WorldWideScience

Sample records for preparing district performance

  1. Performance analysis of hybrid district heating system

    DEFF Research Database (Denmark)

    Mikulandric, Robert; Krajačić, Goran; Khavin, Gennadii

    2013-01-01

    as problems related to transportation, storage and environmental impacts of biomass and waste utilisation. Implementation of heat storages in district heating systems could contribute to integration of intermittent energy sources. Hybridisation of heat production facility combines two or more different energy...... that combines different energy sources for heat production will be used. The work has been carried out in scope of 4th Generation District Heating Technologies and Systems project.......District heating system could contribute to more efficient heat generation through cogeneration power plants or waste heat utilization facilities and to increase of renewable energy sources share in total energy consumption. In the most developed EU countries, renewable energy sources have been...

  2. Performance analysis of hybrid district heating system

    DEFF Research Database (Denmark)

    Mikulandric, Robert; Krajačić, Goran; Khavin, Gennadii

    2013-01-01

    as problems related to transportation, storage and environmental impacts of biomass and waste utilisation. Implementation of heat storages in district heating systems could contribute to integration of intermittent energy sources. Hybridisation of heat production facility combines two or more different energy...... more extensively used in district heating systems either separately or as a supplement to traditional fossil fuels in order to achieve national energy policy objectives. However, they are still facing problems such as high intermittences, high energy production costs and low load factors as well...

  3. Low Temperature District Heating Consumer Unit with Micro Heat Pump for Domestic Hot Water Preparation

    DEFF Research Database (Denmark)

    Zvingilaite, Erika; Ommen, Torben Schmidt; Elmegaard, Brian

    2012-01-01

    In this paper we present and analyse the feasibility of a district heating (DH) consumer unit with micro heat pump for domestic hot water (DHW) preparation in a low temperature (40 °C) DH network. We propose a micro booster heat pump of high efficiency (COP equal to 5,3) in a consumer DH unit...... in order to boost the temperature of the district heating water for heating the DHW. The paper presents the main designs of the suggested system and different alternative micro booster heat pump concepts. Energy efficiency and thermodynamic performance of these concepts are calculated and compared....... The results show that the proposed system has the highest efficiency. Furthermore, we compare thermodynamic and economic performance of the suggested heat pump-based concept with different solutions, using electric water heater. The micro booster heat pump system has the highest annualised investment (390 EUR...

  4. Performance Analysis of a Hybrid District Heating System

    DEFF Research Database (Denmark)

    Mikulandric, Robert; Krajačić, Goran; Duic, Neven

    2015-01-01

    Hybridisation of district heating systems can contribute to more efficient heat generation through cogeneration power plants or through the share increase of renewable energy sources in total energy consumption while reducing negative aspects of particular energy source utilisation. In this work......, the performance of a hybrid district energy system for a small town in Croatia has been analysed. Mathematical model for process analysis and optimisation algorithm for optimal system configuration has been developed and described. The main goal of the system optimisation is to reduce heat production costs....... Several energy sources for heat production have been considered in 8 different simulation cases. Simulation results show that the heat production costs could be reduced with introduction of different energy systems into an existing district heating system. Renewable energy based district heating systems...

  5. Environmental and Thermal Performance of District Heating Pipes

    Energy Technology Data Exchange (ETDEWEB)

    Froeling, Morgan

    2002-06-01

    The introduction of district heating has reduced the environmental impact from local heat production in urban areas. However, in order to fit into a sustainable society, district heating must be continuously developed according to the increasing demands on activities in a society moving towards sustainability. Our technical improvements must result in environmental improvements. This thesis focuses on the environmental performance of the distribution system - the district heating pipes. The purpose of this research is to understand how the distribution system can be improved. The information presented in this thesis can be used to identify possibilities for improving the environmental performance of different life cycle phases of the distribution system as well as a baseline when evaluating new technical developments. The heat losses during use of the pipes are of large importance for the environmental impact of district heating pipes. Such heat losses can be modelled if the mass transfer parameters for gases in the polyurethane insulation and the polyethylene casing are known. The diffusion coefficients, the permeability coefficients and the solubility coefficients and their temperature dependence have been determined for cyclopentane, carbon dioxide, nitrogen, and oxygen. The same parameters have been studied for the blowing agent alternative HFC-365mfc at room temperature. The long-term thermal performance of district heating pipes has been modelled using effective permeabilities for the pipe construction. Environmental consequences of heat losses during the use phase of district heating pipes have been compared with the impacts from production of the pipes and from construction of the district heating network. The use of the district heating pipes is the most important of the studied life cycle phases. Thus, it is very important to minimise heat losses from the pipes. The heat losses will for some district heating pipes increase notably during use due to foam

  6. Managing School Districts for High Performance: Instructor's Guide

    Science.gov (United States)

    Childress, Stacey, Ed.; Elmore, Richard F., Ed.; Grossman, Allen, Ed.; Johnson, Susan Moore, Ed.

    2007-01-01

    This companion Instructor's Guide to "Managing School Districts for High Performance: Cases in Public Education Leadership" includes detailed teaching notes on each case in the coursebook, with an emphasis on making cases drawn from other disciplines relevant to education administrators. Both experienced instructors and those new to the…

  7. 77 FR 58354 - Bend-Fort Rock Ranger District; Oregon; Withdrawal of Notice for Preparation of an Environmental...

    Science.gov (United States)

    2012-09-20

    ...; ] DEPARTMENT OF AGRICULTURE Forest Service Bend-Fort Rock Ranger District; Oregon; Withdrawal of Notice for... Bend-Fort Rock Ranger District and FHWA are withdrawing their intent to prepare an Environmental Impact... FURTHER INFORMATION CONTACT: Amy Tinderholt, Project Leader, Bend- Fort Rock Ranger District,...

  8. Comparison of Transformational Leadership Practices: Implications for School Districts and Principal Preparation

    Science.gov (United States)

    Quin, Jeff; Deris, Aaron; Bischoff, Greg; Johnson, James T.

    2015-01-01

    The purpose of this study was to determine the leadership practices needed to improve academic achievement and generate positive change in school organizations. The study was also conducted to provide insight to principal preparation programs and school districts about effective transformational leadership practices. A quantitative research method…

  9. Thermal performance of solar district heating plants in Denmark

    DEFF Research Database (Denmark)

    Furbo, Simon; Perers, Bengt; Bava, Federico

    2014-01-01

    The market for solar heating plants connected to district heating systems is expanding rapidly in Denmark. It is expected that by the end of 2014 the 10 largest solar heating plants in Europe will be located in Denmark. Measurements from 23 Danish solar heating plants, all based on flat plate solar...... collectors mounted on the ground, shows measured yearly thermal performances of the solar heating plants placed in the interval from 313 kWh/m² collector to 493 kWh/m² collector with averages for all plants of 411 kWh/m² collector for 2012 and 450 kWh/m² collector for 2013. Theoretical calculations show...... of the cost/performance ratio for solar collector fields, both with flat plate collectors and with concentrating tracking solar collectors. It is recommended to continue monitoring and analysis of all large solar heating plants to document the reliability of the solar heating plants. It is also recommended...

  10. Analysis Of Influence Of Spatial Planning On Performance Of Regional Development At Waropen District. Papua Indonesia

    Directory of Open Access Journals (Sweden)

    Suwandi

    2015-08-01

    Full Text Available The various problems in regional spatial planning in Waropen District Papua shows that the Spatial Planning RTRW of Waropen District Papua drafted in 2010 has not had a positive contribution to the settlement of spatial planning problems. This is most likely caused by the inconsistency in the spatial planning. This study tried to observe the consistency of spatial planning as well as its relation to the regional development performance. The method used to observe the consistency of the preparation of guided Spatial Planning RTRW is the analysis of comparative table followed by analysis of verbal logic. In order to determine if the preparation of Spatial Planning RTRW has already paid attention on the synergy with the surrounding regions Inter-Regional Context a map overlay was conducted followed by analysis of verbal logic. To determine the performance of the regional development a Principal Components Analysis PCA was done. The analysis results showed that inconsistencies in the spatial planning had caused a variety of problems that resulted in decreased performance of the regional development. The main problems that should receive more attention are infrastructure development growth economic growth transportation aspect and new properties.

  11. Preparation and Performance of Geopolymers

    Institute of Scientific and Technical Information of China (English)

    GUO Wenying; WU Guolin; WANG Jianda; WEN Ziyun; YIN Suhong

    2008-01-01

    The influence of each factor on the reaction of geopolymers material was investigated by using the orthogonal experimental design method, which got the optimal condition of reaction. Based on this results the performances of geopolymers were investigated. The results are as follows: (1) The effect of each factor on the compressive strength of geopolymers was different; (2) For paste the optimal condition of reaction is that the modulus and the concentration of sodium silicate solution are 1.2 and 40%, the calcined temperature and calcined time of kaolin are 800℃ and 2h, and the liquid-solid ratio is 1.25; (3) When the pH value of solution is higher than 1, the compressive strength of Geopolymers will not decrease as that in the water; (4) As the calcined temperature of samples were lower than 700℃ the heat-resistant of geopolymers was good; (5) Geopolymers is unlikely to react with the active aggregate.

  12. Paying health workers for performance in Battagram district, Pakistan

    Directory of Open Access Journals (Sweden)

    Javeed Sarah

    2011-10-01

    Full Text Available Abstract Background There is a growing interest in using pay-for-performance mechanisms in low and middle-income countries in order to improve the performance of health care providers. However, at present there is a dearth of independent evaluations of such approaches which can guide understanding of their potential and risks in differing contexts. This article presents the results of an evaluation of a project managed by an international non-governmental organisation in one district of Pakistan. It aims to contribute to learning about the design and implementation of pay-for-performance systems and their impact on health worker motivation. Methods Quantitative analysis was conducted of health management information system (HMIS data, financial records, and project documents covering the period 2007-2010. Key informant interviews were carried out with stakeholders at all levels. At facility level, in-depth interviews were held, as were focus group discussions with staff and community members. Results The wider project in Battagram had contributed to rebuilding district health services at a cost of less than US$4.5 per capita and achieved growth in outputs. Staff, managers and clients were appreciative of the gains in availability and quality of services. However, the role that the performance-based incentive (PBI component played was less clear--PBI formed a relatively small component of pay, and did not increase in line with outputs. There was little evidence from interviews and data that the conditional element of the PBIs influenced behaviour. They were appreciated as a top-up to pay, but remained low in relative terms, and only slightly and indirectly related to individual performance. Moreover, they were implemented independently of the wider health system and presented a clear challenge for longer term integration and sustainability. Conclusions Challenges for performance-based pay approaches include the balance of rewarding individual

  13. Reach preparation enhances visual performance and appearance.

    Science.gov (United States)

    Rolfs, Martin; Lawrence, Bonnie M; Carrasco, Marisa

    2013-10-19

    We investigated the impact of the preparation of reach movements on visual perception by simultaneously quantifying both an objective measure of visual sensitivity and the subjective experience of apparent contrast. Using a two-by-two alternative forced choice task, observers compared the orientation (clockwise or counterclockwise) and the contrast (higher or lower) of a Standard Gabor and a Test Gabor, the latter of which was presented during reach preparation, at the reach target location or the opposite location. Discrimination performance was better overall at the reach target than at the opposite location. Perceived contrast increased continuously at the target relative to the opposite location during reach preparation, that is, after the onset of the cue indicating the reach target. The finding that performance and appearance do not evolve in parallel during reach preparation points to a distinction with saccade preparation, for which we have shown previously there is a parallel temporal evolution of performance and appearance. Yet akin to saccade preparation, this study reveals that overall reach preparation enhances both visual performance and appearance.

  14. Postbaccalaureate Preparation and Performance in Medical School.

    Science.gov (United States)

    Hojat, Mohammadreza; And Others

    1990-01-01

    A study was conducted of 610 medical students to determine whether postbaccalaureate preparation before matriculation in medical school effected student performance. Results showed lower achievement on some measures of performance in medical school by those who had taken nondegree postbaccalaureate courses. Implications for admission decisions are…

  15. District Heating Systems Performance Analyses. Heat Energy Tariff

    Science.gov (United States)

    Ziemele, Jelena; Vigants, Girts; Vitolins, Valdis; Blumberga, Dagnija; Veidenbergs, Ivars

    2014-12-01

    The paper addresses an important element of the European energy sector: the evaluation of district heating (DH) system operations from the standpoint of increasing energy efficiency and increasing the use of renewable energy resources. This has been done by developing a new methodology for the evaluation of the heat tariff. The paper presents an algorithm of this methodology, which includes not only a data base and calculation equation systems, but also an integrated multi-criteria analysis module using MADM/MCDM (Multi-Attribute Decision Making / Multi-Criteria Decision Making) based on TOPSIS (Technique for Order Performance by Similarity to Ideal Solution). The results of the multi-criteria analysis are used to set the tariff benchmarks. The evaluation methodology has been tested for Latvian heat tariffs, and the obtained results show that only half of heating companies reach a benchmark value equal to 0.5 for the efficiency closeness to the ideal solution indicator. This means that the proposed evaluation methodology would not only allow companies to determine how they perform with regard to the proposed benchmark, but also to identify their need to restructure so that they may reach the level of a low-carbon business.

  16. Measuring the job performance of district health managers in Latin America.

    Science.gov (United States)

    Díaz-Monsalve, S J

    2003-04-01

    In resource-poor countries, district health managers (DHM) have gained importance as health systems have become decentralized. Although the roles and key functions of DHM have been described in the literature, there appears to have been no analysis of what they are really doing. In this context, the knowledge and job performance of 218 DHM from nine Latin American countries were investigated. The study was based on 12 performance indicators, two self-administered questionnaires (which included internal consistency tests), formal and informal, check interviews in the work place, and direct observations of the DHM. The DHM investigated were found to be particularly weak in systems management (community involvement and intersectoral co-operation), monitoring activities and the systematic organization of meetings. They were rarely involved in the identification of priority health problems or of high-risk groups, and failed to use health-service indicators sufficiently for the analysis of the district health system. The managers were stronger in relation to the organization of technical meetings and the development and implementation of local health plans. Factors associated with good management performance were a favourable organizational structure (including written job descriptions and support from the authorities), 'decision power' (i.e. the ability to select and appoint new staff ) and a good knowledge of the local situation. In Latin America, at least, DHM need to be better prepared, supervised and supported.

  17. The Development and Evaluation of Criteria for Performance Contracting by Consultants to School Districts.

    Science.gov (United States)

    Champagne, David W.; Morgan, John L.

    The process of performance contracting by consultants to a school district is presented. Beginning with a proposal for A Training Program for Instructional Specialists--East-Northern School District, the next step is The Supervisory Conference, which is followed by Performance Contract Specifications. A checklist is then provided for Assessment of…

  18. Social Capital Development within a Novice District-Grown Principal Preparation Program: A Case Study of the DCPS Patterson Fellowship

    Science.gov (United States)

    Hansen, Allison

    2016-01-01

    In the last decade district-managed principal preparation programs have become common as a means for school leadership preparation (Leithwood, Seashore-Lewis, Anderson, & Wahlstrom, 2004; Turnbull, Riley, & MacFarlane, 2015), but evaluations of these programs are relatively rare. This dissertation evaluates one such program, the Mary Jane…

  19. The Relationship between Student Transfers and District Academic Performance: Accounting for Feedback Effects

    Science.gov (United States)

    Welsch, David M.; Zimmer, David M.

    2015-01-01

    This paper draws attention to a subtle, but concerning, empirical challenge common in panel data models that seek to estimate the relationship between student transfers and district academic performance. Specifically, if such models have a dynamic element, and if the estimator controls for unobserved traits by including district-level effects,…

  20. Do district health systems perform differently because of their managers? Preliminary insights from Indonesia

    Directory of Open Access Journals (Sweden)

    Augustine Asante

    2015-07-01

    Full Text Available District health systems (DHS are central to the global efforts to improve health outcomes but many remain ineffective. In many lowresource settings, despite the generally weak DHS there is evidence that some districts consistently perform well against the odds, and this is often attributed to the calibre of managers leading such districts and their management and leadership (M&L skills. This paper examines the M&L practices of district health managers in high and low performing districts in Indonesia in an attempt to understand whether the differences in the performance of DHS can be explained, at least in part, by the differences in the performance of their health managers. We employed a mixed methods case study design focusing on two purposefully selected districts. Data were collected in 2011 using questionnaires and in-depth interviews. The preliminary results suggest that M&L practices of managers in the high and low performing districts are similar and provide little explanation for the differences in the performance of the two DHS. Contextual and health system factors offered a much better explanation for the variations in DHS performance.

  1. Ethnoveterinary medicinal plants: Preparation and application methods by traditional healers in selected districts of southern Ethiopia

    Directory of Open Access Journals (Sweden)

    Gebremedhin Romha Eshetu

    2015-05-01

    Full Text Available Aim: The aim was to document the ethnoveterinary medicinal plants, their preparation, and application methods used by traditional healers in treating different animal diseases, in four districts with different culture and languages in southern Ethiopia. Materials and Methods: Information of ethnoveterinary medicinal plants was obtained through in-depth direct interview with the local healers and field observations. A descriptive statistics was used to analyze the reported ethnoveterinary medicinal plants and associated indigenous knowledge. The informant consensus factor (ICF was calculated for each category of diseases to identify the agreements of the informants on the reported cures. Preference ranking was used to assess the degree of effectiveness of certain medicinal plants against most prevalent animal diseases in the area. Results: The healers had a very high intention to keep their traditional knowledge secrete and none of them was ready to transfer their knowledge either freely or on incentive bases to other people; they need to convey their knowledge only to their selected scions after getting very old. A total of 49 plant species used to treat 26 animal ailments were botanically classified and distributed into 34 families. The most commonly used plant parts for remedy preparations were leaves (38.8%, followed by whole roots (20.4%. Calpurnia aurea (Ait. Benth was the most preferred effective treatment against external parasite and skin problem, which is the most prevalent disease with the highest ICF (0.68. Conclusion: The study suggests that the community of the study districts depend largely on ethnoveterinary medicinal plants for the treatment of different animal ailments though the healers have a very high intention to keep their traditional knowledge secrete. Commonly reported plant species need to be tested for their antimicrobial activities in vitro and validated their active ingredients in order to recommend effective

  2. Preparing to perform: periodization and dance.

    Science.gov (United States)

    Wyon, Matthew

    2010-01-01

    This article reviews the historical and current literature on periodization in sport before applying the concept to dance from scientific and anecdotal points of view. Preparing the dancer through the use of a periodization model, in a professional or vocational setting, will potentially help prevent overtraining and its link to injury, while improving the dancer's readiness to perform optimally. Practical examples of tapering and periodization of training are discussed for companies and vocational schools.

  3. Preparing to perform an awake fiberoptic intubation.

    LENUS (Irish Health Repository)

    Walsh, M E

    2012-02-03

    Fiberoptically guided tracheal intubation represents one of the most important advances in airway management to occur in the past thirty years. Perhaps its most important role is in management of the anticipated difficult airway. This is a situation in which the dangers of encountering the life-threatening "can\\'t intubate, can\\'t ventilate" situation can be avoided by placement of an endotracheal tube while the patient is awake. Although skill at the procedure of endoscopy is obviously necessary in this setting, these authors hold that success or failure of the technique frequently depends on the adequacy of preparation. These measures include 1) pre-operative assessment of the patient; 2) careful explanation of what lies in store; 3) "setting the stage"; 4) preparing the equipment to be used; and 5) preparing the patient (antisialogue, sedation, application of topical anesthesia to the upper airway). If these preparatory measures are carried out meticulously, the likelihood of performing a successful and comfortable awake fiberoptic tracheal intubation is greatly increased.

  4. A Partnership between the Dallas County Community College District and Texas Instruments: Using Total Quality Management to Reinvent Workforce Preparation.

    Science.gov (United States)

    Wenrich, J. William

    1994-01-01

    Describes elements of a partnership between Dallas County Community College District and Texas Instruments that draws on the concepts and processes of Total Quality Management (TQM). Suggests that such partnerships have the net effect of significantly improving and reinventing cooperative efforts to prepare students for the workforce. (MAB)

  5. Lessons from Country Borders: Preparing Leaders for Social Justice and Diversity through a District and University Partnership

    Science.gov (United States)

    Murakami Ramalho, Elizabeth; Garza, Encarnacion, Jr.; Merchant, Betty

    2009-01-01

    The purpose of this study was to explore the preparation of educators as school leaders in a master's degree program focused on diversity and social justice. This program is a partnership between the University of Texas at San Antonio and the San Antonio Independent School District. The program's proximity to the Mexican border provides an…

  6. Evaluations of different domestic hot water preparing methods with ultra-low-temperature district heating

    DEFF Research Database (Denmark)

    Yang, Xiaochen; Li, Hongwei; Svendsen, Svend

    2016-01-01

    of Legionella in the DHW (domestic hot water) and assure the comfortable temperature, all substations were installed with supplementary heating devices. Detailed measurements were taken in the substations, including the electricity demand of the supplementary heating devices. To compare the energy and economic...... performance of the substations, separate models were built based on standard assumptions. The relative heat and electricity delivered for preparing DHW were calculated. The results showed that substations with storage tanks and heat pumps have high relative electricity demand, which leads to higher integrated...... costs considering both heat and electricity for DHW preparation. The substations with in-line electric heaters have low relative electricity usage because very little heat is lost due to the instantaneous DHW preparation. Accordingly, the substations with in-line electric heaters would have the lowest...

  7. Health system performance at the district level in Indonesia after decentralization

    Directory of Open Access Journals (Sweden)

    Choi Yoonjoung

    2010-03-01

    Full Text Available Abstract Background Assessments over the last two decades have showed an overall low level of performance of the health system in Indonesia with wide variation between districts. The reasons advanced for these low levels of performance include the low level of public funding for health and the lack of discretion for health system managers at the district level. When, in 2001, Indonesia implemented a radical decentralization and significantly increased the central transfer of funds to district governments it was widely expected that the performance of the health system would improve. This paper assesses the extent to which the performance of the health system has improved since decentralization. Methods We measured a set of indicators relevant to assessing changes in performance of the health system between two surveys in three areas: utilization of maternal antenatal and delivery care; immunization coverage; and contraceptive source and use. We also measured respondents' demographic characteristics and their living circumstances. These measurements were made in population-based surveys in 10 districts in 2002-03 and repeated in 2007 in the same 10 districts using the same instruments and sampling methods. Results The dominant providers of maternal and child health in these 10 districts are in the private sector. There was a significant decrease in birth deliveries at home, and a corresponding increase in deliveries in health facilities in 5 of the 10 districts, largely due to increased use of private facilities with little change in the already low use of public facilities. Overall, there was no improvement in vaccination of mothers and their children. Of those using modern contraceptive methods, the majority obtained them from the private sector in all districts. Conclusions There has been little improvement in the performance of the health system since decentralization occurred in 2001 even though there have also been significant increases in

  8. The Impact of a District Assistant Principal Leadership Preparation Program on Perceptions of Effective Leadership Behaviors

    Science.gov (United States)

    Markham, Ruth

    2013-01-01

    A large, urban school district in the southeastern region of the United States found that leaders supplied by universities lacked skills needed to meet its accountability challenges. Because the school district demands highly effective leaders for its growing schools, an Aspiring Leader Program (ALP) was established to train its future assistant…

  9. The Problem: Low-Achieving Districts and Low-Performing Boards

    Directory of Open Access Journals (Sweden)

    David E. Lee

    2014-10-01

    Full Text Available Effective school districts maintain superintendent and school board collegiality which can foster success and connectedness among members. Delagardelle and Alsbury (2008 found that superintendents and board members are not consistent in their perceptions about the work the board does, and Glass (2007 found that states do not require boards to undergo evaluation for effectiveness. In the current study, 115 board meetings were observed using the School Board Video Project (SBVP survey, which was created in 2012 by researchers to uncover school board meetings’ effectiveness. MANOVA, Univariate ANOVA, and Pearson Chi-Square test results revealed significant differences between low-, medium-, and high-performing districts’ school board meetings. Evidence indicated that low-performing districts’ board meetings were: less orderly; had less time spent on student achievement; lacked respectful and attentive engagement across speakers; had board meeting members who seemed to advance their own agenda; had less effective working relationships among the governance team; had fewer board members who relied on the superintendent for advice and input; had one member, other than the board president, stand out for taking excessive time during meetings; and did not focus on policy items as much as high- and medium-performing school districts. The research concluded that more school board members from low-performing districts needed training to improve their effectiveness. Furthermore, highly refined and target-enhanced school board training programs might lead to lasting governance success and more effective teaming that could improve district, and ultimately, student achievement.

  10. Managing School Districts for High Performance: Cases in Public Education Leadership

    Science.gov (United States)

    Childress, Stacey, Ed.; Elmore, Richard F., Ed.; Grossman, Allen, Ed.; Johnson, Susan Moore, Ed.

    2007-01-01

    "Managing School Districts for High Performance" brings together more than twenty case studies and other readings that offer a powerful and transformative approach to advancing and sustaining the work of school improvement. At the center of this work is the concept of organizational coherence: aligning organizational design, human…

  11. Performance of low-temperature district heating for low-energy houses

    DEFF Research Database (Denmark)

    Brand, Marek; Dalla Rosa, Alessandro; Svendsen, Svend

    2010-01-01

    houses, which was previously developed and reported in the project “Development and demonstration of low-energy district heating for low energy housing” [EFP, 2007]. Two different concepts of low energy district heating substations are tested, and measurements of their performance aim to document...... that LEDH is a proper solution for sustainable heating systems and answer the question which concept of used substations is more favourable to be used in detached low energy houses. The preliminary results show that LEDH can provide low energy buildings with space heating and domestic hot water (DHW...

  12. A Guide to Calculating District Expenditure-to-Performance Ratios Using Publicly Available Data. REL 2017-179

    Science.gov (United States)

    Ryan, Sarah; Lavigne, Heather J.; Zweig, Jacqueline S.; Buffington, Pamela J.

    2017-01-01

    Districts across the nation are seeking ways to increase efficiency by maintaining, if not improving, educational outcomes using fewer resources. One measure that is sometimes used as a proxy for school district efficiency is an expenditure-to-performance ratio, for example a ratio of per pupil expenditures to student academic performance. This…

  13. Evaluation of the impact of child care on the academic performance of elementary school students in Kermanshah District

    Directory of Open Access Journals (Sweden)

    Hassan Abdi

    2014-06-01

    Full Text Available The preschool serious and sensitive issue is not as simple as it passed. In early childhood education, a wide range of interest, has been involved in education. This study, based on an analytical method - a description, and utilization of resources in these fields, as well as a library of methods and a questionnaire to assess the impact of preschool education on the academic performance of first-grade students in Kermanshah district, are discussed. The results imply that, between general information and academic performance Kermanshah district, there is a significant relationship. Between then herd behavior, and academic performance of students in Kermanshah district, according to the results obtained, there is no significant relationship. Between the questions and answers in class, and academic performance of students Kermanshah district, and between the total scores of academic knowledge and academic performance of students in Kermanshah district, there is a significant relationship.

  14. The Relationship between Schools' Costs per Pupil and Nevada School Performance Framework Index Scores in Clark County School District

    Science.gov (United States)

    Rice, John; Huang, Min

    2015-01-01

    Clark County School District (CCSD) asked the Western Regional Education Laboratory (REL West) to examine the relationship between spending per pupil and Nevada School Performance Framework (NSPF) index scores in the district's schools. Data were examined from three school years (2011/12, 2012/13, 2013/14) and for three types of schools…

  15. Student USMLE Step One Preparation and Performance.

    Science.gov (United States)

    Zhang, Chi

    This study investigated factors associated with medical students performance on the United States Medical Licensing Examination (USMLE) Step One examination. The USMLE Step One emphasizes basic mechanisms and principles that are typically covered in the first 2 years of medical school. The study examined the relationship among student performance…

  16. Teaching Teams about Teamwork: Preparation, Practice, and Performance Review

    Science.gov (United States)

    Snyder, Lisa Gueldenzoph

    2009-01-01

    Focusing on preparation, practice, and performance review to teach teams about teamwork provides a well-supported and effective methodology that both enhances students' collaborative skills and contributes to an effective team project experience. Preparation includes aspects of coaching to introduce and explain effective group processes. After…

  17. Performance Analysis of a Hybrid District Heating System: a Case Study of a Small Town in Croatia

    Directory of Open Access Journals (Sweden)

    Robert Mikulandric

    2015-09-01

    Full Text Available Hybridisation of district heating systems can contribute to more efficient heat generation through cogeneration power plants or through the share increase of renewable energy sources in total energy consumption while reducing negative aspects of particular energy source utilisation. In this work, the performance of a hybrid district energy system for a small town in Croatia has been analysed. Mathematical model for process analysis and optimisation algorithm for optimal system configuration has been developed and described. The main goal of the system optimisation is to reduce heat production costs. Several energy sources for heat production have been considered in 8 different simulation cases. Simulation results show that the heat production costs could be reduced with introduction of different energy systems into an existing district heating system. Renewable energy based district heating systems could contribute to heat production costs decrease in district heating systems up to 30% in comparison with highly efficient heat production technologies based on conventional fuels.

  18. Performance of district disaster management teams after undergoing an operational level planners' training in Uganda.

    Science.gov (United States)

    Orach, Christopher Garimol; Mayega, Roy William; Woboya, Vincent; William, Bazeyo

    2013-06-01

    Uganda is vulnerable to several natural, man-made and a hybrid of disasters including drought, famine, floods, warfare, and disease outbreaks. We assessed the district disaster team's performance, roles and experiences following the training. The disasters most commonly experienced by the district teams were epidemics of diseases in humans (7 of 12), animals (epizoonotics) (3 of 12) and crops (3 of 12); hailstorms and floods (3 of 12). The capabilities viewed most useful for management of disasters were provision of health care services (9/12) and response management (8 of 12). The capability domains most often consulted during the disasters were general response management (31%), health services (29%) and water and sanitation (17%). The skills areas perceived to be vital following the training were response to epidemics 10/12, disaster management planning 8/12, hazards and vulnerability analysis 7/12 and principles of disaster planning 7/12 respectively. Main challenges mentioned by district teams were inadequacy of finance and logistics, lack of commitment by key partners towards disaster preparedness and response. The most common disaster experienced disasters related to outbreaks of diseases in man, animals and crops. The most frequently applied capabilities were response management and provision of emergency health services. The activities most frequently implemented following disaster management teams training were conducting planning meetings, refinement of plans and dissemination of skills gained. The main challenges were related to limited budget allocations and legal frameworks for disaster management that should be addressed by both central and local governments.

  19. Lowering district heating temperatures – Impact to system performance in current and future Danish energy scenarios

    DEFF Research Database (Denmark)

    Ommen, Torben; Markussen, Wiebke Brix; Elmegaard, Brian

    2016-01-01

    CHP (Combined heat and power) production in connection with DH (district heating) systems has previously demonstrated a significant reduction in primary energy consumption. With extended installation of intermittent sustainable sources, such as eg. wind turbines rather than thermal units....... Utility plants and demand curves corresponded to the current and future scenarios for the DH system of Greater Copenhagen. Performance curves from typical CHP-plant technologies were used to represent the changed operation of power and heat production for changed DH temperatures. The results show...

  20. Preparing for Memorized Cello Performance: The Role of Performance Cues

    Science.gov (United States)

    Chaffin, Roger; Lisboa, Tania; Logan, Topher; Begosh, Kristen T.

    2010-01-01

    An experienced cello soloist recorded her practice as she learned and memorized the Prelude from J.S. Bach's Suite No. 6 for solo cello and gave 10 public performances over a period of more than three years. She described the musical structure, decisions about basic technique (e.g., bowing), interpretation (e.g., dynamics), and five kinds of…

  1. Technical, economic and environmental investigation of using district heating to prepare domestic hot water in Chinese multi-storey buildings

    DEFF Research Database (Denmark)

    Zhang, Lipeng; Xia, Jianjun; Thorsen, Jan Eric;

    2016-01-01

    utilizes the industrial waste heat to prepare DHW via the DH network. A building model of a multi-storey building in Beijing was developed to investigate the technical feasibility. An economic evaluation was made using net present value to compare the annualized cost for individual water heaters and flat......The development of DH (District Heating) is an environmentally friendly and energy-efficient strategy in China. Currently, the vast majority of DH systems are SH (Space Heating) only and do not provide DHW (Domestic Hot Water). DHW is mainly produced by individual water heaters due to the cost......-effective issues of the centralized DHW systems. From the perspective of long-term development, DHW produced via DH systems would be more sustainable because DH is an important precondition for an environmental safe use of domestic waste fuels. This paper presents an approach that uses flat stations meanwhile...

  2. Psychological Preparation for Peak Performance in Sports Competition

    Science.gov (United States)

    Ohuruogu, Ben; Jonathan, Ugwuanyi I.; Ikechukwu, Ugwu Jude

    2016-01-01

    This paper attempts to make an overview of various techniques, sport psychologist adopt in psychological preparation of athletes for peak performance. To attain peak performance in sports competitions, coaches and athletes should not base their prospect on physical training on sport skills alone rather should integrate both the mental and physical…

  3. Practicing perfection: How concert soloists prepare for performance

    OpenAIRE

    Roger Chaffin; Topher Logan

    2006-01-01

    Musical performances by concert soloists in the Western classical tradition are normally memorized. For memory to work reliably under the pressures of the concert stage, the performance must be practiced until it is thoroughly automatic. At the same time, the performance must be fresh and spontaneous in order to communicate emotionally with the audience. The resolution of this apparent contradiction is provided by longitudinal case studies of concert soloists preparing new works for performan...

  4. The Effect Of Working Environment Compensation And Working Ethos Towards Employee Performance On Mariso Districts Office In Makassar

    Directory of Open Access Journals (Sweden)

    Rismawati

    2015-08-01

    Full Text Available The influence of the working environment Compensation and Employee Performance Against Work Ethics In Makassar Mariso District Office. The purpose of this study was to determine the effect of the work environment Compensation and Employee Performance Against Working Ethos In Makassar Mariso District Office. The population in this study is Mariso District Office employee In Makassar with a sample size of 70 people. Methods of data collection in this study is a questionnaire interview and documentation. Methods of data analysis using descriptive and quantitative methods namely the multiple linear regression analysis were used to measure the Effect of Work environment Working Ethos Against Compensation and Employee Performance In Makassar Mariso District Office. Based on the F test of independent variables Work Environment Compensation and Working Ethos jointly have the positive and significant effect on the dependent variable employee performance. Through testing the correlation coefficient R was obtained that the degree of correlation or relationship between Work Environment Working Ethos Against Compensation and employee performance is a high correlation is 77.0. And work ethic is the most dominant factor affecting Employee Performance In Makassar Mariso District Office.

  5. Optimization of a local district heating plant under fuel flexibility and performance

    DEFF Research Database (Denmark)

    Rudra, Souman; Rosendahl, Lasse; From, Niels

    2011-01-01

    Brovst is a small district in Denmark. Based on the case of Brovst, this paper analyses the role of district heating in future Renewable Energy Systems. The present use of fossil fuels in the Brovst DHP (district heating plant) represents an increasing environmental and climate-related load. So, ...

  6. The Level of Diagnostic Tests' Preparation Skills among the Teachers of the First Three Elementary Grades' Teachers at the Directorate of Education of Bani Kinana District

    Science.gov (United States)

    Yaghmour, Kholoud Subhi; Obaidat, Luai Taleb; Hamadneh, Qaseem Mohammad

    2016-01-01

    This study aimed at exploring the level of Diagnostic Tests' Preparation Skills among the teachers of the first Three Elementary Grades at the Directorate of Education of Bani Kinana District, and its relationship to the variables of gender, academic qualification, and years of experience. The sample of the study consisted of (264) male and female…

  7. Enriching the Preparation of Education Researchers and Practitioner-Scholars: Linking School District Research Priorities and University-Based Policy Evaluation Research Courses

    Science.gov (United States)

    Malen, Betty

    2017-01-01

    This article analyzes a novel effort to strengthen the preparation of both practitioner-scholars and education researchers. It describes a university-district partnership that offers graduate students the opportunity to develop research understandings and skills through participation in a "real" research project and provides district…

  8. Statewide Writing Assessment Follow-Up; Federal Reporting Requirements; Preparing the School District Assessment Portfolio. Update # 5. STARS: School-Based Teacher-Led Assessment and Reporting System.

    Science.gov (United States)

    Nebraska State Dept. of Education, Lincoln.

    This update provides information about the Nebraska Statewide Writing Assessment follow-up, the federal reporting of assessment information, and preparing the school District Assessment Portfolio. The information is intended to assist local educators in the reporting of local assessment information in June 2001. The update on the writing…

  9. Facility type and primary care performance in sub-district health promotion hospitals in Northern Thailand.

    Science.gov (United States)

    Kitreerawutiwong, Nithra; Jordan, Sue; Hughes, David

    2017-01-01

    Poor and middle-income Thai people rely heavily on primary care health services. These are staffed by a range of professionals. However, it is unknown whether the performance of primary care varies according to the staffing and organization of local service delivery units. Tambon (sub-district) health promotion hospitals (THPHs) were introduced in 2009 to upgrade the services offered by the previous health centres, but were faced with continuing shortages of doctors and nurses. The Ministry of Public Health (MoPH) designated three categories of THPH, defined according to whether they were regularly staffed by a medical practitioner, a qualified nurse or non-clinical public health officers. This study aimed to compare the performance of primary care offered by the three different types of primary care facilities in one public health region of Northern Thailand (Public Health Region 2). A cross-sectional survey was undertaken in 2013. Data were collected on accessibility, continuity, comprehensiveness, co-ordination and community orientation of care from 825 patients attending 23 primary care facilities. These were selected to include the three officially-designated types of Tambon (sub-district) health promotion hospitals (THPHs) led by medical, nursing or public health personnel. Survey scores were compared in unadjusted and adjusted analyses. THPHs staffed only by public health officers achieved the highest performance score (Mean = 85.14, SD. = 7.30), followed by THPHs staffed by qualified nurses (Mean = 82.86, SD. = 7.06). THPHs staffed by a doctor on rotation returned the lowest scores (Mean = 81.63, SD. = 7.22). Differences in overall scores resulted mainly from differences in reported accessibility, continuity, and comprehensiveness of care, rather than staff skill-mix per se. Policy on quality improvement should therefore focus on improving performance in these areas.

  10. Facility type and primary care performance in sub-district health promotion hospitals in Northern Thailand

    Science.gov (United States)

    Kitreerawutiwong, Nithra; Jordan, Sue; Hughes, David

    2017-01-01

    Background Poor and middle-income Thai people rely heavily on primary care health services. These are staffed by a range of professionals. However, it is unknown whether the performance of primary care varies according to the staffing and organization of local service delivery units. Tambon (sub-district) health promotion hospitals (THPHs) were introduced in 2009 to upgrade the services offered by the previous health centres, but were faced with continuing shortages of doctors and nurses. The Ministry of Public Health (MoPH) designated three categories of THPH, defined according to whether they were regularly staffed by a medical practitioner, a qualified nurse or non-clinical public health officers. This study aimed to compare the performance of primary care offered by the three different types of primary care facilities in one public health region of Northern Thailand (Public Health Region 2). Methods A cross-sectional survey was undertaken in 2013. Data were collected on accessibility, continuity, comprehensiveness, co-ordination and community orientation of care from 825 patients attending 23 primary care facilities. These were selected to include the three officially-designated types of Tambon (sub-district) health promotion hospitals (THPHs) led by medical, nursing or public health personnel. Survey scores were compared in unadjusted and adjusted analyses. Results THPHs staffed only by public health officers achieved the highest performance score (Mean = 85.14, SD. = 7.30), followed by THPHs staffed by qualified nurses (Mean = 82.86, SD. = 7.06). THPHs staffed by a doctor on rotation returned the lowest scores (Mean = 81.63, SD. = 7.22). Conclusions Differences in overall scores resulted mainly from differences in reported accessibility, continuity, and comprehensiveness of care, rather than staff skill-mix per se. Policy on quality improvement should therefore focus on improving performance in these areas. PMID:28339494

  11. Data Preparation Process for the Buildings Performance Database

    Energy Technology Data Exchange (ETDEWEB)

    Walter, Travis; Dunn, Laurel; Mercado, Andrea; Brown, Richard E.; Mathew, Paul

    2014-06-30

    The Buildings Performance Database (BPD) includes empirically measured data from a variety of data sources with varying degrees of data quality and data availability. The purpose of the data preparation process is to maintain data quality within the database and to ensure that all database entries have sufficient data for meaningful analysis and for the database API. Data preparation is a systematic process of mapping data into the Building Energy Data Exchange Specification (BEDES), cleansing data using a set of criteria and rules of thumb, and deriving values such as energy totals and dominant asset types. The data preparation process takes the most amount of effort and time therefore most of the cleansing process has been automated. The process also needs to adapt as more data is contributed to the BPD and as building technologies over time. The data preparation process is an essential step between data contributed by providers and data published to the public in the BPD.

  12. STRATEGIC MANAGEMENT TOOLS, STAKEHOLDERS AND PERFORMANCE ORGANIZATIONS, PRIVATE HEALTH BRANCH OF THE FEDERAL DISTRICT

    Directory of Open Access Journals (Sweden)

    Bruno Vendruscolo

    2012-06-01

    Full Text Available This study aimed to identify the use of management tools and the influence of stakeholders on organizational performance of companies in the private health sector in the Federal District. We used the tools of strategic management, such as budgeting, strategic planning, balanced scorecard, benchmarking, and management software. Study participants consist of individuals involved in strategic processes. We analyzed the past 5 years in organizations to understand the performance. The data collection was face-to-face, the instruments consisted of qualitative interviews in person, and semi-structured content analysis. We also performed analysis of secondary data and documents. To measure the performance between the organizations we used the method of data envelopment analysis (DEA, using the CCR standard, and the mean change index as the number of employees, physicians, costs, number of appointments, and tests. In the analysis of tools and stakeholders we adapted values for the major and minor influences and the other results found framed. The results cite the presence of management tools in five of the six organizations. The comparison of performance between them presented as a result that organizations 2 and 4 were efficient and 3 was the least efficient. The study identified the need to understand the requirements of stakeholders and the indicators set out to understand organizational performance and its evolution, mainly determined by the management tools. Although not reaching proposed levels, this work creates hypotheses about the use of these tools and analysis of stakeholders in organizational performance.

  13. Exergy performance analysis of the conceptual district energy network system with heat pump

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Seung Won; Chung, Ha Seung [Hongik University, Seoul (Korea, Republic of); Kim, Min Sung [Korea Institute of Energy Research, Daejeon (Korea, Republic of)

    2014-08-15

    To increase the efficiency of a district heating system, we propose a district energy network concept which combines several heating resources with additional electric heat pump and thermal energy storage. With help of thermal energy storage, a heat pump can be operated at maximum efficiency at all the time. Electricity generated with less CO{sub 2} emission makes the proposed system much more environmentally friendly. Even though the proposed concept can be applied to any given situation, a specific target area was chosen to show the effectiveness of the newly proposed energy network concept more clearly. Several constraints were applied for the selection process and a simplified model used for quantitative comparison between the existing and the developed concept. Exergy analysis showed the increased performance of proposed energy network system. The result showed that the newly proposed concept generates less CO{sub 2} emission by 46% at maximum compared to the existing system. By using additional renewable energy sources, we can reduce CO{sub 2} emission even further.

  14. Environmental performance of Miscanthus as a fuel alternative for district heat production

    DEFF Research Database (Denmark)

    Parajuli, Ranjan; Sperling, K.; Dalgaard, Tommy

    2015-01-01

    scenarios: (i) in Combined Heat and Power (CHP) plant and (ii) in a Boiler (producing heat only). Biomass conversion to heat is also compared with the conversion of natural gas (NG). The environmental impact categories considered for the assessment are: Global Warming Potential (GWP), Non-Renewable Energy......This study discusses about the environmental performance of Miscanthus conversion to district heat. Life Cycle Impact Assessment (LCIA) is used as a tool to assess the environmental impacts related to the biomass conversion to heat. Energy conversion of Miscanthus is compared in two combustion...... that despite the biomass possessed advantage in reducing GWP and NRE use, additional land required for Miscanthus could be seen as a disadvantage....

  15. Role Performance of Community Health Volunteers and Its Associated Factors in Kuching District, Sarawak

    Directory of Open Access Journals (Sweden)

    Melvin Hsien Liang Chung

    2017-01-01

    Full Text Available The objective of this study was to assess the role performance among KOSPEN community health volunteer in Kuching district and its associated factors. This was a cross-sectional study, conducted in 21 localities in Kuching with a total of 210 respondents. Data were collected using validated interviewer-administered questionnaires and analyzed using SPSS version 22.0. The respondents comprised 55.2% females, 81.9% married, and 41.4% aged above 45 and above and 72.4% completed their education up to secondary school. The result revealed that 59.0% of the respondents agreed and understood their role performances. Multiple Logistics analysis revealed that factors associated with role performance were age group (p=0.003, education level (p<0.001, marital status (p=0.025, prestige and respect (p=0.012, being seen as “doctor” in community (p=0.003, job aids (p=0.009, training location (p=0.001, and supervision by community (p<0.001. To increase and maintain the work performance of CHVs, commitment from the government, policy makers, stakeholders, and the communities is required.

  16. Techno-economic analysis of a local district heating plant under fuel flexibility and performance

    DEFF Research Database (Denmark)

    Rudra, Souman; Rosendahl, Lasse

    2017-01-01

    Brovst is a small district in Denmark. This paper analyses the use of local renewable resources in the district heating systems of Brovst. The present use of fossil fuels in the Brovst district heating plant (DHP) represents an increasing environmental and climate-related load. Therefore, an inve......Brovst is a small district in Denmark. This paper analyses the use of local renewable resources in the district heating systems of Brovst. The present use of fossil fuels in the Brovst district heating plant (DHP) represents an increasing environmental and climate-related load. Therefore......, an investigation has been made to reduce the use of fossil fuels for district heating system and make use of the local renewable resources (biogas, solar, and heat pump) for district heating purposes. In this article, the techno-economic assessment is achieved through the development of a suite of models......PRO, which has been used to analyze the integration of a large-scale energy system into the domestic district heating system. A model of the current work on the basis of information from the Brovst plant (using fossil fuel) is established and named as a reference option. Then, four other options...

  17. Knowledge and work performance of multi-purpose workers under national leprosy eradication programme in Satara district, Maharashtra.

    Science.gov (United States)

    Mohite, R V; Mohite, V R

    2012-01-01

    After integration of leprosy services into general health care services, peripheral health care workers played important role in leprosy elimination. The objectives of present study are to assess the knowledge and work performance of multi-purpose workers and it's correlation towards eradication of leprosy under national leprosy eradication programme in Satara district. The cross sectional study was conducted over a period of 6 months includes 71 Primary health centres (PHCs) and 6 Urban leprosy centres (ULCs) providing leprosy services to whole Satara district, Maharashtra. Random sampling technique was used to select study subjects (Multi-purpose workers, MPWs) and data was collected by using pre-tested semi structured proforma by personal interview method. Percentage distribution and statistical association between knowledge and work performance was analysed. More than 88.31% MPWs had good knowledge about leprosy and National leprosy eradication programme (NLEP), similarly more than 88.42% showed good work performance under NLEP in Satara district. Significant statistical association was existed between age and work experience of MPWs with their work performance under NLEP (chi2=11.2, p=0.023* and chi2=10.1, p=0.038*). Significant correlation was also observed between knowledge of MPWs about leprosy and NLEP with their work performance under NLEP (r=0.66, p=0.001*). Satara district achieved leprosy elimination which was mainly due to very good knowledge and quality work performance by multi-purpose workers.

  18. Pupil Home Background Characteristics and Academic Performance in Senior Secondary Schools: A Case Study of Selected Secondary Schools in Kitwe District, Zambia

    Science.gov (United States)

    Kakumbi, Zonic; Samuel, Elizabeth B.; Mulendema, Peter J.

    2016-01-01

    The purpose of this research was to investigate pupil background characteristics and academic performance in senior secondary schools in Kitwe district with a view of recommending on how to improve pupils' performance. The study was conducted in Kitwe district because in the past years pupils' performance in senior secondary schools has been…

  19. Cognitively Guided Instruction: An Implementation Case Study of a High Performing School District

    Science.gov (United States)

    Dowdy, William D. B.

    2011-01-01

    No Child Left Behind legislation developed goals for every student to be proficient in each academic subject by 2014. California's students are far from meeting this goal, especially in mathematics. One Southern Californian school district, renamed Green Valley Unified School District for anonymity, began using Cognitively Guided Instruction…

  20. How School Districts Can Support Deeper Learning: The Need for Performance Alignment. Deeper Learning Research Series

    Science.gov (United States)

    Honig, Meredith I.; Rainey, Lydia R.

    2015-01-01

    School district leaders nationwide aspire to help their schools become vibrant places for learning--where students have meaningful academic opportunities and develop critical thinking and problem-solving skills. Historically, though, school district central offices have been ill-equipped to support such ambitious goals. A new wave of research…

  1. Do Student Migrations Affect School Performance? Evidence from Wisconsin's Inter-District Public School Program

    Science.gov (United States)

    Welsch, David M.; Zimmer, David M.

    2012-01-01

    This paper examines the competitive effects of a unique school choice program implemented in the late 1990s, Wisconsin's open enrollment program, which allows families to send their children to schools outside their home district. In contrast to other school choice programs, districts not only face negative consequences from losing students and…

  2. Assessing the State of Servant Leadership, Teacher Morale, and Student Academic Performance Outcomes in a Florida Elementary School District

    Science.gov (United States)

    EL-Amin, Abdul

    2013-01-01

    This descriptive research study was conducted to determine the state of perceived teacher morale and student academic performance as measured by fourth-grade reading and math scores among four elementary schools defined by the servant leadership score of each principal in this Florida elementary school district. While related research from other…

  3. The Relationship between of Teacher Competence, Emotional Intelligence and Teacher Performance Madrasah Tsanawiyah at District of Serang Banten

    Science.gov (United States)

    Wahyuddin, Wawan

    2016-01-01

    This study wants to examine the relationship between teacher competence and emotional intelligence that held by teachers to increase the teacher performance Madrasah Tsanawiyah at district of Serang Banten. This research was conducted with the quantitative method, through analysis descriptive and inferential. Samples the research were teachers…

  4. Practicing perfection: How concert soloists prepare for performance

    Directory of Open Access Journals (Sweden)

    Roger Chaffin

    2006-01-01

    Full Text Available Musical performances by concert soloists in the Western classical tradition are normally memorized. For memory to work reliably under the pressures of the concert stage, the performance must be practiced until it is thoroughly automatic. At the same time, the performance must be fresh and spontaneous in order to communicate emotionally with the audience. The resolution of this apparent contradiction is provided by longitudinal case studies of concert soloists preparing new works for performance. Like expert memorists in other domains, experienced musicians use highly practiced retrieval schemes to accomplish their extraordinary feats of memory. Performers have a mental map of the piece in mind as they perform that tells them where they are and what comes next - a series of landmarks, hierarchically organized by the sections and subsections of the music. The musician attends to these performance cues in order to ensure that the performance unfolds as planned. Performance cues are established by thinking about a particular feature of the music during practice so that it later comes to mind automatically. Performance cues help the soloist consciously monitor and control the rapid, automatic actions of playing, while adjusting to the needs of the moment. During practice, the musician attends mostly to basic performance cues representing critical technical features (e.g., fingerings,andinterpretive performance cues, representing phrasings, and changes in dynamics, tempo, and timbre. During performance, the musician hopes to attend mainly to expressive performance cues representing the musical feelings to be conveyed to the audience (e.g. excitement. We illustrate this analysis with a typical case study of a concert pianist learning J.S. Bach's Italian Concerto (Presto.

  5. Field investigation on consumer behavior and hydraulic performance of a district heating system in Tianjin, China

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Baoping; Fu, Lin; Di, Hongfa [Department of Building Science, Tsinghua University, Beijing 100084 (China)

    2009-02-15

    With the implementation of heat reforms in China, the application of thermostatic radiator valves (TRVs) has been gaining popularity in the new-style district heating systems (DHSs). The objective of this study was to investigate consumer behavior (including regulation of TRVs and opening of windows) and its influences on the hydraulic performance and energy consumption of individuals and the whole system. The concurrence rate of individual behaviors and hydraulic interactions between individuals were analyzed. This study should be helpful to gain a comprehensive understanding of the new DHSs in China and consider a proper design/control strategy for these systems. Questionnaires and field observations of consumer behavior, tests of hydraulic performance, and surveys of energy consumption were carried out in a DHS in Tianjin, which was one of the heat metering and billing demonstration projects in China. The main results of the tests were as follows: water flow performance in apartment-level heating systems were diverse because consumers' behavior was varied and unpredictable, and the hydraulic interaction between consumers living along the line of a vertical pipe was obvious, and was stronger for terminal consumers with their TRVs set to higher values; however, flow variations in the whole DHS, which included 910 households, were relatively constant. A probability analysis was carried out to explain this phenomenon, and the conclusion was drawn that when there were more than 200 consumers, the stochastic consumer regulation behavior would bring less than 10% of total flow variations. Finally, the power consumption of the circulation pump, heat consumption and energy-saving potential of this type of DHS were discussed and some suggestions for TRV regulation and pump operation were made. (author)

  6. Improving the performance of district heating systems by utilization of local heat boosters

    DEFF Research Database (Denmark)

    Falcone, A.; Dominkovic, D. F.; Pedersen, A. S.

    LTDH grid as they will have the strategical role of connecting the heating system with the electrical energy coming from the intermittent and fluctuating renewable energy sources such as wind and solar power. In this paper a case study of district heating system is presented and analysed. The goal......District Heating (DH) plays an important role into the Danish energy green transition towards the future sustainable energy systems. The new, 4 th generation district heating network, the so called Low Temperature District Heating (LTDH), tends to lower the supply temperature of the heat down to 40......-50°C with return temperatures of 20-30 °C. This kind of heating system has many advantages and among all of them, it allows utilization of the heat coming from low exergy heat sources, as well as to decrease the grid heat losses. Electrical energy driven heat sources are also integrated into the future...

  7. Physical Preparation Recommendations for Elite Rugby Sevens Performance.

    Science.gov (United States)

    Schuster, Jake; Howells, Dan; Robineau, Julien; Couderc, Anthony; Natera, Alex; Lumley, Nick; Gabbett, Tim J; Winkelman, Nick

    2017-08-03

    Rugby Sevens, a new Olympic sport, features high intensity intermittent running and contact efforts over short match durations, normally six times across two to three days in a tournament format. Elite Rugby Sevens seasons often include over a dozen competitive tournaments across less than nine months, demanding deliberate and careful training-stress balance and workload management alongside development of the necessary physical qualities required for competition. Focus on running and repeated power skills, strength, and match-specific conditioning capacities is advised. Partial taper approaches in combination with high velocity running (>5m/s from GPS measures) exposures before and between tournaments in succession may reduce injury rates and enhance performance. In a sport with substantial long-haul intercontinental travel and repetitive chronic load demands, management of logistics including nutrition and recovery is inclusive of the formula for success in the physical preparation of elite Rugby Sevens athletes.

  8. Preparation and performance of novel thermal stable composite nanofiltration membrane

    Institute of Scientific and Technical Information of China (English)

    Chunrui WU; Shouhai ZHANG; Fajie YANG; Chun YAN; Xigao JIAN

    2008-01-01

    The novel thermal stable composite nanofiltra-tion membranes were prepared through the interfacial polymerization of piperazine and trimesoyl chloride on the poly (phthalazinone ether) ultrafiltration substrate. The effects of polymerization and testing conditions on membrane performance were studied. The surface morphologies of the substrate and the composite mem-branes were observed by means of scanning electron microscopy (SEM) and atomic force microscopy (AFM). The separation properties of membranes for dyes and salts were tested. The composite membranes show good ther-mal stability. The rejection for Na2SO4 was kept over 96%, 1.0 MPa and 80℃. When tested at 1.0 MPa and 60℃, the rejection of the composite membrane for dyes was kept at the rejection for NaCl was lower than 20%.

  9. Effect of Perovskite Film Preparation on Performance of Solar Cells

    Directory of Open Access Journals (Sweden)

    Yaxian Pei

    2016-01-01

    Full Text Available For the perovskite solar cells (PSCs, the performance of the PSCs has become the focus of the research by improving the crystallization and morphology of the perovskite absorption layer. In this thesis, based on the structure of mesoporous perovskite solar cells (MPSCs, we designed the experiments to improve the photovoltaic performance of the PSCs by improved processing technique, which mainly includes the following two aspects. Before spin-coating PbI2 solution, we control the substrate temperature to modify the crystal quality and morphology of perovskite films. On the other hand, before annealing, we keep PbI2 films for the different drying time at room temperature to optimize films morphology. In our trials, it was found that the substrate temperature is more important in determining the photovoltaic performance than drying time. These results indicate that the crystallization and morphology of perovskite films affect the absorption intensity and obviously influence the short circuit current density of MPSCs. Utilizing films prepared by mentioning two methods, MPSCs with maximum power conversion efficiency of over 4% were fabricated for the active area of 0.5 × 0.5 cm2.

  10. Do Management and Leadership Practices in the Context of Decentralisation Influence Performance of Community Health Fund? Evidence From Iramba and Iringa Districts in Tanzania

    Directory of Open Access Journals (Sweden)

    Chakupewa Joseph

    2017-05-01

    Full Text Available Background In early 1990s, Tanzania like other African countries, adopted health sector reform (HSR. The most strongly held centralisation system that informed the nature of services provision including health was, thus, disintegrated giving rise to decentralisation system. It was within the realm of HSR process, user fees were introduced in the health sector. Along with user fees, various types of health insurances, including the Community Health Fund (CHF, were introduced. While the country’s level of enrolment in the CHF is low, there are marked variations among districts. This paper highlights the role of decentralised health management and leadership practices in the uptake of the CHF in Tanzania. Methods A comparative exploratory case study of high and low performing districts was carried out. In-depth interviews were conducted with the members of the Council Health Service Board (CHSB, Council Health Management Team (CHMT, Health Facility Committees (HFCs, in-charges of health facilities, healthcare providers, and Community Development Officers (CDOs. Minutes of the meetings of the committees and district annual health plans and district annual implementation reports were also used to verify and triangulate the data. Thematic analysis was adopted to analyse the collected data. We employed both inductive and deductive (mixed coding to arrive to the themes. Results There were no differences in the level of education and experience of the district health managers in the two study districts. Almost all district health managers responsible for the management of the CHF had attended some training on management and leadership. However, there were variations in the personal initiatives of the top-district health leaders, particularly the district health managers, the council health services board and local government officials. Similarly, there were differences in the supervision mechanisms, and incentives available for the health providers

  11. Do Management and Leadership Practices in the Context of Decentralisation Influence Performance of Community Health Fund? Evidence From Iramba and Iringa Districts in Tanzania.

    Science.gov (United States)

    Joseph, Chakupewa; Maluka, Stephen Oswald

    2016-09-26

    In early 1990s, Tanzania like other African countries, adopted health sector reform (HSR). The most strongly held centralisation system that informed the nature of services provision including health was, thus, disintegrated giving rise to decentralisation system. It was within the realm of HSR process, user fees were introduced in the health sector. Along with user fees, various types of health insurances, including the Community Health Fund (CHF), were introduced. While the country's level of enrolment in the CHF is low, there are marked variations among districts. This paper highlights the role of decentralised health management and leadership practices in the uptake of the CHF in Tanzania. A comparative exploratory case study of high and low performing districts was carried out. In-depth interviews were conducted with the members of the Council Health Service Board (CHSB), Council Health Management Team (CHMT), Health Facility Committees (HFCs), in-charges of health facilities, healthcare providers, and Community Development Officers (CDOs). Minutes of the meetings of the committees and district annual health plans and district annual implementation reports were also used to verify and triangulate the data. Thematic analysis was adopted to analyse the collected data. We employed both inductive and deductive (mixed coding) to arrive to the themes. There were no differences in the level of education and experience of the district health managers in the two study districts. Almost all district health managers responsible for the management of the CHF had attended some training on management and leadership. However, there were variations in the personal initiatives of the top-district health leaders, particularly the district health managers, the council health services board and local government officials. Similarly, there were differences in the supervision mechanisms, and incentives available for the health providers, HFCs and board members in the two study

  12. A comparison of hierarchical cluster analysis and league table rankings as methods for analysis and presentation of district health system performance data in Uganda.

    Science.gov (United States)

    Tashobya, Christine K; Dubourg, Dominique; Ssengooba, Freddie; Speybroeck, Niko; Macq, Jean; Criel, Bart

    2016-03-01

    In 2003, the Uganda Ministry of Health introduced the district league table for district health system performance assessment. The league table presents district performance against a number of input, process and output indicators and a composite index to rank districts. This study explores the use of hierarchical cluster analysis for analysing and presenting district health systems performance data and compares this approach with the use of the league table in Uganda. Ministry of Health and district plans and reports, and published documents were used to provide information on the development and utilization of the Uganda district league table. Quantitative data were accessed from the Ministry of Health databases. Statistical analysis using SPSS version 20 and hierarchical cluster analysis, utilizing Wards' method was used. The hierarchical cluster analysis was conducted on the basis of seven clusters determined for each year from 2003 to 2010, ranging from a cluster of good through moderate-to-poor performers. The characteristics and membership of clusters varied from year to year and were determined by the identity and magnitude of performance of the individual variables. Criticisms of the league table include: perceived unfairness, as it did not take into consideration district peculiarities; and being oversummarized and not adequately informative. Clustering organizes the many data points into clusters of similar entities according to an agreed set of indicators and can provide the beginning point for identifying factors behind the observed performance of districts. Although league table ranking emphasize summation and external control, clustering has the potential to encourage a formative, learning approach. More research is required to shed more light on factors behind observed performance of the different clusters. Other countries especially low-income countries that share many similarities with Uganda can learn from these experiences. © The Author 2015

  13. Absent Audiences: Youth Identity Formation in Preparations for Performance

    Science.gov (United States)

    Thompson, Carol C.

    2011-01-01

    This article explores the use of audiences in preparation for public presentation by an urban youth organization in Camden, New Jersey (U.S.). Camden is an impoverished city with few opportunities for youth. The organization, a hybrid of youth development, technology, business, and college preparation, prepared youth for good jobs or college.…

  14. Assessing District Energy Systems Performance Integrated with Multiple Thermal Energy Storages

    Science.gov (United States)

    Rezaie, Behnaz

    The goal of this study is to examine various energy resources in district energy (DE) systems and then DE system performance development by means of multiple thermal energy storages (TES) application. This study sheds light on areas not yet investigated precisely in detail. Throughout the research, major components of the heat plant, energy suppliers of the DE systems, and TES characteristics are separately examined; integration of various configurations of the multiple TESs in the DE system is then analysed. In the first part of the study, various sources of energy are compared, in a consistent manner, financially and environmentally. The TES performance is then assessed from various aspects. Then, TES(s) and DE systems with several sources of energy are integrated, and are investigated as a heat process centre. The most efficient configurations of the multiple TESs integrated with the DE system are investigated. Some of the findings of this study are applied on an actual DE system. The outcomes of this study provide insight for researchers and engineers who work in this field, as well as policy makers and project managers who are decision-makers. The accomplishments of the study are original developments TESs and DE systems. As an original development the Enviro-Economic Function, to balance the economic and environmental aspects of energy resources technologies in DE systems, is developed; various configurations of multiple TESs, including series, parallel, and general grid, are developed. The developed related functions are discharge temperature and energy of the TES, and energy and exergy efficiencies of the TES. The TES charging and discharging behavior of TES instantaneously is also investigated to obtain the charging temperature, the maximum charging temperature, the charging energy flow, maximum heat flow capacity, the discharging temperature, the minimum charging temperature, the discharging energy flow, the maximum heat flow capacity, and performance

  15. A process evaluation of performance-based incentives for village health workers in Kisoro district, Uganda.

    Science.gov (United States)

    Miller, James S; Musominali, Sam; Baganizi, Michael; Paccione, Gerald A

    2014-04-08

    Designing effective incentive systems for village health workers (VHWs) represents a longstanding policy issue with substantial impact on the success and sustainability of VHW programs. Using performance-based incentives (PBI) for VHWs is an approach that has been proposed and implemented in some programs, but has not received adequate review and evaluation in the peer-reviewed literature. We conducted a process evaluation examining the use of PBI for VHWs in Kisoro, Uganda. In this system, VHWs are paid based on 20 indicators, divided among routine follow-up visits, health education activities, new patient identifications, sanitation coverage, and uptake of priority health services. Surveys of VHWs (n = 30) and program supervisors (n = 7) were conducted to assess acceptability and feasibility. Interviews were conducted with all 8 program supervisors and with 6 purposively selected VHWs to gain a deeper understanding of their views on the PBI system. Program budget records were used to assess the costs of the program. Detailed payment records were used to assess the fairness of the PBI system with respect to VHWs' gender, education level, and village location. In surveys and interviews, supervisors expressed high satisfaction with the PBI system, though some supervisors expressed concerns about possible negative effects from the variation in payments between VHWs and the uncertainty of reward for effort. VHWs perceived the system as generally fair, and preferred it to the previous payment system, but expressed a desire to be paid more. The annual program cost was $516 per VHW, with each VHW covering an average of 115 households. VHWs covering more households tended to earn more. There was some evidence that female gender was associated with higher earnings. Education level and proximity to the district hospital did not appear to be associated with earnings under the PBI system. In a one-year pilot of PBI within a small VHW program, both VHWs and supervisors found

  16. Preparation, Characterization and Performance of Conch Ceramics Added With Shell

    Directory of Open Access Journals (Sweden)

    Wang Qingyu

    2016-01-01

    Full Text Available The conch ceramics bodies with different ratios were prepared by compression moulding technology using shell, kaolin, and calcium oxide etc. as the raw materials, and then calcined at the high temperature to obtain the conch ceramics. The effects of raw material ratios and calcination temperatures on the performance of conch ceramics were investigated by rotational viscometer, vernier caliper, digital display whiteness meter, thermal analyzer, and Fourier transform infrared spectrometer(FT-IR. The results indicated that the viscosity, line shrinkage rate, and whiteness of the conch ceramics were 1.29 Pa·s, 17.9%, and 54.1%, respectively, when the content of the shell powder was 20 wt% and kaolin was 65 wt%. The density of the conch ceramics was the largest (3.8 g/cm3 when calcination temperature was 1200 °C. The results of FT-IR spectrum showed that the addition of the shell powders changed the structure of the ceramic body, which improved the performance of the conch ceramics.

  17. Teachers' Coping Strategies for Teaching Science in a ``Low-Performing'' School District

    Science.gov (United States)

    Moore, Felicia M.

    2007-10-01

    This study describes how teachers use their personal knowledge of a school district and their students to cope with teaching under stressful situations associated with economic, social, and institutional factors. The 3 teachers dealt with these issues in unique ways, focusing on helping students to overcome negative perceptions, value the importance of an education, and build strong relationships. A model of multicultural science professional development is proposed that complements the strengths that these teachers have. A task for science educators working with teachers and administration in schools and districts that are “critically low performing” is to support everyone in implementing pedagogical methods aimed at empowerment, social justice, and high achievement for all students.

  18. Excellence in Navy Recruiting: A Look at High Performing Navy Recruiting Districts

    Science.gov (United States)

    1985-12-01

    III F. RZ NAVY AND TIIE RETIRED NETWORK ............... 112 C. PROPENSITY TO ENIAST? ......................... ..... 112 XVII. W E CAN GET BETTER...the building ical. An Education Specialist added onl kiocks that form the foundation of to these thoughts that thle Competition ixcellence . We will...newspapers, and the newsletters keepthe entire staf"within the district. the communication network going, up The telephone is often the and down and

  19. Measuring health system strengthening: application of the balanced scorecard approach to rank the baseline performance of three rural districts in Zambia.

    Directory of Open Access Journals (Sweden)

    Wilbroad Mutale

    Full Text Available INTRODUCTION: There is growing interest in health system performance and recently WHO launched a report on health systems strengthening emphasising the need for close monitoring using system-wide approaches. One recent method is the balanced scorecard system. There is limited application of this method in middle- and low-income countries. This paper applies the concept of balanced scorecard to describe the baseline status of three intervention districts in Zambia. METHODOLOGY: The Better Health Outcome through Mentoring and Assessment (BHOMA project is a randomised step-wedged community intervention that aims to strengthen the health system in three districts in the Republic of Zambia. To assess the baseline status of the participating districts we used a modified balanced scorecard approach following the domains highlighted in the MOH 2011 Strategic Plan. RESULTS: Differences in performance were noted by district and residence. Finance and service delivery domains performed poorly in all study districts. The proportion of the health workers receiving training in the past 12 months was lowest in Kafue (58% and highest in Luangwa district (77%. Under service capacity, basic equipment and laboratory capacity scores showed major variation, with Kafue and Luangwa having lower scores when compared to Chongwe. The finance domain showed that Kafue and Chongwe had lower scores (44% and 47% respectively. Regression model showed that children's clinical observation scores were negatively correlated with drug availability (coeff -0.40, p = 0.02. Adult clinical observation scores were positively association with adult service satisfaction score (coeff 0.82, p = 0.04 and service readiness (coeff 0.54, p = 0.03. CONCLUSION: The study applied the balanced scorecard to describe the baseline status of 42 health facilities in three districts of Zambia. Differences in performance were noted by district and residence in most domains with finance and service

  20. Preparation and Photoelectrochemical Performance of Potassium Hexatitanate Nanofilm

    Institute of Scientific and Technical Information of China (English)

    钱清华; 刘畅; 胡煜艳; 杨祝红; 冯新; 陆小华

    2007-01-01

    Nanostructured K2Ti6O13 film photoelectrode produced in situ was prepared on indium-tin oxide (ITO) glass substrate by a sol-gel process and characterized by thermogravimetry (TG) and differential scanning calorimetry (DSC),X-ray diffraction (XRD),atomic force microscopy (AFM),UV-Visible diffuse reflectance and Raman spectrometry.The photoelectrochemical performance of K2Ti6O13 film was assessed by electrochemical method.The analytical results showed that the K2Ti6O13 film had a strong and wide absorption in the ultraviolet and visible light range.The band gap energy (Eg) of the film shifted from 3.45 eV (bulk) to 3.05 eV (film).The flat-band potential (Efb) of K2Ti6O13 film was-0.67 V [vs.saturated calomel electrode (SCE)].The transport of photogenerated electrons and holes was better in K2Ti6O13 film electrode than that in TiO2 film electrode.The photoelectrochemical response of K2Ti6O13 photoelectrode was increased in electrolyte solution with KOH,compared with that in the solution without KOH.The adsorption of OH- on the nanofilm acted as the surface activity center.The mechanism of photolysis was analyzed in terms of photoelectrochemical behavior.

  1. The Impact of Home Environment Factors on Academic Performance of Senior Secondary School Students in Garki Area District, Abuja - Nigeria

    Directory of Open Access Journals (Sweden)

    L. T. Dzever

    2015-12-01

    Full Text Available The study examined the impact of home environment factors on the academic performance of public secondary school students in Garki Area District, Abuja, Nigeria. The stratified sampling technique was used to select 300 students from six public schools, while the simple random sampling technique was used to administer the questionnaire. The study utilized a descriptive survey research design for the study. Also, data on student’s academic performance was obtained from student’s scores in four selected school subjects. Data obtained was analyzed using descriptive and inferential statistical techniques; Pearson Product Moment Correlation and Multiple regression analysis (ANOVA. The results result revealed a positive and significant relationship between permissive patenting style with academic performance (p0.05. Also, the result from the study identified income, educational background and occupational level as well as permissive parenting style as the main predictive variables influencing students’ academic performance.

  2. Self-healing epoxy composites: preparation, characterization and healing performance

    Directory of Open Access Journals (Sweden)

    Reaz A. Chowdhury

    2015-01-01

    Full Text Available Low velocity impact damage is common in fiber reinforced composites, which leads to micro-crack and interfacial debonding, where damage is microscopic and invisible. The concept of self-healing composites can be a way of overcoming this limitation and extending the life expectancy while expanding their usage in structural applications. In the current study, extrinsic self-healing concept was adopted using urea-formaldehyde microcapsules containing room temperature curing epoxy resin system (SC-15 as the healing agent prepared by in situ polymerization. Microcapsules were characterized using Fourier transform infrared spectroscopy (FTIR for structural analysis. Size and shape of microcapsules were studied using optical microscopy and scanning electron microscopy (SEM. Size of the microcapsules was between 30 and 100 μm. Thermal characterization was carried out using thermogravimetric analysis. Microcapsules were thermally stable till 210 °C without any significant decomposition. Fiber reinforced composite fabrication was carried out in three different steps. In the first step, epoxy resin was encapsulated in urea-formaldehyde shell material, which was confirmed by FTIR analysis. In the next step, encapsulation of amine hardener was achieved by vacuum infiltration method. These two different microcapsules were added with epoxy at 10:3 ratio and composite fabrication was done with hand layup method. Finally, healing performance was measured in terms of low velocity impact test and thermoscopy analysis. Low velocity impact test with 30 J and 45 J impact loads confirmed the delamination and micro-crack in composite materials and subsequent healing recovery observed in terms of damaged area reduction and restoration of mechanical properties.

  3. Special Physical Preparation of High Schoolers for Performing Parkour Exercises

    Directory of Open Access Journals (Sweden)

    Т. М. Кравчук

    2017-03-01

    Full Text Available The objective is to ground and develop a methodology of special physical preparation of high schoolers for performing parkour elements, and to experimentally verify its effectiveness. Materials and methods: Kharkiv secondary school No. 84 served as the grounds for the study. The participants in the study were boys aged 15-17: 10 persons – in the reference group, and 10 persons – in the experimental group. The methods of the study: theoretical analysis and collation of scientific and methodological literature; pedagogical observation; video recording; biomechanical analysis; talks with experts; pedagogical experiment; mathematical and statistical methods of research materials processing. Results: The experimental group showed positive improvement in the balancing technique from 3.5 points before the experiment to 6.3 after the experiment (p < 0.05; a considerable increase in points in the jumping technique, including jumps onto the wall bars hand-gripping its edge, jumps into landing with a roll, and jumps over obstacle – from 2.9, 4.2 and 4.6 points respectively at the beginning of the experiment to 5.9, 6.7 and 7.8 points respectively after the experiment (p < 0.05; positive significant improvement in the wall bars running results – from 3.2 points at the beginning of the experiment to 6.7 after the experiment (p < 0.05. Conclusions: special sets of exercises have been designed to develop and improve these abilities in parkour, and the effectiveness of the designed methodology has been experimentally verified. The study has proved that, when used in physical training of high schoolers, the special sets of exercises intended to develop parkourists’ speed, strength and coordination abilities contribute to a significant increase in the level of the technique of execution of the main parkour elements.

  4. Health worker preferences for performance-based payment schemes in a rural health district in Burkina Faso

    Directory of Open Access Journals (Sweden)

    Maurice Yé

    2016-01-01

    Full Text Available Background: One promising way to improve the motivation of healthcare providers and the quality of healthcare services is performance-based incentives (PBIs also referred as performance-based financing. Our study aims to explore healthcare providers’ preferences for an incentive scheme based on local resources, which aimed at improving the quality of maternal and child health care in the Nouna Health District. Design: A qualitative and quantitative survey was carried out in 2010 involving 94 healthcare providers within 34 health facilities. In addition, in-depth interviews involving a total of 33 key informants were conducted at health facility levels. Results: Overall, 85% of health workers were in favour of an incentive scheme based on the health district's own financial resources (95% CI: [71.91; 88.08]. Most health workers (95 and 96% expressed a preference for financial incentives (95% CI: [66.64; 85.36] and team-based incentives (95% CI: [67.78; 86.22], respectively. The suggested performance indicators were those linked to antenatal care services, prevention of mother-to-child human immunodeficiency virus transmission, neonatal care, and immunization. Conclusions: The early involvement of health workers and other stakeholders in designing an incentive scheme proved to be valuable. It ensured their effective participation in the process and overall acceptance of the scheme at the end. This study is an important contribution towards the designing of effective PBI schemes.

  5. Technique and economy to prepare biofuelled district heating plants for power production; Teknik och ekonomi foer att foerbereda nya biobraensleeldade vaermeverk foer elproduktion

    Energy Technology Data Exchange (ETDEWEB)

    Steinwall, Pontus; Nystroem, Johan; Nystroem, Olle; Svensson, Sven-Aake [Sycon Energikonsult AB, Malmoe (Sweden)

    1999-10-01

    This report deals with the technique and the economic possibilities to prepare biofuelled district heating plants for power production. In the study three types of plants are examined: (1) 10 MW Heat Boiler with uncooled grate; (2) 50 MW Heat BFB-boiler; (3) 100 MW Heat CFB-boiler. (1) 10 MW boiler with uncooled grate: For this plant we don't recommend any specific preparation to be made with regard to the boiler equipment. Instead the layout of the plant should take into account that a future conversion may involve a complete change of the hot water boiler to a steam boiler and installation of a turbine. This means that the hot water boiler should be placed near a wall and that space should be reserved for a new steam boiler with economiser. A specific preparation that can be recommended is however to invest in a flue gas fan with capacity to overcome the increased pressure loss of the economiser being an integrated part of the new boiler. (2) 50 MW BFB-boiler: If it is believed or the plan is that the plant will be converted to power production within five years, the BFB-boiler should be based on a steam boiler equipped with a superheater from start of the project. If it is likely that conversion will be done later, the plant should still be based on a steam boiler but in this case without the superheater being installed. During the time to conversion the boiler is equipped and operated such that the heat is dissipated as hot water. The reason not to produce steam from start is that a district heating plant working with steam consumes more electricity than one working with hot water. The boiler should be prepared in terms of design and space for installation of the superheater. The extra cost for the preparation is approximately six per cent of the total cost for the whole plant. (3) 100 MW CFB-boiler: The biggest plant with a heat output of 100 MW is here recommend to be prepared for power production if there are plans to do so, without bearing to the time

  6. Legislative Districts - House Districts

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This layer represents the Arkansas State House of Representatives district boundaries adopted by the Arkansas Board of Apportionment on July 29, 2011. The Board of...

  7. Legislative Districts - Senate Districts

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This layer represents the Arkansas State Senate district boundaries adopted by the Arkansas Board of Apportionment on July 29, 2011. The Board of Apportionment,...

  8. Council Districts

    Data.gov (United States)

    Town of Cary, North Carolina — View the location of the Town of Cary’s four Town Council districts.Please note that one district, District A, is split into two geo-spatial areas. One area is in...

  9. Energy performance of sprinkler irrigated maize, wheat and sunflower in Vigia irrigation district

    Energy Technology Data Exchange (ETDEWEB)

    Carvalho, Sandra; Rodrigues, Goncalo Caleia; Paredes, Paula; Pereira, Luis S. [Centro de Engenharia dos Biossistemas (CEER/ISA), Lisboa (Portugal)], E-mail: lspereira@isa.utl.pt

    2008-07-01

    The energy potential of a crop may be evaluated through life cycle assessment methodologies. These refer to the computation of the crop's energy balance and other related indicators, such as the energy ratio and the energetic efficiency, that may be used as to assess how a given irrigated crop may be used for production of biofuel. This study concerns sprinkler irrigated sunflower, wheat and maize crops using data relative to the campaign of 2007 in the Vigia Irrigation District, Alentejo. A model was developed and various scenarios were considered. The modelling results lead to the conclusion that the maize crop is the most efficient in producing energy and sunflower is the least one for all the alternative scenarios considered. (author)

  10. Examining the influence of family physician supply on district health system performance in South Africa: An ecological analysis of key health indicators.

    Science.gov (United States)

    Von Pressentin, Klaus B; Mash, Bob J; Esterhuizen, Tonya M

    2017-04-28

    The supply of appropriate health workers is a key building block in the World Health Organization's model of effective health systems. Primary care teams are stronger if they contain doctors with postgraduate training in family medicine. The contribution of such family physicians to the performance of primary care systems has not been evaluated in the African context. Family physicians with postgraduate training entered the South African district health system (DHS) from 2011. This study aimed to evaluate the impact of family physicians within the DHS of South Africa. The objectives were to evaluate the impact of an increase in family physician supply in each district (number per 10 000 population) on key health indicators. All 52 South African health districts were included as units of analysis. An ecological study evaluated the correlations between the supply of family physicians and routinely collected data on district performance for two time periods: 2010/2011 and 2014/2015. Five years after the introduction of the new generation of family physicians, this study showed no demonstrable correlation between family physician supply and improved health indicators from the macro-perspective of the district. The lack of a measurable impact at the level of the district is most likely because of the very low supply of family physicians in the public sector. Studies which evaluate impact closer to the family physician's circle of control may be better positioned to demonstrate a measurable impact in the short term.

  11. Why Rural Community Day Secondary Schools Students' Performance in Physical Science Examinations Is Poor in Lilongwe Rural West Education District in Malawi

    Science.gov (United States)

    Mlangeni, Angstone Noel J. Thembachako; Chiotha, Sosten Staphael

    2015-01-01

    A study was conducted to investigate factors that affect students' poor performance in physical science examinations at Malawi School Certificate of Education and Junior Certificate of Education levels in Community day secondary schools (CDSS) in Lilongwe Rural West Education District in Malawi. Students' performance was collected from schools'…

  12. Ready from Day One: An Examination of One Principal Preparation Program's Redesign in Collaboration with Local School Districts

    Science.gov (United States)

    Kearney, W. Sean; Valadez, Albert

    2015-01-01

    This paper presents a newly implemented model of principal preparation at a public university in the southwestern United States. The authors begin by identifying a number of innovative practices currently being carried out within educational administration programs across the United States. Informed by the context of these national models, the…

  13. The Relationship Between Mental Preparation Strategies and Motor Performance: A Review and Critique.

    Science.gov (United States)

    Weinberg, Robert S.

    1981-01-01

    This article reviews research literature on mental practice and preparation for motor performance and research on the effect of specific mental preparation strategies on skilled performance. Strategies discussed include imagery, self-efficacy statements, attentional focus, preparatory arousal, and relaxation. (Author/CJ)

  14. PERFORMANCE ANALYSIS OF METHODS FOR ESTIMATING WEIBULL PARAMETERS FOR WIND SPEED DISTRIBUTION IN THE DISTRICT OF MAROUA

    Directory of Open Access Journals (Sweden)

    D. Kidmo Kaoga

    2014-12-01

    Full Text Available In this study, five numerical Weibull distribution methods, namely, the maximum likelihood method, the modified maximum likelihood method (MLM, the energy pattern factor method (EPF, the graphical method (GM, and the empirical method (EM were explored using hourly synoptic data collected from 1985 to 2013 in the district of Maroua in Cameroon. The performance analysis revealed that the MLM was the most accurate model followed by the EPF and the GM. Furthermore, the comparison between the wind speed standard deviation predicted by the proposed models and the measured data showed that the MLM has a smaller relative error of -3.33% on average compared to -11.67% on average for the EPF and -8.86% on average for the GM. As a result, the MLM was precisely recommended to estimate the scale and shape parameters for an accurate and efficient wind energy potential evaluation.

  15. Enhanced Performance of Community Health Service Centers during Medical Reforms in Pudong New District of Shanghai, China: A Longitudinal Survey.

    Directory of Open Access Journals (Sweden)

    Xiaoming Sun

    Full Text Available The performance of community health service centers (CHSCs has not been well monitored and analysed since China's latest community health reforms in 2009. The aim of the current investigation was to evaluate the performing trends of the CHSCs and to analyze the main factors that could affect the performance in Pudong new district of Shanghai, China.A regional performance assessment indicator system was applied to the evaluation of Pudong CHSCs' performance from 2011 to 2013. All of the data were sorted out by a panel, and analyzed using descriptive statistics and a generalized estimating equation model.We found that the overall performance increased annually, with a growing number of CHSCs achieving high scores. Significant differences were observed in institutional management, public health services, basic medical services and comprehensive satisfaction during the period of three years. However, we found no differences in the service scores of Chinese traditional medicine (CTM. The investigation also demonstrated that the key factors affecting performance were the location, information system level, family GP program and medical association program rather than the size of the center. However, the medical association participation appeared to have a significant negative effect on performance.It can be concluded from the three-year investigation that the overall performance was improved, but that it could have been further enhanced, especially in institutional management and basic medical service; therefore, it is imperative that CHSCs undertake approaches such as optimizing the resource allocation and utilization, reinforcing the establishment of the information system level, extending the family GP program to more local communities, and promoting the medical association initiative.

  16. Preparation of activated ceria and its desulfurization performance

    Institute of Scientific and Technical Information of China (English)

    Qing-chun Yu; Yong Deng; Fei Wang; Yue-bin Feng; Xiu-min Chen; Bin Yang; Da-chun Liu

    2015-01-01

    Activated ceria (CeO2/γ-Al2O3) prepared by impregnation was characterized by X-ray diffraction (XRD), scanning electron mi-croscopy (SEM), and hydrogen temperature-programmed reduction (TPR). The desulfurization of the activated ceria was investigated by X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FT-IR), and thermogravimetric analysis (TG). The results showed that ceria could be highly dispersed or crystallized on the surface ofγ-alumina. The reduction temperatures of 0.1CeO2/γ-Al2O3, 0.45CeO2/γ-Al2O3, and CeO2 ranged from 250°C to 470°C, 330°C to 550°C, and 350°C to 550°C, respectively. The reduction peak tem-perature of 0.45CeO2/γ-Al2O3 was higher than that of 0.1CeO2/γ-Al2O3, which was consistent with the reduction temperature of CeO2. O2 participated in the reaction between ceria and sulfur dioxide. The desulfurization product was cerium(III) sulfate. The intensity of the hy-droxyl band decreased with the formation of sulfate species.

  17. Electrochemical preparation and performance of γ-MnO2

    Institute of Scientific and Technical Information of China (English)

    ZHANG Zhao-di; XU Long-jun; SHI Jian-hang; XU Wei; WU Wen-li; LIU Cheng-lun

    2015-01-01

    The effects of the electro-deposition conditions on the crystal structure and the properties of electrolytic manganese dioxide (EMD) were investigated in this paper. The results show that EMD was γ-crystal, with sand-like rough interface. The optimal preparation conditions of EMD were 30 min deposition time, and pH=1.0 in MnSO4-H2SO4 solution at 50 °C. Surfactant (P1) was conducive to the uniform and stable surface of γ-MnO2 film, the impedance and the specific surface area of the electrode modified with γ-MnO2 increased by 21.4 times and 75.6 times, respectively. The redox reversibility and the resolution ratio of characteristic peaks with the modified electrode were significantly improved in the benzodiazepines electrochemical reaction. The achievement illustrated that the controllable synthesis of γ-MnO2 film thickness was practical in electrochemical sensors, and the determination reliability of benzodiazepines was improved with γ-MnO2 modified electrodes used in environment monitoring technology.

  18. Range-dependent sonar performance modelling during Battlespace Preparation 2007

    NARCIS (Netherlands)

    Raa, L.A. te; Lam, F.P.A.; Schouten M.W.; Janmaat, J.

    2009-01-01

    Spatial and temporal variations in sound speed can have substantial effects on sound propagation and hence sonar performance. Operational oceanographic models can provide forecasts of oceanographic variables as temperature, salinity and sound speed up to several days ahead. These four-dimensional fo

  19. THE ROLE OF PREPARATION IN OVERLAPPING-TASK PERFORMANCE

    NARCIS (Netherlands)

    de Jong, Robert (Rob)

    1995-01-01

    We examined how performance of two overlapping discrete tasks is organized and controlled. Experiment 1 showed that when stimuli were presented in an unexpected order, expectations rather than actual presentation order determined the order in which the two stimuli were processed. In Experiment 2, wh

  20. Improvement in SOFC anode performance by finely-structured Ni/YSZ cermet prepared via heterocoagulation.

    Science.gov (United States)

    Sunagawa, Yoji; Yamamoto, Katsutoshi; Muramatsu, Atsushi

    2006-03-30

    A novel preparation technique for a nanostructured anode for a solid oxide fuel cell is investigated. By mixing nanometer-sized NiO and YSZ powders in a pH-controlled aqueous media, a fine mixture of nanoparticles is successfully obtained through heterocoagulation. The anode prepared from thus prepared mixture has a large triple phase boundary and shows a great improvement in the anode performance by increasing the electric conductivity and effective surface area.

  1. Preparation and Performance Study of a New Type Lead Paste

    Institute of Scientific and Technical Information of China (English)

    GAO Jun; SHI Peng-fei; YANG Tao

    2006-01-01

    A new type lead paste mixed with binders used in thin-plate, spirally wound lead acid batteries is introduced. The utility of positive active material can obtain 54.17% and 37.71% at discharge currents of 0.5C and 5.0C. The investigation was performed by means of X-ray diffraction (XRD), scaning electron microscopy (SEM), infrared spectroscopy (IR), cylic voltammetry (CV), the results revealed more details on the reaction mechanism of paste-mixing. Further conclusion can be obtained that the reaction of paste-mixing is a physical process, and the chemical reactions is local reaction, which is different from traditional mixing process, the binders has some effect on the formation of battery process. The binders can dissolve in electrolyte, which have no disadvantageous effect on the charge-discharge performance.

  2. Modeling Student Performance in Mathematics Using Binary Logistic Regression at Selected Secondary Schools a Case Study of Mtwara Municipality and Ilemela District

    Science.gov (United States)

    Mabula, Salyungu

    2015-01-01

    This study investigated the performance of secondary school students in Mathematics at the Selected Secondary Schools in Mtwara Municipality and Ilemela District by Absenteeism, Conduct, Type of School and Gender as explanatory Factors. The data used in the study was collected from documented records of 250 form three students with 1:1 gender…

  3. How Eight State Education Agencies in the Northeast and Islands Region Identify and Support Low-Performing Schools and Districts. Summary. Issues & Answers. REL 2009-No. 068

    Science.gov (United States)

    Hergert, Leslie F.; Gleason, Sonia Caus; Urbano, Carole

    2009-01-01

    This document presents a summary of the report, "How Eight State Education Agencies in the Northeast and Islands Region Identify and Support Low-Performing Schools and Districts." This larger report describes and analyzes how eight state education agencies in the Northeast and Islands Region (Connecticut, Maine, Massachusetts, New…

  4. How Eight State Education Agencies in the Northeast and Islands Region Identify and Support Low-Performing Schools and Districts. Issues & Answers. REL 2009-No. 068

    Science.gov (United States)

    Hergert, Leslie F.; Gleason, Sonia Caus; Urbano, Carole

    2009-01-01

    This report describes and analyzes how eight state education agencies in the Northeast and Islands Region (Connecticut, Maine, Massachusetts, New Hampshire, New York, Puerto Rico, Rhode Island, and Vermont) identify and support low-performing schools and districts under the No Child Left Behind Act of 2001 (NCLB). Data collection for the report…

  5. The Effect of Leadership Styles on Learners' Performance. The Case of Asonomaso Nkwanta in the Kwabre District Assembly of Ashanti Region in Ghana

    Science.gov (United States)

    Gyasi, Richard Sarfo; Xi, Wang Bao; Owusu-Ampomah, Yvonne

    2016-01-01

    The purpose of this study was to explore the effect of leadership styles on academic performance in Junior High Schools (JHS) in Asonomaso Nkwanta in the Kwabre District Assembly of Ashanti Region in Ghana. The design for the study was a mixed study using both the qualitative and quantitative analyzes. It was a correlation survey designed to…

  6. Relationship of Nutrition and Physical Activity Behaviors and Fitness Measures to Academic Performance for Sixth Graders in a Midwest City School District

    Science.gov (United States)

    Edwards, Jane U.; Mauch, Lois; Winkelman, Mark R.

    2011-01-01

    Background: To support curriculum and policy, a midwest city school district assessed the association of selected categories of nutrition and physical activity (NUTR/PA) behaviors, fitness measures, and body mass index (BMI) with academic performance (AP) for 800 sixth graders. Methods: Students completed an adapted Youth Risk Behavior…

  7. Relationship between the TCAP and the Pearson Benchmark Assessment in Elementary Students' Reading and Math Performance in a Northeastern Tennessee School District

    Science.gov (United States)

    Dugger-Roberts, Cherith A.

    2014-01-01

    The purpose of this quantitative study was to determine if there was a relationship between the TCAP test and Pearson Benchmark assessment in elementary students' reading and language arts and math performance in a northeastern Tennessee school district. This study involved 3rd, 4th, 5th, and 6th grade students. The study focused on the following…

  8. Distributed ecohydrological modelling to evaluate the performance of irrigation system in Sirsa district, India: I. Current water management and its productivity

    NARCIS (Netherlands)

    Singh, R.; Kroes, J.G.; Dam, van J.C.; Feddes, R.A.

    2006-01-01

    Distributed ecohydrological modelling can provide a useful toot to evaluate the performance of irrigation systems at different spatial and temporal scales. Sirsa district, covering 4270 km(2) in the western part of Haryana State (India), has been selected for a case study with typical problems of

  9. An Empirical Determination of Tasks Essential to Successful Performance as a Soil Conservation District Aide. Determination of a Common Core of Basic Skills in Agribusiness and Natural Resources.

    Science.gov (United States)

    Waddy, Paul H.; And Others

    To improve vocational educational programs in agriculture, occupational information on a common core of basic skills within the occupational area of the soil conservation district aide is presented in the revised task inventory survey. The purpose of the occupational survey was to identify a common core of basic skills which are performed and are…

  10. Relationship of Nutrition and Physical Activity Behaviors and Fitness Measures to Academic Performance for Sixth Graders in a Midwest City School District

    Science.gov (United States)

    Edwards, Jane U.; Mauch, Lois; Winkelman, Mark R.

    2011-01-01

    Background: To support curriculum and policy, a midwest city school district assessed the association of selected categories of nutrition and physical activity (NUTR/PA) behaviors, fitness measures, and body mass index (BMI) with academic performance (AP) for 800 sixth graders. Methods: Students completed an adapted Youth Risk Behavior…

  11. Intervention Program for Long-Term English Learners: A Study of Long-Term English Learners' Literacy Performance in a Reading Intervention Program at Falcon School District

    Science.gov (United States)

    Ayala, Erika

    2016-01-01

    The purpose of this sequential explanatory embedded mixed methods study was to: (a) investigate and describe the academic performance of eighth grade students in the Falcon School District (FSD) who were designated as Long Term English Learners (LTELs) and participants in FSD's reading intervention program during their fourth through eighth grade…

  12. Arsenic Removal from Drinking Water by Adsorptive Media U.S. EPA Demonstration Project at Webb Consolidated Independent School District in Bruni, TX - Final Performance Evaluation Report

    Science.gov (United States)

    This report documents the activities performed and the results obtained from the arsenic removal treatment technology demonstration project at the Webb Consolidated Independent School District (Webb CISD) in Bruni, TX. The main objective of the project was to evaluate the effect...

  13. Performance Appraisals of School Administrators in One Canadian School District: A Contemporary Model

    Science.gov (United States)

    Normore, Anthony H.

    2004-01-01

    Research indicates that a sound performance appraisal process for school administrators contains key mechanisms that manifest themselves through dimensions of effective planning, assessment, and evaluation; effective use of resources; and communicating clear expectations. This article documents the development of a contemporary model of…

  14. FACTORS INFLUENCING PERFORMANCE IN BASIC TECHNOLOGY AMONG SECONDARY SCHOOL STUDENTS Of DELTA SOUTH SENATORIAL DISTRICT IN DELTA STATE, NIGERIA

    Directory of Open Access Journals (Sweden)

    Serumu Igberadja

    2015-12-01

    Full Text Available Similar to other science subjects, basic technology recorded poor secondary school students’ performance both in national and international examination. Furthermore, there are large variations in performances of Nigerian students that raise concerns. These differences in performance may be caused by multiple factors that need to be identified. The aim of this study is to identify the factors that influence students’ performance in basic technology. Four research questions guided the study and four hypotheses were tested at the .05 level of significance. The study used the survey research design method with 218 principals of secondary schools in Delta South Senatorial District in Delta State of Nigeria as the target population. The stratified random sampling technique was used to select 65 principals (32 from public and 33 from private secondary schools as sample of the study. The instrument for data collection was a questionnaire which was content and face validated by three lecturers. The test-retest method was used to ascertain the reliability based on 20 principals who were not part of the population under study. The estimated reliability r= 0.73. Data was collected personally by the researcher and was analysed using ANOVA (Analysis of variance. The result revealed that multiple factors; schools’, students’, government, and parents’ factors influenced students’ performance in basic technology with lack of resources underlying these factors.  Hence, it was recommended among others that Delta State Ministry of Basic Education should adequately provide the required resources for the teaching and learning of basic technology in secondary schools in Delta State.

  15. Numerical evaluation of plate heat exchanger performance in geothermal district heating systems

    Energy Technology Data Exchange (ETDEWEB)

    Karlsson, T. [Iceland Univ., Reykjavik (Iceland)

    1996-12-31

    This paper describes the performance of plate heat exchangers in residential water radiator heating systems receiving their heat from geothermal resources. Radiator theory is reviewed and determination of annual hot water requirements for space heating is discussed. Performance evaluation is made of plate heat exchangers and results obtained by means of two equations commonly used for this purpose, the Sieder-Tate and the Dittus-Boelter equations, compared to results obtained with a simplified equation where heat transfer in the heat exchanger is assumed to depend only on the fluid mass flow on both sides. It is found that for prevailing temperature ranges in Icelandic geothermal systems the mass pow approximation gives results very close to those determined by the more complicated conventional equations. (UK)

  16. Examining the influence of family physician supply on district health system performance in South Africa: An ecological analysis of key health indicators

    Directory of Open Access Journals (Sweden)

    Klaus B. von Pressentin

    2017-01-01

    Full Text Available Background: The supply of appropriate health workers is a key building block in the World Health Organization’s model of effective health systems. Primary care teams are stronger if they contain doctors with postgraduate training in family medicine. The contribution of such family physicians to the performance of primary care systems has not been evaluated in the African context. Family physicians with postgraduate training entered the South African district health system (DHS from 2011.Aim: This study aimed to evaluate the impact of family physicians within the DHS of South Africa. The objectives were to evaluate the impact of an increase in family physician supply in each district (number per 10 000 population on key health indicators.Setting: All 52 South African health districts were included as units of analysis.Methods: An ecological study evaluated the correlations between the supply of family physicians and routinely collected data on district performance for two time periods: 2010/2011 and 2014/2015.Results: Five years after the introduction of the new generation of family physicians, this study showed no demonstrable correlation between family physician supply and improved health indicators from the macro-perspective of the district.Conclusion: The lack of a measurable impact at the level of the district is most likely because of the very low supply of family physicians in the public sector. Studies which evaluate impact closer to the family physician’s circle of control may be better positioned to demonstrate a measurable impact in the short term.

  17. Analysis of performance indicators in municipal districts in southern Brazil with more than 100 thousand people

    Directory of Open Access Journals (Sweden)

    Delci Grapégia Dal Vesco

    2014-09-01

    Full Text Available The theme for this study is focused on public choices theory, in order to detect differences in indicators of economic and financial performance, proposed by Brown (1993 in cities of southernBrazilwith more than 100.000 inhabitants. The theoretical framework includes the public choice theory first proposed by Buchanan and indicators of financial performance classified into: (1 revenue (2 expense, (3 operational structure and (4 debt structure. The theme is justified for the domain of scientific knowledge, with a view to choosing indicators and also the size of cities. We conducted an empirical study, with sectional view in the cities of southernBrazil. The methodology is characterized as descriptive, document and quantitative. The technique used was cluster analysis and linear regression. Among the results, it is emphasized that the analysis of Cluster results are consistent with the theory proposed by Brown (1993 indicating that there are limitations in interpreting the analyzes the financial condition of cities if not by comparisons with comparable cities. The distinction between sizes of cities brought reflections on the analysis of indicators. Future research should include other municipalities in other regions. It is also suggested to continue this research and develop a comparison between the Brazilian regions relating the results of Cluster (eigenvalues with cities above 100,000 inhabitants by means of regression.

  18. Preparation

    Directory of Open Access Journals (Sweden)

    M.M. Dardir

    2014-03-01

    Full Text Available Some hexanamide-mono and di-linoleniate esters were prepared by the reaction of linolenic acid and hexanamide (derived from the reaction of hexanoic acid and diethanolamine. The chemical structure for the newly prepared hexanamide-mono and di-linoleniate esters were elucidated using elemental analysis, (FTIR, H 1NMR and chemical ionization mass spectra (CI/Ms spectroscopic techniques. The results of the spectroscopic analysis indicated that they were prepared through the right method and they have high purity. The new prepared esters have high biodegradability and lower toxicity (environmentally friendly so they were evaluated as a synthetic-based mud (ester-based mud for oil-well drilling fluids. The evaluation included study of the rheological properties, filtration and thermal properties of the ester based-muds formulated with the newly prepared esters compared to the reference commercial synthetic-based mud.

  19. Study on Model for Assessmentof Quality Management Performance of Coal Preparation Plant in CIMS

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    In this paper the method to calculate intangible quality cost is put forward for the first time based on theproduction and management characteristics of coal preparation plant. A model for assessment of quality manage-ment performance of coal preparation plant is established on the ground of quality cost. By using of CIMS integra-tion environment the strategy to carry out the model and the application example are also offered. It provides a newand feasible way to assess performance quality management of coal preparation plant.

  20. SOCIAL PRACTICE PERFORMED BY BALINESE SCULPTORS IN DISTRICTS OF UBUD AND SUKAWATI TO PRY INTO THE LAW OF PHORNOGRAPHY

    Directory of Open Access Journals (Sweden)

    I Ketut Sudita

    2013-02-01

    Full Text Available Balinese sculptors in districts of Ubud and Sukawati, Gianyar, Bali pry into the Law of Pornography. Those who agree state that the law is needed to maintain the morality which has been getting worse, and those who disagree state that it may emasculate their freedom and creativities. This study gives answers to (1 what social practices were performed by the Balinese sculptors to pry into the Law of Pornography?, (2 why did they pry into the application of the law?, and (3 what was the meaning of their prying? Several relevant critical theories such as the theory of structuration, the theory of hegemony, and the theory of aesthetics were eclectically used in this study. The data needed were collected through observation, in-depth interview, documentation study, and library research. The result of the study showed that the Balinese sculptors showed their resistance to the application of the law by making adaptation, changing profession, and still producing pornographic works. The sanction which might be imposed upon them, the consumers of pornographic works decreased, and they were eliminated from exhibitions scared them when they pried into the law. What they did could not be separated from economic, political, ideological, moral, and ethic factors. The meaning of their prying was that it caused them to lose their idealism, their consumers went down, and the number of pornographic works dropped as well.

  1. Barriers to Encourage Motivation in Relation to Work Performance of Nurses in Buleleng District Hospital

    Directory of Open Access Journals (Sweden)

    Budiastri .

    2014-08-01

    Full Text Available Background and purpose: Nurses at hospitals regularly receives criticism from the general public, negativelycommenting on their lack of patient care, lack of professionalism and diminished quality of service. Survey findings onpatient satisifaction at Buleleng Public Hospital from 2011 indicate that 2.03% of patients remained unsatisfied withstaff workplace attitudes and 6.39% felt that nursing service overall was unsatisifactory. Preliminary interviews withward nurses on 24 November 2012 exposed a number of issues: a lack of career support and development for nurses,including opportunities to expand their skills, and a lack of workplace satisifaction from patient supplementary income.Weakness regarding technical support and motivation from ward supervisors evidently also has an impact on nursesworkplace motivation and therefore quality of service. This research investigates the influence of supervision, careerdevelopment, supplementary income support, and administrational records on the workplace attitude of nursing staff.Methods: Research was formulated using qualitative and phenomenology methods. Informants were purposivelyselected. Data was collected through in-depth interviews and administration documentation study and analysed usingthematic analysis.Results and conclusion: Findings indicated that little monitoring and evaluation of nurse workplace attitudes, alack of support and motivational direction from supervisors, administrational documentation issues, minimunsupplementary income support, as well as career development had a large impact on nurse quality of care. Mostdominant variables included supervision, career development and supplementary income support.Keywords: motivation, nurse’s performance, nursing care

  2. The influence of training and mental skills preparation on injury incidence and performance in marathon runners.

    Science.gov (United States)

    Hamstra-Wright, Karrie L; Coumbe-Lilley, John E; Kim, Hajwa; McFarland, Jose A; Huxel Bliven, Kellie C

    2013-10-01

    There has been a considerable increase in the number of participants running marathons over the past several years. The 26.2-mile race requires physical and mental stamina to successfully complete it. However, studies have not investigated how running and mental skills preparation influence injury and performance. The purpose of our study was to describe the training and mental skills preparation of a typical group of runners as they began a marathon training program, assess the influence of training and mental skills preparation on injury incidence, and examine how training and mental skills preparation influence marathon performance. Healthy adults (N = 1,957) participating in an 18-week training program for a fall 2011 marathon were recruited for the study. One hundred twenty-five runners enrolled and received 4 surveys: pretraining, 6 weeks, 12 weeks, posttraining. The pretraining survey asked training and mental skills preparation questions. The 6- and 12-week surveys asked about injury incidence. The posttraining survey asked about injury incidence and marathon performance. Tempo runs during training preparation had a significant positive relationship to injury incidence in the 6-week survey (ρ[93] = 0.26, p = 0.01). The runners who reported incorporating tempo and interval runs, running more miles per week, and running more days per week in their training preparation ran significantly faster than did those reporting less tempo and interval runs, miles per week, and days per week (p ≤ 0.05). Mental skills preparation did not influence injury incidence or marathon performance. To prevent injury, and maximize performance, while marathon training, it is important that coaches and runners ensure that a solid foundation of running fitness and experience exists, followed by gradually building volume, and then strategically incorporating runs of various speeds and distances.

  3. Preparation and performance of photocatalytic regenerationable activated carbon prepared via sol-gel TiO2

    Institute of Scientific and Technical Information of China (English)

    LIU Shou-xin; SUN Cheng-lin

    2006-01-01

    Preparation ofphotocatalytic regenerationable activated carbon (AC) is the key step for the practical application of in situ regeneration of exhausted AC. A novel photocatalytic regenerationable AC was prepared by sol-gel TiO2 in this work. The adsorption and regeneration performance of TiO2/AC were evaluated using phenol as model compound. Scanning electron microscope (SEM)and nitrogen (77 K) adsorption isotherm were used to determine the surface area, pore structure and the distribution of TiO2. The results showed that with the increase of TiO2 loading, adsorption capacity of TiO2/AC decreased and the regeneration efficiency increased. The photocatalytic regenerationable AC with suitable TiO2 loading (2 wt%) exhibited suitable adsorption capacity and regeneration efficiency. TiO2 located mainly in the entrance of macro-pore of carbon. The prepared TiO2/AC exhibited similar surface structure and pore structure with material carbon.

  4. Industrial preparation and performance testing of property-modified prebaked carbon anodes for aluminum electrolysis

    Institute of Scientific and Technical Information of China (English)

    肖劲; 李劼; 邹忠; 胡国荣; 赖延清; 刘业翔

    2003-01-01

    On the base of filtering composite additives in laboratory, the industrial property-modified prebaked car-bon anodes containing composite additives were prepared in factory. The performance tests show that this kind ofanodes not only have the same excellent physical performance as common (contrasting) ones used in aluminum elec-trolysis production at the present time, but also have better chemical and electrochemical performance than that ofthe common ones. Furthermore, the industrial preparation of the property-modified prebaked anode lays the founda-tion of electrolysis test. It can be forecasted that property-modified anodes will have good behavior in aluminum elec-trolysis production.

  5. Sleep Patterns and Academic Performance during Preparation for College Entrance Exam in Chinese Adolescents

    Science.gov (United States)

    Wang, Guanghai; Ren, Fen; Liu, Zhijun; Xu, Guangxing; Jiang, Fan; Skora, Elizabeth; Lewin, Daniel S.

    2016-01-01

    Background: Deficient sleep is linked to detrimental outcomes in health and school performance for adolescents. This study characterized sleep patterns in Chinese adolescents preparing for the College Entrance Exam (CEE) and evaluated the association between sleep patterns, self-rated academic performance, and the CEE scores. Methods: A sample of…

  6. Do liquid-based preparations of urinary cytology perform differently than classically prepared cases? Observations from the College of American Pathologists Interlaboratory Comparison Program in Nongynecologic Cytology.

    Science.gov (United States)

    Laucirica, Rodolfo; Bentz, Joel S; Souers, Rhona J; Wasserman, Patricia G; Crothers, Barbara A; Clayton, Amy C; Henry, Michael R; Chmara, Beth Anne; Clary, Karen M; Fraig, Mostafa M; Moriarty, Ann T

    2010-01-01

    The cytomorphology of liquid-based preparations in urine cytology is different than classic slide preparations. To compare the performance of liquid-based preparation specimens to classically prepared urine specimens with a malignant diagnosis in the College of American Pathologists Interlaboratory Comparison Program in Nongynecologic Cytology. Participant responses between 2000 and 2007 for urine specimens with a reference diagnosis of high-grade urothelial carcinoma/carcinoma in situ/dysplasia (HGUCA), squamous cell carcinoma, or adenocarcinoma were evaluated. ThinPrep and SurePath challenges were compared with classic preparations (smears, cytospins) for discordant responses. There were 18 288 pathologist, 11 957 cytotechnologist, and 8086 "laboratory" responses available. Classic preparations comprised 90% (n = 34 551) of urine challenges; 9% (n = 3295) were ThinPrep and 1% (n = 485) were SurePath. Concordance to the general category of "positive-malignant" was seen in 92% of classic preparations, 96.5% of ThinPrep, and 94.6% of SurePath challenges (P Liquid-based preparations performed significantly better in urinary cytology challenges when evaluating malignant categories in the College of American Pathologists interlaboratory comparison program. The liquid-based preparation challenges also performed better for the exact reference interpretation of HGUCA, but no difference was observed for adenocarcinoma challenges. Cytotechnologists perform better than pathologists for all slide types, as well as those demonstrating HGUCA. These results suggest that liquid-based preparations facilitate a more accurate diagnosis than conventional preparations.

  7. A validated high performance thin layer chromatography method for determination of yohimbine hydrochloride in pharmaceutical preparations

    OpenAIRE

    Badr, Jihan M.

    2013-01-01

    Background: Yohimbine is an indole alkaloid used as a promising therapy for erectile dysfunction. A number of methods were reported for the analysis of yohimbine in the bark or in pharmaceutical preparations. Materials and Method: In the present work, a simple and sensitive high performance thin layer chromatographic method is developed for determination of yohimbine (occurring as yohimbine hydrochloride) in pharmaceutical preparations and validated according to International Conference of Ha...

  8. Local Stakeholders’ Perceptions about the Introduction of Performance-Based Financing in Benin: A Case Study in Two Health Districts

    Directory of Open Access Journals (Sweden)

    Elisabeth Paul

    2014-09-01

    Full Text Available Background Performance-Based Financing (PBF has been advanced as a solution to contribute to improving the performance of health systems in developing countries. This is the case in Benin. This study aims to analyse how two PBF approaches, piloted in Benin, behave during implementation and what effects they produce, through investigating how local stakeholders perceive the introduction of PBF, how they adapt the different approaches during implementation, and the behavioural interactions induced by PBF. Methods The research rests on a socio-anthropological approach and qualitative methods. The design is a case study in two health districts selected on purpose. The selection of health facilities was also done on purpose, until we reached saturation of information. Information was collected through observation and semi-directive interviews supported by an interview guide. Data was analysed through contents and discourse analysis. Results The Ministry of Health (MoH strongly supports PBF, but it is not well integrated with other ongoing reforms and processes. Field actors welcome PBF but still do not have a sense of ownership about it. The two PBF approaches differ notably as for the organs in charge of verification. Performance premiums are granted according to a limited number of quantitative indicators plus an extensive qualitative checklist. PBF matrices and verification missions come in addition to routine monitoring. Local stakeholders accommodate theoretical approaches. Globally, staff is satisfied with PBF and welcomes additional supervision and training. Health providers reckon that PBF forces them to depart from routine, to be more professional and to respect national norms. A major issue is the perceived unfairness in premium distribution. Even if health staff often refer to financial premiums, actually the latter are probably too weak—and ‘blurred’—to have a lasting inciting effect. It rather seems that PBF motivates health

  9. Isolation and purification of heroin from heroin street samples by preparative high performance liquid chromatography.

    Science.gov (United States)

    Guo, Zhen; Zheng, Hui; Lu, Yanzhen; Wei, Yun

    2012-09-10

    The present study established a novel method using preparative high performance liquid chromatography to isolate and purify heroin·HCl from heroin street samples to be used as a reference standard. Different kinds of mobile phases and columns were used, ultimately the mobile phase consisting of hexane-isopropanol-methanol (65:28:7, v/v) and the SIL preparative column prepared in laboratory were selected as the final condition. Heroin was further purified by the drowning-out crystallization method using isopropanol-methanol (50:1, v/v) and hexane as drowning-out anti-solvents and salting-out agents, respectively. The purity was assessed by analytical high performance liquid chromatography and the confirmation of the chemical structure was performed by IR and NMR. About 110.7mg of heroin·HCl at a purity of over 99.52% was obtained from 180mg of heroin street samples which contained 156.15mg of heroin·HCl component by preparative high performance liquid chromatography. This method is suitable for preparing heroin standards in forensic science area.

  10. Compared to Performance of Ni / SiO2 Optical Attenuator by Two Preparing Methods

    Directory of Open Access Journals (Sweden)

    Dong Pengzhan

    2016-01-01

    Full Text Available In this paper, the preparation of Ni / SiO2 optical attenuator using two kinds of process, were discussed for electroless plating and magnetron sputtering technology, by analyzing Ni film appearance , surface morphology, film composition, SiO2 substrate and Ni film adhesion, known magnetron sputtering Ni film in all aspects of performance are better than electroless plating Ni film. Electroless plating Ni film quality not up to such requirements, can not be used in the practice. Conclusions: performance of Ni / SiO2 Optical Attenuator more practical and reliable by magnetron sputtering process preparing.

  11. Resurrecting Pragmatism as a Philosophical Frame for Understanding, Researching, and Developing Performance in the Small District Superintendency

    Science.gov (United States)

    Ivory, Gary; McClellan, Rhonda; Hyle, Adrienne E.

    2009-01-01

    In this article, the authors propose that pragmatism is a perspective with great promise for understanding and researching the work of small district superintendents and developing the abilities of both pre-service students and in-service practitioners to do that work. They maintain, based on their reading of focus group interviews with small…

  12. The Correlates of Academic Performance for English Language Learner Students in a New England District. REL 2014-020

    Science.gov (United States)

    Parker, Caroline E.; O'Dwyer, Laura M.; Irwin, Clare W.

    2014-01-01

    This study examined student and program characteristics that are related to English proficiency and content area achievement for English language learner (ELL) students in one urban district in Connecticut. The study found that ELL students in special education had English proficiency scores significantly lower than the mean for all ELL students…

  13. How School Districts Can Support Deeper Learning: The Need for Performance Alignment. Executive Summary. Deeper Learning Research Series

    Science.gov (United States)

    Honig, Meredith I.; Rainey, Lydia R.

    2015-01-01

    School district leaders nationwide aspire to help their schools become vibrant places for learning--where students have meaningful academic opportunities "and" develop critical thinking and problem-solving skills, the ability to communicate effectively, and other deeper learning capacities that are essential to success in later life.…

  14. The differences of electrochemical performance between the purchased lead carbonate and the prepared lead carbonate

    Institute of Scientific and Technical Information of China (English)

    包有富

    2005-01-01

    The differences of electrochemistry performance between the purchased lead carbonate and the prepared lead carbonate were studied by the methods of cycle voltammogram, electrochemical impedance spectroscope (EIS), constant current discharge, thermal gravimetric analysis, and scan electron microscope (SEM) etc. in the paper. It was showed that the reacting activity of the prepared lead carbonate was higher than that of the purchased lead carbonate. And several points of view were concluded as follows. (1) The prepared lead carbonate contains chemical structure water, but the purchased lead carbonate doesn't contain chemical structure water. (2) The main chemical substance in the purchased lead carbonate powder is PbCO3, while the one in the prepared lead carbonate is smaller than that of the pur-chased lead carbonate.

  15. Preparation of Highly Purified Stearidonic Acid from Echium Oil via an Enzymatic Method Combined with Preparative High Performance Liquid Chromatography.

    Science.gov (United States)

    Baik, Ji Yeon; Kim, Nam Ho; Oh, Se-Wook; Kim, In-Hwan

    2015-01-01

    Stearidonic acid (SDA), an n-3 polyunsaturated fatty acid (PUFA), can be obtained from plant origin oils and it can be a good source of PUFA for vegetarians. SDA can be easily converted to longer PUFA such as docosahexaenoic acid and eicosapentaenoic acid. Highly purified stearidonic acid (SDA) was prepared successfully from echium oil via an enzymatic method combined with preparative high performance liquid chromatography. In the 1(st) step, SDA enrichment was accomplished using Candida rugosa lipase and 39.5% of SDA was obtained in the fatty acid fraction. Subsequently, the 1(st) reaction mixture was used for the 2(nd) enzymatic esterification without any separation process. The 2(nd) esterification was conducted for further SDA enrichment in a packed-bed reactor using Lipozyme RM IM from Rhizomucor miehei and the SDA content increased in a very short residence time. Ethanol was selected as an appropriate alcohol to react as an acyl receptor, and the other conditions for SDA enrichment were optimized at 20°C of temperature, and 1:4 of molar ratio (i.e., fatty acid to ethanol). Under these conditions, 51.6% of SDA was obtained in the fatty acid fraction after a residence time of 15 min. Finally, highly purified SDA (purity, >99%) was obtained by prep-HPLC using the SDA-rich fraction obtained from the two-step lipase-catalyzed esterification.

  16. Preparation and Performance Evaluation of Biochars from Neem Seed Active Substance Extracted Residues (NSASER)

    Science.gov (United States)

    Li, Jialei; Lu, Shuwen

    2017-05-01

    Neem seed active substance extracted residues (NSASER) is industrial by-product, which is often discarded as a waste. It would lead to a certain degree of harm to the environment. The aim of this study was to prepare the biochars with neem seed active substance extracted residues (NSASER) under the anaerobic pyrolysis conditions. The pyrolysis process was studied with different pyrolysis power (200W, 500W, 800W, 1100W and 1400W), and the performance of the prepared biochars was evaluated. The results showed that the required time was to complete the pyrolysis process that gradually decreased with pyrolysis power increased from 200 to 1400 W, and the final pyrolysis temperature was to complete the pyrolysis process that increased with pyrolysis power increased from 200 to 1400 W. The biochars yield decreased with pyrolysis power increased from 200 to 1400 W, and the biochars yield has the maximum value when the pyrolysis power was of 200W. And the prepared biochars still had some characteristics of the plant cell and kept uniform porous structure, which was beneficial to absorb the small molecule substance. The water content of the prepared biochars was 7.18±0.53, the ash content of the prepared biochars was 5.92±0.31 and the fixed carbon content of the prepared biochars was 81.27±0.89. Compared with the bamboo charcoal, the performance index of the prepared biochars was in according with National Standard of the People’s Republic of China GBT26913-2011 of the bamboo charcoal. The prepared biochars had a potential value in application.

  17. The Role of the Character Structure in Performer's Psychological Preparation to Concert Performance

    Science.gov (United States)

    Kurmanaev, Yermek M.

    2016-01-01

    The purpose of the research is to examine the correlation between performer's personal characteristics and the features of his/her artistic activity. The authors analyze various interpretations, proving that the character and temperament influence the properties of the performed musical material, including: the nature of sound; an attitude to the…

  18. The effect of combined preparation, probiotic and phytase on performance parameters and vitality of weaned piglets.

    Directory of Open Access Journals (Sweden)

    FESTIM SHYTAJ

    2014-06-01

    Full Text Available A combined preparation with probiotic Schaumalac F 80M BONVITAL 4b 1841 (2,5 x 1010 KBE Enterococcus faecium DSM 7134 and phytase was supplemented to a basal ration with 4%. The effects on growth performance on thirty five weaned piglets/each group were studied for thirty days experimental period. The supplementation of combined preparation improved slightly Daily Weight Gain (DWG, Feed Consumption (FC and Feed Conversion Ratio (FCR, kg feed/kg weight gain. At the end of experimental period, daily weight gain was increased 6% more and feed conversion ratio was decreased 3.4%, compared to the control group or without supplementation. The results indicate that the combined preparation may be less suppressive to the Escherichia coli. Overall a positive effect of the probiotic and phytase on growth performance was observed.

  19. Preparation and performance research of Ce-TiO2/KL ball photocatalysts

    Institute of Scientific and Technical Information of China (English)

    于晓娟; 熊领领; 马国平; 梁愿; 刘奎仁

    2014-01-01

    The Ce-TiO2/KL (diatomite) ball photocatalyst was prepared and characterized based on the pretreated diatomite. The re-sults showed that comparing with the crude diatomite, proper pretreatment could significantly improve its SiO2 purity and specific surface area. The surface of diatomite was clear with uniform pore structure and big pore size. With diatomite ball as carrier, the sup-ported Ce-TiO2/KL ball photocatalyst was prepared by sol-gel method. The photocatalytic performances of the supported Ce-TiO2/ KL ball and Ce-TiO2/KL powder photocatalysts under various preparation conditions were studied in view of photocatalytic degrada-tion rate of Rhodamine B (Rh B) solution. The degradation rate of the ball photocatalysts for Rh B reached 94.6% and could be re-used for many times, which showed much better photocatalytic performance and stability than powder photocatalysts.

  20. Extraction and Purification of Glucoraphanin by Preparative High-Performance Liquid Chromatography (HPLC)

    Science.gov (United States)

    Lee, Iris; Boyce, Mary C.

    2011-01-01

    A student activity that focuses on the isolation of glucoraphanin from broccoli using preparative high-performance liquid chromatography (HPLC) is presented here. Glucoraphanin is a glucosinolate, whose byproducts are known to possess anticancer properties. It is present naturally at high levels in broccoli and other "Brassica" vegetables. This…

  1. Extraction and Purification of Glucoraphanin by Preparative High-Performance Liquid Chromatography (HPLC)

    Science.gov (United States)

    Lee, Iris; Boyce, Mary C.

    2011-01-01

    A student activity that focuses on the isolation of glucoraphanin from broccoli using preparative high-performance liquid chromatography (HPLC) is presented here. Glucoraphanin is a glucosinolate, whose byproducts are known to possess anticancer properties. It is present naturally at high levels in broccoli and other "Brassica" vegetables. This…

  2. Preparation and Mechanical Performance of Rare Earth-Containing Composite Elastomer

    Institute of Scientific and Technical Information of China (English)

    邱关明; 周兰香; 张明; 中北里志; 井上真一; 冈本弘

    2001-01-01

    Rare earth-containing PSBR sheet was prepared by reaction of rare earth alkoxide with quaternary ammonium salt of pyridine modified SBR (PSBR) latex, and then it was blended with natural rubber (NR) to produce rare earth-containing composite elastomer. It is found that mechanical performance can be improved remarkably. Analyzed by infrared spectrometry (IR), differential scanning calorimetry (DSC) and cross-linking densitometry, the relationship between structure and performance was discussed.

  3. Congressional Districts

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This layer depicts the 114th Congressional Districts for the United States. Found within this layer is the listing of the 114th House of Representatives. Elected to...

  4. Wastewater Districts

    Data.gov (United States)

    Vermont Center for Geographic Information — The Wastewater districts layer is part of a larger dataset that contains administrative boundaries for Vermont's Agency of Natural Resources. The dataset includes...

  5. Wildlife Districts

    Data.gov (United States)

    Vermont Center for Geographic Information — The Wildlife Districts layer is part of a larger dataset contains administrative boundaries for Vermont's Agency of Natural Resources. The dataset includes feature...

  6. Warden Districts

    Data.gov (United States)

    Vermont Center for Geographic Information — This dataset is a representation overlay of warden (areas of responsibility). The Vermont Warden Districts layer is part of a dataset that contains administrative...

  7. Forestry Districts

    Data.gov (United States)

    Vermont Center for Geographic Information — The Forestry Districts layer is part of a dataset that contains administrative boundaries for Vermont's Agency of Natural Resources. This is a layer file which...

  8. Fisheries Districts

    Data.gov (United States)

    Vermont Center for Geographic Information — The Fisheries districts data layer is part of a larger dataset that contains administrative boundaries for Vermont's Agency of Natural Resources. The dataset...

  9. Park Districts

    Data.gov (United States)

    Vermont Center for Geographic Information — The Parks Districts layer is part of a dataset contains administrative boundaries for Vermont's Agency of Natural Resources. The dataset includes feature classes for...

  10. Preparation and influence of performance of anodic catalysts for direct methanol fuel cell

    Institute of Scientific and Technical Information of China (English)

    WANG Zhenbo; YIN Geping; SHI Pengfei

    2007-01-01

    This research aims at increasing the utilization of platinum-ruthenium alloy (Pt-Ru) catalysts and thus lowering the catalyst loading in anodes for methanol electrooxidation.The direct methanol fuel cell's (DMFC) anodic catalysts,Pt-Ru/C,were prepared by chemical reduction with a reducing agent added in two kinds of solutions under different circumstances.The reducing agent was added in hot solution with the protection of inert gases or just air,and in cold solution with inert gases.The catalysts were treated at different temperatures.Their performance was tested by cyclic voltammetry and potentiostatic polarization by utilizing their inherent powder microelectrode in 0.5 mol/L CH3OH and 0.5 mol/L H2SO4 solution.The structures and micro-surface images ofthe catalysts were determined and observed by X-ray diffraction and transmission electron microscopy,respectively.The catalyst prepared in inert gases showed a better catalytic performance for methanol electrooxidation than that prepared in air.It resulted in a more homogeneous distribution of the Pt-Ru alloy in carbon.Its size is small,only about 4.5 nm.The catalytic performance is affected by the order of the reducing agent added.The performance of the catalyst prepared by adding the reductant at constant temperature of the solution is better than that prepared by adding it in the solution at 0℃ and then heating it up to the reducing temperature.The structure of the catalyst was modified,and there was an increase in the conversion of ruthenium into the alloyed state and an increase in particle size with the ascension of heat treatment temperature.In addition,the stability of the catalyst was improved after heat treatment.

  11. Propellant Grade Hydrazine in Mono/Bi-propellant Thrusters: Preparation and Performance Evaluation

    Directory of Open Access Journals (Sweden)

    S. Krishnamachary

    2015-03-01

    Full Text Available Propellant grade hydrazine was prepared with 64 per cent yield and 95.5 per cent purity. Purity of the propellant grade hydrazine was determined using wet chemical, gas chromatographic (GC and eudiometric methods. It was observed that the compositions containing blends of hydrazine-methyl alcohol-ammonium nitrate and hydrazine-methyl alcohol-ammonium perchlorate were not found to be frozen even after cooling to -65 °C for 30 minutes. Mono and bi-propellant thrusters were designed and developed to demonstrate the performance of prepared propellant grade hydrazine as a promising rocket fuel. Five static tests with 22 N thruster and one static test with 1 N thruster were performed successfully in mono-propellant mode. The hurdles of chamber pressure oscillations were overcome by compact packing of the catalyst. The desired decomposition and chamber pressure were achieved. One static test was performed successfully with 60 N bi-propellant thruster. The desired chamber pressure and thrust were achieved. The combustion was smooth and C* achieved was higher than that of UH-25, N2O4 combination. The performance of prepared propellant grade hydrazine shows it as a promising rocket fuels.Defence Science Journal, Vol. 65, No. 1, January 2015, pp.31-38, DOI:http://dx.doi.org/10.14429/dsj.65.7986

  12. Assessing the Distribution of Fiscal and Personnel Resources across Schools. A Report Prepared for Twin Rivers Unified School District. SSFR Research Report #01 (TRUSD)

    Science.gov (United States)

    Chambers, Jay G.; Levin, Jesse; Brodziak, Iliana; Chan, Derek

    2010-01-01

    Using fiscal data provided by the finance office of the school district, and personnel data obtained from the California Basic Education Data System (maintained by the California Department of Education, or CDE), the authors present analyses to provide a foundation for local policymakers that may be used to assess whether there are inequities in…

  13. Preparation of carbon supported Pt-P catalysts and its electrocatalytic performance for oxygen reduction

    Energy Technology Data Exchange (ETDEWEB)

    Ma Juan [Institute of Chemical Power Sources, Soochow University, Suzhou 215006 (China); Tang Yawen; Yang Gaixiu; Chen Yu [College of Chemistry and Material Science, Nanjing Normal University, Nanjing 210097 (China); Zhou Qun [Institute of Chemical Power Sources, Soochow University, Suzhou 215006 (China); Lu Tianhong [College of Chemistry and Material Science, Nanjing Normal University, Nanjing 210097 (China); Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China); Zheng Junwei, E-mail: jwzheng@suda.edu.cn [Institute of Chemical Power Sources, Soochow University, Suzhou 215006 (China)

    2011-05-15

    The carbon supported PtP (PtP/C) catalysts were synthesized from Pt(NO{sub 3}){sub 2} and phosphorus yellow at the room temperature. The content of P in the PtP/C catalysts prepared with this method is high and the average size of the PtP particles is decreased with increasing the content of P. The electrocatalytic performances of the PtP/C catalysts prepared with this method for the oxygen reduction reaction (ORR) are better than that of the commercial Pt/C catalyst. The promotion action of P for enhancing the electrocatalytic performance of the PtP/C catalyst for ORR is mainly due to that Pt and P form the alloy and then the electron density of Pt is decreased.

  14. Preparation, characterization, and high performance of RuSe/C for direct methanol fuel cells

    Science.gov (United States)

    Serov, Alexey Alexandrovich; Min, Myoungki; Chai, Geunseok; Han, Sangil; Kang, Soonki; Kwak, Chan

    RuSe/C catalysts prepared by different methods have been tested for oxygen reduction and the results analyzed based on the active species and particle size distribution. Inorganic precursor methods exhibit higher catalytic performance than the carbonyl method. Selenious acid is an excellent inorganic precursor. X-ray photoelectron spectra indicate that selenium in a high oxidation state is more active than that with zero valence. The effect of operating conditions is analyzed for catalysts prepared by the inorganic precursor method. The optimum heat-treatment temperature for both active phase formation and particle size distribution is 300 °C. A performance of 62 mW cm -2 at 80 °C is obtained using 80 wt.% RuSe/C in the cathode.

  15. INVESTIGATION OF SOFTENING AGENT PREPARATION AND PERFORMANCE OF HANDMADE ECOCOMPOSITES WITH CONIFEROUS WOOD AND BASALT FIBERS

    Institute of Scientific and Technical Information of China (English)

    GuangjianWang; DekuShang; KailiangZhang; LinnaHu; ZhenhuaGuo

    2004-01-01

    In this investigation, basalt mineral fiber softening agent was prepared in order to obtain desirable flexible performance. Stability and physical chemistry natures of softening agent were evaluated by particle size distribution, dilution, storage and folding endurance etc. Constitutes of basalt and wood fibers were determined by energy dispersion analysis X-ray which served as an accessory of scanning electron microscopy (SEM-EDAX). Naturally degradable ecocomposite was prepared by basalt and wood fibers. The results of SEM observation illustrated that the wood and basalt fibers were blended uniformly. The impact factors of beating degree, content of wood fibers and adhesive etc. were discussed. The structure of the naturally degradable ecocomposite was contrasted with that of pure wood fibers and the cause of excellent filtration performance was analyzed. Compared with traditional methods, it was of saving wood resource, a large amount of water and reducing second pollution. As a consequence, the ecocomposite harmonized with environment and accorded with requirement of benignly friendly environment.

  16. Preparing the Self for Team Entry: How Relational Affirmation Improves Team Performance

    OpenAIRE

    Lee, Julia J; Gino, Francesca; Cable, Daniel M.; Bradley R. Staats

    2016-01-01

    Working in teams often leads to productivity loss because the need to feel accepted prevents individual members from making a unique contribution to the team in terms of the information or perspective they can offer. Drawing on self-affirmation theory, we propose that pre-team relational self-affirmation can prepare individuals to contribute to team creative performance more effectively. We theorize that relationally-affirming one’s self-views increases general feelings of being socially valu...

  17. Building Energy Storage Panel Based on Paraffin/Expanded Perlite: Preparation and Thermal Performance Study

    Directory of Open Access Journals (Sweden)

    Xiangfei Kong

    2016-01-01

    Full Text Available This study is focused on the preparation and performance of a building energy storage panel (BESP. The BESP was fabricated through a mold pressing method based on phase change material particle (PCMP, which was prepared in two steps: vacuum absorption and surface film coating. Firstly, phase change material (PCM was incorporated into expanded perlite (EP through a vacuum absorption method to obtain composite PCM; secondly, the composite PCM was immersed into the mixture of colloidal silica and organic acrylate, and then it was taken out and dried naturally. A series of experiments, including differential scanning calorimeter (DSC, scanning electron microscope (SEM, best matching test, and durability test, have been conducted to characterize and analyze the thermophysical property and reliability of PCMP. Additionally, the thermal performance of BESP was studied through a dynamic thermal property test. The results have showed that: (1 the surface film coating procedure can effectively solve the leakage problem of composite phase change material prepared by vacuum impregnation; (2 the optimum adsorption ratio for paraffin and EP was 52.5:47.5 in mass fraction, and the PCMP has good thermal properties, stability, and durability; and (3 in the process of dynamic thermal performance test, BESP have low temperature variation, significant temperature lagging, and large heat storage ability, which indicated the potential of BESP in the application of building energy efficiency.

  18. Building Energy Storage Panel Based on Paraffin/Expanded Perlite: Preparation and Thermal Performance Study.

    Science.gov (United States)

    Kong, Xiangfei; Zhong, Yuliang; Rong, Xian; Min, Chunhua; Qi, Chengying

    2016-01-25

    This study is focused on the preparation and performance of a building energy storage panel (BESP). The BESP was fabricated through a mold pressing method based on phase change material particle (PCMP), which was prepared in two steps: vacuum absorption and surface film coating. Firstly, phase change material (PCM) was incorporated into expanded perlite (EP) through a vacuum absorption method to obtain composite PCM; secondly, the composite PCM was immersed into the mixture of colloidal silica and organic acrylate, and then it was taken out and dried naturally. A series of experiments, including differential scanning calorimeter (DSC), scanning electron microscope (SEM), best matching test, and durability test, have been conducted to characterize and analyze the thermophysical property and reliability of PCMP. Additionally, the thermal performance of BESP was studied through a dynamic thermal property test. The results have showed that: (1) the surface film coating procedure can effectively solve the leakage problem of composite phase change material prepared by vacuum impregnation; (2) the optimum adsorption ratio for paraffin and EP was 52.5:47.5 in mass fraction, and the PCMP has good thermal properties, stability, and durability; and (3) in the process of dynamic thermal performance test, BESP have low temperature variation, significant temperature lagging, and large heat storage ability, which indicated the potential of BESP in the application of building energy efficiency.

  19. Plasmonic photosensitization of polyaniline prepared by a novel process for high-performance flexible photodetector.

    Science.gov (United States)

    Barman, Tapan; Pal, Arup R

    2015-02-01

    We report the synthesis of a polyaniline (PAni)-gold nanoparticle (AuNP) composite thin film in a single step. A flexible high-performance visible photodetector is constructed using PAni-AuNP composite with low loading of AuNP, and optoelectronic properties of the device are evaluated. The present study demonstrates that a plasmonic hybrid nanocomposite prepared by a single-step novel plasma-based dry process could solve the low lifetime and performance-related issues of organic optoelectronic devices.

  20. Mental fatigue and temporal preparation in simple reaction-time performance.

    Science.gov (United States)

    Langner, Robert; Steinborn, Michael B; Chatterjee, Anjan; Sturm, Walter; Willmes, Klaus

    2010-01-01

    Performance decrements attributed to mental fatigue have been found to be especially pronounced in tasks that involve the voluntary control of attention. Here we explored whether mental fatigue from prolonged time on task (TOT) also impairs temporal preparation for speeded action in a simple reaction-time task. Temporal preparation is enabled by a warning signal presented before the imperative stimulus and usually results in shorter reaction time (RT). When the delay between warning and imperative stimuli - the foreperiod (FP) - varies between trials, responses are faster with longer FPs. This pattern has been proposed to arise from either voluntary attentional processes (temporal orienting) or automatic trial-to-trial learning (trace conditioning). The former account suggests a selective RT increase on long-FP trials with fatigue; the latter account suggests no such change. Over a work period of 51 min, we found the typical increase in overall RT but no selective RT increase after long FPs. This additivity indicates that TOT-induced mental fatigue generally reduces cognitive efficiency but leaves temporal preparation under time uncertainty unaffected. We consider this result more consistent with the trace-conditioning account of temporal preparation.

  1. An analysis of high-performing science students' preparation for collegiate science courses

    Science.gov (United States)

    Walter, Karen

    This mixed-method study surveyed first year high-performing science students who participated in high-level courses such as International Baccalaureate (IB), Advanced Placement (AP), and honors science courses in high school to determine their perception of preparation for academic success at the collegiate level. The study used 52 students from an honors college campus and surveyed the students and their professors. The students reported that they felt better prepared for academic success at the collegiate level by taking these courses in high school (pstudent GPA with honors science courses (n=55 and Pearson's r=-0.336), while AP courses (n=47 and Pearson's r=0.0016) and IB courses (n=17 and Pearson's r=-0.2716) demonstrated no correlation between perception of preparation and GPA. Students reported various themes that helped or hindered their perception of academic success once at the collegiate level. Those themes that reportedly helped students were preparedness, different types of learning, and teacher qualities. Students reported in a post-hoc experience that more lab time, rigorous coursework, better teachers, and better study techniques helped prepare them for academic success at the collegiate level. Students further reported on qualities of teachers and teaching that helped foster their academic abilities at the collegiate level, including teacher knowledge, caring, teaching style, and expectations. Some reasons for taking high-level science courses in high school include boosting GPA, college credit, challenge, and getting into better colleges.

  2. Nanocellulose 3, 5-Dimethylphenylcarbamate Derivative Coated Chiral Stationary Phase: Preparation and Enantioseparation Performance.

    Science.gov (United States)

    Zhang, Xiaoli; Wang, Litao; Dong, Shuqing; Zhang, Xia; Wu, Qi; Zhao, Liang; Shi, Yanping

    2016-05-01

    Nanocrystalline cellulose (NCC) with high surface area and high ordered crystalline structure was prepared from microcrystalline cellulose (MCC) under the hydrolysis of sodium hypochlorite. NCC was further reacted with 3,5-dimethylphenyl isocyanate to obtain the nanocellulose derivative, and then coated successfully on the surface of silica gel to a prepared NCC-coated chiral stationary phase (CSP) as a new kind of chiral separation material. Similarly, MCC derivative-coated CSP was also prepared as contrast. The chiral separation performance of NCC-based CSP was evaluated and compared with MCC-based CSP by high-performance liquid chromatography. Moreover, the effects of the alcohol modifiers, mobile phase additives, and flow rates on chiral separations were investigated in detail. The results showed that 10 chiral compounds were separated on NCC-based CSP with better peak shape and higher column efficiency than MCC-based CSP, which confirmed that NCC-based CSP was a promising packing material for the resolution of chiral compounds.Chirality 28:376-381, 2016. © 2016 Wiley Periodicals, Inc.

  3. Modelling district nurse expertise.

    Science.gov (United States)

    Burke, Michelle

    2014-12-01

    As changes in society and health provision mean that one in four people over the age of 75 will require nursing care at home, pre-registration adult nurse education increasingly prepares student nurses for a future career within the community. District nurses undertake complex, multidimensional health and social assessments and care in a non-clinical setting and work in partnership with patients and their significant others to promote practical and psychological coping mechanisms and self-care. The district nurse's first assessment visit is key to developing a therapeutic partnership and it is often during this visit that expertise in district nursing practice emerges. The holistic, contextual and dynamic aspects of nursing in the home setting can make district nursing expertise difficult to illustrate and demonstrate within the classroom setting. This article explores the ways in which an understanding of expertise development theory can enable the tacit expertise that occurs within the first assessment visit to be made visible to student nurses, using simulation and expert narrative as a pedagogical strategy.

  4. Bio-medical waste management: situational analysis & predictors of performances in 25 districts across 20 Indian States

    Directory of Open Access Journals (Sweden)

    INCLEN Program Evaluation Network (IPEN study group, New Delhi, India

    2014-01-01

    Full Text Available Background & objectives: A legislative framework for bio-medical waste management (BMWM was established in the country more than a decade ago. Though some studies have identified gaps at local levels, no systematic effort was done to collect data from different parts of the country. The objective of this nationwide study was to document existing resources, infrastructure and practices related to BMWM across the study districts. Methods: The study was conducted in 25 districts spread over 20 States of India including urban and rural areas. Primary (n=388, secondary (n=25 and tertiary care (n=24 health facilities from public (n=238 and private (n=199 sector were assessed and scored for the state of BMWM through 9 items representing system capacity, availability of resources and processes in place. Health facilities were assigned into one of the three categories (Red, Yellow and Green based on the cumulative median scores. Results: Around 82 per cent of primary, 60 per cent of secondary and 54 per cent of tertiary care health facilities were in the ′RED′ category. Multivariate analysis indicated that charts at the point of waste generation, availability of designated person, appropriate containers and bags, availability of functional needle destroyers, availability of personal protective gears, segregation of waste at point of generation and log book maintenance were independently (OR-between 1.2-1.55; P <0.03 or less associated with better BMWM system in the health facilities. This was true for both rural-urban and public or private health facilities. Interpretation & conclusions: The study highlighted the urgent need for greater commitments at policy and programme levels for capacity building, and resource investments in BMWM.

  5. Gender Differences in Introductory University Physics Performance: The Influence of High School Physics Preparation and Affect

    Science.gov (United States)

    Hazari, Zahra

    2006-12-01

    The attrition of females studying physics after high school has been a continuing concern for the physics education community. If females are well prepared, feel confident, and do well in introductory college physics, they may be inclined to study physics further. This quantitative study uses HLM to identify factors from high school physics preparation (content, pedagogy, and assessment) and the affective domain that predict female and male performance in introductory college physics. The study includes controls for student demographic and academic background characteristics, and the final dataset consists of 1973 surveys from 54 introductory college physics classes. The results highlight high school physics and affective experiences that differentially predict female and male performance. These experiences include: learning requirements, computer graphing/analysis, long written problems, everyday world examples, community projects cumulative tests/quizzes, father's encouragement, family's belief that science leads to a better career, and the length of time students believe that high school physics would help in university physics. There were also experiences that similarly predict female and male performance. The results paint a dynamic picture of the factors from high school physics and the affective domain that influence the future physics performance of females and males. The implication is that there are many aspects to the teaching of physics in high school that, although widely used and thought to be effective, need reform in their implementation in order to be fully beneficial to females and/or males in college.

  6. {sup 99}Mo/{sup 99m}Tc generators performances prepared from zirconium molybdate gels

    Energy Technology Data Exchange (ETDEWEB)

    Monroy-Guzman, Fabiola; Diaz-Archundia, Laura Veronica; Hernandez-Cortes, Sabino [Instituto Nacional de Investigaciones Nucleares, Estado de Mexico (Mexico)]. E-mail: fmg@nuclear.inin.mx

    2008-07-01

    {sup 99m}Tc may be produced from {sup 99}Mo/{sup 99m}Tc zirconium molybdate gel generators. These gels are part of the generator matrix and their chemical and physical characteristics directly influence the generator performances. In this work zirconium molybdate gels were synthesized under different preparation conditions and characterized by TGA, IR and INAA. Our goal was to investigate and correlate generator performance with the physical-chemical properties of the gel. The two factors studied were the molybdate solution pH and the preparation conditions of the zirconyl salt solutions. Several polymolybdate and zirconium species can be formed in solution which can inhibit or favor the zirconium molybdate gel formation or the insoluble polymolybdate-rich and zirconium oxy-hydroxide phases. The {sup 99}Mo/{sup 99m}Tc gel generator performance is directly correlated with gel structures. More regular network gels present lower generator performances compared to gels with more flexible random framework. The physico-chemical properties of the gels as well as their behavior as technetium-99m generators are presented and discussed. (author)

  7. Preparation and Photocatalytic Performance of MWCNTs/TiO2 Nanocomposites for Degradation of Aqueous Substrate

    Directory of Open Access Journals (Sweden)

    Qiannan Duan

    2016-01-01

    Full Text Available In this study, multiwalled carbon nanotubes (MWCNTs/TiO2 nanocomposites were obtained by constant volumetric wet impregnation processes. The prepared catalysts were characterized by scanning electron microscopy (SEM and X-ray photoelectron spectroscopy (XPS. The effect of reaction conditions on photocatalytic performance of the catalysts was investigated by the degradation of methyl orange (MO under UV irradiation, in a new type of reactor with unique structure. The results showed that the prepared nanocomposite exhibited higher MO degradation efficiency than that of pure nano-TiO2. Besides, in batch experiments of influencing factors, including ionic strength, oxidant amount, and response times, the presence of H2O2 would contribute to increasing the MO degradation rate of MWCNTs/TiO2 samples. Ionic concentration and long reaction times are adverse to the MO degradation in the processes.

  8. Studies Performed in Preparation for the Spallation Neutron Source Accumulator Ring Commissioning

    CERN Document Server

    Cousineau, Sarah M; Henderson, Stuart; Holmes, Jeffrey Alan; Plum, Michael

    2005-01-01

    The Spallation Neutron Source accumulator ring will compress 1.5?1014, 1 GeV protons from a 1 ms bunch train to a single 695 ns proton bunch for use in neutron spallation. Due to the high beam power, unprecedented control of beam loss will be required in order to control radiation and allow for hands-on maintenance in most areas of the ring. A number of detailed investigations have been performed to understand the primary sources of beam loss and to predict and mitigate problems associated with radiation hot spots in the ring. The ORBIT particle tracking code is used to perform realistic simulations of the beam accumulation in the ring, including detailed modeling of the injection system, transport through the measured magnet fields including higher order multipoles, and beam loss and collimation. In this paper we present the results of a number of studies performed in preparation for the 2006 commissioning of the accumulator ring.

  9. Study of special performance and volume training loadings at swimmers in the year preparation

    Directory of Open Access Journals (Sweden)

    Balamutova N.M.

    2014-01-01

    Full Text Available Purpose : to study the dynamics of the special performance and volume of training load during annual training swimmers. Material / Methods : The study involved 14 teams of students of Kharkiv universities. All swimmers are of high qualification. Motor tests of special performance swimmers, functional tests were used to confirm the effectiveness of the training process. Results : The dynamics of special performance indicators and volume of training load of highly qualified swimmers in the annual cycle of training. Determined part of aerobic (58.3 %, aerobic- anaerobic special (34.5%, anaerobic- glycolytic (5.5%, anaerobic- alactate (1.7% loadings in the direction of total training load for the academic year. Conclusions : In preparing swimmers stayer is the most appropriate single-cycle construction of the annual cycle, and for swimmers, sprinters should be based on two-cycle version of the load distribution.

  10. Evaluation of the effect of Block Level Awareness Campaign on performance indicators of National Leprosy Elimination Program in Vadodara district, Gujarat, India

    Directory of Open Access Journals (Sweden)

    Lipy K Shukla

    2015-01-01

    Full Text Available Background: Leprosy is probably the oldest disease afflicting mankind and a public health problem for centuries. Many cases are hidden or undiagnosed, especially due to social stigma, and neglect of painless patches. Between years 2001 and 2005, during which time active surveillance for detection of leprosy was in practice, a steep fall in the prevalence rate (PR of leprosy was observed. However, during later years, leprosy program discontinued active surveillance for detection of leprosy cases. Presently block level awareness campaign (BLAC is a special measure undertaken in a campaign mode during September-November in priority areas, (PR > 1/10000 population, during which information, education and communication (IEC activities and active surveillance of leprosy cases is done. Aims: To evaluate the effect of Block Level Awareness Campaign on performance indicators of national leprosy elimination program (NLEP in Vadodara district. Methods: The campaign was carried out for 6 days in 12 talukas of Vadodara district by the district leprosy office, Vadodara. Trained teams of health workers carried out information, education and communication (IEC activity and active surveillance by undertaking house to house survey in each primary health centre (PHC area. Suspected cases were identified by the team and confirmed clinically by medical officers in the primary health centre of the corresponding areas. A district nucleus team (DNT validated these confirmed cases. These data were compared with the district′s national leprosy eradication programme (NLEP data for the same year, 2012 and the previous year, 2011. Results: A total of 1,574,586 persons, comprising 76%of the population surveyed, were screened for leprosy, which resulted in detection of 358 clinically confirmed new cases of leprosy, out of which 225 (62.8% were paucibacillary (PB and 133 (37.2% were multibacillary (MB leprosy. Of these cases, 14 (4% had deformities, and 37 (10.3% were

  11. Preparation and performance of thermal insulation energy saving coating materials for exterior wall.

    Science.gov (United States)

    Wang, Fei; Liang, Jinsheng; Tang, Qingguo; Chen, Gong; Chen, Yalei

    2014-05-01

    Nano zinc oxide with a high refractive index has good thermal reflection performance, hollow glass microspheres have good thermal reflection and insulation performance, and sepiolite nanofibers with many nanostructural pores have good thermal insulation performance. The dispensability of nano zinc oxide in coating materials was improved by optimizing surface silane coupling agent modification process, leading to the good thermal reflection performance. The thermal insulation performance was improved by hollow glass microspheres and sepiolite nanofibers. On this basis, the thermal insulation coating materials were prepared by exploring the effect of amount, complex mode, and other factors of the above three kinds of functional fillers on the thermal reflection and insulation performance of coating materials. The results showed that the surface modification effect of nano zinc oxide was the best when the silane coupling agent addition was 6%. The reflection and insulation performance of the coatings were the best when the additions of modified nano zinc oxide, hollow glass microspheres, and sepiolite nanofibers were 3%, 4%, and 4%, respectively. Compared with the control coating materials, the thermal insulation effect was improved obviously, which was evaluated by the -13.5 degrees C increase of maximum temperature difference between the upper and the lower surfaces.

  12. Enhancing assertiveness in district nurse specialist practice

    OpenAIRE

    Green, J.

    2016-01-01

    District nurse (DN) care delivery has undergone substantial change in recent years due to changing demographics and service delivery demands that have called for a move of care delivery from secondary to primary care. The title District Nurse is recorded with the Nursing and Midwifery Council (NMC) on completion of the Specialist Practice Qualification in District Nursing (SPQ DN), which purports to be a 'transformational' course that prepares future caseload holders to manage their team and ...

  13. Geothermal district heating systems

    Science.gov (United States)

    Budney, G. S.; Childs, F.

    1982-06-01

    Ten district heating demonstration projects and their present status are described. The projects are Klamath County YMCA, Susanville District Heating, Klamath Falls District Heating, Reno Salem Plaza Condominium, El Centro Community Center Heating/Cooling, Haakon School and Business District Heating, St. Mary's Hospital, Diamond Ring Ranch, Pagosa Springs District Heating, and Boise District Heating.

  14. Comparison of load-fatigue performance of posterior ceramic onlay restorations under different preparation designs.

    Science.gov (United States)

    Kois, Dean E; Chaiyabutr, Yada; Kois, John C

    2012-06-01

    The objective of this study was to evaluate the load-fatigue performance of posterior ceramic onlay restorations relative to two variables: preparation design (with or without buccal veneers); and the existing amount of tooth structure (non-worn tooth, worn tooth). Sixty extracted third molars were divided into five groups. One group received a mesial-occlusal-distal (MOD) gold onlay restoration (control). The other four experimental groups were prepared for ceramic onlay restorations. Two of the groups additionally received 2-mm occlusal reduction to simulate occlusal wear. All restored teeth were subjected to thermocycling prior to fatigue testing. A fatigue load of 150 N was applied on the occlusal surface at a frequency of 1.2 hz, at an angle of 135 degrees to the long axis of the tooth. Specimen failure was defined as the occurrence of crack propagation in the luting cement layer. This was monitored by the strain gauge on the specimen. All specimens restored on worn tooth had significantly lower fatigue failure cycle counts than those of non-worn tooth. The fracture mode analysis revealed that ceramic fracture tended to be demonstrated only in the group of worn tooth groups. The addition of a buccal veneer component had no significant effect on the load-fatigue performance of posterior ceramic onlay restorations, but the existing amount of tooth structure did have a significant effect on the load-fatigue performance of posterior ceramic onlay restorations. Catastrophic failures (ceramic fracture) occurred only in the group of worn tooth.

  15. Characterization and performance assessment of solid dispersions prepared by hot melt extrusion and spray drying process.

    Science.gov (United States)

    Agrawal, Anjali M; Dudhedia, Mayur S; Patel, Ashwinkumar D; Raikes, Michelle S

    2013-11-30

    The present study investigated effect of manufacturing methods such as hot melt extrusion (HME) and spray drying (SD) on physicochemical properties, manufacturability, physical stability and product performance of solid dispersion. Solid dispersions of compound X and PVP VA64 (1:2) when prepared by SD and HME process were amorphous by polarized light microscopy, powder X-ray diffractometry, and modulated differential scanning calorimetry analyses with a single glass transition temperature. Fourier transform infrared (FT-IR) and Raman spectroscopic analyses revealed similar molecular level interactions between compound X and PVP VA64 as evident by overlapping FT-IR and FT Raman spectra in SD and HME solid dispersions. The compactibility, tabletability, disintegration and dissolution performance were similar for solid dispersions prepared by both processing techniques. Differences in material properties such as surface area, morphological structure, powder densities, and flow characteristics were observed between SD and HME solid dispersion. The SD solid dispersion was physically less stable compared to HME solid dispersion under accelerated stability conditions. Findings from this study suggest that similar product performance could be obtained if the molecular properties of the solid dispersion processed by two different techniques are similar. However differences in material properties might affect the physical stability of the solid dispersions.

  16. Preparation and electrochemical performance of nanosized Co3O4 via hydrothermal method

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The hydrotalcite-type cobalt compounds were prepared through oxidation of Co(OH)2 gel using NH4OH as precipitating agent and H2O2 as oxidant. These hydrotalcite-type cobalt compounds were transformed into Co3O4 through hydrothermal decomposition with nanostructural deformation. The precursor and product were characterized by Fourier-transform infrared(FT-IR)spectrum, X-ray diffractometry(XRD) and transmission electron microscopy(TEM). The electrochemical performances of as-prepared nanosized Co3O4 as anode materials in lithium-ion batteries were tested by charge-discharge test in the voltage range of 0-3.0 V. The influence of morphology of Co3O4 particle on the capacity and cycling performance was studied. The results show that the shape and size of the final product can be controlled by altering cobalt sources. The irregular cubic Co3O4 with the average particle size of about 10 nm shows the best electrochemical performance. After 10 charge-discharge cycles, the specific charge capacity retains 555 mA·h/g.

  17. RECENT DEVELOPMENTS IN HETEROGENEOUS IONEXCHANGE MEMBRANE: PREPARATION, MODIFICATION, CHARACTERIZATION AND PERFORMANCE EVALUATION

    Directory of Open Access Journals (Sweden)

    I. G. WENTEN

    2016-07-01

    Full Text Available Ion-exchange membranes (IEMs have been used in different processes and applications and have shown the advantages over other comparative processes. The extensive applications of IEMs in many areas have necessitated the improvement in their properties to achieve better performance and lower cost. As the first commercialized IEMs, heterogeneous membranes face the challenge to improve their lower selectivity and conductivity which associated to the higher heterogeneity. Recently, development of the heterogeneous IEMs is steadily growing which is driven by the need to obtain IEMs with better electrochemical properties, lower production cost, and easier preparation procedure. Additive blending, membrane surface modifications, and post-treatment are typical methods used to improve heterogeneous IEMs characteristics. The methods give the improvement in electro-chemical characteristics of heterogeneous membranes and provide the possibility to produce heterogeneous IEMs with comparable performance to homogeneous ones. In this paper, preparation, characterization, and performance of heterogenous IEMs are reviewed. In addition, recent progress on IEMs modifications is pointed out.

  18. Preparation and Performance of a Fixed Bed Catalyst for the Oxidation of Sodium Mercaptides

    Directory of Open Access Journals (Sweden)

    Heming Wang

    2014-07-01

    Full Text Available The activated-carbon supported cobalt pthalocyanine as a fixed bed catalyst (CoPc/C was prepared by impregnation method and its performance on the oxidation of sodium mercaptides in light oil sweetening was investigated. The FTIR, XRD, and SEM analysis indicated that the active component dispersed well on the carrier and the results of the TG analysis showed that CoPc/C has good thermostability. It was tested that the prepared catalyst has a high catalytic activity towards sodium mercaptides. The removal rate of n-C4H9SNa was up to 100 % and for t-C4H9SNa, was 87.5% at a reaction time of 30 min. With the reaction temperature raised from 20 °C to 60 °C at intervals of ten degrees, the oxidation rate increased obviously, especially in the first ten minutes. A kinetic model mainly related to the transfer process was supposed. The catalyst CoPc/C had a good anti-loss performance of the active component both in water and alkali liquor when used. © 2014 BCREC UNDIP. All rights reservedSubmitted: 20th June 2013; Revised: 1st March 2014; Accepted: 22nd March 2014[How to Cite: Heming, W., Xianshang, L., Lijun, Z., Yulu, Z., Daohong, X., (2014. Preparation and Performance of a Fixed Bed Catalyst for the Oxidation of Sodium Mercaptides. Bulletin of Chemical Reaction Engineering & Catalysis, 9 (2: 87-92.(doi:10.9767/bcrec.9.2.5113.87-92][Permalink/DOI: http://dx.doi.org/10.9767/bcrec.9.2.5113.87-92] 

  19. Formulation and Performance of Novel Energetic Nanocomposites and Gas Generators Prepared by Sol-Gel Methods

    Energy Technology Data Exchange (ETDEWEB)

    Clapsaddle, B J; Zhao, L; Prentice, D; Pantoya, M L; Gash, A E; Satcher Jr., J H; Shea, K J; Simpson, R L

    2005-03-24

    In the field of composite energetic materials, properties such as ingredient distribution, particle size, and morphology affect both sensitivity and performance. Since the reaction kinetics of composite energetic materials are typically controlled by the mass transport rates between reactants, one would anticipate new and potentially exceptional performance from energetic nanocomposites. We have developed a new method of making nanostructured energetic materials, specifically explosives, propellants, and pyrotechnics, using sol-gel chemistry. A novel sol-gel approach has proven successful in preparing nanostructured metal oxide materials. By introducing a fuel metal, such as aluminum, into the nanostructured metal oxide matrix, energetic materials based on thermite reactions can be fabricated. Two of the metal oxides are tungsten trioxide and iron(III) oxide, both of which are of interest in the field of energetic materials. Due to the versatility of the preparation method, binary oxidizing phases can also be prepared, thus enabling a potential means of controlling the energetic properties of the subsequent nanocomposites. Furthermore, organic additives can also be easily introduced into the nanocomposites for the production of nanostructured gas generators. The resulting nanoscale distribution of all the ingredients displays energetic properties not seen in its micro-scale counterparts due to the expected increase of mass transport rates between the reactants. The unique synthesis methodology, formulations, and performance of these materials will be presented. The degree of control over the burning rate of these nanocomposites afforded by the compositional variation of a binary oxidizing phase will also be discussed. These energetic nanocomposites have the potential for releasing controlled amounts of energy at a controlled rate. Due to the versatility of the synthesis method, a large number of compositions and physical properties can be achieved, resulting in

  20. Preparation, characterization, and catalytic performance of Ta-HMS mesoporous molecular sieve

    Science.gov (United States)

    Li, Xuefeng; Zhang, Like; Gao, Huanxin; Chen, Qingling

    2016-08-01

    Various Ta-HMS (hexagonal mesoporous silica) samples with different Ta content were hydrothermally prepared and characterized by XRD, N2-adsorption, ICP-AES, FTIR, and UV-Vis spectroscopy. The catalytic performance of the samples was also evaluated in the epoxidation of cyclohexene with cumene hydroperoxide as oxidant. The regularity of mesoporous structure decreases while more extraframe Ta ions are formed with increasing the Ta content. Ta-HMS with Ta/Si ratio of 0.015 shows the highest conversion and selectivity in the studied epoxidation reaction. The catalyst can be used for three times without significant activity loss.

  1. Study on preparation and performances of CDPVC/Ag3PO4 composite photocatalyst

    Directory of Open Access Journals (Sweden)

    Peng WANG

    2016-04-01

    Full Text Available PVC/Ag3PO4 composites are prepared by solution-dipping method, and the as-prepared composites are heat-treated to release HCl from PVC molecules to obtain conjugated derivative of PVC/Ag3PO4(CDPVC/Ag3PO4 composites. The CDPVC/Ag3PO4 composites are characterized by XRD, SEM, UV-vis DRS, PL and XPS. The effects of preparation conditions on the visible-light photocatalytic performances of CDPVC/Ag3PO4 composites are investigated by evaluating the decomposition of methyl orange under visible light irradiation. The results reveal that the modification of CDPVC is beneficial to the dispersion of Ag3PO4 particles, and it can obviously improve the absorbance of the CDPVC/Ag3PO4 composites in the range of visible light and the charge separation efficiency. The CDPVC/Ag3PO4 composites exhibit excellent visible-light photocatalytic acitivity and stability when the mass percentage of PVC to Ag3PO4, heat-treatment temperature and time are 0.03%, 130 ℃, and 2 h, respectively.

  2. Preparation of Silica Aerogel and Its Adsorption Performance to Organic Molecule

    Directory of Open Access Journals (Sweden)

    Hong-xin Shi

    2014-01-01

    Full Text Available Hydrophobic and lipophilic silica aerogel was prepared from water-glass by gelling, aging, silylation, and drying under atmospheric pressure and characterized by FT-IR and SEM. The effect of preparation process on aerogel density and the aerogel density on contact angle of water on it were investigated in detail. pH 6 is most beneficial to shorten gelling time and to obtain the lowest density of silica aerogel. Increasing TEOS concentration of aging solution to 25 v% could decrease aerogel density to 0.093 g/cm3. The silica aerogel exhibits good hydrophobicity even though its density is 0.30 g/cm3. There are few changes in their adsorption capacities after 3 cycles of adsorption-desorption. The adsorption performance of the silica aerogel to organic solvent in water is different from in pure solvents. The critical surface tension (γC of the silica aerogel prepared here is about 30.8 mN/m. If the surface tension of aqueous solvent solution (γ is greater than γC, it will wet the aerogel surface partially. If γ  ≤  γC, the solution will wet all aerogel surface and be adsorbed well. This work delivers us a method to adsorb solvents from their waste water by adjusting the surface tension of the waste water to lower than γC of the adsorbent.

  3. Numerical modelling and experimental measurements for a low-temperature district heating substation for instantaneous preparation of DHW with respect to service pipes

    DEFF Research Database (Denmark)

    Brand, Marek; Thorsen, Jan Eric; Svendsen, Svend

    2012-01-01

    as much as possible. This requires a review and improvement of a DH network, in-house substations, and the whole domestic hot water (DHW) supply system, with the focus on user comfort, hygiene, overall cost and energy efficiency. This paper describes some practical approaches to the implementation of low......-temperature district heating (LTDH) with an entry-to-substation temperature around 50 °C. To this end we developed a numerical model for an instantaneous LTDH substation that takes into consideration the effect of service pipes. The model has been verified and can be used for the further optimization of the whole...

  4. Elaborately prepared hierarchical structure titanium dioxide for remarkable performance in lithium storage

    Science.gov (United States)

    Tian, Qinghua; Luo, Dong; Li, Xiaowei; Zhang, Zhengxi; Yang, Li; Hirano, Shin-ichi

    2016-05-01

    Titanium dioxide (TiO2) has been considered to be a promisingly alternative anode material for lithium-ion batteries and thus attracted wide research interest. But, its practical application in lithium-ion batteries is seriously impeded by low capacity and poor rate capability. In the present work, the electrochemical performance of TiO2 is significantly improved by elaborately fabricating hierarchical structures. These as-prepared four hierarchical structure TiO2 assembled by different building blocks (TO2-2 h, TO2-6 h, TO2-18 h and TO2-24 h) all exhibit impressed performance. More importantly, the TO2-6 h constructed by curved nanosheets exhibits the best performance, delivering a capacity of 231.6 mAh g-1 at 0.2C after 200 cycles, and capacities of 187.1 and 129.3 mAh g-1 at 1 and 10C after even 1200 cycles, respectively. The results indicated that design and fabrication of hierarchical structure is an effective strategy for significantly improving the electrochemical performance of TiO2 electrodes, and the electrochemical performance of hierarchical structure TiO2 is heavily dependent on its building blocks. It is suggested that thus excellent electrochemical performance may make TiO2-6 h a promising anode material for advanced lithium-ion batteries with high capacity, good rate capability and long life.

  5. An Efficient Protocol for Preparation of Gallic Acid from Terminalia bellirica (Gaertn.) Roxb by Combination of Macroporous Resin and Preparative High-Performance Liquid Chromatography.

    Science.gov (United States)

    Zou, Denglang; Chen, Tao; Chen, Chen; Li, Hongmei; Liu, Yongling; Li, Yulin

    2016-08-01

    In this article, macroporous resin column chromatography and preparative high-performance liquid chromatography were applied for preparation of gallic acid from Terminalia bellirica (Gaertn.) Roxb. In the first step, six kinds of resins were investigated by adsorption and desorption tests and AB-8 macroporous resin was selected for the enrichment of gallic acid. As a result, 20 g of gallic acid at a purity of 71% could be separated from 100 g of crude extract in which the content of gallic acid was 16.7% and the recovery of gallic acid reached 85.0%. In the second step, preparative high-performance liquid chromatography was selected to purify gallic acid. As a result, 640 mg of gallic acid at a purity of 99.1% was obtained from 1 g of sample in 35 min. The results demonstrated that macroporous resin coupled with preparative high-performance liquid chromatography was suitable for preparation of gallic acid from T. bellirica (Gaertn.) Roxb.

  6. Preparation and performance of novel thermally stable polyamide/PPENK composite nanofiltration membranes

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Lijie [State Key Laboratory of Fine Chemical, Dalian 116024 (China); Liaoning High Performance Polymer Engineering Research Center, Dalian 116024 (China); Liaoning Key Laboratory of Polymer Science and Engineering, Dalian 116024 (China); School of Chemical Engineering, Dalian University of Technology, Dalian 116024 (China); Zhang, Shouhai, E-mail: zhangshh@dlut.edu.cn [State Key Laboratory of Fine Chemical, Dalian 116024 (China); Liaoning High Performance Polymer Engineering Research Center, Dalian 116024 (China); Liaoning Key Laboratory of Polymer Science and Engineering, Dalian 116024 (China); School of Chemical Engineering, Dalian University of Technology, Dalian 116024 (China); Han, Runlin [School of Chemical Engineering, Dalian University of Technology, Dalian 116024 (China); Jian, Xigao, E-mail: jian4616@dl.cn [State Key Laboratory of Fine Chemical, Dalian 116024 (China); Liaoning High Performance Polymer Engineering Research Center, Dalian 116024 (China); Liaoning Key Laboratory of Polymer Science and Engineering, Dalian 116024 (China); School of Chemical Engineering, Dalian University of Technology, Dalian 116024 (China)

    2012-09-01

    Highlights: Black-Right-Pointing-Pointer Composite nanofiltration membranes based on PPENK UF membranes were prepared. Black-Right-Pointing-Pointer Preparation parameters of polyamide/PPENK nanofiltration membranes were studied. Black-Right-Pointing-Pointer Polyamide/PPENK nanofitration membrane shows excellent thermal resistance. - Abstract: Novel thermally stable composite nanofiltration (NF) membranes were prepared from piperazine (PIP) and trimesoyl chloride (TMC) on poly (phthalazione ether nitrile ketone) (PPENK) ultrafiltration (UF) membranes by interfacial polymerization. The effects of monomers concentration, reaction time and organic solvents on the performance of composite membranes were investigated. The effects of operating pressure and the salt solution concentration on the performance of composite membranes were also discussed. The different salts rejection of PPENK composite membranes decreased in the order of Na{sub 2}SO{sub 4} > MgSO{sub 4} > Al{sub 2}(SO{sub 4}){sub 3} > NaCl > MgCl{sub 2}, which indicated a negative charge at the membrane surface. The flux and Na{sub 2}SO{sub 4} rejection of PPENK composite membranes reached 57.9 L/m{sup 2} h and 98.4% under the optimized conditions and operating pressure of 1.0 MPa. Furthermore, the morphology and chemical structure of membranes were examined by scanning electronic microscopy (SEM) and Fourier transform infrared spectroscopy (FT-IR), respectively. Moreover, the thermal stability of PPENK NF membranes was also investigated. When temperature of the feed solution raised from 20 Degree-Sign C to 80 Degree-Sign C, the permeation flux increased about four times without significant change of rejection. The flux increased first then reached a plateau and the rejection kept constant when PPENK NF membranes in boiling de-ionized water were boiled to 3 h.

  7. Preparation of Pd-Diimine@SBA-15 and Its Catalytic Performance for the Suzuki Coupling Reaction

    Directory of Open Access Journals (Sweden)

    Jiahuan Yu

    2016-11-01

    Full Text Available A highly efficient and stable Pd-diimine@SBA-15 catalyst was successfully prepared by immobilizing Pd onto diimine-functionalized mesoporous silica SBA-15. With the help of diimine functional groups grafted onto the SBA-15, Pd could be anchored on a support with high dispersion. Pd-diimine@SBA-15 catalyst exhibited excellent catalytic performance for the Suzuki coupling reaction of electronically diverse aryl halides and phenylboronic acid under mild conditions with an ultralow amount of Pd (0.05 mol % Pd. When the catalyst amount was increased, it could catalyze the coupling reaction of chlorinated aromatics with phenylboronic acid. Compared with the catalytic performances of Pd/SBA-15 and Pd-diimine@SiO2 catalysts, the Pd-diimine@SBA-15 catalyst exhibited higher hydrothermal stability and could be repeatedly used four times without a significant decrease of its catalytic activity.

  8. Dye-sensitized solar cell and photocatalytic performance of nanocomposite photocatalyst prepared by electrochemical anodization

    Indian Academy of Sciences (India)

    MOHAMAD MOHSEN MOMENI

    2016-10-01

    This study compares different Fe-doped TiO$_2$ nanostructures in terms of their photocatalytic performance. Iron-doped TiO$_2$ nanostructures (FeTNs) were prepared by in situ anodizing of titanium in a single-stepprocess in the presence of 3, 9, 15 and 21 mM K$_3$Fe(CN)$_6$. Potassium ferricyanide was used as the iron source. Prepared films are amorphous, so these layers were thermally annealed. The effect of iron doping on the photoelectrochemical properties (including dye-sensitized solar cells) and photocatalysis properties (decomposition of methomyl) was investigated. In all investigated cases, the sample C, which was formed by anodizing in a ethylene glycol electrolyte containing 9 mM K$_3$Fe(CN)$_6$, exhibited better performance than the bare TiO$_2$ and FeNTs fabricated using other iron concentrations. This study demonstrated a feasible and simple anodizing method to fabricate an effective, reproducible and inexpensive photocatalyst for various applications.

  9. INVESTIGATION OF SOFTENING AGENT PREPARATION AND PERFORMANCE OF HANDMADE ECOCOMPOSITES WITH CONIFEROUS WOOD AND BASALT FIBERS

    Institute of Scientific and Technical Information of China (English)

    Guangjian Wang; Deku Shang; Kailiang Zhang; Linna Hu; Zhenhua Guo

    2004-01-01

    In this investigation, basalt mineral fiber softening agent was prepared in order to obtain desirable flexible performance. Stability and physical chemistry natures of softening agent were evaluated by particle size distribution, dilution, storage and folding endurance etc. Constitutes of basalt and wood fibers were determined by energy dispersion analysis X-ray which served as an accessory of scanning electron microscopy (SEM-EDAX). Naturally degradable ecocomposite was prepared by basalt and wood fibers. The results of SEM observation illustrated that the wood and basalt fibers were blended uniformly. The impact factors of beating degree, content of wood fibers and adhesive etc. were discussed. The structure of the naturally degradable ecocomposite was contrasted with that of pure wood fibers and the cause of excellent filtration performance was analyzed. Compared with traditional methods, it was of saving wood resource,a large amount of water and reducing second pollution. As a consequence, the ecocomposite harmonized with environment and accorded with requirement of benignly friendly environment.

  10. [Cell biology researches aboard the robotic space vehicles: preparation and performance].

    Science.gov (United States)

    Tairbekov, M G

    2006-01-01

    The article reviews the unique aspects of preparation and performance of cell biology experiments flown on robotic space vehicles Bion and Foton, and gives an overview of key findings in researches made under the author's leadership over the past decades. Described are the criteria of selecting test objects, and the conditions required for preparation and implementation of space and control (synchronous) experiments. The present-day status and issues of researches into cell responsivity to space microgravity and other factors are discussed. Also, potentialities of equipment designed to conduct experiments with cell cultures in vitro and populations of single-celled organisms are presented, as well as some ideas for new devices and systems. Unveiled are some circumstances inherent to the development and performance of space experiments, setting up laboratory facilities at the launch and landing site, and methods of safe transportation and storage of biosamples. In conclusion, the author puts forward his view on biospecies, equipment and areas of research aboard future space vehicles.

  11. Preparation and Electrocatalytic Performance of Bi-Modified Quartz Column Particle Electrode for Phenol Degradation

    Directory of Open Access Journals (Sweden)

    Jiguo Huang

    2015-01-01

    Full Text Available Bismuth oxide (Bi2O3 and its composites have good electrocatalytic performance. Quartz column is a good kind of catalyst carrier with the characteristics of high mechanical strength and good stability. A novel Bi-modified quartz column particle electrode (BQP was prepared by the dipping-calcination method. The characterization results revealed that Bi2O3 was successfully loaded on quartz column. The optimum preparation condition was calcining at 550°C for 4 h. Electrocatalytic performance was evaluated by the degradation of phenol and the results indicated that the triclinic phase of Bi2O3 showed the best electrocatalytic property. Besides, when the dosage concentration of the particle electrode was 125 g/L and the electrolytic voltage was 12 V, the degradation rate of phenol (200 mg/L reached the highest (94.25%, compared with 70.00% of that in two-dimensional (2D system. In addition, the removal rate of chemical oxygen demand (COD was 75.50%, compared with 53.30% of that in 2D system. The reusability and regeneration of BQP were investigated and the results were good. Mechanism of enhanced electrochemical oxidation by BQP was evaluated by the capture of hydroxyl radical.

  12. Solvent-Assisted Preparation of High-Performance Mesoporous CH₃NH₃Pbl₃ Perovskite Solar Cells.

    Science.gov (United States)

    Li, Zhi-Hua; Liu, Jie; Ma, Jing-Yuan; Jiang, Yan; Ge, Qian-Qing; Ding, Jie; Hu, Jin-Song; Wan, Li-Jun

    2016-01-01

    Organometal trihalide perovskite based solar cells have attracted great attention worldwide since their power conversion efficiency (PCE) have risen to over 15% within only 3 years of development. Comparing with other types of perovskite solar cells, mesostructured perovskite solar cells based on CH₃NH₃Pbl₃ as light harvesting material have already demonstrated remarkable advance in performance and reproducibility. Here, we reported a mesoscopic TiO₂/CH₃NH₃Pbl₃ heterojunction solar cell with uniform perovskite thin film prepared via solvent-assisted solution processing method. The best performing device delivered photocurrent density of 20.11 mA cm⁻², open-circuit voltage of 1.02 V, and fill factor of 0.70, leading to a PCE of 14.41%. A small anomalous hysteresis in the J-V curves was observed, where the PCE at forward scan was measured to be 84% of the PCE at reverse scan. Based on a statistical analysis, the perovskite solar cells prepared by the reported method exhibited reproducible and high PCE, indicating its promising application in the fabrication of low-cost and high-efficiency perovskite solar cells.

  13. Investigating the Relationship between Test Preparation and "TOEFL iBT"® Performance. Research Report. ETS RR-14-15

    Science.gov (United States)

    Liu, Ou Lydia

    2014-01-01

    This study investigates the relationship between test preparation and test performance on the "TOEFL iBT"® exam. Information on background variables and test preparation strategies was gathered from 14,593 respondents in China through an online survey. A Chinese standardized English test was used as a control for prior English ability.…

  14. Institutional Factors Affecting the Economic Performance of Peasant Special Cooperative Organization——A Case of Cuiping District,Yibin City,China

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Literatures about the institutional arrangement of the Peasant Special Cooperative Organization are summarized.Based on the introduction of theoretical background,the overall level of annual earnings in the year 2008 is selected as a dependent variable to evaluate the economic performance of cooperative organizations,according to the investigation on 54 Peasant Special Cooperative Organizations in Cuiping District,Sichuan Province,China.A total of 13 institutional indices passing the correlation test are chosen as independent variables.Relationship between the development level and the institutional factors affecting the economic performance of cooperative organizations is studied by using factor analysis method.Result shows that there is relatively high consistency between the score of institutional factor and the development level of cooperative organization.Both macroscopic support system and internal benefit distribution system have greater impacts on the Peasant Special Cooperative Organization;the internal supervision factor and the interest factor of core members have insignificant impacts on the economic performance;and the production management factor has little effect on economic performance.Based on this,several suggestions are put forward,including standardizing and reforming the system,improving the countermeasures for economic performance,strengthening the support and policy guidance for Peasant Special Cooperative Organization,improving and standardizing the distribution of benefit system,the security system and monitoring system for core members’ interests,and fully reflecting the interests of core members.

  15. Nanotubes within transition metal silicate hollow spheres: Facile preparation and superior lithium storage performances

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Fan; An, Yongling; Zhai, Wei; Gao, Xueping [Key Laboratory for Liquid–Solid Structural Evolution & Processing of Materials (Ministry of Education), Jinan 250100 (China); Feng, Jinkui, E-mail: jinkui@sdu.edu.cn [Key Laboratory for Liquid–Solid Structural Evolution & Processing of Materials (Ministry of Education), Jinan 250100 (China); Ci, Lijie [Key Laboratory for Liquid–Solid Structural Evolution & Processing of Materials (Ministry of Education), Jinan 250100 (China); Xiong, Shenglin [School of Materials Science and Engineering, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100 (China)

    2015-10-15

    Highlights: • The hollow Co{sub 2}SiO{sub 4}, MnSiO{sub 3} and CuSiO{sub 3} were successfully prepared by a facile hydrothermal method using SiO{sub 2} nanosphere. • The hollow Co{sub 2}SiO{sub 4}, MnSiO{sub 3} and CuSiO{sub 3} were tested as anode materials for lithium batteries. • The hollow Co{sub 2}SiO{sub 4}, MnSiO{sub 3} and CuSiO{sub 3} delivered superior electrochemical performance. • The lithium storage mechanism is probe via cyclic voltammetry and XPS. - Abstract: A series of transition metal silicate hollow spheres, including cobalt silicate (Co{sub 2}SiO{sub 4}), manganese silicate (MnSiO{sub 3}) and copper silicate (CuSiO{sub 3}.2H{sub 2}O, CuSiO{sub 3} as abbreviation in the text) were prepared via a simple and economic hydrothermal method by using silica spheres as chemical template. Time-dependent experiments confirmed that the resultants formed a novel type of hierarchical structure, hollow spheres assembled by numerous one-dimensional (1D) nanotubes building blocks. For the first time, the transition metal silicate hollow spheres were characterized as novel anode materials of Li-ion battery, which presented superior lithium storage capacities, cycle performance and rate performance. The 1D nanotubes assembly and hollow interior endow this kind of material facilitate fast lithium ion and electron transport and accommodate the big volume change during the conversion reactions. Our study shows that low-cost transition metal silicate with rationally designed nanostructures can be promising anode materials for high capacity lithium-ion battery.

  16. COMPARATIVE STUDY OF DISEASE PATTERNS AND SCHOLASTIC PERFORMANCE AMONG RURAL, URBAN AND TRIBAL GOVERNMENT RESIDENTIAL HOSTEL CHILDREN OF EAST GODAVARI DISTRICT

    Directory of Open Access Journals (Sweden)

    Sirigineedi Chandra

    2016-04-01

    Full Text Available BACKGROUND Most of the children from tribal, rural and urban slums are found to suffer from health problems due to poor quality of life. Malnutrition continues to be major threat leading to morbidities and poor scholastic performance in these children. The welfare hostels for the children are established for weaker sections of the society as an important social welfare measure in India since long time. The data regarding the nutritional, morbidity status and scholastic performance of the children in social welfare hostels are sparse. With this background, this study was conducted to evaluate the extent and pattern of health status of school age children and their scholastic performance using a predesigned proforma. METHODS The study was conducted in randomly selected 3 hostels from urban, rural and tribal areas of East Godavari District. It was a cross sectional observational study. RESULTS Mild anaemia, poor attention and calculation ability, dental caries, refractive errors, nonspecific headaches, dermatological problems, Vitamin A deficiency were the commonly seen problems in all rural, urban, tribal hostellers. CONCLUSION Anaemia, dermatological problems and dental caries are more commonly observed in all, hence hygienic conditions and nutritional supplementations are to be improved. Regular de-worming program has to be successfully implemented in the hostels to decrease the prevalence of worm infestations. Poor scholastic performance can be improved by implementing skilled training programs like Pradhan Mantri Kaushal Vikas Yojana (PMKVY in these hostels along with formal education.

  17. Preparation of UV curing crosslinked polyviologen film and its photochromic and electrochromic performances

    Science.gov (United States)

    Gao, Li-ping; Ding, Guo-jing; Wang, Yue-chuan; Yang, Yu-lin

    2011-11-01

    Polyether urethane diacrylate matrix (PEUDA) and acrylate-functional viologen (ACV2+) were successfully synthesized and characterized in detail by FTIR and 1H NMR spectra, respectively. Subsequently, they were used to prepare UV curing crosslinked polyviologen film in combination with 2-hydroxyethyl methacrylate (HEMA), trimethylolpropane ethoxylate triacrylate (TMPTA) and diphenyl (2, 4, 6-trimethylbenzoyl) phosphine oxide (TPO). UV curing approach confined the polyviologen film on ITO electrode, which imparted the film excellent adhesion ability to ITO glass, good solvent resistance, excellent chemical stability, excellent optical and electrochemical properties. The crosslinked PACV2+ film exhibited excellent photochromic and electrochromic performances. After UV illumination for 60 s, the crosslinked PACV2+ film can swiftly change its color from pale yellow to deep blue, while the optical transmission of crosslinked PACV2+ film at 610 nm did not change significantly and still retained about 63.6% after 30 cycles. Simultaneously, the cyclic voltammetry experiment showed the PACV2+ film can undergo repeatable electrochemical redox reactions with good reversibility beyond the 10th scan. Furthermore, the electrochromic device composed of the PACV2+ film and gel electrolyte film can undergo reversible color change in response to the external voltages of -2.0 V and 2.0 V, respectively, while the contrast of EC device at 610 nm did not change significantly and still retained about 39.5% after 10 cycles. This UV curing approach to preparing viologen-functional film offers a method to preparing large-scale photo- and electrochromic device, which is relatively simple, high productivity, energy saving, and environmental protection.

  18. Facile preparation of nitrogen-doped hierarchical porous carbon with high performance in supercapacitors

    Energy Technology Data Exchange (ETDEWEB)

    Yan, Kun [State Key Laboratory of Advanced Processing and Recycling of Non-ferrous Metals, Lanzhou University of Technology, Lanzhou 730050 (China); Kong, Ling-Bin, E-mail: konglb@lut.cn [State Key Laboratory of Advanced Processing and Recycling of Non-ferrous Metals, Lanzhou University of Technology, Lanzhou 730050 (China); School of Materials Science and Engineering, Lanzhou University of Technology, Lanzhou 730050 (China); Shen, Kui-Wen; Dai, Yan-Hua; Shi, Ming; Hu, Bing [State Key Laboratory of Advanced Processing and Recycling of Non-ferrous Metals, Lanzhou University of Technology, Lanzhou 730050 (China); Luo, Yong-Chun; Kang, Long [School of Materials Science and Engineering, Lanzhou University of Technology, Lanzhou 730050 (China)

    2016-02-28

    Graphical abstract: Preparing and activating process of nitrogen-doped hierarchical porous carbon (NHPC). - Highlights: • The well-defined PAN-b-PMMA copolymer was synthesized by atom transfer radical polymerization with narrow molecular weight distribution. • Nitrogen-doped hierarchical porous structure (NHPC) was prepared through a simple carbonization procedure of PAN-b-PMMA precursor. • NHPC possessed hierarchical porous structure with high BET surface area of 257 m{sup 2} g{sup −1} and DFT mesopore size of 14.61 nm. • Effects of activation conditions on supercapacitive behavior were systematically studied. - Abstract: The nitrogen-doped hierarchical porous carbon (NHPC) material was successfully prepared through a simple carbonization procedure of well-defined diblock copolymer precursor containing nitrogen-enriched carbon source, i.e., polyacrylonitrile (PAN), and asacrificial block, i.e., polymethylmethacrylate (PMMA). PAN-b-PMMA diblock copolymer was synthesized by atom transfer radical polymeriation (ATRP) with narrow molecular weight distribution. The as-obtained NHPC possessed nitrogen-doped hierarchical porous structure with high BET surface area of 257 m{sup 2} g{sup −1} and Nonlocal density functional theory (NLDFT) mesopore size of 14.61 nm. Surface activated nitrogen-doped hierarchical porous carbon (A-NHPC) materials were obtained by subsequent surface activation with HNO{sub 3} solution. The effects of activation conditions on supercapacitive behavior were systematically studied, a maximum specific capacitance of 314 F g{sup −1} at a current density of 0.5 A g{sup −1} was achieved in 2 M KOH aqueous electrolyte. Simultaneously, it exhibited excellent rate capability of 67.8% capacitance retention as the current density increased from 0.5 to 20 A g{sup −1} and superior cycling performance of 90% capacitance retention after 10,000 cycles at the current density of 2 A g{sup −1}.

  19. A facile method to prepare a high performance solid-state flexible paper-based supercapacitor

    Energy Technology Data Exchange (ETDEWEB)

    Shieh, Jen-Yu; Zhang, Sheng-Hui; Wu, Cheng-Hung [Institute of Electro-Optical and Materials Science, National Formosa University, 64 Wenhua Road, Huwei, Yunlin 63208, Taiwan (China); Yu, Hsin Her, E-mail: hhyu@nfu.edu.tw [Department of Biotechnology, National Formosa University, 64 Wenhua Road, Huwei, Yunlin 63208, Taiwan (China)

    2014-09-15

    Graphical abstract: A flexible paper-based supercapacitor was assembled into a sandwich structure, which exhibits well-retained triangular-shaped curves. The cycle life stability of this device still retains about 96% of the initial capacitance after 2000 cycles at a scan rate of 400 mV/s. An as-fabricated paper-based supercapacitor could light a red LED well after charging at constant potential of 3 V. - Highlights: • A facile approach is proposed to fabricate paper-based supercapacitors. • Apple pectin is an excellent dispersant for MWCNTs. • Paper provides a strong binding and flexible characteristic for electrode. • A paper-based supercapacitor could light a red LED after charging. • This device shows excellent electrochemical performance and cycling stability. - Abstract: We propose a low cost and simple method to prepare a paper-based supercapacitor in this study. Multi-walled carbon nanotubes (MWCNTs) were dispersed with a pectin solution under an ultrasonic homogenizer. Carbon nanotube suspension was prepared using a centrifuge to eliminate impurities. The dispersed MWCNTs suspension was dropped and dried onto the shallow surface of commercial copy paper. A paper-based conductive paper was formed as the electrodes. The electrical conductivity and dispersed morphology of the paper-based conductive paper were examined by four probes, atomic force microscope (AFM), scanning electron microscope (SEM) and transmission electron microscope (TEM). The solid-state electrolyte was prepared by casting a solution of phosphoric acid and polyvinyl alcohol onto a glass plate. The paper-based supercapacitor was constructed with one solid-state electrolyte inserted between two electrodes, which were assembled into a sandwich structure by hot press. The specific capacitance and cycle-life stability of the paper-based supercapacitor was investigated by cyclic voltammetry analysis.

  20. Physics or Mathematics Preparation - which is the better predictor of performance in a first, calculus-based college physics course?

    Science.gov (United States)

    Chase, Norma

    2011-11-01

    Data spanning fifteen semesters and including more than 1200 students showed far less than the anticipated difference in performance between students with quite diverse levels of physics preparation. Students ranged from those with no prior physics course work to those with two or more years of HS physics and prior courses in college physics. Less prior physics training frequently coincided with better performance in the first calculus-based course. Preparation in mathematics, on the other hand, appeared critically important; students at the extremes of the math preparation spectrum were concentrated at the corresponding extremes of the physics grade distribution.

  1. Preparation, Physicochemical Characterization and Performance Evaluation of Gold Nanoparticles in Radiotherapy

    Directory of Open Access Journals (Sweden)

    Ali Kamiar

    2013-08-01

    Full Text Available Purpose: The aim of the present study was preparation, physicochemical characterization and performance evaluation of gold nanoparticles (GNPs in radiotherapy. Another objective was the investigation of anti-bacterial efficacy of gold nanoparticle against E. coli clinical strains. Methods: Gold nanoparticles prepared by controlled reduction of an aqueous HAuCl4 solution using Tri sodium citrate. Particle size analysis and Transmission electron microscopy were used for physicochemical characterization. Polymer gel dosimetry was used for evaluation of the enhancement of absorbed dose. Diffusion method in agar media was used for investigation of anti-bacterial effect. Results: Gold nanoparticles synthesized in size range from 57 nm to 346 nm by planning different formulation. Gold nanoparticle in 57 nm size increased radiation dose effectiveness with the magnitude of about 21 %. At the concentration of 400 ppm, Nano gold exhibited significant anti-bacterial effect against E. coli clinical strains. Conclusion: It is concluded that gold nanoparticles can be applied as dose enhancer in radiotherapy. The Investigation of anti-bacterial efficacy showed that gold nanoparticle had significant effect against E. coli clinical strains.

  2. Preparation, Characterization and Performances of Powdered Polycarboxylate Superplasticizer with Bulk Polymerization

    Directory of Open Access Journals (Sweden)

    Xiao Liu

    2014-08-01

    Full Text Available A polycarboxylate superplasticizer (PCE was synthesized in a non-solvent system with bulk polymerization and then was pulverized into powdered form to achieve a rapid transportation and convenient preparation. PCE synthesized by using isopentenyl polyethylene glycol (TPEG or isobutenyl polyethylene glycol (IPEG as a macromonomer exhibited the best fluidities and retaining properties at 80 °C and 75 °C, respectively. Besides, azobisisobutyronitrile (AIBN was suitable as an initiator, and the fumaric acid was suitable as the third monomer. The test results of 1H nuclear magnetic resonance (1H NMR confirmed the occurrences of polymerization, and the measurement results of molecular weight and distribution showed that PCE molecular weight characteristics were in accordance with their fluidity properties in cement paste. The application performances in cement showed that PCEs with the best paste fluidity retentions had the longest final setting time and the shortest setting time interval, and the PCEs with good fluidity properties can obviously delay the hydration process and lower the hydration heat. Accordingly, this is a novel, energy-saving and economical method to prepare powdered PCE in the field of concrete admixtures.

  3. The Optimization of Matrix Preparation Process and Performance Testing for Molten Carbonate Fuel Cell

    Directory of Open Access Journals (Sweden)

    Jian Cheng

    2014-01-01

    Full Text Available A key component in the molten carbonate fuel cell (MCFC is electrolyte matrix, which provides both ionic conduction and gas sealing. The aim of this work is to investigate the effects of selected operating conditions on the performance of the matrix preparation. Slurries were prepared to produce matrices by the technique of tape casting. The characteristics of the slurries and matrices were examined by laser particle size analyzer, scanning electron microscopy, and BET surface area analyzer. The testing results revealed that a slurry composition with 40 wt.% lithium aluminate was the optimal formulation to produce a good matrix with a pore size distribution of 0.1–0.4 μm and porosity of 50 vol.%. Coarse and fine LiAlO2 particles were added in the matrix slurry to enhance the mechanical strength. Several green sheets were heated and pressed to enhance the bulk density to get a dense matrix of MCFC. Finally, a single MCFC was assembled and tested. The testing results showed the matrix with 40% solid loading gave the maximum discharge current of 20 A at 0.56 V.

  4. Simultaneous determination of 30 ginsenosides in Panax ginseng preparations using ultra performance liquid chromatography

    Science.gov (United States)

    Park, Hee-Won; In, Gyo; Han, Sung-Tai; Lee, Myoung-Woo; Kim, So-Young; Kim, Kyung-Tack; Cho, Byung-Goo; Han, Gyeong-Ho; Chang, Il-Moo

    2013-01-01

    A quick and simple method for simultaneous determination of the 30 ginsenosides (ginsenoside Ro, Rb1, Rb2, Rc, Rd, Re, Rf, Rg1, 20(S)-Rg2, 20(R)-Rg2, 20(S)-Rg3, 20(R)-Rg3, 20(S)-Rh1, 20(S)-Rh2, 20(R)-Rh2, F1, F2, F4, Ra1, Rg6, Rh4, Rk3, Rg5, Rk1, Rb3, Rk2, Rh3, compound Y, compound K, and notoginsenoside R1) in Panax ginseng preparations was developed and validated by an ultra performance liquid chromatography photo diode array detector. The separation of the 30 ginsenosides was efficiently undertaken on the Acquity BEH C-18 column with gradient elution with phosphoric acids. Especially the chromatogram of the ginsenoside Ro was dramatically enhanced by adding phosphoric acid. Under optimized conditions, the detection limits were 0.4 to 1.7 mg/L and the calibration curves of the peak areas for the 30 ginsenosides were linear over three orders of magnitude with a correlation coefficients greater than 0.999. The accuracy of the method was tested by a recovery measurement of the spiked samples which yielded good results of 89% to 118%. From these overall results, the proposed method may be helpful in the development and quality of P. ginseng preparations because of its wide range of applications due to the simultaneous analysis of many kinds of ginsenosides. PMID:24235860

  5. Preparation of nitrogen and sulfur co-doped ordered mesoporous carbon for enhanced microwave absorption performance

    Science.gov (United States)

    Yuan, Xiaoyan; Xue, Xingkun; Ma, Hailong; Guo, Shouwu; Cheng, Laifei

    2017-09-01

    Ordered mesoporous carbon nanomaterials (OMCs) co-doped with homogeneous nitrogen and sulfur heteroatoms were prepared by nanocasting with the pyrrole oligomer catalyzed by sulfuric acid as a precursor and ordered mesoporous silica SBA-15 as a hard-template. By multi-technique approach utilization, it was demonstrated that the N and S co-doped OMCs possessed high ordered mesoporous structures, large surface areas and homogeneous distribution of heteroatoms. As a microwave absorber, the as-prepared materials exhibited a minimum reflection loss (RL) of -32.5 dB at the thickness of 2.5 mm and an absorption bandwidth of 3.2 GHz (RL < -10 dB) in X-band (8.2-12.4 GHz). The good microwave absorption performance was mainly originated from the high electrical conductivity induced by the high surface activity and special structures. And microwave energy can be effectively attenuated through multiple reflections and absorptions in complex conductive network. The design strategy in this work would contribute to the production of a lightweight absorber, presenting a strong absorbency and a wide bandwidth in microwave frequency.

  6. Preparation of manganese dioxide loaded activated carbon adsorbents and their desulfurization performance

    Science.gov (United States)

    Zhang, Jiaojing; Wang, Guojian; Wang, Wenyi; Song, Hua; Wang, Lu

    2016-12-01

    Manganese dioxide loaded activated carbon adsorbents (MnO2/AC) were prepared and characterized by N2 adsorption-desorption, BET method, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectrometry (FT-IR) and scanning electron microscopy (SEM). Effects of preparation conditions and adsorption conditions on desulfurization performance of the adsorbents were studied in a fixed-bed adsorption apparatus. Experimental results show that the surface area and pore volume of MnO2/AC decreased compared with the unmodified activated carbon, but the adsorption capacity to H2S was improved greatly. A suitable H2S removal activity was obtained with manganese dioxide to activated carbon ratio of 1.1: 1 and the calcination temperature of 250°C. At the adsorption temperature of 40°C and gas flow rate of 20 mL/min, the H2S saturation capacity and H2S removal rate reached up to 713.25 mg/g and 89.9%, respectively.

  7. Preparation and chromatographic performance of polymer-based anion exchangers for ion chromatography: A review.

    Science.gov (United States)

    Zatirakha, A V; Smolenkov, A D; Shpigun, O A

    2016-01-21

    In the last decade the developments in the field of ion chromatography (IC) were aimed at increasing the efficiency, sensitivity and rapidity of analysis, as well as on improving separation selectivity. Since selectivity and efficiency to the large extent depend on the surface chemistry of the stationary phase, the development of novel anion exchangers remains one of the priority tasks in modern IC. The exact chemistry of commercially available resins is not known and not many literature data devoted to the procedures of preparing anion exchangers for IC have become available in the last 10-15 years. However, the knowledge about the surface chemistry of anion exchangers can provide understanding of the trends in selectivity and efficiency changes, as well as help with the choice of the stationary phase type suitable for solving a particular analytical task. The current review is devoted to the methods of preparing anion exchangers based on polystyrene-divinylbenzene (PS-DVB) and ethylvinylbenzene-divinylbenzene (EVB-DVB) for IC of inorganic and small organic anions and is aimed at demonstrating the improvement of their performance over the years, which was brought by the development of the new types of stationary phase architecture.

  8. A Study on Theoretical Model and Applied Evaluation of Land Use Performance of High-tech Zone in Urban Fringe: A Case Study in Haidian District, Beijing

    Institute of Scientific and Technical Information of China (English)

    Ban Maosheng; Fang Chuanglin; Liu Xiaoli

    2008-01-01

    High-tech industrial zone is an important carrier for constructing innovative cities.It also plays an important role in implementing the national independent innovative strategy.However,most of the high-tech industrial zones have many problems in their development process,such as efficiency of land use,weakness of oriented function and lack of land intensive.To solve these problems,the authors of this paper introduced the concept of land use performance and established the theoretical model to assess the land use performance of high-tech industrial zones.The model consists of the following three-dimensional parts:land use benefit,land use efficiency and innovative function.Based on this theory model,an index system which was composed of three secondary indictors,eight tertiary indictors and 37 fottrth-grade indictors was set up to evaluate the land use performance of high-teeh zone.To avoid the defects of plus model and function model,the authors brought out a three-dimensional evaluation model to examine the index of the land use performance of the high-tech industrial parks,which equals to the evaluation indicator system of land use performance of high-tech zone based on the above research.The authors examined the land use performance of five different high-tech industrial parks in Haidian District,Beijing City.The results indicated that the indicator system performs better in the aspect of evaluating land use benefit,land use efficiency and function of the high-teeh industrial zone compared with other models.

  9. Magnetic Field-Assisted Perovskite Film Preparation for Enhanced Performance of Solar Cells.

    Science.gov (United States)

    Wang, Haoxu; Lei, Jie; Gao, Fei; Yang, Zhou; Yang, Dong; Jiang, Jiexuan; Li, Juan; Hu, Xihong; Ren, Xiaodong; Liu, Bin; Liu, Jing; Lei, Hairui; Liu, Zhike; Liu, Shengzhong Frank

    2017-07-05

    Perovskite solar cells (PSCs) are promising low-cost photovoltaic technologies with high power conversion efficiency (PCE). The crystalline quality of perovskite materials is crucial to the photovoltaic performance of the PSCs. Herein, a simple approach is introduced to prepare high-quality CH3NH3PbI3 perovskite films with larger crystalline grains and longer carriers lifetime by using magnetic field to control the nucleation and crystal growth. The fabricated planar CH3NH3PbI3 solar cells have an average PCE of 17.84% and the highest PCE of 18.56% using an optimized magnetic field at 80 mT. In contrast, the PSCs fabricated without the magnetic field give an average PCE of 15.52% and the highest PCE of 16.72%. The magnetic field action produces an ordered arrangement of the perovskite ions, improving the crystallinity of the perovskite films and resulting in a higher PCE.

  10. Preparation and Cracking Performance of FCC Co-Catalyst for Enhancing Light Oil Production

    Institute of Scientific and Technical Information of China (English)

    Wu Feiyue; Shi Li; Weng Huixin; Wang Xin

    2008-01-01

    In this paper,a FCC co-catalyst for enhancing the light oil production was prepared by the sol-gel method,and its effect on the performance of residue cracking catalysts was evaluated in a CCFFB reactor.The test results indicated that the liquid product yield increased obviously,after the surface of FCC equilibrium catalyst was impregnated with the co-catalyst.The yields of dry gas,slurry and coke decreased,while the diesel yield changed slightly.And the crackability of residue was increased; the rate of coke deposition on catalyst surface was decreased,with the thermal cracking reactions inhibited.All these results showed that the co-catalyst could improve the density of acid sites and change the catalyst acidity,which could promote to prolong the catalyst activity by depositing the co-catalyst on the surface of FCC equilibrium catalysts.

  11. Preparation, characterisation, engine performance and emission characteristics of coconut oil based hybrid fuels

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Pranil J.; Singh, Anirudh [Division of Physics, School of Engineering and Physics, Faculty of Science, Technology and Environment, University of the South Pacific, 325 Fletcher Road, Suva (Fiji); Khurma, Jagjit [Division of Chemistry, School of Biological, Chemical and Environmental Sciences, Faculty of Science, Technology and Environment, University of the South Pacific, Suva (Fiji)

    2010-09-15

    In this study, hybrid fuels consisting of coconut oil, aqueous ethanol and a surfactant (butan-1-ol) were prepared and tested as a fuel in a direct injection diesel engine. After determining fuel properties such as the density, viscosity and gross calorific values of these fuels, they were used to run a diesel engine. The engine performance and exhaust emissions were investigated and compared with that of diesel. The experimental results show that the efficiency of the hybrid fuels is comparable to that of diesel. As the viscosity of the hybrid fuels decreased and approached that of diesel, the efficiency increased progressively towards that of diesel. The exhaust emissions were lower than those for diesel, except carbon monoxide emissions, which increased. Hence, it is concluded that these hybrid fuels can be used successfully as an alternative fuel in diesel engines without any modifications. Their completely renewable nature ensures that they are environmentally friendly with regard to their emissions characteristics. (author)

  12. Preparation and performance of CeO2 hollow spheres and nanoparticles

    Institute of Scientific and Technical Information of China (English)

    ZHANG Wenwen; CHEN Donghui

    2016-01-01

    CeO2 hollow spheres were synthesized by polystryrene sphere (PS) templates and CeO2 nanoparticles were prepared by a facile method. The as-obtained products were characterized by scanning electron microscopy (SEM), N2 adsorption-desorption, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and UV-vis diffuse reflectance spectra. The results showed that the structure of the obtained CeO2 hollow spheres was hollow microsphere with a diameter of 380 nm and the average particle size of CeO2 nanoparticles was about 1700 nm. The two samples' Brunauer-Emmett-Teller (BET) surface area was 67.1 and 37.2 m2/g. The CeO2 hollow spheres had a better performance than nanoparticles at UV-shielding because of higher surface area and the structure of hollow sphere.

  13. Preparation of lignosulfonate-acrylamide-chitosan ternary graft copolymer and its flocculation performance.

    Science.gov (United States)

    He, Kunpeng; Lou, Tao; Wang, Xuejun; Zhao, Wenhua

    2015-11-01

    As flocculant plays an important role in wastewater treatment, searching for high efficient and cost-effective flocculants has always become the challenge in chemical industry. In the current work, lignosulfonate-acrylamide-chitosan ternary copolymer was designed and prepared as a new kind of flocculant. The elemental analysis and structure characterization of FTIR and XRD showed that acrylamide successfully grafted onto the two natural polymers and amorphous macromolecules were formed. The natural polymers-based flocculant was water soluble and pH independent. As it had multiple functional groups from the raw materials, the amphoteric flocculant showed high color removal efficiency to anionic (acid blue 113, >95%), neutral (reactive black 5, >95%) and cationic dyes (methyl orange, >50%) in a wide range of flocculant dosage and pH windows. The ternary flocculant, based on lignosulfonate, chitosan, and acrylamide, might be a promising material in practical applications from the perspective of cost, source and performance.

  14. Preparation and Performance of Bipolar Membranes with Liquid Ion-Exchange Medium

    Institute of Scientific and Technical Information of China (English)

    苏静; 余立新; 郝继华

    2003-01-01

    The current density is rather low in solid bipolar membranes, because the water transfer rate is relatively slow across solid bipolar membranes made of solid ion-exchange materials. This paper describes the use of polymer solutions, such as phosphatic poly(vinyl alcohol) solution, poly(acrylic acid) solution and poly(vinyl alcohol) solutions with dispersed cation/anion-exchange resin particles to prepare bipolar membranes. The 0.1 mol/L NaOH and the 0.05 mol/L H2SO4 were used to test the performance of the bipolar membranes. For a fixed liquid layer thickness, both the current density and the selectivity increase with the concentration increase of a polyelectrolyte solution. The maximum current density measured in the experiment was 1497 A/m2 with a selectivity of 96.8%.

  15. Thermally Sprayed Large Tubular Solid Oxide Fuel Cells and Its Stack: Geometry Optimization, Preparation, and Performance

    Science.gov (United States)

    Zhang, Shan-Lin; Li, Cheng-Xin; Liu, Shuai; Li, Chang-Jiu; Yang, Guan-Jun; He, Peng-Jiang; Yun, Liang-Liang; Song, Bo; Xie, Ying-Xin

    2017-02-01

    In this study, we develop a large tubular solid oxide fuel cells design with several cells in series on a porous cermet support, which has many characteristics such as self-sealing, low Ohmic loss, high strength, and good thermal expansion coefficient matching. Here, we investigate aspects of the cell design, manufacture, performance, and application. Firstly, the cell length and number of cells in series are optimized by theoretical analysis. Then, thermal spraying is applied as a cost-effective method to prepare all the cell components. Finally, the performance of different types of cells and two types of stacks is characterized. The maximum output power of one tube, which had 20 cells in series, reaches 31 and 40.5 W at 800 and 900 °C, respectively. Moreover, the output power of a stack assembled with 56 tubes, each with ten cells in series, reaches 800 W at 830 °C. The excellent single tube and cell stack performance suggest that thermally sprayed tubular SOFCs have significant potential for commercialized application.

  16. Enhanced performance of lipase via microcapsulation and its application in biodiesel preparation

    Science.gov (United States)

    Su, Feng; Li, Guanlin; Fan, Yanli; Yan, Yunjun

    2016-01-01

    In the present study, a surface-active enzyme, lipase was immobilized in polyethyleneimine (PEI) microcapsules and then modified with oxidized multiwall carbon nanotubes (MWCNTs). The resulting lipase microcapsules exhibited higher activity and stability, since the activity of microcapsules was 21.9 folds than that of the free counterpart. Numerous interfaces which were created in polycondensation enhanced the performance of lipases. Illustrated by confocal laser scanning microscope (CLSM), it was found that microcapsules, whose barrier properties against molecules with diameter >4.6 nm, were with a semipermeable and porous membrane structure. The lipases preferred to locate in the wall of the microcapsules. The oxidized multiwall carbon nanotubes (MWCNTs) were further added to modify microcapsules, resulting in even higher activity. The nanocomposites were examined by scanning electron microscope (SEM) and zeta-potential analyzer. The results indicated the superior catalytic performances were attributed to the augmented interface and decreased positive charge. Finally, the MWCNTs modified microcapsules were utilized in producing biodiesel with a 97.15% yield and retained nearly 90% yield after running 10 cycles. This approach of microcapsulation will be highly beneficial for preparing various bio-active microcapsules with excellent catalytic performance. PMID:27424490

  17. Preparation of Ag/TiO2-zeolite adsorbents, their desulfurization performance, and benzothiophene adsorption isotherms

    Science.gov (United States)

    Song, Hua; Yang, Gang; Song, Hua-Lin; Wang, Deng; Wang, Xue-Qin

    2017-02-01

    A series of Ag/TiO2-NaY (TY) composite adsorbents were successfully prepared and characterized by X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, BET, scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS) techniques. The effects of TiO2 and Ag contents on the structure and desulfurization performance of NaY zeolite were studied. The results show that anatase phase is the main form of TiO2 in AgTY adsorbent, and the Y-zeolite framework remained unchanged. AgTY with 6 wt % of Ag and 50 wt % of TiO2 exhibited the best desulfurization performance with the effluent volume of 63.2 mL/g at 10 mg/L sulfur breakthrough level (desulfurization rate of 95%). The benzothiophene (BT) removal performance of the various adsorbents follows the order: NaY < TiO2 < TY-50 < AgTY-50-6. The equilibrium data were modeled by Langmuir and Freundlich equations. The Langmuir model can describe well the adsorption isotherms of BT over AgTY.

  18. One-pot preparation of a novel monolith for high performance liquid chromatography applications.

    Science.gov (United States)

    Jiao, Xiaoyan; Shen, Shigang; Shi, Tiesheng

    2015-12-15

    Various novel porous organic-based monoliths with the mode of hydrophobicity were synthesized by in situ free-radical crosslinking copolymerization and optimized for the separations of small molecules and high-performance reversed-phase chromatography (RP-chromatography). These monoliths contained co-polymers based on glycidyl methacrylate (GMA)/ethylene glycol dimethacrylate (EDMA)/tripropylene glycol diacrylate (TPGDA) or EDMA/TPGDA. A mixture of cetanol, methanol and poly (ethylene glycol) (PEG) was used as the porogen, with the ratio of these solvents being varied along with the polymerization temperature to generate a library of monoliths. The conditions were optimized and the resulting poly (GMA-co-TPGDA-co-EDMA) monolith was investigated by infrared spectrometer (IR), field emission scanning electron microscope (FESEM), and mercury intrusion porosimetry (MIP), respectively. The column performance was assessed by the separation of a series of neutral solutes of benzene derivatives. The result demonstrated that the prepared monolith exhibited an RP-chromatographic behavior and relatively homogeneous structure, good permeability and separation performance. Moreover, the relative standard deviations (RSDs) of the retention factor values for benzene derivatives were less than 1.5% (n=7, column-to-column). The approach used in this study was extended to the separation of anilines.

  19. Thermally Sprayed Large Tubular Solid Oxide Fuel Cells and Its Stack: Geometry Optimization, Preparation, and Performance

    Science.gov (United States)

    Zhang, Shan-Lin; Li, Cheng-Xin; Liu, Shuai; Li, Chang-Jiu; Yang, Guan-Jun; He, Peng-Jiang; Yun, Liang-Liang; Song, Bo; Xie, Ying-Xin

    2017-01-01

    In this study, we develop a large tubular solid oxide fuel cells design with several cells in series on a porous cermet support, which has many characteristics such as self-sealing, low Ohmic loss, high strength, and good thermal expansion coefficient matching. Here, we investigate aspects of the cell design, manufacture, performance, and application. Firstly, the cell length and number of cells in series are optimized by theoretical analysis. Then, thermal spraying is applied as a cost-effective method to prepare all the cell components. Finally, the performance of different types of cells and two types of stacks is characterized. The maximum output power of one tube, which had 20 cells in series, reaches 31 and 40.5 W at 800 and 900 °C, respectively. Moreover, the output power of a stack assembled with 56 tubes, each with ten cells in series, reaches 800 W at 830 °C. The excellent single tube and cell stack performance suggest that thermally sprayed tubular SOFCs have significant potential for commercialized application.

  20. Effects of preparation time and trial type probability on performance of anti- and pro-saccades.

    Science.gov (United States)

    Pierce, Jordan E; McDowell, Jennifer E

    2016-02-01

    Cognitive control optimizes responses to relevant task conditions by balancing bottom-up stimulus processing with top-down goal pursuit. It can be investigated using the ocular motor system by contrasting basic prosaccades (look toward a stimulus) with complex antisaccades (look away from a stimulus). Furthermore, the amount of time allotted between trials, the need to switch task sets, and the time allowed to prepare for an upcoming saccade all impact performance. In this study the relative probabilities of anti- and pro-saccades were manipulated across five blocks of interleaved trials, while the inter-trial interval and trial type cue duration were varied across subjects. Results indicated that inter-trial interval had no significant effect on error rates or reaction times (RTs), while a shorter trial type cue led to more antisaccade errors and faster overall RTs. Responses following a shorter cue duration also showed a stronger effect of trial type probability, with more antisaccade errors in blocks with a low antisaccade probability and slower RTs for each saccade task when its trial type was unlikely. A longer cue duration yielded fewer errors and slower RTs, with a larger switch cost for errors compared to a short cue duration. Findings demonstrated that when the trial type cue duration was shorter, visual motor responsiveness was faster and subjects relied upon the implicit trial probability context to improve performance. When the cue duration was longer, increased fixation-related activity may have delayed saccade motor preparation and slowed responses, guiding subjects to respond in a controlled manner regardless of trial type probability.

  1. Preparative separation of polyphenols from water-soluble fraction of Chinese propolis using macroporous absorptive resin coupled with preparative high performance liquid chromatography.

    Science.gov (United States)

    Li, Aifeng; Xuan, Hongzhuan; Sun, Ailing; Liu, Renmin; Cui, Jichun

    2016-02-15

    In this study, a preparative separation method was developed for isolation of eleven polyphenols from water-soluble fraction of Chinese propolis using macroporous absorptive resin (MAR) coupled with preparative high performance liquid chromatography (PHPLC). Water-soluble fraction of Chinese propolis was first "prefractioned" using MAR, which yielded four subfractions. The four subfractions were then isolated by PHPLC with an isocratic elution of methanol-water. Finally, eleven polyphenols were purified from Chinese propolis including caffeic acid, ferulic acid, isoferulic acid, 3,4-dimethoxy cinnamic acid, pinobanksin, caffeic acid benzyl ester, caffeic acid phenethyl ester, apigenin, pinocembrin, chrysin and galangin. The purities of the compounds were determined by HPLC and the chemical structures were confirmed by UV and NMR analysis. The method developed was simple, effective, rapid, scalable and economical, and it was a promising basis for large-scale preparation of multiple components from natural products.

  2. Preparation of graphene/vanadium oxide nanocomposite monolith and its electrochemical performance

    Energy Technology Data Exchange (ETDEWEB)

    Deng, Lingjuan; Ma, Zhanying; Li, Xiaobo; Fan, Guang, E-mail: Chemfang@163.com

    2015-10-15

    Graphical Abstract: Graphene/V{sub 2}O{sub 5}(G/V{sub 2}O{sub 5}) nanocomposite monolith is prepared in a mixture of ammonium vanadate, acetic acid and graphite oxide by one-step hydrothermal technology. Owing to the novel structure of ultralong V{sub 2}O{sub 5} nanobelts interpenetrated between the G nanosheets, the G/V{sub 2}O{sub 5} nanocomposite electrode shows higher specific capacitances and better cycle stability than those of G and V{sub 2}O{sub 5} electrodes for supercapaciors and lithium ion battaries. - Highlights: • G/V{sub 2}O{sub 5} nanocomposite monolith is prepared by one-step hydrothermal technology. • G/V{sub 2}O{sub 5} nanocomposite electrode shows much excellent capacitive property. • G/V{sub 2}O{sub 5} nanocomposite exhibits more stable cycle performance. - Abstract: Graphene/vanadium oxide nanocomposite (G/V{sub 2}O{sub 5}) monolith is prepared via a simple hydrothermal process. Owing to the intimate contact between the V{sub 2}O{sub 5} nanobelts and graphene nanosheets in the monolith, the nanocomposite shows excellent electric conductivity, and therefore makes the electrode–electrolyte contact better and Li{sup +} diffusion faster. A high specific capacitance of 163 F g{sup −1} has been achieved for G/V{sub 2}O{sub 5} electrode in 0.5 mol L{sup −1} K{sub 2}SO{sub 4} solution. The G/V{sub 2}O{sub 5} nanocomposite exhibits excellent cyclic performance with nearly 80% capacity retention at a current density of 5 A g{sup −1} in a testing range of 1000 cycles. Moreover, G/V{sub 2}O{sub 5} nanocomposite exhibits excellent discharge properties and cycle stability as an anode material for lithium ion batteries. The initial capacity is 1100 mAh g{sup −1} and the reversible capacity of 530 mAh g{sup −1} is maintained after 100 cycles at a current density of 50 mA g{sup −1}.

  3. Performance of health product risk management and surveillance conducted by health personnel at sub-district health promotion hospitals in the northeast region of Thailand

    Directory of Open Access Journals (Sweden)

    Kanjanarach T

    2014-10-01

    Full Text Available Tipaporn Kanjanarach,1,2 Raksaworn Jaisa-ard,1,2 Nantawan Poonaovarat3 1Faculty of Pharmaceutical Sciences, Khon Kaen University, Khon Kaen, Thailand; 2Center for Research and Development of Herbal Health Products, Khon Kaen University, Khon Kaen, Thailand; 3Health Consumer Protection, Chaiyapum Health Provincial Office, Chaiyapum, Thailand Background: Health personnel at sub-district health promotion hospitals (SD-HPHs are assigned to take responsibility for 15 activities related to health product risk management and surveillance (HP-RM&S. This cross-sectional survey aimed to identify factors that determined their job performance and to record their expressed needs to support HP-RM&S operation. In this study, job performance was defined as completion of all 15 activities. Methods: Self-administered postal questionnaires were used to collect data from 380 randomly selected health personnel who were in charge of HP-RM&S at SD-HPHs in the northeast of Thailand. Results: Thirty-six point one percent (n=137 of the respondents were able to perform all 15 of the HP-RM&S activities assigned to SD-HPHs. A logistic regression model identified three factors that statistically significantly determined the completion of all 15 HP-RM&S activities. These were: receiving a high or very high level of support from the community (adjusted odds ratio [OR]: 2.5; 95% confidence interval [CI]: 1.5, 4.1, the responsible persons for HP-RM&S did not hold an administrative position (adjusted OR: 1.7; 95% CI: 1.1, 2.7, and having at least one training session related to HP-RM&S per year (adjusted OR: 1.7; 95% CI 1.1, 2.6. There were 1,536 expressed needs which can be classified into four major categories, ie, training needs (41.6%, n=639, resource support (28.3%, n=435, mechanisms that facilitate HP-RM&S operation (24.1%, n=370 and adjusting of the scope of HP-RM&S (6.0%, n=92. The topics most frequently referred to in training needs were drug law, food law, and cosmetics

  4. Hightower Engineering Academy Prepares High School Students for the Engineering Professions - A Program by the Fort Bend Independent School District - II

    Science.gov (United States)

    Cain, Lee; Verret, Doug; Griffin, Richard

    1998-10-01

    Hightower Engineering Academy, a project of the Fort Bend Independent School District, near Houston Texas, introduces high school students to the engineering professions. It has a college preparatory curriculum in which students are first grounded in the fundamentals of science and mathematics. Then more specific courses help them develop an appreciation for, and many of the skills of, the engineering profession. The Academy will implement a consistent teaching philosophy using a diverse array of innovative technology. The Academy is unique in the degree of partnership with local industry and state universities. It is committed to using the best known science pedagogy in combination with proven teaching art, experienced science educators and state-of-the art facilities all aimed at providing future engineers with complete mastery of the foundation knowledge of the profession. Hightower is committed to a "constructivist" teaching philosophy, the synergy of teamwork, and an appreciation of personal and professional ethics To the greatest extent possible, Hightower will have working engineers present the profession to students. There will be guest lecturers, field trips, and mentorships. Students will participate in engineering-specific organizations and competitions. Students will build a portfolio of their accomplishments at Hightower. They will experience project-based learning, culminating in a senior project that will encompass college-level research, experimentation, data analysis, and technical writing.

  5. CST Performance of English Language Learners in Two Neighboring Districts from 2002-03 to 2012-13

    Science.gov (United States)

    Rios, Olga Lidia

    2015-01-01

    California has the largest share of the English Language Learner (ELL) student population in the U.S., and it continues to grow. English Language Learners are the fastest growing group in the public school population and they are underachieving. The purpose of this study was to evaluate the longitudinal changes in the performance of English…

  6. The Four-Day School Calendar: A Comparative Study of Student Performance Indicators in a Colorado School District

    Science.gov (United States)

    Reeves, Cheryl L.

    2014-01-01

    Because there was a gap in the literature about the nuances of a four-day school week, it was not known if there was a difference in performance indicators in a school calendar with Monday off compared to a school calendar with Friday off. The purpose of this comparative descriptive study was to determine if there was a difference in achievement…

  7. Assessment of the Temperament, Motivation, and Capability of a School System District for Emergency Management/Crisis Performance

    Science.gov (United States)

    Hoff, Larry A.

    2009-01-01

    This study was a cross-sectional study of leadership and staff of a public school system in Georgia concerning their temperament type, emergency management motivation and emergency management knowledge in relation to Emergency Management/Crisis performance (ERCM). The study consisted of an inclusive questionnaire that contains questions on four…

  8. Preparation and Characterization of a New Quercetin-bonded Stationary Phase for High Performance Liquid Chromatography

    Institute of Scientific and Technical Information of China (English)

    李来生; 方奕珊; 陈红; 张杨

    2012-01-01

    A quercetin-bonded silica gel stationary phase (QUSP) containing natural flavonoid ligand was first prepared via γ-glycidoxypropyltrimethoxysilane (KH-560) as a coupling reagent for high-performance liquid chromatography. Its chemical structure was characterized by Fourier infrared spectroscopy, elemental analysis, thermal thermogravimetry and 13C cross polarization/magic angle spinning nuclear magnetic resonance (CP/MAS NMR). The chromatographic property of QUSP was systematically evaluated by using neutral, basic and acidic aromatic com- pounds as probes. In order to clarify its retention mechanism, a comparative study of QUSP with conventional oc- tadecylsilyl-bonded stationary phase (ODS) was also carried out under the same conditions. The results showed that the new quercetin-bonded phase exhibited an excellent reversed-phase chromatographic property with relatively weak hydrophobicity. However, it has an advantage over ODS in the fast separation of polar aromatic compounds because the quercetin ligand could provide various sites besides hydrophobicity, such as hydrogen bonding, dipole-dipole, n-n staking and charge transfer interactions. QUSP was performed in the baseline separations of ion- ized polar basic or acidic compounds, including pyridines, anilines, pyrimidines, purines and phenols with symmet- ric peak shape in common mobile phases without buffer salt within relatively short time. The natural ligands from herbs are readily available and contain a variety of active sites, which facilitate the exploration of industrial chromatographic separation materials for green products.

  9. Preparation and performance study of a novel liquid scintillator with mixed solvent as the matrix

    Science.gov (United States)

    Zheng, Zhanlong; Zhu, Jiayi; Luo, Xuan; Xu, Yewei; Zhang, Qianfeng; Zhang, Xing; Bi, Yutie; Zhang, Lin

    2017-04-01

    A novel liquid scintillator with the mixed solvent as the matrix was prepared for obtaining a good comprehensive performance. In this ternary liquid scintillator, the combination of 20% pseudocumene (PC) and 80% linear-alkyl benzene (LAB) by volume was chosen as the mixed solvent, and 2,5-diphenyloxazole (PPO) and 1,4-bis(2-Methylstyryl) benzene (bis-MSB) were as the primary fluor and wavelength shifter, respectively. The optimum prescription was obtained with regard to the light yield. Some characterizations based on the optimal formulation were conducted. The fluorescence emission spectra and wavelength-dependent optical attenuation length of the sample were measured by the fluorescence spectrophotometer and an UV-Vis spectrometer, respectively. The light yield was characterized by adopting the home-made optical platform device. The decay time was tested by adopting the time-correlated single photon counting (TCSPC) technique featured in high dynamic range of several orders of magnitude in light intensity. The experimental test results showed that the sample had a fairly good comprehensive performance.

  10. Nanocellulose Derivative/Silica Hybrid Core-Shell Chiral Stationary Phase: Preparation and Enantioseparation Performance

    Directory of Open Access Journals (Sweden)

    Xiaoli Zhang

    2016-05-01

    Full Text Available Core-shell silica microspheres with a nanocellulose derivative in the hybrid shell were successfully prepared as a chiral stationary phase by a layer-by-layer self-assembly method. The hybrid shell assembled on the silica core was formed using a surfactant as template by the copolymerization reaction of tetraethyl orthosilicate and the nanocellulose derivative bearing triethoxysilyl and 3,5-dimethylphenyl groups. The resulting nanocellulose hybrid core-shell chiral packing materials (CPMs were characterized and packed into columns, and their enantioseparation performance was evaluated by high performance liquid chromatography. The results showed that CPMs exhibited uniform surface morphology and core-shell structures. Various types of chiral compounds were efficiently separated under normal and reversed phase mode. Moreover, chloroform and tetrahydrofuran as mobile phase additives could obviously improve the resolution during the chiral separation processes. CPMs still have good chiral separation property when eluted with solvent systems with a high content of tetrahydrofuran and chloroform, which proved the high solvent resistance of this new material.

  11. Preparation and Performance of Inorganic Heat Insulation Panel Based on Sepiolite Nanofibers

    Directory of Open Access Journals (Sweden)

    Fei Wang

    2014-01-01

    Full Text Available High efficiency and low cost thermal insulation energy saving panel materials containing sepiolite nanofibers were developed by means of the synergistic action of inorganic adhesive, curing agent, and hydrogen peroxide. The water soluble sodium silicate was used as inorganic adhesive, and the sodium fluorosilicate was chosen as curing agent. Moreover, appropriate amount of hydrogen peroxide was added in order to decrease the bulk density and improve the heat insulation performance of panel materials. The results showed that the synergistic action of inorganic adhesive, curing agent, and hydrogen peroxide could make thermal insulation energy saving panel materials have low bulk density and high mechanical performance, and the optimal process was as follows: 120°C of drying temperature, 1.6% of sodium silicate as inorganic adhesive, 12% of sodium fluorosilicate as curing agent in sodium silicate, and 2.5% of hydrogen peroxide. The thermal insulation energy saving panel materials as prepared could arrest heat transmission and resist external force effectively.

  12. Preparation and recognition performance of cytisine alkaloid-imprinted material prepared using novel surface molecular imprinting technique.

    Science.gov (United States)

    Gao, Baojiao; Niu, Qinyuan; Du, Ruikui

    2010-05-01

    Methacrylic acid was first graft-polymerized on the surfaces of micron-sized silica gel particles in the manner of "grafting from" using 3-methacryloxypropyl trimethoxysilane as an intermedia, obtaining the grafted particle polymethacrylic acid PMAA/SiO(2). By adopting the novel surface-molecular imprinting technique put forward by us, cytisine molecule-imprinted material MIP-PMAA/SiO(2) was prepared with ethylene glycol diglycidyl ether as crosslinking agent. The binding characteristics of MIP-PMAA/SiO(2) towards cytisine was investigated in depth with both batch and column methods and using matrine and oxymatrine as two contrast alkaloids, which with cytisine coexist in sophora alopecuroides and their chemical structure is similar to cytisine to a certain extent. The experimental results show that the surface-imprinted material MIP-PMAA/SiO(2) has excellent binding affinity for cytisine (20.1 g/100 g of binding capacity), and it is more important that MIP-PMAA/SiO(2) has very high recognition selectivity for cytisine in relation to the two contrast alkaloids. The selectivity coefficients of the grafted particles PMAA/SiO(2) (non-imprinted material) for cytosine in relation to matrine and oxymatrine are only 1.03 and 1.06, respectively, displaying no recognition selectivity for cytisine. However, after imprinting, the selectivity coefficient of MIP-PMAA/SiO(2) for cytisine in respect to matrine and oxymatrine are remarkably enhanced to 12.08 and 15.05, respectively.

  13. Knowledge, Attitude and Performance of Shiraz General Dentists about Infection Control Principles during Preparing Intraoral Radiographies

    Directory of Open Access Journals (Sweden)

    Abdolaziz Hagh Negahdar

    2017-02-01

    Full Text Available Background & Objective: Infection control in dental centers is affected by the persons’ attitude and knowledge about mechanisms of infection transmission. This study was designed to evaluate the knowledge and the attitude of Shiraz dentists about infection control during intraoral radiographies preparation. Materials & Methods: In this cross-sectional, and analytical research, the attitude and the knowledge of 45 male and 25 female, randomly selected dentists, were obtained through completion of a researcher- planed questioner which its validity and reliability had been confirmed. Data were analyzed using Cronbach`s alpha, one-way ANOVA, student’s t-test, and Pearson’s correlation coefficient in SPSS (V.21. Results: The average of the dentists’ age was 40.59±10.72 and their average occupational experience was 13.49±9.75 years. The mean score obtained for knowledge about infection control during intraoral radiographic procedures was less than fifty percent of total obtainable score, and was assessed as weak knowledge. There was no significant difference in the level of knowledge between studied male and female dentists (P>0.05. In addition, no significant relationship was detected between level, age/experience, and the university of education (P>0.05. The attitude of the dentists about infection control during intraoral radiography preparation assessed as moderate to good level. Conclusions: The results showed that the main reason for the present problems is insufficient knowledge of the dentists in related subjects. Therefore, the solution, which is recommended among dentists, is to raise their awareness and to change their attitudes and culture in order to improve their performance.

  14. Study on the preparation and electrochemical performance of rare earth doped nano-Ni(OH)2

    Institute of Scientific and Technical Information of China (English)

    YE Xiancong; ZHU Yanjuan; WU Shanggai; ZHANG Zhongju; ZHOU Zhuojun; ZHENG Hanzhong; LIN Xiaoran

    2011-01-01

    Multiphase nano-Ni(OH)2 doped with Y or La was prepared by supersonic co-precipitation method.The crystal morphology,structure and particle size were characterized by transmission electron microscopy (TEM),X-ray diffraction (XRD) and particle size distribution (PSD).The electrochemical performance of samples was investigated by electrochemical workstation and battery tested system.The results indicated that micro-morphology and grain size were changed with the changing of supersonic power,pH values and doping elements.The morphology of Y doped sample was from the flake-like to the needle-like with the increase of supersonic power; Particles were from quasispherical particles into needle-like with the increase of pH values; As the supersonic power increased,the proportion of α-Ni(OH)2 increased initially and then decreased.pH value was very important to the formation of crystalline phase.Lower pH value was beneficial to the formation of α-Ni(OH)2.However,the pH values had a slight effect on the reaction reversibility.Complex electrodes were prepared by mixing 8 wt.% nickel hydroxides with commercial micro-size spherical nickel.The discharge capacity of electrodes increased initially and then decreased with the increase of supersonic power.When the supersonic power was 60 W and the pH value was 9,the sample had the largest discharge capacity (358 mAh/g) at 0.5 C rate,which was 122.7 and 76 mAh/g higher than the spherical nickel electrode and La doped sample electrode,respectively.

  15. School District Mergers: What One District Learned

    Science.gov (United States)

    Kingston, Kathleen

    2009-01-01

    Throughout the planning process for a school district merger in a northwestern Pennsylvania school district, effective communication proved to be a challenge. Formed in 1932, this school district of approximately 1400 students was part of a utopian community; one established by a transportation system's corporation that was a major industrial…

  16. Effective connectivity among the working memory regions during preparation for and during performance of the n-back task.

    Directory of Open Access Journals (Sweden)

    Anna eManelis

    2014-08-01

    Full Text Available Recent neuroimaging studies have shown that working memory (WM task difficulty can be decoded from patterns of brain activation in the WM network during preparation to perform those tasks. The inter-regional connectivity among the WM regions during task preparation has not yet been investigated. We examined this question using the graph modeling methods IMaGES and LOFS, applied to the previously published fMRI data of Manelis and Reder (2013. In that study, subjects performed 1-, 2-, and 3-back tasks. Each block of n-back was preceded by a preparation period and followed by a rest period. The analyses of task-related brain activity identified a network of 18 regions that increased in activation from 1- to 3-back (Increase network and a network of 17 regions that decreased in activation from 1- to 3-back (Decrease network. The graph analyses revealed two types of connectivity sub-networks within the Increase and Decrease networks: default and preparation-related. The default connectivity was present not only during task performance, but also during task preparation and during rest. We propose that this sub-network may serve as a core system that allows one to quickly activate cognitive, perceptual and motor systems in response to the relevant stimuli. The preparation-related connectivity was present during task preparation and task performance, but not at rest, and depended on the n-back condition. The role of this sub-network may be to pre-activate a connectivity road map in order to establish a top-down and bottom-up regulation of attention prior to performance on WM tasks.

  17. Effective connectivity among the working memory regions during preparation for and during performance of the n-back task.

    Science.gov (United States)

    Manelis, Anna; Reder, Lynne M

    2014-01-01

    Recent neuroimaging studies have shown that working memory (WM) task difficulty can be decoded from patterns of brain activation in the WM network during preparation to perform those tasks. The inter-regional connectivity among the WM regions during task preparation has not yet been investigated. We examined this question using the graph modeling methods IMaGES and LOFS, applied to the previously published fMRI data of Manelis and Reder (2013). In that study, subjects performed 1-, 2-, and 3-back tasks. Each block of n-back was preceded by a preparation period and followed by a rest period. The analyses of task-related brain activity identified a network of 18 regions that increased in activation from 1- to 3-back (Increase network) and a network of 17 regions that decreased in activation from 1- to 3-back (Decrease network). The graph analyses revealed two types of connectivity sub-networks within the Increase and Decrease networks: "default" and "preparation-related." The "default" connectivity was present not only during task performance, but also during task preparation and during rest. We propose that this sub-network may serve as a core system that allows one to quickly activate cognitive, perceptual and motor systems in response to the relevant stimuli. The "preparation-related" connectivity was present during task preparation and task performance, but not at rest, and depended on the n-back condition. The role of this sub-network may be to pre-activate a connectivity "road map" in order to establish a top-down and bottom-up regulation of attention prior to performance on WM tasks.

  18. Influence of preparation method on performance of a metal supported perovskite catalyst for combustion of methane

    Institute of Scientific and Technical Information of China (English)

    翟彦青; 熊杰明; 李翠清; 徐新; 罗国华

    2010-01-01

    A different method was employed for the preparation of a metal supported perovskite catalyst for the catalytic combustion of methane.The prepared metallic catalysts were characterized by means of X-ray diffractometer(XRD),scanning electron microscopy(SEM),transmission electron microscopy(TEM),and also by ultrasonic and thermal shock tests and catalytic activity.It was found that the process factors during the preparation,e.g.the preparation of the catalyst precursor and the coating slurry,the calcination te...

  19. Preparation of magnetic gelatin-starch microspheres and adsorption performance for bovine serum album

    Institute of Scientific and Technical Information of China (English)

    何秋星; 宋平; 张智萍; 尤卓莹; 涂伟萍

    2015-01-01

    The magnetic gelatin-starch microspheres were prepared by modified emulsion cross-linking method with glutaraldehyde as the cross-linking agent. The structure, size distribution as well as morphology of magnetic microspheres were investigated by FT-IR spectrometer, dynamic laser scattering analyzer and scanning electron microscope, respectively. Bovine serum album (BSA) was chosen as model protein, and the adsorption processes were carried out under diversified conditions including BSA initial concentration, pH value, adsorption time and temperature to evaluate the performance of the magnetic microspheres. The average diameter of optimized spherical magnetic microspheres is 1.6 μm with excellent dispersivity, and the saturation magnetization is found to be equal to 1.056×10−2 A·m2. The adsorption isotherm of the BSA on the magnetic microspheres basically obeys the Langmuir model, with a maximum adsorption capacity of 120 mg/g and an adsorption equilibrium constant of 1.60 mL/mg.

  20. [Preparation of HDTMA-modified Zeolite and Its Performance in Nitro-phenol Adsorption from Wastewaters].

    Science.gov (United States)

    Guo, Jun-yuan; Wang, Bin

    2016-05-15

    In this study, natural zeolite was modified by HDTMA. Effects of the modified conditions, HDTMA-modified zeolite doses, solution pH values, and reaction time on nitro-phenol removal were investigated, and the adsorption kinetics and isotherms were discussed. Compared with natural zeolite, HDTMA-modified zeolite showed better performance in nitro-phenol removal. An adsorption capacity of 2.53 mg · g⁻¹ was achieved when the concentration of HDTMA solution (pH = 10) was 1.2% in preparation of modified zeolite. This adsorption capacity was higher than that obtained by natural zeolite (0.54 mg · g⁻¹). In adsorption tests, when HDTMA- modified zeolite dose was adjusted to 8 g · L⁻¹, the removal efficiency of nitro-phenol reached 93.9% after 90 min reaction, with wastewater pH of 6. Furthermore, the nitro-phenol adsorption process could be well fitted to the pseudo-first-order kinetics model (R² > 0.90), whereas the adsorption isotherm results indicated that Langmuir model provided the best fitting for the equilibrium data at different temperatures, with R² of higher than 0.90.

  1. Nickel foam-supported polyaniline cathode prepared with electrophoresis for improvement of rechargeable Zn battery performance

    Science.gov (United States)

    Xia, Yang; Zhu, Derong; Si, Shihui; Li, Degeng; Wu, Sen

    2015-06-01

    Porous nickel foam is used as a substrate for the development of rechargeable zinc//polyaniline battery, and the cathode electrophoresis of PANI microparticles in non-aqueous solution is applied to the fabrication of Ni foam supported PANI electrode, in which the corrosion of the nickel foam substrate is prohibited. The Ni foam supported PANI cathode with high loading is prepared by PANI electrophoretic deposition, and followed by PANI slurry casting under vacuum filtration. The electrochemical charge storage performance for PANI material is significantly improved by using nickel foam substrate via the electrophoretic interlayer. The specific capacity of the nickel foam-PANI electrode with the electrophoretic layer is higher than the composite electrode without the electrophoretic layer, and the specific capacity of PANI supported by Ni foam reaches up to 183.28 mAh g-1 at the working current of 2.5 mA cm-2. The present electrophoresis deposition method plays the facile procedure for the immobilization of PANI microparticles onto the surface of non-platinum metals, and it becomes feasible to the use of the Ni foam supported PANI composite cathode for the Zn/PANI battery in weak acidic electrolyte.

  2. Preparation and Preliminary Dialysis Performance Research of Polyvinylidene Fluoride Hollow Fiber Membranes

    Directory of Open Access Journals (Sweden)

    Qinglei Zhang

    2015-03-01

    Full Text Available In this study, the separation properties of Polyvinylidene fluoride (PVDF hollow fiber hemodialysis membranes were improved by optimizing membrane morphology and structure. The results showed that the PVDF membrane had better mechanical and separation properties than Fresenius Polysulfone High-Flux (F60S membrane. The PVDF membrane tensile stress at break, tensile elongation and bursting pressure were 11.3 MPa, 395% and 0.625 MPa, respectively. Ultrafiltration (UF flux of pure water reached 108.2 L∙h−1∙m−2 and rejection of Albumin from bovine serum was 82.3%. The PVDF dialyzers were prepared by centrifugal casting. The influences of membrane area and simulate fluid flow rate on dialysis performance were investigated. The results showed that the clearance rate of urea and Lysozyme (LZM were improved with increasing membrane area and fluid flow rate while the rejection of albumin from bovine serum (BSA had little influence. The high-flux PVDF dialyzer UF coefficient reached 62.6 mL/h/mmHg. The PVDF dialyzer with membrane area 0.69 m2 has the highest clearance rate to LZM and urea. The clearance rate of LZM was 66.8% and urea was 87.7%.

  3. Preparation, characterization, and photocatalytic performance of Ce2S3 for nitrobenzene reduction

    Science.gov (United States)

    Chen, Shifu; Zhang, Huaye; Fu, Xianliang; Hu, Yingfei

    2013-06-01

    Ce2S3 photocatalysts were synthesized by a co-precipitation method using cerium nitrate and thioacetamide as raw materials. The samples were characterized by X-ray powder diffraction analysis, UV-visible diffuse reflectance spectroscopy, scanning electron microscopy, and differential thermal analysis. Photocatalytic reduction of nitrobenzene (NB) under UV or visible light illumination was used to evaluate the photocatalytic activity of the Ce2S3 samples. The result indicated that the sample prepared at 300 °C for 12 h exhibited the highest activity. For 140 mL 8.13 × 10-4 mol/L of NB in methanol solvent, after illumination for 5 h, about 43.9% and 34.7% of NB were reduced to aniline over the sample under UV and visible light irradiation, respectively. The effects of the catalyst amount, illumination time, and sorts of solvent on the photocatalytic performance were investigated specifically. The reduction process of NB over Ce2S3 was finally discussed.

  4. Enhanced performance of microbial fuel cell with in situ preparing dual graphene modified bioelectrode.

    Science.gov (United States)

    Chen, Junfeng; Hu, Yongyou; Tan, Xiaojun; Zhang, Lihua; Huang, Wantang; Sun, Jian

    2017-10-01

    This study proposed a three-step method to prepare dual graphene modified bioelectrode (D-GM-BE) by in situ microbial-induced reduction of GO and polarity reversion in microbial fuel cell (MFC). Both graphene modified bioanode (GM-BA) and biocathode (GM-BC) were of 3D graphene/biofilm architectures; the viability and thickness of microbial biofilm decreased compared with control bioelectrode (C-BE). The coulombic efficiency (CE) of GM-BA was 2.1 times of the control bioanode (C-BA), which demonstrated higher rate of substrates oxidation; the relationship between peak current and scan rates data meant that GM-BC was of higher efficiency of catalyzing oxygen reduction than the control biocathode (C-BC). The maximum power density obtained in D-GM-BE MFC was 122.4±6.9mWm(-2), the interfacial charge transfer resistance of GM-BA and GM-BC were decreased by 79% and 75.7%. The excellent electrochemical performance of D-GM-BE MFC was attributed to the enhanced extracellular electron transfer (EET) process and catalyzing oxygen reduction. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Potassium vapor assisted preparation of highly graphitized hierarchical porous carbon for high rate performance supercapacitors

    Science.gov (United States)

    Liu, Zheng; Zeng, Ying; Tang, Qunli; Hu, Aiping; Xiao, Kuikui; Zhang, Shiying; Deng, Weina; Fan, Binbin; Zhu, Yanfei; Chen, Xiaohua

    2017-09-01

    Ultrahigh graphitized carbon microspheres with rich hierarchical pores (AGHPCM-1) have been successfully synthesized through the one-step activation-carbonization strategy (OACS) with porous sulfonated poly-divinylbenzene as the carbon precursor, iron as the hard template and catalyst, and potassium hydroxide (KOH) as activation agent. Through the XRD, TEM, Raman and BET analysis, AGHPCM-1 shows very high graphitization degree and rich micro-, meso- and macro-pores. More importantly, the mechanism for KOH to improve the graphitization degree of carbon materials in OACS has been illustrated by the thermodynamical theory. The tremendous heat releasing from the reaction between the catalyst precursor of Fe2O3 and potassium vapor plays a key role in the formation of graphitized carbon. It may provide a general direction to prepare highly graphitized porous carbon at a moderate temperature. Integrating the advantages of high graphitization degree and rich hierarchical porous structure, the AGHPCM-1 exhibits an excellent rate performance with a response to up to the high current density of 150 A g-1 and high scan rate of 2000 mV s-1. No obvious capacitance decay can be observed after 10000 charge/discharge cycles even at the high current density of 20 A g-1.

  6. Preparation and Performance of Asphalt Compound Modified with Waste Crumb Rubber and Waste Polyethylene

    Directory of Open Access Journals (Sweden)

    Yuqiao Yang

    2016-01-01

    Full Text Available Three kinds of modified asphalt were prepared by adding waste crumb rubber (WCR, waste polyethylene (WPE, and WCR/WPE to base asphalt, respectively. The influence of different doses on the performance of modified asphalt, such as 25°C penetration, softening point, 5°C ductility, and 135°C, 165°C viscosity, was studied, and the modification mechanism of modified asphalt was discussed through the fluorescence microscope. As the waterproofing materials, the waterproofness of WCR/WPE compound modified asphalt was tested. The results show that the WPE modified asphalt has excellent resistance to high temperature and WCR modified asphalt has good low temperature resistance. The resistance to deformation ability of WPE modified asphalt is better than that of the WCR modified asphalt. The 135°C viscosity of compound modified asphalt is better than that of WPE and WCR modified asphalt. In addition, the waterproofness of compound modified asphalt using waterproofing materials is better than that of common waterproofing materials.

  7. Preparation of a self-humidifying membrane electrode assembly for fuel cell and its performance analysis

    Institute of Scientific and Technical Information of China (English)

    王诚; 毛宗强; 徐景明; 谢晓峰; 杨立寨

    2003-01-01

    A novel nano-porous material SiO2-gel was prepared. After being purified by H2O2, then protonized by H2SO4 and desiccated in vacuum, the SiO2-gel, mixed with Nafion solution, was coated between an electrode and a solid electrolyte, which made a new type of self-humidifying membrane electrode assembly. The SiO2 powder was characterized by FTIR, BET and XRD. The surface of the electrodes was characterized by SEM and EDS. The performances of the self-hu- midifying membrane electrodes were analyzed by polarization discharge and AC impedance under the operation modes of external humidification and self-humidification respectively. Experimental results indicated that the SiO2 powder held super-hydrophilicity, and the layer of SiO2 and Nafion polymer between electrode and solid electrolyte expanded three-dimension electrochemistry reaction area, maintained stability of catalyst layer and enhanced back-diffusion of water from cathode to anode, so the PEM Fuel cell can generate electricity at self-humidification mode. The power density of single PEM fuel cell reached 1.5 W/cm2 under 0.2 Mpa, 70℃ and dry hydrogen and oxygen.

  8. Preparation and Performance of Rare Earths Chemical Conversion Film on Magnesium Alloy

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Golden yellow cerium conversion film was obtained on magnesium alloys surface by immersion method and the preparation parameters were established. The influence of different process parameters on the surface morphology and performance of the conversion film were analyzed by means of SEM and electrochemical method. Formation dynamics about cerium conversion film on magnesium alloy in solution containing cerium salt and the anti-corrosion behavior of the conversion film in 3.5% NaCl solution were studied by electrochemical method respectively. The results shows that the conversion film is more compact at room temperature when concentration of cerium sulfate is 10 g·L-1 in the solution; the open circuit potential of the magnesium sample moves up to positive direction about 100 mV, the surface of conversion film becomes even and lustrous, and the adhesion intensity of conversion film increases when adding aluminum nitrate into the solution containing cerium salt. The pH value of the solution and immersion time of the sample in the solution also affect the surface morphology and anti-corrosion property of the conversion film. After covered by rare earths conversion film, the anti-corrosion property of magnesium alloy is obviously improved. Rare earth conversion film has self-repairing capability in corrosion medium.

  9. Preparation and photocatalytic performance of ZrO{sub 2} nanotubes fabricated with anodization process

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Wei, E-mail: weijiang@scu.edu.cn; He, Jian; Zhong, Jiemin; Lu, Jiuyun; Yuan, Shaojun; Liang, Bin

    2014-07-01

    Anodization process is a facile method to prepare structured nano-material. In this research, anodization process of zirconium in (NH{sub 4}){sub 2}SO{sub 4}/NH{sub 4}F solution was studied systematically and the anodized zirconia was applied to degrade methyl orange (MO) solution under UV irradiation and compared with anodized titania nanotubes to determine the photoactivity of zirconia nanotubes. After anodization in aqueous electrolyte containing 1 M (NH{sub 4}){sub 2}SO{sub 4} and 0.25 wt% NH{sub 4}F for 120 min at 20 V, zirconia nanotubes (ZNT) with diameters of about 20 nm and lengths of about 600 nm were formed. The growth mechanism of ZNT was studied with SEM and TEM. The hypothesis of ZNT growth, in which electric etching process started at the pits and further to deepen in situ to form nanotubes, was confirmed by the SEM. The anodization process on the sanded rough Zr foil verified this assumption since the growth of ZNT occurred at the bottom of the ripples on Zr foil and gathered to form bundles at the peaks. The as-grown ZNT is a mixture of monoclinic and tetragonal ZrO{sub 2} crystals, which transforms into pure monoclinic structure after annealed at 300 °C. The unannealed ZNT has excellent photocatalytic performance with a MO photo-degradation rate of 94.45% after 4 h, even if contrasting to anodized titania. Reusing experiments confirmed that the decaying of photocatalytic performance of ZNT can be negligible in 6 times recycling.

  10. Preparation and investigation of nano-AlN lubricant with high performance

    Energy Technology Data Exchange (ETDEWEB)

    Tao, Yu; Tao, Yuxiao; Wang, Biaobing [School of Materials Science and Engineering, Changzhou University, Changzhou 201326 (China); Tai, Yanlong, E-mail: ytai@ucdavis.edu [Department of Biomedical Engineering, University of California Davis, Davis, CA 95616 (United States)

    2014-09-15

    A new kind of macromolecular coupling agent (LMW-a-PP-g-MAH) of maleic anhydride (MAH) onto low-molecular-weight atactic polypropylene (LMW-a-PP) was synthesized according to molecular design and was used as modifier for surface modification of nano-Aluminum nitride (AlN) by a high-pressure homogenization (HPH) process. IR was conducted to confirm the chemical structure of the step products of LMW-a-PP-g-MAH. The availability as a modifier for surface modification of nano-AlN was distinguished by Fourier transform infrared spectroscopy (FTIR), particle size analysis, transmission electron microscope (TEM), thermogravimetric analysis (TGA), contact angle experiments and the dispersion stability in dimethylbenzene and Greatwall lubrication oil. It can be inferred that the optimal loading is 10 wt. %–12 wt. % of LMW-a-PP-g-MAH to modify nano-AlN particles. Nano-AlN lubricating composite materials (LMW-a-PP-g-MAH-AlN) was used to improve the antifriction performance and the load capability of Greatwall lubrication oil, and maximum non-seizure load (P{sub B}) can increase highly from 1000 N to 1490 N when the loading is 0.3 wt. %. - Highlights: • Design and synthesis of macromolecular coupling agent (a-PP-g-MAH). • Surface modification and characterization of nano-AlN by HPH process. • Preparation and investigation of nano-AlN/lubricating oil with high performance.

  11. LHCb Vertex Locator: Performance and radiation damage in LHC Run 1 and preparation for Run 2

    Science.gov (United States)

    Szumlak, T.; Obła˛kowska-Mucha, A.

    2016-07-01

    LHCb is a dedicated experiment to study New Physics in the decays of heavy hadrons at the Large Hadron Collider (LHC) at CERN. Heavy hadrons are identified through their flight distance in the Vertex Locator (VELO). The VELO comprises 42 modules made of two n+-on-n 300 μm thick half-disc silicon sensors with R- and Φ-measuring micro-strips. In order to allow retracting the detector, the VELO is installed as two movable halves containing 21 modules each. The detectors are operated in a secondary vacuum and are cooled by a bi-phase CO2 cooling system. During data taking in LHC Run 1 the LHCb VELO has operated with an extremely high efficiency and excellent performance. The track finding efficiency is typically greater than 98%. An impact parameter resolution of less than 35 μm is achieved for particles with transverse momentum greater than 1 GeV/c. An overview of all important performance parameters will be given. The VELO sensors have received a large and non-uniform radiation dose of up to 1.2 ×1014 1 MeV neutron equivalent cm-2 during the first LHC run. Silicon type-inversion has been observed in regions close to the interaction point. The preparations for LHC Run 2 are well under way and the VELO has already recorded tracks from injection line tests. The current status and plans for new operational procedures addressing the non-uniform radiation damage are shortly discussed.

  12. Assessing the Distribution of Fiscal and Personnel Resources across Schools. A Report Prepared for Pasadena Unified School District. SSFR Research Report #01 (PUSD)

    Science.gov (United States)

    Chambers, Jay G.; Levin, Jesse; Brodziak, Iliana; Chan, Derek

    2010-01-01

    As a starting point for their analysis of equity, the authors begin their work here with an examination of the relationship between student performance, as measured by the California Academic Performance Index (API), and student needs, as measured by the percentage of students from low-income families (i.e., the percent of students eligible for…

  13. 36 CFR 28.3 - Boundaries: The Community Development District; The Dune District; The Seashore District.

    Science.gov (United States)

    2010-07-01

    ... Development District; The Dune District; The Seashore District. 28.3 Section 28.3 Parks, Forests, and Public... General Provisions § 28.3 Boundaries: The Community Development District; The Dune District; The Seashore... Community Development District, the Seashore District, and the Dune District. (b) The Community...

  14. Factors associated with tuberculosis cases in Semarang District, Indonesia: case-control study performed in the area where case detection rate was extremely low.

    Science.gov (United States)

    Rahayu, Sri Ratna; Katsuyama, Hironobu; Demura, Masashi; Katsuyama, Midori; Ota, Yoko; Tanii, Hideji; Higashi, Tomomi; Semadi, Ngakan Putu Djaja; Saijoh, Kiyofumi

    2015-07-01

    Indonesia is ranked as the 4th highest contributor to tuberculosis (TB) in the world. Semarang District in Central Java displays extremely low case detection rate (CDR), possibly contributing to the local prevalence of TB. A case-control study was performed to explore the factors that cause such low CDR. We recruited 129 TB cases and 83 controls that visited the same centers and were not diagnosed with TB. The cases had 7.5 ± 2.3 symptoms/person on average, indicating the delay in diagnosis because the controls only displayed 1.0 ± 1.7. The multiple logistic regression analysis comparing the cases/controls extracted following factors as a risk to have TB: farmer, close contact with TB patients, ignorance of whether Bacillus Calmette-Guérin (BCG) was accepted or no, smoking, low income, a lot of people living in the same room, irregular hand wash before meals, not wash hands after blow, soil floor, and no sunlight and no ventilation in the house. Neither the cases nor the controls knew the symptoms and how to avoid TB infection, which probably caused the delay in diagnosis. It is difficult to change the current living conditions. Thus, the amendment of the community-based education program of TB seems to be required.

  15. Annual measured and simulated thermal performance analysis of a hybrid solar district heating plant with flat plate collectors and parabolic trough collectors in series

    DEFF Research Database (Denmark)

    Tian, Zhiyong; Perers, Bengt; Furbo, Simon

    2017-01-01

    in large solar heating plants for a district heating network, a hybrid solar collector field with 5960 m2 flat plate collectors and 4039 m2 parabolic trough collectors in series was constructed in Taars, Denmark. The design principle is that the flat plate collectors preheat the return water from...... for this type of hybrid solar district heating plants with flat plate collectors and parabolic trough collectors in the Nordic region, but also introduce a novel design concept of solar district heating plants to other high solar radiation areas.......Flat plate collectors have relatively low efficiency at the typical supply temperatures of district heating networks (70–95 °C). Parabolic trough collectors retain their high efficiency at these temperatures. To maximize the advantages of flat plate collectors and parabolic trough collectors...

  16. Preparation of high dispersion and high performance PtRu/CNTs catalyst by an organic colloid method

    Institute of Scientific and Technical Information of China (English)

    王宁卡特; 刘军民; 廖世军; V.Birss

    2006-01-01

    A high dispersion and high performance PtRu catalyst supported on carbon nanotubes was prepared by an organic colloid method. The particle size of the active components could be as small as 1.0 nm,the active surface area was about 466 m2/g(Pt). The catalytic activity toward anodic oxidation of methanol was about 3 ~ 4 times higher than that of Johnson Matthey PtRu/XC-72R catalyst. The single testing showed that the performance of the prepared catalyst was higher than that of the commercial one.

  17. A novel preparation procedure of future weather datasets for building performance simulation

    Science.gov (United States)

    Huang, Kuo-Tsang; Chuang, Kai-Han

    2014-05-01

    a given future period under certain climate change scenarios should be identified. The GCMs provided by the World Climate Research Program's (WCRP) Coupled Model Intercomparison Project Phase 3 (CMIP3) were used to calculate these changes of every accounted meteorological elements that need to be morphed. Since these GCMs may deviates substantially, one might choose an appropriate GCM prior to the morphing procedure. Therefore, to identify the GCM that project well against actual local climate trends, principle component analysis (PCA) was introduced. First principle component of each GCM predicted weather data as well as the observed data from the same period were obtained by PCA. Afterwards, root mean square deviation (RMSD) was used to identify the GCM that suits local trends. The results show that the morphed TMYs agree well with the observed data during the validation process, revealing that the proposed procedure of future weather preparation for building simulation is reliable and also feasible. Hourly future weather datasets for the purpose of building performance simulation for northern and southern Taiwan with two greenhouse gas emission scenarios covering three future timeframes (i.e. 2030s, 2050s, 2080s) were established and discussed herein.

  18. Portfolio Assessment in the Preparation of School Administrators.

    Science.gov (United States)

    Wilmore, Elaine L.; Erlandson, David A.

    Texas A&M University at College Station (A&M) and the University of Texas at Arlington (UTA) employed portfolio assessment in their field-based principal preparation programs using the 21 performance domains of the National Policy Board for Educational Administration. In a joint venture with the Bryan Independent School District, selected…

  19. Preparing Students for Critical-Thinking Applications on Standardized Tests

    Science.gov (United States)

    Hendricks, Jacquelyn Kaye

    2010-01-01

    Student performance on critical-thinking applications on standardized tests in a southwestern U.S. state has been low for several years. The purpose of this instrumental case study was to explore how one school district prepared students for critical-thinking applications on standardized tests. The study was informed by cognitivism and…

  20. Preparing Students for Critical-Thinking Applications on Standardized Tests

    Science.gov (United States)

    Hendricks, Jacquelyn Kaye

    2010-01-01

    Student performance on critical-thinking applications on standardized tests in a southwestern U.S. state has been low for several years. The purpose of this instrumental case study was to explore how one school district prepared students for critical-thinking applications on standardized tests. The study was informed by cognitivism and…

  1. Preparation and characterizations of activated carbon monolith from rubber wood and its effect on supercapacitor performances

    Science.gov (United States)

    Taer, E.; Taslim, R.; Deraman, M.

    2016-02-01

    Preparation of activated carbon monolith (ACM) from rubber wood was investigated. Two kind of preparation method were carried out by pre-carbonized of rubber wood saw dust and rubber wood material as it is naturally. The samples were prepared with pelletizing method and small cutting of rubber wood in cross sectional method. Both of samples were characterized by physical and electrochemical technique. The physical properties such as morphology and porosity were investigated. The electrochemical properties of both samples such as equivalent series resistances (ESR) and specific capacitances were also compared. In conclusion, this study showed that both of different preparation method would propose a simple method of ACM electrode preparation technique for supercapacitor applications.

  2. Synthesis of robust and high-performance aquaporin-based biomimetic membranes by interfacial polymerization-membrane preparation and RO performance characterization

    DEFF Research Database (Denmark)

    Zhao, Yang; Qiu, Changquan; Li, Xuesong

    2012-01-01

    Aquaporins are water channel proteins with excellent water permeability and solute rejection, which makes them promising for preparing high-performance biomimetic membranes. Despite the growing interest in aquaporin-based biomimetic membranes (ABMs), it is challenging to produce robust and defect...

  3. Effect of preparation methods of aluminum emulsions on catalytic performance of copper-based catalysts for methanol synthesis from syngas

    Institute of Scientific and Technical Information of China (English)

    Lili Wang; Wen Ding; Yingwei Liu; Weiping Fang; Yiquan Yang

    2010-01-01

    Various Cu/ZnO/Al2O3 catalysts have been synthesized by different aluminum emulsions as aluminum sources and their performances for methanol synthesis from syngas have been investigated.The influences of preparation methods of aluminum emulsions on physicochemical and catalytic properties of catalysts were studied by XRD,SEM,XPS,N2 adsorption-desorption techniques and methanol synthesis from syngas.The preparation methods of aluminum emulsions were found to influence the catalytic activity,CuO crystallite size,surface area and Cu0 surface area and reduction process.The results show that the catalyst CN using the aluminum source prepared by addition the ammonia into the aluminum nitrate (NP) exhibited the best catalytic performance for methanol synthesis from syngas.

  4. Preparation, thermal performance and application of shape-stabilized PCM in energy efficient buildings

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Y.P.; Lin, K.P.; Di, H.F.; Jiang, Y. [Tsinghua Univ., Beijing (China). Dept. of Building Science and Technology; Yang, B. [Tsinghua Univ., Beijing (China). Dept. of Chemical Engineering

    2006-10-15

    Shape-stabilized phase change material (PCM) is a kind of novel PCM. It has the following salient features: large apparent specific heat for phase change temperature region, suitable thermal conductivity, keeping shape stabilized in the phase change process and no need for containers. The preparation for such kind material was investigated and its thermophysical properties were measured. Some applications of such material in energy efficient buildings (e.g., in electric under floor space heating system, in wallboard or floor to absorb solar energy to narrow the temperature swing of a day in winter) were studied. Some models of analyzing the thermal performance of the systems were developed, which were validated with the experiments. The following conclusions are obtained: (1) the applications of the novel PCM we put forward are of promising perspectives in some climate regions; (2) by using different paraffin, the melting temperature of shape-stabilized PCM can be adjusted; (3) the heat of fusion of it is in the range of 62-138 kJ kg{sup -1}; (4) for PCM floor or wallboard to absorb solar energy to narrow the temperature swing in a day in winter, the suitable melting temperature of PCM should be a little higher than average indoor air temperature of the room without PCM for the period of sunshine; (5) for the electric under-floor space heating system, the optimal melting temperature can be determined by simulation; (6) PCM layer used in the aforementioned application should not be thicker than 2 cm; (7) the models developed by us are helpful for applications of shape-stabilized PCM in buildings. (author)

  5. Preparation of porous Al2O3-Ti-C perform by combustion synthesis

    Directory of Open Access Journals (Sweden)

    K.Granat

    2009-04-01

    Full Text Available Using combustion synthesis porous ceramic preforms for composite reinforcing were produced. Prepared mixture of alumina Saffilfibres, Ti powder and graphite flakes, after drying were placed in waveguide of microwave reactor. Supplied with constant power of 540Wmagnetron ignited and maintained reaction in flowing stream of CO2 gas. Al2O3 fibres should improve preliminary endurance of perform,whereas Ti powder processed to hard titanium carbides and oxides. During microwave heating ignited plasma additionally improveprocess and partly fused metallic Ti. Recorded temperature curves were similar for various samples. The highest synthesis temperature revealed samples containing 10% of Al2O3 , 10% of Ti and 5% of graphite, all percentages atomic. Microscopic observation showed considerable microstructure inhomogeneity of some samples. Both irregular component ordering and partly processed Ti particles inside preform exclude them for subsequent infiltration. Chemical analyze EDS of Ti based compounds partly confirmed work purpose, evidencing presence of Ti oxides and carbides. Independently of graphite content these compounds formed folded strips around solid or empty volume. Depends on CO2 availability, reaction could be slowed down resulting in more compacted Ti compounds. Created as a result of combustion synthesis Ti compound after infiltration with liquid metal properly bounded with the matrix. It could be assumed that redox reaction proceeded and on surface of Ti compound alumina and Al-Ti compounds were created. The preforms of proper strength and homogeneous structure were infiltrated with AlSi7Mg by squeeze casting method. In relation to typical composite reinforced only with fibres no significant increase of defects quantity was observed. Preliminary examination of mechanical properties confirmed that assumed work purpose is reasonable.

  6. Preparation and visible-light photocatalytic performances of cyclized polyacrylonitrile/TiO2 nanocomposites

    OpenAIRE

    Wang, Xiaojing; Wang, Lin; Qingzhi LUO; Wang, Peng; Xu, Li; Desong WANG

    2015-01-01

    TiO2 nanomaterials were prepared by a conventional sol-gel method with tetrabutyl titanate as Ti source. The polyacrylonitrile solution with dimethyl sulfoxide as solvent was added into TiO2 sols to form TiO2 gels containing polyacrylonitrile, then the as-prepared TiO2 gels were heat-treated to prepare cyclized polyacrylonitrile/TiO2 (CPAN/TiO2) nanocomposites. The CPAN/TiO2 nanocomposites were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), UV-vis diffuse re...

  7. Utilization of central nervous system resources for preparation and performance of complex walking tasks in older adults

    Directory of Open Access Journals (Sweden)

    David J Clark

    2014-08-01

    Full Text Available IntroductionWalking in the home and community often involves performance of complex walking tasks. Understanding the control of such tasks is crucial to preserving independence and quality of life in older adults. However, very little research has been conducted in this area. Here we assess the extent to which two measures of central nervous system (CNS activity are responsive to the challenges posed by preparation and performance of complex walking tasks. Prefrontal cortical activity was measured by functional near infrared spectroscopy (fNIRS and sympathetic nervous system arousal was measured by skin conductance level (SCL.Materials and MethodsSixteen older men and women (age 77.2 ± 5.6 years with mild mobility deficits participated in this study. Participants walked at their preferred speed without distractions along an unobstructed, well-lit course (control task and also walked on the same course under five separate challenging conditions: performing a cognitive verbal fluency task (verbal task, dim lighting (dim task, carrying a tray (carry task, negotiating obstacles (obstacles task and wearing a weighted vest (vest task. Mean prefrontal activation and SCL were calculated during the preparation and performance phases of each task. Gait spatiotemporal measurements were acquired by an instrumented gait mat.ResultsPrefrontal cortical activity and SCL were elevated during the preparation phase of complex walking tasks relative to the control task. During the performance phase, prefrontal activity remained elevated to a similar level as during task preparation. In contrast, SCL continued to increase beyond the level observed during task preparation. A larger increase in prefrontal activity was found to be linked to preserved quality of gait during complex walking tasks.DiscussionThese findings indicate that availability and utilization of CNS resources are important for optimizing performance of complex walking tasks in older adults.

  8. Improved electrochemical performances of CuO nanotube array prepared via electrodeposition as anode for lithium ion battery

    Energy Technology Data Exchange (ETDEWEB)

    Xiao, Anguo, E-mail: hixiaoanguo@126.com; Zhou, Shibiao; Zuo, Chenggang; Zhuan, Yongbing; Ding, Xiang

    2015-10-15

    Graphical abstract: CuO nanotube array electrodes prepared by electrodeposition method exhibit an excellent lithium ion storage ability as anode of Li-ion battery. - Highlights: • CuO nanotube arrays are synthesized by an electrodeposition method. • CuO nanotube shows a high-rate performance. • CuO nanotube shows an excellent cycling performance. - Abstract: We report a facile strategy to prepared CuO nanotube arrays directly grown on Cu plate through the electrodeposition method. The as-prepared CuO nanotubes show a quasi-cylinder nanostructure with internal diameters of ca. ∼100 nm, external diameters of ca. ∼120 nm, and average length of ∼3 μm. As an anode for lithium ion batteries, the electrochemical properties of the CuO nanotube arrays are investigated by cyclic voltammetry (CV) and galvanostatic charge/discharge tests. Due to the unique nanotube nanostructure, the as-prepared CuO electrodes exhibit good rate performance (550 mAh g{sup −1} at 0.1 C and 464 mAh g{sup −1} at 1 C) and cycling performance (581 mAh g{sup −1} at 0.1 C and 538 mAh g{sup −1} at 0.5 C)

  9. Selection and Maintenance of Stimulus-Response Rules during Preparation and Performance of a Spatial Choice-Reaction Task

    Science.gov (United States)

    Schumacher, Eric H.; Cole, Michael W.; D’Esposito, Mark

    2007-01-01

    The ability to select an appropriate response among competing alternatives is a fundamental requirement for successful performance of a huge variety of everyday tasks. Recent research suggests that a frontal-parietal network of brain regions (including dorsal prefrontal, dorsal premotor and superior parietal cortices) mediate response selection for spatial material. Most of this research has used blocked experimental designs. Thus, the frontal-parietal activity reported may be due either to tonic activity across a block or to processing occurring at the trial level. Our current event-related fMRI study investigated response selection at the level of the trial in order to identify possible response selection sub-processes. In the study, participants responded to a visually presented stimulus with either a spatially compatible or incompatible manual response. On some trials, several seconds prior to stimulus onset, a cue indicated which task was to be performed. In this way we could identify separate brain regions for task preparation and task performance, if they exist. Our results showed that the frontal-parietal network for spatial response selection activated both during task preparation as well as during task performance. We found no evidence for preparation specific brain mechanisms in this task. These data suggest that spatial response selection and response preparation processes rely on the same neurocognitive mechanisms. PMID:17223091

  10. Preparation and Antiflame Performance of Expandable Graphite Modified with Sodium Hexametaphosphate

    National Research Council Canada - National Science Library

    Zhao, Hongmei; Pang, Xiuyan; Zhai, Zhixiao

    2015-01-01

    A kind of polyphosphate modified expandable graphite (EGp) was prepared in graphite oxidation and intercalation reaction with KMnO4 as oxidant, H2SO4 as intercalator, and sodium hexametaphosphate (SHMP...

  11. Preparation of reactive macroporous polymeric beads for high-performance liquid chromatography applications: Polymerization, surface modification and characterization

    Science.gov (United States)

    Liang, Yi-Chun

    Several stationary phases for high performance liquid chromatography (HPLC) based on synthetic polymers with controlled pore structures and surface chemistries have been prepared and characterized. The first part of the research is focused on the control of pore structure of reactive beads prepared from functional monomers such as 2,3-epoxypropyl vinylbenzyl ether and 2,3-epoxypropyl vinylbenzyl ether with divinylbenzene used as a crosslinker. Due to a relatively large difference in polarities of these two functional monomers, a new porogenic system had to be developed for the preparation of monodisperse beads from 2,3-epoxypropyl vinylbenzyl ether. In contrast, polymerization conditions similar to those used for the preparation of poly(styrene-co-divinylbenzene) beads can be used for the systems involving chloromethylstyrene and divinylbenzene. An extensive study of the effects of various polymerization parameters on the properties of these reactive beads was carried out in order to achieve fine control over the degree of functionalization and pore structure. The second part of the research is focused on the surface modification of reactive beads prepared in the previous study for the HPLC separation of enantiomers. The performance of our chiral stationary phases (CSP) with brush-type selectors was comparable to the best silica-based chiral separation media. As a part of this study, polymeric CSPs with different linkages, tethers, loading levels, and backbone structures were prepared and characterized. Another series of CSPs were prepared from beads functionalized with a poly(propylene imine) dendrimer tether. A high coupling efficiency with the chiral selector was characteristic of the polymer support modified with dendrimers, and these dendritic supports demonstrated the substantial contribution of linkers with multiple functionalities originating from a single surface site to the selectivity and efficiency of the polymer based separation media.

  12. District Fiscal Policy and Student Achievement

    Directory of Open Access Journals (Sweden)

    Gary G. Huang

    2002-09-01

    Full Text Available School restructuring raises questions about the role of school districts in improving student learning. Centralization by state governments and decentralization to individual schools as proposed in systemic reform leave districts' role unsettled. Empirical research on the district role in the context of ongoing reform is inadequate. This analysis of combined data from the NAEP and the Common Core of Data (CCD was intended to address the issue. We analyzed 1990, 1992, and 1996 NAEP 8th grade mathematics national assessment data in combination with CCD data of corresponding years to examine the extent to which student achievement was related to districts' control over instructional expenditure, adjusting for relevant key factors at both district and student levels. Upon sample modification, we used hierarchical linear modeling (HLM to estimate the relationships of student achievement to two district fiscal policy indictors, current expenditure per pupil (CEPP and districts' discretionary rates for instructional expenditure (DDR. Net of relevant district factors, DDR was found unrelated to districts' average 8th grade math performance. The null effect was consistent in the analysis of the combined NAEP-CCD data for 1990, 1992, and 1996. In contrast, CEPP was found related to higher math performance in a modest yet fairly consistent way. Future research may be productive to separately study individual states and integrate the findings onto the national level.

  13. Study on anti-pollution nano-preparation of dimethomorph and its performance

    Institute of Scientific and Technical Information of China (English)

    YAN Jianhui; HUANG Kelong; WANG Yuelong; LIU Suqin

    2005-01-01

    The photocatalysis of nanometer TiO2/Ag was modified by sodium dodecyl sulfate, and its behavior of adsorption for pesticide was investigated on the surface of catalyst. Four kinds of water-solubility preparations were prepared by using TiO2/Ag, modified TiO2/Ag by 0.5% SDS,TiO2 and nothingness as photocatalyst with dimethomorph as effective component. They were besmeared on a piece of glass, and the photocatalytic experiment was done in sunlight.Degradation rates of 1.2% dimethomorph are 71.5%, 68.0%,45.5% and 28.3%, respectively, when it was degraded in five days. Degradation rate of 10% dimethomorph is 97.3% in eight days in sunlight and t1/2 is 2.8 d in nano-preparation,when it was sprayed on small cabbages after being diluted in rudimental experiments of toxicity for crop. The nano-preparation is of better biologic activity, the virulence of which is 1.235 times as great as original pesticide and 1.245 times as ordinary preparation under the same condition.

  14. MnO2 prepared by hydrothermal method and electrochemical performance as anode for lithium-ion battery.

    Science.gov (United States)

    Feng, Lili; Xuan, Zhewen; Zhao, Hongbo; Bai, Yang; Guo, Junming; Su, Chang-Wei; Chen, Xiaokai

    2014-01-01

    Two α-MnO2 crystals with caddice-clew-like and urchin-like morphologies are prepared by the hydrothermal method, and their structure and electrochemical performance are characterized by scanning electron microscope (SEM), X-ray diffraction (XRD), galvanostatic cell cycling, cyclic voltammetry, and electrochemical impedance spectroscopy (EIS). The morphology of the MnO2 prepared under acidic condition is urchin-like, while the one prepared under neutral condition is caddice-clew-like. The identical crystalline phase of MnO2 crystals is essential to evaluate the relationship between electrochemical performances and morphologies for lithium-ion battery application. In this study, urchin-like α-MnO2 crystals with compact structure have better electrochemical performance due to the higher specific capacity and lower impedance. We find that the relationship between electrochemical performance and morphology is different when MnO2 material used as electrochemical supercapacitor or as anode of lithium-ion battery. For lithium-ion battery application, urchin-like MnO2 material has better electrochemical performance.

  15. MnO2 prepared by hydrothermal method and electrochemical performance as anode for lithium-ion battery

    Science.gov (United States)

    2014-01-01

    Two α-MnO2 crystals with caddice-clew-like and urchin-like morphologies are prepared by the hydrothermal method, and their structure and electrochemical performance are characterized by scanning electron microscope (SEM), X-ray diffraction (XRD), galvanostatic cell cycling, cyclic voltammetry, and electrochemical impedance spectroscopy (EIS). The morphology of the MnO2 prepared under acidic condition is urchin-like, while the one prepared under neutral condition is caddice-clew-like. The identical crystalline phase of MnO2 crystals is essential to evaluate the relationship between electrochemical performances and morphologies for lithium-ion battery application. In this study, urchin-like α-MnO2 crystals with compact structure have better electrochemical performance due to the higher specific capacity and lower impedance. We find that the relationship between electrochemical performance and morphology is different when MnO2 material used as electrochemical supercapacitor or as anode of lithium-ion battery. For lithium-ion battery application, urchin-like MnO2 material has better electrochemical performance. PMID:24982603

  16. Preparation of a Novel Coal Gangue-Polyacrylamide Hybrid Flocculant and Its Flocculation Performance

    Institute of Scientific and Technical Information of China (English)

    Xiangao Quan; Huiyun Wang

    2014-01-01

    A novel flocculant based on hybrid coal gangue-polyacrylamide (HCGPAM) has been prepared by using modified coal gangue and polyacrylamide. Factors related to the preparation such as reaction time, temperature, concentration of the polymer monomer and ratio of initiators are investigated. The product is characterized by infrared spectra (FTIR), scanning electron microscopy (SEM), X-ray diffraction (XRD), aswell as viscometry. The flocculating tests on oilfield drilling wastewater show that the removal efficiency is 85.5% and the light transmittance is 53.6%. The results indicate that the coal gangue could be used for the preparation of inorganic-organic hybrid flocculant and the removal efficiency is much higher than that of commercial polyacrylamide (PAM) or PAM/ coal gangue blend.

  17. Preparation and performance of ZnO/Polyaniline nano-composite for supercapacitor

    Energy Technology Data Exchange (ETDEWEB)

    Yu, S.P.; Chang, X.C.; Wang, Z.M.; Han, K.F.; Zhu, H. [Beijing Univ. of Chemical Technology, Beijing (China). School of Science

    2010-07-01

    Supercapacitors combine the advantages of traditional capacitors and batteries. In this study, a zinc oxide (ZnO-PANI) nano-composite material was fabricated in order to investigate its behaviour in a supercapacitor application. The ZnO nano-powder was synthesized using the sol-gel method. An inverted emulsion polymerization method was then used to prepare the ZnO/PANI nanocomposite. X-ray diffraction (XRD) analyses demonstrated that the prepared ZnO had a hexagonal structure. The ZnO/PANI composite electrode was prepared. Electrochemical impedance spectroscopy (EIS) analyses indicated that the nano-composite material functioned well as an electrode. The highest capacitance rating achieved by the electrode was 31.82 F per g. 6 refs., 4 figs.

  18. Preparative isolation by high performance liquid chromatography of human insulin B chain produced in escherichia coli

    Energy Technology Data Exchange (ETDEWEB)

    Cruz, N.; Antonio, S.; De Anda, R.; Gosset, G.; Bolivar, F. (Centro de Investigacion sobre Ingenieria Genetica y Biotecnologia, Universidad Nacional Autonoma de Mexico, Apdo. Postal 510-3 Cuernavaca, Mor. 62271 (MX))

    1990-01-01

    This paper reports on a simple method developed for the analytical and preparative purification of human insulin B chain from recombinant origin. Three solvent systems: acetonitrile, isopropanol and methanol, were studied to determine their capacity to resolve the insulin B chain from a mixture of cyanogen bromide generated bacterial peptides. Using a {mu}Bondapak C18 column, it was possible to resolve the insulin B chain in all three systems. On a preparative scale, using a PrePak 500 C18 column with the isopropanol system, it was possible to purify insulin B chain and to obtain a 95% protein recovery.

  19. Preparation and characterization of high performance Schiff-base liquid crystal diepoxide polymer

    Energy Technology Data Exchange (ETDEWEB)

    Liu Huan; Fu Zien [Key Laboratory of Organic Polymer Material for Electronics, Guangzhou Institute of Chemistry, Chinese Academy of Sciences, P.O. BOX 1122, Guangzhou 510650 (China); Graduate School of the Chinese Academy of Sciences, Beijing 100049 (China); Xu Kai, E-mail: xk@gic.ac.cn [Key Laboratory of Organic Polymer Material for Electronics, Guangzhou Institute of Chemistry, Chinese Academy of Sciences, P.O. BOX 1122, Guangzhou 510650 (China); Cai Hualun; Liu Xin [Key Laboratory of Organic Polymer Material for Electronics, Guangzhou Institute of Chemistry, Chinese Academy of Sciences, P.O. BOX 1122, Guangzhou 510650 (China); Graduate School of the Chinese Academy of Sciences, Beijing 100049 (China); Chen Mingcai [Key Laboratory of Organic Polymer Material for Electronics, Guangzhou Institute of Chemistry, Chinese Academy of Sciences, P.O. BOX 1122, Guangzhou 510650 (China)

    2012-02-15

    Graphical abstract: The specific effects of highly conjugated Schiff-base moiety on thermal properties of the Schiff-base epoxy polymer were proposed first by us. From the point of view of structure-properties relationship, it can be considered that owing to the presence of the Schiff-base group, the high performance liquid crystal diepoxide polymer displayed improved thermal stability. Highlights: Black-Right-Pointing-Pointer In this work, we first proposed that specific effects of highly conjugated Schiff-base moiety on thermal properties of the Schiff-base epoxy polymer. Black-Right-Pointing-Pointer As one aim of this study, the thermal and thermal-oxidative stabilities of the thermosets were studied by TGA under nitrogen and under air. Black-Right-Pointing-Pointer The second aim of this study was to further understand the thermal degradation mechanism. Black-Right-Pointing-Pointer For thermal degradation mechanism of this polymer under nitrogen, TG-IR was used to investigate volatile components, and SEM/EDS was used to explore morphologies and chemical components of the residual char. Black-Right-Pointing-Pointer From the point of view of structure-properties relationship, it can be considered that owing to the presence of the Schiff-base group, the high performance liquid crystal diepoxide polymer displayed the improved thermal stability. - Abstract: A novel Schiff-base liquid crystal diepoxide polymer was prepared via a thermal copolymerization of a Schiff-base epoxy monomer (PBMBA) with a diamine co-monomer (MDA). We first proposed that specific effects of highly conjugated Schiff-base moiety on thermal properties of the Schiff-base epoxy polymer (PBMBA/MDA). Thermal degradation behavior of the polymer was characterized using thermogravimetric analysis (TGA) under nitrogen and under air, respectively. Thermogravimetric data obtained from TGA under nitrogen and under air reveal that PBMBA/MDA exhibits higher thermal stability compared with bisphenol-A type

  20. PREPARATION OF POLYETHERSULFONE ULTRAFILTRATION MEMBRANES FOR MILK CONCENTRATION AND EFFECTS OF ADDITIVES ON THEIR MORPHOLOGY AND PERFORMANCE

    Institute of Scientific and Technical Information of China (English)

    S.S. Madaeni; A. Rahimpour

    2005-01-01

    Polyethersulfone membranes were prepared from quaternary systems containing N,N-dimethylacetamide (DMAc) as solvent, polyvinylpyrrolidone (PVP) as constant additive and acetic acid, acetone and water as variable additives. Phase inversion via immersion precipitation was employed for manufacturing of membranes. The prepared films were immersed in the mixture of pure water and 2-propanol (30/70 vol%) as the non-solvent. Acetic acid caused an increment in the flux at high polymer concentration (16wt%) and a decline in the flux at low polymer concentrations (10 wt% and 13 wt%). Acetone and water as the solvent in the casting solution declined the flux at any polymer concentration tested. The morphology and performance of the prepared membranes were investigated by scanning electron microscopy and separation experiments using milk as the feed.

  1. Detection of Sulfur-Fumigated Paeoniae Alba Radix in Complex Preparations by High Performance Liquid Chromatography Tandem Mass Spectrometry

    Directory of Open Access Journals (Sweden)

    Song-Lin Li

    2012-07-01

    Full Text Available Detection of sulfur-fumigated Paeoniae Alba Radix (PAR in different complex preparations is challenging due to the relatively lower content of PAR and interference from more complicated components in complex preparations with different multiple constituent herbs. In this study, a high performance liquid chromatography- triple-quadrupole tandem mass spectrometry method was developed for detecting sulfur-fumigated PAR in different complex preparations. Paeoniflorin, the major component of PAR, and paeoniflorin sulfonate, the characteristic artifact transformed from paeoniflorin during sulfur-fumigation of PAR, were used as chemical markers. Multiple reaction monitoring (MRM scan was employed to maximize sensitivity and selectivity. Through optimizing full mass scan and daughter ion scan conditions, two mass transitions were selected and employed respectively for unequivocal identification of paeoniflorin and paeoniflorin sulfonate. The detection limits for paeoniflorin and paeoniflorin sulfonate using MRM were much lower than those detected with UV 270 nm. Paeoniflorin and paeoniflorin sulfonate could be simultaneously detected in different commercial PAR-containing complex preparations without interference of other components using the established method, indicating that the newly established method was selective and sensitive enough for screening sulfur-fumigated PAR in commercial complex preparations.

  2. High Performance Protein-Coated Microcrystals of Rhizomucor miehei Lipase: Preparation and Application for Organic Synthesis.

    Science.gov (United States)

    Kazlauskas, Simas; Kiriliauskaitė, Vita; Kalėdienė, Lilija; Bendikienė, Vida

    2015-05-01

    The goal of obtaining enzyme forms with higher catalytic activity, greater stability, and improved reusability has been pursued for the last few decades. Various novel biocatalyst designs have been created, and protein-coated microcrystals (PCMCs) are one of them. PCMC is an enzyme immobilization method based on simultaneous precipitation of protein and carrier, forming micron-sized enzyme-coated crystals. Highly active Rhizomucor miehei lipase (RML) PCMCs were prepared by immobilizing the protein onto K2SO4 as a carrier salt in acetone as a precipitating solvent. The formation of RML PCMCs was confirmed by scanning electron microscopy. Preparation of RML PCMCs was optimized by response surface methodology (RSM). Obtained PCMCs were found to be more active and stable during p-nitrophenyl palmitate hydrolysis in n-hexane, compared to liquid RML. The enzymatic activity and temperature optimum increased from 0.011 U/mg(soluble) lipase to 8.70 U/mg(immobilized) lipase and from 30 to 37 °C, respectively. Additionally, the ability of RML PCMCs to catalyze flavor ester 2-phenethyl octanoate synthesis was investigated. Some reaction parameters were optimized, resulting in 80 % conversion within 1 h with an enhanced reusability, compared to commercial immobilized RML preparation. Thus, PCMCs offer a cheap and effective technology for obtaining highly active lipase preparations for biocatalysis in organic media.

  3. School Leadership Preparation and Development in Kenya: Evaluating Performance Impact and Return on Leadership Development Investment

    Science.gov (United States)

    Asuga, Gladys; Eacott, Scott; Scevak, Jill

    2015-01-01

    Purpose: The purpose of this paper is to evaluate the quality of the current provision for school leadership in Kenya, the extent to which they have an impact on student outcomes and the return on school leadership preparation and development investment. Design/Methodology/Approach: The paper draws from educational leadership, management and…

  4. IELTS Preparation Course and Student IELTS Performance: A Case Study in Hong Kong

    Science.gov (United States)

    Zhengdong, Gan

    2009-01-01

    Since the University Grants Committee (UGC) selected the academic module of the International English Language Testing System (IELTS) as the common English proficiency assessment for graduating undergraduate degree students in 2002, almost all the tertiary institutions in Hong Kong have offered IELTS preparation courses that aim at providing…

  5. Study on preparation and application performance of blue sky rare earth light storage and emission material

    Institute of Scientific and Technical Information of China (English)

    ZHOU; Shao-hui; NI; Hai-yong; HUANG; Zhao-hui; LI; Xu-bo; DING; Jian-hong; ZHANG; Zhen

    2005-01-01

    Under reduction atmosphere, a blue sky rare earth silicate light storage and emission material was prepared by high temperature solid phase synthesis. The best constituent ratio of this material was determined through orthogonal experiment, and its excitation and emission spectra and X-ray diffraction patterns were measured. And a comparative study was conducted on its application properties.

  6. The Correlates of Academic Performance for English Language Learner Students in a New England District. Stated Briefly. REL 2014-021

    Science.gov (United States)

    Parker, Caroline E.; O'Dwyer, Laura M.; Irwin, Clare W.

    2014-01-01

    This "Stated Briefly" report is a companion piece that summarizes the results of another report of the same name. The study examined student and program characteristics that are related to English proficiency and content area achievement for English language learner (ELL) students in one urban district in Connecticut. Study authors found…

  7. The Correlates of Academic Performance for English Language Learner Students in a New England District. Stated Briefly. REL 2014-021

    Science.gov (United States)

    Parker, Caroline E.; O'Dwyer, Laura M.; Irwin, Clare W.

    2014-01-01

    This "Stated Briefly" report is a companion piece that summarizes the results of another report of the same name. The study examined student and program characteristics that are related to English proficiency and content area achievement for English language learner students in one urban district in New England. The study found that…

  8. Private Water Districts

    Data.gov (United States)

    California Department of Resources — Private Water District boundaries are areas where private contracts provide water to the district in California. This database is designed as a regions polygon...

  9. California Political Districts

    Data.gov (United States)

    California Department of Resources — This is a series of district layers pertaining to California'spolitical districts, that are derived from the California State Senateand State Assembly information....

  10. R9 Air Districts

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Region 9 Air Districts layer is a compilation of polygons representing the California Air Pollution Control and Air Quality Management Districts, Arizona Air...

  11. State Water Districts

    Data.gov (United States)

    California Department of Resources — State Water Project District boundaries are areas where state contracts provide water to the district in California. This database is designed as a regions polygon...

  12. National Register Historic Districts

    Data.gov (United States)

    Iowa State University GIS Support and Research Facility — The National Register Historic District layer is a shape file showing the boundaries of Historic Districts that are listed on the National Register of Historic Places.

  13. Legislative Districts - 1990

    Data.gov (United States)

    Kansas Data Access and Support Center — Each coverage contains a COVER-ID field that defines the House or Senate district number. Kansas House and Senate districts were created by the Legislative Research...

  14. Lieutenant Chief Warden Districts

    Data.gov (United States)

    Vermont Center for Geographic Information — This dataset is a representation overlay of Lieutenant Chief Warden Districts (areas of responsibility). The Vermont Lieutenant Chief Warden Districts layer is part...

  15. A hierarchical porous carbon membrane from polyacrylonitrile/polyvinylpyrrolidone blending membranes:Preparation, characterization and electrochemical capacitive performance

    Institute of Scientific and Technical Information of China (English)

    Huili Fan; Fen Ran∗; Xuanxuan Zhang; Haiming Song; Wenxia Jing; Kuiwen Shen; Lingbin Kong; Long Kang

    2014-01-01

    Novel hierarchical porous carbon membranes were fabricated through a simple carbonization procedure of well-defined blending polymer membrane precursors containing the source of carbon polyacrylonitrile (PAN) and an additive of polyvinylpyrrolidone (PVP), which was prepared using phase inversion method. The as-fabricated materials were further used as the active electrode materials for supercapacitors. The effects of PVP concentration in the casting solution on structure feature and electrochemical capacitive performance of the as-prepared carbon membranes were also studied in detail. As the electrode material for supercapacitor, a high specific capacitance of 278.0 F/g could be attained at a current of 5 mA/cm2 and about 92.90%capacity retention could be maintained after 2000 charge/discharge cycles in 2 mol/L KOH solution with a PVP concentration of 0.3 wt%in the casting solution. The facile hierarchical pore structure preparation method and the good electrochemical capacitive performance make the prepared carbon membrane particularly promising for use in supercapacitor.

  16. Simultaneously preparative purification of Huperzine A and Huperzine B from Huperzia serrata by macroporous resin and preparative high performance liquid chromatography.

    Science.gov (United States)

    Zhang, Hongchao; Liang, Hao; Kuang, Pengqun; Yuan, Qipeng; Wang, Yan

    2012-09-01

    Huperzine A (HupA) and Huperzine B (HupB) are natural alkaloids existed in Lycopodium plants. They both have potential clinical application for treating Alzheimer's Disease (AD). For the purpose of better utilizing the limited plant resources, a quick and low cost method to separate and purify HupA and HupB from Huperzia serrata (Thunb. ex Murray) was established in this paper. Low polarity macroporous resin SP850 was selected from eight kinds of resins during initial purification. Trifluoroacetic acid (TFA) was proved to be the best acid modifier reagent among all acids used in our experiment for improving separation. HupA and HupB were baseline separated on a C18 column by preparative high performance liquid chromatography (Preparative HPLC), the optimal gradient mobile phase system contained methanol increasing from 15% (v/v) to 35% (v/v) and 0.1% (v/v) TFA within the water. The purity of HupA and HupB obtained was 99.1% and 98.6%, respectively, and the total recovery for them was 83.0% and 81.8%, respectively.

  17. Electrochemical performance of nano-scale β-Ni(OH)2 prepared at different transformations of pH value

    Institute of Scientific and Technical Information of China (English)

    ZHAO Li; ZHANG Li-jun; HAN Xi-jiang; ZHANG Cui-fen

    2008-01-01

    The influence of transforming pH values on the electrochemical performance of nano-scale Ni(OH)2was analyzed. The measurement results of XRD indicate that the nano-scale Ni (OH)2 prepared at different transformations of pH value is β( Ⅱ )-phase with different crystal lattice parameters. Cyclic voltammograms (CV) and electrochemical impedance spectroscopy(EIS) measurement results show that transformations of pH value affect the proton diffusion coefficient (D) and charge-transfer resistance (Rct) of the material. The simu-lation of cell experiment shows that the sample prepared at a pH of 10. 1 exhibits the maximum specific capacity(327. 8 mAh/g) and higher discharge platform, the discharge performance of electrodes depends on both D and Rct, so the kinetics characteristics that electrodes reaction is controlled by both mass-transfer step and charge-transfer step are put forward.

  18. District nursing in Dominica

    NARCIS (Netherlands)

    Kolkman, PME; Luteijn, AJ; Nasiiro, RS; Bruney, [No Value; Smith, RJA; Meyboom-de Jong, B

    1998-01-01

    District nurses constitute the basis of the primary health care services in Dominica. All encounters of three district nurses were registered using the international classification of primary care. Information on other aspects of district nursing was collected by participating observation and the us

  19. District nurse training

    OpenAIRE

    Elliott, Arnold; Freeling, Paul; Owen, John

    1980-01-01

    Training for district nursing is being reviewed. By 1981 district nurses will have a new administrative structure, a new curriculum, and a new examination. Training for nursing, like that for general practice, is to become mandatory. The history of the development of district nurse training is briefly described.

  20. District nursing in Dominica

    NARCIS (Netherlands)

    Kolkman, PME; Luteijn, AJ; Nasiiro, RS; Bruney, [No Value; Smith, RJA; Meyboom-de Jong, B

    1998-01-01

    District nurses constitute the basis of the primary health care services in Dominica. All encounters of three district nurses were registered using the international classification of primary care. Information on other aspects of district nursing was collected by participating observation and the

  1. Preparation of Al-doped ZnO nanocrystalline aggregates with enhanced performance for dye adsorption

    Science.gov (United States)

    Zhang, Jin; Que, WenXiu; Yuan, Yuan; Zhong, Peng; Liao, YuLong

    2012-07-01

    Al-doped ZnO (AZO) nanocrystalline aggregates (NCAs) were prepared by a low cost colloid chemistry method and effects of the Al-doped concentration on the morphological and structural properties of the AZO NCAs were studied. The dye adsorption ability of the AZO NCAs with various Al-doped concentrations was also investigated. Results indicate that the doping of the Al ions not only does not change the wurtzite structure of the ZnO crystal but also can reduce the crystallite grain size and the particle size distribution of the NCAs, which gives them a higher specific surface area and dye adsorption ability than that of the ZnO NCAs. The as-prepared AZO NCAs would be a promising material to be applied in the dye sensitized solar cells and water treatment.

  2. Preparation and Performance Analysis of Inorganic Polymer Flocculant PZFSiC

    Institute of Scientific and Technical Information of China (English)

    GAN Li; MENG Zhao-ping; Pan Jie-nan

    2004-01-01

    A new inorganic polymer flocculant-PZFSiC (zinc-iron-silicate polymer composite) is prepared by adding acid into a high modulus solution of water glass and introducing appropriate metallic ions(M) including Zn and Fe. The influence on flocculability of factors such as the mole ratios of M to SiO2,stirring time and pH are discussed .And the optimal preparing technical parameters are obtained by orthogonal tests. The optimum technical conditions of flocculation are determined. The result shows that when less PZFSiC is added into troubled water or waste water, turbidity removal can hit 98%, COD removal can exceed 93%. The water sample treated is clear and of good quality. These results also indicate that PZFSiC is a highly effective, nontoxic and benign to the enviroment.

  3. Preparation and adsorption performances of mesopore-enriched bamboo activated carbon

    Institute of Scientific and Technical Information of China (English)

    Yuxin WANG; Congmin LIU; Yaping ZHOU

    2008-01-01

    Activated carbon with high specific surface area and considerable mesopores was prepared from bam-boo scraps by phosphoric acid activation. The effect of activation conditions was studied. Under the conditions of impregnating bamboo with 80% H3PO4 at 80℃ for 9 days and activation at 500℃ for 4 h, the prepared acti-vated carbon had the highest mesopore volume of 0.67 cm3/g, a specific surface area of 1567 m2/g, and the mesopore ratio reached 47.18%. The study on adsorption isotherms of CH4, CO2, N2 and O2on the activated carbon were carried out at 298 K. The considerable difference in the adsorption capacity between CO2 and the other gases was observed, which would be of interest for the adsorp-tive separation/purification of gaseous CO2 from its mix-tures, especially from mixtures with N2 and/or O2.

  4. Study of the Preparation, Characterization, and Sizing Performance of Modified Collagen Surface Sizing Agent

    Directory of Open Access Journals (Sweden)

    Xuechuan Wang

    2014-01-01

    Full Text Available In this work, a surface sizing agent for paper was prepared by the emulsion polymerization method, in which the collagen extracted from leather shavings was modified. The product was characterized using Fourier Transform-Infrared Spectroscopy (FT-IR, Transmission Electron Microscopy (TEM, X-ray Diffraction (XRD, Energy Dispersive X-ray detector (EDX, and atomic absorption spectrophotometry. Corrugated papers were used as models. The synergy between modified collagen sizing emulsion and two commercial synthetic sizing agents was studied. Finally, the morphology of the papers before and after being treated was observed by Scanning Electron Microscopy (SEM. The results indicated that the sizing agent could be prepared using collagen as a raw material, which not only can alleviate a pollution problem in the leather industry, but also provide a novel alternative sizing agent for the paper industry, providing considerable economic, social, and environmental benefits to both industries.

  5. Isolation of lignans glycosides from Alibertia sessilis (Vell.) K. Schum. (Rubiaceae) by preparative high-performance liquid chromatography

    Energy Technology Data Exchange (ETDEWEB)

    Silva, V.C. da; Bolzani, V. da S.; Lopes, M.N. [UNESP, Araraquara, SP (Brazil). Inst. de Quimica. Dept. de Quimica Organica; Silva, G.H. [Universidade Federal de Sergipe, Aracaju, SE (Brazil). Dept. de Quimica]. E-mail: mnlopes@iq.unesp.br

    2006-10-15

    Enantiomeric aglycone lignans contained in a mixture were separated from a fraction of the extract of the stems of Alibertia sessilis (Vell.) K. Schum. (Rubiaceae) by preparative high-performance liquid chromatography. An efficient and fast separation can be achieved with methanol-water (30:70, v/v). Their structures were identified as (+)-lyoniresinol 3{alpha}-O-{beta}-glucopyranoside and (-)-lyoniresinol 3{alpha}-O-{beta}-glucopyranoside, being reported for the first time in Rubiaceae. (author)

  6. Efficacy of Video-Assisted Instruction on Knowledge and Performance of Dental Students in Access Cavity Preparation

    OpenAIRE

    Naseri, Mandana; Shantiaee, Yazdan; Rasekhi, Javid; Zadsirjan, Saeede; Mojtahed Bidabadi, Maryam; Khayat, Akbar

    2016-01-01

    Introduction: The conventional method of teaching endodontics has some drawbacks. Due to the small size of the oral cavity, students cannot closely observe the clinical procedure. Use of new teaching modalities such as the intraoral camera may obviate this problem. This study assessed the effect of video-assisted clinical instruction in dentistry (VACID) on dental student’s knowledge and performance in access cavity preparation during endodontic treatment. Methods and Materials: In this inter...

  7. [Preparation, characterization and adsorption performance of mesoporous activated carbon with acidic groups].

    Science.gov (United States)

    Li, Kun-Quan; Li, Ye; Zheng, Zheng; Zhang, Yu-Xuan

    2013-06-01

    Mesoporous activated carbons containing acidic groups were prepared with cotton stalk based fiber as raw materials and H3PO4 as activating agent by one step carbonization method. Effects of impregnation ratio, carbonization temperature and heat preservation time on the yield, elemental composition, oxygen-containing acid functional groups and adsorptive capacity of activated carbon were studied. The adsorption capacity of the prepared activated carbon AC-01 for p-nitroaniline and Pb(II) was studied, and the adsorption mechanism was also suggested according to the equilibrium experimental results. The maximum yield of activated carbons prepared from cotton stalk fiber reached 35.5% when the maximum mesoporous volume and BET surface area were 1.39 cm3 x g(-1) and 1 731 m2 x g(-1), respectively. The activated carbon AC-01 prepared under a H3 PO4/precursor ratio of 3:2 and activated at 900 degrees C for 90 min had a total pore volume of 1.02 cm3 x g(-1), a micoporous ratio of 31%, and a mesoporous ratio of 65%. The pore diameter of the mesoporous activated carbon was mainly distributed in the range of 2-5 nm. The Langmuir maximum adsorption capacities of Pb(II) and p-nitroaniline on cotton stalk fiber activated carbon were 123 mg x g(-1) and 427 mg x g(-1), respectively, which were both higher than those for commercial activated carbon fiber ACF-CK. The equilibrium adsorption experimental data showed that mesopore and oxygen-containing acid functional groups played an important role in the adsorption.

  8. Differences in torsional performance of single- and multiple-instrument rotary systems for glide path preparation.

    Science.gov (United States)

    Arias, Ana; Singh, Rupinderpal; Peters, Ove A

    2016-05-01

    A new rotary instrument has been developed to simplify the glide path preparation in root canals before shaping procedures. The purpose of this study was to compare the peak torque and force induced by nickel-titanium PathFile multiple-instrument system and the recently developed M-Wire ProGlider single instrument during glide path preparation of mesial root canals in extracted mandibular molars. Each independent canal of eight mesial roots of mandibular molars was randomly assigned to achieve a reproducible glide path with a new set of either PathFile #1 and #2 or ProGlider after negotiation with a 10 K-file. Tests were run in a standardized fashion using a torque-testing platform. Peak torque (N cm) and force (N) were registered and analysis of variance and Tukey post-hoc tests were applied. Preliminary data for stationary torque at failure were also obtained and compared with peak torque for each instrument. PathFile #1 and #2 instruments showed statistically lower peak torque (p = 0.001) and peak force (p = 0.008) than ProGlider. Torque at failure according to ADA No. 28/ISO 36030-1 was not significantly different from peak torque during glide path preparation for ProGlider instruments while it was significantly higher for PathFile #1 and #2 (p path preparation compared to ProGlider, which is possibly subjected to a greater contact with the canal walls due to the increase in its flute diameter at middle and coronal levels.

  9. Preparation of hierarchical porous Zn-salt particles and their superhydrophobic performance

    Energy Technology Data Exchange (ETDEWEB)

    Gao, Dahai; Jia, Mengqiu, E-mail: jiamq@mail.buct.edu.cn

    2015-12-30

    Graphical abstract: - Highlights: • Hierarchical particles with high roughness were prepared by modified hydrothermal route. • The high roughness is provided by extremely low thickness of sheet crystals. • FEVE polymer derivative was used for surface treatment of hierarchical surface. • The novel particles via surface treatment were firstly used as superhydrophobic materials. • The product properties were compared with multi-scale ZnO particles via conventional route. - Abstract: Superhydrophobic surfaces arranged by hierarchical porous particles were prepared using modified hydrothermal routes under the effect of sodium citrate. Two particle samples were generated in the medium of hexamethylenetetramine (P1) and urea (P2), respectively. X-ray diffraction, scanning electron microscope, and transmission electron microscope were adopted for the investigation, and results revealed that the P1 and P2 particles are porous microspheres with crosslinked extremely thin (10–30 nm) sheet crystals composed of Zn{sub 5}(OH){sub 8}Ac{sub 2}·2H{sub 2}O and Zn{sub 5}(CO{sub 3}){sub 2}(OH){sub 6}, respectively. The prepared particles were treated with a fluoroethylene vinyl ether derivative and studied using Fourier transform infrared spectroscopy and energy-dispersive X-ray spectrometer. Results showed that the hierarchical surfaces of these particles were combined with low-wettable fluorocarbon layers. Moreover, the fabricated surface composed of the prepared hierarchical particles displayed considerably high contact angles, indicating great superhydrophobicity for the products. The wetting behavior of the particles was analyzed with a theoretical wetting model in comparison with that of chestnut-like ZnO products obtained through a conventional hydrothermal route. Correspondingly, this study provided evidence that high roughness surface plays a great role in superhydrophobic behavior.

  10. Preparation and Antiflame Performance of Expandable Graphite Modified with Sodium Hexametaphosphate

    Directory of Open Access Journals (Sweden)

    Hongmei Zhao

    2015-01-01

    Full Text Available A kind of polyphosphate modified expandable graphite (EGp was prepared in graphite oxidation and intercalation reaction with KMnO4 as oxidant, H2SO4 as intercalator, and sodium hexametaphosphate (SHMP as assistant intercalator. The feasible mass ratio of C : KMnO4 : H2SO4 (98% : SHMP was determined as 1.0 : 0.3 : 4.5 : 0.6, H2SO4 was diluted to 77 wt% before intercalation reaction, and the reaction lasted for 40 min at 40°C. Expanded volume and initial expansion temperature of the prepared EGp reached 600 mL/g (at 800°C and 151°C, respectively. X-ray diffraction spectroscopy testified the intercalation and layer structure of EGp, and Fourier transform infrared spectroscopy illuminated the intercalated functional groups. Flame retardance of the prepared EGp and the referenced EG (with only H2SO4 as intercalator for linear low density polyethylene (LLDPE was also investigated. Addition of 30 wt% EGp to the polymer improved the limiting oxygen index (LOI from 17.5 to 27.3%. On the other hand, the LOI of the same amount of the referenced EG was only 24.6%. Assistant intercalation of SHMP improved the dilatability and flame retardancy.

  11. Preparation of hierarchical porous Zn-salt particles and their superhydrophobic performance

    Science.gov (United States)

    Gao, Dahai; Jia, Mengqiu

    2015-12-01

    Superhydrophobic surfaces arranged by hierarchical porous particles were prepared using modified hydrothermal routes under the effect of sodium citrate. Two particle samples were generated in the medium of hexamethylenetetramine (P1) and urea (P2), respectively. X-ray diffraction, scanning electron microscope, and transmission electron microscope were adopted for the investigation, and results revealed that the P1 and P2 particles are porous microspheres with crosslinked extremely thin (10-30 nm) sheet crystals composed of Zn5(OH)8Ac2·2H2O and Zn5(CO3)2(OH)6, respectively. The prepared particles were treated with a fluoroethylene vinyl ether derivative and studied using Fourier transform infrared spectroscopy and energy-dispersive X-ray spectrometer. Results showed that the hierarchical surfaces of these particles were combined with low-wettable fluorocarbon layers. Moreover, the fabricated surface composed of the prepared hierarchical particles displayed considerably high contact angles, indicating great superhydrophobicity for the products. The wetting behavior of the particles was analyzed with a theoretical wetting model in comparison with that of chestnut-like ZnO products obtained through a conventional hydrothermal route. Correspondingly, this study provided evidence that high roughness surface plays a great role in superhydrophobic behavior.

  12. Connecting Asian Heritage Conservation to the Idea of Performative Regionalism: A Case of Community-Enhancing Design Interventions in the Historical Art District of Liulichang Beijing

    Directory of Open Access Journals (Sweden)

    Diana Thamrin

    2015-02-01

    Full Text Available The active and sometimes ruthless modernisation in Asia has triggered an urgent need to secure the protection and continuation of its rich heritage and diverse regional attributes. However, as in the case of China, the Asian perspective of conservation is different from the West in terms of the nature or ways of design interventions produced and its purposes. This phenomenon has frequently triggered criticisms from heritage conservation professionals. Hence, the objective of this paper is to explore the interventions done on Asian heritage sites, taking the Liulichang Art District in Beijing as the case study, and analyze the positive influence they have brought. The paper starts by distinguishing the Asian concept and values of authenticity in conservation that differ from the West and how these principles have been applied in Liulichang, a famous ancient street known for the selling and practice of classical Chinese arts, mostly for Chinese painting. Using the phenomenological method of analysis, the paper further elaborates on the importance of community building in learning and appreciating the art of Chinese painting and discusses the positive impact made by the design interventions in Liulichang, particularly in terms of community engagement and creation of novel ways to accommodate traditional cultural practices of Chinese painting. Results reflect that the Asian perspective of conservation do not always follow the principle of minimum intervention favoured by the West, but how contemporary interventions could be merged into the heritage site to revive regional communities and cultural activities, connecting Asian architectural conservation with the design approach coined by Barbara Allen (2005 as Performative Regionalism, hence developing the idea and practice of this approach as a result of the discussion. Rather than merely following textual or scientific procedures like in the West, this approach requires a more experiential way of

  13. Performance: A Strategy for Professional Development in Early Childhood Teacher Preparation

    Science.gov (United States)

    Maude, Susan P.; Brotherson, Mary Jane; Summers, Jean Ann; Erwin, Elizabeth J.; Palmer, Susan; Peck, Nancy F.; Zheng, Yu Zhu; Kruse, Aryn; Haines, Shana J.; Weigel, Cindy J.

    2011-01-01

    The purpose of this article is to propose performance as a creative instructional strategy to convey complex competencies related to understanding and working effectively with families in early childhood education. Performance derives from performance ethnography, which is a qualitative research methodology. Its application to professional…

  14. Influence of Preparation Conditions on the Catalytic Performance of MoNx/SBA-15 for Ammonia Decomposition

    Institute of Scientific and Technical Information of China (English)

    Hongchao Liu; Hua Wang; Jianghan Shen; Ying Sun; Zhongmin Liu

    2006-01-01

    The influence of preparation conditions (e.g. H2-N2 ratios, final nitriding temperatures) on the performance of MoNx/SBA-15 catalysts for ammonia decomposition was investigated. The variation of catalytic activity with H2-N2 ratios may be attributed to the variation of surface compositions and particle sizes of the active components. The variation of nitriding temperatures leads to the formation of molybdenum nitride domains of varying compositions, which are responsible for the difference in their catalytic performance with respect to ammonia decomposition. At 923 K, ammonia could be completely decomof ammonia.

  15. Using an Inducible Promoter of a Gene Encoding Penicillium verruculosum Glucoamylase for Production of Enzyme Preparations with Enhanced Cellulase Performance

    Science.gov (United States)

    Gusakov, Alexander V.; Nemashkalov, Vitaly A.; Satrutdinov, Aidar D.; Sinitsyn, Arkady P.

    2017-01-01

    Background Penicillium verruculosum is an efficient producer of highly active cellulase multienzyme system. One of the approaches for enhancing cellulase performance in hydrolysis of cellulosic substrates is to enrich the reaction system with β -glucosidase and/or accessory enzymes, such as lytic polysaccharide monooxygenases (LPMO) displaying a synergism with cellulases. Results Genes bglI, encoding β-glucosidase from Aspergillus niger (AnBGL), and eglIV, encoding LPMO (formerly endoglucanase IV) from Trichoderma reesei (TrLPMO), were cloned and expressed by P. verruculosum B1-537 strain under the control of the inducible gla1 gene promoter. Content of the heterologous AnBGL in the secreted multienzyme cocktails (hBGL1, hBGL2 and hBGL3) varied from 4 to 10% of the total protein, while the content of TrLPMO in the hLPMO sample was ~3%. The glucose yields in 48-h hydrolysis of Avicel and milled aspen wood by the hBGL1, hBGL2 and hBGL3 preparations increased by up to 99 and 80%, respectively, relative to control enzyme preparations without the heterologous AnBGL (at protein loading 5 mg/g substrate for all enzyme samples). The heterologous TrLPMO in the hLPMO preparation boosted the conversion of the lignocellulosic substrate by 10–43%; however, in hydrolysis of Avicel the hLPMO sample was less effective than the control preparations. The highest product yield in hydrolysis of aspen wood was obtained when the hBGL2 and hLPMO preparations were used at the ratio 1:1. Conclusions The enzyme preparations produced by recombinant P. verruculosum strains, expressing the heterologous AnBGL or TrLPMO under the control of the gla1 gene promoter in a starch-containing medium, proved to be more effective in hydrolysis of a lignocellulosic substrate than control enzyme preparations without the heterologous enzymes. The enzyme composition containing both AnBGL and TrLPMO demonstrated the highest performance in lignocellulose hydrolysis, providing a background for developing a

  16. Yolk-shelled cathode materials with extremely high electrochemical performances prepared by spray pyrolysis

    Science.gov (United States)

    Choi, Seung Ho; Hong, Young Jun; Kang, Yun Chan

    2013-08-01

    A facile, continuous preparation process of yolk-shell-structured lithium-metal oxide powders without a template for use as cathode materials in lithium ion batteries is introduced for the first time. Single and double-shelled LiNi0.5Mn1.5O4 yolk-shell powders as the first target materials are prepared directly by spray pyrolysis from a spray solution with sucrose, at a short residence time of 4 s. Fast combustion and contraction of a carbon-mixed oxide composite intermediate, formed from a micro-sized droplet inside a hot wall reactor maintained at 700 °C, produces the yolk-shell powders. The yolk-shell structure of the precursor powders directly prepared by spray pyrolysis is well maintained even at a high post-treatment temperature of 750 °C. The yolk-shell LiNi0.5Mn1.5O4 powders delivered a 1000th high discharge capacity of 108 mA h g-1 at 10 C. The discharge capacities are as high as 103, 95, and 91 mA h g-1 at extremely high discharge rates of 100, 200, and 300 C and the corresponding specific energy densities are 420, 370, and 328 W h kg-1. The capacity retention at a constant discharge rate of 200 C is 90% after 500 cycles.A facile, continuous preparation process of yolk-shell-structured lithium-metal oxide powders without a template for use as cathode materials in lithium ion batteries is introduced for the first time. Single and double-shelled LiNi0.5Mn1.5O4 yolk-shell powders as the first target materials are prepared directly by spray pyrolysis from a spray solution with sucrose, at a short residence time of 4 s. Fast combustion and contraction of a carbon-mixed oxide composite intermediate, formed from a micro-sized droplet inside a hot wall reactor maintained at 700 °C, produces the yolk-shell powders. The yolk-shell structure of the precursor powders directly prepared by spray pyrolysis is well maintained even at a high post-treatment temperature of 750 °C. The yolk-shell LiNi0.5Mn1.5O4 powders delivered a 1000th high discharge capacity of 108 m

  17. Preparation and Dyeing Performance of a Novel Crosslinking Polymeric Dye Containing Flavone Moiety

    Institute of Scientific and Technical Information of China (English)

    TANG Lijun; TANG Bingtao; ZHANG Shufen

    2011-01-01

    A yellow crosslinking polymeric dye was prepared by grafting the flavone moiety containing azo chromophore onto polyvinylamine backbone.The λ max of this polymeric dye in water is 382 nm.The polymeric dye is fixed to silk and cotton with a crosslinking agent,2-chloro-4,6-di(aminobenzene-4'-β-sulphatoethylsulphone)-1,3,5-s-triazine,which acts as a bridge between the fiber and dye molecules.The fixation of this polymeric dye reaches 99% and the dyed samples exhibit excellent rubbing and washing fastness.

  18. The effects of Te on the performance of Mo-V catalysts prepared by hydrothermal synthesis

    Institute of Scientific and Technical Information of China (English)

    Hua Chang Jiang; Ling Zeng; Bin Long Yin

    2007-01-01

    Some Mo-V-Te-La catalysts with varied component were prepared by hydrothermal synthesis and dried with microwave method. The component of the catalyst were greatly affected the crystal structure and Raman spectrum. The phase in the catalysts was different when the Mo, V, and Te content varied. When the catalyst containing the same Mo, V content, due to the effect of dopant of Te element (V0.07 Mo0.93)5O14 became the main phase in the catalyst. The catalyst also showed good activity for the reaction of selective oxidation propane to acrolein and acrylic acid.

  19. Preparation of high-performance optical coatings with fluoride nanoparticle films made from autoclaved sols.

    Science.gov (United States)

    Murata, Tsuyoshi; Ishizawa, Hitoshi; Motoyama, Izumi; Tanaka, Akira

    2006-03-01

    An ultralow refractive index is very advantageous when one designs antireflective coatings. We successfully obtained high-quality MgF2 thin films with ultralow refractive indices from autoclaved sols prepared from magnesium acetate and hydrofluoric acid. The MgF2 films consist of nanosized particles, and they have high laser-exposure durability at 193 nm. The reflectance of the antireflective coating with five layers, of which the top layer is formed by our method, is lower than 0.6% in the incident angle range of 0 degrees - 60 degrees at 193 nm.

  20. Study of prevalence of work related stress and co-morbidities and its effect on work performance in KSRTC workers of Dakshina Kannada district, Karnataka, India

    Directory of Open Access Journals (Sweden)

    Sudhir Prabhu

    2015-11-01

    Conclusions: Very few studies have been conducted to assess stress levels in organized sectors in India and Karnataka. Hence the present study was undertaken to assess the stress levels and associated health disorders amongst the KSRTC workers of Dakshina Kannada district and to suggest suitable measures to improve occupational health, if necessary. [Int J Res Med Sci 2015; 3(11.000: 3161-3166

  1. Cross-District Collaboration: Curriculum and Professional Development

    Science.gov (United States)

    Short, Deborah J.; Cloud, Nancy; Morris, Patricia; Motta, Julie

    2012-01-01

    Secondary English as a second language (ESL) curricula that address four levels of ESL proficiency and prepare students for the English language arts (ELA) curricula and state-mandated ELA tests are not common. A curriculum jointly developed by two districts is even rarer. Yet two urban districts in Rhode Island undertook such a curriculum…

  2. Sustaining Community Partnership across Transition in District Leadership

    Science.gov (United States)

    LeChasseur, Kimberly

    2017-01-01

    This case of district turnover was developed as part of a project with state leaders and funders supporting local early education systems development. Understanding strategic and reactive activities during district leadership transition can be useful in assisting educators and their partners to prepare for sustainability. In this case, early…

  3. Cross-District Collaboration: Curriculum and Professional Development

    Science.gov (United States)

    Short, Deborah J.; Cloud, Nancy; Morris, Patricia; Motta, Julie

    2012-01-01

    Secondary English as a second language (ESL) curricula that address four levels of ESL proficiency and prepare students for the English language arts (ELA) curricula and state-mandated ELA tests are not common. A curriculum jointly developed by two districts is even rarer. Yet two urban districts in Rhode Island undertook such a curriculum…

  4. Mathematical models of hydrocyclone performance in various copper ores preparation circuits

    Directory of Open Access Journals (Sweden)

    Niedoba Tomasz

    2016-01-01

    Full Text Available Copper ores located in the Lubin-Glogow Copper Basin contain three main lithological fractions: sandstone, carbonate and shale. This fact is the basic problem of organization and conducting ore preparation to flotation. The existing circuit of feed preparation contains (in ZG Rudna five classification nodes of hydrocyclones which fit for various purposes. The elaboration of concept of monitoring work of these nodes should be based on appropriate mathematical models of process. It was decided that either regressive or non-dimensional models that is classification according to Svarovsky, and particularly Plitt’s, will be suitable, in the aspects of d50 and partition sharpness. Errors resulting from determination of the features being part of the equations were also important. In this paper the errors were divided into technical and technological. The issue of experiments organization (mineralogical investigation connected with each classification node was also addressed. It is obvious that each classification node must obtain its characteristics because of various comminution products directed to classification.

  5. Performance Evaluation of Fast Microfluidic Thermal Lysis of Bacteria for Diagnostic Sample Preparation

    Directory of Open Access Journals (Sweden)

    Evangelyn C. Alocilja

    2013-01-01

    Full Text Available Development of new diagnostic platforms that incorporate lab-on-a-chip technologies for portable assays is driving the need for rapid, simple, low cost methods to prepare samples for downstream processing or detection. An important component of the sample preparation process is cell lysis. In this work, a simple microfluidic thermal lysis device is used to quickly release intracellular nucleic acids and proteins without the need for additional reagents or beads used in traditional chemical or mechanical methods (e.g., chaotropic salts or bead beating. On-chip lysis is demonstrated in a multi-turn serpentine microchannel with external temperature control via an attached resistive heater. Lysis was confirmed for Escherichia coli by fluorescent viability assay, release of ATP measured with bioluminescent assay, release of DNA measured by fluorometry and qPCR, as well as bacterial culture. Results comparable to standard lysis techniques were achievable at temperatures greater than 65 °C and heating durations between 1 and 60 s.

  6. Preparation of ultrafine Ce-based oxide nanoparticles and their catalytic performances for diesel soot combustion

    Institute of Scientific and Technical Information of China (English)

    韦岳长; 赵震; 焦金庆; 刘坚; 段爱军; 姜桂元

    2014-01-01

    The ultrafine Ce-based oxide nanoparticles with different element dopings (Zr, Y) were synthesized by the method of mi-cropores-diffused coprecipitation (MDC) using ammonia solution as the precipitation agent. The activities of the catalysts for soot oxidation were evaluated by the temperature-programmed oxidation (TPO) reaction. Ce-based oxides prepared in this study exhibited high catalytic activity for soot oxidation under the condition of loose contact between soot particles and catalysts, and the catalytic ac-tivity of ultrafine Ce0.9Zr0.1O2 nanoparticle for soot combustion was the highest, whose T10, T50 and SCO2m was 364, 442 ºC and 98.3%, respectively. All catalysts were systematically characterized by means of X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Brumauer-Emett-Teller (BET), Fourier transform infrared spectroscopy (FT-IR) and UV-Vis diffuse reflectance spectroscopy (UV-Vis DRS). It was indicated that the MDC method could prepare the ultrafine Ce-based oxide nanoparticles whose the crystal lattice were perfect, and the BET surface area and average crystal size of the ultrafine nanoparticles changed with the different element dopings (Zr, Y). The H2-TPR measurements showed that the ultrafine Ce-based ox-ide nanoparticles with the doping-Zr cation could be favorable for improving the redox property of the catalysts.

  7. High performance liquid chromatographic determination of some guaiphenesin-containing cough-cold preparations

    Directory of Open Access Journals (Sweden)

    Mohamed A. Korany

    2011-04-01

    Full Text Available This paper presents different HPLC methods for the simultaneous determination of some guaiphenesin-containing cough-cold preparations. Three pharmaceutically available combinations were analyzed: salbutamol sulfate (SAL and guaiphenesin (GUA, combination I; ascorbic acid (ASC, paracetamol (PAR and guaiphenesin (GUA, combination II; and theophylline anhydrous (THE, guaiphenesin (GUA and ambroxol hydrochloride (AMB, combination III. A 250 × 4.6 mm C-18 column was used for all combinations. The mobile phase for the three combinations consisted of a mixture of methanol and 0.01 M aqueous phosphate buffer solution. The pH of the mobile phase was adjusted to 3.2, 6.2 and 3.8 for combinations I, II and III, respectively. The proposed HPLC methods were successfully applied to the determination of the investigated drugs, both in synthetic mixtures and in pharmaceutical preparations, without any matrix interference and with high precision and accuracy. Different aspects of analytical validation are presented in the text.

  8. Novel preparation of highly dispersed Ni2P embedded in carbon framework and its improved catalytic performance

    Science.gov (United States)

    Wang, Shan; Wang, Kang; Wang, Xitao

    2016-11-01

    Highly dispersed Ni2P embedded in carbon framework with different phosphidation temperature was prepared through carbonizing Ni-alginate gel and followed by phosphidation with PPh3 in liquid phase. The significant effects of phosphidation temperature on Ni2P particle size and catalytic properties for isobutane dehydrogenation to isobutene were investigated. The results showed that Ni2P catalyst derived from the Ni-alginate gel (Ni2P-ADC), consisting of Ni2P particles embedded in carbon walls, possessed smaller particle size and more active site compared with Ni2P catalyst supported on active carbon (Ni2P/AC) prepared by impregnation method. The Ni2P-ADC catalyst phosphorized at 578 K for 3 h exhibited the highest catalytic performance, with the corresponding selectivity of isobutene approaching 89% and conversion approaching 15% after reaction for 4.5 h at 833 K, whereas Ni2P/AC catalyst prepared by impregnation method displays a much lower catalytic activity. The improved catalytic performance of the Ni2P-ADC can be ascribed to the smaller and highly dispersed Ni2P particles incorporated into carbon framework resulting from Ni-alginate gel.

  9. Isolation and purification of diastereoisomeric flavonolignans from silymarin by binary-column recycling preparative high-performance liquid chromatography.

    Science.gov (United States)

    Zhao, Weiquan; Yang, Guang; Zhong, Fanyi; Yang, Nan; Zhao, Xin; Qi, Yunpeng; Fan, Guorong

    2014-09-01

    Silymarin extracted from Silybum marianum (L.) Gaertn consists of a large number of flavonolignans, of which diastereoisomeric flavonolignans including silybin A and silybin B, and isosilybin A and isosilybin B are the main bioactive components, whose preparation from the crude extracts is still a difficult task. In this work, binary-column recycling preparative high-performance liquid chromatography systems without sample loop trapping, where two columns were switched alternately via one or two six-port switching valves, were established and successfully applied to the isolation and purification of the four diastereoisomeric flavonolignans from silymarin. The proposed system showed significant advantages over conventional preparative high-performance liquid chromatography with a single column in increasing efficiency and reducing the cost. To obtain the same amounts of products, the proposed system spends only one tenth of the time that the conventional system spends, and needs only one eleventh of the solvent that the conventional system consumes. Using the proposed system, the four diastereoisomers were successfully isolated from silymarin with purities over 98%.

  10. Stoichiometry-controlled high-performance LiCoO 2 electrode materials prepared by a spray solution technique

    Science.gov (United States)

    Konstantinov, K.; Wang, G. X.; Yao, J.; Liu, H. K.; Dou, S. X.

    LiCoO 2 cathode materials have been prepared by a spray-drying technique. The stoichiometry of the materials, their morphology, and the phase composition and electrochemical performance have been studied. The effects of thermal annealing and decomposition processes on the structure are discussed in detail. The changes of Li content in materials were monitored by ICP spectrometry. It was established that the decomposition of the acetates at around 450 °C is a slurry-making process that compacts the powder. It was found that well lithiated samples with good life cycle and high capacity can be prepared using acetate precursors and a spray solution technique. The morphology, grain size and texturing can be controlled by the sintering time and temperature in combination with intermediate grinding.

  11. Preparation and characterization of sulfur-doped TiO(2)/Ti photoelectrodes and their photoelectrocatalytic performance.

    Science.gov (United States)

    Sun, Haijian; Liu, Huiling; Ma, Jun; Wang, Xiangyu; Wang, Bin; Han, Lei

    2008-08-15

    Sulfur-doped TiO(2)/Ti photoelectrodes were prepared by anodization and characterized by SEM, AFM, XRD, XPS, UV-vis and SPS. The results of investigation indicated that S(4+) and S(6+) were dispersed on the surface of TiO(2) nanoparticles. The doping with an appropriate amount of sulfur expanded the response range of TiO(2)/Ti photoelectrodes to visible light, and enhanced the separation of photoinduced electrons from cavities. The photoelectrocatalytic performance test run with sulfur-doped TiO(2)/Ti photoelectrodes under Xenon light indicated that Na(2)SO(3) concentration of 750 mg/L and voltage of 160 V were the optimal conditions for preparation of sulfur-doped TiO(2)/Ti photoelectrodes.

  12. Effects of Temperature and Method of Solution Preparation on the Performance of a Typical Red Mud Flocculent

    Science.gov (United States)

    Ferland, Pierre; Malito, John T.; Phillips, Everett C.

    Alcan International Ltd. in collaboration with Ondeo Nalco Company have carried out a fundamental study on the dissolution and performance of a 100% anionic polymer. The effects of method of preparation, solvent composition, temperature and exposure time on flocculent activity under conditions relevant to both atmospheric and pressure decantation were investigated. Flocculent activity was determined using static and dynamic settling tests, and the results were correlated with the reduced specific viscosity (RSV). For any given method of preparation of the flocculent solutions (makeup/dilution) the RSV tended to decrease with increasing solution ionic strength, independent of ionic speciation. While a significant loss in flocculent activity occurred with long exposure of the solution to high temperature, only a minor loss occurred in the short time required to flocculate and settle the mud in a decanter operating at 150 °C. Recent results in an actual plant pressure decanter appear to validate this conclusion.

  13. Preparation of high-performance ultrafine-grained AISI 304L stainless steel under high temperature and pressure

    Directory of Open Access Journals (Sweden)

    Peng Wang

    2016-08-01

    Full Text Available Bulk ultra-fine grained (UFG AISI 304L stainless steel with excellent mechanical properties was prepared by a high-temperature and high-pressure (HTHP method using nanocrystalline AISI 304L stainless steel powders obtained from ball milling. Samples were sintered in high-pressure conditions using the highest martensite content of AISI 304L stainless steel powders milled for 25 h. Analyses of phase composition and grain size were accomplished by X-ray diffraction and Rietveld refinement. By comparing the reverse martensite transformation under vacuum and HTHP treat, we consider that pressure can effectively promote the change in the process of transformation. Compared with the solid-solution-treated 304L, the hardness and yield strength of the samples sintered under HTHP are considerably higher. This method of preparation of UFG bulk stainless steel may be widely popularised and used to obtain UFG metallic materials with good comprehensive performance.

  14. Simple preparation of lotus-root shaped meso-/macroporous TiO₂ and their DSSC performances.

    Science.gov (United States)

    Hong, Jin-Yeon; Bae, Sang-Eun; Won, Yong Sun; Huh, Seong

    2015-06-15

    In pursuit of superior TiO2 photoanode materials for dye-sensitized solar cells (DSSCs), we prepared lotus-root shaped meso-/macroporous TiO2. The lotus-root shaped meso-/macroporous TiO2 was easily prepared by using a cetyltrimethylammonium hydroxide (CTAOH) template in aqueous solution. The crystallization of the as-prepared amorphous lotus-root shaped TiO2 was performed at 700 °C in air. Crystalline anatase phase with a very small portion of rutile phase was generated after the heat treatment at 700 °C and the BET surface area of crystalline lotus-root shaped meso-/macroporous TiO2 material (LR-700) was 30.0 m(2) g(-1). The wall of LR-700 displayed well-developed mesoporosity with a pore dimension of 28.3 nm. Periodically arranged microscale one-dimensional (1D) macropores were also observed in the particles. The photon-to-current conversion efficiencies (η) of LR-700 photoanodes in Grätzel type DSSCs were examined. The conversion efficiency of DSSC prepared by mixing nanoparticulate Evonik P25 and LR-700 (ratio=85:150 by mass) was 28% greater compared to the reference electrode using P25. Incident photon-to-current efficiencies (IPCE) of the DSSCs were dramatically improved by employing the photoanodes composed of a mixture of P25 and LR-700 but impedance analysis indicated that P25/LR-700 mixed cells have resistances similar to the standard P25 reference cell. Thus, photovoltaic performances could be improved mainly due to the increases of dye uptake and external quantum efficiency by using a mixed photoanode composed of LR-700 and nanocrystalline P25 particles.

  15. One-step preparation of nitrogen-doped graphene nanosheets for high-performance supercapacitors

    Science.gov (United States)

    Gao, Biaofeng; Zhou, Haitao; Yang, Jianhong

    2017-07-01

    Graphene nanosheets (GNs) have been successfully synthesized by one-step carbonization and simultaneous chemical activation of polyaniline (PANI) nanofibers, with large surface area (1759.5 m2 g-1), high pore volume (1.16 cm3 g-1) and a mesopore rich structure (volume in micropore/total ratio, 2.16%). The vital (NDs) become entrapped within a carbon lattice (to form GNs). GNs could be used as an outstanding electrode material for supercapacitors in EMIMBF4 with high cycling stability (more than 73% retention of the initial capacitance after 10,000 cycles). The symmetric supercapacitor has an excellent energy density of 170.2 Wh kg-1 (25 °C) at 0.5 A g-1, with an operating cell voltage of 4.0 V. Meanwhile, oriented activation with polymers of anisotropic geometry might be regarded as a novel process to prepare GNs.

  16. Preparation and Performance of an Adsorption Type Gel Plugging Agent as Enhanced Oil Recovery Chemical

    Directory of Open Access Journals (Sweden)

    Xiaoping Qin

    2015-01-01

    Full Text Available A novel adsorption type gel plugging agent (ATGPA was prepared using acrylamide (AM, acrylic acid (AA, diallyl dimethyl ammonium chloride (DMDAAC, 2-acrylamido-2-methylpropanesulfonate (AMPS, formaldehyde (HCHO, resorcinol (C6H6O2, and thiocarbamide (CH4N2S as raw materials under mild conditions. ATGPA was characterized by infrared (IR spectroscopy, elemental analysis, and scanning electron microscope (SEM. It was found that ATGPA exhibited higher elastic modulus (G′ and viscous modulus (G′′ than AM/AA gel plugging agent (AAGPA under the same scanning frequency. It was also found that ATGPA had moderate temperature resistance and salt tolerance. Core plugging tests results indicated that ATGPA could achieve up to higher plugging rate (PR than AAGPA (97.2% versus 95.7% at 65°C. In addition, ATGPA possessed stronger antiscouring ability by core plugging experiments at 65°C.

  17. Preparation and Adsorption Performances of Phragmites australis Activated Carbon with High Acidity

    Directory of Open Access Journals (Sweden)

    FU Cheng-kai

    2017-03-01

    Full Text Available For removal of heavy metals from wastewater and recycling the wetland plants, the present study investigated the viability of using silage of Phragmites australis (PA to prepare activated carbons (ACs with high acidity. BET surface area, porous texture and surface functional characteristics of ACs were analyzed by N2 adsorption/desorption, elemental analysis and Boehm titration method. ACs presented well-developed micro-porosity and favorable surface acidity. The sorption equilibrium data for Ni (Ⅱ and Cd (Ⅱ sorption onto ACs were analyzed by the Langmuir and Freundlich models. The Langmuir model was fitted well to the adsorption behavior. The properties of high surface acidity promoted the adsorption of heavy metals by the silage-treated ACs and the chemical sorption played the key role in the sorption process.

  18. Photocatalytic performance of Cu2O composite octahedra prepared by a propanetriol-reduced process

    Science.gov (United States)

    Zhang, Lihui; Wang, Xiangfu

    2014-12-01

    Cu2O and Ag/Cu2O composite octahedra were synthesized via a hydrothermal reaction of CuAc2 with urea in H2O-propanetriol binary solution by adjusting the quantity of AgNO3 at 180 °C for 10 h. The influence of reaction temperature and time on the morphology and phase of the products was investigated, and a possible growth mechanism of Cu2O octahedron was also proposed. The photocatalytic activities of the as-prepared Cu2O and Ag/Cu2O octahedra for the degradation of methyl orange aqueous solution were studied. The results show that they are effective photocatalysts for the degradation of methyl orange, and the photocatalytic ability of Ag/Cu2O composite is stronger than that of Cu2O octahedra, which are expected to be useful in the treatment of wastewaters.

  19. Preparation and photocatalytic degradation performance of Ag3PO4 with a two-step approach

    Science.gov (United States)

    Li, Jiwen; Ji, Xiaojing; Li, Xian; Hu, Xianghua; Sun, Yanfang; Ma, Jingjun; Qiao, Gaowei

    2016-05-01

    Ag3PO4 photocatalysts were prepared via two and one-step through a facile ion-exchange route. The photocatalysts were then characterized through powder X-ray diffraction, scanning electron microscopy and UV-vis diffuse reflectance spectroscopy. The photocatalytic activity of the samples was evaluated on the basis of the photocatalytic degradation of methyl orange (MO) and methylene blue (MB) under solar irradiation. The MO degradation rate of the Photocatalyst synthesized by the two-step ion-exchange route was 89.18% in 60 min. This value was four times that of the Photocatalyst synthesized by the one-step approach.The MB degradation rate was 97% in 40 min. After six cycling runs were completed, the MO degradation rate was 73%

  20. Preparation and photocatalytic performance of iodine-doped NaTaO3 nanoparticles.

    Science.gov (United States)

    Han, Peilin; Su, Yiguo; Meng, Yue; Wang, Shuwei; Jia, Qingyue; Wang, Xiaojing

    2011-11-01

    Iodine-doped NaTaO3 nanoparticles were prepared by hydrothermal conditions and explored as the visible-light-driven photocatalysts for photodegradation of methylene blue in water. It is found that I-doped NaTaO3 showed photodegradation efficiency superior over the un-doped NaTaO3. UV-Vis diffuse reflectance spectra indicate that the absorption edges shifted towards longer wavelength with increasing the iodine concentration. The energy band structure and the transient behavior of the photogenerated charge carriers for both un-doped and doped NaTaO3 powders were investigated using density functional theory. The improved photocatalytic activity under visible light for I-doped NaTaO3 may be caused by both the broadening of valence band that inhibited the recombination of e-h+ pairs and the narrowing of energy band gap due to the much negative energy levels in the bottom of conduction bands.

  1. Preparation, Characterization and Catalytic Performance of Nanometer Ceria-Zirconia Solid Solution

    Institute of Scientific and Technical Information of China (English)

    Hu Yucai; Wang Yinghui; Pan Junyan

    2004-01-01

    Ce0.6Zr0.4O2 solid solution was prepared by co-precipitation technique using hydrazine hydrate as precipitator.Various physico-chemical techniques such as XRD, FT-Raman, SEM, TEM, etc.were used to characterize the resultant powder.Meanwhile, its catalytic activity was evaluated in the synthesis of n-butyl acetate by the reaction of acetic acid and n-butyl alcohol.The results show that ceria-zirconia solid solution forms single cubic structure and its particle diameter is less than 100 nm.As a sort of solid acid, it possesses high catalytic activity and can be easily separated from reaction liquid.After it is used for ten times, its activity basically kees unchanging.

  2. Preparation and performance of a sulfur/graphene composite for rechargeable lithium-sulfur battery

    Science.gov (United States)

    Zhang, Feifei; Dong, Yunhui; Huang, Yun; Huang, Gang; Zhang, Xinbo; Wang, Limin

    2012-01-01

    The lithium-sulfur (Li-S) battery is a promising electrochemical system that has high theoretical capacity. The sulfur/graphene nanosheets (S/GNS) composite is prepared through thermal reduction between the sulfur (S) and graphene oxide (GO). The morphology and composition of the composite are analyzed by means of x-ray powder diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive spectroscopic (EDS) characterization. It is found that the element S distributed uniformly between the layers of GNS. Graphene with a two-dimensional structure of carbon atoms is employed as a conductive and absorbing agent for the S cathode materials of rechargeable Li-S battery. The S/GNS composite cathode shows a specific electrochemical capacity, which is about 1598 mAh g-1 S at the initial discharge and remains above 670 mAh g-1 after 80 cycles.

  3. Preparation and performance of rare earth Zr catalyst for reforming waste plastics cracking product

    Institute of Scientific and Technical Information of China (English)

    袁兴中; 曾光明; 陈晓青; 陈志勇; 鄢钢

    2003-01-01

    The rare earth Zr catalyst, whose carrier was Al2O3, was prepared by co-precipitation with Zr(NO3)2,Al(NO3 )3, and(NH2)2CO as the raw materials. The obtained catalyst was used to reform the waste plastic crackingproduct. As the Zr content in the catalyst increases, the yields of gasoline, gas, and the rate of carbon deposition in-crease, but the yields of diesel and heavy oil decrease. The optimum Zr content of the catalyst is 5%. At 290 ℃,with this most suitable catalyst, the yield of liquid fuel oil is the highest, about 86.10%, and research octance num-ber(RON) of the gasoline is 92.15.

  4. [Preparation and Performance of Ultrafast γ-CuI Scintillation Conversion Screen].

    Science.gov (United States)

    Xia, Ming; Gu, Mu; Liu, Xiao-lin; Liu, Bo; Huang, Shi-ming; Ni, Chen

    2015-04-01

    Micro-columnar structured γ-CuI scintillation conversion screen with columnar diameter in the micrometer and thickness about 17 µm were prepared by thermal evaporation method on quartz substrates with different temperatures. X-ray excited luminescence spectra of the screens show two peaks located at 430 nm and near 700 nm, which correspond to the fast and slow emission components, respectively. The fast one dominated. The intensity of 430 nm peak decreased as the substrate temperature rose from 170 °C to 210 °C. At the same time the intensity of 700 nm band increased. The changes may be attributed to the iodine loss from screen caused by the substrate temperature. The phenomenon of iodine loss was observed by the Rutherford backscattering experiment. The crystal structure of the screens presents (111) preferred orientation, which is independent of the substrate temperature. As the temperature rose to 210 °C, two weak additional peaks of (220) and (420) γ-CuI crystal planes in X-ray diffraction patterns appeared due to the increase in kinetic energy of CuI molecules. The scanning electron microscopy images of the screens showed that the columnar structure was improved when the substrate temperature increased from 170 °C to 190 °C, but it would be degenerated when the temperature continued to rise to 210 °C because of the surface and bulk diffusion effects of the depositing molecules. Finally, the spatial resolution of the γ-CuI scintillation screens was measured by knife-edge method, and they are 4.5, 7.2 and 5.6lp · mm(-1) for the screens prepared at the substrates temperatures of 170, 190 and 210 °C, respectively. The result shows that micro-column structure could improve the spatial resolution of γ-CuI scintillation screen.

  5. Lyophilized Carnobacterium divergens AS7 bacteriocin preparation improves performance of broiler chickens challenged with Clostridium perfringens

    DEFF Research Database (Denmark)

    Jozefiak, D; Sip, A; Rutkowski, A;

    2012-01-01

    The present study aimed to investigate the effects of Carnobacterium divergens AS7 bacteriocin (divercin AS7) on growth performance, digestibility, fermentation processes, selected microbial populations, and histomorphology in broiler chickens challenged with a mixture of 3 Clostridium perfringens...

  6. Psychophysiological activation during preparation, performance, and recovery in high- and low-anxious music students.

    Science.gov (United States)

    Studer, Regina Katharina; Danuser, Brigitta; Wild, Pascal; Hildebrandt, Horst; Gomez, Patrick

    2014-03-01

    The present study provides a comprehensive view of (a) the time dynamics of the psychophysiological responding in performing music students (n = 66) before, during, and after a private and a public performance and (b) the moderating effect of music performance anxiety (MPA). Heart rate (HR), minute ventilation (VE), and all affective and somatic self-report variables increased in the public session compared to the private session. Furthermore, the activation of all variables was stronger during the performances than before or after. Differences between phases were larger in the public than in the private session for HR, VE, total breath duration, anxiety, and trembling. Furthermore, while higher MPA scores were associated with higher scores and with larger changes between sessions and phases for self-reports, this association was less coherent for physiological variables. Finally, self-reported intra-individual performance improvements or deteriorations were not associated with MPA. This study makes a novel contribution by showing how the presence of an audience influences low- and high-anxious musicians' psychophysiological responding before, during and after performing. Overall, the findings are more consistent with models of anxiety that emphasize the importance of cognitive rather than physiological factors in MPA.

  7. Preparation, investigation of metal ion removal and flocculation performances of grafted hydroxyethyl starch.

    Science.gov (United States)

    Kolya, Haradhan; Tripathy, Tridib

    2013-11-01

    Ceric ion induced graft copolymerization of N,N-dimethyl acrylamide (DMA) and acryl amide (AM) were carried out onto the hydroxyethyl starch (HES). These grafted copolymers were used for the removal of metal ions from their aqueous solutions. Flocculation performances of the synthesized graft copolymers were evaluated in 1.0 wt% silica suspensions. A comparative study of the flocculation performances of the synthetic graft copolymers was also made. The different factors affecting metal ion absorption, namely pH, treatment time, temperature and polymer dose were studied. A comparative study of the metal ion removal capacity of the two synthetic graft copolymers was also made in five metal ions namely Ni(II), Zn(II), Cu(II), Pb(II) and Hg(II). The metal ion removal capacity follows the order Hg(II)>Cu(II)>Zn(II)>Ni(II)>Pb(II) in both the two synthetic polymers. Between the two graft copolymers, graft copolymer based on AM shows better performance than that based on DMA in all the metal solutions. But the flocculation performance of DMA based graft copolymer showed better performances than that AM based graft copolymer. The former also performed best when compared to the commercial flocculants in the same suspension.

  8. Preparation for action: psychophysiological activity preceding a motor skill as a function of expertise, performance outcome, and psychological pressure.

    Science.gov (United States)

    Cooke, Andrew; Kavussanu, Maria; Gallicchio, Germano; Willoughby, Adrian; McIntyre, David; Ring, Christopher

    2014-04-01

    Knowledge of the psychophysiological responses that characterize optimal motor performance is required to inform biofeedback interventions. This experiment compared cortical, cardiac, muscular, and kinematic activity in 10 experts and 10 novices as they performed golf putts in low- and high-pressure conditions. Results revealed that in the final seconds preceding movement, experts displayed a greater reduction in heart rate and EEG theta, high-alpha, and beta power, when compared to novices. EEG high-alpha power also predicted success, with participants producing less high-alpha power in the seconds preceding putts that were holed compared to those that were missed. Increased pressure had little impact on psychophysiological activity. It was concluded that greater reductions in EEG high-alpha power during preparation for action reflect more resources being devoted to response programming, and could underlie successful accuracy-based performance.

  9. One-step preparation and photocatalytic performance of vanadium doped TiO{sub 2} coatings

    Energy Technology Data Exchange (ETDEWEB)

    Vasilić, R., E-mail: rastko.vasilic@ff.bg.ac.rs [University of Belgrade, Faculty of Physics, Studentski trg 12-16, 11000 Belgrade (Serbia); Stojadinović, S. [University of Belgrade, Faculty of Physics, Studentski trg 12-16, 11000 Belgrade (Serbia); Radić, N. [University of Belgrade, Institute of Chemistry, Technology and Metallurgy, Department of Catalysis and Chemical Engineering, Njegoševa 12, 11000 Belgrade (Serbia); Stefanov, P. [Institute of General and Inorganic Chemistry, Bulgarian Academy of Sciences, Acad. G. Bonchev Str., Block 11, Sofia 1113 (Bulgaria); Dohčević-Mitrović, Z. [University of Belgrade, Institute of Physics, Pregrevica 118, 11080 Belgrade (Serbia); Grbić, B. [University of Belgrade, Institute of Chemistry, Technology and Metallurgy, Department of Catalysis and Chemical Engineering, Njegoševa 12, 11000 Belgrade (Serbia)

    2015-02-01

    In this paper, we have investigated one-step preparation of vanadium doped TiO{sub 2} coatings formed by plasma electrolytic oxidation (PEO) of titanium in electrolyte containing 10 g/L Na{sub 3}PO{sub 4}·12H{sub 2}O + 0.5 g/L NH{sub 4}VO{sub 3}. The morphology, phase structure, and elemental composition of the formed coatings were characterized by atomic force microscopy (AFM), x-ray diffraction (XRD), and x-ray photoelectron spectroscopy (XPS) techniques. Ultraviolet–visible diffuse reflectance spectroscopy (UV–Vis DRS) was employed to evaluate the band gap energy of obtained coatings. Vanadium doped TiO{sub 2} coatings are partly crystallized and mainly composed of anatase phase TiO{sub 2}, with up to about 2 wt% of vanadium present in the surface layer of the oxide. The valence band photoelectron spectra and UV–Vis DRS showed that vanadium doped TiO{sub 2} coatings exhibit notable red shift with respect to the pure TiO{sub 2} coatings. The photocatalytic activity was evaluated by monitoring the degradation of methyl orange under simulated sunlight conditions. Photocatalytic activity of vanadium doped TiO{sub 2} coatings increases with PEO time. Prolonged PEO times result in higher roughness of obtained coatings, thus increasing surface area available for methyl orange degradation. Vanadium doped TiO{sub 2} coatings obtained after 180 s of PEO time exhibit the best photocatalytic activity and about 67% of methyl orange is degraded after 12 h of irradiation under simulated sunlight. - Highlights: • One-step preparation of V-doped TiO{sub 2} coatings in 10 g/L Na{sub 3}PO{sub 4}·12H{sub 2}O + 0.5 g/L NH{sub 4}VO{sub 3}. • Properties of obtained coatings strongly depend on microdischarge characteristics. • Band gap of V-doped TiO{sub 2} coatings is shifted towards red side of the spectrum. • V-doped TiO{sub 2} coatings have better photocatalytic activity than pure TiO{sub 2}. • After 12 h of simulated sunlight irradiation, 67% of

  10. Non-Precious Metal Catalysts Prepared By Zeolitic Imidazolate Frameworks: The Ligand Influence to Morphology and Performance

    Energy Technology Data Exchange (ETDEWEB)

    Barkholtz, H. M.; Chong, L.; Kaiser, Z. B.; Liu, D. -J

    2016-08-01

    A new, “one-pot” synthesis to produce highly active non-PGM electrocatalysts for PEM fuel cells was previously developed by pyrolyzing Fe doped zeolitic imidazolate framework (ZIF) materials prepared by solid-state interaction. Excellent catalytic oxygen reduction reaction (ORR) activities were found through rotating ring-disk electrode (RRDE) and single fuel cell tests. In this study, we compared the ORR activities and structural properties of two catalysts derived from ZIFs containing imidazole and methyl imidazole ligands, respectively. Our results indicate that alkyl group substitution in the imidazolate ligand has a profound effect on the final catalyst performance.

  11. Facile preparation of reduced graphene oxide - ruthenium oxide nanocomposite electrodes for high-performance supercapacitors

    Science.gov (United States)

    Amir, Fatima; Pham, Viet; Dickerson, James; Winthrop University Team; CFN-Brookhaven National Lab Team

    2015-03-01

    Herein we report a facile approach of synthesis of graphene oxide (GO) sheets modified with ruthenium oxide (RuO2) nanoparticles, followed by a reduction of graphene oxide in an alkaline medium. The as-prepared reduced graphene oxide (rGO)/ruthenium oxide (RuO2) nanocomposite was used for the fabrication of a symmetric supercapacitor. The specific capacitance and charge-discharge periods of the supercapacitor were found to be dependent on both the structural and morphological properties, and the electrolytes used. Surface morphology analysis using scanning electron microscopy (SEM) shows the RuO2 nanoparticles decorating rGO sheets, comprising a highly porous surface. Structural analysis obtained by x-ray diffraction (XRD) revealed an amorphous structure that is necessary to achieve a high cycling rate capability. The electrochemical properties of rGO/RuO2 were measured in a two electrodes system, using two different electrolytes: H2SO4andNa2SO4. The specific capacitance of rGO/RuO2 in H2SO4 was found to be 318 F/g, and is much higher than that of Na2SO4 (184 F/g).

  12. Architectured morphologies of chemically prepared NiO/MWCNTs nanohybrid thin films for high performance supercapacitors.

    Science.gov (United States)

    Gund, Girish S; Dubal, Deepak P; Shinde, Sujata S; Lokhande, Chandrakant D

    2014-03-12

    The preparation of nanostructured metal oxide decorated on multiwalled carbon nanotubes (MWCNTs) nanohybrid films through simple, scalable, additive-free, binderless, and cost-effective route has fascinated significant attention not only in fundamental research areas but also its commercial applications, in order to reduce the growing environmental pollution and the cost of electrode fabrication. Here, we report the fabrication of highly flexible electrode with NiO/MWCNTs nanohybrid thin films directly on stainless steel substrate using successive ionic layer adsorption and reaction (SILAR) method. The impact of ratio of adsorption and reaction cycles on structural, surface areas and electrochemical properties of NiO/MWCNTs nanohybrids was investigated. X-ray diffraction measurements confirm the hybridization and face centered cubic (FCC) crystal structure of NiO in NiO/MWCNTs nanohybrids. In addition, these nanohybrids exhibit excellent surface properties such as uniform surface morphology, good surface area, pore volume, and uniform pore size distribution. The electrochemical tests demonstrate the highest specific capacitance of 1727 F g(-1) at 5 mA cm(-2) of current density with 91% capacitance retention after 2000 cycles. In addition, the Ragone plot confirms the better power and energy densities for all NiO/MWCNTs nanohybrids. The attractive electrochemical capacitive activity revealed by NiO/MWCNTs nanohybrid electrode proposes that it is an auspicious respondent for future energy storage application.

  13. Preparation, microstructure and degradation performance of biomedical magnesium alloy fine wires

    Directory of Open Access Journals (Sweden)

    Jing Bai

    2014-10-01

    Full Text Available With the development of new biodegradable Mg alloy implant devices, the potential applications of biomedical Mg alloy fine wires are realized and explored gradually. In this study, we prepared three kinds of Mg alloy fine wires containing 4 wt% RE(Gd/Y/Nd and 0.4 wt% Zn with the diameter less than 0.4 μm through casting, hot extruding and multi-pass cold drawing combined with intermediated annealing process. Their microstructures, mechanical and degradation properties were investigated. In comparison with the corresponding as-extruded alloy, the final fine wire has significantly refined grain with an average size of 3–4 μm, and meanwhile shows higher yield strength but lower ductility at room temperature. The degradation tests results and surface morphologies observations indicate that Mg–4Gd–0.4Zn and Mg–4Nd–0.4Zn fine wires have similar good corrosion resistance and the uniform corrosion behavior in SBF solution. By contrast, Mg–4Y–0.4Zn fine wire shows a poor corrosion resistance and the pitting corrosion behavior.

  14. Performance of flexible capacitors based on polypyrrole/carbon fiber electrochemically prepared from various phosphate electrolytes

    Energy Technology Data Exchange (ETDEWEB)

    Yuan, Wei; Han, Gaoyi, E-mail: han_gaoyis@sxu.edu.cn; Chang, Yunzhen; Li, Miaoyu; Xiao, Yaoming, E-mail: ymxiao@sxu.edu.cn; Zhou, Haihan; Zhang, Ying; Li, Yanping

    2016-11-30

    Highlights: • PPy/CFs have been fabricated by electrodepositing polypyrrole on carbon fibers. • The electrolytes in deposition solution have effect on PPy/CFs’ capacitive behavior. • Cells of PPy/CFs obtained from NaH{sub 2}PO{sub 4} electrolyte has good stability in PVA/H{sub 3}PO{sub 4}. - Abstract: In order to investigate the influence of electrolytes in electro-deposition solution on the capacitive properties of polypyrrole (PPy), we have chosen phosphoric acid, phosphate, hydrogen phosphate and dihydrogen phosphate as electrolyte in deposition solution respectively and electrochemically deposited PPy on carbon fibers (CFs) via galvanostatic method. The morphologies of the PPy/CFs samples have been characterized by scanning electron microscope. The specific capacitance of PPy/CFs samples has been evaluated in different electrolytes through three-electrode test system. The assembled flexible capacitors by using PPy/CFs as electrodes and H{sub 3}PO{sub 4}/polyvinyl alcohol as gel electrolyte have been systematically measured by cyclic voltammetry, galvanostatic charge/discharge and electrochemical impedance spectroscopy. The results show that the electrochemical capacitors based on PPy/CFs prepared from deposition solution containing NaH{sub 2}PO{sub 4}·2H{sub 2}O electrolyte exhibit higher specific capacitance, flexibility and excellent stability (retaining 96.8% of initial capacitance after 13,000 cycles), and that three cells connected in series can power a light-emitting diode.

  15. Preparation and Performance of Magneto-optical Glasses Doped with Tb3+/Dy3+

    Institute of Scientific and Technical Information of China (English)

    YIN Hairong; ZHAO Gaoyang; LIU Pan; WANG Shunni; GUO Hongwei

    2014-01-01

    In order to increase the content of rare-earth oxides in magneto-optical glass and improve the Verdet constant, the rare-earth doped ternary Ga2O3-B2O3-SiO2(GBS) system magneto-optical glasses were prepared by the melt quenching technique. The influence of Tb3+and Dy3+ions on the structure of GBS glasses was investigated using FTIR, DSC and Faraday rotations. The experimental results showed that the content of rare-earth oxides in the glasses with the double incorporation of Tb2O3 and Dy2O3 was higher. The crystallization parameterβachieved the maximum 0.48 with Tb3+/Dy3+content of 35mol%. Terbium oxide existed mainly in [TbO3] units in the glasses and [TbO4] units were converted into [TbO3] with increasing Tb2O3 content. As Ga3+ion is larger than B3+ion in radius, leading to an increasing of the glass network gap and improvement in the ability of accommodating rare earth ions, Verdet constant increased.

  16. Ordered macroporous quercetin molecularly imprinted polymers: Preparation, characterization, and separation performance.

    Science.gov (United States)

    Feng, Yonggang; Liu, Qin; Ye, Lifang; Wu, Quanzhou; He, Jianfeng

    2017-02-01

    Ordered macroporous molecularly imprinted polymers were prepared by a combination of the colloidal crystal templating method and the molecular imprinting technique by using SiO2 colloidal crystal as the macroporogen, quercetin as the imprinting template, acrylamide as the functional monomer, ethylene glycol dimethacrylate as the cross-linker and tetrahydrofuran as the solvent. Scanning electron microscopy and Brunauer-Emmett-Teller measurements show that the ordered macroporous molecularly imprinted polymers have a more regular macroporous structure, a narrower pore distribution and a greater porosity compared with the traditional bulk molecularly imprinted polymers. The kinetic and isothermal adsorption behaviors of the polymers were investigated. The results indicate that the ordered macroporous molecularly imprinted polymers have a faster intraparticle mass transfer process and a higher adsorption capacity than the traditional bulk molecularly imprinted polymers. The ordered macroporous molecularly imprinted polymers were further employed as a sorbent for a solid-phase extraction. The results show that the ordered macroporous molecularly imprinted polymers can effectively separate quercetin from the Gingko hydrolysate.

  17. Performance of flexible capacitors based on polypyrrole/carbon fiber electrochemically prepared from various phosphate electrolytes

    Science.gov (United States)

    Yuan, Wei; Han, Gaoyi; Chang, Yunzhen; Li, Miaoyu; Xiao, Yaoming; Zhou, Haihan; Zhang, Ying; Li, Yanping

    2016-11-01

    In order to investigate the influence of electrolytes in electro-deposition solution on the capacitive properties of polypyrrole (PPy), we have chosen phosphoric acid, phosphate, hydrogen phosphate and dihydrogen phosphate as electrolyte in deposition solution respectively and electrochemically deposited PPy on carbon fibers (CFs) via galvanostatic method. The morphologies of the PPy/CFs samples have been characterized by scanning electron microscope. The specific capacitance of PPy/CFs samples has been evaluated in different electrolytes through three-electrode test system. The assembled flexible capacitors by using PPy/CFs as electrodes and H3PO4/polyvinyl alcohol as gel electrolyte have been systematically measured by cyclic voltammetry, galvanostatic charge/discharge and electrochemical impedance spectroscopy. The results show that the electrochemical capacitors based on PPy/CFs prepared from deposition solution containing NaH2PO4·2H2O electrolyte exhibit higher specific capacitance, flexibility and excellent stability (retaining 96.8% of initial capacitance after 13,000 cycles), and that three cells connected in series can power a light-emitting diode.

  18. Dispersion Performance of Methanol-Diesel Emulsiifed Fuel Prepared by High Gravity Technology

    Institute of Scientific and Technical Information of China (English)

    Jiao Weizhou; Li Jing; Liu Youzhi; Zhang Qiaoling; Liu Wenli; Xu Chengcheng; Guo Liang

    2014-01-01

    A new continuous process for preparing methanol-diesel emulsified fuel with an Impinging Stream-Rotating Packed Bed is proposed. The droplet size of dispersed phase (methanol) of the emulsiifed fuel has a signiifcant effect on the combustion of methanol-diesel emulsiifed fuel. In this paper, the methanol-diesel emulsiifed fuel uses diesel as the continu-ous phase and methanol as the dispersed phase. The Sauter mean diameter of the dispersed phase of methanol-diesel emulsi-ifed fuel was characterized with microphotography and arithmetic method. The experimental result showed that the Sauter mean diameter of the dispersed phase, which was decreased with the augmentation of the high gravity factor, liquid lfow rate and emulsiifer dosage, was inversely proportional to the methanol content. The Sauter mean diameter of the dispersed phase can be controlled and adjusted in the range of 12-40μm through the change of operating conditions. The correlative expressions of the Sauter mean diameter of emulsiifed fuel were obtained and the calculated values agreed well with the ex-perimental values.

  19. Preparation and Properties of Organically Modified Sepiolite/ High-performance Epoxy Nanocomposites

    Institute of Scientific and Technical Information of China (English)

    LU Hai-jun

    2006-01-01

    Fibrous organic sepiolites (OSEP) and novel epoxy/OSEP nanocomposites were prepared, and different methods were investigated to produce an intercalated/exfoliated structure of OSEP. Experimental results show that the modifier molecules can be easily adsorbed by the sepiolite, but the layer space (d001) of the sepiolite, linked by means of covalent bond, remains unchanged. A proper method to solve this problem appears to exert large shearing force on the original sepiolite followed by its organic modification (OSEP2). The morphology observation shows that there are formed an even dispersion of nano-sized OSEP2 fibers in epoxy resin and a structure intercalated by epoxy molecules, which lead to significantly improved mechanical properties. Impact strength of the epoxy/ OSEP2 nanocomposite increases from 32.1 kJ/m2 to 44.4 kJ/m2, 38.3% higher than that of pristine matrix with 3 wt% OSEP2 content. It is also noted that the flexural strength of the OSEP/epoxy composites has risen by about 3% higher than that of the pure epoxy resin.

  20. Preparation, microstructure and degradation performance of biomedical magnesium alloy fine wires

    Institute of Scientific and Technical Information of China (English)

    Jing Bai; Zhejun Tang; Lingling Yin; Ye Lu; Yiwei Gan; Feng Xue; Chenglin Chu; Jingli Yan; Kai Yan; Xiaofeng Wan

    2014-01-01

    With the development of new biodegradable Mg alloy implant devices, the potential applications of biomedical Mg alloy fine wires are realized and explored gradually. In this study, we prepared three kinds of Mg alloy fine wires containing 4 wt%RE(Gd/Y/Nd) and 0.4 wt%Zn with the diameter less than 0.4μm through casting, hot extruding and multi-pass cold drawing combined with intermediated annealing process. Their microstructures, mechanical and degradation properties were investigated. In comparison with the corresponding as-extruded alloy, the final fine wire has significantly refined grain with an average size of 3–4μm, and meanwhile shows higher yield strength but lower ductility at room temperature. The degradation tests results and surface morphologies observations indicate that Mg–4Gd–0.4Zn and Mg–4Nd–0.4Zn fine wires have similar good corrosion resistance and the uniform corrosion behavior in SBF solution. By contrast, Mg–4Y–0.4Zn fine wire shows a poor corrosion resistance and the pitting corrosion behavior.

  1. Preparation of Stellerite Loading Titanium Dioxide Photocatalyst and Its Catalytic Performance on Methyl Orange

    Directory of Open Access Journals (Sweden)

    Hua Chen

    2015-01-01

    Full Text Available TiO2/stellerite composite photocatalysts were prepared by dispersing TiO2 onto the surface of HCl, NaOH, or NaCl treated stellerite using a sol-gel method. The materials were characterized by scanning electron microscopy (SEM, energy dispersive X-ray (EDX, Fourier transform infrared spectroscopy (FT-IR, BET surface area analysis, and X-ray diffraction (XRD. HCl and NaCl modification result in the promotion of the pore formation at the stellerite surfaces and induced the microscopic changes, while the surface morphology and structure of the stellerite were almost ruined by NaOH modification. Supported TiO2 calcinated at 200°C presented anatase structure. The photocatalytic degradation activities of TiO2 loaded HCl and NaCl modified stellerite were better than that of natural stellerite, accompanied with increasing specific surface area. On the contrary, NaOH modification induced the loss of photocatalytic ability of composite due to the generation of silicates.

  2. Preparation of metal oxide doped ACNFs and their adsorption performance for low concentration SO2

    Institute of Scientific and Technical Information of China (English)

    Hong-quan Yu; Yan-bo Wu; Tie-ben Song; Yue Li; Yu Shen

    2013-01-01

    Metal oxide (TiO2 or Co3O4) doped activated carbon nanofibers (ACNFs) were prepared by electrospinning. These nanofibers were characterized by X-ray diff raction (XRD), scanning electron microscopy (SEM), and Brunner-Emmett-Teller method (BET). The results show that the average diameters of ACNFs were within the range of 200-500 nm, and the lengths were several tens of micrometers. The specific surface areas were 1146.7 m2/g for TiO2-doped ACNFs and 1238.5 m2/g for Co3O4-doped ACNFs, respectively. The electrospun nanofibers were used for adsorption of low concentration sulfur dioxide (SO2). The results showed that the adsorption rates of these ACNFs increased with an increase in SO2concentration. When the SO2 concentration was 1.0 µg/mL, the adsorption rates of TiO2-doped ACNFs and Co3O4-doped ACNFs were 66.2%and 67.1%, respectively. The adsorption rate also increased as the adsorption time increased. When the adsorption time was 40 min, the adsorption rates were 67.6%and 69.0%for TiO2-doped ACNFs and Co3O4-doped ACNFs, respectively. The adsorption rate decreased as the adsorption temperature increased below 60˚C, while it increased as the adsorption temperature increased to more than 60◦C.

  3. Preparation and photoelectrochemical performance of TiO2/Ag2Se interface composite film

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Coupling TiO2 with a narrow band gap semiconductor acting as the photosensitizer has attracted much attention in solar energy exploitation. In this work,the porous TiO2 film was first formed on the conducting glass plate (CGP) substrate by the decomposition of polyethylene glycol (PEG) mixing in titanium hydroxide sol at 450℃. Then,the TiO2/Ag2Se interface composite film was fabricated by interface reaction of AgNO3 with NaSeSO3 on the activated surface of porous TiO2 film. The results of SEM and XRD analyses indicated that the porous TiO2 layer was made up of the anatase crystal,and the Ag2Se layer was made up of congregative small particles that have low-temperature α-phase structure. Due to its efficient charge separation for the photo-induced electron-hole pairs,the TiO2/Ag2Se interface composite film as-prepared has good photovoltaic property and high photocurrent response for visible light,which have been confirmed by the photoelectrochemical measurements.

  4. Performance of food safety management systems in poultry meat preparation processing plants in relation to Campylobacter spp. contamination.

    Science.gov (United States)

    Sampers, Imca; Jacxsens, Liesbeth; Luning, Pieternel A; Marcelis, Willem J; Dumoulin, Ann; Uyttendaele, Mieke

    2010-08-01

    A diagnostic instrument comprising a combined assessment of core control and assurance activities and a microbial assessment instrument were used to measure the performance of current food safety management systems (FSMSs) of two poultry meat preparation companies. The high risk status of the company's contextual factors, i.e., starting from raw materials (poultry carcasses) with possible high numbers and prevalence of pathogens such as Campylobacter spp., requires advanced core control and assurance activities in the FSMS to guarantee food safety. The level of the core FSMS activities differed between the companies, and this difference was reflected in overall microbial quality (mesophilic aerobic count), presence of hygiene indicators (Enterobacteriaceae, Staphylococcus aureus, and Escherichia coli), and contamination with pathogens such as Salmonella, Listeria monocytogenes, and Campylobacter spp. The food safety output expressed as a microbial safety profile was related to the variability in the prevalence and contamination levels of Campylobacter spp. in poultry meat preparations found in a Belgian nationwide study. Although a poultry meat processing company could have an advanced FSMS in place and a good microbial profile (i.e., lower prevalence of pathogens, lower microbial numbers, and less variability in microbial contamination), these positive factors might not guarantee pathogen-free products. Contamination could be attributed to the inability to apply effective interventions to reduce or eliminate pathogens in the production chain of (raw) poultry meat preparations.

  5. Preparation of morphology-controllable polyaniline and polyaniline/graphene hydrogels for high performance binder-free supercapacitor electrodes

    Science.gov (United States)

    Luo, Jinwei; Zhong, Wenbin; Zou, Yubo; Xiong, Changlun; Yang, Wantai

    2016-07-01

    Polyaniline (PANI) and its composite hydrogels have been considered as a unique supercapacitor electrode material due to their three dimensional (3D) porous structures, formed conducting networks, high specific surface areas and fast electron/ion transfer. Herein, dendritic and long fibrous PANI nanostructure hydrogels (PDH and PFH), dendritic PNAI nanofiber/graphene and long PANI nanofibers/Nitrogen-doped graphene composite hydrogels (PGH and PNGH) were prepared by integration polymerization of aniline and hydrothermal process. It was found that the addition of p-Phenylenediamine (PPD) not only controlled the morphologies of PANI from dendritic to long fibrous, but also facilitated the graphene oxide (GO) into nitrogen-doped graphene. Furthermore, after freeze-drying, PDH and PGH exhibited a max compressive strength of 9.5 and 9.6 KPa, respectively; while the max compressive strength of PFH and PNGH constructed with long PANI nanofiber is 79.9 and 75.8 KPa, respectively. Directly using these prepared hydrogels as electrodes for supercapacitors, it was found that PDH, PFH, PGH and PNGH exhibited high specific capacitances of 448.6, 470, 540.9 and 610 F g-1, respectively, at the current density of 1 A g-1. It is expected that the prepared PDH, PFH, PGH and PNGH can be directly applied in the field of high performance energy storage devices.

  6. High Performance Liquid Chromatography for the Determina- tion of Metoclopramide in Pharmaceutical Preparations Using Pre-column Derivatization with Fluorescamine

    Institute of Scientific and Technical Information of China (English)

    Tatar Ulu, Sevgi

    2012-01-01

    A simple, rapid and sensitive high performance liquid chromatography (HPLC) method was developed for the determination of metoclopramide in pharmaceutical preparation. The method is based on the derivatization of metoclopramide with fluorescamine. The separation was achieved on a C18 column using methanol-water (70 : 30, V/V) mobile phase. Fluorescence detector was used at the excitation and emission of 403 and 485 nm, respectively. The method was validated for linearity, limit of detection, limit of quantification, precision, accuracy, recovery, robust- ness and system suitability. The assay was linear over the concentration range of 100-2000 ng/mL. The mean recovery was 100.37%. The proposed method was successfully applied to the assay of metoclopramide in tablet preparation. The preparation was also analyzed with an official method and statistical comparison by t- and F-tests revealed that there was no significant difference between the results of the two methods with respect to mean values and standard deviations at the 95% confidence level.

  7. Research Linking Teacher Preparation and Student Performance: Teacher Education Yearbook XII

    Science.gov (United States)

    Guyton, Edith M., Ed.; Dangel, Julie Rainer, Ed.

    2004-01-01

    The case studies, research, and projects presented here strike at the very heart of effective teaching. The specific practices to improve student performance will spark classroom discussion and improve teacher practice. After a foreword by Frances van Tassell and an introduction by Edith M. Guyton and Julie Rainer Dangel, this book is divided into…

  8. Performance of hybrid programming models for multiscale cardiac simulations: preparing for petascale computation.

    Science.gov (United States)

    Pope, Bernard J; Fitch, Blake G; Pitman, Michael C; Rice, John J; Reumann, Matthias

    2011-10-01

    Future multiscale and multiphysics models that support research into human disease, translational medical science, and treatment can utilize the power of high-performance computing (HPC) systems. We anticipate that computationally efficient multiscale models will require the use of sophisticated hybrid programming models, mixing distributed message-passing processes [e.g., the message-passing interface (MPI)] with multithreading (e.g., OpenMP, Pthreads). The objective of this study is to compare the performance of such hybrid programming models when applied to the simulation of a realistic physiological multiscale model of the heart. Our results show that the hybrid models perform favorably when compared to an implementation using only the MPI and, furthermore, that OpenMP in combination with the MPI provides a satisfactory compromise between performance and code complexity. Having the ability to use threads within MPI processes enables the sophisticated use of all processor cores for both computation and communication phases. Considering that HPC systems in 2012 will have two orders of magnitude more cores than what was used in this study, we believe that faster than real-time multiscale cardiac simulations can be achieved on these systems.

  9. Quantification of six bioactive compounds in Zhenqi Fuzheng preparation by high-performance liquid chromatography couple

    Institute of Scientific and Technical Information of China (English)

    Yi-Kai Shi; Fang Cui; Fang-Di Hu; Ying-Yan Bi; Yu-Feng Ma; Shi-Lan Feng

    2011-01-01

    A simple and accurate high-performance liquid chromatography(HPLC)coupled with diode array detector(DAD)and evaporative light scattering detector(ELSD)was established for the determination of six bioactive compounds in Zhenqi Fuzheng preparation(ZFP).The

  10. Research Linking Teacher Preparation and Student Performance: Teacher Education Yearbook XII

    Science.gov (United States)

    Guyton, Edith M., Ed.; Dangel, Julie Rainer, Ed.

    2004-01-01

    The case studies, research, and projects presented here strike at the very heart of effective teaching. The specific practices to improve student performance will spark classroom discussion and improve teacher practice. After a foreword by Frances van Tassell and an introduction by Edith M. Guyton and Julie Rainer Dangel, this book is divided into…

  11. VT Maintenance District Boundaries

    Data.gov (United States)

    Vermont Center for Geographic Information — Vermont has eight transportation maintenance districts which are responsible for all maintenance activities on state highways, and for providing technical assistance...

  12. Preparation and characterization of a lipoid adsorption material and its atrazine removal performance

    Institute of Scientific and Technical Information of China (English)

    Zhiqiang Chen; Qinxue Wen; Jiaxiang Lian; Nanqi Ren

    2011-01-01

    A novel adsorbent named lipoid adsorption material (LAM),with a hydrophobic nucleolus (triolein) and a hydrophilic membrane structure (polyamide),was synthesized to remove hydrophobic organic chemicals (HOCs) from solution.Triolein,a type of lipoid,was entrapped by the polyamide membrane through an interfacial polymerization reaction.The method of preparation and the structure of the LAM were investigated and subsequent experiments were conducted to determine the characteristics of atrazine (a type of HOC) removal from wastewater using LAM as the adsorbent.The results showed that LAM had a regular structure compared with the prepolymer,where compact particles were linked with each other and openings were present in the structure of the LAM in which the fat drops formed from triolein were entrapped.In contrast to the atrazine adsorption behavior of powdered activated carbon (PAC),LAM showed a persistent adsorption capacity for atrazine when initial concentrations of 0.57,1.12,8.31 and 19.01 mg/L were present,and the equilibrium time was 12 hr.Using an 8 mg/L initial concentration of atrazine as an indicator of HOCs in aqueous solution,experiments on the adsorption capacity of the LAM showed 69.3% removal within 6-12 hr contact time,which was close to the 75.5%removal of atrazine by PAC.Results indicated that LAM has two atrazine removal mechanisms,namely the bioaccumulation of atrazine by the nucleous material and physical adsorption to the LAM membrane.Bioaccumulation was the main removal mechanism.

  13. Preparation and performance of tubular nanoflaky (Ni, Co, Mn) oxides with hierarchical mesoporous structure

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Hao; Fu, Yanqing; Wang, Xianyou, E-mail: wxianyou@yahoo.com; Gao, Jiao; Zhang, Youwei; Zhao, Qinglan

    2015-08-05

    Highlights: • The nickel cobalt manganese oxide with nanosheet-like nanotube structure is firstly reported. • The novel composite possess high specific surface area of 134.1 m{sup 2} g{sup −1}. • The novel composite deliver superior electrochemical behaviors. - Abstract: The nickel cobalt manganese oxide (NCMO/CNT) with hierarchical tubular nanoflaky structure is intentionally designed and synthesized via a facile method by using carbon nanotube (CNT) as a backbone template, then the nickel cobalt manganese oxide with nanosheet-like nanotube structure (NCMONST) is synthesized after removed successfully the CNT templates. The morphology, structure and physicochemical properties of the NCMONST samples are characterized by field-emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) and nitrogen adsorption–desorption isotherms. The results reveal that the NCMO shell with a thickness of 0.2 μm grows uniformly on the surface of the CNT with a diameter of 0.1 μm. After calcined NCMO/CNT in air, the mesoporous NCMONST is successfully obtained. The as-prepared NCMONST maintains the tubular and sheets-like structure of NCMO/CNT, and possesses a high specific surface area of 134.1 m{sup 2} g{sup −1}, large pore volume of 0.609 cm{sup 3} g{sup −1} and broad pore-size distribution. The electrochemical results show that the NCMONST exhibits a high specific capacitance of 680 F g{sup −1} at 1 A g{sup −1}, excellent rate capability of 38% at 20 A g{sup −1} and good capacity retention of 88% after 1000 cycles. Therefore, the transition metal oxide with porous structure is a promising electrode candidate for the application of supercapacitors.

  14. Preparation and performance of thin-layered PdAu/ceramic composite membranes

    Energy Technology Data Exchange (ETDEWEB)

    Shi, Lei; Goldbach, Andreas; Zeng, Gaofeng; Xu, Hengyong [Dalian Institute of Chemical Physics, Chinese Academy of Science, Zhongshan Road 457, Dalian 116023 (China)

    2010-05-15

    Preparation of 3-5 {mu}m thick, hydrogen-selective PdAu layers via sequential electroless plating of Pd and Au onto ceramic microfiltration membranes was investigated employing a cyanide-free Au plating bath. The Au deposition rate was strongly dependent on bath temperature and alkalinity reaching an optimum at 333 K and pH 10. Homogenous alloying of the separate metal layers under atmospheric H{sub 2} proved to be a protracted process and required approximately a week at 873 K for a PdAu layer as thin as 3 {mu}m. After 300 h annealing at 823 K the 5 {mu}m thick PdAu layer of a composite membrane still exhibited a Au gradient declining from 7.4 at.% at the top surface to 5.5 at.% at the support interface despite that the H{sub 2} permeation rate had become stable. Nonetheless, the membrane exhibited a very high H{sub 2} permeability of e.g. 1.3 x 10{sup -8} mol m m{sup -2} s{sup -1} Pa{sup -0.5} at 673 K, but it decreased much faster with temperature below 573 K than above, likely due to a change from bulk H diffusion-controlled to H{sub 2} adsorption or desorption-limited transport. The composite membrane withstood cycling between 523 and 723 K in H{sub 2} well showing that differing thermal expansion of the joined metallic and ceramic materials stayed within the tolerance range up to 723 K. (author)

  15. Preparation and performance of fluorescent sensing coating for monitoring corrosion of Al alloy 2024

    Institute of Scientific and Technical Information of China (English)

    LI Song-mei; ZHANG Hong-rui; LIU Jian-hua

    2006-01-01

    A kind of fluorescent sensing coating was prepared for monitoring corrosion of aluminum alloys by incorporating phenylfluorone(PF) into acrylic paint as sensing material. The fluorescent dye PF reacts with aluminum ions on corroded aluminum substrate to occur fluorescence quenching observed in UV light. This paint system is sensitive to underlying corrosion processes through reacting with the Al3+ produced by anodic reaction accompanying corrosion. After a certain time,when the samples of Al alloy 2024 coated with PF-acrylic paint were immersed in 1 mol/L NaCl solution,fluorescence quenching spots can be seen with unaided eyes. With the development of corrosion process,the size of fluorescence quenching spots increases. Active corrosion areas on the sample surface were found under the fluorescence quenching spots by optical microscope. The corrosion areas can be observed more clearly by SEM,and many pits are found. This suggests that the fluorescence quenching spots are the sites of produced Al3+ by the anodic reaction of the local attack of the coated Al alloy substrate in the chloride solution and the corrosion process of the coated Al alloy can be monitored on-line by the sensing coating. The sensitivity of this coating system for detection of anodic reaction associated with corrosion was determined by applying constant charge current and measuring the charge,at which fluorescence quenching is detected in the coating with unaided eyes. Visual observation of coated samples can detect fluorescence change resulting from a charge corresponding to an equivalent hemispherical pit with approximate depth of 50 μm.

  16. One-pot preparation of Ni-graphene hybrids with enhanced catalytic performance

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Guiqiang, E-mail: chengphnu@126.com [College of Information Science and Engineering, Hebei North University, Zhangjiakou 075000, Hebei (China); Wang, Fengli [College of Information Science and Engineering, Hebei North University, Zhangjiakou 075000, Hebei (China); Liu, Fei [Department of Electrical Engineering, Zhangjiakou Vocational College of Technology, Zhangjiakou 075000, Hebei (China); Zhang, Xiao, E-mail: Zhangxiao83690@163.com [College of Information Science and Engineering, Hebei North University, Zhangjiakou 075000, Hebei (China)

    2014-10-15

    Highlights: • Ni-rGO hybrids were synthesized by a microwave-assisted method. • NaBH4 was used as a reducing agent to fabricate Ni-rGO hybrids. • Ni-rGO was used as catalyst for the reduction of p-nitrophenol. • Ni-rGO showed higher catalytic ability than pure Ni nanoparticles. • Ni-rGO showed good recyclability and stability. - Abstract: A facile one-pot method was developed to synthesize magnetic nickel nanoparticles (Ni NPs) decorated on reduced graphene oxide (rGO) with NaHB{sub 4} as a reductant under microwave irradiation. The morphologies and structures of the Ni-rGO hybrids were investigated by electron microscopy, thermal gravimetric analysis, X-ray photoelectron spectroscopy, X-ray diffraction, Raman spectroscopy and magnetic measurements. The results showed that Ni-rGO hybrids composed of the well-dispersed Ni NPs with an average diameter of 12 nm were successfully prepared. To demonstrate one potential application, the catalytic ability of Ni-rGO was evaluated and it was found that Ni-rGO showed much enhanced catalytic ability, good recyclability and stability toward the catalytic reduction of p-nitrophenol to p-aminophenol. The excellent catalytic activity of Ni-rGO hybrids was due possibly to the synergistic effect of Ni NPs and rGO, including the uniform distribution of Ni NPs onto rGO, enhanced electrons separation and transport, as well as the fast adsorption of p-nitrophenol by rGO.

  17. Preparation and Tribological Performance of Novel Organotin Compound as Lubricant Additive

    Institute of Scientific and Technical Information of China (English)

    刘仁德; 陶德华; 赵源; 曹卫国; 张建华; 付尚发

    2004-01-01

    Oil-soluble stannous naphthenate (SN) is synthesized by using naphthenatic acid and SnO. And its molecular structure is confirmed by IR and multielement oil analyzer (MOA). The tribological performances of the organotin as lubricant additive are evaluated with a four-ball friction and wear tester. These experiments indicate that the wear scar diameter (WSD) and friction coefficient are diminished while the load-carrying capability increased by comparison with that of base oil. The elemental composition of the boundary lubricating film is examined by means of Auger electron spectroscopy (AES). Synergistic effect is found in the load-carrying capability of the complex of SN and sulfured olefin. The analytical results of AES indicate that the good performance of stannous naphthenate is attributed to the formation of a boundary lubricating film containing Sn on the rubbed surface.

  18. 30 CFR 250.109 - What documents must I prepare and maintain related to welding?

    Science.gov (United States)

    2010-07-01

    ... related to welding? 250.109 Section 250.109 Mineral Resources MINERALS MANAGEMENT SERVICE, DEPARTMENT OF... Performance Standards § 250.109 What documents must I prepare and maintain related to welding? (a) You must submit a Welding Plan to the District Manager before you begin drilling or production activities on...

  19. Shortage of energy increases profitability of district heating; Energiknapphet gjoer fjernvarme mer loennsomt

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2003-07-01

    Increased demand will cause the price of district heating to increase, but not to the level of the price of electricity. The cheapest heating alternative in Denmark, Norway and Sweden is district heating. In Norway, district heating is developed primarily for commercial buildings and housing cooperatives. Thirty per cent of all buildings under construction are prepared for district heating and the percentage will increase strongly in the coming time. The total net production of district heating in Norway in 2001 was 2000 GWh, which is only a small part of the total potential for district heating.

  20. Electrofusion joining of polyethylene gas pipes: Evaluation of pipe preparation, joining conditions and mechanical performance. Final report, 1990-1995

    Energy Technology Data Exchange (ETDEWEB)

    Grigory, S.C.; Maguire, J.F.; Deviney, M.L.

    1996-04-01

    There were three specific objectives of this research. First, a short time acceptance test for EF (electrofusion) fittings that is fundamentally related to the long time field performance was to be developed that would permit the use of existing lifetime forecasting procedures to quantify joint lifetimes. The second objective was to determine the effects of the various design and installation variables such as power input, heating time, cool-down time, initial pipe-coupler clearance and ambient temperature on the service performance. The third objective was to investigate and quantify the effects of surface preparation and cleanliness on joint integrity. Four final reports have been published to cover the diversified technology developed in this research.

  1. Preparation technology and anti-corrosion performances of black ceramic coatings formed by micro-arc oxidation on aluminum alloys

    Institute of Scientific and Technical Information of China (English)

    CHEN Ling; HAN Jing; YU Shengxue

    2006-01-01

    In order to prepare ornamental and anti-corrosive coating on aluminum alloys, preparation technology of black micro-arc ceramic coatings on Al alloys in silicate based electrolyte was studied.The influence of content of Na2WO4 and combination additive in solution on the performance of black ceramic coatings was studied; the anticorrosion performances of black ceramic coatings were evaluated through whole-immersion test and electrochemical method in 3.5% NaCl solution at different pH value; SEM and XRD were used to analyze the surface morphology and phase constitutes of the black ceramic coatings.Experimental results indicated that, without combination additives, with the increasing of Na2WO4 content in the electrolyte, ceramic coating became darker and thicker, but the color was not black; after adding combination additive, the coating turned to be black; the black ceramic coating was multi-hole form in surface.There was a small quantity of tungsten existing in the black ceramic coating beside α-Al2O3 phase and β-Al2O3 phase.And aluminum alloy with black ceramic coating exhibited excellent anti-corrosion property in acid, basic and neutral 3.5% NaCl solution.

  2. Efficacy of Video-Assisted Instruction on Knowledge and Performance of Dental Students in Access Cavity Preparation

    Science.gov (United States)

    Naseri, Mandana; Shantiaee, Yazdan; Rasekhi, Javid; Zadsirjan, Saeede; Mojtahed Bidabadi, Maryam; Khayat, Akbar

    2016-01-01

    Introduction: The conventional method of teaching endodontics has some drawbacks. Due to the small size of the oral cavity, students cannot closely observe the clinical procedure. Use of new teaching modalities such as the intraoral camera may obviate this problem. This study assessed the effect of video-assisted clinical instruction in dentistry (VACID) on dental student’s knowledge and performance in access cavity preparation during endodontic treatment. Methods and Materials: In this interventional study, twenty six undergraduate students were equally divided into two groups and received instructions on access cavity preparation via conventional demonstration (CD) or VACID using intraoral camera plus conventional demonstration. Students’ knowledge was assessed before and after the demonstration. The scores obtained by students were compared between the two groups. Data were analyzed using the Mann Whitney U test. Results: No significant difference was found between the two groups in knowledge and performance scores of students about pulp chamber removal, under-extension, over-extension, gouging, perforation or finding the main and extra canals. However, use of intraoral camera significantly reduced the number of student visits to instructors for problem solving (P=0.001). Conclusion: VACID is an effective educational method and as efficient as conventional demonstration in endodontics; as a result it can be used in combination with conventional teaching. PMID:27790265

  3. STUDY ON THE PREPARATION AND PERFORMANCES OF P(VAc-MMA) POLYMER ELECTROLYTES FOR LITHIUM ION BATTERY

    Institute of Scientific and Technical Information of China (English)

    Dao-jun Yang; Xiang-kai Fu; Yong-feng Gong

    2008-01-01

    A random copolymer P(VAc-MMA) was synthesized via seeded emulsion copolymerization with vinyl acetate (VAc) and methyl methacrylate (MMA) as monomers, and the polymer electrolytes comprising blend of corresponding copolymer P(VAc-MMA) as a host polymer and LiC104 as a dopant were prepared by solution casting technique. Performances of the synthesized copolymer and prepared polymer membrane and electrolyte were studied by FTIR, XRD, TG, DSC, mechanical testing and AC impedance. According to the study of FTIR and DSC, it was found that P(VAc-MMA) had been formed. XRD indicates that the amorphous nature in copolymer increased with increasing the ratio of VAc in monomers, resulting in expedite migration of ions. The polymer electrolytes based on P(VAc-MMA) possess excellent thermal stability, fine mechanical performance and high ionic conductivity. The maximum ionic conductivity value was found to reach 1.27 × 10-3S·cm-1 at 25℃. The temperature dependence of the polymer electrolyte complexes appeared to obey Arrhenius equation.

  4. The effects of tournament preparation on anthropometric and sport-specific performance measures in youth judo athletes.

    Science.gov (United States)

    Fukuda, David H; Stout, Jeffrey R; Kendall, Kristina L; Smith, Abbie E; Wray, Mandy E; Hetrick, Robert P

    2013-02-01

    The purpose of this study was to characterize the adaptations imposed by 4 weeks of precompetition judo training in youth athletes. It was hypothesized that anthropometric and sport-specific performance would improve during the preparation for a junior national championship event. Twenty youth athletes (mean ± SD; chronological age: 13.1 ± 3.2 years; training age: 5.3 ± 3.5 years; judo experience: 7.8 ± 2.5 hours per week) completed pretesting and posttesting procedures. Child (12 years old; n = 8) and adolescent (13 years old; n = 12) groups were evaluated to determine the anthropometric and sport-specific performance changes caused by 4 weeks of judo training conducted in preparation for the junior national championships. The child group showed an increase in flexibility (11.5%), and the adolescent group showed a decrease in skinfold thickness (-12.2%); increased jumping power (26.7%), force (7.7%), and velocity (19.0%); and improved judo-specific ability (-5.9%), as measured by the Special Judo Fitness Test (SJFT) index. Additionally, the SJFT index for all the study participants was shown to be inversely correlated to handgrip strength (r = -0.681), rope pull performance (r = -0.545), and jump height (r = -0.503). These results support the use of preparatory judo training in the improvement of anthropometric and sport-specific measures in adolescent athletes. Furthermore, the outcomes from this study provide direction for coaches and trainers in their efforts to impact physical performance and judo skills in children and adolescents through precompetition training.

  5. High-performance electrically conductive silver paste prepared by silver-containing precursor

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Jianguo; Cao, Yu; Li, Xiangyou; Wang, Xiaoye; Zeng, Xiaoyan [Huazhong University of Science and Technology, Wuhan National Laboratory for Optoelectronics, College of Optoelectronics Science and Engineering, Wuhan (China)

    2010-09-15

    A high-performance electrically conductive silver paste with no solid particles before drying and/or sintering is developed, in which silver-containing precursor is employed as conductive functional phase. Thermogravimetry analysis, volume electrical resistivity tests and sintering experiments show that the paste with about 14 wt.% silver pristine content is able to achieve the volume electrical resistivity of (2-3) x 10{sup -5} {omega} cm after it is sintered at 220 C. A micro-pen direct-writing process indicates that it is very suitable for the fabrication of high-resolution (25 {mu}m) and high-integration devices and apparatus. (orig.)

  6. High-performance electrically conductive silver paste prepared by silver-containing precursor

    Science.gov (United States)

    Liu, Jianguo; Cao, Yu; Li, Xiangyou; Wang, Xiaoye; Zeng, Xiaoyan

    2010-09-01

    A high-performance electrically conductive silver paste with no solid particles before drying and/or sintering is developed, in which silver-containing precursor is employed as conductive functional phase. Thermogravimetry analysis, volume electrical resistivity tests and sintering experiments show that the paste with about 14 wt.% silver pristine content is able to achieve the volume electrical resistivity of (2-3) ×10-5 Ω cm after it is sintered at 220°C. A micro-pen direct-writing process indicates that it is very suitable for the fabrication of high-resolution (25 μm) and high-integration devices and apparatus.

  7. Preparation of Conducting Poly N-methylaniline Microsphere and Its Antibacterial Performance to Sulfate Reducing Bacteria

    Institute of Scientific and Technical Information of China (English)

    LIU Hongfan; HUANG Li; HUANG Zhuo; QI Gongtai; KEI Nanada; Yutaka Harima

    2008-01-01

    Microspheres of conducting polymers poly N-methylaniline(PNMA)were successfully synthesized through oxidation of N-methylaniline without any template.The average diameter of the M ammonium persulfate in 0.2 M of HCIO4 solution.The size of microspheres can be controlled by changing reaction time and temperature.The acid concentration was critical for the formation of microspheres with smooth surfaces.The excellent antibacterial performance of PNMA in novolac epoxy coating to sulfate reducing bacteria was demonstrated.Moreover,in API media,PNMA inhibited growth of SRB and then reduced the corrosion rate of carbon steel remarkably.

  8. Scheduling Coast Guard District Cutters

    Science.gov (United States)

    1992-09-01

    DESCRIPTION ..... ............ .. 14 D. COSTS, PENALTIES, AND MEASURES OF EFFECTIVENESS 15 iv IV . COMPUTATIONAL EXPERIENCE ............ 19 A. TEST PROBLEMS...used. Using the model of Chapter III, computational performance for a year’s worth of actual data from the First District is presented in Chapter IV ...2G, B-2NY, B-2SAR, C); t - week the cutter assumes the patrol status. COSTO - cost of scheduling cutter i to patrol k; (1 if ship i is available for

  9. Preparation and catalytic performance of ZrO2 - nanographene platelets composites

    Science.gov (United States)

    Kristianto, Y.; Taufik, A.; Saleh, R.

    2016-11-01

    The ZrO2/Nanographene platelets (NGP) composites with different NGP weight percents were successfully synthesized using two-step methods (sol-gel followed by coprecipitation methods). The structural properties of the composites were analyzed using X-Ray Diffraction (XRD), Energy Dispersive X-Ray (EDX), Transmission Electron Microscope (TEM), and Thermalgravimetric Analysis (TGA). The presence of NGP in the composites confirms by the graphitic-like structure in the XRD and layer-like structure in the TEM. Thermal stability of the composites tends to reduce with the incorporation of NGP. The catalytic performances of the composites were evaluated by three catalytic processes. The degradation of methylene blue as a model pollutant by the composites are monitored using UV-Vis Spectroscopy. The result shows that ZrO2 with 10 wt% of NGP exhibits the highest performance for all of three processes. The scavenger experiment shows that hole acts as an active species that play a role in the catalytic process of the composites.

  10. Comparative efficacy of supplementation of phytoconcentrate herbal preparation and synthetic amino acid on broiler performance

    Directory of Open Access Journals (Sweden)

    A. B. Kanduri

    Full Text Available In view to study the role of herbal sources of essential amino acids in improving growth & performance, an experiment was conducted on seventy five day Vencob broiler chicks. Chicks were randomly divided into three groups (n=25, one negative control (T0 and two treatments (T1 & T2. Control group (T0 was offered basal diet deficient in natural or synthetic source of amino acids (choline, methionine, lysine & biotin. Treatment group T1 was fed with basal diet supplemented with polyherbal formulation comprising natural sources (herbs that mimic the activity of amino acids (choline, methionine, lysine & biotin @ 2Kg/tonne of feed while treatment group T2 was fed with basal diet supplemented with combination of synthetic choline chloride (600gm/tonne, synthetic methionine (1kg/tonne, synthetic lysine (1kg/tonne and biotin (150mg/tonne. Growth & performance parameters were recorded at weekly intervals and a metabolic trial for nutrient retention studies was conducted at the end of study. A significant increase in mean body weight gain, mean final body weight, feed efficiency & nutrient retention was observed in both the treated groups as compared to untreated control. The results of group T1 supplemented with herbal sources of amino acids were in confirmation with T2 supplemented with combination of synthetic amino acids suggesting that the polyherbal formula can successfully replace synthetic additives in feed. [Vet. World 2011; 4(9.000: 413-416

  11. Effects of Cycling vs. Running Training on Endurance Performance in Preparation for Inline Speed Skating.

    Science.gov (United States)

    Stangier, Carolin; Abel, Thomas; Hesse, Clemens; Claen, Stephanie; Mierau, Julia; Hollmann, Wildor; Strüder, Heiko K

    2016-06-01

    Winter weather conditions restrict regular sport-specific endurance training in inline speed skating. As a result, this study was designed to compare the effects of cycling and running training programs on inline speed skaters' endurance performance. Sixteen (8 men, 8 women) high-level athletes (mean ± SD 24 ± 8 years) were randomly assigned to 1 of 2 groups (running and cycling). Both groups trained twice a week for 8 weeks, one group on a treadmill and the other on a cycle ergometer. Training intensity and duration was individually calculated (maximal fat oxidation: ∼52% of V[Combining Dot Above]O2peak: 500 kcal per session). Before and after the training intervention, all athletes performed an incremental specific (inline speed skating) and 1 nonspecific (cycling or running) step test according to the group affiliation. In addition to blood lactate concentration, oxygen uptake (V[Combining Dot Above]O2), ventilatory equivalent (VE/V[Combining Dot Above]O2), respiratory exchange ratio (RER), and heart rate were measured. The specific posttest revealed significantly increased absolute V[Combining Dot Above]O2peak values (2.9 ± 0.4, 3.4 ± 0.7, p = 0.01) and submaximal V[Combining Dot Above]O2 values (p ≤ 0.01). VE/V[Combining Dot Above]O2 and RER significantly decreased at maximal (46.6 ± 6.6, 38.5 ± 3.4, p = 0.005; 1.1 ± 0.03, 1.0 ± 0.04, p = 0.001) and submaximal intensities (p ≤ 0.04). None of the analysis revealed a significant group effect (p ≥ 0.15). The results indicate that both cycling vs. running exercise at ∼52% of V[Combining Dot Above]O2peak had a positive effect on the athletes' endurance performance. The increased submaximal V[Combining Dot Above]O2 values indicate a reduction in athletes' inline speed skating technique. Therefore, athletes would benefit from a focus on technique training in the subsequent period.

  12. High performance of solvothermally prepared VO2(B as anode for aqueous rechargeable lithium batteries

    Directory of Open Access Journals (Sweden)

    Milošević Sanja

    2015-01-01

    Full Text Available The VO2 (B was synthesized via a simple solvothermal route at 160oC in ethanol. The initial discharge capacity of VO2 (B anode, in saturated aqueous solution of LiNO3, was 177 mAh g-1 at a current rate of 50 mA g-1. After 50 cycles capacity fade was 4%, but from 20th-50th cycle no capacity drop was observed. The VO2 (B has shown very good cyclability at current rate of even 1000 mA g-1 with initial discharge capacity of 92 mAh g-1. The excellent electrochemical performance of VO2 (B was attributed to the stability of micro-nano structures to repeated intercalation /deintercalation process, very good electronic conductivity as well as the very low charge transfer resistance in the aqueous electrolyte. [Projekat Ministarstva nauke Republike Srbije, br. III45014

  13. A high performance ceria based interdiffusion barrier layer prepared by spin-coating

    DEFF Research Database (Denmark)

    Plonczak, Pawel; Joost, Mario; Hjelm, Johan

    2011-01-01

    A multiple spin-coating deposition procedure of Ce0.9Gd0.1O1.95 (CGO) for application in solid oxide fuel cells (SOFCs) was developed. The thin and dense CGO layer can be employed as a barrier layer between yttria stabilised zirconia (YSZ) electrolyte and a (La, Sr)(Co, Fe)O3 based cathode....... The decomposition of the polymer precursor used in the spin-coating process was studied. The depositions were performed on anode supported half cells. By controlling the sintering temperature between each spin-coating process, dense and crack-free CGO films with a thickness of approximately 1 μm were obtained....... The successive steps of dense layer production was investigated by scanning electron microscopy. X-ray diffraction was employed to monitor the crystal structure of the CGO layer sintered at different temperatures. The described spin coated barrier layer was evaluated using an anode supported cell...

  14. Anticipatory affect during action preparation: evidence from backward compatibility in dual-task performance.

    Science.gov (United States)

    Eder, Andreas B; Pfister, Roland; Dignath, David; Hommel, Bernhard

    2016-07-14

    Upcoming responses in the second of two subsequently performed tasks can speed up compatible responses in the temporally preceding first task. Two experiments extend previous demonstration of such backward compatibility to affective features: responses to affective stimuli were faster in Task 1 when an affectively compatible response effect was anticipated for Task 2. This emotional backward-compatibility effect demonstrates that representations of the affective consequences of the Task 2 response were activated before the selection of a response in Task 1 was completed. This finding is problematic for the assumption of a serial stimulus-response translation stage. It also shows that the affective consequence of a response is anticipated during, and has an impact on stimulus-response translation, which implies that action planning considers codes representing and predicting the emotional consequences of actions. Implications for the control of emotional actions are discussed.

  15. Kinetics of Formic Acid-autocatalyzed Preparation of Performic Acid in Aqueous Phase

    Institute of Scientific and Technical Information of China (English)

    孙晓英; 赵雪冰; 杜伟; 刘德华

    2011-01-01

    Performic acid (PFA) is an oxidant used in chemical processing, synthesis and bleaching. The macro kinetic models of synthesis, hydrolysis and decomposition of PFA were investigated via formic acid-autocatalyzed reaction. It was found that the intrinsic activation energies of PFA synthesis and hydrolysis were 75.2 kJ·mol^-1 and 40.4 kJ·mol^-1 respectively. The observed activation energy of PFA decomposition was 95.4 kJ·mol^-1. The experi-mental results indicated that the decomposition of PFA was liable to occur even at the ambient temperature. Both the spontaneous decomposition and the radical-introduced decomposition contributed to the decomposition of PFA.

  16. Preparing for the real world. Program helps rehabilitation patients perform everyday tasks.

    Science.gov (United States)

    Parthemore, W

    1994-11-01

    St. Francis Health Care Centre in Green Springs, OH, decided in 1991 to enlist local merchants in a program in rehabilitative medicine. The program, named for Green Springs's main street, is "Broadway: A Route Home." Broadway is a program for persons who, because of severe illness or injury, require extended rehabilitation. Along with care for continuing physical or cognitive problems, such patients often need help in performing tasks--buying groceries, cashing a check, renting a video--that most people take for granted. Under the Broadway program patients can practice these tasks safely in shops, restaurants, and theaters in Green Springs and other nearby communities. Later, escorted by therapists, some patients journey to larger cities and, finally, to their own communities, to exercise everyday skills.

  17. The preparation of conductive nano-LiFePO{sub 4}/PAS and its electrochemical performance

    Energy Technology Data Exchange (ETDEWEB)

    Liu Jing [Institute of Functional Materials, Department of Chemistry, Northeast Normal University, Changchun, Jilin 130024 (China); LIB Engineering Laboratory, Materials Science and Technology Center, Changchun, Jilin 130024 (China); Liu Fukuan [Budget Quota Administrative Center, Gudao Production Plant of Shengli Oil Field, Sinopec Corp., Dongying, Shandong 257231 (China); Yang Guiling; Zhang Xianfa; Wang Jiawei [Institute of Functional Materials, Department of Chemistry, Northeast Normal University, Changchun, Jilin 130024 (China); Wang Rongshun, E-mail: wangrs@nenu.edu.c [Institute of Functional Materials, Department of Chemistry, Northeast Normal University, Changchun, Jilin 130024 (China); LIB Engineering Laboratory, Materials Science and Technology Center, Changchun, Jilin 130024 (China)

    2010-01-01

    A simple and effective method has been developed to synthesize a nano-sized LiFePO{sub 4}/PAS (polyacenic semiconductor) composite. The LiFePO{sub 4} particles coated and connected by PAS are uniformly distributed in the range of 50-80 nm. The electronic conductivity of this material is as high as 1.2 x 10{sup -1} S/cm due to the conductive network of PAS. In comparison with the micro-LiFePO{sub 4}/PAS, the nano-LiFePO{sub 4}/PAS exhibits much better rate performance. At the 12-min charge-discharge rate, the power and energy densities of the nano-LiFePO{sub 4}/PAS are shown as 2063 W/kg and 412 Wh/kg, which are much higher than those of the micro-LiFePO{sub 4}/PAS (1600 W/kg and 320 Wh/kg). It is especially notable that the nano-LiFePO{sub 4}/PAS cathode without adding Super P shows similar electrochemical behaviors with the cathode adding Super P at all C-rates. Thus, such cathode without adding Super P will enlarge both the volume energy density and weight energy density of batteries. In addition, this cathode exhibits an excellent long-term cyclability, retaining over 95.4% of its original discharge capacity beyond 500 cycles at 0.2C rate. These favorable electrochemical performances should be attributed to its nanometric particle size and the high electronic conductivity.

  18. Procedures for selecting and buying district heating equipment. Sofia district heating. Final report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-11-01

    The aim of this Final Report, prepared for the project `Procedures for Selecting and Buying DistRict Heating Equipment - Sofia District Heating Company`, is to establish an overview of the activities accomplished, the outputs delivered and the general experience gained as a result of the project. The main objective of the project is to enable Sofia District Heating Company to prepare specifications and tender documents, identify possible suppliers, evaluate offers, etc. in connection with purchase of district heating equipment. This objective has been reached by using rehabilitation of sub-stations as an example requested by Sofia DH. The project was originally planned to be finalized end of 1995, but due to the extensions of the scope of work, the project has been prolonged until end 1997. The following main activities were accomplished: Preparation of a detailed work plan; Collection of background information; Discussion and advice about technical specifications and tender documents for sub-station rehabilitation; Input to terms of reference for a master plan study; Input to technical specification for heat meters; Collection of ideas for topics and examples related to dissemination of information to consumers about matters related to district heating consumption. (EG)

  19. Assessing the Distribution of Fiscal and Personnel Resources across Schools. A Report Prepared for Los Angeles Unified School District. SSFR Research Report #01 (LAUSD). Strategic School Funding for Results (SSFR)

    Science.gov (United States)

    Chambers, Jay G.; Levin, Jesse; Brodziak, Iliana; Chan, Derek

    2010-01-01

    Using fiscal data provided by the finance office of the school district, and personnel data obtained from the California Basic Education Data System maintained by the California Department of Education (CDE), the authors present analyses to provide a foundation for local policymakers that may be used to assess whether there are inequities in the…

  20. Synthesis of nitrogen doped microporous carbons prepared by activation-free method and their high electrochemical performance

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Ki-Seok [Department of Chemistry, Inha University, Incheon 402-751 (Korea, Republic of); Park, Soo-Jin, E-mail: sjpark@inha.ac.kr [Department of Chemistry, Inha University, Incheon 402-751 (Korea, Republic of)

    2011-11-30

    Graphical abstract: This describes the increase of specific capacitance in hybrid electrodes as a function of melamine content. Display Omitted Highlights: > For N-enriched hybrid carbons, co-precursors, PVDF/melamine composites, were used. > Microporous carbons were formed by only carbonization without chemical activation. > The nitrogen content of microporous carbons was controlled by melamine content. > N-doped carbons showed higher specific capacitance compared to microporous carbons. > It was attributed to the easy electron transfer and pseudocapacitance. - Abstract: Nitrogen-doped microporous carbons (N-MCs) were prepared by the carbonization of the polyvinylidene fluoride (PVDF)/melamine mixture without chemical activation. The electrochemical performance of the N-MCs was investigated as a function of PVDF/melamine ratio. It was found that, without additional activation, the N-MCs had a high specific surface area (greater than 560 m{sup 2}/g) because of the micropore formation by the release of fluorine groups. In addition, although the specific surface area decreased, nitrogen groups were increased with increasing melamine content, leading to an enhanced electrochemical performance. Indeed, the N-MCs showed a better electrochemical performance than that of microporous carbons (MCs) prepared by PVDF alone, and the highest specific capacitance (310 F/g) was obtained at a current density of 0.5 A/g, as compared to a value of 248 F/g for MCs. These results indicate that the microporous features of N-MC lead to feasible ion transfer during charge/discharge duration and the presence of nitrogen groups as strong electron donor on the N-MC electrode in electrolyte could provide a pseudocapacitance by the redox reaction.

  1. SAPO-34 Membranes for N-2/CH4 separation: Preparation, characterization, separation performance and economic evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Li, SG; Zong, ZW; Zhou, SJ; Huang, Y; Song, ZN; Feng, XH; Zhou, RF; Meyer, HS; Yu, M; Carreon, MA

    2015-08-01

    SAPO-34 membranes were synthesized by several routes towards N-2/CH4 separation. Membrane synthesis parameters including water content in the gel, crystallization time, support pore size, and aluminum source were investigated. High performance N-2-selective membranes were obtained on 100-nm-pore alumina tubes by using Al(i-C3H7O)(3) as aluminum source with a crystallization time of 6 h. These membranes separated N-2 from CH, with N-2 permeance as high as 500 GPU with separation selectivity of 8 at 24 degrees C. for a 50/50 N-2/CH4 mixture. Nitrogen and CH, adsorption isotherms were measured on SAPO-34 crystals. The N-2 and CH, heats of adsorption were 11 and 15 kJ/mol, respectively, which lead to a preferential adsorption of CE-H-4 over N-2 in the N-2/CH4 mixture. Despite this, the SAPO-34 membranes were selective for N-2 over CH4 in the mixture because N-2 diffuses much faster than CH4 and differences in diffusivity played a more critical role than the competitive adsorption. Preliminary economic evaluation indicates that the required N-2/CH4 selectivity would be 15 in order to maintain a CH4 loss below 10%. For small nitrogen-contaminated gas wells, our current SAPO-34 membranes have potential to compete with the benchmark technology cryogenic distillation for N-2 rejection. (C) 2015 Elsevier B.V. All rights reserved,

  2. Preparation and laser performance of Nd-doped yttrium lanthanum oxide transparent ceramic

    Science.gov (United States)

    Yang, Qiuhong; Lu, Shenzhou; Zhang, Bin; Zhang, Haojia; Zhou, Jun; Yuan, Zhijun; Qi, Yunfeng; Lou, Qihong

    2011-03-01

    1.5 at.% Nd:Y 1.8La 0.2O 3 transparent ceramic was fabricated by a solid-state reaction method and sintered at 1650-1700 °C for 40-50 h under H 2 atmosphere. The spectroscopic properties were investigated at room temperature. The transparent ceramic has excellent spectroscopic properties, with the absorption cross section of 1.50 × 10 -20 cm 2 and broad full width at half maximum (FWHM) of about 8 nm at LD wavelength 806 nm, the emission cross section of 2.03 × 10 -20 cm 2 at 1079 nm, and the decay lifetime of 200 μs. Laser performance was carried out using an uncoated Nd:Y 1.8La 0.2O 3 ceramic plate under laser diode end-pumping without any water cooling device. The room temperature thermal conductivity of this ceramic is 6.20 W/mK. For Nd:Y 1.8La 0.2O 3 ceramic laser, a maximum output power of 62 mW was obtained at 1079 nm under a 808 nm diode pump.

  3. Preparation and electrochemical performance of sulfur-alumina cathode material for lithium-sulfur batteries

    Energy Technology Data Exchange (ETDEWEB)

    Dong, Kang [Faculty of Material Science and Chemistry, China University of Geosciences, 388 Lumo Road, 430074 Wuhan (China); Wang, Shengping, E-mail: spwang@cug.edu.cn [Faculty of Material Science and Chemistry, China University of Geosciences, 388 Lumo Road, 430074 Wuhan (China); Zhang, Hanyu; Wu, Jinping [Faculty of Material Science and Chemistry, China University of Geosciences, 388 Lumo Road, 430074 Wuhan (China)

    2013-06-01

    Highlights: ► Micron-sized alumina was synthesized as adsorbent for lithium-sulfur batteries. ► Sulfur-alumina material was synthesized via crystallizing nucleation. ► The Al{sub 2}O{sub 3} can provide surface area for the deposition of Li{sub 2}S and Li{sub 2}S{sub 2}. ► The discharge capacity of the battery is improved during the first several cycles. - Abstract: Nano-sized sulfur particles exhibiting good adhesion with conducting acetylene black and alumina composite materials were synthesized by means of an evaporated solvent and a concentrated crystallization method for use as the cathodes of lithium-sulfur batteries. The composites were characterized and examined by X-ray diffraction, environmental scanning electron microscopy and electrochemical methods, such as cyclic voltammetry, electrical impedance spectroscopy and charge–discharge tests. Micron-sized flaky alumina was employed as an adsorbent for the cathode material. The initial discharge capacity of the cathode with the added alumina was 1171 mAh g{sup −1}, and the remaining capacity was 585 mAh g{sup −1} after 50 cycles at 0.25 mA cm{sup −2}. Compared with bare sulfur electrodes, the electrodes containing alumina showed an obviously superior cycle performance, confirming that alumina can contribute to reducing the dissolution of polysulfides into electrolytes during the sulfur charge–discharge process.

  4. The Facile Hydrothermal Preparation of Orthorhombic WO3 With (001) Facet and Its Photocatalytic Performance.

    Science.gov (United States)

    Deng, Xiaoyan; Dou, Jinbiao; Li, Fenfen; Gao, Hongtao; Liu, Guangjun

    2015-12-01

    The orthorhombic WO3 nanoplates with (001) facet were fabricated via a facile hydrothermal process, using HBF4 as the acid source. The products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM) and UV-vis diffused reflectance spectroscopy (DRS), respectively. It indicated that the obtained product was orthorhombic WO3 (JCPDS No. 20-1324). And the energy gap was estimated to be 2.52 eV by the intersection point of the tangent of the absorption edge and the baseline. It was affirmed that WO3 crystalline grew along the (001) direction, indicating the product was exposed with (001) facet. The photocatalytic activity of (001) WO3 nanoplates was investigated on the degradation of Rhodamine B (RhB). It demonstrated that photocatalysts exhibited obvious photocatalytic performance under visible light irradiation. The degradation rate of RhB with the typical product reached 95% after being irradiated for 5 h. It indicated that the photocatalytic efficiency of WO3 could be improved by controlling the crystal growth and its morphology.

  5. Preparation of High Performance Foamed Concrete from Cement, Sand and Mineral Admixtures

    Institute of Scientific and Technical Information of China (English)

    PAN Zhihua; Fujiwara Hiromi; Wee Tionghuan

    2007-01-01

    The titled high performance foamed concrete was developed from Portland cement, ultra fine granulated blast-furnace slag, pulverized fly ash and condensed silica fume by means of pre-foaming process. The resultant foamed concrete presents its thermal conductivity of about 0.16-0.75 W/(m·℃) and 28 d compressive strength of about 1.1-23.7 MPa when its mix proportion varies in the range of cement content 280 kg-650 kg/m3, fly ash 42-97 kg/m3, slag 64-146 kg/m3, silica fume 34-78 kg/m3, and sand 0-920 kg/m3. The compressive strength of the foamed concrete with oven dried bulk density of 1500 kg/m3 in appropriate mix proportion and with small amount of superplasticizer reached as high as 44.1 MPa. Meanwhile, the fresh foamed concrete behaves like an excellent flow-ability, therefore, is especially suitable for the application in case of massive foamed concrete casting in situ and in the case of filling casting into large volume underground irregular voids, except for pre-casting of building components like blocks, bricks, and wall panels.

  6. Preparation of high performance ceramic tiles using waste tile granules and ceramic polishing powder

    Institute of Scientific and Technical Information of China (English)

    WANG Gong-xun; SU Da-gen

    2008-01-01

    This paper presents an innovative approach to reusing waste tile granules (TG) and ceramic polishing powder (PP) to produce high performance ceramic tiles. We studied formulations each with a TG mass fraction of 25.0% and a different PP mass fraction between 1.0% and 7.0%. The formulations included a small amount of borax additive of a mass fracton between 0.2%and 1.2%. The effects of these industrial by-products on compressive strength, water absorption and microstructure of the new ceramic tiles were investigated. The results indicate that the compressive strength decreases and water absorption increases when TG with a mass fraction of 25.0% are added. Improvement of the compressive strength may be achieved when TG (up to 25.0%)and PP (up to 2.0%) are both used at the same time. In particular, the compressive strength improvement can be maximized and water absorption reduced when a borax additive of up to 0.5% is used as a flux. Scanning electron microscopy reveals that a certain amount of fine PP granules and a high content of fluxing oxides from borax avail the formation of glassy phase that fills up the pores in the new ceramic tiles, resulting in a dense product with high compressive strength and low water absorption.

  7. Assessment of midwifery student preparation for performing the role of breast cancer educator.

    Science.gov (United States)

    Bien, Agnieszka Maria; Korzynska-Pietas, Magdalena; Iwanowicz-Palus, Grazyna Jolanta

    2014-01-01

    Our research project aimed at presenting midwifery student self-assessment of performing the role of breast cancer prevention educator. Investigations were carried out in 2011 at the Medical University of Lublin in Poland, and Katolieke Hogeschool of Kortrijk in Belgium, after obtaining approval of the ethical committee of Polish Midwives Association (III/EC/2011/PMA). The project involved a total of 155 midwifery students, made up of 95 from Poland, and 60 from Belgium. Relations between opposing characteristics were tested with Chi-square (x2) test for independent traits. To assess the dependence relation between the examined variables Pearson's corrected coefficient was used. Data base and statistics were carried out with computer software STATISTICA 9.0 (StatSoftPoland). Student knowledge on prevention against breast cancer was unsatisfactory.The students place of residence determined their self-estimation of personal knowledge of breast cancer prevention and diagnosing methods to assess the incidence of the disease, this knowledge being better with the students of Lublin. Better self-estimation in the students of Lublin of their personal knowledge on factors rising the risk of breast cancer, such as alimentation method, application of oral contraceptives and breast feeding was found than in Belgian students.

  8. Performance of ultrasonic – Treated nano-zeolites employed in the preparation of dimethyl ether

    Directory of Open Access Journals (Sweden)

    Sanaa M. Solyman

    2013-06-01

    Full Text Available Catalytic dehydration of methanol to dimethyl ether was carried out over nano-zeolites and their modified samples via ultrasonic technique. Parent H-Beta and Parent H-Mordenite zeolites are used as synthesized and after sonication. H-Mordenite sonicated for 20 and 120 min whereas H-Beta sonicated for 20 min only. The reaction temperature was varied between 100 and 225 °C at three different contact times. The different catalyst samples were characterized using: XRD, FTIR, TEM, SEM and NH3-TPD techniques. The results revealed that sonication of parent zeolite samples affects on the unit cell dimensions and their crystal size. FTIR-spectroscopic analysis indicated that sonication may decrease the pore opening and cause framework structure defects. TEM and SEM micrographs showed that sonication broke-up and re-ordered zeolite crystals with longer time resulted in a different morphology relative to parents and also change the particle size. Sonicated samples have a good performance in methanol dehydration with complete conversion and complete selectivity to dimethyl ether at lower temperature relative to the corresponding parent zeolites. TPD results indicated that the concentration of strong acid sites decreased in sonicated H-Mordenite samples leading to an increase of their catalytic activity and the selectivity to DME. On the other hand, ultrasonic treatment of H-Beta sample decreased its catalytic activity.

  9. Preparation and Molten Salt as Performances of Room Electrolyte carbon Capacitor Based on Trifluoroacetamide n CarbonLiPF6 and

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    A novel room moRen salt with an eutectic temperature of about -62℃ is prepared using LiPF6 and trifluoroacetamide as precursors. And then its performance is evaluated in carbon-carbon electrochemical double layerdifferent molar ratios are characterized and then the liquid-solid phase diagram is presented. The electrochemical performance tests show that the as-prepared LiPF6/trifluoroacetamide molten salt is a promising electrolyte candidate for carboncarbon EDLCs.

  10. Tribological performance of an H-DLC coating prepared by PECVD

    Science.gov (United States)

    Solis, J.; Zhao, H.; Wang, C.; Verduzco, J. A.; Bueno, A. S.; Neville, A.

    2016-10-01

    Carbon-based coatings are of wide interest due to their application in machine elements subjected to continuous contact where fluid lubricant films are not permitted. This paper describes the tribological performance under dry conditions of duplex layered H-DLC coating sequentially deposited by microwave excited plasma enhanced chemical vapour deposition on AISI 52100 steel. The architecture of the coating comprised Cr, WC, and DLC (a-C:H) with a total thickness of 2.8 μm and compressive residual stress very close to 1 GPa. Surface hardness was approximately 22 GPa and its reduced elastic modulus around 180 GPa. Scratch tests indicated a well adhered coating achieving a critical load of 80 N. The effect of normal load on the friction and wear behaviours were investigated with steel pins sliding against the actual coating under dry conditions at room temperature (20 ± 2 °C) and 35-50% RH. The results show that coefficient of friction of the coating decreased from 0.21 to 0.13 values with the increase in the applied loads (10-50 N). Specific wear rates of the surface coating also decrease with the increase in the same range of applied loads. Maximum and minimum values were 14 × 10-8 and 5.5 × 10-8 mm-3/N m, respectively. Through Raman spectroscopy and electron microscopy it was confirmed the carbon-carbon contact, due to the tribolayer formation on the wear scars of the coating and pin. In order to further corroborate the experimental observations regarding the graphitisation behaviour, the existing mathematical relationships to determine the graphitisation temperature of the coating/steel contact as well as the flash temperature were used.

  11. Superior mechanical performance of highly porous, anisotropic nanocellulose-montmorillonite aerogels prepared by freeze casting.

    Science.gov (United States)

    Donius, Amalie E; Liu, Andong; Berglund, Lars A; Wegst, Ulrike G K

    2014-09-01

    Directionally solidified nanofibrillated cellulose (NFC)-sodium-montmorillonite (MMT) composite aerogels with a honeycomb-like pore structure were compared with non-directionally frozen aerogels with equiaxed pore structure and identical composition and found to have superior functionalities. To explore structure-property correlations, three different aerogel compositions of 3wt% MMT, and 0.4wt%, 0.8wt%, and 1.2wt% NFC, respectively, were tested. Young׳s modulus, compressive strength and toughness were found to increase with increasing NFC content for both architectures. The modulus increased from 25.8kPa to 386kPa for the isotropic and from 2.13MPa to 3.86MPa for the anisotropic aerogels, the compressive yield strength increased from 3.3kPa to 18.0kPa for the isotropic and from 32.3kPa to 52.5kPa for the anisotropic aerogels, and the toughness increased from 6.3kJ/m(3) to 24.1kJ/m(3) for the isotropic and from 22.9kJ/m(3) to 46.2kJ/m(3) for the anisotropic aerogels. The great range of properties, which can be achieved through compositional as well as architectural variations, makes these aerogels highly attractive for a large range of applications, for which either a specific composition, or a particular pore morphology, or both are required. Finally, because NFC is flammable, gasification experiments were performed, which revealed that the inclusion of MMT increased the heat endurance and shape retention functions of the aerogels dramatically up to 800°C while the mechanical properties were retained up to 300°C.

  12. Improvement of proton exchange membrane fuel cell electrical performance by optimization of operating parameters and electrodes preparation

    Energy Technology Data Exchange (ETDEWEB)

    Kadjo, A.J.-J.; Garnier, J.-P.; Martemianov, S. [Laboratoire d' Etudes Thermiques, UMR6608, ESIP-Universite de Poitiers, CNRS, Poitiers F-86022 (France); Brault, P.; Caillard, A. [Groupe de Recherche sur l' Energetique des Milieux Ionises, UMR6606 Universite d' Orleans, CNRS Polytech' Orleans BP6744, F-45067 Orleans Cedex 2 (France); Coutanceau, C. [Laboratoire de Catalyse en Chimie Organique, UMR6503 Universite de Poitiers, CNRS, Poitiers F-86022 (France)

    2007-10-25

    The effect of operating parameters (cell temperature, humidifiers temperature, gases flows and pressures) on the performance of a 25 cm{sup 2} surface area fuel cell is performed. After optimization, a homemade MEA fitted with electrodes prepared via the colloidal route leads to achieve reproducibly maximum power densities higher than 1.2 W cm{sup -2} with a total catalyst loading of 0.7 mg{sub Pt} cm{sup -2} (corresponding to 1.7kW g{sub Pt}{sup -1}). This electrical performance is higher to that obtained with a commercial MEA provided by fuel cell store (total platinum loading of 1.2 mg cm{sup -2} and power density close to 1 W cm{sup -2}, corresponding to 0.75kW g{sub Pt}{sup -1}). Based on this experience, two different homemade MEAs are tested under optimal operating conditions and compared to the commercial one. The final goal is to decrease significantly the platinum loading preserving at least equivalent PEMFC electrical performance. The method of catalyst deposition by plasma sputtering is used to further decrease the total catalyst loading down to 0.45 mg{sub Pt} cm{sup -2}. Very interesting performances (close to 0.7 W cm{sup -2}) were obtained with this low-platinum loading MEA (corresponding to 1.6kW g{sub Pt}{sup -1}). However, it was shown that the decrease of the platinum loading in the cathode from 0.35 to 0.1 mg cm{sup -2} affects the kinetics of oxygen reduction (exchange current density j{sub 0} and Tafel slope b) and the resistance of the cell R, and hence the cell electrical performance. (author)

  13. Tribological performance of an H-DLC coating prepared by PECVD

    Energy Technology Data Exchange (ETDEWEB)

    Solis, J., E-mail: jsolis@ittla.edu.mx [IFS, University of Leeds, School of Mechanical Engineering, Leeds, LS2 9JT (United Kingdom); SEP/SES/TecNM/IT de Tlalnepantla, DEPI-Mechanical Engineering, 54070, Edo. Méx. (Mexico); Zhao, H.; Wang, C. [IFS, University of Leeds, School of Mechanical Engineering, Leeds, LS2 9JT (United Kingdom); Verduzco, J.A. [Instituto de Investigación en Metalurgia y Materiales, UMSNH, P.O. Box 888, 58000, Morelia, Mich. (Mexico); Bueno, A.S. [IFS, University of Leeds, School of Mechanical Engineering, Leeds, LS2 9JT (United Kingdom); Mechanical Engineering Department, Universidade Federal de São João Del Rei, 170 Praça Frei Orlando, 36307-352 São João Del Rei (Brazil); Neville, A. [IFS, University of Leeds, School of Mechanical Engineering, Leeds, LS2 9JT (United Kingdom)

    2016-10-15

    Highlights: • Duplex hydrogenated Diamond-like Carbon was produced and characterised. • Friction and wear under dry condition of H-DLC/steel tribopair was assessed. • Adhesive strength of the coating was 80N after the scratch tests under dry condition. • Maximum and minimum values of average coefficient of friction were 0.21 and 0.13. • A protective transferred layer on the counterpart produced a carbon-carbon contact. - Abstract: Carbon-based coatings are of wide interest due to their application in machine elements subjected to continuous contact where fluid lubricant films are not permitted. This paper describes the tribological performance under dry conditions of duplex layered H-DLC coating sequentially deposited by microwave excited plasma enhanced chemical vapour deposition on AISI 52100 steel. The architecture of the coating comprised Cr, WC, and DLC (a-C:H) with a total thickness of 2.8 μm and compressive residual stress very close to 1 GPa. Surface hardness was approximately 22 GPa and its reduced elastic modulus around 180 GPa. Scratch tests indicated a well adhered coating achieving a critical load of 80 N. The effect of normal load on the friction and wear behaviours were investigated with steel pins sliding against the actual coating under dry conditions at room temperature (20 ± 2 °C) and 35–50% RH. The results show that coefficient of friction of the coating decreased from 0.21 to 0.13 values with the increase in the applied loads (10–50 N). Specific wear rates of the surface coating also decrease with the increase in the same range of applied loads. Maximum and minimum values were 14 × 10{sup −8} and 5.5 × 10{sup −8} mm{sup −3}/N m, respectively. Through Raman spectroscopy and electron microscopy it was confirmed the carbon-carbon contact, due to the tribolayer formation on the wear scars of the coating and pin. In order to further corroborate the experimental observations regarding the graphitisation behaviour, the

  14. Preparation of hollow microspheres of Ce3+ doped NiCo ferrite with high microwave absorbing performance

    Science.gov (United States)

    Duan, Hong-zhen; Zhou, Fang-ling; Cheng, Xia; Chen, Guo-hong; Li, Qiao-ling

    2017-02-01

    Hollow microspheres of Ce3+ doped NiCo-ferrites were synthesized by template-based-deposition and surface reaction method with carbon sphere as the template. The phase structure, morphology, magnetic properties and wave absorbing properties of the sample were characterized by X-ray powder diffraction(XRD), Scanning electronic microscopy(SEM), Vibration sample magnetometer (VSM) and a network vector analyzer (NVA), respectively. The results indicated that the particle size of the carbon sphere sample prepared by hydrothermal method was about 0.5 μm and the particle size of the Ni0.5Co0.5Fe2O4 sample prepared by template-based method was about 300 nm. The influence of the amount of rare earth element on the magnetic and absorbing properties of sample was studied. The saturation magnetization and coercivity decreased gradually with the increase of the content of Ce. When the content of Ce was 0.02, the maximal saturation magnetization value and coercivity was 75.72 emu•g-1 and 789.88 Oe, respectively. The associated ferrite hollow spheres have good absorbing performance, and the return loss value was -18.8 dB at 5500 MHz.

  15. Assessment of stability of ketamine-xylazine preparations with or without acepromazine using high performance liquid chromatography-mass spectrometry

    Science.gov (United States)

    Dodelet-Devillers, Aurore; Zullian, Chiara; Vachon, Pascal; Beaudry, Francis

    2016-01-01

    The objective of this study was to evaluate the stability of 3 distinct preparations of ketamine and xylazine, with or without acepromazine, stored at room temperature or at 4°C for 1, 2, and 3 mo. Drug concentrations were compared to fresh solutions, using a high performance liquid chromatography-mass spectrometry/selected-ion monitoring (HPLC-MS/SIM) assay. The concentrations of ketamine and xylazine, diluted in physiological saline, did not change over time at room temperature or at 4°C. However, acepromazine concentrations decreased over time when stored at room temperature. In contrast, undiluted ketamine-xylazine preparations gradually decreased in concentration when stored at room temperature. All of the drug concentrations remained above 90% of their original concentration when stored at 4°C. In conclusion, when diluted in physiological saline, ketamine-xylazine cocktails can be stored for 3 mo, whereas undiluted cocktails can lose efficacy over 3 mo at room temperature. Storage at 4°C could preserve drug stability. PMID:26733737

  16. Effect of the catalytic ink preparation method on the performance of high temperature polymer electrolyte membrane fuel cells

    Science.gov (United States)

    Lobato, J.; Rodrigo, M. A.; Linares, J. J.; Scott, K.

    Two methods of preparation of the membrane-electrode-assemblies based on polybenzimidazole membranes have been studied for high temperatures PEMFCs. One is called the "colloidal method" (using acetone as solvent), and the other is the "solution method" (using dimethylacetamide as solvent). Physical property studies (SEM micrographs and pore size distribution) and electrochemical analyses in half-cell (Electrochemical Impedance Spectroscopy, Polarization Curves for Oxygen Reduction and Cyclic Voltammetry) were carried out to characterise the structural and electrochemical behaviour of both methods. Finally, a cell performance investigation, using electrodes prepared by both methods was carried out at three different temperatures (125, 150, and 175 °C), in a single PEMFC setup. A better behaviour was obtained for the "solution method" at the two highest temperatures at intermediate current densities, whereas at 125 °C the best results were obtained with the "colloidal method" in all the current densities ranges. A discussion of the behaviours observed with the different characterisation techniques is made.

  17. Effect of the catalytic ink preparation method on the performance of high temperature polymer electrolyte membrane fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Lobato, J.; Rodrigo, M.A.; Linares, J.J. [Chemical Engineering Department, University of Castilla-La Mancha, Campus Universitario s/n, 13004 Ciudad Real (Spain); Scott, K. [School of Chemical Engineering and Advanced Materials, University of Newcastle upon Tyne, Merz Court NE1 7RU (United Kingdom)

    2006-06-19

    Two methods of preparation of the membrane-electrode-assemblies based on polybenzimidazole membranes have been studied for high temperatures PEMFCs. One is called the 'colloidal method' (using acetone as solvent), and the other is the 'solution method' (using dimethylacetamide as solvent). Physical property studies (SEM micrographs and pore size distribution) and electrochemical analyses in half-cell (Electrochemical Impedance Spectroscopy, Polarization Curves for Oxygen Reduction and Cyclic Voltammetry) were carried out to characterise the structural and electrochemical behaviour of both methods. Finally, a cell performance investigation, using electrodes prepared by both methods was carried out at three different temperatures (125, 150, and 175{sup o}C), in a single PEMFC setup. A better behaviour was obtained for the 'solution method' at the two highest temperatures at intermediate current densities, whereas at 125{sup o}C the best results were obtained with the 'colloidal method' in all the current densities ranges. A discussion of the behaviours observed with the different characterisation techniques is made. (author)

  18. The Preparation and Performances of Self-Dispersed Nanomicron Emulsified Wax Solid Lubricant Ewax for Drilling Fluids

    Directory of Open Access Journals (Sweden)

    Feng-shan Zhou

    2014-01-01

    Full Text Available An oil-in-water nanomicron wax emulsion with oil phase content 45 wt% was prepared by using the emulsifying method of surfactant-in-oil. The optimum prepared condition is 85°C, 20 min, and 5 wt% complex emulsifiers. Then the abovementioned nanomicron emulsifying wax was immersed into a special water-soluble polymer in a certain percentage by the semidry technology. At last, a solidified self-dispersed nanomicron emulsified wax named as Ewax, a kind of solid lubricant for water based drilling fluid, was obtained after dried in the special soluble polymer containing emulsifying wax in low temperature. It is shown that the adhesion coefficient reduced rate (ΔKf is 73.5% and the extreme pressure (E-P friction coefficient reduced rate (Δf is 77.6% when the produced Ewax sample was added to fresh water based drilling fluid at dosage 1.0 wt%. In comparison with other normal similar liquid products, Ewax not only has better performances of lubrication, filtration loss control property, heat resistance, and tolerance to salt and is environmentally friendly, but also can solve the problems of freezing in the winter and poor storage stability of liquid wax emulsion in oilfield applications.

  19. High performance screen-printed electrodes prepared by a green solvent approach for lithium-ion batteries

    Science.gov (United States)

    Gören, A.; Mendes, J.; Rodrigues, H. M.; Sousa, R. E.; Oliveira, J.; Hilliou, L.; Costa, C. M.; Silva, M. M.; Lanceros-Méndez, S.

    2016-12-01

    New inks based on lithium iron phosphate and graphite for cathode and anode, respectively, were developed for printable lithium-ion batteries using the "green solvent" N,N‧-dimethylpropyleneurea (DMPU) and poly(vinylidene fluoride), PVDF, as a binder. The results were compared with the ones from inks developed with the conventionally used solvent N-methyl-2-pyrrolidone, NMP. The rheological properties of the PVDF/DMPU binder solution shows a more pronounced shear thinning behavior than the PVDF/NMP solution. Cathode inks prepared with 2.25 mL and 2.50 mL of DMPU for 1 g of electrode mass show an apparent viscosity of 3 Pa s and 2 Pa s for a shear rate of 100 s-1, respectively, being therefore processable by screen-printing or doctor blade techniques. The electrodes prepared with DMPU and processed by screen-printing show a capacity of 52 mAh g-1 at 2C for the cathode and 349 mAh g-1 at C/5 for the anode, after 45 charge-discharge cycles. The electrochemical performance of both electrodes was evaluated in a full-cell and after 9 cycles, the discharge capacity value is 81 mAh g-1, showing a discharge capacity retention of 64%. The new inks presented in this work are thus suitable for the development of printed batteries and represent a step forward towards more environmental friendly processes.

  20. High-performance K-band GaAs power field-effect transistors prepared by molecular beam epitaxy

    Science.gov (United States)

    Saunier, P.; Shih, H. D.

    1983-01-01

    The maturity of the molecular beam epitaxy (MBE) technique for preparing device quality GaAs material for microwave applications is demonstrated by the excellent performance characteristics of K-band GaAs power field-effect transistors (FETs) fabricated on the MBE wafers. An output power of 710 mW with 4.5-dB gain and 17.7 percent power-added efficiency was achieved at 21 GHz with a 1.26-mm gate width pi-gate device. A similar device with a 0.56-mm gate width produced an output power of 320 mW with 5.0-dB gain and 26.6 percent power-added efficiency at 21 GHz. These are the best results yet reported to date for GaAs power FETs operated in the K-band frequency range.

  1. Quick pH-responsive Films Prepared from Urethane Acrylate Anionomers Under UV Radiation and Their Responsive Performances

    Institute of Scientific and Technical Information of China (English)

    TANG Li-ming; DAI Yu; Fang Yu

    2004-01-01

    Urethane acrylate anionomers(UAA) were prepared in various compositions by three steps. Under UV radiation, UAA formed pH-sensitive films with drying film thicknesses of 60, 200 and 330μm. The equilibrium swelling ratios(SR) of the films in various pH buffer solutions increased with the increase of the molecule weight of UAA. The influence of the film thicknesses on the swelling performances of the films was investigated. The film with a thickness of 60 μm could reach the equilibrium state in 2.5-3.5 min. A high SR was obtained for a thick film due to its low average network density. The cured film could swell reversibly and rapidly with the change of pH, which is important for a controlled release system.

  2. Enhancing assertiveness in district nurse specialist practice.

    Science.gov (United States)

    Green, Julie

    2016-08-02

    District nurse (DN) care delivery has undergone substantial change in recent years due to changing demographics and service delivery demands that have called for a move of care delivery from secondary to primary care. The title District Nurse is recorded with the Nursing and Midwifery Council (NMC) on completion of the Specialist Practice Qualification in District Nursing (SPQ DN), which purports to be a 'transformational' course that prepares future caseload holders to manage their team and prioritise care delivery effectively. This article explores the need for assertiveness skills in this role in response to Australian research, and outlines the pedagogic interventions implemented during the SPQ DN course to enhance this skill. Assertiveness scores were monitored for the duration of the course and demonstrated a significant increase-a topic that is now the subject of a future, funded study.

  3. PC/ASA合金的研发%Research on PC/ASA Alloy Performance and Preparation Process

    Institute of Scientific and Technical Information of China (English)

    黄李胜; 李景; 麦伟宗; 赖世亮

    2016-01-01

    利用双螺杆挤出机制备PC/ASA合金,探讨了不同PC与ASA配比对性能的影响。结果表明:在PC/ASA体系中,PC与ASA的配比为70∶30,添加4%的相容剂SMA以及0.8%的抗氧剂、润滑剂,能获得最优的性能:悬臂梁缺口冲击强度达66.7kJ/m2,拉伸强度达56.1MPa,弯曲强度达82.3MPa,热变形温度达105.6℃;同时比同等条件下制备出来的PC/ABS合金拥有更好的耐光性。%Using a twin-screw extruder equipment,PC/ASA alloy was prepared,the effects of different ratio of PC and ASA on performance were investigated. The results showed that:in PC/ASA system,PC and ASA ratio is 70∶30,adding compatibility agent SMA 4% and 0. 8% of antioxidant and lubricant,can achieve optimal perform-ance:Izod notched impact strength of 66. 7kJ/m2 , the tensile strength of 56. 1MPa, the bending strength of 82. 3MPa,heat distortion temperature of 105. 6℃;while PC/ABS was prepared under the same conditions,PC/ASA alloy has better lightfastness than PC/ABS.

  4. Creation of nanopores on graphene planes with MgO template for preparing high-performance supercapacitor electrodes

    Science.gov (United States)

    Wang, Huanjing; Sun, Xiuxia; Liu, Zonghuai; Lei, Zhibin

    2014-05-01

    constant were achieved when compared with those of nonporous and stacked graphene electrodes. The method demonstrated herein would open up an opportunity to prepare porous graphene for a wide applications in energy storage, biosensors, nanoelectronics and catalysis. Electronic supplementary information (ESI) available: TGA curve, SEM and XRD patterns of MgO; TEM image of Mg5(CO3)4(OH)2.4H2O HRTEM; Raman spectrum of porous graphene, and its electrochemical performance including CV and galvanostatic charge-discharge curves in a three-electrode cell with 6.0 mol L-1 aqueous KOH as electrolyte; comparative electrocapacitive performances of graphene materials prepared by various methods; CV behaviors of porous graphene in two-electrode cell and the last 10 cycles in 1000 charge-discharge cycles in 1.0 mol L-1 TEABF4/AN electrolyte. See DOI: 10.1039/c4nr00538d

  5. ResourceCheck: Assess Your District's Resource Use

    Science.gov (United States)

    Education Resource Strategies, 2013

    2013-01-01

    For over a decade, Education Resource Strategies, Inc. (ERS) has helped leaders of urban school districts strategically reallocate their resources to improve student performance. This work identifies seven Core Transformational Strategies that support high-performing schools; in high-functioning districts, resources (people, time, and money) are…

  6. Malaria prevalence in Nias District, North Sumatra Province, Indonesia

    Directory of Open Access Journals (Sweden)

    Laowo Idaman

    2007-08-01

    Full Text Available Abstract Background The Nias district of the North Sumatra Province of Indonesia has long been known to be endemic for malaria. Following the economic crisis at the end of 1998 and the subsequent tsunami and earthquake, in December 2004 and March 2005, respectively, the malaria control programme in the area deteriorated. The present study aims to provide baseline data for the establishment of a suitable malaria control programme in the area and to analyse the frequency distribution of drug resistance alleles associated with resistance to chloroquine and sulphadoxine-pyrimethamine. Methods Malariometric and entomology surveys were performed in three subdistricts. Thin and thick blood smears were stained with Giemsa and examined under binocular light microscopy. Blood blots on filter paper were also prepared for isolation of parasite and host DNA to be used for molecular analysis of band 3 (SAO, pfcrt, pfmdr1, dhfr, and dhps. In addition, haemoglobin measurement was performed in the second and third surveys for the subjects less than 10 years old. Results Results of the three surveys revealed an average slide positivity rate of 8.13%, with a relatively higher rate in certain foci. Host genetic analysis, to identify the Band 3 deletion associated with Southeast Asian Ovalocytosis (SAO, revealed an overall frequency of 1.0% among the 1,484 samples examined. One hundred six Plasmodium falciparum isolates from three sub-districts were successfully analysed. Alleles of the dhfr and dhps genes associated with resistance to sulphadoxine-pyrimethamine, dhfr C59R and S108N, and dhps A437G and K540E, were present at frequencies of 52.2%, 82.5%, 1.18% and 1.18%, respectively. The pfmdr1 alleles N86Y and N1042D, putatively associated with mefloquine resistance, were present at 31.4% and 2%, respectively. All but one sample carried the pfcrt 76T allele associated with chloroquine resistance. Entomologic surveys identified three potential anopheline vectors in

  7. Groundwater Managment Districts

    Data.gov (United States)

    Kansas Data Access and Support Center — This dataset outlines the location of the five Groundwater Management Districts in Kansas. GMDs are locally formed and elected boards for regional groundwater...

  8. Municipal League Districts

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — This dataset contains boundaries for the Municipal League Districts in New Mexico. It is a vector digital data structure at a scale of 1:100,000.

  9. NM School District Boundaries

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — The dataset represents the boundaries of all public school districts in the state of New Mexico. The source for the data layer is the New Mexico Public Education...

  10. Allegheny County Council Districts

    Data.gov (United States)

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — This dataset portrays the boundaries of the County Council Districts in Allegheny County. The dataset is based on municipal boundaries and City of Pittsburgh ward...

  11. NM Property Tax Districts

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — This layer represents boundaries for New Mexico tax district "OUT" categories and incorporated/municipal "IN" categories as identified on the "Certificate of Tax...

  12. ACT250 Districts

    Data.gov (United States)

    Vermont Center for Geographic Information — The ACT 250 Districts layer is part of a larger dataset that contains administrative boundaries for Vermont's Agency of Natural Resources. The dataset includes...

  13. Solid Waste Management Districts

    Data.gov (United States)

    Vermont Center for Geographic Information — The Solid waste management districts layer is part of a dataset that contains administrative boundaries for Vermont's Agency of Natural Resources. This dataset...

  14. Allegheny County Council Districts

    Data.gov (United States)

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — This dataset portrays the boundaries of the County Council Districts in Allegheny County. The dataset is based on municipal boundaries and City of Pittsburgh ward...

  15. Enhanced photoelectrochemical performance of Ti-doped hematite thin films prepared by the sol-gel method

    Science.gov (United States)

    Lian, Xiaojuan; Yang, Xin; Liu, Shangjun; Xu, Ying; Jiang, Chunping; Chen, Jinwei; Wang, Ruilin

    2012-01-01

    Ti-doped α-Fe2O3 thin films were successfully prepared on FTO substrates by the sol-gel route. Hematite film was characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), and energy dispersive spectrometer (EDS). The XRD data showed α-Fe2O3 had a preferred (1 1 0) orientation which belonged to the rhombohedral system. Interestingly, the grains turned into worm-like shape after annealed at high temperature. The IPCE could reach 32.6% at 400 nm without any additional potential vs. SCE. Titanium in the lattice can affect the photo electro chemical performance positively by increasing the conductivity of the thin film. So the excited electrons and holes could live longer, rather than recombining with each other rapidly as undoped hematite. And the efficient carrier density on the Ti-doped anode surface was higher than the undoped anode, which contribute to the well PEC performance.

  16. The effect of physical and chemical treatment on nano-zeolite characterization and their performance in dimethyl ether preparation

    Directory of Open Access Journals (Sweden)

    Sanaa M. Solyman

    2015-09-01

    Full Text Available Catalytic dehydration of methanol to dimethyl ether (DME was investigated using physically and chemically modified H-Mordenite and H-Beta zeolites as catalysts. Physical modification was carried out using ultrasonic wave’s energy, while chemical modification was performed through impregnation in aluminum nitrate followed by calcination. The produced solid catalysts were evaluated as selective catalysts for the dehydration of methanol to dimethyl ether at 100–250 °C performed at three different contact times. Chemical and structural characterizations of the solid catalysts were identified using XRD, FT-IR, TEM, SEM and NH3-TPD. Ultrasonication physical mixing of solids proved as useful tool of preparation, producing fine reordered crystals of nanocomposite zeolites with novel morphology. The newly ordered crystals were distinguished by their frame work structure, acidic properties, crystal and particle sizes, unit cell volume, pore opening, and favorable catalytic activity of 100% selectivity to DME at 200 °C for all contact times studied. The effects of Al2O3 on the dispersion and interaction within the nano-zeolite crystals and hence on the catalytic dehydration of methanol were verified as the major influence toward utmost selectivity.

  17. A facile and scalable method to prepare carbon nanotube-grafted-graphene for high performance Li-S battery

    Science.gov (United States)

    Wang, Q. Q.; Huang, J. B.; Li, G. R.; Lin, Z.; Liu, B. H.; Li, Z. P.

    2017-01-01

    A carbon nanotube-grafted-graphene (CNT-g-Gr) is developed for enhancements of electrical conduction and polysulfide (PS) absorption to improve rate performance and cycleability of lithium-sulfur battery. The CNT-g-Gr is prepared through CNT growth on Ni-deposited graphene sheet which is fabricated via pyrolysis of glucose in a molten salt. The obtained CNT-g-Gr shows much higher specific surface area and PS adsorption capability than graphene. The in-situ formed Ni nanoparticles on graphene sheet not only serve as the catalytic sites for CNT growth, but also function as the anchor-sites for polar PS absorption. The CNT-g-Gr contributes a superb PS adsorption capability arising from graphene and CNT absorbing weakly-polar PS species, and Ni nanoparticles absorbing the species with stronger polarity. The resultant Li-S battery with the CNT-g-Gr shows excellent cycleability and rate performance. A stable discharge capacity of 900 mAh g-1 (with low capacity degradation rate) and a rate capacity of 260 mAh g-1 at 30 C discharge rate have been achieved.

  18. Facile preparation of carbon wrapped copper telluride nanowires as high performance anodes for sodium and lithium ion batteries

    Science.gov (United States)

    Yu, Hong; Yang, Jun; Geng, Hongbo; Chao Li, Cheng

    2017-04-01

    Uniform carbon wrapped copper telluride nanowires were successfully prepared by using an in situ conversion reaction. The length of these nanowires is up to several micrometers and the width is around 30–40 nm. The unique one dimensional structure and the presence of conformal carbon coating of copper telluride greatly accommodate the large volumetric changes during cycling, significantly increase the electrical conductivity and reduce charge transfer resistance. The copper telluride nanowires show promising performance in a lithium ion battery with a discharge capacity of 130.2 mA h g‑1 at a high current density of 6.0 A g‑1 (26.74 C) and a stable cycling performance of 673.3 mA h g‑1 during the 60th cycle at 100 mA g‑1. When evaluated as anode material for a sodium ion battery, the copper telluride nanowires deliver a reversible capacity of 68.1 mA h g‑1 at 1.0 A g‑1 (∼4.46 C) and have a high capacity retention of 177.5 mA h g‑1 during the 500th cycle at 100 mA g‑1.

  19. Facile preparation of three-dimensional multilayer porous MnO2/reduced graphene oxide composite and its supercapacitive performance

    Science.gov (United States)

    Li, Yiju; Wang, Guiling; Ye, Ke; Cheng, Kui; Pan, Yue; Yan, Peng; Yin, Jinling; Cao, Dianxue

    2014-12-01

    Three-dimensional (3D) multilayer porous MnO2/reduced graphene oxide composites are coated on a nickel foam substrate (denoted as MnO2/R-GO@Ni-foam) by a facile and scalable spray method following by low temperature annealing. The composite electrodes are characterized using X-ray diffraction, scanning electron microscopy, transmission electron microscopy and Fourier transform infrared spectroscopy. The content of MnO2 in the MnO2/R-GO@Ni-foam composites is determined by thermal gravimetric analysis. The supercapacitive performance of the composite electroides is investigated by cyclic voltammetry, galvanostatic charge-discharge and electrochemical impedance spectroscopy. The results show that the MnO2/R-GO@Ni-foam composite displays a high specific capacitance of 267 F g-1 at 0.25 A g-1 and excellent capacitance retention of 89.5% after 1000 cycles. This study provides a facile way for the preparation of composite electrodes for high-performance supercapacitor.

  20. Preparation and Performance of Poly(butyl fumarate-Based Material for Potential Application in LED Encapsulation

    Directory of Open Access Journals (Sweden)

    Liang Wang

    2017-02-01

    Full Text Available A UV-curable poly(butyl fumarate (PBF/poly(propylene fumarate-diacrylate (PPF-DA hybrid material with good performance for LED encapsulation is introduced in the paper. They have been prepared by radical polymerization using PBF and PPF-DA macromers with a UV curing system. PBF and PPF-DA were characterized by Fourier-transform infrared (FT-IR and H-nuclear magnetic resonance (1H NMR. The thermal behavior, optical and mechanical properties of the material were examined by thermogravimetric analysis (TGA, differential scanning calorimetry (DSC, ultraviolet-visible spectroscopy (UV–vis, and a material testing system mechanical testing machine, respectively. The results indicated that the hybrid material has a suitable refractive index (n = 1.537 and high transmittance (99.64% in visible range before/after thermal aging. With the increasing of the double bond ratio from 0.5 to 2, the water absorption ratios of the prepared encapsulation material were 1.22%, 1.87% and 2.88%, respectively. The mechanical property experiments showed that bonding strength was in the range of 1.86–3.40 MPa, tensile-shear strength ranged from 0.84 MPa to 1.57 MPa, and compression strength was in the range of 5.10–27.65 MPa. The cured PBF/PPF-DA hybrid material can be used as a light-emitting diode (LED encapsulant, owing to its suitable refractive index, high transparency, excellent thermal stability, lower water absorption, and good mechanical properties.

  1. Study of the performance of vanadium based catalysts prepared by grafting in the oxidative dehydrogenation of propane

    Energy Technology Data Exchange (ETDEWEB)

    Santacesaria, E.; Carotenuto, G.; Tesser, R.; Di Serio, M. [Naples Univ. (Italy). Dept. of Chemistry

    2011-07-01

    The oxidative dehydrogenation (ODH) of propane has been investigated by using many different vanadia based catalysts, prepared by grafting technique and containing variable amounts of active phase supported on SiO{sub 2} previously coated, by grafting in three different steps, with multilayer of TiO{sub 2}. A depth catalytic screening, conducted in a temperature range of 400-600 C, at atmospheric pressure and in a range of residence time W/F=0.08-0.33 ghmol{sub -1}, has shown that the vanadium oxide catalysts on TiO{sub 2}-SiO{sub 2} support, prepared by grafting have good performances in the ODH of propane. In particular, a preliminary study has demonstrated that higher selectivities can be obtained employing catalysts having a well dispersed active phase that can be achieved with a V{sub 2}O{sub 5} content lower than 10%{sub w}t. It is well known that, in the case of redox catalysts, an increase of the selectivity can be achieved not only by using an adequate catalytic system but also via engineering routes like decoupling catalytic steps of reduction and re-oxidation. In fact it has been observed that by operating in dehydrogenating mode, on the same catalysts, a higher selectivity is obtained although the catalyst is poisoned by the formation of coke on the surface. As consequence of the results obtained in dehydrogenation, in this work has been explored the possibility to feed low amounts of oxygen, below the stoichiometric level with the aim to keep clean the surface from coke but maintaining high the selectivity, because, dehydrogenation reaction prevails. In this work, the behavior of catalysts containing different amounts of V2O5 has been studied in the propane-propene reaction by using different ratios C{sub 3}H{sub 8}/O{sub 2} included in the range 0-2. (orig.)

  2. Photoprecursor Approach Enables Preparation of Well-Performing Bulk-Heterojunction Layers Comprising a Highly Aggregating Molecular Semiconductor.

    Science.gov (United States)

    Suzuki, Mitsuharu; Yamaguchi, Yuji; Takahashi, Kohei; Takahira, Katsuya; Koganezawa, Tomoyuki; Masuo, Sadahiro; Nakayama, Ken-ichi; Yamada, Hiroko

    2016-04-06

    Active-layer morphology critically affects the performance of organic photovoltaic cells, and thus its optimization is a key toward the achievement of high-efficiency devices. However, the optimization of active-layer morphology is sometimes challenging because of the intrinsic properties of materials such as strong self-aggregating nature or low miscibility. This study postulates that the "photoprecursor approach" can serve as an effective means to prepare well-performing bulk-heterojunction (BHJ) layers containing highly aggregating molecular semiconductors. In the photoprecursor approach, a photoreactive precursor compound is solution-deposited and then converted in situ to a semiconducting material. This study employs 2,6-di(2-thienyl)anthracene (DTA) and [6,6]-phenyl-C71-butyric acid methyl ester as p- and n-type materials, respectively, in which DTA is generated by the photoprecursor approach from the corresponding α-diketone-type derivative DTADK. When only chloroform is used as a cast solvent, the photovoltaic performance of the resulting BHJ films is severely limited because of unfavorable film morphology. The addition of a high-boiling-point cosolvent, o-dichlorobenzene (o-DCB), to the cast solution leads to significant improvement such that the resulting active layers afford up to approximately 5 times higher power conversion efficiencies. The film structure is investigated by two-dimensional grazing-incident wide-angle X-ray diffraction, atomic force microscopy, and fluorescence microspectroscopy to demonstrate that the use of o-DCB leads to improvement in film crystallinity and increase in charge-carrier generation efficiency. The change in film structure is assumed to originate from dynamic molecular motion enabled by the existence of solvent during the in situ photoreaction. The unique features of the photoprecursor approach will be beneficial in extending the material and processing scopes for the development of organic thin-film devices.

  3. Investigating the implications of meteorological indicators of seasonal rainfall performance on maize yield in a rain-fed agricultural system: case study of Mt. Darwin District in Zimbabwe

    Science.gov (United States)

    Mushore, Terence; Manatsa, Desmond; Pedzisai, Ezra; Muzenda-Mudavanhu, Chipo; Mushore, Washington; Kudzotsa, Innocent

    2017-08-01

    The study focuses on the impacts of climate variability and change on maize yield in Mt. Darwin District. The rainfall and temperature data for the period under study that is from 1992 to 2012 were obtained from Meteorological Services Department of Zimbabwe at daily resolution while crop yield data were obtained from Department of Agricultural, Technical and Extension Services (AGRITEX) and Zimbabwe Statistics Agency (ZIMSTAT) at seasonal/yearly resolution. In order to capture full rainfall seasons, a year was set to begin on 1 June and end on 31 July the next year. Yearly yield, temperature and rainfall data were used to compute time series analysis of rainfall, temperature and yield. The relationship between temperature, rainfall, quality of season (start, cessation, dry days, wet days and length) and yield was also investigated. The study also investigated the link between meteorological normal and maize yield. The study revealed that temperature is rising while rainfall is decreasing with time hence increasing risk of low maize yield in Mt. Darwin. Correlation between maize yield was higher using a non-linear ( R 2 = 0.630) than a linear regression model ( R 2 = 0.173). There was a very high correlation between maize yield and number of dry days ( R = -0.905) as well as between maize yield and length of season ( R = 0.777). We also observed a strong correlation between percentage normal rainfall and percentage normal maize yield ( R 2 = 0.753). This was also agreed between rainfall tessiles and maize yield tessiles as 50 % of the seasons had normal and above normal rainfall coinciding with normal and above normal maize yield. Of the 21 seasons considered, only one season had above normal rainfall while maize yield was below normal. The study concluded that there is a strong association between meteorological normal and maize yield in a rain-fed agricultural system. Climate information remains crucial to agricultural productivity hence the need to train farmers

  4. Investigating the implications of meteorological indicators of seasonal rainfall performance on maize yield in a rain-fed agricultural system: case study of Mt. Darwin District in Zimbabwe

    Science.gov (United States)

    Mushore, Terence; Manatsa, Desmond; Pedzisai, Ezra; Muzenda-Mudavanhu, Chipo; Mushore, Washington; Kudzotsa, Innocent

    2016-06-01

    The study focuses on the impacts of climate variability and change on maize yield in Mt. Darwin District. The rainfall and temperature data for the period under study that is from 1992 to 2012 were obtained from Meteorological Services Department of Zimbabwe at daily resolution while crop yield data were obtained from Department of Agricultural, Technical and Extension Services (AGRITEX) and Zimbabwe Statistics Agency (ZIMSTAT) at seasonal/yearly resolution. In order to capture full rainfall seasons, a year was set to begin on 1 June and end on 31 July the next year. Yearly yield, temperature and rainfall data were used to compute time series analysis of rainfall, temperature and yield. The relationship between temperature, rainfall, quality of season (start, cessation, dry days, wet days and length) and yield was also investigated. The study also investigated the link between meteorological normal and maize yield. The study revealed that temperature is rising while rainfall is decreasing with time hence increasing risk of low maize yield in Mt. Darwin. Correlation between maize yield was higher using a non-linear (R 2 = 0.630) than a linear regression model (R 2 = 0.173). There was a very high correlation between maize yield and number of dry days (R = -0.905) as well as between maize yield and length of season (R = 0.777). We also observed a strong correlation between percentage normal rainfall and percentage normal maize yield (R 2 = 0.753). This was also agreed between rainfall tessiles and maize yield tessiles as 50 % of the seasons had normal and above normal rainfall coinciding with normal and above normal maize yield. Of the 21 seasons considered, only one season had above normal rainfall while maize yield was below normal. The study concluded that there is a strong association between meteorological normal and maize yield in a rain-fed agricultural system. Climate information remains crucial to agricultural productivity hence the need to train farmers to

  5. Assessment of Policy Performance of School District Consolidation Pcy and Improving Strategies%新时期美国印第安纳州学区合并的绩效评估与改进策略

    Institute of Scientific and Technical Information of China (English)

    赵丹; 吴宏超

    2015-01-01

    近年来,美国地方政府面临财政紧缩的压力,导致公共服务的经费投入大幅缩减,学校教育服务也不例外。美国印第安纳州学区合并政策便是经济水平下降对教育发展产生影响的直接产物。在以“缩减教育成本”为初始目标的政策实施过程中,教育质量下滑引起了社会各界的关注。政府构建了“基于质量提升与成本缩减”的学区合并绩效评估体系,并逐渐将政策目标调整为“教育质量优先,兼顾成本缩减”,成功地实现了提高教育质量与缩减成本的双重目标,有效地促进了学区合并的顺利实施。其卓有成效的政策评估体系和兼容的政策取向对我国农村学校布局调整具有重要的借鉴意义。%In light of financial crisis in Indiana State as well as other states in the U.S, the input money on public services has shrunk much in recent years, education is not an exception. Accordingly, the policy of school district consolidation is implemented aiming at saving cost and enhancing educational efficiency, through merging adjacent districts. In the implementation of policy with the initial goal of reducing educational cost, the decline of educational quality has drew public attention. The government has established performance evaluation system of school districts consolidation which are based on quality improvement and cost reduction. Then, the government adjusted the policy goal to“educational quality first, taking cost-saving into account as well”, which makes it a dual goal of improving educational quality and saving cost, and which contributes to the successful implentation of school districts’consolidation. Therefore, there are great implications for the effective policy evaluation system and the compatible policy orientation on the adjustment of rural schools’layout of our country.

  6. In situ one-pot preparation of reduced graphene oxide/polyaniline composite for high-performance electrochemical capacitors

    Science.gov (United States)

    Chen, Nali; Ren, Yapeng; Kong, Peipei; Tan, Lin; Feng, Huixia; Luo, Yongchun

    2017-01-01

    Reduced graphene oxide/polyaniline (rGO/PANI) composites are prepared through an effective in situ one-pot synthesis route that includes the reduction of graphene oxide (GO) by aniline under weak alkali condition via hydrothermal method and then followed by in situ polymerization of aniline. X-ray diffraction, Fourier transform infrared spectroscopy, Raman spectroscopy, ultraviolet-visible spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscope and transmission electron microscope are employed to reveal that GO is successfully reduced by aniline under weak alkali condition and PANI can be deposited on the surfaces of reduced graphene oxide (rGO) sheets. The effect of rGO is optimized by tuning the mass ratios of aniline to GO to improve the electrochemical performance of rGO/PANI composites. The maximum specific capacitance of rGO/PANI composites achieves 524.4 F/g with a mass ratio of aniline to GO 10:1 at a current density of 0.5 A/g, in comparison to the specific capacitance of 397 F/g at the same current density of pure PANI. Particularly, the specific capacity retention rate is 81.1% after 2000 cycles at 100 mv/s scan rate, which is an improvement over that of pure PANI (55.5%).

  7. Electrochemical performance of nanocrystalline LiMPO{sub 4} thin-films prepared by electrostatic spray deposition

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Jun; Qin, Qi-Zong [Department of Chemistry, Laser Chemistry Institute, Fudan University, Shanghai 200433 (China)

    2005-09-15

    LiMPO{sub 4} (M=Mn, Fe) and LiMn{sub 0.4}Fe{sub 0.6}PO{sub 4} thin-films have been fabricated by electrostatic spray deposition (ESD) combined with sol-gel method, in which P{sub 2}O{sub 5} was used as a phosphorous resource in Li-M-P-O alcohol precursor solution. Analyses of LiMPO{sub 4} solid films using X-ray diffractometry (XRD) and scanning electron microscopy (SEM) demonstrated the formation of an olivine phase of space group Pmnb with nanocrystalline morphology. The prepared LiMPO{sub 4} films were evaluated electrochemically by cyclic-voltammetry and charge/discharge measurements. The results showed that thin-film electrode of LiMn{sub 0.4}Fe{sub 0.6}PO{sub 4} exhibited better electrochemical performance than that of pure LiFePO{sub 4} and LiMnPO{sub 4}. (author)

  8. Preparation and evaluation of surface-bonded tricationic ionic liquid silica as stationary phases for high-performance liquid chromatography.

    Science.gov (United States)

    Qiao, Lizhen; Shi, Xianzhe; Lu, Xin; Xu, Guowang

    2015-05-29

    Two tricationic ionic liquids were prepared and then bonded onto the surface of supporting silica materials through "thiol-ene" click chemistry as new stationary phases for high-performance liquid chromatography. The obtained columns of tricationic ionic liquids were evaluated respectively in the reversed-phase liquid chromatography (RPLC) mode and hydrophilic interaction liquid chromatography (HILIC) mode, and possess ideal column efficiency of 80,000 plates/m in the RPLC mode with naphthalene as the test solute. The tricationic ionic liquid stationary phases exhibit good hydrophobic and shape selectivity to hydrophobic compounds, and RPLC retention behavior with multiple interactions. In the HILIC mode, the retention and selectivity were evaluated through the efficient separation of nucleosides and bases as well as flavonoids, and the typical HILIC retention behavior was demonstrated by investigating retention changes of hydrophilic solutes with water volume fraction in mobile phase. The results show that the tricationic ionic liquid columns possess great prospect for applications in analysis of hydrophobic and hydrophilic samples.

  9. Effects of preparation methods on the performance of Cu-Mo-Fe-Ox in the hydrogen production from water

    Institute of Scientific and Technical Information of China (English)

    Si Chen; Wei Chu; Xu Liu; Dongge Tong

    2011-01-01

    Two Cu-Mo-Fe-Ox samples,which can store and supply pure hydrogen through repeated redox reaction (Fe3O4+4H2(→)3Fe+4H2O),were prepared by co-precipitation (FCM-C) and impregnation (FCM-I) methods,respectively,and the performance of hydrogen production from water were investigated.Compared with the impregnated sample,the co-precipitation sample presented better catalytic activity.The samples were characterized by X-ray diffraction (XRD),field emission scanning electron microscopy (FE-SEM),X-ray photoelectron spectroscopy (XPS),Fourier transform infrared spectroscopy (FT-IR) and temperature-programmed reduction (H2-TPR) techniques.XRD,FE-SEM and XPS results suggest that the FCM-C sample has smaller particle size and higher dispersion of iron oxide than that of FCM-I sample.In addition,FT-IR and H2-TPR analyses indicate that the weak interaction among metal oxides in FCM-C sample may induce facile reduction of active metal and superior property of hydrogen production by decomposing water in succession.

  10. Effects of Mo-doping on microstructure and near-infrared shielding performance of hydrothermally prepared tungsten bronzes

    Science.gov (United States)

    Wang, Qingjuan; Li, Can; Xu, Wenai; Zhao, Xiaolin; Zhu, Jingxin; Jiang, Haiwei; Kang, Litao; Zhao, Zhe

    2017-03-01

    Both Mo and W belong to VIB-sub-group, and possess similar ionic radii, electronegativity and oxide lattice configuration. Herein, Mo-doped (0-80 at.%) tungsten bronzes, MxWO3, were hydrothermally prepared to systematically explore the influence of Mo-doping on their micro-structure and optical performance. The products adopted a hexagonal structure within 6 at.% Mo-doping, and transformed into a monoclinic phase with higher Mo-doping content. Further tests suggested that 1.5 at.% Mo-doping is beneficial for the formation of pure hexagonal phase and uniform nano-rod morphology. Optical measures showed that all samples exhibited high and comparable visible transmittance (70-80%), but a very different near infrared (NIR) shielding ability. The sample doped with 1.5 at.% Mo demonstrated the best NIR shielding ability with a transmittance minimum of 20% at 1300 nm. Further increase of Mo-doping dosage remarkably deteriorated NIR shielding ability by depressing the absorption of localized surface plasmon resonance (LSPR). However, the optical absorption from small-polaron was less influenced by the introduction of Mo. As a result, Mo-doping caused an evident blue shift of the infrared absorption peaks from 1350 to 750 nm.

  11. Preparation and electrochemical performances of carbon sphere@ZnO core-shell nanocomposites for supercapacitor applications

    Science.gov (United States)

    Xiao, Xuechun; Han, Bingqian; Chen, Gang; Wang, Lihong; Wang, Yude

    2017-01-01

    Carbon sphere (CS)@ZnO core-shell nanocomposites were successfully prepared through facile low-temperature water-bath method without annealing treatment. The morphology and the microstructure of samples were characterized by transition electron microscopy (TEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS), respectively. ZnO nanoparticles with several nanometers in size decorated on the surface of the carbon sphere and formed a core-shell structure. Electrochemical performances of the CS@ZnO core-shell nanocomposites electrodes were investigated by cyclic voltammetry (CV) and galvanostatic charge/discharge (GDC). The CS@ZnO core-shell nanocomposite electrodes exhibit much larger specific capacitance and cycling stability is improved significantly compared with pure ZnO electrode. The CS@ZnO core-shell nanocomposite with mole ratio of 1:1 achieves a specific capacitance of 630 F g−1 at the current density of 2 A g−1. Present work might provide a new route for fabricating carbon sphere and transition metal oxides composite materials as electrodes for the application in supercapacitors. PMID:28057915

  12. Preparation of biological fish silage and its effect on the performance and meat quality characteristics of quails (Coturnix coturnix japonica

    Directory of Open Access Journals (Sweden)

    José Carmen Ramírez Ramírez

    2013-12-01

    Full Text Available The aim of the present study was to produce fish silage by lactic acid fermentation and evaluate its use in feeding of quails (Coturnix coturnix japonica. An oven-dried mixture of fish silage and soybean meal (1:1 w/w was used to prepare the diets with different levels of inclusion (0, 10, 20 and 30% and evaluate its effect on the performance and meat quality of 160 quails. The inclusion level did not affect the growth and feed conversion ratio. The carcass yield (70.3% and sensory quality of breast meat were not significantly different among the treatments (p>0.05. However, the concentration of unsaturated fatty acids such as oleic (C18:1n9C, linoleic (C18:2n6C, linolenic (C18:3n3, arachidonic (C20:4n6, cis eicosapentaenoic (C20:5n3 and cis docosahexaenoic (C22:6n3 increased in quail breast meat with the inclusion of fish silage:soybean mixture in the diet (p<0.05. Fish silage and its use in quail diets could offer a good alternative for fish waste utilization as feedstuff component for the improvement of fatty acid composition in its breast meat.

  13. Preparation of porous α-Fe2O3-supported Pt and its sensing performance to volatile organic compounds

    Institute of Scientific and Technical Information of China (English)

    Yuhong Cheng; Yanfei Kang; Liwei Wang; Yao Wang; Shurong Wang; Yujin Li; Wei Zhong; Liangqun Peng

    2012-01-01

    Porous α-Fe2O3 was synthesized by a simple hydrothermal treatment of FeCl3 aqueous solution followed by a calcination process.In the synthesis of porous α-Fe2O3,no templates or pore-directing agents were used.The as-prepared porous α-Fe2O3 was further employed as a support for loading Pt nanoparticles.The gas sensing performance of the obtained porous α-Fe2O3-supported Pt to VOCs was investigated.The sensor presented a high response and fast response-recovery characteristic to several VOCs including acetone,ether,methanol,ethanol,butanol and hexanol.Meanwhile,it exhibited a much higher response than the pure α-Fe2O3 at the operating temperature of 260℃.The enhanced sensing properties may be related to the unique porous structure of the α-Fe2O3 support and the promoting effect of active Pt nanoparticles for the sensing reactions.

  14. Preparation and characterization of 1-naphthylacetic acid-silica conjugated nanospheres for enhancement of controlled-release performance

    Science.gov (United States)

    Ao, Mingming; Zhu, Yuncong; He, Shun; Li, Deguang; Li, Pingliang; Li, Jianqiang; Cao, Yongsong

    2013-01-01

    Chemical pesticides have been widely used to increase the yield and quality of agricultural products as they are efficient, effective, and easy to apply. However, the rapid degradation and low utilization ratio of conventional pesticides has led to environmental pollution and resource waste. Nano-sized controlled-release formulations (CRFs) can provide better penetration through the plant cuticle and deliver the active ingredients efficiently to the targeted tissue. In this paper we reported novel conjugated nanospheres derived from 1-naphthylacetic acid (NNA), 3-aminopropyltriethoxysilane (APTES) and tetraethyl orthosilicate and their application as a controlled-release plant growth regulator. The NNA and APTES conjugate was prepared through a covalent cross-linking reaction and subsequent hydrolyzation and polycondensation to synthesize NNA-silica nanospheres. The release data indicated that the release of NNA was by non-Fickian transport and increased as particle size decreased. It was also found that the acidity-alkalinity was enhanced and as the temperature increased, the release of the active ingredient was faster. The nanoconjugate displayed a better efficacy in promoting root formation than NNA technical. The present study provides a novel synthesis route for CRFs comprising a pesticide, with long-duration sustained-release performance and good environmental compatibility. This method may be extended to other pesticides that possess a carboxyl group.

  15. Facile Preparation of Phosphotungstic Acid-Impregnated Yeast Hybrid Microspheres and Their Photocatalytic Performance for Decolorization of Azo Dye

    Directory of Open Access Journals (Sweden)

    Lan Chen

    2013-01-01

    Full Text Available Phosphotungstic acid (HPW-impregnated yeast hybrid microspheres were prepared by impregnation-adsorption technique through tuning pH of the aqueous yeast suspensions. The obtained products were characterized by field emission scanning electron microscopy (FE-SEM, energy dispersive spectrometry (EDS, X-ray diffraction (XRD, thermogravimetry-differential scanning calorimetry (TG-DSC, and ultraviolet-visible spectrophotometry (UV-Vis, respectively. FE-SEM and EDS ascertain that the HPW has been effectively introduced onto the surface of yeast, and the resulting samples retain ellipsoid shape, with the uniform size (length 4.5 ± 0.2 μm, width 3.0 ± 0.3 μm and good monodispersion. XRD pattern indicates that the main crystal structure of as-synthesized HPW@yeast microsphere is Keggin structure. TG-DTA states that the HPW in composites has better thermal stability than pure HPW. Fourier transform infrared spectroscopy (FT-IR elucidates that the functional groups or chemical bonds inherited from the pristine yeast cell were critical to the assembling of the composites. UV-Vis shows that the obtained samples have a good responding to UV light. The settling ability indicates that the hybrid microspheres possess an excellent suspension performance. In the test of catalytic activity, the HPW@yeast microsphere exhibits a high photocatalytic activity for the decoloration of Methylene blue and Congo red dye aqueous solutions, and there are a few activity losses after four cycles of uses.

  16. Performance of Electric Double Layer Capacitors using Active Carbons Prepared from Petroleum Coke by KOH and Vapor Re-Etching

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    The electrochemical storage of energy in a special kind of active carbon materials used as capacitor electrodes isconsidered. Pet roleum coke was used for preparation of carbons with different porosities by KOH and vapor etchingwith catalysis of FeCl3 in turn. Carbon electrodes were fabricated and used as electrodes of double layer capacitors.Nitrogen adsorption was used to characterize the porous structure of the carbons. The electrochemical performanceof the capacitors in 6 mol/L KOH was investigated with constant current charge and discharge experiments. Aspecific capacitance larger than 160 F/g was achieved with an electrode composed of 75% active carbon with aspecific surface area of 1180 m2/g and 20% graphite as conductive agent. Evaluation of capacitor performance wasconducted by different techniques, e.g. voltammetry and impedance spectroscopy. Characteristics of the capacitorwere also discussed. A hybrid power source consisting of nickel- hydrogen and double layer capacitor was demonstratedby powering successfully a simulated power load encountered in communication equipment.

  17. Preparation and performance of hydroxypropyl methylcellulose esters of substituted succinates for in vitro supersaturation of a crystalline hydrophobic drug.

    Science.gov (United States)

    Yin, Ligeng; Hillmyer, Marc A

    2014-01-06

    We prepared hydroxypropyl methylcellulose (HPMC) esters of substituted succinates and examined their performance for improving the aqueous solubility of crystalline hydrophobic drugs in spray-dried dispersions (SDDs). From one HPMC, we synthesized five HPMC esters using various monosubstituted succinic anhydrides. These HPMC esters along with a commercial HPMC acetate succinate (HPMCAS) were spray-dried from solutions with phenytoin. The SDDs with different matrices at 10 wt % loading had very similar bulk properties with a minimal amount of detectable crystalline phenytoin as revealed by scanning electron microscopy (SEM), powder X-ray diffraction (powder XRD), and differential scanning calorimetry (DSC). In solution, while the SDD with HPMCAS was very effective at achieving high levels of phenytoin supersaturation initially, it was not competent at maintaining such supersaturation due to the rapid crystallization of the dissolved phenytoin. Alternatively, SDDs with several synthesized HPMC esters of substituted succinates not only achieved rather high initial supersaturation but also maintained high concentrations for extended time (i.e., 1.5 h and longer). Such maintenance was largely ascribed to the inhibition of phenytoin nucleation. Structure-property relationships were established, and the most successful systems contained a high degree of substitution and a combination of a thioether with neighboring weak electron-withdrawing groups in the substituted succinic anhydrides. The effective maintenance of supersaturated solutions was only found in SDDs with rather low drug loadings, which indicates the significance of sufficiently high concentrations of polymer additives in the dissolution media.

  18. Effect of vibration frequency on microstructure and performance of high chromium cast iron prepared by lost foam casting

    Directory of Open Access Journals (Sweden)

    Wen-qi Zou

    2016-07-01

    Full Text Available In the present research, high chromium cast irons (HCCIs were prepared using the lost foam casting (LFC process. To improve the wear resistance of the high chromium cast irons (HCCIs, mechanical vibration was employed during the solidification of the HCCIs. The effects of vibration frequency on the microstructure and performance of the HCCIs under as-cast, as-quenched and as-tempered conditions were investigated. The results indicated that the microstructures of the LFC-produced HCCIs were refined due to the introduction of mechanical vibration, and the hardness was improved compared to that of the alloy without vibration. However, only a slight improvement in hardness was found in spite of the increase of vibration frequency. In contrast, the impact toughness of the as-tempered HCCIs increased with an increase in the vibration frequency. In addition, the wear resistance of the HCCIs was improved as a result of the introduction of vibration and increased with an increase in the vibration frequency.

  19. Preparation and electrochemical performances of carbon sphere@ZnO core-shell nanocomposites for supercapacitor applications

    Science.gov (United States)

    Xiao, Xuechun; Han, Bingqian; Chen, Gang; Wang, Lihong; Wang, Yude

    2017-01-01

    Carbon sphere (CS)@ZnO core-shell nanocomposites were successfully prepared through facile low-temperature water-bath method without annealing treatment. The morphology and the microstructure of samples were characterized by transition electron microscopy (TEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS), respectively. ZnO nanoparticles with several nanometers in size decorated on the surface of the carbon sphere and formed a core-shell structure. Electrochemical performances of the CS@ZnO core-shell nanocomposites electrodes were investigated by cyclic voltammetry (CV) and galvanostatic charge/discharge (GDC). The CS@ZnO core-shell nanocomposite electrodes exhibit much larger specific capacitance and cycling stability is improved significantly compared with pure ZnO electrode. The CS@ZnO core-shell nanocomposite with mole ratio of 1:1 achieves a specific capacitance of 630 F g‑1 at the current density of 2 A g‑1. Present work might provide a new route for fabricating carbon sphere and transition metal oxides composite materials as electrodes for the application in supercapacitors.

  20. Preparation of Nano-MnFe2O4 and Its Catalytic Performance of Thermal Decomposition of Ammonium Perchlorate

    Institute of Scientific and Technical Information of China (English)

    韩爱军; 廖娟娟; 叶明泉; 李燕; 彭新华

    2011-01-01

    Nano-MnFe2O4 particles were synthesized by co-precipitation phase inversion method and low-temperature combustion method respectively, using MnCl2, FeCl3, Mn(NO3)2, Fe(NO3)3, NaOH and C6H8O7. X-ray diffraction (XRD), transmission electron microscope (TEM), Fourier transform infrared spectroscopy (FT-IR), thermogravim-etry-differential thermal analysis (TG-DTA) and differential scanning calorimetry (DSC) were used to characterize the structure, morphology, thermal stability of MnFe2O4 and its catalytic performance to ammonium perchlorate. Results showed that single-phased and uniform spinel MnFe2O4 was obtained. The average particle size was about 30 and 20 nm. The infrared absorption peaks appeared at about 420 and 574 cm-1, and the particles were stable below 524 ℃. Using the two prepared catalysts, the higher thermal decomposition temperature of ammonium perchlorate was decreased by 77.3 and 84.9 ℃ respectively, while the apparent decomposition heat was increased by 482.5 and 574.3 J?g?1. The catalytic mechanism could be explained by the favorable electron transfer space provided by outer d orbit of transition metal ions and the high specific surface absorption effect of MnFe2O4 particles.

  1. Electric and mechanical performances of Bi0.5Sb1.5Te3 prepared by spark plasma sintering

    Institute of Scientific and Technical Information of China (English)

    XIAO Bo; CHEN Hui; WU Borong; ZHU Lei; LIU Mingyi; JIAN Xuyu; LI Lin

    2006-01-01

    Thermoelectric (TE) materials are a kind of functional materials which can be used to convert directly heat energy to electricity or reversely.The thermoelectric effects hold great potential for application in power generation and refrigeration.Bi2Te3 and its alloys are well known as best TE materials currently available near room temperature.This paper studies respectively the effects of spark plasma sintering (SPS) on electric performance of Bi0.5Sb1.5Te3 thermoelectric materials that are prepared through vacuum melting and ball milling.Through X-ray Diffraction and cold field emission scanning electric microscope s4800, the phase constituent and microstructure of the TE materials samples were analyzed.Electric conductivity and power factor can be improved with the rise of Spark Plasma Sintering temperature (from 300 to 500 ℃) and pressure(from 30 to 60 MPa), and the density and mechanical strength of Bi0.5Sb1.5Te3 thermoelectric material increase, too.

  2. Bacterial community shift and improved performance induced by in situ preparing dual graphene modified bioelectrode in microbial fuel cell.

    Science.gov (United States)

    Chen, Junfeng; Hu, Yongyou; Zhang, Lihua; Huang, Wantang; Sun, Jian

    2017-08-01

    Dual graphene modified bioelectrode (D-GM-BE) was prepared by in situ microbial-induced reduction of graphene oxide (GO) and polarity reversion in microbial fuel cell (MFC). Next Generation Sequencing technology was used to elucidate bacterial community shift in response to improved performance in D-GM-BE MFC. The results indicated an increase in the relative ratio of Proteobacteria, but a decrease of Firmicutes was observed in graphene modified bioanode (GM-BA); increase of Proteobacteria and Firmicutes were observed in graphene modified biocathode (GM-BC). Genus analysis demonstrated that GM-BE was beneficial to enrich electrogens. Typical exoelectrogens were accounted for 13.02% and 8.83% in GM-BA and GM-BC. Morphology showed that both GM-BA and GM-BC formed 3D-like graphene/biofilm architectures and revealed that the biofilm viability and thickness would decrease to some extent when GM-BE was formed. D-GM-BE MFC obtained the maximum power density by 124.58±6.32mWm(-2), which was 2.34 times over C-BE MFC. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Simultaneous determination of EDTA, sorbic acid, and diclofenac sodium in pharmaceutical preparations using high-performance liquid chromatography.

    Science.gov (United States)

    Heydari, Rouhollah; Shamsipur, Mojtaba; Naleini, Nasim

    2013-06-01

    A simple high-performance liquid chromatographic method for simultaneous determination of ethylenediaminetetraacetic acid (EDTA), sorbic acid, and diclofenac sodium was developed and validated. Separation was achieved on a C(18) column (10 cm×4.6 mm) using gradient elution. The mobile phase consisted of acetonitrile-ammonium dihydrogen phosphate buffer solution (0.01 M, pH=2.5, containing 0.8% tetra-n-butyl ammonium hydroxide). The detector wavelength was set at 254 nm. Under these conditions, separation of three compounds was achieved in less than 10 min. The effect of two metal salts and metal concentration on peak area of EDTA was investigated. The pH effect on retention of EDTA and sorbic acid was studied. The method showed linearity for EDTA, sorbic acid, and diclofenac in the ranges of 2.5-100.0, 5.0-200.0, and 20.0-120.0 μg/mL, respectively. The within- and between-day relative standard deviations ranged from 0.52 to 1.94%, 0.50 to 1.34%, and 0.78 to 1.67% for EDTA, sorbic acid, and diclofenac, respectively. The recovery of EDTA, sorbic acid, and diclofenac from pharmaceutical preparation ranged from 96.0-102.0%, 99.7-101.5%, to 97.0-102.5%, respectively. To the best of our knowledge, this is the first report about simultaneous determination of EDTA, sorbic acid, and diclofenac.

  4. Preparation and improved electrical performance of the Pr-doped CaMnO3-δ thermoelectric compound

    Science.gov (United States)

    Zhang, F. P.; Lu, Q. M.; Zhang, X.; Zhang, J. X.

    2013-09-01

    The rare earth Pr-doped Ca1-xPrxMnO3-δ (0 ⩽ x ⩽ 0.14) compound bulk samples are fabricated by citrate acid sol-gel combined with the ceramic preparation method. The effects of Pr doping on the structural and electrical transport properties of CaMnO3-δ within the high-temperature region are investigated in detail. The results show that single orthorhombic compounds can be formed in the experimental doping region. The remarkably reduced electrical resistivity is observed for the doped samples with the minimum value 3.90 mΩ cm at 373 K for the x = 0.14 sample; the absolute value of the Seebeck coefficient is decreased due to electron carrier concentration enhancement. The electrical properties of the doped samples are optimized compared with that of the parent sample, and the x = 0.08 sample is found to have the largest power factor value of 0.334 mW m-1 K-2 at 873 K. It is confirmed from the investigation that the electrical performance could be improved remarkably by rare earth Pr doping at a lower content.

  5. Facile preparation of porous Co3O4 nanosheets for high-performance lithium ion batteries and oxygen evolution reaction

    Science.gov (United States)

    Li, Zhangpeng; Yu, Xin-Yao; Paik, Ungyu

    2016-04-01

    Two dimensional (2D) porous nanostructures are of great interest due to their high surface area and rich edge sites, which are favorable for a wide variety of applications. In this communication, well-defined porous Co3O4 nanosheets (PCNSs) are successfully fabricated using graphene oxide as sacrificial template. The 2D structure and porous nature effectively provide more exposed active sites for electrochemical reaction and facilitate easier ion transportation across the sheets. As a result, the as-prepared PCNSs exhibit remarkable lithium storage performance, showing high reversible capacity of 1380 mAh g-1 even after 240 discharge/charge cycles at a current density of 500 mA g-1 and good rate capability (606 mAh g-1 at 10 A g-1). Moreover, it also shows a good electrocatalytic activity for the electrochemical oxygen evolution reaction with an overpotential of 368 mV for driving the current density of 10 mA cm-2 in 1 M KOH and a small Tafel slope of 59 mV dec-1.

  6. Highly nitrogen-doped carbon capsules: scalable preparation and high-performance applications in fuel cells and lithium ion batteries.

    Science.gov (United States)

    Hu, Chuangang; Xiao, Ying; Zhao, Yang; Chen, Nan; Zhang, Zhipan; Cao, Minhua; Qu, Liangti

    2013-04-07

    Highly nitrogen-doped carbon capsules (hN-CCs) have been successfully prepared by using inexpensive melamine and glyoxal as precursors via solvothermal reaction and carbonization. With a great promise for large scale production, the hN-CCs, having large surface area and high-level nitrogen content (N/C atomic ration of ca. 13%), possess superior crossover resistance, selective activity and catalytic stability towards oxygen reduction reaction for fuel cells in alkaline medium. As a new anode material in lithium-ion battery, hN-CCs also exhibit excellent cycle performance and high rate capacity with a reversible capacity of as high as 1046 mA h g(-1) at a current density of 50 mA g(-1) after 50 cycles. These features make the hN-CCs developed in this study promising as suitable substitutes for the expensive noble metal catalysts in the next generation alkaline fuel cells, and as advanced electrode materials in lithium-ion batteries.

  7. PREPARATION AND PERFORMANCE STUDIES ON POLYETHERSULFONE ULTRAFILTRATION MEMBRANES MODIFIED WITH GELATIN FOR TREATMENT OF TANNERY AND DISTILLERY WASTEWATER

    Directory of Open Access Journals (Sweden)

    S. Velu

    2015-03-01

    Full Text Available Abstract In this study polyethersulfone ultrafiltration membrane were prepared with the modifier gelatin at 0, 5, 10, 15 and 20 wt % using DMF as solvent by phase inversion process. Morphologies and characteristics of the membranes were investigated through the methods of SEM, XRD, contact angle measurements. The performance of the modified membrane for the treatment of leather and distillery wastewater through a deadend ultrafiltration process was studied. Morphological investigation showed that the 10% gelatin content in 90% PES results in a two layer structure with a porous top and homogeneous sub-layer with uniform number of pores on the surface. The pure water flux of the modified membrane increases with gelatin concentration, which results in better permeation for both leather and distillery wastewater. In addition to 80-90% reduction in BOD and COD, all modified PES UF membranes showed moderate removal of total suspended and dissolved solids, chlorides, sulphate, oil and grease, potassium, sodium and ammonical nitrogen, apart from color removal.

  8. Effect of vibration frequency on microstructure and performance of high chromium cast iron prepared by lost foam casting

    Institute of Scientific and Technical Information of China (English)

    Wen-qi Zou; Zhi-guo Zhang; Hao Yang; Wei Li

    2016-01-01

    In the present research, high chromium cast irons (HCCIs) were prepared using the lost foam casting (LFC) process. To improve the wear resistance of the high chromium cast irons (HCCIs), mechanical vibration was employed during the solidiifcation of the HCCIs. The effects of vibration frequency on the microstructure and performance of the HCCIs under as-cast, as-quenched and as-tempered conditions were investigated. The results indicated that the microstructures of the LFC-produced HCCIs were reifned due to the introduction of mechanical vibration, and the hardness was improved compared to that of the aloy without vibration. However, only a slight improvement in hardness was found in spite of the increase of vibration frequency. In contrast, the impact toughness of the as-tempered HCCIs increased with an increase in the vibration frequency. In addition, the wear resistance of the HCCIs was improved as a result of the introduction of vibration and increased with an increase in the vibration frequency.

  9. Design on the performance evaluation framework of district and county health system in Shanghai%上海区县卫生系统绩效评价概念框架设计

    Institute of Scientific and Technical Information of China (English)

    任建琳; 江力波; 彭颖; 王剑萍; 张勘

    2014-01-01

    本研究参照国际多个国家和组织的卫生服务系统绩效评估框架,结合上海区县卫生系统的特点,提出上海区县卫生系统绩效评价概念框架.其绩效框架包含2个一级评估目标和7个二级评估维度:在长期目标中,“健康状况”、“满意度”和“疾病风险保护”是区县卫生系统绩效的长期效果评估维度;在中期目标中,“可及性”、“成本”、“效率”和“质量”,是区县卫生系统绩效的中期效果评估维度.本研究旨在评价区县卫生系统改善健康能力的整体绩效.其三级指标有待进一步研究确立.%Shanghai district and county health system performance evaluation conceptual frameworkwas proposed based on health services system performance assessment frameworks raised by some countries and international organizations,and combined with Shanghai district and county health system characteristics.This framework contains two first grade indices and seven second grade indices:In the long term goals,'health','satisfaction' and 'disease risk protection' are the county's longterm effects of health system performance assessment dimensions; in the medium-term goals,the'accessibility','cost',' efficiency' and 'quality' are the county' s medium-term effects of health system performance assessment dimensions.This study aimed to evaluate Shanghai county health system's overall performance.Further study is needed in constructing its third grade indices.

  10. Facile preparation of magnetic mesoporous Fe3O4/C/Cu composites as high performance Fenton-like catalysts

    Science.gov (United States)

    Li, Keyan; Zhao, Yongqin; Janik, Michael J.; Song, Chunshan; Guo, Xinwen

    2017-02-01

    Fe-Cu composites with different compositions and morphologies were synthesized by a hydrothermal method combined with precursor thermal transformation. γ-Fe2O3/CuO and α-Fe2O3/CuO were obtained by calcining the Fe and Cu tartrates under air atmosphere at 350 °C and 500 °C, respectively, while Fe3O4/C/Cu was obtained by calcining the tartrate precursor under N2 atmosphere at 500 °C. The Fe3O4/C/Cu composite possessed mesoporous structure and large surface area up to 133 m2 g-1. The Fenton catalytic performance of Fe3O4/C/Cu composite was closely related to the Fe/Cu molar ratio, and only proper amounts of Fe and Cu exhibited a synergistic enhancement in Fenton catalytic activity. Cu inclusion reduced Fe3+ to Fe2+, which accelerated the Fe3+/Fe2+ cycles and favored H2O2 decomposition to produce more hydroxyl radicals for methylene blue (MB) oxidation. Due to the photo-reduction of Fe3+ and Cu2+, the Fenton catalytic performance was greatly improved when amending with visible light irradiation in the Fe3O4/C/Cu-H2O2 system, and MB (100 mg L-1) was nearly removed within 60 min. The Fe3O4/C/Cu composite showed good recyclability and could be conveniently separated by an applied magnetic field. Compared with conventional methods for mesoporous composite construction, the thermolysis method using mixed metal tartrates as precursors has the advantages of easy preparation and low cost. This strategy provides a facile, cheap and green method for the synthesis of mesoporous composites as excellent Fenton-like catalysts, without any additional reductants or organic surfactants.

  11. Interfacial thermodynamics and kinetics of sorption of diclofenac on prepared high performance flower-like MoS2.

    Science.gov (United States)

    Zhang, Yalei; Yin, Zengfu; Dai, Chaomeng; Zhou, Xuefei; Chen, Wen

    2016-11-01

    Flower-like MoS2 with numerous wrinkled nanosheets was prepared via a facile hydrothermal method. The surface morphology and microstructure of the obtained materials were characterized using X-ray diffraction data (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). Additionally, the compositions of the flower-like MoS2 were further revealed by an energy dispersion spectrometer (EDX) and X-ray photoelectron spectrometry (XPS). The obtained MoS2 was used as an adsorbent to remove diclofenac (DCF, C14H10Cl2NO2Na) from aqueous solutions and presented excellent performance for removing DCF. The sorption kinetics, isotherms and effect of solution pH on the sorption were evaluated in batch sorption experiments. The sorption characteristics of the interactions between DCF and MoS2 in water were analyzed using a pseudo-second-order model, an intraparticle diffusion model and Boyd model to determine the sorption rate-determining steps. It was concluded that the sorption of DCF on MoS2 was fitted better by the pseudo-second-order model and that external diffusion governed the sorption process of DCF onto the MoS2. The interfacial interaction free energies between DCF and MoS2 in the sorption process can be calculated based on the extended Derjaguin-Landau-Verwey-Overbeek (XDLVO). The flower-like MoS2 presenting excellent performance for removing DCF, could be a better choice of treating DCF-containing wastewaters.

  12. Evaluation of methods for preparing hydrogen-producing seed inocula under thermophilic condition by process performance and microbial community analysis.

    Science.gov (United States)

    O-Thong, Sompong; Prasertsan, Poonsuk; Birkeland, Nils-Kåre

    2009-01-01

    Five methods for preparation of hydrogen-producing seeds (base, acid, 2-bromoethanesulfonic acid (BESA), load-shock and heat shock treatments) as well as an untreated anaerobic digested sludge were compared for their hydrogen production performance and responsible microbial community structures under thermophilic condition (60 degrees C). The results showed that the load-shock treatment method was the best for enriching thermophilic hydrogen-producing seeds from mixed anaerobic cultures as it completely repressed methanogenic activity and gave the a maximum hydrogen production yield of 1.96 mol H(2) mol(-1) hexose with an hydrogen production rate of 11.2 mmol H(2) l(-1)h(-1). Load-shock and heat-shock treatments resulted in a dominance of Thermoanaerobacterium thermosaccharolyticum with acetic acid and butyric acid type of fermentation while base- and acid-treated seeds were dominated by Clostridium sp. and BESA-treated seeds were dominated by Bacillus sp. The comparative experimental results from hydrogen production performance and microbial community analysis showed that the load-shock treatment method was better than the other four methods for enriching thermophilic hydrogen-producing seeds from anaerobic digested sludge. Load-shock treated sludge was implemented in palm oil mill effluent (POME) fermentation and was found to give maximum hydrogen production rates of 13.34 mmol H(2) l(-1)h(-1) and resulted in a dominance of Thermoanaerobacterium spp. Load-shock treatment is an easy and practical method for enriching thermophilic hydrogen-producing bacteria from anaerobic digested sludge.

  13. Preparation and tribological performance of electrodeposited Ni-TiB2-Dy2O3 composite coatings

    Institute of Scientific and Technical Information of China (English)

    LIU Xiaozhen; LI Xin; YU Aibing; HUANG Weijue

    2009-01-01

    TiB2 and Dy2O3 were used as codeposited particles in the preparation of Ni-TiB2-Dy2O3 composite coatings to improve its per-formance. Ni-TiB2-Dy2O3 composite coatings were prepared by electrodeposition method with a nickel cetyltrimethylanunonium bromide and hexadecylpyridinium bromide solution containing TiB2 and Dy2O3 particles. The content of codeposited TiB2 and Dy2O3 in the compos-ite coatings was controlled by adding TiB2 and Dy2O3 particles of different concentrations into the solution, respectively. The effects of TiB2 and Dy2O3 content on microhardness, wear mass loss and friction coefficients of composite coatings were investigated. The composite coat-ings were characterized by X-ray diffraction (XRD), inductively coupled plasma-atomic emission spectrometer (ICP-AES) and scanning electron microscopy (SEM) techniques. Ni-TiB2-Dy2O3 composite coatings showed higher microhardness, lower wear mass loss and friction coefficient compared with those of the pure Ni coating and Ni-TiB2 composite coatings. The wear mass loss of Ni-TiB2-Dy2O3 composite coatings was 9 and 1.57 times lower than that of the pure Ni coating and Ni-TiB2 composite coatings, respectively. The friction coefficient of pure Ni coating, Ni-TiB2 and Ni-TiB2-Dy2O3 composite coatings were 0.723, 0.815 and 0.619, respectively. Ni-TiB2-Dy2O3 composite coat-ings displayed the least friction coefficient among the three coatings. DY2O3 particles in composite coatings might serve as a solid lubricant between contact surfaces to decrease the friction coefficient and abate the wear of the composite coatings. The loading-bearing capacity and the wear-reducing effect of the Dy2O3 particles were closely related to the content of Dy2O3 particles in the composite coatings.

  14. Isolation and Purification of Unstable Iridoid Glucosides from Traditional Chinese Medicine by Preparative High Performance Liquid Chromatography Coupled with Solid-phase Extraction

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    An efficient preparative method was successfully developed for isolation and purification of unstable components from medicinal plant extracts, using a combined method of preparative high performance liquid chro-matography(HPLC) and solid-phase extraction(SPE). The aim of this study was to obtain an effective method with high preparative efficiency and importantly to avoid the transformation of unstable compounds. The preparative HPLC system was based on an LC/MS controlled four-channel autopurification system. The SPE method was performed with a C18 packing material to trap the target compounds and to remove the acidic additive derived from the mobile phase. Using this method, the unstable iridoid glucosides(IGs) as model compounds were successfully isolated and purified from the extract of Hedyotis diffusa Willd. Six IGs(including one new minor IG) and one nucleotide compound were simultaneously obtained, each with a purity of 〉91% as determined by HPLC. The structures of the isolated compounds were identified by UPLC/Q-TOF MS, UV, 1D and/or 2D NMR. It was demonstrated that the combination of preparative HPLC with SPE is a versatile tool for preparative purification of unstable compounds from complex natural products.

  15. Diagnostic performance of CT colonography with limited cathartic preparation in colorectal cancer screening; comparison with conventional colonoscopy

    Directory of Open Access Journals (Sweden)

    Mohammed Farghally Amin

    2015-09-01

    Conclusion: This study proved that CTC with limited cathartic bowel preparation and iodinated agents for fecal tagging can obtain high sensitivity and PPV values results for <5 mm polyps comparable to those obtained with conventional preparation with laxatives. Furthermore, this method could really improve the acceptance of CTC for colorectal cancer screening.

  16. Ontario District Embraces an Evolving Approach to Learning

    Science.gov (United States)

    Belchetz, Denese; Witherow, Kathy

    2014-01-01

    The York Region District School Board is recognized as a high-performing district in Ontario, Canada, and has also garnered international attention. Visitors from across Canada, as well as Singapore, Finland, England, Scotland, Holland, the Bahamas, Korea, China, and Taiwan, have come to learn about its system and observe the teaching, learning,…

  17. Purification of six lignans from the stems of Schisandra chinensis by using high-speed counter-current chromatography combined with preparative high-performance liquid chromatography.

    Science.gov (United States)

    Zhu, Lijie; Li, Bin; Liu, Xiuying; Huang, Guohui; Meng, Xianjun

    2015-11-01

    A method for the preparative purification of lignans from Schisandra chinensis was established using a combination of high-speed counter-current chromatography (HSCCC) and preparative high-performance liquid chromatography (HPLC). The crude extracts obtained from S. chinensis by using 70% ethanol were separated on a macroporous resin column and then eluted with a graded ethanol series. A two-phase solvent system consisting of n-hexane-ethyl acetate-methanol-water (1:1:1:1, v/v) was used for HSCCC, and a mobile phase of acetonitrile-water (50:50, v/v) was used for preparative HPLC. The results obtained using HSCCC were compared with those obtained using preparative HPLC, and their advantages were further integrated to improve the separation efficiency. Six known lignans were identified by electrospray ionisation mass spectrometry and (1)H nuclear magnetic resonance (NMR) and (13)C NMR analyses; the purities of all the compounds were more than 91%.

  18. Government Districts, Other - MDC_CommissionerDistrictOffice

    Data.gov (United States)

    NSGIC Local Govt | GIS Inventory — A point feature class of Commissioner District Offices. Only District offices were included in this feature class. Main offices at the Stephen P. Clark Center were...

  19. Election Districts and Precincts, Voter districts, Published in 2006, Freelance.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Election Districts and Precincts dataset, was produced all or in part from Hardcopy Maps information as of 2006. It is described as 'Voter districts'. Data by...

  20. Special Taxing Districts, TIF districts, Published in 2006, Freelance.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Special Taxing Districts dataset, was produced all or in part from Published Reports/Deeds information as of 2006. It is described as 'TIF districts'. Data by...

  1. School Districts, School districts-Elementary, Published in 2002, Freelance.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This School Districts dataset, was produced all or in part from Hardcopy Maps information as of 2002. It is described as 'School districts-Elementary'. Data by this...

  2. School Districts, School districts-Middle, Published in 2002, Freelance.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This School Districts dataset, was produced all or in part from Hardcopy Maps information as of 2002. It is described as 'School districts-Middle'. Data by this...

  3. Studies of adaptive traits of Bali cattle in Buleleng district, Bali and Barru district, South Sulawesi

    Science.gov (United States)

    Aritonang, S. B.; Yuniati, R.; Abinawanto, Imron, M.; Bowolaksono, A.

    2017-05-01

    Bali cattle have high adaptability, so the distribution area is spread across Indonesia. These studies aimed to determine the effect of environmental factors on physiology performance of Bali cattle in Buleleng district and Barru district. Skin and rectal temperature and respiration rate within a minute were measured in cattle across 5-days. Ambient temperature, relative humidity, wind speed, and light intensity were measured as environmental factors. Our findings suggest that environmental factors between the two districts were different (pBPM, whereas in Barru it was 22-28 BPM. Our results indicate that the changes in environmental conditions affect changes in the cattle physiology profile in each district. Thus, Bali cattle have adaptability towards a variety of environmental conditions.

  4. Insights into Education's Race to the Top: Correlational Survey Exploring Perceptions of Organizational Culture and Change Ambivalence during the Implementation of a Mandated Performance Evaluation System in a Northeast U.S. School District

    Science.gov (United States)

    Schwamb, Andrea B.

    2013-01-01

    American public schools are currently facing a new mandated evaluation system that will create substantial change by requiring districts to evaluate professional staff based on two quantified measures: (a) state testing, and (b) a district determined measure. Although reforms have been at the forefront of policymakers' agendas, these initiatives…

  5. New Public Management and District Reform: Managerialism and Deflection of Local Leadership in a Texas School District

    Science.gov (United States)

    Maxcy, Brendan

    2009-01-01

    Examining work and community relations in one Texas school district, this study explores intensifying managerialism under performance accountability (PA) pressures. Reports, press releases, and media accounts are combined with ethnographic study from one elementary school to explore the enactment of school district reforms. Locating PA within a…

  6. [High performance preparation and structural confirmation of lignans from Schisandrae chinensis fructus by using HSCCC combined with ESI-MSn method].

    Science.gov (United States)

    Yu, Xiao-Li; Pi, Zi-feng; Hu, Xiu-Li; Song, Feng-Rui; Liu, Zhi-Qiang

    2014-01-01

    High-speed counter-current chromatography (HSCCC) was used to high performance separate and prepare lignans from Schisandrae chinensis fructus. The solvent system is composed of n-hexane-ethyl acetate-methanol-water (9 : 1 : 5 : 5) and n-hexane-ethyl acetate-methanol-water (9 : 1 : 9 : 5), speed is at 900 r.min-1, and flow rate is at 2.0 mL.min-1. Five fractions from Schisandrae chinensis fructus extract were separated and prepared with one HSCCC process. They were identified as schisandrin, gomisin J, schisandrol B, schisantherin A and deoxyschizandrin by electrospray ionization-multiple tandem mass spectrometry (ESI-MSn), respectively. Their contents were obtained in 98.74%, 94.32%, 99.53%, 94.23% and 98.68% by ultra high performance liquid chromatography (UPLC), separately. The rapid and simple method can be applied for the preparation of lignans from Schisandrae chinensis fructus.

  7. Determination of piroxicam in pharmaceutical preparations by ultraviolet direct spectrophotometry, ultraviolet difference spectrophotometry and high performance liquid chromatography

    Energy Technology Data Exchange (ETDEWEB)

    Hackmann, E.R.M.; Santos Gianotto, E.A. dos; Miritello Santoro, M.I.R. (Universidade de Sao Paulo (Brazil))

    1993-02-01

    Piroxicam in pharmaceutical preparations (capsules (C), tablets (T), oral drops (OD), suppositories (S) and simulated sample (SS)) was determined by UV direct spectrophotometry (UVS) at 333 nm, by UV difference spectrophotometry (UVDS) at 327 nm, and in C and T, by high performance liquid chromatography (HPLC). For UVS, Beer's law was obeyed in the range 3.0-8.5 [mu]g/mL. The coefficient of correlation (CC), absolute precision (AP) and relative precision (RP) were 0.9999, 0.02 and 0.33%, respectively. The coefficient of variation (CV) for C, T, OD, S and SS were 0.48%, 0.35%, 0.48% and 0.19%, respectively. The recovery average (RA) was 100.22%. For UVDS, Beer's law was obeyed in the range 5.0-15.0 [mu]g/mL. The CC, AP and RP were respectively 0.9999, 0.05 and 0.47%. The CV for C, T, OD, S and SS were 0.64%, 0.84%, 0.62%, 0.54% and 0.15%, respectively. The RA was 99.02%. In HPLC determination, a LiChrospher[reg sign] 100 RP-18 (5 [mu]m) in LiChroCART[reg sign] 125-4 column at ambient temperature with a mobile phase consisting of methanol: (buffer solution citric acid-dibasic sodium phosphate pH 3.0) (55:45) and UV detection at 254 nm enabled the determination of piroxicam in C and T. The response peak area versus concentration presented linearity in the range 10.0-100.0 [mu]g/mL. The CC, AP and RP were 0.9997, 0.45 and 0.90%, respectively. The CV was 0.51%-0.82% and the RA, 97.13%. 14 refs., 1 fig., 5 tabs.

  8. Effect of cathodic current density on performance of tungsten coatings on molybdenum prepared by electrodeposition in molten salt

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Fan, E-mail: jiangfan1109@163.com [Department of Materials and Physics, School of Physics and Optoelectronic Engineering, Nanjing University of Information Science and Technology, 219 Ningliu Road, Nanjing 210044, Jiangsu Province (China); School of Materials Science and Engineering, University of Science and Technology Beijing, 30 Xueyuan Road, Haidian District, Beijing 10083 (China)

    2016-02-15

    Graphical abstract: - Highlights: • Tungsten coatings were successfully electroplated on molybdenum substrate. • The electrodeposition was studied in the air atmosphere at 1173 K. • The coating had columnar structure with preferential growth orientation of (2 0 0). • The coating obtained at 50 mA cm{sup −2} had a maximum microhardness of 495 HV. - Abstract: Smooth tungsten coatings were prepared at current density below 70 mA cm{sup −2} by electrodeposition on molybdenum substrate from Na{sub 2}WO{sub 4}-WO{sub 3} -melt at 1173 K in air atmosphere. As the current density reached up to 90 mA cm{sup −2}, many significant nodules were observed on the surface of the coating. Surface characterization, microstructure and mechanical properties were performed on the tungsten coatings. As the increasing of current density, the preferred orientation of the coatings changed to (2 0 0). All coatings exhibited columnar-grained-crystalline. There was about a 2 μm thick diffusion layer between tungsten coating and molybdenum substrate. The bending test revealed the tungsten coating had –good bonding strength with the molybdenum substrate. There is a down trend of the grain size of the coating on molybdenum as the current density increased from 30 mA cm{sup −2} to 50 mA cm{sup −2}. The coating obtained at 50 mA cm{sup −2} had a minimum grain size of 4.57 μm, while the microhardness of this coating reached to a maximum value of 495 HV.

  9. Performance of rapid diagnostic test, blood-film microscopy and PCR for the diagnosis of malaria infection among febrile children from Korogwe District, Tanzania

    DEFF Research Database (Denmark)

    Mahende, Coline; Ngasala, Billy; Lusingu, John

    2016-01-01

    Background: Rapid diagnostic tests (RDT) and light microscopy are still recommended for diagnosis to guide the clinical management of malaria despite difficult challenges in rural settings. The performance of these tests may be affected by several factors, including malaria prevalence and intensi...

  10. Role-Play Technique as an Antecedent of Performance in English Language: Evidence from Secondary Schools in Wareng District, Uasin Gishu County, Kenya

    Science.gov (United States)

    Julius, Kemboi; Osman, Ahmed

    2015-01-01

    In Kenya, there is a national concern over English language dismal performance over the years in Kenya Certificate of Secondary Education (K.C.S.E). Blame has been put on teachers of English language for relying on techniques that favor them at the expense of their students. This article therefore sought to assess the use of role-play technique as…

  11. An Investigation on the Relationship between the School Level of Funding and Performance at K.C.S.E. in Mumias District, Western Province, Kenya

    Science.gov (United States)

    Sisungo, Z.; Kaberia, L.; Buhere, P.

    2014-01-01

    The Kenyan government has been spending between 20% to 40% of its revenue on education with the aim to improving access and quality. Much of these resources have been devoted towards establishment and procurement of school inputs such as classrooms, teachers and textbooks. This study investigated the effects of funding on performance in Mumias…

  12. The Impact of a Computer Based Math Instruction Program on Fifth Grade Student Academic Performance on the Texas Assessment of Knowledge and Skills in One School District

    Science.gov (United States)

    Abel, Brian B.

    2011-01-01

    This study was designed to investigate the differences between two groups of fifth grade students' performance on the 2010 fifth grade Texas Assessment of Knowledge and Skills (TAKS) math test. The sample consisted of a group of fifth grade students receiving the traditional instruction from their classroom teacher and a group of fifth grade…

  13. Unified School Districts, Census 2000

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — The New Mexico 2000 Unified School Districts layer was derived from the TIGER Line files from the US Census Bureau. The districts are clipped to the state...

  14. State Highway District Boundaries - 2004

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — This data represents the NM Department of Transportation District boundaries as legislatively defined (i.e. these are not maintenance defined districts).

  15. Resilient Schools: Connections between Districts and Schools

    Science.gov (United States)

    Whitney, Stephen; Maras, Melissa A.; Schisler, Lacey Jo

    2012-01-01

    High-performing, at-risk schools are not all equal in the challenges they face and the resources available. This study extends the research on at-risk schools by expanding the definition of at-risk to include risk factors beyond poverty. In addition, the study explicitly examines possible differences between district and school-level factors.…

  16. School Engagement as a Mediator of Academic Performance among Urban Youth: The Role of Career Preparation, Parental Career Support, and Teacher Support

    Science.gov (United States)

    Perry, Justin C.; Liu, Xiongyi; Pabian, Yvona

    2010-01-01

    Drawing from the contributions of vocational psychology, this study examined school engagement as a mediator of academic performance through the effects of career preparation (career planning, career decision-making self-efficacy), parental career support, and teacher support among diverse urban youth in middle school and high school (N = 285).…

  17. High-rate performance of Ti3+ self-doped TiO2 prepared by imidazole reduction for Li-ion batteries

    Science.gov (United States)

    Seok, Dong-il; Wu, Mihye; Shim, Kwang Bo; Kang, Yongku; Jung, Ha-Kyun

    2016-10-01

    Ti3+ self-doped TiO2 nanoparticles were prepared via a simple imidazole reduction process and developed as an anode material for Li-ion batteries. Introducing the Ti3+-state on TiO2 nanoparticles resulted in superior rate performances that the capacity retention of 88% at 50 C. The enhanced electrochemical performances were attributed to the resulting lower internal resistance and improved electronic conductivity, based on galvanostatic intermittent titration technique and electrochemical impedance spectroscopy analyses.

  18. District-Level Downsizing

    Science.gov (United States)

    Schachter, Ron

    2011-01-01

    Draconian cuts have become the order of business for many school districts since the economic recession hit in 2008. But for the coming school year, "draconian" has taken on an even harsher meaning, as states from California and Texas to Illinois and New York wrestle with deficits in the tens of billions of dollars and make…

  19. Isolation and Purification of Unstable Iridoid Glucosides from Traditional Chinese Medicine by Preparative High Performance Liquid Chromatography Coupled with Solid-phase Extraction

    Institute of Scientific and Technical Information of China (English)

    LI Cun-man; XIAO Yuan-sheng; XUE Xing-ya; FENG Jia-tao; ZHANG Xiu-li; LIANG Xin-miao

    2011-01-01

    An efficient preparative method was successfully developed for isolation and purification of unstable components from medicinal plant extracts, using a combined method of preparative high performance liquid chro matography(HPLC) and solid-phase extraction(SPE). The aim of this study was to obtain an effective method with high preparative efficiency and importantly to avoid the transformation of unstable compounds. The preparative HPLC system was based on an LC/MS controlled four-channel autopurification system. The SPE method was per formed with a C1s packing material to trap the target compounds and to remove the acidic additive derived from the mobile phase. Using this method, the unstable iridoid glucosides(IGs) as model compounds were successfully iso lated and purified from the extract of Hedyotis diffusa Willd. Six IGs(including one new minor IG) and one nucleo tide compound were simultaneously obtained, each with a purity of >91% as determined by HPLC. The structures of the isolated compounds were identified by UPLC/Q-TOF MS, UV, ID and/or 2D NMR. It was demonstrated that the combination of preparative HPLC with SPE is a versatile tool for preparative purification of unstable compounds from complex natural products.

  20. Simultaneous determination of triptolide, tripterifordin, celastrol and nine sesquiterpene alkaloids in Tripterygium preparations using high-performance liquid chromatography-triple quadrupole mass spectrometry.

    Science.gov (United States)

    Luo, Heng; Wu, Xia; Huang, Hao; Chen, Shuiying; Yang, Wei; Zhang, Lei; Cui, Hongmei; Yang, Jun; Yang, Andong

    2016-01-05

    Tripterygium wilfordii tablet (TWT) and Tripterygium hypoglaucum tablet (THT), the preparations of the two Tripterygium herbs, are well known for the treatment of rheumatoid arthritis and other related inflammatory diseases clinically. In the present study, a high performance liquid chromatography (HPLC) coupled with electrospray ionization (ESI) tandem triple quadrupole mass spectrometry (QQQ/MS) method was developed for simultaneous quantification of 12 chemical components in Tripterygium preparations. The fragmentation patterns of analytes using ESI and collision-induced dissociation (CID) techniques were reported. This assay method was validated with respect to linearity (r(2)>0.9991), precision, repeatability, and accuracy (recovery rate between 97.2 and 104.2%). The proposed method was successfully applied for simultaneous quantification of the 12 compounds in Tripterygium preparations from the different manufactures. In addition, to evaluate the quality of Tripterygium preparations, partial least square discrimination analysis (PLS-DA) was performed to differentiate the contents of 12 compounds. In conclusion, the established HPLC/QQQ/MS method was proven to be useful and efficient for quality control of Tripterygium preparations.