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润滑油 2011年第2期26卷 30-35页

作者： joan Souchik Evonik RohMax USA

Pour point depressants(PPDs),also know as wax crystal modifiers,are polymeric materials that when added to a mineral based lubricant can significantly improve the low temperature low shear properties or pumpability of an *** many years the lubricant industry has set requirements for pumpability of engine oils,with the most well known requirement being the ASTM D4684 MRV TP-1 specification within SAE *** has gone a step further in their GF-4 and GF-5 specifications by requiring these generations of oil to be tested for pumpability after severe *** the number and severity of pumpability tests increase the need for proper PPD selection becomes very *** paper will present a brief history of pumpability and the tests used to measure low temperature shear viscosity,including the new ROBO test for aged *** will be presented to show that,with proper PPD selection,an oil can easily be formulated to meet all the low temperature low shear requirements of SAE and ILSAC.

关键词： PPD ROBO MRV TP-1

An evaluation of mass,number concentration,chemical composition and types of particles in a cafeteria before and after the passage of an antismoking law

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Particuology 2013年第5期11卷 527-532页

作者： jorge Pey Barend L.van Drooge Anna Ripollb Teresa Moreno joan O.Grimalt Xavier Querol Andres Alastuey Department of Epidemiology Lazio Regionvia S.Costanza5300198 RomeItaly Institute of Environmental Assessment and Water Research.ID/EA-CSIC C/Jordi Girona.18-2608034 BarcelonaSpain

This study assessed air quality indicators before and after enactment of the Spanish anti-smoking law. Mass and number concentrations and the chemical composition of particles were evaluated. Microscopy analyses were also conducted. Real time concentrations of PMlo, PM2.s, PM1 and ultrafine particles were measured under ventilated and non-ventilated conditions and PMlo samples were collected for detailed inorganic and organic chemical characterization. Before enactment of the law in 2010, tobacco smoke produced significant indoor ambient particulate matter pollution, with elevated particulate matter mass concentrations （PM10 and PM1 concentrations of 122-220 and 48-85 Dg/m3, respectively） and ultrafine particle numbers （75,000 and 48,000 cm ~ under ventilated and non-ventilated conditions, respectively）. Typical tobacco smoke tracers including iso- and anteiso-alkanes and elements including La and Ce from the ignition of lighters were abundant. Additionally, several toxic substances derived from tobacco smoke, including Cd （3.1 ng/m3） and benzo[a]pyrene （1.0 ng/m3） were present at concentrations approximately 10 times greater than those measured after enactment of the anti-smoking law. The anti-smoking law sig- nificantly reduced exposure to potentially toxic compounds by approximately 90%. This law is expected to have a positive health impact, particularly for people who spend considerable time in affected envi- ronments, such as employees.

关键词： Indoor airParticulate matterUltrafine particlesNucleationCoagulation-condensationEnvironmental tobacco smoke

The influence of the capping ligands on the optoelectronic performance,morphology,and ion liberation of CsPbBr_(3)perovskite quantum dots

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Nano Research 2023年第7期16卷 10626-10633页

作者： Yongfeng Liu Shi Tang Zhaoju Gao Xiuwen Shao Xiaolin Zhu joan Ràfols Ribé Thomas Wågberg Ludvig Edman jia Wang College of Physical Science and Technology Yangzhou UniversityYangzhou 225002China Department of Physics UmeåUniversityUmeåSE-90187Sweden LunaLEC AB UmeåSE-90187Sweden Microelectronics Industry Research Institute Yangzhou UniversityYangzhou 225002China

Perovskite quantum dots(PeQDs)endowed with capping ligands exhibit impressive optoelectronic properties and enable for costefficient solution processing and exciting application *** synthesize and characterize three different PeQDs with the same cubic CsPbBr_(3)core,but which are distinguished by the ligand composition and ***-1 features a binary didodecyldimethylammonium bromide(DDAB)and octanoic acid capping ligand system,with a high surface density of 1.53 nm^(-2),whereas PeQD-2 and PeQD-3 are coated by solely DDAB at a gradually lower surface *** show that PeQD-1 endowed with highest ligand density features the highest dispersibility in toluene of 150 g/L,the highest photoluminescence quantum yield of 95%in dilute solution and 59%in a neat film,and the largest core-to-core spacing in neat thin *** further establish that ions are released from the core of PeQD-1 when it is exposed to an electric field,although it comprises a dense coating of one capping ligand per four surface core *** finally exploit these combined findings to the development of a light-emitting electrochemical cell(LEC),where the active layer is composed solely of solution-processed pure PeQDs,without additional *** this device,the ion release is utilized as an advantage for the electrochemical doping process and efficient emissive operation of the LEC.

关键词： CsPbBr_(3)quantum dots capping ligand ion liberation light-emitting electrochemical cell

Biofunctionalized all-polymer photonic lab on a chip with integrated solid-state light emitter

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Light(Science & Applications) 2015年第1期4卷 430-437页

作者： Andreu Llobera joan juvert Alfredo Gonzalez-Fernandez Bergoi Ibarlucea Ester Carregal-Romero Stephanus Buttgenbach Cesar Fernandez-Sanchez Instituto de Microelectronica de Barcelona IMB-CNM(CSIC) Campus UAB08193 BellaterraSpain Institut fur Mikrotechnik Technische Universitat BraunschweigBraunschweig 38106Germany

A photonic lab on a chip(PhLOC),comprising a solid-state light emitter(SSLE)aligned with a biofunctionalized optofluidic multiple internal reflection(MIR)system,is *** SSLE is obtained by filling a microfluidic structure with a phenyltrimethoxysilane(PhTMOS)aqueous sol solution containing a fluorophore organic *** curing,the resulting xerogel solid structure retains the emitting properties of the fluorophore,which is evenly distributed in the xerogel *** studies demonstrate that after a total dose(at λ5365 nm)greater than 24 j cm^(-2),the xerogel emission decay is only 4.1%.To re-direct the emitted light,the SSLE includes two sets of air mirrors that surround the *** mapping of the SSLE demonstrates that alignment variations of 150 mm(between the SSLE and the external pumping light source)provide fluctuations in emitted light smaller than 5%.After this verification,the SSLE is monolithically implemented with a MIR,forming the *** performance is assessed by measuring quinolone yellow,obtaining a limit of detection(LOD)of(0.6060.01)***,the MIR is selectively biofunctionalized with horseradish peroxidase(HRP)for the detection of hydrogen peroxide(H_(2)O_(2))target analyte,obtaining a LOD of(0.760.1)μM for H_(2)O_(2),confirming,for the first time,that solid-state xerogel-based emitters can be massively implemented in biofunctionalized PhLOCs.

关键词： medical devices photonic lab on a chip polymer technology solid-state light emitters sol–gel

The characterization and dissolution performances of spray dried solid dispersion of ketoprofen in hydrophilic carriers

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Asian journal of Pharmaceutical Sciences 2015年第5期10卷 372-385页

作者： Siok-Yee Chan Yin-Ying Chung Xin-Zi Cheah Eryn Yen-Ling Tan joan Quah School of Pharmaceutical Sciences Universiti Sains Malaysia11800 Pulau PinangMalaysia

Solid dispersion is one of the most promising strategies to improve oral bioavailability of poorly soluble ***,there are inconsistent dissolution performances of solid dispersion reported which entails further *** this study,solid dispersions of ketoprofen in three hydrophilic carriers,*** K30,PVPVA 6:4 and PVA were prepared and *** characterization of the physical mixture of ketoprofen and carriers shows certain extent of amorphization of the *** result is coinciding to evaluation of drug-polymer interaction using ATR-FTIR whereby higher amorphization was seen in samples with higher drug-polymer *** scanning confirms that fully amorphous solid dispersion was obtained for SD KTP PVP K30 and PVPVA system whereas partially crystalline system was obtained for SD KTP ***,dissolution profiles of the solid dispersion had shown that degree of amorphization of KTP was not directly proportional to the dissolution rate enhancement of the solid dispersion ***,it is concluded that complete amorphization does not guarantee dissolution enhancement of an amorphous solid dispersion system.

关键词： Solid dispersion Amorphous Polymer PVP PVPVA ketoprofen

Tanning capacityof Tessmannia burttii extracts:thepotentialeco-friendlytanning agents fortheleatherindustry

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journal of Leather Science and Engineering 2021年第1期3卷 149-157页

作者： Cecilia R.China Stephen S.Nyandoro joan j.E.Munissi Mihayo M.Maguta Michael Meyer Michaela Schroepfer Division of Textile and Leather Technologies Tanzania Industrial Research and Development OrganizationP.O.Box 2355Dar es SalaamTanzania Chemistry Department College of Natural and Applied SciencesUniversity of Dar es SalamP.O.Box 35061Dar es SalaamTanzania Department of Environmental Planning Institute of Rural Development Planning(IRDP)P.O.Box 138DodomaTanzania FILK-Research Institute of Leather and Plastic Sheeting Meißner Ring 1-509599 FreibergGermany

In the present study,the tannins from stem and root barks of Tessmannia burttii Harms(Caesalpiniaceae),a plant species abundantly growing in Tanzania and other parts of Africa,were investigated for their suitability in hides *** powder was extracted at selected temperatures(30,50 and 80°C)and the influence of each temperature on the crosslinking capacity was *** interaction mechanism between hide powder collagen and the tannins was studied by Differential Scanning Calorimetry(DSC),trinitrobenzensulfonic(TNBS)acid assay and amino acid hydrolysis *** temperatures showed low influence on crosslinking capacity of the ***,extract obtained at 50°C exhibited best performance in terms of gap size between T onset and T *** stem bark extract yield was higher than that from the root bark,but both were within the recommended *** tannin content(61%)of *** stem bark extract was above recommended value(10%),whereas its total phenolic content and total flavonoic content were found to be above that of commercial Acacia mearnsii *** study of cross-linking parameters as a function of pH showed cross-linking to occur via a covalent mechanism at the basic amino ***,the bonds were not resistant to acid *** observed interaction mechanism indicated that tannins from stem and root barks of *** belong to the condensed tannin,similar to ***(black wattle),a commercial tannin source that was used in this study as a *** from this study depict that *** extracts are auspicious eco-friendly alternative source of vegetable tannins to overcome the use of chromium salts in the leather industry.

关键词： Tessmannia burttii Caesalpiniaceae Leather industry Vegetable tanning Tanning capacity

A Comparison of Value Elicitation Question Formats in Multiple-Good Contingent Valuation

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Frontiers of Economics in China-Selected Publications from Chinese Universities 2014年第1期9卷 85-108页

作者： Chih-Chen Liu joseph A. Herriges C. L. Kling Silvia Secchi joan I. Nassauer Daniel j. Phaneuf Department of Applied Economics National University of Kaohsiung Kaohsiung 81148Taiwan China Department of Economics Iowa State University Ames IA 50011 USA Department of Agribusiness Economics Southern Illinois University Carbondale IL 62901USA School of Natural Resources and Environment University of Michigan Ann Arbor M148103USA Department of Agricultural and Applied Economics University of Wisconsin Madison WI53706 USA

This paper provides a convergent validity test of two types of multinomial choice questions vis-a-vis a dichotomous choice question by formally testing whether these stated preference elicitation question formats provide comparable welfare estimates. In particular, a dichotomous choice question, a traditional multinomial choice question, and a modified multinomial choice question suggested by Carson and Groves （2007） were applied in split samples to assess the influence of the informational and incentive properties on the respondents＇ annual willingness to accept compensation for adopting costly conservation practices in agriculture that benefit the environment. Our findings suggest that the two multinomial choice question formats elicit a similar mean willingness to accept distributions, but they are both different from a standarddichotomous choice question. Further, the willingness to accept distributions derived from the multinomial choice question formats are more dispersed than those from the dichotomous choice question.

关键词： stated preference choice experiment dichotomous choice,incentive compatibility multinomial choice

Feasibility of using pedometers in a state-based surveillance system：2014 Arizona Behavioral Risk Factor Surveillance System

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journal of Sport and Health Science 2018年第1期7卷 34-41页

作者： Alberto Flórez-Pregonero janet E.Fulton joan M.Dorn Barbara E.Ainsworth School of Nutrition and Health Promotion College of Health Solutions Arizona State University Phoenix AZ 85004 USA Pontificia Universidad javeriana Bogot6 110231 Colombia Physical Activity and Health Branch Division of Nutrition Physical Activity and Obesity Center for Chronic Disease Prevention and Health Promotion U.S. Centers for Disease Control and Prevention Atlanta GA 30340 USA Department of Community Health and Social Medicine City University of New York (CUNY) School of Medicine New York NY 10031 USA

Background: Despite their utility in accessing ambulatory movement, pedometers have not been used consistently to monitor physical activity in U.S. surveillance systems. This study was designed to determine the feasibility of using pedometers to assess daily steps taken in a sub-sample of adults from Maricopa County who completed the 2014 Arizona Behavioral Risk Factor Surveillance System ***: Respondents were sent an Omron Hj324 U pedometer, a logbook to record steps taken, and a walking questionnaire. The pedometer was worn for 7 days. Feasibility was assessed for acceptability(interest in study), demand(procedures followed correctly), implementation(time to complete study), and practicality(cost).Results: Acceptability was modest with 23.9%(830/3476) agreeing to participate. Among those participating(92.9%; 771/830), 50.1%(386/771)returned the logbook. Demand was modest with 39.3%(303/771) of logbooks returned with valid data. Implementation represented 5 months to recruit participants. The cost to obtain valid step-count data was USD61.60 per person. An average of 6363 ± 3049 steps/day were taken with most participants classified as sedentary(36.0%) or low active(35.6%).Conclusion: The feasibility of using pedometers in a state-based surveillance system is modest at best. Feasibility may potentially be improved with easy-to-use pedometers where data can be electronically downloaded.

关键词： Assessment Measurement Physical activity Public health

Empowering youth sport environments: Implications for daily moderate-to-vigorous physical activity and adiposity

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journal of Sport and Health Science 2017年第4期6卷 423-433页

作者： Sally A.M. Fenton joan L. Duda Paul R. Appleton Timothy G. Barrett School of Sport Exercise and Rehabilitation Sciences University of Birmingham Edgbaston Birmingham B15 2TT UK School of Clinical and Experimental Medicine University of Birmingham Edgbaston Birmingham B15 2TT UK

Background: Evidence suggests involvement in youth sport does not guarantee daily guidelines for moderate-to-vigorous physical activity(MVPA) are met, and participation may not mitigate the risks associated with physical inactivity. The need to promote higher habitual MVPA engagement amongst children active in the youth sport context has therefore been underlined. Framed by self-determination theory, the aim of the present study was to examine the implications of the motivational climate created in youth sport, for children's daily engagement in MVPA and associated adiposity. Specifically, we sought to test a motivational sequence in which children's perceptions of an empowering coach-created motivational climate were related to autonomous and controlled motivation, which in turn predicted sport-related enjoyment. Finally, enjoyment was assumed to predict accelerometer assessed daily MVPA and, following this, ***: Male and female youth sport participants aged 9–16 years(n = 112) completed multi-section questionnaires assessing their perceptions of the motivational climate created in youth sport(i.e., autonomy supportive, task involving, socially supportive), autonomous and controlled motivation, and sport-related enjoyment. Daily MVPA engagement was determined via 7 days of accelerometry. Percent body fat(BF%) was estimated using bio-electrical impedance ***: Path analysis revealed perceptions of an empowering motivational climate positively predicted players' autonomous motivation, and in turn, sport-related enjoyment. Enjoyment was also significantly negatively related to players' BF%, via a positive association with daily ***: Fostering more empowering youth sport environments may hold implications for the prevention of excess adiposity, through encouraging higher habitual MVPA engagement. Findings may inform the optimal design of youth sport settings for MVPA promotion, and contribute towards associated healthy weight maint

关键词： Accelerometry Exercise psychology Moderate-to-vigorous physical activity Motivation Obesity Self-determination theory Youth sport

Exercise-induced hypoalgesia in chronic neck pain: A narrative review

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Sports Medicine and Health Science 2024年第1期6卷 37-47页

作者： Fernando Rojas-Galleguillos Cecilia Clark-Hormazabal Eduardo Mendez-Fuentes Francisco Guede-Rojas Cristhian Mendoza Andres Riveros Valdes Claudio carvajal-Parodi Universidad San Sebastian Programa Magíster en Kinesiología MusculoesqueleticaLientur#1457ConcepcionChile Exercise and Rehabilitation Sciences Laboratory School of Physical TherapyFaculty of Rehabilitation SciencesUniversidad Andres BelloSantiago7591538Chile Universidad San Sebastian Laboratoriode NeurobiologíFacultad de Odontologíay Ciencias dela RehabilitacionLientur#1457ConcepcionChile Universidad San Sebastian Departamento de Ciencias MorfologicasFacultad de MedicinaCienciaLientur#1457ConcepcionChile Universidad San Sebastian Escuelade KinesiologíaFacultad de OdontologíaCiencias dela RehabilitacionLientur#1457ConcepcionChile

Chronic neck pain(CNP)is a worldwide health problem with several risk *** of the most widely used treatments for managing this condition is therapeutic exercise,which could generate a response called exerciseinduced hypoalgesia(EIH).There is no consensus on the best exercise modality to induce ***,this review aims to analyze and synthesize the state-of-the-art about the hypoalgesic effect of exercise in subjects with *** included articles on EIH and CNP in patients older than 18 years,with pain for more than three months,where the EIH response was *** that studied CNP associated with comorbidities or measured the response to treatments other than exercise were *** studies reviewed reported variable *** in healthy subjects has been shown to reduce indicators of pain sensitivity;however,in people with chronic pain,the response is *** investigations reported adverse effects with increased pain intensity and decreased pain sensitivity,others found no clinical response,and some even reported EIH with decreased pain and increased *** is an identifiable,stimulable,and helpful therapeutic response in people with *** research is still needed on subjects with CNP to clarify the protocols and therapeutic variables that facilitate the EIH *** addition,it is necessary to deepen the knowledge of the intrinsic and extrinsic factors that influence EIH in people with CNP.

关键词： Exercise-induced hypoalgesia Neck pain Chronic pain Neck exercise therapy