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Sample records for prurigo nodularis pn

  1. Combination therapy of fexofenadine and montelukast is effective in prurigo nodularis and pemphigoid nodularis.

    Science.gov (United States)

    Shintani, Takako; Ohata, Chika; Koga, Hiroshi; Ohyama, Bungo; Hamada, Takahiro; Nakama, Takekuni; Furumura, Minao; Tsuruta, Daisuke; Ishii, Norito; Hashimoto, Takashi

    2014-01-01

    In this study, we report on the efficacy of combination therapy of second-generation antihistamine antagonist, fexofenadine hydrochloride, and leukotriene receptor inhibitor, montelukast sodium, for the treatment of 15 prurigo nodularis or pemphigoid nodularis patients, in whom conventional therapy was ineffective. All patients received 10 mg montelukast once a day and 240 mg fexofenadine twice a day for 4 weeks in addition to other medications they had been taking. We assessed the manifestations of the lesions and itching intensity before and after the therapy, and we evaluated each patient as (i) markedly improved, (ii) improved, (iii) slightly improved, (iv) no change, (v) worse. Two patients (13.3%) were evaluated as markedly improved, and the lesions of one patient completely disappeared. Three patients (20.0%) were evaluated as improved, and six patients (40.0%) as slightly improved. Thus, 11 of 15 cases (73.3%) improved by combination therapy of fexofenadine and montelukast, in which nine cases (75.0%) of prurigo nodularis and two cases (66.7%) of pemphigoid nodularis were involved. No patients revealed any side effects. This study revealed that combination therapy of fexofenadine and montelukast was effective for some patients with conventional therapy-resistant prurigo nodularis and pemphigoid nodularis. © 2013 Wiley Periodicals, Inc.

  2. Parthenium dermatitis manifesting clinically as polymorphic light eruption and prurigo nodularis- like lesions with vasculitis-like picture on histopathology

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    Chembolli Lakshmi

    2011-01-01

    Full Text Available Parthenium dermatitis is a widespread and distressing dermatoses in rural and urban India caused by the air borne allergen of the Compositae weed Parthenium hysterophorus. Parthenium dermatitis has been thought to be mediated solely by type IV hypersensitivity, but recently a combined immediate (type I and delayed (type IV hypersensitivity mechanism has been postulated in the initiation and perpetuation of parthenium dermatitis, especially in sensitized subjects with an atopic diathesis. Initially, the exposed sites of the body are involved. Later in the course of the disease, unexposed sites may get involved. Various clinical presentations have been described in parthenium dermatitis. Typically, it presents as an air borne contact dermatitis (ABCD involving the eyelids and nasolabial folds Other presentations include a photodermatitis (essentially a pseudo photodermatitis, atopic dermatitis, seborrheic dermatitis, exfoliative dermatitis, hand dermatitis. Photosensitive lichenoid dermatitis and prurigo nodularis are rarer presentations. Uncommon presentations have been described in parthenium dermatitis. They include prurigo nodularis-like lesions and photosensitive lichenoid eruption. Three cases are presented, two of whom presented as polymorphic-like lesions and one as prurigo nodularis. All three patch tested positive to parthenium on Day 2. Prick testing was positive in two of the three patients. Parthenium dermatitis mimicking polymorphic light eruption has not been reported. Histopathology revealed vasculitis in the lesional skin in two of the patients. Although leukocytoclastic vasculitis has been reported earlier from the prick-tested site, this is the first report demonstrating the presence of vasculitis in lesional skin of parthenium dermatitis.

  3. Oral ketotifen and topical antibiotic therapy in the management of pruritus in prurigo nodularis: A randomized, controlled, single-blind, parallel study

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    Ashimav Deb Sharma

    2013-01-01

    Full Text Available Aims: To evaluate the role of oral ketotifen and topical antibiotic therapy in the management of pruritus in prurigo nodularis (PN patients. Materials and Methods: Twenty-seven patients with PN and a history of atopy with raised IgE were included in this study in a dermatology clinic. All patients had positive growth of Staphylococcus aureus on the lesional skin swab. All patients received topical halobetasol and oral hydroxyzine for 4 weeks. In addition, all patients in the study group received oral ketotifen and topical antibiotic therapy for 4 weeks. Randomization was performed by using a table of random numbers, and the participants were randomly allocated to one of the two groups in the study. The study was a single-blind study, and the blinding was done by the investigator. Results: Of the 14 patients in the study group, 9 had complete relief from pruritus by the end of first week, which was maintained till the end of 4 weeks. In the control group, mild to moderate reduction in the intensity of pruritus in the PN lesions of all patients were noted by the end of the first week. No further improvement in the level of pruritus was noted in the participants during the trial period. The treatment was well tolerated by the patients, and the adverse reactions of drugs were minimal in both groups. Conclusions: This study showed that oral ketotifen and topical antibiotic therapy can be helpful in the management of pruritus in PN patients.

  4. Aktinsk prurigo

    DEFF Research Database (Denmark)

    Stockbridge, Eva Boné; Deleuran, Mette Søndergaard; Steiniche, Torben

    2008-01-01

    to the conclusion that the patient suffered from Actinic Prurigo. The disease was very severe and there was a lack of response to treatment with oral prednisolone, antihistamines and pentoxyfyllin. Therefore the patient was treated with Thalidomide 50 mg/25 mg daily (alternating). This resulted in the complete...

  5. HLA typing in actinic prurigo.

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    Sheridan, D P; Lane, P R; Irvine, J; Martel, M J; Hogan, D J

    1990-06-01

    Thirty-two actinic prurigo patients of Cree ancestry underwent human lymphocyte antigen (HLA) typing and were compared with 32 control subjects of Cree ancestry. We found a significantly increased frequency of HLA-A24 and Cw4 antigens and a significant decrease in the frequency of the A3 antigen in actinic prurigo patients. These HLA associations may be helpful in determining whether actinic prurigo is a distinct disease or a variant of polymorphous light eruption.

  6. Prurigo pigmentosa: An underdiagnosed disease?

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    Boer A

    2006-01-01

    Full Text Available Prurigo pigmentosa is a distinctive inflammatory disease first described by the Japanese dermatologist Masaji Nagashima in 1971. It is typified by recurrent, pruritic erythematous macules, papules and papulovesicles that resolve leaving behind netlike pigmentation. The disease is rarely diagnosed outside Japan, because clinicians outside Japan are not well conversant with the criteria for its diagnosis. Only one patient from India has been published previously under the diagnosis of prurigo pigmentosa, a hint that the disease may be under-recognized in India. We present an account of our observations in patients diagnosed with prurigo pigmentosa who were of five different nationalities, namely, Japanese, German, Indonesian, Turkish and Iranian. With this article we seek to increase awareness for the condition among dermatologists in India and we provide criteria for its diagnosis, both clinically and histopathologically.

  7. [Some clinical symptoms and allergens on asthma-prurigo syndrome].

    Science.gov (United States)

    Rudzki, E; Romański, B; Dynowska, D; Kaczmarski, M; Olendzka-Rzepecka, E; Kurzawa, R; Obtułowicz, K; Blinowski, J; Korzeniowska-Zuk, E; Piela, Z; Szmurło, A; Stroiński, J; Doniec, Z; Pulka, G

    1998-01-01

    The group of 146 patients suffering from asthma-prurigo syndrome (85 adults and 64 children) have been inquired in many various clinical centers. It was established that in 79.6% of the patients the first symptoms of illness appeared already in infancy and only 28.2% of the patients had negative familiar anamnesis on the allergy. In 73.2% of the patients with asthma-prurigo syndrome the symptoms of atopic dermatitis persisted longer than asthma symptoms and in 89.9% of them asthma-prurigo symptoms accompanied other form of allergic diseases. The most important causal allergens provoking asthma-prurigo symptoms were: house dust (in 64.4% of the patients), chocolate (in 42.2%), cat epithelia (in 40.2%) and cow milk proteins (in 29.5% of the patients).

  8. European academy of dermatology and venereology European prurigo project: expert consensus on the definition, classification and terminology of chronic prurigo.

    Science.gov (United States)

    Pereira, M P; Steinke, S; Zeidler, C; Forner, C; Riepe, C; Augustin, M; Bobko, S; Dalgard, F; Elberling, J; Garcovich, S; Gieler, U; Gonçalo, M; Halvorsen, J A; Leslie, T A; Metz, M; Reich, A; Şavk, E; Schneider, G; Serra-Baldrich, E; Ständer, H F; Streit, M; Wallengren, J; Weller, K; Wollenberg, A; Bruland, P; Soto-Rey, I; Storck, M; Dugas, M; Weisshaar, E; Szepietowski, J C; Legat, F J; Ständer, S

    2017-08-31

    The term prurigo has been used for many decades in dermatology without clear definition, and currently used terminology of prurigo is inconsistent and confusing. Especially, itch-related prurigo remains unexplored regarding the epidemiology, clinical profile, natural course, underlying causes, available treatments and economic burden, although burdensome and difficult to treat. To address these issues, the multicentre European Prurigo Project (EPP) was designed to increase knowledge on chronic prurigo (CPG). In the first step, European experts of the EADV Task Force Pruritus (TFP) aimed to achieve a consensus on the definition, classification and terminology of CPG. Additionally, procedures of the cross-sectional EPP were discussed and agreed upon. Discussions and surveys between members of the TFP served as basis for a consensus conference. Using the Delphi method, consensus was defined as an agreement ≥75% among the present members. Twenty-four members of the TFP participated in the consensus conference. Experts consented that CPG should be used as an umbrella term for the range of clinical manifestations (e.g. papular, nodular, plaque or umbilicated types). CPG is considered a distinct disease defined by the presence of chronic pruritus for ≥6 weeks, history and/or signs of repeated scratching and multiple localized/generalized pruriginous skin lesions (whitish or pink papules, nodules and/or plaques). CPG occurs due to a neuronal sensitization to itch and the development of an itch-scratch cycle. This new definition and terminology of CPG should be implemented in dermatology to harmonize communication in the clinical routine, clinical trials and scientific literature. Acute/subacute forms of prurigo are separated entities, which need to be differentiated from CPG and will be discussed in a next step. In the near future, the cross-sectional EPP will provide relevant clinical data on various aspects of CPG leading to new directions in the scientific

  9. Personal Network (PN) Applications

    DEFF Research Database (Denmark)

    Prasad, Ramjee; Skouby, K.

    2005-01-01

    The applications of PN will be realised under many scenarios where users can have access to their personal network all the time. This network will enable the user to share critical information, play games, control their home remotely, etc. All this will be achieved with seamless interworking...... and handover between networks and user devices. This paper presents an array of use case scenarios that validates the ubiquitous usage of PN....

  10. Personal network (PN) applications

    DEFF Research Database (Denmark)

    Prasad, R.; Skouby, Knud Erik

    2005-01-01

    The applications of PN will be realised under many scenarios where users can have access to their personal network all the time. This network will enable the user to share critical information, play games, control their home remotely, etc. All this will be achieved with seamless interworking...... and handover between networks and user devices. This paper presents an array of use case scenarios that validates the ubiquitous usage of PN....

  11. Alopecia Areata With Folliculitis Decalvans

    Directory of Open Access Journals (Sweden)

    Kumar Kailash

    1997-01-01

    Full Text Available Cutaneous horns are rare horny excrescences which occur in various dermatoses. We report a girl with prurigo nodularis who developed a horn on one of the nodules. This unique association has not been reported so far.

  12. Elastosonography in the diagnosis of the nodular breast lesions: preliminary report; Elastosonografia nella caratterizzazione delle lesioni nodulari della mammella: esperienza preliminare

    Energy Technology Data Exchange (ETDEWEB)

    Giuseppetti, Gian Marco; Di Cioccio, Barbara; Baldassarre, Silvia [Univ. Politecnica delle Marche, Ancona (Italy). Istituto di radiologia; Martegani, Alberto [Ospedale Valduce, Como (Italy). Servizio di radiologia

    2005-07-15

    Purpose. To assess the diagnostic accuracy of elastography in characterising nodular breast lesions. Materials and methods. A total of 82 patients who received mammographic, ultrasonographic and elastographic evaluation in a single session at two Italian centres (Dept of Radiology, Az. Ospedali Riuniti, Ancona, and Ospedale Valduce, Corno, Italy) between January and August 2004 according to identical protocols exhibited 91 nodules that were subjected to cytological/histological examination. Lesions were classified and scored and the sensitivity of elastography calculated. Results. Overall sensitivity and specificity were 79% and 89%, respectively. However, sensitivity was 86% and 65% and specificity 100% and 62% for lesions < 2 cm and > 2 cm in diameter, respectively. Despite the small sample and the fact that it does not include the full range of cell types, tumour cell composition seemed to affect accuracy. Conclusions. Elastography is easy and rapid to perform. Larger studies are needed to establish semiological patterns; despite the small patient sample, these data provide an interesting contribution. [Italian] Scopo. Valutare l'accuratezza diagnostica dell'elastosonografia nella caratterizzazione delle lesioni nodulari della mammella. Materiale e metodi. Il campione e costituito da 91 lesioni, tutte verificate, osservate in due centri nel periodo gennaio/agosto 2004. Tutte le pazienti sono state sottoposte nella stessa seduta a mammografia, ecografia ed elastosonografia secondo protocolli comuni ai due centri. I risultati sono stati classificati e valutati secondo uno score predefinito in base al quale sono state calcolate specificita e sensibilita. Risultati. In accordo con i criteri classificativi l'esame ha evidenziato, globalmente, una sensibilita del 79% ed una specificita del 89% con diverso comportamento in rapporto alle dimensioni. In particolare per diametri inferiori a cm 2 si e osservata una sensibilita del 86% con specificita del 100

  13. Atomically Abrupt Topological p-n Junction.

    Science.gov (United States)

    Kim, Sung Hwan; Jin, Kyung-Hwan; Kho, Byung Woo; Park, Byeong-Gyu; Liu, Feng; Kim, Jun Sung; Yeom, Han Woong

    2017-08-24

    Topological insulators (TI's) are a new class of quantum matter with extraordinary surface electronic states, which bear great potential for spintronics and error-tolerant quantum computing. In order to put a TI into any practical use, these materials need to be fabricated into devices whose basic units are often p-n junctions. Interesting electronic properties of a 'topological' p-n junction were proposed theoretically such as the junction electronic state and the spin rectification. However, the fabrication of a lateral topological p-n junction has been challenging because of materials, process, and fundamental reasons. Here, we demonstrate an innovative approach to realize a p-n junction of topological surface states (TSS's) of a three-dimensional (3D) topological insulator (TI) with an atomically abrupt interface. When a ultrathin Sb film is grown on a 3D TI of Bi2Se3 with a typical n-type TSS, the surface develops a strongly p-type TSS through the substantial hybridization between the 2D Sb film and the Bi2Se3 surface. Thus, the Bi2Se3 surface covered partially with Sb films bifurcates into areas of n- and p-type TSS's as separated by atomic step edges with a lateral electronic junction of as short as 2 nm. This approach opens a different avenue toward various electronic and spintronic devices based on well-defined topological p-n junctions with the scalability down to atomic dimensions.

  14. Molecular detection and genetic identification of Borrelia garinii and Borrelia afzelii from patients presenting with a rare skin manifestation of prurigo pigmentosa in Taiwan.

    Science.gov (United States)

    Chao, Li-Lian; Lu, Chin-Fang; Shih, Chien-Ming

    2013-12-01

    To determine the genetic identity of Borrelia spirochetes isolated from patients with an unusual skin lesion of prurigo pigmentosa (PP) in Taiwan. The causative agents responsible for human borreliosis were clarified. Serum samples and skin specimens were collected from 14 patients with suspected PP and five controls. Serological testing by Western immunoblot analysis and isolation of Borrelia spirochetes from skin specimens were used to verify the Borrelia infection. Genetic identities of isolated spirochetes were determined by analyzing the gene sequences amplified by PCR assay based on the 5S (rrf)-23S (rrl) intergenic spacer amplicon gene of Borrelia burgdorferi sensu lato. Borrelia spirochetes were isolated from skin biopsies of three patients. Serological evidence of Borrelia infection in these patients was also confirmed by elevated IgG and IgM antibodies against the major protein antigens of B. burgdorferi. Phylogenetic analysis revealed that these detected spirochetes are genetically affiliated to the genospecies of Borrelia garinii and Borrelia afzelii with high sequence homology within the genospecies of B. garinii (91.0-98.7%) and B. afzelii (97%). This study provides the first evidence of B. garinii and B. afzelii isolated and identified in patients with PP. Whether this unusual skin lesion is a new manifestation of Lyme disease needs to be studied further. Copyright © 2013 International Society for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

  15. Cimidíase (dermatose por percevejo: uma causa de prurigo a ser lembrada Bedbugs (Heteroptera, Cimicidae: an etiology of pruritus to be remembered

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    Paulo Ricardo Criado

    2011-02-01

    Full Text Available Descrevemos uma doente de 19 anos que nos procurou com quadro de intenso prurido há 2 semanas e demonstrando lesões eritêmato-pápulo-urticadas mais intensamente distribuídas nos membros superiores e inferiores. A anamnese detalhada excluiu causas internas e medicamentos como uma possível causa do prurigo. Após orientações quanto a dedetização do domicílio a doente retornou no consultório após 3 semanas sem lesões cutâneas e trazendo em um pote de vidro vários percevejos coletados após a dedetização.This report describes a 19-year old female patient, who sought medical attention for severe itching of two weeks' duration. Erythematous papules and wheals were found, principally on her upper and lower limbs. Careful anamnesis excluded other etiologies of the pruritus, including those related to internal diseases and medication. Following counseling regarding the need to contract a domestic pest control company, the patient returned to the clinic three weeks later with no skin lesions and bearing a glass jar containing several bedbugs collected following pest control treatment.

  16. Esophageal Cancer: Associations With (pN+) Lymph Node Metastases.

    Science.gov (United States)

    Rice, Thomas W; Ishwaran, Hemant; Hofstetter, Wayne L; Schipper, Paul H; Kesler, Kenneth A; Law, Simon; Lerut, E M R; Denlinger, Chadrick E; Salo, Jarmo A; Scott, Walter J; Watson, Thomas J; Allen, Mark S; Chen, Long-Qi; Rusch, Valerie W; Cerfolio, Robert J; Luketich, James D; Duranceau, Andre; Darling, Gail E; Pera, Manuel; Apperson-Hansen, Carolyn; Blackstone, Eugene H

    2017-01-01

    To identify the associations of lymph node metastases (pN+), number of positive nodes, and pN subclassification with cancer, treatment, patient, geographic, and institutional variables, and to recommend extent of lymphadenectomy needed to accurately detect pN+ for esophageal cancer. Limited data and traditional analytic techniques have precluded identifying intricate associations of pN+ with other cancer, treatment, and patient characteristics. Data on 5806 esophagectomy patients from the Worldwide Esophageal Cancer Collaboration were analyzed by Random Forest machine learning techniques. pN+, number of positive nodes, and pN subclassification were associated with increasing depth of cancer invasion (pT), increasing cancer length, decreasing cancer differentiation (G), and more regional lymph nodes resected. Lymphadenectomy necessary to accurately detect pN+ is 60 for shorter, well-differentiated cancers (<2.5 cm) and 20 for longer, poorly differentiated ones. In esophageal cancer, pN+, increasing number of positive nodes, and increasing pN classification are associated with deeper invading, longer, and poorly differentiated cancers. Consequently, if the goal of lymphadenectomy is to accurately define pN+ status of such cancers, few nodes need to be removed. Conversely, superficial, shorter, and well-differentiated cancers require a more extensive lymphadenectomy to accurately define pN+ status.

  17. Agent-based Personal Network (PN) service architecture

    DEFF Research Database (Denmark)

    Jiang, Bo; Olesen, Henning

    2004-01-01

    In this paper we proposte a new concept for a centralized agent system as the solution for the PN service architecture, which aims to efficiently control and manage the PN resources and enable the PN based services to run seamlessly over different networks and devices. The working principle......, control procedure and enabling techniques behind the agent based solution are the main focuses of this paper....

  18. Mapping Pn amplitude spreading and attenuation in Asia

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Xiaoning [Los Alamos National Laboratory; Phillips, William S [Los Alamos National Laboratory; Stead, Richard J [Los Alamos National Laboratory

    2010-12-06

    Pn travels most of its path in the mantle lid. Mapping the lateral variation of Pn amplitude attenuation sheds light on material properties and dynamics of the uppermost region of the mantle. Pn amplitude variation depends on the wavefront geometric spreading as well as material attenuation. We investigated Pn geometric spreading, which is much more complex than a traditionally assumed power-law spreading model, using both synthetic and observed amplitude data collected in Asia. We derived a new Pn spreading model based on the formulation that was proposed previously to account for the spherical shape of the Earth (Yang et. al., BSSA, 2007). New parameters derived for the spreading model provide much better correction for Pn amplitudes in terms of residual behavior. Because we used observed Pn amplitudes to construct the model, the model incorporates not only the effect of the Earth's spherical shape, but also the effect of potential upper-mantle velocity gradients in the region. Using the new spreading model, we corrected Pn amplitudes measured at 1, 2, 4 and 6 Hz and conducted attenuation tomography. The resulting Pn attenuation model correlates well with the regional geology. We see high attenuation in regions such as northern Tibetan Plateau and the western Pacific subduction zone, and low attenuation for stable blocks such as Sichuan and Tarim basins.

  19. Novel pneumoviruses (PnVs): Evolution and inflammatory pathology

    Energy Technology Data Exchange (ETDEWEB)

    Glineur, Stephanie F. [Inflammation Immunobiology Section, Laboratory of Allergic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892-1883 (United States); Renshaw, Randall W. [Animal Health Diagnostic Center, College of Veterinary Medicine, Cornell University, PO Box 5786, Ithaca, New York, NY 14851-5786 (United States); Percopo, Caroline M.; Dyer, Kimberly D. [Inflammation Immunobiology Section, Laboratory of Allergic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892-1883 (United States); Dubovi, Edward J. [Animal Health Diagnostic Center, College of Veterinary Medicine, Cornell University, PO Box 5786, Ithaca, New York, NY 14851-5786 (United States); Domachowske, Joseph B. [Department of Pediatrics, SUNY Upstate Medical University, Syracuse, NY 13210 (United States); Rosenberg, Helene F., E-mail: hrosenberg@niaid.nih.gov [Inflammation Immunobiology Section, Laboratory of Allergic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892-1883 (United States)

    2013-09-01

    A previous report of a novel pneumovirus (PnV) isolated from the respiratory tract of a dog described its significant homology to the rodent pathogen, pneumonia virus of mice (PVM). The original PnV–Ane4 pathogen replicated in and could be re-isolated in infectious state from mouse lung but elicited minimal mortality compared to PVM strain J3666. Here we assess phylogeny and physiologic responses to 10 new PnV isolates. The G/glycoprotein sequences of all PnVs include elongated amino-termini when compared to the characterized PVMs, and suggest division into groups A and B. While we observed significant differences in cytokine production and neutrophil recruitment to the lungs of BALB/c mice in response to survival doses (50 TCID{sub 50} units) of representative group A (114378-10-29-KY-F) and group B (7968-11-OK) PnVs, we observed no evidence for positive selection (dN>dS) among the PnV/PnV, PVM/PnV or PVM/PVM G/glycoprotein or F/fusion protein sequence pairs. - Highlights: • We consider ten novel isolates of the pneumovirus (PnV) first described by Renshaw and colleagues. • The G/glycoprotein sequences of all PnVs include elongated amino-termini when compared to PVM. • We detect cytokine production and neutrophil recruitment to the lungs of mice in response to PnV. • We observed no evidence for positive selection (dN>dS) among the gene sequence pairs.

  20. 19th Scientific Readings Devoted to P.N. Chirvinskiy

    Directory of Open Access Journals (Sweden)

    I. Ya. Ilaltdinov

    2017-03-01

    Full Text Available Scientific conference devoted to P.N. Chirvinskiy was held in the Perm State University (January 2017. The problems of mineralogy, petrology, lithology, metallogeny and geochemistry were discussed.

  1. A 4PN-exact approximation to General Relativity

    CERN Document Server

    Brizuela, David

    2010-01-01

    An approximation to General Relativity is presented which agrees with the Einstein field equations up to and including the fourth post-Newtonian (PN) order. This approximation is formulated in a fully constrained scheme: all involved equations are explicitly elliptic except the wave equation that describes the two independent degrees of freedom of the gravitational field. The formalism covers naturally the conformal-flat-condition (CFC) approach by Isenberg, Wilson, and Mathews and the improved second PN-order exact approach CFC+. For stationary configurations, like Kerr black holes, agreement with General Relativity is achieved even through 5PN order. In addition, we analyze in detail a particularly interesting 2PN-exact waveless approximation which results from imposing more restrictive conditions. The proposed scheme can be considered as a further development on the waveless approach suggested by Schaefer and Gopakumar [Phys. Rev. D {\\bf 69}, 021501 (2004)].

  2. Novel Fractional Order Calculus Extended PN for Maneuvering Targets

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    Jikun Ye

    2017-01-01

    Full Text Available Based on the theory of fractional order calculus (FOC, a novel extended proportional guidance (EPN law for intercepting the maneuvering target is proposed. In the first part, considering the memory function and filter characteristic of FOC, the novel extended PN guidance algorithm is developed based on the conventional PN after introducing the properties and operation rules of FOC. Further, with the help of FOC theory, the average load and ballistics characteristics of proposed guidance law are analyzed. Then, using the small offset kinematic model, the robustness of the new guidance law against autopilot parameters is studied theoretically by analyzing the sensitivity of the closed loop guidance system. At last, representative numerical results show that the designed guidance law obtains a better performance than the traditional PN for maneuvering target.

  3. Particle and X-ray damage in pn-CCDs

    CERN Document Server

    Meidinger, N; Strüder, L

    2000-01-01

    The fully depleted pn-junction charge coupled device (pn-CCD) has been developed as a detector for X-ray imaging and high-resolution spectroscopy for the X-ray satellite missions XMM and ABRIXAS. If the detector is exposed to a particle radiation environment, the energy resolution is degraded due to charge transfer losses and a dark current increase. In a first experiment, prototype devices were irradiated with 10 MeV protons. After completion of the detector development, the proton irradiation was repeated for a quantitative study of the radiation damage, relevant for the satellite missions. The irradiation test was extended by a 5.5 MeV alpha-particle and a 6 keV X-ray exposure of the pn-CCD, including the CAMEX preamplifier chip.

  4. The Oklahoma PN/ADN Articulation Project Report.

    Science.gov (United States)

    Oklahoma State Regents for Higher Education, Oklahoma City.

    In response to a critical nursing shortage in the state of Oklahoma, the Oklahoma Practical Nursing (PN)/Associate Degree Nursing (ADN) Articulation Project Coordinating Committee was formed in spring 1990 to develop a proposal for program articulation. A curriculum matrix was designed and adopted for use by five regional subcommittees which…

  5. Improving detection range via correlation of long PN codes

    Science.gov (United States)

    Subedi, Saurav; Wang, Zhonghai; Zheng, Y. Rosa

    2012-06-01

    This paper proposes a correlation method for detecting super-regenerative RF receivers via stimulation. Long PN sequences are used as to stimulate the unintended emissions from the RF receivers. High correlation between known PN sequence and stimulated unintended emissions from RF receivers helps improving the detection range compared to passive detection and power detection methods. Although RF receivers generate unintended emissions from their nonlinear devices, without stimulation, the power of these unintended emission is usually lower than --70dBm, as per the FCC regulations. Direct detection (passive detection) of these emissions is a challenging task specially in noisy conditions. When a stimulation signal is transmitted from distance, superregenerative receivers generate unintended emissions that contain the stimulation signal and its harmonics. Excellent correlation property of PN sequence enables us to improve the range and accuracy of detecting the super-regenerative receivers through stimulation method even in noisy conditions. The experiment involves detection of wireless doorbell, a commercially available super-regenerative receiver. USRP is used for transmitting the stimulant signal and receiving unintended stimulated emissions from the doorbell. Experiments show that the detection range of the proposed method with long PN sequences is much larger than passive detection and power detection methods.

  6. New PN Even Balanced Sequences for Spread-Spectrum Systems

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    Inácio JAL

    2005-01-01

    Full Text Available A new class of pseudonoise even balanced (PN-EB binary spreading sequences is derived from existing classical odd-length families of maximum-length sequences, such as those proposed by Gold, by appending or inserting one extra-zero element (chip to the original sequences. The incentive to generate large families of PN-EB spreading sequences is motivated by analyzing the spreading effect of these sequences from a natural sampling point of view. From this analysis a new definition for PG is established, from which it becomes clear that very high processing gains (PGs can be achieved in band-limited direct-sequence spread-spectrum (DSSS applications by using spreading sequences with zero mean, given that certain conditions regarding spectral aliasing are met. To obtain large families of even balanced (i.e., equal number of ones and zeros sequences, two design criteria are proposed, namely the ranging criterion (RC and the generating ranging criterion (GRC. PN-EB sequences in the polynomial range are derived using these criteria, and it is shown that they exhibit secondary autocorrelation and cross-correlation peaks comparable to the sequences they are derived from. The methods proposed not only facilitate the generation of large numbers of new PN-EB spreading sequences required for CDMA applications, but simultaneously offer high processing gains and good despreading characteristics in multiuser SS scenarios with band-limited noise and interference spectra. Simulation results are presented to confirm the respective claims made.

  7. Discontinuous pn-heterojunction for organic thin film transistors

    NARCIS (Netherlands)

    Cho, B.; Yu, S.H.; Kim, M.; Lee, M.H.; Huh, W.; Lee, J.; Kim, J.; Cho, J.H.; Lee, J.Y.; Song, Y.J.; Kang, M.S.

    2014-01-01

    Utilization of discontinuous pn-oragnic heterojunction is introduced as a versatile method to improve charge transport in organic thin film transistors (OTFTs). The method is demonstrated by depositing n-type dioctyl perylene tetracarboxylic diimide (PTCDI-C8) discontinuously onto base p-type

  8. Eccentric-orbit EMRI gravitational wave energy fluxes to 7PN order

    CERN Document Server

    Forseth, Erik; Hopper, Seth

    2015-01-01

    We present new results through 7PN order on the energy flux from eccentric extreme-mass-ratio binaries. The black hole perturbation calculations are made at very high accuracy (200 decimal places) using a Mathematica code based on the Mano-Suzuki-Takasugi (MST) analytic function expansion formalism. All published coefficients in the expansion through 3PN order are confirmed and new analytic and numeric terms are found to high order in $e^2$ at orders between 3.5PN and 7PN. We also show original work in finding (nearly) arbitrarily accurate expansions for hereditary terms at 1.5PN, 2.5PN, and 3PN orders. We fit to a model where at each PN order an eccentricity singular function is factored out, improving substantially the fit even as $e \\to 1$.

  9. New PN Even Balanced Sequences for Spread-Spectrum Systems

    Directory of Open Access Journals (Sweden)

    Inácio J. A. L.

    2005-01-01

    Full Text Available A new class of pseudonoise even balanced (PN-EB binary spreading sequences is derived from existing classical odd-length families of maximum-length sequences, such as those proposed by Gold, by appending or inserting one extra-zero element (chip to the original sequences. The incentive to generate large families of PN-EB spreading sequences is motivated by analyzing the spreading effect of these sequences from a natural sampling point of view. From this analysis a new definition for PG is established, from which it becomes clear that very high processing gains (PGs can be achieved in band-limited direct-sequence spread-spectrum (DSSS applications by using spreading sequences with zero mean, given that certain conditions regarding spectral aliasing are met. To obtain large families of even balanced (i.e., equal number of ones and zeros sequences, two design criteria are proposed, namely the ranging criterion (RC and the generating ranging criterion (GRC. PN-EB sequences in the polynomial range 3 ≤ n ≤ 6 are derived using these criteria, and it is shown that they exhibit secondary autocorrelation and cross-correlation peaks comparable to the sequences they are derived from. The methods proposed not only facilitate the generation of large numbers of new PN-EB spreading sequences required for CDMA applications, but simultaneously offer high processing gains and good despreading characteristics in multiuser SS scenarios with band-limited noise and interference spectra. Simulation results are presented to confirm the respective claims made.

  10. Contactless Microwave Characterization of Encapsulated Graphene p-n Junctions

    OpenAIRE

    Ranjan, Vishal; Zihlmann, Simon; Makk, Péter; Watanabe, Kenji; Taniguchi, Takashi; Schönenberger, Christian

    2017-01-01

    Accessing intrinsic properties of a graphene device can be hindered by the influence of contact electrodes. Here, we capacitively couple graphene devices to superconducting resonant circuits and observe clear changes in the resonance-frequency and -widths originating from the internal charge dynamics of graphene. This allows us to extract the density of states and charge relaxation resistance in graphene p-n junctions without the need of electrical contacts. The presented characterizations pa...

  11. A Pn Spreading Model Constrained with Observed Amplitudes in Asia

    Science.gov (United States)

    2011-09-01

    structure. For the Tibetan Plateau, a “plateau” province was defined as the region with a Moho depth deeper than 55 km. The “platform” and “shield...penetration depths below the Moho for different distances based on ray geometry and the Earth model used by Yang et al. (2007). My calculation...heterogeneities in the mantle lid and Moho topography on Pn geometric spreading, Bull. Seismol. Soc. Am. 101: 126–140, doi: 10.1785/0120100113. Bird, P

  12. A nanoscale pn junction in series with tunable Schottky barriers

    Science.gov (United States)

    Aspitarte, Lee; McCulley, Daniel R.; Minot, Ethan D.

    2017-10-01

    PN junctions in nanoscale materials are of interest for a range of technologies including photodetectors, solar cells, and light-emitting diodes. However, Schottky barriers at the interface between metal contacts and the nanomaterial are often unavoidable. The effect of metal-semiconductor interfaces on the behavior of nanoscale diodes must be understood, both to extract the characteristics of the pn junction, and to understand the overall characteristics of the final device. Here, we study the current-voltage characteristics of diodes that are formed in fully suspended carbon nanotubes (CNTs). We utilize tunable Schottky barrier heights at the CNT-metal interface to elucidate the role of the Schottky barriers on the device characteristics. We develop a quantitative model to show how a variety of device characteristics can arise from apparently similar devices. Using our model we extract key parameters of the Schottky barriers and the pn junction, and predict the overall I-V characteristics of the device. Our equivalent circuit model is relevant to a variety of nanomaterial-based diode devices that are currently under investigation.

  13. Electron transport through ac driven graphene p-n junctions

    Science.gov (United States)

    Zhang, Zhi-Qiang; Kang, Yan-Zhuo; Ding, Kai-He

    2018-02-01

    We study the electronic transport through ac driven graphene p-n junctions under a perpendicular magnetic field. It is found that subject to the transversely or longitudinally polarized ac field, in the p-n region, the conductance versus the on-site energy of the right electrode exhibits a characteristic structure with a zero value plateau and the followed oscillation peaks, whose widths are greatly suppressed by the ac field. In the n-n region, the conductance plateaus at G = (n + 1 / 2) (4e2 / h) (n is an integer) shrink for the transversely polarized ac field, whereas accompanied with the addition of the new quantized plateaus at G = n (4e2 / h) for the longitudinally polarized ac field. The combined influence of the ac field with the disorder can trigger a change in the mixing of the hole and electron states at the p-n interface, which leads to a destruction of the plateaus structure in the conductance versus the disorder strength with the emergence of new ones. The influence of the elliptically and circularly polarized ac field on the conductance is also shown.

  14. Prognostic Value of Preoperative Serum Levels of Periostin (PN) in Early Breast Cancer (BCa).

    Science.gov (United States)

    Nuzzo, Pier Vitale; Rubagotti, Alessandra; Argellati, Francesca; Di Meglio, Antonio; Zanardi, Elisa; Zinoli, Linda; Comite, Paola; Mussap, Michele; Boccardo, Francesco

    2015-07-28

    PN is a secreted cell adhesion protein critical for carcinogenesis. Elevated serum levels of PN have been implicated as playing an important role in different types of cancer, and a few reports suggest a potential role as a prognostic marker. We evaluated the prognostic significance of preoperative serum PN concentration in patients with BCa receiving curative surgery. Enzyme-Linked Immunosorbent Assay (ELISA) was performed to determine the preoperative serum PN level in 182 patients. The correlations between serum PN concentration with clinical pathological features and PN expression in primary tumor samples were analyzed. The prognostic impact of serum PN levels with all-cause and BCa-specific mortality was also investigated. Appropriate statistics were used. Elevated serum PN levels were significantly associated with patient age (p = 0.005), adjuvant systemic therapy (p = 0.04) and progesterone receptor (PgR) status (p = 0.02). No correlation between PN preoperative serum levels and other clinical-pathological parameters, including either the epithelial or the stromal PN expression of primary tumor or the combination of the two, was found. Similarly, no association between serum PN levels and either all-cause or BCa-specific mortality was found. However, subgroup analysis revealed a correlation between higher PN serum levels and all-cause mortality in patients with node-negative disease (p = 0.05) and in those with a low PgR expression (p = 0.03). Higher levels of serum PN were also found to correlate with BCa-specific mortality in the subgroup of patients who did not receive any adjuvant systemic therapy (p = 0.04). Our findings suggest that PN was detectable in the serum of early BCa patients before surgery and increased base-line serum levels predicted worse long-term survival outcomes in specific subgroups of patients.

  15. Prognostic Value of Preoperative Serum Levels of Periostin (PN in Early Breast Cancer (BCa

    Directory of Open Access Journals (Sweden)

    Pier Vitale Nuzzo

    2015-07-01

    Full Text Available PN is a secreted cell adhesion protein critical for carcinogenesis. Elevated serum levels of PN have been implicated as playing an important role in different types of cancer, and a few reports suggest a potential role as a prognostic marker. We evaluated the prognostic significance of preoperative serum PN concentration in patients with BCa receiving curative surgery. Enzyme-Linked Immunosorbent Assay (ELISA was performed to determine the preoperative serum PN level in 182 patients. The correlations between serum PN concentration with clinical pathological features and PN expression in primary tumor samples were analyzed. The prognostic impact of serum PN levels with all-cause and BCa-specific mortality was also investigated. Appropriate statistics were used. Elevated serum PN levels were significantly associated with patient age (p = 0.005, adjuvant systemic therapy (p = 0.04 and progesterone receptor (PgR status (p = 0.02. No correlation between PN preoperative serum levels and other clinical-pathological parameters, including either the epithelial or the stromal PN expression of primary tumor or the combination of the two, was found. Similarly, no association between serum PN levels and either all-cause or BCa-specific mortality was found. However, subgroup analysis revealed a correlation between higher PN serum levels and all-cause mortality in patients with node-negative disease (p = 0.05 and in those with a low PgR expression (p = 0.03. Higher levels of serum PN were also found to correlate with BCa-specific mortality in the subgroup of patients who did not receive any adjuvant systemic therapy (p = 0.04. Our findings suggest that PN was detectable in the serum of early BCa patients before surgery and increased base-line serum levels predicted worse long-term survival outcomes in specific subgroups of patients.

  16. Crystal Growth and Characterization of the Narrow-Band-Gap Semiconductors OsPn 2 (Pn = P, As, Sb)

    Energy Technology Data Exchange (ETDEWEB)

    Bugaris, Daniel E.; Malliakas, Christos D.; Shoemaker, Daniel P.; Do, Dat T.; Chung, Duck Young; Mahanti, Subhendra D.; Kanatzidis, Mercouri G.

    2014-09-15

    Using metal fluxes, crystals of the binary osmium dipnictides OsPn(2) (Pn = P, As, Sb) have been grown for the first time. Single-crystal X-ray diffraction confirms that these compounds crystallize in the marcasite structure type with orthorhombic space group Pnnm. The structure is a three-dimensional framework of corner- and edge-sharing OsPn(6) octahedra, as well as [Pn(2)(-4)] anions. Raman spectroscopy shows the presence of PP single bonds, consistent with the presence of [Pn(2)(-4)] anions and formally Os4+ cations. Optical-band-gap and high-temperature electrical resistivity measurements indicate that these materials are narrow-band-gap semiconductors. The experimentally determined Seebeck coefficients reveal that nominally undoped OsP2 and OsSb2 are n-type semiconductors, whereas OsAs2 is p-type. Electronic band structure using density functional theory calculations shows that these compounds are indirect narrow-band-gap semiconductors. The bonding p orbitals associated with the Pn(2) dimer are below the Fermi energy, and the corresponding antibonding states are above, consistent with a PnPn single bond. Thermopower calculations using Boltzmann transport theory and constant relaxation time approximation show that these materials are potentially good thermoelectrics, in agreement with experiment.

  17. Reinventing the PN Junction: Dimensionality Effects on Tunneling Switches

    Science.gov (United States)

    2012-05-11

    state tunneling probability is 10-6. 2.3.2 Conclusion This device exploits a unique heterostructure and surface quantum well to create a new...pn junction describes tunneling [9] within a nanowire or carbon nanotube junction as schematically represented in Figure 6.3(a). Tunneling is...6.5 0D-1D JUNCTION A 0d to 1d junction represents tunneling from a quantum dot to a nanowire as shown in Figure 6.6(a). Our main goal in analyzing

  18. Bio-inspired nanostructures for implementing vertical pn-junctions

    KAUST Repository

    Saffih, Faycal

    2011-08-04

    An apparatus, system, and method having a 3D pn-junction structure are presented. One embodiment of an apparatus includes a substrate, a first doped structure, and a second doped structure. In one embodiment, the first doped structure has a first doping type. The first doped structure may be formed above the substrate and extend outwardly from an upper surface of the substrate. In one embodiment, the second doped structure has a second doping type. The second doped structure may be formed above the substrate and in contact with the first doped structure. Additionally, the second doped structure may extend outwardly from the upper surface of the substrate.

  19. Ion implanted GaAs nanowire pn junctions

    Energy Technology Data Exchange (ETDEWEB)

    Wegener, Katharina; Stichtenoth, Daniel; Ronning, Carsten [II. Institute of Physics, University of Goettingen (Germany); Gutsche, Christoph; Prost, Werner; Tegude, Franz Josef [Solid-State Electronics Department, University of Duisburg-Essen (Germany)

    2008-07-01

    Ion beam doping of materials offers advantages in comparison to doping during growth or by diffusion. First, the impurity concentration as well as the lateral and depth distributions of the dopants are precisely controllable, and secondly, almost all elements can be implanted isotope-selective even beyond any solubility limit. We present studies on ion implanted gallium arsenide (GaAs) nanowire pn junctions. Nominal intrinsic GaAs nanowires were grown by the vapour-liquid-solid mechanism using gold nanoparticles on top of GaAs(100) substrates. Sulphur, being a donor in GaAs, was implanted into the nanowires using different ion energies resulting in a uniform concentration profile. The now n-type doped nanowires were then reinserted into the metal organic vapour phase epitaxy system. After an annealing procedure, the growth of the nanowires was continued under the addition of an acceptor. Finally, the fabricated nanowire pn junctions were shaved from the growth substrate and processed with contacts on top of insulating carrier substrates. First results on the electrical characterization of these structures are shown.

  20. Partial correlation properties of pseudonoise /PN/ codes in noncoherent synchronization/detection schemes

    Science.gov (United States)

    Cartier, D. E.

    1976-01-01

    This concise paper considers the effect on the autocorrelation function of a pseudonoise (PN) code when the acquisition scheme only integrates coherently over part of the code and then noncoherently combines these results. The peak-to-null ratio of the effective PN autocorrelation function is shown to degrade to the square root of n, where n is the number of PN symbols over which coherent integration takes place.

  1. Electrical/thermal transport and electronic structure of the binary cobalt pnictides CoPn2 (Pn = As and Sb

    Directory of Open Access Journals (Sweden)

    Yosuke Goto

    2015-06-01

    Full Text Available We demonstrate the electrical and thermal transport properties of polycrystalline CoPn2 (Pn = As and Sb between 300 and 900 K. CoAs2 shows semiconducting electrical transport up to 900 K, while CoSb2 exhibits degenerate conduction. Sign inversion of the Seebeck coefficient is observed at ∼310 and ∼400 K for CoAs2 and CoSb2, respectively. Thermal conductivity at 300 K is 11.7 Wm−1K−1 for CoAs2 and 9.4 Wm−1K−1 for CoSb2. The thermoelectric power factor of CoAs2 is ∼10 μWcm−1K−2, although the dimensionless figure of merit is limited to ∼0.1 due to relatively high thermal conductivity. Using electronic structure calculations, the band gap value is calculated to be 0.55 eV for CoAs2 and 0.26 eV for CoSb2.

  2. Focusing RKKY interaction by graphene P-N junction

    Science.gov (United States)

    Zhang, Shu-Hui; Zhu, Jia-Ji; Yang, Wen; Chang, Kai

    2017-09-01

    The carrier-mediated RKKY interaction between local spins plays an important role for the application of magnetically doped graphene in spintronics and quantum computation. Previous studies largely concentrate on the influence of electronic states of uniform systems on the RKKY interaction. Here we reveal a very different way to manipulate the RKKY interaction by showing that the anomalous focusing—a well-known electron optics phenomenon in graphene P-N junctions—can be utilized to refocus the massless Dirac electrons emanating from one local spin to the other local spin. This gives rise to rich spatial interference patterns and symmetry-protected non-oscillatory RKKY interaction with a strongly enhanced magnitude. It may provide a new way to engineer the long-range spin-spin interaction in graphene.

  3. Nanofibrous p-n Junction and Its Rectifying Characteristics

    Directory of Open Access Journals (Sweden)

    Jian Fang

    2013-01-01

    Full Text Available Randomly oriented tin oxide (SnO2 nanofibers and poly(3,4-ethylenedioxythiophene-poly(styrenesulfonate/polyvinylpyrrolidone (PEDOT:PSS/PVP nanofibers were prepared by a two-step electrospinning technique to form a layered fibrous mat. The current-voltage measurement revealed that the fibrous mat had an obvious diode-rectifying characteristic. The thickness of the nanofiber layers was found to have a considerable influence on the device resistance and rectifying performance. Such an interesting rectifying property was attributed to the formation of a p-n junction between the fibrous SnO2 and PEDOT:PSS/PVP layers. This is the first report that a rectifying junction can be formed between two layers of electrospun nanofiber mats, and the resulting nanofibrous diode rectifier may find applications in sensors, energy harvest, and electronic textiles.

  4. Rectifying behaviour of spin coated pn hetero-junction

    Energy Technology Data Exchange (ETDEWEB)

    Yogamalar, N. Rajeswari; Bose, A. Chandra, E-mail: acbose@nitt.edu [Nanomaterials Laboratory, Department of Physics, National Institute of Technology, Tiruchirappalli – 620 015 (India)

    2015-06-24

    Rectifying pn hetero- junction is fabricated with an acceptor p-type organic semiconductor namely tetra- chloro dihydroxy tetra-iodo fluorescein (Rose Bengal (RB)) followed by an inorganic n-type ZnO semiconductor on indium tin oxide (ITO) substrate. The n-type ZnO films are formed by unintentional doping and doping with aluminium (Al) and yttrium (Y) donors. The surface morphology and the distribution of grains are observed from scanning electron microscopy (SEM) and atomic force microscopy (AFM). The current-voltage (I-V) characteristic of the rectifying diode is measured to characterize the junction properties. The I-V plots obtained from the hetero- junction with electric contact shows a diode characteristic different from that of an ideal behavior. The overall efficiency of the diode exhibits a greater dependency on the film crystallinity, carrier concentration, and reverse saturation current.

  5. Low-fat, high-carbohydrate parenteral nutrition (PN) may potentially reverse liver disease in long-term PN-dependent infants

    DEFF Research Database (Denmark)

    Jakobsen, Marianne Skytte; Jørgensen, Marianne Hørby; Husby, Steffen

    2015-01-01

    INTRODUCTION: Parenteral nutrition-associated cholestasis (PNAC) is a complication of long-term parenteral nutrition (PN). Removal of lipids may reverse PNAC but compromises the energy to ensure infant growth. The purpose of this study was to test whether a low-fat, high-carbohydrate PN regimen......, which prevents and reverses PNAC in adults, could do the same in infants. This regimen could potentially avoid the problem of diminished energy input after removing nutritional lipids. METHODS: Infants developing PNAC over a 2-year period were started on a low-fat PN regimen with calories primarily from...... carbohydrates. The fat-free PN, containing 314 kJ/ml, was provided 5-6 times a week and fat, including essential fatty acids and fat-soluble vitamins, 1-2 times a week. Enteral feeding was continued according to individual tolerance. RESULTS: The study included 10 infants with short bowel syndrome (six...

  6. Unified Model for P-N Junction Current-Voltage Characteristics

    OpenAIRE

    Cristea, Miron J.

    2009-01-01

    The current-voltage p-n junction characteristics were mainly analyzed until now at low injection levels and high level injection separately. This work unifies the low injection, medium injection, high injection levels and the ohmic region of the I/V characteristics. Keywords: p-n junctions, current-voltage characteristics, low injection and high injection levels, ohmic region.

  7. A new class of PN3-pincer ligands for metal–ligand cooperative catalysis

    KAUST Repository

    Li, Huaifeng

    2014-12-01

    Work on a new class of PN3-pincer ligands for metal-ligand cooperative catalysis is reviewed. While the field of the pyridine-based PN3-transition metal pincer complexes is still relatively young, many important applications of these complexes have already emerged. In several cases, the PN3-pincer complexes for metal-ligand cooperative catalysis result in significantly improved or unprecedented activities. The synthesis and coordination chemistry of PN3-pincer ligands are briefly summarized first to cover the synthetic routes for their preparation, followed by a focus review on their applications in catalysis. A specific emphasis is placed on the later section about the role of PN3-pincer ligands\\' dearomatization-rearomatization steps during the catalytic cycles. The mechanistic insights from density functional theory (DFT) calculations are also discussed.

  8. Gas Sensors Based on Ceramic p-n Heterocontacts

    Energy Technology Data Exchange (ETDEWEB)

    Aygun, Seymen Murat [Iowa State Univ., Ames, IA (United States)

    2005-01-01

    Ceramic p-n heterocontacts based on CuO/ZnO were successfully synthesized and a systematic study of their hydrogen sensitivity was conducted. The sensitivity and response rates of CuO/ZnO sensors were studied utilizing current-voltage, current-time, and impedance spectroscopy measurements. The heterocontacts showed well-defined rectifying characteristics and were observed to detect hydrogen via both dc and ac measurements. Surface coverage data were derived from current-time measurements which were then fit to a two-site Langmuir adsorption model quite satisfactorily. The fit suggested that there should be two energetically different adsorption sites in the system. The heterocontacts were doped in an attempt to increase the sensitivity and the response rate of the sensor. First, the effects of doping the p-type (CuO) on the sensor characteristics were investigated. Doping the p-type CuO with both acceptor and isovalent dopants greatly improved the hydrogen sensitivity. The sensitivity of pure heterocontact observed via I-V measurements was increased from ~2.3 to ~9.4 with Ni doping. Dopants also enhanced the rectifying characteristics of the heterocontacts. Small amounts of Li addition were shown to decrease the reverse bias (saturation) current to 0.2 mA at a bias level of -5V. No unambiguous trends were observed between the sensitivity, the conductivity, and the density of the samples. Comparing the two phase microstructure to the single phase microstructure there was no dramatic increase in the sensitivity. Kinetic studies also confirmed the improved sensor characteristics with doping. The dopants decreased the response time of the sensor by decreasing the response time of one of the adsorption sites. The n-type ZnO was doped with both acceptor and donor dopants. Li doping resulted in the degradation of the p-n junction and the response time of the sensor. However, the current-voltage behavior of Ga-doped heterocontacts showed the best rectifying characteristics

  9. Titanium-dioxide nanotube p-n homojunction diode

    Energy Technology Data Exchange (ETDEWEB)

    Alivov, Yahya, E-mail: y.alivov@colorado.edu, E-mail: pnagpal@colorado.edu; Ding, Yuchen; Singh, Vivek [Department of Chemical and Biological Engineering, University of Colorado Boulder, 3415 Colorado Avenue, Boulder, Colorado 80303 (United States); Nagpal, Prashant, E-mail: y.alivov@colorado.edu, E-mail: pnagpal@colorado.edu [Department of Chemical and Biological Engineering, University of Colorado Boulder, 3415 Colorado Avenue, Boulder, Colorado 80303 (United States); Materials Science and Engineering, University of Colorado Boulder, 3415 Colorado Avenue, Boulder, Colorado 80303 (United States); Renewable and Sustainable Energy Institute, University of Colorado Boulder, 2445 Kittredge Loop, Boulder, Colorado 80309 (United States)

    2014-12-29

    Application of semiconductors in functional optoelectronic devices requires precise control over their doping and formation of junction between p- and n-doped semiconductors. While doped thin films have led to several semiconductor devices, need for high-surface area nanostructured devices for photovoltaic, photoelectrochemical, and photocatalytic applications has been hindered by lack of desired doping in nanostructures. Here, we show titanium-dioxide (TiO{sub 2}) nanotubes doped with nitrogen (N) and niobium (Nb) as acceptors and donors, respectively, and formation of TiO{sub 2} nanotubes p-n homojunction. This TiO{sub 2}:N/TiO{sub 2}:Nb homojunction showed distinct diode-like behaviour with rectification ratio of 1115 at ±5 V and exhibited good photoresponse for ultraviolet light (λ = 365 nm) with sensitivity of 0.19 A/W at reverse bias of −5 V. These results can have important implications for development of nanostructured metal-oxide solar-cells, photodiodes, LED's, photocatalysts, and photoelectrochemical devices.

  10. Ionic PN and PNP junctions -- Diodes and Transistors

    Science.gov (United States)

    Kalman, Eric; Vlassiouk, Ivan; Apel, Pavel; Siwy, Zuzanna

    2008-03-01

    There are well-known devices for controlling the transport of electrons, but very few control ions in a solution. We have prepared ionic diodes and transistors that function in a similar manner to their semiconductor analogues. Ionic PN junctions were created by surface patterning single conical nanopores in polymer films, so that the pore walls are split into two sections: one with positive charge, and the other with negative. These diodes can achieve rectification degrees of several hundreds. Ionic PNP junctions were created by surface patterning single double-conical nanopores in polymer films with tip diameter between 2 and 6 nm, so that the pore walls are split into three sections: the two areas near the large pore openings which are positively charged, while the center of the pore, near the pore tip, is negatively charged. This device works in a similar fashion to a semiconducting BJT transistor, and we show that we can control the electric potential chemically in a manner sufficient to gate the ion current through the device.

  11. 2PN light propagation and measurement in the solar system

    Science.gov (United States)

    Deng, X.-M.; Huang, T.-Y.

    2011-10-01

    As a sensitive and useful tool in gravitational physics, especially for some high order effects, the propagation of light carries lots of information about the nature of spacetime and plays an important role in high- precision experiments and measurements. Three methods can be used in this issue. First is mainly developed by Kopeikin & Schafer (1999) and Kopeikin & Makarov (2007) and so on. Second is mainly developed by Brumberg (1991) and Klioner & Kopeikin (1992) and so on. Recently, Linet & Teyssandier (2002) and Le Poncin-Lafitte & Teyssandier (2008) and others used Synge's world function to investigate the light propagation avoiding the integration of geodesic equations. We adopt the second one. In this paper, the second post-Newtonian (2PN) framework for light propagation is developed with two additional parameters σ and η besides the two parameterized post-Newtonian (PPN) parameters γ and β. For a precision level of a few microarcsecond for space astrometry missions in the near future, started from the definition of a measurable quantity, a gauge-invariant angle between the directions of two incoming photons for a differential measurement in astrometric observation is discussed.

  12. Upper mantle structure at Walvis Ridge from Pn tomography

    Science.gov (United States)

    Ryberg, Trond; Braeuer, Benjamin; Weber, Michael

    2017-10-01

    Passive continental margins offer the unique opportunity to study the processes involved in continental extension and break-up. Within the LISPWAL (LIthospheric Structure of the Namibian continental Passive margin at the intersection with the Walvis Ridge from amphibious seismic investigations) project, combined on- and offshore seismic experiments were designed to characterize the Southern African passive margin at the Walvis Ridge in northern Namibia. In addition to extensive analysis of the crustal structures, we carried out seismic investigations targeting the velocity structure of the upper mantle in the landfall region of the Walvis Ridge with the Namibian coast. Upper mantle Pn travel time tomography from controlled source, amphibious seismic data was used to investigate the sub-Moho upper mantle seismic velocity. We succeeded in imaging upper mantle structures potentially associated with continental break-up and/or the Tristan da Cunha hotspot track. We found mostly coast-parallel sub-Moho velocity anomalies, interpreted as structures which were created during Gondwana break-up.

  13. Atomically thin p-n junctions with van der Waals heterointerfaces.

    Science.gov (United States)

    Lee, Chul-Ho; Lee, Gwan-Hyoung; van der Zande, Arend M; Chen, Wenchao; Li, Yilei; Han, Minyong; Cui, Xu; Arefe, Ghidewon; Nuckolls, Colin; Heinz, Tony F; Guo, Jing; Hone, James; Kim, Philip

    2014-09-01

    Semiconductor p-n junctions are essential building blocks for electronic and optoelectronic devices. In conventional p-n junctions, regions depleted of free charge carriers form on either side of the junction, generating built-in potentials associated with uncompensated dopant atoms. Carrier transport across the junction occurs by diffusion and drift processes influenced by the spatial extent of this depletion region. With the advent of atomically thin van der Waals materials and their heterostructures, it is now possible to realize a p-n junction at the ultimate thickness limit. Van der Waals junctions composed of p- and n-type semiconductors--each just one unit cell thick--are predicted to exhibit completely different charge transport characteristics than bulk heterojunctions. Here, we report the characterization of the electronic and optoelectronic properties of atomically thin p-n heterojunctions fabricated using van der Waals assembly of transition-metal dichalcogenides. We observe gate-tunable diode-like current rectification and a photovoltaic response across the p-n interface. We find that the tunnelling-assisted interlayer recombination of the majority carriers is responsible for the tunability of the electronic and optoelectronic processes. Sandwiching an atomic p-n junction between graphene layers enhances the collection of the photoexcited carriers. The atomically scaled van der Waals p-n heterostructures presented here constitute the ultimate functional unit for nanoscale electronic and optoelectronic devices.

  14. Long-term survival of patients with pN2 lung cancer according to the pattern of lymphatic spread.

    Science.gov (United States)

    Legras, Antoine; Mordant, Pierre; Arame, Alex; Foucault, Christophe; Dujon, Antoine; Le Pimpec Barthes, Françoise; Riquet, Marc

    2014-04-01

    N2 involvement has dramatic consequences on the prognosis and management of patients with non-small cell lung cancer (NSCLC). N2-NSCLC may present with or without N1 involvement, constituting non-skip (pN1N2) and skip (pN0N2) diseases, respectively. As the prognostic impact of this subclassification is still a matter of debate, we analyzed the prognosis of pN2 patients according to the pN1-involvement and the number of N2-stations concerned. The medical records of consecutive patients who underwent surgery for pN2-NSCLC in 2 French centers between 1980 and 2009 were prospectively collected and retrospectively reviewed. Patients undergoing induction therapy, exploratory thoracotomy, incomplete mediastinal lymphadenectomy, or incomplete resections were excluded. The prognoses of pN1N2 and pN0N2 patients were first compared, and then deciphered according to the number of N2 stations involved (single-station: 1S, multi-station: 2S). All together, 871 patients underwent first-line complete surgical resection for pN2-NSCLC during the study period, including 258 pN0N2 (29.6%) and 613 pN1N2 (70.4%) patients. Mean follow-up was 72.8±48 months. Median, 5- and 10-year survivals were, respectively, 30 months, 34%, and 24% for pN0N2 and 20 months, 21%, and 14% for pN1N2 patients (p<0.001). Multivariate analysis revealed 3 different prognostic groups; ie, favorable in pN0N2-1S disease, intermediate in pN0N2-2S and pN1N2-1S diseases, and poor in pN1N2-2S disease (p<0.001). Among pN2 patients, the combination of N1 involvement (pN0N2 vs pN1N2) and number of involved N2 stations (1S vs 2S) are independent prognostic factors. These results might be taken into consideration to sub-classify the heterogeneous pN2-NSCLC group of patients. Copyright © 2014 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

  15. PnET-BGC: Modeling Biogeochemical Processes in a Northern Hardwood Forest Ecosystem

    Data.gov (United States)

    National Aeronautics and Space Administration — This archived model product contains the directions, executables, and procedures for running PnET-BGC to recreate the results of: Gbondo-Tugbawa, S.S., C.T. Driscoll...

  16. PnET-BGC: Modeling Biogeochemical Processes in a Northern Hardwood Forest Ecosystem

    Data.gov (United States)

    National Aeronautics and Space Administration — ABSTRACT: This archived model product contains the directions, executables, and procedures for running PnET-BGC to recreate the results of: Gbondo-Tugbawa, S.S.,...

  17. Locally hydrazine doped WSe2 p-n junction toward high-performance photodetectors

    Science.gov (United States)

    Sun, Mengxing; Xie, Dan; Sun, Yilin; Li, Weiwei; Ren, Tianling

    2018-01-01

    Two dimensional (2D) materials have shown great potential in the photodetection and other optoelectronic applications. Exploiting 2D materials to form p-n junctions enables effective generation and separation of carriers excited by light, thus creating high-performance optoelectronic devices. This paper demonstrates a lateral WSe2 p-n junction through a locally hydrazine doping method. Good current-rectifying characteristics, including a high rectification ratio of ∼103, have been observed; this indicates that a high-quality p-n junction has been formed by chemical doping. Under light illumination, the device shows improved photoresponse capabilities with a responsivity of 30 mA W‑1, a detectivity of 6.18 × 108 Jones, photocurrent/dark current ratio of 103 and a response time of 2 ms. These results suggest an effective way to get a p-n junction and reveal the application potential of the device for next generation photodetectors.

  18. Single gate p-n junctions in graphene-ferroelectric devices

    Energy Technology Data Exchange (ETDEWEB)

    Hinnefeld, J. Henry; Mason, Nadya, E-mail: nadya@illinois.edu [Department of Physics, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801 (United States); Xu, Ruijuan; Pandya, Shishir; Martin, Lane W. [Department of Materials Science and Engineering, University of California, Berkeley, California 94720 (United States); Materials Science Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Rogers, Steven; Shim, Moonsub [Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801 (United States)

    2016-05-16

    Graphene's linear dispersion relation and the attendant implications for bipolar electronics applications have motivated a range of experimental efforts aimed at producing p-n junctions in graphene. Here we report electrical transport measurements of graphene p-n junctions formed via simple modifications to a PbZr{sub 0.2}Ti{sub 0.8}O{sub 3} substrate, combined with a self-assembled layer of ambient environmental dopants. We show that the substrate configuration controls the local doping region, and that the p-n junction behavior can be controlled with a single gate. Finally, we show that the ferroelectric substrate induces a hysteresis in the environmental doping which can be utilized to activate and deactivate the doping, yielding an “on-demand” p-n junction in graphene controlled by a single, universal backgate.

  19. Comparison of the pp → π+pn and pp → π+d production rates

    Science.gov (United States)

    Fäldt, G.; Wilkin, C.

    2017-07-01

    Fully constrained bubble chamber data on the pp →π+ pn and pp →π+ d reactions are used to investigate the ratio of the counting rates for the two processes at low pn excitation energies. Whereas the ratio is in tolerable agreement with that found in a high resolution spectrometer experiment, the angular distribution in the final pn rest frame shows that the deviation from the predictions of final state interaction theory must originate primarily from higher partial waves in the pn system. These considerations might also be significant for the determination of the S-wave Λp scattering length from data on the pp →K+ Λp reaction.

  20. PnET Models: Carbon, Nitrogen, Water Dynamics in Forest Ecosystems (Vers. 4 and 5)

    Data.gov (United States)

    National Aeronautics and Space Administration — PnET (Photosynthetic / EvapoTranspiration model) is a nested series of models of carbon, water, and nitrogen dynamics in forest ecosystems. The models can be used to...

  1. PnET Models: Carbon, Nitrogen, Water Dynamics in Forest Ecosystems (Vers. 4 and 5)

    Data.gov (United States)

    National Aeronautics and Space Administration — ABSTRACT: PnET (Photosynthetic / EvapoTranspiration model) is a nested series of models of carbon, water, and nitrogen dynamics in forest ecosystems. The models can...

  2. The Influence of Neocate in Paediatric Short Bowel Syndrome on PN Weaning

    Directory of Open Access Journals (Sweden)

    E. De Greef

    2010-01-01

    Full Text Available Clinical management of short bowel syndrome remains a multistage process. Although PN is crucial, early introduction of enteral feeding is mandatory. We describe retrospectively 4 patients with an ultrashort bowel who could be weaned off PN on very short terms after introduction of an amino-acid-based formula (Neocate. Patient 1 had congenital short bowel with 50 cm small bowel and 30 cm colon. He had persistent diarrhoea on a semielementary formula. When Neocate was introduced he could be weaned from PN within 6 months. Patient 2 needed multiple surgical interventions because of NEC at D 27. He maintained 40 cm small bowel and an intact colon and remained PN dependent on semielemental formula. After introducing Neocate, PN could be weaned within 3 months. In the next 2 patients, Neocate was introduced as initial enteral feeding after bowel resection following antenatal midgut volvulus. Patient 3 had 20 cm small bowel and an intact colon. PN was weaned after 2 months. Patient 4 had 9 cm small bowel and an intact colon. PN was weaned after 13 months. In all patients Ileocaecal valve (ICV was preserved. No consensus is reached on the type of formula to use for short bowel syndrome. Compared to recent data in the literature, the weaning period in these 4 patients was significantly shortened on an aminoacid based formula. The reason for this may lie in the antiallergic properties of this formula. We recommend the use of an amino-acid-based formula to induce earlier weaning of PN.

  3. Optoelectronic devices based on electrically tunable p-n diodes in a monolayer dichalcogenide

    Science.gov (United States)

    Baugher, Britton W. H.; Churchill, Hugh O. H.; Yang, Yafang; Jarillo-Herrero, Pablo

    2014-04-01

    The p-n junction is the functional element of many electronic and optoelectronic devices, including diodes, bipolar transistors, photodetectors, light-emitting diodes and solar cells. In conventional p-n junctions, the adjacent p- and n-type regions of a semiconductor are formed by chemical doping. Ambipolar semiconductors, such as carbon nanotubes, nanowires and organic molecules, allow for p-n junctions to be configured and modified by electrostatic gating. This electrical control enables a single device to have multiple functionalities. Here, we report ambipolar monolayer WSe2 devices in which two local gates are used to define a p-n junction within the WSe2 sheet. With these electrically tunable p-n junctions, we demonstrate both p-n and n-p diodes with ideality factors better than 2. Under optical excitation, the diodes demonstrate a photodetection responsivity of 210 mA W-1 and photovoltaic power generation with a peak external quantum efficiency of 0.2%, promising values for a nearly transparent monolayer material in a lateral device geometry. Finally, we demonstrate a light-emitting diode based on monolayer WSe2. These devices provide a building block for ultrathin, flexible and nearly transparent optoelectronic and electronic applications based on ambipolar dichalcogenide materials.

  4. Synthesis and characterization of p-n homojunction-containing zinc oxide nanowires

    Science.gov (United States)

    Li, Guohua; Sundararajan, Abhishek; Mouti, Anas; Chang, Yao-Jen; Lupini, Andrew R.; Pennycook, Stephen J.; Strachan, Douglas R.; Guiton, Beth S.

    2013-02-01

    We illustrate a simple method to synthesize highly ordered ZnO axial p-n homojunction-containing nanowires using a low temperature method, and on a variety of substrates. X-ray diffraction, scanning transmission electron microscopy, scanning electron microscopy, and Raman spectroscopy are used to reveal high quality single-crystalline wires with a [001] growth direction. The study of electrical transport through a single nanowire based device and cathodoluminescence via scanning transmission electron microscopy demonstrates that an axial p-n junction exists within each ZnO nanowire. This represents the first low temperature synthesis of axial p-n homojunction-containing ZnO nanowires with uniform and controllable diameters.We illustrate a simple method to synthesize highly ordered ZnO axial p-n homojunction-containing nanowires using a low temperature method, and on a variety of substrates. X-ray diffraction, scanning transmission electron microscopy, scanning electron microscopy, and Raman spectroscopy are used to reveal high quality single-crystalline wires with a [001] growth direction. The study of electrical transport through a single nanowire based device and cathodoluminescence via scanning transmission electron microscopy demonstrates that an axial p-n junction exists within each ZnO nanowire. This represents the first low temperature synthesis of axial p-n homojunction-containing ZnO nanowires with uniform and controllable diameters. Electronic supplementary information (ESI) available. See DOI: 10.1039/c3nr31639d

  5. Synthesis and structural characterization of the Zintl phases Na{sub 3}Ca{sub 3}TrPn{sub 4}, Na{sub 3}Sr{sub 3}TrPn{sub 4}, and Na{sub 3}Eu{sub 3}TrPn{sub 4} (Tr=Al, Ga, In; Pn=P, As, Sb)

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Yi [Department of Chemistry & Biochemistry, University of Delaware, 304A Drake Hall, Newark, DE 19716 (United States); Suen, Nian-Tzu [Department of Chemistry & Biochemistry, University of Delaware, 304A Drake Hall, Newark, DE 19716 (United States); College of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou 225002 (China); Kunene, Thabiso; Stoyko, Stanislav [Department of Chemistry & Biochemistry, University of Delaware, 304A Drake Hall, Newark, DE 19716 (United States); Bobev, Svilen, E-mail: bobev@udel.edu [Department of Chemistry & Biochemistry, University of Delaware, 304A Drake Hall, Newark, DE 19716 (United States)

    2017-05-15

    15 new quaternary Zintl phases have been synthesized by solid-state reactions from the respective elements, and their structures have been determined by single-crystal X-ray diffraction. Na{sub 3}E{sub 3}TrPn{sub 4} (E=Ca, Sr, Eu; Tr=Al, Ga, In; Pn=P, As, Sb) crystallize in the hexagonal crystal system with the non-centrosymmetric space group P6{sub 3}mc (No. 186). The structure represents a variant of the K{sub 6}HgS{sub 4} structure type (Pearson index hP22) and features [TrPn{sub 4}]{sup 9–} tetrahedral units, surrounded by Na{sup +} and Ca{sup 2+}, Sr{sup 2+}, Eu{sup 2+} cations. The nominal formula rationalization [Na{sup +}]{sub 3}[E{sup 2+}]{sub 3}[TrPn{sub 4}]{sup 9–} follows the octet rule, suggesting closed-shell configurations for all atoms and intrinsic semiconducting behavior. However, structure refinements for several members hint at disorder and mixing of cations that potentially counteract the optimal valence electron count. - Graphical abstract: The hexagonal, non-centrosymmetric structure of Na{sub 3}E{sub 3}TrPn{sub 4} (E=Ca, Sr, Eu; Tr=Al, Ga, In; Pn=P, As, Sb) features [TrPn{sub 4}]{sup 9–} tetrahedral units, surrounded by Na{sup +} and Ca{sup 2+}, Sr{sup 2+}, Eu{sup 2+} cations. - Highlights: • 15 quaternary phosphides, arsenides, and antimonides are synthesized and structurally characterized. • The structure is a variant of the hexagonal K{sub 6}HgS{sub 4}-type, with distinctive pattern for the cations. • Occupational and/or positional disorder of yet unknown origin exists for some members of the series.

  6. The photoirradiation induced p-n junction in naphthylamine-based organic photovoltaic cells.

    Science.gov (United States)

    Bai, Linyi; Gao, Qiang; Xia, Youyi; Ang, Chung Yen; Bose, Purnandhu; Tan, Si Yu; Zhao, Yanli

    2015-09-21

    The bulk heterojunction (BHJ) plays an indispensable role in organic photovoltaics, and thus has been investigated extensively in recent years. While a p-n heterojunction is usually fabricated using two different donor and acceptor materials such as poly(3-hexylthiophene-2,5-diyl) (P3HT) and phenyl-C61-butyric acid methyl ester (PCBM), it is really rare that such a BHJ is constructed by a single entity. Here, we presented a photoirradiation-induced p-n heterojunction in naphthylamine-based organic photovoltaic cells, where naphthylamine as a typical p-type semiconductor could be oxidized under photoirradiation and transformed into a new semiconductor with the n-type character. The p-n heterojunction was realized using both the remaining naphthylamine and its oxidative product, giving rise to the performance improvement in organic photovoltaic devices. The experimental results show that the power conversion efficiency (PCE) of the devices could be achieved up to 1.79% and 0.43% in solution and thin film processes, respectively. Importantly, this technology using naphthylamine does not require classic P3HT and PCBM to realize the p-n heterojunction, thereby simplifying the device fabrication process. The present approach opens up a promising route for the development of novel materials applicable to the p-n heterojunction.

  7. Electronic structure and transport properties of Ba{sub 2}Cd{sub 2}Pn{sub 3} (Pn = As and Sb): An efficient materials for energy conversion

    Energy Technology Data Exchange (ETDEWEB)

    Reshak, A.H., E-mail: maalidph@yahoo.co.uk [New Technologies - Research Centre, University of West Bohemia, Univerzitni 8, 306 14 Pilsen (Czech Republic); Center of Excellence Geopolymer and Green Technology, School of Material Engineering, University Malaysia Perlis, 01007 Kangar, Perlis (Malaysia)

    2016-06-15

    The full potential method within the recently modified Becke-Johnson potential explore that the Ba{sub 2}Cd{sub 2}Pn{sub 3} (Pn = As and Sb) compounds are narrow band gap semiconductors of about 0.49 and 0.32 eV, which confute the finding of the previous TB-LMTO-ASA calculation that Ba{sub 2}Cd{sub 2}Sb{sub 3} is a poor metal. It has been found that there are subtle difference in band desperations of the two compounds, resulting in significant influence on the electronic and transport properties, taking into account the size and the electro-negativity differences between As and Sb atoms. Calculation show that there exists a strong hybridization between the orbitals which may lead to form covalent bonding which is more favorable for the transport of the carriers than ionic one. The electronic structure, the anisotropy and the inter-atomic interactions are further analyzed by calculating the valence electronic charge density distribution in two crystallographic planes. The semi-classical Boltzmann theory as incorporated in BoltzTraP code was used to calculate the transport properties of Ba{sub 2}Cd{sub 2}As{sub 3} and Ba{sub 2}Cd{sub 2}Sb{sub 3} at different temperatures and chemical potentials to ascertain the influence of temperatures and substituting As by Sb on the transport properties. The carries mobility decreases with increasing the temperature also with increasing the carriers concentration. We have observed that substituting As by Sb lead to increase the carries mobility of Ba{sub 2}Cd{sub 2}Sb{sub 3} along the whole temperature interval and the carries concentration range. It has been found that Ba{sub 2}Cd{sub 2}As{sub 3} exhibit higher carriers concentration, electronic electrical conductivity and Seebeck coefficient than that of Ba{sub 2}Cd{sub 2}Sb{sub 3} along the investigated temperature range. The highest value of Seebeck coefficient occurs at 300 K, which show good agreement with the experimental data. The power factor increases linearly with

  8. The Peptide PnPP-19, a Spider Toxin Derivative, Activates μ-Opioid Receptors and Modulates Calcium Channels

    Directory of Open Access Journals (Sweden)

    Ana C. N. Freitas

    2018-01-01

    Full Text Available The synthetic peptide PnPP-19 comprehends 19 amino acid residues and it represents part of the primary structure of the toxin δ-CNTX-Pn1c (PnTx2-6, isolated from the venom of the spider Phoneutria nigriventer. Behavioural tests suggest that PnPP-19 induces antinociception by activation of CB1, μ and δ opioid receptors. Since the peripheral and central antinociception induced by PnPP-19 involves opioid activation, the aim of this work was to identify whether this synthetic peptide could directly activate opioid receptors and investigate the subtype selectivity for μ-, δ- and/or κ-opioid receptors. Furthermore, we also studied the modulation of calcium influx driven by PnPP-19 in dorsal root ganglion neurons, and analyzed whether this modulation was opioid-mediated. PnPP-19 selectively activates μ-opioid receptors inducing indirectly inhibition of calcium channels and hereby impairing calcium influx in dorsal root ganglion (DRG neurons. Interestingly, notwithstanding the activation of opioid receptors, PnPP-19 does not induce β-arrestin2 recruitment. PnPP-19 is the first spider toxin derivative that, among opioid receptors, selectively activates μ-opioid receptors. The lack of β-arrestin2 recruitment highlights its potential for the design of new improved opioid agonists.

  9. Synthesis and characterization of p-n homojunction-containing zinc oxide nanowires.

    Science.gov (United States)

    Li, Guohua; Sundararajan, Abhishek; Mouti, Anas; Chang, Yao-Jen; Lupini, Andrew R; Pennycook, Stephen J; Strachan, Douglas R; Guiton, Beth S

    2013-03-21

    We illustrate a simple method to synthesize highly ordered ZnO axial p-n homojunction-containing nanowires using a low temperature method, and on a variety of substrates. X-ray diffraction, scanning transmission electron microscopy, scanning electron microscopy, and Raman spectroscopy are used to reveal high quality single-crystalline wires with a [001] growth direction. The study of electrical transport through a single nanowire based device and cathodoluminescence via scanning transmission electron microscopy demonstrates that an axial p-n junction exists within each ZnO nanowire. This represents the first low temperature synthesis of axial p-n homojunction-containing ZnO nanowires with uniform and controllable diameters.

  10. The ZnO p-n homojunctions modulated by ZnMgO barriers

    Directory of Open Access Journals (Sweden)

    Jing-Jing Yang

    2015-04-01

    Full Text Available In this paper, we fabricated the ultrathin ZnO p-n homojunctions, which modulated by ZnMgO asymmetrical double barriers (ADB. The ADB p-n homojunctions displays step-like curve in the absorption spectrums, this is the first time that quantum confinement effect has been observed in the absorption spectrums at room temperature (RT. The Hall-effect data confirm there is 2-dimensional electron gas in the interface of the ZnMgO ADB p-n junctions. The quantum confinement effect enhances the hall-mobility μ to 103 cm2V −1s−1 based on the polarity of the films. There was no rectification property in the ZnO homojunctions with thickness of 250nm, however, when the ADB was added in the n-type layer of the homojunctions, it displays a typical Zener diode rectification property in the I-V curve.

  11. Nanoscale imaging of the photoresponse in PN junctions of InGaAs infrared detector

    Science.gov (United States)

    Xia, Hui; Li, Tian-Xin; Tang, Heng-Jing; Zhu, Liang; Li, Xue; Gong, Hai-Mei; Lu, Wei

    2016-02-01

    Electronic layout, such as distributions of charge carriers and electric field, in PN junction is determinant for the photovoltaic devices to realize their functionality. Considerable efforts have been dedicated to the carrier profiling of this specific region with Scanning Probe Microscope, yet reliable analysis was impeded by the difficulty in resolving carriers with high mobility and the unclear surface effect, particularly on compound semiconductors. Here we realize nanometer Scanning Capacitance Microscopic study on the cross-section of InGaAs/InP photodetctors with the featured dC/dV layout of PN junction unveiled for the first time. It enables us to probe the photo-excited minority carriers in junction region and diagnose the performance deficiency of the diode devices. This work provides an illuminating insight into the PN junction for assessing its basic capability of harvesting photo-carriers as well as blocking leakage current in nanoscopic scale.

  12. A high performance charge plasma PN-Schottky collector transistor on silicon-on-insulator

    Science.gov (United States)

    Loan, Sajad A.; Bashir, Faisal; Rafat, M.; Alamoud, Abdul Rehman M.; Abbasi, Shuja A.

    2014-09-01

    In this paper, we propose a new high performance PN-Schottky collector (PN-SC) lateral bipolar junction transistor (BJT) on silicon-on-insulator (SOI). The proposed device addresses the problem of poor speed of conventional lateral PNP-BJT device by using a Schottky collector. Further, it does not use the conventional ways of ion implantation/diffusion to realize n and p type doped region. However, it uses metal electrodes of different work functions to create n and p type charge plasma in an undoped silicon film. The simulation study of the proposed lateral PN-SC bipolar charge plasma transistor on SOI (PN-SC-BCPT) device has shown a significant improvement in current gain (β), cutoff frequency (f T) and switching performance in comparison to conventional PNP-BJT and PNP-bipolar charge plasma transistor (PNP-BCPT) devices. A significantly high β is obtained in the proposed PN-SC-BCPT (˜2100) in comparison to PNP-BCPT (˜1450) and the conventional BJT (˜9) devices, respectively. It has been observed that there is 89.56% and 153.5% increase in f T for the proposed PN-SC-BCPT device (2.18 GHz) in comparison to conventional PNP-BJT (1.15 GHz) and PNP-BCPT (0.86 GHz) devices, respectively. Further, reductions of 24.6% and 15.4% in switching ON-delay and 66% and 30.76% in switching OFF-delay have been achieved in the proposed device based inverters in comparison to PNP-BCPT and the conventional BJT devices based inverters, respectively. Furthermore, the proposed device does not face doping related issues and the requirement of high temperature processing is absent.

  13. Catalytic growth of vertically aligned SnS/SnS2 p-n heterojunctions

    Science.gov (United States)

    Degrauw, Aaron; Armstrong, Rebekka; Rahman, Ajara A.; Ogle, Jonathan; Whittaker-Brooks, Luisa

    2017-09-01

    Nanowire arrays of SnS/SnS2 p-n heterojunctions are grown on transparent indium tin oxide (ITO) coated-glass and Si/SiO2 substrates via chemical vapor transport (CVT). The nanowire arrays are comprised of individual SnS/SnS2 heterostructures that are highly oriented with their lengths and morphologies controlled by the CVT conditions (i.e. reaction temperature, flow rate, and reaction time). The growth and optoelectronic characterization of these well-defined SnS/SnS2 p-n heterostructures pave the way for the fabrication of highly efficient solar cell devices.

  14. Impact of temperature and nitrogen composition on the growth of GaAsPN alloys

    Science.gov (United States)

    Yamane, Keisuke; Mugikura, Shun; Tanaka, Shunsuke; Goto, Masaya; Sekiguchi, Hiroto; Okada, Hiroshi; Wakahara, Akihiro

    2018-03-01

    This paper presents the impact of temperature and nitrogen-composition on the growth mode and crystallinity of GaAsPN alloys. Reflection high-energy electron diffraction results combined with transmission electron microscopy analysis revealed that maintaining two-dimensional (2-D) growth required higher temperatures when nitrogen composition increased. Outside the 2-D growth windows, stacking faults and micro-twins were preferentially formed at {1 1 1} B planes rather than at the {1 1 1} A planes and anomalous growth was observed. The photoluminescence spectra of GaAsPN layers implies that the higher temperature growth is effective for reducing the nitrogen-related point defects.

  15. Two southern planetary nebulae ESO 263-PN 02 and SchuWe-3

    CERN Document Server

    West, R M

    1980-01-01

    Spectroscopic observations show that two newly discovered southern objects, ESO 263-PN 02 and SchuWe-3, are planetary nebulae. ESO 263-PN 02 has a high excitation at the center and the 15/sup m/ central star is of very early type. SchuWe-3 has ring-shape, is reddened (A /sub V/ approximately 1/sup m/) and has a low excitation and electron density in the ring. The distance is estimated between 0.6 and 5 kpc, but is probably closer to the lower value. The measured velocities are +33+or-20 and -194+or-15 km s/sup -1/, respectively. (10 refs).

  16. pn karimi'*, sm maru', jm bururia', kam kuria' and pa odhiamboz

    African Journals Online (AJOL)

    Prevalence and Antimicrobial Susceptibility of Staphylococcus aureus at the Kenyatta National. Hospital, Nairobi. P.N. KARIMI'*, S.M. ... choose suitable drugs in the management of wounds for hospitalized patients. Key words: Prevalence ... poisoning, toxic shock syndrome and scalded skin syndrome [2]. Nasal carriage of ...

  17. Gate-tunable carbon nanotube–MoS2 heterojunction p-n diode

    Science.gov (United States)

    Jariwala, Deep; Sangwan, Vinod K.; Wu, Chung-Chiang; Prabhumirashi, Pradyumna L.; Geier, Michael L.; Marks, Tobin J.; Lauhon, Lincoln J.; Hersam, Mark C.

    2013-01-01

    The p-n junction diode and field-effect transistor are the two most ubiquitous building blocks of modern electronics and optoelectronics. In recent years, the emergence of reduced dimensionality materials has suggested that these components can be scaled down to atomic thicknesses. Although high-performance field-effect devices have been achieved from monolayered materials and their heterostructures, a p-n heterojunction diode derived from ultrathin materials is notably absent and constrains the fabrication of complex electronic and optoelectronic circuits. Here we demonstrate a gate-tunable p-n heterojunction diode using semiconducting single-walled carbon nanotubes (SWCNTs) and single-layer molybdenum disulfide as p-type and n-type semiconductors, respectively. The vertical stacking of these two direct band gap semiconductors forms a heterojunction with electrical characteristics that can be tuned with an applied gate bias to achieve a wide range of charge transport behavior ranging from insulating to rectifying with forward-to-reverse bias current ratios exceeding 104. This heterojunction diode also responds strongly to optical irradiation with an external quantum efficiency of 25% and fast photoresponse <15 μs. Because SWCNTs have a diverse range of electrical properties as a function of chirality and an increasing number of atomically thin 2D nanomaterials are being isolated, the gate-tunable p-n heterojunction concept presented here should be widely generalizable to realize diverse ultrathin, high-performance electronics and optoelectronics. PMID:24145425

  18. Dynamic SPECT of the brain using a lipophilic technetium-99m complex, PnAO

    DEFF Research Database (Denmark)

    Holm, S; Andersen, A R; Vorstrup, S

    1985-01-01

    The lipophilic 99mTc-labeled oxime propylene amine oxime (PnAO) should, according to recent reports behave like 133Xe in the human brain. This study compares SPECT images of the two tracers in six subjects: four stroke cases, one transitory ischemic attack case and one normal subject. Technetium-......AO has a high yet incomplete brain extraction yielding a flow dominated initial distribution with limitations mentioned.......The lipophilic 99mTc-labeled oxime propylene amine oxime (PnAO) should, according to recent reports behave like 133Xe in the human brain. This study compares SPECT images of the two tracers in six subjects: four stroke cases, one transitory ischemic attack case and one normal subject. Technetium-99......m PnAO was injected i.v. as a bolus of 15 to 25 mCi. The distribution was followed over 10-sec intervals using a highly sensitive, rapidly rotating SPECT (Tomomatic 64) and compared to 133Xe flow maps. Upon arrival of the PnAO bolus to the brain, a high uptake was found in brain tissue with high...

  19. Enhanced spin Seebeck effect in a germanene p-n junction

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, Jun [College of New Energy, Bohai University, Jinzhou 121013 (China); Chi, Feng [School of Physical Science and Technology, Inner Mongolia University, Huhehaote 010023 (China); College of Engineering, Bohai University, Jinzhou 121013 (China); Guo, Yong [Department of Physics and State Key Laboratory of Low-Dimensional Quantum Physics, Tsinghua University, Beijing 100084 (China); Collaborative Innovation of Quantum Matter, Beijing (China)

    2014-12-28

    Spin Seebeck effect in a germanene p-n junction is studied by using the nonequilibrium Green's function method combined with the tight-binding Hamiltonian. We find that the thermal bias ΔT can generate spin thermopower when a local exchange field is applied on one edge of the germanene nano-ribbon. The magnitude of the spin thermopower can be modulated by the potential drop across the two terminals of the p-n junction. When the value of the potential drop is smaller than the spin-orbit interaction strength, the spin thermopower is enhanced by two orders of magnitude larger as compared to the case of zero p-n voltage. Optimal temperature corresponding to maximum spin thermopower is insensitive to the potential drop. In the p-n region, maximum spin thermopower can be obtained at relatively higher temperatures. When the value of the potential drop is larger than that of the spin-orbit interaction, however, the spin Seebeck effect decays rapidly with increasing potential drop or temperature. By optimizing the structure parameters, the magnitude of the spin thermopower can be remarkably enhanced due to the coexistence of the exchange field and the potential drop.

  20. Gamma rays from the 31P(n, γ)32P reaction

    NARCIS (Netherlands)

    Middelkoop, G. van

    1967-01-01

    The 31P(n, γ)32P reaction is studied with a 5 cm3 Ge(Li) counter. Altogether, 54 γ-rays are detected with experimental energy errors between 0.4 and 3.0 keV. The Q-value of the reaction is determined as Q = 7936.8±0.8 keV.

  1. Photocurrent generation in lateral graphene p-n junction created by electron-beam irradiation

    KAUST Repository

    Yu, Xuechao

    2015-07-08

    Graphene has been considered as an attractive material for optoelectronic applications such as photodetectors owing to its extraordinary properties, e.g. broadband absorption and ultrahigh mobility. However, challenges still remain in fundamental and practical aspects of the conventional graphene photodetectors which normally rely on the photoconductive mode of operation which has the drawback of e.g. high dark current. Here, we demonstrated the photovoltaic mode operation in graphene p-n junctions fabricated by a simple but effective electron irradiation method that induces n-type doping in intrinsic p-type graphene. The physical mechanism of the junction formation is owing to the substrate gating effect caused by electron irradiation. Photoresponse was obtained for this type of photodetector because the photoexcited electron-hole pairs can be separated in the graphene p-n junction by the built-in potential. The fabricated graphene p-n junction photodetectors exhibit a high detectivity up to ~3 × 1010 Jones (cm Hz1/2 W−1) at room temperature, which is on a par with that of the traditional III–V photodetectors. The demonstrated novel and simple scheme for obtaining graphene p-n junctions can be used for other optoelectronic devices such as solar cells and be applied to other two dimensional materials based devices.

  2. THE REGULATION AND TREND OF PARTICIPATORY NOTES (PN) IN INDIA-- A Review

    OpenAIRE

    Dr. D. S. Selvakumar*

    2016-01-01

    India allowed Foreign Institutional Investors (FIIs) to buy stocks listed on Indian exchanges. However, all investors, whether institutions or individuals, were required to register themselves with the capital markets regulator, SEBI. To get around these restrictions, FIIs started to issue so-called participatory notes. This paper attempts to review the problems, regulations, growth and the recent trends in PN investments.

  3. Estimating p-n Diode Bulk Parameters, Bandgap Energy and Absolute Zero by a Simple Experiment

    Science.gov (United States)

    Ocaya, R. O.; Dejene, F. B.

    2007-01-01

    This paper presents a straightforward but interesting experimental method for p-n diode characterization. The method differs substantially from many approaches in diode characterization by offering much tighter control over the temperature and current variables. The method allows the determination of important diode constants such as temperature…

  4. The 2H(e, e' p)n reaction at large energy transfers

    NARCIS (Netherlands)

    Willering, Hendrik Willem

    2003-01-01

    At the ELSA accelerator facillity in Bonn, Germany, we have measured the deutron "breakup" reaction 2H(e,e' p)n at four-momentum transfers around Q2 = -0 .20(GeV/c)2 with an electron beam energy of E0 = 1.6 GeV. The cross section has been determined for energy transfers extending from the

  5. Cycle multiplicity of total graph of Cn, Pn, and K1,n | Ali ...

    African Journals Online (AJOL)

    Cycle multiplicity of a graph G is the maximum number of edge disjoint cycles in G. In this paper, we find the cycle multiplicity of total graph of cycles Cn, paths Pn, and star graph K1,n respectively. Keywords: cycle multiplicity, total graph, cycle, path, star graph.

  6. Total number of planetary nebulae in different galaxies and the PN distance scale.

    Science.gov (United States)

    Peimbert, M.

    1990-12-01

    RESUMEN A partir de una muestra de quince galaxias se encuentra que la tasa de natalidad de nebulosas planetarias por unidad de luminosidad, , disminuye al aumentar la luminosidad y al aumentar (B - V)0. Se discuten posibles explicaciones para estos resultados. Se estima el valor de para la Galaxia y a partir de el se encuentra que el numero total de nebulosas planetarias en nuestra galaxia con R mortalidad estelar por unidad de luminosidad y la tasa de natalidad de enanas blancas favorecen escalas de distancias largas para nebulosas planetarias, como la de Cudworth (1974) y la de Mallik y Peimbert (1988). ABSTRACT From a sample of fifteen galaxies it is found that the birth rate of PN per unit luminosity, , decreases with increasing luminosity and with increasing (B - V)0 possible reasons for these relationships are discussed. The value for the Galaxy is estimated and, from it, a total number of PN of 7200 # 1800 wid R < 0.64 pc is obtained. The galactic value implies that most of the intermediate mass stars go through the PN stage. The galactic value, the stellar death rate per unit luminosity and the white dwarf birth rate are in favor of long distance scales to PN like those of Cudworth (1974) and Mallik and (1988). Key wonis: NEBULAE.PLANETARY - STARS-EVOLUTION - STARS-SThLIAR STA. S

  7. Photocurrent spectroscopy of exciton and free particle optical transitions in suspended carbon nanotube pn-junctions

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Shun-Wen [Department of Physics and Astronomy, University of Southern California, Los Angeles, California 90089 (United States); Theiss, Jesse; Hazra, Jubin; Aykol, Mehmet; Kapadia, Rehan [Department of Electrical Engineering, University of Southern California, Los Angeles, California 90089 (United States); Cronin, Stephen B. [Department of Physics and Astronomy, University of Southern California, Los Angeles, California 90089 (United States); Department of Electrical Engineering, University of Southern California, Los Angeles, California 90089 (United States); Department of Chemistry, University of Southern California, Los Angeles, California 90089 (United States)

    2015-08-03

    We study photocurrent generation in individual, suspended carbon nanotube pn-junction diodes formed by electrostatic doping using two gate electrodes. Photocurrent spectra collected under various electrostatic doping concentrations reveal distinctive behaviors for free particle optical transitions and excitonic transitions. In particular, the photocurrent generated by excitonic transitions exhibits a strong gate doping dependence, while that of the free particle transitions is gate independent. Here, the built-in potential of the pn-junction is required to separate the strongly bound electron-hole pairs of the excitons, while free particle excitations do not require this field-assisted charge separation. We observe a sharp, well defined E{sub 11} free particle interband transition in contrast with previous photocurrent studies. Several steps are taken to ensure that the active charge separating region of these pn-junctions is suspended off the substrate in a suspended region that is substantially longer than the exciton diffusion length and, therefore, the photocurrent does not originate from a Schottky junction. We present a detailed model of the built-in fields in these pn-junctions, which, together with phonon-assistant exciton dissociation, predicts photocurrents on the same order of those observed experimentally.

  8. Electrostatics of lateral p-n junctions in atomically thin materials

    Science.gov (United States)

    Nipane, Ankur; Jayanti, Sirisha; Borah, Abhinandan; Teherani, James T.

    2017-11-01

    The lack of analytical expressions for the electrostatics of asymmetrically doped 2D lateral junctions complicates the design and analysis of devices based on atomically thin materials. In this work, we provide analytical expressions for the electric field, electrostatic potential, and depletion width across 2D lateral p-n junctions with arbitrary, but spatially uniform doping configurations. We also extend these expressions for use in lateral 3D metal-2D semiconductor junctions and lateral 2D heterojunctions. The results show a significantly larger depletion width (˜2 to 20×) for our 2D method compared to a conventional 3D approach due to the presence of a large out-of-plane electric field. For asymmetrically doped p-n junctions, the 2D depletion width shows a logarithmic dependence on the doping density of the highly doped side, in sharp contrast with conventional electrostatics for 3D junctions. Further, we show that 2D lateral depletion widths can be significantly modulated by changing the surrounding dielectric environment and, hence, can be tuned to realize optimum device structures. Finally, we show that even though the long depletion tails in 2D lateral p-n junctions carry a significant amount of total net charge, they do not significantly affect the electric field and electrostatic potential profiles, supporting the validity of the depletion approximation in analytical modeling of 2D lateral p-n junctions.

  9. Spin-dependent Seebeck effects in a graphene superlattice p-n junction with different shapes

    Science.gov (United States)

    Zhou, Benhu; Zhou, Benliang; Yao, Yagang; Zhou, Guanghui; Hu, Ming

    2017-10-01

    We theoretically calculate the spin-dependent transmission probability and spin Seebeck coefficient for a zigzag-edge graphene nanoribbon p-n junction with periodically attached stubs under a perpendicular magnetic field and a ferromagnetic insulator. By using the nonequilibrium Green’s function method combining with the tight-binding Hamiltonian, it is demonstrated that the spin-dependent transmission probability and spin Seebeck coefficient for two types of superlattices can be modulated by the potential drop, the magnetization strength, the number of periods of the superlattice, the strength of the perpendicular magnetic field, and the Anderson disorder strength. Interestingly, a metal to semiconductor transition occurs as the number of the superlattice for a crossed superlattice p-n junction increases, and its spin Seebeck coefficient is much larger than that for the T-shaped one around the zero Fermi energy. Furthermore, the spin Seebeck coefficient for crossed systems can be much pronounced and their maximum absolute value can reach 528 μV K-1 by choosing optimized parameters. Besides, the spin Seebeck coefficient for crossed p-n junction is strongly enhanced around the zero Fermi energy for a weak magnetic field. Our results provide theoretical references for modulating the thermoelectric properties of a graphene superlattice p-n junction by tuning its geometric structure and physical parameters.

  10. Hydrogenation of esters catalyzed by ruthenium PN3-Pincer complexes containing an aminophosphine arm

    KAUST Repository

    Chen, Tao

    2014-08-11

    Hydrogenation of esters under mild conditions was achieved using air-stable ruthenium PN3-pincer complexes containing an aminophosphine arm. High efficiency was achieved even in the presence of water. DFT studies suggest a bimolecular proton shuttle mechanism which allows H2 to be activated by the relatively stable catalyst with a reasonably low transition state barrier. © 2014 American Chemical Society.

  11. Cathodoluminescence analysis of cleaved facets of a ZnSe p-n junction

    Science.gov (United States)

    Wang, C.; As, D. J.; Buda, B.; Lübbers, M.; Schikora, D.; Mimkes, J.; Lischka, K.

    2000-04-01

    ZnSe diodes grown on (100) GaAs substrates by molecular beam epitaxy were investigated using cathodoluminesence (CL) measurements at sample temperatures between 50 and 300 K. The CL line scans at different photon energies were performed on cleaved p-n junctions at 50 and 300 K, respectively. Taking into account surface recombination, carrier generation volume, carrier diffusion and internal built-in electric field and related carrier drift, the CL measurements from cleaved p-n junctions could be qualitatively explained. The charge depletion layer has a strong influence on the CL measurements. The calculated charge depletion width is in good agreement with CL measurements. The experimental data from the spatially resolved CL on the cleaved ZnSe diodes revealed important information of the carrier dynamics and recombination processes in these devices.

  12. Fabrication and electrical properties of axial and radial GaAs nanowire pn junction diode arrays

    Science.gov (United States)

    Li, Jun-Shuai; Zhang, Xia; Yan, Xin; Chen, Xiong; Li, Liang; Cui, Jian-Gong; Huang, Yong-Qing; Ren, Xiao-Min

    2014-12-01

    We report on the fabrications and characterizations of axial and radial GaAs nanowire pn junction diode arrays. The nanowires are grown on n-doped GaAs (111)B substrates using the Au-catalyzed vapor—liquid—solid mechanism by metal—organic chemical vapor deposition (MOCVD). Diethyl—zinc and silane are used as p- and n-type dopant precursors, respectively. Both the axial and radial diodes exhibit diode-like J—V characteristics and have similar performances under forward bias. Under backward bias, the axial diode has a large leakage current, which is attributed to the bending of the pn junction interface induced by two doping mechanisms in Au-catalyzed nanowires. The low leakage current and high rectification ratio make the radial diode more promising in electrical and optoelectronic devices.

  13. Equilibration of quantum hall edge states and its conductance fluctuations in graphene p-n junctions

    Science.gov (United States)

    Kumar, Chandan; Kuiri, Manabendra; Das, Anindya

    2018-02-01

    We report an observation of conductance fluctuations (CFs) in the bipolar regime of quantum hall (QH) plateaus in graphene (p-n-p/n-p-n) devices. The CFs in the bipolar regime are shown to decrease with increasing bias and temperature. At high temperature (above 7 K) the CFs vanishes completely and the flat quantized plateaus are recovered in the bipolar regime. The values of QH plateaus are in theoretical agreement based on full equilibration of chiral channels at the p-n junction. The amplitude of CFs for different filling factors follows a trend predicted by the random matrix theory. Although, there are mismatch in the values of CFs between the experiment and theory but at higher filling factors the experimental values become closer to the theoretical prediction. The suppression of CFs and its dependence has been understood in terms of time dependent disorders present at the p-n junctions.

  14. Draft User Functionalities and Interfaces of PN Services (Low-Fi Prototyping)

    DEFF Research Database (Denmark)

    Karamolegkos, P.; Larsen, J. E.; Larsen, Lars Bo

    2006-01-01

    Internal report of WP1 Task 4 activities from January 2006 to August 2006. This report describes the draft user functionalities and coming user interfaces for PN services. It is a working document to be handed over to WP1 Task1 and Task3 for guidelines on specification. State of the art usability...... and user experience, conceptual design work on the two pilot services, MAGNET.CARE and Nomadic@Work, is described.......Internal report of WP1 Task 4 activities from January 2006 to August 2006. This report describes the draft user functionalities and coming user interfaces for PN services. It is a working document to be handed over to WP1 Task1 and Task3 for guidelines on specification. State of the art usability...

  15. Modeling pN2 through Geological Time: Implications for Planetary Climates and Atmospheric Biosignatures

    Science.gov (United States)

    Stüeken, E. E.; Kipp, M. A.; Koehler, M. C.; Schwieterman, E. W.; Johnson, B.; Buick, R.

    2016-12-01

    Nitrogen is a major nutrient for all life on Earth and could plausibly play a similar role in extraterrestrial biospheres. The major reservoir of nitrogen at Earth's surface is atmospheric N2, but recent studies have proposed that the size of this reservoir may have fluctuated significantly over the course of Earth's history with particularly low levels in the Neoarchean - presumably as a result of biological activity. We used a biogeochemical box model to test which conditions are necessary to cause large swings in atmospheric N2 pressure. Parameters for our model are constrained by observations of modern Earth and reconstructions of biomass burial and oxidative weathering in deep time. A 1-D climate model was used to model potential effects on atmospheric climate. In a second set of tests, we perturbed our box model to investigate which parameters have the greatest impact on the evolution of atmospheric pN2 and consider possible implications for nitrogen cycling on other planets. Our results suggest that (a) a high rate of biomass burial would have been needed in the Archean to draw down atmospheric pN2 to less than half modern levels, (b) the resulting effect on temperature could probably have been compensated by increasing solar luminosity and a mild increase in pCO2, and (c) atmospheric oxygenation could have initiated a stepwise pN2 rebound through oxidative weathering. In general, life appears to be necessary for significant atmospheric pN2 swings on Earth-like planets. Our results further support the idea that an exoplanetary atmosphere rich in both N2 and O2 is a signature of an oxygen-producing biosphere.

  16. Photovoltaic characteristics of diffused P/+N bulk GaAs solar cells

    Science.gov (United States)

    Borrego, J. M.; Keeney, R. P.; Bhat, I. B.; Bhat, K. N.; Sundaram, L. G.; Ghandhi, S. K.

    1982-01-01

    The photovoltaic characteristics of P(+)N junction solar cells fabricated on bulk GaAs by an open tube diffusion technique are described in this paper.Spectral response measurements were analyzed in detail and compared to a computer simulation in order to determine important material parameters. It is projected that proper optimization of the cell parameters can increase the efficiency of the cells from 12.2 percent to close to 20 percent.

  17. Pn tomography of South China Sea, Taiwan Island, Philippine archipelago, and adjacent regions

    Science.gov (United States)

    Li, Xibing; Song, Xiaodong; Li, Jiangtao

    2017-02-01

    The South China Sea (SCS) and its surrounding areas are geologically highly heterogeneous from the interactions of multiple plates in Southeast Asia (Eurasian plate, Indian-Australian plate, Philippine Sea plate, and Pacific plate). To understand the tectonics at depth, here we combined bulletin and handpicked data to conduct Pn tomography of the region. The results show distinct features that are correlated with the complex geology at surface, suggesting a lithosphere-scale tectonics of the region. Low Pn velocities are found along a belt of the western Pacific transpressional system from the Okinawa Trough and eastern East China Sea, across central and eastern Taiwan orogeny, to the island arcs of the Luzon Strait and the entire Philippine Islands, as well as under the Palawan Island and part of the continental margin north of the Pearl River Basin. High velocities are found under Ryukyu subduction zone, part of the Philippine subduction zone, part of the Eurasian subduction beneath the southwestern Taiwan, and the continent-ocean boundary between the south China and the SCS basin. The Taiwan Strait, the Mainland SE coast, and the main SCS basin sea are relatively uniform with average Pn values. Crustal thicknesses show large variations in the study region but also coherency with tectonic elements. The Pn pattern in Taiwan shows linear trends of surface geology and suggests strongly lithosphere-scale deformation of the young Taiwan orogenic belt marked by the deformation boundary under the Western Foothill and the Western Coastal Plain at depth, and the crustal thickness shows a complex pattern from the transpressional collision. Our observations are consistent with rifting and extension in the northern margin of the SCS but are not consistent with mantle upwelling as a mechanism for the opening and the subsequent closing of the SCS. The Philippine island arc is affected by volcanisms from both the Asian and Philippine Sea subductions in the south but mainly from

  18. Integrated CLOS and PN Guidance for Increased Effectiveness of Surface to Air Missiles

    OpenAIRE

    Binte Fatima Tuz ZAHRA; Syed Tauqeer ul Islam RIZVI; Syed Irtiza Ali SHAH

    2017-01-01

    In this paper, a novel approach has been presented to integrate command to line-of-sight (CLOS) guidance and proportional navigation (PN) guidance in order to reduce miss distance and to increase the effectiveness of surface to air missiles. Initially a comparison of command to line-of-sight guidance and proportional navigation has been presented. Miss distance, variation of angle-of-attack, normal and lateral accelerations and error of missile flight path from direct line-of-sight have been ...

  19. Oscillating Magnetoresistance in Graphene p-n Junctions at Intermediate Magnetic Fields

    Science.gov (United States)

    Overweg, Hiske; Eggimann, Hannah; Liu, Ming-Hao; Varlet, Anastasia; Eich, Marius; Simonet, Pauline; Lee, Yongjin; Watanabe, Kenji; Taniguchi, Takashi; Richter, Klaus; Fal'ko, Vladimir I.; Ensslin, Klaus; Ihn, Thomas

    2017-05-01

    We report on the observation of magnetoresistance oscillations in graphene p-n junctions. The oscillations have been observed for six samples, consisting of single-layer and bilayer graphene, and persist up to temperatures of 30 K, where standard Shubnikov-de Haas oscillations are no longer discernible. The oscillatory magnetoresistance can be reproduced by tight-binding simulations. We attribute this phenomenon to the modulated densities of states in the n- and p- regions.

  20. High breakdown single-crystal GaN p-n diodes by molecular beam epitaxy

    Science.gov (United States)

    Qi, Meng; Nomoto, Kazuki; Zhu, Mingda; Hu, Zongyang; Zhao, Yuning; Protasenko, Vladimir; Song, Bo; Yan, Xiaodong; Li, Guowang; Verma, Jai; Bader, Samuel; Fay, Patrick; Xing, Huili Grace; Jena, Debdeep

    2015-12-01

    Molecular beam epitaxy grown GaN p-n vertical diodes are demonstrated on single-crystal GaN substrates. A low leakage current GaN. Single-crystal GaN substrates with very low dislocation densities enable the low leakage current and the high breakdown field in the diodes, showing significant potential for MBE growth to attain near-intrinsic performance when the density of dislocations is low.

  1. Modeling pN2 through Geological Time: Implications for Planetary Climates and Atmospheric Biosignatures.

    Science.gov (United States)

    Stüeken, E E; Kipp, M A; Koehler, M C; Schwieterman, E W; Johnson, B; Buick, R

    2016-12-01

    Nitrogen is a major nutrient for all life on Earth and could plausibly play a similar role in extraterrestrial biospheres. The major reservoir of nitrogen at Earth's surface is atmospheric N2, but recent studies have proposed that the size of this reservoir may have fluctuated significantly over the course of Earth's history with particularly low levels in the Neoarchean-presumably as a result of biological activity. We used a biogeochemical box model to test which conditions are necessary to cause large swings in atmospheric N2 pressure. Parameters for our model are constrained by observations of modern Earth and reconstructions of biomass burial and oxidative weathering in deep time. A 1-D climate model was used to model potential effects on atmospheric climate. In a second set of tests, we perturbed our box model to investigate which parameters have the greatest impact on the evolution of atmospheric pN2 and consider possible implications for nitrogen cycling on other planets. Our results suggest that (a) a high rate of biomass burial would have been needed in the Archean to draw down atmospheric pN2 to less than half modern levels, (b) the resulting effect on temperature could probably have been compensated by increasing solar luminosity and a mild increase in pCO2, and (c) atmospheric oxygenation could have initiated a stepwise pN2 rebound through oxidative weathering. In general, life appears to be necessary for significant atmospheric pN2 swings on Earth-like planets. Our results further support the idea that an exoplanetary atmosphere rich in both N2 and O2 is a signature of an oxygen-producing biosphere. Key Words: Biosignatures-Early Earth-Planetary atmospheres. Astrobiology 16, 949-963.

  2. P-N junctions dynamics in graphene channel induced by ferroelectric domains motion

    OpenAIRE

    Kurchak, Anatolii I.; Eliseev, Eugene A.; Kalinin, Sergei V.; Strikha, Maksym V.; Morozovska, Anna N.

    2017-01-01

    The p-n junctions dynamics in graphene channel induced by stripe domains nucleation, motion and reversal in a ferroelectric substrate is explored using self-consistent approach based on Landau-Ginzburg-Devonshire phenomenology combined with classical electrostatics. We revealed the extrinsic size effect in the dependence of the graphene channel conductivity on its length. For the case of perfect electric contact between the ferroelectric and graphene, relatively low gate voltages are required...

  3. Nanoscale imaging of the photoresponse in PN junctions of InGaAs infrared detector

    OpenAIRE

    Hui Xia; Tian-Xin Li; Heng-Jing Tang; Liang Zhu; Xue Li; Hai-Mei Gong; Wei Lu

    2016-01-01

    Electronic layout, such as distributions of charge carriers and electric field, in PN junction is determinant for the photovoltaic devices to realize their functionality. Considerable efforts have been dedicated to the carrier profiling of this specific region with Scanning Probe Microscope, yet reliable analysis was impeded by the difficulty in resolving carriers with high mobility and the unclear surface effect, particularly on compound semiconductors. Here we realize nanometer Scanning Cap...

  4. Array analysis of regional Pn and Pg wavefields from the Nevada Test Site

    Energy Technology Data Exchange (ETDEWEB)

    Leonard, M.A. (California Univ., Berkeley, CA (United States). Dept. of Geology and Geophysics Lawrence Berkeley Lab., CA (United States))

    1991-06-01

    Small-aperture high-frequency seismic arrays with dimensions of a few kilometers or less, can improve our ability to seismically monitor compliance with a low-yield Threshold Test Ban Treaty. This work studies the characteristics and effectiveness of array processing of the regional Pn and Pg wavefields generated by underground nuclear explosions at the Nevada Test Site. Waveform data from the explosion HARDIN (m{sub b} = 5.5) is recorded at a temporary 12-element, 3-component, 1.5 km-aperture array sited in an area of northern Nevada. The explosions VILLE (m{sub b} = 4.4) and SALUT (m{sub b} = 5.5) are recorded at two arrays sited in the Mojave desert, one a 96-element vertical-component 7 km-aperture array and the other a 155-element vertical-component 4 km-aperture array. Among the mean spectra for the m{sub b} = 5.5 events there are significant differences in low-frequency spectral amplitudes between array sites. The spectra become nearly identical beyond about 6 Hz. Spectral ratios are used to examine seismic source properties and the partitioning of energy between Pn and Pg. Frequency-wavenumber analysis at the 12-element array is used to obtain estimates of signal gain, phase velocity, and source azimuth. This analysis reveals frequency-dependent biases in velocity and azimuth of the coherent Pn and Pg arrivals. Signal correlation, the principal factor governing array performance, is examined in terms of spatial coherence estimates. The coherence is found to vary between the three sites. In all cases the coherence of Pn is greater than that for Pg. 81 refs., 92 figs., 5 tabs.

  5. Electrical rectification in axial in-situ doped Ge nanowire pn junctions

    Science.gov (United States)

    Le, Son T.; Dayeh, S.; Picraux, S. T.; Zaslavsky, A.

    2010-03-01

    We demonstrate the vapor-liquid-solid growth of and electrical rectification in axial in-situ doped pn junction Ge nanowires (NWs). In-situ doping of the NWs was accomplished by introducing dopant gases (diborane and phosphine) during growth, resulting in an axial pn junction. Contacts to the wires were defined using e-beam lithography, followed by Ni metallization. Four-point measurements of the fabricated devices at room temperature and at 77 K clearly show rectification with on/off current ratio of more than two orders of magnitude when the bias is applied across the NW pn junction. The ideality factor of the junction current points to a significant generation-recombination contribution. The Ohmic characteristics in the p and n regions outside the junction make it possible to estimate the doping levels. We also observed gate control of the NW junction current using the substrate as a back gate. Observed current modulation is in good agreement with the electrostatic depletion of the NWs as a function of diameter and doping.

  6. FSHR polymorphism p.N680S mediates different responses to FSH in vitro.

    Science.gov (United States)

    Casarini, Livio; Moriondo, Valeria; Marino, Marco; Adversi, Francesca; Capodanno, Francesco; Grisolia, Chiarina; La Marca, Antonio; La Sala, Giovanni Battista; Simoni, Manuela

    2014-08-05

    The single nucleotide polymorphism p.N680S of the follicle-stimulating hormone (FSH) receptor (FSHR) is a discrete marker of ovarian response but previous in vitro studies failed to demonstrate differences in the response to FSH between N and S carrier cells. Here we demonstrate that p.N680S mediates different kinetics of the response to FSH in vitro. Intracellular cAMP production is faster in p.N680S N than in S homozygous human granulosa cells (45 versus 90 min to achieve the plateau, respectively; Mann-Whitney's U-test; p < 0.005; n = 4). Reflecting the cAMP kinetics, phospho-ERK1/2 and -CREB activation, AREG and STARD1 gene expressions and progesterone production were qualitatively and quantitatively different in N versus S homozygous cells. Finally, the blockade of ERK pathway by U0126 abolishes the genotype-mediated different effects on gene expression and progesterone production (Mann-Whitney's U-test; p ≥ 0.005; n = 3). Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  7. Polarization-induced pn diodes in wide-band-gap nanowires with ultraviolet electroluminescence.

    Science.gov (United States)

    Carnevale, Santino D; Kent, Thomas F; Phillips, Patrick J; Mills, Michael J; Rajan, Siddharth; Myers, Roberto C

    2012-02-08

    Almost all electronic devices utilize a pn junction formed by random doping of donor and acceptor impurity atoms. We developed a fundamentally new type of pn junction not formed by impurity-doping, but rather by grading the composition of a semiconductor nanowire resulting in alternating p and n conducting regions due to polarization charge. By linearly grading AlGaN nanowires from 0% to 100% and back to 0% Al, we show the formation of a polarization-induced pn junction even in the absence of any impurity doping. Since electrons and holes are injected from AlN barriers into quantum disk active regions, graded nanowires allow deep ultraviolet LEDs across the AlGaN band-gap range with electroluminescence observed from 3.4 to 5 eV. Polarization-induced p-type conductivity in nanowires is shown to be possible even without supplemental acceptor doping, demonstrating the advantage of polarization engineering in nanowires compared with planar films and providing a strategy for improving conductivity in wide-band-gap semiconductors. As polarization charge is uniform within each unit cell, polarization-induced conductivity without impurity doping provides a solution to the problem of conductivity uniformity in nanowires and nanoelectronics and opens a new field of polarization engineering in nanostructures that may be applied to other polar semiconductors. © 2012 American Chemical Society

  8. PN Sequence Preestimator Scheme for DS-SS Signal Acquisition Using Block Sequence Estimation

    Directory of Open Access Journals (Sweden)

    Sang Kyu Park

    2005-03-01

    Full Text Available An m-sequence (PN sequence preestimator scheme for direct-sequence spread spectrum (DS-SS signal acquisition by using block sequence estimation (BSE is proposed and analyzed. The proposed scheme consists of an estimator and a verifier which work according to the PN sequence chip clock, and provides not only the enhanced chip estimates with a threshold decision logic and one-chip error correction among the first m received chips, but also the reliability check of the estimates with additional decision logic. The probabilities of the estimator and verifier operations are calculated. With these results, the detection, the false alarm, and the missing probabilities of the proposed scheme are derived. In addition, using a signal flow graph, the average acquisition time is calculated. The proposed scheme can be used as a preestimator and easily implemented by changing the internal signal path of a generally used digital matched filter (DMF correlator or any other correlator that has a lot of sampling data memories for sampled PN sequence. The numerical results show rapid acquisition performance in a relatively good CNR.

  9. Growth and electrical rectification in axial in-situ doped p-n junction germanium nanowires

    Energy Technology Data Exchange (ETDEWEB)

    Picraux, Samuel T [Los Alamos National Laboratory; Dayeh, Shadi [Los Alamos National Laboratory; Zaslavsky, Alexander [BROWN U; Le, Son T [BROWN U

    2009-01-01

    In this work, we demonstrate the vapor-liquid-solid (VLS) growth and electrical properties of axial in-situ doped p-n junction Ge nanowires (NWs). In-situ doping of the NWs was accomplished by introducing dopant gases (diborane and phosphine) together with GeH{sub 4} in the growth process. By changing dopant sources during growth, a p-n junction can be realized along the axis of the NWs. Metal contacts to the wires were defined using e-beam lithography patterning, followed by 100 nm Ni sputter deposition and lift-off. Four-point measurements of the fabricated devices at room temperature and at 77 K clearly show rectification with on/off current ratio up to two orders of magnitude when the bias is applied across the p-n junction. The ideality factor of the junction current points to a significant generation-recombination contribution. The Ohmic characteristics in the p and n regions outside the junction make it possible to estimate the doping levels. We also observed backgate control of the NW junction current.

  10. The influence of replacing the pnicogens As by Sb on the optical properties of the Zintl phases Ba{sub 2}Cd{sub 2}Pn{sub 3} (Pn = As and Sb)

    Energy Technology Data Exchange (ETDEWEB)

    Reshak, A.H., E-mail: maalidph@yahoo.co.uk [New Technologies – Research Centre, University of West Bohemia, Univerzitni 8, 306 14 Pilsen (Czech Republic); Center of Excellence Geopolymer and Green Technology, School of Material Engineering, University Malaysia Perlis, 01007 Kangar, Perlis (Malaysia)

    2015-11-05

    We explored the influence of changing the pnicogens by substituting As by Sb on the optical properties of Ba{sub 2}Cd{sub 2}Pn{sub 3} (Pn = As and Sb). Calculation show that there exists subtle difference in the electronic structures when we substitute As by Sb, which lead to significant influence on the optical properties, taking into account the size and the electro-negativity differences between As and Sb atoms. The full potential method within the recently modified Becke-Johnson potential explore that the Ba{sub 2}Cd{sub 2}Pn{sub 3} (Pn = As and Sb) compounds are narrow band gap semiconductors of about 0.49 and 0.32 eV. The optical properties explore that these material have negative uniaxial anisotropy, negative birefringence and considerable anisotropy between the optical components in the polarization directions [100], [010] and [001] with respect to the crystal axis. Furthermore, the optical properties confirm that Ba{sub 2}Cd{sub 2}Sb{sub 3} possess a band gap which is smaller than that of Ba{sub 2}Cd{sub 2}As{sub 3}. The optical properties helps to get deep insight into the electronic structure. - Highlights: • The optical properties of Ba{sub 2}Cd{sub 2}Pn{sub 3} (Pn = As and Sb) were investigated. • The subtle difference in electronic structures influence the optical properties. • Ba{sub 2}Cd{sub 2}Pn{sub 3} (Pn = As and Sb) are narrow band gap semiconductors. • The investigated compounds exhibit negative uniaxial anisotropy and birefringence.

  11. Calculation of Initial Short-Circuit Currents in Medium Voltage Networks According to the Standard PN-EN 60909

    National Research Council Canada - National Science Library

    Krzysztof Księżyk; Tomasz Zdun

    2013-01-01

    Determining the short-circuit currents is usually conducted by network analyses. An important feature of this calculation is carried out according to the recommendations of the standard PN EN 60909...

  12. Efficient transfer hydrogenation reaction Catalyzed by a dearomatized PN 3P ruthenium pincer complex under base-free Conditions

    KAUST Repository

    He, Lipeng

    2012-03-01

    A dearomatized complex [RuH(PN 3P)(CO)] (PN 3PN, N′-bis(di-tert-butylphosphino)-2,6-diaminopyridine) (3) was prepared by reaction of the aromatic complex [RuH(Cl)(PN 3P)(CO)] (2) with t-BuOK in THF. Further treatment of 3 with formic acid led to the formation of a rearomatized complex (4). These new complexes were fully characterized and the molecular structure of complex 4 was further confirmed by X-ray crystallography. In complex 4, a distorted square-pyramidal geometry around the ruthenium center was observed, with the CO ligand trans to the pyridinic nitrogen atom and the hydride located in the apical position. The dearomatized complex 3 displays efficient catalytic activity for hydrogen transfer of ketones in isopropanol. © 2011 Elsevier B.V. All rights reserved.

  13. Comparison between variable and fixed dwell-time PN acquisition algorithms. [for synchronization in pseudonoise spread spectrum systems

    Science.gov (United States)

    Braun, W. R.

    1981-01-01

    Pseudo noise (PN) spread spectrum systems require a very accurate alignment between the PN code epochs at the transmitter and receiver. This synchronism is typically established through a two-step algorithm, including a coarse synchronization procedure and a fine synchronization procedure. A standard approach for the coarse synchronization is a sequential search over all code phases. The measurement of the power in the filtered signal is used to either accept or reject the code phase under test as the phase of the received PN code. This acquisition strategy, called a single dwell-time system, has been analyzed by Holmes and Chen (1977). A synopsis of the field of sequential analysis as it applies to the PN acquisition problem is provided. From this, the implementation of the variable dwell time algorithm as a sequential probability ratio test is developed. The performance of this algorithm is compared to the optimum detection algorithm and to the fixed dwell-time system.

  14. Acceptance Data Package: SXI Stepper Motor/Encoder. Aeroflex P/N 16187. A; Engineering Drawings and Associated Lists

    Science.gov (United States)

    1994-01-01

    Acceptance data package - engineering drawings and associated lists for fabrication, assembly and maintenance (cleaning, fluidized bed coating, bounding and staking) motor/encoded solar x-ray imager (SXI) (Aeroflex p/n 16187) were given.

  15. Peanut witches' broom (PnWB) phytoplasma-mediated leafy flower symptoms and abnormal vascular bundles development.

    Science.gov (United States)

    Liu, Chi-Te; Huang, Hsin-Mei; Hong, Syuan-Fei; Kuo-Huang, Ling-Long; Yang, Chiao-Yin; Lin, Yen-Yu; Lin, Chan-Pin; Lin, Shih-Shun

    2015-01-01

    The peanut witches' broom (PnWB) phytoplasma causes virescence symptoms such as phyllody (leafy flower) in infected peanuts. However, the obligate nature of phytoplasma limits the study of host-pathogen interactions, and the detailed anatomy of PnWB-infected plants has yet to be reported. Here, we demonstrate that 4',6'-diamidino-2-phenylindole (DAPI) staining can be used to track PnWB infection. The DAPI-stained phytoplasma cells were observed in phloem/internal phloem tissues, and changes in vascular bundle morphology, including increasing pith rays and thinner cell walls in the xylem, were found. We also discerned the cell types comprising PnWB in infected sieve tube members. These results suggest that the presence of PnWB in phloem tissue facilitates the transmission of phytoplasma via sap-feeding insect vectors. In addition, PnWB in sieve tube members and changes in vascular bundle morphology might strongly promote the ability of phytoplasmas to assimilate nutrients. These data will help further an understanding of the obligate life cycle and host-pathogen interactions of phytoplasma.

  16. Antiperovskite nitridophosphate oxide Ho{sub 3}[PN{sub 4}]O by high-pressure metathesis

    Energy Technology Data Exchange (ETDEWEB)

    Kloss, Simon D.; Weidmann, Niels; Schnick, Wolfgang [Department of Chemistry, University of Munich (LMU), Butenandtstrasse 5-13, 81377, Munich (Germany)

    2017-04-03

    Rare-earth nitridophosphates are a recently discovered class of materials, which are accessible by high-pressure metathesis. Antiperovskite-type Ho{sub 3}[PN{sub 4}]O was synthesized from HoF{sub 3}, LiPN{sub 2}, Li{sub 3}N, and Li{sub 2}O at 5 GPa and ca. 1025 C by this method and the multianvil technique. Ho{sub 3}[PN{sub 4}]O contains rarely observed isolated PN{sub 4} tetrahedra and can be derived by the hierarchical substitution of the ABX{sub 3} perovskite, in which Ho occupies the X positions, O occupies the B position, and the PN{sub 4} tetrahedra occupy the A position. The structure was refined on the basis of powder diffraction data [I4/mcm, a = 6.36112(3), c = 10.5571(1) Aa, Z = 4, R{sub wp} = 0.04, R{sub Bragg} = 0.01, χ{sup 2} = 2.275] starting from the structural model of isotypic Gd{sub 3}[SiN{sub 3}O]O. To characterize Ho{sub 3}[PN{sub 4}]O, elemental analyses were performed through energy-dispersive X-ray spectroscopy (EDX) and inductively coupled plasma optical emission spectroscopy (ICP-OES). Ho{sub 3}[PN{sub 4}]O is paramagnetic down to low temperatures with μ{sub eff} = 10.43(1) μ{sub B} and a Curie temperature (Θ) of 0.11(4) K. It shows the optical characteristics of Ho{sup 3+} ions and vibrations corresponding to isolated PN{sub 4} tetrahedra. On the basis of DFT calculations [generalized gradient approximation (GGA)], Ho{sub 3}[PN{sub 4}]O has an indirect band gap of 1.87 eV. We demonstrate the versatility of high-pressure metathesis by attaining the low end of the P/N atomic ratio κ = 1/4. This confirms the previous assumption that rare-earth nitridophosphates with κ = 1/2 to 1/4 are feasible by this method. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  17. What is the net effect of introducing vitrification for cryopreservation of surplus 2PN oocytes in an IVF program?

    Science.gov (United States)

    Golakov, Manja; Depenbusch, Marion; Schultze-Mosgau, Askan; Schoepper, Beate; Hajek, Jennifer; Neumann, Kay; Griesinger, Georg

    2018-02-01

    The aim of this study was to accurately describe outcome differences (cryo-survival, pregnancy rate and live birth rate, both per ET and cumulatively), between the vitrification method and slow-freezing method of surplus 2PN oocytes in an IVF program. In 2004, the freezing method for 2PN oocytes was changed from slow-cooling to vitrification. The data of 711 patients (timespan: 1/1999-7/2011; 410 vitrification and 301 slow-cooling events) undergoing a first IVF/ICSI cycles with freezing of 2PN oocytes were retrospectively analyzed. The outcome of one, the first, IVF cycle per patient was explored. The data were analyzed per freezing-thawing attempt as well as cumulatively per one complete IVF cycle, taking pregnancy occurrence after a fresh embryo transfer preceding the cryo-cycle(s) and other confounders (such as female age, elective vs. surplus 2PN cryopreservation) into account by means of exploratory regression analyses. In the vitrification and slow-cooling group, 756 and 376, respectively, attempts of thawing 2PN oocytes were recorded. Each attempt of thawing 2PN oocytes showed statistically significantly higher mean cryo-survival rates after vitrification (effect size approximately 30-40%, with vitrification cryo-survival consistently above 90% in all thawing attempts). Furthermore, the incidence of "zero survival" was lower after vitrification (0.5 vs. 7.3%, p IVF cycle (fresh and frozen transfers combined) with vitrification of 2PN oocytes is increased approximately 1.4-fold (OR of 1.405, 95% CI 0.968-2.038; p = 0.07); however, statistical significance was not achieved due to sample size. Female age and elective cryopreservation of all 2PN oocytes without a fresh transfer (e.g., hyperresponders) were found to be negatively and positively, respectively, associated with the chance of achieving a live birth. The introduction of vitrification has a measurable impact on the efficacy of an IVF program. However, this effect is not large despite the

  18. Doping GaP core-shell nanowire pn-junctions

    DEFF Research Database (Denmark)

    Yazdi, Sadegh; Berg, Alexander; Borgström, Magnus T.

    2015-01-01

    The doping process in GaP core-shell nanowire pn-junctions using different precursors is evaluated by mapping the nanowires' electrostatic potential distribution by means of off-axis electron holography. Three precursors, triethyltin (TESn), ditertiarybutylselenide, and silane are investigated......, ditertiarybutylselenide and silane for n-type doping of the shell and that the concentration of p-type dopants is higher in the region of core grown parasitically by vapor-solid mechanism due to unintentional carbon doping from trimethylgallium precursor....

  19. Model of human breathing reflected signal received by PN-UWB radar.

    Science.gov (United States)

    Mabrouk, Mohamed; Rajan, Sreeraman; Bolic, Miodrag; Batkin, Izmail; Dajani, Hilmi R; Groza, Voicu Z

    2014-01-01

    Human detection is an integral component of civilian and military rescue operations, military surveillance and combat operations. Human detection can be achieved through monitoring of vital signs. In this article, a mathematical model of human breathing reflected signal received in PN-UWB radar is proposed. Unlike earlier published works, both chest and abdomen movements are considered for modeling the radar return signal along with the contributions of fundamental breathing frequency and its harmonics. Analyses of recorded reflected signals from three subjects in different postures and at different ranges from the radar indicate that ratios of the amplitudes of the harmonics contain information about posture and posture change.

  20. Fabrication and characterization of 3D pn junction structure for radiation detection

    Science.gov (United States)

    Liu, Tingting; Liu, Tao; Li, Jinlong; Lin, Jilei; Chen, Xiaoming; Guo, Xinglong; Xin, Peisheng; Xu, Shaohui; Xue, Weijia; Wang, Lianwei

    2008-02-01

    In this report, p-type macroporous silicon has been prepared by anodization. A phosphorus diffusion step is employed for the formation of three dimensional pn junction structures on this macroporous silicon. I-V and C-V measurement were employed to characterize the electrical properties. The results were compared with numeric simulation with T-SUPREM4 and MEDICI. It has been demonstrated that three-dimensional structure can increase the effective junction area and the collective efficiency remarkably, and hence improve the performance of semiconductor radiation detector.

  1. Efficient p-n junction-based thermoelectric generator that can operate at extreme temperature conditions

    DEFF Research Database (Denmark)

    Chavez, Ruben; Angst, Sebastian; Hall, Joseph

    2017-01-01

    in part because electrical, thermal, and mechanical bonding contacts between the semiconductor materials and the metal electrodes in current designs are not capable of withstanding thermal-mechanical stress and alloying of the metal-semiconductor interface when exposed to the high temperatures occurring...... temperatures and oxidative atmosphere....... temperature induced failure. In our proof-of-principle demonstration a p-n junction device made from nanocrystalline silicon is at least comparable in its efficiency and power output to conventional devices of the same material and fabrication process, but with the advantage of sustaining high hot side...

  2. Uncooled CMOS terahertz imager using a metamaterial absorber and pn diode.

    Science.gov (United States)

    Escorcia, Ivonne; Grant, James; Gough, John; Cumming, David R S

    2016-07-15

    We demonstrate a low-cost uncooled terahertz (THz) imager fabricated in a standard 180 nm CMOS process. The imager is composed of a broadband THz metamaterial absorber coupled with a diode microbolometer sensor where the pn junction is used as a temperature sensitive device. The metamaterial absorber array is integrated in the top metallic layers of a six metal layer process allowing for complete monolithic integration of the metamaterial absorber and sensor. We demonstrate the capability of the detector for stand-off imaging applications by using it to form transmission and reflection images of a metallic object hidden in a manila envelope.

  3. A P-N Sequence Generator Using LFSR with Dual Edge Trigger Technique

    OpenAIRE

    Naghwal Nitin Kumar; Kumar Abhishek

    2016-01-01

    This paper represents the design and implementation of a low power 4-bit LFSR using Dual edge triggered flip flop. A linear feedback shift register (LFSR) is assembled by N number of flip flops connected in series and a combinational logic generally xor gate. An LFSR can generate random number sequence which acts as cipher in cryptography. A known text encrypted over long PN sequence, in order to improve security sequence made longer ie 128 bit; require long chain of flip flop leads to more p...

  4. Hybrid PN-SN Calculations with SAAF for the Multiscale Transport Capability in Rattlesnake

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Yaqi; Schunert, Sebastian; DeHart, Mark; Martineau, Richard

    2016-05-01

    Two interface conditions, the Lagrange multiplier method and the upwinding method, for hybrid \\pn-\\sn calculations is proposed for the self-adjoint angular flux (SAAF) formulation of the transport equation using the continuous finite element method (FEM) for spatial discretization. These interface conditions are implemented in Rattlesnake, the radiation transport application built on MOOSE, for the on-going multiscale transport simulation effort at INL. For smoothing the solution at the interface for the Lagrange multiplier method, a method based on \\sn Lagrange interpolation on the sphere is proposed. Numerical results indicate that the interface conditions give the expected convergence.

  5. Interlayer Exciton Optoelectronics in a 2D Heterostructure p-n Junction.

    Science.gov (United States)

    Ross, Jason S; Rivera, Pasqual; Schaibley, John; Lee-Wong, Eric; Yu, Hongyi; Taniguchi, Takashi; Watanabe, Kenji; Yan, Jiaqiang; Mandrus, David; Cobden, David; Yao, Wang; Xu, Xiaodong

    2017-02-08

    Semiconductor heterostructures are backbones for solid-state-based optoelectronic devices. Recent advances in assembly techniques for van der Waals heterostructures have enabled the band engineering of semiconductor heterojunctions for atomically thin optoelectronic devices. In two-dimensional heterostructures with type II band alignment, interlayer excitons, where Coulomb bound electrons and holes are confined to opposite layers, have shown promising properties for novel excitonic devices, including a large binding energy, micron-scale in-plane drift-diffusion, and a long population and valley polarization lifetime. Here, we demonstrate interlayer exciton optoelectronics based on electrostatically defined lateral p-n junctions in a MoSe 2 -WSe 2 heterobilayer. Applying a forward bias enables the first observation of electroluminescence from interlayer excitons. At zero bias, the p-n junction functions as a highly sensitive photodetector, where the wavelength-dependent photocurrent measurement allows the direct observation of resonant optical excitation of the interlayer exciton. The resulting photocurrent amplitude from the interlayer exciton is about 200 times smaller than the resonant excitation of intralayer exciton. This implies that the interlayer exciton oscillator strength is 2 orders of magnitude smaller than that of the intralayer exciton due to the spatial separation of electron and hole to the opposite layers. These results lay the foundation for exploiting the interlayer exciton in future 2D heterostructure optoelectronic devices.

  6. High-Speed Scalable Silicon-MoS2 P-N Heterojunction Photodetectors

    Science.gov (United States)

    Dhyani, Veerendra; Das, Samaresh

    2017-01-01

    Two-dimensional molybdenum disulfide (MoS2) is a promising material for ultrasensitive photodetector owing to its favourable band gap and high absorption coefficient. However, their commercial applications are limited by the lack of high quality p-n junction and large wafer scale fabrication process. A high speed Si/MoS2 p-n heterojunction photodetector with simple and CMOS compatible approach has been reported here. The large area MoS2 thin film on silicon platform has been synthesized by sulfurization of RF-sputtered MoO3 films. The fabricated molecular layers of MoS2 on silicon offers high responsivity up to 8.75 A/W (at 580 nm and 3 V bias) with ultra-fast response of 10 μsec (rise time). Transient measurements of Si/MoS2 heterojunction under the modulated light reveal that the devices can function up to 50 kHz. The Si/MoS2 heterojunction is found to be sensitive to broadband wavelengths ranging from visible to near-infrared light with maximum detectivity up to ≈1.4 × 1012 Jones (2 V bias). Reproducible low dark current and high responsivity from over 20 devices in the same wafer has been measured. Additionally, the MoS2/Si photodetectors exhibit excellent stability in ambient atmosphere. PMID:28281652

  7. Solar-energy conversion and light emission in an atomic monolayer p-n diode.

    Science.gov (United States)

    Pospischil, Andreas; Furchi, Marco M; Mueller, Thomas

    2014-04-01

    The limitations of the bulk semiconductors currently used in electronic devices-rigidity, heavy weight and high costs--have recently shifted the research efforts to two-dimensional atomic crystals such as graphene and atomically thin transition-metal dichalcogenides. These materials have the potential to be produced at low cost and in large areas, while maintaining high material quality. These properties, as well as their flexibility, make two-dimensional atomic crystals attractive for applications such as solar cells or display panels. The basic building blocks of optoelectronic devices are p-n junction diodes, but they have not yet been demonstrated in a two-dimensional material. Here, we report a p-n junction diode based on an electrostatically doped tungsten diselenide (WSe2) monolayer. We present applications as a photovoltaic solar cell, a photodiode and a light-emitting diode, and obtain light-power conversion and electroluminescence efficiencies of ∼ 0.5% and ∼ 0.1%, respectively. Given recent advances in the large-scale production of two-dimensional crystals, we expect them to profoundly impact future developments in solar, lighting and display technologies.

  8. The X-ray mirror telescope and the pn-CCD detector of CAST

    CERN Document Server

    Kuster, M; Englhauser, J; Franz, J; Friedrich, P; Hartmann, R; Kang, D; Kotthaus, R; Lutz, Gerhard; Moralez, J; Serber, W; Strüder, L

    2004-01-01

    The Cern Axion Solar Telescope - CAST - uses a prototype 9 Tesla LHC superconducting dipole magnet to search for a hypothetical pseudoscalar particle, the axion, which was proposed by theory in the 1980s to solve the strong CP problem and which could be a dark matter candidate. In CAST a strong magnetic field is used to convert the solar axions to detectable photons via inverse Primakoff effect. The resulting X-rays are thermally distributed in the energy range of 1-7 keV and can be observed with conventional X-ray detectors. The most sensitive detector system of CAST is a pn-CCD detector originally developed for XMM-Newton combined with a Wolter I type X-ray mirror system. The combination of a focusing X-ray optics and a state of the art pn-CCD detector which combines high quantum efficiency, good spacial and energy resolution, and low background improves the sensitivity of the CAST experiment such that for the first time the axion photon coupling constant can be probed beyond the best astrophysical constrai...

  9. Flexible Photodiodes Based on Nitride Core/Shell p-n Junction Nanowires.

    Science.gov (United States)

    Zhang, Hezhi; Dai, Xing; Guan, Nan; Messanvi, Agnes; Neplokh, Vladimir; Piazza, Valerio; Vallo, Martin; Bougerol, Catherine; Julien, François H; Babichev, Andrey; Cavassilas, Nicolas; Bescond, Marc; Michelini, Fabienne; Foldyna, Martin; Gautier, Eric; Durand, Christophe; Eymery, Joël; Tchernycheva, Maria

    2016-10-05

    A flexible nitride p-n photodiode is demonstrated. The device consists of a composite nanowire/polymer membrane transferred onto a flexible substrate. The active element for light sensing is a vertical array of core/shell p-n junction nanowires containing InGaN/GaN quantum wells grown by MOVPE. Electron/hole generation and transport in core/shell nanowires are modeled within nonequilibrium Green function formalism showing a good agreement with experimental results. Fully flexible transparent contacts based on a silver nanowire network are used for device fabrication, which allows bending the detector to a few millimeter curvature radius without damage. The detector shows a photoresponse at wavelengths shorter than 430 nm with a peak responsivity of 0.096 A/W at 370 nm under zero bias. The operation speed for a 0.3 × 0.3 cm(2) detector patch was tested between 4 Hz and 2 kHz. The -3 dB cutoff was found to be ∼35 Hz, which is faster than the operation speed for typical photoconductive detectors and which is compatible with UV monitoring applications.

  10. Efficient p-n junction-based thermoelectric generator that can operate at extreme temperature conditions

    Science.gov (United States)

    Chavez, Ruben; Angst, Sebastian; Hall, Joseph; Maculewicz, Franziska; Stoetzel, Julia; Wiggers, Hartmut; Thanh Hung, Le; Van Nong, Ngo; Pryds, Nini; Span, Gerhard; Wolf, Dietrich E.; Schmechel, Roland; Schierning, Gabi

    2018-01-01

    In many industrial processes, a large proportion of energy is lost in the form of heat. Thermoelectric generators can convert this waste heat into electricity by means of the Seebeck effect. However, the use of thermoelectric generators in practical applications on an industrial scale is limited in part because electrical, thermal, and mechanical bonding contacts between the semiconductor materials and the metal electrodes in current designs are not capable of withstanding thermal-mechanical stress and alloying of the metal–semiconductor interface when exposed to the high temperatures occurring in many real-world applications. Here we demonstrate a concept for thermoelectric generators that can address this issue by replacing the metallization and electrode bonding on the hot side of the device by a p-n junction between the two semiconductor materials, making the device robust against temperature induced failure. In our proof-of-principle demonstration, a p-n junction device made from nanocrystalline silicon is at least comparable in its efficiency and power output to conventional devices of the same material and fabrication process, but with the advantage of sustaining high hot side temperatures and oxidative atmosphere.

  11. Horizontal Silicon Nanowires with Radial p-n Junctions: A Platform for Unconventional Solar Cells.

    Science.gov (United States)

    Zhang, Xing; Pinion, Christopher W; Christesen, Joseph D; Flynn, Cory J; Celano, Thomas A; Cahoon, James F

    2013-06-20

    The silicon p-n junction is the most successful solar energy technology to date, yet it accounts for a marginal percentage of worldwide energy production. To change the status quo, a disruptive technological breakthrough is needed. In this Perspective, we discuss the potential for complex silicon nanowires to serve as a platform for next-generation photovoltaic devices. We review the synthesis, electrical characteristics, and optical properties of core/shell silicon nanowires that are subwavelength in diameter and contain radial p-n junctions. We highlight the unique features of these nanowires, such as optical antenna effects that concentrate light and intense built-in electric fields that enable ultrafast charge-carrier separation. We advocate a paradigm in which nanowires are arranged in periodic horizontal arrays to form ultrathin devices. Unlike conventional planar silicon, nanowire structures provide the flexibility to incorporate multiple semiconductor, dielectric, and metallic materials in a single system, providing the foundation for a disruptive, unconventional solar energy technology.

  12. The problem of crowd crimes: the approach of P.N. Obninskiy

    Directory of Open Access Journals (Sweden)

    Gorbatov D.S.

    2014-09-01

    Full Text Available We describe the specific approach to crowd crimes proposed by prominent Russian lawyer and public figure of the XIX century P.N. Obninskiy. We clarify its fundamental differences from other concepts of Russian and foreign psychologists and lawyers. Particular attention is paid to the P.N. Obninskiy treatment of possible sanity and responsibility of participants of mass cholera riots of the late XIX century in various regions of the Russian Empire. We reveal the moral potential of his views. Crowd as a social associations, the personality changes in the crowd, the crowd propensity to violate the law, the issue of punishment for crimes committed by it – these are some of the questions that interested the public opinion of the time. The article emphasizes that the lack of trust and lack of equal dialogue between representatives of different social groups have played a negative role in the development of «contagion morale», and later became reasons for the even more tragic events of Russian history.

  13. Infrared detector based on interband transition of semiconductor quantum well within p-n junction

    Science.gov (United States)

    Sun, Ling; Liu, Jie; Jia, Haiqiang; Wang, Wenxin; Wang, Lu; Chen, Hong

    2017-10-01

    Resonant excited carriers in quantum well will relax to the ground states and cannot escape from quantum wells to form photocurrent. However, it was recently observed that most of the photo-excited carriers in InGaAs/GaAs quantum wells within a p-n junction escape from quantum wells and form photocurrent rather than relax to the ground state of the quantum wells. The absorption coefficient of multiple quantum wells is also enhanced by a p-n junction. According to the phenomenon, a novel photon detector based on interband transition of strained InGaAs/GaAs quantum wells was fabricated. Without an anti-reflection layer, the external quantum efficiency up to 31% with only 100 nm absorption thickness was measured, corresponding an absorption coefficient of 3.7×104 cm-1 that is obviously higher than previously reported values. The room temperature detectivity of the device was 1.43×1013 cm Hz1/2 W-1. For strained InAsSb/GaSb quantum wells material system, the detector showed a narrow response range from 2.1 μm to 3.0 μm with a peak around 2.6 μm at 200 K and a wide response range from 3.5 μm to 5.7 μm. The photon detectors based on interband transition show great potential applications in infrared detection operating at high temperature.

  14. Fabrication of a GaN p/n lateral polarity junction by polar doping selectivity

    Energy Technology Data Exchange (ETDEWEB)

    Collazo, Ramon; Mita, Seiji; Rice, Anthony; Dalmau, Rafael; Sitar, Zlatko [Department of Materials Science and Engineering, North Carolina State University, Raleigh, NC (United States); Wellenius, Patrick; Muth, John [Department of Electrical and Computer Engineering, North Carolina State University, Raleigh, NC (United States)

    2008-07-01

    The difference in surface energy between the Ga-polar orientation and the N-polar orientation of GaN translates into a completely different behavior for the incorporation of intentional and unintentional impurities. Oxygen is found to be an impurity with higher concentration in N-polar films than in Ga-polar films and is the cause for the high carrier concentration observed in N-polar films. We fabricated a lateral p/n junction in GaN by the simultaneous growth of p- and n-type regions, utilizing the doping selectivity of the two different polar domains, which resulted in an n-type carrier concentration of 1.7x10{sup 19} cm{sup -3} with an electron Hall mobility of 99 cm{sup 2}/Vs in the N-polar domains, and a p-type carrier concentration of 1.1 x 10{sup 17} cm{sup -3} with a hole Hall mobility of 12 cm{sup 2}/Vs in the Ga-polar domains. These junctions showed the characteristics that define a p/n junction: current rectification, electroluminescence, and photo-effect. (copyright 2008 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  15. XSHOOTER spectroscopy of the enigmatic PN Lin49 in the SMC

    Science.gov (United States)

    Otsuka, Masaaki; Kemper, Francisca; Leal-Ferreira, Marcelo L.; Aleman, Isabel; Bernard-Salas, Jeronimo; Cami, Jan; Ochsendorf, Bram B.; Peeters, Els; Scicluna, Peter

    2017-10-01

    We performed a detailed spectroscopic analysis of the fullerene C60-containing planetary nebula (PN) Lin49 in the Small Magellanic Cloud (SMC). Lin49 is a C-rich and metal-deficient PN (Z~0.0006) and its nebular abundances are in agreement with the AGB model for the initially 1.25 M ⊙ stars with the metallicity Z = 0.001. By stellar absorption fitting with TLUSTY, we derived stellar abundances, effective temperature, and surface gravity. We constructed the photoionization model with CLOUDY in order to investigate physical conditions of Lin49. The model with the 0.005-0.1 μm radius graphite and a constant hydrogen density shell could not fit the ~1-5 μm spectral energy distribution (SED) owing to the strong near-IR excess. We propose that the near-IR excess indicates (1) the presence of extremely small carbon molecules or (2) the presence of high-density structure surrounding the central star.

  16. Lateral MoS2 p-n junction formed by chemical doping for use in high-performance optoelectronics.

    Science.gov (United States)

    Choi, Min Sup; Qu, Deshun; Lee, Daeyeong; Liu, Xiaochi; Watanabe, Kenji; Taniguchi, Takashi; Yoo, Won Jong

    2014-09-23

    This paper demonstrates a technique to form a lateral homogeneous 2D MoS2 p-n junction by partially stacking 2D h-BN as a mask to p-dope MoS2. The fabricated lateral MoS2 p-n junction with asymmetric electrodes of Pd and Cr/Au displayed a highly efficient photoresponse (maximum external quantum efficiency of ∼7000%, specific detectivity of ∼5 × 10(10) Jones, and light switching ratio of ∼10(3)) and ideal rectifying behavior. The enhanced photoresponse and generation of open-circuit voltage (VOC) and short-circuit current (ISC) were understood to originate from the formation of a p-n junction after chemical doping. Due to the high photoresponse at low VD and VG attributed to its built-in potential, our MoS2 p-n diode made progress toward the realization of low-power operating photodevices. Thus, this study suggests an effective way to form a lateral p-n junction by the h-BN hard masking technique and to improve the photoresponse of MoS2 by the chemical doping process.

  17. A Psychometric Evaluation of a Swedish Version of the Positive–Negative Sex-Role Inventory (PN-SRI

    Directory of Open Access Journals (Sweden)

    Therese Rydberg Sterner

    2018-02-01

    Full Text Available The Positive–Negative Sex-Role Inventory (PN-SRI assesses gender identity. The aim of this study was to evaluate the validity and reliability of a Swedish version of the PN-SRI in a population of 70-year-olds within the Gothenburg H70-study in Sweden. The overarching objective of testing the PN-SRI within the H70-study was to evaluate its usability to further study gender identity in large population-based samples of older adults. A total of 1124 individuals participated in the psychometric testing. A sub-sample of these (n = 406 provided a comprehensive survey regarding societal norms on femininity and masculinity. Reliability and validity tests were performed using Cronbach’s Alpha and factor analyses. The Cronbach’s α coefficients (0.734–0.787 indicated a satisfactory level of internal consistency, and the four-factor model (Model 2 fitted the data at an acceptable level (root-mean-square error of approximation, RMSEA = 0.068, standardized root-mean-square residual, SRMR = 0.07. This cross-cultural adaptation of the PN-SRI indicates that it may be applicable in a Swedish research setting comprising older adults. Future research is needed to further test the psychometric properties of this scale. Adding the PN-SRI to population-based studies will contribute to providing a nuanced way of analyzing differences and similarities among men and women.

  18. Anafylaktisk shock efter intradermal injektion af steroidpræparat

    DEFF Research Database (Denmark)

    Meyer, Martin Willy; Zachariae, Claus; Garvey, Lene Heise

    2015-01-01

    nodularis of Hyde, who reacted with anaphylaxis after intradermal injection of Kenalog 40 mg/ml. Allergy testing showed a positive skin prick test for CMC and the patient was advised to avoid future parenteral exposure to CMC. This case highlights the need to examine excipients in severe cases of drug......Carboxymethylcellulose (CMC) is a derivative of cellulose found in many food products, pharmaceuticals and cosmetics. Allergy to CMC in parenteral corticosteroid preparations leading to anaphylaxis is rare, but has previously been reported. We report a case of a 52-year-old woman with prurigo...... allergy....

  19. Anafylaktisk shock efter intradermal injektion af steroidpræparat

    DEFF Research Database (Denmark)

    Meyer, Martin Willy; Zachariae, Claus; Garvey, Lene Heise

    2015-01-01

    Carboxymethylcellulose (CMC) is a derivative of cellulose found in many food products, pharmaceuticals and cosmetics. Allergy to CMC in parenteral corticosteroid preparations leading to anaphylaxis is rare, but has previously been reported. We report a case of a 52-year-old woman with prurigo...... nodularis of Hyde, who reacted with anaphylaxis after intradermal injection of Kenalog 40 mg/ml. Allergy testing showed a positive skin prick test for CMC and the patient was advised to avoid future parenteral exposure to CMC. This case highlights the need to examine excipients in severe cases of drug...

  20. Anafylaktisk shock efter intradermal injektion afsteroidpræparat

    DEFF Research Database (Denmark)

    Meyer, Martin Willy; Zachariae, Claus; Garvey, Lene Heise

    2015-01-01

    Carboxymethylcellulose (CMC) is a derivative of cellulose found in many food products, pharmaceuticals and cosmetics. Allergy to CMC in parenteral corticosteroid preparations leading to anaphylaxis is rare, but has previously been reported. We report a case of a 52-year-old woman with prurigo...... nodularis of Hyde, who reacted with anaphylaxis after intradermal injection of Kenalog 40 mg/ml. Allergy testing showed a positive skin prick test for CMC and the patient was advised to avoid future parenteral exposure to CMC. This case highlights the need to examine excipients in severe cases of drug...

  1. Anafylaktisk shock efter intradermal injektion af steroidpræparat

    DEFF Research Database (Denmark)

    Meyer, Martin Willy; Zachariae, Claus Otto Carl; Garvey, Lene Heise

    2015-01-01

    Anaphylactic shock after intradermal injection of corticosteroid Carboxymethylcellulose (CMC) is a derivative of cellulose found in many food products, pharmaceuticals and cosmetics. Allergy to carboxymethylcellulose in parenteral corticosteroid preparations leading to anaphylaxis is rare, but has...... previously been reported. We report a case of a 52-year-old woman with prurigo nodularis of Hyde, who reacted with anaphylaxis after intradermal injection of Kenalog 40 mg/ml. Allergy testing showed a positive skin prick test for CMC and the patient was advised to avoid future parenteral exposure to CMC...

  2. Prevalence of dermatoses in dermatologic evaluation requests from patients admitted to a tertiary hospital for 10 years*

    Science.gov (United States)

    Dantas, Lia Dias Pinheiro; Bakos, Lucio; Balbinot, Gabriela; Drechsler, Carine Elisabete Rost; Eidt, Letícia Maria

    2015-01-01

    Skin diseases are common in hospitalized patients. However, there is a lack of data concerning their frequency. The objective of this study is to evaluate the prevalence of dermatological diagnoses in hospitalized patients after consultation requested by nondermatologist physicians to the Department of Dermatology, Hospital de Clinicas de Porto Alegre period of 10 years. A total of 5685 patients were evaluated, representing an average of 48.2 patients per month. The five most frequent groups were infectious dermatoses(33.25%), eczematous dermatoses (11.49%), drug reactions (11.43%), vascular dermatoses (6.81%) and group of pruritus, prurigo nodularis and urticaria (hives) (4.71%). PMID:26560228

  3. Simulation and parametric analysis of graphene p-n junctions with two rectangular top gates and a single back gate

    Science.gov (United States)

    Nikiforidis, Ioannis; Karafyllidis, Ioannis G.; Dimitrakis, Panagiotis

    2018-02-01

    Graphene p-n junctions could be the building blocks of future nanoelectronic circuits. While the conductance modulation of graphene p-n junctions formed in devices with one bottom and one top gate have received much attention, there is comparatively little work done on devices with two top gates. Here, we employ tight-bind Hamiltonians and non-equilibrium Green function method to compute in a systematic way the dependence of the conductance of graphene p-n junctions, formed in a device with two top gates, on the device parameters. We present our results in a compact and systematic way, so that the effect of each parameter is clearly shown. Our results show that the device conductance can be effectively modulated, and that graphene devices with two top gates may be used as basic elements in future carbon-based nanoelectronic circuits.

  4. Integrated CLOS and PN Guidance for Increased Effectiveness of Surface to Air Missiles

    Directory of Open Access Journals (Sweden)

    Binte Fatima Tuz ZAHRA

    2017-06-01

    Full Text Available In this paper, a novel approach has been presented to integrate command to line-of-sight (CLOS guidance and proportional navigation (PN guidance in order to reduce miss distance and to increase the effectiveness of surface to air missiles. Initially a comparison of command to line-of-sight guidance and proportional navigation has been presented. Miss distance, variation of angle-of-attack, normal and lateral accelerations and error of missile flight path from direct line-of-sight have been used as noteworthy criteria for comparison of the two guidance laws. Following this comparison a new approach has been proposed for determining the most suitable guidance gains in order to minimize miss distance and improve accuracy of the missile in delivering the warhead, while using CLOS guidance. This proposed technique is based on constrained nonlinear minimization to optimize the guidance gains. CLOS guidance has a further limitation of significant increase in normal and lateral acceleration demands during the terminal phase of missile flight. Furthermore, at large elevation angles, the required angle-of-attack during the terminal phase increases beyond design specifications. Subsequently, a missile with optical sensors only and following just the CLOS guidance has less likelihood to hit high speed targets beyond 45º in elevation plane. A novel approach has thus been proposed to overcome such limitations of CLOS-only guidance for surface to air missiles. In this approach, an integrated guidance algorithm has been proposed whereby the initial guidance law during rocket motor burnout phase remains CLOS, whereas immediately after this phase, the guidance law is automatically switched to PN guidance. This integrated approach has not only resulted in slight increase in range of the missile but also has significantly improved its likelihood to hit targets beyond 30 degrees in elevation plane, thus successfully overcoming various limitations of CLOS

  5. Construction of two-dimensional MoS₂/CdS p-n nanohybrids for highly efficient photocatalytic hydrogen evolution.

    Science.gov (United States)

    Zhang, Jian; Zhu, Zhenping; Feng, Xinliang

    2014-08-18

    2D MoS2 nanosheets have been utilized to fabricate 2D MoS2/CdS p-n nanohybrids through a one-pot solvothermal process. Due to the unique p-n junction heterostructure, large specific surface area, and decreased band gap, MoS2/CdS nanohybrids manifested a superior H2 -production rate of ~137 μmol h(-1) under visible-light irradiation and an apparent quantum yield of 10.5% at 450 nm. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Inductively Coupled Plasma-Induced Etch Damage of GaN p-n Junctions

    Energy Technology Data Exchange (ETDEWEB)

    SHUL,RANDY J.; ZHANG,LEI; BACA,ALBERT G.; WILLISON,CHRISTI LEE; HAN,JUNG; PEARTON,S.J.; REN,F.

    1999-11-03

    Plasma-induced etch damage can degrade the electrical and optical performance of III-V nitride electronic and photonic devices. We have investigated the etch-induced damage of an Inductively Coupled Plasma (ICP) etch system on the electrical performance of mesa-isolated GaN pn-junction diodes. GaN p-i-n mesa diodes were formed by Cl{sub 2}/BCl{sub 3}/Ar ICP etching under different plasma conditions. The reverse leakage current in the mesa diodes showed a strong relationship to chamber pressure, ion energy, and plasma flux. Plasma induced damage was minimized at moderate flux conditions ({le} 500 W), pressures {ge}2 mTorr, and at ion energies below approximately -275 V.

  7. ZnO PN Junctions for Highly-Efficient, Low-Cost Light Emitting Diodes

    Energy Technology Data Exchange (ETDEWEB)

    David P. Norton; Stephen Pearton; Fan Ren

    2007-09-30

    By 2015, the US Department of Energy has set as a goal the development of advanced solid state lighting technologies that are more energy efficient, longer lasting, and more cost-effective than current technology. One approach that is most attractive is to utilize light-emitting diode technologies. Although III-V compound semiconductors have been the primary focus in pursuing this objective, ZnO-based materials present some distinct advantages that could yield success in meeting this objective. As with the nitrides, ZnO is a direct bandgap semiconductor whose gap energy (3.2 eV) can be tuned from 3.0 to 4 eV with substitution of Mg for higher bandgap, Cd for lower bandgap. ZnO has an exciton binding energy of 60 meV, which is larger than that for the nitrides, indicating that it should be a superior light emitting semiconductor. Furthermore, ZnO thin films can be deposited at temperatures on the order of 400-600 C, which is significantly lower than that for the nitrides and should lead to lower manufacturing costs. It has also been demonstrated that functional ZnO electronic devices can be fabricated on inexpensive substrates, such as glass. Therefore, for the large-area photonic application of solid state lighting, ZnO holds unique potential. A significant impediment to exploiting ZnO in light-emitting applications has been the absence of effective p-type carrier doping. However, the recent realization of acceptor-doped ZnO material overcomes this impediment, opening the door to ZnO light emitting diode development In this project, the synthesis and properties of ZnO-based pn junctions for light emitting diodes was investigated. The focus was on three issues most pertinent to realizing a ZnO-based solid state lighting technology, namely (1) achieving high p-type carrier concentrations in epitaxial and polycrystalline films, (2) realizing band edge emission from pn homojunctions, and (3) investigating pn heterojunction constructs that should yield efficient light

  8. Spin-Based Mach-Zehnder Interferometry in Topological Insulator p-n Junctions.

    Science.gov (United States)

    Ilan, Roni; de Juan, Fernando; Moore, Joel E

    2015-08-28

    Transport in three-dimensional topological insulators relies on the existence of a spin-momentum locked surface state that encloses the insulating bulk. In this work we show how, in a topological insulator p-n junction, a magnetic field turns this surface state into an electronic Mach-Zehnder interferometer. Transmission of the junction can be tuned from zero to unity, resulting in virtually perfect visibility of the interference pattern, and the reflected and transmitted currents carry opposite spin polarization so that the junction also acts as a spin filter. Our setup therefore realizes a novel and highly tunable spintronic device where the effects of spin-momentum locking in topological insulator surface states can be probed directly in a transport experiment.

  9. Complete gate control of supercurrent in graphene p-n junctions.

    Science.gov (United States)

    Choi, Jae-Hyun; Lee, Gil-Ho; Park, Sunghun; Jeong, Dongchan; Lee, Jeong-O; Sim, H-S; Doh, Yong-Joo; Lee, Hu-Jong

    2013-01-01

    In a conventional Josephson junction of graphene, the supercurrent is not turned off even at the charge neutrality point, impeding further development of superconducting quantum information devices based on graphene. Here we fabricate bipolar Josephson junctions of graphene, in which a p-n potential barrier is formed in graphene with two closely spaced superconducting contacts, and realize supercurrent ON/OFF states using electrostatic gating only. The bipolar Josephson junctions of graphene also show fully gate-driven macroscopic quantum tunnelling behaviour of Josephson phase particles in a potential well, where the confinement energy is gate tuneable. We suggest that the supercurrent OFF state is mainly caused by a supercurrent dephasing mechanism due to a random pseudomagnetic field generated by ripples in graphene, in sharp contrast to other nanohybrid Josephson junctions. Our study may pave the way for the development of new gate-tuneable superconducting quantum information devices.

  10. Gravitational-wave phasing for low-eccentricity inspiralling compact binaries to 3PN order

    CERN Document Server

    Moore, Blake; Arun, K G; Mishra, Chandra Kant

    2016-01-01

    [abridged] Although gravitational radiation causes inspiralling compact binaries to circularize, a variety of astrophysical scenarios suggest that binaries might have small but nonnegligible orbital eccentricities when they enter the low-frequency bands of ground and space-based gravitational-wave detectors. If not accounted for, even a small orbital eccentricity can cause a potentially significant systematic error in the mass parameters of an inspiralling binary. Gravitational-wave search templates typically rely on the quasi-circular approximation, which provides relatively simple expressions for the gravitational-wave phase to 3.5 post-Newtonian (PN) order. The quasi-Keplerian formalism provides an elegant but complex description of the post-Newtonian corrections to the orbits and waveforms of inspiralling binaries with any eccentricity. Here we specialize the quasi-Keplerian formalism to binaries with low eccentricity. In this limit the non-periodic contribution to the gravitational-wave phasing can be ex...

  11. PEMBATALAN MEREK DI PENGADILAN NIAGA MEDAN (Studi Putusan No. 03/Merek/2008/PN.Niaga/Medan

    Directory of Open Access Journals (Sweden)

    Mandras Mandras

    2013-12-01

    Full Text Available Filosofi perlindungan atas kekayaan intelektual yang bermanfaat bagi pengembangan ekonomi dan teknologi bagi mayarakat lokal yang pertama A Normative Justification dan Kedua A Nationalistic Justification. Adapun manfaat yang bisa dirasakan oleh masyarakat, yaitu mereka mendapatkan barang yang asli, bukan tiruan. Akan tumbuh juga di dalam masyarakat semangat untuk terus berkreasi karena telah merasakan manfaat positifnya. Adanya kreativitas yang tinggi di antara sesama produsen diharapkan bisa meningkatkan daya saing produk karena selalu ada inovasi. Merek diatur dalam Undang-Undang No. 15 Tahun 2001, dimana merek sendiri merupakan bagian salah satu Hak Kekayaan Intelektual, yang merupakan ”hak milik” seseorang/beberapa orang secara bersama-sama bersifat mutlak, eksklusif serta mempunyai jangka waktu yang terbatas. Sebagai kekayaan bagi pemiliknya, merek mempunyai manfaat dan berguna bagi kehidupan manusia serta bernilai ekonomis. Sebagai hak kekayaan intelektual merek juga memiliki aspek sengketa, dimana dalam kajian ini akan dibahas tentang pembatalan merek dengan menganalisis Putusan No. 03/Merek/2008/PN.Niaga/Medan.

  12. p-n Heterojunction of doped graphene films obtained by pyrolysis of biomass precursors.

    Science.gov (United States)

    Latorre-Sánchez, Marcos; Primo, Ana; Atienzar, Pedro; Forneli, Amparo; García, Hermenegildo

    2015-02-25

    Nitrogen-doped graphene [(N)G] obtained by pyrolysis at 900 °C of nanometric chitosan films exhibits a Hall effect characteristic of n-type semiconductors. In contrast, boron-doped graphene [(B)G] obtained by pyrolysis of borate ester of alginate behaves as a p-type semiconductor based also on the Hall effect. A p-n heterojunction of (B)G-(N)G films is built by stepwise coating of a quartz plate using a mask. The heterojunction is created by the partial overlapping of the (B)G-(N)G films. Upon irradiation with a xenon lamp of aqueous solutions of H(2) PtCl(6) and MnCl(2) in contact with the heterojunction, preferential electron migration from (B)G to (N)G with preferential location of positive holes on (B)G is established by observation in scanning electron microscopy of the formation of Pt nanoparticles (NP) on (N)G and MnO(2) NP on (B)G. The benefits of the heterojunction with respect to the devices having one individual component as a consequence of the electron migration through the p-n heterojunction are illustrated by measuring the photocurrent in the (B)G-(N)G heterojunction (180% current enhancement with respect to the dark current) and compared it to the photocurrent of the individual (B)G (15% enhancement) and (N)G (55% enhancement) components. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. A crust and upper mantle model of Eurasia and North Africa for Pn travel time calculation

    Energy Technology Data Exchange (ETDEWEB)

    Myers, S; Begnaud, M; Ballard, S; Pasyanos, M; Phillips, W S; Ramirez, A; Antolik, M; Hutchenson, K; Dwyer, J; Rowe, C; Wagner, G

    2009-03-19

    We develop a Regional Seismic Travel Time (RSTT) model and methods to account for the first-order effect of the three-dimensional crust and upper mantle on travel times. The model parameterization is a global tessellation of nodes with a velocity profile at each node. Interpolation of the velocity profiles generates a 3-dimensional crust and laterally variable upper mantle velocity. The upper mantle velocity profile at each node is represented as a linear velocity gradient, which enables travel time computation in approximately 1 millisecond. This computational speed allows the model to be used in routine analyses in operational monitoring systems. We refine the model using a tomographic formulation that adjusts the average crustal velocity, mantle velocity at the Moho, and the mantle velocity gradient at each node. While the RSTT model is inherently global and our ultimate goal is to produce a model that provides accurate travel time predictions over the globe, our first RSTT tomography effort covers Eurasia and North Africa, where we have compiled a data set of approximately 600,000 Pn arrivals that provide path coverage over this vast area. Ten percent of the tomography data are randomly selected and set aside for testing purposes. Travel time residual variance for the validation data is reduced by 32%. Based on a geographically distributed set of validation events with epicenter accuracy of 5 km or better, epicenter error using 16 Pn arrivals is reduced by 46% from 17.3 km (ak135 model) to 9.3 km after tomography. Relative to the ak135 model, the median uncertainty ellipse area is reduced by 68% from 3070 km{sup 2} to 994 km{sup 2}, and the number of ellipses with area less than 1000 km{sup 2}, which is the area allowed for onsite inspection under the Comprehensive Nuclear Test Ban Treaty, is increased from 0% to 51%.

  14. Horizontal Assembly of Single Nanowire Diode Fabricated by p-n Junction GaN NW Grown by MOCVD

    Directory of Open Access Journals (Sweden)

    Ji-Hyeon Park

    2014-01-01

    Full Text Available Uniaxially p-n junction gallium nitride nanowires have been synthesized via metal-organic chemical vapor deposition method. Nanowires prepared on Si(111 substrates were found to grow perpendicular to the substrate, and the transmission electron microscopy studies demonstrated that the nanowires had singlecrystalline structures with a growth axis. The parallel assembly of the p-n junction nanowire was prepared on a Si substrate with a thermally grown SiO2 layer. The transport studies of horizontal gallium nitride nanowire structures assembled from p- and n-type materials show that these junctions correspond to well-defined p-n junction diodes. The p-n junction devices based on GaN nanowires suspended over the electrodes were fabricated and their electrical properties were investigated. The horizontally assembled gallium nitride nanowire diodes suspended over the electrodes exhibited a substantial increase in conductance under UV light exposure. Apart from the selectivity to different light wavelengths, high responsivity and extremely short response time have also been obtained.

  15. Electrostatically tunable lateral MoTe2 p-n junction for use in high-performance optoelectronics.

    Science.gov (United States)

    Wang, Zhenxing; Wang, Feng; Yin, Lei; Huang, Yun; Xu, Kai; Wang, Fengmei; Zhan, Xueying; He, Jun

    2016-07-21

    Because of their ultimate thickness, layered structure and high flexibility, pn junctions based on layered two-dimensional semiconductors have been attracting increasing attention recently. In this study, for the first time, we fabricated lateral pn junctions (LPNJs) based on ultrathin MoTe2 by introducing two separated electrostatic back gates, and investigated their electronic and photovoltaic performance. Pn, np, nn, and pp junctions can be easily realized by modulating the conductive channel type using gate voltages with different polarities. Strong rectification effects were observed in the pn and np junctions and the rectification ratio reached ∼5 × 10(4). Importantly, we find a unique phenomenon that the parameters for MoTe2 LPNJs experience abrupt changes during the transition from p to n or n to p. Furthermore, a high performance photovoltaic device with a filling factor of above 51% and electrical conversion efficiency (η) of around 0.5% is achieved. Our findings are of importance to comprehensively understand the electronic and optoelectronic properties of MoTe2 and may further open up novel electronic and optoelectronic device applications.

  16. Formation of a Stable p-n Junction in a Liquid-Gated MoS2 Ambipolar Transistor

    NARCIS (Netherlands)

    Zhang, Y. J.; Ye, J. T.; Yornogida, Y.; Takenobu, T.; Iwasa, Y.

    Molybdenum disulfide (MoS2) has gained attention because of its high mobility and circular dichroism. As a crucial step to merge these advantages into a single device, we present a method that electronically controls and locates p-n junctions in liquid-gated ambipolar MoS2 transistors. A

  17. The behavior of series resistance of a p-n junction: the diode and the solar cell cases

    Science.gov (United States)

    Bueno, Poliana H.; Costa, Diogo F.; Eick, Alexander; Carvalho, André; Monteiro, Davies W. L.

    2016-03-01

    This paper presents a comparison of the impact of the internal parasitic series resistance of a p-n junction, as seen from the microelectronics and photovoltaic communities. The elusive thermal behavior of the aforementioned resistance gave this work its origin. Each community uses a different approach to interpret the operational current-voltage behavior of a p-n junction, which might lead to confusion, since scientists and engineers of these two realms seldom interact. An improvement in the understanding of the different approaches will help one to better model the performance of devices based on p-n junctions and therefore it will favor the performance predictions of photovoltaic cells. For diodes, series resistance is usually determined from a specific forward-bias region of the I-V curve on a semi-logarithmic scale. However, in Photovoltaics this region is not commonly reported and therefore other methods to determine Rs are employed. We mathematically modeled an experimentally obtained I-V curve with various pairs of the ideality factor and Rs and found that more than one pair accurately synthesizes the measured curve. We can conclude that the reported series resistance not only depends on physical parameters, e.g. temperature or irradiance, but also on fitting parameters, i.e. the ideality factor. Generally the behavior of a p-n junction depends on its operating conditions and electrical modeling.

  18. The PN.S elliptical galaxy survey : Data reduction, planetary nebula catalog, and basic dynamics for NGC 3379

    NARCIS (Netherlands)

    Douglas, N. G.; Napolitano, N. R.; Romanowsky, A. J.; Coccato, L.; Kuijken, K.; Merrifield, M. R.; Arnaboldi, M.; Gerhard, O.; Freeman, K. C.; Merrett, H. R.; Noordermeer, E.; Capaccioli, M.

    2007-01-01

    We present results from Planetary Nebula Spectrograph (PN. S) observations of the elliptical galaxy NGC 3379 and a description of the data reduction pipeline. We detected 214 planetary nebulae, of which 191 are ascribed to NGC 3379 and 23 to the companion galaxy NGC 3384. Comparison with data from

  19. The effect of PN-1, a Traditional Chinese Prescription, on the Learning and Memory in a Transgenic Mouse Model of Alzheimer’s Disease

    Directory of Open Access Journals (Sweden)

    Zhi-Gang Yao

    2013-01-01

    Full Text Available Traditional Chinese Medicine (TCM is a complete medical system that has been practiced for more than 3000 years. Prescription number 1 (PN-1 consists of several Chinese medicines and is designed according to TCM theories to treat patients with neuropsychiatric disorders. The evidence of clinical practice suggests the benefit effects of PN-1 on cognitive deficits of dementia patients. We try to prove and explain this by using contemporary methodology and transgenic animal models of Alzheimer’s disease (AD. The behavioral studies were developed to evaluate the memory of transgenic animals after intragastric administration of PN-1 for 3 months. Amyloid beta-protein (Aβ neuropathology was quantified using immunohistochemistry and ELISA. The western blotting was used to detect the levels of plasticity associated proteins. The safety of PN-1 on mice was also assessed through multiple parameters. Results showed that PN-1 could effectively relieve learning and memory impairment of transgenic animals. Possible mechanisms showed that PN-1 could significantly reduce plaque burden and Aβ levels and boost synaptic plasticity. Our observations showed that PN-1 could improve learning and memory ability through multiple mechanisms without detectable side effects on mice. We propose that PN-1 is a promising alternative treatment for AD in the future.

  20. Serpine2/PN-1 Is Required for Proliferative Expansion of Pre-Neoplastic Lesions and Malignant Progression to Medulloblastoma

    Science.gov (United States)

    Vaillant, Catherine; Kool, Marcel; Schwarzentruber-Schauerte, Alexandra; Méreau, Hélène; Cabuy, Erik; Lobrinus, Johannes A.; Pfister, Stefan; Zuniga, Aimée; Frank, Stephan; Zeller, Rolf

    2015-01-01

    Background Medulloblastomas are malignant childhood brain tumors that arise due to the aberrant activity of developmental pathways during postnatal cerebellar development and in adult humans. Transcriptome analysis has identified four major medulloblastoma subgroups. One of them, the Sonic hedgehog (SHH) subgroup, is caused by aberrant Hedgehog signal transduction due to mutations in the Patched1 (PTCH1) receptor or downstream effectors. Mice carrying a Patched-1 null allele (Ptch1∆/+) are a good model to study the alterations underlying medulloblastoma development as a consequence of aberrant Hedgehog pathway activity. Results Transcriptome analysis of human medulloblastomas shows that SERPINE2, also called Protease Nexin-1 (PN-1) is overexpressed in most medulloblastomas, in particular in the SHH and WNT subgroups. As siRNA-mediated lowering of SERPINE2/PN-1 in human medulloblastoma DAOY cells reduces cell proliferation, we analyzed its potential involvement in medulloblastoma development using the Ptch1∆/+ mouse model. In Ptch1∆/+ mice, medulloblastomas arise as a consequence of aberrant Hedgehog pathway activity. Genetic reduction of Serpine2/Pn-1 interferes with medulloblastoma development in Ptch1∆/+ mice, as ~60% of the pre-neoplastic lesions (PNLs) fail to develop into medulloblastomas and remain as small cerebellar nodules. In particular the transcription factor Atoh1, whose expression is essential for development of SHH subgroup medulloblastomas is lost. Comparative molecular analysis reveals the distinct nature of the PNLs in young Ptch1∆/+Pn-1Δ/+ mice. The remaining wild-type Ptch1 allele escapes transcriptional silencing in most cases and the aberrant Hedgehog pathway activity is normalized. Furthermore, cell proliferation and the expression of the cell-cycle regulators Mycn and Cdk6 are significantly reduced in PNLs of Ptch1∆/+Pn-1Δ/+ mice. Conclusions Our analysis provides genetic evidence that aberrant Serpine2/Pn-1 is required for

  1. Uppermost mantle seismic velocity and anisotropy in the Euro-Mediterranean region from Pn and Sn tomography

    Science.gov (United States)

    Díaz, J.; Gil, A.; Gallart, J.

    2013-01-01

    In the last 10-15 years, the number of high quality seismic stations monitoring the Euro-Mediterranean region has increased significantly, allowing a corresponding improvement in structural constraints. We present here new images of the seismic velocity and anisotropy variations in the uppermost mantle beneath this complex area, compiled from inversion of Pn and Sn phases sampling the whole region. The method of Hearn has been applied to the traveltime arrivals of the International Seismological Center catalogue for the time period 1990-2010. A total of 579 753 Pn arrivals coming from 12 377 events recorded at 1 408 stations with epicentral distances between 220 km and 1 400 km have been retained after applying standard quality criteria (maximum depth, minimum number of recordings, maximum residual values …). Our results show significant features well correlated with surface geology and evidence the heterogeneous character of the Euro-Mediterranean lithosphere. The station terms reflect the existence of marked variations in crustal thickness, consistent with available Moho depths inferred from active seismic experiments. The highest Pn velocities are observed along a continuous band from the Po Basin to the northern Ionian Sea. Other high velocity zones include the Ligurian Basin, the Valencia Trough, the southern Alboran Sea and central part of the Algerian margin. Most significant low-velocity values are associated to orogenic belts (Betics, Pyrenees, Alps, Apennines and Calabrian Arc, Dinarides-Hellenides), and low-velocity zones are also identified beneath Sardinia and the Balearic Islands. The introduction of an anisotropic term enhances significantly the lateral continuity of the anomalies, in particular in the most active tectonic areas. Pn anisotropy shows consistent orientations subparallel to major orogenic structures, such as Betics, Apennines, Calabrian Arc and Alps. The Sn tomographic image has lower resolution but confirms independently most of the

  2. GaAs Nanowire pn-Junctions Produced by Low-Cost and High-Throughput Aerotaxy.

    Science.gov (United States)

    Barrigón, E; Hultin, O; Lindgren, D; Yadegari, F; Magnusson, M H; Samuelson, L; Johansson, L I M; Björk, M T

    2018-02-14

    Semiconductor nanowires could significantly boost the functionality and performance of future electronics, light-emitting diodes, and solar cells. However, realizing this potential requires growth methods that enable high-throughput and low-cost production of nanowires with controlled doping. Aerotaxy is an aerosol-based method with extremely high growth rate that does not require a growth substrate, allowing mass-production of high-quality nanowires at a low cost. So far, pn-junctions, a crucial element of solar cells and light-emitting diodes, have not been realized by Aerotaxy growth. Here we report a further development of the Aerotaxy method and demonstrate the growth of GaAs nanowire pn-junctions. Our Aerotaxy system uses an aerosol generator for producing the catalytic seed particles, together with a growth reactor with multiple consecutive chambers for growth of material with different dopants. We show that the produced nanowire pn-junctions have excellent diode characteristics with a rectification ratio of >10 5 , an ideality factor around 2, and very promising photoresponse. Using electron beam induced current and hyperspectral cathodoluminescence, we determined the location of the pn-junction and show that the grown nanowires have high doping levels, as well as electrical properties and diffusion lengths comparable to nanowires grown using metal organic vapor phase epitaxy. Our findings demonstrate that high-quality GaAs nanowire pn-junctions can be produced using a low-cost technique suitable for mass-production, paving the way for industrial-scale production of nanowire-based solar cells.

  3. A P-N Sequence Generator Using LFSR with Dual Edge Trigger Technique

    Directory of Open Access Journals (Sweden)

    Naghwal Nitin Kumar

    2016-01-01

    Full Text Available This paper represents the design and implementation of a low power 4-bit LFSR using Dual edge triggered flip flop. A linear feedback shift register (LFSR is assembled by N number of flip flops connected in series and a combinational logic generally xor gate. An LFSR can generate random number sequence which acts as cipher in cryptography. A known text encrypted over long PN sequence, in order to improve security sequence made longer ie 128 bit; require long chain of flip flop leads to more power consumption. In this paper a novel circuit of random sequence generator using dual edge triggered flip flop has been proposed. Data has been generated on every edge of flip flop instead of single edge. A DETFF-LFSR can generate random number require with less number of clock cycle, it minimizes the number of flip flop result in power saving. In this paper we concentrates on the designing of power competent Test Pattern Generator (TPG using four dual edge triggered flip-flops as the basic building block, overall there is reduction of power around 25% by using these techniques.

  4. UNUSUAL CARBONACEOUS DUST DISTRIBUTION IN PN G095.2+00.7

    Energy Technology Data Exchange (ETDEWEB)

    Ohsawa, Ryou; Onaka, Takashi; Sakon, Itsuki; Mori, Tamami I. [Department of Astronomy, Graduate School of Science, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan); Miyata, Takashi; Asano, Kentaro [Institute of Astronomy, University of Tokyo, 2-21-1 Osawa, Mitaka, Tokyo 181-0015 (Japan); Matsuura, Mikako [Department of Physics and Astronomy, University College London, Kathleen Lonsdale Building, Gower Place, London WC1E 6BT (United Kingdom); Kaneda, Hidehiro, E-mail: ohsawa@astron.s.u-tokyo.ac.jp [Division of Particle and Astrophysical Sciences, G. Nagoya University, Chikusa-ku, Furo-cho, Nagoya 464-8602 (Japan)

    2012-12-01

    We investigate the polycyclic aromatic hydrocarbon (PAH) features in the young Galactic planetary nebula PN G095.2+00.7 based on mid-infrared observations. The near- to mid-infrared spectra obtained with the AKARI/IRC and the Spitzer/IRS show the PAH features as well as the broad emission feature at 12 {mu}m usually seen in proto-planetary nebulae (pPNe). The spatially resolved spectra obtained with Subaru/COMICS suggest that the broad emission around 12 {mu}m is distributed in a shell-like structure, but the unidentified infrared band at 11.3 {mu}m is selectively enhanced at the southern part of the nebula. The variation can be explained by a difference in the amount of the UV radiation to excite PAHs, and does not necessarily require the chemical processing of dust grains and PAHs. It suggests that the UV self-extinction is important to understand the mid-infrared spectral features. We propose a mechanism which accounts for the evolutionary sequence of the mid-infrared dust features seen in a transition from pPNe to PNe.

  5. Pronounced Photovoltaic Response from Multilayered Transition-Metal Dichalcogenides PN-Junctions.

    Science.gov (United States)

    Memaran, Shahriar; Pradhan, Nihar R; Lu, Zhengguang; Rhodes, Daniel; Ludwig, Jonathan; Zhou, Qiong; Ogunsolu, Omotola; Ajayan, Pulickel M; Smirnov, Dmitry; Fernández-Domínguez, Antonio I; García-Vidal, Francisco J; Balicas, Luis

    2015-11-11

    Transition metal dichalcogenides (TMDs) are layered semiconductors with indirect band gaps comparable to Si. These compounds can be grown in large area, while their gap(s) can be tuned by changing their chemical composition or by applying a gate voltage. The experimental evidence collected so far points toward a strong interaction with light, which contrasts with the small photovoltaic efficiencies η ≤ 1% extracted from bulk crystals or exfoliated monolayers. Here, we evaluate the potential of these compounds by studying the photovoltaic response of electrostatically generated PN-junctions composed of approximately 10 atomic layers of MoSe2 stacked onto the dielectric h-BN. In addition to ideal diode-like response, we find that these junctions can yield, under AM-1.5 illumination, photovoltaic efficiencies η exceeding 14%, with fill factors of ~70%. Given the available strategies for increasing η such as gap tuning, improving the quality of the electrical contacts, or the fabrication of tandem cells, our study suggests a remarkable potential for photovoltaic applications based on TMDs.

  6. Room-temperature near-infrared electroluminescence from boron-diffused silicon pn junction diodes

    Directory of Open Access Journals (Sweden)

    Si eLi

    2015-02-01

    Full Text Available Silicon pn junction diodes with different doping concentrations were prepared by boron diffusion into Czochralski (CZ n-type silicon substrate. Their room-temperature near-infrared electroluminescence (EL was measured. In the EL spectra of the heavily boron doped diode, a luminescence peak at ~1.6 m (0.78 eV was observed besides the band-to-band line (~1.1eV under the condition of high current injection, while in that of the lightly boron doped diode only the band-to-band line was observed. The intensity of peak at 0.78 eV increases exponentially with current injection with no observable saturation at room temperature. Furthermore, no dislocations were found in the cross-sectional transmission electron microscopy image, and no dislocation-related luminescence was observed in the low-temperature photoluminescence spectra. We deduce the 0.78 eV emission originates from the irradiative recombination in the strain region of diodes caused by the diffusion of large number of boron atoms into silicon crystal lattice.

  7. Polaron absorption for photovoltaic energy conversion in a manganite-titanate pn heterojunction

    Science.gov (United States)

    Saucke, Gesine; Norpoth, Jonas; Jooss, Christian; Su, Dong; Zhu, Yimei

    2012-04-01

    The relation among structure, electric transport, and photovoltaic effect is investigated for a pn heterojunction with strong correlation interactions. A perovskite interface is chosen as a model system consisting of the p-doped strongly correlated manganite Pr0.64Ca0.36MnO3 (PCMO) and the n-doped titanate SrTi1-yNbyO3 (y=0.002 and 0.01). High-resolution electron microscopy and spectroscopy reveal a nearly dislocation-free, epitaxial interface and give insight into the local atomic and electronic structure. The presence of a photovoltaic effect under visible light at room temperature suggests the existence of mobile excited polarons within the band-gap-free PCMO absorber. The temperature-dependent rectifying current-voltage characteristics prove to be mainly determined by the presence of an interfacial energy spike in the conduction band and are affected by the colossal electroresistance effect. From the comparison of photocurrents and spatiotemporal distributions of photogenerated carriers (deduced from optical absorption spectroscopy), we discuss the range of the excited polaron diffusion length.

  8. Tuning a circular p-n junction in graphene from quantum confinement to optical guiding

    Science.gov (United States)

    Jiang, Yuhang; Mao, Jinhai; Moldovan, Dean; Masir, Massoud Ramezani; Li, Guohong; Watanabe, Kenji; Taniguchi, Takashi; Peeters, Francois M.; Andrei, Eva Y.

    2017-11-01

    The photon-like propagation of the Dirac electrons in graphene, together with its record-high electronic mobility, can lead to applications based on ultrafast electronic response and low dissipation. However, the chiral nature of the charge carriers that is responsible for the high mobility also makes it difficult to control their motion and prevents electronic switching. Here, we show how to manipulate the charge carriers by using a circular p-n junction whose size can be continuously tuned from the nanometre to the micrometre scale. The junction size is controlled with a dual-gate device consisting of a planar back gate and a point-like top gate made by decorating a scanning tunnelling microscope tip with a gold nanowire. The nanometre-scale junction is defined by a deep potential well created by the tip-induced charge. It traps the Dirac electrons in quantum-confined states, which are the graphene equivalent of the atomic collapse states (ACSs) predicted to occur at supercritically charged nuclei. As the junction size increases, the transition to the optical regime is signalled by the emergence of whispering-gallery modes, similar to those observed at the perimeter of acoustic or optical resonators, and by the appearance of a Fabry-Pérot interference pattern for junctions close to a boundary.

  9. Optimization and modeling of avalanche photodiode structures - Application to a new class of superlattice photodetectors, the p-i-n, p-n homojunction, and p-n heterojunction APD's

    Science.gov (United States)

    Brennan, Kevin F.

    1987-08-01

    A general device model is used to optimize designs for three superlattice device avalanche photodiodes (APDs), the p-i-n, p-n homojunction, and p-n heterojunction devices. The gain, excess noise factor, bandwidth, and gain-bandwidth product are calculated in a first principles Monte Carlo investigation of the impact ionization probabilities of the electrons and holes. The performances of the three APDs are analyzed in the context of lightwave communications systems (where high gain at low noise and large bandwidth are the most critical performance criteria) and in digital applications (where devices must operate at or below 5V, in addition to providing gain at low internal noise and at large bandwidth).

  10. Transition region width of nanowire hetero- and pn-junctions grown using vapor-liquid-solid processes

    Science.gov (United States)

    Li, Na; Tan, Teh Y.; Gösele, U.

    2008-03-01

    The transition region width of nanowire heterojunctions and pn-junctions grown using vapor-liquid-solid (VLS) processes has been modeled. With two constituents or dopants I and II, the achievable width or abruptness of the junctions is attributed to the residual I atom/molecule stored in the liquid droplet at the onset of introducing II to grow the junction, and the stored I atom/molecule consumption into the subsequently grown crystal layers. The model yields satisfactory quantitative fits to a set of available Si-Ge junction data. Moreover, the model provides a satisfactory explanation to the relative junction width or abruptness differences between elemental and compound semiconductor junction cases, as well as a guideline for achieving the most desirable pn-junction widths.

  11. Mapping electrostatic profiles across axial p-n junctions in Si nanowires using off-axis electron holography

    Science.gov (United States)

    Gan, Zhaofeng; Perea, Daniel E.; Yoo, Jinkyoung; Tom Picraux, S.; Smith, David J.; McCartney, Martha R.

    2013-10-01

    Si nanowires (NWs) with axial p-n junctions were grown by the vapor-liquid-solid method. Transmission electron microscopy and electron holography were used to characterize the microstructure and electrostatic properties. Measurement of the potential profile showed the presence of a p-n junction with a height of 1.0 ± 0.3 V. A Schottky barrier was observed at the end of the NW due to the Au catalyst particle. Comparison with simulations indicated dopant concentrations of 1019 cm-3 for donors and 1017 cm-3 for acceptors. These results confirm the benefit of combining off-axis electron holography with simulations for determining localized information about the electrically active dopant distributions in nanowire structures.

  12. Mapping Electrostatic Profiles Across Axial p-n Junctions in Si Nanowires using Off-Axis Electron Holography

    Energy Technology Data Exchange (ETDEWEB)

    Gan, Zhaofeng; Perea, Daniel E.; Yoo, Jinkyoung; Picraux, Samuel T.; Smith, David J.; Mccartney, Martha R.

    2013-10-07

    Si nanowires (NWs) with axial p-n junctions were grown by the vapor-liquid-solid method. Transmission electron microscopy and electron holography were used to characterize the microstructure and electrostatic properties. Measurement of the potential profile showed the presence of a p-n junction with a height of 1.0±0.3V. A Schottky barrier was observed at the end of the NW due to the Au catalyst particle. Comparison with simulations indicated dopant concentrations of 1019cm-3 for donors and 1017cm-3 for acceptors. These results confirm the benefit of combining off-axis electron holography with simulations for determining localized information about the electrically active dopant distributions in nanowire structures.

  13. Least-Squares PN Formulation of the Transport Equation Using Self-Adjoint-Angular-Flux Consistent Boundary Conditions

    Energy Technology Data Exchange (ETDEWEB)

    Laboure, Vincent M.; Wang, Yaqi; DeHart, Mark D.

    2016-05-01

    In this paper, we study the Least-Squares (LS) PN form of the transport equation compatible with voids [1] in the context of Continuous Finite Element Methods (CFEM).We first deriveweakly imposed boundary conditions which make the LS weak formulation equivalent to the Self-Adjoint Angular Flux (SAAF) variational formulation with a void treatment [2], in the particular case of constant cross-sections and a uniform mesh. We then implement this method in Rattlesnake with the Multiphysics Object Oriented Simulation Environment (MOOSE) framework [3] using a spherical harmonics (PN) expansion to discretize in angle. We test our implementation using the Method of Manufactured Solutions (MMS) and find the expected convergence behavior both in angle and space. Lastly, we investigate the impact of the global non-conservation of LS by comparing the method with SAAF on a heterogeneous test problem.

  14. Least-Squares PN Formulation of the Transport Equation Using Self-Adjoint-Angular-Flux Consistent Boundary Conditions.

    Energy Technology Data Exchange (ETDEWEB)

    Vincent M. Laboure; Yaqi Wang; Mark D. DeHart

    2016-05-01

    In this paper, we study the Least-Squares (LS) PN form of the transport equation compatible with voids in the context of Continuous Finite Element Methods (CFEM).We first deriveweakly imposed boundary conditions which make the LS weak formulation equivalent to the Self-Adjoint Angular Flux (SAAF) variational formulation with a void treatment, in the particular case of constant cross-sections and a uniform mesh. We then implement this method in Rattlesnake with the Multiphysics Object Oriented Simulation Environment (MOOSE) framework using a spherical harmonics (PN) expansion to discretize in angle. We test our implementation using the Method of Manufactured Solutions (MMS) and find the expected convergence behavior both in angle and space. Lastly, we investigate the impact of the global non-conservation of LS by comparing the method with SAAF on a heterogeneous test problem.

  15. Electrical characterization of ZnO/NiO p-n junction prepared by the sol-gel method

    Science.gov (United States)

    Merih Akyuzlu, A.; Dagdelen, Fethi; Gultek, Ahmet; Hendi, A. A.; Yakuphanoglu, Fahrettin

    2017-04-01

    ZnO and NiO films were synthesized on fluourine-doped tin oxide (FTO) glass substrate by the sol-gel method. The surface morphology of the films was investigated by atomic force microscopy. The optical band gaps of the ZnO and NiO films were found to be 3.198 and 3.827eV, respectively. A ZnO/NiO p-n junction diode was prepared and electrical charge transport mechanism of the diode was analyzed using thermionic emission and Norde functions. The ideality factor, barrier height and series resistance of the diode were determined to be 6.46, 1.036eV and 39.1 M {Ω} , respectively. The obtained results indicate that ZnO/NiO p-n junction can be used as transparent diode for optic communications.

  16. Electrolysis as a controllable method for establishing p-n junctions in multi-nanolayer films of amorphous selenium

    Science.gov (United States)

    John, Joshua D.; Saito, Ichitaro; Ochiai, Jun; Toyama, Ryo; Masuzawa, Tomoaki; Yamada, Takatoshi; Chua, Daniel H. C.; Okano, Ken

    2017-08-01

    We present a controllable way of establishing a p-n junction in amorphous selenium (a-Se) using electrolysis. Amorphous selenium is used as an anode in the electrolysis of NaCl solution. By varying the duration of the electrolysis, we can make the contact to a-Se either Ohmic or rectifying and control the built-in potential and full depletion voltage of the contacts and junctions formed in the a-Se. I-V and C-V measurements show that after electrolysis rectification occurs and that as the duration of electrolysis increases, the direction of rectification changes, with the magnitudes of the built-in potential and the full depletion becoming higher. From the results, we present a model for the electrochemical process of forming the p-n junction and highlight the dependence on the duration of the electrolysis.

  17. Diffused junction p(+)-n solar cells in bulk GaAs. II - Device characterization and modelling

    Science.gov (United States)

    Keeney, R.; Sundaram, L. M. G.; Rode, H.; Bhat, I.; Ghandhi, S. K.; Borrego, J. M.

    1984-01-01

    The photovoltaic characteristics of p(+)-n junction solar cells fabricated on bulk GaAs by an open tube diffusion technique are presented in detail. Quantum efficiency measurements were analyzed and compared to computer simulations of the cell structure in order to determine material parameters such as diffusion length, surface recombination velocity and junction depth. From the results obtained it is projected that proper optimization of the cell parameters can increase the efficiency of the cells to close to 20 percent.

  18. Frequency-Dependent Nature of Pn in Western China: Gaussian Beam Modeling of Data from the Hi-CLIMB Experiment

    Science.gov (United States)

    2008-09-30

    with respect to depth below the Moho interface (Cerveny and Ravindra, 1971; Hill, 1971; Menke and Richards, 1980). These interfering waves can simply...the Moho can affect the propagation of Pn. A) The model for P-wave speeds. The linear gradient beneath the Moho can simply arise from the spherical...nature of the earth. B) Paths of the primary, diving rays (pure head waves are not shown). C) Paths of the first set of sub- Moho interference wave. D

  19. Direct determination of minority carrier diffusion lengths at axial GaAs nanowire p-n junctions.

    Science.gov (United States)

    Gutsche, Christoph; Niepelt, Raphael; Gnauck, Martin; Lysov, Andrey; Prost, Werner; Ronning, Carsten; Tegude, Franz-Josef

    2012-03-14

    Axial GaAs nanowire p-n diodes, possibly one of the core elements of future nanowire solar cells and light emitters, were grown via the Au-assisted vapor-liquid-solid mode, contacted by electron beam lithography, and investigated using electron beam induced current measurements. The minority carrier diffusion lengths and dynamics of both, electrons and holes, were determined directly at the vicinity of the p-n junction. The generated photocurrent shows an exponential decay on both sides of the junction and the extracted diffusion lengths are about 1 order of magnitude lower compared to bulk material due to surface recombination. Moreover, the observed strong diameter-dependence is well in line with the surface-to-volume ratio of semiconductor nanowires. Estimating the surface recombination velocities clearly indicates a nonabrupt p-n junction, which is in essential agreement with the model of delayed dopant incorporation in the Au-assisted vapor-liquid-solid mechanism. Surface passivation using ammonium sulfide effectively reduces the surface recombination and thus leads to higher minority carrier diffusion lengths. © 2012 American Chemical Society

  20. Chemically fixed p-n heterojunctions for polymer electronics by means of covalent B-F bond formation.

    Science.gov (United States)

    Hoven, Corey V; Wang, Huiping; Elbing, Mark; Garner, Logan; Winkelhaus, Daniel; Bazan, Guillermo C

    2010-03-01

    Widely used solid-state devices fabricated with inorganic semiconductors, including light-emitting diodes and solar cells, derive much of their function from the p-n junction. Such junctions lead to diode characteristics and are attained when p-doped and n-doped materials come into contact with each other. Achieving bilayer p-n junctions with semiconducting polymers has been hindered by difficulties in the deposition of thin films with independent p-doped and n-doped layers. Here we report on how to achieve permanently fixed organic p-n heterojunctions by using a cationic conjugated polyelectrolyte with fluoride counteranions and an underlayer composed of a neutral conjugated polymer bearing anion-trapping functional groups. Application of a bias leads to charge injection and fluoride migration into the neutral layer, where irreversible covalent bond formation takes place. After the initial charging and doping, one obtains devices with no delay in the turn on of light-emitting electrochemical behaviour and excellent current rectification. Such devices highlight how mobile ions in organic media can open opportunities to realize device structures in ways that do not have analogies in the world of silicon and promise new opportunities for integrating organic materials within technologies now dominated by inorganic semiconductors.

  1. A new pnCCD-based color X-ray camera for fast spatial and energy-resolved measurements

    Energy Technology Data Exchange (ETDEWEB)

    Ordavo, I., E-mail: ivan.ordavo@pnsensor.de [PNSensor GmbH, Roemerstrasse 28, 80803 Muenchen (Germany); PNDetector GmbH, Emil-Nolde-Strasse 10, 81735 Muenchen (Germany); Ihle, S. [PNSensor GmbH, Roemerstrasse 28, 80803 Muenchen (Germany); Arkadiev, V. [Institut fuer angewandte Photonik e.V., Rudower Chaussee 29/31, 12489 Berlin (Germany); Scharf, O. [BAM Federal Institute for Materials Research and Testing, Richard-Willstaetter-Strasse 11, 12489 Berlin (Germany); Soltau, H. [PNSensor GmbH, Roemerstrasse 28, 80803 Muenchen (Germany); Bjeoumikhov, A.; Bjeoumikhova, S. [IFG - Institute for Scientific Instruments GmbH, Rudower Chaussee 29/31, 12489 Berlin (Germany); Buzanich, G. [BAM Federal Institute for Materials Research and Testing, Richard-Willstaetter-Strasse 11, 12489 Berlin (Germany); Gubzhokov, R.; Guenther, A. [IFG - Institute for Scientific Instruments GmbH, Rudower Chaussee 29/31, 12489 Berlin (Germany); Hartmann, R.; Holl, P. [PNSensor GmbH, Roemerstrasse 28, 80803 Muenchen (Germany); Kimmel, N. [Max-Planck-Institut fuer extraterrestrische Physik, Giessenbachstrasse, 85748 Garching (Germany); Max-Planck-Institut Halbleiterlabor, Otto-Hahn-Ring 6, 81739 Muenchen (Germany); Kuehbacher, M. [Helmholtz Centre Berlin for Materials and Energy, Hahn-Meitner-Platz 1, 14109 Berlin (Germany); Lang, M. [PNSensor GmbH, Roemerstrasse 28, 80803 Muenchen (Germany); Langhoff, N. [IFG - Institute for Scientific Instruments GmbH, Rudower Chaussee 29/31, 12489 Berlin (Germany); Liebel, A. [PNDetector GmbH, Emil-Nolde-Strasse 10, 81735 Muenchen (Germany); Radtke, M.; Reinholz, U.; Riesemeier, H. [BAM Federal Institute for Materials Research and Testing, Richard-Willstaetter-Strasse 11, 12489 Berlin (Germany); and others

    2011-10-21

    We present a new high resolution X-ray imager based on a pnCCD detector and a polycapillary optics. The properties of the pnCCD like high quantum efficiency, high energy resolution and radiation hardness are maintained, while color corrected polycapillary lenses are used to direct the fluorescence photons from every spot on a sample to a corresponding pixel on the detector. The camera is sensitive to photons from 3 to 40 keV with still 30% quantum efficiency at 20 keV. The pnCCD is operated in split frame mode allowing a high frame rate of 400 Hz with an energy resolution of 152 eV for Mn K{alpha} (5.9 keV) at 450 kcps. In single-photon counting mode (SPC), the time, energy and position of every fluorescence photon is recorded for every frame. A dedicated software enables the visualization of the elements distribution in real time without the need of post-processing the data. A description of the key components including detector, X-ray optics and camera is given. First experiments show the capability of the camera to perform fast full-field X-Ray Fluorescence (FF-XRF) for element analysis. The imaging performance with a magnifying optics (3x) has also been successfully tested.

  2. Single Atomically Sharp Lateral Monolayer p-n Heterojunction Solar Cells with Extraordinarily High Power Conversion Efficiency.

    Science.gov (United States)

    Tsai, Meng-Lin; Li, Ming-Yang; Retamal, José Ramón Durán; Lam, Kai-Tak; Lin, Yung-Chang; Suenaga, Kazu; Chen, Lih-Juann; Liang, Gengchiau; Li, Lain-Jong; He, Jr-Hau

    2017-08-01

    The recent development of 2D monolayer lateral semiconductor has created new paradigm to develop p-n heterojunctions. Albeit, the growth methods of these heterostructures typically result in alloy structures at the interface, limiting the development for high-efficiency photovoltaic (PV) devices. Here, the PV properties of sequentially grown alloy-free 2D monolayer WSe2 -MoS2 lateral p-n heterojunction are explores. The PV devices show an extraordinary power conversion efficiency of 2.56% under AM 1.5G illumination. The large surface active area enables the full exposure of the depletion region, leading to excellent omnidirectional light harvesting characteristic with only 5% reduction of efficiency at incident angles up to 75°. Modeling studies demonstrate the PV devices comply with typical principles, increasing the feasibility for further development. Furthermore, the appropriate electrode-spacing design can lead to environment-independent PV properties. These robust PV properties deriving from the atomically sharp lateral p-n interface can help develop the next-generation photovoltaics. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Single Atomically Sharp Lateral Monolayer p-n Heterojunction Solar Cells with Extraordinarily High Power Conversion Efficiency

    KAUST Repository

    Tsai, Meng-Lin

    2017-06-26

    The recent development of 2D monolayer lateral semiconductor has created new paradigm to develop p-n heterojunctions. Albeit, the growth methods of these heterostructures typically result in alloy structures at the interface, limiting the development for high-efficiency photovoltaic (PV) devices. Here, the PV properties of sequentially grown alloy-free 2D monolayer WSe-MoS lateral p-n heterojunction are explores. The PV devices show an extraordinary power conversion efficiency of 2.56% under AM 1.5G illumination. The large surface active area enables the full exposure of the depletion region, leading to excellent omnidirectional light harvesting characteristic with only 5% reduction of efficiency at incident angles up to 75°. Modeling studies demonstrate the PV devices comply with typical principles, increasing the feasibility for further development. Furthermore, the appropriate electrode-spacing design can lead to environment-independent PV properties. These robust PV properties deriving from the atomically sharp lateral p-n interface can help develop the next-generation photovoltaics.

  4. Integrated Advanced Microwave Sounding Unit-A (AMSU-A). Performance Verification Report: METSAT (S/N) AMSU-A1 Receiver Assemblies P/N 1356429-1 S/N F06 and P/N 1356409-1 S/N F06

    Science.gov (United States)

    1999-01-01

    This is the Performance Verification Report, METSAT (S/N 109) AMSU-A1 Receiver Assemblies, P/N 1356429-1 S/N F06 and P/N 1356409 S/N F06, for the Integrated Advanced Microwave Sounding Unit-A (AMSU-A).

  5. Energy dependent charge spread function in a dedicated synchrotron beam pnCCD detector

    Energy Technology Data Exchange (ETDEWEB)

    Yousef, Hazem

    2011-05-20

    A scan on the pixel edges is the method which is used to resolve the electron cloud size in the pixel array of the pnCCD detector. The EDR synchrotron radiation in BESSY is the source of the X-ray photons which are used in the scans. The radius of the electron cloud as a function of the impinging photon energy is analyzed. The angle of incidence of the X-ray beam is employed in the measurements. The measurements are validated by the numerical simulation models. The inclined X-ray track leads to distribute the electron clouds in a certain number of pixels according to the incident angle of the X-ray beam. The pixels detect different electron clouds according to their generation position in the detector bulk. A collimated X-ray beam of 12.14 keV is used in the measurements with 30 and 40 entrance angles. It is shown that the two factors that leads to expand the electron clouds namely the diffusion and the mutual electrostatic repulsion can be separated from the measured electron clouds. It is noticed as well that the influence of the mutual electrostatic repulsion dominates the cloud expansion over the diffusion process in the collection time of the detector. The perpendicular X-ray track leads to determine the average radius of the electron cloud per photon energy. The results show that the size of the electron clouds (RMS) in the energy range of [5.0-21.6] keV is smaller than the pixel size. (orig.)

  6. Integrated Advanced Microwave Sounding Unit-A (AMSU-A). Performance Verification Report: Antenna Drive Subsystem METSAT AMSU-A2 (PN:1331200-2, SN:108)

    Science.gov (United States)

    Haapala, C.

    1999-01-01

    This is the Performance Verification Report, Antenna Drive Subassembly, Antenna Drive Subsystem, METSAT AMSU-A2 (P/N 1331200-2, SN: 108), for the Integrated Advanced Microwave Sounding Unit-A (AMSU-A).

  7. Separation of Flip and Non-Flip parst of Charge Exchange np->pn at energies Tn = 0.5 - 2.0 GeV

    CERN Document Server

    Shindin, R A; Chernykh, E V; Guriev, D K; Nomofilov, A A; Prytkov, V Yu; Sharov, V I; Strunov, L I

    2008-01-01

    The new Delta-Sigma experimental data on the ratio $R_{dp}$ allowed separating the Flip and Non-Flip parts of the differential cross section of $np\\to pn$ charge exchange process at the zero angle by the Dean formula. The PSA solutions for the $np\\to np$ elastic scattering are transformed to the $np\\to pn$ charge exchange representation using unitary transition, and good agreement is obtain.

  8. Hybrid pn-junction solar cells based on layers of inorganic nanocrystals and organic semiconductors: optimization of layer thickness by considering the width of the depletion region.

    Science.gov (United States)

    Saha, Sudip K; Guchhait, Asim; Pal, Amlan J

    2014-03-07

    We report the formation and characterization of hybrid pn-junction solar cells based on a layer of copper diffused silver indium disulfide (AgInS2@Cu) nanoparticles and another layer of copper phthalocyanine (CuPc) molecules. With copper diffusion in the nanocrystals, their optical absorption and hence the activity of the hybrid pn-junction solar cells was extended towards the near-IR region. To decrease the particle-to-particle separation for improved carrier transport through the inorganic layer, we replaced the long-chain ligands of copper-diffused nanocrystals in each monolayer with short-ones. Under illumination, the hybrid pn-junctions yielded a higher short-circuit current as compared to the combined contribution of the Schottky junctions based on the components. A wider depletion region at the interface between the two active layers in the pn-junction device as compared to that of the Schottky junctions has been considered to analyze the results. Capacitance-voltage characteristics under a dark condition supported such a hypothesis. We also determined the width of the depletion region in the two layers separately so that a pn-junction could be formed with a tailored thickness of the two materials. Such a "fully-depleted" device resulted in an improved photovoltaic performance, primarily due to lessening of the internal resistance of the hybrid pn-junction solar cells.

  9. Ethylene polymerization by PN3-type pincer chromium(III) complexes

    KAUST Repository

    Gong, Dirong

    2014-12-01

    Chromium (III) complexes, Cr1, [2,6-(tBu2PNH) 2C5H4N]CrCl3; Cr2, [2,6-(Ph 2PNH)2C5H4N]CrCl3; Cr3, [2-(tBu2PNH)C5H4N]CrCl3 THF; Cr4, [6-(tBu2PNH)C5H4N-2- CH2NEt2]CrCl3; Cr5, [6-(tBu 2PNH)C5H4N-2-C3H2N 2]CrCl3; Cr6, [6-(tBu2PNH)C 5H4N-2-(3,5-Me2)C3H 2N2]CrCl3; Cr7, [6-(tBu 2PNH)C5H4N-2-(3,5-iPr 2)C3H2N2]CrCl3; Cr8, [6-(tBu2PNH)C5H4N-2-(3,5-Ph 2)C3H2N2]CrCl3, bearing a family of neutral PN3-type pincer ligands have been prepared. The molecular structure of Cr2 was further elucidated by the X-ray crystallographic analysis, showing an octahedral geometry. Treatment of these complexes with MAO or alkylaluminum led to catalysts with moderate activities (about 105 g (PE)/Cr(mol) h) for ethylene polymerization, affording exclusively linear low molecular weight solid PE without any detectable oligomers. Among Cr1-Cr8, the highest activity was achieved for Cr1/MAO at room temperature with production of PE with highest molecular weight, indicating that replacement of both tBu groups in Cr1 with Ph groups, or one PtBu2 with the N (imine) arm, resulted in a lower catalytic activity and lower M w. © 2014 Elsevier B.V.

  10. Hydrogen Passivation of N(+)P and P(+)N Heteroepitaxial InP Solar Cell Structures

    Science.gov (United States)

    Chatterjee, B.; Davis, W. C.; Ringel, S. A.; Hoffman, R., Jr.

    1995-01-01

    Dislocations and related point defect complexes caused by lattice mismatch currently limit the performance of heteroepitaxial InP cells by introducing shunting paths across the active junction and by the formation of deep traps within the base region. We have previously demonstrated that plasma hydrogenation is an effective and stable means to passivate the electrical activity of such defects in specially designed heteroepitaxial InP test structures to probe hydrogen passivation at typical base depths within a cell structure. In this work, we present our results on the hydrogen passivation of actual heteroepitaxial n(+)p and p(+)n InP cell structures grown on GaAs substrates by metalorganic chemical vapor deposition (MOCVD). We have found that a 2 hour exposure to a 13.56 MHz hydrogen plasma at 275 C reduces the deep level concentration in the base regions of both n(+)p and p(+)n heteroepitaxial InP cell structures from as-grown values of 5 - 7 x 10(exp 14)/cc, down to 3 - 5 x 10(exp 12)/cc. All dopants were successfully reactivated by a 400 C, 5 minute anneal With no detectable activation of deep levels. I-V analysis indicated a subsequent approx. 100 fold decrease In reverse leakage current at -1 volt reverse bias, and an improved built in voltage for the p(+)n structures. ln addition to being passivated,dislocations are also shown to participate in secondary interactions during hydrogenation. We find that the presence of dislocations enhances hydrogen diffusion into the cell structure, and lowers the apparent dissociation energy of Zn-H complexes from 1.19 eV for homoepitaxial Zn-doped InP to 1.12 eV for heteroepitaxial Zn-doped InP. This is explained by additional hydrogen trapping at dislocations subsequent to the reactivation of Zn dopants after hydrogenation.

  11. Hydrogen passivation of N(+)-P and P(+)-N heteroepitaxial InP solar cell structures

    Science.gov (United States)

    Chatterjee, Basab; Davis, William C.; Ringel, Steve A.; Hoffman, Richard, Jr.

    1996-01-01

    Dislocations and related point defect complexes caused by lattice mismatch currently limit the performance of heteroepitaxial InP cells by introducing shunting paths across the active junction and by the formation of deep traps within the base region. We have previously demonstrated that plasma hydrogenation is an effective and stable means to passivate the electrical activity of such defects in specially designed heteroepitaxial InP test structures to probe hydrogen passivation at typical base depths within a cell structure. In this work, we present our results on the hydrogen passivation of actual heteroepitaxial n-p and p-n InP cell structures grown on GaAs substrates by metalorganic chemical vapor deposition (MOCVD). We have found that a 2 hour exposure to a 13.56 MHz hydrogen plasma at 275 C reduces the deep level concentration in the base regions of both n(+)-p and p(+)-n heteroepitaxial InP cell structures from as-grown values of 5-7 x 10(exp 14) cm(exp -3), down to 3-5 x 10(exp 12) cm(exp -3). All dopants were successfully reactivated by a 400 C, 5 minute anneal with no detectable activation of deep levels. One to five analysis indicated a subsequent approximately 100 fold decrease in reverse leakage current at -1 volt reverse bias, and an improved built in voltage for the p(+)-n structures. In addition to being passivated, dislocations are also shown to participate in secondary interactions during hydrogenation. We find that the presence of dislocations enhances hydrogen diffusion into the cell structure, and lowers the apparent dissociation energy of Zn-H complexes from 1.19 eV for homoepitaxial Zn-doped InP to 1.12 eV for heteroepitaxial Zn-doped InP. This is explained by additional hydrogen trapping at dislocations subsequent to the reactivation of Zn dopants after hydrogenation.

  12. Simulating and modeling the breakdown voltage in a semi-insulating GaAs P+N junction diode

    Science.gov (United States)

    Resfa, A.; Menezla, Brahimi. R.; Benchhima, M.

    2014-08-01

    This work aims to determine the characteristic I (breakdown voltage) of the inverse current in a GaAs PN junction diode, subject to a reverse polarization, while specifying the parameters that influence the breakdown voltage of the diode. In this work, we simulated the behavior of the ionization phenomenon by impact breakdown by avalanche of the PN junctions, subject to an inverse polarization. We will take into account both the trapping model in a stationary regime in the P+N structure using like material of basis the III-V compounds and mainly the GaAs semi-insulating in which the deep centers have in important densities. We are talking about the model of trapping in the space charge region (SCR) and that is the trap density donor and acceptor states. The carrier crossing the space charge region (SCR) of W thickness creates N electron—hole pairs: for every created pair, the electron and the hole are swept quickly by the electric field, each in an opposite direction, which comes back, according to an already accepted reasoning, to the crossing of the space charge region (SCR) by an electron or a hole. So the even N pair created by the initial particle provoke N2 ionizations and so forth. The study of the physical and electrical behaviour of semiconductors is based on the influence of the presence of deep centers on the characteristic I(V) current-tension, which requires the calculation of the electrostatic potential, the electric field, the integral of ionization, the density of the states traps, the diffusion current of minority in the regions (1) and (3), the current thermal generation in the region (2), the leakage current in the surface, and the breakdown voltage.

  13. Gamow-Teller strength in deformed nuclei within self-consistent pnQRPA with the Gogny force

    Directory of Open Access Journals (Sweden)

    Martini M.

    2014-03-01

    Full Text Available In recent years fully consistent quasiparticle random-phase approximation (QRPA calculations using finite range Gogny force have been performed to study electromagnetic excitations of several axially-symmetric deformed nuclei up to the 238U. Here we present the extension of this approach to the charge-exchange nuclear excitations (pn-QRPA. In particular we focus on the Gamow-Teller (GT excitations. A comparison of the predicted GT strength distribution with existing experimental data is presented The role of nuclear deformation is shown. Special attention is paid to β-decay half-lives calculations for which experimental data exist.

  14. Growth, electrical rectification, and gate control in axial in situ doped p-n junction germanium nanowires

    Science.gov (United States)

    Le, Son T.; Jannaty, P.; Zaslavsky, A.; Dayeh, S. A.; Picraux, S. T.

    2010-06-01

    We report on vapor-liquid-solid growth and electrical properties of axial in situ doped p-n junction Ge sub-100 nm diameter nanowires. Room temperature four-point measurements show current rectification of two to three orders of magnitude depending on nanowire doping and diameter. We observe strong backgate control of reverse-bias current of up to three orders of magnitude and explain it by band-to-band tunneling modulated by the backgate-controlled electric field, as confirmed qualitatively via a quasi-three-dimensional Schrödinger-Poisson simulation.

  15. Novel InGaAsN pn Junction for High-Efficiency Multiple-Junction Solar Cells

    Energy Technology Data Exchange (ETDEWEB)

    Allerman, A.A.; Chang, P.C.; Gee, J.M.; Hammons, B.E.; Hou, H.Q.; Jones, E.D.; Kurtz, S.R.; Reinhardt, K.C.

    1999-03-26

    We report the application of a novel material, InGaAsN, with bandgap energy of 1.05 eV as a junction in an InGaP/GaAs/InGaAsN/Ge 4-junction design. Results of the growth and structural, optical, and electrical properties were demonstrated, showing the promising perspective of this material for ultra high efficiency solar cells. Photovoltaic properties of an as-grown pn diode structure and improvement through post growth annealing were also discussed.

  16. Design and development of quasi-monoenergetic neutron source using the inverse kinematics of (p,n) reaction

    Energy Technology Data Exchange (ETDEWEB)

    Matsuoka, Y.; Watanabe, Y.; Hachiya, S.; Nakamura, H.; Tanaka, Y. [Kyushu Univ., Department of Advanced Energy Engineering and Science, Kasuga, Fukuoka (Japan); Ikeda, N.; Sagara, K. [Kyushu Univ., Fukuoka (Japan). Dept. of Physics

    2000-03-01

    We has started to develop a new quasi-monoenergetic neutron source using the inverse kinematics of (p,n) reaction at Kyushu University Tandem Laboratory. A preliminary experiment was performed for a neutron source using the {sup 1}H({sup 13}C,n){sup 13}N reaction at an incident energy of 59.3 MeV. It was experimentally observed that monoenergetic neutrons with about 7 MeV were produced at 0deg in the laboratory system and the produced neutrons were collimated to a forward cone restricted by the kinematics. (author)

  17. Single-Crystal N-polar GaN p-n Diodes by Plasma-Assisted Molecular Beam Epitaxy

    OpenAIRE

    Cho, Yongjin; Hu, Zongyang; Nomoto, Kazuki; Xing, Huili Grace; Jena, Debdeep

    2017-01-01

    N-polar GaN p-n diodes are realized on single-crystal N-polar GaN bulk wafers by plasma-assisted molecular beam epitaxy growth. The current-voltage characteristics show high-quality rectification and electroluminescence characteristics with a high on/off current ratio and interband photon emission. The measured electroluminescence spectrum is dominated by strong near-band edge emission, while deep level luminescence is greatly suppressed. A very low dislocation density leads to a high reverse...

  18. Hybrid van der Waals p-n Heterojunctions based on SnO and 2D MoS2

    KAUST Repository

    Wang, Zhenwei

    2016-08-30

    A p-type oxide/2D hybrid van der Waals p-n heterojunction is demonstrated for the first time between SnO (tin monoxide) (the p-type oxide) and 2D MoS2 (molybdenum disulfide), showing an ideality factor of 2 and rectification ratio up to 10(4) . The reported heterojunction is gate-tunable with typical anti-ambipolar transfer characteristics. Surface potential mapping is performed and a current model for such a heterojunction is proposed.

  19. N.G. Basov and early works on semiconductor lasers at P.N. Lebedev Physics Institute

    Energy Technology Data Exchange (ETDEWEB)

    Eliseev, P G [Centre for High-Technology Materials, University of New Mexico, Albuquerque (United States)

    2012-12-31

    A survey is presented of works on creation and investigation of semiconductor lasers during 1957 - 1977 at the P.N. Lebedev Physics Institute. Many of these works were initiated by N.G. Basov, starting from pre-laser time, when N.G. Basov and his coworkers formulated principal conditions of creation of lasers on interband transitions in semiconductors. Main directions of further works were diode lasers based on various materials and structures, their characteristics of output power, high-speed operation and reliability. (special issue devoted to the 90th anniversary of n.g. basov)

  20. Increased cavernosal relaxation by Phoneutria nigriventer toxin, PnTx2-6, via activation at NO/cGMP signaling

    Science.gov (United States)

    Nunes, K.P.; Wynne, B.M.; Cordeiro, M.N.; Borges, M.H.; Richardson, M; Leite, R.; DeLima, M.E.; Webb, R. C

    2011-01-01

    Erectile dysfunction mechanisms in diabetic patients are multifactorial and often lead to resistance to current therapy. Animal toxins have been used as pharmacological tools to study penile erection. Human accidents involving the venom of Phoneutria nigriventer spider are characterized by priapism. We hypothesize that PnTx2-6 potentiates cavernosal relaxation in diabetic mice by increasing cGMP. This effect is nNOS dependent. Cavernosal strips were contracted with phenylephrine (10−5 M) and relaxed by electrical field stimulation (EFS, 20V, 1–32 Hz) in the presence or absence of PnTx2-6 (10−8 M).Cavernosal strips from nNOS and eNOS knocaut (KO) mice, besides nNOS inhibitor (10−5M), were used to evaluate the role of this enzyme in the potentiation effect evoked by PnTx2-6. Tissue cGMP levels were determined after stimulation with PnTx2-6 in presence or absence of L-NAME (10−4M) and ω-conotoxin GVIA (10−6M), an N-type calcium channel inhibitor. Results showed PnTx2-6 enhanced cavernosal relaxation in diabetic mice (65%) and eNOS KO mice, but not in nNOS KO mice. The toxin effect in the cavernosal relaxation was abolished by nNOS inhibitor. cGMP levels are increased by PnTx2-6, however L-NAME abolished this enhancement as well as ω-conotoxin GVIA. We conclude PnTx2-6 facilitates penile relaxation in diabetic mice through a mechanism dependent on nNOS, probably via increasing NO/cGMP production. PMID:21975567

  1. 210Po and 210Pb disequilibrium at the PN section in the East China Sea.

    Science.gov (United States)

    Su, Kaijun; Du, Jinzhou; Baskaran, Mark; Zhang, Jing

    2017-08-01

    Lead-210 and 210Po have been widely used as tracers for quantifying particulate scavenging in the upper layer of the oceanic water column. In this study, we investigated the 210Po/210Pb disequilibrium in the water column of the PN section in the East China Sea (ECS) during autumn 2013. In most of the water column, a deficiency of 210Po was observed with respect to its parent nuclide 210Pb (i.e., a 210Po/210Pb activity ratio < 1.0). The (210Po/210Pb)dissolved, (210Po/210Pb)particulate and (210Po/210Pb)total activity ratios ranged from 0.29 to 0.71 (average: 0.53 ± 0.13, n = 27), 0.31 to 1.42 (average: 0.70 ± 0.27, n = 27) and 0.22 to 0.62 (average: 0.50 ± 0.12, n = 27), respectively. The distribution coefficients (Kd) of 210Po and 210Pb were 12.1× 104 ml g-1 and 8.8× 104 ml g-1, with an average (210Po/210Pb) total activity ratio of (0.50 ± 0.12, n = 27). However, over the continental shelf, planktonic detritus and fecal pellets appear to be the main carriers for 210Po, which preferentially scavenges 210Po and produces a lower (210Po/210Pb) total activity ratio (0.49 ± 0.12, n = 22) with a Kd for 210Po of 13.8× 104 ml g-1 in the water column. The variations in the fractionation factor (1.48 ± 0.66) of 210Po/210Pb reveal distinct differences between the distribution and scavenging of 210Po and 210Pb by particulate matter in different marine environments: in the estuarine zone (a high turbidity area), terrigenous suspended particulate matter scavenges 210Pb from the water column, while in areas dominated by biogenic particular matter, 210Po is preferentially scavenged from the water column. Using the 210Po/210Pb disequilibrium in the water column, we estimated the removal fluxes of POC from the upper waters downward to be 25.0 mg C m-2 d-1, comparable to those in other marginal seas. Moreover, a decreasing trend of POC removal fluxes was observed with increasing distance offshore. Copyright © 2016 Elsevier Ltd. All rights

  2. P-n junction diodes with polarization induced p-type graded In x Ga1-x N layer

    Science.gov (United States)

    Enatsu, Yuuki; Gupta, Chirag; Keller, Stacia; Nakamura, Shuji; Mishra, Umesh K.

    2017-10-01

    In this study, p-n junction diodes with polarization induced p-type layer are demonstrated on Ga polar (0001) bulk GaN substrates. A quasi-p-type region is obtained by linearly grading the indium composition in un-doped In x Ga1-x N layers from 0% to 5%, taking advantage of the piezoelectric and spontaneous polarization fields which exist in group III-nitride heterostructures grown in the typical (0001) or c-direction. The un-doped graded In x Ga1-x N layers needed to be capped with a thin Mg-doped In x Ga1-x N layer to make good ohmic contacts and to reduce the on-resistance of the p-n diodes. The Pol-p-n junction diodes exhibited similar characteristics compared to reference samples with traditional p-GaN:Mg layers. A rise in breakdown voltage from 30 to 110 V was observed when the thickness of the graded InGaN layer was increased from 100 to 600 nm at the same grade composition.

  3. Process for direct integration of a thin-film silicon p-n junction diode with a magnetic tunnel junction

    Science.gov (United States)

    Toet, Daniel; Sigmon, Thomas W.

    2003-01-01

    A process for direct integration of a thin-film silicon p-n junction diode with a magnetic tunnel junction for use in advanced magnetic random access memory (MRAM) cells for high performance, non-volatile memory arrays. The process is based on pulsed laser processing for the fabrication of vertical polycrystalline silicon electronic device structures, in particular p-n junction diodes, on films of metals deposited onto low temperature-substrates such as ceramics, dielectrics, glass, or polymers. The process preserves underlayers and structures onto which the devices are typically deposited, such as silicon integrated circuits. The process involves the low temperature deposition of at least one layer of silicon, either in an amorphous or a polycrystalline phase on a metal layer. Dopants may be introduced in the silicon film during or after deposition. The film is then irradiated with short pulse laser energy that is efficiently absorbed in the silicon, which results in the crystallization of the film and simultaneously in the activation of the dopants via ultrafast melting and solidification. The silicon film can be patterned either before or after crystallization.

  4. A simplified boron diffusion for preparing the silicon single crystal p-n junction as an educational device

    Science.gov (United States)

    Shiota, Koki; Kai, Kazuho; Nagaoka, Shiro; Tsuji, Takuto; Wakahara, Akihiro; Rusop, Mohamad

    2016-07-01

    The educational method which is including designing, making, and evaluating actual semiconductor devices with learning the theory is one of the best way to obtain the fundamental understanding of the device physics and to cultivate the ability to make unique ideas using the knowledge in the semiconductor device. In this paper, the simplified Boron thermal diffusion process using Sol-Gel material under normal air environment was proposed based on simple hypothesis and the feasibility of the reproducibility and reliability were investigated to simplify the diffusion process for making the educational devices, such as p-n junction, bipolar and pMOS devices. As the result, this method was successfully achieved making p+ region on the surface of the n-type silicon substrates with good reproducibility. And good rectification property of the p-n junctions was obtained successfully. This result indicates that there is a possibility to apply on the process making pMOS or bipolar transistors. It suggests that there is a variety of the possibility of the applications in the educational field to foster an imagination of new devices.

  5. Enhancement of the Si p-n diode NIR photoresponse by embedding β-FeSi2 nanocrystallites.

    Science.gov (United States)

    Shevlyagin, A V; Goroshko, D L; Chusovitin, E A; Galkin, K N; Galkin, N G; Gutakovskii, A K

    2015-10-05

    By using solid phase epitaxy of thin Fe films and molecular beam epitaxy of Si, a p(+)-Si/p-Si/β-FeSi2 nanocrystallites/n-Si(111) diode structure was fabricated. Transmission electron microscopy data confirmed a well-defined multilayered structure with embedded nanocrystallites of two typical sizes: 3-4 and 15-20 nm, and almost coherent epitaxy of the nanocrystallites with the Si matrix. The diode at zero bias conditions exhibited a current responsivity of 1.7 mA/W, an external quantum efficiency of about 0.2%, and a specific detectivity of 1.2 × 10(9) cm × Hz(1/2)/W at a wavelength of 1300 nm at room temperature. In the avalanche mode, the responsivity reached up to 20 mA/W (2% in terms of efficiency) with a value of avalanche gain equal to 5. The data obtained indicate that embedding of β-FeSi2 nanocrystallites into the depletion region of the Si p-n junction results in expansion of the spectral sensitivity up to 1600 nm and an increase of the photoresponse by more than two orders of magnitude in comparison with a conventional Si p-n junction. Thereby, fabricated structure combines advantage of the silicon photodiode functionality and simplicity with near infrared light detection capability of β-FeSi2.

  6. A simplified boron diffusion for preparing the silicon single crystal p-n junction as an educational device

    Energy Technology Data Exchange (ETDEWEB)

    Shiota, Koki, E-mail: a14510@sr.kagawa-nct.ac.jp; Kai, Kazuho; Nagaoka, Shiro, E-mail: nagaoka@es.kagawa-nct.ac.jp [National Institute of Technology, Kagawa College, Kagawa, Mitoyo, Takuma, Koda 551 (Japan); Tsuji, Takuto [National Institute of Technology, Suzuka College, Mie, Suzuka, Shiroko (Japan); Wakahara, Akihiro [Toyohashi University of Technology, Aichi, Toyohashi, Tenpaku, Hibarigaoka 1-1 (Japan); Rusop, Mohamad [University Technology Mara, Selangor, Shah Alam, 40450 (Malaysia)

    2016-07-06

    The educational method which is including designing, making, and evaluating actual semiconductor devices with learning the theory is one of the best way to obtain the fundamental understanding of the device physics and to cultivate the ability to make unique ideas using the knowledge in the semiconductor device. In this paper, the simplified Boron thermal diffusion process using Sol-Gel material under normal air environment was proposed based on simple hypothesis and the feasibility of the reproducibility and reliability were investigated to simplify the diffusion process for making the educational devices, such as p-n junction, bipolar and pMOS devices. As the result, this method was successfully achieved making p+ region on the surface of the n-type silicon substrates with good reproducibility. And good rectification property of the p-n junctions was obtained successfully. This result indicates that there is a possibility to apply on the process making pMOS or bipolar transistors. It suggests that there is a variety of the possibility of the applications in the educational field to foster an imagination of new devices.

  7. Enhancement of the Si p-n diode NIR photoresponse by embedding β-FeSi2 nanocrystallites

    Science.gov (United States)

    Shevlyagin, A. V.; Goroshko, D. L.; Chusovitin, E. A.; Galkin, K. N.; Galkin, N. G.; Gutakovskii, A. K.

    2015-01-01

    By using solid phase epitaxy of thin Fe films and molecular beam epitaxy of Si, a p+-Si/p-Si/β-FeSi2 nanocrystallites/n-Si(111) diode structure was fabricated. Transmission electron microscopy data confirmed a well-defined multilayered structure with embedded nanocrystallites of two typical sizes: 3–4 and 15–20 nm, and almost coherent epitaxy of the nanocrystallites with the Si matrix. The diode at zero bias conditions exhibited a current responsivity of 1.7 mA/W, an external quantum efficiency of about 0.2%, and a specific detectivity of 1.2 × 109 cm × Hz1/2/W at a wavelength of 1300 nm at room temperature. In the avalanche mode, the responsivity reached up to 20 mA/W (2% in terms of efficiency) with a value of avalanche gain equal to 5. The data obtained indicate that embedding of β-FeSi2 nanocrystallites into the depletion region of the Si p-n junction results in expansion of the spectral sensitivity up to 1600 nm and an increase of the photoresponse by more than two orders of magnitude in comparison with a conventional Si p-n junction. Thereby, fabricated structure combines advantage of the silicon photodiode functionality and simplicity with near infrared light detection capability of β-FeSi2. PMID:26434582

  8. Forward $\\pi^{+-}$ production in p-$O_2$ and p-$N_2$ interactions at 12 GeV/c

    CERN Document Server

    Catanesi, M.G.; Edgecock, R.; Ellis, M.; Gossling, C.; Bunyatov, S.; Krasnoperov, A.; Popov, B.; Tereschenko, V.; Di Capua, E.; Vidal-Sitjes, G.; Artamonov, A.; Giani, S.; Gilardoni, S.; Gorbunov, P.; Grant, A.; Grossheim, A.; Ivanchenko, A.; Ivanchenko, V.; Kayis-Topaksu, A.; Panman, J.; Papadopoulos, I.; Tcherniaev, E.; Tsukerman, I.; Wiebusch, C.; Zucchelli, P.; Blondel, A.; Borghi, S.; Morone, M.C.; Prior, G.; Schroeter, R.; Meurer, C.; Gastaldi, U.; Mills, G.B.; Graulich, J.S.; Gregoire, G.; Bonesini, M.; Ferri, F.; Kirsanov, M.; Bagulya, A.; Grichine, V.; Polukhina, N.; Palladino, V.; Coney, L.; Schmitz, D.; Barr, G.; Bobisut, F.; Gibin, D.; Guglielmi, A.; Mezzetto, M.; Dumarchez, J.; Dore, U.; Orestano, D.; Pastore, F.; Tonazzo, A.; Tortora, L.; Booth, C.; Howlett, L.; Bogomilov, M.; Kolev, D.; Tsenov, R.; Piperov, Stefan; Temnikov, P.; Apollonio, M.; Chimenti, P.; Giannini, G.; Burguet-Castell, J.; Cervera-Villanueva, A.; Gomez-Cadenas, J.J.; Martin-Albo, J.; Sorel, M.

    2008-01-01

    Measurements of double-differential charged pion production cross-sections in interactions of 12 GeV/c protons on O_2 and N_2 thin targets are presented in the kinematic range 0.5 GeV/c < p_{\\pi} < 8 GeV/c and 50 mrad < \\theta_{\\pi} < 250 mrad (in the laboratory frame) and are compared with p--C results. For p--N_2 (p--O_2) interactions the analysis is performed using 38576 (7522) reconstructed secondary pions. The analysis uses the beam instrumentation and the forward spectrometer of the HARP experiment at CERN PS. The measured cross-sections have a direct impact on the precise calculation of atmospheric neutrino fluxes and on the improved reliability of extensive air shower simulations by reducing the uncertainties of hadronic interaction models in the low energy range. In particular, the present results allow the common hypothesis that p--C data can be used to predict the p--N_2 and p--O_2 pion production cross-sections to be tested.

  9. Axial pn-junctions formed by MOVPE using DEZn and TESn in vapor-liquid-solid grown GaAs nanowires

    Science.gov (United States)

    Regolin, I.; Gutsche, C.; Lysov, A.; Blekker, K.; Li, Zi-An; Spasova, M.; Prost, W.; Tegude, F.-J.

    2011-01-01

    We report on axial pn-junctions in GaAs nanowires. The nanowires were grown by MOVPE on (1 1 1)B GaAs substrates using the vapor-liquid-solid mechanism in combination with Au seed particles. At the low growth temperature of 400 °C any additional growth on the nanowire sidewalls can be excluded such that a pure axial pn-junction is realized. p-Type doping was provided by diethyl zinc, while tetraethyl tin was introduced for n-type doping. The impact of dopant supply was investigated both on structural properties and on carrier density. The carrier type was independently verified by processed nanowire metal-insulator FETs. The lengths of the whole pn-GaAs nanowires reach up to 20 μm while their diameters are up to a few 100 nm, as defined by the Au seed particles used. The pn-GaAs nanowire device exhibits diode-like I- V characteristics and strong electroluminescence. While the reverse current is in the low pA-regime, the forward current reaches a few μA, limited by the n-doped side. A diffusion voltage VD=1.4 V is determined, which corresponds to the GaAs band gap energy. To our knowledge this is the first axial GaAs pn-diode realized in a single GaAs nanowire.

  10. Configuration-dependent anti-ambipolar van der Waals p-n heterostructures based on pentacene single crystal and MoS2.

    Science.gov (United States)

    Dong, Ji; Liu, Fengjing; Wang, Feng; Wang, Jiawei; Li, Molin; Wen, Yao; Wang, Liang; Wang, Gongtang; He, Jun; Jiang, Chao

    2017-06-08

    Recently, van der Waals heterostructures (vdWHs) have trigged intensive interest due to their novel electronic and optoelectronic properties. The vdWHs could be achieved by stacking two dimensional layered materials (2DLMs) on top of another and vertically kept by van der Waals forces. Furthermore, organic semiconductors are also known to interact via van der Waals forces, which offer an alternative for the fabrication of organic-inorganic p-n vdWHs. However, the performances of organic-inorganic p-n vdWHs produced so far are rather poor, owing to the unmatched electrical property between the 2DLMs and organic polycrystalline films. To make improvements in such novel heterostructure architectures, here we adopt high quality organic single crystals instead of polycrystalline films to construct a pentacene/MoS 2 p-n vdWH. The vdWHs show a much higher current density and better anti-ambipolar characteristics with a highest transconductance of 211 nS. Moreover, device configuration-dependent transfer characteristics are demonstrated and a mechanism of a gate bias modulated vertical space charge zone existing at the vertical p-n vdWHs interface is proposed. These findings provide a new route to optimize the organic-inorganic p-n vdWHs and a guideline for studying the intrinsic properties of vdWHs.

  11. Nano-engineering of p-n CuFeO2-ZnO heterojunction photoanode with improved light absorption and charge collection for photoelectrochemical water oxidation

    Science.gov (United States)

    Karmakar, Keshab; Sarkar, Ayan; Mandal, Kalyan; Gopal Khan, Gobinda

    2017-08-01

    The effective utilization of abundant visible solar light for photoelectrochemical water splitting is a green approach for energy harvesting, to reduce the enormous rise of carbon content in the atmosphere. Here, a novel efficient design strategy for p-n type nano-heterojunction photoanodes is demonstrated, with the goal of improving water splitting efficiency by growing low band gap p-CuFeO2 nanolayers on n-ZnO nanorods by an easy and scalable electrochemical route. The photoconversion efficiency of p-n CuFeO2/ZnO photoanodes is found to be ˜450% higher than that of pristine ZnO nanorod electrodes under visible solar light illumination (λ > 420 nm, intensity 10 mW cm-2). The p-n CuFeO2/ZnO nano-engineering not only boosts the visible light absorption but also resolves limitations regarding effective charge carrier separation and transportation due to interfacial band alignment. This photoanode also shows remarkably enhanced stability, where the formation of p-n nano-heterojunction enhances the easy migration of holes to the electrode/electrolyte interface, and of electrons to the counter electrode (Pt) for hydrogen generation. Therefore, this work demonstrates that p-n nano-engineering is a potential strategy to design light-harvesting electrodes for water splitting and clean energy generation.

  12. Changes in screen-printed ZnO/CuInSe2 p-n junction before and after laser ablation

    Science.gov (United States)

    Ogurcovs, A.; Gerbreders, Vj; Tamanis, E.; Gerbreders, A.

    2015-06-01

    In the experiments, ZnO and CuInSe2 semiconductor powders were used (the latter produced by the high-temperature synthesis method). Microstructural properties of the powders were analyzed using X-Ray diffraction and SEM. The experimental ZnO/CuInSe2 samples were prepared by the screen printing technique. The V-I measurements of the samples indicated the presence of a p-n junction in the ZnO/CuInSe2 contact zone. The samples were exposed to artificial solar radiation, during which an exponential decay of photo-emf was observed. It was shown that the starting conductive properties of the p-n junction restores in ˜ 15 min after the exposition. Laser ablation technique was applied to ZnO/CuInSe2 p-n junction with purpose to improve its performance and quality. After several attempts, significant changes in electrical properties of samples was observed. Improvenent of p-n junction can be achieved only at single attempt at certain amount of delivered energy. Futherablation attempt leads to degradation of p-n junction of samples.

  13. Controlling Axial p-n Heterojunction Abruptness Through Catalyst Alloying in Vapor-Liquid-Solid Grown Semiconductor Nanowires

    Energy Technology Data Exchange (ETDEWEB)

    Perea, Daniel E.; Schreiber, Daniel K.; Devaraj, Arun; Thevuthasan, Suntharampillai; Yoo, Jinkyoung; Dayeh, Shadi A.; Picraux, Samuel T.

    2012-07-30

    The p-n junction can be regarded as the most important electronic structure that is responsible for the ubiquity of semiconductor microelectronics today. Efforts to continually scale down the size of electronic components is guiding research to explore the use of nanomaterials synthesized from a bottom-up approach - group-IV semiconductor nanowires being one such material. However, Au-catalyzed synthesis of Si/Si1-x-Gex semiconductor nanowire heterojunctions using the commonly-used vapor-liquid-solid (VLS) growth technique results in diffuse heterojunction interfaces [1], leading to doubts of producing compositionally-sharp p-n junctions using this approach. However, we have recently reported the ability to increase Ge-Si nanowire heterojunction abruptness by VLS synthesis from a Au(1-x)Ga(x) catalyst alloy as shown by EDX analysis in an SEM [2]. In this work, we have extended the use of a AuGa catalyst alloy to produce more compositionally abrupt p-n junction interfaces compared to using pure Au as directly measured by atom probe tomography. As shown in Figure 1(a-b), individual Ge-Si heterostructured nanowires were grown vertically atop Ge(111) microposts. Direct growth on the microposts provides a facile approach to nanowire analysis which circumvents the need to use FIB-based sample preparation techniques. Both nanowires grown from pure Au and a AuGa catalyst alloy were analyzed. The corresponding 3D APT reconstruction of an individual heterostructured nanowire is shown in Figure 1(c) with the corresponding materials labeled. A 1-dimensional composition profile along the analysis direction in Figure 1(d) confirms an increase in heterojunction abruptness for nanowires grown from AuGa (~10nm) compared to nanowires grown from pure Au (~65nm). Analysis of the P distribution within the Si region (Figure 1(e)) indicates that P reaches a constant distribution over approximately 10nm when incorporated through the AuGa catalyst, whereas it continually increases over 100

  14. Synthesis and characterization of metal oxide semiconductors by a facile co-electroplating-annealing method and formation of ZnO/CuO pn heterojunctions with rectifying behavior

    Science.gov (United States)

    Turkdogan, Sunay; Kilic, Bayram

    2018-01-01

    We have developed a unique growth method and demonstrated the growth of CuO and ZnO semiconductor materials and the fabrication of their pn heterojunctions in ambient atmosphere. The pn heterojunctions were constructed using inherently p-type CuO and inherently n-type ZnO materials. Both p- and n-type semiconductors and pn heterojunctions were prepared using a simple but versatile growth method that relies on the transformation of electroplated Cu and Zn metals into CuO and ZnO semiconductors, respectively and is capable of a large-scale production desired in most of the applications. The structural, chemical, optical and electrical properties of the materials and junctions were investigated using various characterization methods and the results show that our growth method, materials and devices are quite promising to be utilized for various applications including but not limited to solar cells, gas/humidity sensors and photodetectors.

  15. The p-n junction formation in Hg{sub 1-x}Cd {sub x}Te by laser annealing method

    Energy Technology Data Exchange (ETDEWEB)

    Dumanski, L. [Institute of Physics, University of Rzeszow, Rejtana 16A, 35-959 Rzeszow (Poland)]. E-mail: lukasz@omeganet.internetdsl.pl; Bester, M. [Institute of Physics, University of Rzeszow, Rejtana 16A, 35-959 Rzeszow (Poland); Virt, I.S. [Section of Experimental Physics, Pedagogical University, Franco 24, 82-100 Drogobych (Ukraine); Institute of Biotechnology, University of Rzeszow, Rejtana 16A, 35-959 Rzeszow (Poland); Kuzma, M. [Institute of Physics, University of Rzeszow, Rejtana 16A, 35-959 Rzeszow (Poland)

    2006-04-30

    The formation of p-n junctions in Hg{sub 1-x}Cd {sub x}Te is still an open research task. In this paper, laser treatment of n-type Hg{sub 1-x}Cd {sub x}Te samples resulting in the formation of a p-n junction is studied. The YAG:Nd{sup 3+} laser with pulse duration of 250 {mu}s or 40 ns was used. The energy density of laser beam was below the threshold of sample surface melting. The interpretation of the results is based on a model of defects formation related to interstitial mercury diffusion following laser irradiation. The Hall measurements clearly point out to a simple p-n junction. The resistance of samples shows the long time relaxation described by the 1/2 power law, which is attributable to the defect diffusion processes, but not to the changes in the electron-hole systems.

  16. Design principles for photovoltaic devices based on Si nanowires with axial or radial p-n junctions.

    Science.gov (United States)

    Christesen, Joseph D; Zhang, Xing; Pinion, Christopher W; Celano, Thomas A; Flynn, Cory J; Cahoon, James F

    2012-11-14

    Semiconductor nanowires (NWs) are a developing platform for electronic and photonic technologies, and many demonstrated devices utilize a p-type/n-type (p-n) junction encoded along either the axial or radial directions of the wires. These miniaturized junctions enable a diverse range of functions, from sensors to solar cells, yet the physics of the devices has not been thoroughly evaluated. Here, we present finite-element modeling of axial and radial Si NW p-n junctions with total diameters of ~240 nm and donor/acceptor doping levels ranging from 10(16) to 10(20) cm(-3). We evaluate the photovoltaic performance of horizontally oriented NWs under 1 sun illumination and compare simulated current-voltage data to experimental measurements, permitting detailed analysis of NW performance, limitations, and prospect as a technology for solar energy conversion. Although high surface-to-volume ratios are cited as detrimental to NW performance, radial p-n junctions are surprisingly insensitive to surface recombination, with devices supporting open-circuit voltages (V(OC)) of ~0.54 V and internal quantum efficiencies of 95% even with high surface recombination velocities (SRVs) of 10(5) cm/s. Axial devices, in which the depletion region is exposed to the surface, are far more sensitive to SRV, requiring substantially lower values of 10(3)-10(4) cm/s to produce the same level of performance. For low values of the SRV (0.70 V if the bulk minority carrier lifetime is 1 μs or greater. Experimental measurements on NWs grown by a vapor-liquid-solid mechanism yield V(OC) of 0.23 and 0.44 V for axial and radial NWs, respectively, and show that axial devices are limited by a SRV of ~7 × 10(3) cm/s while radial devices are limited by a bulk lifetime of ~3 ns. The simulations show that with further development the electrical characteristics of 200-300 nm Si NWs are sufficient to support power-conversion efficiencies of 15-25%. The analysis presented here can be generalized to other

  17. C-H and H-H Bond Activation via Ligand Dearomatization/Rearomatization of a PN3P-Rhodium(I) Complex

    KAUST Repository

    Huang, Kuo-Wei

    2015-04-13

    A neutral complex PN3P-Rh(I)Cl (2) was prepared from a reaction of the PN3P pincer ligand (1) with [Rh(COD)Cl]2 (COD = 1,5-cyclooctadiene). Upon treatment with a suitable base, H–H and Csp2–H activation reactions can be achieved through the deprotonation/reprotonation of one of the N–H arms and dearomatization/rearomatization of the central pyridine ring with the oxidation state of Rh remaining I.

  18. An optimum PN code search technique for a given apriori signal location density. [PseudoNoise in radar detection

    Science.gov (United States)

    Holmes, J. K.; Woo, K. T.

    1978-01-01

    A method is presented for optimizing (minimizing) the acquisition time for a PN-type spread spectrum system when the a priori probability density function is not uniform. For an assumed a priori Gaussian density function, calculations show that the acquisition time, when the 0.5 probability acquisition time is used as a measure of acquisition time, is reduced by 40% for a cell detection probability of 0.25 and when three sweeps are used. For the same parameters and with four sweeps the acquisition time is reduced by 41%. When the acquisition time probability is set to 0.9 instead of 0.5, the reduction is 25% of the uniform sweep time.

  19. GaN nanowire/thin film vertical structure p-n junction light-emitting diodes

    Science.gov (United States)

    Hong, Young Joon; Lee, Chul-Ho; Beom Park, Jun; Jin An, Sung; Yi, Gyu-Chul

    2013-12-01

    Here, we report vertical-type GaN nanowire-based light-emitting diodes (LEDs) fabricated by the metal-catalyzed vapor-liquid-solid (VLS) method. The nickel-catalyzed VLS process yielded both n-GaN nanowires and GaN nanoislands on substrates. The nanoislands markedly deteriorated the diode and electroluminescent characteristics in n-nanowire/p-film LED structures because of parasitic resistance and deep level emission caused by nanoislands. By burying the nanoislands with an insulating layer and adopting coaxial p-n junction nanowire structures, nanowire-based LEDs were shown to exhibit superior device performance, including highly rectifying and monochromatic electroluminescent characteristics. Thus, the undesirable effects associated with nanoislands were considerably suppressed. This work provides a rationale for designing high-performance vertical nanowire-based LEDs.

  20. Current rectification in a single GaN nanowire with a well-defined p-n junction

    Science.gov (United States)

    Cheng, Guosheng; Kolmakov, Andrei; Zhang, Youxiang; Moskovits, Martin; Munden, Ryan; Reed, Mark A.; Wang, Guangming; Moses, Daniel; Zhang, Jinping

    2003-08-01

    This letter discusses Mg incorporation in GaN nanowires with diameters ˜35 nm, fabricated by vapor-liquid-solid synthesis in p-type nanowires. Turning on the Mg doping halfway through the synthesis produced nanowires with p-n junctions that showed excellent rectification properties down to 2.6 K. The nanowires are shown to possess good-quality, crystalline, hexagonal GaN inner cores surrounded by an amorphous GaN outer layer. Most wires grow such that the crystalline c axis is normal to the long axis of the nanowire. The temperature dependence of the current-voltage characteristics is consistent with electron tunneling through a voltage-dependent barrier.

  1. Physically processed Ag-doped ZnO nanowires for all-ZnO p-n diodes.

    Science.gov (United States)

    Song, Yong-Won; Kim, Kyoungwon; Ahn, Jae Pyoung; Jang, Gun-Eik; Lee, Sang Yeol

    2009-07-08

    We synthesize and analyze Ag-doped ZnO (SZO) nanowires (NWs) via a vapor-liquid-solid mechanism in a physical vapor deposition. The process condition for the SZO NW formation is optimized by adjusting the kinetic energy and the flux of the laser-ablated particles by hot-wall control. Electron microscopes ensure excellent morphologies of the doped NWs obtained. We confirm p-type doping effects, with low temperature photoluminescence used to trace the A(0)X peak. We realize diodes with all-ZnO-based p-n junctions of SZO NWs and Ga-doped ZnO thin films, resulting in asymmetric I-V characteristics with the turn on voltage of 3.8 V.

  2. On the formation of molecules and solid-state compounds from the AGB to the PN phases

    Science.gov (United States)

    García-Hernández, D. A.; Manchado, A.

    2016-07-01

    During the asymptoyic giant branch (AGB) phase, different elements are dredge- up to the stellar surface depending on progenitor mass and metallicity. When the mass loss increases at the end of the AGB, a circumstellar dust shell is formed, where different (C-rich or O-rich) molecules and solid-state compounds are formed. These are further processed in the transition phase between AGB stars and planetary nebulae (PNe) to create more complex organic molecules and inorganic solid-state compounds (e.g., polycyclic aromatic hydrocarbons, fullerenes, and graphene precursors in C-rich environments and oxides and crystalline silicates in O-rich ones). We present an observational review of the different molecules and solid-state materials that are formed from the AGB to the PN phases. We focus on the formation routes of complex fullerene (and fullerene-based) molecules as well as on the level of dust processing depending on metallicity.

  3. ANALISIS PUTUSAN HAKIM NOMOR: 113/Pid.B/2007/PN.Pml TENTANG TINDAK PIDANA PENYALAHGUNAAN NARKOTIKA

    Directory of Open Access Journals (Sweden)

    Saryono Hanadi

    2010-01-01

    Full Text Available Decree Number: 113/Pid.B/2007/PN.Pml relating with the case of abuse of narcotic that conducted by Bambang Suroto alias Gentolet bin Rifa’i. In this case, public Prosecutor assert with laminated assertion which are Primer Assertion by article 81 sentence (1 letter a Law No.22 Year 1997 and subsidiary assertion by article 85 letter a Law No.22 Year 1997 concerning Narcotic. In this case, the decree cannot be told as a progressive decree because it not considering article 47 Law No. 12 Year 1997 concerning Narcotic. Judge ought to be considering the way to solve the problem by commanding the defendant to have the rehabilitation as a prevention without punishment to influencing views of society on crime.

  4. Analisis Putusan No. 55/PID.B/2015/PN-BNA tentang Tindak Pidana Pencurian dengan Pemberatan

    Directory of Open Access Journals (Sweden)

    Nurhafifah Nurhafifah

    2016-08-01

    ABSTRACT. Based on the provisions of Article 143 paragraph (2 b KUHAP, declare that the material terms of the indictment must describe accurately, clear and complete for the offenses charged by the state the time and place the criminal act was carried out. In the indictment the Prosecution of decision No.55/PID.B/2015/PN-BNA, clear elements referred to in the article has not fulfilled. Likewise in the legal considerations of the judge's decision, which does not contain clear about the facts revealed at the hearing juridical. The charges filed by the Public Prosecutor has not elaborate on the description carefully and clearly in accordance with Article 143 paragraph (2 b KUHAP. Similarly, in the legal considerations of the judge's decision, which does not pay attention juridical facts revealed in court. Not fulfilled the provisions of Article 143 paragraph (92 letter b KUHAP resulted in the indictment null and void.

  5. ANALISIS PUTUSAN HAKIM NOMOR: 113/Pid.B/2007/PN.Pml TENTANG TINDAK PIDANA PENYALAHGUNAAN NARKOTIKA

    Directory of Open Access Journals (Sweden)

    Saryono Hanadi

    2010-01-01

    Full Text Available Decree Number: 113/Pid.B/2007/PN.Pml relating with the case of abuse of narcotic that conducted by Bambang Suroto alias Gentolet bin Rifa’i. In this case, public Prosecutor assert with laminated assertion which are Primer Assertion by article 81 sentence (1 letter a Law No.22 Year 1997 and subsidiary assertion by article 85 letter a Law No.22 Year 1997 concerning Narcotic. In this case, the decree cannot be told as a progressive decree because it not considering article 47 Law No. 12 Year 1997 concerning Narcotic. Judge ought to be considering the way to solve the problem by commanding the defendant to have the rehabilitation as a prevention without punishment to influencing views of society on crime. Keyword: abuse of narcotic, progressive decree and rehabilitation

  6. Efficiently Harvesting Sun Light for Silicon Solar Cells through Advanced Optical Couplers and A Radial p-n Junction Structure

    Directory of Open Access Journals (Sweden)

    Hsin-Cheng Lee

    2010-04-01

    Full Text Available Silicon-based solar cells (SCs promise to be an alternative energy source mainly due to: (1 a high efficiency-to-cost ratio, (2 the absence of environmental-degradation issues, and (3 great reliability. Transition from wafer-based to thin-film SC significantly reduces the cost of SCs, including the cost from the material itself and the fabrication process. However, as the thickness of the absorption (or the active layer decreases, the energy-conversion efficiency drops dramatically. As a consequence, we discuss here three techniques to increase the efficiency of silicon-based SCs: (1 photonic crystal (PC optical couplers and (2 plasmonic optical couplers to increase efficiency of light absorption in the SCs, and (3 a radial p-n junction structure, decomposing light absorption and diffusion path into two orthogonal directions. The detailed mechanisms and recent research progress regarding these techniques are discussed in this review article.

  7. Single-crystal N-polar GaN p-n diodes by plasma-assisted molecular beam epitaxy

    Science.gov (United States)

    Cho, YongJin; Hu, Zongyang; Nomoto, Kazuki; Xing, Huili Grace; Jena, Debdeep

    2017-06-01

    N-polar GaN p-n diodes are realized on single-crystal N-polar GaN bulk wafers by plasma-assisted molecular beam epitaxy growth. The current-voltage characteristics show high-quality rectification and electroluminescence characteristics with a high on currents ˜10 kA/cm2, low off currents 109, and interband photon emission. The measured electroluminescence spectrum is dominated by a strong near-band edge emission, while deep level luminescence is greatly suppressed. A very low dislocation density leads to a high reverse breakdown electric field of ˜2.2 MV/cm without fields plates—the highest reported for N-polar epitaxial structures. The low leakage current N-polar diodes open up several potential applications in polarization-engineered photonic and electronic devices.

  8. Inorganic-organic p-n heterojunction nanotree arrays for a high-sensitivity diode humidity sensor.

    Science.gov (United States)

    Wang, Ke; Qian, Xuemin; Zhang, Liang; Li, Yongjun; Liu, Huibiao

    2013-06-26

    Large-area and ordered arrays (16 cm(2)) of an inorganic-organic p-n heterojunction nanotree (NT) were successfully fabricated. The nanotree arrays consist of ZnO nanorods (NRs) as backbones and CuTCNQ (TCNQ = 7,7,8,8-tetracyanoquinodimethane) NRs as branches. The sizes of CuTCNQ NRs can be tuned by the thickness of the Cu layer deposited on the surface of ZnO NR. The CuTCNQ/ZnO NT arrays displayed excellent diode nature and obvious size-dependent rectification ratios were observed. Moreover, the CuTCNQ/ZnO NT arrays were first applied for the fabrication of a diode-type humidity sensor, which displayed ultrahigh sensitivity and quick response/recovery properties at room temperature. The detection limitation of this new diode-type humidity sensor lowers to 5% relative humidity (RH).

  9. Operando x-ray photoelectron emission microscopy for studying forward and reverse biased silicon p-n junctions

    Energy Technology Data Exchange (ETDEWEB)

    Barrett, N., E-mail: nick.barrett@cea.fr; Gottlob, D. M.; Mathieu, C.; Lubin, C. [SPEC, CEA, CNRS, Université Paris-Saclay, CEA Saclay, 91191 Gif-sur-Yvette Cedex (France); Passicousset, J. [SPEC, CEA, CNRS, Université Paris-Saclay, CEA Saclay, 91191 Gif-sur-Yvette Cedex (France); IFP Energies nouvelles, Rond-point de l’échangeur de Solaize, BP 3, 69360 Solaize (France); Renault, O.; Martinez, E. [University Grenoble-Alpes, 38000 Grenoble, France and CEA, LETI, MINATEC Campus, 38054 Grenoble (France)

    2016-05-15

    Significant progress in the understanding of surfaces and interfaces of materials for new technologies requires operando studies, i.e., measurement of chemical, electronic, and magnetic properties under external stimulus (such as mechanical strain, optical illumination, or electric fields) applied in situ in order to approach real operating conditions. Electron microscopy attracts much interest, thanks to its ability to determine semiconductor doping at various scales in devices. Spectroscopic photoelectron emission microscopy (PEEM) is particularly powerful since it combines high spatial and energy resolution, allowing a comprehensive analysis of local work function, chemistry, and electronic structure using secondary, core level, and valence band electrons, respectively. Here we present the first operando spectroscopic PEEM study of a planar Si p-n junction under forward and reverse bias. The method can be used to characterize a vast range of materials at near device scales such as resistive oxides, conducting bridge memories and domain wall arrays in ferroelectrics photovoltaic devices.

  10. Fabrication of a Graphene/ZnO based p-n junction device and its ultraviolet photoresponse properties

    Science.gov (United States)

    Kwon, Young-Tae; Kang, Sung-Oong; Cheon, Ji-Ae; Song, Yoseb; Lee, Jong-Jin; Choa, Yong-Ho

    2017-09-01

    Graphene with a zero-bandgap energy is easily doped using a chemical dopant, and a shift upwards or downwards in the Fermi level is generated. Moreover, the integration of inorganic material into the doped graphene changes the physical and chemical properties of the material. For this purpose, we successfully fabricated a p-n junction device by depositing an n-typed ZnO layer on p-doped graphene and studied the ultraviolet (UV) photoresponse properties under a photocurrent (UV light on) and a dark current (UV light off). Two devices, lateral and vertical, were developed by alternating the thickness of the ZnO layer, and the photoresponse mechanisms were described on the basis of the contact potential difference.

  11. Two dimensional MoS{sub 2}/graphene p-n heterojunction diode: Fabrication and electronic characteristics

    Energy Technology Data Exchange (ETDEWEB)

    Su, Wei-Jhih [Graduate Institute of Electro-Optical Engineering, National Taiwan University of Science and Technology, 43, Section 4, Keelung Road, Taipei 10607, Taiwan (China); Chang, Hsuan-Chen [Department of Electronic and Computer Engineering, National Taiwan University of Science and Technology, 43, Section 4, Keelung Road, Taipei 10607, Taiwan (China); Shih, Yi-Ting [Graduate Institute of Electro-Optical Engineering, National Taiwan University of Science and Technology, 43, Section 4, Keelung Road, Taipei 10607, Taiwan (China); Wang, Yi-Ping [Department of Electronic and Computer Engineering, National Taiwan University of Science and Technology, 43, Section 4, Keelung Road, Taipei 10607, Taiwan (China); Hsu, Hung-Pin [Department of Electronic Engineering, Ming Chi University of Technology, 84 Gungjuan Road, New Taipei City 24301, Taiwan (China); Huang, Ying-Sheng [Graduate Institute of Electro-Optical Engineering, National Taiwan University of Science and Technology, 43, Section 4, Keelung Road, Taipei 10607, Taiwan (China); Department of Electronic and Computer Engineering, National Taiwan University of Science and Technology, 43, Section 4, Keelung Road, Taipei 10607, Taiwan (China); Lee, Kuei-Yi, E-mail: kylee@mail.ntust.edu.tw [Graduate Institute of Electro-Optical Engineering, National Taiwan University of Science and Technology, 43, Section 4, Keelung Road, Taipei 10607, Taiwan (China); Department of Electronic and Computer Engineering, National Taiwan University of Science and Technology, 43, Section 4, Keelung Road, Taipei 10607, Taiwan (China)

    2016-06-25

    Molybdenum disulfide (MoS{sub 2}) films are currently the most potential semiconductor materials of the two-dimensional nano-material heterojunction. Few-layer MoS{sub 2} is an n-type semiconductor that has good mechanical strength, high carrier mobility, and has similar thickness as graphene. Graphene is presently the thinnest two-dimensional material with good thermal conductivity and high carrier mobility. The graphene Fermi level can be precisely controlled using the oxygen adsorption. Therefore, graphene can be tuned from zero-gap to p-type semiconductor material using the amount of adsorbed oxygen. In this study we combine few-layer MoS{sub 2} and graphene to produce a heterojunction and exhaustively study the interface properties for heterojunction diode application. According to the results, the MoS{sub 2} band-gap increases with decreasing thickness. The I–V characteristics of the MoS{sub 2}/Graphene p-n junction diodes can be precisely tuned by adjusting different thicknesses of the MoS{sub 2} films. By applying our fabricating method, MoS{sub 2}/Graphene heterojunction diode can be easily constructed and have potential to different applications. - Highlights: • We controlled the layer thickness of MoS{sub 2} by different exfoliation times. • We presented Raman scattering of MoS{sub 2} and define their layers number. • The few-layer MoS{sub 2}/graphene pn junction diode was synthesized. • We measured the device current and voltage characteristics. • The built-in potential barrier could be adjusted by controlling MoS{sub 2} thicknesses.

  12. Ancora sui tempi di tragitto delle Pn provenienti dalla Sicilia Tabelle numeriche per varie profondità ipocentrali

    Directory of Open Access Journals (Sweden)

    G. PANNOCCHIA

    1974-06-01

    Full Text Available This paper follows the foregoing studies by the A.A. already carried out on the earthquakes occurred in Western Sicily. The hypocentral data investigation concerning a further large earthquake of the swarm, has confirmed an hypocentral depth close to the "Molio". Grouping conveniently the investigated earthquakes it was possible to calculate the longitudinal waves travel-times curves at the following depths: 30, 35, 40, 45, 50, 00 km (A < 20°. Some interesting results concerning the first impulses of P„ waves have been found (existence of two series of waves, P,n and IJ„2 having a slightly different velocity. Five curves for each examined h have been calculated; the P„ (the general using all the onsets including the ones whose residuals resulted later to be about three seconds: the Pni and the P„2 representing a Pn subdivision obtained by reducing the residuals range: the P„ -^13° and the P„ (10°M 20° for 2» < A < 13° and 10° < A < 20° respectively calculated. (The P„ 13° approaches to a straight line, in accordance with other estimations for curves investigated along shorter paths. The paper contains also all numerical tables related to 29 travel-times curves calculated every 20 km; as well as the curve corresponding to li = 17.5 km. The last curve has been obtained averaging the values of depth from 5 km to 30 km in order to fill the gap 0 i—i 30 km.

  13. Increased efficiency in pn-junction PbS QD solar cells via NaHS treatment of the p-type layer

    NARCIS (Netherlands)

    Speirs, Mark J.; Balazs, Daniel M.; Dirin, Dmitry N.; Kovalenko, Maksym V.; Loi, Maria Antonietta

    2017-01-01

    Lead sulfide quantum dot (PbS QD) solar cell efficiencies have improved rapidly over the past years due in large part to intelligent band alignment considerations. A pn-junction can be formed by connecting PbS layers with contrasting ligands. However, the resulting doping concentrations are

  14. Transparent CH{sub 3}NH{sub 3}SnCl{sub 3}/Al-ZnO p-n heterojunction diode

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Sunil, E-mail: skbgudha@gmail.com; Ansari, Mohd Zubair; Khare, Neeraj [Department of Physics, Indian Institute of Technology, Hauz Khas, New Delhi, Delhi-110016 (India)

    2016-05-23

    A p-type Organic inorganic tin chloride (CH{sub 3}NH{sub 3}SnCl{sub 3}) perovskite thin film has been synthesized by solution method. An n-type 1% Al doped ZnO (AZO) film has been deposited on FTO substrate by ultrasonic assisted chemical vapor deposition technique. A transparent CH{sub 3}NH{sub 3}SnCl{sub 3}/AZO p-n heterojunction diode has been fabricated by spin coating technique. CH{sub 3}NH{sub 3}SnCl{sub 3}/AZO p-n heterojunction shows 75% transparency in the visible region. I-V characteristic of CH{sub 3}NH{sub 3}SnCl{sub 3}/AZO p-n heterojunction shows rectifying behavior of the diode. The diode parameters calculated as ideality factor η=2.754 and barrier height Φ= 0.76 eV. The result demonstrates the potentiality of CH{sub 3}NH{sub 3}SnCl{sub 3}/AZO p-n heterojunction for transparent electronics.

  15. Synthesis of group 10 metal complexes with a new unsymmetrical PN3P-pincer ligand through ligand post-modification: Structure and reactivity

    KAUST Repository

    Wang, Xiufang

    2017-01-01

    A post-modification strategy are used to synthesize a new class of diimine-amido PN3P-pincer group-10 transition metal complexes. The coordination chemistry and the thermal stabilities of their organometallic derivatives are characterized and investigated.

  16. Evidence of Black Hole Spin in GX 339-4: XMM-Newton/EPIC-pn and RXTE Spectroscopy of the Very High State

    NARCIS (Netherlands)

    Miller, J.M.; Fabian, A.C.; Reynolds, C.S.; Nowak, M.A.; Homan, J.; Freyberg, M.J.; Ehle, M.; Belloni, T.; Wijnands, R.A.D.; van der Klis, M.; Charles, P.A.; Lewin, W.H.G.

    2004-01-01

    We have analyzed spectra of the Galactic black hole GX 339-4 obtained through simultaneous 76 ks XMM-Newton/EPIC-pn and 10 ks Rossi X-Ray Timing Explorer observations during a bright phase of its 2002-2003 outburst. An extremely skewed, relativistic Fe Kalpha emission line and ionized disk

  17. Modeling potential hydrochemical responses to climate change and rising CO2 at the Hubbard Brook Experimental Forest using a dynamic biogeochemical model (PnET-BGC)

    Science.gov (United States)

    Afshin Pourmokhtarian; Charles T. Driscoll; John L. Campbell; Katharine. Hayhoe

    2012-01-01

    Dynamic hydrochemical models are useful tools for understanding and predicting the interactive effects of climate change, atmospheric CO2, and atmospheric deposition on the hydrology and water quality of forested watersheds. We used the biogeochemical model, PnET-BGC, to evaluate the effects of potential future changes in temperature,...

  18. Beauty at HERA-B : Measurement of the bb Production Cross Section in pN Collisions at sqrt(s) = 41.6 GeV

    NARCIS (Netherlands)

    Mevius, Maaijke

    2003-01-01

    This thesis reports on the measurement of the bb production cross section using the 2000 dataset of the HERA-B experiment. HERA-B is a fixed target experiment using the 920 GeV protons of the HERA accelerator of DESY, Hamburg. The production cross section of beauty quarks in pN collisions

  19. Selective Catalytic Hydrogenation of Arenols by a Well-Defined Complex of Ruthenium and Phosphorus–Nitrogen PN3–Pincer Ligand Containing a Phenanthroline Backbone

    KAUST Repository

    Li, Huaifeng

    2017-05-30

    Selective catalytic hydrogenation of aromatic compounds is extremely challenging using transition-metal catalysts. Hydrogenation of arenols to substituted tetrahydronaphthols or cyclohexanols has been reported only with heterogeneous catalysts. Herein, we demonstrate the selective hydrogenation of arenols to the corresponding tetrahydronaphthols or cyclohexanols catalyzed by a phenanthroline-based PN3-ruthenium pincer catalyst.

  20. Cu2ZnSnS4@TiO2 p-n heterostructured nanosheet arrays: Controllable hydrothermal synthesis and enhanced visible light-driven photocatalytic activity

    Science.gov (United States)

    Gan, Tian; Li, Yan; Wang, Xiang-Zhuo; Wang, Xiao-Tian; Wang, Cheng-Wei

    2017-06-01

    We have designed and fabricated a novel particle/sheet p-n heterostructural nanosheet arrays of Cu2ZnSnS4@TiO2 via a facile two-step hydrothermal method. The results from characterizations of SEM, TEM, XRD, Raman spectra, XPS, and UV-vis spectrophotometer indicate that p-type Cu2ZnSnS4 (CZTS) nanoparticles were successfully assembled on the vertically oriented TiO2 nanosheet arrays, forming three-dimensional distributed p-n heterostructural film photocatalyst, which could efficiently expand spectral response, promote photoinduced charges separation, and increase the specific surface areas for photocatalytic reaction, and then strengthen samples' visible light-driven photocatalytic activity. Furthermore, we found that the absorption edges of the samples exhibited the red shift from 390 nm to 700 nm with the CZTS deposition time. The results of photocatalytic degradation methyl orange (MO) showed that the new type CZTS@TiO2 p-n heterostructural nanosheet arrays with 24 h hydrothermal reaction revealed the optimal degradation rate of K = 1.2 h-1, about 6.6 times higher than that of the pure TiO2 nanosheet arrays under the same conditions; and also demonstrated an excellent stability and reusability during the cyclic experiments, which would be primarily attributed to optimal loading capacities of CZTS nanoparticles and an adequate built-in electric field at their interfaces of p-n heterostructures.

  1. Tuning of optical and electrical properties of wide band gap Fe:SnO{sub 2}/Li:NiO p-n junctions using 80 MeV oxygen ion beam

    Energy Technology Data Exchange (ETDEWEB)

    Mistry, Bhaumik V.; Joshi, U.S. [Gujarat University, Department of Physics, School of Sciences, Ahmedabad (India); Avasthi, D.K. [Inter University Accelerator Centre, New Delhi (India)

    2016-12-15

    Electrical and optical properties of pristine and swift heavy ion (SHI) irradiated p-n junction diode have been investigated for advanced electronics application. Fe:SnO{sub 2}/Li:NiO p-n junction was fabricated by using pulsed laser deposition on c-sapphire substrate. The optical band gaps of Fe:SnO{sub 2} and Li:NiO films were obtained to be 3.88 and 3.37 eV, respectively. The current-voltage characteristics of the oxide-based p-n junction showed a rectifying behaviour with turn-on voltage of 0.95 V. The oxide-based p-n junction diode was irradiated to 80 MeV O{sup +6} ions with 1 x 10{sup 12} ions/cm{sup 2} fluence. Decrease in grain size due to SHI irradiation is confirmed by the grazing angle X-ray diffraction and atomic force microscopy. In comparison with the pristine p-n junction diode, O{sup +6} ion irradiated p-n junction diode shows the increase of surface roughness and decrease of percentage transmittance in visible region. For irradiated p-n junction diode, current-voltage curve has still rectifying behaviour but exhibits lower turn-on voltage than that of virgin p-n junction diode. (orig.)

  2. Synthesis and physical properties of Cr–P-based intermetallic compounds: Cr{sub 3}P, Cr{sub 3}PC, and Cr{sub 3}PN

    Energy Technology Data Exchange (ETDEWEB)

    Zu, L.; Lin, S. [Key Laboratory of Materials Physics, Institute of Solid State Physics, Chinese Academy of Sciences, Hefei 230031 (China); Tong, P., E-mail: tongpeng@issp.ac.cn [Key Laboratory of Materials Physics, Institute of Solid State Physics, Chinese Academy of Sciences, Hefei 230031 (China); Lin, J.C.; Kan, X.C.; Wang, B.S.; Song, W.H. [Key Laboratory of Materials Physics, Institute of Solid State Physics, Chinese Academy of Sciences, Hefei 230031 (China); Sun, Y.P., E-mail: ypsun@issp.ac.cn [High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei 230031 (China); Key Laboratory of Materials Physics, Institute of Solid State Physics, Chinese Academy of Sciences, Hefei 230031 (China); Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093 (China)

    2015-05-05

    Highlights: • Polycrystalline samples of Cr{sub 3}P, Cr{sub 3}PC, and Cr{sub 3}PN are first synthesized by using solid state reaction method. • A good quality of our samples is verified by the Rietveld refinement and electrical transport measurements. • We present a comprehensive understanding of physical properties of Cr{sub 3}P, Cr{sub 3}PC, and Cr{sub 3}PN. - Abstract: We report the synthesis, crystal structures and electrical/thermal transport properties of polycrystalline Cr{sub 3}PX (X = C, N, and vacancy) compounds. As a result, Cr{sub 3}PC and Cr{sub 3}PN have an orthorhombic crystal structure with space group Cmcm, while Cr{sub 3}P shows a tetragonal structure with space group I−4. All samples show good metallic behavior between 2 and 350 K in the measurement of electrical transport. At the same time, the Fermi-liquid behavior is observed at low temperatures for Cr{sub 3}PC (N) (2–50 K) and Cr{sub 3}P (2–22 K). Based on the fitting results of low-temperature resistivity and specific heat, large Kadowaki–Woods ratio of Cr{sub 3}PC (N) and Cr{sub 3}P were obtained, suggesting a considerably strong electron–electron correlation for all our samples. By analyzing the thermal conductivity data, it is found that the electron thermal conductivity is predominantly stronger than the phonon one at low temperatures for Cr{sub 3}P. As to Cr{sub 3}PC and Cr{sub 3}PN, however, both contributions are comparable in the whole temperature range investigated. Besides, phonon-drag effect was observed in the Seebeck coefficient α(T) curves for all the samples, which may explain the crossover of sign at 70 K in α(T) of Cr{sub 3}PN.

  3. Novel Ag{sub 3}PO{sub 4}/MoO{sub 3}p-n heterojunction with enhanced photocatalytic activity and stability under visible light irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Teng, Wei, E-mail: tengw@just.edu.cn [Department of Environmental and Chemical Engineering, Jiangsu University of Science and Technology, Zhenjiang, 212003 (China); Tan, Xiangjun [Department of Environmental and Chemical Engineering, Jiangsu University of Science and Technology, Zhenjiang, 212003 (China); Li, Xinyong [Key Laboratory of Industrial Ecology and Environmental Engineering and State Key Laboratory of Fine Chemical, School of Environmental Sciences and Technology, Dalian University of Technology, Dalian, 116024 (China); Tang, Yubin [Department of Environmental and Chemical Engineering, Jiangsu University of Science and Technology, Zhenjiang, 212003 (China)

    2017-07-01

    Graphical abstract: Excellent photocatalytic activity and stability are achieved over Ag{sub 3}PO{sub 4}/MoO{sub 3}p-n heterostructure nanocatalyst, which was increased the charge separation efficiencies. - Highlights: • The Ag{sub 3}PO{sub 4}/MoO{sub 3}p-n heterostructure nanocatalyst was synthesized successfully. • The composite nanocatalyst possesses excellent photocatalytic activity and stability. • The effective separation of electron-hole pairs were mainly depend on the inner electric field of p-n heterojunction. - Abstract: Ag{sub 3}PO{sub 4}/MoO{sub 3}p-n heterojunction have been successfully fabricated by using a simple in situ solvent method. SEM, TEM, XRD, XPS and electrochemical techniques were used to study the structural and electrochemical characteristics of the resulting materials. The photocatalytic activity of the obtained composite was tested by the degradation of organic dye (methylene blue) under visible-light irradiation. The photocatalytic activity of Ag{sub 3}PO{sub 4}/MoO{sub 3} remained 92.5% after four recycling runs, which was much higher than that of the pure Ag{sub 3}PO{sub 4} (54%). The obtained results confirm that the novel Ag{sub 3}PO{sub 4}/MoO{sub 3} heterostructure exhibited significantly higher photocatalytic activities and improved stability compared with bare Ag{sub 3}PO{sub 4}. The excellent photocatalytic activity came from the effective separation of the electron-hole pairs under the effect of built-in electric field in the interfacial the of the p-n heterojunction, and then made the holes more available for dyes oxidation.

  4. High Performance Nanostructured Silicon-Organic Quasi p-n Junction Solar Cells via Low-Temperature Deposited Hole and Electron Selective Layer.

    Science.gov (United States)

    Liu, Yuqiang; Zhang, Zhi-Guo; Xia, Zhouhui; Zhang, Jie; Liu, Yuan; Liang, Feng; Li, Yongfang; Song, Tao; Yu, Xuegong; Lee, Shuit-Tong; Sun, Baoquan

    2016-01-26

    Silicon-organic solar cells based on conjugated polymers such as poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) ( PSS) on n-type silicon (n-Si) attract wide interest because of their potential for cost-effectiveness and high-efficiency. However, a lower barrier height (Φb) and a shallow built in potential (Vbi) of Schottky junction between n-Si and PSS hinders the power conversion efficiency (PCE) in comparison with those of traditional p-n junction. Here, a strong inversion layer was formed on n-Si surface by inserting a layer of 1, 4, 5, 8, 9, 11-hexaazatriphenylene hexacarbonitrile (HAT-CN), resulting in a quasi p-n junction. External quantum efficiency spectra, capacitance-voltage, transient photovoltage decay and minority charge carriers life mapping measurements indicated that a quasi p-n junction was built due to the strong inversion effect, resulting in a high Φb and Vbi. The quasi p-n junction located on the front surface region of silicon substrates improved the short wavelength light conversion into photocurrent. In addition, a derivative perylene diimide (PDIN) layer between rear side of silicon and aluminum cathodes was used to block the holes from flowing to cathodes. As a result, the device with PDIN layer also improved photoresponse at longer wavelength. A champion PCE of 14.14% was achieved for the nanostructured silicon-organic device by combining HAT-CN and PDIN layers. The low temperature and simple device structure with quasi p-n junction promises cost-effective high performance photovoltaic techniques.

  5. Signaling pathways coordinating the alkaline pH response confer resistance to the hevein-type plant antimicrobial peptide Pn-AMP1 in Saccharomyces cerevisiae.

    Science.gov (United States)

    Kwon, Youngho; Chiang, Jennifer; Tran, Grant; Giaever, Guri; Nislow, Corey; Hahn, Bum-Soo; Kwak, Youn-Sig; Koo, Ja-Choon

    2016-12-01

    Genome-wide screening of Saccharomyces cerevisiae revealed that signaling pathways related to the alkaline pH stress contribute to resistance to plant antimicrobial peptide, Pn-AMP1. Plant antimicrobial peptides (AMPs) are considered to be promising candidates for controlling phytopathogens. Pn-AMP1 is a hevein-type plant AMP that shows potent and broad-spectrum antifungal activity. Genome-wide chemogenomic screening was performed using heterozygous and homozygous diploid deletion pools of Saccharomyces cerevisiae as a chemogenetic model system to identify genes whose deletion conferred enhanced sensitivity to Pn-AMP1. This assay identified 44 deletion strains with fitness defects in the presence of Pn-AMP1. Strong fitness defects were observed in strains with deletions of genes encoding components of several pathways and complex known to participate in the adaptive response to alkaline pH stress, including the cell wall integrity (CWI), calcineurin/Crz1, Rim101, SNF1 pathways and endosomal sorting complex required for transport (ESCRT complex). Gene ontology (GO) enrichment analysis of these genes revealed that the most highly overrepresented GO term was "cellular response to alkaline pH". We found that 32 of the 44 deletion strains tested (72 %) showed significant growth defects compared with their wild type at alkaline pH. Furthermore, 9 deletion strains (20 %) exhibited enhanced sensitivity to Pn-AMP1 at ambient pH compared to acidic pH. Although several hundred plant AMPs have been reported, their modes of action remain largely uncharacterized. This study demonstrates that the signaling pathways that coordinate the adaptive response to alkaline pH also confer resistance to a hevein-type plant AMP in S. cerevisiae. Our findings have broad implications for the design of novel and potent antifungal agents.

  6. Long-term outcomes after lobectomy for non-small cell lung cancer when unsuspected pN2 disease is found: A National Cancer Data Base analysis.

    Science.gov (United States)

    Yang, Chi-Fu Jeffrey; Kumar, Arvind; Gulack, Brian C; Mulvihill, Michael S; Hartwig, Matthew G; Wang, Xiaofei; D'Amico, Thomas A; Berry, Mark F

    2016-05-01

    There are few studies evaluating whether to proceed with planned resection when a patient with non-small cell lung cancer (NSCLC) unexpectedly is found to have N2 disease at the time of thoracoscopy or thoracotomy. To help guide management of this clinical scenario, we evaluated outcomes for patients who were upstaged to pN2 after lobectomy without induction therapy using the National Cancer Data Base (NCDB). Survival of NSCLC patients treated with lobectomy for clinically unsuspected mediastinal nodal disease (cT1-cT3 cN0-cN1, pN2 disease) from 1998-2006 in the NCDB was compared with "suspected" N2 disease patients (cT1-cT3 cN2) who were treated with chemotherapy with or without radiation followed by lobectomy, using matched analysis based on propensity scores. Unsuspected pN2 disease was found in 4.4% of patients (2047 out of 46,691) who underwent lobectomy as primary therapy for cT1-cT3 cN0-cN1 NSCLC. The 5-year survival was 42%, 36%, 21%, and 28% for patients who underwent adjuvant chemotherapy (n = 385), chemoradiation (n = 504), radiation (n = 300), and no adjuvant therapy (n = 858), respectively. Five-year survival of the entire unsuspected pN2 cohort was worse than survival of 2302 patients who were treated with lobectomy after induction therapy for clinical N2 disease (30% vs 40%; P based analysis suggests that, in the setting of unsuspected pN2 NSCLC, proceeding with lobectomy does not appear to compromise outcomes if adjuvant chemotherapy with or without radiation therapy can be administered following surgery. Copyright © 2016 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.

  7. Sb{sub 2}S{sub 3}:C/CdS p-n junction by laser irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Arato, A. [Facultad de Ingenieria Mecanica y Electrica, Universidad Autonoma de Nuevo Leon, San Nicolas de los Garza, Nuevo Leon (Mexico); Centro de Innovacion, Investigacion y Desarrollo en Ingenieria y Tecnologia-Universidad Autonoma de Nuevo Leon, Apodaca, Nuevo Leon (Mexico); Cardenas, E. [Facultad de Ingenieria Mecanica y Electrica, Universidad Autonoma de Nuevo Leon, San Nicolas de los Garza, Nuevo Leon (Mexico); Shaji, S. [Facultad de Ingenieria Mecanica y Electrica, Universidad Autonoma de Nuevo Leon, San Nicolas de los Garza, Nuevo Leon (Mexico); Centro de Innovacion, Investigacion y Desarrollo en Ingenieria y Tecnologia-Universidad Autonoma de Nuevo Leon, Apodaca, Nuevo Leon (Mexico); O' Brien, J.J.; Liu, J. [Center for Nanoscience, University of Missouri-St. Louis, One University Boulevard, St. Louis, Missouri-63121 (United States); Department of Chemistry and Biochemistry, University of Missouri-St. Louis, One University Boulevard, St. Louis, Missouri-63121 (United States); Castillo, G. Alan; Das Roy, T.K. [Facultad de Ingenieria Mecanica y Electrica, Universidad Autonoma de Nuevo Leon, San Nicolas de los Garza, Nuevo Leon (Mexico); Krishnan, B. [Facultad de Ingenieria Mecanica y Electrica, Universidad Autonoma de Nuevo Leon, San Nicolas de los Garza, Nuevo Leon (Mexico); Centro de Innovacion, Investigacion y Desarrollo en Ingenieria y Tecnologia-Universidad Autonoma de Nuevo Leon, Apodaca, Nuevo Leon (Mexico)], E-mail: bkrishnan@fime.uanl.mx

    2009-02-02

    In this paper, we report laser irradiated carbon doping of Sb{sub 2}S{sub 3} thin films and formation of a p-n junction photovoltaic structure using these films. A very thin carbon layer was evaporated on to chemical bath deposited Sb{sub 2}S{sub 3} thin films of approximately 0.5 {mu}m in thickness. Sb{sub 2}S{sub 3} thin films were prepared from a solution containing SbCl{sub 3} and Na{sub 2}S{sub 2}O{sub 3} at 27 deg. C for 5 h and the films obtained were highly resistive. These C/Sb{sub 2}S{sub 3} thin films were irradiated by an expanded laser beam of diameter approximately 0.5 cm (5 W power, 532 nm Verdi laser), for 2 min at ambient atmosphere. Morphology and composition of these films were analyzed. These films showed p-type conductivity due to carbon diffusion (Sb{sub 2} S{sub 3}:C) by the thermal energy generated by the absorption of laser radiation. In addition, these thin films were incorporated in a photovoltaic structure Ag/Sb{sub 2}S{sub 3}:C/CdS/ITO/Glass. For this, CdS thin film of 50 nm in thickness was deposited on a commercially available ITO coated glass substrate from a chemical bath containing CdCl{sub 2}, sodium citrate, NH{sub 4}OH and thiourea at 70 deg. C . On the CdS film, Sb{sub 2}S{sub 3}/C layers were deposited. This multilayer structure was subjected to the laser irradiation, C/Sb{sub 2}S{sub 3} side facing the beam. The p-n junction formed by p-Sb{sub 2}S{sub 3}:C and n-type CdS showed V{sub oc} = 500 mV and J{sub sc} = 0.5 mA/cm{sup 2} under illumination by a tungsten halogen lamp. This work opens up a new method to produce solar cell structures by laser assisted material processing.

  8. Binding of (/sup 3/H)isradipine (PN 200-110) on smooth muscle cell membranes from different bovine arteries

    Energy Technology Data Exchange (ETDEWEB)

    Pinquier, J.L.; Urien, S.; Chaumet-Riffaud, P.; Comte, A.; Tillement, J.P.

    1988-04-01

    The binding of (/sup 3/H)isradipine ((/sup 3/H)PN 200-110), a new dihydropyridine (DHP) calcium blocker on smooth muscle cell (SMC) membranes from different bovine arteries was saturable with comparable high affinities but different binding site densities (Bmax). The data were fitted to a model that provided a common estimation for the dissociation constant (Kd = 0.46 nM, SD = 0.03) but different Bmax values. Two groups of arteries could be distinguished, large-sized with high Bmax (aorta, 149 fmol/mg, SD = 4; intrapulmonary, 134 fmol/mg, SD = 4) and medium-sized with lower Bmax (mesenteric, 67 fmol/mg, SD = 2; internal carotid, 50 fmol/mg, SD = 2; renal artery, 29 fmol/mg, SD = 2). The Kd values were similar to those previously reported, but the Bmax value on aorta SMC was higher than usually reported with other DHPs, showing that isradipine was a high full antagonist of calcium channel. Our results also suggest that the increase in arterial compliance induced by DHPs will probably be more important on large-sized arteries than on medium-sized arteries because of higher DHP binding.

  9. Doping GaP Core-Shell Nanowire pn-Junctions: A Study by Off-Axis Electron Holography.

    Science.gov (United States)

    Yazdi, Sadegh; Berg, Alexander; Borgström, Magnus T; Kasama, Takeshi; Beleggia, Marco; Samuelson, Lars; Wagner, Jakob B

    2015-06-10

    The doping process in GaP core-shell nanowire pn-junctions using different precursors is evaluated by mapping the nanowires' electrostatic potential distribution by means of off-axis electron holography. Three precursors, triethyltin (TESn), ditertiarybutylselenide, and silane are investigated for n-type doping of nanowire shells; among them, TESn is shown to be the most efficient precursor. Off-axis electron holography reveals higher electrostatic potentials in the regions of nanowire cores grown by the vapor-liquid-solid (VLS) mechanism (axial growth) than the regions grown parasitically by the vapor-solid (VS) mechanism (radial growth), attributed to different incorporation efficiency between VLS and VS of unintentional p-type carbon doping originating from the trimethylgallium precursor. This study shows that off-axis electron holography of doped nanowires is unique in terms of the ability to map the electrostatic potential and thereby the active dopant distribution with high spatial resolution. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Oxide p-n Heterojunction of Cu2O/ZnO Nanowires and Their Photovoltaic Performance

    Directory of Open Access Journals (Sweden)

    Seung Ki Baek

    2013-01-01

    Full Text Available Oxide p-n heterojunction devices consisting of p-Cu2O/n-ZnO nanowires were fabricated on ITO/glass substrates and their photovoltaic performances were investigated. The vertically arrayed ZnO nanowires were grown by metal organic chemical vapor deposition, which was followed by the electrodeposition of the p-type Cu2O layer. Prior to the fabrication of solar cells, the effect of bath pH on properties of the absorber layers was studied to determine the optimal condition of the Cu2O electrodeposition process. With the constant pH 11 solution, the Cu2O layer preferred the (111 orientation, which gave low electrical resistivity and high optical absorption. The Cu2O (pH 11/ZnO nanowire-based solar cell exhibited a higher conversion efficiency of 0.27% than the planar structure solar cell (0.13%, because of the effective charge collection in the long wavelength region and because of the enhanced junction area.

  11. Measurements and analysis of current-voltage characteristic of a pn diode for an undergraduate physics laboratory

    CERN Document Server

    Cataldo, Enrico; Maccarrone, Francesco; Paffuti, Giampiero

    2016-01-01

    We show that in a simple experiment at undergraduate level, suitable to be performed in classes of science and engineering students, it is possible to test accurately, on a popular 1N4148 p-n diode, the range of the junction currents where the Shockley equation model can be considered satisfactory. The experiment benefits from a system of temperature control and data collection driven in a LabVIEW environment. With these tools a large quantity of data can be recorded in the temporal frame of a lab session. Significant deviations of the experimental I-V with respect to the ideal behaviour curve predicted by the Shockley equation are observed, both at low and high current. A better agreement over the entire range is obtained introducing, as is customary, a four parameters model, including a parallel and a series resistance. A new iterative fitting procedure is presented which treats the I-V data of different regimes on the same level, and allows a simultaneous determination of the four parameters for each tempe...

  12. Fabrication of WS2/GaN p-n Junction by Wafer-Scale WS2 Thin Film Transfer

    Science.gov (United States)

    Yu, Yang; Fong, Patrick W. K.; Wang, Shifeng; Surya, Charles

    2016-01-01

    High quality wafer-scale free-standing WS2 grown by van der Waals rheotaxy (vdWR) using Ni as a texture promoting layer is reported. The microstructure of vdWR grown WS2 was significantly modified from mixture of crystallites with their c-axes both parallel to (type I) and perpendicular to (type II) the substrate to large type II crystallites. Wafer-scale transfer of vdWR grown WS2 onto different substrates by an etching-free technique was demonstrated for the first time that utilized the hydrophobic property of WS2 and hydrophilic property of sapphire. Our results show that vdWR is a reliable technique to obtain type-II textured crystallites in WS2, which is the key factor for the wafer-scale etching-free transfer. The transferred films were found to be free of observable wrinkles, cracks, or polymer residues. High quality p-n junctions fabricated by room-temperature transfer of the p-type WS2 onto an n-type GaN was demonstrated with a small leakage current density of 29.6 μA/cm2 at −1 V which shows superior performances compared to the directly grown WS2/GaN heterojunctions. PMID:27897210

  13. Ideal p-n Diode Current Equation for Organic Heterojunction using a Buffer Layer: Derivation and Numerical Study

    Science.gov (United States)

    Kim, SeongMin; Ha, Jaewook; Kim, Jin-Baek

    2016-04-01

    The equation of p-n diode current-voltage (J-V) of an organic heterojunction (HJ) including a hole and electron buffer layer is derived, and its characteristics are numerically simulated based on a polaron-pair model Giebink et al. (Forrest, Phys. Rev. B 82; 1-12, 2010). In particular, the correlation between a fraction of the potential drop for an electron/hole buffer ( δ e - b / δ h - b ) and for a donor (D)/acceptor (A) ( δ D / δ A ) is numerically investigated for J-V curves. As a result, the lowest diode current (DC) is obtained for the condition of δ e - b + δ A ≅ 0 or δ D + δ h - b ≅ 1. It is suggested that it is important to characterize the lowest DC curve for the state of D/A blending with a condition of a fraction of the potential drop ( δ e - b / δ h - b ). Under these circumstances, the transport of holes ( h +) from a DC source at the reverse bias is effectively limited.

  14. PERSPEKTIF KEADILAN DAN KEPASTIAN HUKUM DALAM PUTUSAN PRAPERADILAN NOMOR: 04/Pid.Prap/2015/PN.Jkt.Sel. TAHUN 2015

    Directory of Open Access Journals (Sweden)

    Oktein Josephus Susak

    2016-04-01

    Full Text Available Abstract Pretrial arrangement in the Criminal Procedure Code is a strict rule with a clear limitation. One function of pretrial is to test the validity of the initial arrest and detention as a forced effort on behalf of legislation. Pretrial in the formulation of the Criminal Procedure Code is more directed at administrative oversight. In a pretrial ruling No. 04/Pid.Prap/2015/PN.Jkt.Sel., judges have intruded normative boundaries by extending the authority of a preliminary hearing object includes examining “determination of the suspect”, although not explicitly mentioned in the Criminal Procedure Code provisions. The problem in this research is “How is the existence of Criminal Pretrial Case Decision No. 04/Pid.Prap/2015/PN.Jkt.Sel., viewed from the aspect of justice and the rule of law?”. This research is a normative juridical approach method using the conceptual approach, case approach and the approach of legislation. Based on the findings, it was concluded that the examination in pretrial is a voluntair examination as an effort to actualize the procedural justice, but related  to a quo case, to realize substantial justice the judges act by entering the “determination of the suspect” as an element of the object of new norms in the series Article 77 letter a Criminal Procedure Code into a pretrial authority. This creates legal uncertainty, since it contradicts with the principle of Lex Specialis Derogat Legi Generalis, Noscitur a Sociis principle, Ejusdem Generis principle and the principle of Expressio Unius Exclusio Alterius. With the model of reasoning methods argumentum a'contrario as one of the construction methods of the law against Article 77 letter a Criminal Code, it is known that the “determination of the suspect” is not a pretrial object . The actions of judges had exceeded its authority, and the logic of the law of the judge in the formation of the new norm object element does not include extensive interpretation

  15. Rhodopsin p.N78I dominant mutation causing sectorial retinitis pigmentosa in a pedigree with intrafamilial clinical heterogeneity.

    Science.gov (United States)

    Rivera-De la Parra, David; Cabral-Macias, Jesus; Matias-Florentino, Margarita; Rodriguez-Ruiz, Gabriela; Robredo, Violeta; Zenteno, Juan Carlos

    2013-04-25

    The purpose of this study was to determine the molecular basis of retinitis pigmentosa (RP) in a 4 affected sib-family segregating this retinal phenotype. Affected sibs underwent complete ophthalmologic examination including funduscopic inspection, electroretinogram, fluorescein angiography, visual field measurement, and optical coherence tomography. Both parents were deceased after their sixties and were reported with no visual handicap. Molecular analysis included direct nucleotide sequencing of the rhodopsin gene (RHO), at chromosome 3q21-q24, in DNA from a total of 4 affected sibs. A total of 200 ethnically matched alleles were included as mutation controls. Sector RP was clinically documented in this family. Wide phenotypic variability was observed with visual acuities ranging from 20/20 to 20/200 and variable funduscopic appearance. Molecular analysis disclosed a c.233A>T mutation at RHO exon 1, predicting a missense p.N78I substitution. Even though RP can be caused by mutations in a variety of genes, the RHO gene was chosen to be investigated in this RP family since it has been previously associated to sector disease. This case exemplifies the value of guiding RP molecular analysis based on funduscopic features. Copyright © 2013 Elsevier B.V. All rights reserved.

  16. Suspended p-n junction InGaN/GaN multiple quantum wells device with bottom silver reflector

    Science.gov (United States)

    Gao, Xumin; Li, Xin; Yang, Yongchao; Yuan, Wei; Xu, Yin; Cai, Wei; Wang, Yongjin

    2017-07-01

    In this study, we propose, fabricate, and characterize suspended p-n junction InGaN/GaN multiple quantum wells (MQWs) device with a bottom silver reflector for diverse applications. The suspended device was achieved through a double-side process on the GaN-on-silicon platform and tested by using a micro-reflectance/transmittance setup. When the suspended device operates under the light-emitting diode mode, a fraction of the emitted light reflected by the bottom silver reflector can enter into the air through the top escape cone, leading to improved light extraction efficiency. When the suspended device operates under the photodiode mode, part of the transmitted light can be reflected back by the bottom silver reflector to enhance the photovoltaic effect. The experimental results demonstrate that such suspended device can be used as both transmitter and receiver for visible light communication. And the detecting features even when the suspended structure is under turn-on state, demonstrating a potential realization of light emission and photodetection simultaneously.

  17. Zn doping induced conductivity transformation in NiO films for realization of p-n homo junction diode

    Science.gov (United States)

    Dewan, Sheetal; Tomar, Monika; Tandon, R. P.; Gupta, Vinay

    2017-06-01

    Mixed transition metal oxide, zinc doped NiO, Z n x N i 1 - x O (x = 0, 0.01, 0.02, 0.05, and 0.10), thin films have been fabricated by the RF magnetron sputtering technique in an oxygen deficit ambience at a growth temperature of 400 °C. The present report highlights the effect of Zn doping in NiO thin films on its structural, optical, and electrical properties. Optical transmission enhancement and band gap engineering in a-axis oriented NiO films have been demonstrated via Zn substitution. Hall effect measurements of the prepared samples revealed a transition from p-type to n-type conductivity in NiO at 2% Zn doping. A NiO based transparent p-n homojunction diode has been fabricated successfully, and the conduction mechanism dominating the diode properties is reported in detail. Current-voltage (I-V) characteristics of the homojunction diode are found to obey the Space Charge Limited Conduction mechanism with non-ideal square law behaviour.

  18. Direct observation of the carrier transport process in InGaN quantum wells with a pn-junction

    Science.gov (United States)

    Wu, Haiyan; Ma, Ziguang; Jiang, Yang; Wang, Lu; Yang, Haojun; Li, Yangfeng; Zuo, Peng; Jia, Haiqiang; Wang, Wenxin; Zhou, Junming; Liu, Wuming; Chen, Hong

    2016-11-01

    A new mechanism of light-to-electricity conversion that uses InGaN/GaN QWs with a p-n junction is reported. According to the well established light-to-electricity conversion theory, quantum wells (QWs) cannot be used in solar cells and photodetectors because the photogenerated carriers in QWs usually relax to ground energy levels, owing to quantum confinement, and cannot form a photocurrent. We observe directly that more than 95% of the photoexcited carriers escape from InGaN/GaN QWs to generate a photocurrent, indicating that the thermionic emission and tunneling processes proposed previously cannot explain carriers escaping from QWs. We show that photoexcited carriers can escape directly from the QWs when the device is under working conditions. Our finding challenges the current theory and demonstrates a new prospect for developing highly efficient solar cells and photodetectors. Project supported by the National Natural Science Foundation of China (Grant Nos. 11574362, 61210014, and 11374340) and the Innovative Clean-energy Research and Application Program of Beijing Municipal Science and Technology Commission, China (Grant No. Z151100003515001).

  19. New Chiral P-N Ligands for the Regio- and Stereoselective Pd-Catalyzed Dimerization of Styrene

    Directory of Open Access Journals (Sweden)

    Sergio Castillon

    2011-02-01

    Full Text Available Two new chiral, enantiomerically pure, hybrid P-N ligands, namely (2R,5S-2-phenyl-3-(2-pyridyl-1,3-diaza-2-phosphanicyclo[3,3,0]octan-4-one (1 and (2R,5S-2-phenyl-3-(2-pyridyl-1,3-diaza-2-phosphanicyclo[3,3,0]octane (2, have been synthesized starting from L-proline. The two ligands differ in the presence or not of a carbonyl group in the diazaphosphane ring. Their coordination chemistry towards Pd(II was studied by reacting them with [Pd(CH3Cl(cod]. A different behaviour was observed: ligand 2 shows the expected bidentate chelating behaviour leading to the mononuclear Pd-complex, while ligand 1 acts as a terdentate ligand giving a dinuclear species. The corresponding cationic derivatives were obtained from the palladium neutral complexes, both as mono- and dinuclear derivatives, and tested as precatalysts for styrene dimerization, yielding E-1,3-diphenyl-1-butene regio- and stereoselectively as the sole product. A detailed analysis of the catalytic behaviour is reported.

  20. PnLRR-RLK27, a novel leucine-rich repeats receptor-like protein kinase from the Antarctic moss Pohlia nutans, positively regulates salinity and oxidation-stress tolerance.

    Directory of Open Access Journals (Sweden)

    Jing Wang

    Full Text Available Leucine-rich repeats receptor-like kinases (LRR-RLKs play important roles in plant growth and development as well as stress responses. Here, 56 LRR-RLK genes were identified in the Antarctic moss Pohlia nutans transcriptome, which were further classified into 11 subgroups based on their extracellular domain. Of them, PnLRR-RLK27 belongs to the LRR II subgroup and its expression was significantly induced by abiotic stresses. Subcellular localization analysis showed that PnLRR-RLK27 was a plasma membrane protein. The overexpression of PnLRR-RLK27 in Physcomitrella significantly enhanced the salinity and ABA tolerance in their gametophyte growth. Similarly, PnLRR-RLK27 heterologous expression in Arabidopsis increased the salinity and ABA tolerance in their seed germination and early root growth as well as the tolerance to oxidative stress. PnLRR-RLK27 overproduction in these transgenic plants increased the expression of salt stress/ABA-related genes. Furthermore, PnLRR-RLK27 increased the activities of reactive oxygen species (ROS scavengers and reduced the levels of malondialdehyde (MDA and ROS. Taken together, these results suggested that PnLRR-RLK27 as a signaling regulator confer abiotic stress response associated with the regulation of the stress- and ABA-mediated signaling network.

  1. Comparisons of fission track age-determination and radioactivation analysis among radiation fields. Characteristic values for pneumatic tube, JRR-3M PN2

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, Tatsuro [Kagoshima Univ. (Japan). Faculty of Education; Tomura, Kenji

    1996-01-01

    It is necessary for Fission track age determination and radioactivation analysis to define the energy spectrum of a reactor neutron as the basis for calculating the nuclear reaction rate. This study was made aiming to define the spectrum for PN2 pneumatic tube of No. 3 plant of Japan Atomic Energy Research Institute (JAERI). Characteristics such as conventional flux, cross reaction, neutron temperature and integral fast flux were examined for 3 facilities; JRR-2, JRR-4 and JRR-3M. And the neutron spectrum for each facility was estimated based on the assumptions; Maxwell distribution for thermal neutrons, 1/E for intermediate neutrons and Watt`s formula for fast neutrons. The present results showed that the spectrum for JRR-3M, PN2 was discontinuous in the range from the intermediate to the fast neutron, whereas those for other facilities were found considerably improved. (M.N.)

  2. Selective Hydrogen Generation from Formic Acid with Well-Defined Complexes of Ruthenium and Phosphorus-Nitrogen PN3-Pincer Ligand

    KAUST Repository

    Pan, Yupeng

    2016-04-22

    An unsymmetrically protonated PN3-pincer complex in which ruthenium is coordinated by one nitrogen and two phosphorus atoms was employed for the selective generation of hydrogen from formic acid. Mechanistic studies suggest that the imine arm participates in the formic acid activation/deprotonation step. A long life time of 150 h with a turnover number over 1 million was achieved. Grabbing hold: A PN3-pincer complex was employed for the selective hydrogen generation from formic acid. Mechanistic studies suggest the imine arm participates in the formic acid activation/deprotonation step. A long life time of 150 h with a turnover number over 1 million was achieved. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Fabrication and photoelectric properties of La-doped p-type ZnO nanofibers and crossed p-n homojunctions by electrospinning.

    Science.gov (United States)

    Zhang, H D; Yu, M; Zhang, J C; Sheng, C H; Yan, X; Han, W P; Liu, Y C; Chen, S; Shen, G Z; Long, Y Z

    2015-06-21

    La-doped p-type ZnO nanofibers were successfully synthesized by electrospinning, followed by calcination. The microstructure and morphology of the La-doped ZnO nanofibers were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy. The field effect curve of individual nanofibers confirms that the resulting La-doped ZnO fibers are p-type semiconductors. The doping mechanism is discussed. Furthermore, crossed p-n homojunction nanofibers were also prepared based on electrospun La-doped p-type ZnO and n-type pure ZnO fibers. The current-voltage curve shows the typical rectifying characteristic of a p-n homojunction device. The turn-on voltage appears at about 2.5 V under the forward bias and the reverse current is impassable.

  4. Cross-section and analyzing-power measurements for the sup 2 H(n,pn)n reaction at 189 MeV

    CERN Document Server

    Anderson, B D; Sowinski, J; Baldwin, A R; Franklin, W; Watson, J W; Wissink, S; Wolanski, M; Yang, G; Glöckle, W; Witala, H

    2000-01-01

    We measured cross sections and analyzing powers for the sup 2 H(n,n) sup 2 H and sup 2 H(n,pn)n reactions at 189 MeV at the Indiana University Cyclotron Facility (IUCF). These measurements are designed to search for evidence of three-body forces in the nuclear force and have the advantage that the Coulomb force is not involved. The analyzing-power measurements for the sup 2 H(n,n) sup 2 H reaction are in close agreement with those from the analog sup 2 H(p,p) sup 2 H reaction at nearby energies and do not agree quantitatively with available three-body, Faddeev calculations, either with or without three-body forces included. The sup 2 H(n,pn)n measurements are still under analysis.

  5. Measurement of {sup 27}Al(γ,2pn){sup 24}Na Reaction Cross-sections with 55 -, 60 -, 65 - MeV Bremsstrahlung Employing MCNPX Simulation

    Energy Technology Data Exchange (ETDEWEB)

    Shin, S. G.; Kye, Y.; Cho, M. H. [POSTECH, Pohang (Korea, Republic of); Namkung, W. [Pohang Accelerator Laboratory, Pohang (Korea, Republic of); KIm, G. N.; Kim, K. [Kyungpook National Univ., Daegu (Korea, Republic of); Lee, M. W.; Kang, Y. R. [Dongnam Inst. Of Radiological and Medical Science, Busan (Korea, Republic of)

    2014-05-15

    Aluminum is used for monitoring the photon flux. The photon flux during the activation can be measured by substituting the {sup 27}Al(γ,2pn){sup 24}Na reaction cross-section induced by bremsstrahlung to reactivity equation. Therefore, if this cross-section is more accurate, gamma-ray flux can be measure more accurately. In this work, the {sup 27}Al(γ,2pn){sup 24}Na reaction cross-sections induced by 55 - 65 MeV bremsstrahlung were measured by activation technique at the Pohang Neutron Facility (PNF) which has produced the nuclear data using Time-Of-Flight method and activation technique. In order to get the photon flux, MCNPX was used. These measurement values were compared with the data of Meyer et al (1968)

  6. On the feasibility of multi-polymer, liquid-crystal silica photovoltaics: simulating diodic p-n junctions with ionic gradients

    OpenAIRE

    Puniani, Arjan Singh

    2010-01-01

    Conventional photovoltaic machinery, including traditional silicone panels, fails to address efficiency problems. Recent technological advances suggest less metal-specific reliance, but plastic substrates are bound by cost-inefficiency. Photovoltaic paint effectively dissociates from metal dependency and relies on a combination p-n junction diode principle/thermoelectric effect to generate electrical energy from solar exposure. Replicating the junction is accomplished via multi-polymer layers...

  7. Prognostic value of HPV-mRNA in sentinel lymph nodes of cervical cancer patients with pN0-status

    OpenAIRE

    D?rst, Matthias; Hoyer, Heike; Altgassen, Christoph; Greinke, Christiane; H?fner, Norman; Fishta, Alba; Gajda, Mieczyslaw; Mahnert, Ute; Hillemanns, Peter; Dimpfl, Thomas; Lenhard, Miriam; Petry, K. Ulrich; Runnebaum, Ingo B.; Schneider, Achim

    2015-01-01

    Up to 15% of patients with cervical cancer and pN0-status develop recurrent-disease. This may be due to occult metastatic spread of tumor cells. We evaluated the use of human-papillomavirus-(HPV)-mRNA as a molecular marker for disseminated tumor cells to predict the risk of recurrence. For this prospective, multi-center prognostic study, 189 patients free of lymphnode metastases by conventional histopathology could be analyzed. All patients underwent complete lymphadenectomy. Of each sentinel...

  8. Pre-targeted immunodetection in glioma patients: tumour localization and single-photon emission tomography imaging of [[sup 99m]Tc ]PnAO-biotin

    Energy Technology Data Exchange (ETDEWEB)

    Paganelli, G. (INB-CNR, Milan Univ. (Italy). Dept. of Nuclear Medicine Scientific Inst. H San Raffaele, Milan (Italy)); Magnani, P. (INB-CNR, Milan Univ. (Italy). Dept. of Nuclear Medicine Scientific Inst. H San Raffaele, Milan (Italy)); Zito, F. (INB-CNR, Milan Univ. (Italy). Dept. of Nuclear Medicine Scientific Inst. H San Raffaele, Milan (Italy)); Lucignani, G. (INB-CNR, Milan Univ. (Italy). Dept. of Nuclear Medicine Scientific Inst. H San Raffaele, Milan (Italy)); Sudati, F. (INB-CNR, Milan Univ. (Italy). Dept. of Nuclear Medicine Scientific Inst. H San Raffaele, Milan (Italy)); Truci, G. (Div. of Neurology, Milan Univ. (Italy) Scientific Inst. H San Raffaele, Milan (Italy)); Motti, E. (Div. of Neurosurgery, Milan Univ. (Italy) Scientific Inst. H San Raffaele, Milan (Italy)); Terreni, M. (Dept. of Pathology, Scientific Inst. H San Raffaele, Milan (Italy)); Pollo, B. (Dept. of Pathology, Scientific Inst. G. Besta, Milan (Italy)); Giovanelli, M. (Div. of Neurosurgery, Milan

    1994-04-01

    We have developed a three-step pre-targeting method using the avidin-biotin system. The rationale of this technique consists in vivo labelling of biotinylated MoAbs targeted onto tumour deposits, when most of the unbound antibodies have been cleared from the bloodstream as avidin-bound complexes. The anti-tenascin MoAb BC2, specific for the majority of gliomas, was biotinylated and 1 mg was administered i.v. in 20 patients with histologically documented cerebral lesions. After 24-36 h, 5 mg avidin was injected i.v. followed 24 h later by a third i.v. injection of 0.2 mg PnAO-biotin labelled with 15-20 mCi technetium-99m. No evidence of toxicity was observed. Whole-body biodistribution was measured at 20 min, 3 h and 5 h post-injection. [[sup 99m]Tc]PnAO-biotin had a fast blood clearance and was primarily excreted through the biliary system. A dedicated single-photon emission tomography system was used to acquire brain tomographic images 1-2 h after the administration of [[sup 99m]Tc]PnAO-biotin. Tumours were detected in 15/18 glioma patients with a tumour to non-tumour ratio of up 14:1. This three-step method, based on the sequential adminsitration of anti-tenascin MoAb BC2, avidin and [[sup 99m]Tc]PnAO-biotin, can support computed tomography or magnetic resonance imaging for the diagnosis and follow-up of patients with glioma. (orig./MG)

  9. On-chip photonic system using suspended p-n junction InGaN/GaN multiple quantum wells device and multiple waveguides

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Yongjin, E-mail: wangyj@njupt.edu.cn; Zhu, Guixia; Gao, Xumin; Yang, Yongchao; Yuan, Jialei; Shi, Zheng; Zhu, Hongbo [Grünberg Research Centre, Nanjing University of Posts and Telecommunications, Nanjing 210003 (China); Cai, Wei [Grünberg Research Centre, Nanjing University of Posts and Telecommunications, Nanjing 210003 (China); School of Computer Engineering, Nanjing Institute of Technology, Nanjing 211167 (China)

    2016-04-18

    We propose, fabricate, and characterize the on-chip integration of suspended p-n junction InGaN/GaN multiple quantum wells (MQWs) device and multiple waveguides on the same GaN-on-silicon platform. The integrated devices are fabricated via a wafer-level process and exhibit selectable functionalities for diverse applications. As the suspended p-n junction InGaN/GaN MQWs device operates under a light emitting diode (LED) mode, part of the light emission is confined and guided by the suspended waveguides. The in-plane propagation along the suspended waveguides is measured by a micro-transmittance setup. The on-chip data transmission is demonstrated for the proof-of-concept photonic integration. As the suspended p-n junction InGaN/GaN MQWs device operates under photodiode mode, the light is illuminated on the suspended waveguides with the aid of the micro-transmittance setup and, thus, coupled into the suspended waveguides. The guided light is finally sensed by the photodiode, and the induced photocurrent trace shows a distinct on/off switching performance. These experimental results indicate that the on-chip photonic integration is promising for the development of sophisticated integrated photonic circuits in the visible wavelength region.

  10. The effect of self-depleting in UV photodetector based on simultaneously fabricated TiO2/NiO pn heterojunction and Ni/Au composite electrode

    Science.gov (United States)

    Zhang, Dezhong; Liu, Chunyu; Xu, Ruiliang; Yin, Bo; Chen, Yu; Zhang, Xindong; Gao, Fengli; Ruan, Shengping

    2017-09-01

    A novel dark self-depleting ultraviolet (UV) photodetector based on a TiO2/NiO pn heterojunction was demonstrated and exhibited lower dark current (I dark) and noise. Both the NiO layer and Ni/Au composite electrode were fabricated by a smart, one-step oxidation method which was first employed in the fabrication of the UV photodetector. In dark, the depleted pn heterojunction structure effectively reduced the majority carrier density in TiO2/NiO films, demonstrating a high resistance state and contributing to a lower I dark of 0.033 nA, two orders of magnitude lower than that of the single-material devices. Under UV illumination, the interface self-depleting effect arising from the dissociation and accumulation of photogenerated carriers was eliminated, ensuring loss-free responsivity (R) and a remarkable specific detectivity (D*) of 1.56 × 1014 cm Hz1/2 W-1 for the optimal device. The device with the structure of ITO/TiO2/NiO/Au was measured to prove the mechanisms of interface self-depleting in dark and elimination of the depletion layer under UV illumination. Meanwhile, shortened decay time was achieved in the pn heterojunction UV photodetector. This suggests that the self-depleting devices possess the potential to further enhance photodetection performance.

  11. Li14P2O3N6 and Li7PN4: Computational study of two nitrogen rich crystalline LiPON electrolyte materials

    Science.gov (United States)

    Al-Qawasmeh, Ahmad; Holzwarth, N. A. W.

    2017-10-01

    Two lithium oxonitridophosphate materials are computationally examined and found to be promising solid electrolytes for possible use in all solid-state batteries having metallic Li anodes - Li14P2O3N6 and Li7PN4. The first principles simulations are in good agreement with the structural analyses reported in the literature for these materials and the computed total energies indicate that both materials are stable with respect to decomposition into binary and ternary products. The computational results suggest that both materials are likely to form metastable interfaces with Li metal. The simulations also find both materials to have Li ion migration activation energies comparable or smaller than those of related Li ion electrolyte materials. Specifically, for Li7PN4, the experimentally measured activation energy can be explained by the migration of a Li ion vacancy stabilized by a small number of O2- ions substituting for N3- ions. For Li14P2O3N6, the activation energy for Li ion migration has not yet been experimentally measured, but simulations predict it to be smaller than that measured for Li7PN4.

  12. Doping control of GaAsPN alloys by molecular beam epitaxy for monolithic III-V/Si tandem solar cells

    Science.gov (United States)

    Yamane, Keisuke; Sato, Kento; Sekiguchi, Hiroto; Okada, Hiroshi; Wakahara, Akihiro

    2017-09-01

    This paper presents intentional doping of n- and p-type GaAs0.19P0.76N0.05 alloys by molecular beam epitaxy, followed by rapid thermal annealing (RTA). Sulfur and magnesium were respectively used as n- and p-type dopants. The carrier concentrations were controllable between 1017 and 1019 cm-3 by adjusting the dopant cell temperature. It was revealed that Hall mobility of the n-type GaAsPN alloys was increased by the RTA process compared to as-grown ones, whereas no significant difference was apparent in the p-type alloys. It is believed that improvement of the conduction band spatial uniformity was mainly responsible for the Hall mobility increase of the n-type GaAsPN alloys by RTA. Finally, a p-i-n GaAsPN diode structure was grown on n-type GaP substrates. A current-voltage characteristic showed a typical rectifying curve with a built-in voltage of 1.8 V and an ideality factor of 1.45. The reverse saturation current was estimated to be less than 10 nA/cm2.

  13. Detection of Salmonella in Foods Using a Reference PN-ISO Method and an Alternative Method Based on Loop-mediated Isothermal Amplification Coupled with Bioluminescence.

    Science.gov (United States)

    Sarowska, Jolanta; Frej-Mądrzak, Magdalena; Jama-Kmiecik, Agnieszka; Kilian, Anna; Teryks-Wołyniec, Dorota; Choroszy-Król, Irena

    2016-01-01

    Salmonella, one of the primary indicators of food safety, is a common cause of food poisoning of an epidemic nature around the world. These microorganisms can colonize the gastrointestinal tract of both people and animals, and next contaminate not only eggs, milk, meat and dairy products, but also vegetables, fruit, grains and even spices. The aim of this study was to analyze the frequency of detection of Salmonella spp. in food samples using a reference PN-ISO method and an alternative method based on loop-mediated isothermal amplification (LAMP) coupled with bioluminescence. Food samples were obtained in cooperation with the State Sanitary-Epidemiological Station in Wrocław. Dairy products, meat, fish, pastry and confectionery, vegetables, herbs and spices were analyzed. The food samples were examined using a standard culturing method according to PN-ISO 6579:2003 for Salmonella spp. and an alternative method based on the isothermal amplification and bioluminescence phenomenon using the 3M MDS device. In 399 tested food samples in 8 materials, using both the reference and the alternative LAMP-based method, the presence of salmonella was confirmed. The results obtained show the 100% sensitivity, specificity and accuracy of the presented alternative, LAMP-based technique compared to the reference PN-ISO method. The alternative method using isothermal amplification and bioluminescence makes it possible to detect Salmonella in foods in a much shorter time than the referential culturing method.

  14. Interface pn junction arrays with high yielded grown p-Si microneedles by vapor-liquid-solid method at low temperature

    Science.gov (United States)

    Islam, Md. Shofiqul; Ishida, Makoto

    2015-01-01

    In this work we report the fabrication and investigation of the properties of interface pn junction arrays formed at the interface of vertically aligned p-Si microneedles and n-Si substrate. Arrays of boron doped p-Si microneedles were grown on n-Si substrate with the maximum yield of 100% by Au-catalysed vapor-liquid-solid (VLS) growth using in-situ doping with the mixed gas of Si2H6 and B2H6 at temperature less than 700 °C, which is low as compared to the temperature (1100 °C) required by diffusion process to dope Si microneedles after VLS growth. The physical dimension (diameter, length) and position of these p-Si microneedles can be controlled. The variation of growth rate, diameter, conductivity, impurity concentration and hole mobility of these p-Si microneeedles were investigated with the variation of boron doping. The pn junctions, formed with p-Si microneedles having different diameters, were found to exhibit standard diode characteristics. These pn junction embedded Si microneedle arrays might be potential candidate in sensor area applications. Again, low temperature processing would be compatible to integrate these junction arrays with other circuitry on a chip. This work provides one step forward to realize more sophisticated vertical active devices (BJT, MOSFET, etc) with Si microneedles.

  15. Design of high breakdown voltage vertical GaN p-n diodes with high-K/low-K compound dielectric structure for power electronics applications

    Science.gov (United States)

    Du, Jiangfeng; Li, Zhenchao; Liu, Dong; Bai, Zhiyuan; Liu, Yang; Yu, Qi

    2017-11-01

    In this work, a vertical GaN p-n diode with a high-K/low-K compound dielectric structure (GaN CD-VGD) is proposed and designed to achieve a record high breakdown voltage (BV) with a low specific on-resistance (Ron,sp). By introducing compound dielectric structure, the electric field near the p-n junction interface is suppressed due to the effects of high-K passivation layer, and a new electric field peak is induced into the n-type drift region, because of a discontinuity of electrical field at the interface of high-K and low-K layer. Therefore the distribution of electric field in GaN p-n diode becomes more uniform and an enhancement of breakdown voltage can be achieved. Numerical simulations demonstrate that GaN CD-VGD with a BV of 10650 V and a Ron,sp of 14.3 mΩ cm2, resulting in a record high figure-of-merit of 8 GW/cm2.

  16. TiO2 coated CuO nanowire array: Ultrathin p-n heterojunction to modulate cationic/anionic dye photo-degradation in water

    Science.gov (United States)

    Scuderi, Viviana; Amiard, Guillaume; Sanz, Ruy; Boninelli, Simona; Impellizzeri, Giuliana; Privitera, Vittorio

    2017-09-01

    We report the photocatalytic efficiency of CuO nanowires covered with a thin TiO2 film, studied by dyes degradation in water. The CuO nanowires were synthesized on Cu foils by thermal oxidation. A subsequent TiO2 deposition (7, 15, 30, 50 nm thick) was performed by atomic layer deposition, developing an ultrathin p-n heterojunction. A structural characterization was obtained by X-ray diffraction analysis, scanning and transmission electron microscopies equipped with energy dispersive x-ray analysis. The photocatalytic activity of the investigated materials was tested by the degradation of a cationic (methylene blue) or anionic (methyl orange). The relevance of the reported results was discussed in relation with the effects of the ultrathin p-n TiO2/CuO heterojunction. The two semiconductors are in intimate connection increasing the exposed surface and only TiO2 is directly in contact with water. This allowed to study systematically the effect of the electric filed generated by the p-n junction on the interface TiO2/liquid and therefore to modulate cationic/anionic dyes photo-degradation in water.

  17. On the performance of selenium rich lead-salt heterostructure lasers with remote p-n junction

    Energy Technology Data Exchange (ETDEWEB)

    Rosman, R.; Katzir, A.; Norton, P.; Bachem, K.H.; Preier, H.M.

    1987-01-01

    In order to increase the operating temperature of lasers emitting in the mid-IR, various lead chalcogenide diode lasers have been fabricated and examined: Pb/sub 0.95/Sn/sub 0.05/Se/PbSe and PbSe/PbS double heterostructure and funnel-type Pb/sub 1-x/Eu/sub x/Se lasers (the Eu content in the cladding layers increased steadily from x = 0.01 near the active layer up to x = 0.03). All the lasers were grown by molecular beam epitaxy on PbSe substrates. The p-n junctions were located not on the (lattice mismatched) interfaces, but at various distances (2000-6000 A) within the confinement layer. The highest operation temperatures (CW operation up to 165 K at 5.3 ..mu..m and pulsed operation up to 220 K at 4.4 ..mu..m) were attained by the PbSe/Pb/sub 1-x/Eu/sub x/Se funnel-type laser. The experimental results were compared to theoretical computer-assisted calculations, which accounted in a self-consistent way for the distributions of light, charge carriers, and temperature within the lasers. The agreement between theory and measurements for the temperature dependence of the threshold current and wavelength and for maximal operation temperatures was quite good. The authors found that the main contributions to the current come from interface recombination and from overbarrier leakage of nonconfined carriers (both minority and majority). Ways to improve the lasers are discussed.

  18. Putusan Bebas Atas Dakwaan Tindak Pidana Lingkungan Hidup: Analisis Putusan No. 781/pid/b/2009/PN.CBN.

    Directory of Open Access Journals (Sweden)

    Hidayatulloh .

    2016-10-01

    Full Text Available Abstract: Acquittal on Accusation of Environmental Crime: Analysis of Verdict Number No. 781/Pid/B/2009/PN.Cbn. The number of industries has increasead rapidly and caused some problems in the environment. With the help of science and technology, most of industries produce toxic waste which is one of the issues of the environmental crime. This paper will analyse the verdict of Cibinong District Court on accusation of environmental crime to Lee Sang Book, the Director of PT. Roselia Texindo. The company working in textile industry was indicted that he has done water pollution in the River Cikuda, Bogor because he has thrown the toxic waste to the river produced by its industry. The verdict is really interesting because the panel of judges have finally decided that Lee Sang Book is not guilty. Based on facts of the trial, he doesn’t break a law to do the environmental crime which was indicted according to the Law Number 23 Year 2007 in Living Environment. Cibinong District Attorney has submitted the unqualified evidence in examination of waste toxic in laboratorium. Furthermore most witnesses and expert witnessed have argued that Lee Sang Book and PT. Roselia Texindo are innocence and have followed the rule. Abstrak: Jumlah industri telah meningkat dengan cepat dan menyebabkan beberapa persoalan lingkungan. Dengan dukungan ilmu pengetahuan dan teknologi, banyak industri menghasilkan limbah berbahaya yang merupakan salah satu isu tindak pidana lingkungan. Tulisan ini menganalisis putusan Pengadilan Negeri Cibinong atas dakwaan tindak pidana lingkungan kepada Lee Sang Book, Direktur PT. Roselia Texindo. Perusahaan yang bergerak di bidang tekstil ini didakwa melakukan pencemaran air sungai Cikuda, Bogor karena membuat limbah kimia hasil proses industri. Pada akhirnya Majelis Hakim memutus bahwa Lee Sang Book tidak bersalah. Berdasarkan fakta-fakta persidangan, ia tidak terbukti melakukan tindak pidana lingkungan yang didakwakan berdasarkan Undang

  19. Respective prognostic value of genomic grade and histological proliferation markers in early stage (pN0 breast carcinoma.

    Directory of Open Access Journals (Sweden)

    Fabien Reyal

    Full Text Available BACKGROUND: Genomic grade (GG is a 97-gene signature which improves the accuracy and prognostic value of histological grade (HG in invasive breast carcinoma. Since most of the genes included in the GG are involved in cell proliferation, we performed a retrospective study to compare the prognostic value of GG, Mitotic Index and Ki67 score. METHODS: A series of 163 consecutive breast cancers was retained (pT1-2, pN0, pM0, 10-yr follow-up. GG was computed using MapQuant Dx(R. RESULTS: GG was low (GG-1 in 48%, high (GG-3 in 31% and equivocal in 21% of cases. For HG-2 tumors, 50% were classified as GG-1, 18% as GG-3 whereas 31% remained equivocal. In a subgroup of 132 ER+/HER2- tumors GG was the most significant prognostic factor in multivariate Cox regression analysis adjusted for age and tumor size (HR = 5.23, p = 0.02. CONCLUSIONS: In a reference comprehensive cancer center setting, compared to histological grade, GG added significant information on cell proliferation in breast cancers. In patients with HG-2 carcinoma, applying the GG to guide the treatment scheme could lead to a reduction in adjuvant therapy prescription. However, based on the results observed and considering (i the relatively close prognostic values of GG and Ki67, (ii the reclassification of about 30% of HG-2 tumors as Equivocal GG and (iii the economical and technical requirements of the MapQuant micro-array GG test, the availability in the near future of a PCR-based Genomic Grade test with improved performances may lead to an introduction in clinical routine of this test for histological grade 2, ER positive, HER2 negative breast carcinoma.

  20. Respective prognostic value of genomic grade and histological proliferation markers in early stage (pN0) breast carcinoma.

    Science.gov (United States)

    Reyal, Fabien; Bollet, Marc A; Caly, Martial; Gentien, David; Carpentier, Sabrina; Peyro-Saint-Paul, Hélène; Pierga, Jean-Yves; Cottu, Paul; Dieras, Véronique; Sigal-Zafrani, Brigitte; Vincent-Salomon, Anne; Sastre-Garau, Xavier

    2012-01-01

    Genomic grade (GG) is a 97-gene signature which improves the accuracy and prognostic value of histological grade (HG) in invasive breast carcinoma. Since most of the genes included in the GG are involved in cell proliferation, we performed a retrospective study to compare the prognostic value of GG, Mitotic Index and Ki67 score. A series of 163 consecutive breast cancers was retained (pT1-2, pN0, pM0, 10-yr follow-up). GG was computed using MapQuant Dx(R). GG was low (GG-1) in 48%, high (GG-3) in 31% and equivocal in 21% of cases. For HG-2 tumors, 50% were classified as GG-1, 18% as GG-3 whereas 31% remained equivocal. In a subgroup of 132 ER+/HER2- tumors GG was the most significant prognostic factor in multivariate Cox regression analysis adjusted for age and tumor size (HR = 5.23, p = 0.02). In a reference comprehensive cancer center setting, compared to histological grade, GG added significant information on cell proliferation in breast cancers. In patients with HG-2 carcinoma, applying the GG to guide the treatment scheme could lead to a reduction in adjuvant therapy prescription. However, based on the results observed and considering (i) the relatively close prognostic values of GG and Ki67, (ii) the reclassification of about 30% of HG-2 tumors as Equivocal GG and (iii) the economical and technical requirements of the MapQuant micro-array GG test, the availability in the near future of a PCR-based Genomic Grade test with improved performances may lead to an introduction in clinical routine of this test for histological grade 2, ER positive, HER2 negative breast carcinoma.

  1. High-resolution measurements of the exited states (n,pn, (n,dn C-12 cross sections

    Directory of Open Access Journals (Sweden)

    Pillon M.

    2017-01-01

    Full Text Available Measurements of C12 cross sections for the excited states (n,p0 up to (n,p4 and (n,d0, (n,d1 have been carried out. The Van de Graaff neutron generator of the EC-JRC-IRMM laboratory has been used for these measurements. A very thin tritiated target (263 μg/cm2 was employed with deuteron beams energies impinging on the target in the range 2.5–4.0 MeV. Neutrons in the range 18.9–20.7 MeV were produced with an intrinsic energy spread of 0.2–0.25% FWHM. With such narrow neutron energy spread, using a high energy resolution device such as a single crystal diamond detector, several peaks from the outgoing charged particles produced by the (n,pn, (n,dn and also (n,α0 reactions appear in the pulse height spectrum. The peaks can be identified using the reaction Q-values. The diamond detector used for these measurements has shown an intrinsic energy resolution lower than 0.9% FWHM. The analysis of the peaks has permitted to derive the partial carbon reaction cross sections for several excited states. The results are presented in this paper with the associated uncertainties and they are compared with different versions of TENDL compilation when these data are available (e.g. versions 2009, 2010, 2011 and 2015 and also with experimental results available in the EXFOR database.

  2. Integrated Advanced Microwave Sounding Unit-A (AMSU-A). Performance Verification Report: METSAT Phase Locked Oscillator Assembly, P/N 1348360-1, S/N's F09

    Science.gov (United States)

    Pines, D.

    1999-01-01

    This is the Performance Verification Report, METSAT (Meteorological Satellites) Phase Locked Oscillator Assembly, P/N 1348360-1, S/N F09 and F10, for the Integrated Advanced Microwave Sounding Unit-A (AMSU-A).

  3. Hydrogen passivation of n+p and p+n heteroepitaxial InP solar cell structures

    Science.gov (United States)

    Chatterjee, B.; Ringel, S. A.; Hoffman, R., Jr.

    1995-01-01

    High-efficiency, heteroepitaxial (HE) InP solar cells, grown on GaAs, Si or Ge substrates, are desirable for their mechanically strong, light-weight and radiation-hard properties. However, dislocations, caused by lattice mismatch, currently limit the performance of the HE cells. This occurs through shunting paths across the active photovoltaic junction and by the formation of deep levels. In previous work we have demonstrated that plasma hydrogenation is an effective and stable means to passivate the electrical activity of dislocations in specially designed HE InP test structures. In this work, we present the first report of successful hydrogen passivation in actual InP cell structures grown on GaAs substrates by metalorganic chemical vapor deposition (MOCVD). We have found that a 2 hour exposure to a 13.56 MHz hydrogen plasma at 275 C reduces the deep level concentration in HE n+n InP cell structures from as-grown values of approximately 10(exp 15)/cm(exp -3), down to 1-2 x 10(exp 13)/cm(exp -3). The deep levels in the p-type base region of the cell structure match those of our earlier p-type test structures, which were attributed to dislocations or related point defect complexes. All dopants were successfully reactivated by a 400 C, 5 minute anneal with no detectable activation of deep levels. I-V analysis indicated a subsequent approximately 10 fold decrease in reverse leakage current at -1 volt reverse bias, and no change in the forward biased series resistance of the cell structure which indicates complete reactivation of the n+ emitter. Furthermore, electrochemical C-V profiling indicates greatly enhanced passivation depth, and hence hydrogen diffusion, for heteroepitaxial structures when compared with identically processed homoepitaxial n+p InP structures. An analysis of hydrogen diffusion in dislocated InP will be discussed, along with comparisons of passivation effectiveness for n+p versus p+n heteroepitaxial cell configurations. Preliminary hydrogen

  4. The Upper Limit to the Theoretical Efficiency of P-N Homojunction and Interfacial Layer Heterojunction Solar Cells.

    Science.gov (United States)

    Spitzer, Mark Bradley

    The physical mechanisms governing photovoltaic energy conversion in p-n homojunction and interfacial layer heterojunction (ILH) solar cells are examined. The usefulness of minority carrier mirrors (MCM) in such cells is studied by solving the minority carrier diffusion equation in the n- and p-type quasi-neutral regions of the cell, with boundary conditions representing MCM's at the ends of these regions. In this formalism, the MCM is considered to be an interfacial plane having zero surface recombination velocity. Non -zero values are also considered. It is shown that the MCM improves the open circuit voltage of the solar cell when it is located within a diffusion length of the junction between the n- and p-type regions. The effect of the MCM diminishes as the distance between it and the junction increases. The above analysis is applied to the direct gap materials CuInSe(,2) (E = 1.0eV) and GaAs (E = 1.43eV). It is shown that the theoretical upper limit to the conversion efficiency for devices employing MCM's on the front and back is approximately 26% for a CuInSe(,2) cell of width 2 microns. The analysis is also applied to cells made from silicon. A cell thickness of approximately 300 microns is necessary to absorb all the light owing to the indirect bandgap of silicon, yet the solar cell must be made thin in order to attain the maximum effect of the MCM's. A concept of internal light trapping is discussed; this trapping causes the light to undergo multiple reflections within the thin cell. By solving the minority carrier diffusion equation with appropriate generation function, it is shown that the upper limit to the efficiency is approximately 27%, for a cell of 15 microns in width. The ILH solar cell is examined. A model describing current transport in the ILH cell is discussed and applied to the MIS solar cell. A new type of solar cell, the back surface MIS cell, is considered. The model is applied to this type of cell and the efficiency is calculated. The ILH

  5. Unconventional Pn wave tomography of the Western Mediterranean region and the Gulf of Cadiz. Constraints on plausible locations of major future and past historical earthquakes.

    Science.gov (United States)

    Beghoul, Noureddine; Mezioud-Saich, Amira; Said Oucherif, Mohamed

    2017-04-01

    Selected Pn arrival times extracted from the ISC data, from 1964 to present, are used in an unconventional Pn wave seismic tomography, to map with a much improved resolution, the lateral mantle lid velocity variations in the Western Mediterranean region and the Gulf of Cadiz. In a classical tomography study, one defines an initial lithosphere model, determined by fitting a line over all Pn travels times. Its slope and corresponding intercept allows defining an average Pn velocity and an average Moho depth. The average crustal velocity has been fixed to 6.4 km/s; residuals correspond to the difference between times read at the stations and the ray theoretical times, computed from this pre-determined initial lithosphere model. This initial model corresponds to a regional travel time, sampling broad tectonic provinces, with huge velocity variations. Therefore, the residuals projection, lead to poor resolutions of the mantle lid velocity and Moho depths variations. In the present study first neat observational travel times are established for the 22 major Mediterranean Basin physiographic regions. Second, better ray theoretical times are quantified through this set of pre-determined lithospheres polygons. The obtained residuals are corrected for several effects: (1) the station topography, (2) the Moho depth variations from the source to the receiver, (3) the source depth using a simple efficient approach, and (4) the oceanic and/or continental context of the source and/or station location. As a result residuals have by far, less scatter, and are more meaningfully representative of the lateral velocity variations. This process confines in a much narrower intervals the variations of the sought variables: mantle lid velocity variations in the different polygons and stations delays. A strong correlation is observed between the mapped lateral velocity, Moho depths variations, and the tectonic features observed at the surface. The most important new observations are: (a) a

  6. Anafilaksi Sırasındaki Kusma Sonrası Gastrik İçeriğin Aspirasyonuna Bağlı Kimyasal Pnömonit

    Directory of Open Access Journals (Sweden)

    Özlem Erçen Diken

    2017-08-01

    Full Text Available Anafilaksi sırasında görülebilen kusma sırasında gastrik içeriğin aspirasyonu ile kimyasal pnömonit gelişebilmektedir. Majör bir aspirasyon olduysa solunum yetmezliğine kadar giden bulgular görülür. Kısa zamanda solunum yetmezliği gelişimi ve kısa zamanda klinik ve radyolojik iyileşme gibi, kimyasal pnömoniti aspirasyon pnömonisinden ayıran bazı farklılıklar mevcuttur. Olgumuzu, anafilaksi sırasında kusma sonrası gastrik içerik aspirasyonu ve buna bağlı gelişen kimyasal pnömonit tablosu görülen bir olgu olarak, nadir ve önemli bir durum olması nedeni ile sunuyoruz. Yirmi altı yaşında kadın hastada, sultamisilin ve metamizol tedavisinden sonra anafilaktik reaksiyon gelişmişti. Bu sırada kusma görülen olguda gastrik içerik aspirasyonu gelişmişti. Nefes darlığı ve satürasyon düşüklüğü ile acilimize başvurdu. Olgu acilde görüldüğünde siyanotik, terli, dispneik ve takipneikti. Solunum desteği ihtiyacı olabileceği nedeni ile yoğun bakıma alındı. Akciğer grafisinde sağda belirgin olmak üzere bilateral bazallarda infiltrasyon mevcuttu. Oksijen tedavisi, solunum egzersizi, ekspektoran tedavi, postüral drenaj ile takip edilen olguda, periferik oksijen satürasyonu %90’ın üzerine çıktı. Kısa sürede düzelme nedeniyle ileri invazif işleme (bronkoskopi vb. gerek duyulmadı. Radyolojik olarak birinci günde iyi yanıt alındı. Anafilaksi sırasında kusma görülebileceği akılda tutulmalı ve bu sırada gastrik içerik aspirasyonundan koruyucu önlemler alınmalıdır. Gastrik içerik aspirasyonunun solunum yetmezliğine kadar gidebilecek ciddi seyirli olabileceği unutulmamalı, olgular yakın takip edilmelidir. Klinik, tedavi ve komplikasyonların kimyasal pnömonitte aspirasyon pnömonisinden farklı olduğu da hatırlanmalıdır.

  7. Characterization of vertical GaN p-n diodes and junction field-effect transistors on bulk GaN down to cryogenic temperatures

    Science.gov (United States)

    Kizilyalli, I. C.; Aktas, O.

    2015-12-01

    There is great interest in wide-bandgap semiconductor devices and most recently in vertical GaN structures for power electronic applications such as power supplies, solar inverters and motor drives. In this paper the temperature-dependent electrical behavior of vertical GaN p-n diodes and vertical junction field-effect transistors fabricated on bulk GaN substrates of low defect density (104 to 106 cm-2) is described. Homoepitaxial MOCVD growth of GaN on its native substrate and the ability to control the doping in the drift layers in GaN have allowed the realization of vertical device architectures with drift layer thicknesses of 6 to 40 μm and net carrier electron concentrations as low as 1 × 1015 cm-3. This parameter range is suitable for applications requiring breakdown voltages of 1.2 kV to 5 kV. Mg, which is used as a p-type dopant in GaN, is a relatively deep acceptor (E A ≈ 0.18 eV) and susceptible to freeze-out at temperatures below 200 K. The loss of holes in p-GaN has a deleterious effect on p-n junction behavior, p-GaN contacts and channel control in junction field-effect transistors at temperatures below 200 K. Impact ionization-based avalanche breakdown (BV > 1200 V) in GaN p-n junctions is characterized between 77 K and 423 K for the first time. At higher temperatures the p-n junction breakdown voltage improves due to increased phonon scattering. A positive temperature coefficient in the breakdown voltage is demonstrated down to 77 K; however, the device breakdown characteristics are not as abrupt at temperatures below 200 K. On the other hand, contact resistance to p-GaN is reduced dramatically above room temperature, improving the overall device performance in GaN p-n diodes in all cases except where the n-type drift region resistance dominates the total forward resistance. In this case, the electron mobility can be deconvolved and is found to decrease with T -3/2, consistent with a phonon scattering model. Also, normally-on vertical junction

  8. The effects of shell layer morphology and processing on the electrical and photovoltaic properties of silicon nanowire radial p+-n+ junctions

    Science.gov (United States)

    Wang, Xin; Ke, Yue; Kendrick, Chito E.; Weng, Xiaojun; Shen, Haoting; Kuo, Mengwei; Mayer, Theresa S.; Redwing, Joan M.

    2015-04-01

    Single wire p+-n+ radial junction nanowire solar cell devices were fabricated by low pressure chemical vapor deposition of n+ silicon shell layers on p+ silicon nanowires synthesized by vapor-liquid-solid growth. The n+-shell layers were deposited at two growth temperatures (650 °C and 950 °C) to study the impact of shell crystallinity on the device properties. The n-type Si shell layers deposited at 650 °C were polycrystalline and resulted in diodes that were not rectifying. A pre-coating anneal at 950 °C in H2 improved the structural quality of the shell layers and yielded diodes with a dark saturation current density of 3 × 10-5 A cm-2. Deposition of the n-type Si shell layer at 950 °C resulted in epitaxial growth on the nanowire core, which lowered the dark saturation current density to 3 × 10-7 A cm-2 and increased the solar energy conversion efficiency. Temperature-dependent current-voltage measurements demonstrated that the 950 °C coated devices were abrupt junction p+-n+ diodes with band-to-band tunneling at high reverse-bias voltage, while multi-step tunneling degraded the performance of devices fabricated with a 950 °C anneal and 650 °C coating. The higher trap density of the 950 °C annealed 650 °C coated devices is believed to arise from the polycrystalline nature of the shell layer coating, which results in an increased density of dangling bonds at the p+-n+ junction interface.

  9. In situ Ni-doping during cathodic electrodeposition of hematite for excellent photoelectrochemical performance of nanostructured nickel oxide-hematite p-n junction photoanode

    Energy Technology Data Exchange (ETDEWEB)

    Phuan, Yi Wen, E-mail: phuan.yi.wen@monash.edu [School of Engineering, Chemical Engineering Discipline, Monash University Malaysia, Jalan Lagoon Selatan, Bandar Sunway, Selangor DE 47500 (Malaysia); Ibrahim, Elyas, E-mail: meibr2@student.monash.edu [School of Engineering, Chemical Engineering Discipline, Monash University Malaysia, Jalan Lagoon Selatan, Bandar Sunway, Selangor DE 47500 (Malaysia); Chong, Meng Nan, E-mail: Chong.Meng.Nan@monash.edu [School of Engineering, Chemical Engineering Discipline, Monash University Malaysia, Jalan Lagoon Selatan, Bandar Sunway, Selangor DE 47500 (Malaysia); Sustainable Water Alliance, Advanced Engineering Platform, Monash University Malaysia, Jalan Lagoon Selatan, Bandar Sunway, Selangor DE 47500 (Malaysia); Zhu, Tao, E-mail: zhu.tao@monash.edu [School of Engineering, Chemical Engineering Discipline, Monash University Malaysia, Jalan Lagoon Selatan, Bandar Sunway, Selangor DE 47500 (Malaysia); Lee, Byeong-Kyu, E-mail: bklee@ulsan.ac.kr [Department of Civil and Environmental Engineering, University of Ulsan, Nam-gu, Daehakro 93, Ulsan 680-749 (Korea, Republic of); Ocon, Joey D., E-mail: jdocon@up.edu.ph [Laboratory of Electrochemical Engineering (LEE), Department of Chemical Engineering, University of the Philippines Diliman, Quezon City 1101 (Philippines); Chan, Eng Seng, E-mail: chan.eng.seng@monash.edu [School of Engineering, Chemical Engineering Discipline, Monash University Malaysia, Jalan Lagoon Selatan, Bandar Sunway, Selangor DE 47500 (Malaysia)

    2017-01-15

    Highlights: • NiO-hematite p-n junction photoanodes were fabricated via an in situ Ni-doping. • The fundamental mechanism of Ni{sup 2+} ions involved was elucidated. • The optimum Ni dopant was 25 M% for the highest photocurrent density. • It exhibited an excellent photoelectrochemical performance of 7-folds enhancement. - Abstract: Nanostructured nickel oxide-hematite (NiO/α-Fe{sub 2}O{sub 3}) p-n junction photoanodes synthesized from in situ doping of nickel (Ni) during cathodic electrodeposition of hematite were successfully demonstrated. A postulation model was proposed to explain the fundamental mechanism of Ni{sup 2+} ions involved, and the eventual formation of NiO on the subsurface region of hematite that enhanced the potential photoelectrochemical water oxidation process. Through this study, it was found that the measured photocurrent densities of the Ni-doped hematite photoanodes were highly dependent on the concentrations of Ni dopant used. The optimum Ni dopant at 25 M% demonstrated an excellent photoelectrochemical performance of 7-folds enhancement as compared to bare hematite photoanode. This was attributed to the increased electron donor density through the p-n junction and thus lowering the energetic barrier for water oxidation activity at the optimum Ni dopant concentration. Concurrently, the in situ Ni-doping of hematite has also lowered the photogenerated charge carrier transfer resistance as measured using the electrochemical impedance spectroscopy. It is expected that the fundamental understanding gained through this study is helpful for the rational design and construction of highly efficient photoanodes for application in photoelectrochemical process.

  10. Single- and multi-foils {sup 27}Al(p,3pn){sup 24}Na activation technique for monitoring the intensity of high-energy beams

    Energy Technology Data Exchange (ETDEWEB)

    Curioni, A. [CERN, 1211 Geneva 23 (Switzerland); Politecnico di Milano, Department of Energy, 20156 Milan (Italy); Froeschl, R.; Glaser, M. [CERN, 1211 Geneva 23 (Switzerland); Iliopoulou, E. [CERN, 1211 Geneva 23 (Switzerland); Medical Physics Laboratory, School of Medicine, Aristotle University of Thessaloniki (Greece); La Torre, F.P. [CERN, 1211 Geneva 23 (Switzerland); Pozzi, F., E-mail: fabio.pozzi@cern.ch [CERN, 1211 Geneva 23 (Switzerland); Ravotti, F.; Silari, M. [CERN, 1211 Geneva 23 (Switzerland)

    2017-06-21

    This paper discusses an experimental study of the spallation reaction {sup 27}Al(p,3pn){sup 24}Na in Al foils exposed to 24 GeV c{sup −1} protons, in the context of monitoring the intensity of multi-GeV proton beams through foil activation techniques. Since this reaction is sensitive to secondary neutrons and other energetic secondary hadrons, it is important to evaluate the impact of the foil thickness on the calculation of the beam intensity. This effect is determined experimentally using a stack of Al foils of varying thickness. The experimental results are then compared to Monte Carlo simulations.

  11. Colonic GLP-2 is not sufficient to promote jejunal adaptation in a PN-dependent rat model of human short bowel syndrome

    DEFF Research Database (Denmark)

    Koopmann, Matthew C; Liu, Xiaowen; Boehler, Christopher J

    2009-01-01

    -dependent rat model of SBS. METHODS: Rats underwent jugular catheter placement and a 60% jejunoileal resection + cecectomy with jejunoileal anastomosis or transection control surgery. Rats were maintained exclusively with PN and killed at 4 hours to 12 days. A nonsurgical group served as baseline. Bowel growth...... and digestive capacity were assessed by mucosal mass, protein, DNA, histology, and sucrase activity. Plasma insulin-like growth factor I (IGF-I) and bioactive glucagon-like peptide 2 (GLP-2) were measured by radioimmunoassay. RESULTS: Jejunum cellularity changed significantly over time with resection...

  12. Integrated Advanced Microwave Sounding Unit-A (AMSU-A). Performance Verification Report: METSAT (S/N 108) AMSU-A1 Receiver Assemblies, P/N 1356429-1 S/N F05 and P/N 1356409-1 S/N F05

    Science.gov (United States)

    Haigh, R.; Krimchansky, S. (Technical Monitor)

    2000-01-01

    This is the Performance Verification Report, METSAT (S/N 108) AMSU-A1 Receiver Assemblies P/N 1356429-1 S/N F05 and P/N 1356409-1 S/N F05, for the Integrated Advanced Microwave Sounding Unit-A (AMSU-A). The ATP for the AMSU-A Receiver Subsystem, AE-26002/6A, is prepared to describe in detail the configuration of the test setups and the procedures of the tests to verify that the receiver subsystem meets the specifications as required either in the AMSU-A Instrument Performance and Operation Specifications, S-480-80, or in AMSU-A Receiver Subsystem Specifications, AE-26608, derived by the Aerojet System Engineering. Test results that verify the conformance to the specifications demonstrate the acceptability of that particular receiver subsystem.

  13. Detection of sites of infection in mice using {sup 99m}Tc-labeled PN{sub 2}S-PEG conjugated to UBI and {sup 99m}Tc-UBI: a comparative biodistribution study

    Energy Technology Data Exchange (ETDEWEB)

    Melendez-Alafort, Laura [Department of Pharmaceutical Sciences, University of Padua, 35131 Padova (Italy)], E-mail: lmalafort@yahoo.com; Nadali, Anna; Pasut, Gianfranco; Zangoni, Elena [Department of Pharmaceutical Sciences, University of Padua, 35131 Padova (Italy); De Caro, Raffaele [Department of Anatomy and Physiology, University of Padua, 35131 Padova (Italy); Cariolato, Luca [Department of Pharmaceutical Sciences, University of Padua, 35131 Padova (Italy); Giron, Maria Cecilia [Department of Pharmacology and Anesthesiology, University of Padua, 35131 Padova (Italy); Castagliuolo, Ignazio [Department of Histology, Microbiology and Medical Biotechnologies, University of Padua, 35131 Padova (Italy); Veronese, Francesco M.; Mazzi, Ulderico [Department of Pharmaceutical Sciences, University of Padua, 35131 Padova (Italy)

    2009-01-15

    The antimicrobial peptide ubiquicidin (UBI) directly labeled with technetium-99m ({sup 99m}Tc) has recently been shown to be specifically taken up at sites of infection; however, its chemical structure is not well defined. To address this problem, the aim of the present study was to label UBI using poly(ethyleneglycol)-N-(N-(3-diphenylphosphinopropionyl)glycyl) -S-tritylcysteine ligand (PEG-PN{sub 2}S) in order to compare its ability to detect infection sites with that of {sup 99m}Tc-UBI. Methods: The PN{sub 2}S-PEG-UBI conjugate was prepared and labeled with {sup 99m}Tc, and its radiochemical purity was subsequently assessed. The stability of the conjugate to cysteine challenge and dilution with both saline solution and phosphate buffer was determined and serum stability and protein binding were also assessed. In vivo studies were carried out in healthy mice to study the biodistribution of {sup 99m}Tc-PN{sub 2}S-PEG-UBI and its precursor {sup 99m}Tc-PN{sub 2}S-PEG and in infected mice to compare the uptakes of {sup 99m}Tc-UBI and {sup 99m}Tc-PN{sub 2}S-PEG-UBI at the site of infection using scintigraphic imaging and ex vivo tissue counting. Results: {sup 99m}Tc-PN{sub 2}S-PEG-UBI was obtained with high radiochemical purity (98{+-}1%) and high stability. The amphiphilic nature of the conjugate leads to a tendency to form micellar aggregates that explain the high protein binding values obtained. Biodistribution studies in mice showed low renal clearance followed by a predominant reticuloendothelial system clearance that limits its application in the abdominal area. Statistical analysis revealed no significant difference between {sup 99m}Tc-UBI and {sup 99m}Tc-PN{sub 2}S-PEG-UBI uptake in infected mouse thigh, and the site of infection was clearly visualized using scintigraphic imaging. Conclusions: {sup 99m}Tc-PN{sub 2}S-PEG-UBI proved to be as effective as {sup 99m}Tc-UBI in detecting sites of infection; however, the well-defined chemical structure of {sup 99m}Tc-PN

  14. Integrated Advanced Microwave Sounding Unit-A (AMSU-A). Performance Verification Report: AMSU-A1 Antenna Drive Subsystem, PN 1331720-2, S/N 106

    Science.gov (United States)

    Luu, D.

    1999-01-01

    This is the Performance Verification Report, AMSU-A1 Antenna Drive Subsystem, P/N 1331720-2, S/N 106, for the Integrated Advanced Microwave Sounding Unit-A (AMSU-A). The antenna drive subsystem of the METSAT AMSU-A1, S/N 106, P/N 1331720-2, completed acceptance testing per A-ES Test Procedure AE-26002/lD. The test included: Scan Motion and Jitter, Pulse Load Bus Peak Current and Rise Time, Resolver Reading and Position Error, Gain/ Phase Margin, and Operational Gain Margin. The drive motors and electronic circuitry were also tested at the component level. The drive motor test includes: Starting Torque Test, Motor Commutation Test, Resolver Operation/ No-Load Speed Test, and Random Vibration. The electronic circuitry was tested at the Circuit Card Assembly (CCA) level of production; each test exercised all circuit functions. The transistor assembly was tested during the W3 cable assembly (1356941-1) test.

  15. Ag-bridged Ag2O nanowire network/TiO2 nanotube array p-n heterojunction as a highly efficient and stable visible light photocatalyst.

    Science.gov (United States)

    Liu, Chengbin; Cao, Chenghao; Luo, Xubiao; Luo, Shenglian

    2015-03-21

    A unique Ag-bridged Ag2O nanowire network/TiO2 nanotube array p-n heterojunction (Ag-Ag2O/TiO2 NT) was fabricated by simple electrochemical method. Ag nanoparticles were firstly electrochemically deposited onto the surface of TiO2 NT and then were partly oxidized to Ag2O nanowires while the rest of Ag mother nanoparticles were located at the junctions of Ag2O nanowire network. The Ag-Ag2O/TiO2 NT heterostructure exhibited strong visible-light response, effective separation of photogenerated carriers, and high adsorption capacity. The integration of Ag-Ag2O self-stability structure and p-n heterojunction permitted high and stable photocatalytic activity of Ag-Ag2O/TiO2 NT heterostructure photocatalyst. Under 140-min visible light irradiation, the photocatalytic removal efficiency of both dye acid orange 7 (AO7) and industrial chemical p-nitrophenol (PNP) over Ag-Ag2O/TiO2 NT reached nearly 100% much higher than 17% for AO7 or 13% for PNP over bare TiO2 NT. After 5 successive cycles under 600-min simulated solar light irradiation, Ag-Ag2O/TiO2 NT remained highly stable photocatalytic activity. Copyright © 2014 Elsevier B.V. All rights reserved.

  16. Van der Waals epitaxial growth and optoelectronics of large-scale WSe2/SnS2vertical bilayer p-n junctions.

    Science.gov (United States)

    Yang, Tiefeng; Zheng, Biyuan; Wang, Zhen; Xu, Tao; Pan, Chen; Zou, Juan; Zhang, Xuehong; Qi, Zhaoyang; Liu, Hongjun; Feng, Yexin; Hu, Weida; Miao, Feng; Sun, Litao; Duan, Xiangfeng; Pan, Anlian

    2017-12-04

    High-quality two-dimensional atomic layered p-n heterostructures are essential for high-performance integrated optoelectronics. The studies to date have been largely limited to exfoliated and restacked flakes, and the controlled growth of such heterostructures remains a significant challenge. Here we report the direct van der Waals epitaxial growth of large-scale WSe 2 /SnS 2 vertical bilayer p-n junctions on SiO 2 /Si substrates, with the lateral sizes reaching up to millimeter scale. Multi-electrode field-effect transistors have been integrated on a single heterostructure bilayer. Electrical transport measurements indicate that the field-effect transistors of the junction show an ultra-low off-state leakage current of 10 -14 A and a highest on-off ratio of up to 10 7 . Optoelectronic characterizations show prominent photoresponse, with a fast response time of 500 μs, faster than all the directly grown vertical 2D heterostructures. The direct growth of high-quality van der Waals junctions marks an important step toward high-performance integrated optoelectronic devices and systems.

  17. Low Dark-Current, High Current-Gain of PVK/ZnO Nanoparticles Composite-Based UV Photodetector by PN-Heterojunction Control

    Directory of Open Access Journals (Sweden)

    Sang-Won Lee

    2016-01-01

    Full Text Available We propose a solution-processable ultraviolet (UV photodetector with a pn-heterojunction hybrid photoactive layer (HPL that is composed of poly-n-vinylcarbazole (PVK as a p-type polymer and ZnO nanoparticles (NPs as an n-type metal oxide. To observe the effective photo-inducing ability of the UV photodetector, we analyzed the optical and electrical properties of HPL which is controlled by the doping concentration of n-type ZnO NPs in PVK matrix. Additionally, we confirmed that the optical properties of HPL dominantly depend on the ZnO NPs from the UV-vis absorption and the photoluminescence (PL spectral measurements. This HPL can induce efficient charge transfer in the localized narrow pn-heterojunction domain and increases the photocurrent gain. It is essential that proper doping concentration of n-type ZnO NPs in polymer matrix is obtained to improve the performance of the UV photodetector. When the ZnO NPs are doped with the optimized concentration of 3.4 wt.%, the electrical properties of the photocurrent are significantly increased. The ratio of the photocurrent was approximately 103 higher than that of the dark current.

  18. In situ preparation of Si p-n junctions and subsequent surface preparation for III-V heteroepitaxy in MOCVD ambient

    Science.gov (United States)

    Paszuk, Agnieszka; Dobrich, Anja; Koppka, Christian; Brückner, Sebastian; Duda, Marek; Kleinschmidt, Peter; Supplie, Oliver; Hannappel, Thomas

    2017-04-01

    III-V integration on active Si-bottom cells promises not only high-efficiency multi-junction solar cells but also lower production costs. In situ preparation of an adequate Si p-n junction in metalorganic chemical vapor deposition ambient is challenging, particularly since the final Si surface should be atomically well-ordered to enable low-defect III-V nucleation. Precisely, a single-domain Si(100) surface with double layer steps needs to be prepared in order to suppress antiphase disorder in subsequently grown III-V layer structures on top of the Si p-n junction. We first investigate the formation of a n+-type collector in Si(100) as a result of annealing in tertiarybutylphosphine (TBP) or tertiarybutylarsine (TBAs) ambient. We illustrate how the n-type doping concentrations and their depth profiles depend on the essential preparation parameters, such as precursor partial pressures, exposure and annealing time, as well as reactor pressure. Subsequently, by applying in situ reflectance anisotropy spectroscopy, we find that exposure of Si(100) to TBP or TBAs leads to atomic disorder on the surface. Further, we apply an additional annealing step without precursor supply leading to predominantly (1×2) reconstructed Si(100) surfaces, which are suitable for subsequent low-defect III-V growth.

  19. Influence of Front and Back Contacts on Photovoltaic Performances of p-n Homojunction Si Solar Cell: Considering an Electron-Blocking Layer

    Directory of Open Access Journals (Sweden)

    Md. Feroz Ali

    2017-01-01

    Full Text Available In this simultion work, the effect of front and back contacts of p-n homojunction Si solar cell with an electron-blocking layer (EBL has been studied with the help of a strong solar cell simulator named AMPS-1D (analysis of microelectronic and photonic structures one dimensional. Without the effect of these contact parameters, low solar cell efficiency has been observed. Fluorine-doped tin oxide (FTO with high work function (5.45 eV has been used as the front contact to the proposed solar cell. Zinc (Zn metal which has a work function of 4.3 eV has been used as the back contact of the proposed model. With FTO as the front contact and Zn as the back contact, the optimum efficiency of 29.275% (Voc = 1.363 V, Jsc = 23.747 mA/cm2, FF = 0.905 has been observed. This type of simple Si-based p-n homojunction solar cell with EBL of high efficiency has been proposed in this paper.

  20. Structural and optical studies of GaN pn-junction with AlN buffer layer grown on Si (111) by RF plasma enhanced MBE

    Energy Technology Data Exchange (ETDEWEB)

    Yusoff, Mohd Zaki Mohd; Hassan, Zainuriah; Woei, Chin Che; Hassan, Haslan Abu; Abdullah, Mat Johar [Nano-Optoelectronics Research and Technology Laboratory School of Physics, Universiti Sains Malaysia, 11800 Penang, Malaysia and Department of Applied Sciences Universiti Teknologi MARA (UiTM) 13500 Permatang Pauh, Penang (Malaysia); Department of Applied Sciences Universiti Teknologi MARA (UiTM) 13500 Permatang Pauh, Penang (Malaysia)

    2012-06-29

    GaN pn-junction grown on silicon substrates have been the focus in a number of recent reports and further effort is still necessary to improve its crystalline quality for practical applications. GaN has the high n-type background carrier concentration resulting from native defects commonly thought to be nitrogen vacancies. In this work, we present the growth of pn-junction of GaN on Si (111) substrate using RF plasma-enhanced molecular beam epitaxy (MBE). Both of the layers show uniformity with an average thickness of 0.709 {mu}m and 0.095 {mu}m for GaN and AlN layers, respectively. The XRD spectra indicate that no sign of cubic phase of GaN are found, so it is confirmed that the sample possessed hexagonal structure. It was found that all the allowed Raman optical phonon modes of GaN, i.e. the E2 (low), E1 (high) and A1 (LO) are clearly visible.

  1. Synthesis and enhanced photoelectrocatalytic activity of p-n junction Co{sub 3}O{sub 4}/TiO{sub 2} nanotube arrays

    Energy Technology Data Exchange (ETDEWEB)

    Dai Gaopeng, E-mail: dgp20028@hotmail.com [Department of Chemical engineering and Food Science, Hubei University of Arts and Science, Xiangyang 441053 (China); Liu Suqin [Department of Chemical engineering and Food Science, Hubei University of Arts and Science, Xiangyang 441053 (China); Liang Ying [Department of Chemical engineering and Food Science, Hubei University of Arts and Science, Xiangyang 441053 (China); Key laboratory of catalysis and materials science of the State Ethnic Affairs Commission and Ministry of Education, South-Central University for Nationalities, Wuhan 430074 (China); Luo Tianxiong [Department of Chemical engineering and Food Science, Hubei University of Arts and Science, Xiangyang 441053 (China)

    2013-01-01

    Highlights: Black-Right-Pointing-Pointer Co{sub 3}O{sub 4}/TiO{sub 2} nanotube arrays (NTs) were prepared by an impregnating-deposition-decompostion method treatment. Black-Right-Pointing-Pointer Co{sub 3}O{sub 4}/TiO{sub 2} NTs exhibit high photoelectrocatalytic (PEC) activity. Black-Right-Pointing-Pointer The high PEC activity was attribute to the formation of p-n junction between Co{sub 3}O{sub 4} and TiO{sub 2}. - Abstract: Co{sub 3}O{sub 4}/TiO{sub 2} nanotube arrays (NTs) were prepared by depositing Co{sub 3}O{sub 4} nanoparticles (NPs) on the tube wall of the self-organized TiO{sub 2} NTs using an impregnating-deposition-decompostion method. The prepared samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and UV-vis absorption spectroscopy. The photoelectrocatalytic (PEC) activity is evaluated by degradation of methyl orange (MO) aqueous solution. The prepared Co{sub 3}O{sub 4}/TiO{sub 2} NTs exhibit much higher PEC activity than TiO{sub 2} NTs due to the p-n junction formed between Co{sub 3}O{sub 4} and TiO{sub 2}.

  2. Extraordinary improvement of gas-sensing performances in SnO2 nanofibers due to creation of local p-n heterojunctions by loading reduced graphene oxide nanosheets.

    Science.gov (United States)

    Lee, Jae-Hyoung; Katoch, Akash; Choi, Sun-Woo; Kim, Jae-Hun; Kim, Hyoun Woo; Kim, Sang Sub

    2015-02-11

    We propose a novel approach to improve the gas-sensing properties of n-type nanofibers (NFs) that involves creation of local p-n heterojunctions with p-type reduced graphene oxide (RGO) nanosheets (NSs). This work investigates the sensing behaviors of n-SnO2 NFs loaded with p-RGO NSs as a model system. n-SnO2 NFs demonstrated greatly improved gas-sensing performances when loaded with an optimized amount of p-RGO NSs. Loading an optimized amount of RGOs resulted in a 20-fold higher sensor response than that of pristine SnO2 NFs. The sensing mechanism of monolithic SnO2 NFs is based on the joint effects of modulation of the potential barrier at nanograin boundaries and radial modulation of the electron-depletion layer. In addition to the sensing mechanisms described above, enhanced sensing was obtained for p-RGO NS-loaded SnO2 NFs due to creation of local p-n heterojunctions, which not only provided a potential barrier, but also functioned as a local electron absorption reservoir. These mechanisms markedly increased the resistance of SnO2 NFs, and were the origin of intensified resistance modulation during interaction of analyte gases with preadsorbed oxygen species or with the surfaces and grain boundaries of NFs. The approach used in this work can be used to fabricate sensitive gas sensors based on n-type NFs.

  3. Near-Infrared and Ultraviolet Photodetector Based on p-n Homojunction of Undoped and Phosphorus-Doped Zinc Oxide Nanorods.

    Science.gov (United States)

    Tuico, Anthony; Copa, Vernalyn; Ferrolino, John Paul; Vergara, Christopher Jude; Abrenica, Jefferson; Salvador, Arnel; Somintac, Armando

    2016-06-01

    The application of a p-n homojunction based on zinc oxide (ZnO) nanorods as photodetector is presented in this study. The homojunctions were grown via chemical bath deposition for 6, 9, and 12 hours per layer of the junction. X-ray diffraction and scanning electron micrographs confirmed the material composition, structure, and morphology of the grown device. Current-voltage (I-V) measurements were done to verify the diode-like behavior of the ZnO p-n homojunction. Upon illumination, it is observed through I-V curves and through photocurrent measurements that the fabricated device is sensitive to ultraviolet and near-infrared light, respectively. The peak sensitivities in the photocurrent spectrum were found tunable based on the observed red shift as the length of the nanorods is increased. In addition to this, upon applying a positive voltage bias, the response of the device was observed to enhance by 5 orders of magnitude. In general, the device was successfully proven to have a great potential for applications in photodetection.

  4. Synthesis and visible-light-driven photocatalytic activity of p-n heterojunction Ag2O/NaTaO3 nanocubes

    Science.gov (United States)

    Yang, Songbo; Xu, Dongbo; Chen, Biyi; Luo, Bifu; Yan, Xu; Xiao, Lisong; Shi, Weidong

    2016-10-01

    The constructing of p-n heterojunction photocatalytic system has received much attention in environmental purification and hydrogen generation from water. In this study, an efficient visible-light-driven p-n heterojunction Ag2O/NaTaO3 was successfully prepared by chemical precipitation method at room temperature. It showed an enhanced photocatalytic activity for the degradation of rhodamine B (RhB) under visible-light irradiation, much higher than those of either individual Ag2O or NaTaO3. The reactive species scavenger results indicated the superoxide anion radicals (rad O2-) played key roles in RhB decoloration. From the experimental results and the relative band gap position of these semiconductors, a detailed possible photocatalytic mechanism of the Ag2O/NaTaO3 heterojunction under visible light was proposed. The enhancement of the photocatalytic activity was attributed to the interfacial electronic interaction between NaTaO3 and Ag2O and the high migration efficiency of photogenerated carriers.

  5. Optoelectronic properties of p-n and p-i-n heterojunction devices prepared by electrodeposition of n-ZnO on p-Si

    Science.gov (United States)

    Rakhshani, A. E.

    2010-11-01

    The importance of silicon based optoelectronic devices is due to the well developed silicon technology and its potential for device integration. ZnO/Si light emitting diodes reported in the literature are based mainly on ZnO films grown by the vapor-phase techniques. Electrodeposition, a cost-effective and simple method, has not been explored adequately for the fabrication of such devices. In this study, ZnO films were electrodeposited on the (100) plane of highly B-doped p-Si substrates. Heterojunction devices (p-n and p-i-n) were constructed and characterized by means of current-voltage, capacitance-voltage, photocurrent spectroscopy, photoluminescence, and electroluminescence measurements. Electrodeposition yields compact films with a native donor density ˜1017 cm-3. Diffusion of boron from Si into ZnO, during an annealing process, yields graded p-n junctions with enhanced electroluminescence. Devices exhibit a reasonably good photoresponse in the ultraviolet-blue range. The absorption of subband gap photons in ZnO shows an Urbach tail with a characteristic energy of 115 meV. The absorption and emission of light involves two prominent defect levels in ZnO, namely, L1 and E1.

  6. Integrated Advanced Microwave Sounding Unit-A (AMSU-A). Performance Verification Report, METSAT (S/N:107) AMSU-A1 Receiver Assemblies: P/N 1356429-1, S/N:F04, P/N 1356409-1,S/N F04

    Science.gov (United States)

    Pines, D.

    1999-01-01

    This is the Performance Verification Report, METSAT (S/N: 107) AMSU-A1 Receiver Assemblies, P/N 1356429-1, SIN: F04, P/N 1356409- 1, S/N: F04, for the Integrated Advanced Microwave Sounding Unit-A (AMSU-A). The AMSU-A receiver subsystem comprises two separated receiver assemblies; AMSU-A1 and AMSU-A2 (P/N 1356441-1). The AMSU-A1 receiver contains 13 channels and the AMSU-A2 receiver 2 channels. The AMSU-A receiver assembly is further divided into two parts; AMSU-A I - I (P/N 13 5 6429- 1) and AMSU-A 1 -2 (P/N 1356409-1), which contain 9 and 4 channels, respectively. The AMSU-A receiver subsystem is located in between the antenna and signal processing subsystems of the AMSU-A instrument and comprises the RF and IF components from isolators to attenuators. It receives the RF signals from the antenna subsystem, down-converts the RF signals to IF signals, amplifies and defines the IF signals to proper power level and frequency bandwidth as specified for each channel, and inputs the IF signals to the signal processing subsystem. The test reports for the METSAT AMSU-A receiver subsystem are prepared separately for Al and A2 receivers so that each receiver stands alone during integration of instruments into the spacecraft. This test report presents the test data of the N4ETSAT AMSU-A1 Flight Model No. 4 (FM-4) receiver subsystem. The tests are performed per the Acceptance Test Procedure (ATP) for the AMSU-A Receiver Subsystem, AE-26002/6A. The functional performance tests are conducted either at the component or subsystem level. While the component-level tests are performed over the entire operating temperature range predicted by thermal analysis, most subsystem-level tests are conducted at ambient temperature only. Key performances (bandpass characteristics and noise figure) of the receiver subsystem are verified over the operating temperature.

  7. Thalidomide for the treatment of chronic refractory pruritus.

    Science.gov (United States)

    Sharma, Divya; Kwatra, Shawn G

    2016-02-01

    Pruritus is a common and often times difficult to treat symptom in many dermatologic and systemic diseases. For pruritus with an inflammatory or autoimmune origin, therapies such as topical corticosteroids and antihistamines are often initiated. However, in the case that these and additional systemic therapies are ineffective, thalidomide, an immunomodulator and neuromodulator, may be a useful alternative treatment. Considerable relief of chronic pruritus has been demonstrated with thalidomide in case reports, case series, and controlled trials. Double-blind controlled studies demonstrated thalidomide's efficacy as an antipruritic agent in patients with uremic pruritus, primary biliary cirrhosis, and prurigo nodularis. In case reports, case series, and open-label trials, thalidomide significantly reduced pruritus associated with conditions such as actinic prurigo and paraneoplastic pruritus. Because of variations in study design and evaluation of antipruritic effect, it is difficult to fully understand thalidomide's role based on the evidence described to date in the medical literature. In this review, we provide an overview of the reported findings and evaluate thalidomide's utility in managing refractory pruritus in the context of its adverse risk profile. We propose that thalidomide can be an alternative or combination antipruritic treatment for patients who do not obtain enough relief from conservative therapy. Copyright © 2015 American Academy of Dermatology, Inc. Published by Elsevier Inc. All rights reserved.

  8. Characterization of AlGaN/GaN p-n diodes with selectively regrown n-AlGaN by metal-organic chemical-vapor deposition and its application to GaN-based bipolar transistors

    Science.gov (United States)

    Xing, H.; DenBaars, S. P.; Mishra, U. K.

    2005-06-01

    p-n junctions formed by selective regrowth of n-(Al)GaN on p-GaN were characterized by I -V measurements and secondary-ion-mass spectrometry (SIMS). Regrown p-n diodes of high quality with low leakage currents were achieved, comparable to as-grown GaN p-n diodes, by optimizing the regrowth conditions and structures. SIMS revealed a sharp Mg profile at the regrowth interface. It confirms that these regrown structures are suitable to serve as emitter-base junctions for GaN-based bipolar transistors. This study offers us insight into analyzing n-p-n GaN homojunction bipolar transistors with a current gain of 10 and Al0.05GaN /GaN heterojunction bipolar transistors with a current gain of 20, demonstrated using emitter regrowth technique.

  9. Synthesis of flower-like Ag{sub 2}O/BiOCOOH p-n heterojunction with enhanced visible light photocatalytic activity

    Energy Technology Data Exchange (ETDEWEB)

    Li, Shijie [Innovation & Application Institute, Zhejiang Ocean University, Zhoushan, Zhejiang Province 316022 (China); Zhejiang Provincial Key Laboratory of Health Risk Factors for Seafood, Zhoushan Municipal Center for Disease Control and Prevention, Zhoushan 316021 (China); State Environmental Protection Engineering Center for Pollution Treatment and Control in Textile Industry, College of Environmental Science and Engineering, Donghua University, Shanghai 201620 (China); Xu, Kaibing [State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, Research Center for Analysis and Measurement, Donghua University, Shanghai 201620 (China); Hu, Shiwei, E-mail: hushiweihai@163.com [Innovation & Application Institute, Zhejiang Ocean University, Zhoushan, Zhejiang Province 316022 (China); Jiang, Wei [Innovation & Application Institute, Zhejiang Ocean University, Zhoushan, Zhejiang Province 316022 (China); Zhejiang Provincial Key Laboratory of Health Risk Factors for Seafood, Zhoushan Municipal Center for Disease Control and Prevention, Zhoushan 316021 (China); Zhang, Junlei [Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention (LAP3), Department of Environmental Science and Engineering, Fudan University, Shanghai 200433 (China); Liu, Jianshe [State Environmental Protection Engineering Center for Pollution Treatment and Control in Textile Industry, College of Environmental Science and Engineering, Donghua University, Shanghai 201620 (China); Zhang, Lisha, E-mail: lszhang@dhu.edu.cn [State Environmental Protection Engineering Center for Pollution Treatment and Control in Textile Industry, College of Environmental Science and Engineering, Donghua University, Shanghai 201620 (China)

    2017-03-01

    Highlights: • Ag{sub 2}O/BiOCOOH p-n heterojunctions are prepared by a solvothermal deposition-precipitation method. • They consist of flower-like BiOCOOH microspheres decorated with Ag{sub 2}O nanoparticles. • Heterojunction with the Ag/Bi molar ratio of 0.2/1 showed the highest photocatalytic activity. • The photogenerated holes (h{sup +}) and superoxide radical anions (·O{sub 2}{sup −}) have been found to be the main reactive species. - Abstract: The development of efficient semiconductor heterojunction photocatalysts has drawn much attention. Herein, we have reported a kind of flower-like Ag{sub 2}O/BiOCOOH p-n heterojunction as a novel and efficient visible-light-driven photocatalyst. The Ag{sub 2}O/BiOCOOH heterojunctions have been successfully prepared via a solvothermal precipitation-deposition method. They consist of flower-like BiOCOOH microspheres (diameters: 1–2.5 μm) decorated with Ag{sub 2}O nanoparticles (size: ∼14 nm). In addition, optical characterization reveals that they have broad visible-light photo-absorption. Importantly, under visible-light irradiation (λ > 400 nm), all Ag{sub 2}O/BiOCOOH heterojunctions exhibit enhanced photocatalytic activity than pure BiOCOOH or Ag{sub 2}O for the degradation of rhodamine B (RhB) dye and para-chlorophenol (4-CP). Especially, the Ag{sub 2}O/BiOCOOH heterojunction with the Ag/Bi molar ratio of 0.2/1 shows the highest photocatalytic activity, which is even higher than the activity from the mechanical mixture (8 wt% Ag{sub 2}O + 92 wt% BiOCOOH). This enhanced photocatalytic performance could be predominantly attributed to the efficient separation of photogenerated electron-hole pairs. The photogenerated holes (h{sup +}) and superoxide radical anions (·O{sub 2}{sup −}) have been found to be the main reactive species responsible for the photodegradation of RhB dye in aqueous solution. Therefore, the Ag{sub 2}O/BiOCOOH p-n heterojunction has great potential to be used as a kind of efficient

  10. Solution-Processed Metal-Oxide p-n Charge Generation Junction for High-Performance Inverted Quantum-Dot Light-Emitting Diodes.

    Science.gov (United States)

    Kim, Hyo-Min; Kim, Jeonggi; Cho, Sin-Young; Jang, Jin

    2017-11-08

    We report solution-processed metal-oxide p-n junction, Li-doped CuO (Li:CuO) and Li-doped ZnO (Li:ZnO), as a charge generation junction (CGJ) in quantum-dot light-emitting diode (QLED) at reverse bias. Efficient charge generation is demonstrated in a stack of air-annealed Li:CuO and Li:ZnO layers in QLEDs. Air annealing of Li:ZnO on Li:CuO turns out to be a key process to decrease oxygen vacancy (Vo) and increase the copper (II) oxide (CuO) fraction at the Li:CuO/Li:ZnO interface for efficient charge generation. Green QLEDs incorporating Li:CuO/Li:ZnO CGJ show the maximum current and power efficiencies of 35.4 cd/A and 33.5 lm/W, respectively.

  11. Epitaxial growth of a monolayer WSe2-MoS2 lateral p-n junction with an atomically sharp interface

    Science.gov (United States)

    Li, Ming-Yang; Shi, Yumeng; Cheng, Chia-Chin; Lu, Li-Syuan; Lin, Yung-Chang; Tang, Hao-Lin; Tsai, Meng-Lin; Chu, Chih-Wei; Wei, Kung-Hwa; He-Hau, Jr.; Chang, Wen-Hao; Suenaga, Kazu; Li, Lain-Jong

    2015-07-01

    Two-dimensional transition metal dichalcogenides (TMDCs) such as molybdenum sulfide MoS2 and tungsten sulfide WSe2 have potential applications in electronics because they exhibit high on-off current ratios and distinctive electro-optical properties. Spatially connected TMDC lateral heterojunctions are key components for constructing monolayer p-n rectifying diodes, light-emitting diodes, photovoltaic devices, and bipolar junction transistors. However, such structures are not readily prepared via the layer-stacking techniques, and direct growth favors the thermodynamically preferred TMDC alloys. We report the two-step epitaxial growth of lateral WSe2-MoS2 heterojunction, where the edge of WSe2 induces the epitaxial MoS2 growth despite a large lattice mismatch. The epitaxial growth process offers a controllable method to obtain lateral heterojunction with an atomically sharp interface.

  12. Effect of Plasma, RF, and RIE Treatments on Properties of Double-Sided High Voltage Solar Cells with Vertically Aligned p-n Junctions

    Directory of Open Access Journals (Sweden)

    Mykola O. Semenenko

    2016-01-01

    Full Text Available Si-based solar cells with vertically aligned p-n junctions operating at high voltage were designed and fabricated. The plasma treatments and antireflection coating deposition on the working surfaces of both single- and multijunction cells were made using the special holders. It was shown that additional treatment of solar cells in argon plasma prior to hydrogen plasma treatment and deposition of diamond-like carbon antireflection films led to the improvement of the cell efficiency by up to 60%. Radio frequency waves support plasma generation and improve photoelectric conversion mainly due to reduction of internal stresses at the interfaces. Application of reactive ion etching technique removes the broken layer, reduces elastic strain in the wafer, decreases recombination of charge carriers in the bulk, and provides cell efficiency increase by up to ten times.

  13. Trp17 and Glu20 residues in conserved WMN(D/E)PN motif are essential for Aspergillus ficuum endoinulinase (EC 3.2.1.7) activity.

    Science.gov (United States)

    Park, Seockyu; Han, Yeonsoo; Kim, Heeun; Song, Songyi; Uhm, Tai-Boong; Chae, Keon-Sang

    2003-06-01

    The importance of the WMN(D/E)PN motif, which is well conserved among beta-fructofuranosidases grouped in the glycosylhydrolase family 32, in Aspergillus ficuum endoinulinase was accessed. Each mutant enzyme generated by site-directed mutagenesis of Trp17 in the conserved motif to Gln, Leu, Ser, Pro, Thr, or Met had an activity of less than 1% of the wild type. Another mutant enzyme obtained by mutation of Glu20 in the motif to Ser, Leu, Thr, Gln, Ala, or Val had an enzyme activity of less than 1% of the wild type. Furthermore, the E20D mutant enzyme, in which Glu20 in the conserved motif was replaced with Asp, had 1.1% of the wild type activity. These results clearly indicated that Trp17 and Glu20 are essential for the enzyme activity.

  14. Epitaxial growth of a monolayer WSe2-MoS2 lateral p-n junction with an atomically sharp interface

    KAUST Repository

    Li, Ming Yang

    2015-07-30

    Two-dimensional transition metal dichalcogenides (TMDCs) such as molybdenum sulfide MoS2 and tungsten sulfide WSe2 have potential applications in electronics because they exhibit high on-off current ratios and distinctive electro-optical properties. Spatially connected TMDC lateral heterojunctions are key components for constructing monolayer p-n rectifying diodes, light-emitting diodes, photovoltaic devices, and bipolar junction transistors. However, such structures are not readily prepared via the layer-stacking techniques, and direct growth favors the thermodynamically preferred TMDC alloys. We report the two-step epitaxial growth of lateral WSe2-MoS2 heterojunction, where the edge of WSe2 induces the epitaxial MoS2 growth despite a large lattice mismatch. The epitaxial growth process offers a controllable method to obtain lateral heterojunction with an atomically sharp interface.

  15. NANOELECTRONICS. Epitaxial growth of a monolayer WSe2-MoS2 lateral p-n junction with an atomically sharp interface.

    Science.gov (United States)

    Li, Ming-Yang; Shi, Yumeng; Cheng, Chia-Chin; Lu, Li-Syuan; Lin, Yung-Chang; Tang, Hao-Lin; Tsai, Meng-Lin; Chu, Chih-Wei; Wei, Kung-Hwa; He, Jr-Hau; Chang, Wen-Hao; Suenaga, Kazu; Li, Lain-Jong

    2015-07-31

    Two-dimensional transition metal dichalcogenides (TMDCs) such as molybdenum sulfide MoS2 and tungsten sulfide WSe2 have potential applications in electronics because they exhibit high on-off current ratios and distinctive electro-optical properties. Spatially connected TMDC lateral heterojunctions are key components for constructing monolayer p-n rectifying diodes, light-emitting diodes, photovoltaic devices, and bipolar junction transistors. However, such structures are not readily prepared via the layer-stacking techniques, and direct growth favors the thermodynamically preferred TMDC alloys. We report the two-step epitaxial growth of lateral WSe2-MoS2 heterojunction, where the edge of WSe2 induces the epitaxial MoS2 growth despite a large lattice mismatch. The epitaxial growth process offers a controllable method to obtain lateral heterojunction with an atomically sharp interface. Copyright © 2015, American Association for the Advancement of Science.

  16. Facile fabrication of BiOI decorated NaNbO3 cubes: A p-n junction photocatalyst with improved visible-light activity

    Science.gov (United States)

    Sun, Meng; Yan, Qing; Shao, Yu; Wang, Changqian; Yan, Tao; Ji, Pengge; Du, Bin

    2017-09-01

    To enhance the separation efficiency of photo-generated carriers, a p-n junction photocatalyst BiOI/NaNbO3 has been fabricated by a facile method. The obtained samples were characterized by XRD, SEM, TEM, HRTEM, PL, N2 sorption-desorption and DRS. DRS results showed that the light absorption edges of BiOI/NaNbO3 hybrids were red-shifted with the increase of BiOI content. The SEM and TEM images revealed that the BiOI was widely decorated over the surfaces of NaNbO3 cubes. The formation of p-n heterojunction at their interfaces was proved by the HRTEM image. The visible light-driven photocatalytic activity was evaluated by the degradation of methylene blue (MB) in aqueous solution. Compared with single NaNbO3 and BiOI, the BiOI/NaNbO3 hybrid photocatalysts have exhibited significantly enhanced activities. Meanwhile, the mass ratio of BiOI/NaNbO3 displayed important influence on the MB degradation. The hybrid photocatalyst with BiOI content of 40% performed the optimal activity. This activity enhancement should be attributed to the strong visible light absorption, the high migration and separation efficiency of photo-induced carriers. The photocurrent and PL measurements confirmed that the interfacial charge separation efficiency was greatly improved by coupling BiOI with NaNbO3. Controlled experiments proved that the degradation of pollutants was mainly attributed to the oxidizing ability of the generated holes (h+), ·O2-, and ·OH radicals.

  17. Simulation of MWIR and LWIR photodiodes based on n +-p and p-n junctions formed in HgCdTe heterostructures

    Science.gov (United States)

    Chekanova, Galina V.; Drugova, Albina A.; Kholodnov, Viacheslav; Nikitin, Mikhail S.

    2007-10-01

    Realization of affordable large format high performance photovoltaic (PV) infrared (IR) Hg 1-xCd xTe based focal plane arrays (FPA) covering spectral ranges Mid-Wave (MWIR) from 3 to 5.5 μm and extended Long-Wave (LWIR) from 8 to 14 μm requires comprehensive estimation of photodiodes performance depending on Hg 1-xCd xTe material properties and operating conditions. Advanced Infrared Focal Plane Arrays include Mid-Wave (MWIR) 3-5.5 μm operating at temperatures T op=80-100 K and at higher temperatures (HOT) T op=200-240 K, extended Long-Wave (LWIR) 8-14 μm operating at temperatures T op=80-100 K and multi-color arrays. Perhaps novel FPA will be based on photodiodes (PD) with p-n junction opposite to usually used n +-p junction. PD with optimal p-n junction could have lower dark current value than same size n +-p junction. It is desirable for proper multiplexing of PD arrays to Silicon Read-out Integrated Circuits (ROICs). Comparative analysis of LWIR PD performance at 80 K and 100 K is needed also due to strong tendency to lowering weight and power consumption of perspective megapixel FPA. Objective of the present work was to calculate Hg 1-xCd xTe MWIR and LWIR PV FPA (λp equals to 4.5-4.8 μm at T op=225 K responding 2-3 stages thermal electric cooler temperature and 8.0-9.0 and 10.0-10.5 μm at T op=80-100 K) performance variation with doping level, absorber thickness, surface recombination rate and operating temperature.

  18. Feshbach-Kerman-Koonin model analysis of preequilibrium (p,p') and (p,n) reactions at 12 to 26 MeV

    Science.gov (United States)

    Watanabe, Y.; Aoto, A.; Kashimoto, H.; Chiba, S.; Fukahori, T.; Hasegawa, K.; Mizumoto, M.; Meigo, S.; Sugimoto, M.; Yamanouti, Y.; Koori, N.; Chadwick, M. B.; Hodgson, P. E.

    1995-04-01

    Double-differential proton emission cross sections have been measured for proton-induced reactions on 98Mo and 106Pd at incident energies around 26 MeV. Several sets of (p,p') and (p,n) data for both target nuclei at incident energies from 12 to 26 MeV are analyzed in terms of the multistep-direct (MSD) and multistep-compound (MSC) reaction models of Feshbach, Kerman, and Koonin (FKK). The strength V0 of the effective N-N interaction is extracted from a fit of the calculated MSD spectrum to the experimental data using the subtraction method of isolating and analyzing the MSD component alone. A similar analysis is also applied to (p,p') and (n,n') data for 93Nb in the same energy region. The experimental nucleon emission spectra at 26 MeV are reproduced well by the calculation that includes preequilibrium MSD and MSC emission, direct collective excitation to low-lying discrete levels, and Hauser-Feshbach equilibrium emission in a quantum-mechanical way. The systematic dependence of V0 on the incident energy and the nature of projectiles and ejectiles is investigated. In addition, the sensitivities to input parameters used in the MSD calculation (the optical model potential parameters, the pairing correction, and the nonlocality correction) are examined in order to see their effect on the determination of V0. The possibility of gradual absorption of reaction flux from the P to the Q chain is also discussed through analyses of preequilibrium (p,p') and (p,n) spectra using a phenomenological phase space approach.

  19. Controlled carrier screening in p-n NiO/GaN piezoelectric generators by an Al2O3 insertion layer

    Science.gov (United States)

    Johar, Muhammad Ali; Jeong, Dae Kyung; Afifi Hassan, Mostafa; Kang, Jin-Ho; Ha, Jun-Seok; Key Lee, June; Ryu, Sang-Wan

    2017-12-01

    The performance of a piezoelectric generator (PG) depends significantly on the internal screening process inside the device. As piezoelectric charges appear on both ends of the piezoelectric crystal, internal screening starts to decrease the piezoelectric bias. Therefore, the piezoelectric energy generated by external stress is not fully utilized by external circuit, which is the most challenging aspect of high-efficiency PGs. In this work, the internal screening effect of a NiO/GaN p-n PG was analyzed and controlled with an Al2O3 insertion layer. Internal screening in the p-n diode PG was categorized into free-carrier screening in neutral regions and junction screening due to charge drift across the junction. It was observed that junction screening could be significantly suppressed by inserting an Al2O3 layer and that effect was dominant in a leaky diode PG. With this implementation, the piezoelectric bias of the NiO/GaN PG was improved by a factor of ~100 for high-leakage diodes and a factor of ~1.6 for low-leakage diodes. Consequently, NiO/Al2O3/GaN PGs under a stress of 5 MPa provided a piezoelectric bias of 12.1 V and a current density of 2.25 µA cm‑2. The incorporation of a highly resistive Al2O3 layer between p-NiO and n-GaN layers in NiO/GaN heterojunctions provides an efficient means of improving the piezoelectric performance by controlling the internal screening of the piezoelectric field.

  20. Integrated Advanced Microwave Sounding Unit-A (AMSU-A). Engineering Test Report: METSAT A1 Signal Processor (P/N: 1331670-2, S/N: F04)

    Science.gov (United States)

    Lund, D.

    1998-01-01

    This report presents a description of the tests performed, and the test data, for the A1 METSAT Signal Processor Assembly PN: 1331679-2, S/N F04. The assembly was tested in accordance with AE-26754, "METSAT Signal Processor Scan Drive Test and Integration Procedure." The objective is to demonstrate functionality of the signal processor prior to instrument integration.

  1. Regio- and stereo-selective polymerization of 1,3-butadiene catalyzed by phosphorus–nitrogen PN3-pincer cobalt(ii) complexes

    KAUST Repository

    Gong, Dirong

    2016-11-11

    A new family of cobalt complexes (CoCl2-H, CoCl2-Me, CoCl2-iPr, CoBr2-H, CoBr2-Me, CoBr2-iPr, CoI2-H, CoI2-Me, and CoI2-iPr) supported by a PN3 ligand (6-(N,N′-di-t-butylphosphino)-2-pyrazol-yl-aminopyridine) have been prepared and fully characterized by FT-IR, elemental analysis, and X-ray analysis. The X-ray analysis reveals a trigonal bipyramidal conformation in the solid state for all representative complexes, CoCl2-H, CoBr2-H, CoBr2-iPr and CoI2-Me. The cobalt center is chelated by the PN3 ligand through the pyridinyl nitrogen, the pyrazol nitrogen and the phosphorus donor, with a long Co-P bond distance indicating a labile character. On activation with AlEt2Cl, Al2Et3Cl3, MAO, [Ph3C]+[B(C6F5)4]-/AliBu3 or AliBu3, cis-1,4 selective butadiene polymerization was achieved with up to 98.6% selectivity. The polymerization results show that the cis-1,4 selectivity is influenced by the steric hindrance, increasing with the bulkiness of the substituent groups (CoX2-iPr > CoX2-Me > CoX2-H) at the 3,5-positions of the pyrazole moiety, together with a slight decrease in activity. The activity changes in the order CoCl2L ≈ CoBr2L > CoI2L (for the same ligand L) when MAO is used as the activator, while the high level of cis-1,4 selectivity is maintained. It is possible to switch the selectivity from cis-1,4 to syndiotactic-1,2 by adding PPh3 © The Royal Society of Chemistry.

  2. One-sided rectifying p-n junction diodes fabricated from n-CdS and p-ZnTe:Te semiconductors

    Science.gov (United States)

    Olusola, O. I.; Salim, H. I.; Dharmadasa, I. M.

    2016-09-01

    The fabrication of a one-sided p-n hetero-junction (HJ) diodes have been successfully carried out using both p-type ZnTe and n-CdS semiconductors. Chemical bath deposition (CBD) and electrodeposition (ED) techniques have been used in the deposition of n-CdS and p-ZnTe layers respectively. Before the fabrication of the one-sided p-n HJ diodes, the electrical properties of glass/FTO/p-ZnTe/Al and glass/FTO/n-CdS/Au rectifying structures were separately studied using capacitance-voltage (C-V) technique so as to determine the doping density of each of the thin films. The results from C-V analyses showed that p-ZnTe is moderately doped with an acceptor density of 3.55 × 1015 cm-3 while n-CdS is heavily doped with a donor density of 9.00 × 1019 cm-3. The heavy doping of n-CdS and moderate doping of p-ZnTe will make the interface between n-CdS and p-ZnTe thin films a one-sided n+p diode. Therefore, to fabricate the CdS/ZnTe hetero-structure, it was ensured that approximately same thickness of CdS and ZnTe thin films being used in the initial experiment to study the electrical properties of glass/FTO/n-CdS/Au and glass/FTO/p-ZnTe/Al were also used in the development of the one-sided n+p junction diodes to obtain more accurate results. The electronic properties of the device structure were studied using both current-voltage (I-V) and C-V measurement techniques. The I-V results show that the one-sided n+p HJ diodes possess good rectifying quality with a series resistance (R s) of ˜35 Ω and rectification factors exceeding 102.7 under dark condition. The results of the C-V analyses showed that the acceptor density of the one-sided n+p HJ diode is of the order of 1015 cm-3 while the donor density is of the order of 1018 cm-3. The results obtained from this analysis still showed the moderate doping of p-ZnTe and the degenerate nature of n-CdS.

  3. A new method for polychromatic X-ray μLaue diffraction on a Cu pillar using an energy-dispersive pn-junction charge-coupled device.

    Science.gov (United States)

    Abboud, A; Kirchlechner, C; Send, S; Micha, J S; Ulrich, O; Pashniak, N; Strüder, L; Keckes, J; Pietsch, U

    2014-11-01

    μLaue diffraction with a polychromatic X-ray beam can be used to measure strain fields and crystal orientations of micro crystals. The hydrostatic strain tensor can be obtained once the energy profile of the reflections is measured. However, this remains a challenge both on the time scale and reproducibility of the beam position on the sample. In this review, we present a new approach to obtain the spatial and energy profiles of Laue spots by using a pn-junction charge-coupled device, an energy-dispersive area detector providing 3D resolution of incident X-rays. The morphology and energetic structure of various Bragg peaks from a single crystalline Cu micro-cantilever used as a test system were simultaneously acquired. The method facilitates the determination of the Laue spots' energy spectra without filtering the white X-ray beam. The synchrotron experiment was performed at the BM32 beamline of ESRF using polychromatic X-rays in the energy range between 5 and 25 keV and a beam size of 0.5 μm × 0.5 μm. The feasibility test on the well known system demonstrates the capabilities of the approach and introduces the "3D detector method" as a promising tool for material investigations to separate bending and strain for technical materials.

  4. Electron-beam-induced current measurements with applied bias provide insight to locally resolved acceptor concentrations at p-n junctions

    Directory of Open Access Journals (Sweden)

    D. Abou-Ras

    2015-07-01

    Full Text Available Electron-beam-induced current (EBIC measurements have been employed for the investigation of the local electrical properties existing at various types of electrical junctions during the past decades. In the standard configuration, the device under investigation is analyzed under short-circuit conditions. Further insight into the function of the electrical junction can be obtained when applying a bias voltage. The present work gives insight into how EBIC measurements at applied bias can be conducted at the submicrometer level, at the example of CuInSe2 solar cells. From the EBIC profiles acquired across ZnO/CdS/CuInSe2/Mo stacks exhibiting p-n junctions with different net doping densities in the CuInSe2 layers, values for the width of the space-charge region, w, were extracted. For all net doping densities, these values decreased with increasing applied voltage. Assuming a linear relationship between w2 and the applied voltage, the resulting net doping densities agreed well with the ones obtained by means of capacitance-voltage measurements.

  5. Extracellular expression of glucose inhibition-resistant Cellulomonas flavigena PN-120 β-glucosidase by a diploid strain of Saccharomyces cerevisiae.

    Science.gov (United States)

    Mendoza-Aguayo, David J; Poggi-Varaldo, Héctor M; García-Mena, Jaime; Ramos-Valdivia, Ana C; Salgado, Luis M; de la Torre-Martínez, Mayra; Ponce-Noyola, Teresa

    2014-01-01

    The catalytic fraction of the Cellulomonas flavigena PN-120 oligomeric β-glucosidase (BGLA) was expressed both intra- and extracellularly in a recombinant diploid of Saccharomyces cerevisiae, under limited nutrient conditions. The recombinant enzyme (BGLA¹⁵) expressed in the supernatant of a rich medium showed 582 IU/L and 99.4 IU/g dry cell, with p-nitrophenyl-β-D-glucopyranoside as substrate. BGLA¹⁵ displayed activity against cello-oligosaccharides with 2-5 glucose monomers, demonstrating that the protein is not specific for cellobiose and that the oligomeric structure is not essential for β-D-1,4-bond hydrolysis. Native β-glucosidase is inhibited almost completely at 160 mM glucose, thus limiting cellobiose hydrolysis. At 200 mM glucose concentration, BGLA¹⁵ retained more than 50 % of its maximal activity, and even at 500 mM glucose concentration, more than 30 % of its activity was preserved. Due to these characteristics of BGLA¹⁵ activity, recombinant S. cerevisiae is able to utilize cellulosic materials (cello-oligosaccharides) to produce bioethanol.

  6. A new method for polychromatic X-ray μLaue diffraction on a Cu pillar using an energy-dispersive pn-junction charge-coupled device

    Science.gov (United States)

    Abboud, A.; Kirchlechner, C.; Send, S.; Micha, J. S.; Ulrich, O.; Pashniak, N.; Strüder, L.; Keckes, J.; Pietsch, U.

    2014-11-01

    μLaue diffraction with a polychromatic X-ray beam can be used to measure strain fields and crystal orientations of micro crystals. The hydrostatic strain tensor can be obtained once the energy profile of the reflections is measured. However, this remains a challenge both on the time scale and reproducibility of the beam position on the sample. In this review, we present a new approach to obtain the spatial and energy profiles of Laue spots by using a pn-junction charge-coupled device, an energy-dispersive area detector providing 3D resolution of incident X-rays. The morphology and energetic structure of various Bragg peaks from a single crystalline Cu micro-cantilever used as a test system were simultaneously acquired. The method facilitates the determination of the Laue spots' energy spectra without filtering the white X-ray beam. The synchrotron experiment was performed at the BM32 beamline of ESRF using polychromatic X-rays in the energy range between 5 and 25 keV and a beam size of 0.5 μm × 0.5 μm. The feasibility test on the well known system demonstrates the capabilities of the approach and introduces the "3D detector method" as a promising tool for material investigations to separate bending and strain for technical materials.

  7. Structure near $K^-$+$p$+$p$ threshold in the in-flight $^3$He$(K^-,\\Lambda p)n$ reaction

    CERN Document Server

    :,; Ajimura, S; Bazzi, M; Beer, G; Bhang, H; Bragadireanu, M; Buehler, P; Busso, L; Cargnelli, M; Choi, S; Curceanu, C; Enomoto, S; Faso, D; Fujioka, H; Fujiwara, Y; Fukuda, T; Guaraldo, C; Hashimoto, T; Hayano, R S; Hiraiwa, T; Iio, M; Iliescu, M; Inoue, K; Ishiguro, Y; Ishikawa, T; Ishimoto, S; Ishiwatari, T; Itahashi, K; Iwai, M; Iwasaki, M; Kato, Y; Kawasaki, S; Kienle, P; Kou, H; Ma, Y; Marton, J; Matsuda, Y; Mizoi, Y; Morra, O; Nagae, T; Noumi, H; Ohnishi, H; Okada, S; Outa, H; Piscicchia, K; Vidal, A Romero; Sakaguchi, A; Sakuma, F; Sato, M; Scordo, A; Sekimoto, M; Shi, H; Sirghi, D; Sirghi, F; Suzuki, K; Suzuki, S; Suzuki, T; Tanida, K; Tatsuno, H; Tokuda, M; Tomono, D; Toyoda, A; Tsukada, K; Doce, O Vazquez; Widmann, E; Wuenschek, B K; Yamaga, T; Yamazaki, T; Yim, H; Zhang, Q; Zmeskal, J

    2016-01-01

    To search for an S= -1 di-baryonic state which decays to $\\Lambda p$, the $ {\\rm{}^3He}(K^-,\\Lambda p)n_{missing}$ reaction was studied at 1.0 GeV/$c$. Unobserved neutrons were kinematically identified from the missing mass $M_X$ of the $ {\\rm{}^3He}(K^-,\\Lambda p)X$ reaction in order to have a large acceptance for the $\\Lambda pn$ final state. The observed $\\Lambda p n$ events, distributed widely over the kinematically allowed region of the Dalitz plot, establish that the major component comes from a three nucleon absorption process. A concentration of events at a specific neutron kinetic energy was observed in a region of low momentum transfer to the $\\Lambda p$. To account for the observed peak structure, the simplest S-wave pole was assumed to exist in the reaction channel, having Breit-Wigner form in energy and with a Gaussian form-factor. A minimum $\\chi^2$ method was applied to deduce its mass $M_X\\ =$ 2355 $ ^{+ 6}_{ - 8}$ (stat.) $ \\pm 12$ (syst.) MeV/c$^2$, and decay-width $\\Gamma_X\\ = $ 110 $ ^{+ 1...

  8. Enhanced sensitivity and stability of room-temperature NH₃ sensors using core-shell CeO₂ nanoparticles@cross-linked PANI with p-n heterojunctions.

    Science.gov (United States)

    Wang, Lingling; Huang, Hui; Xiao, Songhua; Cai, Daoping; Liu, Yuan; Liu, Bin; Wang, Dandan; Wang, Chenxia; Li, Han; Wang, Yanrong; Li, Qiuhong; Wang, Taihong

    2014-08-27

    We report a room-temperature NH3 gas sensor with high response and great long-term stability, including CeO2 NPs conformally coated by cross-linked PANI hydrogel. Such core-shell nanocomposites were prepared by in situ polymerization with different weight ratios of CeO2 NPs and aniline. At room temperature, the nanohybrids showed enhanced response (6.5 to 50 ppm of NH3), which could be attributed to p-n junctions formed by the intimate contact between these two materials. Moreover, the stability was discussed in terms of phytic acid working as a gelator, which helped the PANI sheath accommodate itself and enhance the mechanical strength and chemical stability of the sensors by avoiding "swelling effect" in high relative humidity. The sensors maintained its sensing characteristic (response of ca. 6.5 to 50 ppm of NH3) in 15 days. Herein, the obtained results could help to accelerate the development of ammonia gas sensor.

  9. The Broad Iron K-alpha line of Cygnus X-1 as Seen by XMM-Newton in the EPIC-pn Modified Timing Mode

    Science.gov (United States)

    Duro, Refiz; Dauser, Thomas; Wilms, Jorn; Pottschmidt, Katja; Nowak, Michael A.; Fritz, Sonja; Kendziorra, Eckhard; Kirsch, Marcus G. F.; Reynolds, Christopher S.; Staubert, Rudiger

    2011-01-01

    We present the analysis of the broadened, flourescent iron K(alpha) line in simultaneous XMM-Newton and RXTE data from the black hole Cygnus X-I. The XMM-Newton data were taken in a modified version of the Timing Mode of the EPIC-pn camera. In this mode the lower energy threshold of the instrument is increased to 2.8 keV to avoid telemetry drop outs due to the brightness of the source, while at the same time preserving the signal to noise ratio in the Fe K(alpha) band. We find that the best-fit spectrum consists of the sum of an exponentially cut-off power-law and relativistically smeared, ionized reflection. The shape of the broadened Fe K(alpha) feature is due to strong Compton broadening combined with relativistic broadening. Assuming a standard, thin accretion disk, the black hole is close to maximally rotating. Key words. X-rays: binaries - black hole physics - gravitation

  10. [The evaluation of bacteria penetration by medical textiles for multiple use and disposable multilayer surgical drapes, according to the PN-EN ISO 22610 standard].

    Science.gov (United States)

    Zareba, Tomasz; Zawistowska, Anna; Kruszewska, Hanna; Mrówka, Agnieszka; Tyski, Stefan

    2012-01-01

    Cotton as well as synthetic textile medical products are widely used as barrier materials and individual protection against displacement of biological infectious factors. The required level of protection of these products for multiple use and disposable multilayer laminates against the penetration of microbes depends on the risk connected with type of surgical procedure defined in normative documents. METHODS. Cotton and syntetic medical textiles for multiple use, 30-times subjected to processes simulating conditions of the use as well as disposable multilayer surgical drapes were tested. Resistance to microbial wet penetration was conducted according to the PN-EN ISO 22610: 2007 standard. The barrier of cotton fabrics was reduced after first washing and then systematically grew after each often cycles to the value close to the value at the beginning. From the twentieth cycle of simulated conditions of the use, barrier index was reduced. The barrier of the synthetic textile stayed on the average level, while multilayer disposable products ensured the full impermeability for the bacteria. Natural cotton textiles for multiple use could be apply on operative blocks in limited range because of the changes of the cotton structure caused by repeated laundering process and sterilization. Synthetic materials also have limited application, although are more resistant to cleaning and sterilization processes. Disposable synthetic laminates with many layers use guarantee impermeability for bacteria and may be applied in operative blocks without restrictions.

  11. High reliable and stable organic field-effect transistor nonvolatile memory with a poly(4-vinyl phenol) charge trapping layer based on a pn-heterojunction active layer

    Energy Technology Data Exchange (ETDEWEB)

    Xiang, Lanyi; Ying, Jun; Han, Jinhua; Zhang, Letian, E-mail: zlt@jlu.edu.cn, E-mail: wwei99@jlu.edu.cn; Wang, Wei, E-mail: zlt@jlu.edu.cn, E-mail: wwei99@jlu.edu.cn [State Key Laboratory on Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, 2699 Qianjin Street, Changchun 130012 (China)

    2016-04-25

    In this letter, we demonstrate a high reliable and stable organic field-effect transistor (OFET) based nonvolatile memory (NVM) with a polymer poly(4-vinyl phenol) (PVP) as the charge trapping layer. In the unipolar OFETs, the inreversible shifts of the turn-on voltage (V{sub on}) and severe degradation of the memory window (ΔV{sub on}) at programming (P) and erasing (E) voltages, respectively, block their application in NVMs. The obstacle is overcome by using a pn-heterojunction as the active layer in the OFET memory, which supplied a holes and electrons accumulating channel at the supplied P and E voltages, respectively. Both holes and electrons transferring from the channels to PVP layer and overwriting the trapped charges with an opposite polarity result in the reliable bidirectional shifts of V{sub on} at P and E voltages, respectively. The heterojunction OFET exhibits excellent nonvolatile memory characteristics, with a large ΔV{sub on} of 8.5 V, desired reading (R) voltage at 0 V, reliable P/R/E/R dynamic endurance over 100 cycles and a long retention time over 10 years.

  12. Embedding Metal in the Interface of a p-n Heterojunction with a Stack Design for Superior Z-Scheme Photocatalytic Hydrogen Evolution.

    Science.gov (United States)

    Yin, Wenjie; Bai, Lijie; Zhu, Yuzhen; Zhong, Shuxian; Zhao, Leihong; Li, Zhengquan; Bai, Song

    2016-09-07

    The construction of a p-n heterojunction is an efficient strategy to resolve the limited light absorption and serious charge-carrier recombination in semiconductors and enhance the photocatalytic activity. However, the promotion effect is greatly limited by poor interfacial charge transfer efficiency as well as reduced redox ability of charge carriers. In this work, we demonstrate that the embedding of metal Pd into the interface between n-type C3N4 and p-type Cu2O can further enhance the interfacial charge transfer and increase the redox ability of charge carriers through the design of the C3N4-Pd-Cu2O stack nanostructure. The embedded Pd nanocubes in the stack structure not only trap the charge carriers from the semiconductors in promoting the electron-hole separation but also act as a Z-scheme "bridge" in keeping the strong reduction/oxidation ability of the electrons/holes for surface reactions. Furthermore, Pd nanocubes also increase the bonding strength between the two semiconductors. Enabled by this unique design, the hydrogen evolution achieved is dramatically higher than that of its counterpart C3N4-Cu2O structure without Pd embedding. The apparent quantum efficiency (AQE) is 0.9% at 420 nm for the designed C3N4-Pd-Cu2O. This work highlights the rational interfacial design of heterojunctions for enhanced photocatalytic performance.

  13. Schottky-barrier heights of single-crystal NiSi2 on Si(111): The effect of a surface p-n junction

    Science.gov (United States)

    Tung, R. T.; Ng, K. K.; Gibson, J. M.; Levi, A. F. J.

    1986-05-01

    Current-voltage, capacitance-voltage, and activation-energy measurements obtained for epitaxial nickel silicides grown on Si(111) have exposed the importance of the temperature used to flash-evaporate oxide off the surface prior to metal deposition. Near-ideal behavior is found for Schottky barriers grown on substrates cleaned at ~820 °C in ultrahigh vacuum. The Fermi-level positions at the interfaces of single-crystal type-A and type-B NiSi2 are shown to differ by greater than 100 meV. Transmission electron microscopy demonstrated the epitaxial perfection of these silicide layers. At a cleaning temperature of 1050 °C, the apparent Schottky-barrier heights increased substantially for substrates with a doping concentration of ND less than approximately 1015 cm-3. This increase is due to the conversion of the n-type semiconductor surface region to p type during the 1050 °C anneal. The presence of this p-n junction results in a high apparent Schottky-barrier height (>~0.75 eV) which no longer bears an immediate relationship to the interface Fermi-level position. Recent discrepancies reported by different groups concerning the barrier heights of NiSi2 on Si(111) are attributed to this effect.

  14. Coproduction of protease and mannanase from Bacillus nealsonii PN-11 in solid state fermentation and their combined application as detergent additives.

    Science.gov (United States)

    David, Aditi; Singh Chauhan, Prakram; Kumar, Aditya; Angural, Steffy; Kumar, Deepak; Puri, Neena; Gupta, Naveen

    2018-03-01

    Bacillus nealsonii PN-11 produces thermo-alkalistable mannanase and protease active in wide temperature and pH range. Optimization of coproduction of protease and mannanase from this strain and application of cocktail of these enzymes as detergent additives were studied. On optimization mannanase yield of 834Ug -1 (11.12 fold increase) and protease yield of 70Ug -1 (4.7 fold increase) could be obtained in a single fermentation. Purification and characterization of mannanase have been done earlier and protease was done during this study and has a molecular mass of 48kDa. pH and temperature optima for protease were 10.0 and 65°C respectively. It was completely stable at 60°C for 3h and retained >80% of activity at pH 11.0 for 1h. Both the enzymes were compatible with detergents individually and in a combination. The wash performance of the detergent on different type of stains improved when protease or mannanase were used individually. However destaining was more efficient when a combination of mannanase and protease was used. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. The molecular structure of gaseous dichloro(dimethylamino)phosphane, Cl 2PN(CH 3) 2, by electron diffraction and density functional theory calculations

    Science.gov (United States)

    Baskakova, Polina E.; Belyakov, Alexander V.; Haaland, Arne; Volden, Hans Vidar

    2001-06-01

    The molecular structure of the title compound has been investigated by gas electron diffraction and DFT calculations at the B3PW91/6-311+G∗ level. The equilibrium conformation is characterised by an approximately orthogonal orientation of the electron lone pars on the N and P atoms; the dihedral angle lpNPlp is 78(3)° (lp=lone pair). The configuration of the N atom is quasi-planar; the sum of the three valence angles being 356(2)°. It is suggested that the orthogonal conformation is stabilized by an anomeric effect, i.e. through delocalization of the electron lone pair on N into an antibonding σ∗(P-Cl) orbital. The P-CI bond which is anti the N lone pair is P-Cl†=2.099(3) Å, the one which is gauche P-Cl=2.056(3) Å, the valence angle NPCl†=1053(11)°, NPCl=101.8(11)°. The P-N bond distance is 1.663(4) Å.

  16. β- transitions of 16 7N9 → 16 8O8 with optimized SDI residual interaction using pnTDA and TDA approximations

    Science.gov (United States)

    Pahlavani, M. R.; Firoozi, B.

    2015-11-01

    Within a developed particle-hole approach, a systematic study of the β- transition from the ground state of the 16N nucleus to the ground and some exited states of the 16O nucleus has been carried out. The energy spectrum and the wave functions of pure configuration of the 16N and 16O nuclei are numerically obtained using the mean-field shell model with respect to the Woods-Saxon nuclear potential accompanying spin-orbit and Coulomb interaction. Considering SDI residual interaction, mixed configuration of ground and excited pnTDA and TDA states are extracted for the aforementioned nucleus. These energy spectra and corresponding eigenstates are highly correspondent to the experimental energy spectrum and eigenstates after adjusting the residual potential parameters using the Nelder-Mead (NM) algorithm. In this approach, the endpoint energy, log ft and the partial half-lives of some possible transitions are calculated. The obtained results using the optimized SDI approach are reasonably close to the available experimental data.

  17. Preparation of p-type semiconductor perovskite La1-xSrxCoO3 films and their p-n heterostructure devices

    Science.gov (United States)

    Takashima, Hiroshi; Kikuchi, Naoto; Kawanaka, Hirofumi; Tonooka, Kazuhiko; Aiura, Yoshihiro

    2017-11-01

    Semiconductor La0.67Sr0.33CoO3 thin films has been investigated as function of oxygen atmosphere during film growth in pulsed laser deposition. While amount of oxygen greatly depends on an oxygen atmosphere during film growth, in condition of oxygen atmosphere from 4 Pa to 100 Pa, the carrier in La0.67Sr0.33CoO3 thin films were found to be positive, exhibiting p-type conduction. Furthermore, we prepared (p)-La0.67Sr0.33CoO3/(i)-CeO2/(n)-InGaZnOx heterostructure devices and investigated electrical properties. These results showed rectifying behavior was clearly observed in heterostructure at room temperature. The sharp increase of current with voltage, when voltage exceeds diffusion potential, indicates the conductive resistance was small. p-type semiconductor La0.67Sr0.33CoO3 thin films and their p-n heterostructure devices with rectifying behavior may aid in the development of various semiconductor devices such as three terminal transistors, light emitted diode (LED) and solar cell.

  18. Synthesis and characterization of heterobimetallic complexes of the type [Cu(pn2][MCl4] where M = Co(II, Ni(II, Cu(II, Zn(II, Cd(II, and Hg(II

    Directory of Open Access Journals (Sweden)

    Seema Yadav

    2016-11-01

    Full Text Available A series of new bimetallic transition metal complexes of the type [Cu(pn2] [MCl4] have been synthesized (where M = Co(II, Ni(II, Cu(II, Zn(II, Cd(II and Hg(II, pn = 1,3-diaminopropane and characterized by elemental analysis, molar conductance, TGA, IR and electronic spectra. All the compounds are 1:1 electrolyte in DMF. The Cu(II ion is square-planar while metal ions in the anionic moiety acquire their usual tetrahedral arrangement. On the basis of these studies it is concluded that anionic moiety is electrically stabilized by its cationic counterpart.

  19. Models of the iron-only hydrogenase: a comparison of chelate and bridge isomers of Fe2(CO)4{Ph2PN(R)PPh2}(μ-pdt) as proton-reduction catalysts.

    Science.gov (United States)

    Ghosh, Shishir; Hogarth, Graeme; Hollingsworth, Nathan; Holt, Katherine B; Richards, Idris; Richmond, Michael G; Sanchez, Ben E; Unwin, David

    2013-05-21

    Reactions of Fe2(CO)6(μ-pdt) (pdt = SCH2CH2CH2S) with aminodiphosphines Ph2PN(R)PPh2 (R = allyl, (i)Pr, (i)Bu, p-tolyl, H) have been carried out under different conditions. At room temperature in MeCN with added Me3NO·2H2O, dibasal chelate complexes Fe2(CO)4{κ(2)-Ph2PN(R)PPh2}(μ-pdt) are formed, while in refluxing toluene bridge isomers Fe2(CO)4{μ-Ph2PN(R)PPh2}(μ-pdt) are the major products. Separate studies have shown that chelate complexes convert to the bridge isomers at higher temperatures. Two pairs of bridge and chelate isomers (R = allyl, (i)Pr) have been crystallographically characterised together with Fe2(CO)4{μ-Ph2PN(H)PPh2}(μ-pdt). Chelate complexes adopt the dibasal diphosphine arrangement in the solid state and exhibit very small P-Fe-P bite-angles, while the bridge complexes adopt the expected cisoid dibasal geometry. Density functional calculations have been carried out on the chelate and bridge isomers of the model compound Fe2(CO)4{Ph2PN(Me)PPh2}(μ-pdt) and reveal that the bridge isomer is thermodynamically favourable relative to the chelate isomers that are isoenergetic. The HOMO in each of the three isomers exhibits significant metal-metal bonding character, supporting a site-specific protonation of the iron-iron bond upon treatment with acid. Addition of HBF4·Et2O to the Fe2(CO)4{κ(2)-Ph2PN(allyl)PPh2}(μ-pdt) results in the clean formation of the corresponding dibasal hydride complex [Fe2(CO)4{κ(2)-Ph2PN(allyl)PPh2}(μ-H)(μ-pdt)][BF4], with spectroscopic measurements revealing the intermediate formation of a basal-apical isomer. A crystallographic study reveals that there are only very small metric changes upon protonation. In contrast, the bridge isomers react more slowly to form unstable species that cannot be isolated. Electrochemical and electrocatalysis studies have been carried out on the isomers of Fe2(CO)4{Ph2PN(allyl)PPh2}(μ-pdt). Electron accession is predicted to occur at an orbital that is anti-bonding with respect to

  20. Study of short-range correlation in nuclei via measurement of the 4He(,ee'pp) and 4He(e,e'pn) reaction

    Energy Technology Data Exchange (ETDEWEB)

    Korover, Igor [Tel Aviv Univ., Ramat Aviv (Israel)

    2015-04-01

    This thesis reports on a simultaneous measurement of the 4He(e,e'p), 4He(e,e'pp), and 4He(e,e'pn) reactions at Q2 = 2 (GeV/c)2 and xB > 1 for an (e,e'p) missing momentum range of 400 to 830 MeV/c.

  1. Deuteron ground state properties and low energy P-N scattering [sup 1]S[sub 0] and [sup 3]S[sub 1]-[sup 3]D[sub 1] channels

    Energy Technology Data Exchange (ETDEWEB)

    Gridnev, K.A.; Soubbotin, V.B.; Stepukov, V.B.; Fadeev, S.N. (St. Petersburg Inst. of Nuclear Physics, Gatchina (Russian Federation)); Vinas, X. (Departament d' Estructura i Constituents de la Materia, Facultat de Fisica, Universitat de Barcelona, Diagonal 647, E-08028 Barcelona (Spain))

    1999-09-01

    Deuteron properties and P-N elastic scattering in [sup 1]S[sub 0] and [sup 3]S[sub 1] - [sup 3]D[sub 1] channels are described within the framework of a model containing non-local interactions that take into account quark exchange processes. Comparisons with other theoretical results are also made. (orig.) With 6 figs., 1 tab., 44 refs.

  2. Deuteron ground state properties and low energy P-N scattering {sup 1}S{sub 0} and {sup 3}S{sub 1}-{sup 3}D{sub 1} channels

    Energy Technology Data Exchange (ETDEWEB)

    Gridnev, K.A.; Soubbotin, V.B.; Stepukov, V.B.; Fadeev, S.N. [St. Petersburg Inst. of Nuclear Physics, Gatchina (Russian Federation); Vinas, X. [Departament d`Estructura i Constituents de la Materia, Facultat de Fisica, Universitat de Barcelona, Diagonal 647, E-08028 Barcelona (Spain)

    1999-09-01

    Deuteron properties and P-N elastic scattering in {sup 1}S{sub 0} and {sup 3}S{sub 1} - {sup 3}D{sub 1} channels are described within the framework of a model containing non-local interactions that take into account quark exchange processes. Comparisons with other theoretical results are also made. (orig.) With 6 figs., 1 tab., 44 refs.

  3. Prognostic value of HPV-mRNA in sentinel lymph nodes of cervical cancer patients with pN0-status.

    Science.gov (United States)

    Dürst, Matthias; Hoyer, Heike; Altgassen, Christoph; Greinke, Christiane; Häfner, Norman; Fishta, Alba; Gajda, Mieczyslaw; Mahnert, Ute; Hillemanns, Peter; Dimpfl, Thomas; Lenhard, Miriam; Petry, K Ulrich; Runnebaum, Ingo B; Schneider, Achim

    2015-09-08

    Up to 15% of patients with cervical cancer and pN0-status develop recurrent-disease. This may be due to occult metastatic spread of tumor cells. We evaluated the use of human-papillomavirus-(HPV)-mRNA as a molecular marker for disseminated tumor cells to predict the risk of recurrence. For this prospective, multi-center prognostic study, 189 patients free of lymphnode metastases by conventional histopathology could be analyzed. All patients underwent complete lymphadenectomy. Of each sentinel node (SLN) a biopsy was taken for the detection of HPV-E6-E7-mRNA. Median follow-up time after surgery was 8.1 years. HPV-mRNA could be detected in SLN of 52 patients (27.5%). Recurrence was observed in 22 patients. Recurrence-free-survival was significantly longer for patients with HPV-negative SLN (log rank p = 0.002). By Cox regression analysis the hazard ratio (95%CI) for disease-recurrence was 3.8 (1.5 - 9.3, p = 0.004) for HPV-mRNA-positive compared to HPV-mRNA-negative patients. After adjustment for tumor size as the most influential covariate the HR was still 2.8 (1.1 - 7.0, p = 0.030). In patients with cervical cancer and tumor-free lymph nodes by conventional histopathology HPV-mRNA-positive SLN were of prognostic value independent of tumor size. Particularly, patients with tumors larger than 20mm diameter could possibly benefit from further risk stratification using HPV-mRNA as a molecular marker.

  4. Defining Usability of PN Services

    DEFF Research Database (Denmark)

    Nicolajsen, Hanne Westh; Ahola, Titta; Fleury, Alexandre

    status of the pilot services. The evaluation will be conducted on two pilot services, that are being implemented - the Lifestyle companion and the Icebreaker. The plan of the evaluation is to carry out combinations of different types of user evaluation methods. These are user panel workshops, situated...... user testing (e.g. test scenarios), and interviews/post workshops and questionnaires....

  5. Characterization of Polar, Semi-Polar, and Non-Polar p-n Homo and Hetero-junctions grown by Ammonia Molecular Beam Epitaxy

    Science.gov (United States)

    Hurni, Christophe Antoine

    Widespread interest in the group III-Nitrides began with the achievement of p-type conductivity in the early 1990s in Mg-doped GaN films grown by metal organic chemical vapor deposition (MOCVD) by Nakamura et al. Indeed, MOCVD-grown Mg-doped GaN is insulating as-grown, because of the formation of neutral Mg-H complexes. Nakamura et al. showed that a rapid thermal anneal removes the hydrogen and enables p-conductivity. Shortly after this discovery, the first LEDs and lasers were demonstrated by Nakamura et al. The necessary annealing step is problematic for devices which need a buried p-layer, such as hetero-junction bipolar transistors. Ammonia molecular beam epitaxy (NH3-MBE) has a great potential for growing vertical III-Nitrides-based devices, thank to its N-rich growth conditions and all the usual advantages of MBE, which include a low-impurity growth environment, in situ monitoring techniques as well as the ability to grow sharp interfaces. We first investigated the growth of p-GaN by NH3-MBE. We found that the hole concentration strongly depends on the growth temperature. Thanks to comprehensive Hall and transfer length measurements, we found evidences for a compensating donor defects in NH3-MBE-grown Mg-doped GaN films. High-quality p-n junctions with very low reverse current and close to unity ideality factor were also grown and investigated. For the design of heterojunction devices such as laser diodes, light emitting diodes or heterojunction bipolar transistors, hetero-interface's characteristics such as the band offset or interface charges are fundamental. A technique developed by Kroemer et al. uses capacitance-voltage (C-V) profiling to extract band-offsets and charges at a hetero-interface. We applied this technique to the III-Nitrides. We discovered that for the polar III-Nitrides, the technique is not applicable because of the very large polarization charge. We nevertheless successfully measured the polarization charge at the AlGaN/GaN hetero

  6. Electro-Optical Characteristics of P+n In0.53Ga0.47As Hetero-Junction Photodiodes in Large Format Dense Focal Plane Arrays

    Science.gov (United States)

    DeWames, R.; Littleton, R.; Witte, K.; Wichman, A.; Bellotti, E.; Pellegrino, J.

    2015-08-01

    This paper is concerned with focal plane array (FPA) data and use of analytical and three-dimensional numerical simulation methods to determine the physical effects and processes limiting performance. For shallow homojunction P+n designs the temperature dependence of dark current for T dark currents are generation and recombination (G-R) currents originating in the depletion regions of the double layer planar heterostructure (DLPH) photodiode. In the analytical model differences from bulk G-R behavior are modeled with a G-R like perimeter-dependent shunt current conjectured to originate at the InP/InGaAs interface. In this description the fitting property is the effective conductivity, σ eff( T), in mho cm-1. Variation in the data suggests σ eff (300 K) values of 1.2 × 10-11-4.6 × 10-11 mho cm-1). Substrate removal extends the quantum efficiency (QE) spectral band into the visible region. However, dead-layer effects limit the QE to 10% at a wavelength of 0.5 μm. For starlight-no moon illumination conditions, the signal-to-noise ratio is estimated to be 50 at an operating temperature of 300 K. A major result of the 3D numerical simulation of the device is the prediction of a perimeter G-R current not associated with the properties of the metallurgical interface. Another is the prediction that for a junction positioned in the larger band gap InP cap layer the QE is bias-dependent and that a relatively large reverse bias ≥0.9 V is needed for the QE to saturate to the shallow homojunction value. At this higher bias the dark current is larger than the shallow homojunction value. The 3D numerical model and the analytical model agree in predicting and explaining the measured radiatively limited diffusion current originating at the n-side of the junction. The calculations of the area-dependent G-R current for the condition studied are also in agreement. Unique advantages of the 3D numerical simulation are the ability to mimic real device structures, achieve deeper

  7. NOx, NH3, N2O and PN real driving emissions from a Euro VI heavy-duty vehicle. Impact of regulatory on-road test conditions on emissions.

    Science.gov (United States)

    Mendoza-Villafuerte, Pablo; Suarez-Bertoa, Ricardo; Giechaskiel, Barouch; Riccobono, Francesco; Bulgheroni, Claudia; Astorga, Covadonga; Perujo, Adolfo

    2017-12-31

    Euro VI emission standards for heavy-duty vehicles (HDVs) introduced for the first time limits for solid particle number (PN) and NH3 emissions. EU regulation also includes a Portable Emissions Measurement System (PEMS) based test at type approval, followed by in-service conformity (ISC) testing. A comprehensive study on the real-time on-road emissions of NOx, NH3, N2O and PN from a Euro VI HDV equipped with a Diesel Oxidation Catalyst (DOC), a Diesel Particle Filter (DPF), a Selective Catalytic Reduction (SCR) system and an Ammonia Oxidation Catalyst (AMOX) is presented. Our analyses revealed that up to 85% of the NOx emissions measured during the tests performed are not taken into consideration if the boundary conditions for data exclusion set in the current legislation are applied. Moreover, it was found that the highest NOx emissions were measured during urban operation. Analyses show that a large fraction urban of operation is not considered when 20% power threshold as boundary condition is applied. They also show that cold start emissions account for a large fraction of the total NOx emitted. Low emissions of PN (2.8×10(10) to 6.5×10(10)#/kWh) and NH3 (1.0 to 2.2ppm) were obtained during the on-road tests, suggesting effectiveness of the vehicle's after-treatment (DPF and AMOX). Finally, a comparison between speed-based (as currently defined by Euro VI legislation) and land-use-based (using Geographic Information System (GIS)) calculation of shares of operation was performed. Results suggest that using GIS to categorize the shares of operation could result in different interpretations depending on the criteria adopted for their definition. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  8. Integrated Advanced Microwave Sounding Unit-A (AMSU-A). Performance Verification Report: Initial Comprehensive Performance Test Report, P/N 1331200-2-IT, S/N 105/A2

    Science.gov (United States)

    Platt, R.

    1999-01-01

    This is the Performance Verification Report, Initial Comprehensive Performance Test Report, P/N 1331200-2-IT, S/N 105/A2, for the Integrated Advanced Microwave Sounding Unit-A (AMSU-A). The specification establishes the requirements for the Comprehensive Performance Test (CPT) and Limited Performance Test (LPT) of the Advanced Microwave Sounding, Unit-A2 (AMSU-A2), referred to herein as the unit. The unit is defined on Drawing 1331200. 1.2 Test procedure sequence. The sequence in which the several phases of this test procedure shall take place is shown in Figure 1, but the sequence can be in any order.

  9. Studi d'idoneità ambientale su grande scala a fini conservazionistici: il caso del Capriolo italico nel P.N. del Pollino

    Directory of Open Access Journals (Sweden)

    Alessandro Massolo

    2003-10-01

    formulati hanno dato risultati soddisfacenti (> 70% di classificazioni corrette, ma alla verifica sui dati del PN del Pollino, solo il modello formulato con la regressione logistica e gli indici di paesaggio come variabili predittive, ha mostrato una potente capacità predittiva (89% degli avvistamenti e dei dati di presenza/assenza, classificando come idoneo per la specie circa il 59% del territorio del Parco. Il nostro studio suggerisce che vi sono casi in cui, nonostante le difficoltà insite nell?applicazione di un modello in aree differenti (soprattutto in termini di orografia e vegetazione da quella di origine dei dati, le caratteristiche di complessità e frammentazione del territorio a grande scala permettono la formulazione di un modello adeguato e potente. Infine, riteniamo che, senza un?adeguata valutazione su dati provenienti dall?area d?applicazione, le predizioni dei modelli possano dare risultati non coerenti con la distribuzione reale della popolazione in esame, suggerendo cautela nelle previsioni in aree in cui la specie sia assente.

  10. Two-step hydrothermal synthesis of novel hierarchical Co3O4/Bi2O2CO3p-n heterojunction composite photocatalyst with enhanced visible light photocatalytic activity

    Science.gov (United States)

    Yang, Chunming; Gao, Guimei; Guo, Zhifeng; Song, Litao; Chi, Junzhou; Gan, Shucai

    2017-04-01

    A hierarchical flower-like Co3O4/Bi2O2CO3 composite photocatalyst with a p-n heterojunction semiconductor structure has been synthesized via two-step hydrothermal process. The composite photocatalyst have been characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM) and high-resolution transmission electron microscopy (HRTEM), BET surface area, UV-vis diffuse reflectance spectra (DRS), electron spin resonance (ESR) and photoluminescence spectroscopy (PL). The photocatalyst exhibits enhanced photocatalytic activity for methyl orange (MO) degradation under visible light irradiation. The ESR results reveal that the superoxide radicals (rad O2-) were the main active species in the photocatalytic system. The 0.6 wt% Co3O4/Bi2O2CO3 exhibits the highest photocatalytic activity as compared with other samples because of the formation of the p-n junction between p-Co3O4 and n-Bi2O2CO3, which effectively suppresses the recombination of photoinduced electron-hole pairs and increase of the concentration of superoxide radicals (rad O2-) involving in the photodegradation process. Moreover, the mechanism of the enhanced photocatalytic properties was proposed.

  11. High efficient photocatalytic activity from nanostructuralized photonic crystal-like p-n coaxial hetero-junction film photocatalyst of Cu3SnS4/TiO2 nanotube arrays

    Science.gov (United States)

    Li, Yan; Liu, Fang-Ting; Chang, Yin; Wang, Jian; Wang, Cheng-Wei

    2017-12-01

    Structuring the materials in the form of photonic crystals is a new strategy for photocatalytic applications. Herein, a new concept of photonic crystal-induced p-n coaxial heterojunction film photocatalyst of Cu3SnS4/TiO2 (CTS/PhC-TNAs) was well-designed and successfully fabricated by combining periodic pulse anodic oxidation and in-situ self-assembling methods Such nanostructured CTS/PhC-TNAs exhibited significantly improved photocatalytic degradation activity under simulated sunlight irradiation with methyl orange (MO) as the target pollutants. Within 120 min, 82% of the MO (10 mg/L) was photodegraded and its kinetic constant per specific surface area reached 0.05332 μmol/m2h, which is 1.6 and 12.8 times more quickly than that of PhC-TNAs and CTS, respectively. Its significantly enhanced photocatalytic activity could be mainly attributed to a joint effect of the unique photonic crystal property of PhC-TNAs and the nanostructured hollow p-n coaxial hetero-junction, which result in an increased efficiency of charge separation and transfer and also an improved spectral response capability. This photonic crystal film photocatalyst has the potential for enhancing the photocatalytic activity via further optimizing the photonic stop band of PhC-TNAs. The study presents a new means to design the kind of photonic crystal structural-induced novel photocatalysts with high photocatalytic activities in pollution treatment.

  12. The Role of Postmastectomy Radiation Therapy After Neoadjuvant Chemotherapy in Clinical Stage II-III Breast Cancer Patients With pN0: A Multicenter, Retrospective Study (KROG 12-05)

    Energy Technology Data Exchange (ETDEWEB)

    Shim, Su Jung [Department of Radiation Oncology, Eulji General Hospital, College of Medicine, Eulji University, Seoul (Korea, Republic of); Park, Won, E-mail: wonro.park@samsung.com [Department of Radiation Oncology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of); Huh, Seung Jae; Choi, Doo Ho [Department of Radiation Oncology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of); Shin, Kyung Hwan [Proton Therapy Center, Research Institute and Hospital, National Cancer Center, Goyang (Korea, Republic of); Lee, Nam Kwon [Proton Therapy Center, Research Institute and Hospital, National Cancer Center, Goyang (Korea, Republic of); Department of Radiation Oncology, Korea Medical Center, Korea University, School of Medicine, Seoul (Korea, Republic of); Suh, Chang-Ok; Keum, Ki Chang; Kim, Yong Bae [Department of Radiation Oncology, Yonsei Cancer Center, Severance Hospital, Yonsei University College of Medicine, Seoul (Korea, Republic of); Ahn, Seung Do; Kim, Su Ssan [Department of Radiation Oncology, Asan Medical Center, University of Ulsan, College of Medicine, Seoul (Korea, Republic of); Ha, Sung W.; Chie, Eui Kyu; Kim, Kyubo [Department of Radiation Oncology, Seoul National University College of Medicine, Seoul (Korea, Republic of); Shin, Hyun Soo [Department of Radiation Oncology, Bundang CHA Hospital, School of Medicine, CHA University, Seongnam (Korea, Republic of); Kim, Jin Hee [Department of Radiation Oncology, Dongsan Medical Center, Keimyung University School of Medicine, Daegu (Korea, Republic of); Lee, Hyung-Sik [Department of Radiation Oncology, Dong-A University Hospital, Dong-A University School of Medicine, Busan (Korea, Republic of)

    2014-01-01

    Purpose: The purpose of this study was to investigate the role of postmastectomy radiation therapy (PMRT) after neoadjuvant chemotherapy (NAC) in clinical stage II-III breast cancer patients with pN0. Methods and Materials: We retrospectively identified 417 clinical stage II-III breast cancer patients who achieved an ypN0 at surgery after receiving NAC between 1998 and 2009. Of these, 151 patients underwent mastectomy after NAC. The effect of PMRT on disease-free survival (DFS), locoregional recurrence-free survival (LRRFS), and overall survival (OS) was evaluated by multivariate analysis including known prognostic factors using the Kaplan-Meier method and compared using the log–rank test and Cox proportional regression analysis. Results: Of the 151 patients who underwent mastectomy, 105 (69.5%) received PMRT and 46 patients (30.5%) did not. At a median follow-up of 59 months, 5 patients (3.3%) developed LRR (8 sites of recurrence) and 14 patients (9.3%) developed distant metastasis. The 5-year DFS, LRRFS, and OS rates were 91.2, 98.1, and 93.3% with PMRT and 83.0%, 92.3%, and 89.9% without PMRT, respectively (all P values not significant). By univariate analysis, only age (≤40 vs >40 years) was significantly associated with decreased DFS (P=.027). By multivariate analysis, age (≤40 vs >40 years) and pathologic T stage (0-is vs 1 vs 2-4) were significant prognostic factors affecting DFS (hazard ratio [HR] 0.353, 95% confidence interval [CI] 0.135-0.928, P=.035; HR 2.223, 95% CI 1.074-4.604, P=.031, respectively). PMRT showed no correlation with a difference in DFS, LRRFS, or OS by multivariate analysis. Conclusions: PMRT might not be necessary for pN0 patients after NAC, regardless of clinical stage. Prospective randomized clinical trial data are needed to assess whether PMRT can be safely omitted in pN0 patients after NAC and mastectomy for clinical stage II-III breast cancer.

  13. Construction of ZnO/ZnS/CdS/CuInS₂ core-shell nanowire arrays via ion exchange: p-n junction photoanode with enhanced photoelectrochemical activity under visible light.

    Science.gov (United States)

    Yu, Yu-Xiang; Ouyang, Wei-Xin; Liao, Zhou-Ting; Du, Bin-Bin; Zhang, Wei-De

    2014-06-11

    ZnO/ZnS/CdS/CuInS2 core-shell nanowire arrays with enhanced photoelectrochemical activity under visible light were successfully prepared via ion exchange and hydrothermal methods. The samples were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, UV-vis absorption, X-ray photoemission spectroscopy, and photoelectrochemical response. As a p-n junction photoanode, ZnO/ZnS/CdS/CuInS2 heterostructure shows much higher visible light photoelectrocatalytic activity toward water splitting than ZnO/ZnS/CdS and ZnO/ZnS films. The ZnO/ZnS/CdS/CuInS2 film with optimal constitution exhibits the highest photocurrent of 10.5 mA/cm(2) and the highest IPCE of approximately 57.7% at 480 nm and a bias potential of 0 V versus Ag/AgCl. The critical roles of CdS and ZnS in ZnO/ZnS/CdS/CuInS2 heterostructure were investigated. ZnS, as a passivation layer, suppresses the recombination of the photogenerated charge carriers at the interface of the oxide and CuInS2. CdS enhances the absorption of visible light and forms p-n junctions with CuInS2, which promotes the transport of charge carriers and retards the recombination of electrons and holes in CuInS2 to improve the photoelectrochemical performance of ZnO/ZnS/CdS/CuInS2 heterostructure.

  14. Two-step hydrothermal synthesis of novel hierarchical Co{sub 3}O{sub 4}/Bi{sub 2}O{sub 2}CO{sub 3}p-n heterojunction composite photocatalyst with enhanced visible light photocatalytic activity

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Chunming [College of Chemistry, Jilin University, Changchun 130026 (China); Shen Hua Zhun Neng Resources Comprehensive Development Company Limited, zhungeer 010300 (China); Gao, Guimei, E-mail: gaoguimei_gao@163.com [Shen Hua Zhun Neng Resources Comprehensive Development Company Limited, zhungeer 010300 (China); Guo, Zhifeng; Song, Litao; Chi, Junzhou [Shen Hua Zhun Neng Resources Comprehensive Development Company Limited, zhungeer 010300 (China); Gan, Shucai, E-mail: gansc@jlu.edu.cn [College of Chemistry, Jilin University, Changchun 130026 (China)

    2017-04-01

    Highlights: • Unique chrysanthemum-like Co{sub 3}O{sub 4}/Bi{sub 2}O{sub 2}CO{sub 3} photocatalyst was synthesized by two-step hydrothermal process. • The Co{sub 3}O{sub 4}/Bi{sub 2}O{sub 2}CO{sub 3} composites showed superior photocatalytic activity and stability. • The mechanism of the high performance was proposed as well. - Abstract: A hierarchical flower-like Co{sub 3}O{sub 4}/Bi{sub 2}O{sub 2}CO{sub 3} composite photocatalyst with a p-n heterojunction semiconductor structure has been synthesized via two-step hydrothermal process. The composite photocatalyst have been characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM) and high-resolution transmission electron microscopy (HRTEM), BET surface area, UV–vis diffuse reflectance spectra (DRS), electron spin resonance (ESR) and photoluminescence spectroscopy (PL). The photocatalyst exhibits enhanced photocatalytic activity for methyl orange (MO) degradation under visible light irradiation. The ESR results reveal that the superoxide radicals (·O{sub 2}{sup −}) were the main active species in the photocatalytic system. The 0.6 wt% Co{sub 3}O{sub 4}/Bi{sub 2}O{sub 2}CO{sub 3} exhibits the highest photocatalytic activity as compared with other samples because of the formation of the p-n junction between p-Co{sub 3}O{sub 4} and n-Bi{sub 2}O{sub 2}CO{sub 3}, which effectively suppresses the recombination of photoinduced electron-hole pairs and increase of the concentration of superoxide radicals (·O{sub 2}{sup −}) involving in the photodegradation process. Moreover, the mechanism of the enhanced photocatalytic properties was proposed.

  15. Creation of Cu2O@TiO2 composite photocatalysts with p-n heterojunctions formed on exposed Cu2O facets, their energy band alignment study, and their enhanced photocatalytic activity under illumination with visible light.

    Science.gov (United States)

    Liu, Lingmei; Yang, Weiyi; Sun, Wuzhu; Li, Qi; Shang, Jian Ku

    2015-01-28

    The creation of photocatalysts with controlled facets has become an important approach to enhance their activity. However, how the formation of heterojunctions on exposed facets could affect their photocatalytic performance ranking had not yet been investigated. In this study, Cu2O@TiO2 core-shell structures were created, and Cu2O/TiO2 p-n heterojunctions were formed on various exposed facets of Cu2O cubes, Cu2O cuboctahedra, and Cu2O octahedra, respectively. These Cu2O@TiO2 polyhedra demonstrated an enhanced photocatalytic degradation effect on Methylene Blue (MB) and 4-nitrophenol (4-NP) under visible light illumination, because of the enhanced charge carrier separation by the formation of Cu2O@TiO2 p-n heterojunctions. It was further found that their photocatalytic performance was also facet-dependent as pure Cu2O polyhedra, while the photocatalytic performance ranking of these Cu2O@TiO2 polyhedra was different with that of their corresponding Cu2O polyhedron cores. By the combination of optical property measurement and XPS analysis, the energy band alignments of these Cu2O@TiO2 polyhedra were determined, which demonstrated that Cu2O@TiO2 octahedra had the highest band offset for the separation of charge carriers. Thus, the charge-carrier-separation-driven force in Cu2O@TiO2 polyhedra was different from their corresponding Cu2O polyhedron cores, which resulted in their different surface photovoltage spectrum (SPS) responses and different photocatalytic performance rankings.

  16. A Au/Cu2O-TiO2 system for photo-catalytic hydrogen production. A pn-junction effect or a simple case of in situ reduction?

    KAUST Repository

    Sinatra, Lutfan

    2015-02-01

    Photo-catalytic H2 production from water has been studied over Au-Cu2O nanoparticle deposited on TiO2 (anatase) in order to probe into both the plasmon resonance effect (Au nanoparticles) and the pn-junction at the Cu2O-TiO2 interface. The Au-Cu2O composite is in the form of ∼10 nm Au nanoparticles grown on ∼475 nm Cu2O octahedral nanocrystals with (111) facets by partial galvanic replacement. X-ray Photoelectron Spectroscopy (XPS) Cu2p and Auger L3M4,5M4,5 lines indicate that the surface of Cu2O is mainly composed of Cu+. The rate for H2 production (from 95 water/5 ethylene glycol; vol.%) over 2 wt.% (Au/Cu2O)-TiO2 is found to be ∼10 times faster than that on 2 wt.% Au-TiO2 alone. Raman spectroscopy before and after reaction showed the disappearance of Cu+ lines (2Eu) at 220 cm-1. These observations coupled with the induction time observed for the reaction rate suggest that in situ reduction from Cu+ to Cu0 occurs upon photo-excitation. The reduction requires the presence of TiO2 (electron transfer). The prolonged activity of the reaction (with no signs of deactivation) despite the reduction to Cu0 indicates that the latter takes part in the reaction by providing additional sites for the reaction, most likely as recombination centers for hydrogen atoms to form molecular hydrogen. This phenomenon provides an additional route for enhancing the efficiency and lifetime of Cu2O-TiO2 photocatalytic systems, beyond the usually ascribed pn-junction effect.

  17. The highly enhanced visible light photocatalytic degradation of gaseous o-dichlorobenzene through fabricating like-flowers BiPO{sub 4}/BiOBr p-n heterojunction composites

    Energy Technology Data Exchange (ETDEWEB)

    Zou, Xuejun [Department of Environmental Science and Technology, Dalian Nationalities University, Dalian, 116600 (China); Dong, Yuying, E-mail: dongy@dlnu.edu.cn [Department of Environmental Science and Technology, Dalian Nationalities University, Dalian, 116600 (China); Zhang, Xiaodong, E-mail: fatzhxd@126.com [Environment and Low-Carbon Research Center, School of Environment and Architecture, University of Shanghai for Science and Technology, Shanghai, 200093 (China); Cui, Yubo; Ou, Xiaoxia [Department of Environmental Science and Technology, Dalian Nationalities University, Dalian, 116600 (China); Qi, Xiaohui [College of Life Science, Dalian Nationalities University, Dalian, 116600 (China)

    2017-01-01

    Highlights: • Like-flowers BiPO{sub 4}/BiOBr was fabricated by mixing in solvent method. • o-Dichlorobenzene removal efficiency was 53.6% using BiPO{sub 4}/BiOBr. • The p–n junction improved o-dichlorobenzene degradation activity. - Abstract: In this paper, in order to enhance photo-induced electron-hole pairs separation of BiOBr, flowers-like BiPO{sub 4}/BiOBr p-n heterojunction composites was fabricated by a mixing in solvent method. The as-prepared samples were characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), high resolution transmission electron microscopy (HRTEM), UV–vis absorption spectroscopy (DRS), X-ray photoelectron spectroscopy (XPS), and N{sub 2} adsorption-desorption. Meanwhile, their photocatalytic properties were investigated by the degradation of gaseous o-dichlorobenzene under visible light irradiation. Due to its strong adsorption capacity and the formation of p-n heterojunction, compared with BiPO{sub 4} and BiOBr, the BiPO{sub 4}/BiOBr composites showed higher photocatalytic activity in the degradation of gaseous o-DCB under visible light. Among them, 2% BiPO{sub 4}/BiOBr showed the maximum value of the activity, whose degradation rate was about 2.6 times as great as the pure BiOBr. Furthermore, the OH· was confirmed the main active species during the photocatalytic process by the trapping experiments. The outstanding performance indicated that the photocatalysts could be applied to air purification for chlorinated volatile organic compound.

  18. Cutaneous sporotrichosis: Unusual clinical presentations

    Directory of Open Access Journals (Sweden)

    Mahajan Vikram

    2010-01-01

    Full Text Available Three unusual clinical forms of sporotrichosis described in this paper will be a primer for the clinicians for an early diagnosis and treatment, especially in its unusual presentations. Case 1, a 52-year-old man, developed sporotrichosis over pre-existing facial nodulo-ulcerative basal cell carcinoma of seven-year duration, due to its contamination perhaps from topical herbal pastes and lymphocutaneous sporotrichosis over right hand/forearm from facial lesion/herbal paste. Case 2, a 25-year-old woman, presented with disseminated systemic-cutaneous, osteoarticular and possibly pleural (effusion sporotrichosis. There was no laboratory evidence of tuberculosis and treatment with anti-tuberculosis drugs (ATT did not benefit. Both these cases were diagnosed by histopathology/culture of S. schenckii from tissue specimens. Case 3, a 20-year-old girl, had multiple intensely pruritic, nodular lesions over/around left knee of two-year duration. She was diagnosed clinically as a case of prurigo nodularis and histologically as cutaneous tuberculosis, albeit, other laboratory investigations and treatment with ATT did not support the diagnosis. All the three patients responded well to saturated solution of potassium iodide (SSKI therapy. A high clinical suspicion is important in early diagnosis and treatment to prevent chronicity and morbidity in these patients. SSKI is fairly safe and effective when itraconazole is not affordable/ available.

  19. Effectiveness of Topical Chia Seed Oil on Pruritus of End-stage Renal Disease (ESRD) Patients and Healthy Volunteers.

    Science.gov (United States)

    Jeong, Se Kyoo; Park, Hyun Jung; Park, Byeong Deog; Kim, Il-Hwan

    2010-05-01

    Several studies have been performed to evaluate the efficacy of dietary n-3 fatty acid for patients with renal dysfunction. While about 40% to 80% of patients with end-stage renal disease (ESRD) complain about pruritus and xerosis, there are few reports on the effects of topical n-3 fatty acid on these symptoms. In order to investigate the possible beneficial effects of topical n-3 fatty acid, oils extracted from chia (Salvia hispanica) seed were formulated into topical products, the effects of which were measured. Five healthy volunteers having xerotic pruritus symptoms and 5 patients with pruritus caused by either ESRD or diabetes were involved in this study. A topical formulation containing 4% chia seed oils were applied for an 8-week duration. Subjective itching symptoms were assessed on a 6-point scale, as were other skin functions, namely transepidermal water loss and skin capacitance. After the 8 weeks of application, significant improvements in skin hydration, lichen simplex chronicus, and prurigo nodularis were observed in all patients. A similar improvement was also observed among healthy volunteers with xerotic pruritus. Improvement of epidermal permeability barrier function and skin hydration, represented by trans-epidermal water loss and skin capacitance, respectively, were also observed. No adverse effects were observed in all the tested patients and volunteers. Chia seed oil can be used as an adjuvant moisturizing agent for pruritic skin, including that of ESRD patients.

  20. De novo HIV infection diagnoses in a Department of Dermatology and Venereology in Lisbon, Portugal.

    Science.gov (United States)

    Mendes-Bastos, Pedro; Brasileiro, Ana; Matos-Pires, Eugénia; Rodrigues, Isaura; Marques, Cristina; Coelho-Macias, Vasco; Fernandes, Cândida

    2017-08-01

    Background Portugal has the highest prevalence rate of HIV infection in Western Europe. The proportion of patients with a late diagnosis, carried out in full-blown AIDS stage, remains high. Skin and mucous membrane manifestations are not rare in these patients. Objective A demographic, clinical, and laboratorial characterization of patients with de novo HIV infection diagnosis made in the Department of Dermatology and Venereology of a central hospital in Lisbon, Portugal. Methods Retrospective review of medical records of adult patients newly diagnosed with HIV infection (reactive immunoassay for antibodies to HIV-1/HIV-2 or HIV p24 antigen) in the Dermatology and Venereology Department of a Portuguese central hospital in the period between January 2005 and December 2013. Results During the study period, 97 new cases were diagnosed, 70 men and 27 women. The median age at diagnosis was 36 years. Of the total, 50 cases were diagnosed with a concomitant sexually transmitted infection (STI), more frequently syphilis and ano-genital HPV infection. The remaining 47 patients were diagnosed with other dermatological conditions such as prurigo nodularis, psoriasis, and Kaposi's sarcoma. The duration of complaints that lead to medical attention ranged from HIV infection diagnoses performed by dermatovenereologists in a central hospital in Lisbon, Portugal. As in the past, the importance of Dermato-Venereology for HIV infection diagnosis remains present in daily clinical practice.

  1. Effects of miglustat treatment in a patient affected by an atypical form of Tangier disease.

    Science.gov (United States)

    Sechi, Annalisa; Dardis, Andrea; Zampieri, Stefania; Rabacchi, Claudio; Zanoni, Paolo; Calandra, Sebastiano; De Maglio, Giovanna; Pizzolitto, Stefano; Maruotti, Valerio; Di Muzio, Antonio; Platt, Frances; Bembi, Bruno

    2014-09-18

    Tangier disease (TD) is a rare autosomal recessive disorder, resulting from mutations in the ATP binding cassette transporter (ABCA1) gene. The deficiency of ABCA1 protein impairs high density lipoprotein (HDL) synthesis and cholesterol esters trafficking. A 58 year-old female, presenting with complex clinical signs (splenomegaly, dysarthria, dysphagia, ataxia, tongue enlargement, prurigo nodularis, legs lymphedema, pancytopenia and bone marrow foam cells), was misdiagnosed as Niemann-Pick C (NPC) and treated with miglustat (300 mg/day), normalizing neurological symptoms and improving skin lesions and legs lymphedema. Subsequently filipin-staining and molecular analysis for NPC genes were negative. Lipid profiling showed severe deficiency of HDL, 2 mg/dl (n.v. 45-65) and apoAI, 5.19 mg/dl (n.v. 110-170), suggesting TD as a probable diagnosis. Molecular analysis of ABCA1 gene showed the presence of a novel homozygous deletion (c.4464-486_4698 + 382 Del). Miglustat treatment was then interrupted with worsening of some neurological signs (memory defects, slowing of thought processes) and skin lesions. Treatment was restarted after 7 months with neurological normalization and improvement of skin involvement. These results suggest miglustat as a possible therapeutic approach in this untreatable disease. The mechanisms by which miglustat ameliorates at least some clinical manifestations of TD needs to be further investigated.

  2. From the brain-skin connection: the neuroendocrine-immune misalliance of stress and itch.

    Science.gov (United States)

    Arck, Petra; Paus, Ralf

    2006-01-01

    Perceived stress has long been allied with disturbances of the dynamic equilibrium established between the nervous, endocrine and immune systems, thus triggering or aggravating disease manifestation. Several common skin diseases are now acknowledged to be worsened by psychological stress, particularly immunodermatoses such as atopic dermatitis, psoriasis, seborrheic eczema, prurigo nodularis, lichen planus, chronic urticaria, alopecia areata and pruritus sine materia. Itch (pruritus) is perhaps the most common symptom associated with a majority of these inflammatory skin diseases, and acute as well as chronic stress perceptions are recognized to trigger or enhance pruritus. A wealth of mediators released systemically or locally in the skin in response to stress increase sensory innervation, upregulate the production of other pruritogenic agents, perpetuate (neurogenic) inflammation and lower the itch threshold. In the present review, we explore recent frontiers in both stress and pruritus research and portray the perpetuation of chronic skin inflammation and itch as a neuroendocrine-immune 'misalliance'. We argue that key candidate molecules of the stress response with strong pruritogenic potential, such as nerve growth factor, corticotropin-releasing hormone and substance P, and mast cells, which may be considered as 'central cellular switchboards of pruritogenic inflammation', need to be further explored systematically in order to develop more effective therapeutic combination strategies for itch management in chronic, stress-vulnerable inflammatory skin diseases. Copyright (c) 2006 S. Karger AG, Basel.

  3. [Intrahepatic cholestasis of pregnancy : Rare but important].

    Science.gov (United States)

    Kremer, A E; Wolf, K; Ständer, S

    2017-02-01

    Intrahepatic cholestasis of pregnancy (ICP) is a liver-specific disorder occurring in approximately 0.5-2.0% of all pregnancies with a considerable variation in certain ethnic groups. ICP usually runs a benign course for the mother and is characterized by maternal pruritus mainly in the third trimester, elevated transaminases and fasting total serum bile salts and increased fetal adverse events. The etiology of ICP is only partially understood but seems to be multifactorial. Cholestasis-inducing effects of certain female sex hormones and their metabolites play an important role in genetically susceptible women. The mechanisms resulting in fetal complications such as spontaneous preterm labour, antepartum passage of meconium, asphyxia events, still birth and fetal death are not well understood. Certain sulfated progesterone metabolites are likely to play a role in the pathogenesis of pruritus in ICP. In contrast to pregnancy-related dermatoses, pruritus does not present with primary skin alterations. However, intense scratching may cause secondary skin changes such as abrasions, excoriations and sometimes prurigo nodularis. Treatment is based on ursodeoxycholate treatment to reduce pruritus and hepatic impairment as well as elective delivery between gestation week 37-38 to pre-empt potential stillbirths. This article reviews clinical symptoms, diagnosis, treatment and in particular pathogenesis of pruritus in ICP.

  4. Measurement of the reactions K/sup +/d to K/sup +/d and K/sup +/d to K /sup +/pn and an investigation of elastic K/sup +/-nucleon scattering at 46 GeV/c

    CERN Document Server

    Dehm, G; Göbel, G; Wittek, W; Wolf, G

    1975-01-01

    The coherent elastic reaction K/sup +/d to K/sup +/d and the break-up reaction K/sup +/d to K/sup +/pn are st studied in a K/sup +/d experiment at 4.6 GeV/c with the CERN 2 m bubble chamber. Partial and differential cross sections are given and the slopes of the differential cross sections are determined. The results for the reaction K/sup +/d to K/sup +/p(n/sub s/), where n/sub s/ denotes the spectator neutron, are compared with those of the reaction K/sup +/p to K/sup o/pp and K/sup +/p to K/sup +/p, parameters of the elastic K /sup +/-nucleon scattering at 4.6 GeV/c are determined in the framework of the Glauber model. The D-wave of the deuteron and spin- flip effects are taken into account. (17 refs).

  5. Resonances in the System of \\pi^{+}\\pi^{-}-Mesons from np\\to np\\pi^{+}\\pi^{-} Reaction at P_{n}=5.20 GeV\\/c Search, Results of Direct Observations, Interpretation

    CERN Document Server

    Troyan, Yu A; Pechenov, V N; Troyan, Yu A; Belyaev, A V; Jerusalimov, A P; Arakelian, S G

    2002-01-01

    Ten resonances were found in the mass spectrum of \\pi^{+}\\pi^{-} system based on 66075 events from np\\to np\\pi^{+}\\pi^{-} reaction in np-interactions at P_{n}=(5.20\\pm0.16) GeV/c in the one-meter hydrogen bubble chamber of the LHE (JINR) by using the criterion cos\\Theta^{*}p>0. These masses are the following: (347\\pm12), (418\\pm6), (511\\pm12), (610\\pm5), (678\\pm17), (757\\pm5), (880\\pm12), (987\\pm12), (1133\\pm15), and (1285\\pm22) MeV/c^{2}; their excesses above the background are 2.9, 5.2, 3.5, 1.4, 2.0, 8.5, 4.8, 3.8, 5.2, and 6.0 standard deviations, respectively. The experimental widths of the resonances vary within the region from 16 to 94 MeV/c^{2}. Such effects were not found in \\pi^{-}\\pi^{0} combinations from np\\to pp\\pi^{-}\\pi^0 reaction. Therefore, it is necessary to attribute the value of isotopic spin I=0 to the resonances found in the mass spectrum of the \\pi^{+}\\pi^{-} system. The spin was estimated for the most statistically provided resonances at masses of 418, 511 and 757 MeV/c^{2}. We determi...

  6. 100-MeV proton beam intensity measurement by Au activation analysis using {sup 197}Au(p, pn){sup 196}Au and {sup 197}Au(p, p3n){sup 194}Au reactions

    Energy Technology Data Exchange (ETDEWEB)

    Mokhtari Oranj, Leila [Division of Advanced Nuclear Engineering, POSTECH, Pohang 37673 (Korea, Republic of); Jung, Nam-Suk; Oh, Joo-Hee [Pohang Accelerator Laboratory, POSTECH, Pohang 37673 (Korea, Republic of); Lee, Hee-Seock, E-mail: lee@postech.ac.kr [Pohang Accelerator Laboratory, POSTECH, Pohang 37673 (Korea, Republic of)

    2016-05-15

    The proton beam intensity of a 100-MeV proton linac at the Korea Multi-purpose Accelerator Complex (KOMAC) was measured by an Au activation analysis using {sup 197}Au(p, pn){sup 196}Au and {sup 197}Au(p, p3n){sup 194}Au reactions to determine the accuracy and precision of beam intensity measurement using Gafchromic film dosimetry method. The target, irradiated by 100-MeV protons, was arranged in a stack consisting of Au, Al foils and Pb plates. The yields of produced radio-nuclei in Au foils were obtained by gamma-ray spectroscopy. The FLUKA code was employed to calculate the energy spectrum of protons onto the front surface of Au foils located at three different depth points of the target and also to investigate the condition of incident beam on the target. A good agreement was found between the beam intensity measurements using the activation analysis method at three different depth points of the target. An excellent agreement was also observed between the beam intensity measurements using the Au activation analysis method and the dosimetry method using Gafchromic film.

  7. Investigation of the 66Zn(p,2pn) 64Cu and 68Zn(p,x) 64Cu nuclear processes up to 100 MeV: Production of 64Cu

    Science.gov (United States)

    Szelecsényi, F.; Steyn, G. F.; Kovács, Z.; Vermeulen, C.; van der Meulen, N. P.; Dolley, S. G.; van der Walt, T. N.; Suzuki, K.; Mukai, K.

    2005-11-01

    Cross-sections of the 66Zn(p,2pn)64Cu and 68Zn(p,x)64Cu nuclear processes were measured on highly enriched zinc targets using the stacked-foil activation technique up to 100 MeV. The new cross-sections were compared to literature data. The optimum energy range for production of 64Cu was found to be 70 → 35 MeV on 66Zn and 37 → 20 MeV on 68Zn. The thick-target yields were determined as 777 MBq/μAh (21.0 mCi/μAh) and 185 MBq/μAh (5.0 mCi/μAh), respectively. The yields of the longer-lived contaminant copper radioisotopes (i.e. 61Cu when using 66Zn as target material and both 61Cu and 67Cu in the case of 68Zn target material) were also calculated. The results obtained from the present study indicate that both reactions are suited for the production of 64Cu at a medium energy cyclotron. The optimum energy ranges are also complementary therefore the potential to utilize tandem targetry exists.

  8. β{sup -} transitions of {sub 7}{sup 16}N{sub 9} → {sub 8}{sup 16}O{sub 8} with optimized SDI residual interaction using pnTDA and TDA approximations

    Energy Technology Data Exchange (ETDEWEB)

    Pahlavani, M.R.; Firoozi, B. [University of Mazandaran, Department of Nuclear Physics, Faculty of Basic Science, P.O. Box 47415-416, Babolsar (Iran, Islamic Republic of)

    2015-11-15

    Within a developed particle-hole approach, a systematic study of the β{sup -} transition from the ground state of the {sup 16}N nucleus to the ground and some exited states of the {sup 16}O nucleus has been carried out. The energy spectrum and the wave functions of pure configuration of the {sup 16}N and {sup 16}O nuclei are numerically obtained using the mean-field shell model with respect to the Woods-Saxon nuclear potential accompanying spin-orbit and Coulomb interaction. Considering SDI residual interaction, mixed configuration of ground and excited pnTDA and TDA states are extracted for the aforementioned nucleus. These energy spectra and corresponding eigenstates are highly correspondent to the experimental energy spectrum and eigenstates after adjusting the residual potential parameters using the Nelder-Mead (NM) algorithm. In this approach, the endpoint energy, log ft and the partial half-lives of some possible transitions are calculated. The obtained results using the optimized SDI approach are reasonably close to the available experimental data. (orig.)

  9. Spin-flip (p,n) reactions on /sup 26/Mg, /sup 54/Fe, and /sup 56/Fe at selected proton bombarding energies in the range of 17 to 25 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Aron, D.L.

    1985-06-01

    New data are presented for the /sup 26/Mg(p,n)/sup 26/Al reaction at E/sub p/ = 19.12 and 24.97 MeV, for the /sup 54/Fe(p,n)/sup 54/Co reaction at E/sub p/ = 17.20, 18.60, and 24.60 MeV, and for the /sup 56/Fe(p,n)/sup 56/Co reaction at E/sub p/ = 19.12 and 24.59 MeV. Data were taken with the LLNL Cyclograaff at 16 angles from 3.5/sup 0/ to 159.0/sup 0/. A large detector at 23.8/sup 0/ with a long neutron flight path collected high resolution spectra. This large detector also collected separate 0/sup 0/ high resolution data on the /sup 26/Mg and /sup 56/Fe(p,n) reactions at E/sub p/ = 19 MeV. Absolute differential (p,n) cross sections were extracted for 1/sup +/ states in /sup 26/Al, /sup 54/Co, and /sup 56/Co, for the 0/sup +/ isobaric analong state (IAS) in /sup 54/Co and /sup 56/Co, for a 2/sup +/ state in each residual nucleus, and for the 0.199 MeV 7/sup +/ state of /sup 54/Co. No new experimental states were identified. Only relative cross sections were extracted at 0/sup 0/. Experimental angle-integrated cross sections were obtained for all but one state. DWBA79 was used, with the G-matrix effective nucleon-nucleon interaction of Bertsch et al. (with the central triplet-odd component V/sub to/ = O) and the Livermore shell model wave functions to calculate differential (p,n) cross sections to 1/sup +/ states and to the /sup 54/Co and /sup 56/Co IAS. Normalization of the DWBA angle-integrated cross sections to measurements for the /sup 54/Co and /sup 56/Co IAS (at E/sub p/ = 24.6 MeV) yielded the renormalized V/sub tau/ = 21.4 +- 2.1 MeV. Normalization of the DWBA angle-integrated cross sections to measurements for the 24.6 MeV /sup 54/Co and /sup 56/Co 1/sup +/ states, coupled with the normalization of the wave functions to previously experimentally determined GT strength, yield the renormalized V/sub sigmatau/ = 12.3 +- 1.2 MeV. The experimental Gamow-Teller strength B(GT)/sub exp./ of the T = 1 /sup 26/Al state at 9.44 MeV was found to be 0.69; B

  10. Benchmark experiment for the cross section of the {sup 100}Mo(p,2n){sup 99m}Tc and {sup 100}Mo(p,pn){sup 99}Mo reactions

    Energy Technology Data Exchange (ETDEWEB)

    Takács, S., E-mail: stakacs@atomki.hu [Institute for Nuclear Research, Hungarian Academy of Sciences, 4026 Debrecen (Hungary); Ditrói, F. [Institute for Nuclear Research, Hungarian Academy of Sciences, 4026 Debrecen (Hungary); Aikawa, M. [Faculty of Science, Hokkaido University, Sapporo 060-0810 (Japan); Haba, H. [Nishina Center for Accelerator-Based Science, RIKEN, Wako, Saitama 351-0198 (Japan); Otuka, N. [Nuclear Data Section, IAEA, Wien A-1400 (Austria)

    2016-05-15

    As nuclear medicine community has shown an increasing interest in accelerator produced {sup 99m}Tc radionuclide, the possible alternative direct production routes for producing {sup 99m}Tc were investigated intensively. One of these accelerator production routes is based on the {sup 100}Mo(p,2n){sup 99m}Tc reaction. The cross section of this nuclear reaction was studied by several laboratories earlier but the available data-sets are not in good agreement. For large scale accelerator production of {sup 99m}Tc based on the {sup 100}Mo(p,2n){sup 99m}Tc reaction, a well-defined excitation function is required to optimise the production process effectively. One of our recent publications pointed out that most of the available experimental excitation functions for the {sup 100}Mo(p,2n){sup 99m}Tc reaction have the same general shape while their amplitudes are different. To confirm the proper amplitude of the excitation function, results of three independent experiments were presented (Takács et al., 2015). In this work we present results of a thick target count rate measurement of the E{sub γ} = 140.5 keV gamma-line from molybdenum irradiated by E{sub p} = 17.9 MeV proton beam, as an integral benchmark experiment, to prove the cross section data reported for the {sup 100}Mo(p,2n){sup 99m}Tc and {sup 100}Mo(p,pn){sup 99}Mo reactions in Takács et al. (2015).

  11. EKSEPSI PLURIUM LITIS CONSORTIUM (Studi Terhadap Putusan Pengadilan Tinggi Semarang No. 401/Pdt/2002/PT. Smg jo. Putusan Pengadilan Negeri Purwokerto No.41/Pdt.G/2000/PN.Pwt

    Directory of Open Access Journals (Sweden)

    Siti Muflichah

    2008-05-01

    Full Text Available In the civil jurisdiction, truth searched is the formal truth. This matter of course different from the criminal justice, where truth searched is material truth. Searching the formal truth, meaning that judge may not be abysmal of boundary that raised by the parties. This matter contain the congeniality, that verification process is not see at wight or content, but to wide of case scope or dispute that raised by the parties. In this case judge have the passive character. in civil jurisdiction, truth searched is a truth that relying on formal verification. The Judge decision shall contain the rule of law element, justice and benefit. For the reason judge have to careful, goodness in making draft of decision and also decision intake later. In Case No. 401/ Pdt / 2002 / PT. Smg, The Judge of High Court of middle of Java made the decision by strengthening decision of District Court of Purwokerto in case No. 41/Pdt.G/2000/PN Pwt. This Judge Decision represent an example of careless of the judge in make decision. exception of the lack of party had refused. Therefore, judge have to consider this matter in its decision. Therefore, judge have to consider this matter in its decision. This matter of course relative harm the plaintiff, because if suing is not accepted, plaintiff can improve/ repair its suing or make a lawsuit to the court newly again. But refusedly of suing make the plaintiff cannot improve/ repair its suing or make the new suing again. finally, the decision which is not careful will not fulfill the rule of law elements, justice and benefit.

  12. Highly efficient photocatalysis by BiFeO{sub 3}/{alpha}({gamma})-Fe{sub 2}O{sub 3} ferromagnetic nano p/n junctions formed by dopant-induced phase separation

    Energy Technology Data Exchange (ETDEWEB)

    Ramadan, Wegdan, E-mail: wegdan.ramadan@gmail.com [Alexandria University, Physics Department, Faculty of Science (Egypt); Shaikh, Parvez A. [National Chemical Laboratory (CSIR-NCL), Council of Scientific and Industrial Research (India); Ebrahim, Sh. [Alexandria University, Materials Science Department, Institute of Graduate Studies and Research (Egypt); Ramadan, Abdallah [Alexandria University, Physics Department, Faculty of Science (Egypt); Hannoyer, Beatrice; Jouen, Samuel; Sauvage, Xavier [Universite de Rouen, GPM, UMR 6634 CNRS (France); Ogale, Satishchandra, E-mail: sb.ogale@ncl.res.in [National Chemical Laboratory (CSIR-NCL), Council of Scientific and Industrial Research (India)

    2013-08-15

    A series of Bi{sub 1-x}Ca{sub x}FeO{sub 3} (BCFO) nanoparticles (with x = 0.0, 0.03, 0.07, 0.10, 0.15, and 0.20) have been synthesized by sol-gel reaction. X-ray diffraction patterns establish the formation of hexagonal bismuth ferrite as the prominent phase, with a small contribution of the Bi{sub 2}Fe{sub 4}O{sub 9} phase (as reported by others as well) which diminishes rapidly with the increase in Ca concentration. Interestingly, above a calcium dopant concentration of about 10 % peaks of Fe{sub 2}O{sub 3} (both {alpha} and {gamma} components) are observed with a concomitant enhancement of ferromagnetism. Small contribution of the Bi{sub 6}Ca{sub 4}O{sub 13} phase is also noted in these samples. This phase evolution is driven by dopant-induced strain energy and increasing oxygen vacancy concentration for local charge balance. Transmission electron microscopy (with elemental scanning) and Moessbauer spectroscopy techniques bring out the evolution of nanoparticle morphology (and elemental distribution) and phase configuration, respectively. Measurements of photocatalytic activity (and photo-Fenton activity with H{sub 2}O{sub 2}) reveal that Ca doping at the Bi site in BFO enhances the activity significantly in the concentration regime where BFO/{alpha}({gamma})-Fe{sub 2}O{sub 3} phases coexist in the form of a nanocomposite. The enhancement can thus be attributed to the carrier transfer between BFO and {alpha}({gamma})-Fe{sub 2}O{sub 3} across nano p/n junctions leading to enhanced carrier lifetime. Importantly, the magnetization of the nanocomposite (about 16 emu gm{sup -1} at x = 0.20) provides a convenient way to collect the photocatalyst with the help of an external magnet for reuse.

  13. A highly efficient visible-light-driven novel p-n junction Fe{sub 2}O{sub 3}/BiOI photocatalyst: Surface decoration of BiOI nanosheets with Fe{sub 2}O{sub 3} nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Mehraj, Owais; Pirzada, Bilal M.; Mir, Niyaz A.; Khan, Mohammad Zain; Sabir, Suhail, E-mail: sabirsuhail09@gmail.com

    2016-11-30

    Highlights: • BiOI/Fe{sub 2}O{sub 3}p-n heterojunctions were synthesized through an in-situ hydrolysis method under solvothermal conditions. • BiOI/Fe{sub 2}O{sub 3}p-n heterojunctions showed enhanced visible light activity than single BiOI. • BiOI/Fe{sub 2}O{sub 3}p-n heterojunctions showed improved stability than pure BiOI nanosheets. - Abstract: Novel xFe{sub 2}O{sub 3}/yBiOI composites (x/y = 0.25, 0.35, 0.45 molar ratios) with a p-n heterojunction were prepared for the first time through an in situ hydrolysis method under solvothermal conditions. The phase structure, morphology and optical properties of the composites were studied using several characterization tools including X-ray diffraction (XRD), scanning electron microscopy (SEM), high resolution transmission electron microscopy (HRTEM), selected area electron diffraction (SAED), Fourier transform infrared (FTIR), N{sub 2} adsorption-desorption isotherms (BET) and UV–vis diffuse reflectance spectroscopy (UV-DRS). The characterization results suggest square shaped nanosheets of BiOI with Fe{sub 2}O{sub 3} nanoparticles well distributed on the surface of BiOI nanosheets. The photodegradation performances of the xFe/yBi samples were investigated using aqueous solution of Rhodamine B (RhB) dye. The xFe/yBi composites displayed much higher photocatalytic efficiencies for RhB degradation than the single BiOI under visible light (λ > 400 nm). Specifically, the degradation rate of xFe/yBi samples at molar ratio of 0.35 is 4.24 times higher than single BiOI. The novel Fe{sub 2}O{sub 3}/BiOI heterojunction was found to be highly stable in cyclic experiments. Based on the results of BET, PL and DRS analysis, the enhanced photocatalytic efficiency can be mainly ascribed to the formation of stable p-n heterojunction between Fe{sub 2}O{sub 3} and BiOI, which facilitates the transfer and separation of photogenerated electron-hole pairs.

  14. PODAAC-GHVRS-2PN02

    Data.gov (United States)

    National Aeronautics and Space Administration — A global Group for High Resolution Sea Surface Temperature (GHRSST) Level 2P dataset based on retrievals from the Visible Infrared Imaging Radiometer Suite (VIIRS)....

  15. PODAAC-GHVRS-2PN01

    Data.gov (United States)

    National Aeronautics and Space Administration — A global Group for High Resolution Sea Surface Temperature (GHRSST) Level 2P dataset based on retrievals from the Visible Infrared Imaging Radiometer Suite (VIIRS)....

  16. PODAAC-GHVRS-2PN16

    Data.gov (United States)

    National Aeronautics and Space Administration — The Visible and Infrared Imager/Radiometer Suite (VIIRS) is a multi-disciplinary instrument that is being flown on the Joint Polar Satellite System (JPSS) series of...

  17. The charge plasma P-N diode

    NARCIS (Netherlands)

    Hueting, Raymond Josephus Engelbart; Rajasekharan, B.; Salm, Cora; Schmitz, Jurriaan

    2008-01-01

    A simulation study on a new rectifier concept is presented. This device basically consists of two gates with different workfunctions on top of a thin intrinsic or lowly doped silicon body. The workfunctions and layer thicknesses are chosen such that an electron plasma is formed on one side of the

  18. PODAAC-GHMTG-2PN01

    Data.gov (United States)

    National Aeronautics and Space Administration — A global Group for High Resolution Sea Surface Temperature (GHRSST) Level 2P dataset based on multi-channel sea surface temperature (SST) retrievals generated in...

  19. PODAAC-GHMTB-2PN02

    Data.gov (United States)

    National Aeronautics and Space Administration — A global Group for High Resolution Sea Surface Temperature (GHRSST) Level 2P dataset based on multi-channel sea surface temperature (SST) retrievals generated in...

  20. PODAAC-GHMTG-2PN02

    Data.gov (United States)

    National Aeronautics and Space Administration — A global Group for High Resolution Sea Surface Temperature (GHRSST) Level 2P dataset based on multi-channel sea surface temperature (SST) retrievals generated in...

  1. Multiplication in Silicon p-n Junctions

    DEFF Research Database (Denmark)

    Moll, John L.

    1965-01-01

    Multiplication values were measured in the collector junctions of silicon p-n-p and n-p-n transistors before and after bombardment by 1016 neutrons/cm2. Within experimental error there was no change either in junction fields, as deduced from capacitance measurements, or in multiplication values...

  2. Study of recombination processes for 'electron-hole' pairs in germanium irradiated by {gamma} rays from {sup 60}Co using the photovoltaic effect in P-N junctions; Etude du processus de recombinaison des paires ''electron-trou'' dans le germanium irradie par les rayons {gamma} du cobalt 60 a l'aide de l'effet photovoltaique dans les jonctions P-N

    Energy Technology Data Exchange (ETDEWEB)

    Zahedi-Mochadam, A.A. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1964-10-01

    Using the photo-voltaic effect in p-n junctions, we have studied, during bombardment, the mechanism of the recombination of 'electron-hole' pairs in the presence of structure defects produced in germanium of the N and P types by {gamma} rays from a Co{sup 60} source. At 310 K the level of the recombination centres is situated 0.25 eV above the conduction band and the capture cross-sections of the holes and of the electrons have the respective values of: {sigma}{sub p} = 4 X 10{sup -15} cm{sup 2} and {sigma}{sub n} = 3 X 10{sup -15} cm{sup 2}. The value of {sigma}{sub n} appears to be under-estimated because the number of defects in P-type samples appears to be lower than that in N-type samples. These results lead to the conclusion that the interstitials are responsible for the recombination. At 80 K it has been found that in N-type samples, a shallow level exists at O.05 eV below the conduction band with a capture cross-section for the holes of {sigma}{sub p} {>=} 10{sup -14} cm{sup 2}. We believe that in this case the recombination of charge carriers is controlled by the neighbouring 'defect-interstitial' pairs. In P-type samples at low temperature, the life-time is practically constant during irradiation. This fact is attributed to a spontaneous annealing of defects ol purely electrical origin. In the last part of the work the study of the photo-voltaic effect applied to the problem of gamma radiation dosimetry is considered. It is shown that such dosimeters, based on this principle, make it possible to measure the intensity of gamma rays over a very wide range. (author) [French] En utilisant l'effet photovoltaique dans les jonctions p-n, nous avons etudie au cours du bombardement le mecanisme de recombinaison des paires 'electron-trou' en presence des defauts de structure introduits dans le germanium de type N et de type P par les rayons gamma d'une source de Co{sup 60}. A 310 K, le niveau des centres de recombinaison se

  3. Predicting the 5-Year Risk of Biochemical Relapse After Postprostatectomy Radiation Therapy in ≥PT2, pN0 Patients With a Comprehensive Tumor Control Probability Model

    Energy Technology Data Exchange (ETDEWEB)

    Fiorino, Claudio, E-mail: fiorino.claudio@hsr.it [Department of Medical Physics, San Raffaele Scientific Institute, Milan (Italy); Broggi, Sara [Department of Medical Physics, San Raffaele Scientific Institute, Milan (Italy); Fossati, Nicola [Division of Oncology/Unit of Urology, URI, IRCCS Ospedale San Raffaele, Milan (Italy); Cozzarini, Cesare [Department of Radiotherapy, IRCCS Ospedale San Raffaele, Milan (Italy); Goldner, Gregor [Klinik für Radioonkologie, Medizinische Universität Wien, Wien (Austria); Wiegel, Thomas [Department of Radiation Oncology, University Hospital Ulm, Ulm (Germany); Hinkelbein, Wolfgang [Department of Radiation Oncology, Charité Universitats Medizin, Campus Benjamin Franklin, Berlin (Germany); Karnes, R. Jeffrey; Boorjian, Stephen A. [Department of Urology, Mayo Clinic Rochester, Rochester, Minnesota (United States); Haustermans, Karin [Department of Radiotherapy, University Hospitals Leuven, Leuven (Belgium); Joniau, Steven [Department of Urology, University Hospitals Leuven, Leuven (Belgium); Palorini, Federica [Department of Medical Physics, San Raffaele Scientific Institute, Milan (Italy); Shariat, Shahrokh [Department of Urology, Comprehensive Cancer Center, Medical University of Vienna, Vienna General Hospital, Vienna (Austria); Montorsi, Francesco [Division of Oncology/Unit of Urology, URI, IRCCS Ospedale San Raffaele, Milan (Italy); Van Poppel, Hein [Department of Urology, University Hospitals Leuven, Leuven (Belgium); Di Muzio, Nadia [Department of Radiotherapy, IRCCS Ospedale San Raffaele, Milan (Italy); Calandrino, Riccardo [Department of Medical Physics, San Raffaele Scientific Institute, Milan (Italy); Briganti, Alberto [Division of Oncology/Unit of Urology, URI, IRCCS Ospedale San Raffaele, Milan (Italy)

    2016-10-01

    Purpose: To fit the individual biochemical recurrence-free survival (bRFS) data from patients treated with postprostatectomy radiation therapy (RT) with a comprehensive tumor control probability (TCP) model. Methods and Materials: Considering pre-RT prostate-specific antigen (PSA) as a surrogate of the number of clonogens, bRFS may be expressed as a function of dose-per-fraction–dependent radiosensitivity (α{sub eff}), the number of clonogens for pre-RT PSA = 1 ng/mL (C), and the fraction of patients who relapse because of clonogens outside the treated volume (K), assumed to depend (linearly or exponentially) on pre-RT PSA and Gleason score (GS). Data from 894 node-negative, ≥pT2, pN0 hormone-naive patients treated with adjuvant (n=331) or salvage (n=563) intent were available: 5-year bRFS data were fitted grouping patients according to GS (<7:392, =7:383, >7:119). Results: The median follow-up time, pre-RT PSA, and dose were 72 months, 0.25 ng/mL, and 66.6 Gy (range 59.4-77.4 Gy), respectively. The best-fit values were 0.23 to 0.26 Gy{sup −1} and 10{sup 7} for α{sub eff} and C for the model considering a linear dependence between K and PSA. Calibration plots showed good agreement between expected and observed incidences (slope: 0.90-0.93) and moderately high discriminative power (area under the curve [AUC]: 0.68-0.69). Cross-validation showed satisfactory results (average AUCs in the training/validation groups: 0.66-0.70). The resulting dose-effect curves strongly depend on pre-RT PSA and GS. bRFS rapidly decreases with PSA: the maximum obtainable bRFS (defined as 95% of the maximum) declined by about 2.7% and 4.5% for each increment of 0.1 ng/mL for GS <7 and ≥7, respectively. Conclusions: Individual data were fitted by a TCP model, and the resulting best-fit parameters were radiobiologically consistent. The model suggests that relapses frequently result from clonogens outside the irradiated volume, supporting the choice of lymph

  4. A comparison of Gridded Quantile Mapping vs. Station Based Downscaling Approaches on Potential Hydrochemical Responses of Forested Watersheds to Climate Change Using a Dynamic Biogeochemical Model (PnET-BGC)

    Science.gov (United States)

    Pourmokhtarian, A.; Driscoll, C. T.; Campbell, J. L.; Hayhoe, K.

    2012-12-01

    Dynamic hydrochemical models are useful tools to understand and predict the interactive effects of climate change, atmospheric CO2, and atmospheric deposition on the hydrology and water quality of forested watersheds. Although application of these models for climate projections necessitates the use of climatic variables simulated by atmosphere-ocean general circulation models (AOGCMs) to determine inputs to drive model projections. Due to the coarse resolution of AOGCMs, outputs need to be downscaled to bridge the gap between coarse spatial resolution and higher resolution required for hydrochemical models. This research compares two different statistical downscaling approaches; Gridded Quantile Mapping (BCSD) and Station-based Daily Asynchronous Regression, and their effects on potential biogeochemical responses of forested watershed. In this study, we used the biogeochemical model, PnET-BGC, to assess, compare and contrast the effects of these two downscaling approaches on potential future changes in temperature, precipitation, solar radiation and atmospheric CO2 and their effects in projections of pools, concentrations, and fluxes of major elements at Hubbard Brook Experimental Forest in New Hampshire, U.S. Future emissions scenarios were developed from monthly output from three AOGCMs (HadCM3, GFDL, PCM) in conjunction with potential lower and upper bounds of projected atmospheric CO2 (550 and 970 ppm by 2099, respectively). The climate projections from both downscaling approaches indicate that over the 21st century, average air temperature will increase with simultaneous increases in annual average precipitation. The modeling results from both downscaling approaches suggest that climate change is projected to cause substantial temporal shifts in hydrologic and hydrochemistry patterns. The choice of downscaling approach had a major impact on the streamflow simulations, which was directly related to the ability of the downscaling approach to mimic observed

  5. Excitation function measurements of sup 4 sup 0 Ar(p,3n) sup 3 sup 8 K, sup 4 sup 0 Ar(p,2pn) sup 3 sup 8 Cl and sup 4 sup 0 Ar(p,2p) sup 3 sup 9 Cl reactions

    CERN Document Server

    Nagatsu, K; Suzuki, K

    1999-01-01

    For the production of sup 3 sup 8 K, excitation functions of the sup 4 sup 0 Ar(p,3n) sup 3 sup 8 K reaction and its accompanying reactions sup 4 sup 0 Ar(p,2pn) sup 3 sup 8 Cl, and sup 4 sup 0 Ar(p,2p) sup 3 sup 9 Cl were measured at the proton energy of 20.5-39.5 MeV to determine the optimum conditions of irradiation. Target cells containing argon gas were prepared using specially developed tools in an argon-replaced glove box. In the sup 4 sup 0 Ar(p,3n) sup 3 sup 8 K, sup 4 sup 0 Ar(p,2pn) sup 3 sup 8 Cl, and sup 4 sup 0 Ar(p,2p) sup 3 sup 9 Cl reactions, the maximum cross sections were 6.7+-0.7, 34+-3.3 and 11+-1.2mbarn at 37.6, 39.5 and 32.0 MeV, respectively, and the saturation thick target yields were calculated to be 560, 2200, and 1300 sup * MBq/mu A, respectively, at an incident energy of 39.5 MeV ( sup * integral yield above 21 MeV).

  6. Migratory insertion of the R2P group into a nitrogen-nitrogen bond - a novel type of rearrangement in phosphorus-nitrogen ligand chemistry. 3. The rearrangement of triphosphinohydrazide ligand -N(PPh2)-N(PPh2)2 to triphosphazenide anion {[(Ph2P-N]2PPh2}- in the coordination sphere of divalent cobalt and nickel.

    Science.gov (United States)

    Sushev, Vyacheslav V; Belina, Natalia V; Fukin, Georgy K; Kurskiy, Yuriy A; Kornev, Alexander N; Abakumov, Gleb A

    2008-04-07

    Hydrazine dihydrochloride reacts with 3 equiv of Ph2PCl in tetrahydrofuran in the presence of triethylamine to give tris(diphenylphosphino)hydrazine (1) in 70% yield. Each nitrogen atom in 1 has a trigonal-planar environment according to X-ray analysis. Thermolysis of 1 at 130 degrees C results in the formation of two products: bis(diphenylphosphino)amine and octaphenylcyclotetraphosphazene. The interaction of free ligand 1 with NiBr2 affords a simple adduct [(Ph2P)2N-NH-PPh2]NiBr2, while its anionic (hydrazide) form undergoes rearrangement in a coordination sphere of divalent cobalt and nickel involving migratory insertion of the Ph2P group into a nitrogen-nitrogen bond. The reaction of 1 with cobalt bis(trimethylsilyl)amide, [(Me3Si)2N]2Co, yields the complex of phosphazenide-type (Me3Si)2N-Co[(Ph2PN)2PPh2] (2) in 86% yield. A similar reaction of 1 with nikelocene proceeds with substitution of one Cp ring to form durable 18-electron complex CpNi[(Ph2PN)2PPh2] (3).

  7. Glenohumeral instabilitelerde pnömoartro-bilgisayarlı tomografiGlenohumeral instabilitelerde pnömoartro-

    OpenAIRE

    Yel, Mustafa; Karabacakoglu, Aydin; Karakose, Serdar; Arazi, Mehmet; Akcali, Omer

    2004-01-01

    Objectives: To determine the accuracy of x-ray, computed tomography (CT), and pneumoarthro-CT (PA-CT) in correlation with arthroscopy or arthrotomy findings in bone and soft tissue changes of traumatic anterior glenohumeral (GH) instabilities. Methods: The study included 20 patients (19 males, 1 female; mean age 23.4 years; range 17 to 41 years) who underwent surgery for recurrent shoulder dislocations. Shoulder x-ray, CT, and PA-CT examinations were performed in all patients. Bone lesions...

  8. Dispersion analysis of the Pn -Pn-1DG mixed finite element pair for atmospheric modelling

    Science.gov (United States)

    Melvin, Thomas

    2018-02-01

    Mixed finite element methods provide a generalisation of staggered grid finite difference methods with a framework to extend the method to high orders. The ability to generate a high order method is appealing for applications on the kind of quasi-uniform grids that are popular for atmospheric modelling, so that the method retains an acceptable level of accuracy even around special points in the grid. The dispersion properties of such schemes are important to study as they provide insight into the numerical adjustment to imbalance that is an important component in atmospheric modelling. This paper extends the recent analysis of the P2 - P1DG pair, that is a quadratic continuous and linear discontinuous finite element pair, to higher polynomial orders and also spectral element type pairs. In common with the previously studied element pair, and also with other schemes such as the spectral element and discontinuous Galerkin methods, increasing the polynomial order is found to provide a more accurate dispersion relation for the well resolved part of the spectrum but at the cost of a number of unphysical spectral gaps. The effects of these spectral gaps are investigated and shown to have a varying impact depending upon the width of the gap. Finally, the tensor product nature of the finite element spaces is exploited to extend the dispersion analysis into two-dimensions.

  9. Quality of Life and Economic Burden in Recessive Dystrophic Epidermolysis Bullosa.

    Science.gov (United States)

    Jeon, In Kyung; On, Hye Rang; Kim, Soo-Chan

    2016-02-01

    Patients with recessive dystrophic epidermolysis bullosa (RDEB) exhibit blisters and erosions since birth, causing pain, pruritus and various complications. RDEB affects quality of life (QoL) in physical, emotional and social aspects. Furthermore, interminable dressing changes and supportive therapies impose a significant economic burden on the patient's family. We assessed the QoL and economic burden in patients with RDEB. Sixteen patients with RDEB were surveyed to assess the QoL and economic burden. Patients answered questionnaires consisting of a visual analogue scale (VAS) on pain and pruritus, Skindex-29, Quality of Life in EB questionnaire (QOLEB), and the economic burden due to EB. Thirteen patients with RDEB completed the questionnaire. Female patients presented higher VAS, QOLEB and total Skindex-29 scores than male patients. Patients with RDEB showed severe levels of pruritus, which was more intolerable than pain. Mean VAS score on pain in RDEB was higher than in oral lichen planus and post-herpetic neuralgia. VAS score on pruritus was similar to those in chronic urticaria, atopic dermatitis, and prurigo nodularis. Compared with other dermatologic conditions, patients with RDEB were profoundly affected in all three scales of skindex-29. Mean "medical cost" in a month was $257.54 (USD) (±169.39) and mean "dressing cost" was $358.41 (USD) (±312.55), which was negatively related to patient age. RDEB had a profound impact on QoL and economic burden. Compared with other dermatologic diseases, RDEB showed severe symptoms and QoL was seriously impaired. Most patients sustained economic burdens, especially on preparing dressing materials. Younger patients experienced more economic burdens.

  10. Four Novel p.N385K, p.V36A, c.1033–1034insT and c.1417–1418delCT Mutations in the Sphingomyelin Phosphodiesterase 1 (SMPD1 Gene in Patients with Types A and B Niemann-Pick Disease (NPD

    Directory of Open Access Journals (Sweden)

    Masoumeh Dehghan Manshadi

    2015-03-01

    Full Text Available Background: Types A and B Niemann-Pick disease (NPD are autosomal-recessive lysosomal storage disorders caused by the deficient activity of acid sphingomyelinase due to mutations in the sphingomyelin phosphodiesterase 1 (SMPD1 gene. Methods: In order to determine the prevalence and distribution of SMPD1 gene mutations, the genomic DNA of 15 unrelated Iranian patients with types A and B NPD was examined using PCR, DNA sequencing and bioinformatics analysis. Results: Of 8 patients with the p.G508R mutation, 5 patients were homozygous, while the other 3 were heterozygous. One patient was heterozygous for both the p.N385K and p.G508R mutations. Another patient was heterozygous for both the p.A487V and p.G508R mutations. Two patients (one homozygous and one heterozygous showed the p.V36A mutation. One patient was homozygous for the c.1033–1034insT mutation. One patient was homozygous for the c.573delT mutation, and 1 patient was homozygous for the c.1417–1418delCT mutation. Additionally, bioinformatics analysis indicated that two new p.V36A and p.N385K mutations decreased the acid sphingomyelinase (ASM protein stability, which might be evidence to suggest the pathogenicity of these mutations. Conclusion: with detection of these new mutations, the genotypic spectrum of types A and B NPD is extended, facilitating the definition of disease-related mutations. However, more research is essential to confirm the pathogenic effect of these mutations.

  11. Legionella pnömonisini taklit eden malignite olgusu

    OpenAIRE

    Ali Karakuş; Ersin Şükrü Erden; Cenk Babayiğit; Eyüp Büyükkaya; Mehmet Mustafa Akın; Muhammet Murat Çelik; Veyis Taşın

    2013-01-01

    Legionella pneumophila is a bacterium, which can grow inwater pipe networks and climate systems. Contaminationoccurs by aspiration of infected water or aerosol inhalation.It is usually presented with fever, bradycardia, andchange in mental status, hyponatremia, elevation of liverenzymes and deterioration of renal function. The definitediagnosis is established by detection of the antigens andcultivating in the culture medium. Also, malign lung tumorscan encounter with the same clinical finding...

  12. Molecular processes from the AGB to the PN stage

    Science.gov (United States)

    García-Hernández, D. Anibal

    2012-08-01

    Many complex organic molecules and inorganic solid-state compounds have been observed in the circumstellar shell of stars (both C-rich and O-rich) in the transition phase between Asymptotic Giant Branch (AGB) stars and Planetary Nebulae (PNe). This short (~102-104 years) phase of stellar evolution represents a wonderful laboratory for astrochemistry and provides severe constraints on any model of gas-phase and solid-state chemistry. One of the major challenges of present day astrophysics and astrochemistry is to understand the formation pathways of these complex organic molecules and inorganic solid-state compounds (e.g., polycyclic aromatic hydrocarbons, fullerenes, and graphene in the case of a C-rich chemistry and oxides and crystalline silicates in O-rich environments) in space. In this review, I present an observational review of the molecular processes in the late stages of stellar evolution with a special emphasis on the first detections of fullerenes and graphene in PNe.

  13. Airborne Gravity: NGS' Gravity Data for PN01 (2014)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Airborne gravity data for California and Oregon collected in 2011 over 1 survey. This data set is part of the Gravity for the Re-definition of the American Vertical...

  14. Antimonide-based pN Terahertz Mixer Diodes

    Science.gov (United States)

    2011-06-01

    are under development including the InAs channel high electron mobility transistors , the heterojunction bipolar transistors , the resonant tunneling...spectroscopic applications . Small light-weight systems that could be hand held or carried in an airplane or satellite are highly desired. The development...not used as terahertz mixers as the junction may have a large capacitance, Cj, due to the diffusion capacitance when forward biased. The RsCj cutoff

  15. BOLIDE PHYSICAL THEORY WITH APPLICATION TO PN AND EN FIREBALLS.

    Energy Technology Data Exchange (ETDEWEB)

    ReVelle, D. O. (Douglas O.)

    2001-01-01

    Using data on 22 'precise bolides' with up to 882 individual points on their trajectories and using data on 29 'bright bolides' and on 10 artificial meteors, we tried to derive dependence of ablation and shape-density coefficients, and of luminous efficiency on various time dependent parameters. The only significant dependence we found was that on v{sub {infinity}} - v (on difference of initial and instantaneous velocities). We present the results as Eq. 3, 4 and 8, with coefficients a{sub 1}, a{sub 2}, a{sub 3}, a{sub 4}, b{sub 1}, b{sub 2}, a{sub 3}, c{sub 1}, c{sub 2}, computed for different bolide types. Also average values of ablation, and shape-density coefficients as well as average luminous efficiencies for individual bolide types are given.

  16. Hypersurfaces in Pn with 1-parameter symmetry groups II

    DEFF Research Database (Denmark)

    Plessis, Andrew du; Wall, C.T.C.

    2010-01-01

    We assume V a hypersurface of degree d in with isolated singularities and not a cone, admitting a group G of linear symmetries. In earlier work we treated the case when G is semi-simple; here we analyse the unipotent case. Our first main result lists the possible groups G. In each case we discuss...

  17. A critical test of organic P-N photovoltaic cells

    Energy Technology Data Exchange (ETDEWEB)

    Bird, G.R. [Rutgers Univ., Piscataway, NJ (United States)

    1996-09-01

    We present an urgent view of the field of organic solid state photovoltaic cells. This is a proper time to select the most promising materials from the Electrophotographic Industry, materials long tried in terms of stability, high quantum yield of charge carriers, but set apart by unusually high quantum yields at low applied fields. Our experience with the candidate dyes has covered new tests for identifiable impurities and removal of these impurities by verifiable methods. A new method of purification, reactive train sublimation, has been developed for DNT, one of the simplest of the outstanding perylene dyes, and the method seems applicable to some of the other promising perylene derivatives. It removes the offending impurity by converting it into the desired pure product. The role of water of hydration in the {open_quotes}wine cellar effect{close_quotes}, the slowly rising performance of newly made phthalocyanine containing cells has been analyzed. Under the concept of feasibility testing before a final refinement for practicality of materials and production methods, the hydration can be controlled for high level testing. At the same time, efforts go forward to eliminate the need. At least one of the best phthalocyanine components, X-H{sub 2}Pc, does not require water for peak performance. Finally, we have attacked BBIP (bis-benzimidazole perylene) one of the best and most enigmatic of the near infrared sensors. It has long been known and used as a mixture of synthetic isomers, and we hypothesize that either of these would be better than the uncontrolled mixture. A partial success in the form of isolating highly enriched crystals for an X-ray structure of the trans-molecule, is first presented here. A simple optical analysis method has been developed to follow enrichment procedures. For all of its difficult history, this material seems closest to a state of readiness for critical feasibility testing.

  18. PODAAC-GH18G-2PN02

    Data.gov (United States)

    National Aeronautics and Space Administration — A global Group for High Resolution Sea Surface Temperature (GHRSST) Level 2P dataset based on multi-channel sea surface temperature (SST) retrievals generated in...

  19. PODAAC-GH19L-2PN01

    Data.gov (United States)

    National Aeronautics and Space Administration — A regional Group for High Resolution Sea Surface Temperature (GHRSST) Level 2P dataset based on multi-channel sea surface temperature (SST) retrievals generated in...

  20. PODAAC-GH19G-2PN01

    Data.gov (United States)

    National Aeronautics and Space Administration — A global Group for High Resolution Sea Surface Temperature (GHRSST) Level 2P dataset based on multi-channel sea surface temperature (SST) retrievals generated in...

  1. PODAAC-GH17L-2PN01

    Data.gov (United States)

    National Aeronautics and Space Administration — A regional Group for High Resolution Sea Surface Temperature (GHRSST) Level 2P dataset based on multi-channel sea surface temperature (SST) retrievals generated in...

  2. PODAAC-GH18G-2PN01

    Data.gov (United States)

    National Aeronautics and Space Administration — A global Group for High Resolution Sea Surface Temperature (GHRSST) Level 2P dataset based on multi-channel sea surface temperature (SST) retrievals generated in...

  3. PODAAC-GH19G-2PN02

    Data.gov (United States)

    National Aeronautics and Space Administration — A global Group for High Resolution Sea Surface Temperature (GHRSST) Level 2P dataset based on multi-channel sea surface temperature (SST) retrievals generated in...

  4. PODAAC-GH19L-2PN02

    Data.gov (United States)

    National Aeronautics and Space Administration — A regional Group for High Resolution Sea Surface Temperature (GHRSST) Level 2P dataset based on multi-channel sea surface temperature (SST) retrievals generated in...

  5. PODAAC-GH17G-2PN01

    Data.gov (United States)

    National Aeronautics and Space Administration — Multi-Channel SST retreivals generated in real-time from NOAA-17 AVHRR Global Area Coverage data. Used operationally in Navy oceanographic analyses and forecasts.

  6. Systematic Differences in the Spectral Excitation of Pn and Lg by the Last Lop Nor Explosions and Nearby Earthquakes: Implications on the Pn/Lg Spectral Ratio Discriminant

    National Research Council Canada - National Science Library

    Xie, Jiakang

    1998-01-01

    PD and Lg spectra from the last eight Lop Nor explosions and many nearby earthquakes are collected from many broadband seismic stations, and analyzed to obtain source spectral characteristics and path Q...

  7. Adaptive Security Architecture based on EC-MQV Algorithm in Personal Network (PN)

    DEFF Research Database (Denmark)

    Mihovska, Albena D.; Prasad, Neeli R.

    2007-01-01

    Abstract — Personal Networks (PNs) have been focused on in order to support the user’s business and private activities without jeopardizing privacy and security of the users and their data. In such a network, it is necessary to produce a proper key agreement method according to the feature...... of the network. One of the features of the network is that the personal devices have deferent capabilities such as computational ability, memory size, transmission power, processing speed and implementation cost. Therefore an adaptive security mechanism should be contrived for such a network of various device...... combinations based on user’s location and device’s capability. The paper proposes new adaptive security architecture with three levels of asymmetric key agreement scheme by using context-aware security manager (CASM) based on elliptic curve cryptosystem (EC-MQV)....

  8. High-Frequency, 6.2 Angstrom pN Heterojunction Diodes

    Science.gov (United States)

    2012-01-01

    growth buffer consisted of 1000 Å unintentionally doped (UID) 0038-1101/$ - see front matter Published by Elsevier Ltd. doi:10.1016/j.sse.2011.07.010...50 Å n+ (Te: 4 1018 cm3) layer, a 250 Å n-type dop- ing grade (Te: 4 1018 to 5 1016 cm3), a 1000 Å n (Te: 5 1016 cm3) ‘‘bulk’’ layer, and a...channel heterostructure FETs for high-speed, low- power applications. IEICE Trans Electron 2008;E91-C(7):050–1057. [7] Champlain JG, Magno R, Doewon P

  9. Analysis of Three UH-60 Blackhawk Servolink Components P/N 70400-08110-061

    National Research Council Canada - National Science Library

    Pepi, Marc

    2002-01-01

    The Processing and Properties Branch of the U.S. Army Research Laboratory's (ARL) Weapons and Materials Research Directorate examined the shot-peened surfaces of three UH-60 Blackhawk utility helicopter servolinks...

  10. Poly(3-hexylthiophene)/ZnO hybrid pn junctions for microelectronics applications

    DEFF Research Database (Denmark)

    Katsia, E.; Huby, N.; Tallarida, G.

    2009-01-01

    Hybrid poly(3-hexylthiophene)/ZnO devices are investigated as rectifying heterojunctions for microelectronics applications. A low-temperature atomic layer deposition of ZnO on top of poly(3-hexylthiophene) allows the fabrication of diodes featuring a rectification ratio of nearly 105 at ±4 V...

  11. Influence of Sudden Change of Solar Mass in the PN Stage on the ...

    Indian Academy of Sciences (India)

    2016-01-27

    Jan 27, 2016 ... Author Affiliations. Yunfeng Zhu1 Caijuan Pan1 Dasheng Pan1 Hongqiang Huang1 Zhi-Fu Chen1. Department of Physics and Telecommunication Engineering of Baise University, Baise 533000, China.

  12. Development of N(2) Sensor for Determination of PN(2) in Body Tissues.

    Science.gov (United States)

    1986-08-01

    complexes to an electrode surface was ligand substitution of pyridine (py) for one of the aquo ligands of cis-Ru(II) diaquotetraammine, cis-Ru(NH3)4 (H20)2...the di- aquo species to the py complex . Next, N2 gas was bubbled through the solution and the formation of the N2 complex was followed by the decrease...displacement of one of the aquo ligands of the Ru(II) complex by a py group on the polymer coated electrode as illustrated below: + [M(L)(X 2)] s py M

  13. A neutron spectrometer for studying giant resonances with (p,n) reactions in inverse kinematics

    NARCIS (Netherlands)

    Stuhl, L.; Krasznahorkay, A.; Csatlos, M.; Algora, A.; Gulyas, J.; Kalinka, G.; Timar, J.; Kalantar-Nayestanaki, N.; Rigollet, C.; Bagchi, S.; Najafi, M. A.

    2014-01-01

    A neutron spectrometer, the European Low-Energy Neutron Spectrometer (ELENS), has been constructed to study exotic nuclei in inverse-kinematics experiments. The spectrometer, which consists of plastic scintillator bars, can be operated in the neutron energy range of 100 keV-10 MeV. The neutron

  14. Influence of Sudden Change of Solar Mass in the PN Stage on the ...

    Indian Academy of Sciences (India)

    Department of Physics and Telecommunication Engineering of Baise University,. Baise 533000, China. ∗ e-mail: pancaiiuan@163.com. Abstract. Assuming that the terminated mass is confined within the range 0.4551–0.5813M⊙ when the sun is going to evolve into a white dwarf, the velocity of the sun projecting the shell ...

  15. Effect of the pn junction engineering on Si microwire-array solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Dalmau Mallorqui, A.; Epple, F.M.; Fan, D.; Demichel, O.; Fontcuberta i Morral, A. [Laboratoire des Materiaux Semiconducteurs, Ecole Polytechnique Federale de Lausanne, 1015 Lausanne (Switzerland)

    2012-08-15

    We report on the impact of the doping concentration design on the performance of silicon microwire arrays as photovoltaic devices. We have fabricated arrays with different p- and n-doping profiles and thicknesses, obtaining mean efficiencies as high as 9.7% under AM 1.5G solar illumination. The results reveal the importance of scaling the microwire diameter with the depletion width resulting from doping concentrations. The doping of the core should be kept low in order to reduce bulk recombination. Furthermore, the thickness of the n-shell should be kept as thin as possible to limit the emitter losses. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  16. User Requirements for PN to Drive the Definition of a Valid Architecture

    DEFF Research Database (Denmark)

    Olesen, H.; Jiang, B.; Butkus, A.

    This deliverable presents a comprehensive survey of all the user scenarios, cases and case studies that have been analysed and proposed within the first year of the MAGNET project. Among the 11 cases presented in this report, 5 of them are presented in separate chapters with a catalogue of scenar...

  17. Phase transitions in liquid crystal 6O.4 (pn-hexyloxybenzylidine-p -n ...

    Indian Academy of Sciences (India)

    ) showed that the crystalline to liquid crystalline (K–SH) transition at 33.7◦C observed in the heating cycle does not revert even when the sample is cooled down to −100◦C. Hence it is inferred that a physically stable supercooled liquid ...

  18. Study of the Nuclear Antiquark Sea via p+N --> Dimuons

    Energy Technology Data Exchange (ETDEWEB)

    Moss, J.; Garvey, G.; Peng, J-C.; /Los Alamos; McCarthy, R.L.; /SUNY Stony Brook; Brown, C.N.; Cooper, W.E.; Jonckheere, A.M.; /Fermilab; Adams, M.; /Illinois U., Chicago

    1986-01-01

    We propose a precise measurement of the A dependence of the Drell-Yan process for 900 GeV protons on targets of deuterium and calcium using the E605 spectrometer. Emphasis will be placed on the kinematic region M > 4 GeV and x{sub F} > 0.2, where one is most sensitive to beam-valence-quark, target-antiquark annihilation. Such measurements will be very sensitive to the A dependence of the target sea quark distribution in the range 0.05 < x{sub 2} < 0.3, and hence provide important clues about the origin-of the EMC (European Muon Collaboration) effect, and unique information on the general issue of quark distributions in nuclear systems. Only minor modifications (liquid deuterium target, and reduced-size beam dump) of the E605 spectrometer will be required.

  19. Universally composable oblivious transfer based on a variant of lPN

    DEFF Research Database (Denmark)

    David, Bernardo Machado; Dowsley, Rafael; Nascimento, Anderson C A

    2014-01-01

    Oblivious transfer (OT) is a fundamental two-party cryptographic primitive that implies secure multiparty computation. In this paper, we introduce the first OT based on the Learning Parity with Noise (LPN) problem. More specifically, we use the LPN variant that was introduced by Alekhnovich (FOCS...... require an additional assumption related to the indistinguishability of public keys from random matrices. Our constructions are inspired by the techniques used to obtain OT based on the McEliece cryptosystem....

  20. Frequency-Dependent Characteristics of Regional Seismic Phases: Propagation of Pn in Western China

    Science.gov (United States)

    2011-01-31

    cratonic regions, such as the Indian shield or the Tarim and Sichuan basins (McNamara et al., 1997; Liang and Song, 2006; Pei et al., 2007). The...between 84°E and 86°E extending from the Ganga foreland basin , over the Lesser and Higher Himalayas, crossing the Indus-Yarlung suture and the

  1. Spectral Analyses of High-Frequency Pn, Sn Phases from Very Shallow Focus Earthquakes.

    Science.gov (United States)

    1983-09-01

    noise ratio is 18 moths from the Wake bottom hydrophones is approximately 50/1. Also shown in Figure 3 is a labeled A. Also sbon are some published...for inputs between -10.0 and +10.0 Volts, respectively. Up to 16 single ended inputs are acceptable, and the maximum throughput rate is 2.5 kHz (i.e...with a 1 kHz square-wave used to determine when the other pins can be read (i.e., are not changing states). Also output (on BNC connectors) are a 1 Hz

  2. Impact of Dopant Compensation on Graded p-n Junctions in Si Nanowires.

    Science.gov (United States)

    Amit, Iddo; Jeon, Nari; Lauhon, Lincoln J; Rosenwaks, Yossi

    2016-01-13

    The modulation between different doping species required to produce a diode in VLS-grown nanowires (NWs) yields a complex doping profile, both axially and radially, and a gradual junction at the interface. We present a detailed analysis of the dopant distribution around the junction. By combining surface potential measurements, performed by KPFM, with finite element simulations, we show that the highly doped (5 × 10(19) cm(-3)) shell surrounding the NW can screen the junction's built in voltage at shell thickness as low as 3 nm. By comparing NWs with high and low doping contrast at the junction, we show that dopant compensation dramatically decreases the electrostatic width of the junction and results in relatively low leakage currents.

  3. A waferscale Si wire solar cell using radial and bulk p-n junctions.

    Science.gov (United States)

    Jung, Jin-Young; Guo, Zhongyi; Jee, Sang-Won; Um, Han-Don; Park, Kwang-Tae; Hyun, Moon Seop; Yang, Jun Mo; Lee, Jung-Ho

    2010-11-05

    Silicon nanowires (NWs) and microwires (MWs) are cost-effectively integrated on a 4-inch wafer using metal-assisted electroless etching for solar cell applications. MWs are periodically positioned using low-level optical patterning in between a dense array of NWs. A spin-on-doping technique is found to be effective for the formation of heavily doped, thin n-type shells of MWs in which the radial doping profile is easily delineated by low voltage scanning electron microscopy. Controlled tapering of the NWs results in additional optical enhancement via optimization of the tradeoff between increased light trapping (by a graded-refractive-index) and increased reflectance (by decreasing areal density of NWs). Compared to single NW (or MW) arrayed cells, the co-integrated solar cells demonstrate improved photovoltaic characteristics, i.e. a short circuit current of 20.59 mA cm(-2) and a cell conversion efficiency of ∼ 7.19% at AM 1.5G illumination.

  4. Finite mobility effects on the radiative efficiency limit of pn-junction solar cells

    OpenAIRE

    Mattheis, J.; Werner, J.H.; Rau, U.

    2008-01-01

    The maximum power conversion efficiency of a solar cell as defined by the Shockley-Queisser (SQ) radiative recombination limit relies on the assumption that the collection probability for all photogenerated electron/hole pairs is unity. This assumption implies a virtually infinite mobility mu(n) of the photogenerated charge carriers. In order to compute the radiative efficiency limit with finite mobilities, we solve the continuity equation for minority carrier transport including an additiona...

  5. Finite mobility effects on the radiative efficiency limit of pn -junction solar cells

    Science.gov (United States)

    Mattheis, Julian; Werner, Jürgen H.; Rau, Uwe

    2008-02-01

    The maximum power conversion efficiency of a solar cell as defined by the Shockley-Queisser (SQ) radiative recombination limit relies on the assumption that the collection probability for all photogenerated electron/hole pairs is unity. This assumption implies a virtually infinite mobility μn of the photogenerated charge carriers. In order to compute the radiative efficiency limit with finite mobilities, we solve the continuity equation for minority carrier transport including an additional photon recycling term that accounts for emission of photons by radiative recombination and their subsequent reabsorption. This approach quantitatively connects the SQ approach with the classical diode theory. Even when assuming radiative recombination as the only loss mechanism, the maximum efficiency achievable within our model is reduced drastically when μn drops below a critical value. This critical value depends on the absorption coefficient, the doping density of the absorber material, as well as on the thickness and the light trapping scheme of the solar cell. Thus, these material and device parameters gain a fundamental importance as soon as finite carrier mobility is considered. Our theory yields a criterion that has to be fulfilled by any photovoltaic material in order to guarantee charge separation even in an otherwise most ideal case. Exemplary application of our model to three real photovoltaic materials, crystalline silicon (c-Si) , amorphous silicon (a-Si:H) , as well as Cu(In,Ga)Se2 (CIGS), shows that mobilities of c-Si and CIGS are three, respectively, 1 order of magnitude above this critical limit whereas the effective hole mobilities in a-Si:H are scattered around the critical value. A comparison between solar cells and light-emitting diodes with finite mobility and finite nonradiative lifetime reveals that materials for these complementary devices have to fulfill different requirements.

  6. 2.5PN kick from black-hole binaries in circular orbit: Nonspinning case

    CERN Document Server

    Mishra, Chandra Kant; Iyer, Bala R

    2013-01-01

    Using the Multipolar post-Minskowskian formalism, we compute the linear momentum flux from black-hole binaries in circular orbits and having no spins. The total linear momentum flux contains various types of instantaneous (which are functions of the retarded time) and hereditary (which depends on the dynamics of the binary in the past) terms both of which are analytically computed. In addition to the inspiral contribution, we use a simple model of plunge to compute the kick or recoil accumulated during this phase.

  7. Pronounced Effect of pn-Junction Dimensionality on Tunnel Switch Threshold Shape

    OpenAIRE

    Agarwal, Sapan; Yablonovitch, Eli

    2011-01-01

    Designing tunneling junctions with abrupt on-off characteristics and high current densities is critical for many different devices including backward diodes and tunneling field effect transistors (TFETs). It is possible to get a sharp, high conductance on/off transition by exploiting the sharp step in the density of states at band edges. The nature of the density of states, is strongly dependent on quantum dimensionality. To know the current/voltage curve requires us to specify both the n-sid...

  8. Medical Device Plug-and-Play (MD PnP) Interoperability Standardization Program Development

    Science.gov (United States)

    2009-08-01

    the timing of the image could be automatically syn- chronized with respiration , so that the ventilator need not be stopped. This seems like a simple...assessment (prior to starting invasive clinical procedures). • Support of remote- ICU surveillance and quality improvements. • “Plug-and-play...Nahapetian, H. Noshadi, M. Sarrafzadeh, W. Kaiser 5:00 – 5:15pm Flexible RFID Location System Based on Artificial Neural Networks for Medical Care

  9. Negative differential resistance and rectifying performance induced by doped graphene nanoribbons p-n device

    Science.gov (United States)

    Zhou, Yuhong; Qiu, Nianxiang; Li, Runwei; Guo, Zhansheng; Zhang, Jian; Fang, Junfeng; Huang, Aisheng; He, Jian; Zha, Xianhu; Luo, Kan; Yin, Jingshuo; Li, Qiuwu; Bai, Xiaojing; Huang, Qing; Du, Shiyu

    2016-03-01

    Employing nonequilibrium Green's Functions in combination with density functional theory, the electronic transport properties of armchair graphene nanoribbon (GNR) devices with various widths are investigated in this work. In the adopted model, two semi-infinite graphene electrodes are periodically doped with boron or nitrogen atoms. Our calculations reveal that these devices have a striking nonlinear feature and show notable negative differential resistance (NDR). The results also indicate the diode-like properties are reserved and the rectification ratios are high. It is found the electronic transport properties are strongly dependent on the width of doped nanoribbons and the positions of dopants and three distinct families are elucidated for the current armchair GNR devices. The NDR as well as rectifying properties can be well explained by the variation of transmission spectra and the relative shift of discrete energy states with applied bias voltage. These findings suggest that the doped armchair GNR is a promising candidate for the next generation nanoscale device.

  10. Cooling System for a Frame-Store PN-CCD Detector for Low Background Application

    CERN Document Server

    Pereira, H; Santos Silva, P; Kuster, M; Lang, P

    2012-01-01

    The astroparticle physics experiment CERN Axion Solar Telescope (CAST) aims to detect hypothetical axions or axion-like particles produced in the Sun by the Primakoff process. A Large Hadron Collider (LHC) prototype superconducting dipole magnet provides a 9 T transverse magnetic field for the conversion of axions into detectable X-ray photons. These photons are detected with an X-ray telescope and a novel type of frame-store CCD detector built from radio-pure materials, installed in the optics focal plane. A novel type of cooling system has been designed and built based on krypton-filled cryogenic heat pipes, made out of oxygen-free radiopure copper, and a Stirling cryocooler as cold source. The heat pipes provide an efficient thermal coupling between the cryocooler and the CCD which is kept at stable temperatures between 150 and 230 K within an accuracy of 0.1 K. A graded-Z radiation shield, also serving as a gas cold-trap operated at 120 K, is implemented to reduce the surface contamination of the CCD wind...

  11. Approximation of Mixed-Type Functional Equations in Menger PN-Spaces

    Directory of Open Access Journals (Sweden)

    M. Eshaghi Gordji

    2012-01-01

    Full Text Available Let X and Y be vector spaces. We show that a function f:X→Y with f(0=0 satisfies Δf(x1,…,xn=0 for all x1,…,xn∈X, if and only if there exist functions C:X×X×X→Y, B:X×X→Y and A:X→Y such that f(x=C(x,x,x+B(x,x+A(x for all x∈X, where the function C is symmetric for each fixed one variable and is additive for fixed two variables, B is symmetric bi-additive, A is additive and Δf(x1,…,xn=∑k=2n(∑i1=2k∑i2=i1+1k+1⋯∑in-k+1=in-k+1nf(∑i=1,i≠i1,…,in-k+1nxi-∑r=1n-k+1xir+f(∑i=1nxi-2n-2∑i=2n(f(x1+xi+f(x1-xi+2n-1(n-2f(x1 (n∈N, n≥3 for all x1,…,xn∈X. Furthermore, we solve the stability problem for a given function f satisfying Δf(x1,…,xn=0, in the Menger probabilistic normed spaces.

  12. p-n junction theory in view of excess majority carriers

    Science.gov (United States)

    Yang, Jianhong; Zhang, Yang; Chen, Wenjie; Liu, Guipeng

    2017-10-01

    The classical p\\text-n junction theory is reconstructed in view of “excess majority carriers”. The effects of excess majority carriers, in addition to the excess minority carriers, are described analytically and integrated into the theory. The quantity and distribution of excess majority carriers are presented, which give rise to an “accompanying electric field” and guarantee the space-charge neutrality of each side of the junction. The accompanying electric field is figured out analytically, and the contributions of majority carriers are clarified quantitatively, which enables the current continuity in either side of the junction. Furthermore, at any position in the quasi-neutral region, the various current components are solved in closed form and the net current is obtained in a straightforward way. The reconstructed theory provides a more thorough understanding of p\\text-n junction operation with physical conciseness.

  13. Design and Simulation of InGaN p-n Junction Solar Cell

    Directory of Open Access Journals (Sweden)

    A. Mesrane

    2015-01-01

    Full Text Available The tunability of the InGaN band gap energy over a wide range provides a good spectral match to sunlight, making it a suitable material for photovoltaic solar cells. The main objective of this work is to design and simulate the optimal InGaN single-junction solar cell. For more accurate results and best configuration, the optical properties and the physical models such as the Fermi-Dirac statistics, Auger and Shockley-Read-Hall recombination, and the doping and temperature-dependent mobility model were taken into account in simulations. The single-junction In0.622Ga0.378N (Eg = 1.39 eV solar cell is the optimal structure found. It exhibits, under normalized conditions (AM1.5G, 0.1 W/cm2, and 300 K, the following electrical parameters: Jsc=32.6791 mA/cm2, Voc=0.94091 volts, FF = 86.2343%, and η=26.5056%. It was noticed that the minority carrier lifetime and the surface recombination velocity have an important effect on the solar cell performance. Furthermore, the investigation results show that the In0.622Ga0.378N solar cell efficiency was inversely proportional with the temperature.

  14. Spectator tagging in quasi-free pn-reactions on deuterium at PROMICE/WASA, CELSIUS

    Energy Technology Data Exchange (ETDEWEB)

    Bilger, R.; Brodowski, W.; Calen, H.; Clement, H.; Dunin, V.; Dyring, J.; Ekstroem, C.; Fransson, K.; Greiff, J.; Gustafsson, L.; Haeggstroem, S.; Hoeistad, B.; Johanson, J.; Johansson, A.; Johansson, T.; Khoukaz, A.; Kilian, K.; Koch, I.; Kullander, S.; Kupsc, A.; Marciniewski, P.; Morosov, B.; Neubauer, T.; Oelert, W; Ruber, R.; Shwartz, B.; Stepaniak, J.; Sukhanov, A.; Sundberg, P.; Turowiecki, A.; Wagner, G.; Wilhelmi, Z.; Wilkin, C.; Zabierowski, J.; Zernov, A.; Zlomanczuk, J

    2000-01-31

    A set of silicon detectors has been added to the PROMICE/WASA (P/W) experiment at CELSIUS. These detectors have been used for spectator-proton tagging in proton deuteron collisions to investigate proton-neutron reactions at intermediate energies. The performance of the setup has been tested by measuring the pd {yields} d{pi}{sup o}p{sub spectator} reaction.

  15. Spectator tagging in quasi-free pn-reactions on deuterium at PROMICE/WASA, CELSIUS

    Science.gov (United States)

    Bilger, R.; Brodowski, W.; Calen, H.; Clement, H.; Dunin, V.; Dyring, J.; Ekström, C.; Fransson, K.; Greiff, J.; Gustafsson, L.; Häggström, S.; Höistad, B.; Johanson, J.; Johansson, A.; Johansson, T.; Khoukaz, A.; Kilian, K.; Koch, I.; Kullander, S.; Kupsc, A.; Marciniewski, P.; Morosov, B.; Neubauer, T.; Oelert, W.; Ruber, R.; Shwartz, B.; Stepaniak, J.; Sukhanov, A.; Sukhanov, A.; Sundberg, P.; Turowiecki, A.; Wagner, G.; Wilhelmi, Z.; Wilkin, C.; Zabierowski, J.; Zernov, A.; Zlomanczuk, J.

    2000-01-01

    A set of silicon detectors has been added to the PROMICE/WASA (P/W) experiment at CELSIUS. These detectors have been used for spectator-proton tagging in proton deuteron collisions to investigate proton-neutron reactions at intermediate energies. The performance of the setup has been tested by measuring the pd -> dπopspectator reaction

  16. Spectator tagging in quasi-free pn-reactions on deuterium at PROMICE/WASA, CELSIUS

    CERN Document Server

    Bilger, R; Calén, H; Clement, H; Dunin, V; Dyring, J; Ekström, C; Fransson, K; Greiff, J; Gustafsson, L; Häggström, S; Hoeistad, B; Johanson, J; Johansson, A; Johansson, T; Khoukaz, A; Kilian, K; Koch, I; Kullander, Sven; Kupsc, A; Marciniewski, P; Morosov, B; Neubauer, T; Oelert, W; Ruber, Roger J M Y; Shwartz, B A; Stepaniak, J; Sukhanov, A; Sukhanov, A; Sundberg, P; Turowiecki, A; Wagner, G; Wilhelmi, Z; Wilkin, C; Zabierowski, J; Zernov, A; Zlomanczuk, Yu

    2000-01-01

    A set of silicon detectors has been added to the PROMICE/WASA (P/W) experiment at CELSIUS. These detectors have been used for spectator-proton tagging in proton deuteron collisions to investigate proton-neutron reactions at intermediate energies. The performance of the setup has been tested by measuring the pd -> d pi sup o p sub s sub p sub e sub c sub t sub a sub t sub o sub r reaction

  17. pn karimi'*, sm. maru', jm bururia', kam kuria' and pa odhiamboz

    African Journals Online (AJOL)

    The organism is a cause of many diseases such as skin infections, conjunctivitis, septicemia, endocarditis, osteomyelitis, pneumonia, mastitis, enteritis, food poisoning, toxic shock syndrome and scalded skin symdrome [2]. Nasal carriage of S. aureus has been identified as the most important risk factor for the acquisition of ...

  18. Conjunctivitis and pterygium associated with the American Indian type of polymorphous light eruption.

    Science.gov (United States)

    Fletcher, D C; Romanchuk, K G; Lane, P R

    1988-02-01

    We describe three patients with the American Indian type of polymorphous light eruption (actinic prurigo), two Cree Indian sisters and a Cree Indian boy, who had eye symptoms similar to those seen in limbal-type vernal catarrh.

  19. The binuclear dual emitter [Br(CO)3Re(PN)(NP)Re(CO)3Br] (PN): 3-chloro-6-(4-diphenylphosphinyl)butoxypyridazine, a new bridging P,N-bidentate ligand resulting from the ring opening of tetrahydrofuran.

    Science.gov (United States)

    Saldías, Marianela; Manzur, Jorge; Palacios, Rodrigo E; Gómez, María L; Fuente, Julio De La; Günther, Germán; Pizarro, Nancy; Vega, Andrés

    2017-01-31

    Lithium diphenylphosphide unexpectedly provokes the ring-opening of tetrahydrofuran (THF) and by reaction with 3,6-dichloropyridazine leads to the formation of the ligand 3-chloro-6-(4-diphenylphosphinyl)butoxypyridazine (P⋯N), which was isolated. The reaction of this ligand with the (Re(CO)3(THF)Br)2 dimer yields the novel complex [Br(CO)3Re(μ-3-chloro-6-(4-diphenylphosphinyl)butoxypyridazine)2Re(CO)3Br] (BrRe(P⋯N)(N⋯P)ReBr), which was crystallized in the form of a chloroform solvate, (C46H40Br2Cl2N4O8P2Re2)·(CHCl3). The monoclinic crystal (P21/n) displays a bimetallic cage structure with a symmetry inversion centre in the middle of the rhenium to rhenium line. The molecule shows two oxidation signals occurring at +1.50 V and +1.76 V which were assigned to the Re(I)/Re(II) and Re(II)/Re(III) metal-centered couples, respectively, while signals observed at -1.38 V and -1.68 V were assigned to ligand centered reductions. Experimental and DFT/TDDFT results indicate that the UV-Vis absorption maximum of BrRe(P⋯N)(N⋯P)ReBr occurring near 380 nm displays a metal to ligand charge transfer (MLCT) character, which is consistent with CV results. Upon excitation at this wavelength, a weak emission (Φem P⋯N ligand's long carbon chain. Measurements in a frozen solvent at 77 K, where vibrational deactivation is hindered, show intense emission associated with the (3)MLCT state. These results demonstrate that BrRe(P⋯N)(N⋯P)ReBr preserves the dual emitting nature previously reported for the mononuclear complex RePNBr, with emission associated with and states.

  20. Component-Level Prognostics Health Management Framework for Passive Components - Advanced Reactor Technology Milestone: M2AT-15PN2301043

    Energy Technology Data Exchange (ETDEWEB)

    Ramuhalli, Pradeep; Roy, Surajit; Hirt, Evelyn H.; Prowant, Matthew S.; Pitman, Stan G.; Tucker, Joseph C.; Dib, Gerges; Pardini, Allan F.

    2015-06-19

    This report describes research results to date in support of the integration and demonstration of diagnostics technologies for prototypical advanced reactor passive components (to establish condition indices for monitoring) with model-based prognostics methods. Achieving this objective will necessitate addressing several of the research gaps and technical needs described in previous technical reports in this series.

  1. Ultraviolet photodetector using pn junction formed by transferrable hollow n-TiO2 nano-spheres monolayer.

    Science.gov (United States)

    Yang, Taeyoung; Park, Seong-Jin; Kim, Taek Gon; Shin, Dong Su; Suh, Kyung-do; Park, Jinsub

    2017-12-11

    We report an ultraviolet (UV) photodetector with a universally transferable monolayer film with ordered hollow TiO2 spheres on p-GaN. After forming a TiO2 monolayer film by unidirectional rubbing of hollow TiO2 spheres on a polydimethylsiloxane (PDMS) supporting plate, we used a 5% polyvinyl alcohol (PVA) aqueous solution to transfer the film onto the target substrate. The PVA/TiO2 monolayer film was detached from the PDMS film and transferred to the p-GaN/Al2O3 substrate. To investigate the effects of crystallized phases of the TiO2 hollow spheres, anatase and rutile TiO2 sphere monolayers prepared by combining template synthesis and thermal treatment. The responsiveness of the UV photodetectors using anatase and rutile hollow n-TiO2 monolayer/p-GaN was 0.203 A/W at 312 nm and 0.093 A/W at 327 nm, respectively.

  2. Prototypic Enhanced Risk Monitor Framework and Evaluation - Advanced Reactor Technology Milestone: M3AT-15PN2301054

    Energy Technology Data Exchange (ETDEWEB)

    Ramuhalli, Pradeep [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Hirt, Evelyn H. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Veeramany, Arun [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Bonebrake, Christopher A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Ivans, William J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Coles, Garill A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Coble, Jamie B. [Univ. of Tennessee, Knoxville, TN (United States); Liu, X. [Univ. of Tennessee, Knoxville, TN (United States); Wootan, David W. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Mitchell, Mark R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Brass, Mary F. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2015-09-24

    This research report summaries the development and evaluation of a prototypic enhanced risk monitor (ERM) methodology (framework) that includes alternative risk metrics and uncertainty analysis. This updated ERM methodology accounts for uncertainty in the equipment condition assessment (ECA), the prognostic result, and the probabilistic risk assessment (PRA) model. It is anticipated that the ability to characterize uncertainty in the estimated risk and update the risk estimates in real time based on equipment condition assessment (ECA) will provide a mechanism for optimizing plant performance while staying within specified safety margins. These results (based on impacting active component O&M using real-time equipment condition information) are a step towards ERMs that, if integrated with AR supervisory plant control systems, can help control O&M costs and improve affordability of advanced reactors.

  3. MOVPE growth of high optical quality InGaPN layers on GaAs (001) substrates

    Energy Technology Data Exchange (ETDEWEB)

    Kaewket, Dares; Sanorpim, Sakuntam; Tungasmita, Sukkaneste [Department of Physics, Faculty of Science, Chulalongkorn University, Phayathai Rd., Bangkok 10330 (Thailand); Katayama, Ryuji [Department of Advanced Materials Science, The University of Tokyo, 5-1-5 Kashiwa, Chiba 277-8561 (Japan); Institute for Materials Research (IMR), Tohoku University, Sendai 980-8577 (Japan); Onabe, Kentaro [Department of Advanced Materials Science, The University of Tokyo, 5-1-5 Kashiwa, Chiba 277-8561 (Japan)

    2010-07-15

    Highly luminescent In{sub 0.528}Ga{sub 0.472}P{sub 1-y}N{sub y} layers (y =0-0.027) were grown on GaAs (001) substrates by metalorganic vapor phase epitaxy. The dependence of photoluminescence (PL) properties on the N content in In{sub 0.528}Ga{sub 0.472}P{sub 1-y}N{sub y} layers was investigated. Near-band edge emissions were obviously observed up to room temperature. With increasing temperature, the PL peak energy exhibits an inverted S-shape, which explained by the strong localization of carriers at low-temperatures, while the band-to-band transition becomes dominant at higher temperatures. With incorporation of N into In{sub 0.528}Ga{sub 0.472}P, the bandgap at 10 K is red-shifted as large as 110 meV for the highest N-containing layer (y =0.027), indicating a large bandgap bowing. Further, the temperature dependence of the bandgap energy becomes significantly weak with increasing N content. Our results suggest that the density of states around the band edge of In{sub 0.528}Ga{sub 0.472}P{sub 1-y}N{sub y} is modified from that of In{sub 0.528}Ga{sub 0.472}P due to the localized states possibly induced by the presence of N. (copyright 2010 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  4. Flexible substrate compatible solution processed P-N heterojunction diodes with indium-gallium-zinc oxide and copper oxide

    Energy Technology Data Exchange (ETDEWEB)

    Choudhary, Ishan; Deepak, E-mail: saboo@iitk.ac.in

    2017-04-15

    Highlights: • Both n and p-type semiconductors are solution processed. • Temperature compatibility with flexible substrates such as polyimide. • Compatibility of p-type film (CuO) on n-type film (IZO). • Diode with rectification ratio of 10{sup 4} and operating voltage <1.5 V. • Construction of band alignment using XPS. - Abstract: Printed electronics on flexible substrates requires low temperature and solution processed active inks. With n-type indium-gallium-zinc oxide (IGZO) based electronics maturing for thin film transistor (TFT), we here demonstrate its heterojunction diode with p-copper oxide, prepared by sol-gel method and processed at temperatures compatible with polyimide substrates. The phase obtained for copper oxide is CuO. When coated on n-type oxide, it is prone to develop morphological features, which are minimized by annealing treatment. Diodes of p-CuO films with IGZO are of poor quality due to its high resistivity while, conducting indium-zinc oxide (IZO) films yielded good diode with rectification ratio of 10{sup 4} and operating voltage <1.5 V. A detailed measurement at the interface by X-ray photoelectron spectroscopy and optical absorption ascertained the band alignment to be of staggered type. Consistently, the current in the diode is established to be due to electrons tunnelling from n-IZO to p-CuO.

  5. Çocukluk çağı pnömonilerinde Mycoplazma pneumoniae'nin rolü

    OpenAIRE

    ÜNLÜTÜRK, Özlem Arslan; İNALHAN, Meral; TEMEL, Özlem; ORAL, Müjgan; ÜNLÜTÜRK, Hasan; SİPAHİER, Neslihan; İnan, Savaş

    2002-01-01

    The role of mycoplasma pneumoniae in childhood pneumoniaes Mycoplasma Pneumoniae is a major cause of respira-tory infection in school -aged children and young adults.Clinically significant disease is unusual before the age of 3 to 4 y ear,the peak incidence occurs from 5 tol5 years. Mycoplasma illnesses are mild and hospitalisation is infrequent. In order to evaluate the incidence of Mycoplasma Pneumoniae pneumonia in children we evaluated the Mycoplasma IgM antibody in 246 pédiatrie patient ...

  6. Luminescent bis-cyclometallated iridium(III) complexes containing phosphine-based ligands: Influence of the P^N bridge

    OpenAIRE

    Aranda, Braulio; Aguirre, Pedro; Moya, Sergio; Bonneau, Mickaële; Gareth Williams, J. A.; Toupet, Loïc; Escadeillas, Muriel; Le Bozec, Hubert; Guerchais, Veronique

    2014-01-01

    The crystal structures of 1, 2 and 3 have been deposited at the Cambridge Crystallographic Data Centre and allocated the deposition numbers CCDC-938912, CCDC-907692, and CCDC-912857, respectively. These data can be obtained free of charge via http://www.ccdc.cam.ac.uk/conts/retrieving.html, or from the Cambridge Crystallographic Data Centre, 12 Union Road, Cambridge CB2 1EZ, UK; fax: (+44) 1223-336-033; or e-mail: .; International audience; Three cationic bis-cyclometall...

  7. Predicting Persistence in Practical Nursing and Success on the NCLEX-PN: Examining Demographic, Non-Academic, and Academic Variables

    Science.gov (United States)

    Davis, Alicia Debra

    2015-01-01

    The United States is now in the midst of a major nursing shortage that is predicted to get worse over the next ten years (Kurzen, 2005). The Health Resources and Services Administration reports that all 50 states will suffer from a nursing shortage by 2020 (U.S. Department of Health and Human Services, 2004). This means that there will be a…

  8. pn-CCDs in a Low-Background Environment: Detector Background of the CAST X-ray Telescope

    CERN Document Server

    Kuster, M.; Rodriquez, A.; Kotthaus, R.; Brauninger, H.; Franz, J.; Friedrich, P.; Hartmann, R.; Kang, D.; Lutz, G.; Struder, L.

    2005-01-01

    The CAST experiment at CERN (European Organization of Nuclear Research) searches for axions from the sun. The axion is a pseudoscalar particle that was motivated by theory thirty years ago, with the intention to solve the strong CP problem. Together with the neutralino, the axion is one of the most promising dark matter candidates. The CAST experiment has been taking data during the last two years, setting an upper limit on the coupling of axions to photons more restrictive than from any other solar axion search in the mass range below 0.1 eV. In 2005 CAST will enter a new experimental phase extending the sensitivity of the experiment to higher axion masses. The CAST experiment strongly profits from technology developed for high energy physics and for X-ray astronomy: A superconducting prototype LHC magnet is used to convert potential axions to detectable X-rays in the 1-10 keV range via the inverse Primakoff effect. The most sensitive detector system of CAST is a spin-off from space technology, a Wolter I ty...

  9. Defect characterization of proton irradiated GaAs pn-junction diodes with layers of InAs quantum dots

    Energy Technology Data Exchange (ETDEWEB)

    Sato, Shin-ichiro, E-mail: sato.shinichiro@jaea.go.jp [Takasaki Advanced Radiation Research Institute, National Institutes for Quantum and Radiological Science and Technology, Takasaki 370-1292 (Japan); Optoelectronics and Radiation Effects Branch, U.S. Naval Research Laboratory, Washington, DC 20375 (United States); Schmieder, Kenneth J.; Warner, Jeffrey H.; Walters, Robert J. [Optoelectronics and Radiation Effects Branch, U.S. Naval Research Laboratory, Washington, DC 20375 (United States); Hubbard, Seth M.; Forbes, David V. [NanoPower Research Labs, Rochester Institute of Technology, Rochester, New York 14623 (United States); Ohshima, Takeshi [Takasaki Advanced Radiation Research Institute, National Institutes for Quantum and Radiological Science and Technology, Takasaki 370-1292 (Japan)

    2016-05-14

    In order to expand the technology of III-V semiconductor devices with quantum structures to both terrestrial and space use, radiation induced defects as well as native defects generated in the quantum structures should be clarified. Electrically active defects in GaAs p{sup +}n diodes with embedded ten layers of InAs quantum dots (QDs) are investigated using Deep Level Transient Fourier Spectroscopy. Both majority carrier (electron) and minority carrier (hole) traps are characterized. In the devices of this study, GaP layers are embedded in between the QD layers to offset the compressive stress introduced during growth of InAs QDs. Devices are irradiated with high energy protons for three different fluences at room temperature in order to characterize radiation induced defects. Seven majority electron traps and one minority hole trap are found after proton irradiation. It is shown that four electron traps induced by proton irradiation increase in proportion to the fluence, whereas the EL2 trap, which appears before irradiation, is not affected by irradiation. These defects correspond to electron traps previously identified in GaAs. In addition, a 0.53 eV electron trap and a 0.14 eV hole trap are found in the QD layers before proton irradiation. It is shown that these native traps are also unaffected by irradiation. The nature of the 0.14 eV hole trap is thought to be Ga-vacancies in the GaP strain balancing layers.

  10. Identifying Galactic halo PN candidates in the imaging surveys: J-PLUS/S-PLUS and J-PAS

    Science.gov (United States)

    Gutiérrez-Soto, L.; Gonçalves, D. R.; Akras, S.; Cortesi, A.; Ederoclite, T.; Aparício-Villegas, T.; Borges-Fernandes, M.; Daflon, S.; Pereira, C. B.; Mendes de Oliveira, C.; Viironen, K.; J-PAS Collaboration

    2017-07-01

    Halo planetary nebulae (HPNe) are able to reveal important information about stellar and chemical evolution in galaxies. Their characteristic low continuum and strong emission lines make them good objects to be searched by multi-filter imaging surveys. Given that only 14 HPNe are known in the Galaxy, we are exploring colour-colour diagrams to search for these sources in Javalambre/Southern Photometric Local Universe Survey (J-PLUS/S-PLUS) and the Javalambre-Physics of the Accelerating Universe Astrophysical Survey (J-PAS). They are narrow- and broad-band imaging cosmological surveys, with 12 and 54 filters, respectively. The J-PAS survey will be able to observe 85002 of Northern sky, it will detect sources up to magnitude mAB˜23. In the case of the J-PLUS survey the limit magnitudes is around mAB˜21.5. The S-PLUS survey will observe more than 60002 and it will map the Southern sky. Other optical emission lines sources, such as Galactic and extragalactic symbiotic stars (SySts), cataclysmic variables (CVs), QSOs at different redshifts, star-forming galaxies (SFGs), extragalactic H II regions and supernova remnants (SNR) can mimic PNe. Therefore, we explore different colour-colour diagrams in order to highlight those that can better identify HPN candidates, separating them from these other objects.

  11. Reverse current of variable-gap p-n structure with nonmonotonous coordinate dependence of forbidden band gap

    CERN Document Server

    Sokolovskij, B S

    2001-01-01

    Peculiarities of reverse current of variable-gap p-n-structure in which forbidden band gap linearly enlarges with increasing the distance from structure metallurgical edge are analyzed theoretically. It is shown that by means of the variable-gap capability one can significantly reduce the reverse current related to the carrier thermal generation in base regions and at Ohmic contacts. The possibility of formation of reverse branch of the voltage-current characteristic of a portion with negative differential resistance in the case of large forbidden band gap gradients is predicted

  12. A 3D Tomographic Model of South Central Asia Based on Pn Travel Times from GT Events

    Science.gov (United States)

    2008-09-01

    throughout most of the region, with the exception of low-velocity regions near the Tarim Basin and in the southeast part of China. Both the positive and...underneath the Tibetan Plateau, then being sharply truncated by low-velocity material at the Tarim Basin for slices that cross that basin farther to the

  13. Characterization of germanium/silicon p-n junction fabricated by low temperature direct wafer bonding and layer exfoliation

    Science.gov (United States)

    Gity, Farzan; Yeol Byun, Ki; Lee, Ko-Hsin; Cherkaoui, Karim; Hayes, John M.; Morrison, Alan P.; Colinge, Cindy; Corbett, Brian

    2012-02-01

    The current transport across a p-Ge/n-Si diode structure obtained by direct wafer bonding and layer exfoliation is analysed. A low temperature anneal at 400 °C for 30 min was used to improve the forward characteristics of the diode with the on/off ratio at -1 V being >8000. Post anneal, the transport mechanism has a strong tunnelling component. This fabrication technique using a low thermal budget (T ≤ 400 °C) is an attractive option for heterogeneous integration.

  14. Measurement of the 3He(e,e'p)pn Reaction at High Missing Energies and Momenta

    Energy Technology Data Exchange (ETDEWEB)

    Benmokhtar, Fatiha [Rutgers Univ., New Brunswick, NJ (United States)

    2004-10-01

    We investigate the structure of 3He through the measurement of quasielastic 3He(e,e'). The measurements use the high duty factor electron beam and the high-precision two-spectrometer system in Hall A of the Thomas Jefferson National Accelerator Facility (TJNAF). The measurements were performed in perpendicular kinematics at fixed momentum and energy transfer by the electron, |$\\vec{q}$|= 1.5 GeV/c and omega = 837 MeV, respectively. A description of the reaction in the plane wave impulse approximation is presented. The experimental equipment is described in detail. For the measurements, the kinematics of the experiment are given. The procedures to remove backgrounds and perform radiative corrections, are also discussed in detail. The detailed method of performing radiative corrections in particular is novel to this work. Finally, the resulting cross sections, distorted spectral functions, and asymmetry ATL are presented, and the physics implications are discussed. We extracted cross sections and distorted spectral functions up to high missing momentum, pm up to 1 GeV/c, and up to high missing energies, Em up to 140 MeV, the pion production threshold. The experimental data are much higher in statistics and much more extensive in kinematic coverage than any previous measurement. Theoretical predictions are in good agreement with the data, leading to the conclusion that the cross section at large missing momenta is strongly enhanced by nucleon-nucleon correlations, with additional enhancement from final-state interactions. The conventional NN correlations present in a modern three-body nuclear wave function, along with a modern reaction mechanism theory, appear sufficient to explain the data; there is no strong indication of a need to include any additional exotic physics, such as quark degrees of freedom.

  15. Electrospun nanowebs of NiO/SnO{sub 2} p-n heterojunctions for enhanced gas sensing

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Yun, E-mail: nwingsaisai@163.com; Zhang, Hui, E-mail: sudawanli@126.com; Sun, Xuhui, E-mail: xhsun@suda.edu.cn

    2016-12-15

    Highlights: • SnO{sub 2}/NiO composite nanowebs were fabricated via the electrospinning method. • The composite nanowebs sensor shows excellent sensing performance to ethanol. • The good performance attributes to the formation of p-type NiO/n-type SnO{sub 2} heterojunctions. - Abstract: Electrospun nanowebs of p-type NiO/n-type SnO{sub 2} heterojunctions were successfully fabricated using a simple electrospinning process followed by thermo-compression and subsequent calcination processes. The morphology, chemical composition and microstructure of the as-spun SnO{sub 2}/NiO nanowebs were well characterized by scanning electron microscopy, high-resolution transmission electron microscopy, X-ray photoelectron spectroscopy and X-ray diffraction. After the calcination, the thinner and porous nanofibers with a high surface area were obtained. The response of the SnO{sub 2}/NiO nanowebs sensor (R{sub a}/R{sub g} = 27.5) is 1 order of magnitude higher than that of the pure SnO{sub 2} nanowebs sensor toward 100 ppm of ethanol with average response and recovery times of ∼2.9 and ∼4.7 s, respectively. Furthermore, the sensor also exhibits high reproducibility and long-term stability. This facile process is versatile for the synthesis of other materials with multilayer nanowebs for different gas sensors and can be extended for various practical applications.

  16. Design, fabrication, and performance analysis of GaN vertical electron transistors with a buried p/n junction

    Energy Technology Data Exchange (ETDEWEB)

    Yeluri, Ramya, E-mail: ramyay@ece.ucsb.edu; Lu, Jing; Keller, Stacia; Mishra, Umesh K. [Electrical and Computer Engineering Department, University of California Santa Barbara, Santa Barbara, California 93106 (United States); Hurni, Christophe A.; Browne, David A.; Speck, James S. [Materials Department, University of California Santa Barbara, Santa Barbara, California 93106 (United States); Chowdhury, Srabanti [School of Electrical, Computer and Energy Engineering, Arizona State University, Tempe, Arizona 85287 (United States)

    2015-05-04

    The Current Aperture Vertical Electron Transistor (CAVET) combines the high conductivity of the two dimensional electron gas channel at the AlGaN/GaN heterojunction with better field distribution offered by a vertical design. In this work, CAVETs with buried, conductive p-GaN layers as the current blocking layer are reported. The p-GaN layer was regrown by metalorganic chemical vapor deposition and the subsequent channel regrowth was done by ammonia molecular beam epitaxy to maintain the p-GaN conductivity. Transistors with high ON current (10.9 kA/cm{sup 2}) and low ON-resistance (0.4 mΩ cm{sup 2}) are demonstrated. Non-planar selective area regrowth is identified as the limiting factor to transistor breakdown, using planar and non-planar n/p/n structures. Planar n/p/n structures recorded an estimated electric field of 3.1 MV/cm, while non-planar structures showed a much lower breakdown voltage. Lowering the p-GaN regrowth temperature improved breakdown in the non-planar n/p/n structure. Combining high breakdown voltage with high current will enable GaN vertical transistors with high power densities.

  17. Nondestructive Evaluation and Endurance Testing of Refurbished T53 Engine Bearings P/N 1-300-015-(02/04).

    Science.gov (United States)

    1987-12-01

    2 Fafnir Reworked 350 123.4 177.7 SpaUl , inner ring, front bearing 3 Fafnir New 350 507 730.1 None 4 Fafnir Reworked 350 411.7 592.8 Spall, inner...Indication 73.4 ITI JR Unk Spa 1 OR 0000 Indents, BK Change ___ Balls 0000 ___ _______ SpaUl -Ig (N)R1271 FAF/ R BK Indication 167.0 STOPPED-High Vibration

  18. Comparison of P···D (D = P,N) with other noncovalent bonds in molecular aggregates.

    Science.gov (United States)

    Adhikari, Upendra; Scheiner, Steve

    2011-11-14

    All the minima on the potential energy surfaces of homotrimers and tetramers of PH(3) are identified and analyzed as to the source of their stability. The same is done with mixed trimers in which one PH(3) molecule is replaced by either NH(3) or PFH(2). The primary noncovalent attraction in all global minima is the BP···D (D = N,P) bond which is characterized by the transfer of charge from a lone pair of the donor D to a σ∗ B-P antibond of the partner molecule which is turned away from D, the same force earlier identified in the pertinent dimers. Examination of secondary minima reveals the presence of other weaker forces, some of which do not occur within the dimers. Examples of the latter include PH···P, NH···P, and PH···F H-bonds, and "reverse" H-bonds in which the source of the electron density is the smaller tail lobe of the donor lone pair. The global minima are cyclic structures in all cases, and exhibit some cooperativity, albeit to a small degree. The energy spacing of the oligomers is much smaller than that in the corresponding strongly H-bonded complexes such as the water trimer. © 2011 American Institute of Physics

  19. Experimental Design for Evaluating Selected Nondestructive Measurement Technologies - Advanced Reactor Technology Milestone: M3AT-16PN2301043

    Energy Technology Data Exchange (ETDEWEB)

    Ramuhalli, Pradeep [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Hirt, Evelyn H. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Pitman, Stan G. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Dib, Gerges [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Roy, Surajit [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Good, Morris S. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Walker, Cody M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2016-07-16

    The harsh environments in advanced reactors (AdvRx) increase the possibility of degradation of safety-critical passive components, and therefore pose a particular challenge for deployment and extended operation of these concepts. Nondestructive evaluation technologies are an essential element for obtaining information on passive component condition in AdvRx, with the development of sensor technologies for nondestructively inspecting AdvRx passive components identified as a key need. Given the challenges posed by AdvRx environments and the potential needs for reducing the burden posed by periodic in-service inspection of hard-to-access and hard-to-replace components, a viable solution may be provided by online condition monitoring of components. This report identifies the key challenges that will need to be overcome for sensor development in this context, and documents an experimental plan for sensor development, test, and evaluation. The focus of initial research and development is on sodium fast reactors, with the eventual goal of the research being developing the necessary sensor technology, quantifying sensor survivability and long-term measurement reliability for nondestructively inspecting critical components. Materials for sensor development that are likely to withstand the harsh environments are described, along with a status on the fabrication of reference specimens, and the planned approach for design and evaluation of the sensor and measurement technology.

  20. A hard oxide semiconductor with a direct and narrow bandgap and switchable p-n electrical conduction.

    Science.gov (United States)

    Ovsyannikov, Sergey V; Karkin, Alexander E; Morozova, Natalia V; Shchennikov, Vladimir V; Bykova, Elena; Abakumov, Artem M; Tsirlin, Alexander A; Glazyrin, Konstantin V; Dubrovinsky, Leonid

    2014-12-23

    An oxide semiconductor (perovskite-type Mn2 O3 ) is reported which has a narrow and direct bandgap of 0.45 eV and a high Vickers hardness of 15 GPa. All the known materials with similar electronic band structures (e.g., InSb, PbTe, PbSe, PbS, and InAs) play crucial roles in the semiconductor industry. The perovskite-type Mn2 O3 described is much stronger than the above semiconductors and may find useful applications in different semiconductor devices, e.g., in IR detectors. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Field programmable gate array (FPGA implementation of novel complex PN-code-generator- based data scrambler and descrambler

    Directory of Open Access Journals (Sweden)

    Shabir A. Parah

    2010-04-01

    Full Text Available A novel technique for the generation of complex and lengthy code sequences using low- length linear feedback shift registers (LFSRs for data scrambling and descrambling is proposed. The scheme has been implemented using VHSIC hardware description language (VHDL approach which allows the reconfigurability of the proposed system such that the length of the generated sequences can be changed as per the security requirements. In the present design consideration the power consumption and chip area requirements are small and the operating speed is high compared to conventional discrete I.C. design, which is a pre-requisite for any system designer. The design has been synthesised on device EP2S15F484C3 of Straitx II FPGA family, using Quarts Altera version 8.1. The simulation results have been found satisfactory and are in conformity with the theoretical observations.

  2. Epidermolysis bullosa pruriginosa - Report of three cases

    Directory of Open Access Journals (Sweden)

    Sengupta Sujata

    2005-03-01

    Full Text Available Epidermolysis bullosa pruriginosa, a genetic mechanobullous disease, is characterized by pruritus, lichenified or nodular prurigo-like lesions, occasional trauma-induced blistering, excoriations, milia, nail dystrophy and albopapuloid lesions, appearing at birth or later. Scarring and prurigo are most prominent on the shins. Treatment is unsatisfactory. We report three such cases: two of them first cousins, are described with history of blisters since childhood, followed by intensely pruritic lesions predominantly on the shins, and dystrophy of toenails, but no albopapuloid lesions or milia. Intact blisters were present in one case, and excoriations were seen in the other two. All of them showed encouraging response to cryotherapy.

  3. Analisis Dimensi Hak Asasi Manusia Terhadap Putusan Hakim dalam Perkara Pencabulan Anak di Bawah Umur (Analisis Konten: Perkara No. 166/PID.B/2006/PN PDG

    Directory of Open Access Journals (Sweden)

    Akmal .

    2012-07-01

    Full Text Available The purpose of this study was to review the judge’s verdict on case No. 166/PID.B/2006/PN PDG in terms of: (1 whether the judge’s verdict fulfills the elements of legal certainty, fairness, and benefit, (2 whether the judge’s verdict relies on the national and international human rights instruments as well as reviewing the aspects of violations of human rights particularly in cases of child abuse. The type of the human rights cases is domestic abuse of under-aged girls. This research used qualitative method with normative judicial approach. Data processing is done using content analysis. The conclusion of the research; (1 Council of Judges needs to understand the ratification of the Child Protection Law and Law on the Elimination of Domestic Violence as well as the International Human Rights Instruments by the Government of the Republic of Indonesia relating to the Convention on Children’s Rights, in order to stress the domestic child abuse as a form of violation against human rights and as a crime against humanity, (2 in order to protect the victims of domestic violence, particularly women and girls, judges should implement the Child Protection Law and Law on the Elimination of Domestic Violence in their verdicts and the Convention of Children’s Right, because the Penal Code KUHP has not guaranteed fully the protection of children and women as primary victims of domestic violence. Key words: human rights, council of judges.

  4. Podejście oparte na ryzyku w świetle wymagań normy PN-EN ISO 9001:2015-10.

    Directory of Open Access Journals (Sweden)

    Romana Zając

    2017-09-01

    Full Text Available W artykule poruszono zagadnienie zarządzania ryzykiem w odniesieniu do organizacji wdrażających system zarządzania jakością zgodny ISO 9001:2015. Opisano proces analizy ryzyka oraz przedstawiono przykładowy opis metodyki oceny ryzyka.

  5. Λ-Doublet Propensities for reactions on competing A' and A'' potential energy surfaces: O(3P)+N2and O(3P)+HCl.

    Science.gov (United States)

    G Jambrina, Pablo; Menendez, Marta; Zanchet, Alexandre; Garcia, Ernesto; Aoiz, F Javier

    2018-02-14

    This work present scattering calculations for the O($^3P$) + N$_2$($^1\\Sigma$) $\\rightarrow$ NO($^2\\Pi$) + N($^4$S) and for the O($^3P$) + HCl($^1\\Sigma$) $\\rightarrow$ OH($^2\\Pi$) + Cl($^2$P) reactions with the focus on the prediction of the $\\Lambda$-doublet populations in which NO and OH are produced. Both reactions can take place on two competing potential energy surfaces of symmetries $^3A'$ and $^3A''$ that correlate reagents with products but with very distinct topographies. As a result, they exhibit very different dynamical behaviors and total reactivity. Using a method that relates the reaction yield on the two competing surfaces to the $\\Lambda$-doublet populations through the explicit consideration of the stereodynamics of the reaction, we predict that the population of NO and OH on the two $\\Lambda$-doublet sates is surprisingly similar for both systems. These results contradict the model that assumes that collisions on the $^3A'$ and $^3A''$ would give rise to products in the $\\Pi(A')$ and $\\Pi(A'')$ states, respectively.

  6. "Joint Workshop on High Confidence Medical Devices, Software, and Systems (HCMDSS) and Medical Device Plug-and-Play (MD PnP) Interoperability"

    Science.gov (United States)

    2008-05-01

    networked biosensors , telesurgery, robotic surgery, physiologic signal QoS (Quality of Service) • Distributed Control & Sensing of Networked Medical...are doing. Donna- Bea Tillman, Ph.D. Director, Office of Device Evaluation Center for Devices and Radiological Health Larry Kessler, Sc.D

  7. Summary Describing Integration of ERM Methodology into Supervisory Control Framework with Software Package Documentation; Advanced Reactor Technology Milestone: M4AT-16PN2301052

    Energy Technology Data Exchange (ETDEWEB)

    Ramuhalli, Pradeep [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Hirt, Evelyn H. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Dib, Gerges [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Veeramany, Arun [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Bonebrake, Christopher A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Roy, Surajit [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2016-09-20

    This project involved the development of enhanced risk monitors (ERMs) for active components in Advanced Reactor (AdvRx) designs by integrating real-time information about equipment condition with risk monitors. Health monitoring techniques in combination with predictive estimates of component failure based on condition and risk monitors can serve to indicate the risk posed by continued operation in the presence of detected degradation. This combination of predictive health monitoring based on equipment condition assessment and risk monitors can also enable optimization of maintenance scheduling with respect to the economics of plant operation. This report summarizes PNNL’s multi-year project on the development and evaluation of an ERM concept for active components while highlighting FY2016 accomplishments. Specifically, this report provides a status summary of the integration and demonstration of the prototypic ERM framework with the plant supervisory control algorithms being developed at Oak Ridge National Laboratory (ORNL), and describes additional case studies conducted to assess sensitivity of the technology to different quantities. Supporting documentation on the software package to be provided to ONRL is incorporated in this report.

  8. "Joint Workshop on High Confidence Medical Devices, Software, and Systems (HCMDSS) and Medical Device Plug-and-Play (MD PnP) Interoperability"

    National Research Council Canada - National Science Library

    Goldman, Julian M

    2008-01-01

    Partial support was requested from TATRC, with joint funding from NSF, for a joint workshop to bring together the synergistic efforts and communities of the High Confidence Medical Devices, Software, and Systems (HCMDSS...

  9. Recycling Matter in the Universe. X-Ray observations of SBS1150+599A (PN 6135.9+55.9)

    Science.gov (United States)

    Tovmassian, Gagik; Tomsick, John; Napiwotzki, Ralf; Yungelson, Lev; Stasinska, Grazyna; Pena, Miriam; Richer, Michael

    2008-01-01

    We present X-ray observations of the close binary nucleus of the planetary nebula SBS 1150+599A obtained with the XMM-Newton satellite. Only one component of the binary can be observed in optical-UV. New X-ray observations show that the previously invisible component is a very hot compact star. This finding allows us to deduce rough values for the basic parameters of the binary. With a high probability the total mass of the system exceeds Chandrasekhar limit and makes the SBS1150+599A one of the best candidate for a supernova type Ia progenitor.

  10. Measurement of Spin Dependent Observables in the $\\overline pN$ Elastic Scattering from 300 to 700 MeV/c

    CERN Multimedia

    2002-01-01

    The aim of the experiment is to measure @*N spin obssservables using a frozen spin target and a high resolution spectrometer (SPES II). The &bar.NN scattering is usually described with NN potentials transformed by G-parity, where the large annihilation cross section (@s^a^n/@s^e^l$>$2) is taken into account. The different theoretical approaches fit reasonably well the existing data on spin integrated cross sections. For the spin dependent observables, the predictions depend consistently on the theoretical inputs.\\\\ \\\\ A strong energy dependence of the @*p polarization Ay(@q) is predicted. We plan to check it measuring the angular distribution of Ay(@q) for @* momenta between 300 and 700 MV/c. Using a deuterium target, measurements of Ay(@q) for @*d in the same energy range will provide information on @*n scattering.\\\\ \\\\ The @* beam hits a 5 mm thick frozen spin target which has a large opening aperture. We expect a polarization of @=~80\\% with a low holding field of (.35Tm). The incident trajectory is de...

  11. PERLINDUNGAN HUKUM DALAM PENDAFTARAN CIPTAAN SENI LUKIS (Studi Kasus Putusan Pengadilan Niaga Medan nomor 05/Hak Cipta/2008/PN. Niaga. Mdn.

    Directory of Open Access Journals (Sweden)

    Abu Churairah

    2017-08-01

    Full Text Available Karya cipta seni lukis yang merupakan salah satu bagian dari Hak atas Kekayaan Intelektual (HAKI yang dilindungi oleh Perundang-undangan, namun masih ada pelanggaran atas ketentuan UU. Pelanggararan yang terjadi seperti pemalsuan atas suatu seni lukis, perebutan hak sebagai pencipta dan pemegang hak cipta atas suatu dasar karya lukisan. Hal ini terjadi karena Ketidaktahuan masyarakat yang menimbulkan salah pengertian mengenai UU No. 19 Tahun 2002 tentang Hak Cipta dimana bahwa negara Indonesia telah  meratifikasi “Berne Convention For The Protection Of Artistic And Literary Works” (Konvensi Berne tentang Perlindungan Karya Seni dan Sastra melalui Keputusan Presiden No.18 Tahun 1997, dan “World Intellectual Property Right Treaty”  (perjanjian Hak Cipta WIPO melalui Keputusan Presiden No. 19 Tahun 1997. Hak cipta hendaknya selalu mendapat perhatian sekaligus pengawasan yang serius dalam perkembangannya, karena merupakan suatu produk hukum yang akan selalu mengalami kemajuan seiring kemajuan pada bidang lainnya, pemerintah harus bekerjasama dengan masyarakat dalam melakukannya, oleh karena itu masyarakat harus lebih peduli dan mau tahu terhadap apa yang terbaik dapat menjadi perlindungan bagi Hak Cipta.

  12. Adjuvant radiation therapy is associated with better oncological outcome compared with salvage radiation therapy in patients with pN1 prostate cancer treated with radical prostatectomy.

    Science.gov (United States)

    Tilki, Derya; Preisser, Felix; Tennstedt, Pierre; Tober, Patrick; Mandel, Philipp; Schlomm, Thorsten; Steuber, Thomas; Huland, Hartwig; Schwarz, Rudolf; Petersen, Cordula; Graefen, Markus; Ahyai, Sascha

    2017-05-01

    To analyse the comparative effectiveness of no treatment (NT) or salvage radiation therapy (sRT) at biochemical recurrence (BCR) vs adjuvant radiation therapy (aRT) in patients with lymph node (LN)-positive prostate cancer (PCa) after radical prostatectomy (RP). A total of 773 patients with LN-positive PCa at RP, with or without additional radiation therapy (RT), in the period 2005-2013, were retrospectively analysed. Cox regression analysis was used to assess factors influencing BCR and metastasis-free survival (MFS). Propensity score-matched analyses were performed. The median follow-up for the entire patient group was 33.8 months. Four-year BCR-free and MFS rates were 43.3% and 86.6%, respectively, for all patients. In multivariate analysis, NT/sRT (n = 505) was an independent risk factor for BCR and metastasis compared with aRT (n = 213). The superiority of aRT was confirmed after propensity score matching. The 4-year MFS in the matched cohort was 82.5% vs 91.8% for the NT/sRT and aRT groups, respectively (P = 0.02). Early sRT (pre-RT prostate-specific antigen [PSA] ≤0.5 ng/mL) compared with sRT at PSA >0.5 ng/mL was significantly associated with a lower risk of metastasis. Patients with LN-positive PCa who received aRT had a significantly better oncological outcome than patients with NT/sRT, independent of tumour characteristics. Patients with early sRT had higher rates of response and better MFS than patients with pre-RT PSA >0.5 ng/mL. © 2016 The Authors BJU International © 2016 BJU International Published by John Wiley & Sons Ltd.

  13. In Fond Memory of Scholar and a Good Man (To the 80 anniversary since the birth of P.N. Starostin

    Directory of Open Access Journals (Sweden)

    Drozdova Galina I.,

    2016-09-01

    Full Text Available It is a dedication to the 80th birthday anniversary since the birth of prominent Kazan archaeologist Petr N. Starostin (24.07.1936 – 4.07.2012, an outstanding researcher of Volga and Kama archaeological cultures, who made an invaluable contribution to the studies of the Pyany Bor, Azelino and Imenkovo cultures.

  14. Podejście oparte na ryzyku w świetle wymagań normy PN-EN ISO 9001:2015-10.

    OpenAIRE

    Romana Zając

    2017-01-01

    W artykule poruszono zagadnienie zarządzania ryzykiem w odniesieniu do organizacji wdrażających system zarządzania jakością zgodny ISO 9001:2015. Opisano proces analizy ryzyka oraz przedstawiono przykładowy opis metodyki oceny ryzyka.

  15. Molecular Cloning, Expression of minD Gene from Lactobacillus acidophilus VTCC-B-871 and Analyses to Identify Lactobacillus rhamnosus PN04 from Vietnam Hottuynia cordata Thunb.

    OpenAIRE

    Nguyen, Tu Hoang Khue; Doan, Vinh Thi Thanh; Ha, Ly Dieu; Nguyen, Huu Ngoc

    2013-01-01

    The minD gene encoding an inhibitor cell division MinD homolog from Lactobacillus acidophilus VTCC-B-871 was cloned. We showed that there were 97 % homology between minD genes of L. acidophilus VTCC-B-871 and Lactobacillus rhamnosus GG and Lactobacillus rhamnosus Lc705. Based on the analysis of the DNA sequence data from the L. rhamnosus genome project and sequenced minD gene of L. acidophilus VTCC-B-871, a pair of primers was designed to identified the different minD genes from L. acidophilu...

  16. Topological Insulator Bi2Se3/Si-Nanowire-Based p-n Junction Diode for High-Performance Near-Infrared Photodetector.

    Science.gov (United States)

    Das, Biswajit; Das, Nirmalya S; Sarkar, Samrat; Chatterjee, Biplab K; Chattopadhyay, Kalyan K

    2017-07-12

    Chemically derived topological insulator Bi2Se3 nanoflake/Si nanowire (SiNWs) heterojunctions were fabricated employing all eco-friendly cost-effective chemical route for the first time. X-ray diffraction studies confirmed proper phase formation of Bi2Se3 nanoflakes. The morphological features of the individual components and time-evolved hybrid structures were studied using field emission scanning electron microscope. High resolution transmission electron microscopic studies were performed to investigate the actual nature of junction whereas elemental distributions at junction, along with overall stoichiometry of the samples were analyzed using energy dispersive X-ray studies. Temperature dependent current-voltage characteristics and variation of barrier height and ideality factor was studied between 50 and 300 K. An increase in barrier height and decrease in the ideality factor were observed with increasing temperature for the sample. The rectification ratio (I+/I-) for SiNWs substrate over pristine Si substrate under dark and near-infrared (NIR) irradiation of 890 nm was found to be 3.63 and 10.44, respectively. Furthermore, opto-electrical characterizations were performed for different light power intensities and highest photo responsivity and detectivity were determined to be 934.1 A/W and 2.30 × 1013 Jones, respectively. Those values are appreciably higher than previous reports for topological insulator based devices. Thus, this work establishes a hybrid system based on topological insulator Bi2Se3 nanoflake and Si nanowire as the newest efficient candidate for advanced optoelectronic materials.

  17. Observations of HNO3, ΣAN, ΣPN and NO2 fluxes: evidence for rapid HOx chemistry within a pine forest canopy

    Directory of Open Access Journals (Sweden)

    D. K. Farmer

    2008-07-01

    Full Text Available Measurements of exchange of reactive nitrogen oxides between the atmosphere and a ponderosa pine forest in the Sierra Nevada Mountains are reported. During winter, we observe upward fluxes of NO2, and downward fluxes of total peroxy and peroxy acyl nitrates (ΣPNs, total gas and particle phase alkyl and multifunctional alkyl nitrates (ΣANs(g+p, and the sum of gaseous HNO3 and semi-volatile NO3− particles (HNO3(g+p. We use calculations of the vertical profile and flux of NO, partially constrained by observations, to show that net midday ΣNOyi fluxes in winter are –4.9 ppt m s−1. The signs and magnitudes of these wintertime individual and ΣNOyi fluxes are in the range of prior measurements. In contrast, during summer, we observe downward fluxes only of ΣANs(g+p, and upward fluxes of HNO3(g+p, ΣPNs and NO2 with signs and magnitudes that are unlike most, if not all, previous observations and analyses of fluxes of individual nitrogen oxides. The results imply that the mechanisms contributing to NOy fluxes, at least at this site, are much more complex than previously recognized. We show that the observations of upward fluxes of HNO3(g+p and σPNs during summer are consistent with oxidation of NO2 and acetaldehyde by an OH x residence time of 1.1×1010 molec OH cm−3 s, corresponding to 3 to 16×107 molecules cm−3 OH within the forest canopy for a 420 to 70 s canopy residence time. We show that ΣAN(g+p fluxes are consistent with this range in OH if the reaction of OH with ΣANs produces either HNO3 or NO2 with a 6–30% yield. Calculations of NO fluxes constrained by the NO2 observations and the inferred OH indicate that NOx fluxes are downward into the canopy because of the substantial conversion of NOx to HNO3 and σPNs in the canopy. Even so, we derive that NOx emission fluxes of ~15 ng(N m−2 s−1 at midday during summer are required to balance the NOx and NOy flux budgets. These fluxes are partly explained by estimates of soil emissions (estimated to be between 3 and 6 ng(N m−2 s-1. One possibility for the remainder of the NOx source is large HONO emissions. Alternatively, the 15 ng(N m−2 s−1 emission estimate may be too large, and the budget balanced if the deposition of HNO3 and σPNs is slower than we estimate, if there are large errors in either our understanding of peroxy radical chemistry, or our assumptions that the budget is required to balance because the fluxes do not obey similarity theory.

  18. The Search and Study of Low-mass Scalar Mesons in the Reaction np -> npPi+Pi- AT Pn=3.83 Gev/c

    CERN Document Server

    Troyan, Yu A; Troyan, A Yu; Plekhanov, E B; Jerusalimov, A P; Arakelian, S G

    2010-01-01

    This work is devoted to search and study scalar sigma0 0+[0++] - mesons in the system of Pi+Pi- from the reaction np -> npPi+Pi- at the impulse of the quasimonochromatic neutrons c from the data obtained in an exposure of the 1m H2 bubble chamber of LHE (JINR)The resonance with and has been found out in effective mass distribution. Value of a statistical deviation of this peculiarity from a background is more than four. Spin of the resonance has been estimated, which, with high probability, is equal 0. The other quantum numbers of the resonance have been estimated.

  19. Gender Differences in Examinee Performance on the Step 2 Clinical Skills[R] Data Gathering (DG) and Patient Note (PN) Components

    Science.gov (United States)

    Swygert, Kimberly A.; Cuddy, Monica M.; van Zanten, Marta; Haist, Steven A.; Jobe, Ann C.

    2012-01-01

    Multiple studies examining the relationship between physician gender and performance on examinations have found consistent significant gender differences, but relatively little information is available related to any gender effect on interviewing and written communication skills. The United States Medical Licensing Examination (USMLE[R]) Step 2…

  20. High injection and carrier pile-up in lattice matched InGaAs/InP PN diodes for thermophotovoltaic applications

    Science.gov (United States)

    Ginige, R.; Cherkaoui, K.; Wong Kwan, V.; Kelleher, C.; Corbett, B.

    2004-03-01

    This article analyzes and explains the observed temperature dependence of the forward dark current of lattice matched In0.53Ga0.47As on InP diodes as a function of voltage. The experimental results show, at high temperatures, the characteristic current-voltage (I-V) curve corresponding to leakage, recombination, and diffusion currents, but at low temperatures an additional region is seen at high fields. We show that the onset of this region commences with high injection into the lower-doped base region. The high injection is shown by using simulation software to substantially alter the minority carrier concentration profile in the base, emitter and consequently the quasi-Fermi levels (QFL) at the base/window and the window/cap heterojunctions. We show that this QFL splitting and the associated electron "pile-up" (accumulation) at the window/emitter heterojunction leads to the observed pseudo-n=2 region of the current-voltage curve. We confirm this phenomenon by investigating the I-V-T characteristics of diodes with an InGaAsP quaternary layer (Eg=1 eV) inserted between the InP window (Eg=1.35 eV) and the InGaAs emitter (Eg=0.72 eV) where it serves to reduce the barrier to injected electrons, thereby reducing the "pile-up." We show, in this case that the high injection occurs at a higher voltage and lower temperature than for the ternary device, thereby confirming the role of the "accumulation" in the change of the I-V characteristics from n=1 to pseudo-n=2 in the ternary latticed matched device. This is an important phenomenon for consideration in thermophotovoltaic applications. We, also show that the activation energy at medium and high voltages corresponds to the InP/InGaAs conduction band offset at the window/emitter heterointerface.

  1. Observation of a Resonance at $2.36-GeV/c^{2}$ in 400 GeV/c $pN$ Interactions

    Energy Technology Data Exchange (ETDEWEB)

    Woosley, James K. [Vanderbilt Univ., Nashville, TN (United States)

    1987-08-01

    The purpose of this dissertation is to present evidence for a resonance in an analysis of data obtained by Fermi National Accelerator Laboratory (FNAL) experiment E623. This experiment was performed in the FNAL Multiparticle Spectrometer (MPS) utilizing a 400 GeV/c proton beam on a nuclear target. The MPS for E623 included a hardware trigger designed to enhance the inclusive $K^+K^-K^+ K^-$ sample, with low $K^+ K^-$ mass to enhance the detection of pairs of $\\phi$ mesons observed through the $\\phi \\to K^+ K^-$ decay....

  2. Analytic 1D pn junction diode photocurrent solutions following ionizing radiation and including time-dependent changes in the carrier lifetime.

    Energy Technology Data Exchange (ETDEWEB)

    Axness, Carl L.; Keiter, Eric Richard; Kerr, Bert (New Mexico Tech, Socorro, NM)

    2011-04-01

    Circuit simulation tools (e.g., SPICE) have become invaluable in the development and design of electronic circuits in radiation environments. These codes are often employed to study the effect of many thousands of devices under transient current conditions. Device-scale simulation tools (e.g., MEDICI) are commonly used in the design of individual semiconductor components, but require computing resources that make their incorporation into a circuit code impossible for large-scale circuits. Analytic solutions to the ambipolar diffusion equation, an approximation to the carrier transport equations, may be used to characterize the transient currents at nodes within a circuit simulator. We present new transient 1D excess carrier density and photocurrent density solutions to the ambipolar diffusion equation for low-level radiation pulses that take into account a finite device geometry, ohmic fields outside the depleted region, and an arbitrary change in the carrier lifetime due to neutron irradiation or other effects. The solutions are specifically evaluated for the case of an abrupt change in the carrier lifetime during or after, a step, square, or piecewise linear radiation pulse. Noting slow convergence of the raw Fourier series for certain parameter sets, we use closed-form formulas for some of the infinite sums to produce 'partial closed-form' solutions for the above three cases. These 'partial closed-form' solutions converge with only a few tens of terms, which enables efficient large-scale circuit simulations.

  3. Penjualan Agunan Secara Lelang Tanpa Persetujuan Pemberi Hak Tanggungan Diikuti Gugatan Perbuatan Melawan Hukum (Studi Putusan Nomor 348/ PDT.G/ 2009/PN.TNG)

    OpenAIRE

    Siahaan, Flaming Vretig Samuel Blessry

    2014-01-01

    Dalam kehidupan masyarakat, masyarakat sering menggunakan agunan sebagai cara untuk memperoleh suatu barang, Agunan dalam kamus bahasa Indonesia ialah “ jaminan atau juga tanggungan’’ jaminan berarti adanya sesuatu yang bisa menjadikan pegangan bagi kreditur ketika debitur ingin memperoleh suatu barang yang diinginkan, sebelum melunasi barang tersebut, maka debitur harus memberikan jaminannya, Dalam hal lelang telah diperintahkan oleh Ketua Pengadilan Negeri, maka lelang tersebut hanya da...

  4. Formation of a p-n heterojunction on GaP photocathodes for H-2 production providing an open-circuit voltage of 710 mV

    DEFF Research Database (Denmark)

    Malizia, Mauro; Seger, Brian; Chorkendorff, Ib

    2014-01-01

    Photocatalytic water splitting for the sustainable production of hydrogen using a two-photon tandem device requires careful optimization of the semiconductors used as photon absorbers. In this work we show how the open-circuit voltage of photocathodes for the hydrogen evolution reaction based on ...

  5. Epidermolysis bullosa pruriginosa

    Directory of Open Access Journals (Sweden)

    Yesudia P

    2000-01-01

    Full Text Available Epidermolysis bullosa pruriginosa is a recently described variant of epidermolysis bullosa dystrophica. It is characterised by pruritic nodular prurigo like lesions, milia and with a histopathology of a subepidermal blister. We report 3 cases of this new variant.

  6. Epidermolysis bullosa pruriginosa: A report of two cases

    Directory of Open Access Journals (Sweden)

    Varadraj Vasant Pai

    2014-01-01

    Full Text Available Epidermolysis bullosa (EB pruriginosa is a very rare pattern of dystrophic EB caused by type VII collagen gene mutation, with distinctive clinico-pathological features. It is characterized by nodular prurigo-like lichenified lesions, nail dystrophy, and variable presence of albopapuloid lesions. We report two such cases.

  7. Anafylaktisk shock efter intradermal injektion af steroidpræparat

    DEFF Research Database (Denmark)

    Meyer, Martin Willy; Zachariae, Claus; Garvey, Lene Heise

    2015-01-01

    Carboxymethylcellulose (CMC) is a derivative of cellulose found in many food products, pharmaceuticals and cosmetics. Allergy to CMC in parenteral corticosteroid preparations leading to anaphylaxis is rare, but has previously been reported. We report a case of a 52-year-old woman with prurigo nod...

  8. Study of the elastic scattering and of the (p,n) charge exchange reaction with neutron-rich light exotic beams; Etude de la diffusion elastique et de la reaction d`echange de charge (p,n) avec des faisceaux exotiques legers riches en neutrons

    Energy Technology Data Exchange (ETDEWEB)

    Cortina Gil, D.

    1996-07-05

    We have measured at GANIL, with the high resolution spectrometer SPEG, the elastic scattering of several neutron rich secondary beams ({sup 6}He, {sup 10}Be and {sup 11}Be) on a polypropylene target and the charge exchange reaction p({sup 6}He, {sup 6}Li)n. These exotic beams were produced by nuclear fragmentation and re-focalized with the SISSI device (superconducting solenoids). The signature of a halo structure in these nuclei has been analysed. Special attention has been paid to several aspects of the associated calculations namely, the proton and neutron density distributions and the small binding energy for the last nucleons in these exotic nuclei. Break-up mechanisms are seen to play an important role in these nuclei. 100 refs.

  9. KAJIAN YURIDIS ATAS PENANGKAPAN DAN PENAHANAN OLEH PENYIDIK PEGAWAI NEGERI SIPIL BERDASARKAN HUKUM ACARA PIDANA DI INDONESIA (Studi Kasus PutusanNomor: 15/Pra.Pid/2012/PN.Mdn dan Putusan Nomor: 01/Pid.Pra/Per/2012/PN.Stb

    Directory of Open Access Journals (Sweden)

    Hubertus Manao

    2013-12-01

    Full Text Available Dalam sistem peradilan pidana yang dianut dalam KUHAP terdapat berbagai lembaga penegak hukum yang menjadi institusi pelaksana peraturan perundang-undangan dan merupakan bagian yang tidak terpisahkan satu sama lainnya yaitu kepolisian, kejaksaan, pengadilan, lembaga pemasyarakatan dan advokat/pengacara. Sistem peradilan pidana adalah intitusi kolektif dimana seorang pelaku tindak pidana melalui suatu proses sampai tuntutan ditetapkan atau penjatuhan hukuman telah diputuskan.Berbagai undang-undang yang memberikan kewenangan penyidikan kepada PPNS menempatkan Penyidik Pegawai Negeri Sipil sebagai salah satu lembaga yang menjalankan fungsi penegakan hukum di berbagai sektor dalam kerangka sistem peradilan pidana.Dalam praktek penegakan hukum, penyidik pegawai negeri sipil demi kepentingan penyidikan dapat melakukan penangkapan dan penahananterhadap tersangka tanpa melibatkan penyidik Polri sehingga memunculkan permasalahan mengenai legalitas penangkapan dan penahanan tersebut. Permasalahan ini dibahas dengan menggunakan teori sistem peradilan pidana yang berkaitan dengan upaya pengendalian kejahatan melalui kerjasama dan koordinasi di antara lembaga-lembaga yang oleh undang-undang diberi tugas untuk itu.

  10. [Risk factors and allergic manifestations associated with atopic dermatitis in Lomé (Togo): a multicenter study of 476 children aged 0-15 years].

    Science.gov (United States)

    Técléssou, J N; Mouhari-Toure, A; Akakpo, S; Bayaki, S; Boukari, O B T; Elégbédé, Y M; Gnassingbé, W; Kombaté, K; Yédomon, H; Pitché, P

    2016-01-01

    The aim of this study was to determine the prevalence and document the risk factors and allergic reactions associated with atopic dermatitis (AD) in children in Lomé. This cross-sectional multicenter study took place from March to June 2013 in four health facilities in Lomé. It applied the criteria of the United Kingdom Working Party (UKWP). We included 476 children aged 0-15 years who came for a vaccination or pediatric consultation; 31.3% were diagnosed with AD. The mean age of the children with AD was 33.91 ± 37 months, and the sex ratio (M/F) 0.96. In the univariate analysis, several risk factors and allergic reactions were significantly associated with AD including weaning, asthma, allergic conjunctivitis, allergic rhinitis, food allergy, alopecia, seborrheic dermatitis in infants, and prurigo. In the multivariate analysis, AD was associated with prurigo (aOR = 15.59, 95% CI = 7.54 to 32.21), allergic rhinitis (aOR = 7.51, 95% CI = 4.31 to 13.10), and food allergy (aOR = 5.32 95% CI = 1.20 to 23.48) were associated with AD. AD is common in children in Lomé. Prurigo, allergic rhinitis and food allergy are allergic manifestations associated with it. These results deserve confirmation by a prospective study over a longer period.

  11. Effect of ProNectin F derivatives on cell attachment and proliferation.

    Science.gov (United States)

    Somamoto, Satoshi; Tabata, Yasuhiko

    2013-02-01

    ProNectin F (PnF) was chemically modified by introducing some functional groups to prepare various derivatives of primary amino (PnF-N₁), tertiary amino (PnF-N₃), quaternary ammonium (PnF-N₄), carboxyl (PnF-COOH) and sulfonyl groups (PnF-SO₃H). When C3H10T1/2 cells were cultured on non-treated dishes coated with the derivatives, the number of mesenchymal cells attached to the culture dishes increased for the coating with PnF-COOH and PnF-SO₃H, even at their low adsorption amount. The cytotoxicity was high for the coating of PnF-N₁ and PnF-N₄ compared with that of the PnF-N₃, PnF-COOH and PnF-SO₃H. The treatment with integrin α5 and αV antibodies suppressed the cell attachment to the dishes coated with PnF-COOH and PnF-SO₃H. The phosphorylation of extracellular signal-regulated kinase (ERK) was upregulated for cells attached to the dishes coated with PnF-COOH and PnF-SO₃H, indicating their enhanced proliferation. It is concluded that the chemical derivatization of PnF enhanced the ability of cell attachment and proliferation. Copyright © 2012 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  12. Integrated Advanced Microwave Sounding Unit-A(AMSU-A). Performance Verification Report, METSAT Phase Locked Oscillator Assembly, P/N 1348360-1, S/N's F07 and F08

    Science.gov (United States)

    Pines, D.

    1998-01-01

    Two Flight Model AMSU-A Phase Locked Oscillators (PIN 1348360-1, S/N F07 and F08) have been tested per AES Test Procedure AE-26758 Rev. B, which include full functional testing, vibration testing, thermal testing, and AM/FM Noise testing. Both assemblies satisfactorily passed all performance requirements of the AE-26633 Product Specification. During the thermal cycling of both units, spurs developed 1 MHz from the carrier when the units were cold, and TARs were written to document the anomaly. The symptoms observed in both cases were consistent with inadequate tuning. The units were successfully re-tuned. In the case of F08, re-tuning required a design change which allowed a greater range of possible values for tuning resisters. Both units completed thermal cycling without further delay. The results of the required tests are presented in the following section as test data. As indicated on the test data sheets, all measured data passed all requirements.

  13. Integrated Advanced Microwave Sounding Unit-A (AMSU-A). Performance Verification Report: Final Comprehensive Performance Test Report, P/N 1331720-2TST, S/N 105/A1

    Science.gov (United States)

    Platt, R.

    1999-01-01

    This is the Performance Verification Report, Final Comprehensive Performance Test (CPT) Report, for the Integrated Advanced Microwave Sounding Unit-A (AMSU-A). This specification establishes the requirements for the CPT and Limited Performance Test (LPT) of the AMSU-1A, referred to here in as the unit. The sequence in which the several phases of this test procedure shall take place is shown.

  14. Integrated Advanced Microwave Sounding Unit-A (AMSU-A). Performance Verification Reports: Final Comprehensive Performance Test Report, P/N: 1356006-1, S.N: 202/A2

    Science.gov (United States)

    Platt, R.

    1998-01-01

    This is the Performance Verification Report. the process specification establishes the requirements for the comprehensive performance test (CPT) and limited performance test (LPT) of the earth observing system advanced microwave sounding unit-A2 (EOS/AMSU-A2), referred to as the unit. The unit is defined on drawing 1356006.

  15. Structure of phosphorus clusters using simulated annealing. II. P9, P10, P11, anions P2-4, P2-10, P3-11, and cations P+n to n=11

    Science.gov (United States)

    Jones, R. O.; Seifert, G.

    1992-05-01

    Previous calculations on the structures of isomers of phosphorus clusters P2 to P8 [density functional calculations with simulated annealing (SA), J. Chem. Phys. 92, 6710 (1990)] have been extended to P9, P10, and P11. The tendency of phosphorus to form tubular structures is already evident in clusters of this size. We have also performed calculations on additional isomers of the hexamer P6, positive ions up to P+11, and the P2-4, P2-10, and P3-11 anions. Ionization energies agree well with available measurements [P1 to P4] and show trends that can be correlated with the structures and the measured relative abundances of the ions. The calculated structure of P3-11 agrees very well with x-ray diffraction data, and we observe isomerization in P9 resulting from charge transfer. A simplified SA scheme using a linear combination of atomic orbitals (LCAO) has been used to aid the analysis of the results.

  16. Towards monomaterial p-n junctions: Single-step fabrication of tin oxide films and their non-destructive characterisation by angle-dependent X-ray photoelectron spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Krzywiecki, Maciej, E-mail: Maciej.Krzywiecki@polsl.pl [Max-Planck-Institut für Eisenforschung GmbH, Max-Planck-Str. 1, 40237 Düsseldorf (Germany); Institute of Physics–CSE, Silesian University of Technology, Konarskiego 22B, 44-100 Gliwice (Poland); Sarfraz, Adnan; Erbe, Andreas [Max-Planck-Institut für Eisenforschung GmbH, Max-Planck-Str. 1, 40237 Düsseldorf (Germany)

    2015-12-07

    The application of a non-destructive method for characterization of electronic structure of an ultra-thin SnO{sub 1

  17. Interface-enhanced sensitivity of photoconductivity to the electric current and magnetic field in La0.67Ca0.33MnO3/Nb-SrTiO3 p-n junctions

    Science.gov (United States)

    Wang, S.; Ma, Z. Z.; Xiong, J. J.; Li, C. J.; Hou, Y. H.; Ma, T. X.; Xiong, C. M.; Dou, R. F.; Nie, J. C.

    2016-12-01

    The effects of electric current and magnetic field on the photoconductivity (PC) of La0.67Ca0.33MnO3 (LCMO) films have been investigated within a comparative study on LCMO films on an n-type semiconducting Nb-doped SrTiO3 (NSTO) and insulating SrTiO3 (STO) substrates separately. At room temperature, LCMO on NSTO (LCMO/NSTO) was found to show remarkable PC effect than that on STO (LCMO/STO). More attractive is that, compared with that of LCMO/STO, the room-temperature PC of LCMO/NSTO also shows a high sensitivity to the change of current or magnetic field: for LCMO/NSTO under a light illumination with an intensity of 60 mW/cm2, the increment of current yields a decreases of PC at a rate of 7.6%/μA, while an application of magnetic field of 1.2 T can suppress PC by a percentage as high as ˜20%. In contrast, under the same stimulus of current or field, PC of LCMO/STO remains almost unchanged. The phenomena can be explained based on the interface effects correlated with the photocarrier injection, current shunting, and magnetic tunability occurred at the interface. This work demonstrates that manganite-based heterojunctions with interface engineering are promising for developing a new type of photoelectric device with high sensitivity and multifunctionality.

  18. Cross-section measurement of the 169 Tm p,n reaction for the production of the therapeutic radionuclide 169 Yb and comparison with its reactor-based generation.

    Science.gov (United States)

    Spahn, I; Takács, S; Shubin, Yu N; Tárkányi, F; Coenen, H H; Qaim, S M

    2005-08-01

    The radionuclide (169)Yb (T(1/2)=32.0 d) is potentially important for internal radiotherapy. It is generally produced using a nuclear reactor. In this work the possibility of its production at a cyclotron was investigated. A detailed determination of the excitation function of the (169)Tm(p,n)(169)Yb reaction was done over the proton energy range up to 45 MeV using the stacked-foil technique and high-resolution gamma-ray spectrometry. The integral yield of (169)Yb was calculated. Over the optimum energy range E(P)=16-->7 MeV the yield amounts to 1.5 MBq/micro Ah and is thus rather low. A comparison of this production route with the established (168)Yb(n,gamma)(169)Yb reaction at a nuclear reactor is given. The (169)Yb yield via the reactor route is by several orders of magnitude higher than by the cyclotron method. The latter procedure, however, leads to "no-carrier-added" product.

  19. Parenteral nutrition following intensive cytotoxic therapy: an exploratory study on the need for parenteral nutrition after various treatment approaches for haematological malignancies

    NARCIS (Netherlands)

    Iestra, J. A.; Fibbe, W. E.; Zwinderman, A. H.; Romijn, J. A.; Kromhout, D.

    1999-01-01

    Patients receiving intensive cytotoxic therapy are traditionally supported with parenteral nutrition (PN), although it is unclear whether all patients benefit from PN. This study aimed to identify regimen-associated differences in PN requirements, to reveal discrepancies between the number of PN

  20. 77 FR 73343 - Airworthiness Directives; Airbus Airplanes

    Science.gov (United States)

    2012-12-10

    ... Tested or Modified SOGERMA pilot and co-pilot seats having P/N 2510112 series (all suffixes) or P/N 2510113 series (all suffixes) that, before the effective date of this AD, have already passed the tensile... identified as P/N 2510112 series (all suffixes), or P/N 2510113 series (all suffixes): Within 6 months after...