acceptor Block Copolymers: Synthesis and Solar Cell Applications

Directory of Open Access Journals (Sweden)

Kazuhiro Nakabayashi

2014-04-01

Full Text Available Fullerene derivatives have been widely used for conventional acceptor materials in organic photovoltaics (OPVs because of their high electron mobility. However, there are also considerable drawbacks for use in OPVs, such as negligible light absorption in the visible-near-IR regions, less compatibility with donor polymeric materials and high cost for synthesis and purification. Therefore, the investigation of non-fullerene acceptor materials that can potentially replace fullerene derivatives in OPVs is increasingly necessary, which gives rise to the possibility of fabricating all-polymer (polymer/polymer solar cells that can deliver higher performance and that are potentially cheaper than fullerene-based OPVs. Recently, considerable attention has been paid to donor-acceptor (D-A block copolymers, because of their promising applications as fullerene alternative materials in all-polymer solar cells. However, the synthesis of D-A block copolymers is still a challenge, and therefore, the establishment of an efficient synthetic method is now essential. This review highlights the recent advances in D-A block copolymers synthesis and their applications in all-polymer solar cells.

Effect of Gamma Irradiation on Chemical Constituents, Antimicrobials and Antioxidants of Thyme and Cinnamon Volatile Oils

International Nuclear Information System (INIS)

Anwar, M.M.; Nasr, E.H.; Ali, S.E.

2015-01-01

This study was carried out to investigate the effect of gamma irradiation at doses 10 or 20 kGy on the chemical constituents of essential oils extracted from irradiated thyme and cinnamon, and study the effect of these essential oils on the oxidative stability of soybean oil. In addition, this study was carried out to evaluate the efficacy of extracted essential oils from irradiated thyme and cinnamon as Antimicrobial agents.The results showed that the major components for essential oils of thyme were 77.03% thymol and 15.34 % eugenol acetate whereas the major components for essential oils of cinnamon were 66.14% cinnamaldehyde and 11.18% cinnamyl cinnamate. The study revealed that the essential oils extracted from irradiated cinnamon at 20 kGy showed the best antioxidant activities while gamma irradiation reduced the antioxidant activities of thyme essential oils. Essential oils extracted from irradiated and non-irradiated thyme and cinnamon were tested for the antibacterial activities against eight strains of Salmonella spp., Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, Pseudomonas citri, Pseudomonas aeruginosa, Bacillus cereus and Bacillus subtilis and also tested for their antifungal activities against four strains of Penicillium spp., Rhizopus spp., Alternaria alternata and Aspergillus niger. The results showed that all tested oils exhibited an inhibition effect for the growth of the microorganisms under investigation and gamma irradiation at dose 20 kGy had the high effect.

Influence of ginger and cinnamon intake on inflammation and muscle soreness endued by exercise in Iranian female athletes

Directory of Open Access Journals (Sweden)

Nafiseh Shokri Mashhadi

2013-01-01

Conclusions: Administration of ginger and cinnamon in athlete women for six weeks did not show any significant change in the IL-6 level, but showed a decrease in muscle soreness in the cinnamon and ginger groups.

Antioxidant capacity of cinnamon extract for palm oil stability.

Science.gov (United States)

Shahid, Muhammad Zia; Saima, Hafiza; Yasmin, Adeela; Nadeem, Muhammad Tahir; Imran, Muhammad; Afzaal, Muhammad

2018-05-16

Spices and their bioactive components are more promising attractions for their inclusion in diet-based regimes to improve human health. These are sources of natural antioxidants and play an important role in the chemoprevention of diseases and aging. The aim of the current study was to explore the antioxidant potential of cinnamon; a widely used spice throughout the world. The current research was aimed to investigate the antioxidant potential of cinnamon extract. For the purpose, cinnamon sticks were procured from local super market, while palm oil was obtained from local oil industry. The resultant extract was analyzed for its antioxidant activity through total phenolic content (TPC), free radical scavenging activity (DPPH assay), and total antioxidant activity was measured by ferric reducing antioxidant power (FRAP) test. The shelf life of palm oil was checked by adding cinnamon extract in oil at different levels i.e. , 0.05, 0.10, 0.15, 0.20 and 0.25%, to compare the antioxidant potential of the extract whereas, T o acted as control and T BHA @ 0.1% was used as synthetic antioxidant in the oil samples. The oil samples were analyzed for rancidity check during storage (after every seven days for a storage period of four weeks). The results indicated that total phenolic contents (TPC); 1,1-diphenyl-2-picrylhydrazyl (DPPH) and ferric reducing antioxidant power (FRAP) values of cinnamon extract were as 355.01 ± 8.34 gallic acid equivalent per gram (mg GAE/g), 90.18 ± 2.12 (%) and 132.82 ± 3.12 (μmol/g), respectively. The oxidative parameters for treatments i.e., T o , T BHA , T 1 , T 2 , T 3 , T 4 , T 5 were recorded as peroxide value (2.61 ± 0.07, 2.42 ± 0.08, 2.57 ± 0.05, 2.56 ± 0.03, 2.54 ± 0.02, 2.54 ± 0.01, 2.46 ± 0.06 meq/kg, respectively), free fatty acids (0.601 ± 0.05, 0.522 ± 0.02, 0.580 ± 0.07, 0.572 ± 0.03, 0.56 ± 00.07, 0.552 ± 0.03, 0.536 ± 0.05%, respectively), TBA

Effect of cinnamon on gastric emptying, arterial stiffness, postprandial lipemia, glycemia, and appetite responses to high-fat breakfast

LENUS (Irish Health Repository)

Markey, Oonagh

2011-09-07

Abstract Background Cinnamon has been shown to delay gastric emptying of a high-carbohydrate meal and reduce postprandial glycemia in healthy adults. However, it is dietary fat which is implicated in the etiology and is associated with obesity, type 2 diabetes and cardiovascular disease. We aimed to determine the effect of 3 g cinnamon (Cinnamomum zeylanicum) on GE, postprandial lipemic and glycemic responses, oxidative stress, arterial stiffness, as well as appetite sensations and subsequent food intake following a high-fat meal. Methods A single-blind randomized crossover study assessed nine healthy, young subjects. GE rate of a high-fat meal supplemented with 3 g cinnamon or placebo was determined using the 13C octanoic acid breath test. Breath, blood samples and subjective appetite ratings were collected in the fasted and during the 360 min postprandial period, followed by an ad libitum buffet meal. Gastric emptying and 1-day fatty acid intake relationships were also examined. Results Cinnamon did not change gastric emptying parameters, postprandial triacylglycerol or glucose concentrations, oxidative stress, arterial function or appetite (p < 0.05). Strong relationships were evident (p < 0.05) between GE Thalf and 1-day palmitoleic acid (r = -0.78), eiconsenoic acid (r = -0.84) and total omega-3 intake (r = -0.72). The ingestion of 3 g cinnamon had no effect on GE, arterial stiffness and oxidative stress following a HF meal. Conclusions 3 g cinnamon did not alter the postprandial response to a high-fat test meal. We find no evidence to support the use of 3 g cinnamon supplementation for the prevention or treatment of metabolic disease. Dietary fatty acid intake requires consideration in future gastrointestinal studies. Trial registration Trial registration number: at http:\\/\\/www.clinicaltrial.gov: NCT01350284

Oxidative markers, nitric oxide and homocysteine alteration in hypercholesterolimic rats: role of atorvastatine and cinnamon.

Science.gov (United States)

Amin, Kamal A; Abd El-Twab, Thanaa M

2009-10-05

To investigate the effects of atorvastatin and cinnamon on serum lipid profile, oxidative stress, antioxidant capacity, hepatic enzymes activities, nitric oxide (NO) as well as homocysteine (Hcy) in hypercholesterolemic rats, 48 male albino rats, weighing 130-190 gm were divided into 2 groups, normal group fed on basal rat chow diet (n=12) and high cholesterol group (HCD) were fed on 1% cholesterol-enriched diet for 15 day (n=36). Hypercholesterolemic rats were divided into 3 subgroups (n=12 for each) fed the same diet and treated with atorvastatine (HCD+Atorvastatin) or cinnamon extract (HCD+cinnamon) or none treated (HCD) for 3&6 weeks. Serum triglycerides (TG), Total cholesterol (TC), low density lipoprotein (LDL), high density lipoprotein (HDL), ALT, AST, NO, Hcy, hepatic reduced glutathione (GSH), Malondialdehyde (MDA) and antioxidant enzymes, Superoxide dismutase (SOD) and catalase activity were measured. Results showed that HCD increased significantly TG, TC, LDL-C, ALT, AST, Hcy and hepatic MDA, while lowered significantly antioxidant enzyme activities and NO levels. Atorvastatin therapy significantly increased HDL-C, NO and antioxidant activity while decreased LDL-C, MDA and Hcy concentrations. Serum TG, TC, LDL-C, ALT, AST and hepatic MDA levels were significantly lowered meanwhile, serum HDL, NO values and hepatic antioxidant activities were significantly, higher in cinnamon-treated than untreated group. These results indicate that lipid abnormalities, oxidative injury and hyperhomocystienemia were induced by HCD and this study recommend that administration of atorvastatine or cinnamon provided protection against the lipemic-oxidative disorder and act as hypocholesterolemic, hepatoprotective agent and improve cardiovascular function through modulation of oxidative stress, NO and Hcy.

Effect of ground cinnamon on postprandial blood glucose concentration in normal-weight and obese adults.

Science.gov (United States)

Magistrelli, Ashley; Chezem, Jo Carol

2012-11-01

In healthy normal-weight adults, cinnamon reduces blood glucose concentration and enhances insulin sensitivity. Insulin resistance, resulting in increased fasting and postprandial blood glucose and insulin levels, is commonly observed in obese individuals. The objective of the study was to compare declines in postprandial glycemic response in normal-weight and obese subjects with ingestion of 6 g ground cinnamon. In a crossover study, subjects consumed 50 g available carbohydrate in instant farina cereal, served plain or with 6 g ground cinnamon. Blood glucose concentration, the main outcome measure, was assessed at minutes 0, 15, 30, 45, 60, 90, and 120. Repeated-measures analysis of variance evaluated the effects of body mass index (BMI) group, dietary condition, and time on blood glucose. Paired t-test assessed blood glucose at individual time points and glucose area under the curve (AUC) between dietary conditions. Thirty subjects between the ages of 18 and 30 years, 15 with BMIs between 18.5 and 24.9 and 15 with BMIs of 30.0 or more, completed the study. There was no significant difference in blood glucose between the two BMI groups at any time point. However, in a combined analysis of all subjects, the addition of cinnamon to the cereal significantly reduced 120-minute glucose AUC (P=0.008) and blood glucose at 15 (P=0.001), 30 (Pblood glucose was significantly higher with cinnamon consumption (Pglucose response in normal weight and obese adults. Copyright © 2012 Academy of Nutrition and Dietetics. Published by Elsevier Inc. All rights reserved.

A comprehensive study of the optoelectronic properties of donor-acceptor based derivatives of 1,3,4-oxadiazole

Science.gov (United States)

Joshi, Ankita; Ramachandran, C. N.

2017-07-01

A variety of 1,3,4-oxadiazole derivatives based on electron- donor pyrrole and -acceptor nitro groups are modelled. Various isomers of pyrole-oxadiazole-nitro unit and its dimer linked to substituted and unsubstituted phenyl group are studied using the dispersion corrected density functional theoretical method. The electron density distribution in frontier orbitals of the phenyl-spacer compounds bearing amino and phenylamino groups indicates the possibility of intramolecular charge transfer. The isomers of phenyl-spacer compounds absorb in visible region of electromagnetic spectrum. The compounds show high values of light harvesting efficiency, despite the weak anchoring nature of nitro groups.

Recovery Profiles of T-Cell Subsets Following Low-Dose Total Body Irradiation and Improvement With Cinnamon

International Nuclear Information System (INIS)

Zheng, Xiaodan; Guo, Yuqi; Wang, Lei; Zhang, Honghai; Wang, Shaobo; Wang, Li; An, Lei; Zhou, Xianbin; Li, Xia; Yao, Chengfang

2015-01-01

Purpose: Inefficient T-cell reconstitution from x-ray–induced immune damage reduces antitumor response. To understand the profile of T-cell reconstitution after irradiation will overcome the barrier of antitumor immunity. This study aimed to identify the recovery profile of T-cell subsets following x-ray irradiation and to highlight the role of cinnamon on efficient T-cell restoration postexposure in the antitumor response. Methods and Materials: CD3"+, CD8"+, and CD4"+ T cells and Th1, Th2, Th17, and regulatory T (Treg) cells were evaluated at different time points after single low-dose total body irradiation (SLTBI) with or without cinnamon treatments. T-bet, GATA3, RORγt, and Foxp3 signaling specific for Th1, Th2, Th17, and Treg were also analyzed by RT-PCR assay. The effects of cinnamon on efficient T-cell subset reconstitution was confirmed in a lung melanoma model in irradiated mice. Results: Reconstitution of CD4"+ T cells was delayed more than that of CD8"+ T cells in T-cell restoration after SLTBI. The production of IFNγ by Th1 or Tc1 cells was sharply decreased and was accompanied by reduced T-bet mRNA, even when total T-cell numbers had recovered; the frequencies of Th17 and Treg cells and their specific transcription factors (RORγt and Foxp3, respectively) were obviously increased. Irradiation-induced inefficient T-cell reconstitution impaired the antitumor capacities in the lung melanoma model. Pretreatment with cinnamon in irradiated mice accelerated the generation of Th1 and reduced the differentiation of Treg cells by activating T-bet and limiting transcriptions of Foxp3. Improvement resulting from cinnamon pretreatment on the efficient T-cell recovery profile from SLTBI promoted antitumor immunity in the lung melanoma model. Conclusions: T-cell reconstitution from SLTBI was characterized by impaired Th1 and elevated Th17 and Treg cells. Cinnamon effectively improved the imbalance of T-cell subsets by promoting the proliferation of Th1 and

Recovery Profiles of T-Cell Subsets Following Low-Dose Total Body Irradiation and Improvement With Cinnamon

Energy Technology Data Exchange (ETDEWEB)

Zheng, Xiaodan [Key Laboratory for Tumor Immunology and Traditional Chinese Medicine Immunology, Institute of Basic Medicine, Shandong Academy of Medical Sciences, Jinan (China); School of Medicine and Life Science, University of Jinan-Shandong Academy of Medical Science, Jinan (China); Guo, Yuqi [Key Laboratory for Tumor Immunology and Traditional Chinese Medicine Immunology, Institute of Basic Medicine, Shandong Academy of Medical Sciences, Jinan (China); Wang, Lei [Second Affiliated Hospital of Shandong University of Traditional Chinese Medicine, Jinan (China); Zhang, Honghai [Key Laboratory for Tumor Immunology and Traditional Chinese Medicine Immunology, Institute of Basic Medicine, Shandong Academy of Medical Sciences, Jinan (China); Wang, Shaobo [Shandong University, Jinan (China); Wang, Li [Key Laboratory for Tumor Immunology and Traditional Chinese Medicine Immunology, Institute of Basic Medicine, Shandong Academy of Medical Sciences, Jinan (China); An, Lei [Key Laboratory for Tumor Immunology and Traditional Chinese Medicine Immunology, Institute of Basic Medicine, Shandong Academy of Medical Sciences, Jinan (China); School of Medicine and Life Science, University of Jinan-Shandong Academy of Medical Science, Jinan (China); Zhou, Xianbin; Li, Xia [Key Laboratory for Tumor Immunology and Traditional Chinese Medicine Immunology, Institute of Basic Medicine, Shandong Academy of Medical Sciences, Jinan (China); Yao, Chengfang, E-mail: yaocf9941@163.com [Key Laboratory for Tumor Immunology and Traditional Chinese Medicine Immunology, Institute of Basic Medicine, Shandong Academy of Medical Sciences, Jinan (China)

2015-12-01

Purpose: Inefficient T-cell reconstitution from x-ray–induced immune damage reduces antitumor response. To understand the profile of T-cell reconstitution after irradiation will overcome the barrier of antitumor immunity. This study aimed to identify the recovery profile of T-cell subsets following x-ray irradiation and to highlight the role of cinnamon on efficient T-cell restoration postexposure in the antitumor response. Methods and Materials: CD3{sup +}, CD8{sup +}, and CD4{sup +} T cells and Th1, Th2, Th17, and regulatory T (Treg) cells were evaluated at different time points after single low-dose total body irradiation (SLTBI) with or without cinnamon treatments. T-bet, GATA3, RORγt, and Foxp3 signaling specific for Th1, Th2, Th17, and Treg were also analyzed by RT-PCR assay. The effects of cinnamon on efficient T-cell subset reconstitution was confirmed in a lung melanoma model in irradiated mice. Results: Reconstitution of CD4{sup +} T cells was delayed more than that of CD8{sup +} T cells in T-cell restoration after SLTBI. The production of IFNγ by Th1 or Tc1 cells was sharply decreased and was accompanied by reduced T-bet mRNA, even when total T-cell numbers had recovered; the frequencies of Th17 and Treg cells and their specific transcription factors (RORγt and Foxp3, respectively) were obviously increased. Irradiation-induced inefficient T-cell reconstitution impaired the antitumor capacities in the lung melanoma model. Pretreatment with cinnamon in irradiated mice accelerated the generation of Th1 and reduced the differentiation of Treg cells by activating T-bet and limiting transcriptions of Foxp3. Improvement resulting from cinnamon pretreatment on the efficient T-cell recovery profile from SLTBI promoted antitumor immunity in the lung melanoma model. Conclusions: T-cell reconstitution from SLTBI was characterized by impaired Th1 and elevated Th17 and Treg cells. Cinnamon effectively improved the imbalance of T-cell subsets by promoting the

Hypo glycemic and Hypolipidaemic Effect of cinnamon Extract in Diabetic and irradiated Rats

International Nuclear Information System (INIS)

Mohamed, E.T.

2013-01-01

This study was made to investigate the antidiabetic and hypolipidemic potential of cinnamon against radiation and/or streptozotocin (STZ) induced diabetes in rats. In the experiment, a total of 36 rats were used and the rats were divided into six groups each of six rats: group 1, normal untreated rats; group 2, animals received only cinnamon (200 mg/kg/day) for 30 consecutive days; group 3, animals exposed to 4 Gy whole body gamma radiation as a single shot dose; group 4, animals were injected intraperitoneally with a freshly prepared solution of streptozotocin (45 mg/kg) in 0.1 M citrate buffer, ph 4.5; group 5, rats were injected intraperitoneally with a freshly prepared solution of streptozotocin (45 mg/kg), followed by irradiation at a dose level of 4 Gy; and group 6, rats were given orally cinnamon (200 mg/kg/day) for 30 days then injected intraperitoneally with a freshly prepared solution of streptozotocin followed by irradiation at a dose level of 4 Gy. Blood samples were collected from all groups for the determination of serum fasting blood sugar (FBG), glycidate hemoglobin (HbA1c), plasma insulin, serum C-peptide, serum total cholesterol (TC), Serum triglyceride (TG), high density lipoprotein-cholesterol (HDL-C) and low density lipoprotein-cholesterol (LDL-C). In diabetic and irradiated groups there was a highly significant increase in the percentage of (HbA1c) and concentration of FBG, TC, TG, LDL-C and a significant decrease in the level of HDL-C, plasma insulin and C-peptide compared to those of control group. Treatment of the diabetic irradiated rats with cinnamon caused a significant decrease in the percentage of HbA1c and concentration of FBG, TC, TG, LDL-C and significant increase in the level of HDL-C, plasma insulin and C-peptide compared to the diabetic irradiated rats. On the basis of these results, one could conclude that cinnamon exhibit hypo glycemic and hypolipidaemic properties and could be considered a promising agent for diabetes

Review article: cinnamon- and benzoate-free diet as a primary treatment for orofacial granulomatosis.

Science.gov (United States)

Campbell, H E; Escudier, M P; Patel, P; Challacombe, S J; Sanderson, J D; Lomer, M C E

2011-10-01

Orofacial granulomatosis is a rare chronic granulomatous inflammatory disease of the lips, face and mouth. The aetiology remains unclear but may involve an allergic component. Improvements have been reported with cinnamon- and benzoate-free diets. To explore the prevalence of compound and food sensitivity and examine the dietary treatments used in orofacial granulomatosis. A comprehensive literature search was carried out and relevant studies from January 1933 to January 2010 were identified using the electronic database search engines; AGRIS 1991-2008, AMED 1985-2008, British Nursing and Index archive 1985-2008, EMBASE 1980-2008, evidence based medicine review databases (e.g. Cochrane DSR), International Pharmaceutical and Medline 1950-2008. Common sensitivities identified, predominantly through patch testing, were to benzoic acid (36%) food additives (33%), perfumes and flavourings (28%), cinnamaldehyde (27%), cinnamon (17%), benzoates (17%) and chocolate (11%). The cinnamon- and benzoate-free diet has been shown to provide benefit in 54-78% of patients with 23% requiring no adjunctive therapies. A negative or positive patch test result to cinnamaldehyde, and benzoates did not predict dietary outcome. The most concentrated source of benzoate exposure is from food preservatives. Use of liquid enteral formulas can offer a further dietary therapy, particularly in children with orofacial granulomatosis. Management of orofacial granulomatosis is challenging but cinnamon- and benzoate-free diets appear to have a definite role to play. © 2011 Blackwell Publishing Ltd.

Fullerene-based materials for solar cell applications: design of novel acceptors for efficient polymer solar cells--a DFT study.

Science.gov (United States)

Mohajeri, Afshan; Omidvar, Akbar

2015-09-14

Fossil fuel alternatives, such as solar energy, are moving to the forefront in a variety of research fields. Polymer solar cells (PSCs) hold promise for their potential to be used as low-cost and efficient solar energy converters. PSCs have been commonly made from bicontinuous polymer:fullerene composites or so-called bulk heterojunctions. The conjugated polymer donors and the fullerene derivative acceptors are the key materials for high performance PSCs. In the present study, we have performed density functional theory calculations to investigate the electronic structures and magnetic properties of several representative C60 fullerene derivatives, seeking ways to improve their efficiency as acceptors of photovoltaic devices. In our survey, we have successfully correlated the LUMO energy level as well as chemical hardness, hyper-hardness, nucleus-independent chemical shift, and static dipole polarizability of PC60BM-like fullerene derivative acceptors with the experimental open circuit voltage of the photovoltaic device based on the P3HT:fullerene blend. The obtained structure-property correlations allow finding the best fullerene acceptor match for the P3HT donor. For this purpose, four new fullerene derivatives are proposed and the output parameters for the corresponding P3HT-based devices are predicted. It is found that the proposed fullerene derivatives exhibit better photovoltaic properties than the traditional PC60BM acceptor. The present study opens the way for manipulating fullerene derivatives and developing promising acceptors for solar cell applications.

An Efficient, “Burn in” Free Organic Solar Cell Employing a Nonfullerene Electron Acceptor

KAUST Repository

Cha, Hyojung; Wu, Jiaying; Wadsworth, Andrew; Nagitta, Jade; Limbu, Saurav; Pont, Sebastian; Li, Zhe; Searle, Justin; Wyatt, Mark F.; Baran, Derya; Kim, Ji-Seon; McCulloch, Iain; Durrant, James R.

2017-01-01

polymer blended with either the nonfullerene acceptor EH-IDTBR or the fullerene derivative, [6,6]-phenyl C71 butyric acid methyl ester (PC71 BM) as electron acceptors is reported. Inverted PffBT4T-2OD:EH-IDTBR blend solar cell fabricated without any

Low Band Gap Donor–Acceptor Type Polymers Containing 2,3-Bis(4-(decyloxyphenylpyrido[4,3-b]pyrazine as Acceptor and Different Thiophene Derivatives as Donors

Directory of Open Access Journals (Sweden)

Yan Zhang

2016-10-01

Full Text Available Four donor–acceptor type conducting polymers, namely poly(2,3-bis(4-decyloxyphenyl-5,8-bis(4-thiophen-2-ylpyrido[4,3-b]pyrazine (P1, poly(2,3-bis(4-decyloxyphenyl-5,8-bis(4-butylthiophen-2-ylpyrido[4,3-b]pyrazine (P2, poly(2,3-bis(4-(decyloxyphenyl-5,8-bis(4-hexyloxythiophen-2-ylpyrido[4,3-b]pyrazine (P3 and poly(2,3-bis(4-(decyloxyphenyl-5,8-bis(2,3-dihydrothieno[3,4-b][1,4]dioxin-7-ylpyrido[4,3-b]pyrazine (P4, containing thiophene or its derivative as the donor and pyrido[4,3-b]pyrazine as the acceptor were prepared and characterized by cyclic voltammetry, scanning electron microscopy, and UV-Vis spectroscopy to detect the influence of the donor units’ strength on the electrochromic performances. The results demonstrated that all of the polymers could be reversibly reduced and oxidized by p-type doping and n-type doping, and showed near-infrared activities and different color changes in p-type doping process. Especially, P3 and P4 showed lower optical band gap than P1 and P2 due to the strong electron-donating hexyloxythiophen group of P3 and ethylenedioxythiophene group of P4. Besides, P3 and P4 displayed the saturated green color at the neutral state and the desirable transparency at the oxidized state. All the polymers displayed desirable optical contrasts, satisfactory coloration efficiency, excellent stability and short switching time, which made the polymers fascinating candidates in the electrochromic device applications.

The effect of cinnamon bark (Cinnamomum burmanii) essential oil microcapsules on vacuumed ground beef quality

Science.gov (United States)

Brilliana, I. N.; Manuhara, G. J.; Utami, R.; Khasanah, L. U.

2017-04-01

Ground beef has a short shelf life because it is susceptible to damage due to microbial contamination and lipid oxidation. So some sort of preservation method such as refrigerated storage, vacuum packaging or natural preservative addition is needed to extend the shelf life of ground beef. A natural preservative that can be used as a food preservative is the cinnamon bark (Cinnamomum burmanii) essential oil microcapsules. The aim of the research was to determine the influence of a cinnamon bark essential oil microcapsules (0%;0.5% and 1% w/w of the ground beef) on the Total Plate Count (TPC), Thiobarbituric Acid (TBA), pH and color of ground beef during refrigerated storage (4±1°C). The result showed that cinnamon bark essential oil microcapsules affected the TPC, TBA, pH and color of ground beef. The addition of the cinnamon bark essential oil microcapsules on ground beef can inhibit microbial growth, inhibit lipid oxidation, inhibit discoloration and lowering pH of fresh ground beef during refrigerated storage compared to the control sample. The higher of the microcapsules were added, the higher the inhibition of microbial growth, lipid oxidation and discoloration of ground beef, indicating better preservation effects.

Phenyl vs Alkyl Polythiophene: A Solar Cell Comparison Using a Vinazene Derivative as Acceptor

KAUST Repository

Woo, Claire H.; Holcombe, Thomas W.; Unruh, David A.; Sellinger, Alan; Fréchet, Jean M. J.

2010-01-01

The solar cell performance of poly[3-(4-n-octyl)-phenylthiophene] (POPT) and poly(3hexylthiophene) (P3HT) are compared in devices using 4,7-bis(2-(l-(2-ethylhexyl)-4,5-dicyanoimidazol-2-yl)vinyi)benzo[c][l,2,5] -thiadiazole (EV-BT) as the electron acceptor. Despite their reduced light absorption, POPT:EV-BT devices generate higher photocurrents in both bilayer and bulk heterojunction (BHJ) architectures than analogous P3HT:EV-BT devices. Optimized POPT:EV-BT BHJ devices achieve 1.4% average efficiency, whereas the analogous P3HT devices only reach 1.1%. Morphology does not account for the large difference in performance as AFM studies of the active layer suggest, comparable levels of phase separation in the two systems. Reverse bias analysis demonstrates that P3HT devices have a higher maximum potential than POPT devices, but P3HT devices appear to be more severely limited by recombination losses under standard operating conditions. A possible explanation for the superior performance in POPT devices is that the pendant phenyl ring in POPT can twist out-of-plane and increase the separation distance with the acceptor molecule. A larger donor/acceptor separation distance can destabilize the geminate pair and lead to more efficient charge separation in POPT:EV-BT devices. Our results emphasize the importance of donor/acceptor pair interactions and its effect on charge separation, processes in polymer solar cells. © 2010 American Chemical Society.

Phenyl vs Alkyl Polythiophene: A Solar Cell Comparison Using a Vinazene Derivative as Acceptor

KAUST Repository

Woo, Claire H.

2010-03-09

The solar cell performance of poly[3-(4-n-octyl)-phenylthiophene] (POPT) and poly(3hexylthiophene) (P3HT) are compared in devices using 4,7-bis(2-(l-(2-ethylhexyl)-4,5-dicyanoimidazol-2-yl)vinyi)benzo[c][l,2,5] -thiadiazole (EV-BT) as the electron acceptor. Despite their reduced light absorption, POPT:EV-BT devices generate higher photocurrents in both bilayer and bulk heterojunction (BHJ) architectures than analogous P3HT:EV-BT devices. Optimized POPT:EV-BT BHJ devices achieve 1.4% average efficiency, whereas the analogous P3HT devices only reach 1.1%. Morphology does not account for the large difference in performance as AFM studies of the active layer suggest, comparable levels of phase separation in the two systems. Reverse bias analysis demonstrates that P3HT devices have a higher maximum potential than POPT devices, but P3HT devices appear to be more severely limited by recombination losses under standard operating conditions. A possible explanation for the superior performance in POPT devices is that the pendant phenyl ring in POPT can twist out-of-plane and increase the separation distance with the acceptor molecule. A larger donor/acceptor separation distance can destabilize the geminate pair and lead to more efficient charge separation in POPT:EV-BT devices. Our results emphasize the importance of donor/acceptor pair interactions and its effect on charge separation, processes in polymer solar cells. © 2010 American Chemical Society.

Evaluation of active ingredients and larvicidal activity of clove and cinnamon essential oils against Anopheles gambiae (sensu lato).

Science.gov (United States)

Thomas, Adelina; Mazigo, Humphrey D; Manjurano, Alphaxard; Morona, Domenica; Kweka, Eliningaya J

2017-09-06

Mosquitoes are well-known vectors of many diseases including malaria and lymphatic filariasis. Uses of synthetic insecticides are associated with high toxicity, resistance, environmental pollution and limited alternative, effective synthetic insecticides. This study was undertaken to evaluate the larvicidal efficacy of clove and cinnamon essential oils against laboratory Anopheles gambiae (sensu stricto) and wild An. arabiensis larvae. The standard WHO guideline for larvicides evaluation was used, and the GC-MS machine was used for active compounds percentage composition analysis and structures identification. Probit regression analysis was used for LC 50 and LC 95 calculations while a t-test was used to test for significant differences between laboratory-reared and wild larvae populations in each concentration of plant extract. Mortality effect of clove and cinnamon essential oils against wild and laboratory-reared larvae had variations indicated by their LC 50 and LC 95 values. The mortality at different concentrations of cinnamon and clove post-exposure for wild and laboratory-reared larvae were dosage-dependent and were higher for cinnamon than for clove essential oils. The mortality effect following exposure to a blend of the two essential oils was higher for blends containing a greater proportion of cinnamon oil. In the chemical analysis of the active ingredients of cinnamon essential oil, the main chemical content was Eugenol, and the rarest was β-Linalool while for clove essential oil, the main chemical content was Eugenol and the rarest was Bicyclo. The essential oils showed a larvicidal effect which was concentration-dependent for both laboratory and wild collected larvae. The active ingredient compositions triggered different responses in mortality. Further research in small-scale should be conducted with concentrated extracted compounds.

Effect of cinnamon (Cinnamomum verum) bark essential oil on the halitosis-associated bacterium Solobacterium moorei and in vitro cytotoxicity.

Science.gov (United States)

LeBel, Geneviève; Haas, Bruno; Adam, Andrée-Ann; Veilleux, Marie-Pier; Lagha, Amel Ben; Grenier, Daniel

2017-11-01

Halitosis, also known as bad breath or oral malodour, is a condition affecting a large proportion of the population. Solobacterium moorei is a Gram-positive anaerobic bacterium that has been specifically associated with halitosis. In this study, we investigated the effects of essential oils, more particularly cinnamon bark oil, on growth, biofilm formation, eradication and killing, as well as hydrogen sulfide (H 2 S) production by S. moorei. A broth microdilution assay was used to determine the antibacterial activity of essential oils. Biofilm formation was assessed by a crystal violet staining assay and scanning electron microscopy. The biofilm of S. moorei was characterized by enzymatic treatments. Biofilm killing was determined by a luminescence assay monitoring ATP production. H 2 S production was quantified with a colorimetric assay. The biocompatibility of cinnamon oil was investigated using a gingival keratinocyte cell line. Among the ten essential oils tested, cinnamon oil was found to be the most powerful against S. moorei with MIC and MBC values of 0.039% and 0.156%, respectively. The biofilm formed by S. moorei was then characterized. The fact that DNase I and to a lesser extent proteinase K significantly reduced biofilm formation by S. moorei and induced its eradication suggests that the extracellular matrix of S. moorei biofilm may be mainly containing a DNA backbone associated with proteins. At concentrations below the MIC, cinnamon oil reduced S. moorei biofilm formation that resulted from an attenuation of bacterial growth. It was also found that treatment of a pre-formed biofilm of S. moorei with cinnamon oil significantly decreased its viability although it did not cause its eradication. Cinnamon oil had an inhibitory effect on the production of H 2 S by S. moorei. Lastly, it was found that at concentrations effective against S. moorei, no significant loss of viability in gingival keratinocytes occurred after a 1-h exposure. Our study brought

Intramolecular Charge-Transfer Interaction of Donor-Acceptor-Donor Arrays Based on Anthracene Bisimide.

Science.gov (United States)

Iwanaga, Tetsuo; Ogawa, Marina; Yamauchi, Tomokazu; Toyota, Shinji

2016-05-20

We designed anthracene bisimide (ABI) derivatives having two triphenylamine (TPA) groups as donor units at the 9,10-positions to form a novel π-conjugated donor-acceptor system. These compounds and their analogues with ethynylene linkers were synthesized by Suzuki-Miyaura and Sonogashira coupling reactions, respectively. In UV-vis spectra, the linker-free derivatives showed broad absorption bands arising from intramolecular charge-transfer interactions. Introducing ethynylene linkers resulted in a considerable red shift of the absorption bands. In fluorescence spectra, the ethynylene derivatives showed intense emission bands at 600-650 nm. Their photophysical and electrochemical properties were compared with those of the corresponding mono TPA derivatives on the basis of theoretical calculations and cyclic voltammetry to evaluate the intramolecular electronic interactions between the donor and acceptor units.

An overview of molecular acceptors for organic solar cells

Directory of Open Access Journals (Sweden)

Hudhomme Piétrick

2013-07-01

Full Text Available Organic solar cells (OSCs have gained serious attention during the last decade and are now considered as one of the future photovoltaic technologies for low-cost power production. The first dream of attaining 10% of power coefficient efficiency has now become a reality thanks to the development of new materials and an impressive work achieved to understand, control and optimize structure and morphology of the device. But most of the effort devoted to the development of new materials concerned the optimization of the donor material, with less attention for acceptors which to date remain dominated by fullerenes and their derivatives. This short review presents the progress in the use of non-fullerene small molecules and fullerene-based acceptors with the aim of evaluating the challenge for the next generation of acceptors in organic photovoltaics.

Ultrastructural evaluation of the effects of cinnamon on the nervus ischiadicus in diabetic rats

International Nuclear Information System (INIS)

Bahceci, Selen; Akkus, Murat; Aluclu, Mehmet U; Canoruc, Naime; Bahceci, Mithat; Gokalp, Deniz; Baran, Sedat; Akbalik, Mehmet E

2009-01-01

To investigate the effects of oral cinnamon supplementation on the nervus ischiadicus at the electron microscopical level in rats. This study was performed between 2004-2006 in Dicle University School of Medicine, Diyarbakir, Turkey in 15 adult Sprague-Dawley rats. Rats were divided into 3 groups; control (C) (n=5), diabetic without cinnamon (D) (n=5), and diabetic with cinnamon (D-C) (n=5). Diabetes was induced with intraperitoneal alloxan administration. All diabetic rats were treated with human insulin. All rats were fed with standard pellet chow. The D-C group rats were fed with standard pellet chow plus Cinnamomum cassia at the dose of 400mg/kg. All rats were sacrificed after 3 months and we obtained the nervus ischiadicus of all rats. Contrast stained thin sections evaluated by Jeol-TEM-1010 electron microscope, were not statistically different in both groups and photo samples were obtained. Mean blood glucose, hemoglobin A1C, and lipid profile were not statistically different in both groups. Marked detachment of myelin lamellae at Schmidt-Lanterman clefts, lysis in cristae mitochondrialis and degenerative changes, severe dispersion of organelles in neurolemma, mesoaxon region, and remarkable edema at the endoneurium were found in diabetic rats. On the contrary, mesoaxon, nucleus, nucleolus and myelin sheet were almost of normal appearance at the ultra-structural level in the D-C group. Cinnamon extracts may have beneficial effects on the development of diabetic neuropathy in alloxan induced diabetic rats. (author)

Michael Scott

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Ersin Hussein

2015-04-01

While Michael has contributed significantly to the field of classics and ancient history by publishing extensively, he has also enjoyed great success in engaging wider audiences with the ancient world. He regularly talks in schools around the country, writes books intended for the popular market as well as articles for national and international newspapers and magazines. Michael's experience in writing and presenting a range of programmes intended for TV and radio audiences has made him a household name. He has written and presented programmes for the National Geographic, History Channel, Nova, and the BBC including Delphi: bellybutton of the ancient world (BBC4; Guilty Pleasures: luxury in the ancient and medieval words (BBC4; Jesus: rise to power (Natural Geographic; Ancient Discoveries (History Channel; Who were the Greeks? (BBC2; The Mystery of the X Tombs (BBC2/Nova; The Greatest Show on Earth (BBC4, in conjunction with the Open University. He has also presented a radio series for BBC Radio 4, Spin the Globe. Michael's most recent programme, Roman Britain from the Air, was aired on ITV in December 2014. In this interview, I talk to him about his engagement with other disciplines within the humanities, his forthcoming book project, and his experiences writing and presenting TV and radio documentaries.

Evaluation of anti-diabetic effects of hydroalcoholic extract of green tea and cinnamon on streptozotocin-induced diabetic rats

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Ghasem Shokri

2015-06-01

Full Text Available Today diabetes is one of the most common diseases in the world that affects half of the world population. The use of medicinal herbs especially green tea and cinnamon has been taken into consideration for relieving the symptoms of diabetes, but there were some different ideas about their effectiveness. So, this study was conducted to evaluate the effect of cinnamon and green tea extract, individually and in combination, on blood glucose and weight loss in diabetic mice with Streptozotocin (STZ. The experiment was performed on 50 Wistar rats.  A total of 50 rats were divided into 10 groups of 5 and STZ was injected at the dose of 40 mg/kg/day for 5 days intraperitoneally. After diabetes induction, three groups received, 50, 100 and 200 mg doses of green tea extract,  three groups received 50, 100 and 200 mg doses of cinnamon extract  and three final groups received 50, 100 and 200 mg doses of  cinnamon  and green tea in combination by gavages daily for 6 weeks. After each period of treatments, blood glucose and the weight of animals were determined. At the end of the sixth week, blood glucose and weight loss were improved in diabetic rats in a dose-dependent manner and the dose of 200 mg/kg extract cinnamon with green tea had the most appropriate synergic effect.

Gum acacia coating with garlic and cinnamon as an alternate ...

African Journals Online (AJOL)

Madhumita

The antibacterial activity of gum arabic coating with ... Key words: Gum acacia coating, garlic, cinnamon, antioxidant, antimicrobial, meat, ... cinnamaldehyde and eugenol inhibit production of an ... antioxidant activity because these two properties are ... temperatures .... activity of these spices but no report on its application.

Antioxidant and antimicrobial properties of ethanolic extracts of guarana, boldo, rosemary and cinnamon

Directory of Open Access Journals (Sweden)

Jeannine Bonilla

2017-06-01

Full Text Available Abstract In this investigation, the ethanolic extracts of two less known plants, little reported in the literature (guarana and boldo leaves were studied in comparison with the ethanolic extracts of two well studied plants (cinnamon and rosemary, regarding their colour, GC-MS profile, phenolic content and their antioxidant and antimicrobial properties. The rosemary (59.20 ± 0.28 and guarana (56.63 ± 0.54 extracts showed the highest values for luminosity (L* and the UV-Vis absorption increased when L* decreased. GC-MS identified a limited number of compounds in the cinnamon and guarana extracts. The cinnamon extract showed the highest value for the total phenolic content (172 mg GA/g extract as compared to the other extracts. The highest antioxidant capacity was observed for the boldo leaves extract in the TEAC (6.66 ± 0.17 mM assay and for the rosemary extract in the DPPH (0.80 ± 0.14 mg/L test. In addition, all the extracts showed antimicrobial activity against the S. aureus strain, indicating that all the extracts studied could be used by food industries to develop new active food packaging materials.

Antibacterial activity of cinnamon ethanol extract (cinnamomum burmannii) and its application as a mouthwash to inhibit streptococcus growth

Science.gov (United States)

Waty, Syahdiana; Suryanto, Dwi; Yurnaliza

2018-03-01

Cinnamon bark has been commonly used as spicy and traditional medicine. It contains several antibacterial compounds such as flavonoids, saponins, and cinnamaldehyde. Several studies have been done to know the antibacterial effect on bacteria such as Streptococcus in vitro. This study aimed to examine the antibacterial activity of cinnamon ethanol extract against Streptococcus and its application as mouthwash to inhibit the bacteria. The cinnamon bark was macerated followed by extracted in 80% ethanol. Bacterial samples were isolated from dental plaque of patients visiting dental clinic drg. Syahdiana Waty in Medan, North Sumatra. The isolates were identified using Vitek 2 compact. Secondary metabolites were detected using previously described method. Antibacterial assay was done at extract concentration of 6.25%, 12.5%, and 25%. The result showed that alkaloids, flavonoids, saponins, and glycoside were detected in the extract. Nine bacterial species were identified as Streptococcus mitis, S. sanguinis, S. salivarius, S. pluranimalium, S. pneumoniae, S. alactolyticus, Kocuria rosea, Kocuria kristinae, and Spingomonas paucimolis. It showed that the extract of Cinnamon bark significantly inhibited Streptococcus growth, and it was effective as mouthwash.

Inhibitory effects of cinnamon and clove essential oils on mold growth on baked foods.

Science.gov (United States)

Ju, Jian; Xu, Xiaomiao; Xie, Yunfei; Guo, Yahui; Cheng, Yuliang; Qian, He; Yao, Weirong

2018-02-01

This study evaluated the minimum inhibition concentration (MIC) and minimum lethal concentration (MLC) of cinnamon and clove essential oils against mold growth on green bean cake and finger citron crisp cake, and also examined the effects of these two essential oils and their application methods on the shelf life of the baked products in normal and vacuum packages by accelerated storage test. The results showed that the MIC of cinnamon and clove essential oils against molds were 0.21-0.83 and 0.21-1.67μL/mL, respectively and the MLC were 0.42-0.83 and 0.83-1.67μL/mL, respectively. In normal package cinnamon and clove essential oils could prolong the shelf life of green bean cake 9-10 and 3-4days, respectively and could prolong the shelf life of finger citron crisp cake 5-6 and 2-3days, respectively. And in vacuum package they were 15-16, 8-9, 10-12 and 7-9days, respectively in turn. Copyright © 2017. Published by Elsevier Ltd.

Photoluminescence quenching through resonant energy transfer in blends of conjugated polymer with low-molecular acceptor

International Nuclear Information System (INIS)

Zapunidi, S. A.; Paraschuk, D. Yu.

2008-01-01

A model is proposed for photoluminescence quenching due to resonant energy transfer in a blend of a conjugated polymer and a low-molecular energy acceptor. An analytical dependence of the normalized photoluminescence intensity on the acceptor concentration is derived for the case of a homogeneous blend. This dependence can be described by two fitting parameters related to the Foerster radii for energy transfer between conjugated segments of the polymer and between the conjugated polymer segment and the energy acceptor. Asymptotic approximations are obtained for the model dependence that make it possible to estimate the contribution from the spatial migration of excitons to the photoluminescence quenching. The proposed model is used to analyze experimental data on the photoluminescence quenching in a blend of the soluble derivative of poly(p-phenylene vinylene) and trinitrofluorenone [13]. The Foerster radius for resonant energy transfer between the characteristic conjugated segment of poly(p-phenylene vinylene) and the energy acceptor is determined to be r F = 2.6 ± 0.3 nm

Michael Levitt and Computational Biology

Science.gov (United States)

dropdown arrow Site Map A-Z Index Menu Synopsis Michael Levitt and Computational Biology Resources with Michael Levitt, PhD, professor of structural biology at the Stanford University School of Medicine, has function. ... Levitt's early work pioneered computational structural biology, which helped to predict

Comparative effect of ethylene oxide and gamma irradiation on the chemical sensory and microbial quality of ginger, cinnamon, fennel and fenugreek

International Nuclear Information System (INIS)

Toofanian, F.; Stegeman

1986-01-01

The effect of gamma irradiation and ethylene oxide fumigation on the microbiological and sensory properties of ground cinnamon, ginger, fennel and fenugreek, and on the volatile oil content of ground cinnamon, ginger and fennel was investigated. Ground ginger, cinnamon, fennel and fenugreek were obtained from a Dutch trade company. Ginger originated from China, cinnamon was produced in Indonesia and fennel and fenugreek were produced in India. The samples were ground by the trade companies and divided in three parts. One part was fumigated by the trade companies at ambient temperatures during eight hours with ethylene oxide (EO) at a concentration of 1500/m 3 . The second part was gamma irradiated at room temperature in aluminium/polyethylene bags at the 40 KCi cobalt-60 research source of the pilot plant for food irradiation in Wageningen. The untreated, fumigated and irradiated samples were stored in gas-impermeable packages. It was found that for cinnamon and ginger a 6 KGy dose, for fennel, 6-10 KGy and for fenugreek 6-8 KGy dose were equal in microbial effects to the commercial established fumigation process. No significant change in the volatile oil content of the fumigated or irradiated cinnamon and fennel has been observed. Irradiation of ginger with a dose of 5 KGy resulted in a slight decrease of 14% while fumigated ginger showed no significant loss in volatile oil content. Between the untreated irradiated or fumigated spices no major differences in sensory properties were found

Repeated systemic administration of the cinnamon essential oil possesses anti-anxiety and anti-depressant activities in mice.

Science.gov (United States)

Sohrabi, Reyhaneh; Pazgoohan, Nasim; Seresht, Hasan Rezaei; Amin, Bahareh

2017-06-01

The present study aimed to evaluate the putative antidepressant and anti-anxiety effects of the cinnamon essential oil when administered acute (for 3 doses) and sub-acute (for 14 days) to mice. In an acute experimental study, forced swim test (FST) was conducted to evaluate the antidepressant-like behavior of animals treated with the intraperitoneal (IP) essential oil of cinnamon in triple doses (0.5, 1, and 2 mg/kg). In a sub-acute study (14 days in 24-hr intervals) antidepressant-like effects of essential oil (0.5, 1, and 2 mg/kg) with the same route were assessed in FST and tail suspension test (TST). Anti-anxiety and motor activities were evaluated using elevated plus-maze (EPM) and open field tests, respectively. Determination of different constituents within the sample oil was via gas chromatography-mass spectrometry (GC-MS) analysis. Repetitive administration of cinnamon essential oil (0.5, 1, 2 mg/kg) during 14 days significantly decreased the time of immobility in both FST and TST as compared to the control group. Mice treated with oil at the dose of 2 mg/kg spent a longer time and had more entries into the open arms of EPM as compared with the vehicle-treated ones. According to GC-MS analysis, 46 chemical compounds were identified in the studied cinnamon essential oil with the main constituent being trans-cinnamaldehyde (87.32%). Cinnamon essential oil might be used as an adjunctive therapy in improving symptoms of depressive and anxiety disorders. However, dose-response effects need further evaluation. Trans-cinnamaldehyde might be responsible for the beneficial effect observed.

The effects of cinnamon on glycemic indexes and insulin resistance in adult male diabetic rats with streptozotocin

Directory of Open Access Journals (Sweden)

SEbrahim Hosseini

2015-02-01

Full Text Available Background: Diabetes is a common disease that for its treatment and control different methods are recommended such as the use of natural remedies and lifestyle modification. Since the use of herbal medicines have less side effects than many chemical drugs, hence, this study aimed to investigate the effect of cinnamon extract on blood glucose, insulin and insulin resistance in diabetic rats with streptozotocin. Materials and Methods: This experimental study was conducted on 40 adult male rats, that were randomly divided into 4 groups including non diabetic control, diabetic control and two experimental groups receiving doses 60mg/kg of cinnamon extract for 3 and 6 weeks. At the end, by phlebotomizing of rats' heart, blood glucose and insulin were measured and using HOMA score insulin resistance was measured. To be normal data distribution, Kolmogorov-Smirnov test was done and data analyzed by SPSS-20 software and ANOVA and post hoc Tukey tests. Results: The results showed that in the group receiving the cinnamon extract, glycemic and insulin indexes were significantly adjusted. Conclusion: Cinnamon is probably due to have flavonoid and antioxidant compounds with antioxidant by increasing glucose uptake via the different body cells and due to reduction of oxidative stress level led to adjust glycemic and insulin indexes of blood

Study of the Contributions of Donor and Acceptor Photoexcitations to Open Circuit Voltage in Bulk Heterojunction Organic Solar Cells

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Douglas Yeboah

2017-10-01

Full Text Available One of the key parameters in determining the power conversion efficiency (PCE of bulk heterojunction (BHJ organic solar cells (OSCs is the open circuit voltage . The processes of exciting the donor and acceptor materials individually in a BHJ OSC are investigated and are found to produce two different expressions for . Using the contributions of electron and hole quasi-Fermi levels and charge carrier concentrations, the two different expressions are derived as functions of the energetics of the donor and acceptor materials and the photo-generated charge carrier concentrations, and calculated for a set of donor-acceptor blends. The simultaneous excitation of both the donor and acceptor materials is also considered and the corresponding , which is different from the above two, is derived. The calculated from the photoexcitation of the donor is found to be somewhat comparable with that obtained from the photoexcitation of the acceptor in most combinations of the donor and acceptor materials considered here. It is also found that the calculated from the simultaneous excitations of donor and acceptor in BHJ OSCs is also comparable with the other two . All three thus derived produce similar results and agree reasonably well with the measured values. All three depend linearly on the concentration of the photoexcited charge carriers and hence incident light intensity, which agrees with experimental results. The outcomes of this study are expected to help in finding materials that may produce higher and hence enhanced PCE in BHJ OSCs.

Gum acacia coating with garlic and cinnamon as an alternate ...

African Journals Online (AJOL)

Meat and fish, the most perishable foods need to be preserved preferably with natural preservatives. In our study, we have proven that spices like garlic and cinnamon that are used as regular ingredients in cooking can act as preservative due to their rich antibacterial and antioxidant profile. The minimum inhibitory ...

Electron Acceptors Based on α-Substituted Perylene Diimide (PDI) for Organic Solar Cells

Energy Technology Data Exchange (ETDEWEB)

Zhao, Donglin [Department; Wu, Qinghe [Department; Cai, Zhengxu [Department; Zheng, Tianyue [Department; Chen, Wei [Materials; Institute; Lu, Jessica [Department; Yu, Luping [Department

2016-02-02

Perylene diimide (PDI) derivatives functionalized at the ortho-position (αPPID, αPBDT) were synthesized and used as electron acceptors in non-fullerene organic photovoltaic cells. Because of the good planarity and strong π-stacking of ortho-functionalized PDI, the αPPID and αPBDT exhibit a strong tendency to form aggregates, which endow the materials with high electron mobility. The inverted OPVs employing αPDI-based compounds as the acceptors and PBT7-Th as the donor give the highest power conversion efficiency (PCE) values: 4.92% for αPBDT-based devices and 3.61% for αPPID-based devices, which are, respectively, 39% and 4% higher than that of their β-substituted counterparts βPBDT and βPPID. Charge separation studies show more efficient exciton dissociation at interfaces between αPDI-based compounds and PTB7-Th. The results suggest that α-substituted PDI derivatives are more promising electron acceptors for organic photovoltaic (OPV) components than β-isomers.

Jack Michael's Motivation

Science.gov (United States)

Miguel, Caio F.

2013-01-01

Among many of Jack Michael's contributions to the field of behavior analysis is his behavioral account of motivation. This paper focuses on the concept of "motivating operation" (MO) by outlining its development from Skinner's (1938) notion of "drive." Conceptually, Michael's term helped us change our focus on…

Cinnamon Use in Type 2 Diabetes: An Updated Systematic Review and Meta-Analysis

Science.gov (United States)

Allen, Robert W.; Schwartzman, Emmanuelle; Baker, William L.; Coleman, Craig I.; Phung, Olivia J.

2013-01-01

PURPOSE Cinnamon has been studied in randomized controlled trials (RCTs) for its glycemic-lowering effects, but studies have been small and show conflicting results. A prior meta-analysis did not show significant results, but several RCTs have been published since then. We conducted an updated systematic review and meta-analysis of RCTs evaluating cinnamon’s effect on glycemia and lipid levels. METHODS MEDLINE, Embase, and Cochrane Central Register of Controlled Trials (CENTRAL) were searched through February 2012. Included RCTs evaluated cinnamon compared with control in patients with type 2 diabetes and reported at least one of the following: glycated hemoglobin (A1c), fasting plasma glucose, total cholesterol, low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), or triglycerides. Weighted mean differences (with 95% confidence intervals) for endpoints were calculated using random-effects models. RESULTS In a meta-analysis of 10 RCTs (n = 543 patients), cinnamon doses of 120 mg/d to 6 g/d for 4 to 18 weeks reduced levels of fasting plasma glucose (−24.59 mg/dL; 95% CI, −40.52 to −8.67 mg/dL), total cholesterol (−15.60 mg/dL; 95% CI, −29.76 to −1.44 mg/dL), LDL-C (−9.42 mg/dL; 95% CI, −17.21 to −1.63 mg/dL), and triglycerides (−29.59 mg/dL; 95% CI, −48.27 to −10.91 mg/dL). Cinnamon also increased levels of HDL-C (1.66 mg/dL; 95% CI, 1.09 to 2.24 mg/dL). No significant effect on hemoglobin A1c levels (−0.16%; 95%, CI −0.39% to 0.02%) was seen. High degrees of heterogeneity were present for all analyses except HDL-C (I2 ranging from 66.5% to 94.72%). CONCLUSIONS The consumption of cinnamon is associated with a statistically significant decrease in levels of fasting plasma glucose, total cholesterol, LDL-C, and triglyceride levels, and an increase in HDL-C levels; however, no significant effect on hemoglobin A1c was found. The high degree of heterogeneity may limit the ability to apply these results

Impact of Nonfullerene Acceptor Core Structure on the Photophysics and Efficiency of Polymer Solar Cells

KAUST Repository

Alamoudi, Maha

2018-03-02

Small-molecule “nonfullerene” acceptors are promising alternatives to fullerene (PC61/71BM) derivatives often used in bulk heterojunction (BHJ) organic solar cells; yet, the efficiency-limiting processes and their dependence on the acceptor structure are not clearly understood. Here, we investigate the impact of the acceptor core structure (cyclopenta-[2,1-b:3,4-b′]dithiophene (CDT) versus indacenodithiophene (IDTT)) of malononitrile (BM)-terminated acceptors, namely CDTBM and IDTTBM, on the photophysical characteristics of BHJ solar cells. Using PCE10 as donor polymer, the IDTT-based acceptor achieves power conversion efficiencies (8.4%) that are higher than those of the CDT-based acceptor (5.6%) because of a concurrent increase in short-circuit current and open-circuit voltage. Using (ultra)fast transient spectroscopy we demonstrate that reduced geminate recombination in PCE10:IDTTBM blends is the reason for the difference in short-circuit currents. External quantum efficiency measurements indicate that the higher energy of interfacial charge-transfer states observed for the IDTT-based acceptor blends is the origin of the higher open-circuit voltage.

Impact of Nonfullerene Acceptor Core Structure on the Photophysics and Efficiency of Polymer Solar Cells

KAUST Repository

Alamoudi, Maha; Khan, Jafar Iqbal; Firdaus, Yuliar; Wang, Kai; Andrienko, Denis; Beaujuge, Pierre; Laquai, Fré dé ric

2018-01-01

Small-molecule “nonfullerene” acceptors are promising alternatives to fullerene (PC61/71BM) derivatives often used in bulk heterojunction (BHJ) organic solar cells; yet, the efficiency-limiting processes and their dependence on the acceptor structure are not clearly understood. Here, we investigate the impact of the acceptor core structure (cyclopenta-[2,1-b:3,4-b′]dithiophene (CDT) versus indacenodithiophene (IDTT)) of malononitrile (BM)-terminated acceptors, namely CDTBM and IDTTBM, on the photophysical characteristics of BHJ solar cells. Using PCE10 as donor polymer, the IDTT-based acceptor achieves power conversion efficiencies (8.4%) that are higher than those of the CDT-based acceptor (5.6%) because of a concurrent increase in short-circuit current and open-circuit voltage. Using (ultra)fast transient spectroscopy we demonstrate that reduced geminate recombination in PCE10:IDTTBM blends is the reason for the difference in short-circuit currents. External quantum efficiency measurements indicate that the higher energy of interfacial charge-transfer states observed for the IDTT-based acceptor blends is the origin of the higher open-circuit voltage.

Potent haloperidol derivatives covalently binding to the dopamine D2 receptor.

Science.gov (United States)

Schwalbe, Tobias; Kaindl, Jonas; Hübner, Harald; Gmeiner, Peter

2017-10-01

The dopamine D 2 receptor (D 2 R) is a common drug target for the treatment of a variety of neurological disorders including schizophrenia. Structure based design of subtype selective D 2 R antagonists requires high resolution crystal structures of the receptor and pharmacological tools promoting a better understanding of the protein-ligand interactions. Recently, we reported the development of a chemically activated dopamine derivative (FAUC150) designed to covalently bind the L94C mutant of the dopamine D 2 receptor. Using FAUC150 as a template, we elaborated the design and synthesis of irreversible analogs of the potent antipsychotic drug haloperidol forming covalent D 2 R-ligand complexes. The disulfide- and Michael acceptor-functionalized compounds showed significant receptor affinity and an irreversible binding profile in radioligand depletion experiments. Copyright © 2017 Elsevier Ltd. All rights reserved.

Associative Memory Acceptors.

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Card, Roger

The properties of an associative memory are examined in this paper from the viewpoint of automata theory. A device called an associative memory acceptor is studied under real-time operation. The family "L" of languages accepted by real-time associative memory acceptors is shown to properly contain the family of languages accepted by one-tape,…

Michael Niegl (1985-2009)

CERN Multimedia

2009-01-01

Our friend and colleague Michael Niegl died in a tragic accident in the first hours of the new year. Michael was a Master’s student in Microsystems Engineering at the University of Applied Sciences Wiener Neustadt. He was responsible for the development of the ATLAS Beam Conditions Monitor (BCM) ROD FPGA firmware, which acquires the data from the BCM detector modules and provides online monitoring of the LHC beams within the ATLAS experiment. He spent several months at CERN to carry out beam tests on the BCM detectors and received his Bachelor of Science with first class honours for his thesis: Concept and Implementation of an FPGA-based Data Recorder and Processor for the ATLAS Beam Conditions Monitor. Michael spent six months at CERN last year to finish the development and commissioning of the ROD firmware for the first beam. He worked the entire night of 10 September to fine tune the system for the first beam. It was a joy to ...

The Effect of Aqueous Extract of Cinnamon on the Metabolome of Plasmodium falciparum Using 1HNMR Spectroscopy

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Shirin Parvazi

2016-01-01

Full Text Available Malaria is responsible for estimated 584,000 deaths in 2013. Researchers are working on new drugs and medicinal herbs due to drug resistance that is a major problem facing them; the search is on for new medicinal herbs. Cinnamon is the bark of a tree with reported antiparasitic effects. Metabonomics is the simultaneous study of all the metabolites in biological fluids, cells, and tissues detected by high throughput technology. It was decided to determine the mechanism of the effect of aqueous extract of cinnamon on the metabolome of Plasmodium falciparum in vitro using 1HNMR spectroscopy. Prepared aqueous extract of cinnamon was added to a culture of Plasmodium falciparum 3D7 and its 50% inhibitory concentration determined, and, after collection, their metabolites were extracted and 1HNMR spectroscopy by NOESY method was done. The spectra were analyzed by chemometric methods. The differentiating metabolites were identified using Human Metabolome Database and the metabolic cycles identified by Metaboanalyst. 50% inhibitory concentration of cinnamon on Plasmodium falciparum was 1.25 mg/mL with p<0.001. The metabolites were identified as succinic acid, glutathione, L-aspartic acid, beta-alanine, and 2-methylbutyryl glycine. The main metabolic cycles detected were alanine and aspartame and glutamate pathway and pantothenate and coenzyme A biosynthesis and lysine biosynthesis and glutathione metabolism, which are all important as drug targets.

Insulin resistance improvement by cinnamon powder in polycystic ovary syndrome: A randomized double-blind placebo controlled clinical trial.

Science.gov (United States)

Hajimonfarednejad, Mahdie; Nimrouzi, Majid; Heydari, Mojtaba; Zarshenas, Mohammad Mehdi; Raee, Mohammad Javad; Jahromi, Bahia Namavar

2018-02-01

Our aim is to assess the effect of cinnamon powder capsules on insulin resistance, anthropometric measurements, glucose and lipid profiles, and androgens of women with polycystic ovarian syndrome (PCOS). Out of 80 women that were diagnosed as PCOS by Rotterdam Criteria, 66 were enrolled in this randomized double-blind placebo-controlled clinical trial. All of the PCOS women were taking medroxy progesterone acetate 10 mg/day for the last 10 days of their menstrual cycles. The cases were randomly allocated to 2 groups. The women in the first group were treated by cinnamon powder capsules 1.5 g/day in 3 divided doses for 12 weeks and the second group by similar placebo capsules. Anthropometric measurements, fasting blood sugar, fasting insulin, blood glucose 2 hr after taking 75 g oral glucose, HbA1c, testosterone, dehydroepiandrosterone sulphate, homeostatic model assessment for insulin resistance, triglyceride, and cholesterol (low-density lipoprotein, high-density lipoprotein, and total) before and after the intervention were evaluated and compared as outcome measures. Fasting insulin (p = .024) and homeostatic model assessment for insulin resistance (p = .014) were reduced after 12 weeks in the cinnamon group compared with the placebo. There was also a significant decrease in low-density lipoprotein in cinnamon group (p = .004) as compared with baseline that caused significant difference with placebo (p = .049). However, changes in other outcome measurements did not lead to statistically significant difference with placebo. The present results suggest that complementary supplementation of cinnamon significantly reduced fasting insulin and insulin resistance in women with PCOS. Copyright © 2017 John Wiley & Sons, Ltd.

Do Cinnamon Supplements Have a Role in Glycemic Control in Type 2 Diabetes – A Narrative Review?

OpenAIRE

Costello, Rebecca B.; Dwyer, Johanna T.; Saldanha, Leila; Bailey, Regan L.; Merkel, Joyce; Wambogo, Edwina

2016-01-01

Cinnamon (Cinnamomum sp.) has been suggested to help patients with type 2 diabetes mellitus (T2DM) achieve better glycemic control although conclusions from meta-analyses are mixed. To evaluate whether the use of cinnamon dietary supplements by adults with T2DM had clinically meaningful effects on glycemic control, as measured by changes in fasting plasma glucose (FPG) or hemoglobin A1c (HbA1c), a comprehensive PubMed literature search was performed. Eleven RCTs were identified meeting our in...

Effect of cinnamon on gastric emptying, arterial stiffness, postprandial lipemia, glycemia, and appetite responses to high-fat breakfast

OpenAIRE

Markey, Oonagh; McClean, Conor M; Medlow, Paul; Davison, Gareth W; Trinick, Tom R; Duly, Ellie; Shafat, Amir

2011-01-01

Abstract Background Cinnamon has been shown to delay gastric emptying of a high-carbohydrate meal and reduce postprandial glycemia in healthy adults. However, it is dietary fat which is implicated in the etiology and is associated with obesity, type 2 diabetes and cardiovascular disease. We aimed to determine the effect of 3 g cinnamon (Cinnamomum zeylanicum) on GE, postprandial lipemic and glycemic responses, oxidative stress, arterial stiffness, as well as appetite sensations and subsequent...

Comparative effect of ethylene oxide and gamma irradiation on the chemical, sensory and microbial quality of ginger, cinnamon, fennel and fenugreek

International Nuclear Information System (INIS)

Toofanian, F.; Stegeman, H.

1988-01-01

The effect of gamma irradiation and ethylene oxide fumigation on the microbiological and sensory properties and on the volatile oil content of ground cinnamon, ginger and fennel as well as on the sensory properties of fenugreek were investigated. It was found that for cinnamon and ginger a 6 kGy dose, for fennel 6-10 kGy and for fenugreek 6-8 kGy dose were equal in microbial effects to the commercially established fumigation process. No significant change in the volatile oil contents of the fumigated or irradiated cinnamon and fennel has been observed. Between the untreated, irradiated or fumigated spices no major differences in sensory properties were found. (author) 13 refs.; 1 fig.; 5 tabs

Michael J. Fox: Spurring Research on Parkinson's

Science.gov (United States)

... turn JavaScript on. Feature: Parkinson's Disease Michael J. Fox: Spurring Research on Parkinson's Past Issues / Winter 2014 Table of Contents Michael J. Fox and his wife, actress Tracy Pollan, founded the ...

Enhanced yield of phenolic extracts from banana peels (Musa acuminata Colla AAA) and cinnamon barks (Cinnamomum varum) and their antioxidative potentials in fish oil.

Science.gov (United States)

Anal, Anil Kumar; Jaisanti, Sirorat; Noomhorm, Athapol

2014-10-01

The bioactive compounds of banana peels and cinnamon barks were extracted by vacuum microwave and ultrasonic-assisted extraction methods at pre-determined temperatures and times. These methods enhance the yield extracts in shorter time. The highest yields of both extracts were obtained from the conditions which employed the highest temperature and the longest time. The extracts' yield from cinnamon bark method was higher by ultrasonic than vacuum microwave method, while vacuum microwave method gave higher extraction yield from banana peel than ultrasonic method. The phenolic contents of cinnamon bark and banana peel extracts were 467 and 35 mg gallic acid equivalent/g extract, respectively. The flavonoid content found in banana peel and cinnamon bark extracts were 196 and 428 mg/g quercetin equivalent, respectively. In addition, it was found that cinnamon bark gave higher 2,2-Diphenyl-1-1 picryhydrazyl (DPPH) radical scavenging activity and total antioxidant activity (TAA). The antioxidant activity of the extracts was analyzed by measuring the peroxide and p-anisidine values after oxidation of fish oils, stored for a month (30 days) at 25 °C and showed lesser peroxide and p-anisidine values in the fish oils containing the sample extracts in comparison to the fish oil without containing any extract. The banana peel and cinnamon extracts had shown the ability as antioxidants to prevent the oxidation of fish oil and might be considered as rich sources of natural antioxidant.

The effect of cinnamon extract and long-term aerobic training on heart function, biochemical alterations and lipid profile following exhaustive exercise in male rats.

Science.gov (United States)

Badalzadeh, Reza; Shaghaghi, Mehrnoush; Mohammadi, Mustafa; Dehghan, Gholamreza; Mohammadi, Zeynab

2014-12-01

Regular training is suggested to offer a host of benefits especially on cardiovascular system. In addition, medicinal plants can attenuate oxidative stress-mediated damages induced by stressor insults. In this study, we investigated the concomitant effect of cinnamon extract and long-term aerobic training on cardiac function, biochemical alterations and lipid profile following exhaustive exercise. Male Wistar rats (250-300 g) were divided into five groups depending on receiving regular training, cinnamon bark extraction, none or both of them, and then encountered with an exhausted exercise in last session. An 8-week endurance training program was designed with a progressive increase in training speed and time. Myocardial hemodynamics was monitored using a balloon-tipped catheter inserted into left ventricles. Blood samples were collected for analyzing biochemical markers, lipid profiles and lipid-peroxidation marker, malondealdehyde (MDA). Trained animals showed an enhanced cardiac force and contractility similar to cinnamon-treated rats. Co-application of regular training and cinnamon had additive effect in cardiac hemodynamic (Ptraining and supplementation with cinnamon significantly decreased serum levels of total cholesterol, low-density lipoprotein (LDL), and increased high-density lipoprotein (HDL) level and HDL/LDL ratio as compared to control group (Ptraining significantly reduced MDA level elevation induced by exhausted exercise (Ptraining improved cardiac hemodynamic through an additive effect. The positive effects of cinnamon and regular training on cardiac function were associated with a reduced serum MDA level and an improved blood lipid profile.

Evaluation of anti-diabetic effects of hydroalcoholic extract of green tea and cinnamon on streptozotocin-induced diabetic rats

OpenAIRE

Ghasem Shokri; Hamed Fathi; Majid Jafari Sabet; Nafiseh Nasri Nasrabadi; Ramin Ataee

2015-01-01

Today diabetes is one of the most common diseases in the world that affects half of the world population. The use of medicinal herbs especially green tea and cinnamon has been taken into consideration for relieving the symptoms of diabetes, but there were some different ideas about their effectiveness. So, this study was conducted to evaluate the effect of cinnamon and green tea extract, individually and in combination, on blood glucose and weight loss in diabetic mice with Streptozotocin (ST...

Methods for the synthesis of donor-acceptor cyclopropanes

Science.gov (United States)

Tomilov, Yu V.; Menchikov, L. G.; Novikov, R. A.; Ivanova, O. A.; Trushkov, I. V.

2018-03-01

The interest in cyclopropane derivatives is caused by the facts that, first, the three-carbon ring is present in quite a few natural and biologically active compounds and, second, compounds with this ring are convenient building blocks for the synthesis of diverse molecules (acyclic, alicyclic and heterocyclic). The carbon–carbon bonds in cyclopropane are kinetically rather inert; hence, they need to be activated to be involved in reactions. An efficient way of activation is to introduce vicinal electron-donating and electron-withdrawing substituents into the ring; these substrates are usually referred to as donor-acceptor cyclopropanes. This review gives a systematic account of the key methods for the synthesis of donor-acceptor cyclopropanes. The most important among them are reactions of nucleophilic alkenes with diazo compounds and iodonium ylides and approaches based on reactions of electrophilic alkenes with sulfur ylides (the Corey–Chaykovsky reaction). Among other methods used for this purpose, noteworthy are cycloalkylation of CH-acids, addition of α-halocarbonyl compounds to alkenes, cyclization via 1,3-elimination, reactions of alkenes with halocarbenes followed by reduction, the Simmons–Smith reaction and some other. The scope of applicability and prospects of various methods for the synthesis of donor-acceptor cyclopropanes are discussed. The bibliography includes 530 references.

Antibacterial Effects of Cinnamon: From Farm to Food, Cosmetic and Pharmaceutical Industries

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Seyed Fazel Nabavi

2015-09-01

Full Text Available Herbs and spices have been used since ancient times, because of their antimicrobial properties increasing the safety and shelf life of food products by acting against foodborne pathogens and spoilage bacteria. Plants have historically been used in traditional medicine as sources of natural antimicrobial substances for the treatment of infectious disease. Therefore, much attention has been paid to medicinal plants as a source of alternative antimicrobial strategies. Moreover, due to the growing demand for preservative-free cosmetics, herbal extracts with antimicrobial activity have recently been used in the cosmetic industry to reduce the risk of allergies connected to the presence of methylparabens. Some species belonging to the genus Cinnamomum, commonly used as spices, contain many antibacterial compounds. This paper reviews the literature published over the last five years regarding the antibacterial effects of cinnamon. In addition, a brief summary of the history, traditional uses, phytochemical constituents, and clinical impact of cinnamon is provided.

Antibacterial Effects of Cinnamon: From Farm to Food, Cosmetic and Pharmaceutical Industries

Science.gov (United States)

Nabavi, Seyed Fazel; Di Lorenzo, Arianna; Izadi, Morteza; Sobarzo-Sánchez, Eduardo; Daglia, Maria; Nabavi, Seyed Mohammad

2015-01-01

Herbs and spices have been used since ancient times, because of their antimicrobial properties increasing the safety and shelf life of food products by acting against foodborne pathogens and spoilage bacteria. Plants have historically been used in traditional medicine as sources of natural antimicrobial substances for the treatment of infectious disease. Therefore, much attention has been paid to medicinal plants as a source of alternative antimicrobial strategies. Moreover, due to the growing demand for preservative-free cosmetics, herbal extracts with antimicrobial activity have recently been used in the cosmetic industry to reduce the risk of allergies connected to the presence of methylparabens. Some species belonging to the genus Cinnamomum, commonly used as spices, contain many antibacterial compounds. This paper reviews the literature published over the last five years regarding the antibacterial effects of cinnamon. In addition, a brief summary of the history, traditional uses, phytochemical constituents, and clinical impact of cinnamon is provided. PMID:26378575

Tandem Knoevenagel–Michael reactions in aqueous diethylamine medium: A greener and efficient approach toward bis-dimedone derivatives

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Abdullah Mohammed Al-Majid

2017-02-01

The use of inexpensive, eco-friendly and readily available reagents, easy work-up, and high purity products makes the procedure a convenient and robust method for the synthesis of tandem Knoevenagel–Michael adducts.

On the effect of nuclear bridge modes on donor-acceptor electronic coupling in donor-bridge-acceptor molecules

International Nuclear Information System (INIS)

Davis, Daly; Toroker, Maytal Caspary; Speiser, Shammai; Peskin, Uri

2009-01-01

We report a theoretical study of intra-molecular electronic coupling in a symmetric DBA (donor-bridge-acceptor) complex, in which a donor electronic site is coupled to an acceptor site by way of intervening orbitals of a molecular bridge unit. In the off-resonant (deep tunneling) regime of electronic transport, the lowest unoccupied molecular orbitals (MO's) of the DBA system are split into distinguishable donor/acceptor and bridge orbitals. The effect of geometrical changes at the bridge on the donor/acceptor electronic energy manifold is studied for local stretching and bending modes. It is demonstrated that the energy splitting in the manifold of donor/acceptor unoccupied MOs changes in response to such changes, as assumed in simple McConnell-type models. Limitations of the simple models are revealed where the electronic charging of the bridge orbitals correlates with increasing donor/acceptor orbital energy splitting only for stretching but not for bending bridge modes.

The role of deep acceptor centers in the oxidation of acceptor-doped wide-band-gap perovskites ABO{sub 3}

Energy Technology Data Exchange (ETDEWEB)

Putilov, L.P., E-mail: lev.putilov@gmail.com; Tsidilkovski, V.I.

2017-03-15

The impact of deep acceptor centers on defect thermodynamics and oxidation of wide-band-gap acceptor-doped perovskites without mixed-valence cations is studied. These deep centers are formed by the acceptor-bound small hole polarons whose stabilization energy can be high enough (significantly higher than the hole-acceptor Coulomb interaction energy). It is shown that the oxidation enthalpy ΔH{sub ox} of oxide is determined by the energy ε{sub A} of acceptor-bound states along with the formation energy E{sub V} of oxygen vacancies. The oxidation reaction is demonstrated to be either endothermic or exothermic, and the regions of ε{sub A} and E{sub V} values corresponding to the positive or negative ΔH{sub ox} are determined. The contribution of acceptor-bound holes to the defect thermodynamics strongly depends on the acceptor states depth ε{sub A}: it becomes negligible at ε{sub A} less than a certain value (at which the acceptor levels are still deep). With increasing ε{sub A}, the concentration of acceptor-bound small hole polarons can reach the values comparable to the dopant content. The results are illustrated with the acceptor-doped BaZrO{sub 3} as an example. It is shown that the experimental data on the bulk hole conductivity of barium zirconate can be described both in the band transport model and in the model of hopping small polarons localized on oxygen ions away from the acceptor centers. Depending on the ε{sub A} magnitude, the oxidation reaction can be either endothermic or exothermic for both mobility mechanisms.

Michael Wood’s Yangzhou Dream

Institute of Scientific and Technical Information of China (English)

Yuan; Dan

2014-01-01

<正>Mr.Michael Wood is a wellknown British historian and documentary maker who has produced more than a hundred documentaries on various national histories and cultures exemplified by The Story of India.They enjoy wide popularity in more than 150 countries.I met him in February when he took his fi lm crew to Yangzhou to shoot The Story of China documentary for the British Broadcasting Corporation(BBC).It was a snowy day,cold and wet,but Michael said happily that the

Acceptors in ZnO

Energy Technology Data Exchange (ETDEWEB)

McCluskey, Matthew D., E-mail: mattmcc@wsu.edu; Corolewski, Caleb D.; Lv, Jinpeng; Tarun, Marianne C.; Teklemichael, Samuel T. [Department of Physics and Astronomy, Washington State University, Pullman, Washington 99164-2814 (United States); Walter, Eric D. [Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, Washington 99352 (United States); Norton, M. Grant; Harrison, Kale W. [School of Mechanical and Materials Engineering, Washington State University, Pullman, Washington 99164-2920 (United States); Ha, Su [Voiland School of Chemical Engineering and Bioengineering, Washington State University, Pullman, Washington 99164-6515 (United States)

2015-03-21

Zinc oxide (ZnO) has potential for a range of applications in the area of optoelectronics. The quest for p-type ZnO has focused much attention on acceptors. In this paper, Cu, N, and Li acceptor impurities are discussed. Experimental evidence indicates these point defects have acceptor levels 3.2, 1.4, and 0.8 eV above the valence-band maximum, respectively. The levels are deep because the ZnO valence band is quite low compared to conventional, non-oxide semiconductors. Using MoO{sub 2} contacts, the electrical resistivity of ZnO:Li was measured and showed behavior consistent with bulk hole conduction for temperatures above 400 K. A photoluminescence peak in ZnO nanocrystals is attributed to an acceptor, which may involve a Zn vacancy. High field (W-band) electron paramagnetic resonance measurements on the nanocrystals revealed an axial center with g{sub ⊥} = 2.0015 and g{sub //} = 2.0056, along with an isotropic center at g = 2.0035.

Subjectivity and Cultural Adjustment in Mathematics Education: A Response to Wolff-Michael Roth

Science.gov (United States)

Brown, Tony

2012-01-01

In this volume, Wolff-Michael Roth provides a critical but partial reading of Tony Brown's book "Mathematics Education and Subjectivity". The reading contrasts Brown's approach with Roth's own conception of subjectivity as derived from the work of Vygotsky, in which Roth aims to "reunite" psychology and sociology. Brown's book, however, focuses on…

A Cinnamon-Derived Procyanidin Compound Displays Anti-HIV-1 Activity by Blocking Heparan Sulfate- and Co-Receptor- Binding Sites on gp120 and Reverses T Cell Exhaustion via Impeding Tim-3 and PD-1 Upregulation.

Directory of Open Access Journals (Sweden)

Bridgette Janine Connell

Full Text Available Amongst the many strategies aiming at inhibiting HIV-1 infection, blocking viral entry has been recently recognized as a very promising approach. Using diverse in vitro models and a broad range of HIV-1 primary patient isolates, we report here that IND02, a type A procyanidin polyphenol extracted from cinnamon, that features trimeric and pentameric forms displays an anti-HIV-1 activity against CXCR4 and CCR5 viruses with 1-7 μM ED50 for the trimer. Competition experiments, using a surface plasmon resonance-based binding assay, revealed that IND02 inhibited envelope binding to CD4 and heparan sulphate (HS as well as to an antibody (mAb 17b directed against the gp120 co-receptor binding site with an IC50 in the low μM range. IND02 has thus the remarkable property of simultaneously blocking gp120 binding to its major host cell surface counterparts. Additionally, the IND02-trimer impeded up-regulation of the inhibitory receptors Tim-3 and PD-1 on CD4+ and CD8+ cells, thereby demonstrating its beneficial effect by limiting T cell exhaustion. Among naturally derived products significantly inhibiting HIV-1, the IND02-trimer is the first component demonstrating an entry inhibition property through binding to the viral envelope glycoprotein. These data suggest that cinnamon, a widely consumed spice, could represent a novel and promising candidate for a cost-effective, natural entry inhibitor for HIV-1 which can also down-modulate T cell exhaustion markers Tim-3 and PD-1.

Fluorescence quenching of derivatives of anthracene by organic electron donors and acceptors in acetonitrile. Electron and proton transfer mechanism

Science.gov (United States)

Mac, Marek; Najbar, Jan; Wirz, Jakob

1995-03-01

Fluorescence quenching of anthracene derivatives by organic electron donors (amines) and acceptors was investigated using stationary fluorescence measurements. The dependence of log( kq) on Δ Get shows Rehm-Weller-type behavior. The formation of anion radicals of anthracene, bianthryl, and 9-cyanoanthracene was detected by flash photolysis in systems containing aromatic amines (aniline, 2-bromoaniline, 4-bromoaniline, N,N-dimethylaniline, 4-bromo-N,N-dimethylaniline, N,N-diethylaniline, and 1,4-diazabicyclo[2.2.2]octane). The radical yields decreased and triplet yields increased when bromo derivatives of amines were used as donor quenchers, indicating the heavy-atom effect on spin conversion within radical pairs. The importance of the heavy-atom effect decreased when the energy gap between the charge transfer and molecular triplet states was small. The formation of separated radicals decreased when primary amines were used as quenchers which indicated the existence of an additional path of deactivation of the radical pair. The behavior of amines as quenchers of bianthryl and anthracene is compared with that of inorganic anion quenchers.

Blinking fluorescence of single donor-acceptor pairs: important role of "dark'' states in resonance energy transfer via singlet levels.

Science.gov (United States)

Osad'ko, I S; Shchukina, A L

2012-06-01

The influence of triplet levels on Förster resonance energy transfer via singlet levels in donor-acceptor (D-A) pairs is studied. Four types of D-A pair are considered: (i) two-level donor and two-level acceptor, (ii) three-level donor and two-level acceptor, (iii) two-level donor and three-level acceptor, and (iv) three-level donor and three-level acceptor. If singlet-triplet transitions in a three-level acceptor molecule are ineffective, the energy transfer efficiency E=I_{A}/(I_{A}+I_{D}), where I_{D} and I_{A} are the average intensities of donor and acceptor fluorescence, can be described by the simple theoretical equation E(F)=FT_{D}/(1+FT_{D}). Here F is the rate of energy transfer, and T_{D} is the donor fluorescence lifetime. In accordance with the last equation, 100% of the donor electronic energy can be transferred to an acceptor molecule at FT_{D}≫1. However, if singlet-triplet transitions in a three-level acceptor molecule are effective, the energy transfer efficiency is described by another theoretical equation, E(F)=F[over ¯](F)T_{D}/[1+F[over ¯](F)T_{D}]. Here F[over ¯](F) is a function of F depending on singlet-triplet transitions in both donor and acceptor molecules. Expressions for the functions F[over ¯](F) are derived. In this case the energy transfer efficiency will be far from 100% even at FT_{D}≫1. The character of the intensity fluctuations of donor and acceptor fluorescence indicates which of the two equations for E(F) should be used to find the value of the rate F. Therefore, random time instants of photon emission in both donor and acceptor fluorescence are calculated by the Monte Carlo method for all four types of D-A pair. Theoretical expressions for start-stop correlators (waiting time distributions) in donor and acceptor fluorescence are derived. The probabilities w_{N}^{D}(t) and w_{N}^{A}(t) of finding N photons of donor and acceptor fluorescence in the time interval t are calculated for various values of the energy

Near infrared organic light-emitting diodes based on acceptor-donor-acceptor (ADA) using novel conjugated isatin Schiff bases

International Nuclear Information System (INIS)

Taghi Sharbati, Mohammad; Soltani Rad, Mohammad Navid; Behrouz, Somayeh; Gharavi, Alireza; Emami, Farzin

2011-01-01

Fabrications of a single layer organic light emitting diodes (OLEDs) based on two conjugated acceptor-donor-acceptor (ADA) isatin Schiff bases are described. The electroluminescent spectra of these materials range from 630 to 700 nm and their band gaps were measured between 1.97 and 1.77 eV. The measured maximum external quantum efficiencies (EQE) for fabricated OLEDs are 0.0515% and 0.054% for two acceptor-donor-acceptor chromophores. The Commission International De L'Eclairage (CIE) (1931) coordinates of these two compounds were attained and found to be (0.4077, 0.4128) and (0.4411, 0.4126) for two used acceptor-donor-acceptor chromophores. The measured I-V curves demonstrated the apparent diode behavior of two ADA chromophores. The turn-on voltages in these OLEDs are directly dependent on the thickness. These results have demonstrated that ADA isatin Schiff bases could be considered as promising electroluminescence-emitting materials for fabrication of OLEDs.

Aqueous Cinnamon Extract (ACE-c) from the bark of Cinnamomum cassia causes apoptosis in human cervical cancer cell line (SiHa) through loss of mitochondrial membrane potential

International Nuclear Information System (INIS)

Koppikar, Soumya J; Choudhari, Amit S; Suryavanshi, Snehal A; Kumari, Shweta; Chattopadhyay, Samit; Kaul-Ghanekar, Ruchika

2010-01-01

Chemoprevention, which includes the use of synthetic or natural agents (alone or in combination) to block the development of cancer in human beings, is an extremely promising strategy for cancer prevention. Cinnamon is one of the most widely used herbal medicines with diverse biological activities including anti-tumor activity. In the present study, we have reported the anti-neoplastic activity of cinnamon in cervical cancer cell line, SiHa. The aqueous cinnamon extract (ACE-c) was analyzed for its cinnamaldehyde content by HPTLC analysis. The polyphenol content of ACE-c was measured by Folin-Ciocalteau method. Cytotoxicity analysis was performed by MTT assay. We studied the effect of cinnamon on growth kinetics by performing growth curve, colony formation and soft agar assays. The cells treated with ACE-c were analyzed for wound healing assay as well as for matrix metalloproteinase-2 (MMP-2) expression at mRNA and protein level by RT-PCR and zymography, respectively. Her-2 protein expression was analyzed in the control and ACE-c treated samples by immunoblotting as well as confocal microscopy. Apoptosis studies and calcium signaling assays were analyzed by FACS. Loss of mitochondrial membrane potential (Δψ m ) in cinnamon treated cells was studied by JC-1 staining and analyzed by confocal microscopy as well as FACS. Cinnamon alters the growth kinetics of SiHa cells in a dose-dependent manner. Cells treated with ACE-c exhibited reduced number of colonies compared to the control cells. The treated cells exhibited reduced migration potential that could be explained due to downregulation of MMP-2 expression. Interestingly, the expression of Her-2 oncoprotein was significantly reduced in the presence of ACE-c. Cinnamon extract induced apoptosis in the cervical cancer cells through increase in intracellular calcium signaling as well as loss of mitochondrial membrane potential. Cinnamon could be used as a potent chemopreventive drug in cervical cancer

Aqueous Cinnamon Extract (ACE-c from the bark of Cinnamomum cassia causes apoptosis in human cervical cancer cell line (SiHa through loss of mitochondrial membrane potential

Directory of Open Access Journals (Sweden)

Chattopadhyay Samit

2010-05-01

Full Text Available Abstract Background Chemoprevention, which includes the use of synthetic or natural agents (alone or in combination to block the development of cancer in human beings, is an extremely promising strategy for cancer prevention. Cinnamon is one of the most widely used herbal medicines with diverse biological activities including anti-tumor activity. In the present study, we have reported the anti-neoplastic activity of cinnamon in cervical cancer cell line, SiHa. Methods The aqueous cinnamon extract (ACE-c was analyzed for its cinnamaldehyde content by HPTLC analysis. The polyphenol content of ACE-c was measured by Folin-Ciocalteau method. Cytotoxicity analysis was performed by MTT assay. We studied the effect of cinnamon on growth kinetics by performing growth curve, colony formation and soft agar assays. The cells treated with ACE-c were analyzed for wound healing assay as well as for matrix metalloproteinase-2 (MMP-2 expression at mRNA and protein level by RT-PCR and zymography, respectively. Her-2 protein expression was analyzed in the control and ACE-c treated samples by immunoblotting as well as confocal microscopy. Apoptosis studies and calcium signaling assays were analyzed by FACS. Loss of mitochondrial membrane potential (Δψm in cinnamon treated cells was studied by JC-1 staining and analyzed by confocal microscopy as well as FACS. Results Cinnamon alters the growth kinetics of SiHa cells in a dose-dependent manner. Cells treated with ACE-c exhibited reduced number of colonies compared to the control cells. The treated cells exhibited reduced migration potential that could be explained due to downregulation of MMP-2 expression. Interestingly, the expression of Her-2 oncoprotein was significantly reduced in the presence of ACE-c. Cinnamon extract induced apoptosis in the cervical cancer cells through increase in intracellular calcium signaling as well as loss of mitochondrial membrane potential. Conclusion Cinnamon could be used as a

Creatine co-ingestion with carbohydrate or cinnamon extract provides no added benefit to anaerobic performance.

Science.gov (United States)

Islam, Hashim; Yorgason, Nick J; Hazell, Tom J

2016-09-01

The insulin response following carbohydrate ingestion enhances creatine transport into muscle. Cinnamon extract is promoted to have insulin-like effects, therefore this study examined if creatine co-ingestion with carbohydrates or cinnamon extract improved anaerobic capacity, muscular strength, and muscular endurance. Active young males (n = 25; 23.7 ± 2.5 y) were stratified into 3 groups: (1) creatine only (CRE); (2) creatine+ 70 g carbohydrate (CHO); or (3) creatine+ 500 mg cinnamon extract (CIN), based on anaerobic capacity (peak power·kg(-1)) and muscular strength at baseline. Three weeks of supplementation consisted of a 5 d loading phase (20 g/d) and a 16 d maintenance phase (5 g/d). Pre- and post-supplementation measures included a 30-s Wingate and a 30-s maximal running test (on a self-propelled treadmill) for anaerobic capacity. Muscular strength was measured as the one-repetition maximum 1-RM for chest, back, quadriceps, hamstrings, and leg press. Additional sets of the number of repetitions performed at 60% 1-RM until fatigue measured muscular endurance. All three groups significantly improved Wingate relative peak power (CRE: 15.4% P = .004; CHO: 14.6% P = .004; CIN: 15.7%, P = .003), and muscular strength for chest (CRE: 6.6% P creatine ingestion lead to similar changes in anaerobic power, strength, and endurance.

Polymer solar cells based on poly(3-hexylthiophene) and fullerene: Pyrene acceptor systems

Energy Technology Data Exchange (ETDEWEB)

Cominetti, Alessandra; Pellegrino, Andrea; Longo, Luca [Research Center for Renewable Energies and Environment, Istituto Donegani, Eni S.p.A, Via Fauser 4, IT-28100 Novara (Italy); Po, Riccardo, E-mail: riccardo.po@eni.com [Research Center for Renewable Energies and Environment, Istituto Donegani, Eni S.p.A, Via Fauser 4, IT-28100 Novara (Italy); Tacca, Alessandra; Carbonera, Chiara; Salvalaggio, Mario [Research Center for Renewable Energies and Environment, Istituto Donegani, Eni S.p.A, Via Fauser 4, IT-28100 Novara (Italy); Baldrighi, Michele; Meille, Stefano Valdo [Dipartimento di Chimica, Materiali e Ingegneria Chimica “G. Natta”, Politecnico di Milano, via Mancinelli 7, IT-20131 Milano (Italy)

2015-06-01

The replacement of widely used fullerene derivatives, e.g. [6,6]-phenyl-C61-butyric acid methyl ester (PCBM), with unfunctionalized C60 and C70 is an effective approach to reduce the costs of organic photovoltaics. However, solubility issues of these compounds have always represented an obstacle to their use. In this study, bulk-heterojunction solar cells made of poly(3-hexylthiophene) donor polymer, C60 or C70 acceptors and a pyrene derivative (1-pyrenebutiric acid butyl ester) are reported. Butyl 1-pyrenebutirate limits the aggregation of fullerenes and improves the active layer morphology, plausibly due to the formation of pyrene-fullerene complexes which, in the case of pyrene-C70, were also obtained in a crystalline form. Maximum power conversion efficiencies of 1.54% and 2.50% have been obtained using, respectively, C60 or C70 as acceptor. Quantum mechanical modeling provides additional insight into the formation of plausible supermolecular structures via π-π interactions and on the redox behaviour of pyrene-fullerene systems. - Highlights: • Pyrene derivatives favour the dispersion of unfunctionalized fullerenes. • Polymer solar cells with pyrene: C60 adduct as acceptor have efficiencies of 1.54%. • When C60 is substituted with C70 the efficiency is increased to 2.50%. • DFT calculations support the plausibility of the formation of pyrene: fullerene adducts. • The use of unfunctionalized fullerenes may decrease the costs of polymer solar cells.

The Hypoglycemic and Antioxidant Activity of Cress Seed and Cinnamon on Streptozotocin Induced Diabetes in Male Rats

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Safaa Qusti

2016-01-01

Full Text Available The present study aimed to estimate the stimulation of pancreas of rats with streptozotocin induced diabetes using 20% (w/w garden cress seed (Lepidium sativum and cinnamon methanol extracts. The positive control diabetic group showed a significant increase in fasting blood sugar, lipid peroxide, interleukin-6, carboxymethyl lysine, serum uric acid, urea, creatinine, immunoglobulins, and urine albumin and a significant decrease in antioxidant enzymes, sodium ions, potassium ions, and urine creatinine. Severe histopathological changes in the kidney and pancreas tissues in hyperglycemic rats were also shown in the positive control diabetic group. Meanwhile, the groups that were treated with 20% garden cress seed and cinnamon methanol extracts showed a significant decrease in fasting blood sugar and all elevated abovementioned biochemical parameters and an increase in the lowered ones restoring them nearly to the normal levels of G1. Kidney and pancreas tissues were also ameliorated and restored nearly to the normal status. Both garden cress seed and cinnamon methanol extracts succeeded in controlling hyperglycemia in rats with streptozotocin induced diabetes and ameliorated the biochemical and histopathological changes because of their antioxidant activity acquired by their possession of phenolic phytochemicals.

Energy transfer ultraviolet photodetector with 8-hydroxyquinoline derivative-metal complexes as acceptors

International Nuclear Information System (INIS)

Wu Shuang-Hong; Chen Zhi; Li Shi-Bin; Wang Xiao-Hui; Wei Xiong-Bang; Li Wen-Lian

2015-01-01

We choose 8-hydroxyquinoline derivative-metal complexes (Beq, Mgq, and Znq) as the acceptors (A) and 4,4',4”-tri-(2-methylphenyl phenylamino) triphenylaine (m-MTDATA) as the donor (D) respectively to study the existing energy transfer process in the organic ultraviolet (UV) photodetector (PD), which has an important influence on the sensitivity of PDs. The energy transfer process from D to A without exciplex formation is discussed, differing from the working mechanism of previous PDs with Gaq [Zisheng Su, Wenlian Li, Bei Chu, Tianle Li, Jianzhuo Zhu, Guang Zhang, Fei Yan, Xiao Li, Yiren Chen and Chun-Sing Lee 2008 Appl. Phys. Lett. 93 103309)] and REq [J. B. Wang, W. L. Li, B. Chu, L. L. Chen, G. Zhang, Z. S. Su, Y. R. Chen, D. F. Yang, J. Z. Zhu, S. H. Wu, F. Yan, H. H. Liu, C. S. Lee 2010 Org. Electron. 11 1301] used as an A material. Under 365-nm UV irradiation with an intensity of 1.2 mW/cm 2 , the m-MTDATA:Beq blend device with a weight ratio of 1:1 shows a response of 192 mA/W with a detectivity of 6.5× 10 11 Jones, which exceeds those of PDs based on Mgq (146 mA/W) and Znq (182 mA/W) due to better energy level alignment between m-MTDATA/Beq and lower radiative decay. More photophysics processes of the PDs involved are discussed in detail. (paper)

Michael De Sousa (1989 - 2012)

CERN Multimedia

2012-01-01

We are deeply saddened to announce the death of Mr Michael De Sousa on 13 May 2012. Mr De Sousa, who was born on 02.09.1989, was working as an apprentice in the TE Department and had been at CERN since 24.08.2009. The Director-General has sent a message of condolence to his family on behalf of the CERN personnel. Social Affairs Human Resources Department     It is with great emotion and deep sadness that we learn of the tragic loss of our colleague and friend Michael De Sousa. Michael was a hard working colleague, cordial and considerate. Within a few months, he marked his presence by the implementation of the instrumentation benches for gas permeation measurement in polymers, and the calibration of high technology gas analyzers, necessary for vacuum technology. His last contribution will enable us to measure pressures in the extreme high vacuum range for the ELENA project.  With the continuation of this activity, his memory will remain. His accomplishments will remain...

Effect of hydro-ethanolic extracts of cinnamon (Cinnamomum zeylanicum Blume and common horsetail (Equisetum arvense L. on incidence and severity of Botrytis cinerea on strawberry

Directory of Open Access Journals (Sweden)

Pazmiño-Miranda Pilar

2017-05-01

Full Text Available The effect of application of three dosages (5, 10 and 15 mL/L and two frequencies (each 6 and 8 days of ethanoic extracts obtained from cinnamon (Cinnamomum zeylanicum Blume and common horsetail (Equisetum arvense L. on incidence and severity of grey mould (Botrytis cinerea on strawberry crop (Fragaria ananassa cv. Albion was evaluated. Experiment was carried out in a randomized block design with factorial arrangement 2 x 3 x 2 + 1, with three replications. Lower incidence and severity percentage in flower and fruit (10.24 and 24.43%, respectively were observed after application of cinnamon extract at 15 mL/L at 6 days interval. Similarly, lower fruit severity (11.86% was observed with the same treatment. In general, reduction in B. cinerea incidence and severity was lower when common horsetail extract was used, compared to cinnamon extracts. According to our results, using of cinnamon hydro-ethanoic extracts could be considered as sustainable alternative for grey mold management in strawberry crops.

High-Performance All-Polymer Solar Cells Achieved by Fused Perylenediimide-Based Conjugated Polymer Acceptors.

Science.gov (United States)

Yin, Yuli; Yang, Jing; Guo, Fengyun; Zhou, Erjun; Zhao, Liancheng; Zhang, Yong

2018-05-09

We report three n-type polymeric electron acceptors (PFPDI-TT, PFPDI-T, and PFPDI-Se) based on the fused perylene diimide (FPDI) and thieno[3,2- b]thiophene, thiophene, or selenophene units for all-polymer solar cells (all-PSCs). These FPDI-based polymer acceptors exhibit strong absorption between 350 and 650 nm with wide optical bandgap of 1.86-1.91 eV, showing good absorption compensation with the narrow bandgap polymer donor. The lowest unoccupied molecular orbital (LUMO) energy levels were located at around -4.11 eV, which are comparable with those of the fullerene derivatives and other small molecular electron acceptors. The conventional all-PSCs based on the three polymer acceptors and PTB7-Th as polymer donor gave remarkable power conversion efficiencies (PCEs) of >6%, and the PFPDI-Se-based all-PSC achieved the highest PCE of 6.58% with a short-circuit current density ( J sc ) of 13.96 mA/cm 2 , an open-circuit voltage ( V oc ) of 0.76 V, and a fill factor (FF) of 62.0%. More interestingly, our results indicate that the photovoltaic performances of the FPDI-based polymer acceptors are mainly determined by the FPDI unit with a small effect from the comonomers, which is quite different from the others reported rylenediimide-based polymer acceptors. This intriguing phenomenon is speculated as the huge geometry configuration of the FPDI unit, which minimizes the effect of the comonomer. These results highlight a promising future for the application of the FPDI-based polymer acceptors in the highly efficient all-PSCs.

Stereoselective synthesis of diazaspiro[5.5]undecane derivatives via base promoted [5+1] double Michael addition of N,N-dimethylbarbituric acid to diaryliedene acetones

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Mohammad Shahidul Islam

2017-01-01

Full Text Available The nitrogen containing spiro-heterocycle is one of the privileged synthetic motif that constitutes various naturally occurring molecules and displays a broad range of pharmaceutical and biological activities. A new methodology was developed for the synthesis of 2,4-diazaspiro[5.5]undecane-1,3,5,9-tetraones spiro-heterocyclic derivatives via cascade cyclization of [5+1] double Michael addition reaction of N,N-dimethylbarbituric acid with the derivatives of diaryldivinylketones in the presence of diethylamine at ambient temperature. The developed protocol is highly capable of furnishing diazaspiro[5.5]undecane derivatives 3a–m in excellent yields (up to 98%, from easily accessible symmetric and non-symmetric divinylketones 2a–m, containing aryl and heteroaryl substituents. The diazaspiro-heterocyclic structure was mainly elucidated by NMR and X-ray crystallographic techniques. The single-crystal X-ray studies revealed that, the cyclohexanone unit of spirocycles often prefers a chair conformation rather than twisted conformation. The intermolecular hydrogen bonding and CArH⋯π, π–π stacking interactions driving forces are mainly responsible for the crystal packing.

Cyclopropanation of 5-(1-Bromo-2-phenyl-vinyl-3-methyl-4-nitro-isoxazoles under Phase Transfer Catalysis (PTC Conditions

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Linda Piras

2015-04-01

Full Text Available Heavily substituted cyclopropane esters were prepared in high yields, complete diastereoselection and average (up to 58% enantioselectivity. The reaction described herein entailed reacting 4-nitro-5-bromostyrylisoxazoles, a class of powerful Michael acceptors with malonate esters under the catalysis of 5 mol% of a chincona derived phase-transfer catalyst.

Molecular design of novel fullerene-based acceptors for enhancing the open circuit voltage in polymer solar cells

Science.gov (United States)

Tajbakhsh, Mahmood; Kariminasab, Mohaddeseh; Ganji, Masoud Darvish; Alinezhad, Heshmatollah

2017-12-01

Organic solar cells, especially bulk hetero-junction polymer solar cells (PSCs), are the most successful structures for applications in renewable energy. The dramatic improvement in the performance of PSCs has increased demand for new conjugated polymer donors and fullerene derivative acceptors. In the present study, quantum chemical calculations were performed for several representative fullerene derivatives in order to determine their frontier orbital energy levels and electronic structures, thereby helping to enhance their performance in PSC devices. We found correlations between the theoretical lowest unoccupied molecular orbital levels and electrophilicity index of various fullerenes with the experimental open circuit voltage of photovoltaic devices according to the poly(3-hexylthiophene) (P3HT):fullerene blend. The correlations between the structure and descriptors may facilitate screening of the best fullerene acceptor for the P3HT donor. Thus, we considered fullerenes with new functional groups and we predicted the output factors for the corresponding P3HT:fullerene blend devices. The results showed that fullerene derivatives based on thieno-o-quinodimethane-C60 with a methoxy group will have enhanced photovoltaic properties. Our results may facilitate the design of new fullerenes and the development of favorable acceptors for use in photovoltaic applications.

Pentanidium-catalyzed enantioselective phase-transfer conjugate addition reactions

KAUST Repository

Ma, Ting

2011-03-09

A new chiral entity, pentanidium, has been shown to be an excellent chiral phase-transfer catalyst. The enantioselective Michael addition reactions of tert-butyl glycinate-benzophenone Schiff base with various α,β- unsaturated acceptors provide adducts with high enantioselectivities. A successful gram-scale experiment at a low catalyst loading of 0.05 mol % indicates the potential for practical applications of this methodology. Phosphoglycine ester analogues can also be utilized as the Michael donor, affording enantioenriched α-aminophosphonic acid derivatives and phosphonic analogues of (S)-proline. © 2011 American Chemical Society.

Antimicrobial effect of cinnamon (Cinnamomum verum J. Presl bark essential oil in cream-filled cakes and pastries

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M. Vazirian

2015-11-01

Full Text Available Background and objectives: Food poisoning has been always a major concern in health system of every community and cream-filled products are one of the most widespread food poisoning causes in humans. In present study, we examined the preservative effect of the cinnamon oil in cream-filled cakes. Methods: Antimicrobial activity of Cinnamomum verum J. Presl (Cinnamon bark essential oil was examined against five food-borne pathogens (Staphylococcus aureus, Escherichia coli, Candida albicans, Bacillus cereus and Salmonella typhimurium to investigate its potential for use as a natural preservative in cream-filled baked goods. Chemical constituents of the oil were determined by gas chromatography/mass spectrometry. For evaluation of preservative sufficiency of the oil, pathogens were added to cream-filled cakes manually and 1 μL/mL of the essential oil was added to all samples except the blank.  Results: Chemical constituents of the oil were determined by gas chromatography/mass spectrometry and twenty five components were identified where cinnamaldehyde (79.73%, linalool (4.08%, cinnamaldehyde para-methoxy (2.66%, eugenol (2.37% and trans-caryophyllene (2.05% were the major constituents. Cinnamon essential oil showed strong antimicrobial activity against selected pathogens in vitro and the minimum inhibitory concentration values against all tested microorganisms were determined as 0.5 μL/disc except for S. aureus for which, the oil was not effective in tested concentrations. After baking, no observable microorganism was observed in all susceptible microorganisms count in 72h stored samples.  Conclusion: It was concluded that by analysing the sensory quality of the preserved food, cinnamon oil may be considered as a natural preservative in food industry, especially for cream-filled cakes and pastries.

Conjugated donor-acceptor-acceptor (D-A-A) molecule for organic nonvolatile resistor memory.

Science.gov (United States)

Dong, Lei; Li, Guangwu; Yu, An-Dih; Bo, Zhishan; Liu, Cheng-Liang; Chen, Wen-Chang

2014-12-01

A new donor-acceptor-acceptor (D-A-A) type of conjugated molecule, N-(4-(N',N'-diphenyl)phenylamine)-4-(4'-(2,2-dicyanovinyl)phenyl) naphthalene-1,8-dicarboxylic monoimide (TPA-NI-DCN), consisting of triphenylamine (TPA) donors and naphthalimide (NI)/dicyanovinylene (DCN) acceptors was synthesized and characterized. In conjunction with previously reported D-A based materials, the additional DCN moiety attached as end group in the D-A-A configuration can result in a stable charge transfer (CT) and charge-separated state to maintain the ON state current. The vacuum-deposited TPA-NI-DCN device fabricated as an active memory layer was demonstrated to exhibit write-once-read-many (WORM) switching characteristics of organic nonvolatile memory due to the strong polarity of the TPA-NI-DCN moiety. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Effects of Essential Oils from Thyme, Cinnamon and Clove on Mycelial Growth of Colletotrichum acutatum

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Nataša Duduk

2010-01-01

Full Text Available Effects of the volatile phase of thyme, cinnamon and clove essential oils onColletotrichum acutatum were investigated. Mycelial disc was placed in the center of thePetri dish (V=66 ml containing PDA. Different volumes of either non- or ethanol-dilutedessential oils were placed on the inner side of the dish cover to obtain final concentrationsof 153, 107, 76, 46, 15, 14, 12, 11, 7.6, 3.82, 1.53, 0.153 and 0.0153 μl/L of air. The dishes were sealed with Parafilm and incubated in up-side-down position. After 7 days of incubation,mycelial growth was recorded by measuring the colony diameter. If no mycelial growthwas recorded, the disc was transferred to a new PDA plate in order to evaluate whetherthe activity was either fungistatic or fungicidal. Mean growth values were obtained andthen converted to inhibition percentage of mycelial growth compared with the controltreatment. All the tested essential oils inhibited mycelial growth of C. acutatum in the dosedependent manner. Mycelial growth was totally inhibited by thyme oil in the concentrationof 76 μl/L of air. The same results were obtained by cinnamon and clove oil in the concentrationof 107 μl/L of air. Thyme and cinnamon oil had fungicidal effect in concentrationsof 107 and 153 μl/L respectively. The results obtained provide evidence on the antifungalin vitro effect of the tested essential oils as potential means for the control of C. acutatum.

Non-fullerene electron acceptors for organic photovoltaic devices

Energy Technology Data Exchange (ETDEWEB)

Jenekhe, Samson A.; Li, Haiyan; Earmme, Taeshik; Ren, Guoqiang

2017-11-07

Non-fullerene electron acceptors for highly efficient organic photovoltaic devices are described. The non-fullerene electron acceptors have an extended, rigid, .pi.-conjugated electron-deficient framework that can facilitate exciton and charge derealization. The non-fullerene electron acceptors can physically mix with a donor polymer and facilitate improved electron transport. The non-fullerene electron acceptors can be incorporated into organic electronic devices, such as photovoltaic cells.

Energy transfer ultraviolet photodetector with 8-hydroxyquinoline derivative-metal complexes as acceptors

Science.gov (United States)

Wu, Shuang-Hong; Li, Wen-Lian; Chen, Zhi; Li, Shi-Bin; Wang, Xiao-Hui; Wei, Xiong-Bang

2015-02-01

We choose 8-hydroxyquinoline derivative-metal complexes (Beq, Mgq, and Znq) as the acceptors (A) and 4,4',4”-tri-(2-methylphenyl phenylamino) triphenylaine (m-MTDATA) as the donor (D) respectively to study the existing energy transfer process in the organic ultraviolet (UV) photodetector (PD), which has an important influence on the sensitivity of PDs. The energy transfer process from D to A without exciplex formation is discussed, differing from the working mechanism of previous PDs with Gaq [Zisheng Su, Wenlian Li, Bei Chu, Tianle Li, Jianzhuo Zhu, Guang Zhang, Fei Yan, Xiao Li, Yiren Chen and Chun-Sing Lee 2008 Appl. Phys. Lett. 93 103309)] and REq [J. B. Wang, W. L. Li, B. Chu, L. L. Chen, G. Zhang, Z. S. Su, Y. R. Chen, D. F. Yang, J. Z. Zhu, S. H. Wu, F. Yan, H. H. Liu, C. S. Lee 2010 Org. Electron. 11 1301] used as an A material. Under 365-nm UV irradiation with an intensity of 1.2 mW/cm2, the m-MTDATA:Beq blend device with a weight ratio of 1:1 shows a response of 192 mA/W with a detectivity of 6.5× 1011 Jones, which exceeds those of PDs based on Mgq (146 mA/W) and Znq (182 mA/W) due to better energy level alignment between m-MTDATA/Beq and lower radiative decay. More photophysics processes of the PDs involved are discussed in detail. Project supported by the National Natural Science Foundation of China (Grant Nos. 61371046, 61405026, 61474016, and 61421002) and China Postdoctoral Science Foundation (Grant No. 2014M552330).

Michael Faraday's Bicentenary.

Science.gov (United States)

Williams, L. Pearce; And Others

1991-01-01

Six articles discuss the work of Michael Faraday, a chemist whose work revolutionized physics and led directly to both classical field and relativity theory. The scientist as a young man, the electromagnetic experiments of Faraday, his search for the gravelectric effect, his work on optical glass, his laboratory notebooks, and his creative use of…

Lipid Oxidation, Color Changes, and Microbiological Quality of Frozen Beef Burgers Incorporated with Shirazi Thyme, Cinnamon, and Rosemary Extracts

Directory of Open Access Journals (Sweden)

Hadi Hashemi Gahruie

2017-01-01

Full Text Available In this study, the oxidative stability of beef burgers incorporated with Shirazi thyme, cinnamon, and rosemary extracts was compared with that of BHT-incorporated and antioxidant-free samples. The chemical composition, TBARS, metmyoglobin, pH, color, and microbial and sensory characteristics were evaluated during storage at −18°C for 2 months. The results indicated that Shirazi thyme and cinnamon extracts did not change the colorimetric properties significantly (P BHT > Shirazi thyme > rosemary > control. Finally, the results showed that these plant extracts can be utilized as an alternative to synthetic antioxidants in formulation of burgers.

The anti-translocation and anti-inflammatory effect of cinnamon oil in mice with TNBS induced colitis

Czech Academy of Sciences Publication Activity Database

Bujňáková, D.; Juhás, Štefan; Faix, Š.

2013-01-01

Roč. 68, č. 5 (2013), s. 1000-1003 ISSN 0006-3088 Institutional support: RVO:67985904 Keywords : bacterial translocation * E. coli * colitis * cinnamon oil Subject RIV: CE - Biochemistry Impact factor: 0.696, year: 2013

Insect-resistant food packaging film development using cinnamon oil and microencapsulation technologies.

Science.gov (United States)

Kim, In-Hah; Han, Jaejoon; Na, Ja Hyun; Chang, Pahn-Sik; Chung, Myung Sub; Park, Ki Hwan; Min, Sea C

2013-02-01

Insect-resistant films containing a microencapsulated insect-repelling agent were developed to protect food products from the Indian meal moth (Plodia interpunctella). Cinnamon oil (CO), an insect repelling agent, was encapsulated with gum arabic, whey protein isolate (WPI)/maltodextrin (MD), or poly(vinyl alcohol) (PVA). A low-density polyethylene (LDPE) film was coated with an ink or a polypropylene (PP) solution that incorporated the microcapsules. The encapsulation efficiency values obtained with gum arabic, WPI/MD, and PVA were 90.4%, 94.6%, and 80.7%, respectively. The films containing a microcapsule emulsion of PVA and CO or incorporating a microcapsule powder of WPI/MD and CO were the most effective (P packaging for food products. The insect-repelling effect of cinnamon oil incorporated into LDPE films was more effective with microencapsulation. The system developed in this research with LDPE film may also be extended to other food-packaging films where the same coating platform can be used. This platform is interchangeable and easy to use for the delivery of insect-repelling agents. The films can protect a wide variety of food products from invasion by the Indian meal moth. © 2013 Institute of Food Technologists®

Template Dimerization Promotes an Acceptor Invasion-Induced Transfer Mechanism during Human Immunodeficiency Virus Type 1 Minus-Strand Synthesis

OpenAIRE

Balakrishnan, Mini; Roques, Bernard P.; Fay, Philip J.; Bambara, Robert A.

2003-01-01

The biochemical mechanism of template switching by human immunodeficiency virus type 1 (HIV-1) reverse transcriptase and the role of template dimerization were examined. Homologous donor-acceptor template pairs derived from the HIV-1 untranslated leader region and containing the wild-type and mutant dimerization initiation sequences (DIS) were used to examine the efficiency and distribution of transfers. Inhibiting donor-acceptor interaction was sufficient to reduce transfers in DIS-containin...

Risk assessment of coumarin using the bench mark dose (BMD) approach: children in Norway which regularly eat oatmeal porridge with cinnamon may exceed the TDI for coumarin with several folds.

Science.gov (United States)

Fotland, T Ø; Paulsen, J E; Sanner, T; Alexander, J; Husøy, T

2012-03-01

Coumarin is a naturally occurring flavouring substance in cinnamon and many other plants. It is known that coumarin can cause liver toxicity in several species, and it is considered a non-genotoxic carcinogen in rodents. By using the bench mark dose approach we re-assessed coumarin toxicity and established a new TDI for coumarin of 0.07 mg/kg bw/day. Oral intake of coumarin is related to consumption of cinnamon-containing foods and food supplements. Cinnamon is a widely used spice in Norway, and can be used as topping on oatmeal porridge. Based on analyses of coumarin in Norwegian foods, intake calculations for children and adults were conducted, and a risk assessment of coumarin in the Norwegian population was performed. Intake estimates of coumarin show that small children eating oatmeal porridge several times a week sprinkled with cinnamon could have a coumarin intake of 1.63 mg/kg bw/day and may exceeding the TDI with several folds. Adults drinking cinnamon-based tea and consuming cinnamon supplements also can exceed TDI. The coumarin intake could exceed the TDI by 7- to 20-fold in some intake scenarios. Such large daily exceedances of TDI, even for a limited time period of 1-2 weeks, cause concern of adverse health effects. Copyright © 2011 Elsevier Ltd. All rights reserved.

Manipulation of Probiotics Fermentation of Yogurt by Cinnamon and Licorice: Effects on Yogurt Formation and Inhibition of Helicobacter Pylori Growth in vitro

OpenAIRE

S. Behrad; M.Y. Yusof; K. L. Goh; A.S. Baba

2009-01-01

Probiotic bacteria especially Lactobacillus spp. and Bifidobacterium exert suppressive effect on Helicobacter pylori. Cinnamon and licorice have been traditionally used for the treatment of gastric ulcer. The objectives of this study were to determine the effects of herbs on yogurt fermentation, the level of probiotic bacteria in yogurt during 28 days storage and the effect of herbal yogurt on the growth of H. pylori in vitro. Cinnamon or licorice was mixed with milk and the mixture was ferme...

Effect of oral cinnamon intervention on metabolic profile and body composition of Asian Indians with metabolic syndrome: a randomized double -blind control trial.

Science.gov (United States)

Gupta Jain, Sonal; Puri, Seema; Misra, Anoop; Gulati, Seema; Mani, Kalaivani

2017-06-12

Nutritional modulation remains central to the management of metabolic syndrome. Intervention with cinnamon in individuals with metabolic syndrome remains sparsely researched. We investigated the effect of oral cinnamon consumption on body composition and metabolic parameters of Asian Indians with metabolic syndrome. In this 16-week double blind randomized control trial, 116 individuals with metabolic syndrome were randomized to two dietary intervention groups, cinnamon [6 capsules (3 g) daily] or wheat flour [6 capsules (2.5 g) daily]. Body composition, blood pressure and metabolic parameters were assessed. Significantly greater decrease [difference between means, (95% CI)] in fasting blood glucose (mmol/L) [0.3 (0.2, 0.5) p = 0.001], glycosylated haemoglobin (mmol/mol) [2.6 (0.4, 4.9) p = 0.023], waist circumference (cm) [4.8 (1.9, 7.7) p = 0.002] and body mass index (kg/m2 ) [1.3 (0.9, 1.5) p = 0.001] was observed in the cinnamon group compared to placebo group. Other parameters which showed significantly greater improvement were: waist-hip ratio, blood pressure, serum total cholesterol, low-density lipoprotein cholesterol, serum triglycerides, and high-density lipoprotein cholesterol. Prevalence of defined metabolic syndrome was significantly reduced in the intervention group (34.5%) vs. the placebo group (5.2%). A single supplement intervention with 3 g cinnamon for 16 weeks resulted in significant improvements in all components of metabolic syndrome in a sample of Asian Indians in north India. The clinical trial was retrospectively registered (after the recruitment of the participants) in ClinicalTrial.gov under the identification number: NCT02455778 on 25th May 2015.

Indian meal moth (Plodia interpunctella)-resistant food packaging film development using microencapsulated cinnamon oil.

Science.gov (United States)

Kim, In-Hah; Song, Ah Young; Han, Jaejoon; Park, Ki Hwan; Min, Sea C

2014-10-01

Insect-resistant laminate films containing microencapsulated cinnamon oil (CO) were developed to protect food products from the Indian meal moth (Plodia interpunctella). CO microencapsulated with polyvinyl alcohol was incorporated with a printing ink and the ink mixture was applied to a low-density polyethylene (LDPE) film as an ink coating. The coated LDPE surface was laminated with a polypropylene film. The laminate film impeded the invasion of moth larvae and repelled the larvae. The periods of time during which cinnamaldehyde level in the film remained above a minimum repelling concentration, predicted from the concentration profile, were 21, 21, and 10 d for cookies, chocolate, and caramel, respectively. Coating with microencapsulated ink did not alter the tensile or barrier properties of the laminate film. Microencapsulation effectively prevented volatilization of CO. The laminate film can be produced by modern film manufacturing lines and applied to protect food from Indian meal moth damage. The LDPE-PP laminate film developed using microencapsulated cinnamon oil was effective to protect the model foods from the invasion of Indian meal moth larvae. The microencapsulated ink coating did not significantly change the tensile and barrier properties of the LDPE-PP laminate film, implying that replacement of the uncoated with coated laminate would not be an issue with current packaging equipment. The films showed the potential to be produced in commercial film production lines that usually involve high temperatures because of the improved thermal stability of cinnamon oil due to microencapsulation. The microencapsulated system may be extended to other food-packaging films for which the same ink-printing platform is used. © 2014 Institute of Food Technologists®

Electron Acceptor Materials Engineering in Colloidal Quantum Dot Solar Cells

KAUST Repository

Liu, Huan

2011-07-15

Lead sulfide colloidal quantum dot (CQD) solar cells with a solar power conversion efficiency of 5.6% are reported. The result is achieved through careful optimization of the titanium dioxide electrode that serves as the electron acceptor. Metal-ion-doped sol-gel-derived titanium dioxide electrodes produce a tunable-bandedge, well-passivated materials platform for CQD solar cell optimization. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Acceptor thickness effect of exciplex and electroplex emission at heterojunction interface in organic light-emitting diodes

Science.gov (United States)

Zhang, Wei; Yu, Junsheng; Yuan, Kai; Jiang, Yadong; Zhang, Qing; Cao, Kangli

2010-10-01

Organic light-emitting diodes (OLEDs) consisted of a novel fluorene derivative of 5,6-bis(9,9-dihexyl-9H-fluoren-2-yl)- 2,3-diisocyano-2,3-dihydropyrazine (BDHFLCNPy) and a hole transporting material of N,N'-Di-[(1-naphthalenyl)- N,N'-diphenyl](1,1'-biphenyl)-4,4'-diamine (NPB) were fabricated, and electroluminescence (EL) spectrum of devices were investigated. It was found that light emission around 650 nm observed in devices came from exciplex generated at heterojunction interface by NPB molecules worked as electron donor and BDHFLCNPy molecules worked as electron acceptor. Moreover, a shoulder peak around 500 nm ascribed to BDHFLCNPy exciton was observed. To systemically study the effect of heterojunction structure in exciplex formation, OLEDs with different thickness of acceptor were fabricated. The results illustrated that a shoulder peak around 600 nm occurred in EL when acceptor thickness increases, and BDHFLCNPy exciton emitting strength is relatively altered. The emission band around 600 nm is due to electroplex. The L-V-J properties of OLEDs show that device with the thinnest acceptor layer has the highest luminance and current density. On the contrary, OLEDs with thicker acceptor layer have higher luminance efficiency. The different recombination mechanism of exciton, exciplex and electroplex in heterojunction were studied. Furthermore, the acceptor thickness effect of exciplex and electroplex generating mechanism and energy transferring mechanism between them was also discussed.

Michael Pärt ئ suure muusika taustajõud / Michael Pärt ; interv. Siim Nestor

Index Scriptorium Estoniae

Pärt, Michael

2008-01-01

Arvo Pärdi pojast Michael Pärdist. Tema tööst "music editor"-ina - helimonteerijana, tööst muusika produktsiooni, salvestamise ja muusika kirjutamise abijõuna. Koostööst maailmas tuntud muusikutega

Efficiency-limiting processes in OPV bulk heterojunctions of GeNIDTBT and IDT-based acceptors

KAUST Repository

Al-Saggaf, Sarah M.

2018-01-01

to the ubiquitously used fullerene derivatives. NFAs showed a rapid increase in efficiencies, now exceeding a PCE of 13%. In my thesis research, I used two small molecule IDT-based acceptors, namely O-IDTBR and O-IDTBCN, in combination with a wide bandgap donor

Effects of 1 and 3 g cinnamon on gastric emptying, satiety, and postprandial blood glucose, insulin, glucose-dependent insulinotropic polypeptide, glucagon-like peptide 1, and ghrelin concentrations in healthy subjects

DEFF Research Database (Denmark)

Hlebowicz, Joanna; Hlebowicz, Anna; Lindstedt, Sandra

2009-01-01

glucose, plasma concentrations of insulin and incretin hormones [glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide 1 (GLP-1)], the ghrelin response, and satiety in healthy subjects. DESIGN: GER was measured by using real-time ultrasonography after ingestion of rice pudding...... with and without 1 or 3 g cinnamon. Fifteen healthy subjects were assessed in a crossover trial. RESULTS: The addition of 1 or 3 g cinnamon had no significant effect on GER, satiety, glucose, GIP, or the ghrelin response. The insulin response at 60 min and the area under the curve (AUC) at 120 min were...... cinnamon (P = 0.0082 and P = 0.0138, respectively, after Bonferroni correction). CONCLUSIONS: Ingestion of 3 g cinnamon reduced postprandial serum insulin and increased GLP-1 concentrations without significantly affecting blood glucose, GIP, the ghrelin concentration, satiety, or GER in healthy subjects...

The Effects of Chewing Cinnamon Flavored Gum on Mood, Feeling and Spelling Acquisition

Science.gov (United States)

Wilson, Andrew; Kim, Wonsun; Raudenbush, Bryan

2016-01-01

The purpose of the study is to investigate if the effects of chewing cinnamon flavored gum can increase mood, feeling and spelling acquisition. 5th grade students (n = 22) at Ilshin elementary school in South Korea served as participants. The same students were required to take 4 spelling tests with 1 given every day over the course of 4 days. For…

Intramolecular charge separation in spirobifluorene-based donor–acceptor compounds adsorbed on Au and indium tin oxide electrodes

International Nuclear Information System (INIS)

Heredia, Daniel; Otero, Luis; Gervaldo, Miguel; Fungo, Fernando; Dittrich, Thomas; Lin, Chih-Yen; Chi, Liang-Chen; Fang, Fu-Chuan; Wong, Ken-Tsung

2013-01-01

Surface photovoltage (SPV) measurements were performed with a Kelvin-probe in spirobifluorene-based donor (diphenylamine)–acceptor (dicyano or cyanoacrylic acid moieties) compounds adsorbed from highly diluted solutions onto Au and indium tin oxide electrode surfaces. Strong intramolecular charge separation (negative SPV signals up to more than 0.1 V) due to directed molecule adsorption was observed only for spirobifluorene donor–acceptor compounds with carboxylic acid moiety. SPV signals and onset energies of electronic transitions depended on ambience conditions. - Highlights: ► Fluorene donor–acceptor derivatives were adsorbed at Au and indium tin oxide. ► Surface photovoltage measurements were performed with a Kelvin-probe. ► Strong intra-molecular charge separation was observed. ► SPV signals depended on ambience conditions

Design, synthesis and photovoltaic properties of a series of new acceptor-pended conjugated polymers

Institute of Scientific and Technical Information of China (English)

Zhihong; Wu; Yongxiang; Zhu; Wei; Li; Yunping; Huang; Junwu; Chen; Chunhui; Duan; Fei; Huang; Yong; Cao

2016-01-01

A series of novel acceptor-pended conjugated polymers featuring a newly developed carbazole-derived unit are designed and synthesized. The relationships between chemical structure and optoelectronic properties of the polymers are systematically investigated.The control of UV-Vis absorption spectra and energy levels in resulting polymers are achieved by introducing suitable pended acceptor units. The photovoltaic properties of the resulting polymers are evaluated by blending the polymers with(6,6)-phenyl-C71-butyric acid methyl ester. The resulting solar cells exhibit moderate performances with high open-circuit voltage. Charge transport properties and morphology were investigated to understand the performance of corresponding solar cells.

Chiral Aminophosphines as Catalysts for Enantioselective Double-Michael Indoline Syntheses

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Ohyun Kwon

2012-05-01

Full Text Available The bisphosphine-catalyzed double-Michael addition of dinucleophiles to electron-deficient acetylenes is an efficient process for the synthesis of many nitrogen-containing heterocycles. Because the resulting heterocycles contain at least one stereogenic center, this double-Michael reaction would be even more useful if an asymmetric variant of the reaction were to be developed. Aminophosphines can also facilitate the double-Michael reaction and chiral amines are more readily available in Nature and synthetically; therefore, in this study we prepared several new chiral aminophosphines. When employed in the asymmetric double-Michael reaction between ortho-tosylamidophenyl malonate and 3-butyn-2-one, the chiral aminophosphines produced indolines in excellent yields with moderate asymmetric induction.

Effects of Cinnamon extract on biochemical enzymes, TNF-α and NF-κB gene expression levels in liver of broiler chickens inoculated with Escherichia coli

Directory of Open Access Journals (Sweden)

Seyed Mahmoud Tabatabaei

2015-09-01

Full Text Available Abstract: Infection with Escherichia coli (E. coli is a common disease in poultry industry. The use of antibiotics to treat diseases is facing serious criticism and concerns. The medicinal plants may be effective alternatives because of their multiplex activities. The aim of this study was to investigate the effects of cinnamon extract on the levels of liver enzymes, tumor necrosis factor-alpha (TNF-α and nuclear factor-kappa B (NF-κB gene expressions in liver of broiler chickens infected with E. coli. Ninety Ross-308 broilers were divided into healthy or E. coli-infected groups, receiving normal or cinnamon extract (in concentrations of 100 or 200mg/kg of food supplemented diets. E. coli suspension (108cfu was injected subcutaneously after 12 days cinnamon administration. Seventy-two hours after E. coli injection, the blood samples were taken for biochemical analysis of liver enzymes in serum (spectrophotometrically, and liver tissue samples were obtained for detection of gene expression of inflammatory markers TNF-α and NF-κB, using real-time PCR. Infection with E. coli significantly increased the levels of TNF-α and NF-κB gene expressions as well as some liver enzymes including creatine-kinase (CK, lactate-dehydrogenase (LDH, alanine-transferase (ALT and aspartate-transferase (AST as compared with control group (P<0.05. Pre-administration of cinnamon extract in broilers diet (in both concentrations significantly reduced the tissue levels of TNF-α and NF-κB gene expressions and enzymes CK and ALT in serum of broiler chickens inoculated with E. coli in comparison with E. coli group (P<0.05 and P<0.01. The levels of LDH and AST were significantly decreased only by 200mg/kg cinnamon extract in infected broilers. The level of alkaline-phosphatase (ALP was not affected in any groups. Pre-administration of cinnamon extract in diets of broiler chickens inoculated with E. coli could significantly reduce the gene expression levels of pro

Bark Extracts of Ceylon Cinnamon Possess Antilipidemic Activities and Bind Bile Acids In Vitro

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Walimuni Prabhashini Kaushalya Mendis Abeysekera

2017-01-01

Full Text Available Ethanol (95% and dichloromethane : methanol (1 : 1 bark extracts of authenticated Ceylon cinnamon were investigated for range of antilipidemic activities (ALA: HMG-CoA reductase, lipase, cholesterol esterase, and cholesterol micellization inhibitory activities and bile acids binding in vitro. Individual compounds in bark extracts were also evaluated. Bark extracts showed ALA in all the assays studied. The IC50 (μg/mL values ranged within 153.07±8.38–277.13±32.18, 297.57±11.78–301.09±4.05, 30.61±0.79–34.05±0.41, and 231.96±9.22–478.89±9.27, respectively, for HMG-CoA reductase, lipase, cholesterol esterase, and cholesterol micellization inhibitory activities. The bile acids binding (3 mg/mL for taurocholate, glycodeoxycholate, and chenodeoxycholate ranged within 19.74±0.31–20.22±0.31, 21.97±2.21–26.97±1.61, and 16.11±1.42–19.11±1.52%, respectively. The observed ALA were moderate compared to the reference drugs studied. Individual compounds in bark extracts ranged within 2.14±0.28–101.91±3.61 and 0.42±0.03–49.12±1.89 mg/g of extract. Cinnamaldehyde and gallic acid were the highest and the lowest among the tested compounds. The ethanol extract had highest quantity of individual compounds and ALA investigated. Properties observed indicate usefulness of Ceylon cinnamon bark in managing hyperlipidemia and obesity worldwide. Further, this study provides scientific evidence for the traditional claim that Ceylon cinnamon has antilipidemic activities.

Use of Essential Oils of Cinnamon, Lavender and Peppermint for Weed Control

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Enio Campiglia

Full Text Available The indiscriminate use of synthetic chemical compounds for weed control has been often responsible of damage to both the environment and the human health. To challenge these problems, in the last years research has increased its effort to find out alternative farming strategies. A feasible alternative could be the identification of natural substances with allelopathic effects for the realization of natural herbicides. Some research has already highlighted the possibility of using essential oils, extracted from aromatic plants, for weed control. The advantage in the utilization of such natural compounds is the quickly breaking down process into the environment and so the possible application in sustainable agriculture like organic farming. Objective of this research was the evaluation of the inhibition effect exerted by the essential oils of cinnamon, peppermint and lavender on seeds germination of some of the most common weeds species of the Mediterranean environment (pigweed, wild mustard and ryegrass. The results have highlighted a control in the weeds germination. Among the essential oils tested, cinnamon oil has exerted the highest inhibition effect compared with lavender and peppermint ones. The dicotyledonous species have been more susceptible compared with the monocotyledonous, even if it has been recorded only for redroot pigweed a dose able to inhibit totally the seed germination.

Cinnamon extract regulates glucose transporter and insulin-signaling gene expression in mouse adipocytes.

Science.gov (United States)

Cao, Heping; Graves, Donald J; Anderson, Richard A

2010-11-01

Cinnamon extracts (CE) are reported to have beneficial effects on people with normal and impaired glucose tolerance, the metabolic syndrome, type 2 diabetes, and insulin resistance. However, clinical results are controversial. Molecular characterization of CE effects is limited. This study investigated the effects of CE on gene expression in cultured mouse adipocytes. Water-soluble CE was prepared from ground cinnamon (Cinnamomum burmannii). Quantitative real-time PCR was used to investigate CE effects on the expression of genes coding for adipokines, glucose transporter (GLUT) family, and insulin-signaling components in mouse 3T3-L1 adipocytes. CE (100 μg/ml) increased GLUT1 mRNA levels 1.91±0.15, 4.39±0.78, and 6.98±2.18-fold of the control after 2-, 4-, and 16-h treatments, respectively. CE decreased the expression of further genes encoding insulin-signaling pathway proteins including GSK3B, IGF1R, IGF2R, and PIK3R1. This study indicates that CE regulates the expression of multiple genes in adipocytes and this regulation could contribute to the potential health benefits of CE. Published by Elsevier GmbH.

Michael Roitmann : Kalandus ei ole Eestile ilmselt prioriteetne valdkond / Michael Roitmann ; interv. Marko Saaret

Index Scriptorium Estoniae

Roitmann, Michael

2003-01-01

Ilmunud ka: Delovõje Vedomosti 3. dets. lk. 9. Euroopa Komisjoni kalandusdirektoraadi koordinaator Euroopa Liidu laienemise küsimuses Michael Roitmann juhib tähelepanu Eesti kalanduse suurematele probleemidele ning prognoosib EL-iga liitumise mõju Eesti kalandussektori arengule

Assessment of antibacterial effect of cinnamon on growth of porphyromons gingivalis from chronic periodontitis patients with deep pockets (in vitro

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Babak Amoian

2014-04-01

Full Text Available   Background and Aims : Antibiotics are commonly used for controlling the growth of porphyromons gingivalis (P.g which is one of the most important etiologic factors in the periodontal diseases. Different side effects of synthetics and chemical drugs such as increasing the drug resistancy in the human pathogens have led to study on the herbal antibacterial effect. The aim of this study was to evaluate the antibacterial effect of cinnamon on the growth of porphyromons gingivalis in chronic periodontitis patients with deep pockets.   Materials and Methods: In this experimental study, samples were provided from patients having pockets. After culturing the microorganism and diagnosis of P.g by gram staining and biochemical tests, cinnamon in different concentrations (10, 50, 100, 250, 500, 750 and 1500 mg/ml with oil solvent were prepared and placed by disks in the cultures medium. Positive controls were amoxicillin, metronidazole, ciprofloxacin, amikacin and gentamycin . Oil was negative control. Then the plates were incubated for 24 hours in 37 0 C and then non-growth halos by disk diffusion method, MIC (Minimum Inhibitory Concentration and MBC (Minimum Bactericidal Concentration were determined. Data were analyzed using One-way ANOVA test.   Results: The results showed that the cinnamon at the concentration of MIC=750 mg/ml had the inhibitory effects of bacteria and at the concentration of MIC=1500 mg/ml had killing effect. However, this antibacterial effect compared with commonly used antibiotics (amoxicillin, metronidazole, was much weaker (P<0.001.   Conclusion: Cinnamon showed an antimicrobial effect on porphyromonas gingivalis in chronic periodontitis patients with deep pockets.

Alkyl Radicals as Hydrogen Bond Acceptors: Computational Evidence

DEFF Research Database (Denmark)

Hammerum, Steen

2009-01-01

Spectroscopic, energetic and structural information obtained by DFT and G3-type computational studies demonstrates that charged proton donors can form moderately strong hydrogen bonds to simple alkyl radicals. The presence of these bonds stabilizes the adducts and modifies their structure......, and gives rise to pronounced shifts of IR stretching frequencies and to increased absorption intensities. The hydrogen bond acceptor properties of alkyl radicals equal those of many conventional acceptors, e.g., the bond length changes and IR red-shifts suggest that tert-butyl radicals are slightly better...... acceptors than formaldehyde molecules, while propyl radicals are as good as H2O. The hydrogen bond strength appears to depend on the proton affinity of the proton donor and on the ionization energy of the acceptor alkyl radical, not on the donor-acceptor proton affinity difference, reflecting...

Efficiency-limiting processes in OPV bulk heterojunctions of GeNIDTBT and IDT-based acceptors

KAUST Repository

Al-Saggaf, Sarah M.

2018-05-16

The successful realization of highly efficient bulk heterojunction OPV devices requires the development of organic donor and acceptor materials with tailored properties. Recently, non-fullerene acceptors (NFAs) have emerged as an alternative to the ubiquitously used fullerene derivatives. NFAs showed a rapid increase in efficiencies, now exceeding a PCE of 13%. In my thesis research, I used two small molecule IDT-based acceptors, namely O-IDTBR and O-IDTBCN, in combination with a wide bandgap donor polymer, GeNIDT-BT, as active material in BHJ solar cells and investigated their photophysical characteristics. The polymer combined with O-IDTBR as acceptor achieved a power conversion efficiency of only 2%, which is significantly lower than that obtained for the system of GeNIDT-BT: O-IDTBCN (5.3%). Using nano- to microsecond transient absorption spectroscopy, I investigated both systems and demonstrated that GeNIDT-BT:O-IDTBR exhibits more geminate recombination of interfacial charge-transfer states, leading to lower short circuit currents. Using time-delayed collection field experiments, I studied the field dependence of charge generation and its impact on the device fill factor. Overall, my results provide a qualitative understanding of the efficiency-limiting processes in both systems and their impact on device performance.

Effects of Cinnamon Consumption on Glycemic Indicators, Advanced Glycation End Products, and Antioxidant Status in Type 2 Diabetic Patients

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Behrouz Talaei

2017-09-01

Full Text Available The aim of the current study was to determine the effect of a daily intake of three grams of cinnamon over eight weeks on glycemic indicators, advanced glycation end products, and antioxidant status in patients with type 2 diabetes. In a double-blind, randomized, placebo controlled clinical trial study, 44 patients with type 2 diabetes, aged 57 ± 8 years, were randomly assigned to take either a three g/day cinnamon supplement (n = 22 or a placebo (n = 22 for eight weeks. We measured the fasting blood glucose, insulin, hemoglobinbA1c, homeostasis model assessment for insulin resistance (HOMA-IR, carboxymethyl lysine, total antioxidant capacity, and malondialdehyde levels at the beginning and the end of the study. Thirty-nine patients (20 in the intervention group and 19 in the control group completed the study. After an eight-week intervention, changes in the level of fasting blood glucose, insulin, hemoglobinbA1c, HOMA-IR, carboxymethyl lysine, total antioxidant capacity, and malondialdehyde were not significant in either group, nor were any significant differences between groups observed in these glycemic and inflammatory indicators at the end of the intervention. Our study revealed that cinnamon supplementation had no significant effects on glycemic and inflammatory indicators in patients with type 2 diabetes.

Book Review: Invitation to Topological Robotics by Michael Farber

DEFF Research Database (Denmark)

Raussen, Martin

2009-01-01

Book Review: Invitaton to Topological Robotics by Michael Farber. Zurich Lectures in Advanced Mathematics, European Mathematical Society (2008), ISBN 978-3-03719-054-8......Book Review: Invitaton to Topological Robotics by Michael Farber. Zurich Lectures in Advanced Mathematics, European Mathematical Society (2008), ISBN 978-3-03719-054-8...

Excessive application of pig manure increases the risk of P loss in calcic cinnamon soil in China.

Science.gov (United States)

Yang, Yanju; Zhang, Haipeng; Qian, Xiaoqing; Duan, Jiannan; Wang, Gailan

2017-12-31

Soil phosphorus (P) is a critical factor affecting crop yields and water environmental quality. To investigate the degree of loss risk and forms of soil P in calcic cinnamon soil, the P fraction activities in soils were analysed using chemical methods, combined with an in situ field experiment. Seven treatments were set in this study, including control (unfertilized), no P fertilizer (No-P), mineral P fertilizer (Min-P), low (L-Man) and high (H-Man) quantities of pig manure, Min-P+L-Man, and Min-P+H-Man. The results showed that manure fertilizer could not only significantly increase maize yield but could also enhance the accumulation of soil P in organic and inorganic forms. After 23years of repeated fertilization, the soil Olsen-P contents respectively showed 64.7-, 43.7- and 31.9-fold increases in the Min-P+H-Man, Min-P+L-Man and H-Man treatments, while the soil Olsen-P in Min-P treatment only increased 23.7-fold. The soil Olsen-P thresholds ranged from 22.59 to 32.48mgkg -1 in calcic cinnamon soil to maintain a higher maize yield as well as a lower risk of P loss. Therefore, long-term excessive manure application could obviously raise the content of soil Olsen-P and increase the risk of P loss in calcic cinnamon soil. Copyright © 2017 Elsevier B.V. All rights reserved.

Effects of cinnamon consumption on glycemic status, lipid profile and body composition in type 2 diabetic patients.

Science.gov (United States)

Vafa, Mohammadreza; Mohammadi, Farhad; Shidfar, Farzad; Sormaghi, Mohammadhossein Salehi; Heidari, Iraj; Golestan, Banafshe; Amiri, Fatemehsadat

2012-08-01

Type 2 diabetes is the most common metabolic disorder worldwide. Traditional herbs and spices can be used to control blood glucose concentrations. The objective of this study was to evaluate the effects of the daily intake of three grams cinnamon over eight weeks on glycemic status, lipid profiles and body composition in type 2 diabetic patients. A double blind, randomized, placebo controlled clinical trial was conducted on 44 patients with type 2 diabetes. Participants were randomly assigned to take either a three g/day cinnamon supplement (n=22) or a placebo (n=22) for eight weeks. Weight, height, body fat mass and systolic and diastolic blood pressure were measured at baseline and after intervention. The fasting blood glucose, insulin, HbA1c, total cholesterol, LDL C, HDL C, Apo lipoprotein A I and B were measured at baseline and endpoint. From 44 subjects participated in this study 37 completed the study. There were no significant differences in baseline characteristics, dietary intake and physical activity between groups. In the treatment group, the levels of fasting blood glucose, HbA1c, triglyceride, weight, BMI and body fat mass decreased significantly compared to baseline, but not in placebo group. No significant differences were observed in glycemic status indicators, lipid profile and anthropometric indicators between the groups at the end of intervention. These data suggest that cinnamon may have a moderate effect in improving glycemic status indicators.

Novel indole-based inhibitors of IMPDH: introduction of hydrogen bond acceptors at indole C-3.

Science.gov (United States)

Watterson, Scott H; Dhar, T G Murali; Ballentine, Shelley K; Shen, Zhongqi; Barrish, Joel C; Cheney, Daniel; Fleener, Catherine A; Rouleau, Katherine A; Townsend, Robert; Hollenbaugh, Diane L; Iwanowicz, Edwin J

2003-04-07

The development of a series of novel indole-based inhibitors of 5'-inosine monophosphate dehydrogenase (IMPDH) is described. Various hydrogen bond acceptors at C-3 of the indole were explored. The synthesis and the structure-activity relationships (SARs) derived from in vitro studies are outlined.

The Effect of Four-Week Period of Aerobic Exercise with Cinnamon Consumption on Lipoprotein Indicates and Blood sugar in Diabetic Female Patients (Type 2

Directory of Open Access Journals (Sweden)

M Dastani

2013-01-01

Full Text Available Introduction: Cinnamon as an herbal medicine has the ability to reduce blood glucose and lipoproteins in diabetic patients. Based on the positive effects of exercise on diabetic patients, the present study was conducted to investigate the effect of Four weeks Period aerobic exercise alongside using cinnamon on lipoprotein parameters and blood glucose in women with type 2 diabetes. Methods: Thirty diabetic women were voluntarily selected and were randomly divided into three groups: 1 aerobic exercise group; 2 aerobic exercise alongside using cinnamon; and 3 control group. Aerobic exercise took four weeks with 60 percent of maximum heart rate. Blood samples were collected at the beginning and end of the study. Results: Blood glucose, the fat percentage and HDL, and the ratio of LDL to HDL in the first group significantly decreased and in the second group increased (P<0.05. Also the first group showed a significant reduction in triglyceride. The only significant change observed in the control group was a significant increase in the level of LDL. Comparing the first and second group, it was observed that in the second group the level of total cholesterol decreased and the ratio of LDL to HDL increased (P<0.05. Conclusion: Using cinnamon alongside aerobic exercise is likely to be beneficial in regulating the concentration of blood glucose and lipids in diabetic patients.

Michael Faraday vs. the Spiritualists

Science.gov (United States)

Hirshfeld, Alan

2006-12-01

In the 1850s, renowned physicist Michael Faraday launched a public campaign against pseudoscience and spiritualism, which were rampant in England at the time. Faraday objected especially to claims that electrical or magnetic forces were responsible for paranormal phenomena, such as table-spinning and communication with the dead. Using scientific methods, Faraday unmasked the deceptions of spiritualists, clairvoyants and mediums and also laid bare the credulity of a public ill-educated in science. Despite his efforts, Victorian society's fascination with the paranormal swelled. Faraday's debacle anticipates current controversies about public science education and the interface between science and religion. This episode is one of many described in the new biography, The Electric Life of Michael Faraday (Walker & Co.), which chronicles Faraday's discoveries and his unlikely rise from poverty to the pinnacle of the English science establishment.

In vitro antimicrobial activities of cinnamon bark oil, anethole, carvacrol, eugenol and guaiazulene against Mycoplasma hominis clinical isolates.

Science.gov (United States)

Sleha, Radek; Mosio, Petra; Vydrzalova, Marketa; Jantovska, Alexandra; Bostikova, Vanda; Mazurova, Jaroslava

2014-06-01

The aim of this study was to evaluate the antimicrobial effects of five natural substances against 50 clinical isolates of Mycoplasma hominis. The in vitro activity of selected natural compounds, cinnamon bark oil, anethole, carvacrol, eugenol and guaiazulene, was investigated against 50 M. hominis isolates cultivated from cervical swabs by the broth dilution method. All showed valuable antimicrobial activity against the tested isolates. Oil from the bark of Cinnamomum zeylanicum (MBC90 = 500 µg/mL) however was found to be the most effective. Carvacrol (MBC90 = 600 µg/mL) and eugenol (MBC90 = 1000 µg/mL) also possessed strong antimycoplasmal activity. The results indicate that cinnamon bark oil, carvacrol and eugenol have strong antimycoplasmal activity and the potential for use as antimicrobial agents in the treatment of mycoplasmal infections.

Barbiturate End-Capped Non-Fullerene Acceptors for Organic Solar Cells: Tuning Acceptor Energetics to Suppress Geminate Recombination Losses

KAUST Repository

Tan, Ching-Hong

2018-01-10

We report the synthesis of two barbiturate end-capped non-fullerene acceptors and demonstrate their efficient function in high voltage output organic solar cells. The acceptor with the lower LUMO level is shown to exhibit suppressed geminate recombination losses, resulting in enhanced photocurrent generation and higher overall device efficiency.

Barbiturate End-Capped Non-Fullerene Acceptors for Organic Solar Cells: Tuning Acceptor Energetics to Suppress Geminate Recombination Losses

KAUST Repository

Tan, Ching-Hong; Gorman, Jeffrey; Wadsworth, Andrew; Holliday, Sarah; Subramaniyan, Selvam; Jenekhe, Samson A.; Baran, Derya; McCulloch, Iain; Durrant, James

2018-01-01

We report the synthesis of two barbiturate end-capped non-fullerene acceptors and demonstrate their efficient function in high voltage output organic solar cells. The acceptor with the lower LUMO level is shown to exhibit suppressed geminate recombination losses, resulting in enhanced photocurrent generation and higher overall device efficiency.

Production of Low-Freezing-Point Highly Branched Alkanes through Michael Addition.

Science.gov (United States)

Jing, Yaxuan; Xia, Qineng; Liu, Xiaohui; Wang, Yanqin

2017-12-22

A new approach for the production of low-freezing-point, high-quality fuels from lignocellulose-derived molecules was developed with Michael addition as the key step. Among the investigated catalysts, CoCl 2 ⋅6 H 2 O was found most active for the Michael addition of 2,4-pentanedione with FA (single aldol adduct of furfural and acetone, 4-(2-furanyl)-3-butene-2-one). Over CoCl 2 ⋅6 H 2 O, a high carbon yield of C 13 oxygenates (about 75 %) can be achieved under mild conditions (353 K, 20 h). After hydrodeoxygenation, low-freezing-point (hydrodeoxygenation, high density (0.8415 g mL -1 ) and low-freezing-point (<223 K) branched alkanes with 18, 23 carbons within lubricant range were also obtained over a Pd/NbOPO 4 catalyst. These highly branched alkanes can be directly used as transportation fuels or additives. This work opens a new strategy for the synthesis of highly branched alkanes with low freezing point from renewable biomass. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Synthesis and Characterization of C-Cinnamal Calix [4] Resorsinarena from Cinnamon Oil Waste West Sumatra

Science.gov (United States)

Etika, S. B.; Nasra, E.; Rilaztika, I.

2018-04-01

Synthesis and characterization of compound C-Cinnamal Calix [4] Resorsinarena (CCCR) of cinnamon oil waste have been done. This study was aimed to synthesis and characterize C-Cinnamal Calix [4] Resorsinarena from cinnamaldehyde violated cinnamon oil waste. C-Cinnamal Calix [4] Resorsinarena was synthesized by electrophilic substitution reaction of cinnamaldehyde isolated by the acid and resorcinol at 77oC temperature for 2 hour. The data analysis spectrum UV-VIS and FT-IR showed that the compound isolated cinnamaldehyde same as pure cinnamaldehyde compound. The characterization of C-Cinnamal Calix [4] Resorsinarena in the form of reddish-colored solids with melting point 3580C by using UV-VIS showed the presence of double bond, FT-IR showed the absorption at the wave number 3323,94 cm-1 indicating the ‑OH group, the wave number 1610,94 cm-1 showed the vibration C=C, the strong region absorption of 1500,86 cm-1 indicating the presence of an aromatic ring, the at 1442,88 cm-1 wave number indicating the presence of CH3.

Optical and structure characterization of cinnamon nanoparticles synthesized by pulse laser ablation in liquid (PLAL)

Science.gov (United States)

Aqeel Salim, Ali; Bidin, Noriah; Bakhtiar, Hazri; Krishna Ghoshal, Sib; Azawi, Mohammed Al; Krishnan, Ganesan

2018-05-01

Organic nanoparticles development is under exploration due to its beneficial applications in nanobiomedical and research interests. PLAL technique of Q-switched 1064-Nd: YAG (10 ns pulse duration, repetition rate 1 Hz and laser energy 20-100 mJ) has inherent advantages and rapid growth of nanoparticles when compared to conventional methods because of the controlled fabricated nanoparticles, stability, and purity. Cinnamon sticks as a target are immersed in 5 ml ethanol medium and irradiated by a laser beam for the growth process. The morphology, optical characteristic, and bonding structure of cinnamon nanoparticles (CNPs) are determined and evaluated by transmission electron microscope (TEM), UV-Visible spectroscopy and Fourier transform infrared spectroscopy (FTIR). Spherical, homogenous and high crystallinity CNPs was revealed within the particle size range of 2 - 28 nm. The absorption band was found in the ultraviolent region around 259 nm and 319 nm. The present of FTIR spectra confirmed that the nanoparticles were covered by plant secondary metabolites. The experimental findings revealed that the synthesize CNPs in ethanol has a potential for nanomedicine applications.

Asymmetric Domino Aza-Michael Addition/[3+2] Cycloaddition Reactions as a Versatile Approach to alpha,beta,gamma,-Triamino Acid Derivatives

Czech Academy of Sciences Publication Activity Database

Kapras, Vojtěch; Pohl, Radek; Císařová, I.; Jahn, Ullrich

2014-01-01

Roč. 16, č. 4 (2014), s. 1088-1091 ISSN 1523-7060 Institutional support: RVO:61388963 Keywords : 1,3-dipolar cycloaddition * lithium amides * aza-Michael addition * amino acids * pyrazoles Subject RIV: CC - Organic Chemistry Impact factor: 6.364, year: 2014

Some pharmacological effects of cinnamon and ginger herbs in obese diabetic rats

OpenAIRE

Shalaby, Mostafa Abbas; Saifan, Hamed Yahya

2014-01-01

Aims: The present study was designed to assess some pharmacological effects of cinnamon (CAE) and ginger (GAE) aqueous extracts in obese diabetic rats, and to elucidate the potential mechanisms. Materials and Methods: Forty-two Sprague-Dawley rats were randomized into 6 equal groups. Group 1 was a negative control and the other groups were rendered obese by feeding rats on high-fat diet for 4 weeks. The obese rats were subcutaneously injected with alloxan for 5*days to induce diabetes. Group ...

Michael Tomasello: Award for Distinguished Scientific Contributions.

Science.gov (United States)

2015-11-01

The APA Awards for Distinguished Scientific Contributions are presented to persons who, in the opinion of the Committee on Scientific Awards, have made distinguished theoretical or empirical contributions to basic research in psychology. One of the 2015 award winners is Michael Tomasello, who received this award for "outstanding empirical and theoretical contributions to understanding what makes the human mind unique. Michael Tomasello's pioneering research on the origins of social cognition has led to revolutionary insights in both developmental psychology and primate cognition." Tomasello's award citation, biography, and a selected bibliography are presented here. (c) 2015 APA, all rights reserved).

Effect Of Using Ginger And / Or Cinnamon, As An Irradiated Supplement, On Lipid Profiles And Antioxidant Activities Of Dietary-Induced Hypercholesterolemia In Rats

International Nuclear Information System (INIS)

Farag, M.F.S.; Osman, N.N.; Yonies, B.M.

2007-01-01

Combating hypercholesterolemia is one of the modern nutrition directions. Towards this goal, hypercholesterolemia diet (HCD) containing cholesterol (1% w/w) and sodium cholate (0.2% w/w) was investigated on male Wister rats. Ginger and/or cinnamon (1% w/w) irradiated with 10 KGy were added to the HCD as a decontaminated supplement to evaluate the efficacy of these spices in reducing hypercholesterolemia. Their effects on serum and hepatic lipid, atherogenic index, blood and liver lipid peroxidation and antioxidant properties were determined. It was found that, the use of either ginger or cinnamon or both reduced TG, TC and LDL-C and increased HDL-C. Also, these spices suppressed lipid peroxidation via enhancement of antioxidant activities. The mixture of the two spices was more effective on the studied parameters in HCD fed rats. Thus, it could be concluded that intake of ginger and cinnamon may minimize the risk of atherosclerosis associated with a high cholesterol diet. These overall results support the future use of these spices and that continuous spices intake may be recommended in human

Following Michael Faraday's Footprints

Science.gov (United States)

Galeano, Javier

2011-01-01

Last fall I had the good fortune of receiving financial support to shoot a documentary about Michael Faraday. I took the opportunity to learn more about this great experimentalist and to visit the highlights of places in his life. In this paper, I would like to share a list and description of some of the most remarkable places in London suitable…

Development of Polymer Acceptors for Organic Photovoltaic Cells

Directory of Open Access Journals (Sweden)

Yujeong Kim

2014-02-01

Full Text Available This review provides a current status report of the various n-type polymer acceptors for use as active materials in organic photovoltaic cells (OPVs. The polymer acceptors are divided into four categories. The first section of this review focuses on rylene diimide-based polymers, including perylene diimide, naphthalene diimide, and dithienocoronene diimide-based polymers. The high electron mobility and good stability of rylene diimides make them suitable for use as polymer acceptors in OPVs. The second section deals with fluorene and benzothiadiazole-based polymers such as poly(9,9’-dioctylfluorene-co-benzothiadiazole, and the ensuing section focuses on the cyano-substituted polymer acceptors. Cyano-poly(phenylenevinylene and poly(3-cyano-4-hexylthiophene have been used as acceptors in OPVs and exhibit high electron affinity arising from the electron-withdrawing cyano groups in the vinylene group of poly(phenylenevinylene or the thiophene ring of polythiophene. Lastly, a number of other electron-deficient groups such as thiazole, diketopyrrolopyrrole, and oxadiazole have also been introduced onto polymer backbones to induce n-type characteristics in the polymer. Since the first report on all-polymer solar cells in 1995, the best power conversion efficiency obtained with these devices to date has been 3.45%. The overall trend in the development of n-type polymer acceptors is presented in this review.

Effects of Cinnamon, Cardamom, Saffron, and Ginger Consumption on Markers of Glycemic Control, Lipid Profile, Oxidative Stress, and Inflammation in Type 2 Diabetes Patients.

Science.gov (United States)

Azimi, Paria; Ghiasvand, Reza; Feizi, Awat; Hariri, Mitra; Abbasi, Behnoud

2014-01-01

Type 2 diabetes (T2D) may be caused by elevated oxidative stress, inflammation, and hyperglycemia. The phytochemicals in several herbal medicines are reported to effectively improve diabetes and to ameliorate diabetic complications. The aim of the present study was to determine the effects of cinnamon, cardamom, saffron, and ginger as supplementary remedies in T2D. This randomized controlled, clinical trial included 204 T2D patients. The participants were randomly assigned to four intervention groups receiving 3 glasses of black tea and either 3 g cardamom, or cinnamon, or ginger, or 1 g saffron and one control group which consumed only 3 tea glasses without any herbal medicine for 8 weeks. Markers of inflammation, oxidative stress, fasting blood sugar, lipid profile, and anthropometric measures were evaluated at baseline and after 8 weeks of intervention. After 8 weeks of intervention, cinnamon, cardamom, ginger, and saffron consumption had significant effects on total cholesterol, LDL, and HDL levels (p < 0.05) compared with controls. However, the herbal products did not have significant effects on measures of glycemic control, anthropometry, inflammation, and oxidative stress. In within-group comparisons only, cinnamon intake significantly decreased fasting blood sugar (FBS). The herbal remedies examined had significantly beneficial effects on cholesterol, but not on measures of glycemic control, oxidative stress, and inflammation. Based on the contradictory results reported in the literature, the effects of herbal medicine in diabetic patients should undergo further detailed investigation.

Comparing the Device Physics and Morphology of Polymer Solar Cells Employing Fullerenes and Non-Fullerene Acceptors

KAUST Repository

Bloking, Jason T.

2014-04-23

There is a need to find electron acceptors for organic photovoltaics that are not based on fullerene derivatives since fullerenes have a small band gap that limits the open-circuit voltage (VOC), do not absorb strongly and are expensive. Here, a phenylimide-based acceptor molecule, 4,7-bis(4-(N-hexyl-phthalimide)vinyl)benzo[c]1,2,5-thiadiazole (HPI-BT), that can be used to make solar cells with VOC values up to 1.11 V and power conversion efficiencies up to 3.7% with two thiophene polymers is demonstrated. An internal quantum efficiency of 56%, compared to 75-90% for polymer-fullerene devices, results from less efficient separation of geminate charge pairs. While favorable energetic offsets in the polymer-fullerene devices due to the formation of a disordered mixed phase are thought to improve charge separation, the low miscibility (<5 wt%) of HPI-BT in polymers is hypothesized to prevent the mixed phase and energetic offsets from forming, thus reducing the driving force for charges to separate into the pure donor and acceptor phases where they can be collected. A small molecule electron acceptor, 4,7-bis(4-(N-hexyl-phthalimide)vinyl)benzo[c]1,2,5-thiadiazole (HPI-BT), achieves efficiencies of 3.7% and open-circuit voltage values of 1.11 V in bulk heterojunction (BHJ) devices with polythiophene donor materials. The lower internal quantum efficiency (56%) in these non-fullerene acceptor devices is attributed to an absence of the favorable energetic offsets resulting from nanoscale mixing of donor and acceptor found in comparable fullerene-based devices. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Effects of Dietary Inclusion of Turmeric (Curcuma longa and Cinnamon (Cinnamomum verum Powders on Performance, Organs Relative Weight and Some Immune System Parameters in Broiler Chickens

Directory of Open Access Journals (Sweden)

Naderi M

2014-12-01

Full Text Available A total of 240 Ross 308 day-old male broiler chicks within a completely randomized design were used in this experiment to evaluate the effects of dietary inclusion of turmeric powder and cinnamon powder on performance and some immune responses of broiler chickens. Dietary treatments were as follow: a corn-soybean meal basal diet (control; basal diet + 10 ppm avilamycin; basal diet + 2.5 g/Kg turmeric powder; basal diet + 7.5 g/Kg turmeric powder; basal diet + 2.5 g/Kg cinnamon powder; and basal diet + 7.5 g/Kg cinnamon powder. During the experiment, feed intake, body weight gain, and feed conversion ratio were measured in the beginning and the end of starter (0-21 d. and grower (22-42 d. periods. On 21 d. of age, two chicks from each replicate were randomly selected and blood samples were taken. Differential enumeration of heterophils, lymphocytes, and monocytes were done. Also, antibody titers against IBV, IBD, and NDV vaccines were measured. Addition of 2.5 g/Kg turmeric powder increased body weight gain in the starter period and improved feed conversion ratio in the starter and entire periods of the experiment, when compared to the control (P. Also, inclusion of 10 ppm avilamycin into diet improved feed conversion ratio in the grower and entire periods of the experiment, comparing to the control (P. Inclusion of turmeric powder at 2.5 g/Kg or 7.5 g/Kg and cinnamon powder at 7.5 g/Kg declined the heterophil to lymphocyte ratio (P. The results of this study showed that turmeric powder at the level of 2.5 g/Kg would be a potential alternative for antibiotic growth promoters. Also, reducing heterophil to lymphocyte ratio by turmeric and cinnamon powders, introduce them as potential stress alleviators in broiler chickens.

Synthesis and photovoltaic properties from inverted geometry cells and roll-to-roll coated large area cells from dithienopyrrole-based donor-acceptor polymers

DEFF Research Database (Denmark)

Yue, Wei; Larsen-Olsen, Thue Trofod; Hu, Xiaolian

2013-01-01

A series of donor-acceptor low band gap polymers composed of alternating dithienopyrrole or its derivative as donors and phthalimide or thieno[3,4-c]pyrrole-4,6-dione as acceptors (P1-P4) are synthesized by Stille coupling polymerization. All polymers show strong absorption in the visible region......, for P2 and P4 possessing thieno[3,4-c]pyrrole-4,6-dione as an acceptor, their film absorption covers the region of 500-800 nm and 500-750 nm respectively, which makes them attractive as low band gap polymer solar cell (PSC) materials. With the incorporation of thiophene bridges, P3 and P4 have 0...

Click and chemically triggered declick reactions through reversible amine and thiol coupling via a conjugate acceptor

Science.gov (United States)

Diehl, Katharine L.; Kolesnichenko, Igor V.; Robotham, Scott A.; Bachman, J. Logan; Zhong, Ye; Brodbelt, Jennifer S.; Anslyn, Eric V.

2016-10-01

The coupling and decoupling of molecular units is a fundamental undertaking of organic chemistry. Herein we report the use of a very simple conjugate acceptor, derived from Meldrum's acid, for the sequential ‘clicking’ together of an amine and a thiol in aqueous conditions at neutral pH. Subsequently, this linkage can be ‘declicked’ by a chemical trigger to release the original amine and thiol undisturbed. The reactivity differs from that of other crosslinking agents because the selectivity for sequential functionalization derives from an altering of the electrophilicity of the conjugate acceptor on the addition of the amine. We describe the use of the procedure to modify proteins, create multicomponent libraries and synthesize oligomers, all of which can be declicked to their starting components in a controlled fashion when desired. Owing to the mild reaction conditions and ease of use in a variety of applications, the method is predicted to have wide utility.

Phosphorus acceptor doped ZnO nanowires prepared by pulsed-laser deposition

International Nuclear Information System (INIS)

Cao, B Q; Lorenz, M; Rahm, A; Wenckstern, H von; Czekalla, C; Lenzner, J; Benndorf, G; Grundmann, M

2007-01-01

Phosphorus-doped ZnO (ZnO:P) nanowires were successfully prepared by a novel high-pressure pulsed-laser deposition process using phosphorus pentoxide as the dopant source. Detailed cathodoluminescence studies of single ZnO:P nanowires revealed characteristic phosphorus acceptor-related peaks: neutral acceptor-bound exciton emission (A 0 , X, 3.356 eV), free-to-neutral-acceptor emission (e, A 0 , 3.314 eV), and donor-to-acceptor pair emission (DAP, ∼3.24 and ∼3.04 eV). This means that stable acceptor levels with a binding energy of about 122 meV have been induced in the nanowires by phosphorus doping. Moreover, the induced acceptors are distributed homogeneously along the doped nanowires

A study of acceptors and non-acceptors of family planning methods among three tribal communities.

Science.gov (United States)

Mutharayappa, R

1995-03-01

Primary data were collected from 399 currently married women of the Marati, Malekudiya, and Koraga tribes in the Dakshina Kannada district of Karnataka State in this study of the implementation of family planning programs in tribal areas. The Marati, Malekudiya, and Koraga tribes are three different endogamous tribal populations living in similar ecological conditions. Higher levels of literacy and a high rate of acceptance of family planning methods, however, have been observed among these tribes compared to the rest of the tribal population in the state. 46.4% of currently married women aged 15-49 years in the tribes were acceptors of family planning methods, having a mean 3.7 children. The majority of acceptors opted for tubectomy and vasectomy. The adoption of spacing methods is less common among tribal people. Most acceptors received their operations through government health facilities. They were motivated mainly by female health workers and received both cash and other incentives to accept family planning. The main reason for non-acceptance of family planning among non-acceptors was the desire to conceive and bear more children. The data indicate that most of the tribal households are nuclear families with household size more or less similar to that of the general population. They have a higher literacy rate than the rest of the tribal population in the state, with literacy levels between males and females and between the three tribes being quite different; the school enrollment ratio is relatively higher for both boys and girls.

Obituary: Michael James Ledlow, 1964-2004

Science.gov (United States)

Puxley, Philip John; Grashuis, Randon M.

2004-12-01

Michael James Ledlow died on 5 June 2004 from a large, unsuspected brain tumor. Since 2000 he had been on the scientific staff of the Gemini Observatory in La Serena, Chile, initially as a Science Fellow and then as a tenure-track astronomer. Michael was born in Bartlesville, Oklahoma on 1 October 1964 to Jerry and Sharon Ledlow. He obtained his Bachelor Degree in astrophysics at the University of Oklahoma in 1987 and attended the University of New Mexico for his graduate work, obtaining his PhD while studying Galaxy Clusters under Frazer Owen in 1994. From 1995-1997 Michael held a postdoctoral position with Jack Burns at New Mexico State University where he used various astronomical facilities including the VLA and Apache Point Observatory to study distant galaxies. From 1998-2000 Michael rejoined the Physics and Astronomy Department at the University of New Mexico where he was a visiting professor until he moved on to Gemini. At the Gemini Observatory, Mike shared in the excitement, hard work and many long days and nights associated with bringing on-line a major new astronomical facility and its instrumentation. Following its commissioning he assisted visiting observers, supported and took data for many more remote users via the queue system, and for each he showed the same care and attention to detail evident in his own research to ensure that all got the best possible data. His research concentrated on the radio and optical properties of galaxy clusters, especially rich Abell clusters such as A2125, on luminous radio galaxies, including the detection of a powerful double radio source in the "wrong sort of galaxy," the spiral system 0313-192, and on EROs (extremely red objects), dusty galaxies barely detectable at optical wavelengths. Michael thoroughly enjoyed living in Chile and enthusiastically immersed himself in the culture of his surroundings. He and his family were actively involved with the International English Spanish Association in La Serena. He had a

Cinnamon from the selection of traditional applications to its novel effects on the inhibition of angiogenesis in cancer cells and prevention of Alzheimer's disease, and a series of functions such as antioxidant, anticholesterol, antidiabetes, antibacterial, antifungal, nematicidal, acaracidal, and repellent activities

Directory of Open Access Journals (Sweden)

Rafie Hamidpour

2015-04-01

Full Text Available The purpose of this article is to use search engines such as PubMed and Scifinder to locate scholarly articles and reports pertaining to Cinnamon (肉桂 ròu guì, its novel effects, preparation, analysis, and use in the prevention and treatment of serious illnesses, such as diabetes, cardiovascular diseases, Alzheimer’s disease, and cancer. Cinnamon has been used traditionally in food preparations and as an herbal medicine to treat a variety of ailments and their symptoms. Cinnamon is known to have antioxidant, antibacterial, anti-inflammatory, and other therapeutic properties. New studies reaffirm the importance of cinnamon as a spice but also suggest that it may be a natural remedy to treat serious diseases such as type 2 diabetes, chronic digestion problems, cardiovascular diseases, and even cancer and Alzheimer’s disease. This article presents a comprehensive analysis of the botanical, chemical, and pharmacological aspects of cinnamon.

Interview with Michael Apple: The Biography of a Public Intellectual

Science.gov (United States)

Peters, Michael A.

2015-01-01

Michael W. Apple is the John Bascom Professor of Curriculum and Instruction and Educational Policy Studies in the Departments of Curriculum and Instruction (CI) and Educational Policy Studies (EPS) at the University of Wisconsin-Madison School of Education where he has taught since 1970. Michael Apple is one of the foremost educational theorists…

Michael Beitz: Objects of Communication

Science.gov (United States)

Hoefferle, Mary

2014-01-01

For this Instructional Resource, the author interviewed contemporary sculptor Michael Beitz, who uses art to explore the role of designed objects in human communication and emotional experience. This column was written in response to calls for using Enduring Understandings/Big Ideas (National Coalition for Core Arts Standards, 2013; Stewart &…

Preservation Effect of Two-Stage Cinnamon Bark (Cinnamomum Burmanii) Oleoresin Microcapsules On Vacuum-Packed Ground Beef During Refrigerated Storage

Science.gov (United States)

Irfiana, D.; Utami, R.; Khasanah, L. U.; Manuhara, G. J.

2017-04-01

The purpose of this study was to determine the effect of two stage cinnamon bark oleoresin microcapsules (0%, 0.5% and 1%) on the TPC (Total Plate Count), TBA (thiobarbituric acid), pH, and RGB color (Red, Green, and Blue) of vacuum-packed ground beef during refrigerated storage (at 0, 4, 8, 12, and 16 days). This study showed that the addition of two stage cinnamon bark oleoresin microcapsules affected the quality of vacuum-packed ground beef during 16 days of refrigerated storage. The results showed that the TPC value of the vacuum-packed ground beef sample with the addition 0.5% and 1% microcapsules was lower than the value of control sample. The TPC value of the control sample, sample with additional 0.5% and 1% microcapsules were 5.94; 5.46; and 5.16 log CFU/g respectively. The TBA value of vacuum-packed ground beef were 0.055; 0.041; and 0.044 mg malonaldehyde/kg, resepectively on the 16th day of storage. The addition of two-stage cinnamon bark oleoresin microcapsules could inhibit the growth of microbia and decrease the oxidation process of vacuum-packed ground beef. Moreover, the change of vacuum-packed ground beef pH and RGB color with the addition 0.5% and 1% microcapsules were less than those of the control sample. The addition of 1% microcapsules showed the best effect in preserving the vacuum-packed ground beef.

Wide-range light-harvesting donor-acceptor assemblies through specific intergelator interactions via self-assembly.

Science.gov (United States)

Samanta, Suman K; Bhattacharya, Santanu

2012-12-03

We have synthesized two new low-molecular-mass organogelators based on tri-p-phenylene vinylene derivatives, one of which could be designated as the donor whereas the other one is an acceptor. These were prepared specifically to show the intergelator interactions at the molecular level by using donor-acceptor self-assembly to achieve appropriate control over their macroscopic properties. Intermolecular hydrogen-bonding, π-stacking, and van der Waals interactions operate for both the individual components and the mixtures, leading to the formation of gels in the chosen organic solvents. Evidence for intergelator interactions was acquired from various spectroscopic, microscopic, thermal, and mechanical investigations. Due to the photochromic nature of these molecules, interesting photophysical properties, such as solvatochromism and J-type aggregation, were clearly observed. An efficient energy transfer was exhibited by the mixture of donor-acceptor assemblies. An array of four chromophores was built up by inclusion of two known dyes (anthracene and rhodamine 6G) for the energy-transfer studies. Interestingly, an energy-transfer cascade was observed in the assembly of four chromophores in a particular order (anthracene-donor-acceptor-rhodamine 6G), and if one of the components was removed from the assembly the energy transfer process was discontinued. This allowed the build up of a light-harvesting process with a wide range. Excitation at one end produces an emission at the other end of the assembly. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Michael Faraday, media man.

Science.gov (United States)

Fara, Patricia

2006-03-01

Michael Faraday was an enthusiastic portrait collector, and he welcomed the invention of photography not only as a possible means of recording observations accurately, but also as a method for advertising science and its practitioners. This article (which is part of the Science in the Industrial Revolution series) shows that like many eminent scientists, Faraday took advantage of the burgeoning Victorian media industry by posing in various roles.

Alternansucrase acceptor reactions with D-tagatose and L-glucose.

Science.gov (United States)

Côté, Gregory L; Dunlap, Christopher A; Appell, Michael; Momany, Frank A

2005-02-07

Alternansucrase (EC 2.4.1.140) is a d-glucansucrase that synthesizes an alternating alpha-(1-->3), (1-->6)-linked d-glucan from sucrose. It also synthesizes oligosaccharides via d-glucopyranosyl transfer to various acceptor sugars. Two of the more efficient monosaccharide acceptors are D-tagatose and L-glucose. In the presence of d-tagatose, alternansucrase produced the disaccharide alpha-d-glucopyranosyl-(1-->1)-beta-D-tagatopyranose via glucosyl transfer. This disaccharide is analogous to trehalulose. We were unable to isolate a disaccharide product from L-glucose, but the trisaccharide alpha-D-glucopyranosyl-(1-->6)-alpha-d-glucopyranosyl-(1-->4)-l-glucose was isolated and identified. This is analogous to panose, one of the structural units of pullulan, in which the reducing-end D-glucose residue has been replaced by its L-enantiomer. The putative L-glucose disaccharide product, produced by glucoamylase hydrolysis of the trisaccharide, was found to be an acceptor for alternansucrase. The disaccharide, alpha-D-glucopyranosyl-(1-->4)-L-glucose, was a better acceptor than maltose, previously the best known acceptor for alternansucrase. A structure comparison of alpha-D-glucopyranosyl-(1-->4)-L-glucose and maltose was performed through computer modeling to identify common features, which may be important in acceptor affinity by alternansucrase.

En bog om Michael Strunge

DEFF Research Database (Denmark)

Mai, Anne-Marie

Antologi med bidrag om Michael Strunges forfatterskab. Bidrag af Anne-Marie Mai, Jørgen Aabenhus, Marianne Stidsen, Moritz Schramm, Tue Andersen Nexø, Lars Bukdahl, Jon Helt Haarder, Rune Kühl er optaget efter fagfællesbedømmelse. Antologien er redigeret af Anne-Marie Mai og Jørgen Aabenhus....

Comparison of acceptor properties for interaction of TCNE and DDQ ...

African Journals Online (AJOL)

... with tetracyanoethylene and 2,3-dichloro-5,6-dicyanobezoquinone as acceptors result in charge-transfer adducts of composition 2:1 of acceptor to donor, [(acceptor)2(donor)]. Formation constants, K, as well as the thermodynamic parameters, ΔH°, ΔS°, and ΔG° were determined by UV-Vis titration method for the adducts.

Free Carrier Generation in Fullerene Acceptors and Its Effect on Polymer Photovoltaics

KAUST Repository

Burkhard, George F.; Hoke, Eric T.; Beiley, Zach M.; McGehee, Michael D.

2012-01-01

Early research on C60 led to the discovery that the absorption of photons with energy greater than 2.35 eV by bulk C60 produces free charge carriers at room temperature. We find that not only is this also true for many of the soluble fullerene derivatives commonly used in organic photovoltaics, but also that the presence of these free carriers has significant implications for the modeling, characterization, and performance of devices made with these materials. We demonstrate that the discrepancy between absorption and quantum efficiency spectra in P3HT:PCBM is due to recombination of such free carriers in large PCBM domains before they can be separated at a donor/acceptor interface. Since most theories assume that all free charges result from the separation of excitons at a donor/acceptor interface, the presence of free carrier generation in fullerenes can have a significant impact on the interpretation of data generated by numerous field-dependent techniques. © 2012 American Chemical Society.

Free Carrier Generation in Fullerene Acceptors and Its Effect on Polymer Photovoltaics

KAUST Repository

Burkhard, George F.

2012-12-20

Early research on C60 led to the discovery that the absorption of photons with energy greater than 2.35 eV by bulk C60 produces free charge carriers at room temperature. We find that not only is this also true for many of the soluble fullerene derivatives commonly used in organic photovoltaics, but also that the presence of these free carriers has significant implications for the modeling, characterization, and performance of devices made with these materials. We demonstrate that the discrepancy between absorption and quantum efficiency spectra in P3HT:PCBM is due to recombination of such free carriers in large PCBM domains before they can be separated at a donor/acceptor interface. Since most theories assume that all free charges result from the separation of excitons at a donor/acceptor interface, the presence of free carrier generation in fullerenes can have a significant impact on the interpretation of data generated by numerous field-dependent techniques. © 2012 American Chemical Society.

Michael Polanyi: Patriarch of Chemical Dynamics and Tacit Knowing.

Science.gov (United States)

Herschbach, Dudley R

2017-03-20

Connecting Science and the Humanities was the title of the symposium on Michael Polanyi that took place at the Technische Universität Berlin (Technical University of Berlin) in October 2016. This essay, which appraises the scientific and philosophical contributions of Michael Polanyi, is based on the presentation given by Dr. Herschbach on this occasion. In the photograph: Polanyi in 1931. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Nanographenes as electron-deficient cores of donor-acceptor systems.

Science.gov (United States)

Liu, Yu-Min; Hou, Hao; Zhou, Yan-Zhen; Zhao, Xin-Jing; Tang, Chun; Tan, Yuan-Zhi; Müllen, Klaus

2018-05-15

Conjugation of nanographenes (NGs) with electro-active molecules can establish donor-acceptor π-systems in which the former generally serve as the electron-donating moieties due to their electronic-rich nature. In contrast, here we report a series of reversed donor-acceptor structures are obtained by C-N coupling of electron-deficient perchlorinated NGs with electron-rich anilines. Selective amination at the vertexes of the NGs is unambiguously shown through X-ray crystallography. By varying the donating ability of the anilino groups, the optical and assembly properties of donor-acceptor NGs can be finely modulated. The electron-deficient concave core of the resulting conjugates can host electron-rich guest molecules by intermolecular donor-acceptor interactions and gives rise to charge-transfer supramolecular architectures.

Syntheses of donor-acceptor-functionalized dihydroazulenes

DEFF Research Database (Denmark)

Broman, Søren Lindbæk; Jevric, Martyn; Bond, Andrew

2014-01-01

The dihydroazulene (DHA)/vinylheptafulvene (VHF) photo/thermoswitch has been of interest for use in molecular electronics and advanced materials. The switching between the two isomers has previously been found to depend strongly on the presence of donor and acceptor groups. The fine-tuning of opt......The dihydroazulene (DHA)/vinylheptafulvene (VHF) photo/thermoswitch has been of interest for use in molecular electronics and advanced materials. The switching between the two isomers has previously been found to depend strongly on the presence of donor and acceptor groups. The fine...

Video interview with Michael Dell

CERN Multimedia

CERN Bulletin

2010-01-01

Michael Dell, founder and presently Chairman of the Board of Directors and Chief Executive Office of the DELL computer company visited CERN on Tuesday 26th January 2010. The Bulletin and the Video productions team had the opportunity to meet him. The video interview is transcribed for your convenience.   Michael S. Dell with CERN Director-General Rolf Heuer. What motivated you to come and visit CERN? I obviously heard about the great science and research has going on here, and DELL is very pleased to be a partner and providing a lot of the computers to analyse the data and I really wanted to see for myself in person, some of the great science that is going on here. What is your view on fundamental research in IT, and in general? I think if you look at the field of science in the last hundred years, we have been able to solve a lot of problems, but there are still lots of unsolved problems and unsolved mysteries. And it is only through basic fundamental research that we will address these probl...

Synthesis and electrochemical properties of novel, donor–acceptor pyrrole derivatives with 1,8-naphthalimide units and their polymers

International Nuclear Information System (INIS)

Ledwon, Przemyslaw; Brzeczek, Alina; Pluczyk, Sandra; Jarosz, Tomasz; Kuznik, Wojciech; Walczak, Krzysztof; Lapkowski, Mieczyslaw

2014-01-01

A new class of bipolar monomers with pyrrole or thiophene–pyrrole–thiophene as electron donor and 1,8-naphthalimide as electron acceptor unit is reported. Donor–acceptor conjugated polymers were generated electrochemically. The synthesis of monomers, optical, electrochemical and spectroelectrochemical properties supported by theoretical calculations are presented. 1,8-naphthalimide units were attached directly to pyrrole in compounds 1a and 2a or by different bridges in the case of 1b and 2b. Intra-molecular donor–acceptor interactions of the monomers and its polymers were investigated using cyclic voltammetry, in-situ UV–Vis-NIR, electron spin resonance (ESR) spectroelectrochemistry and fluorescence spectroscopy. Studied compounds present large discrepancy (up to 1.31 eV for 2a) between energy gap values determined through electrochemical and optical measurements. The Time-dependent density functional theory (TDDFT) calculations help to explain this discrepancy. This is caused by weak HOMO to LUMO transition, 2000 times weaker than HOMO −2 to LUMO or HOMO to LUMO +1 transition. Altering the structure of monomers yields different stability and properties of obtained polymers. The p- and n-doping processes are separated. Anions are localized mainly on 1,8-naphthalimide units. Cations are localized mainly on pyrrole or thiophene–pyrrole–thiophene moiety and their polymer chains. Attachment of the additional thiophene units decreases the oxidation potential of the monomer and reduces the influence of the steric hindrance between 1,8-naphthalimide moiety and polymer/oligomers chain. This new class of model compounds is promising for use as a material with enhanced charge separation for wide range of optoelectronic, electrochromic and photovoltaic applications

Reflections on Michael Hardt and Antonio Negri’s Book “Assembly”

Directory of Open Access Journals (Sweden)

Christian Fuchs

2017-10-01

Full Text Available This contribution presents reflections on Michael Hardt and Antonio Negri’s book “Assembly” (2017, Oxford: Oxford University Press, ISBN 978-0190677961. Keywords: assembly, Michael Hardt, Antonio Negri, multitude, common, entrepreneurship of the multitude, the new Prince, digital capitalism, digital assemblage, neoliberalism, finance

Radiation curable Michael addition compounds

International Nuclear Information System (INIS)

Gruber, G.W.; Friedlander, C.B.; McDonald, W.H.; Dowbenko, R.

1979-01-01

Radiation polymerizable acrylyloxy-containing reaction products are provided from Michael addition reaction of an amide containing at least two acrylate groups with a primary or secondary amine. The resulting amine adducts of the amide, which contain at least one acrylate group per molecule, possesses high cure rates in air and are useful in compositions for forming coatings. (author)

Impact of Thermal Annealing on Organic Photovoltaic Cells Using Regioisomeric Donor-Acceptor-Acceptor Molecules.

Science.gov (United States)

Zhang, Tao; Han, Han; Zou, Yunlong; Lee, Ying-Chi; Oshima, Hiroya; Wong, Ken-Tsung; Holmes, Russell J

2017-08-02

We report a promising set of donor-acceptor-acceptor (D-A-A) electron-donor materials based on coplanar thieno[3,2-b]/[2,3-b]indole, benzo[c][1,2,5]thiadiazole, and dicyanovinylene, which are found to show broadband absorption with high extinction coefficients. The role of the regioisomeric electron-donating thienoindole moiety on the physical and structural properties is examined. Bulk heterojunction (BHJ) organic photovoltaic cells (OPVs) based on the thieno[2,3-b]indole-based electron donor NTU-2, using C 70 as an electron acceptor, show a champion power conversion efficiency of 5.2% under AM 1.5G solar simulated illumination. This efficiency is limited by a low fill factor (FF), as has previously been the case in D-A-A systems. In order to identify the origin of the limited FF, further insight into donor layer charge-transport behavior is realized by examining planar heterojunction OPVs, with emphasis on the evolution of film morphology with thermal annealing. Compared to as-deposited OPVs that exhibit insufficient donor crystallinity, crystalline OPVs based on annealed thin films show an increase in the short-circuit current density, FF, and power conversion efficiency. These results suggest that that the crystallization of D-A-A molecules might not be realized spontaneously at room temperature and that further processing is needed to realize efficient charge transport in these materials.

Some pharmacological effects of cinnamon and ginger herbs in obese diabetic rats

Science.gov (United States)

Shalaby, Mostafa Abbas; Saifan, Hamed Yahya

2014-01-01

Aims: The present study was designed to assess some pharmacological effects of cinnamon (CAE) and ginger (GAE) aqueous extracts in obese diabetic rats, and to elucidate the potential mechanisms. Materials and Methods: Forty-two Sprague-Dawley rats were randomized into 6 equal groups. Group 1 was a negative control and the other groups were rendered obese by feeding rats on high-fat diet for 4 weeks. The obese rats were subcutaneously injected with alloxan for 5*days to induce diabetes. Group 2 was a positive control, and Groups 3, 4, 5 and 6 were orally given CAE in doses 200 and 400 mg/kg and GAE in the same doses, respectively for 6 weeks. Blood samples were collected for serum biochemical analyses. Kidneys were dissected out to assay activity of tissue antioxidant enzymes: Superoxide dismutase, glutathione peroxidase and catalase. Results: CAE and GAE significantly reduced body weight and body fat mass; normalized serum levels of liver enzymes; improved lipid profile; decreased blood glucose and leptin and increased insulin serum levels in obese diabetic rats. Both extracts also increased activity of kidney antioxidant enzymes. Conclusion: CAE and GAE exhibit anti-obesity, hepatoprotective, hypolipidemic, antidiabetic and anti-oxidant effects in obese diabetic rats. These results confirm the previous reports on both extracts. The potential mechanisms underlying these effects are fully discussed and clarified. Our results affirm the traditional use of cinnamon and ginger for treating patients suffering from obesity and diabetes. The obese diabetic rat model used in this study is a novel animal model used in pharmacology researches. PMID:26401364

Highly solvatochromic emission of electron donor-acceptor compounds containing propanedioato boron electron acceptors

NARCIS (Netherlands)

Brouwer, A.M.; Bakker, N.A.C.; Wiering, P.G.; Verhoeven, J.W.

1991-01-01

Light-induced electron transfer occurs in bifunctional compounds consisting of 1,3-diphenylpropanedioato boron oxalate or fluoride electron acceptors and simple aromatic electron-donor groups, linked by a methylene bridge; fluorescence from the highly polar charge-transfer excited state is

Dependence of the Mg-related acceptor ionization energy with the acceptor concentration in p-type GaN layers grown by molecular beam epitaxy

International Nuclear Information System (INIS)

Brochen, Stéphane; Brault, Julien; Chenot, Sébastien; Dussaigne, Amélie; Leroux, Mathieu; Damilano, Benjamin

2013-01-01

Hall effect and capacitance-voltage C(V) measurements were performed on p-type GaN:Mg layers grown on GaN templates by molecular beam epitaxy with a high range of Mg-doping concentrations. The free hole density and the effective dopant concentration N A −N D as a function of magnesium incorporation measured by secondary ion mass spectroscopy clearly reveal both a magnesium doping efficiency up to 90% and a strong dependence of the acceptor ionization energy Ea with the acceptor concentration N A . These experimental observations highlight an isolated acceptor binding energy of 245±25 meV compatible, at high acceptor concentration, with the achievement of p-type GaN:Mg layers with a hole concentration at room temperature close to 10 19 cm −3

Markets, Marx, Modernity and Mathematics Education: A Response to Michael Apple.

Science.gov (United States)

Gates, Peter

This paper is a response to Michael Apple's paper, "What Postmodernists Forget: Cultural Capital and Official Knowledge." The paper advocates Michael's identification of the current dangers and processes of the growth of new right ideologies in the development of subjectivity, society, and education. The differences in success in the education…

Loss mechanisms in organic solar cells based on perylene diimide acceptors studied by time-resolved photoluminescence

KAUST Repository

Gerhard, Marina

2016-04-27

In organic photovoltaics (OPV), perylene diimide (PDI) acceptor materials are promising candidates to replace the commonly used, but more expensive fullerene derivatives. The use of alternative acceptor materials however implies new design guidelines for OPV devices. It is therefore important to understand the underlying photophysical processes, which either lead to charge generation or geminate recombination. In this contribution, we investigate radiative losses in a series of OPV materials based on two polymers, P3HT and PTB7, respectively, which were blended with different PDI derivatives. Our time-resolved photoluminescence measurements (TRPL) allow us to identify different loss mechanisms by the decay characteristics of several excitonic species. In particular, we find evidence for unfavorable morphologies in terms of large-scale pure domains, inhibited exciton transport and incomplete charge transfer. Furthermore, in one of the P3HT-blends, an interfacial emissive charge transfer (CT) state with strong trapping character is identified. © (2016) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.

Loss mechanisms in organic solar cells based on perylene diimide acceptors studied by time-resolved photoluminescence

KAUST Repository

Gerhard, Marina; Gehrig, Dominik; Howard, Ian A.; Arndt, Andreas P.; Bilal, Mü henad; Rahimi-Iman, Arash; Lemmer, Uli; Laquai, Fré dé ric; Koch, Martin

2016-01-01

In organic photovoltaics (OPV), perylene diimide (PDI) acceptor materials are promising candidates to replace the commonly used, but more expensive fullerene derivatives. The use of alternative acceptor materials however implies new design guidelines for OPV devices. It is therefore important to understand the underlying photophysical processes, which either lead to charge generation or geminate recombination. In this contribution, we investigate radiative losses in a series of OPV materials based on two polymers, P3HT and PTB7, respectively, which were blended with different PDI derivatives. Our time-resolved photoluminescence measurements (TRPL) allow us to identify different loss mechanisms by the decay characteristics of several excitonic species. In particular, we find evidence for unfavorable morphologies in terms of large-scale pure domains, inhibited exciton transport and incomplete charge transfer. Furthermore, in one of the P3HT-blends, an interfacial emissive charge transfer (CT) state with strong trapping character is identified. © (2016) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.

Progress in ZnO Acceptor Doping: What Is the Best Strategy?

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Judith G. Reynolds

2014-01-01

Full Text Available This paper reviews the recent progress in acceptor doping of ZnO that has been achieved with a focus toward the optimum strategy. There are three main approaches for generating p-type ZnO: substitutional group IA elements on a zinc site, codoping of donors and acceptors, and substitution of group VA elements on an oxygen site. The relevant issues are whether there is sufficient incorporation of the appropriate dopant impurity species, does it reside on the appropriate lattice site, and lastly whether the acceptor ionization energy is sufficiently small to enable significant p-type conduction at room temperature. The potential of nitrogen doping and formation of the appropriate acceptor complexes is highlighted although theoretical calculations predict that nitrogen on an oxygen site is a deep acceptor. We show that an understanding of the growth and annealing steps to achieve the relevant acceptor defect complexes is crucial to meet requirements.

Influence of acceptor on charge mobility in stacked π-conjugated polymers

Science.gov (United States)

Sun, Shih-Jye; Menšík, Miroslav; Toman, Petr; Gagliardi, Alessio; Král, Karel

2018-02-01

We present a quantum molecular model to calculate mobility of π-stacked P3HT polymer layers with electron acceptor dopants coupled next to side groups in random position with respect to the linear chain. The hole density, the acceptor LUMO energy and the hybridization transfer integral between the acceptor and polymer were found to be very critical factors to the final hole mobility. For a dopant LUMO energy close and high above the top of the polymer valence band we have found a significant mobility increase with the hole concentration and with the dopant LUMO energy approaching the top of the polymer valence band. Higher mobility was achieved for small values of hybridization transfer integral between polymer and the acceptor, corresponding to the case of weakly bound acceptor. Strong couplings between the polymer and the acceptor with Coulomb repulsion interactions induced from the electron localizations was found to suppress the hole mobility.

Characteristics of ovulation method acceptors: a cross-cultural assessment.

Science.gov (United States)

Klaus, H; Labbok, M; Barker, D

1988-01-01

Five programs of instruction in the ovulation method (OM) in diverse geographic and cultural settings are described, and characteristics of approximately 200 consecutive OM acceptors in each program are examined. Major findings include: the religious background and family size of acceptors are variable, as is the level of previous contraceptive use. Acceptors are drawn from a wide range of socioeconomic and religious backgrounds; however, family planning intention was similarly distributed in all five countries. In sum, the ovulation method is accepted by persons from a variety of backgrounds within and between cultural setting.

Theory of Primary Photoexcitations in Donor-Acceptor Copolymers.

Science.gov (United States)

Aryanpour, Karan; Dutta, Tirthankar; Huynh, Uyen N V; Vardeny, Zeev Valy; Mazumdar, Sumit

2015-12-31

We present a generic theory of primary photoexcitations in low band gap donor-acceptor conjugated copolymers. Because of the combined effects of strong electron correlations and broken symmetry, there is considerable mixing between a charge-transfer exciton and an energetically proximate triplet-triplet state with an overall spin singlet. The triplet-triplet state, optically forbidden in homopolymers, is allowed in donor-acceptor copolymers. For an intermediate difference in electron affinities of the donor and the acceptor, the triplet-triplet state can have a stronger oscillator strength than the charge-transfer exciton. We discuss the possibility of intramolecular singlet fission from the triplet-triplet state, and how such fission can be detected experimentally.

Cinnamon from the selection of traditional applications to its novel effects on the inhibition of angiogenesis in cancer cells and prevention of Alzheimer's disease, and a series of functions such as antioxidant, anticholesterol, antidiabetes, antibacterial, antifungal, nematicidal, acaracidal, and repellent activities

OpenAIRE

Hamidpour, Rafie; Hamidpour, Mohsen; Hamidpour, Soheila; Shahlari, Mina

2015-01-01

The purpose of this article is to use search engines such as PubMed and Scifinder to locate scholarly articles and reports pertaining to Cinnamon (?? r?u gu?), its novel effects, preparation, analysis, and use in the prevention and treatment of serious illnesses, such as diabetes, cardiovascular diseases, Alzheimer?s disease, and cancer. Cinnamon has been used traditionally in food preparations and as an herbal medicine to treat a variety of ailments and their symptoms. Cinnamon is known to h...

Absorption from Neutral Acceptors in GaAs and GaP

DEFF Research Database (Denmark)

Christensen, Ove

1973-01-01

We present a new calculation of the absorption due to transitions of holes between neutral acceptors and the various valence-band sublevels in GaAs and GaP. The acceptor wave function was approximated by a previously suggested expression for ground-state wave functions appropriate to complicated...... band extrema. Numerical calculations of the absorption from intervalence-band transitions of free holes and neutral acceptors have been performed. Good agreement with experimental results is obtained....

Aza-Michael reaction: achievements and prospects

International Nuclear Information System (INIS)

Rulev, Alexander Yu

2011-01-01

Data published in the last 10 years on the use of the aza-Michael reaction in organic synthesis are described systematically. The attention is focused on environmentally friendly processes following green chemistry principles and on methods for the synthesis of compounds that are difficult to access by other routes.

Reactions of Fischer carbene complexes with Electron-deficient olefins: Scope and limitations of this route to donor-acceptor-substituted cyclopropanes

Energy Technology Data Exchange (ETDEWEB)

Wienand, A.; Reissig, H.U. (Inst. fuer Organische Chemie der Technischen Hochschule Darmstadt (West Germany))

1990-12-01

The Fischer carbene complex ((CO){sub 5}Cr{double bond}C(OMe)Ph) (1) is able to transfer its carbene ligand to a variety of electron-deficient olefins and provides donor-acceptor-substituted cyclopropanes in good yields. Apt activating groups with respect to the alkene are ester, amide, nitrile, sulfone, and dialkyl phosphonate functions. Methyl vinyl ketone (19) affords products in low yield that may arise from an intermediate cyclopropane derivative. Phenyl vinyl sulfoxide (24) mainly acts as an oxidizing agent, transforming 1 into methyl benzoate. for olefin 24 and {alpha}-(N-methylanilino)acrylonitrile the authors found products that should be formed on an olefin metathesis pathway. The methyl-substituted carbene complex 48 also affords the expected donor-acceptor-substituted cyclopropanes; however, acyclic isomers are formed in higher amounts. The molybdenum and tungsten complexes 55 and 56, respectively, also furnish cyclopropane derivatives, but the yields are lower than with the chromium compound 1. Disubstituted olefins and complex 1 still give the cyclopropanes in moderate yields, while all trisubstituted and most of the difunctionalized alkenes do not react with this Fischer carbene complex. The cyclopropanes synthesized can be deprotonated and alkylated or transformed into ring-opened products. These model reactions demonstrate the synthetic potentials of donor-acceptor-substituted cyclopropanes prepared via Fischer carbene complexes.

Deactivation of group III acceptors in silicon during keV electron irradiation

International Nuclear Information System (INIS)

Sah, C.; Sun, J.Y.; Tzou, J.J.; Pan, S.C.

1983-01-01

Experimental results on p-Si metal-oxide-semiconductor capacitors (MOSC's) are presented which demonstrate the electrical deactivation of the acceptor dopant impurity during 8-keV electron irradiation not only in boron but also aluminum and indium-doped silicon. The deactivation rates of the acceptors during the 8-keV electron irradiation are nearly independent of the acceptor impurity type. The final density of the remaining active acceptor approaches nonzero values N/sub infinity/, with N/sub infinity/(B) Al--H>In-H. These deactivation results are consistent with our hydrogen bond model. The thermal annealing or regeneration rate of the deactivated acceptors in the MOSC's irradiated by 8-keV electron is much smaller than that in the MOSC's that have undergone avalanche electron injection, indicating that the keV electron irradiation gives rise to stronger hydrogen-acceptor bond

Positronium Inhibition and Quenching by Organic Electron Acceptors and Charge Transfer Complexes

DEFF Research Database (Denmark)

Jansen, P.; Eldrup, Morten Mostgaard; Jensen, Bror Skytte

1975-01-01

Positron lifetime measurements were performed on a series of organic electron acceptors and charge-transfer complexes in solution. The acceptors cause both positronium (Ps) inhibition (with maybe one exception) and quenching, but when an acceptor takes part in a charge-transfer complex...... in terms of the spur reaction model of Ps formation. Correlation was also made to gas phase reaction between electron acceptors and free electron, as well as to pulse radiolysis data....

Fascinating transformations of donor-acceptor complexes of group 13 metal (Al, Ga, In) derivatives with nitriles and isonitriles: from monomeric cyanides to rings and cages.

Science.gov (United States)

Timoshkin, Alexey Y; Schaefer, Henry F

2003-08-20

Formation of the donor-acceptor complexes of group 13 metal derivatives with nitriles and isonitriles X(3)M-D (M = Al,Ga,In; X = H,Cl,CH(3); D = RCN, RNC; R = H,CH(3)) and their subsequent reactions have been theoretically studied at the B3LYP/pVDZ level of theory. Although complexation with MX(3) stabilizes the isocyanide due to the stronger M-C donor-acceptor bond, this stabilization (20 kJ mol(-1) at most) is not sufficient to make the isocyanide form more favorable. Relationships between the dissociation enthalpy DeltaH degrees (298)(diss), charge-transfer q(CT), donor-acceptor bond energy E(DA), and the shift of the vibrational stretching mode of the CN group upon coordination Deltaomega(CN) have been examined. For a given metal center, there is a good correlation between the energy of the donor-acceptor bond and the degree of a charge transfer. Prediction of the DeltaH degrees (298)(diss) on the basis of the shift of CN stretching mode is possible within limited series of cyanide complexes (for the fixed M,R); in contrast, complexes of the isocyanides exhibit very poor Deltaomega(CN) - DeltaH degrees (298)(diss) correlation. Subsequent X ligand transfer and RX elimination reactions yielding monomeric (including donor-acceptor stabilized) and variety of oligomeric cage and ring compounds with [MN]n, [MC]n, [MNC]n cores have been considered and corresponding to thermodynamic characteristics have been obtained for the first time. Monomeric aluminum isocyanides X(2)AlNC are more stable compared to Al-C bonded isomers; for gallium and indium situation is reversed, in qualitative agreement with Pearson's HSAB concept. Substitution of X by CN in MX(3) increases the dissociation enthalpy of the MX(2)CN-NH(3) complex compared to that for MX(3)-NH(3), irrespective of the substituent X. Mechanisms of the initial reaction of the X transfer have been studied for the case X = R = H. The process of hydrogen transfer from the metal to the carbon atom in H(3)M-CNH is

Michael Jackson's Sound Stages

OpenAIRE

Morten Michelsen

2012-01-01

In order to discuss analytically spatial aspects of recorded sound William Moylan’s concept of ‘sound stage’ is developed within a musicological framework as part of a sound paradigm which includes timbre, texture and sound stage. Two Michael Jackson songs (‘The Lady in My Life’ from 1982 and ‘Scream’ from 1995) are used to: a) demonstrate the value of such a conceptualisation, and b) demonstrate that the model has its limits, as record producers in the 1990s began ignoring the conventions of...

Facile Iodine-Catalyzed Michael Addition of Indoles to α,α′-Bis(arylmethylene)cyclopentanones: An Efficient Synthesis of E-2-(3-Indolylphenylmethyl)-5-phenylmethylenecyclopentanones

Science.gov (United States)

Pal, Rammohan; Das Gupta, Arpita; Mallik, Asok K.

2012-01-01

Iodine-catalyzed reaction of indoles with α,α′-bis(arylmethylene)cyclopentanones afforded one diastereomer of the corresponding Michael adducts, namely, E-2-(3-indolylphenylmethyl)-5-phenylmethylenecyclopentanones, in a good yield. The products form a new group of indole derivatives. PMID:24052849

Studying Teachers and Schools: Michael Pressley's Legacy and Directions for Future Research

Science.gov (United States)

Mohan, Lindsey; Lundeberg, Mary A.; Reffitt, Kelly

2008-01-01

Much of Michael Pressley's work during the past decade focused on the nature of highly effective, engaging literacy instruction. Michael Pressley believed that studying effective teachers and schools had the potential to influence more engaging and effective teaching, especially in underresourced schools. First, we describe the grounded…

Modeling charge transfer at organic donor-acceptor semiconductor interfaces

NARCIS (Netherlands)

Cakir, Deniz; Bokdam, Menno; de Jong, Machiel Pieter; Fahlman, M.; Brocks, G.

2012-01-01

We develop an integer charge transfer model for the potential steps observed at interfaces between donor and acceptor molecular semiconductors. The potential step can be expressed as the difference between the Fermi energy pinning levels of electrons on the acceptor material and holes on the donor

Acceptors in II-IV Semiconductors - Incorporation and Complex Formation

CERN Multimedia

2002-01-01

A strong effort is currently devoted to the investigation of defects and the electrical activation of dopant atoms in II-VI semiconductors. In particular, the knowledge about the behaviour of acceptors, prerequisite for the fabrication of p-type semiconductors, is rather limited. The perturbed $\\,{\\gamma\\gamma}$ -angular correlation technique (PAC) and the photoluminescence spectroscopy (PL) using the radioactive isotopes $^{77}\\!$Br and $^{111}\\!$Ag will be applied for investigating the behaviour of acceptor dopant atoms and their interactions with defects in II-VI semiconductors. The main topic will be the identification of the technical conditions for the incorporation of electrically active acceptors in the II-VI semiconductors ~ZnS, ZnSe, ZnTe, CdS, CdSe, and CdTe with particular emphasis on the compounds~ CdTe, ZnSe, and ZnTe. The investigations will be supplemented by first exploratory PL experiments with the group V acceptors $^{71}\\!$As and $^{121}\\!$Sb. With help of the probe $^{111}\\!$Ag, the pos...

En memoria de Michael Jiménez (1948-2001

Directory of Open Access Journals (Sweden)

Mauricio Archila Neira

2001-01-01

Full Text Available El 1 de septiembre de 2001 murió el historiador Michael Jiménez. Su apellido provenía de España de donde emigró su abuelo en busca de mejor suerte al otro lado del Atlántico. Nacido en el pequeño pueblo de Merced, California (Estados Unidos en agosto de 1948 en el seno de una familia obrera, Michael vivió su infancia en Colombia. A fines de ese año, su padre se desplazó a estas tierras para ser funcionario de la Texas, una multinacional petrolera que tenía sus reales en Puerto Boyacá. Michael estudió en el colegio Nueva Granada -becado por la Texas- hasta los catorce años. En dicho colegio fue compañero de pupitre de Herbert Braun, descendiente a su vez de una familia de emigrantes a Colombia, y con quien la vida lo juntaría de nuevo en las tierras del norte y en oficios similares.

Fluorescent and colorimetric molecular recognition probe for hydrogen bond acceptors.

Science.gov (United States)

Pike, Sarah J; Hunter, Christopher A

2017-11-22

The association constants for formation of 1 : 1 complexes between a H-bond donor, 1-naphthol, and a diverse range of charged and neutral H-bond acceptors have been measured using UV/vis absorption and fluorescence emission titrations. The performance of 1-naphthol as a dual colorimetric and fluorescent molecular recognition probe for determining the H-bond acceptor (HBA) parameters of charged and neutral solutes has been investigated in three solvents. The data were employed to establish self-consistent H-bond acceptor parameters (β) for benzoate, azide, chloride, thiocyanate anions, a series of phosphine oxides, phosphate ester, sulfoxide and a tertiary amide. The results demonstrate both the transferability of H-bond parameters between different solvents and the utility of the naphthol-based dual molecular recognition probe to exploit orthogonal spectroscopic techniques to determine the HBA properties of neutral and charged solutes. The benzoate anion is the strongest HBA studied with a β parameter of 15.4, and the neutral tertiary amide is the weakest H-bond acceptor investigated with a β parameter of 8.5. The H-bond acceptor strength of the azide anion is higher than that of chloride (12.8 and 12.2 respectively), and the thiocyanate anion has a β value of 10.8 and thus is a significantly weaker H-bond acceptor than both the azide and chloride anions.

Tribute to Professor Anthony J. McMichael

Directory of Open Access Journals (Sweden)

Ashwin Swaminathan

2014-11-01

Full Text Available Emeritus Professor A. J. “Tony” McMichael (1942–2014 was an internationally renowned and pioneering Australian academic and advocate in epidemiology, who was passionate about understanding the influences of the environment on human health. In an illustrious career spanning more than four decades, he made significant contributions to the scientific community and policy discourse—including ground-breaking research related to the health of children. McMichael was a prolific academic writer with over 300 peer-reviewed papers; 160 book chapters and two sole-authored books. However, his outstanding talent was for integrating complex and seemingly unrelated strands from the environmental and health sciences into a cohesive narrative—and highlighting its relevance to lay persons, scientists and governments alike. He was instrumental in validating this nascent field of research and inspiring many others to follow his lead.

Inserção de catalisador híbrido na síntese de beta-tiocetonas

Directory of Open Access Journals (Sweden)

Mariana Pompilio Darbem

2012-06-01

Full Text Available The Michael reaction (or Michael addition involves the addition of a nucleophile, called Michael donor, to an electrophile (α,β-unsaturated, called Michael acceptor. Literature reports several types of nucleophiles applied in this reaction. Among them we can mention compounds containing a sulfur atom. When these nucleophiles are applied to this reaction, it is called as thia-Michael reaction. In this study thiophenol, p- chlorothiophenol and p-methoxythiophenol were tested as Michael donors, and several ketones and aldehydes as Michael acceptors, in order to obtain the formation of sigma bonds carbon-sulfur. Compounds that have in their structure the C-S bond are extremely important, because they can present, for example, antibiotic action, antimicrobial analgesic, and anti-HIV. This research proposes, besides the obtainment of  many beta-thioketonic compounds, the insertion of a new catalyst in thia-Michael reactions, the bis-L-zinc prolinate. This catalyst provided the obtainment of high yield compounds. The reactions were executed using ultrasound, which caused a significant decrease in the reaction time and an increase in the results obtained when compared with data obtained previously in literature. An important fact in this study is that the catalyst used is not soluble in the reaction media and it can be reused without abrupt loss of yield.

The effect of intramolecular donor–acceptor moieties with donor–π-bridge–acceptor structure on the solar photovoltaic performance

Directory of Open Access Journals (Sweden)

T. L. Wang

2015-10-01

Full Text Available A series of intramolecular donor–acceptor polymers containing different contents of (E-1-(2-ethylhexyl-6,9-dioctyl-2-(2-(thiophen-3-ylvinyl-1H-phenanthro[9,10-d]imidazole (thiophene-DOPI moiety and 4,4-diethylhexylcyclopenta[ 2,1-b:3,4-b']dithiophene (CPDT unit was synthesized via Grignard metathesis (GRIM polymerization. The synthesized random copolymers and homopolymer of thiophene-DOPI contain the donor–π-bridge–acceptor conjugated structure to tune the absorption spectra and energy levels of the resultant polymers. UV-vis spectra of the three polymer films exhibit panchromatic absorptions ranging from 300 to 1100 nm and low band gaps from 1.38 to 1.51 eV. It is found that more thiophene-DOPI moieties result in the decrease of band gap and lower the highest occupied molecular orbital (HOMO and lowest unoccupied molecular orbital (LUMO values of polymers. Photovoltaic performance results indicate that if the content of the intramolecular donor–acceptor moiety is high enough, the copolymer structure may be better than homopolymer due to more light-harvesting afforded by both monomer units.

Improving Photoconductance of Fluorinated Donors with Fluorinated Acceptors

Energy Technology Data Exchange (ETDEWEB)

Garner, Logan E.; Larson, Bryon; Oosterhout, Stefan; Owczarczyk, Zbyslaw; Olson, Dana C.; Kopidakis, Nikos; Boltalina, Olga V.; Strauss, Steven H.; Braunecker, Wade A.

2016-11-21

This work investigates the influence of fluorination of both donor and acceptor materials on the generation of free charge carriers in small molecule donor/fullerene acceptor BHJ OPV active layers. A fluorinated and non-fluorinated small molecule analogue were synthesized and their optoelectronic properties characterized. The intrinsic photoconductance of blends of these small molecule donors was investigated using time-resolved microwave conductivity. Blends of the two donor molecules with a traditional non-fluorinated fullerene (PC70BM) as well as a fluorinated fullerene (C60(CF3)2-1) were investigated using 5% and 50% fullerene loading. We demonstrate for the first time that photoconductance in a 50:50 donor:acceptor BHJ blend using a fluorinated fullerene can actually be improved relative to a traditional non-fluorinated fullerene by fluorinating the donor molecule as well.

Spatial structure of single and interacting Mn acceptors in GaAs

Science.gov (United States)

Koenraad, Paul

2005-03-01

Ferromagnetic semiconductors such as Ga1-xMnxAs are receiving a lot of attention at the moment because of their application in spintronic devices. However, despite intense study of deep acceptors in III-V semiconductors such as MnGa, little information has been obtained on their electronic properties at the atomic scale. Yet the spatial shape of the Mn acceptor state will influence the hole-mediated Mn-Mn coupling and thus all of the magnetic properties of ferromagnetic semiconductors such as Ga1-xMnxAs. This study presents an experimental and theoretical description of the spatial symmetry of the Mn acceptor wave-function in GaAs. We present measurements of the spatial mapping of the anisotropic wavefunction of a hole localized at a Mn acceptor. To achieve this, we have used the STM tip not only to image the Mn acceptor but also to manipulate its charge state A^0/A^- at room temperature. Within an envelope function effective mass model (EFM) the anisotropy in the acceptor wave-function can be traced to the influence of the cubic symmetry of the GaAs crystal which selects specific d-states that mix into the ground state due to the spin-orbit interaction in the valence band. Comparison with calculations based on a tight-binding model (TBM) for the Mn acceptor structure supports this conclusion. Using the same experimental and theoretical approach we furthermore explored the interaction between Mn acceptors directly by analyzing close Mn-Mn pairs, which were separated by less than 2 nm. We will discuss some implications of these results for Mn delta-doped layers grown on differently oriented growth surfaces.

Template Dimerization Promotes an Acceptor Invasion-Induced Transfer Mechanism during Human Immunodeficiency Virus Type 1 Minus-Strand Synthesis

Science.gov (United States)

Balakrishnan, Mini; Roques, Bernard P.; Fay, Philip J.; Bambara, Robert A.

2003-01-01

The biochemical mechanism of template switching by human immunodeficiency virus type 1 (HIV-1) reverse transcriptase and the role of template dimerization were examined. Homologous donor-acceptor template pairs derived from the HIV-1 untranslated leader region and containing the wild-type and mutant dimerization initiation sequences (DIS) were used to examine the efficiency and distribution of transfers. Inhibiting donor-acceptor interaction was sufficient to reduce transfers in DIS-containing template pairs, indicating that template dimerization, and not the mere presence of the DIS, promotes efficient transfers. Additionally, we show evidence that the overall transfer process spans an extended region of the template and proceeds through a two-step mechanism. Transfer is initiated through an RNase H-facilitated acceptor invasion step, while synthesis continues on the donor template. The invasion then propagates towards the primer terminus by branch migration. Transfer is completed with the translocation of the primer terminus at a site distant from the invasion point. In our system, most invasions initiated before synthesis reached the DIS. However, transfer of the primer terminus predominantly occurred after synthesis through the DIS. The two steps were separated by 60 to 80 nucleotides. Sequence markers revealed the position of primer terminus switch, whereas DNA oligomers designed to block acceptor-cDNA interactions defined sites of invasion. Within the region of homology, certain positions on the template were inherently more favorable for invasion than others. In templates with DIS, the proximity of the acceptor facilitates invasion, thereby enhancing transfer efficiency. Nucleocapsid protein enhanced the overall efficiency of transfers but did not alter the mechanism. PMID:12663778

Utilization of carrageenan, citric acid and cinnamon oil as an edible coating of chicken fillets to prolong its shelf life under refrigeration conditions.

Science.gov (United States)

Khare, Anshul Kumar; Abraham, Robinson J J; Appa Rao, V; Babu, R Narendra

2016-02-01

The present study was conducted to determine efficacy of edible coating of carrageenan and cinnamon oil to enhance the shelf life of chicken meat stored under refrigeration conditions. Chicken breast was coated with carrageenan and cinnamon oil by three methods of application viz., spraying brushing and dipping. The coated meat was evaluated for drip loss, pH, thiobarbituric acid number (TBA), tyrosine value (TV), extract release volume (ERV), Warner-Bratzler shear force value (WBSFV), instrumental color, microbiological, and sensory qualities as per standard procedures. There was a significant difference observed for physicochemical parameters (pH, TBA, TV, ERV, drip loss and WBSFV) and microbiological analysis between storage periods in all the samples and between the control and treatments throughout the storage period but samples did not differed significantly for hunter color scores. However, there was no significant difference among three methods of application throughout the storage period though dipping had a lower rate of increase. A progressive decline in mean sensory scores was recorded along with the increase in storage time. The carrageenan and cinnamon edible coating was found to be a good alternative to enhance the shelf life of chicken meat under refrigeration conditions. It was also observed from study that dipping method of the application had comparatively higher shelf life than other methods of application.

A copper-relates shallow acceptor in quenched germanium

International Nuclear Information System (INIS)

Kamiura, Yoichi; Hashimoto, Fumio; Sugiyama, Hazime; Yoneyama, Shin-ichiro

1982-01-01

The temperature variation of hole density was measured in the range 5-200 K after successive annealings at 320sup(o)C. It was found that a shallow acceptor at Esub(v) + 9 meV disappears on annealing, being replaced by a just equal additional density of substitutional copper. This provides experimental proof that the shallow acceptor is a defect complex containing at least one copper atom. (author)

Theory of Primary Photoexcitations in Donor-Acceptor Copolymers

OpenAIRE

Aryanpour, Karan; Dutta, Tirthankar; Huynh, Uyen N. V.; Vardeny, Zeev Valy; Mazumdar, Sumit

2015-01-01

We present a generic theory of primary photoexcitations in low band gap donor-acceptor conjugated copolymers. Because of the combined effects of strong electron correlations and broken symmetry, there is considerable mixing between a charge-transfer exciton and an energetically proximate triplet-triplet state with an overall spin singlet. The triplet-triplet state, optically forbidden in homopolymers, is allowed in donor-acceptor copolymers. For an intermediate difference in electron affiniti...

Photophysical properties of novel small acceptor molecules and their application in hybrid small-molecular/polymeric organic solar cells

Energy Technology Data Exchange (ETDEWEB)

Inal, Sahika; Castellani, Mauro; Neher, Dieter [Universitaet Potsdam, Institut fuer Physik und Astronomie, Potsdam-Golm (Germany); Sellinger, Alan [Institute of Materials Research and Engineering, Singapore (Singapore)

2009-07-01

Recent experimental investigations revealed that the photovoltaic properties of our devices are related to the balance between recombination and field-induced dissociation of interfacial excited states such as exciplexes or geminate polaron pairs. This balance was shown to be affected by the nanomorphology at the heterojunction. We have analyzed the photophysical properties of a new materials couple comprising an electron-donating PPV copolymer and a vinazene-based small molecule acceptor. Steady state and time-resolved photoluminescence (PL) spectroscopy in solution and in the solid state showed the formation of excimers within the acceptor. The associated long-range diffusion promise efficient energy harvesting at the heterojunction. On the other hand, blends of the PPV-derivative and the small molecule revealed strong exciplex formation. Therefore, bilayered hybrid small-molecular/polymeric solar cells have been fabricated by consequently spin-coating the macromolecular donor and the small molecule acceptor from two different solvents. The bilayer architecture limits recombination processes enabling high FFs of around 44% and a technologically important open circuit voltage of 1Volt.

Metabolic response of Geobacter sulfurreducens towards electron donor/acceptor variation

Directory of Open Access Journals (Sweden)

Lovley Derek R

2010-11-01

Full Text Available Abstract Background Geobacter sulfurreducens is capable of coupling the complete oxidation of organic compounds to iron reduction. The metabolic response of G. sulfurreducens towards variations in electron donors (acetate, hydrogen and acceptors (Fe(III, fumarate was investigated via 13C-based metabolic flux analysis. We examined the 13C-labeling patterns of proteinogenic amino acids obtained from G. sulfurreducens cultured with 13C-acetate. Results Using 13C-based metabolic flux analysis, we observed that donor and acceptor variations gave rise to differences in gluconeogenetic initiation, tricarboxylic acid cycle activity, and amino acid biosynthesis pathways. Culturing G. sulfurreducens cells with Fe(III as the electron acceptor and acetate as the electron donor resulted in pyruvate as the primary carbon source for gluconeogenesis. When fumarate was provided as the electron acceptor and acetate as the electron donor, the flux analysis suggested that fumarate served as both an electron acceptor and, in conjunction with acetate, a carbon source. Growth on fumarate and acetate resulted in the initiation of gluconeogenesis by phosphoenolpyruvate carboxykinase and a slightly elevated flux through the oxidative tricarboxylic acid cycle as compared to growth with Fe(III as the electron acceptor. In addition, the direction of net flux between acetyl-CoA and pyruvate was reversed during growth on fumarate relative to Fe(III, while growth in the presence of Fe(III and acetate which provided hydrogen as an electron donor, resulted in decreased flux through the tricarboxylic acid cycle. Conclusions We gained detailed insight into the metabolism of G. sulfurreducens cells under various electron donor/acceptor conditions using 13C-based metabolic flux analysis. Our results can be used for the development of G. sulfurreducens as a chassis for a variety of applications including bioremediation and renewable biofuel production.

Acceptors related to group I elements in ZnO ceramics

Energy Technology Data Exchange (ETDEWEB)

Kushnirenko, V.I. [V. Lashkarev Institute of Semiconductor Physics, NAS of Ukraine, Pr. Nauky 45, Kiev 03028 (Ukraine); Markevich, I.V., E-mail: ivmarkevich@ukr.net [V. Lashkarev Institute of Semiconductor Physics, NAS of Ukraine, Pr. Nauky 45, Kiev 03028 (Ukraine); Zashivailo, T.V. [National Technical University of Ukraine ' KPI' , Pr. Pobedy 37, Kiev 03056 (Ukraine)

2012-08-15

ZnO ceramics doped with Li, Na or K were sintered in air for 4 h at 1000 Degree-Sign C. Electrical conductivity as well as photoluminescence (PL), PL excitation and photoconductivity spectra were measured and compared with those in undoped samples. The influence of both fast and slow cooling of the samples from 1000 Degree-Sign C on measured characteristics was investigated. The yellow-orange PL bands associated with the deep acceptors Li{sub Zn}, Na{sub Zn} and K{sub Zn} were observed and the corresponding PL excitation spectra were determined. These acceptors were found to form some complexes with other lattice defects. - Highlights: Black-Right-Pointing-Pointer Centers related to Li, Na and K impurities in zinc oxide were investigated. Black-Right-Pointing-Pointer It was shown that Li{sub Zn}, Na{sub Zn} and K{sub Zn} centers were deep acceptors responsible for yellow-orange PL bands. Black-Right-Pointing-Pointer These acceptors were found to form some complexes with other lattice defects. Black-Right-Pointing-Pointer The formation of shallow acceptors due to doping ZnO ceramics with Li, Na and K was not found.

Michael Heyrovsky, in memoriam (1932-2017)

Czech Academy of Sciences Publication Activity Database

Barek, J.; Černý, Slavoj; Herman, Zdeněk; Jindra, Jiří; Paleček, Emil

2017-01-01

Roč. 29, č. 8 (2017), s. 2001-2002 ISSN 1040-0397 Institutional support: RVO:68378114 ; RVO:61388955 ; RVO:68081707 Keywords : Michael Heyrovský Subject RIV: AB - History OBOR OECD: History (history of science and technology to be 6.3, history of specific sciences to be under the respective headings) Impact factor: 2.851, year: 2016

Synthesis and X-ray crystal structure of the first tetrathiafulvalene-based acceptor-donor-acceptor sandwich

DEFF Research Database (Denmark)

Simonsen, Klaus B.; Thorup, Niels; Cava, Michael P.

1998-01-01

The synthesis and characterization of a bis-macrocyclic A-D-A sandwich produced in a simple one-pot reaction is reported. Only one acceptor unit participates in charge-transfer interactions with the TTF unit in the solid state....

75 FR 62635 - Proposed Information Collection (Patient Satisfaction Survey Michael E. DeBakey Home Care Program...

Science.gov (United States)

2010-10-12

... Collection (Patient Satisfaction Survey Michael E. DeBakey Home Care Program) Activity: Comment Request... determine patients' satisfaction with services provided by or through the Michael E. DeBakey Home Care...: Patient Satisfaction Survey Michael E. DeBakey Home Care Program, VA Form 10-0476. OMB Control Number...

Domino Aza-Michael-ih-Diels-Alder Reaction to Various 3-Vinyl-1,2,4-triazines: Access to Polysubstituted Tetrahydro-1,6-naphthyridines.

Science.gov (United States)

Jouha, Jabrane; Buttard, Floris; Lorion, Magali; Berthonneau, Clément; Khouili, Mostafa; Hiebel, Marie-Aude; Guillaumet, Gérald; Brière, Jean-François; Suzenet, Franck

2017-09-15

A straightforward domino aza-Michael-inverse-electron-demand-hetero-Diels-Alder/retro-Diels-Alder reaction between primary and secondary propargylamine derivatives and 3-vinyl-1,2,4-triazines is developed highlighting not only the uniqueness of this dual-heterocyclic platform but also a novel and unprecedented path to polysubstituted tetrahydro-1,6-naphthyridine scaffolds.

Michael Hauskeller: Sex and the Posthuman Condition

NARCIS (Netherlands)

Miller, Lantz Eugene

2016-01-01

This new book from Michael Hauskeller explores the currently marketed or projected sex/love products that exhibit some trait of so-called “posthumanistic” theory or design. These products are so designated because of their intention to fuse high technologies, including robotics and computing, with

Effects of a blended garlic and cinnamon essential oil extract with and without monensin sodium on the performance of grazing steers

Science.gov (United States)

A series of stocker grazing experiments were conducted with the objective to determine the efficacy of supplementing growing calf diets with essential oils from garlic and cinnamon extracts (GCOE) in promoting growth on cool-season annuals in Arkansas (SWREC) and Oklahoma (SPRRS), or native rangelan...

2012 Gordon Research Conference, Electron donor-acceptor interactions, August 5-10 2012

Energy Technology Data Exchange (ETDEWEB)

McCusker, James [Michigan State Univ., East Lansing, MI (United States)

2012-08-10

The upcoming incarnation of the Gordon Research Conference on Electron Donor Acceptor Interactions will feature sessions on classic topics including proton-coupled electron transfer, dye-sensitized solar cells, and biological electron transfer, as well as emerging areas such as quantum coherence effects in donor-acceptor interactions, spintronics, and the application of donor-acceptor interactions in chemical synthesis.

A rhodanine flanked nonfullerene acceptor for solution-processed organic photovoltaics

KAUST Repository

Holliday, Sarah

2015-01-21

A novel small molecule, FBR, bearing 3-ethylrhodanine flanking groups was synthesized as a nonfullerene electron acceptor for solution-processed bulk heterojunction organic photovoltaics (OPV). A straightforward synthesis route was employed, offering the potential for large scale preparation of this material. Inverted OPV devices employing poly(3-hexylthiophene) (P3HT) as the donor polymer and FBR as the acceptor gave power conversion efficiencies (PCE) up to 4.1%. Transient and steady state optical spectroscopies indicated efficient, ultrafast charge generation and efficient photocurrent generation from both donor and acceptor. Ultrafast transient absorption spectroscopy was used to investigate polaron generation efficiency as well as recombination dynamics. It was determined that the P3HT:FBR blend is highly intermixed, leading to increased charge generation relative to comparative devices with P3HT:PC60BM, but also faster recombination due to a nonideal morphology in which, in contrast to P3HT:PC60BM devices, the acceptor does not aggregate enough to create appropriate percolation pathways that prevent fast nongeminate recombination. Despite this nonoptimal morphology the P3HT:FBR devices exhibit better performance than P3HT:PC60BM devices, used as control, demonstrating that this acceptor shows great promise for further optimization.

Non-Fullerene Electron Acceptors for Use in Organic Solar Cells

KAUST Repository

Nielsen, Christian B.

2015-10-27

The active layer in a solution processed organic photovoltaic device comprises a light absorbing electron donor semiconductor, typically a polymer, and an electron accepting fullerene acceptor. Although there has been huge effort targeted to optimize the absorbing, energetic, and transport properties of the donor material, fullerenes remain as the exclusive electron acceptor in all high performance devices. Very recently, some new non-fullerene acceptors have been demonstrated to outperform fullerenes in comparative devices. This Account describes this progress, discussing molecular design considerations and the structure–property relationships that are emerging. The motivation to replace fullerene acceptors stems from their synthetic inflexibility, leading to constraints in manipulating frontier energy levels, as well as poor absorption in the solar spectrum range, and an inherent tendency to undergo postfabrication crystallization, resulting in device instability. New acceptors have to address these limitations, providing tunable absorption with high extinction coefficients, thus contributing to device photocurrent. The ability to vary and optimize the lowest unoccupied molecular orbital (LUMO) energy level for a specific donor polymer is also an important requirement, ensuring minimal energy loss on electron transfer and as high an internal voltage as possible. Initially perylene diimide acceptors were evaluated as promising acceptor materials. These electron deficient aromatic molecules can exhibit good electron transport, facilitated by close packed herringbone crystal motifs, and their energy levels can be synthetically tuned. The principal drawback of this class of materials, their tendency to crystallize on too large a length scale for an optimal heterojunction nanostructure, has been shown to be overcome through introduction of conformation twisting through steric effects. This has been primarily achieved by coupling two units together, forming dimers

Cinnamon Oil and Chitosan Coating on Orthopaedic Implant Surface for Prevention of Staphylococcus Epidermidis Biofilm Formation

OpenAIRE

R Magetsari; P Dewo; BK Saputro; Z Lanodiyu

2014-01-01

S. Epidermidis is among the most frequently isolated microorganisms found in -infection related to implanted devices and the formation of biofilm will be more resistantcompared to the planktonic form. This study was carried out determine the effect of coating on stainless steel orthopaedic implants surfaces with cinnamon oil and chitosan as bioadhesive to prevent biofilms formation of S. Epidermidis.The rod shaped stainless steel 316 L orthopaedic implant with 5 mm diameters was coated 2 t...

Some experiments on the primary electron acceptor in reaction centres from Rhodopseudomanas sphaeroides

Energy Technology Data Exchange (ETDEWEB)

Wraight, C A; Cogdell, R J; Clayton, R K

1975-01-01

The bacterial reaction center absorbance change at 450 nm (A-450), assigned to an anionic semiquinone, has been suggested as a candidate for the reduced form of the primary electron acceptor in bacterial photosynthesis. In reaction centers of Rhodopseudomonas sphaeroides we have found kinetic discrepancies between the decay of A-450 and the recovery of photochemical competence. In addition, no proton uptake is measurable on the first turnover, although subsequent ones elicit one proton bound per electron. These results are taken to indicate that the acceptor reaction after a long dark period may be different for the first turnover than for subsequent ones. It is suggested that A-450 is still a likely candidate for the acceptor function but that in reaction centers, additional quinone may act as an adventitious primary acceptor when the ''true'' primary acceptor is reduced. Alternatively, the primary acceptor may act in a ''ping-pong'' fashion with respect to subsequent photoelectrons.

Professor Michael Levitt

Directory of Open Access Journals (Sweden)

Gemma-Louise Davies

2015-10-01

Full Text Available Professor Michael Levitt (Stanford University, USA won the 2013 Nobel Prize in Chemistry for the development of multiscale models for complex chemical systems—computational tools which can calculate the course of chemical reactions. Professor Levitt was born in Pretoria, South Africa; he came to the UK on a summer vacation aged 16, where he decided to stay and study for his A‑levels. His interest in the physics of living systems drove him to study biophysics at King’s College London, before securing a PhD position at the Laboratory of Molecular Biology in Cambridge. In the interim year between his degree and beginning his PhD, Professor Levitt worked at the Weizmann Institute of Science in Israel, where he met his future wife. They married later that year and moved to Cambridge, where their three children were born. After completing his PhD, he spent time working in Israel, Cambridge, the Salk Institute and Stanford (both California. Since 1986, he has split his time between Israel and California. Outside of science, he is a keen hiker and he is well-known to have attended the eclectic ‘Burning Man’ Festival in California.[1] Professor Levitt visited the University of Warwick to speak at the Computational Molecular Science Annual Conference in March 2015. In this interview, Dr Gemma-Louise Davies, an Institute of Advanced Study Global Research Fellow, spoke to Professor Levitt about the importance of Interdisciplinarity in his field, role models in Academia, and his plans for the future. Image: Professor Michael Levitt (left with Dr Scott Habershon (right, organiser of the 2015 Computational Molecular Science Annual Conference during his visit to the University of Warwick in March 2015. [1] ‘Burning Man’ is a unique annual festival dedicated to community, art, music, self-expression and self-reliance. Tens of thousands of people flock to this temporary metropolis built in the Californian desert.

Part I. Synthesis and characterization of donor-pi-acceptor compounds with pentadienyl-bridged indoline and tetrahydroquinoline donors and aldehyde and thiobarbituric acid acceptors Part II. Longitudinal study comparing online versus face-to-face course delivery in introductory chemistry

Science.gov (United States)

Greco, Patrick F.

Part I. The design and development of organic second-order nonlinear optical (NLO) materials have attracted much interest due to their applications in optoelectronic devices and modern communications technology. Donor-pi-acceptor compounds, D-(CH=CH)n-A, often exhibit hyperpolarizability that results in laser frequency doubling (second harmonic generation) and spectroscopic solvatochromism. To study the effect of donor amine geometry upon properties associated with second-order NLO behavior in simple donor-pi-acceptor compounds, equilibrium geometries and hyperpolarizabilities (beta) for donor-acceptor polyenes with amine donors were calculated at several levels of computational theory. Two new molecules with donors that only differ by one methylene group were chosen for comparison. Thus, 5-(N-methylindolin-5-yl)-2, 4-pentadienal (1a) and 5-(N-methyl-2, 3, 4-trihydroquinolin-6-yl)-2, 4-pentadienal (2a) were synthesized in two steps from starting materials described in the literature. These aldehydes were converted into stronger acceptors in one step to give diethylthiobarbituric acid derivatives 1c and 2c, as well as tricyanofuran derivatives 1d and 2d. Positive UV solvatochromism was observed in all three derivatives. NMR solvatochromism was most pronounced in 1c, and 2c vs. 1a and 2a as measured by changes in chemical shifts. Additionally, coupling constants showed more conjugation in 1c and 2c, where 1a and 2a showed less conjugation. Finally, differential scanning calorimetry and thermal gravimetric analysis were used to compare decomposition and melting temperatures of these compounds to determine their stability. Aldehydes, 1a and 2a had distinct melting points, while the 1c, 2c, 1d, and 2d derivatives decomposed at temperatures above 150 °C. Part II. This longitudinal study focused on an introductory chemistry course taught using two different modes of delivery: online and face-to-face (FtF). The sections of the course using the different delivery modes

Non-fullerene acceptors for organic solar cells

Science.gov (United States)

Yan, Cenqi; Barlow, Stephen; Wang, Zhaohui; Yan, He; Jen, Alex K.-Y.; Marder, Seth R.; Zhan, Xiaowei

2018-03-01

Non-fullerene acceptors (NFAs) are currently a major focus of research in the development of bulk-heterojunction organic solar cells (OSCs). In contrast to the widely used fullerene acceptors (FAs), the optical properties and electronic energy levels of NFAs can be readily tuned. NFA-based OSCs can also achieve greater thermal stability and photochemical stability, as well as longer device lifetimes, than their FA-based counterparts. Historically, the performance of NFA OSCs has lagged behind that of fullerene devices. However, recent developments have led to a rapid increase in power conversion efficiencies for NFA OSCs, with values now exceeding 13%, demonstrating the viability of using NFAs to replace FAs in next-generation high-performance OSCs. This Review discusses the important work that has led to this remarkable progress, focusing on the two most promising NFA classes to date: rylene diimide-based materials and materials based on fused aromatic cores with strong electron-accepting end groups. The key structure-property relationships, donor-acceptor matching criteria and aspects of device physics are discussed. Finally, we consider the remaining challenges and promising future directions for the NFA OSCs field.

SuchThatCast Episode 6: Michael Boylan

NARCIS (Netherlands)

Soraker, Johnny

2012-01-01

Michael Boylan is the John J. McDonnell jr chair in Ethics, and professor and chair of the philosophy department at Marymount University in Arlington, Virginia. In addition to being a poet and novelist, he has written more than 100 published articles and 25 books primarily in ethics, social and

Double Michael Addition Reaction of Bischalcone under Ultrasound

Institute of Scientific and Technical Information of China (English)

LI,Ji-Tai; XU,Wen-Zhi; CHEN,Guo-Feng; LI,Tong-Shuang

2004-01-01

@@ The Michael addition of 1,5-diaryl-1,4-pentadien-3-ones with active methylene compounds has been the subjects of many investigations. Ultrasound has increasingly been used in organic synthesis in the last three decades. Compared with traditional methods, this method is more convenient and easily controlled. A large number of organic reactions can be carried out in higher yield, shorter reaction time or milder conditions under ultrasonic irradiation. KF/Al2O3 as a useful solid supported catalyst has received considerable attention because of their high level of chemoselectivity and environmental compatibility as well as simplicity of operation and their ready availability at low cost. Herein we report the double Michael addition of dibenzalacetone with active methlene compounds such as dimethyl malonate, diethyl malonate,methyl cyanoacetate and ethyl cyanoacetate catalyzed by KF/Al2O3 under ultrasound irradiation.

Michael Frayn visits CERN

CERN Multimedia

2007-01-01

Award-winning playwright and novelist Michael Frayn gave a guest lecture in the main auditorium at CERN on Friday 15 March about his new book The Human Touch: Our Part in the Creation of the Universe. The lecture focused on cosmology and philosophy and the limitations that language places on our ability to understand the creation of a universe in which we seem to play such a small part. In addition to his novels and plays, which include Copenhagen, a play about the 1941 meeting between German physicist Werner Heisenberg and Danish physicist Niels Bohr, Frayn has translated several works from Russian, including plays by Chekhov and Tolstoy.

Between Irish National Cinema and Hollywood: Neil Jordan’s Michael Collins

Directory of Open Access Journals (Sweden)

Raita Merivirta-Chakrabarti

2007-03-01

Full Text Available When Neil Jordan’s film Michael Collins was released in 1996, it was seen by some as a Hollywood epic, by others as a great national film. I would argue that Michael Collins combines these two traditions and occupies a space between Irish national cinema and Hollywood. The subject matter, the creative talent and the locations were Irish and the film was produced by using the Irish filmmaking infrastructure and the Irish government’s support mechanisms, but it was largely financed and distributed by a Hollywood studio. Also, to make it more appealing especially globally, but probably also locally (since Hollywood is now the international standard, it makes use of Hollywood conventions, making it accessible to international audiences as well. Despite the Hollywood mode, the fact remains that Michael Collins is a national film text, and Jordan does not make too many concessions to the non-Irish audiences.

Reframing Michael Scott: Exploring Inappropriate Workplace Communication

Science.gov (United States)

Schaefer, Zachary A.

2010-01-01

Individuals who work in professional settings interact with others who may exhibit a variety of cultural beliefs and decision-making approaches. Page (2007) argues that cognitive diversity (i.e., how people approach and attempt to solve problems) is a vital asset in effective organizations. Michael Scott, who portrays the inept main character on…

COMPARISON OF ACCEPTOR PROPERTIES FOR INTERACTION ...

African Journals Online (AJOL)

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determined by UV-Vis titration method for the adducts. Surprisingly, the ... Interaction of. TCNE and DDQ as π-acceptors with hydrocarbon donors such as cycloalkanes, alkenes, ... obtained from a Shimadzu GC-MS model QP5050 instrument.

Michael Moore kaevati kohtusse pettuse eest / Mari Rebane

Index Scriptorium Estoniae

Rebane, Mari

2006-01-01

Dokumentaalfilm "9/11 Fahrenheiti" ("Fahrenheit 9/11") : režissöör Michael Moore : USA 2004. Iraagi sõja invaliidistunud veteran andis režissööri kohtusse teda kujutavate flmikaadrite loata ja tenentsliku kasutamise pärast

Simulation study on the effects of chemical structure and molecular size on the acceptor strength in poly(3-hexylthiophene)-based copolymer with alternating donor and acceptor for photovoltaic applications

Science.gov (United States)

Rassamesard, Areefen; Pengpan, Teparksorn

2017-02-01

This research assessed the effects of various chemical structures and molecular sizes on the simulated geometric parameters, electron structures, and spectroscopic properties of single-chain complex alternating donor-acceptor (D-A) monomers and copolymers that are intended for use as photoactive layer in a polymer solar cell by using Kohn-Sham density functional theory with B3LYP exchange-correlation functional. The 3-hexylthiophene (3HT) was selected for electron donor, while eight chemicals, namely thiazole (Z), thiadiazole (D), thienopyrazine (TP), thienothiadiazole (TD), benzothiadiazole (BT), thiadiazolothieno-pyrazine (TPD), oxadiazole (OXD) and 5-diphenyl-1,2,4-triazole (TAZ), were employed as electron acceptor functional groups. The torsional angle, bridge bond length, intramolecular charge transfer, energy levels, and molecular orbitals were analyzed. The simulation results reveal that the geometry and electron structure of donor-acceptor monomer and copolymer are significantly impacted by heterocyclic rings, heteroatoms, fused rings, degree of steric hindrance and coplanarity of the acceptor molecular structure. Planar conformation was obtained from the D copolymer, and a pseudo-planar structure with the TD copolymer. The TAZ acceptor exhibited strong steric hindrance due to its bulky structure and non-planarity of its structure. An analysis of the electron structures indicated that the degree of intramolecular electron-withdrawing capability had the rank order TAZ  gaps of TD as well as TPD copolymer indicate that these two copolymers can be used in transparent conducting materials. The copolymer based on BT acceptor exhibited good intramolecular charge transfer and absorbed at 656 nm wavelength which is close to the maximum flux of solar spectrum. Hence, the BT acceptor functional group provides a compromise in the characteristics of a donor-acceptor copolymer, useful in a polymeric candidate material for the photoactive layer in a polymer solar

A survey of acceptor dopants for β-Ga2O3

Science.gov (United States)

Lyons, John L.

2018-05-01

With a wide band gap, high critical breakdown voltage and commercially available substrates, Ga2O3 is a promising material for next-generation power electronics. Like most wide-band-gap semiconductors, obtaining better control over its electrical conductivity is critically important, but has proven difficult to achieve. Although efficient p-type doping in Ga2O3 is not expected, since theory and experiment indicate the self-trapping of holes, the full development of this material will require a better understanding of acceptor dopants. Here the properties of group 2, group 5 and group 12 acceptor impurities in β-Ga2O3 are explored using hybrid density functional calculations. All impurities are found to exhibit acceptor transition levels above 1.3 eV. After examining formation energies as a function of chemical potential, Mg (followed closely by Be) is determined to be the most stable acceptor species.

The effects of cinnamon on glycemic indexes and insulin resistance in adult male diabetic rats with streptozotocin

OpenAIRE

SEbrahim Hosseini; STaereh Shojaei; SAli Hosseini

2015-01-01

Background: Diabetes is a common disease that for its treatment and control different methods are recommended such as the use of natural remedies and lifestyle modification. Since the use of herbal medicines have less side effects than many chemical drugs, hence, this study aimed to investigate the effect of cinnamon extract on blood glucose, insulin and insulin resistance in diabetic rats with streptozotocin. Materials and Methods: This experimental study was conducted on 40 adult male rats,...

Synthesis and optoelectronic characterization of some triphenylamine-based compounds containing strong acceptor substituents

Energy Technology Data Exchange (ETDEWEB)

Grigoras, Mircea, E-mail: grim@icmpp.ro; Ivan, Teofilia; Vacareanu, Loredana; Catargiu, Ana Maria; Tigoianu, Radu

2014-09-15

Three novel triphenylamine-based compounds containing strong electron acceptor groups have been synthesized and their comparative photophysical properties are presented. These compounds were obtained by a two-step method: (i) triphenylamine compounds with one, two and three phenylacetylene arms were synthesized by Sonogashira reaction between iodine-substituted triphenylamines and phenylacetylene, followed by (ii) post-modification of these electron-rich alkynes by addition of the strong electron acceptor, tetracyanoethylene. Characterization of all oligomers was made by FTIR, {sup 1}H-NMR, UV–vis and fluorescence spectroscopy. A batochromic shifting of the UV and photoluminescence maxima was observed with the increase of the acceptor group number. The electrochemical behavior was studied by cyclic voltammetry. The cyclic voltammograms have evidenced that triphenylamine-phenylacetylene compounds undergo only oxidation processes while compounds modified with tetracyanoethylene show both oxidation and reduction peaks associated with donor and acceptor groups, respectively. The donor–acceptor compounds coordinate metal ions (i.e., Hg{sup 2+} and Sn{sup 2+}) by cyano groups resulting in the decreasing of charge transfer band intensity, and they can be used as chemosensors. - Highlights: • Three triphenylamine-based ethynylene compounds were prepared by Sonogashira reaction. • Post-modification of ethynylene linkages by tetracyanethylene cycloaddition and retroconversion led to donor–acceptor compounds. • Photophysical properties of donor–acceptor oligomers were studied in different solvents.

Natural Cinnamic Acids, Synthetic Derivatives and Hybrids with Antimicrobial Activity

Directory of Open Access Journals (Sweden)

Juan David Guzman

2014-11-01

Full Text Available Antimicrobial natural preparations involving cinnamon, storax and propolis have been long used topically for treating infections. Cinnamic acids and related molecules are partly responsible for the therapeutic effects observed in these preparations. Most of the cinnamic acids, their esters, amides, aldehydes and alcohols, show significant growth inhibition against one or several bacterial and fungal species. Of particular interest is the potent antitubercular activity observed for some of these cinnamic derivatives, which may be amenable as future drugs for treating tuberculosis. This review intends to summarize the literature data on the antimicrobial activity of the natural cinnamic acids and related derivatives. In addition, selected hybrids between cinnamic acids and biologically active scaffolds with antimicrobial activity were also included. A comprehensive literature search was performed collating the minimum inhibitory concentration (MIC of each cinnamic acid or derivative against the reported microorganisms. The MIC data allows the relative comparison between series of molecules and the derivation of structure-activity relationships.

Michael Haneke film Euroopa parim / M. T.

Index Scriptorium Estoniae

M. T.

2005-01-01

IX PÖFFil linastuv Michael Haneke film "Varjatud" ("Cache") võitis laupäeval mitu Euroopa Filmiakadeemia auhinda, selhulgas parima filmi, parima lavastaja, parima meesnäitleja (Daniel Auteuil) ja FIPRESCI auhinna. Parim naisnäitleja - Julia Jentsch ("Sophie Scholli viimased päevad"), operaator - Franz Lustig ("Don't Come Knocking"), stsenaarium - Hany Abu-Assad, Bero Beyer ("Kohe paradiisi")

Donor assists acceptor binding and catalysis of human α1,6-fucosyltransferase.

Science.gov (United States)

Kötzler, Miriam P; Blank, Simon; Bantleon, Frank I; Wienke, Martin; Spillner, Edzard; Meyer, Bernd

2013-08-16

α1,6-Core-fucosyltransferase (FUT8) is a vital enzyme in mammalian physiological and pathophysiological processes such as tumorigenesis and progress of, among others, non-small cell lung cancer and colon carcinoma. It was also shown that therapeutic antibodies have a dramatically higher efficacy if the α1,6-fucosyl residue is absent. However, specific and potent inhibitors for FUT8 and related enzymes are lacking. Hence, it is crucial to elucidate the structural basis of acceptor binding and the catalytic mechanism. We present here the first structural model of FUT8 in complex with its acceptor and donor molecules. An unusually large acceptor, i.e., a hexasaccharide from the core of N-glycans, is required as minimal structure. Acceptor substrate binding of FUT8 is being dissected experimentally by STD NMR and SPR and theoretically by molecular dynamics simulations. The acceptor binding site forms an unusually large and shallow binding site. Binding of the acceptor to the enzyme is much faster and stronger if the donor is present. This is due to strong hydrogen bonding between O6 of the proximal N-acetylglucosamine and an oxygen atom of the β-phosphate of GDP-fucose. Therefore, we propose an ordered Bi Bi mechanism for FUT8 where the donor molecule binds first. No specific amino acid is present that could act as base during catalysis. Our results indicate a donor-assisted mechanism, where an oxygen of the β-phosphate deprotonates the acceptor. Knowledge of the mechanism of FUT8 is now being used for rational design of targeted inhibitors to address metastasis and prognosis of carcinomas.

Development of an enzyme-linked immunosorbent assay-based method for measuring galactosyltransferase activity using a synthetic glycopolymer acceptor substrate.

Science.gov (United States)

Oubihi, M; Kitajima, K; Kobayashi, K; Adachi, T; Aoki, N; Matsuda, T

1998-03-15

A lectin-assisted enzyme-linked immunosorbent assay (ELISA)-based method using a synthetic glycopolymer as an acceptor substrate was developed for measuring beta 1,4-galactosyltransferase (GalT) activity. A polyacrylamide derivative having a beta-linked N-acetylglucosamine (GlcNAc beta) moiety on each monomeric unit was synthesized chemically and immobilized on a polystyrene microtiter plate as an acceptor substrate for GalT. After the plate was incubated with bovine GalT, the enzyme reaction product, beta-linked Gal residue on the polyacrylamide-bound GlcNAc residue, was detected by using Ricinus communis agglutinin 1 (RCA1), rabbit anti-RCA1 antibody, and a peroxidase-labeled anti-rabbit IgG. The lowest GalT concentration detectable by this method was about 0.5 mU/ml, which is comparable to those by the previously reported ELISA-based assays. The unique property of the glycopolymer, PAP(GlcNAc beta), of binding noncovalently but tightly to the polystyrene microtiter plate allowed the use of this acceptor substrate for the GalT activity measurement even in the presence of 1% Triton CF-54 and X-100. Our system was successfully applied to assess GalT activity in milk of various mammals.

Nano-scale control of energy transfer in the system 'donor-acceptor'

International Nuclear Information System (INIS)

Malyukin, Yu.V.; Yefimova, S.L.; Lebedenko, A.N.; Sorokin, A.V.; Borovoy, I.A.

2005-01-01

Fluorescence resonance energy transfer (FRET) in a cascade scheme between three amphiphilic dyes 3,3'-dioctadecyloxacarbocyanine perchlorate (DiOC 18 (3), donor), 1,1'-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine perchlorate (DiIC 18 (3), acceptor/donor) and 1,1'-dioctadecyl-3,3,3',3'-tetramethylindodicarbocyanine perchlorate (DiIC 18 (5), acceptor) has been investigated at low dye concentration (10 -5 mol/l) in water-micellar solutions due to a forced assembling of dyes in nanoscale volume. The experimental data have revealed that sodium dodecyl sulfate (SDS) micelles solubilize dye molecules such that their hydrophilic heads are in contact with water, while hydrophobic tails are embedded into the hydrocarbon core of the micelle. FRET efficiency has been found to depend on the concentration of dyes in micelles and the most effective when each SDS micelle contains 1 donor (DiOC 18 (3)), 2 acceptor/donor (DiIC 18 (3)) and 4 acceptor (DiIC 18 (5)) molecules

Acceptors in cadmium telluride. Identification and electronic structure

International Nuclear Information System (INIS)

Molva, E.

1983-11-01

It is shown that electronic properties of CdTe are determined by impurities more than by intrinsic defects like vacancies or interstitials in Cd or Te contrary to classical theories. These results are based on annealing, diffusion, implantation and electron irradiation at 4 K. Centers appearing in treated samples are accurately identified by photoluminescence, cathodoluminescence infra-red absorption, electrical measurements and magneto-optic properties. Acceptors identified are Li, Na, Cu, Ag and Au impurities in Cd and N, P and As in Te. Energy levels of all acceptors and fine structure of excitons are determined [fr

Coumarin amide derivatives as fluorescence chemosensors for cyanide anions

Energy Technology Data Exchange (ETDEWEB)

Wu, Qianqian [School of Material Science and Engineering, Shandong Provincial Key Laboratory of Preparation and Measurement of Building Materials, University of Jinan, Jinan 250022, Shandong (China); Liu, Zhiqiang [State Key Laboratory of Crystal Materials, Shandong University, Jinan 250100, Shandong (China); Cao, Duxia, E-mail: duxiacao@ujn.edu.cn [School of Material Science and Engineering, Shandong Provincial Key Laboratory of Preparation and Measurement of Building Materials, University of Jinan, Jinan 250022, Shandong (China); Guan, Ruifang, E-mail: mse_guanrf@ujn.edu.cn [School of Material Science and Engineering, Shandong Provincial Key Laboratory of Preparation and Measurement of Building Materials, University of Jinan, Jinan 250022, Shandong (China); Wang, Kangnan; Shan, Yanyan; Xu, Yongxiao; Ma, Lin [School of Material Science and Engineering, Shandong Provincial Key Laboratory of Preparation and Measurement of Building Materials, University of Jinan, Jinan 250022, Shandong (China)

2015-07-01

Four coumarin amide derivatives with 4-methyl coumarin or pyrene as terminal group have been synthesized. Their photophysical properties and recognition properties for cyanide anions have been examined. The results indicate that the compounds can recognize cyanide anions with obvious absorption and fluorescence spectra change, at the same time, obvious color and fluorescence change can be observed by naked eye. The in situ hydrogen nuclear magnetic resonance spectra and photophysical properties change confirm that Michael additions between the chemosensors and cyanide anions take place at the 4-position of coumarin. - Highlights: • Four coumarin amide derivatives with 4-methyl coumarin or pyrene as terminal group were synthesized. • The compounds can recognize cyanide anions with obvious absorption and fluorescence spectra change. • Michael additions between the chemosensors and cyanide anions take place at the 4-position of coumarin.

Perylene-Diimide Based Donor-Acceptor-Donor Type Small-Molecule Acceptors for Solution-Processable Organic Solar Cells

Science.gov (United States)

Ganesamoorthy, Ramasamy; Vijayaraghavan, Rajagopalan; Sakthivel, Pachagounder

2017-12-01

Development of nonfullerene acceptors plays an important role in the commercial availability of plastic solar cells. We report herein synthesis of bay-substituted donor-acceptor-donor (D-A-D)-type perylene diimide (PDI)-based small molecules (SM-1 to SM-4) by Suzuki coupling method and their use as acceptors in bulk heterojunction organic solar cells (BHJ-OSCs) with poly(3-hexylthiophene) (P3HT) polymer donor. We varied the number of electron-rich thiophene units and the solubilizing side chains and also evaluated the optical and electrochemical properties of the small molecules. The synthesized small molecules were confirmed by Fourier-transform infrared (FT-IR) spectroscopy, nuclear magnetic resonance (NMR) spectroscopy, and high-resolution mass spectroscopy (HR-MS). The small molecules showed extensive and strong absorption in the ultraviolet-visible (UV-Vis) region up to 750 nm, with bandgap (E_{{g}}^{{opt}} ) reduced below use as electron-accepting materials. The small molecules showed good thermal stability up to 300°C. BHJ-OSCs with SM-1 and P3HT polymer donor showed maximum power conversion efficiency (PCE) of 0.19% with V oc of 0.30 V, J sc of 1.72 mA cm-2, and fill factor (FF) of 37%. The PCE decreased with the number of thiophene units. The PCE of SM-2 was lower than that of SM-1. This difference in PCE can be explained by the higher aggregation tendency of the bithiophene compared with the thiophene unit. Introduction of the solubilizing group in the bay position increased the aggregation property, leading to much lower PCE than for the small molecules without solubilizing group.

Dye-Incorporated Polynaphthalenediimide Acceptor for Additive-Free High-Performance All-Polymer Solar Cells.

Science.gov (United States)

Chen, Dong; Yao, Jia; Chen, Lie; Yin, Jingping; Lv, Ruizhi; Huang, Bin; Liu, Siqi; Zhang, Zhi-Guo; Yang, Chunhe; Chen, Yiwang; Li, Yongfang

2018-04-16

All-polymer solar cells (all-PSCs) can offer unique advantages for applications in flexible devices, and naphthalene diimide (NDI)-based polymer acceptors are the widely used polymer acceptors. However, their power conversion efficiency (PCE) still lags behind that of state-of-the-art polymer solar cells, due to low light absorption, suboptimal energy levels and the strong aggregation of the NDI-based polymer acceptor. Herein, a rhodanine-based dye molecule was introduced into the NDI-based polymer acceptor by simple random copolymerization and showed an improved light absorption coefficient, an up-shifted lowest unoccupied molecular orbital level and reduced crystallization. Consequently, additive-free all-PSCs demonstrated a high PCE of 8.13 %, which is one of the highest performance characteristics reported for all-PSCs to date. These results indicate that incorporating a dye into the n-type polymer gives insight into the precise design of high-performance polymer acceptors for all-PSCs. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Brändi näkyy musiikkivideossa : Esimerkkitapaus Michael Jackson

OpenAIRE

Kontinen, Noora

2016-01-01

Tutkin opinnäytetyössäni brändin ja musiikkivideon suhdetta toisiinsa. Työssä käsitellään lyhyesti myös tähteyttä. Esittelen ensin vähän historiaa ja peruskäsitteitä, minkä jälkeen käytän Michael Jacksonin Billie Jean -musiikkivideota esimerkkinä tutkiessani Michael Jacksonin brändiä. Teoksessa käytetään lähdeaineistoa sekä omaa analyysia. Keskityn tarkastelemaan musiikkivideoita, ja niihin liittyviä sisältöjä yleisesti, ei niinkään teknisesti. Toivon, että työstäni on apua jollekin,...

Lewis acid catalyzed [3 + 2] annulation of ketenimines with donor-acceptor cyclopropanes: an approach to 2-alkylidenepyrrolidine derivatives.

Science.gov (United States)

Alajarin, Mateo; Egea, Adrian; Orenes, Raul-Angel; Vidal, Angel

2016-11-02

The [3 + 2] annulation reaction of C,C,N-trisubstituted ketenimines with donor-acceptor cyclopropanes bearing aryl, styryl and vinyl substituents at the C2 position, triggered by the Lewis acid Sc(OTf) 3 , supplies highly substituted pyrrolidines. Activated cyclopropanes fused to naphthalene and [1]benzopyrane nuclei are also suitable substrates in similar transformations, yielding partially saturated benz[g]indoles and [1]benzopyran[4,3-b]pyrroles. An intramolecular version of this ketenimine/cyclopropane [3 + 2] annulation has also been developed leading to the pyrrolo[2,1-a]isoindole framework.

Synthesis, characterization of bay-substituted perylene diimide based D-A-D type small molecules and their applications as a non-fullerene electron acceptor in polymer solar cells

Directory of Open Access Journals (Sweden)

Ramasamy Ganesamoorthy

2018-03-01

Full Text Available We report a series of bay substituted perylene diimide based donor-acceptor-donor (D-A-D type small molecule acceptor derivatives such as S-I, S-II, S-III and S-IV for small molecule based organic solar cell (SM-OSC applications. The electron rich thiophene derivatives such as thiophene, 2-hexylthiophene, 2,2′-bithiophene, and 5-hexyl-2,2′-bithiophene were used as a donor (D, and perylene diimide was used as an acceptor (A. The synthesized small molecules were confirmed by FT-IR, NMR, and HR-MS. The small molecules showed wide and strong absorption in the UV-vis region up to 750 nm, which reduced the optical band gap to <2 eV. The calculated highest occupied molecular orbital (HOMO and the lowest unoccupied molecular orbital (LUMO were comparable with those of the PC61BM. Scanning electron microscope (SEM studies confirmed the aggregation of the small molecules, S-I to S-IV. Small molecules showed thermal stability up to 300 °C. In bulk heterojunction organic solar cells (BHJ-OSCs, the S-I based device showed a maximum power conversion efficiency (PCE of 0.12% with P3HT polymer donor. The PCE was declined with respect to the number of thiophene units and the flexible alkyl chain in the bay position. Keywords: Perylene diimide, Donor–acceptor, Small molecule, Non-fullerene, Suzuki coupling

Michael Goodsite gæsteprofessor på Thunderbird School of Global Management

DEFF Research Database (Denmark)

Pedersen, Jens Christian

2010-01-01

Professor Michael Goodsite er blevet udnævnt til "Visiting Professor of Global Processes and Senior Research Fellow in Climate Strategy" ved Thunderbird School of Global Management, som har verdens højst rangerede MBA uddannelse inden for international handel.......Professor Michael Goodsite er blevet udnævnt til "Visiting Professor of Global Processes and Senior Research Fellow in Climate Strategy" ved Thunderbird School of Global Management, som har verdens højst rangerede MBA uddannelse inden for international handel....

Correspondence of Michael Faraday, v.5 1855-1860

CERN Document Server

Faraday, Michael

2008-01-01

This volume includes 70% of previously unpublished letters of Michael Farday spanning half of the 1850s and most of 1860. Topics include Faraday's work on regelation, the transmission of light through gold and his appointment by Emperor Napoleon III to be a Commander of the Legion of Honour.

Syntheses of planar 1,5,2,4,6,8-dithiotetrazocine derivatives and thermodynamic study on intermolecular charge transfer for developing efficient organic solar cell

Energy Technology Data Exchange (ETDEWEB)

Zhang, Chao-Zhi, E-mail: zhangchaozhi@nuist.edu.cn [Department of Chemistry, Nanjing University of Information Science & Technology, Nanjing 210044 (China); Shen, Dan [Department of Chemistry, Nanjing University of Information Science & Technology, Nanjing 210044 (China); Yuan, Yang [Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control, Nanjing University of Information Science & Technology, Nanjing 210044 (China); Song, Ming-Xia; Li, Shi-Juan [Department of Chemistry, Nanjing University of Information Science & Technology, Nanjing 210044 (China); Cao, Hui, E-mail: yccaoh@hotmail.com [Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control, Nanjing University of Information Science & Technology, Nanjing 210044 (China)

2016-07-01

A series of planar 1,5,2,4,6,8-dithiotetrazocine derivatives were synthesized for study on charge transfer at donor/acceptor interface. The fluorescence quenching spectra, and the highest occupied molecular orbital (−6.10 ∼ −6.25 eV) and the lowest unoccupied molecular orbital (−3.45 ∼ −3.58 eV) energy levels of these 1,5,2,4,6,8-dithiotetrazocine derivatives show that they would be potential acceptor materials. Based on theoretical calculations, thermodynamic study on charge transfer at donor/acceptor interface was carried out. The results of experiments and theoretical calculations show that the electrons could transfer spontaneously from poly(3-hexylthiophene) to these acceptors. The percentages of fluorescence quenching increase with negative Gibbs free energy values increasing in the charge transfer procedures. Therefore, short circuit current values of organic solar cells would increase with the Gibbs free energy values increasing. This paper suggests a useful way for developing efficient organic solar cells. - Highlights: • Syntheses of planar 1,5,2,4,6,8-dithiotetrazocine derivatives for develop effective acceptor. • Electrons at excited state in P3HT could transfer spontaneously to these acceptors. • Thermodynamic study on charge transfer at donor/acceptor interface. • Short circuit currents would be predicted by Gibbs free energy in procedure of charge transfer.

Michael Jackson antes del caos

OpenAIRE

Juan Luciano Nieves

2015-01-01

Michael Jackson es un buen ejemplo de cómo utilizar las relaciones públicas para realizar o manipular la imagen de un producto a través de los medios de comunicación. Este ensayo pretende analizar los eventos que tuvieron lugar antes de que el cantante fuera acusado de abuso sexual contra un menor. Dichos eventos formaron parte de un plan muy bien delineado para disminuir los efectos de la inminente crisis que se acercaba. Este trabajo combina la crítica retórica de temas de fantasía con teor...

Exciplex elimination in an organic light-emitting diode based on a fluorene derivative by inserting 4,4'-N,N'-dicarbazole-biphenylinto donor/acceptor interface

International Nuclear Information System (INIS)

Wei, Zhang; Jun-Sheng, Yu; Jiang, Huang; Ya-Dong, Jiang; Qing, Zhang; Kang-Li, Cao

2010-01-01

Organic light-emitting diodes (OLEDs) composed of a novel fluorene derivative of 2,3-bis(9,9-dihexyl-9H-fluoren-2-yl)-6,7-difluoroquinoxaline (F2Py) were fabricated, and exciplex emission was observed in the device. To depress the exciplex in an OLED for pure colour light emission, 4, 4'-N,N'-dicarbazole-biphenyl (CBP) was inserted as a separator at the donor/acceptor interface. It was found that the device without the CBP layer emitted a green light peaking at 542 nm from the exciplex and a shoulder peak about 430 nm from F2Py. In contrast, the OLED with CBP layer emitted only a blue light peak at about 432 nm from F2Py. Device efficiencies were calculated by a simulative mode in an injection controlled type mechanism, and the results showed that exciplexes yield much lower quantum efficiency than excitons. The device with CBP has a higher power efficiency as no exciplex was present. (condensed matter: electronic structure, electrical, magnetic, and optical properties)

Donor and Acceptor Polymers for Bulk Hetero Junction Solar Cell and Photodetector Applications

KAUST Repository

Cruciani, Federico

2018-04-01

Bulk heterojunction (BHJ) devices represent a very versatile family of organic cells for both the fields of solar energy conversion and photodetection. Organic photovoltaics (OPV) are an attractive alternative to their silicon-based counterparts because of their potential for low-cost roll-to-roll printing, and their intended application in light-weight mechanically conformable devices and in window-type semi-transparent PV modules. Of all proposed OPV candidates, polymer donor with different absorption range are especially promising when used in conjunction with complementary absorbing acceptor materials, like fullerene derivatives (PCBM), conjugated molecules or polymers, achieving nowadays power conversion efficiencies (PCEs) in the range of 10-13% and being a step closer to practical applications. Among the photodetectors (PD), low band gap polymer blended with PCBM decked out the attention, given their extraordinary range of detection from UV to IR and high detectivity values reached so far, compared to the inorganic devices. Since the research has been focused on the enhancement of those numbers for an effective commercialization of organic cells, the topic of the following thesis has been centered on the synthesis of different polymer structures with diverse absorption ranges, used as donor or acceptor, with emphasis on performance in various BHJ devices either for solar cells and photodetectors. In the first part, two new wide band gap polymers, used as donor material in BHJ devices blended with fullerene and small molecule acceptors, are presented. The PBDT_2FT and PBDTT_2FT have shown nice efficiencies from 7% to 9.8%. The device results are implemented with a morphology study and a specific application in a semi-transparent tandem device, reaching a record PCE of 5.4% for average level of transparency of 48%. In another section two new low band gap polymers (Eopt~ 1.26 eV) named DTP_2FBT and (Eopt~ 1.1 eV) named BDTT_BTQ are presented. While the DTP

Conduction electrons in acceptor-doped GaAs/GaAlAs heterostructures: a review

International Nuclear Information System (INIS)

Zawadzki, Wlodek; Raymond, Andre; Kubisa, Maciej

2016-01-01

We review magneto-optical and magneto-transport effects in GaAs/GaAlAs heterostructures doped in GaAlAs barriers with donors, providing two-dimensional (2D) electron gas (2DEG) in GaAs quantum wells (QWS), and additionally doped with smaller amounts of acceptors (mostly Be atoms) in the vicinity of 2DEG. One may also deal with residual acceptors (mostly C atoms). The behavior of such systems in the presence of a magnetic field differs appreciably from those doped in the vicinity of 2DEG with donors. Three subjects related to the acceptor-doped heterostructures are considered. First is the problem of bound states of conduction electrons confined to the vicinity of negatively charged acceptors by the joint effect of a QW and an external magnetic field parallel to the growth direction. A variational theory of such states is presented, demonstrating that an electron turning around a repulsive center has discrete energies above the corresponding Landau levels. Experimental evidence for the discrete electron energies comes from the work on interband photo-magneto-luminescence, intraband cyclotron resonance and quantum magneto-transport (the Quantum Hall and Shubnikov–de Haas effects). An electron rain-down effect at weak electric fields and a boil-off effect at strong electric fields are introduced. It is demonstrated, both theoretically and experimentally, that a negatively charged acceptor can localize more than one electron. The second subject describes experiment and theory of asymmetric quantized Hall and Shubnikov–de Haas plateaus in acceptor-doped GaAs/GaAlAs heterostructures. It is shown that the main features of the plateau asymmetry can be attributed to asymmetric density of Landau states in the presence of acceptors. However, at high magnetic fields, the rain-down effect is also at work. The third subject deals with the so-called disorder modes (DMs) in the cyclotron resonance of conduction electrons. The DMs originate from random distributions of

Eesti luksushotellide ristiisa / Michael Stenner ; interv. Malle Koido

Index Scriptorium Estoniae

Stenner, Michael

2007-01-01

Eesti tipphotelle 1997. aastast juhtinud sakslane, praegu hotellide Kolm Õde ja Telegraaf juht räägib Eesti ja Saksamaa erinevustest, Eesti hotelliärist, teeninduskultuurist ja personalist. Lisa: Kes on Michael Stenner ning kuidas ta Eestisse sattus? Ilmunud ka: Linnaleht : Pärnu, 23. veebr. 2007, lk. 5-6

Control of charge transfer by conformational and electronic effects: Donor-donor and donor-acceptor phenyl pyrroles

International Nuclear Information System (INIS)

Neubauer, Antje; Bendig, Juergen; Rettig, Wolfgang

2009-01-01

Derivatives of N-pyrrolobenzene with a para-donor and a para-acceptor substituent on the benzene ring are compared. It is shown that by a suitable increase of the donor strength of the pyrrolo group, CT fluorescence can be achieved even for donor-donor-substituted benzenes. The ICT emission for sterically hindered compounds is more forbidden than that of unhindered phenyl pyrroles. This suggests conformational effects which induce a narrower twist angle distribution around a perpendicular minimum in the excited state.

Effect of anneal and quench on the nature of the dominant acceptors in ZnTe

International Nuclear Information System (INIS)

Bensahel, D.; Magnea, N.; Pautrat, J.L.; Pfister, J.C.; Revoil, L.

1978-01-01

Anneal and quench studies on high purity ZnTe have shown the dominant role of impurities and their solubilities as functions of stoichiometrical conditions. The role of 'b' acceptor, related to lithium, 'g' acceptor, related to silver, and 'a' acceptor of unknown nature is reported

Using Apple (Malus domestica, Pumpkin (Cucurbita maxima and Cinnamon (Cinnamom vertum to Obtain an Innovative Jam-Like Food Product

Directory of Open Access Journals (Sweden)

Maria Lidia IANCU

2017-11-01

Full Text Available The apple, the pumpkin and the cinnamon are raw materials that could be innovatively combined to produce a new sugar-preserved product following an original recipe. It can be considered in accordance with the European quality of jam-type varieties. It is a hybrid product, a component of “the European gastronomy” with old Bavarian roots and Romanian raw material. An adapted technological scheme and a recipe based on the TSS of the raw material and of the finished product were used. The quality indicators were determined using analytical methods. The PCA with the results provided by the panelists were used for the study of the aromatic profile. An identification of flavors, such as apple and cinnamon, is reported, which contributes to the specificity of the sensory profile of the jam. The new product has: TSS = 63.6 oBrix, TA = 0.2%, VA = 0.105 %. These values fall within the range of values for other jam and experimental jam assortments. The proportion of solids is 34%, which is far too low compared to the 45% minimum accepted limit. Taking into account that there is no “surface lifting” flaw, it is recommended to accept the value for the new assortment.

Electroluminescence from charge transfer states in Donor/Acceptor solar cells

DEFF Research Database (Denmark)

Sherafatipour, Golenaz; Madsen, Morten

Charge photocurrent generation is a key process in solar energy conversion systems. Effective dissociation of the photo-generated electron-hole pairs (excitons) has a strong influence on the efficiency of the organic solar cells. Charge dissociation takes place at the donor/acceptor interface via...... which the maximum open-circuit voltage can be estimated, and further can be used in the modeling and optimization of the OPV devices. [1] C. Deibe, T. Strobe, and V. Dyakonov, “Role of the charge transfer state in organic donor-acceptor solar cells,” Adv. Mater., vol. 22, pp. 4097–4111, 2010. [2] K...... charge transfer (CT) excitons, which is Coulombically bound interfacial electron- hole pairs residing at the donor/acceptor heterojunctions. The CT state represents an intermediate state between the exciton dissociation and recombination back to the ground state. Since the recombination of photo...

Dominant intrinsic acceptors in GaN and ZnO

Energy Technology Data Exchange (ETDEWEB)

Saarinen, K; Hautakangas, S; Tuomisto, F [Laboratory of Physics, Helsinki University of Technology, PO Box 1100, FI-02015 TKK (Finland)

2006-09-01

Positron annihilation measurements reveal negatively charged Ga vacancies in n-type GaN and Zn vacancies in n-type ZnO. Positron trapping at other negative defects is not observed, indicating that cation vacancies are the dominant acceptors in these materials. The vacancy concentrations are the same as the total acceptor densities determined in Hall experiments, confirming the dominant role of the vacancy defects. The Ga vacancy in GaN is found as the main compensating centre over the range of four orders of magnitude of intentional oxygen doping.

Dominant intrinsic acceptors in GaN and ZnO

International Nuclear Information System (INIS)

Saarinen, K; Hautakangas, S; Tuomisto, F

2006-01-01

Positron annihilation measurements reveal negatively charged Ga vacancies in n-type GaN and Zn vacancies in n-type ZnO. Positron trapping at other negative defects is not observed, indicating that cation vacancies are the dominant acceptors in these materials. The vacancy concentrations are the same as the total acceptor densities determined in Hall experiments, confirming the dominant role of the vacancy defects. The Ga vacancy in GaN is found as the main compensating centre over the range of four orders of magnitude of intentional oxygen doping

Charge Carrier Dynamics at Silver Nanocluster-Molecular Acceptor Interfaces

KAUST Repository

Almansaf, Abdulkhaleq

2017-07-01

A fundamental understanding of interfacial charge transfer at donor-acceptor interfaces is very crucial as it is considered among the most important dynamical processes for optimizing performance in many light harvesting systems, including photovoltaics and photo-catalysis. In general, the photo-generated singlet excitons in photoactive materials exhibit very short lifetimes because of their dipole-allowed spin radiative decay and short diffusion lengths. In contrast, the radiative decay of triplet excitons is dipole forbidden; therefore, their lifetimes are considerably longer. The discussion in this thesis primarily focuses on the relevant parameters that are involved in charge separation (CS), charge transfer (CT), intersystem crossing (ISC) rate, triplet state lifetime, and carrier recombination (CR) at silver nanocluster (NCs) molecular-acceptors interfaces. A combination of steady-state and femto- and nanosecond broadband transient absorption spectroscopies were used to investigate the charge carrier dynamics in various donor-acceptor systems. Additionally, this thesis was prolonged to investigate some important factors that influence the charge carrier dynamics in Ag29 silver NCs donor-acceptor systems, such as the metal doping and chemical structure of the nanocluster and molecular acceptors. Interestingly, clear correlations between the steady-state measurements and timeresolved spectroscopy results are found. In the first study, we have investigated the interfacial charge transfer dynamics in positively charged meso units of 5, 10, 15, 20-tetra (1- methyl-4-pyridino)-porphyrin tetra (p-toluene sulfonate) (TMPyP) and neutral charged 5, 10, 15, 20-tetra (4-pyridyl)-porphyrin (TPyP), with negatively charged undoped and gold (Au)- doped silver Ag29 NCs. Moreover, this study showed the impact of Au doping on the charge carrier dynamics of the system. In the second study, we have investigated the interfacial charge transfer dynamics in [Pt2 Ag23 Cl7 (PPh3

Ultrafast Photoinduced Electron Transfer in Bimolecular Donor-Acceptor Systems

KAUST Repository

Alsulami, Qana A.

2016-11-30

The efficiency of photoconversion systems, such as organic photovoltaic (OPV) cells, is largely controlled by a series of fundamental photophysical processes occurring at the interface before carrier collection. A profound understanding of ultrafast interfacial charge transfer (CT), charge separation (CS), and charge recombination (CR) is the key determinant to improving the overall performances of photovoltaic devices. The discussion in this dissertation primarily focuses on the relevant parameters that are involved in photon absorption, exciton separation, carrier transport, carrier recombination and carrier collection in organic photovoltaic devices. A combination of steady-state and femtosecond broadband transient spectroscopies was used to investigate the photoinduced charge carrier dynamics in various donor-acceptor systems. Furthermore, this study was extended to investigate some important factors that influence charge transfer in donor-acceptor systems, such as the morphology, energy band alignment, electronic properties and chemical structure. Interestingly, clear correlations among the steady-state measurements, time-resolved spectroscopy results, grain alignment of the electron transporting layer (ETL), carrier mobility, and device performance are found. In this thesis, we explored the significant impacts of ultrafast charge separation and charge recombination at donor/acceptor (D/A) interfaces on the performance of a conjugated polymer PTB7-Th device with three fullerene acceptors: PC71BM, PC61BM and IC60BA. Time-resolved laser spectroscopy and high-resolution electron microscopy can illustrate the basis for fabricating solar cell devices with improved performances. In addition, we studied the effects of the incorporation of heavy metals into π-conjugated chromophores on electron transfer by monitoring the triplet state lifetime of the oligomer using transient absorption spectroscopy, as understanding the mechanisms controlling intersystem crossing and

Spectroscopic studies of charge transfer complexes of some amino aromatic donors with some acceptors

International Nuclear Information System (INIS)

Al-Ani, S.S.

1989-01-01

Charge transfer (C.T.) complexes are the products of the weak reversible interactions between electron donors and electron acceptors. Sixteen novel C.T. complexes were studied and discussed. These complexes were formed from aromatic electron donors with various electron acceptors in absolute ethyl alcohol at 20 0 C. Electronic absorption spectra of these complexes and their donors and acceptors were taken. New charge transfer absorption bands appeared for these complexes in the UV-VIS region. The donors used are tetramethyl diamino benzophenone, P-amino-N:N-dimethyl aniline, tetramethyl-diamino-diphenylmethane, P-amino-azobenzene and benzidine, while the acceptors are iodine, bromine, picric acid, 2,4-dinitrophenol, trifluoroacetic acid and trichloroacetic acid. The results showed a disappearance of some donors and acceptors absorption bands. The energy of C.T. bands were calculated from which the ionization potentials of donors were obtained. The results showed that energies of C.T. Bands for complexes of a given donor with a series of acceptors are very similar. Some C.T. complexes showed low value of energy and high values of electrical conductivity. These are ionic complexes rather than molecular ones. 4 tabs.; 2 figs.; 99 refs

X-ray diffraction analysis of a human tRNAGly acceptor-stem microhelix isoacceptor at 1.18 Å resolution

International Nuclear Information System (INIS)

Eichert, André; Perbandt, Markus; Schreiber, Angela; Fürste, Jens P.; Betzel, Christian; Erdmann, Volker A.; Förster, Charlotte

2008-01-01

The tRNA Gly acceptor-stem microhelix isoacceptor from human cytoplasm was crystallized and X-ray diffraction analysis revealed diffraction to 1.18 Å resolution. The sequence of the microhelix was derived from the gene sequence with tRNA Database ID DG9990. Interest has been focused on comparative X-ray structure analyses of different tRNA Gly acceptor-stem helices. tRNA Gly /glycyl-tRNA synthetase belongs to the so-called class II system, in which the tRNA identity elements consist of simple and unique determinants that are located in the tRNA acceptor stem and the discriminator base. Comparative structure investigations of tRNA Gly microhelices provide insight into the role of tRNA identity elements. Predominant differences in the structures of glycyl-tRNA synthetases and in the tRNA identity elements between prokaryotes and eukaryotes point to divergence during the evolutionary process. Here, the crystallization and high-resolution X-ray diffraction analysis of a human tRNA Gly acceptor-stem microhelix with sequence 5′-G 1 C 2 A 3 U 4 U 5 G 6 G 7 -3′, 5′-C 66 C 67 A 68 A 69 U 70 G 71 C 72 -3′ is reported. The crystals belonged to the monoclinic space group C2, with unit-cell parameters a = 37.32, b = 37.61, c = 30.47 Å, β = 112.60° and one molecule per asymmetric unit. A data set was collected using synchrotron radiation and data were processed within the resolution range 50.0–1.18 Å. The structure was solved by molecular replacement

Berliinis võidutses Michael Haneke / Jüri Laulik

Index Scriptorium Estoniae

Laulik, Jüri, 1959-

2005-01-01

IX PÖFFil linastuv Michael Haneke film "Varjatud" ("Cache") võitis laupäeval mitu Euroopa Filmiakadeemia auhinda, sealhulgas parima filmi, parima lavastaja ja parima meesnäitleja (Daniel Auteuil) auhinna. Parima naisnäitleja tiitli pälvis Julia Jentsch ("Sophie Scholli viimased päevad"). Elutööpreemia sai sir Sean Connery

Michael Oakeshott´s Work as a Liberal-Conserv ative Paradigm

Directory of Open Access Journals (Sweden)

Josep Baqués

2014-01-01

Full Text Available As is the case with other thinkers linked to what can be broadly defined as conservatism, it is arguable whether Michael Oakeshott was just a conservative, or whether he was also a liberal. He often rejected this last label. He also tried to avoid the classic debate between the left/right wing divide, conferring instead a mantle of neutrality on his work. This analysis shows, on the one hand, that Oakeshott´s work is ideologically orientated and, on the other hand, that it contains a substantial liberal component. In fact, he offered a liberal-conservative synthesis in which the free market appears to be not only the best, but the only feasible outcome in the proposed scenario of political prudence. I will fi rst connect Oakeshott with the main traditions of thought, then analyse the theoretical implications of his position, and finally explore the consequences derived from all this for everyday political practice.

Michael Jackson antes del caos

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Juan Luciano Nieves

2015-01-01

Full Text Available Michael Jackson es un buen ejemplo de cómo utilizar las relaciones públicas para realizar o manipular la imagen de un producto a través de los medios de comunicación. Este ensayo pretende analizar los eventos que tuvieron lugar antes de que el cantante fuera acusado de abuso sexual contra un menor. Dichos eventos formaron parte de un plan muy bien delineado para disminuir los efectos de la inminente crisis que se acercaba. Este trabajo combina la crítica retórica de temas de fantasía con teoría de comunicación.

Polymer solar cells with novel fullerene-based acceptor

International Nuclear Information System (INIS)

Riedel, I.; Martin, N.; Giacalone, F.; Segura, J.L.; Chirvase, D.; Parisi, J.; Dyakonov, V.

2004-01-01

Alternative acceptor materials are possible candidates to improve the optical absorption and/or the open circuit voltage of polymer-fullerene solar cells. We studied a novel fullerene-type acceptor, DPM-12, for application in polymer-fullerene bulk heterojunction photovoltaic devices. Though DPM-12 has the identical redox potentials as methanofullerene PCBM, surprisingly high open circuit voltages in the range V OC =0.95 V were measured for OC 1 C 10 -PPV:DPM-12-based samples. The potential for photovoltaic application was studied by means of photovoltaic characterization of solar cells including current-voltage measurements and external quantum yield spectroscopy. Further studies were carried out by profiling the solar cell parameters vs. temperature and white light intensity

A perspectiva de Michael Apple para os estudos das políticas educacionais

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Luís Armando Gandin

Full Text Available Resumo Este artigo tem como objetivo analisar as contribuições de Michael Apple para o campo da pesquisa em políticas educacionais. Na extensa obra de Michael Apple, destacamos seis elementos que podem auxiliar aqueles que estão interessados na área de políticas em educação: o princípio epistemológico da análise relacional; o exame do Estado como relação; a herança de Antonio Gramsci e de Raymond Williams que Michael Apple incorpora no uso de conceitos como hegemonia e senso comum; a análise que Michael Apple faz das políticas educacionais como políticas culturais, como disputas por visão de mundo, como luta por consolidação de uma hegemonia que vai além do econômico; a sua postura de pesquisador; e a capacidade que Michael Apple tem de ir além da lógica da reprodução e determinação para enfatizar o papel da agência e da contra-hegemonia. Através de exemplos práticos da própria obra de Apple e de outras pesquisas empíricas, apresentam-se as implicações de cada um dos seis pontos acima citados para os pesquisadores interessados na área de políticas educacionais. Conclui-se que muitas das contribuições de Apple podem auxiliar em pesquisas nessa área, tendo em vista a discussão que o autor realiza em sua obra e sua crítica ao determinismo econômico nas análises do campo educacional, salientando a importância, assim, de aspectos que estão relacionados à esfera da cultura.

Fluorescent and Colorimetric Molecular Recognition Probe for Hydrogen Bond Acceptors

OpenAIRE

Pike, Sarah Jane; Hunter, Christopher Alexander

2018-01-01

The association constants for formation of 1 : 1 complexes between a H-bond donor, 1-naphthol, and a diverse range of charged and neutral H-bond acceptors have been measured using UV/vis absorption and fluorescence emission titrations. The performance of 1-naphthol as a dual colorimetric and fluorescent molecular recognition probe for determining the H-bond acceptor (HBA) parameters of charged and neutral solutes has been investigated in three solvents. The data were employed to establish sel...

Fullerene derivatives as components for 'plastic' photovoltaic cells

NARCIS (Netherlands)

Hummelen, J.C.; Knol, J.; Kadish, KM; Ruoff, RS

1998-01-01

Derivatives of [60]fullerene, mixed with conducting polymers to yield donor-acceptor bulk-heterojunction (beta-junction) materials, are useful in 'plastic' photovoltaic devices. In order to enhance the charge carrier mobilities in the two individual interpenetrating networks, one important goal of

DNA-based catalytic enantioselective intermolecular oxa-Michael addition reactions

NARCIS (Netherlands)

Megens, Rik P.; Roelfes, Gerard

2012-01-01

Using the DNA-based catalysis concept, a novel Cu(II) catalyzed enantioselective oxa-Michael addition of alcohols to enones is reported. Enantioselectivities of up to 86% were obtained. The presence of water is important for the reactivity, possibly by reverting unwanted side reactions such as

Characterization of derivates of carbo-anhydride by NMR; Caracterizacao de derivados do anidrido carbico por RMN

Energy Technology Data Exchange (ETDEWEB)

Campos, Marcos Pery Amaral [Instituto Militar de Engenharia (IME), Rio de Janeiro, RJ (Brazil); Bergter, Lothar [Cia. Souza Cruz, Rio de Janeiro, RJ (Brazil); Seidl, Peter Rudolf [Centro de Tecnologia Mineral, Rio de Janeiro, RJ (Brazil)

1994-12-31

The term molecular recognition may be applied to several phenomena of different complexities. The compounds which work as blockers or acceptors in this process are generally complexes with functional groups positioned in specific positions. This work presents the NMR characterization of carbo-anhydride derivates which are important in the preparation of synthetic acceptors 2 figs.

Reactivity of vinyl ethers and vinyl ribosides in UV-initiated free radical copolymerization with acceptor monomers.

Science.gov (United States)

Pichavant, Loic; Guillermain, Céline; Coqueret, Xavier

2010-09-13

The reactivity of various vinyl ethers and vinyloxy derivatives of ribose in the presence of diethyl fumarate or diethyl maleate was investigated for evaluating the potential of donor-acceptor-type copolymerization applied to unsaturated monomers derived from renewable feedstock. The photochemically induced polymerization of model monomer blends in the bulk state was monitored by infrared spectroscopy. The method allowed us to examine the influence of monomer pair structure on the kinetic profiles. The simultaneous consumption of both monomers was observed, supporting an alternating copolymerization mechanism. A lower reactivity of the blends containing maleates compared with fumarates was confirmed. The obtained kinetic data revealed a general correlation between the initial polymerization rate and the Hansen parameter δ(H) associated with the H-bonding aptitude of the donor monomer.

Electron Donor Acceptor Interactions. Final Progress Report

Energy Technology Data Exchange (ETDEWEB)

Moore, Ana L. [Arizona State Univ., Tempe, AZ (United States)

2002-08-16

The Gordon Research Conference (GRC) on Electron Donor Acceptor Interactions was held at Salve Regina University, Newport, Rhode Island, 8/11-16/02. Emphasis was placed on current unpublished research and discussion of the future target areas in this field.

Michael Kohlhaas or the Germans and Their Law

Directory of Open Access Journals (Sweden)

Heike Jung

2014-12-01

Full Text Available Asked to pick a single representative ‘German’ piece for a discourse on ‘Law and Literature’ one almost inevitably ends up with Kleist’s tale Michael Kohlhaas. It seems to be the literary incarnation of the German stance vis-à-vis the law. It is all about horses; it could just as well be about dogs. Kohlhaas fights a devastating battle, using legal means and outright violence, even warfare, for their recovery in good shape. Victorious eventually with his legal actions, he is happy to trade in his own life for this victory, thus giving an extreme example for the nice line between being in the right and pursuing this position with disproportionate rigour. Of course, the interpretations of Michael Kohlhaas (which, in its complete version, dates of 1810 have varied from epoch to epoch as well as from reader to reader. It is not possible to rehearse the bulk of ‘Kohlhaas literature’. In comparing legal cultures, it might be of interest to look into the question why such a somber story on the law forms part and will continue to form part of the German cultural heritage. Si se tiene que elegir un único representante “alemán” para una ponencia sobre “derecho y literatura”, es inevitable optar por la obra de Kleist, Michael Kohlhaas. Parece la encarnación literaria de la posición alemana hacia el derecho. El libro trata de caballos; también podría tratar sobre perros. Kohlhaas libra una batalla devastadora usando medios legales y la violencia pura y dura, incluso la guerra, para que se recuperen en buena forma. Finalmente resulta ganador mediante acciones legales, está contento de dedicar su propia vida para conseguir esta victoria, dando así un ejemplo extremo de la línea que existe entre tener la razón y seguir esta posición con un rigor desproporcionado. Por supuesto, las interpretaciones de Michael Kohlhaas (publicado en 1810 han variado de una época a otra, y de un lector a otro. No es posible revisar el grueso de

Effect of deviation from stoichiometry on the nature of shallow acceptor states in CdTe crystals

International Nuclear Information System (INIS)

Agrinskaya, N.V.; Shashkova, V.V.

1988-01-01

Photoconductivity and photoluminescence spectra in the region of donor-acceptor recombination of pure CdTe crystals, grown under conditions of different deviations from stoichiometry are investigated. It is shown that the predominant type of minor acceptors in n-type crystals (with Cd excess) differs from acceptors in p-type crystals (with Te excess). Residual acceptors replacing Te(P, As) prevail in n-type crystals and acceptors replacing Cd(Li, Na) prevail in p-type crystals. As a result of p-type crystal annealing a change of the type of prevailing aceptors accurs in Cd pairs (bands linked with P, As prevail) which testifies to the residual impurity reconstruction in Cd and Te sublattices

77 FR 69550 - Proposed Information Collection (Patient Satisfaction Survey Michael E. DeBakey Home Care Program...

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2012-11-19

... (Patient Satisfaction Survey Michael E. DeBakey Home Care Program) Activity: Comment Request AGENCY.... DeBakey Home Care Program. DATES: Written comments and recommendations on the proposed collection of...: Patient Satisfaction Survey Michael E. DeBakey Home Care Program, VA Form 10-0476. OMB Control Number...

76 FR 624 - Proposed Information Collection (Patient Satisfaction Survey Michael E. DeBakey Home Care Program...

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2011-01-05

... Collection (Patient Satisfaction Survey Michael E. DeBakey Home Care Program) Activity: Comment Request... satisfaction with the quality of services/care provided by home care program staff. An agency may not conduct... Form 10-0476).'' SUPPLEMENTARY INFORMATION: Title: Patient Satisfaction Survey Michael E. DeBakey Home...

The conceptualization of love in religious thought of George Florovsky and Michael Pomazansky

Directory of Open Access Journals (Sweden)

Pavenkov Oleg Vladimirovich

2015-04-01

Full Text Available The present article is concerned with the question of conceptualization of love in works of Fr. George Florovsky and Fr. Michael Pomazansky, Russian religious thinkers and theologists. We are studying the meaning and appropriacy of two words, ‘love’ (English and ‘любовь’ (Russian, that are the best to represent the agapelogical positive evaluation in Russian religious thought. Data for study was taken from ten different articles and extracts from books written by Fr. George Florovsky and Fr. Michael Pomazansky. On the basis of this analysis we develop semantic explications of words ‘love’ and ‘любовь’ as Christian spiritual concepts within the framework of theoretical approach of Natural Semantic Metalanguage (NSM. In summary we state that this article discusses, describes and determines some similarities and differences in understanding of concept ‘love’ in the affore-referenced works by Fr. George Florovsky and Fr. Michael Pomazansky.

Arenethiolatecopper(I) complexes as homogeneous catalysts for Michael addition reactions

NARCIS (Netherlands)

Koten, G. van; Klaveren, M. van; Lambert, F.; Eijkelkamp, D.J.F.M.; Grove, D.M.

1994-01-01

Arenethiolatocopper(I) complexes are shown to be efficient homogeneous catalysts in Michael addition reactions of several Grignard reagents to acyclic enones; the addition products are formed with excellent chemoselectivity (>99%) and good enantioselectivity (76% e.e.).

Michael Bloomberg ähvardab USA valimised "ära rikkuda" / Heiki Suurkask

Index Scriptorium Estoniae

Suurkask, Heiki, 1972-

2008-01-01

New Yorgi praegune linnapea Michael Bloomberg võib kolmanda kandidaadina sekkuda presidendikandidaatide valimiskampaaniasse, probleem on aga tema vähene tuntus. Lisa: Seni on riigipeakoha jaganud kaks suurparteid

Ex-situ activation of magnesium acceptors in InGaN/LED-structures

Energy Technology Data Exchange (ETDEWEB)

Kusch, Gunnar; Frentrup, Martin; Stellmach, Joachim; Kolbe, Tim; Wernicke, Tim; Pristovsek, Markus; Kneissl, Michael [Technische Universitaet Berlin, Institut fuer Festkoerperphysik, Hardenbergstr. 36, 10623 Berlin (Germany)

2011-07-01

One of the main problems limiting the output power of group-III-nitride compound light emitting diodes (LEDs) and laser diodes (LD) is the p-doping of nitrides with magnesium (Mg). During metal-organic vapor phase epitaxy (MOVPE) growth of (Al)GaN:Mg magnesium acceptors are passivated by hydrogen (H). By thermal annealing under nitrogen atmosphere the Mg-H bond can be cracked, thus activating the Mg acceptor. We have investigated ex-situ Mg-activation of the p-GaN layer and p-AlGaN electron blocking layer (EBL) in LEDs grown by MOVPE. Especially the activation of the AlGaN EBL is crucial. Simulations show, that a high doping level is required for effective electron blocking and a high injection efficiency. Additionally the acceptor activation energy is expected to increase with increasing Al-content, reducing the free hole concentration in the EBL. Electroluminescence spectroscopy (EL) was performed to determine the influence of the activation on the external quantum efficiency of the LED structure. Furthermore we used CV measurements to determine the Mg-acceptor concentration.

Professor Porter ja tema viis konkurentsitegurit / Michael E Porter

Index Scriptorium Estoniae

Porter, Michael E

2008-01-01

Maailmas tuntud juhtimisguru Michael Porter viie konkurentsijõu teooriast ja selle rakendatavusest erinevates valdkondades. Lisad: Erinevused valdkondade kasumlikkuses; 5 määravat konkurentsijõudu; Investeeritud kapitali keskmine tasuvus; Mõnede USA tegevusvaldkondade kasumlikkus; Valdkonnaanalüüs praktikas; Valdkonna määratlemine; Valdkonnaanalüüsi sammud

Michael Polanyi on the Education and Knowledge of Scientists.

Science.gov (United States)

Jacobs, Struan

2000-01-01

Explains why teachers addressing the nature of science should know the work of Michael Polanyi. Outlines Polanyi's intellectual career and examines his ideas on the education of scientists, research, and knowledge. Polanyi presaged Kuhn, Feyerabend, and the constructivists, yet insisted that science produces true knowledge about reality. (Contains…

Chinese Middle Classes: Taiwan, Hong Kong, Macao and China. Edited by Hsin-Huang Michael Hsiao

DEFF Research Database (Denmark)

Brødsgaard, Kjeld Erik

2018-01-01

Book review of: Chinese Middle Classes:Taiwan, Hong Kong, Macao and China. Edited by Hsin-Huang Michael Hsiao. Abingdon: Routledge, 2014. Pp. 268. ISBN 10: 1138120847; ISBN 13: 978-1138120846......Book review of: Chinese Middle Classes:Taiwan, Hong Kong, Macao and China. Edited by Hsin-Huang Michael Hsiao. Abingdon: Routledge, 2014. Pp. 268. ISBN 10: 1138120847; ISBN 13: 978-1138120846...

Uniaxially oriented polycrystalline thin films and air-stable n-type transistors based on donor-acceptor semiconductor (diC8BTBT)(FnTCNQ) [n = 0, 2, 4

Science.gov (United States)

Shibata, Yosei; Tsutsumi, Jun'ya; Matsuoka, Satoshi; Matsubara, Koji; Yoshida, Yuji; Chikamatsu, Masayuki; Hasegawa, Tatsuo

2015-04-01

We report the fabrication of high quality thin films for semiconducting organic donor-acceptor charge-transfer (CT) compounds, (diC8BTBT)(FnTCNQ) (diC8BTBT = 2,7-dioctyl[1]benzothieno[3,2-b][1]benzothiophene and FnTCNQ [n = 0,2,4] = fluorinated derivatives of 7,7,8,8,-tetracyanoquinodimethane), which have a high degree of layered crystallinity. Single-phase and uniaxially oriented polycrystalline thin films of the compounds were obtained by co-evaporation of the component donor and acceptor molecules. Organic thin-film transistors (OTFTs) fabricated with the compound films exhibited n-type field-effect characteristics, showing a mobility of 6.9 × 10-2 cm2/V s, an on/off ratio of 106, a sub-threshold swing of 0.8 V/dec, and an excellent stability in air. We discuss the suitability of strong intermolecular donor-acceptor interaction and the narrow CT gap nature in compounds for stable n-type OTFT operation.

Sterilisation: characteristics of vasectomy acceptors in Delhi.

Science.gov (United States)

Sarkar, N N

1993-01-01

The place of vasectomy within the sterilisation programme in Delhi over the period 1983-88 is reviewed and data on vasectomy acceptance and characteristics of acceptors are analysed. Findings suggest a need to improve the strategy for the promotion of vasectomy within the metropolis.

Pengaruh Tipografi pada Era Massimo Vignelli terhadap Tipografi Michael Bierut

Directory of Open Access Journals (Sweden)

Irwan Harnoko

2011-10-01

Full Text Available Massimo Vignelli is a senior graphic designer lived in New York, as a vocal modernism against post-modernism. His statement firmly opposing post-modernism in several occasions: interview in Helvetica the movie, typeradio, talkshow, and some articles in Looking Closer or AIGA Journal. Graphic design works of Massimo Vignelli reflected his characteristic, which is firmly choosing typeface. Typefaces of Vignelly are around 5 typefaces: Bodoni, Helvetica, Times Roman, Century, and Futura. The article uses formal analysis method. The writers collected materials about Michael Bierut, Massimo VIgnelli and Tibor Kalman from books and websites. The writers compare the typeface opinion of Massimo Vignelli (modernism designer, Michael Bierut designer (transition era designer from modernism to post-modernism, and Tibor Kalman (a designer in A Century of Graphic Design, as the influencer of Bierut’s betrayal over Vignelli. 

Tweeting Prayers and Communicating Grief over Michael Jackson Online

Science.gov (United States)

Sanderson, Jimmy; Cheong, Pauline Hope

2010-01-01

Death and bereavement are human experiences that new media helps facilitate alongside creating new social grief practices that occur online. This study investigated how people's postings and tweets facilitated the communication of grief after pop music icon Michael Jackson died. Drawing on past grief research, religion, and new media studies, a…

78 FR 6851 - Proposed Information Collection (Patient Satisfaction Survey Michael E. DeBakey Home Care Program...

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2013-01-31

... (Patient Satisfaction Survey Michael E. DeBakey Home Care Program) Activity: Comment Request AGENCY... Satisfaction Survey Michael E. DeBakey Home Care Program, VA Form 10-0476. OMB Control Number: 2900-0775. Type... home care program staff. An agency may not conduct or sponsor, and a person is not required to respond...

Atomic scale images of acceptors in III-V semiconductors. Band bending, tunneling paths and wave functions

Energy Technology Data Exchange (ETDEWEB)

Loth, S.

2007-10-26

This thesis reports measurements of single dopant atoms in III-V semiconductors with low temperature Scanning Tunneling Microscopy (STM) and Scanning Tunneling Spectroscopy (STS). It investigates the anisotropic spatial distribution of acceptor induced tunneling processes at the {l_brace}110{r_brace} cleavage planes. Two different tunneling processes are identified: conventional imaging of the squared acceptor wave function and resonant tunneling at the charged acceptor. A thorough analysis of the tip induced space charge layers identifies characteristic bias windows for each tunnel process. The symmetry of the host crystal's band structure determines the spatial distribution of the tunneling paths for both processes. Symmetry reducing effects at the surface are responsible for a pronounced asymmetry of the acceptor contrasts along the principal [001] axis. Uniaxial strain fields due to surface relaxation and spin orbit interaction of the tip induced electric field are discussed on the basis of band structure calculations. High-resolution STS studies of acceptor atoms in an operating p-i-n diode confirm that an electric field indeed changes the acceptor contrasts. In conclusion, the anisotropic contrasts of acceptors are created by the host crystal's band structure and concomitant symmetry reduction effects at the surface. (orig.)

Triplet Tellurophene-Based Acceptors for Organic Solar Cells.

Science.gov (United States)

Yang, Lei; Gu, Wenxing; Lv, Lei; Chen, Yusheng; Yang, Yufei; Ye, Pan; Wu, Jianfei; Hong, Ling; Peng, Aidong; Huang, Hui

2018-01-22

Triplet materials have been employed to achieve high-performing organic solar cells (OSCs) by extending the exciton lifetime and diffusion distances, while the triplet non-fullerene acceptor materials have never been reported for bulk heterojunction OSCs. Herein, for the first time, three triplet molecular acceptors based on tellurophene with different degrees of ring fusing were designed and synthesized for OSCs. Significantly, these molecules have long exciton lifetime and diffusion lengths, leading to efficient power conversion efficiency (7.52 %), which is the highest value for tellurophene-based OSCs. The influence of the extent of ring fusing on molecular geometry and OSCs performance was investigated to show the power conversion efficiencies (PCEs) continuously increased along with increasing the extent of ring fusing. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Organic Donor-Acceptor Complexes as Novel Organic Semiconductors.

Science.gov (United States)

Zhang, Jing; Xu, Wei; Sheng, Peng; Zhao, Guangyao; Zhu, Daoben

2017-07-18

Organic donor-acceptor (DA) complexes have attracted wide attention in recent decades, resulting in the rapid development of organic binary system electronics. The design and synthesis of organic DA complexes with a variety of component structures have mainly focused on metallicity (or even superconductivity), emission, or ferroelectricity studies. Further efforts have been made in high-performance electronic investigations. The chemical versatility of organic semiconductors provides DA complexes with a great number of possibilities for semiconducting applications. Organic DA complexes extend the semiconductor family and promote charge separation and transport in organic field-effect transistors (OFETs) and organic photovoltaics (OPVs). In OFETs, the organic complex serves as an active layer across extraordinary charge pathways, ensuring the efficient transport of induced charges. Although an increasing number of organic semiconductors have been reported to exhibit good p- or n-type properties (mobilities higher than 1 or even 10 cm 2 V -1 s -1 ), critical scientific challenges remain in utilizing the advantages of existing semiconductor materials for more and wider applications while maintaining less complicated synthetic or device fabrication processes. DA complex materials have revealed new insight: their unique molecular packing and structure-property relationships. The combination of donors and acceptors could offer practical advantages compared with their unimolecular materials. First, growing crystals of DA complexes with densely packed structures will reduce impurities and traps from the self-assembly process. Second, complexes based on the original structural components could form superior mixture stacking, which can facilitate charge transport depending on the driving force in the coassembly process. Third, the effective use of organic semiconductors can lead to tunable band structures, allowing the operation mode (p- or n-type) of the transistor to be

A Good Time: A Conversation with C. Michael Nelson

Science.gov (United States)

Zabel, Robert; Kaff, Marilyn; Teagarden, Jim

2015-01-01

C. Michael Nelson began his special education career as a teacher of adolescents with learning and behavior disorders. He has worked as a child psychologist and as a professor with the Department of Special Education and Rehabilitation Counseling at the University of Kentucky. He coordinated the graduate Personnel Preparation Program for Teachers…

Aza-Michael Reaction for an Undergraduate Organic Chemistry Laboratory

Science.gov (United States)

Nigam, Manisha; Rush, Brittney; Patel, Jay; Castillo, Raul; Dhar, Preeti

2016-01-01

A green, aza-Michael reaction is described that can be used to teach undergraduate students conjugate addition of nitrogen nucleophile to an a,ß-unsaturated ester. Students analyze spectral data of the product obtained from the assigned reaction to determine product structure and propose the mechanism of its formation. The experiment requires…

Vacancy clustering and acceptor activation in nitrogen-implanted ZnO

Science.gov (United States)

Børseth, Thomas Moe; Tuomisto, Filip; Christensen, Jens S.; Monakhov, Edouard V.; Svensson, Bengt G.; Kuznetsov, Andrej Yu.

2008-01-01

The role of vacancy clustering and acceptor activation on resistivity evolution in N ion-implanted n -type hydrothermally grown bulk ZnO has been investigated by positron annihilation spectroscopy, resistivity measurements, and chemical profiling. Room temperature 220keV N implantation using doses in the low 1015cm-2 range induces small and big vacancy clusters containing at least 2 and 3-4 Zn vacancies, respectively. The small clusters are present already in as-implanted samples and remain stable up to 1000°C with no significant effect on the resistivity evolution. In contrast, formation of the big clusters at 600°C is associated with a significant increase in the free electron concentration attributed to gettering of amphoteric Li impurities by these clusters. Further annealing at 800°C results in a dramatic decrease in the free electron concentration correlated with activation of 1016-1017cm-3 acceptors likely to be N and/or Li related. The samples remain n type, however, and further annealing at 1000°C results in passivation of the acceptor states while the big clusters dissociate.

Bond of donor-acceptor interaction in metal-ligand system with energies of Fermi electrons

International Nuclear Information System (INIS)

Vlasov, Yu.V.; Khentov, V.Ya.; Velikanova, L.N.; Semchenko, V.V.

1993-01-01

Role of quantum nature of metal (W, Mo and others) in donor-acceptor interaction of metal salicylalaniline - aprotic solvent was discussed. The dependence of dissolution rate and activation energy of donor-acceptor interaction on electron energy was established

[An exceptional human relationship (Michael P. Kierkegaard, Søren Kierkegaard)].

Science.gov (United States)

Jacobs, R

1978-01-01

There were a father and a son, Michael and Sören Kierkegaard, both highly talented, imaginitive, witty, humorous, especially interested in shrewd dialectrical dialogues respectively debates, both profound melancholy ponderers. But according to very own individuality their congeniality wasn't absolute. The father, being under a questionable rigorous opinion of sin, suffered from undeserved divine grace since early childhood. And Michael Kierkegaard made Sören anxious with the religious experience of original sin. This anxiety moved (touched or affected) the sensitive son mighty. Nevertheless he should not despair hopelessly like his unlucky father. On the contrary: Sørens incomparable melancholy, mental agony and anxiety (fear or anguish) forced the faith, existing independently of them, in a radical refining. That is why Sören Kierkegaard succeeded in sublimation of all psychological and philosophic (al) attitudes (or opinions) in the sphere of religiousness. And the result? A novel philosophy of life: Christian existentialism.

Shallow acceptors in strained Ge/Ge1-xSix heterostructures with quantum wells

International Nuclear Information System (INIS)

Aleshkin, V.Ya.; Andreev, B.A.; Gavrilenko, V.I.; Erofeeva, I.V.; Kozlov, D.V.; Kuznetsov, O.A.

2000-01-01

Dependence of acceptor localized state energies in quantum wells (strained layers of Ge in heterostructures Ge/Ge 1-x Si x ) on the width of quantum well and position in it was studied theoretically. Spectrum of impurity absorption in the far infrared range was calculated. Comparison of the results calculated and observed photoconductivity spectra permits estimating acceptor distribution over quantum well and suggesting conclusion that acceptors can be largely concentrated near heteroboundaries. Absorption spectrum was calculated bearing in mind resonance impurity states, which permits explaining the observed specific features in the photoconductivity spectrum short-wave range by transition to resonance energy levels, bound to upper subzones of dimensional quantization [ru

Thiophene-rich fused-aromatic thienopyrazine acceptor for donor–acceptor low band-gap polymers for OTFT and polymer solar cell applications

KAUST Repository

Mondal, Rajib

2010-01-01

Thiophene enriched fused-aromatic thieno[3,4-b]pyrazine systems were designed and employed to produce low band gap polymers (Eg = 1.0-1.4 eV) when copolymerized with fluorene and cyclopentadithiophene. The copolymers are mainly investigated for organic thin film transistor and organic photovoltaic applications. Molecular packing in the thin films of these polymers was investigated using Grazing incidence X-ray Scattering. Although both fluorene and cyclopentadithiophene polymers follow similar face to face π-π stacking, the latter polymers show much smaller lamellar d-spacings due to side-chain interdigitation between the lamellae. This lead to the higher charge carrier mobilities in cyclopentadithiophene polymers (up to 0.044 cm2/V.s) compared to fluorene polymers (up to 8.1 × 10-3 cm2/V.s). Power conversion efficiency of 1.4% was achieved using fluorene copolymer in solar cells with a fullerene derivative as an acceptor. Although the cyclopentadithiophene polymers show lower band gaps with higher absorption coefficients compared to fluorene copolymers, but the power conversion efficiencies in solar cells of these polymers are low due to their low ionization potentials. © The Royal Society of Chemistry 2010.

On the Molecular Origin of Charge Separation at the Donor-Acceptor Interface

KAUST Repository

Sini, Gjergji

2018-01-22

Fullerene-based acceptors have dominated organic solar cells for almost two decades. It is only within the last few years that alternative acceptors rival their dominance, introducing much more flexibility in the optoelectronic properties of these material blends. However, a fundamental physical understanding of the processes that drive charge separation at organic heterojunctions is still missing, but urgently needed to direct further material improvements. Here a combined experimental and theoretical approach is used to understand the intimate mechanisms by which molecular structure contributes to exciton dissociation, charge separation, and charge recombination at the donor–acceptor (D–A) interface. Model systems comprised of polythiophene-based donor and rylene diimide-based acceptor polymers are used and a detailed density functional theory (DFT) investigation is performed. The results point to the roles that geometric deformations and direct-contact intermolecular polarization play in establishing a driving force (energy gradient) for the optoelectronic processes taking place at the interface. A substantial impact for this driving force is found to stem from polymer deformations at the interface, a finding that can clearly lead to new design approaches in the development of the next generation of conjugated polymers and small molecules.

Fullerene Derivatives as Components for ‘Plastic’ Photovoltaic Cells

NARCIS (Netherlands)

Knol, Joop; Hummelen, Jan C.

1998-01-01

Derivatives of [60]fullerene, mixed with conducting polymers to yield donor-acceptor bulk-heterojunction (β-junction) materials, are useful in ‘plastic’ photovoltaic devices. In order to enhance the charge carrier mobilities in the two individual interpenetrating networks, one important goal of our

Physicochemical and Antioxidant Properties of Chitosan Films Incorporated with Cinnamon Oil

Directory of Open Access Journals (Sweden)

Marco A. López-Mata

2015-01-01

Full Text Available Chitosan films (CF with cinnamon bark oil (CO incorporated at 0% (control, 0.25%, 0.5%, and 1.0% v/v were prepared by an emulsion method. The films were characterized based on their physical properties (solubility, water vapor permeability, optical property, and microstructure and antioxidant properties (DPPH, ABTS, and its protective effects on human erythrocytes. The results showed that the incorporation of 0.5 and 1.0% of CO into the CF significantly decreased its solubility to 22% of the control (p<0.05. The water vapor permeability of the CF-CO was significantly reduced to 40% with low concentrations of CO (0.25% incorporated into the CF. In general, the films presented a yellow coloration and an increase in transparency with the incorporation of CO into the CF. It was also observed that the incorporation of CO increased the antioxidant activity between 6.0-fold and 14.5-fold compared to the control, and the protective capacity against erythrocyte hemolysis increased by as much as 80%.

Synthesis of OMS Materials and Investigation of Their Acceptor-Donor Characteristics.

Science.gov (United States)

Grajek, H; Paciura-Zadrożna, J; Choma, J; Michalski, E; Witkiewicz, Z

2012-10-01

Three ordered mesoporous siliceous (OMS) materials known as MCM41s-unmodified MCM-41C16 ("C16"), and two MCM41s with different surface functionalities: MCM-41C16-SH ("C16-SH") and MCM-41C16-NH 2 ("C16-NH 2 ")-were synthesized and studied by inverse gas chromatography in order to determine their acceptor-donor properties. The specific retention volumes of nonpolar and polar probes that were chromatographed on these ordered mesoporous silica adsorbents were evaluated under infinite dilution conditions. Two methods were employed to calculate the standard free energy of adsorption, Δ G ads , of each chromatographed probe on the basis its specific retention volume. These Δ G ads values were then employed to estimate the van der Waals contribution and the specific contribution of the free surface energy for each MCM41. DN values (donor numbers, based on the Gutmann scale) and AN* values (acceptor numbers, based on the Riddle-Fowkes scale) were employed to determine the values of parameters that characterize the ability of the MCM41s to act as electron acceptors (parameter: K A ) and donors (parameter: K D ). Considering the different compositions of the probes, each of which has different acceptor-donor properties, a new chromatographic test to supplement the Grob test is suggested.

Synergistic Effect of the Lactoperoxidase System and Cinnamon Essential Oil on Total Flora and Salmonella Growth Inhibition in Raw Milk

Directory of Open Access Journals (Sweden)

Chiraz Abbes

2018-01-01

Full Text Available Despite its antibacterial and antipathogenic effects, the heat treatment of milk induces undesirable changes that can be noted in the overall properties of ultrahigh temperature (UHT milk, such as changes in nutritional and organoleptic properties. Our goal is to find new nonthermal antibacterial technologies for the preservation of raw milk (RM. This study investigates the possible synergistic effect of using a combination of the lactoperoxidase system (LS and 3 μg mL−1 of cinnamon essential oil (cinnamon EO to inactivate the total flora of milk and Salmonella Hadar (S. Hadar. The LS was activated with 30 mg L−1 sodium percarbonate and 14 mg L−1 of sodium thiocyanate. Using this approach, we obtained a synergistic effect with a complete inhibition of the activity of the total flora of the milk and S. Hadar after 12 hours at 25°C. In addition, the attainment of synergy was defined when the inhibitory effect of the two compounds together was greater than the effect observed by each compound added alone. Moreover, the monitoring of the synergistic effect at 4°C for 5 days showed complete inhibition of total flora for 3 days and for S. Hadar it was up to 5 days. To summarize, the current study clearly identified a new inhibitory combination that may be used in food-based applications.

Positively charged phosphorus as a hydrogen bond acceptor

DEFF Research Database (Denmark)

Hansen, Anne Schou; Du, Lin; Kjærgaard, Henrik Grum

2014-01-01

Phosphorus (P) is an element that is essential to the life of all organisms, and the atmospheric detection of phosphine suggests the existence of a volatile biogeochemical P cycle. Here, we investigate the ability of P to participate in the formation of OH···P hydrogen bonds. Three bimolecular......-stretching frequency red shifts and quantum chemical calculations, we find that P is an acceptor atom similar in strength to O and S and that all three P, O, and S atoms are weaker acceptors than N. The quantum chemical calculations show that both H and P in the OH···P hydrogen bond have partial positive charges......, as expected from their electronegativities. However, the electrostatic potentials show a negative potential area on the electron density surface around P that facilitates formation of hydrogen bonds....

A Nonfullerene Small Molecule Acceptor with 3D Interlocking Geometry Enabling Efficient Organic Solar Cells.

Science.gov (United States)

Lee, Jaewon; Singh, Ranbir; Sin, Dong Hun; Kim, Heung Gyu; Song, Kyu Chan; Cho, Kilwon

2016-01-06

A new 3D nonfullerene small-molecule acceptor is reported. The 3D interlocking geometry of the small-molecule acceptor enables uniform molecular conformation and strong intermolecular connectivity, facilitating favorable nanoscale phase separation and electron charge transfer. By employing both a novel polymer donor and a nonfullerene small-molecule acceptor in the solution-processed organic solar cells, a high-power conversion efficiency of close to 6% is demonstrated. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

The Effect of Acceptor and Donor Doping on Oxygen Vacancy Concentrations in Lead Zirconate Titanate (PZT).

Science.gov (United States)

Slouka, Christoph; Kainz, Theresa; Navickas, Edvinas; Walch, Gregor; Hutter, Herbert; Reichmann, Klaus; Fleig, Jürgen

2016-11-22

The different properties of acceptor-doped (hard) and donor-doped (soft) lead zirconate titanate (PZT) ceramics are often attributed to different amounts of oxygen vacancies introduced by the dopant. Acceptor doping is believed to cause high oxygen vacancy concentrations, while donors are expected to strongly suppress their amount. In this study, La 3+ donor-doped, Fe 3+ acceptor-doped and La 3+ /Fe 3+ -co-doped PZT samples were investigated by oxygen tracer exchange and electrochemical impedance spectroscopy in order to analyse the effect of doping on oxygen vacancy concentrations. Relative changes in the tracer diffusion coefficients for different doping and quantitative relations between defect concentrations allowed estimates of oxygen vacancy concentrations. Donor doping does not completely suppress the formation of oxygen vacancies; rather, it concentrates them in the grain boundary region. Acceptor doping enhances the amount of oxygen vacancies but estimates suggest that bulk concentrations are still in the ppm range, even for 1% acceptor doping. Trapped holes might thus considerably contribute to the charge balancing of the acceptor dopants. This could also be of relevance in understanding the properties of hard and soft PZT.

The Effect of Acceptor and Donor Doping on Oxygen Vacancy Concentrations in Lead Zirconate Titanate (PZT

Directory of Open Access Journals (Sweden)

Christoph Slouka

2016-11-01

Full Text Available The different properties of acceptor-doped (hard and donor-doped (soft lead zirconate titanate (PZT ceramics are often attributed to different amounts of oxygen vacancies introduced by the dopant. Acceptor doping is believed to cause high oxygen vacancy concentrations, while donors are expected to strongly suppress their amount. In this study, La3+ donor-doped, Fe3+ acceptor-doped and La3+/Fe3+-co-doped PZT samples were investigated by oxygen tracer exchange and electrochemical impedance spectroscopy in order to analyse the effect of doping on oxygen vacancy concentrations. Relative changes in the tracer diffusion coefficients for different doping and quantitative relations between defect concentrations allowed estimates of oxygen vacancy concentrations. Donor doping does not completely suppress the formation of oxygen vacancies; rather, it concentrates them in the grain boundary region. Acceptor doping enhances the amount of oxygen vacancies but estimates suggest that bulk concentrations are still in the ppm range, even for 1% acceptor doping. Trapped holes might thus considerably contribute to the charge balancing of the acceptor dopants. This could also be of relevance in understanding the properties of hard and soft PZT.

Electrochemical synthesis of novel {pi}-extended phenoxazine derivatives of porphyrincatecholes

Energy Technology Data Exchange (ETDEWEB)

Osati, Samira; Davarani, Saied Saeed Hosseiny [Department of Chemistry, Faculty of Science, Shahid Beheshti University, G.C, Evin, 1983963113 Tehran (Iran, Islamic Republic of); Safari, Nasser, E-mail: n-safari@cc.sbu.ac.ir [Department of Chemistry, Faculty of Science, Shahid Beheshti University, G.C, Evin, 1983963113 Tehran (Iran, Islamic Republic of); Banitaba, Mohammad Hossein [Department of Chemistry, Faculty of Science, Shahid Beheshti University, G.C, Evin, 1983963113 Tehran (Iran, Islamic Republic of)

2011-10-30

Three new functionalized phenoxazine-catechol porphyrins 7a-c have been synthesized by a green one-pot method and structurally characterized by spectroscopic analysis. The electro-oxidation of 5,10,15,20-tetrakis(2,3-dihydroxyphenyl) porphyrins(1a-c) with four catechol units in the presence of 2-aminophenol 8 as bidentate nucleophile has been done and phenoxazine rings have been formed by intermolecular and intramolecular Michael addition reactions. Spectroscopic characterization and voltammetry results have allowed us to propose four independent ECEC mechanisms for the electrochemical oxidation pathway. The functionalization of the porphyrins affected their photophysical properties. Expansion of the UV-vis spectrum range and the decrease of the fluorescence intensity of the products would support the energy transfer between the porphyrin core excited states to the four substitutions as the electron acceptor subunits. SEM images indicate that this method produces regularly shaped manganese porphyrin nano-particles 7c that possess a cubic nano structure.

Electron paramagnetic resonance study of neutral Mg acceptors in β-Ga2O3 crystals

Science.gov (United States)

Kananen, B. E.; Halliburton, L. E.; Scherrer, E. M.; Stevens, K. T.; Foundos, G. K.; Chang, K. B.; Giles, N. C.

2017-08-01

Electron paramagnetic resonance (EPR) is used to directly observe and characterize neutral Mg acceptors ( M gGa0 ) in a β-Ga2O3 crystal. These acceptors, best considered as small polarons, are produced when the Mg-doped crystal is irradiated at or near 77 K with x rays. During the irradiation, neutral acceptors are formed when holes are trapped at singly ionized Mg acceptors ( M gGa- ). Unintentionally present Fe3+ (3d5) and Cr3+ (3d3) transition-metal ions serve as the corresponding electron traps. The hole is localized in a nonbonding p orbital on a threefold-coordinated oxygen ion adjacent to an Mg ion at a sixfold-coordinated Ga site. These M gGa0 acceptors (S = 1/2) have a slightly anisotropic g matrix (principal values are 2.0038, 2.0153, and 2.0371). There is also partially resolved 69Ga and 71Ga hyperfine structure resulting from unequal interactions with the two Ga ions adjacent to the hole. With the magnetic field along the a direction, hyperfine parameters are 2.61 and 1.18 mT for the 69Ga nuclei at the two inequivalent neighboring Ga sites. The M gGa0 acceptors thermally convert back to their nonparamagnetic M gGa- charge state when the temperature of the crystal is raised above approximately 250 K.

New Models at Lasell: Q&A with President Michael Alexander

Science.gov (United States)

Harney, John O.

2018-01-01

The "New England Journal of Higher Education" ("NEJHE") Executive Editor John O. Harney had the chance to catch up with Lasell College President Michael Alexander about the small Newton, Massachusetts, college's plans to challenge the higher education business model. The interview is presented in this article.

Locomotory and physiological responses induced by clove and cinnamon essential oils in the maize weevil Sitophilus zeamais.

Science.gov (United States)

Gonzales Correa, Yenis Del Carmen; Faroni, Lêda R A; Haddi, Khalid; Oliveira, Eugênio E; Pereira, Eliseu José G

2015-11-01

Plant essential oils have been suggested as a suitable alternative for controlling stored pests worldwide. However, very little is known about the physiological or behavioral responses induced by these compounds in insect populations that are resistant to traditional insecticides. Thus, this investigation evaluated the toxicity (including the impacts on population growth) as well as the locomotory and respiratory responses induced by clove, Syzygium aromaticum L., and cinnamon, Cinnamomum zeylanicum L., essential oils in Brazilian populations of the maize weevil Sitophilus zeamais. We used populations that are resistant to phosphine and pyrethroids (PyPhR), only resistant to pyrethroids (PyR1 and PyR2) or susceptible to both insecticide types (SUS). The PyPhR population was more tolerant to cinnamon essential oil, and its population growth rate was less affected by both oil types. Insects from this population reduced their respiratory rates (i.e., CO2 production) after being exposed to both oil types and avoided (in free choice-experiments) or reduced their mobility on essential oil-treated surfaces. The PyR1 and PyR2 populations reduced their respiratory rates, avoided (without changing their locomotory behavior in no-choice experiments) essential oil-treated surfaces and their population growth rates were severely affected by both oil types. Individuals from SUS population increased their mobility on surfaces that were treated with both oil types and showed the highest levels of susceptibility to these oils. Our findings indicate that S. zeamais populations that are resistant to traditional insecticides might have distinct but possibly overlapping mechanisms to mitigate the actions of essential oils and traditional insecticides. Copyright © 2015 Elsevier Inc. All rights reserved.

"Alarme de incêndio": Michael Löwy e a crítica ecossocialista da civilização capitalista moderna "Fire alarm": Michael Löwy and the ecosocialist critique of the modern capitalist civilization

Directory of Open Access Journals (Sweden)

Fabio Mascaro Querido

2013-04-01

Full Text Available A emergência da crise ecológica, como sintoma mais nítido de uma verdadeira crise civilizató-ria, impôs novos desafios ao pensamento crítico e, em especial, ao marxismo. Partindo desse pressuposto, o objetivo deste artigo é apresentar a defesa de Michael Löwy de uma radicalização ecossocialista da crítica marxista da modernidade, tarefa para a qual a grande recusa de Walter Benjamin das ideologias do pro- gresso é uma das fontes decisivas de inspiração. Para Michael Löwy, a ruptura com as ideologias do progresso e com o paradigma civilizatório capitalista moderno é uma condição indispensável para a atua-lização ecossocialista do marxismo.The emergence of the ecological crisis as a clearer symptom of a true civilizatory crisis has imposed new challenges to critical thought and, in particular, to Marxism. Based on this assumption, this article aims to present Michael Löwy's defense of an ecosocialist radicalization of the Marxist critique of modernity, a task for which Walter Benjamin's great refusal of the ideologies of progress is one of the critical sources of inspiration. To Michael Löwy, breaking away from the ideologies of progress and from the modern capitalistic civilizatory paradigm is a prerequisite for the ecosocialist updating of Marxism.

Interface effects on acceptor qubits in silicon and germanium

International Nuclear Information System (INIS)

Abadillo-Uriel, J C; Calderón, M J

2016-01-01

Dopant-based quantum computing implementations often require the dopants to be situated close to an interface to facilitate qubit manipulation with local gates. Interfaces not only modify the energies of the bound states but also affect their symmetry. Making use of the successful effective mass theory we study the energy spectra of acceptors in Si or Ge taking into account the quantum confinement, the dielectric mismatch and the central cell effects. The presence of an interface puts constraints to the allowed symmetries and leads to the splitting of the ground state in two Kramers doublets (Mol et al 2015 Appl. Phys. Lett. 106 203110). Inversion symmetry breaking also implies parity mixing which affects the allowed optical transitions. Consequences for acceptor qubits are discussed. (paper)

Cinnamomum zeylanicum (Ceylon cinnamon) as a potential pharmaceutical agent for type-2 diabetes mellitus: study protocol for a randomized controlled trial

OpenAIRE

Ranasinghe, Priyanga; Galappaththy, Priyadarshani; Constantine, Godwin Roger; Jayawardena, Ranil; Weeratunga, Hasitha Dhananjaya; Premakumara, Sirimal; Katulanda, Prasad

2017-01-01

Background Previous studies have explored the anti-diabetic effects of Cinnamomum cassia extract in vivo and in vitro. However, there are no studies at present exploring the effects of the indigenous species of Sri Lankan cinnamon (Cinnamomum zeylanicum) in patients with diabetes mellitus. The present study aims to evaluate the potential effects of Cinnamomum zeylanicum extract as a pharmaceutical agent in patients with type-2 diabetes mellitus. Methods/design The study will be conducted as a...

N-Heterocyclic Carbene-Catalysed Diastereoselective Vinylogous Michael Addition Reaction of gamma-Substituted deconjugated Butenolides

KAUST Repository

Guo, Hao

2015-11-16

An efficient N-heterocyclic carbene (NHC)-catalysed vinylogous Michael addition of deconjugated butenolides was developed. In the presence of 5 mol% of the NHC catalyst, both γ-alkyl and aryl-substituted deconjugated butenolides undergo vinylogous Michael addition with various α, β-unsaturated ketones, esters, or nitriles to afford γ,γ-disubstituted butenolides containing adjacent quaternary and tertiary carbon centers in good to excellent yields with excellent diastereoselectivities. In this process, the free carbene is assumed to act as a strong Brønsted base to promote the conjugate addition.

N-Heterocyclic Carbene-Catalysed Diastereoselective Vinylogous Michael Addition Reaction of gamma-Substituted deconjugated Butenolides

KAUST Repository

Guo, Hao; Xing, Fen; Du, Guang-Fen; Huang, Kuo-Wei; Dai, Bin; He, Lin

2015-01-01

An efficient N-heterocyclic carbene (NHC)-catalysed vinylogous Michael addition of deconjugated butenolides was developed. In the presence of 5 mol% of the NHC catalyst, both γ-alkyl and aryl-substituted deconjugated butenolides undergo vinylogous Michael addition with various α, β-unsaturated ketones, esters, or nitriles to afford γ,γ-disubstituted butenolides containing adjacent quaternary and tertiary carbon centers in good to excellent yields with excellent diastereoselectivities. In this process, the free carbene is assumed to act as a strong Brønsted base to promote the conjugate addition.

Virtual screening of electron acceptor materials for organic photovoltaic applications

International Nuclear Information System (INIS)

D Halls, Mathew; Giesen, David J; Goldberg, Alexander; Djurovich, Peter J; Sommer, Jonathan; McAnally, Eric; Thompson, Mark E

2013-01-01

Virtual screening involves the generation of structure libraries, automated analysis to predict properties related to application performance and subsequent screening to identify lead systems and estimate critical structure–property limits across a targeted chemical design space. This approach holds great promise for informing experimental discovery and development efforts for next-generation materials, such as organic semiconductors. In this work, the virtual screening approach is illustrated for nitrogen-substituted pentacene molecules to identify systems for development as electron acceptor materials for use in organic photovoltaic (OPV) devices. A structure library of tetra-azapentacenes (TAPs) was generated by substituting four nitrogens for CH at 12 sites on the pentacene molecular framework. Molecular properties (e.g. E LUMO , E g and μ) were computed for each candidate structure using hybrid DFT at the B3LYP/6-311G** level of theory. The resulting TAPs library was then analyzed with respect to intrinsic properties associated with OPV acceptor performance. Marcus reorganization energies for charge transport for the most favorable TAP candidates were then calculated to further determine suitability as OPV electron acceptors. The synthesis, characterization and OPV device testing of TAP materials is underway, guided by these results. (paper)

Lipase-catalyzed biodiesel synthesis with different acyl acceptors

Directory of Open Access Journals (Sweden)

Ognjanović Nevena D.

2008-01-01

Full Text Available Biodiesel is an alternative fuel for diesel engine that is environmentally acceptable. Conventionally, biodiesel is produced by transesterification of triglycerides and short alcohols in the presence of an acid or an alkaline catalyst. There are several problems associated with this kind of production that can be resolved by using lipase as the biocatalyst. The aim of the present work was to investigate novel acyl acceptors for biodiesel production. 2-Propanol and n-butanol have a less negative effect on lipase stability, and they also improve low temperature properties of the fuel. However, excess alcohol leads to inactivation of the enzyme, and glycerol, a major byproduct, can block the immobilized enzyme, resulting in low enzymatic activity. This problem was solved by using methyl acetate as acyl acceptor. Triacetylglycerol is produced instead of glycerol, and it has no negative effect on the activity of the lipase.

Effect of annealing on metastable shallow acceptors in Mg-doped GaN layers grown on GaN substrates

OpenAIRE

Pozina, Galia; Hemmingsson, Carl; Paskov, Plamen P.; Bergman, Peder; Monemar, Bo; Kawashima, T.; Amano, H.; Akasaki, I.; Usui, A.

2008-01-01

Mg-doped GaN layers grown by metal-organic vapor phase epitaxy on GaN substrates produced by the halide vapor phase technique demonstrate metastability of the near-band-gap photoluminescence (PL). The acceptor bound exciton (ABE) line possibly related to the C acceptor vanishes in as-grown samples within a few minutes under UV laser illumination. Annealing activates the more stable Mg acceptors and passivates C acceptors. Consequently, only the ABE line related to Mg is dominant in PL spectra...

Developments in the chemistry and band gap engineering of donor-acceptor substituted conjugated polymers

NARCIS (Netherlands)

Mullekom, van H.A.M.; Vekemans, J.A.J.M.; Havinga, E.E.; Meijer, E.W.

2001-01-01

This paper reviews the tools to manipulate and minimize the band gap of conjugated (co)polymers. The effects of minimization of the bond length alternation and of the incorporation of donor-K-acceptor units are discussed in particular. A systematic study of a series of alternating donor-acceptor

Shallow acceptors in Ge/GeSi heterostructures with quantum wells in magnetic field

International Nuclear Information System (INIS)

Aleshkin, V.Ya.; Antonov, A.V.; Veksler, D.B.; Gavrilenko, V.I.; Erofeeva, I.V.; Ikonnikov, A.V.; Kozlov, D.V.; Spirin, K.E.; Kuznetsov, O.A.

2005-01-01

One investigated both theoretically and experimentally into shallow acceptors in Ge/GeSi heterostructures with quantum wells (QW) in a magnetic field. It is shown that alongside with lines of cyclotron resonance in magnetoabsorption spectra one observes transitions from the ground state of acceptor to the excited ones associated with the Landau levels from the first and the second subbands of dimensional quantization, and resonance caused by ionization of A + -centres. To describe impurity transitions in Ge/GeSi heterostructures with QW in a magnetic field and to interpret the experiment results in detail one uses numerical method of calculation based on expansion of wave function of acceptor in terms of basis of wave functions of holes in QW in the absence of magnetic field [ru

Correlation between LUMO offset of donor/acceptor molecules to an open circuit voltage in bulk heterojunction solar cell

Energy Technology Data Exchange (ETDEWEB)

Mola, Genene Tessema, E-mail: mola@ukzn.ac.za [School of. Chemistry and Physics, University of Kwazulu-Natal, Pietermaritzburg Campus, Private Bag X01, Scottsville 3209 (South Africa); Abera, Newayemedhin [Addis Ababa University, Department of Physics, P.O. BOX 1176, Addis Ababa (Ethiopia)

2014-07-15

The correlation between the open circuit voltage and the LUMO offset of the donor and acceptor polymers in the bulkheterojunction solar cell was studied for three different thiophene derivatives. The HOMO levels of all the polymers in this investigation were chosen to be similar which results in close values of ΔE{sub DA}=E{sub HOMO}{sup D}−E{sub LUMO}{sup A}. However, the measured V{sub oc} was found to be increasing with decreasing value of the LUMO offset that exists between the donor polymer and fullerene.

Differences in gene expression of human xylosyltransferases and determination of acceptor specificities for various proteoglycans

Energy Technology Data Exchange (ETDEWEB)

Roch, Christina; Kuhn, Joachim; Kleesiek, Knut [Institut fuer Laboratoriums- und Transfusionsmedizin, Herz- und Diabeteszentrum NRW, Universitaetsklinik der Ruhr-Universitaet Bochum, 32545 Bad Oeynhausen (Germany); Goetting, Christian, E-mail: cgoetting@hdz-nrw.de [Institut fuer Laboratoriums- und Transfusionsmedizin, Herz- und Diabeteszentrum NRW, Universitaetsklinik der Ruhr-Universitaet Bochum, 32545 Bad Oeynhausen (Germany)

2010-01-01

The xylosyltransferase (XT) isoforms XT-I and XT-II initiate the posttranslational glycosaminoglycan (GAG) synthesis. Here, we determined the relative expression of both isoforms in 33 human cell lines. The majority of tested cell lines showed dominant XYLT2 gene expression, while only in 23132/87, JAR, NCI-H510A and THP-1 was the XT-I mRNA expression higher. Nearly equal expression levels were detected in six cell lines. Additionally, to shed light on putative differences in acceptor specificities the acceptor properties of potential acceptor sequences were determined. Peptides were expressed as glutathione-S-transferase fusion proteins containing putative or known GAG attachment sites of in vivo proteoglycans. Kinetic analysis showed that K{sub m} and V{sub max} values for XT-I mediated xylosylation were slightly higher than those for XT-II, and that XT-I showed a lesser stringency concerning the acceptor sequence. Mutagenesis of the bikunin peptide sequence in the G-S-G attachment site and flanking regions generated potential acceptor molecules. Here, mutations on the N-terminal side and the attachment site were found to be more susceptible to a loss of acceptor function than mutations in the C-terminus. Altogether the known consensus sequence a-a-a-a-G-S-G-a-a/G-a ('a' representing Asp or Glu) for XT-I mediated xylosylation could be approved and additionally extended to apply to XT-II as well.

Educational Implications of Michael Fishbane's "Sacred Attunement: A Jewish Theology"

Science.gov (United States)

Marom, Daniel

2008-01-01

This article posits Michael Fishbane's Judaic scholarship as a prime resource for Jewish education. The link between the two fields can be made through a translation of the theological underpinnings of Fishbane's insights into Judaism to educational purposes and practices. Initial work with Jewish educators on establishing this link encouraged…

On the acceptor-related photoluminescence spectra of GaAs quantum-wire microcrystals: A model calculation

International Nuclear Information System (INIS)

Oliveira, L.E.; Porras Montenegro, N.; Latge, A.

1992-07-01

The acceptor-related photoluminescence spectrum of a GaAs quantum-wire microcrystal is theoretically investigated via a model calculation within the effective-mass approximation, with the acceptor envelope wave functions and binding energies calculated through a variational procedure. Typical theoretical photoluminescence spectra show two peaks associated to transitions from the n = 1 conduction subband electron gas to acceptors at the on-center and on-edge positions in the wire in good agreement with the recent experimental results by Hirum et al. (Appl. Phys. Lett. 59, 431 (1991)). (author). 14 refs, 3 figs

Fluorescent carbon quantum dots synthesized by chemical vapor deposition: An alternative candidate for electron acceptor in polymer solar cells

Science.gov (United States)

Cui, Bo; Yan, Lingpeng; Gu, Huimin; Yang, Yongzhen; Liu, Xuguang; Ma, Chang-Qi; Chen, Yongkang; Jia, Husheng

2018-01-01

Excitation-wavelength-dependent blue-greenish fluorescent carbon quantum dots (CQDs) with graphite structure were synthesized by chemical vapor deposition (CVD) method. In comparison with those synthesized by hydrothermal method (named H-CQDs), C-CQDs have less hydrophilic terminal groups, showing good solubility in common organic solvents. Furthermore, these synthesized C-CQDs show a low LUMO energy level (LUMO = -3.84 eV), which is close to that of phenyl-C61-butyric acid methyl ester (PC61BM, LUMO = -4.01 eV), the most widely used electron acceptor in polymer solar cells. Photoluminescence quenching of the poly(3-hexylthiophene-2,5-diyl):C-CQDs blended film (P3HT:C-CQDs) indicated that a photo-induced charge transfer between P3HT and C-CQDs occurs in such a composite film. Bulk heterojunction solar cells using C-CQDs as electron acceptors or doping materials were fabricated and tested. High fill factors were achieved for these C-CQDs based polymer solar cells, demonstrating that CQDs synthesized by CVD could be alternative to the fullerene derivatives for applying in polymer solar cells.

77 FR 30047 - Notice of Opportunity for Public Comment on Surplus Property Release at Michael J Smith Field...

Science.gov (United States)

2012-05-21

... Comment on Surplus Property Release at Michael J Smith Field, Beaufort, NC AGENCY: Federal Aviation... J Smith Field, be used for aeronautical purposes. DATES: Comments must be received on or before June... property at the Michael J Smith Field. The property consists of one parcel located on the north side of...

profile of intrauterine contraceptive device acceptors at the university

African Journals Online (AJOL)

ANNALS

Conclusion: The acceptors of intrauterine contraceptive devices in our center were ... Conclusion: Les accepteurs de la contraception de substances médicamentenses dans notre centre .... sterilization due to cultural reasons is very low,13 the.

Michael Perelman: An ecological future in view of Marxist Economics (Ⅱ)

Institute of Scientific and Technical Information of China (English)

Ren Xiaomei

2009-01-01

@@ Interviewee profile: Michael Perelman, currently professor of Economics Department of California State University, USA, American economist and economic historian with nearly 20 publications in the field of economics criticism, including Railroading Economics, Manufacturing Discontent, The Perverse Economy, and The Invention of Capitalism.

Michael Faraday on the Learning of Science and Attitudes of Mind.

Science.gov (United States)

Crawford, Elspeth

1998-01-01

Makes use of Michael Faraday's ideas on learning, focusing on his attitudes toward the unknowns of science and the development of an attitude that improves scientific decision making. This approach acknowledges that there is an inner struggle involved in facing unknowns. (DDR)

Hexafluorobenzene: A powerful solvent for a noncovalent stereoselective organocatalytic Michael addition reaction

KAUST Repository

Lattanzi, Alessandra; De Fusco, Claudia; Russo, Alessio; Poater, Albert; Cavallo, Luigi

2012-01-01

A dramatic enhancement of the diastereo- and enantioselectivity in the nitro-Michael addition reaction organocatalysed by a commercially available α,α-l-diaryl prolinol was disclosed when performing the reaction in unconventional hexafluorobenzene

Prints Charles ja prints Michael külastasid Tallinna kirikuid / Allan Tammiku

Index Scriptorium Estoniae

Tammiku, Allan

2001-01-01

Prints Charles külastas 6. novembril Eesti-visiidi ajal Tallinna toomkirikut ja Pühavaimu kirikut, prints Michael viibis Tallinnas 11. novembril eravisiidil, ta külastas toomkirikut, Niguliste ja Pühavaimu kirikut

Molecular design of donor-acceptor dyes for efficient dye-sensitized solar cells I: a DFT study.

Science.gov (United States)

El-Shishtawy, Reda M; Asiri, Abdullah M; Aziz, Saadullah G; Elroby, Shaaban A K

2014-06-01

Dye-sensitized solar cells (DSSCs) have drawn great attention as low cost and high performance alternatives to conventional photovoltaic devices. The molecular design presented in this work is based on the use of pyran type dyes as donor based on frontier molecular orbitals (FMO) and theoretical UV-visible spectra in combination with squaraine type dyes as an acceptor. Density functional theory has been used to investigate several derivatives of pyran type dyes for a better dye design based on optimization of absorption, regeneration, and recombination processes in gas phase. The frontier molecular orbital (FMO) of the HOMO and LUMO energy levels plays an important role in the efficiency of DSSCs. These energies contribute to the generation of exciton, charge transfer, dissociation and exciton recombination. The computations of the geometries and electronic structures for the predicted dyes were performed using the B3LYP/6-31+G** level of theory. The FMO energies (EHOMO, ELUMO) of the studied dyes are calculated and analyzed in the terms of the UV-visible absorption spectra, which have been examined using time-dependent density functional theory (TD-DFT) techniques. This study examined absorption properties of pyran based on theoretical UV-visible absorption spectra, with comparisons between TD-DFT using B3LYP, PBE, and TPSSH functionals with 6-31+G (d) and 6-311++G** basis sets. The results provide a valuable guide for the design of donor-acceptor (D-A) dyes with high molar absorptivity and current conversion in DSSCs. The theoretical results indicated 4-(dicyanomethylene)-2-methyl-6-(p-dimethylaminostyryl)-4H-pyran dye (D2-Me) can be effectively used as a donor dye for DSSCs. This dye has a low energy gap by itself and a high energy gap with squaraine acceptor type dye, the design that reduces the recombination and improves the photocurrent generation in solar cell.

Der Wert von Worten. Michael Serrer aus dem Literaturbüro Düsseldorf im Interview mit der Textpraxis-Redaktion

Directory of Open Access Journals (Sweden)

Michael Serrer

2014-11-01

Full Text Available Die Textpraxis-Redaktion unterhält sich mit Michael Serrer über Literaturvermittlung in Zeiten der Digitalisierung, über Kanonisierung und die Rolle der Literatur in der Gesellschaft. Michael Serrer ist Leiter des Literaturbüros NRW und Feuilletonist.

Förster Resonance Energy Transfer between Quantum Dot Donors and Quantum Dot Acceptors

Science.gov (United States)

Chou, Kenny F.; Dennis, Allison M.

2015-01-01

Förster (or fluorescence) resonance energy transfer amongst semiconductor quantum dots (QDs) is reviewed, with particular interest in biosensing applications. The unique optical properties of QDs provide certain advantages and also specific challenges with regards to sensor design, compared to other FRET systems. The brightness and photostability of QDs make them attractive for highly sensitive sensing and long-term, repetitive imaging applications, respectively, but the overlapping donor and acceptor excitation signals that arise when QDs serve as both the donor and acceptor lead to high background signals from direct excitation of the acceptor. The fundamentals of FRET within a nominally homogeneous QD population as well as energy transfer between two distinct colors of QDs are discussed. Examples of successful sensors are highlighted, as is cascading FRET, which can be used for solar harvesting. PMID:26057041

Clean and Green Synthesis of New Benzothiazole Derivatives via Electrochemical Oxidation of Catechol Derivatives

Directory of Open Access Journals (Sweden)

Mansour Arab Chamjangali

2016-06-01

Full Text Available Electrochemical oxidation of the catechols 1a and 1b is studied in the presence of 6-methyl-2-thouracil (3b and 6-propyl-2-thiouracil (3a as nucleophiles in a phosphate buffer (0.15 mol L−1, pH = 6.8/DMF (95:5 solution using cyclic voltammetry and controlled-potential coulometry. The results obtained indicate that the quinones derived from the catechols participate in 1,4-Michael-addition reactions with the nucleophiles to form the corresponding new benzothiazole compounds. In this work, we derive a variety of products with good yields using controlled potential at graphite electrodes in an undivided cell. This work is licensed under a Creative Commons Attribution 4.0 International License.

Passings to note: Paul Michael Packman, MD; S. Charles Schulz, MD.

Science.gov (United States)

Black, Donald W

2018-02-01

One of the keys to the success of Annals of Clinical Psychiatry has always been the tireless efforts of our dedicated Editorial Board. We recently lost 2 longtime Editorial Board members, Drs. Paul Michael Packman and S. Charles Schulz. Both will be greatly missed.

Reports of the working groups / Eino Tamm, Sahlin Michael, Valve Kirsipuu...[jt.

Index Scriptorium Estoniae

1999-01-01

Töögruppide "EU enlargement and relevant institutional reforms" (juhatajad Eino Tamm, Michael Sahlin) ja "Maintaining of competitiveness of Estonia and other candidate countries" (juhatajad Valve Kirsipuu, Terry Calbom) tööst. Autor: Reformierakond

Deep and shallow acceptor levels in solid solutions Pb0.98Sm0.02S

International Nuclear Information System (INIS)

Hasanov, H.A.; Rahimov, R.Sh.

2010-01-01

It is well known that the metal vacancies the energy levels of which take place between permitted energies of valency band, are the main acceptor centers in the led salts and solid solutions on their base. The aim of the given paper is founding of character of acceptor levels in single crystals Pb 0 .98Sm 0 .02S with low concentrations of charge carrier. The deep and shallow acceptor levels are found at investigation of Hall effect in Pb 0 .98Sm 0 .02S solid solution with character of low concentrations of charge carriers in crystals

Acceptor number-dependent ultrafast photo-physical properties of push-pull chromophores using time-resolved methods

Science.gov (United States)

Chi, Xiao-Chun; Wang, Ying-Hui; Gao, Yu; Sui, Ning; Zhang, Li-Quan; Wang, Wen-Yan; Lu, Ran; Ji, Wen-Yu; Yang, Yan-Qiang; Zhang, Han-Zhuang

2018-04-01

Three push-pull chromophores comprising a triphenylamine (TPA) as electron-donating moiety and functionalized β-diketones as electron acceptor units are studied by various spectroscopic techniques. The time-correlated single-photon counting data shows that increasing the number of electron acceptor units accelerates photoluminescence relaxation rate of compounds. Transient spectra data shows that intramolecular charge transfer (ICT) takes place from TPA units to β-diketones units after photo-excitation. Increasing the number of electron acceptor units would prolong the generation process of ICT state, and accelerate the excited molecule reorganization process and the relaxation process of ICT state.

Amine donor and acceptor influence on the thermodynamics of ω-transaminase reactions

DEFF Research Database (Denmark)

Gundersen, Maria T.; Abu, Rohana; Schürmann, Martin

2015-01-01

In recent years biocatalytic transamination using ω-transaminase has become established as one of the most interesting routes to synthesize chiral amines with a high enantiomeric purity, especially in the pharmaceutical sector where the demand for such compounds is high. Nevertheless, one limitat...... of such reactions because it may be used to help select suitable donor/acceptor combinations. The results presented here give guidance, with respect to thermodynamics, in order to further extend the application of biocatalytic transamination....... limitation for successful implementation and scale-up is that the thermodynamics of such conversions are frequently found unfavourable. Herein we report experimental measurements of apparent equilibrium constants for several industrially relevant transamination reactions in a systematic manner to better...... understand the effect of amine acceptor and donor choice. For example, we have found that ortho-substitution of acetophenone like molecules, had a significant impact on the thermodynamic equilibrium. Likewise, the effect of cyclic amine acceptors was evaluated and compared to similar non-cyclic structures...

Study of microbial perchlorate reduction: Considering of multiple pH, electron acceptors and donors

Energy Technology Data Exchange (ETDEWEB)

Xu, Xing [Key Laboratory of Water Pollution Control and Recycling (Shandong), School of Environmental Science and Engineering, Shandong University, Jinan 250100 (China); Gao, Baoyu, E-mail: bygao@sdu.edu.cn [Key Laboratory of Water Pollution Control and Recycling (Shandong), School of Environmental Science and Engineering, Shandong University, Jinan 250100 (China); Jin, Bo [School of Chemical Engineering, The University of Adelaide, Adelaide SA 5005,Australia (Australia); Zhen, Hu [Key Laboratory of Water Pollution Control and Recycling (Shandong), School of Environmental Science and Engineering, Shandong University, Jinan 250100 (China); Wang, Xiaoyi [CSIRO Land and Water, Gate 5, Waite Road, Urrbrae, SA 5064 (Australia); Dai, Ming [School of Chemical Engineering, The University of Adelaide, Adelaide SA 5005,Australia (Australia)

2015-03-21

Graphical abstract: Schemes of perchlorate reduction in ClO{sub 4}{sup −}/ClO{sub 3}{sup −}–NO{sub 3}{sup −} e{sup −}acceptor systems. - Highlights: • We created a multiple electron acceptor/donor system for ClO{sub 4}{sup −} reduction. • Nitrate reduction was inhibited when using perchlorate-grown Azospira sp. KJ. • Reduction proceeded as an order of ClO{sub 3}{sup −}, ClO{sub 4}{sup −}and NO{sub 3}{sup −}. • Oxidation of acetate was inhibited by succinate in acetate–succinate series. - Abstract: Bioremediation of perchlorate-cotaminated water by a heterotrophic perchlorate reducing bacterium creates a multiple electron acceptor-donor system. We experimentally determined the perchlorate reduction by Azospira sp. KJ at multiple pH, electron acceptors and donors systems; this was the aim of this study. Perchlorate reduction was drastically inhibited at the pH 6.0, and the maximum reduction of perchlorate by Azospira sp. KJ was observed at pH value of 8.0. Perchlorate reduction was retarded in ClO{sub 4}{sup −}–ClO{sub 3}{sup −}, ClO{sub 4}{sup −}–ClO{sub 3}{sup −}–NO{sub 3}{sup −},and ClO{sub 4}{sup −}–NO{sub 3}{sup −} acceptor systems, while being completely inhibited by the additional O{sub 2} in the ClO{sub 4}{sup −}–O{sub 2} acceptor system. The reduction proceeded as an order of ClO{sub 3}{sup −}, ClO{sub 4}{sup −}, and NO{sub 3}{sup −} in the ClO{sub 4}{sup −}–ClO{sub 3}{sup −}–NO{sub 3}{sup −} system. K{sub S,}v{sub max}, and q{sub max} obtained at different e{sup −} acceptor and donor conditions are calculated as 140.5–190.6 mg/L, 8.7–13.2 mg-perchlorate/L-h, and 0.094–0.16 mg-perchlorate/mg-DW-h, respectively.

Joseph and Michael Haydn in the Bohemian music archives. An anniversary tribute

Czech Academy of Sciences Publication Activity Database

Freemanová, Michaela

2012-01-01

Roč. 20, č. 1 (2012), s. 117-126. ISBN 978-3-486-58949-8. ISSN 1865-5696 Institutional support: RVO:68378076 Keywords : Joseph Haydn * Michael Haydn * music archives Subject RIV: AL - Art, Architecture, Cultural Heritage

Entretien avec Michael Quinn Patton | CRDI - Centre de recherches ...

International Development Research Centre (IDRC) Digital Library (Canada)

9 févr. 2011 ... Michael Quinn Patton, évaluateur de renommée internationale, était récemment au CRDI .... C'est un mode de pensée analytique qui doit tout imprégner. ... des données solides et crédibles sur ce qui marche et ce qui ne marche pas. ... des emplois, des infrastructures et un accès à la nourriture et aux mar.

Charge transfer complex studies between some non-steroidal anti-inflammatory drugs and π-electron acceptors

Science.gov (United States)

Duymus, Hulya; Arslan, Mustafa; Kucukislamoglu, Mustafa; Zengin, Mustafa

2006-12-01

Charge transfer (CT) complexes of some non-steroidal anti-inflammatory drugs, naproxen and etodolac which are electron donors with some π-acceptors, such as tetracyanoethylene (TCNE), 2,3-dichloro-5,6-dicyano- p-benzoquinone (DDQ), p-chloranil ( p-CHL), have been investigated spectrophotometrically in chloroform at 21 °C. The coloured products are measured spectrophotometrically at different wavelength depending on the electronic transition between donors and acceptors. Beer's law is obeyed and colours were produced in non-aqueous media. All complexes were stable at least 2 h except for etodolac with DDQ stable for 5 min. The equilibrium constants of the CT complexes were determined by the Benesi-Hildebrand equation. The thermodynamic parameters Δ H, Δ S, Δ G° were calculated by Van't Hoff equation. Stochiometries of the complexes formed between donors and acceptors were defined by the Job's method of the continuous variation and found in 1:1 complexation with donor and acceptor at the maximum absorption bands in all cases.

Electro-optical and charge injection investigations of the donor-π-acceptor triphenylamine, oligocene–thiophene–pyrimidine and cyanoacetic acid based multifunctional dyes

Directory of Open Access Journals (Sweden)

Ahmad Irfan

2015-10-01

Full Text Available The corner stone of present study is to tune the electro-optical and charge transport properties of donor-bridge-acceptor (D-π-A triphenylamine (TPA derivatives. In the present investigation, an electron deficient moiety (pyrimidine, electron-rich moiety (thiophene and oligocene (benzene, naphthalene, anthracene, tetracene and pentacene have been incorporated as π-spacer between the donor TPA unit and cyanoacetic acid acceptor and anchoring group. The elongation of bridge usually affects the energy levels, i.e., higher the highest occupied molecular orbital (HOMO while lower the lowest unoccupied molecular orbital (LUMO thus reduces the HOMO–LUMO energy gap. The lowered LUMO energy levels of cyano-{2-[6-(4-diphenylamino-phenyl-pyrimidin-4-yl]-tetraceno[2,3-b]thiophen-8-yl}-acetic acid (TPA-PTT4 and cyano-{2-[6-(4-diphenylamino-phenyl-pyrimidin-4-yl]-pentaceno[2,3-b]thiophen-9-yl}-acetic acid (TPA-PPT5 dyes revealed that electron injected from dye to semiconductor surface might be auxiliary stable resulting in impediment of quenching. The broken co-planarity between the π-spacer conceiving LUMO and the TPA moiety would help to impede the recombination process. Moreover, it is expected that TPA derivatives with the tetracenothiophene and pentacenothiophene moieties as π-bridge would show better photovoltaic performance due to lowered LUMO energy level, higher electronic coupling constant, light harvesting efficiency and electron injection values.

Förster Resonance Energy Transfer between Quantum Dot Donors and Quantum Dot Acceptors

Directory of Open Access Journals (Sweden)

Kenny F. Chou

2015-06-01

Full Text Available Förster (or fluorescence resonance energy transfer amongst semiconductor quantum dots (QDs is reviewed, with particular interest in biosensing applications. The unique optical properties of QDs provide certain advantages and also specific challenges with regards to sensor design, compared to other FRET systems. The brightness and photostability of QDs make them attractive for highly sensitive sensing and long-term, repetitive imaging applications, respectively, but the overlapping donor and acceptor excitation signals that arise when QDs serve as both the donor and acceptor lead to high background signals from direct excitation of the acceptor. The fundamentals of FRET within a nominally homogeneous QD population as well as energy transfer between two distinct colors of QDs are discussed. Examples of successful sensors are highlighted, as is cascading FRET, which can be used for solar harvesting.

The power of virtual integration: an interview with Dell Computer's Michael Dell. Interview by Joan Magretta.

Science.gov (United States)

Dell, M

1998-01-01

Michael Dell started his computer company in 1984 with a simple business insight. He could bypass the dealer channel through which personal computers were then being sold and sell directly to customers, building products to order. Dell's direct model eliminated the dealer's markup and the risks associated with carrying large inventories of finished goods. In this interview, Michael Dell provides a detailed description of how his company is pushing that business model one step further, toward what he calls virtual integration. Dell is using technology and information to blur the traditional boundaries in the value chain between suppliers, manufacturers, and customers. The individual pieces of Dell's strategy--customer focus, supplier partnerships, mass customization, just-in-time manufacturing--may be all be familiar. But Michael Dell's business insight into how to combine them is highly innovative. Direct relationships with customers create valuable information, which in turn allows the company to coordinate its entire value chain back through manufacturing to product design. Dell describes how his company has come to achieve this tight coordination without the "drag effect" of ownership. Dell reaps the advantages of being vertically integrated without incurring the costs, all the while achieving the focus, agility, and speed of a virtual organization. As envisioned by Michael Dell, virtual integration may well become a new organizational model for the information age.

Review: Michael Crandall & Karen E. Fisher (Eds) Digital Inclusion: Measuring the Impact of Information and Community Technology

DEFF Research Database (Denmark)

Pors, Niels Ole

2010-01-01

Review: Michael Crandall & Karen E. Fisher (Eds) Digital Inclusion: Measuring the Impact of Information and Community Technology. Medford. Information Today. ASIS&T Monographs, 2009. 185 pages. $ 59.50. ISBN 978-1-57387-373-4......Review: Michael Crandall & Karen E. Fisher (Eds) Digital Inclusion: Measuring the Impact of Information and Community Technology. Medford. Information Today. ASIS&T Monographs, 2009. 185 pages. $ 59.50. ISBN 978-1-57387-373-4...

Michael K. Scullin: Psi Chi/APA Edwin B. Newman Graduate Research Award.

Science.gov (United States)

2011-11-01

Presents Michael K. Scullin as the 2011 winner of the American Psychological Association Psi Chi/APA Edwin B. Newman Graduate Research Award. "For an outstanding research paper that examines the relationship between prospective memory in executing a goal and various lapses of time from 20 minutes up to a 12- hour wake delay and a 12-hour sleep delay. The results suggest that consolidation processes active during sleep increase the probability of goal execution. The paper, titled 'Remembering to Execute a Goal: Sleep On It!' was published in Psychological Science in 2010 and was the basis for Michael K. Scullin's selection as the recipient of the 2011 Psi Chi/APA Edwin B. Newman Graduate Research Award. Mark A. McDaniel, PhD, served as faculty research advisor." (PsycINFO Database Record (c) 2011 APA, all rights reserved). 2011 APA, all rights reserved

Assessment of lipid profile of a group of undergraduates in Michael ...

African Journals Online (AJOL)

Objective: The aim of this study was to measure the lipid fractions in serum blood samples of apparently healthy undergraduates of Michael Okpara University of Agriculture, Umudike. Methods: A total of one hundred consenting males and females aged between 19-30 years were purposively selected from the ...

A celebration of mechanics: from nano to macro. The J. Michael T. Thompson Festschrift issue.

Science.gov (United States)

Elishakoff, Isaac

2013-06-28

This Theme Issue is dedicated to the topic 'Mechanics: from nano to macro' and marks the 75th birthday of Dr J. Michael T. Thompson, Fellow of the Royal Society, whose current affiliations are as follows: (i) Honorary Fellow, Department of Applied Mathematics and Theoretical Physics, Centre for Mathematical Sciences, University of Cambridge; (ii) Emeritus Professor of Nonlinear Dynamics, Department of Civil, Environmental and Geomatic Engineering, University College London; and (iii) Professor of Theoretical and Applied Dynamics (Distinguished Sixth Century Chair, part-time), University of Aberdeen. He also serves as Chairman of the Board of Directors at ES-Consult (consulting engineers) in Copenhagen, Denmark. The pertinent question that arises from the very start is: should we first salute Michael and then describe the Theme Issue, or vice versa? Indeed, according to Blaise Pascal (1623-1662), the last thing one discovers in composing a work is what to put first. I would like to take the liberty of deviating from the tradition of the Philosophical Transactions and start with the tribute to Michael; after all he is the prime cause of this Theme Issue.

Organic charge transfer phase formation in thin films of the BEDT-TTF/TCNQ donor-acceptor system

DEFF Research Database (Denmark)

Solovyeva, Vita; Keller, K.; Huth, M.

2009-01-01

We have performed charge transfer phase formation studies on the donor/acceptor system bis-(ethylendithio)tetrathiafulvalene (BEDT-TTF)/tetracyanoquinodimethane,(TCNQ) by means of physical vapor deposition. We prepared donor/acceptor bilayer structures on glass and Si(100)/SiO substrates held...

The transient reaction characteristic of piperonal and anthraquinone derivative: a pulse radiolytic study

International Nuclear Information System (INIS)

Ma Jianhua; Lin Weizhen; Wang Wenfeng; Yao Side

2006-01-01

Piperonal belongs to naturally organic compound and anthraquinone-2-sulfate is a important anthraquinone derivative. In this work, the transient reaction characteristic of piperonal and anthraquinone derivative has been investigated. The transient absorption spectra of the product from electron transfer reaction between piperonal and anthraquinone-2-sulfate was obtained, the electron transfer between electron donor and acceptor was observed directly. (authors)

Euroopa parimaks filmiks sai Michael Haneke "Valge lint" / Andres Laasik

Index Scriptorium Estoniae

Laasik, Andres, 1960-2016

2009-01-01

Euroopa Filmiakadeemia auhindadest: parima filmiauhinna sai Saksamaal Bochumis toimunud tseremoonial Michael Haneke "Valge lint", mille eest Haneke sai ka parima režissööri ja stsenaristi auhinna. Parimaks meesnäitlejaks pärjati Tahar Rahim ("Un Prophete"), parimaks naisnäitlejaks Kate Winslet ("The Reader"), publikupreemia sai Danny Boyle'i "Rentslimiljonär. Ka teistest võitjatest

Long-Lived Charge Separation at Heterojunctions between Semiconducting Single-Walled Carbon Nanotubes and Perylene Diimide Electron Acceptors

Energy Technology Data Exchange (ETDEWEB)

Kang, Hyun Suk [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Arias, Dylan H [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Blackburn, Jeffrey L [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Sisto, Thomas J. [Columbia University; Peurifoy, Samuel [Columbia University; Zhang, Boyuan [Columbia University; Nuckolls, Colin [Columbia University

2018-04-13

Nonfullerene electron acceptors have facilitated a recent surge in the efficiencies of organic solar cells, although fundamental studies of the nature of exciton dissociation at interfaces with nonfullerene electron acceptors are still relatively sparse. Semiconducting single-walled carbon nanotubes (s-SWCNTs), unique one-dimensional electron donors with molecule-like absorption and highly mobile charges, provide a model system for studying interfacial exciton dissociation. Here, we investigate excited-state photodynamics at the heterojunction between (6,5) s-SWCNTs and two perylene diimide (PDI)-based electron acceptors. Each of the PDI-based acceptors, hPDI2-pyr-hPDI2 and Trip-hPDI2, is deposited onto (6,5) s-SWCNT films to form a heterojunction bilayer. Transient absorption measurements demonstrate that photoinduced hole/electron transfer occurs at the photoexcited bilayer interfaces, producing long-lived separated charges with lifetimes exceeding 1.0 us. Both exciton dissociation and charge recombination occur more slowly for the hPDI2-pyr-hPDI2 bilayer than for the Trip-hPDI2 bilayer. To explain such differences, we discuss the potential roles of the thermodynamic charge transfer driving force available at each interface and the different molecular structure and intermolecular interactions of PDI-based acceptors. Detailed photophysical analysis of these model systems can develop the fundamental understanding of exciton dissociation between organic electron donors and nonfullerene acceptors, which has not been systematically studied.

C. P. Snow's "The Two Cultures": Michael Polanyi's Response and Context

Science.gov (United States)

Jacobs, Struan

2011-01-01

C. P. Snow's "The Two Cultures" controversially contrasted science and literature, suggesting that neither scientists nor literary intellectuals have much in common with, and seldom bother speaking to, the other. Responding to Snow, Michael Polanyi argued that specialization has made modern culture, not twofold but manifold. In his major work,…

Non-Fullerene Electron Acceptors for Use in Organic Solar Cells

KAUST Repository

Nielsen, Christian B.; Holliday, Sarah; Chen, Hung-Yang; Cryer, Samuel J.; McCulloch, Iain

2015-01-01

The active layer in a solution processed organic photovoltaic device comprises a light absorbing electron donor semiconductor, typically a polymer, and an electron accepting fullerene acceptor. Although there has been huge effort targeted

One-Pot Synthesis of 2-Acylindole-3-acetylketones via Domino Aza-alkylation/Michael Reaction Using o-Aminophenyl α,β-Unsaturated Ketones Followed by Desulfonative Dehydrogenation

Energy Technology Data Exchange (ETDEWEB)

Kim, A Reum; Yu, Mi Rim; Sim, Jong Tack; Kim, Sung Gon [Kyonggi Univ., Suwon (Korea, Republic of)

2016-09-15

The development of novel and practical synthetic methods with a minimum number of operations for the construction of bioactive structurally complex compounds is a major challenge in synthetic organic chemistry. Recently, we reported an efficient method for the stereoselective synthesis of 2,3-disubstituted indoline derivatives; cis-2,3-disubstituted indolines were obtained by the aza-alkylation/Michael cascade reaction of 2-(tosylamino)phenyl α,β-unsaturated ketones with α-bromoacetophenones in good yields and with excellent diastereoselectivities (Scheme 2, Eq. (1)). Among the available synthetic strategies, domino or cascade reactions have received wide acceptance as highly efficient and powerful methods for the synthesis of molecules with a high structural complexity. An efficient synthesis of 2,3-disubstituted indoles was developed by the domino aza-alkylation/intramolecular Michael reaction of 2-(tosylamino)phenyl α,β-unsaturated ketones with α-bromoacetophenones, followed by desulfonative dehydrogenation with DBU. The reaction afforded structurally diverse and highly functionalized 2,3-disubstituted indoles in moderate to excellent yields (up to 99%). The synthesis of 2,3-disubstituted indoles without desulfonation through DDQ-induced oxidative dehydrogenation was also achieved.

Modulation of Donor-Acceptor Distance in a Series of Carbazole Push-Pull Dyes; A Spectroscopic and Computational Study

Directory of Open Access Journals (Sweden)

Joshua J. Sutton

2018-02-01

Full Text Available A series of eight carbazole-cyanoacrylate based donor-acceptor dyes were studied. Within the series the influence of modifying the thiophene bridge, linking donor and acceptor and a change in the nature of the acceptor, from acid to ester, was explored. In this joint experimental and computational study we have used electronic absorbance and emission spectroscopies, Raman spectroscopy and computational modeling (density functional theory. From these studies it was found that extending the bridge length allowed the lowest energy transition to be systematically red shifted by 0.12 eV, allowing for limited tuning of the absorption of dyes using this structural motif. Using the aforementioned techniques we demonstrate that this transition is charge transfer in nature. Furthermore, the extent of charge transfer between donor and acceptor decreases with increasing bridge length and the bridge plays a smaller role in electronically mixing with the acceptor as it is extended.

The Physics of Small Molecule Acceptors for Efficient and Stable Bulk Heterojunction Solar Cells

KAUST Repository

Gasparini, Nicola

2018-01-29

Organic bulk heterojunction solar cells based on small molecule acceptors have recently seen a rapid rise in the power conversion efficiency with values exceeding 13%. This impressive achievement has been obtained by simultaneous reduction of voltage and charge recombination losses within this class of materials as compared to fullerene-based solar cells. In this contribution, the authors review the current understanding of the relevant photophysical processes in highly efficient nonfullerene acceptor (NFA) small molecules. Charge generation, recombination, and charge transport is discussed in comparison to fullerene-based composites. Finally, the authors review the superior light and thermal stability of nonfullerene small molecule acceptor based solar cells, and highlight the importance of NFA-based composites that enable devices without early performance loss, thus resembling so-called burn-in free devices.

The Physics of Small Molecule Acceptors for Efficient and Stable Bulk Heterojunction Solar Cells

KAUST Repository

Gasparini, Nicola; Wadsworth, Andrew; Moser, Maximilian; Baran, Derya; McCulloch, Iain; Brabec, Christoph J.

2018-01-01

Organic bulk heterojunction solar cells based on small molecule acceptors have recently seen a rapid rise in the power conversion efficiency with values exceeding 13%. This impressive achievement has been obtained by simultaneous reduction of voltage and charge recombination losses within this class of materials as compared to fullerene-based solar cells. In this contribution, the authors review the current understanding of the relevant photophysical processes in highly efficient nonfullerene acceptor (NFA) small molecules. Charge generation, recombination, and charge transport is discussed in comparison to fullerene-based composites. Finally, the authors review the superior light and thermal stability of nonfullerene small molecule acceptor based solar cells, and highlight the importance of NFA-based composites that enable devices without early performance loss, thus resembling so-called burn-in free devices.

Optimum energy levels and offsets for organic donor/acceptor binary photovoltaic materials and solar cells

International Nuclear Information System (INIS)

Sun, S.-S.

2005-01-01

Optimum frontier orbital energy levels and offsets of an organic donor/acceptor binary type photovoltaic material have been analyzed using classic Marcus electron transfer theory in order to achieve the most efficient photo induced charge separation. This study reveals that, an exciton quenching parameter (EQP) yields one optimum donor/acceptor frontier orbital energy offset that equals the sum of the exciton binding energy and the charge separation reorganization energy, where the photo generated excitons are converted into charges most efficiently. A recombination quenching parameter (RQP) yields a second optimum donor/acceptor energy offset where the ratio of charge separation rate constant over charge recombination rate constant becomes largest. It is desirable that the maximum RQP is coincidence or close to the maximum EQP. A third energy offset is also identified where charge recombination becomes most severe. It is desirable that the most severe charge recombination offset is far away from maximum EQP offset. These findings are very critical for evaluating and fine tuning frontier orbital energy levels of a donor/acceptor pair in order to realize high efficiency organic photovoltaic materials

Hydrogeochemical and stream sediment reconnaissance basic data for St. Michael Quadrangle, Alaska

International Nuclear Information System (INIS)

1981-01-01

Field and laboratory data are presented for 159 water samples from the St. Michael Quadrangle, Alaska. The samples were collected by Los Alamos National Laboratory; laboratory analysis and data reporting were performed by the Uranium Resource Evaluation Project at Oak Ridge, Tennessee

Mechanism of transfer of LDL-derived free cholesterol to HDL subfractions in human plasma

International Nuclear Information System (INIS)

Miida, T.; Fielding, C.J.; Fielding, P.E.

1990-01-01

The transfer of [ 3 H]cholesterol in low-density lipoprotein (LDL) to different high-density lipoprotein (HDL) species in native human plasma was determined by using nondenaturing two-dimensional electrophoresis. Transfer from LDL had a t 1/2 at 37 degree C of 51 ± 8 min and an activation energy of 18.0 kCal mol -1 . There was unexpected specificity among HDL species as acceptors of LDL-derived labeled cholesterol. The largest fraction of the major α-migrating class (HDL 2b ) was the major initial acceptor of LDL-derived cholesterol. Kinetic analysis indicated a rapid secondary transfer from HDL 2b to smaller αHDL (particularly HDL 3 ) driven enzymatically by the lecithin-cholesterol acyltransferase reaction. Rates of transfer among αHDL were most rapid from the largest αHDL fraction (HDL 2b ), suggesting possible protein-mediated facilitation. Simultaneous measurements of the transport of LDL-derived and cell-derived isotopic cholesterol indicated that the former preferably utilized the αHDL pathyway, with little label in pre-βHDL. The same experiments confirmed earlier data that cell-derived cholesterol is preferentially channeled through pre-βHDL. The authors suggest that the functional heterogeneity of HDL demonstrated here includes the ability to independently process cell- and LDL-derived free cholesterol

Astronaut C. Michael Foale is briefed on use of Sky Genie

Science.gov (United States)

1994-01-01

Astronaut C. Michael Foale, STS-63 mission specialist, is briefed on the use of Sky Genie device by Karin L. Porter. The device would aid in emergency egress operations aboard a troubled Space Shuttle. Porter, an employee of Rockwell International, helps train astronauts in egress procedures at JSC's Shuttle mockup and integration laboratory.

Little Mosie from the Margaree: A Biography of Moses Michael Coady.

Science.gov (United States)

Welton, Michael R.

This book examines the life of the Reverend Moses Michael Coady (1890-1959), a Roman Catholic priest who led the Antigonish Movement. During the Antigonish Movement, residents of the small maritime town of Antigonish, Nova Scotia, worked to achieve a nonviolent alternative to communism and fascism and to effect the social and economic…

Effect of cinnamon powder addition during conching on the flavor of dark chocolate mass.

Science.gov (United States)

Albak, F; Tekin, A R

2015-04-01

In the present study, refined dark chocolate mix was conched with the addition of finely powdered cinnamon in a laboratory-style conching machine to evaluate its aroma profile both analytically and sensorially. The analytical determinations were carried out by a combination of solid phase micro extraction (SPME)-gas chromatography (GC)-mass spectroscopy (MS) and-olfactometry(O), while the sensory evaluation was made with trained panelists. The optimum conditions for the SPME were found to be CAR/PDMS as the fiber, 60 °C as the temperature, and 60 min as the time. SPME analyses were carried out at 60 °C for 60 min with toluene as an internal standard. 26 compounds were monitored before and after conching. The unconched sample had a significantly higher fruity odor value than the conched sample. This new product was highly acceptable according to the overall inclination test. However some of textural properties, such as coarseness, and hardness were below the general preference.

FRET two-hybrid assay by linearly fitting FRET efficiency to concentration ratio between acceptor and donor

Science.gov (United States)

Du, Mengyan; Yang, Fangfang; Mai, Zihao; Qu, Wenfeng; Lin, Fangrui; Wei, Lichun; Chen, Tongsheng

2018-04-01

We here introduce a fluorescence resonance energy transfer (FRET) two-hybrid assay method to measure the maximal donor(D)- and acceptor(A)-centric FRET efficiency (ED,max and EA,max) of the D-A complex and its stoichiometry by linearly fitting the donor-centric FRET efficiency (ED) to the acceptor-to-donor concentration ratio (RC) and acceptor-centric FRET efficiency (EA) to 1/RC, respectively. We performed this method on a wide-field fluorescence microscope for living HepG2 cells co-expressing FRET tandem constructs and free donor/acceptor and obtained correct ED, EA, and stoichiometry values of those tandem constructs. Evaluation on the binding of Bad with Bcl-XL in Hela cells showed that Bad interacted strongly with Bcl-XL to form a Bad-Bcl-XL complex on mitochondria, and one Bad interacted mainly with one Bcl-XL molecule in healthy cells, while with multiple (maybe 2) Bcl-XL molecules in apoptotic cells.

Acceptor Type Vacancy Complexes In As-Grown ZnO

International Nuclear Information System (INIS)

Zubiaga, A.; Tuomisto, F.; Zuniga-Perez, J.

2010-01-01

One of the many technological areas that ZnO is interesting for is the construction of opto-electronic devices working in the blue-UV range as its large band gap (∼3.4 eV at 10 K) makes them suitable for that purpose. As-grown ZnO shows generally n-type conductivity partially due to the large concentration of unintentional shallow donors, like H, but impurities can also form complexes with acceptor type defects (Zn vacancy) leading to the creation of compensating defects. Recently, Li Zn and Na Zn acceptors have been measured and H could form similar type of defects. Doppler Broadening Positron Annihilation spectroscopy experimental results on the observation of Zn related vacancy complexes in ZnO thin films, as-grown, O implanted and Al doped will be presented. Results show that as-grown ZnO film show small Zn vacancy related complexed that could be related to presence of H as a unintentional doping element.

Acceptor Type Vacancy Complexes In As-Grown ZnO

Science.gov (United States)

Zubiaga, A.; Tuomisto, F.; Zuñiga-Pérez, J.

2010-11-01

One of the many technological areas that ZnO is interesting for is the construction of opto-electronic devices working in the blue-UV range as its large band gap (˜3.4 eV at 10 K) makes them suitable for that purpose. As-grown ZnO shows generally n-type conductivity partially due to the large concentration of unintentional shallow donors, like H, but impurities can also form complexes with acceptor type defects (Zn vacancy) leading to the creation of compensating defects. Recently, LiZn and NaZn acceptors have been measured and H could form similar type of defects. Doppler Broadening Positron Annihilation spectroscopy experimental results on the observation of Zn related vacancy complexes in ZnO thin films, as-grown, O implanted and Al doped will be presented. Results show that as-grown ZnO film show small Zn vacancy related complexed that could be related to presence of H as a unintentional doping element.

Moral Education and Education in Altruism: Two Replies to Michael Hand

Science.gov (United States)

White, John

2016-01-01

This article is a critical discussion of two recent papers by Michael Hand on moral education. The first is his "Towards a Theory of Moral Education", published in the "Journal of Philosophy of Education" in 2014 (Volume 48, Issue 4). The second is a chapter called "Beyond Moral Education?" in an edited book of new…

A Critical Analysis of Michael Tippett's "A Child of Our Time"

Science.gov (United States)

Vallee, Jean-Sebastien

2009-01-01

After more than ten years of thoughtful planning, Michael Tippett (1905-1998) summed up his musical, political, spiritual and philosophical beliefs in his first oratorio, "A Child of Our Time" (1941). Representing the emergence of a new level of confidence and musical maturity for Tippett, the oratorio has become the composer's most widely known…

Gulliver's Travels: Michael Moore the Explorer in "Who to Invade Next"

Science.gov (United States)

Beck, Bernard

2016-01-01

America is identified as a nation of immigrants. These immigrants are thought to be the source of its subcultures. It is also a nation of individual explorers and inventors. Their activities are also a source of diverse subcultures. Many notable movies have made heroes of such innovators in different fields of endeavor. Michael Moore's movie…

An Interview with Michael Horn: Blending Education for High-Octane Motivation

Science.gov (United States)

Patterson, Gregory A.

2012-01-01

Blended learning holds the potential of improving the way we educate students and of making them more motivated. Blended education--the melding of information technology based distance learning with school attendance--is perhaps the best way to educate students for 21st century skills, says Michael Horn in a "Kappan" interview. Horn points out…

Interplay of alternative conjugated pathways and steric interactions on the electronic and optical properties of donor-acceptor conjugated polymers

KAUST Repository

Lima, Igo T.; Risko, Chad; Aziz, Saadullah Gary; Da Silva Filho, Demé trio A Da Silva; Bredas, Jean-Luc

2014-01-01

Donor-acceptor π-conjugated copolymers are of interest for a wide range of electronic applications, including field-effect transistors and solar cells. Here, we present a density functional theory (DFT) study of the impact of varying the conjugation pathway on the geometric, electronic, and optical properties of donor-acceptor systems. We consider both linear ("in series"), traditional conjugation among the donor-acceptor moieties versus structures where the acceptor units are appended orthogonally to the linear, donor-only conjugated backbone. Long-range-corrected hybrid functionals are used in the investigation with the values of the tuned long-range separation parameters providing an estimate of the extent of conjugation as a function of the oligomer architecture. Considerable differences in the electronic and optical properties are determined as a function of the nature of the conjugation pathway, features that should be taken into account in the design of donor-acceptor copolymers.

Utilization of cinnamon Cinnamomum burmannii leaves and shrimp head in the feed on growth performance of catfish Pangasianodon hypopthalmus

Directory of Open Access Journals (Sweden)

Suclyadi Dairun

2018-06-01

Full Text Available ABSTRACTCatfish farming has confronted with the problem of slow growth to reach the fillet size and less tender of fish fillets. This study aimed to investigate the effect of cinnamon leaf flour and shrimp head flour in formulated diets on growth of catfish Pangasianodon hypopthalamus. Catfish with an initial weight of 207.04 ± 2.70 g/fish reared in 12 cages with a dimension of  2×1×1.5 m3 (L×W×H  and its fish density was 15 fishes for 60 days. Fish were fed with following experimental diets: (1 Control; (2 cinnamon leaf (1% (CL; (3 45% of protein source from shrimp head (SH; (4 CL+SH mix.  The fishes fed twice a day with feeding rate 3.5% of fish biomass. The study found that the use of cinnamon leaf and shrimp head increased the specific growth rate 1.67-1.70%, the feed efficiency 57.55-57.67%, and protein retention 55.61% compared to its control (P<0.05. Triglyceride level, cholesterol, and blood HDL were 416.00-524.05 mg/dL, 139.65-156.68 mg/dL, 73.18-103.70 mg/dL (P>0.05, respectively. HSI value ranged between 0.3-1.9% compared to its control (P<0.05.Keywords: Cinnamomum burmannii, feed, growth, Pangasianodon hypopthalmus, shrimp head.  ABSTRAKBudidaya ikan patin dihadapkan pada permasalahan pertumbuhan dan kualitas daging yaitu pertumbuhan yang lambat untuk mencapai ukuran fillet serta tekstur daging kurang kompak. Tujuan penelitian ini adalah untuk menguji pengaruh penggunaan tepung daun kayu manis dan tepung kepala udang dalam pakan terhadap pertumbuhan ikan patin Pangasianodon hypopthalmus. Ikan patin dengan bobot 207,04 ± 2,70 g/ekordipelihara selama 60 hari di hapa sebanyak 12 buah (berukuran 2×1×1,5 m3dengan padat tebar 15 ekor/jaring. Ikan diberi pakan perlakuan yang terdiri dari: (1 Kontrol; (2 daun kayu manis 1% (DKM; (3 45% sumber protein dari kepala udang (TKU; dan (4 campuran DKM+TKU. Pemberian pakan sebanyak 2 kali sehari dengan feeding rate 3,5% dari biomassa ikan. Hasil dari penelitian penggunaan daun kayu manis

Tandem Michael addition/radical cyclizations for the construction of highly functionalized cyclopentanes

Czech Academy of Sciences Publication Activity Database

Holan, Martin; Pohl, Radek; Císarová, I.; Jahn, Ullrich

2012-01-01

Roč. 106, - (2012), s1298-s1298 ISSN 0009-2770. [EuCheMS Chemistry Congress /4./. 26.08.2012-30.08.2012, Prague] Institutional research plan: CEZ:AV0Z40550506 Keywords : cyclization * diastereoselectivity * Michael addiction * radical reactions * domino reactions Subject RIV: CC - Organic Chemistry

An efficient oxa-Michael addition to diethyl vinylphosphonate under mild reaction conditions

Czech Academy of Sciences Publication Activity Database

Baszczyňski, Ondřej; Jansa, Petr; Dračínský, Martin; Kaiser, Martin Maxmilian; Špaček, Petr; Janeba, Zlatko

2012-01-01

Roč. 2, č. 4 (2012), s. 1282-1284 ISSN 2046-2069 R&D Projects: GA MV VG20102015046 Institutional research plan: CEZ:AV0Z40550506 Keywords : oxa-Michael addition * secondary alcohols * diethyl vinylphosphonate Subject RIV: CC - Organic Chemistry Impact factor: 2.562, year: 2012

Q & A with Ed Tech Leaders: Interview with Michael W. Allen

Science.gov (United States)

Shaughnessy, Michael F.

2014-01-01

Michael W. Allen, the Chairman and CEO of Allen Interactions, is an architect of interactive multimedia learning and is recognized for his many insights, inventions, and presentations. With over 50 years of experience in e-learning, both in academic and corporate settings, he is known for his role in creating Authorware and overseeing the work of…

Michael Polanyi and his generation origins of the social construction of science

CERN Document Server

Nye, Mary Jo

2011-01-01

In Michael Polanyi and His Generation, Mary Jo Nye investigates the role that Michael Polanyi and several of his contemporaries played in the emergence of the social turn in the philosophy of science. This turn involved seeing science as a socially based enterprise that does not rely on empiricism and reason alone but on social communities, behavioral norms, and personal commitments. Nye argues that the roots of the social turn are to be found in the scientific culture and political events of Europe in the 1930s, when scientific intellectuals struggled to defend the universal status of scientific knowledge and to justify public support for science in an era of economic catastrophe, Stalinism and Fascism, and increased demands for applications of science to industry and social welfare. At the center of this struggle was Polanyi, who Nye contends was one of the first advocates of this new conception of science. Nye reconstructs Polanyi’s scientific and political milieus in Budapest, Berlin, and Manchester f...

Bane of Hydrogen-Bond Formation on the Photoinduced Charge-Transfer Process in Donor–Acceptor Systems

KAUST Repository

Alsam, Amani Abdu

2017-03-14

Controlling the ultrafast dynamical process of photoinduced charge transfer at donor acceptor interfaces remains a major challenge for physical chemistry and solar cell communities. The process is complicated by the involvement of other complex dynamical processes, including hydrogen bond formation, energy transfer, and solvation dynamics occurring on similar time scales. In this study, we explore the remarkable impact of hydrogen-bond formation on the interfacial charge transfer between a negatively charged electron donating anionic porphyrin and a positively charged electron accepting pi-conjugated polymer, as a model system in solvents with different polarities and capabilities for hydiogen bonding using femtosecond transient absorption spectroscopy. Unlike the conventional understanding of the key role of hydrogen bonding in promoting the charge-transfer process, our steadystate and time-resolved results reveal that the intervening hydrogen-bonding environment and, consequently, the probable longer spacing between the donor and acceptor molecules significantly hinders the charge-transfer process between them. These results show that site-specific hydrogen bonding and geometric considerations between donor and acceptor can be exploited to control both the charge-transfer dynamics and its efficiency not only at donor acceptor interfaces but also in complex biological systems.

Identification of Ag-acceptors in $^{111}Ag^{111}Cd$ doped ZnTe and CdTe

CERN Document Server

Hamann, J; Deicher, M; Filz, T; Lany, S; Ostheimer, V; Strasser, F; Wolf, H; Wichert, T

2000-01-01

Nominally undoped ZnTe and CdTe crystals were implanted with radioactive /sup 111/Ag, which decays to /sup 111/Cd, and investigated by photoluminescence spectroscopy (PL). In ZnTe, the PL lines caused by an acceptor level at 121 meV are observed: the principal bound exciton (PBE) line, the donor-acceptor pair (DAP) band, and the two-hole transition lines. In CdTe, the PBE line and the DAP band that correspond to an acceptor level at 108 meV appear. Since the intensities of all these PL lines decrease in good agreement with the half-life of /sup 111/Ag of 178.8 h, both acceptor levels are concluded to be associated with defects containing a single Ag atom. Therefore, the earlier assignments to substitutional Ag on Zn- and Cd-lattice sites in the respective II-VI semiconductors are confirmed. The assignments in the literature of the S/sub 1/, S /sub 2/, and S/sub 3/ lines in ZnTe and the X/sub 1//sup Ag/, X/sub 2 //sup Ag//C/sub 1//sup Ag/, and C/sub 2//sup Ag/ lines in CdTe to Ag- related defect complexes are ...

Discriminating a deep defect from shallow acceptors in supercell calculations: gallium antisite in GaAs

Science.gov (United States)

Schultz, Peter

To make reliable first principles predictions of defect energies in semiconductors, it is crucial to discriminate between effective-mass-like defects--for which existing supercell methods fail--and deep defects--for which density functional theory calculations can yield reliable predictions of defect energy levels. The gallium antisite GaAs is often associated with the 78/203 meV shallow double acceptor in Ga-rich gallium arsenide. Within a framework of level occupation patterns, analyses of structure and spin stabilization can be used within a supercell approach to distinguish localized deep defect states from shallow acceptors such as BAs. This systematic analysis determines that the gallium antisite is inconsistent with a shallow state, and cannot be the 78/203 shallow double acceptor. The properties of the Ga antisite in GaAs are described, predicting that the Ga antisite is a deep double acceptor and has two donor states, one of which might be accidentally shallow. -- Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Company, for the U.S. Department of Energy's National Nuclear Security Administration under Contract DE-AC04-94AL85000.

Synthesis and Regioselective Reaction of Some Unsymmetrical Heterocyclic Chalcone Derivatives and Spiro Heterocyclic Compounds as Antibacterial Agents.

Science.gov (United States)

El-Hashash, Maher A; Rizk, Sameh A; Atta-Allah, Saad R

2015-12-10

A number of novel heterocyclic chalcone derivatives can be synthesized by thermal and microwave tools. Treatment of 4-(4-Acetylamino- and/or 4-bromo-phenyl)-4-oxobut-2-enoic acids with hydrogen peroxide in alkaline medium were afforded oxirane derivatives 2. Reaction of the epoxide 2 with 2-amino-5-aryl-1,3,4-thiadiazole derivatives yielded chalcone of imidazo[2,1-b]thiadiazole derivative 4 via two thermal routes. In one pot reaction of 4-bromoacetophenone, diethyloxalate, and 2-amino-5-aryl-1,3,4-thiadiazole derivatives in MW irradiation (W 250 and T 150 °C) under eco-friendly conditions afforded an unsuitable yield of the desired chalcone 4d. The chalcone derivatives 4 were used as a key starting material to synthesize some new spiroheterocyclic compounds via Michael and aza-Michael adducts. The chalcone 4f was similar to the aryl-oxo-vinylamide derivatives for the inhibition of tyrosine kinase and cancer cell growth. The electron-withdrawing substituents, such as halogens, and 2-amino-1,3,4-thiadiazole moeity decreasing the electron density, thereby decreasing the energy of HOMO, and the presence of imidazothiadiazole moiety should improve the antibacterial activity. Thus, the newly synthesized compounds were evaluated for their anti-bacterial activity against (ATCC 25923), (ATCC 10987), (ATCC 274,) and (SM514). The structure of the newly synthesized compounds was confirmed by elemental analysis and spectroscopic data.

Magnetic field effect on the Coulomb interaction of acceptors in semimagnetic quantum dot

Energy Technology Data Exchange (ETDEWEB)

Kalpana, P.; Merwyn, A.; Nithiananthi, P.; Jayakumar, K., E-mail: kjkumar-gri@rediffmail.com [Nanostructure Lab, Department of Physics, Gandhigram Rural University, Gandhigram-624302 (India); Reuben, Jasper D. [Department of Physics, School of Engineering, Saveetha University, Thandalam, Chennai- 600104 (India)

2015-06-24

The Coulomb interaction of holes in a Semimagnetic Cd{sub 1-x}Mn{sub x}Te / CdTe Spherical and Cubical Quantum Dot (SMQD) in a magnetic field is studied using variational approach in the effective mass approximation. Since these holes in QD show a pronounced collective behavior, while distinct single particle phenomena is suppressed, their interaction in confined potential becomes very significant. It has been observed that acceptor-acceptor interaction is more in cubical QD than in spherical QD which can be controlled by the magnetic field. The results are presented and discussed.

Magnetic field effect on the Coulomb interaction of acceptors in semimagnetic quantum dot

Science.gov (United States)

Kalpana, P.; Merwyn, A.; Reuben, Jasper D.; Nithiananthi, P.; Jayakumar, K.

2015-06-01

The Coulomb interaction of holes in a Semimagnetic Cd1-xMnxTe / CdTe Spherical and Cubical Quantum Dot (SMQD) in a magnetic field is studied using variational approach in the effective mass approximation. Since these holes in QD show a pronounced collective behavior, while distinct single particle phenomena is suppressed, their interaction in confined potential becomes very significant. It has been observed that acceptor-acceptor interaction is more in cubical QD than in spherical QD which can be controlled by the magnetic field. The results are presented and discussed.

Interaction of point intrinsic defects in n-type indium phosphide with acceptor clusters

International Nuclear Information System (INIS)

Vitovskij, N.A.; Lagunova, T.S.; Rakhimov, O.

1984-01-01

The rates of implanting defects of donor- and acceptor type stable at room temperature in n-InP during gamma irradiation are found to vary versus the compensating impurity type. Zinc atoms interact with defects most actively. Irradiation also brings about the growth of acceptor clusters, this growth being most markedly expressed in InP . The presence of an additional mechanism of charge-carriers scattering associated with the existence of clusters of compensating centres is verified, the temperature dependence of the effectiveness of this mechanism μ approximately Tsup(-1.2) is found

A spiro-bifluorene based 3D electron acceptor with dicyanovinylene substitution for solution-processed non-fullerene organic solar cells

KAUST Repository

Xia, Debin

2015-04-20

A novel electron acceptor, namely 2,2′-(12H,12′H-10,10′-spirobi[indeno[2,1-b]fluorene]-12,12′-diylidene)dimalononitrile (4CN-spiro), exhibiting a three-dimensional molecular structure was synthesized and its thermal, photophysical, electrochemical, crystal, and photovoltaic properties were investigated. The novel acceptor exhibits excellent thermal stability with a decomposition temperature of 460 °C, an absorption extending to 600 nm, and a LUMO level of −3.63 eV. Solution processed bulk-heterojunction (BHJ) organic solar cells were fabricated using 4CN-spiro as an acceptor and polythieno[3,4-b]-thiophene-co-benzodithiophene (PTB7) as a donor polymer. The effect of the donor-to-acceptor ratio and processing conditions on the device performance was investigated. A device processed from tetrachloroethane with a donor to acceptor weight ratio of 1 : 1 yielded a power conversion efficiency (PCE) of 0.80%.

Medium-Bandgap Small-Molecule Donors Compatible with Both Fullerene and Nonfullerene Acceptors.

Science.gov (United States)

Huo, Yong; Yan, Cenqi; Kan, Bin; Liu, Xiao-Fei; Chen, Li-Chuan; Hu, Chen-Xia; Lau, Tsz-Ki; Lu, Xinhui; Sun, Chun-Lin; Shao, Xiangfeng; Chen, Yongsheng; Zhan, Xiaowei; Zhang, Hao-Li

2018-03-21

Much effort has been devoted to the development of new donor materials for small-molecule organic solar cells due to their inherent advantages of well-defined molecular weight, easy purification, and good reproducibility in photovoltaic performance. Herein, we report two small-molecule donors that are compatible with both fullerene and nonfullerene acceptors. Both molecules consist of an (E)-1,2-di(thiophen-2-yl)ethane-substituted (TVT-substituted) benzo[1,2-b:4,5-b']dithiophene (BDT) as the central unit, and two rhodanine units as the terminal electron-withdrawing groups. The central units are modified with either alkyl side chains (DRBDT-TVT) or alkylthio side chains (DRBDT-STVT). Both molecules exhibit a medium bandgap with complementary absorption and proper energy level offset with typical acceptors like PC 71 BM and IDIC. The optimized devices show a decent power conversion efficiency (PCE) of 6.87% for small-molecule organic solar cells and 6.63% for nonfullerene all small-molecule organic solar cells. Our results reveal that rationally designed medium-bandgap small-molecule donors can be applied in high-performance small-molecule organic solar cells with different types of acceptors.

Book Review: America’s Blind Spot: Chávez, Oil and US Security by Andrés Cala and Michael Economides

DEFF Research Database (Denmark)

Boscan, Luis

2014-01-01

Review of: America’s Blind Spot: Chávez, Oil and US Security. Andrés Cala and Michael Economides. Continuum Books. 2012.......Review of: America’s Blind Spot: Chávez, Oil and US Security. Andrés Cala and Michael Economides. Continuum Books. 2012....

Structural, theoretical and experimental models of photosynthetic antennas, donors and acceptors

International Nuclear Information System (INIS)

Barkigia, K.M.; Chantranupong, L.; Fajer, J.; Kehres, L.A.; Smith, K.M.

1989-01-01

Theoretical calculations, based on recent x-ray studies of bacterial reaction centers, suggest that the light-absorption properties of the special pair phototraps in bacteria are controlled by the interplanar spacing between the bacteriochlorophyll subunits that constitute the special pairs. The calculations offer attractively simple explanations for the range of absorption spectra exhibited by photosynthetic bacteria. The wide range of (bacterio)chlorophyll skeletal conformations revealed by x-ray diffraction studies raise the intriguing possibility that different conformations, imposed by protein constraints, can modulate the light-absorption and redox properties of the chromophores in vivo. Electron-nuclear double resonance data obtained for the primary acceptors in green plants suggest specific substituent orientations and hydrogen bonding that may help optimize the orientations of the acceptors relative to the donors

Mechanism of electron transfer from e-sub(aq) to acceptors in micelles

International Nuclear Information System (INIS)

Graetzel, M.; Henglein, A.; Janata, E.

1975-01-01

Pulse radiolysis experiments were carried out to investigate reactions A + e - sub(aq) → A - of hydrated electrons with acceptors A incorporated in the lipoidic part of micellar 10 -3 M sodium-lauryl-sulfate (SLS) and cetyl-trimethyl-ammonium-bromide (CTAB). The acceptors were 9-nitro-anthracene and pyrene, the latter in both the singlet and triplet state (the triplet was produced by UV-light irradiation shortly before the high energy electron pulse was applied). The triplet state of pyrene reacts in CTAB-micelles with a rate constant smaller by at least a factor of two than the singlet ground state. (orig./HK) [de

Triazole-curcuminoids: A new class of derivatives for 'tuning' curcumin bioactivities?

Science.gov (United States)

Caprioglio, Diego; Torretta, Simone; Ferrari, Maila; Travelli, Cristina; Grolla, Ambra A; Condorelli, Fabrizio; Genazzani, Armando A; Minassi, Alberto

2016-01-15

Curcumin is a unique blend of pharmacophores responsible for the pleiotropy of this natural pigment. In the present study we have replaced the 1,3-dicarbonyl moiety with a 1,2,3-triazole ring to furnish a new class of triazole-curcuminoids as a possible strategy to generate new compounds with different potency and selectivity compared to curcumin. We obtained a proof-of-principle library of 28 compounds tested for their cytotoxicity (SY-SY5Y and HeLa cells) and for their ability to inhibit NF-κB. Furthermore, we also generated 1,3-dicarbonyl curcuminoids of selected click compounds. Triazole-curcuminoids lost their ability to be Michael's acceptors, yet maintained some of the features of the parent compounds and disclosed new ones. In particular, we found that some compounds were able to inhibit NF-κB without showing cytotoxicity, while others, unlike curcumin, activated NF-κB signalling. This validates the hypothesis that click libraries can be used to investigate the biological activities of curcumin as well as generate analogs with selected features. Copyright © 2015 Elsevier Ltd. All rights reserved.

Crystallization and preliminary X-ray diffraction analysis of a tRNASer acceptor-stem microhelix

International Nuclear Information System (INIS)

Förster, Charlotte; Krauss, Norbert; Brauer, Arnd B. E.; Szkaradkiewicz, Karol; Brode, Svenja; Hennig, Klaus; Fürste, Jens P.; Perbandt, Markus; Betzel, Christian; Erdmann, Volker A.

2006-01-01

In order to investigate tRNA identity elements, an elongator tRNA Ser acceptor-stem helix was crystallized and a data set was collected to 1.8 Å resolution aiming at a comparison with the corresponding region in suppressor tRNA Sec . In order to understand elongator tRNA Ser and suppressor tRNA Sec identity elements, the respective acceptor-stem helices have been synthesized and crystallized in order to analyse and compare their structures in detail at high resolution. The synthesis, crystallization and preliminary X-ray diffraction results for a seven-base-pair tRNA Ser acceptor-stem helix are presented here. Diffraction data were collected to 1.8 Å, applying synchrotron radiation and cryogenic cooling. The crystals belong to the monoclinic space group C2, with unit-cell parameters a = 36.14, b = 38.96, c = 30.81 Å, β = 110.69°

Enantio- and Stereoselective Construction of Atisane Scaffold via Organocatalytic Intramolecular Michael Reaction and Diels-Alder Reaction.

Science.gov (United States)

Sekita, Hiroko; Adachi, Kyohei; Kobayashi, Ippei; Sato, Yusuke; Nakada, Masahisa

2017-05-05

An enantio- and stereoselective construction of the atisane scaffold via organocatalytic intramolecular Michael reaction and Diels-Alder reaction is described. The organocatalytic intramolecular Michael reaction has been found to stereoselectively generate a trans-stereodiad comprising an all-carbon quaternary and a tertiary stereogenic centers. Use of the chiral secondary amine bearing thiourea with benzoic acid as additive is the key to obtaining the desired product with excellent ee in synthetically acceptable yield. The prepared chiral building block has been successfully converted to the compound including the atisane scaffold via the highly stereoselective intramolecular Diels-Alder reaction.

Theory and practice in action: the contributions of Michael Perkins to clinical linguistics.

Science.gov (United States)

Damico, Jack S; Lynch, Karen E

2013-01-01

This article reviews the scholarly contributions of Michael R. Perkins in the discipline of clinical linguistics and provides some indication of the reasons that he has been so successful. Three primary attributes were described through an analysis of his publications.

An overview of electron acceptors in microbial fuel cells

DEFF Research Database (Denmark)

Ucar, Deniz; Zhang, Yifeng; Angelidaki, Irini

2017-01-01

Microbial fuel cells (MFC) have recently received increasing attention due to their promising potential in sustainable wastewater treatment and contaminant removal. In general, contaminants can be removed either as an electron donor via microbial catalyzed oxidization at the anode or removed at t...... acceptors (e.g., nitrate, iron, copper, perchlorate) and mediators....

Fused-Ring Acceptors with Asymmetric Side Chains for High-Performance Thick-Film Organic Solar Cells.

Science.gov (United States)

Feng, Shiyu; Zhang, Cai'e; Liu, Yahui; Bi, Zhaozhao; Zhang, Zhe; Xu, Xinjun; Ma, Wei; Bo, Zhishan

2017-11-01

A kind of new fused-ring electron acceptor, IDT-OB, bearing asymmetric side chains, is synthesized for high-efficiency thick-film organic solar cells. The introduction of asymmetric side chains can increase the solubility of acceptor molecules, enable the acceptor molecules to pack closely in a dislocated way, and form favorable phase separation when blended with PBDB-T. As expected, PBDB-T:IDT-OB-based devices exhibit high and balanced hole and electron mobility and give a high power conversion efficiency (PCE) of 10.12%. More importantly, the IDT-OB-based devices are not very sensitive to the film thickness, a PCE of 9.17% can still be obtained even the thickness of active layer is up to 210 nm. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Single and double acceptor-levels of a carbon-hydrogen defect in n-type silicon

Energy Technology Data Exchange (ETDEWEB)

Stübner, R.; Scheffler, L.; Kolkovsky, Vl., E-mail: kolkov@ifpan.edu.pl; Weber, J. [Technische Universität Dresden, 01062 Dresden (Germany)

2016-05-28

In the present study, we discuss the origin of two dominant deep levels (E42 and E262) observed in n-type Si, which is subjected to hydrogenation by wet chemical etching or a dc H-plasma treatment. Their activation enthalpies determined from Laplace deep level transient spectroscopy measurements are E{sub C}-0.06 eV (E42) and E{sub C}-0.51 eV (E262). The similar annealing behavior and identical depth profiles of E42 and E262 correlate them with two different charge states of the same defect. E262 is attributed to a single acceptor state due to the absence of the Poole-Frenkel effect and the lack of a capture barrier for electrons. The emission rate of E42 shows a characteristic enhancement with the electric field, which is consistent with the assignment to a double acceptor state. In samples with different carbon and hydrogen content, the depth profiles of E262 can be explained by a defect with one H-atom and one C-atom. From a comparison with earlier calculations [Andersen et al., Phys. Rev. B 66, 235205 (2002)], we attribute E42 to the double acceptor and E262 to the single acceptor state of the CH{sub 1AB} configuration, where one H atom is directly bound to carbon in the anti-bonding position.

A rhodanine flanked nonfullerene acceptor for solution-processed organic photovoltaics

KAUST Repository

Holliday, Sarah; Ashraf, Raja Shahid; Nielsen, Christian Bergenstof; Kirkus, Mindaugas; Rö hr, Jason A.; Tan, Chinghong; Collado-Fregoso, Elisa; Knall, Astrid Caroline; Durrant, James R.; Nelson, Jenny K.; McCulloch, Iain

2015-01-01

3HT:PC60BM devices, the acceptor does not aggregate enough to create appropriate percolation pathways that prevent fast nongeminate recombination. Despite this nonoptimal morphology the P3HT:FBR devices exhibit better performance than P3HT:PC60BM

Organocatalytic asymmetric michael addition of aldehydes to beta-nitroacroleine dimethyl acetal.

Science.gov (United States)

Reyes, Efraim; Vicario, Jose L; Badía, Dolores; Carrillo, Luisa

2006-12-21

[Structure: see text] The organocatalytic asymmetric Michael addition of aldehydes to beta-nitroacroleine dimethyl acetal has been studied in detail. The reaction took place with excellent yields and high stereoselectivities when a chiral beta-amino alcohol such as L-prolinol was employed as the catalyst, leaving a formation of highly functionalized enantioenriched compounds containing two differentiated formyl groups together with a nitro moiety.

Learned Helplessness Encountered by Michael Oher in the Blind Side Movie

OpenAIRE

PAMUNGKAS, DIMAS PROBO

2014-01-01

Pamungkas, Dimas Probo. 2014. Learned Helplessness Encountered by Michael Oher in The Blind Side Movie. Study Program of English, Department of Languages and Literature, Faculty of Culture Studies, Universitas Brawijaya. Supervisor: Dyah Eko Hapsari;Co-supervisor: Sarlettina Vidyayani EkaKeywords: Learned Helplessness, African-American, Psychological, Social Behavior, Depression, The Blind Side.Social behavior shows several interactions between person and social situations, which stress...

Surface protection during plasma hydrogenation for acceptor passivation in InP

International Nuclear Information System (INIS)

Lopata, J.; Dautremont-Smith, W.C.; Pearton, S.J.; Lee, J.W.; Ha, N.T.; Luftman, H.S.

1990-01-01

Various dielectric and metallic films were examined as H-permeable surface protection layers on InP during H 2 or D 2 plasma exposure for passivation of acceptors in the InP. Plasma deposited SiN x , SiO 2 , and a-Si(H) films ranging in thickness from 85 to 225 angstrom were used to protect p-InP during d 2 plasma exposure at 250 degrees C. Optimum protective layer thicknesses were determined by a trade-off between the effectiveness of the layer to prevent P loss from the wafer surface and the ability to diffuse atomic H or D at a rate greater than or equal to that in the underlying InP. SIMS and capacitance-voltage depth profiling were used to determine the extent of D in-diffusion and acceptor passivation respectively. Sputter deposited W and e-beam evaporated Ti films ∼100 Angstrom thick were also evaluated. The W coated sample yielded similar results to those with dielectric films in that acceptors in p-InP were passivated to a similar depth for the same plasma exposure. The 100 Angstrom Ti film, however, did not allow the D to diffuse into the InP substrate. It is surmised that the Ti film trapped the D, thus preventing diffusion into the substrate

From Gouldner to Gramsci: The Making of Michael Apple's "Ideology and Curriculum"

Science.gov (United States)

Gottesman, Isaac

2012-01-01

Michael Apple's "Ideology and Curriculum", published in 1979, helped initiate a broad turn in the field of education in the United States to Marxist thought as a lens through which to analyze the relationship between school and society. This classic text continues to inform scholarship in the field. While "Ideology" has…

Ultrafast electron transfer in all-carbon-based SWCNT-C60 donor-acceptor nanoensembles connected by poly(phenylene-ethynylene) spacers

Science.gov (United States)

Barrejón, Myriam; Gobeze, Habtom B.; Gómez-Escalonilla, María J.; Fierro, José Luis G.; Zhang, Minfang; Yudasaka, Masako; Iijima, Sumio; D'Souza, Francis; Langa, Fernando

2016-08-01

Building all-carbon based functional materials for light energy harvesting applications could be a solution to tackle and reduce environmental carbon output. However, development of such all-carbon based donor-acceptor hybrids and demonstration of photoinduced charge separation in such nanohybrids is a challenge since in these hybrids part of the carbon material should act as an electron donating or accepting photosensitizer while the second part should fulfil the role of an electron acceptor or donor. In the present work, we have successfully addressed this issue by synthesizing covalently linked all-carbon-based donor-acceptor nanoensembles using single-walled carbon nanotubes (SWCNTs) as the donor and C60 as the acceptor. The donor-acceptor entities in the nanoensembles were connected by phenylene-ethynylene spacer units to achieve better electronic communication and to vary the distance between the components. These novel SWCNT-C60 nanoensembles have been characterized by a number of techniques, including TGA, FT-IR, Raman, AFM, absorbance and electrochemical methods. The moderate number of fullerene addends present on the side-walls of the nanotubes largely preserved the electronic structure of the nanotubes. The thermodynamic feasibility of charge separation in these nanoensembles was established using spectral and electrochemical data. Finally, occurrence of ultrafast electron transfer from the excited nanotubes in these donor-acceptor nanohybrids has been established by femtosecond transient absorption studies, signifying their utility in building light energy harvesting devices.Building all-carbon based functional materials for light energy harvesting applications could be a solution to tackle and reduce environmental carbon output. However, development of such all-carbon based donor-acceptor hybrids and demonstration of photoinduced charge separation in such nanohybrids is a challenge since in these hybrids part of the carbon material should act as an

Navigating Transition: Freedom, Limitation and the Post-colonial Persona in Michael Ondaatje's The Cat's Table

Directory of Open Access Journals (Sweden)

Alaa Alghamdi

2012-11-01

Full Text Available Michael Ondaatje's 2011 novel The Cat's Table follows a young boy's voyage from Colombo, Sri Lanka to London, England. Through this character and the unique environment of the ship, which forms a compelling sense of transitory place, Ondaatje explores liminality and its relationship with limitations or barriers. The young protagonist, Michael, and his companions enjoy an unusual level of freedom aboard the contained and hierarchically segmented ship. Polarization and transition between Eastern and Western culture is present but pales in importance compared to the validation of the self that is located within and defined by the sense of the in-between, an essential rite of passage undertaken before re-joining society.

Making highly conductive ZnO: creating donors and destroying acceptors

Science.gov (United States)

Look, D. C.; Leedy, K. D.

2012-02-01

We obtain room-temperature resistivities as low as ρ =1.4 x 10-4 Ω-cm in transparent Ga-doped ZnO grown on Al2O3 by pulsed laser deposition (PLD) at 200 °C in 10 mTorr of pure Ar and then annealed in a Zn enfivironment. Donor ND and acceptor NA concentrations are calculated from a recently developed scattering theory that is valid for any degenerate semiconductor material and requires only two input parameters, mobility μ and carrier concentration n measured at any temperature in the range 5 - 300 K. By comparison with SIMS and positron annihilation measurements, it has been shown that the donors in these samples are mostly GaZn, as expected, but that the acceptors are point defects, Zn vacancies VZn. PLD growth in Ar at 200 °C produces a high concentration of donors [GaZn] = 1.4 x 1021 cm-3, but VZn acceptors are produced at the same time, due to self-compensation. Fortunately, a large fraction of the VZn can be eliminated by annealing in a Zn environment. The theory gives ND and NA, and thus [GaZn] and [VZn], at each step of the growth and annealing process. For convenience, the theory is presented graphically, as plots of μ vs n at various values of compensation ratio K = NA/ND. From the value of K corresponding to the experimental values of μ and n, it is possible to calculate ND = n/(1 - K) and NA = nK/(1 - K).

Tõsine fotoelamus Dubrovnikus / Wade Goddard, Heidi Levine, Michael Robinson Chaver ; interv. Ahto Külvet

Index Scriptorium Estoniae

Goddard, Wade

2007-01-01

Dubrovniku vanalinnas asub Sõjafotokeskus. Intervjuu keskuse asutaja, kanadalasest fotograafi Wade Goddardi ja kahe seal augustis avatud näitusel osalenud fotograafi Heidi Levine'i ja Michael Robinson Chavez'iga. Sõjafotograafi tööst

The Correspondence of Michael Faraday Pt 6 1860-1867

CERN Document Server

Frank, James

2012-01-01

Michael Faraday (1791-1867) was one of the most important men of science in nineteenth century Britain. His discoveries of electro-magnetic rotations (1821) and electro-magnetic induction (1831) laid the foundations of the modern electrical industry. His discovery of the magneto-optical effect and diamagnetism (1845) led him to formulate the field theory of electro-magnetism, which forms one of the cornerstones of modern physics.These and a whole host of other fundamental discoveries in physics and chemistry, together with his lecturing at the Royal Institution, his work for the state (includi

J-V and C-V investigation of the effect of small molecular fullerene and non-fullerene acceptors for CH3NH3PbI3 perovskite solar cell

Science.gov (United States)

Zheng, Yanqiong; Wang, Chao; Yu, Junle; Yang, Fang; Zhang, Jing; Wei, Bin; Li, Weishi

2017-11-01

To find the ideal acceptors for perovskite solar cells (PSCs) and get insight into the dielectric property at the interface between perovskite and acceptor, series of small molecular fullerene and non-fullerene acceptors were comparatively investigated. Fullerene acceptors based PSCs show higher performance than non-fullerene acceptors based PSCs. However, the perylene tetracarboxylic diimide based PSC has achieved a η PCE of 4.70%, implying that it is a promising acceptor candidate for PSCs because of its suitable energy level, high electron mobility, and smooth surface. By employing double acceptors of (6,6)-phenyl-C61-butyric acid methyl ester (PCBM)/C60 or PCBM/3,4,9,10-perylenetetracarboxylic bisbenzimidazole, the PSC stability is greatly improved even without performance enhancement. The perovskite (Pero)/PCBM film shows smooth surface, suggesting that PCBM penetrates into the Pero layer. The hydrophobicity trend of Pero/acceptor composite films is same as the device performance by judging from the water contact angle, and Pero/PCBM as well as Pero/C60 show higher hydrophobicity than other Pero/small-molecular-acceptor composite films. Capacitance-voltage characteristics of the series of single and double acceptor based PSCs were measured. The double acceptor based PSCs show larger depletion layer width (W d) than single acceptor based PSCs. Meanwhile, the defect density (N A) in Pero layer for single acceptor based PSCs is larger than that for double acceptor based PSCs, implying better n-doping of Pero layer by using a single acceptor.

Anaerobic α-Amylase Production and Secretion with Fumarate as the Final Electron Acceptor in Saccharomyces cerevisiae

DEFF Research Database (Denmark)

Liu, Zihe; Österlund, Tobias; Hou, Jin

2013-01-01

In this study, we focus on production of heterologous α-amylase in the yeast Saccharomyces cerevisiae under anaerobic conditions. We compare the metabolic fluxes and transcriptional regulation under aerobic and anaerobic conditions, with the objective of identifying the final electron acceptor...... reticulum are transferred to fumarate as the final electron acceptor. This model is supported by findings that the addition of fumarate under anaerobic (but not aerobic) conditions improves cell growth, specifically in the α-amylase-producing strain, in which it is not used as a carbon source. Our results...... provide a model for the molecular mechanism of anaerobic protein secretion using fumarate as the final electron acceptor, which may allow for further engineering of yeast for improved protein secretion under anaerobic growth conditions....

Kunstlik viljastamine - kas rahva püsimajäämise võti? / Michael Cook

Index Scriptorium Estoniae

Cook, Michael

2007-01-01

Kunstlikust viljastamisest pole üksi abi - vaid siis, kui noored mehed ja naised pööravad selja tarbimiskultusele ja individualismile, hakkab sündimus tõusma taastootmisest kõrgemale, kirjutab BioEdge toimetaja Michael Cook

An Efficient, "Burn in" Free Organic Solar Cell Employing a Nonfullerene Electron Acceptor.

Science.gov (United States)

Cha, Hyojung; Wu, Jiaying; Wadsworth, Andrew; Nagitta, Jade; Limbu, Saurav; Pont, Sebastian; Li, Zhe; Searle, Justin; Wyatt, Mark F; Baran, Derya; Kim, Ji-Seon; McCulloch, Iain; Durrant, James R

2017-09-01

A comparison of the efficiency, stability, and photophysics of organic solar cells employing poly[(5,6-difluoro-2,1,3-benzothiadiazol-4,7-diyl)-alt-(3,3'″-di(2-octyldodecyl)-2,2';5',2″;5″,2'″-quaterthiophen-5,5'″-diyl)] (PffBT4T-2OD) as a donor polymer blended with either the nonfullerene acceptor EH-IDTBR or the fullerene derivative, [6,6]-phenyl C 71 butyric acid methyl ester (PC 71 BM) as electron acceptors is reported. Inverted PffBT4T-2OD:EH-IDTBR blend solar cell fabricated without any processing additive achieves power conversion efficiencies (PCEs) of 9.5 ± 0.2%. The devices exhibit a high open circuit voltage of 1.08 ± 0.01 V, attributed to the high lowest unoccupied molecular orbital (LUMO) level of EH-IDTBR. Photoluminescence quenching and transient absorption data are employed to elucidate the ultrafast kinetics and efficiencies of charge separation in both blends, with PffBT4T-2OD exciton diffusion kinetics within polymer domains, and geminate recombination losses following exciton separation being identified as key factors determining the efficiency of photocurrent generation. Remarkably, while encapsulated PffBT4T-2OD:PC 71 BM solar cells show significant efficiency loss under simulated solar irradiation ("burn in" degradation) due to the trap-assisted recombination through increased photoinduced trap states, PffBT4T-2OD:EH-IDTBR solar cell shows negligible burn in efficiency loss. Furthermore, PffBT4T-2OD:EH-IDTBR solar cells are found to be substantially more stable under 85 °C thermal stress than PffBT4T-2OD:PC 71 BM devices. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Eesti disain on kõva, ent see tuleb moondada ekspordiks / Michael Thomson ; interv. Urmas Oja

Index Scriptorium Estoniae

Thomson, Michael

2008-01-01

Euroopa Disainiassotsiatsioonide Liidu presidendi ja Tallinnas toimunud festivali Disainiöö Eesti disainiauhinna Bruno žürii juhi Michael Thomsoni arvamus eesti disainist ning disainipoliitika vajalikkusest Eestis. Auhinnasaajate nimekiri

Influence of substitution of the proton donor and proton acceptor abilities of molecules. 1. The development method of definition proton donor and proton acceptor abilities A-H containing molecules

International Nuclear Information System (INIS)

Nurulloev, M.; Narziev, B.N.; Islomov, Z.; Fayzieva, M.

2005-01-01

The influence of nature of the assistant is investigated in work, it is quantity and a site on proton donor and proton acceptor abilities. A-H containing organic connections and ways, of definition of these abilities are developed by the method, of IR spectroscopy. It is developed model and it offered a technique of definition of these abilities. It is shown that the proton donor and proton acceptor is abilities of molecules as constants, are one of individual physical and chemical characteristics A-H of containing organic connections. These sizes determine the abilities of molecules, to form the intermolecular hydrogen connections, disabilities of the H-complexes formed in condensed, environments concerning to the non replaced molecule

Compassionate leadership? Some reflections on the work and life of Michael Lapsley

Directory of Open Access Journals (Sweden)

Ian A. Nell

2016-03-01

Full Text Available In June 2007, I had the privilege of attending a Healing of Memories workshop lead by Father Michael Lapsley, one of the founder members of the Institute for Healing of Memories. The purpose of the workshop was to help the predominantly white members of a middle class Dutch Reformed congregation in the Northern Suburbs of Cape Town and the predominantly coloured members of a congregation of the Evangelical Lutheran Church in Elsies River on the Cape Flats, to share their stories of the past with regard to apartheid with each other. Apart from the stories that were told and the sharing of experiences about the apartheid history that took place, I was struck by the way in which Father Lapsley conducted the workshop. There was a deep compassion for all the participants as was embodied through the way in which he treated each of us with respect. But apart from his cordiality in leading the workshop, one could sense a deeper source of compassion, a source revealing a compassionate understanding of God�s presence amidst the violence and turmoil in our broken world. The aim of this article is to reflect on whether one could speak of something like �compassionate leadership�, and to take a closer look at the relationship between compassion and God images in the life and work of Michael Lapsley. Special attention will be given to the way in which he exercises leadership through his many involvements related to his own personal story of trauma.Intradisciplinary and/or interdisciplinary implications: This article presents literary research on the notion of compassionate leadership as a specific kind of leadership. The results indicate that the leadership of Father Michael Lapsley does indeed portray features of this kind of leadership. The research can become the source for finding new strategies for religious leadership.

Quantum computing with acceptor spins in silicon.

Science.gov (United States)

Salfi, Joe; Tong, Mengyang; Rogge, Sven; Culcer, Dimitrie

2016-06-17

The states of a boron acceptor near a Si/SiO2 interface, which bind two low-energy Kramers pairs, have exceptional properties for encoding quantum information and, with the aid of strain, both heavy hole and light hole-based spin qubits can be designed. Whereas a light-hole spin qubit was introduced recently (arXiv:1508.04259), here we present analytical and numerical results proving that a heavy-hole spin qubit can be reliably initialised, rotated and entangled by electrical means alone. This is due to strong Rashba-like spin-orbit interaction terms enabled by the interface inversion asymmetry. Single qubit rotations rely on electric-dipole spin resonance (EDSR), which is strongly enhanced by interface-induced spin-orbit terms. Entanglement can be accomplished by Coulomb exchange, coupling to a resonator, or spin-orbit induced dipole-dipole interactions. By analysing the qubit sensitivity to charge noise, we demonstrate that interface-induced spin-orbit terms are responsible for sweet spots in the dephasing time [Formula: see text] as a function of the top gate electric field, which are close to maxima in the EDSR strength, where the EDSR gate has high fidelity. We show that both qubits can be described using the same starting Hamiltonian, and by comparing their properties we show that the complex interplay of bulk and interface-induced spin-orbit terms allows a high degree of electrical control and makes acceptors potential candidates for scalable quantum computation in Si.

Postharvest Processing and Benefits of Black Pepper, Coriander, Cinnamon, Fenugreek, and Turmeric Spices.

Science.gov (United States)

Balasubramanian, S; Roselin, P; Singh, K K; Zachariah, John; Saxena, S N

2016-07-26

Spices are prime source for flavor, aroma, and taste in cuisines and play an active role as medicines due to their high antioxidant properties. As medicine or food, the importance of spices cannot be overemphasized. The medicinal values of spices are very well established in treating various ailments like cancer, fever, malaria, stomach offset, nausea, and many more. A spice may be available in several forms: fresh, whole dried, or pre-ground dried which requires further processing to be utilized in the form of value-added product. This review paper deals with the cultivation, postharvesting, chemical composition, uses, health, and medicinal benefits of the selected spice viz., black pepper, coriander, cinnamon, fenugreek, turmeric, and technological advances in processing of spices viz., super critical fluid extraction, cryogenic grinding, and microencapsulation etc. This paper also focuses on issues related to utilization of spices toward its high end-product development and characterization in pharmaceuticals and other medicinal purposes. The availability of different spices and their varietal differences and location have their pertinent characters, which are much demanding to refine postharvest and processing to assure its quality in the international market.

Symmetry-Breaking Charge Transfer in a Zinc Chlorodipyrrin Acceptor for High Open Circuit Voltage Organic Photovoltaics

KAUST Repository

Bartynski, Andrew N.

2015-04-29

© 2015 American Chemical Society. Low open-circuit voltages significantly limit the power conversion efficiency of organic photovoltaic devices. Typical strategies to enhance the open-circuit voltage involve tuning the HOMO and LUMO positions of the donor (D) and acceptor (A), respectively, to increase the interfacial energy gap or to tailor the donor or acceptor structure at the D/A interface. Here, we present an alternative approach to improve the open-circuit voltage through the use of a zinc chlorodipyrrin, ZCl [bis(dodecachloro-5-mesityldipyrrinato)zinc], as an acceptor, which undergoes symmetry-breaking charge transfer (CT) at the donor/acceptor interface. DBP/ZCl cells exhibit open-circuit voltages of 1.33 V compared to 0.88 V for analogous tetraphenyldibenzoperyflanthrene (DBP)/C60-based devices. Charge transfer state energies measured by Fourier-transform photocurrent spectroscopy and electroluminescence show that C60 forms a CT state of 1.45 ± 0.05 eV in a DBP/C60-based organic photovoltaic device, while ZCl as acceptor gives a CT state energy of 1.70 ± 0.05 eV in the corresponding device structure. In the ZCl device this results in an energetic loss between ECT and qVOC of 0.37 eV, substantially less than the 0.6 eV typically observed for organic systems and equal to the recombination losses seen in high-efficiency Si and GaAs devices. The substantial increase in open-circuit voltage and reduction in recombination losses for devices utilizing ZCl demonstrate the great promise of symmetry-breaking charge transfer in organic photovoltaic devices.

Interviews with Michael Baxandall, February 3rd and 4th, 1994, Berkeley, CA

Directory of Open Access Journals (Sweden)

Allan Langdale

2009-12-01

Full Text Available The following interviews with Michael Baxandall were conducted in Berkeley on February 3rd and 4th of 1994. The content of these interviews include general responses about developments in art history in the years between 1960 and 1985, a period of dramatic modifications in the discipline. Among the issues are the rise of the social history of art and the sources from anthropology that informed Baxandall’s concept of the ‘Period Eye’. Baxandall talks about his own work, his personal intellectual history, and the scholars of past and current generations who influenced him. Other topics include Baxandall’s professional trajectory, the Warburg Library, and aspects of cultural history having to do with Renaissance Humanism. These interviews first appeared as an appendix to the PhD dissertation by Allan Langdale, Art History and Intellectual History: Michael Baxandall’s Work between 1963 and 1985, U. C. Santa Barbara, 1995.

Molecular designing of novel ternary copolymers of donor-acceptor polymers using genetic algorithm

International Nuclear Information System (INIS)

Arora, Vinita; Bakhshi, A.K.

2010-01-01

Graphical abstract: Alternate arrangement of donor acceptor moieties in the carbon backbone chain of an organic conjugated polymer is capable of inducing charge transfer and affects the electronic properties of the copolymer. Genetic algorithm along with simple NFC (negative factor counting) and IIM (inverse iteration method) has been used to optimize the properties of novel ternary copolymers based on polypyrrole PPy, polythiophene PTh and polyfuran PFu (as donor moieties) and containing >C=O and >C=CF 2 bridging units as acceptor moieties. - Abstract: An efficient designing route to novel ternary copolymers consisting of polypyrrole (PPy), polythiophene (PTh) and polyfuran (PFu) is developed with the help of genetic algorithm. Using the band structure results obtained from ab initio crystal orbital (CO) calculations, the electronic structures and conduction properties of real ternary copolymers based on donor acceptor type polymers are investigated. The electron rich heterocyclic rings in the backbone chain of the copolymer are joined together by electron withdrawing groups Y, carbonyl group (>C=O) and difluoromethylene group (>C=CF 2 ) in an attempt to design the conducting polymer with lowest band gap. A comparative study of various electronic properties is presented. The effects of substitution on the behaviour and properties of the copolymers as well as on the density of states (DOS) are discussed. Band gap decreases as a result of substitution on the polymer backbone chain due to decrease in ionization potential and increase in electron affinity values. This is expected to enhance the intrinsic conductivity of the resulting copolymer. Use of alternate donor acceptor moieties within the repeat units should maximize the extended π conjugation.

Molecular designing of novel ternary copolymers of donor-acceptor polymers using genetic algorithm

Energy Technology Data Exchange (ETDEWEB)

Arora, Vinita [Department of Chemistry, University of Delhi, Delhi 110 007 (India); Bakhshi, A.K., E-mail: akbakhshi2000@yahoo.com [Department of Chemistry, University of Delhi, Delhi 110 007 (India)

2010-08-03

Graphical abstract: Alternate arrangement of donor acceptor moieties in the carbon backbone chain of an organic conjugated polymer is capable of inducing charge transfer and affects the electronic properties of the copolymer. Genetic algorithm along with simple NFC (negative factor counting) and IIM (inverse iteration method) has been used to optimize the properties of novel ternary copolymers based on polypyrrole PPy, polythiophene PTh and polyfuran PFu (as donor moieties) and containing >C=O and >C=CF{sub 2} bridging units as acceptor moieties. - Abstract: An efficient designing route to novel ternary copolymers consisting of polypyrrole (PPy), polythiophene (PTh) and polyfuran (PFu) is developed with the help of genetic algorithm. Using the band structure results obtained from ab initio crystal orbital (CO) calculations, the electronic structures and conduction properties of real ternary copolymers based on donor acceptor type polymers are investigated. The electron rich heterocyclic rings in the backbone chain of the copolymer are joined together by electron withdrawing groups Y, carbonyl group (>C=O) and difluoromethylene group (>C=CF{sub 2}) in an attempt to design the conducting polymer with lowest band gap. A comparative study of various electronic properties is presented. The effects of substitution on the behaviour and properties of the copolymers as well as on the density of states (DOS) are discussed. Band gap decreases as a result of substitution on the polymer backbone chain due to decrease in ionization potential and increase in electron affinity values. This is expected to enhance the intrinsic conductivity of the resulting copolymer. Use of alternate donor acceptor moieties within the repeat units should maximize the extended {pi} conjugation.

Comparative evaluation of the acceptor properties of quinone derivatized polypyridinic ligands

Energy Technology Data Exchange (ETDEWEB)

Norambuena, Ester [Departamento de Quimica, Facultad de Ciencias Basicas, Universidad Metropolitana de Ciencias de la Educacion, Santiago (Chile); Olea-Azar, Claudio [Facultad de Ciencias Quimicas y Farmaceuticas, Universidad de Chile, Santiago (Chile); Delgadillo, Alvaro [Departamento de Quimica, Facultad de Ciencias, Universidad de La Serena, Casilla 599, La Serena (Chile); Barrera, Mauricio [Facultad de Quimica, Pontificia Universidad Catolica de Chile, Casilla 306, Santiago (Chile); Loeb, Barbara, E-mail: bloeb@puc.cl [Facultad de Quimica, Pontificia Universidad Catolica de Chile, Casilla 306, Santiago (Chile)

2009-05-18

The reduction properties of four acceptor polipyridyl ligands modified with quinones were studied by different experimental methods, as cyclic voltammetry and ESR spectroscopy, and by theoretical calculations. ESR spectra for the reduced ligands show different patterns among them, suggesting that the quinone moiety plays an important role in the delocalization of the received electron. The hyperfine coupling constants calculated for the magnetic nucleus were in good agreement with experimental data. The results were additionally interpreted with the help of two theoretical predictors: the electrophilicity index and the Fukui function obtained through the spin density. The results suggest that 12,17-dihydronaphtho-[2,3-h]dipyrido[3,2-a:2',3'-c]-phenazine-12,17-dione, Aqphen, shows the most promising behavior to be employed as an acceptor ligand in complexes with potential application in NLO devices.

Comparative evaluation of the acceptor properties of quinone derivatized polypyridinic ligands

International Nuclear Information System (INIS)

Norambuena, Ester; Olea-Azar, Claudio; Delgadillo, Alvaro; Barrera, Mauricio; Loeb, Barbara

2009-01-01

The reduction properties of four acceptor polipyridyl ligands modified with quinones were studied by different experimental methods, as cyclic voltammetry and ESR spectroscopy, and by theoretical calculations. ESR spectra for the reduced ligands show different patterns among them, suggesting that the quinone moiety plays an important role in the delocalization of the received electron. The hyperfine coupling constants calculated for the magnetic nucleus were in good agreement with experimental data. The results were additionally interpreted with the help of two theoretical predictors: the electrophilicity index and the Fukui function obtained through the spin density. The results suggest that 12,17-dihydronaphtho-[2,3-h]dipyrido[3,2-a:2',3'-c]-phenazine-12,17-dione, Aqphen, shows the most promising behavior to be employed as an acceptor ligand in complexes with potential application in NLO devices.

An effective Hamiltonian approach for Donor-Bridge-Acceptor electronic transitions: Exploring the role of bath memory

Directory of Open Access Journals (Sweden)

E.R. Bittner

2016-03-01

Full Text Available We present here a formally exact model for electronic transitions between an initial (donor and final (acceptor states linked by an intermediate (bridge state. Our model incorporates a common set of vibrational modes that are coupled to the donor, bridge, and acceptor states and serves as a dissipative bath that destroys quantum coherence between the donor and acceptor. Taking the memory time of the bath as a free parameter, we calculate transition rates for a heuristic 3-state/2 mode Hamiltonian system parameterized to represent the energetics and couplings in a typical organic photovoltaic system. Our results indicate that if the memory time of the bath is of the order of 10-100 fs, a two-state kinetic (i.e., incoherent hopping model will grossly underestimate overall transition rate.

Photochemical stability of conjugated polymers, electron acceptors and blends for polymer solar cells resolved in terms of film thickness and absorbance

DEFF Research Database (Denmark)

Tromholt, Thomas; Vesterager Madsen, Morten; Carlé, Jon Eggert

2012-01-01

Photochemical degradation at 1 sun under AM1.5G illumination was performed on six conjugated polymers and five different electron acceptors. Additionally, the respective polymer:PC60BM and P3HT:electron acceptor blends were studied, and all degradations were resolved in terms of film thickness...... within each material group were found to vary for both the pure polymers and the blends. The stability ranking between the materials of the pure polymers was found to be similar to the ranking for their respective blends, implying that the photochemical stability of a pure polymer is a good measure...... of its associated blend stability. Different electron acceptors were found to stabilize P3HT decreasingly with decreasing donor–acceptor LUMO–LUMO gap. Destabilization of P3HT was observed in the case of the electron acceptor ICBA. Additionally, the decreased stabilization of P3HT by high LUMO electron...

Michael Maier--nine newly discovered letters.

Science.gov (United States)

Lenke, Nils; Roudet, Nicolas; Tilton, Hereward

2014-02-01

The authors provide a transcription, translation, and evaluation of nine newly discovered letters from the alchemist Michael Maier (1568-1622) to Gebhardt Johann von Alvensleben (1576-1631), a noble landholder in the vicinity of Magdeburg. Stemming from the final year of his life, this correspondence casts new light on Maier's biography, detailing his efforts to secure patronage amid the financial crisis of the early Thirty Years' War. While his ill-fated quest to perfect potable gold continued to form the central focus of his patronage suits, Maier also offered his services in several arts that he had condemned in his printed works, namely astrology and "supernatural" magic. Remarks concerning his previously unknown acquaintance with Heinrich Khunrath call for a re-evaluation of Maier's negotiation of the discursive boundaries between Lutheran orthodoxy and Paracelsianism. The letters also reveal Maier's substantial contribution to a work previously ascribed solely to the English alchemist Francis Anthony.

Political Cinema and Culture industry: the work of Michael Moore

OpenAIRE

Cristiane Toledo Maria

2015-01-01

This article aims to reflect upon the production of the American filmmaker Michael Moore, proposing as a central question the relationship established between art and politics in a historical moment which, on one side, points to the crisis of capitalism and, on the other side, to the political fragmentation of the working class. Focusing on the analysis of the documentaries Roger & Me (1989) and Capitalism: a love story (2009), this article is an attempt to understand the method developed by ...

Estratégia competitiva: Michael Porter 30 anos depois

Directory of Open Access Journals (Sweden)

Manuel Portugal Ferreira

2009-12-01

Full Text Available Os estudos de estratégia têm sido muito influenciados pelos trabalhos de Michael Porter, em todas as suas fases, como as cinco forças, as estratégias genéricas, a cadeia de valor e as vantagens competitivas das nações. Neste artigo, analisou-se a influência de Porter nos trabalhos brasileiros em estratégia, a partir dos trabalhos selecionados e apresentados no EnANPAD. No levantamento para a análise dos artigos, considerando 10 anos de EnANPAD (1997-2006, foram selecionados 46 artigos. A identificação e seleção dos artigos envolveram os seguintes critérios: busca complementar por palavra-chave Porter na base de dados do EnANPAD; avaliação dos títulos e resumos dos artigos apresentados na área de estratégia entre 1997 e 2006, bem como na íntegra quando necessário. Procedeu-se também à análise das referências utilizadas nos artigos e o posicionamento dos autores em relação às tipologias de Porter. Como resultado, verificou-se que Michael Porter é um autor com grande influência nas pesquisas acadêmicas de estratégia. Seus estudos mais utilizados são os da análise da indústria e das estratégias genéricas, e também se verificou que a maioria dos estudos analisados é favorável aos seus conceitos, mesmo existindo pesquisas contrárias.

Mechanism and Dynamics of Charge Transfer in Donor-Bridge-Acceptor Systems

NARCIS (Netherlands)

Gorczak-Vos, N.

2016-01-01

Photoinduced charge transfer in organic materials is a fundamental process in various biological and technological areas. Donor-bridge-acceptor (DBA) molecules are used as model systems in numerous theoretical and experimental work to systematically study and unravel the underlying mechanisms of

Enantiopure vs. Racemic Naphthalimide End-Capped Helicenic Non-Fullerene Electron Acceptors: Impact on Organic Photovoltaics Performance

OpenAIRE

Josse , Pierre; Favereau , Ludovic; Shen , Chengshuo; Dabos-Seignon , Sylvie; Blanchard , Philippe; Cabanetos , Clement; Crassous , Jeanne

2017-01-01

International audience; Impact of the enantiopurity on organic photovoltaics (OPV) performance was investigated through the synthesis of racemic and enantiomerically pure naphthalimide end-capped helicenes and their application as non-fullerene molecular electron acceptors in OPV devices. A very strong increase of the device performance was observed by simply switching from the racemic to the enantiopure forms of these π-helical non-fullerene acceptors with power conversion efficiencies jumpi...

Neuroprotection by Spice-Derived Nutraceuticals: You Are What You Eat!

Science.gov (United States)

Kannappan, Ramaswamy; Gupta, Subash Chandra; Kim, Ji Hye; Reuter, Simone

2011-01-01

Numerous lines of evidence indicate that chronic inflammation plays a major role in the development of various neurodegenerative diseases, including Alzheimer’s disease, Parkinson’s disease, multiple sclerosis, brain tumor, and meningitis. Why these diseases are more common among people from some countries than others is not fully understood, but lifestyle factors have been linked to the development of neurodegenerative diseases. For example, the incidence of certain neurodegenerative diseases among people living in the Asian subcontinent, where people regularly consume spices, is much lower than in countries of the western world. Extensive research over the last 10 years has indicated that nutraceuticals derived from such spices as turmeric, red pepper, black pepper, licorice, clove, ginger, garlic, coriander, and cinnamon target inflammatory pathways, thereby may prevent neurodegenerative diseases. How these nutraceuticals modulate various pathways and how they exert neuroprotection are the focus of this review. PMID:21360003