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Sample records for alkines

  1. A Bibliometric Analysis of the Academic Influences of and on Evaluation Theorists' Published Works

    Science.gov (United States)

    Heberger, Anne E.; Christie, Christina A.; Alkin, Marvin C.

    2010-01-01

    As is the case with other fields, there is motivation for studying the impact that the body of evaluation theory literature has within and outside the field. The authors used journal articles written by theorists included on the evaluation theory tree by Alkin and Christie (2004; Christie & Alkin, 2008) and published in the Web of Science, an…

  2. How Analogue Research Can Advance Descriptive Evaluation Theory: Understanding (and Improving) Stakeholder Dialogue

    Science.gov (United States)

    Campbell, Bernadette; Mark, Melvin M.

    2015-01-01

    Evaluation theories can be tested in various ways. One approach, the experimental analogue study, is described and illustrated in this article. The approach is presented as a method worthy to use in the pursuit of what Alkin and others have called descriptive evaluation theory. Drawing on analogue studies conducted by the first author, we…

  3. Comparing evaluation activities across multiple theories of practice.

    Science.gov (United States)

    Dillman, Lisa M

    2013-06-01

    This article compares and contrasts the evaluation activities described in Practical Participatory Evaluation (Cousins & Whitmore, 1998), Values-engaged Evaluation (Greene, 2005), and Emergent Realist Evaluation (Mark, Henry, & Julnes, 1998). Using the logic models developed to depict each of the three evaluation theories (Hansen, Alkin, & Wallace, 2013) as a starting point, both quantitative and qualitative analysis techniques are employed to discuss the similarities and differences across the practice prescriptions. The approaches are then described according to Miller's (2010) standards for empirical examinations of evaluation theory. Specifically, I offer speculation about their operational specificity and feasibility in practice. I argue that none of the models is completely specific, or wholly unique, and they all present challenges of adaptation into the field. However, the models each offer varying degrees of guidance and unique elements through their prescriptions.

  4. Tempo-spatial variation of emission inventories of speciated volatile organic compounds from on-road vehicles in China

    Directory of Open Access Journals (Sweden)

    H. Cai

    2009-05-01

    Full Text Available Emission inventories of sixty-nine speciated non-methane volatile organic compounds (NMVOC from on-road vehicles in China were estimated for the period of 1980–2005, using seven NMVOC emission profiles, which were summarized based on local and international measurements from published literatures dealing with specific vehicle categories running under particular modes.

    Results show an exponential growth trend of China's historical emissions of alkanes, alkenes, alkines, aromatics and carbonyls during the period of 1980–2005, increasing from 63.9, 39.3, 6.9, 36.8 and 24.1 thousand tons, respectively, in 1980 to 2781.4, 1244.9, 178.5, 1350.7 and 403.3 thousand tons, respectively, in 2005, which coincided well with China's economic growth. Emission inventories of alkenes, aromatics and carbonyls were gridded at a high resolution of 40 km×40 km for air quality simulation and health risk evaluation, using the geographic information system (GIS methodology. Spatial distribution of speciated NMVOC emissions shows a clear difference in emission densities between developed eastern and relatively underdeveloped western and inland China. Besides, the appearance and expansion of high-emission areas was another notable characteristic of spatial distribution of speciated NMVOC emissions during the period.

    Emission contributions of vehicle categories to speciated NMVOC groups showed annual variation, due to the variance in the provincial emissions and in the relative fractions of the seven emission profiles adopted at the provincial level. Highly reactive and toxic compounds accounted for high proportions of emissions of speciated NMVOC groups. The most abundant compounds were isopentane, pentane and butane from alkanes; ethene, propene, 2-methyl-2-butene and ethyne from alkenes and alkines; benzene, toluene, ethylbenzene, o-xylene, and m,p-xylene (BTEX and 1,2,4-trimethylbenzene from aromatics and formaldehyde, acetaldehyde

  5. Tempo-spatial variation of emission inventories of speciated volatile organic compounds from on-road vehicles in China

    Directory of Open Access Journals (Sweden)

    H. Cai

    2009-09-01

    Full Text Available Emission inventories of sixty-seven speciated non-methane volatile organic compounds (NMVOC from on-road vehicles in China were estimated for the period of 1980–2005, using seven NMVOC emission profiles, which were summarized based on local and international measurements from published literatures dealing with specific vehicle categories running under particular modes.

    Results show an exponential growth trend of China's historical emissions of alkanes, alkenes, alkines, aromatics and carbonyls during the period of 1980–2005, increasing from 63.9, 39.3, 6.9, 36.8 and 24.1 thousand tons, respectively, in 1980 to 2778.2, 1244.5, 178.7, 1351.7 and 406.0 thousand tons, respectively, in 2005, which coincided well with China's economic growth. Emission inventories of alkenes, aromatics and carbonyls were gridded at a high resolution of 40 km×40 km for air quality simulation and health risk evaluation, using the geographic information system (GIS methodology. Spatial distribution of speciated NMVOC emissions shows a clear difference in emission densities between developed eastern and relatively underdeveloped western and inland China. Besides, the appearance and expansion of high-emission areas was another notable characteristic of spatial distribution of speciated NMVOC emissions during the period.

    Emission contributions of vehicle categories to speciated NMVOC groups showed annual variation, due to the variance in the provincial emissions and in the relative fractions of the seven emission profiles adopted at the provincial level. Highly reactive and toxic compounds accounted for high proportions of emissions of speciated NMVOC groups. The most abundant compounds were isopentane, pentane and butane from alkanes; ethene, propene, 2-methyl-2-butene and ethyne from alkenes and alkines; benzene, toluene, ethylbenzene, o-xylene, and m,p-xylene (BTEX and 1,2,4-trimethylbenzene from aromatics and formaldehyde, acetaldehyde

  6. L—ADDER课程分级评估工具的研究

    Institute of Scientific and Technical Information of China (English)

    陈瑾

    2016-01-01

    阿尔金(Alkin,M.C.)将课程评价划分为两类:课程产品评价和课程方案评价。课程产品包括课程的有形产物,如课程纲要、课程标准、教科书等;课程方案是指处于运作状态下的课程,注重对课程与其所处环境条件的交互作用的分析。课程产品评价是静态意义上的课程评价。动态意义上的课程评价内在地包含了静态的课程文本评价。或者说,静态的课程文本也只有纳入到动态观下加以审视,才能给予全面深入的评价。上海市黄浦区卢湾二中心小学以动态观为指导,研制L-ADDER课程评估工具,充分

  7. Role of biology in the air–sea carbon flux in the Bay of Bengal and Arabian Sea

    Indian Academy of Sciences (India)

    M K Sharada; P S Swathi; K S Yajnik; C Kalyani Devasena

    2008-08-01

    A physical-biological-chemical model (PBCM)is used for investigating the seasonal cycle of air –sea carbon flux and for assessing the effect of the biological processes on seasonal time scale in the Arabian Sea (AS)and Bay of Bengal (BoB),where the surface waters are subjected to contrasting physical conditions.The formulation of PBCM is given in Swathi et al (2000),and evaluation of several ammonium-inhibited nitrate uptake models is given in Sharada et al (2005). The PBCM is here first evaluated against JGOFS data on surface pCO2 in AS, Bay of Bengal Process Studies (BoBPS)data on column integrated primary productivity in BoB,and WOCE I1 data on dissolved inorganic carbon (DIC)and alkalinity (ALK)in the upper 500 meters at 9°N in AS and at 10°N in BoB in September –October.There is good qualitative agreement with local quantitative discrepancies. The net effect of biological processes on air –sea carbon flux on seasonal time scale is determined with an auxiliary computational experiment,called the abiotic run,in which the biological processes are turned off.The difference between the biotic run and abiotic run is interpreted as the net effect of biological processes on the seasonal variability of chemical variables.The net biological effect on air –sea carbon flux is found to be highest in southwest monsoon season in the northwest AS, where strong upwelling drives intense new production.The biological effect is larger in AS than in BoB,as seasonal upwelling and mixing are strong in AS,especially in the northeast,while coastal upwelling and mixing are weak in BoB.

  8. Inflnence of formaldehyde/melamine ratio on properties of melmine-formaldehyde foam%甲醛/三聚氰胺配比对三聚氰胺甲醛泡沫塑料性能的影响研究

    Institute of Scientific and Technical Information of China (English)

    孙瑞朋; 金铁玲; 储富祥; 王春鹏

    2011-01-01

    三聚氰胺和甲醛在温度为85-95℃,氢氧化钠为催化剂、持续反应3-4h的条件下,可反应生成一种固含量≥65%、化学性能相对稳定的三聚氰胺甲醛树脂.以这种树脂为基体,加入乳化剂、固化剂和发泡剂,经发泡工艺制备出三聚氰胺甲醛泡沫塑料.研究了甲醛/三聚氰胺的摩尔配比(F/M)对可发性三聚氰胺甲醉树脂的物理性能、有毒物质残余量、机械性能的影响,以及与树脂可发性的关系.结果表明,当F/M=3.0时,可发性三聚氰胺甲醛树脂的固含量为69%;黏度为1 280 mPa·s;抗弯曲强度为305.6 kPa;氧指数为40.5%;热释放速率为0.15 kW/m2;烟灰产率仅为2.1 m2/m2 ;峰值CO产量为0.0292 kg/kg.%The foamable melamine resin is prepared from formaldehyde, paraformaldehyde and melamine at the temperature of 85℃ - 95℃, using alkine catalyst , by gradually copolymerization for 3 h. The solid content of the resin is over 80% and the chemical properties of the resin is stable. The vesicant,foam emulsifier and the curing agent are used to mixed with the foamable melamine resin to prepare melamine foam. By analyzing the formaldehyde/melamine ratio ( molar ratio) ,the foam structure,the mechanical properties , and the flame-retardant performance of the melamine foam are researched. The result showed that when the molar ratio of formaldehyde to melamine is 3.0, the melamine foam is dense and uniform. The solide content is 69%; viscosity is 1280 mPa·s; bending strength is 305.6 kPa ; oxygen index is 40. 5 ; heat release rate is 0.15 kW/m2 ; total smoke release is 2.1 m2/m2 ; peak carbon monoxide yield is 0.65 kg/kg.

  9. 內容探勘技術在教育評鑑研究發展趨勢分析之應用 The Application of Content Mining Techniques to the Analysis of Educational Evaluation Research Trends

    Directory of Open Access Journals (Sweden)

    曾元顯 Yuen-Hsien Tseng

    2011-03-01

    the evaluation methods, the studies conducted by Chen, Weiss, and Rossi are identified as newer ones than those by Cook and Compbell, which coincides with the fact shown in the evaluation theory tree (a sort of topical tree organized by Marvin Alkin, an experienced expert in the field. Besides, with this topic trend analysis, it is also found that the number of papers dealing with the major research topics seems to be decreasing. However, all these results need to be interpreted by domain experts to reveal their true meanings. The methodology presented in this research may be applied not only to improve the efficiency of content analysis, but also to facilitate regular tracing of topic evolution, to spot the positions of important researchers in the field, and therefore to provide relevant clues or materials for further studies.

  10. 慢性肾脏病患者活性维生素D3缺乏及其原因探讨%The causes for low vitamin D3 in chronic kidney diseases patients

    Institute of Scientific and Technical Information of China (English)

    王瑞; 邢昌赢; 李旻; 李婷; 毛慧娟; 孙彬; 俞香宝; 胡建明; 钱军; 赵秀芬

    2011-01-01

    目的:观察慢性肾脏病(chronic kidney disease,CKD)患者活性维生素D3水平以及探讨25(OH)D3缺乏的原因.方法:对174例住院CKD患者的临床资料进行前瞻性研究.测定血清25(OH)D3水平、空腹血糖(FBG)、空腹胰岛素(FINS)及C肽(CP),并常规检测Ser、BUN、碱性磷酸酶(ALP)、白蛋白(Alb),血清钙、磷,全段甲状旁腺激素(iPTH)、C反应蛋白(CRP)、24 h尿蛋白等.根据25(OH)D3水平将CKD患者分三组,A组25(OH)D350 nmol/L(n=12),比较各组间差异.分析CKD患者25(OH)D3与各临床指标的关系.结果:非透析患者25(OH)D3水平不足占93.3%,其中25(OH)D3严重缺乏占24.2%.透析患者25(OH)D3不足的占95.8%,严重缺乏占39.1%.C组Alb和Ca2+明显高于A、B组,C组尿蛋白和Scr与A、B组有明显减低(P0.05).多元线性回归分析结果显示,25(OH)D3与尿蛋白、Scr和CP呈负相关,与Alb呈正相关.结论:慢性肾脏病中维生素D不足和缺乏普遍存在,大量蛋白尿和高C肽是维生素D不足和缺乏的高危因素.Alb、尿蛋白、高C肽是影响维生素D水平的重要因素之一.%Objective: To investigate the magnitude of vitamin D deficiency and the causes of the low vitamin D in CKD patients. Methods: Clinical data of 174 inpatients with CKD was analyzed retrospectively. Level of 25(OH)D3 in these patients, as well as the levels of fasting blood glucose (FBG), fasting insulin (FINS) and serum C-peptide(CP), serum cereati-nine (Scr), urea nitrogen (BUN), serum alkine phosphates(ALP), albumin (Alb), serum calcium (Ca) and blood serum P (P), intact parathyroid hormone (iPTH), C reactive protein (CRP), 24 h urine protein, etc were examined. According to 25(OH)D3 levels of CKD, patients were divided into three groups, group A 25(OH)D3<25 nmol/L (n=47), group B 25(OH)D3 25-50 nmol/L (n=115) and group C 25(OH)D3>50 nmol/L (n=12). Correlation between 25(OH)D3 and parameters was analyzed. Results: In the predialysis patients, the prevalence of 25 (0H)D3