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Search Results: 1 - 10 of 75403 matches for " 燕远勇 "
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新型水溶性膦铑络合物催化烯烃的氢甲酰化反应研究
,左焕培
分子催化 , 1994,
Abstract: 新型水溶性膦铑络合物催化烯烃的氢甲酰化反应研究燕远勇,左焕培,金子林(大连理工大学化工学院,大连116012)关键词烯烃,水溶性膦铑络合催化剂,氢甲酰化,醛.1.前言为克服催化剂的流失和与反应产物的分离困难,近年来均相催化的一个重要进展是开发了以磺化...
2013年我国种植业化肥施用状况分析
杨帆,,姜义,,李荣,,孙钊
植物营养与肥料学报 , 2015, DOI: 10.11674/zwyf.2015.0124
Abstract: 【目的】我国农用化肥消费量大,数据来源不同,统计口径各异,行业内大多引用国家统计局公布的数据,但该数据无法推算出氮肥、磷肥、钾肥分类消费量。我国区域间、季节间、作物间化肥消费情况的报道很少,在调节化肥供需、指导化肥行业健康发展时显得依据不足。调查种植业化肥施用状况可以为指导肥料生产、供应提供重要依据。【方法】以农业部339个国家级基层肥料信息网点为依托,根据我国农业生产习惯和我国政府部门统计习惯,将一年分为三个用肥季,1~5月份为春耕季,6~8月份为夏播季,9~12月份为秋冬种季。在三个季节,每个网点随机调查30个农户的主要种植作物施用氮肥、磷肥、钾肥、复合(混)肥(包括配合式)量,经两级土壤肥料部门审核后,采用省份、相似种植区域、全国三级逐级加权平均的方法,推算了不同区域、不同季节、不同作物单位面积施肥量;再用作物单位面积施肥量、该作物全国种植总面积、样本中施肥面积占该作物种植面积的比例推算了作物全年、不同季节化肥施用量。同时,分析了主要作物、不同季节化肥施用状况以及供需平衡情况,不同季节、不同区域供肥情况和农民的购肥习惯。【结果】2013年我国种植业化肥施用量5498万吨(折纯下同),其中,氮肥(实物量)3382万吨,磷肥1175万吨,钾肥941万吨。粮食作物化肥总用量为2782万吨,占种植业化肥总用量的50.6%;其次是果树和蔬菜,三类作物占种植业化肥施用总量的82.8%,经济、园艺作物单位面积化肥施用量大于粮食作物。春耕、夏播、秋冬种化肥施用量分别占全年化肥施用量的34.2%、35.6%、30.2%。复混肥料和尿素是农民最常购买的两种肥料,从全年来看,农民施用复混肥料和尿素的样本数分别占总样本数的72.5%和71.6%,春耕、夏播、秋冬种农民购买尿素和复合(混)肥的样本数分别占该阶段样本数的70.9%和62.9%、84.9%和78.1%、56.6%和83.9%。春耕和夏播时期农民多数选用尿素,秋冬种多数选用复混肥料,东北、西北、华中南地区农民多选用尿素,华北、西南、华东地区农民多选用复混肥料。另外,我国氮肥、磷肥供应分别过剩1080万吨、680万吨,钾肥缺口370万吨,供需矛盾突出。氮、磷、钾养分配合式为15-15-15的复混肥样本数占农民选购复混肥总样本数的33.3%,说明复混肥养分结构不尽合理。【结论】建议国家进一步遏制氮肥、磷肥过剩产能,优化产品结构,大力推广科学施肥技术。
无机高分子钯络合物催化碘苯双羰化合成α-酮酰胺
金子林,,左焕培,B.Fell
催化学报 , 1993,
Abstract: ?
基因活化聚乳酸表面工程的初步研究
陈欣,,Cai,Kai-yong,蔡开,
重庆大学学报 , 2008,
Abstract: 运用层层自装(layer-by-layerself-assembly)技术,在聚乳酸表面形成半乳糖苷化的壳聚糖(galactosylatedchitosan,GC)/DNA多层膜结构,构建基因活化的生物材料.用接触角测试仪及紫外吸收光谱仪监控多层膜的组装过程及DNA的释放行为,倒置荧光显微镜观察HepG2细胞在GC/DNA多层膜修饰的聚乳酸表面的细胞形态及生长状态.结果表明:GC/DNA的交替吸收在聚乳酸表面形成了多层膜结构,DNA在PBS缓冲液(pH=7.4,37℃)中的释放可持续42h以上.黏附在多层膜修饰的聚乳酸表面的HepG2呈现纺锤样的细胞形态.另外,半乳糖是肝细胞表面无唾液酸糖蛋白的受体,从多层膜上释放出来的GC/DNA颗粒可被肝细胞特异识别并结合.
炒青石榴叶茶干燥工艺关键技术研究
安玉红,任廷,刘嘉,,
北方园艺 , 2014,
Abstract: 以青石榴叶为试材,参考现代化绿茶生产加工技术,对炒青石榴叶茶加工过程中干燥工艺主要关键技术进行了研究。结果表明干燥工艺对炒青石榴叶茶品质影响的主次顺序为烘二青温度>烘二青时间>炒干温度>炒三青时间>炒三青温度>炒干时间;炒青石榴叶茶产品最佳干燥工艺为烘二青温度85℃,烘二青时间15min,炒三青温度60℃,炒三青时间30min,炒干温度50℃,炒干时间2.5h。
TiO2/PtO-Pt复合膜和SnO2/PtO-Pt复合膜氢敏性能的研究
,杜雪岩,,郭洪猷,桂琳琳
化学学报 , 2003,
Abstract: 将PtO-Pt纳米粒子膜与TiO2,SnO2纳米粒子膜复合,利用PtO-Pt纳米粒子膜作为插入电极和催化剂,设计并研制出一类新型双层结构复合膜气体传感器。采用TEM和SEM对薄膜的显微结构进行了表征,对空气中4.0H2的氢敏性能研究表明200℃时,TiO2/PtO-Pt复合膜对氢气的灵敏度为70%,而TiO2纳米粒子膜无响应。100℃时,SnO2/PtO-Pt复合膜的灵敏度为92%,同样条件下,SnO2纳米粒子膜的灵敏度仅为4%。说明PtO-Pt纳米粒子膜的催化作用能够显著提高TiO2和SnO2的膜氢敏性能。另外,TiO2/PtO-Pt复合膜和SnO2/PtO-Pt复合膜均对空气中H2有很高的选择性。
基于AHP-FCE的遥感卫星系统覆盖效能评估
Coverage Effectiveness Evaluation of Remote Sensing Satellite System Based on AHP-FCE
 [PDF]

, 杨帆,
Geomatics Science and Technology (GST) , 2015, DOI: 10.12677/GST.2015.32007
Abstract:
针对遥感卫星系统的顶层设计与合理规划,建立科学的卫星系统覆盖能力评估模型具有重要意义。为此,建立了层次化的覆盖效能评估指标体系,采用层次分析法(AHP)设计指标权重;提出了一种新的覆盖特性仿真计算流程,基于模糊综合评判法(FCE)计算了评估指标的单因素模糊向量;最终提出了一个完整的基于AHP-FCE方法的遥感卫星系统覆盖效能评估技术流程,以多颗国内外典型遥感卫星进行了评估实验,验证了方法的有效性。
It is significant to establish a scientific coverage capability assessment model in the top-level de-signing and rational planning of remote sensing satellite system. The paper established a hierar-chical index system of coverage effectiveness evaluation, and the analytic hierarchy process (AHP) was used in index weights designing. Then, a new simulation computing process of coverage feature was proposed, and the fuzzy vector of index was calculated based on fuzzy comprehensive evaluation (FCE). Finally the paper put forward a complete effectiveness evaluation process of remote sensing satellite system based on AHP-FCE. Evaluation experiment using the typical do-mestic and foreign remote sensing satellites verified the effectiveness of the method.
以专业课程为载体融合培养“人才要素能力”与“专业能力”的教学模式的探索
Exploration of a Teaching Mode Using Professional Courses as Carriers to Integrate the Cultivation of Both Essential Competences and Professional Competences
 [PDF]

罗彦凤,, 蔡开,, 杨维虎, 刘鹏, 张吉喜
Creative Education Studies (CES) , 2019, DOI: 10.12677/CES.2019.74073
Abstract:
“人才要素能力”和“专业能力”是新一代大学生从容应对激烈竞争性与变动性行业选择和社会多样化需求,实现创新创业的必要能力。前者是人才从事任何活动的基本必要能力,也是人才进一步从事专业活动施展“专业能力”的基础。我们认为专业课程是培养学生“人才要素能力”和“专业能力”的一个重要载体。本文以《生物医用材料学》专业课程(本校生物工程专业和生物医学工程专业的必修课)为例,从教学内容、融合培养方法、教学效果评价等方面探索以专业课程为载体融合培养学生“人才要素能力”和“专业能力”的教学模式。该模式的建立和推广可望更有效地实现专业教育和大学教育目标。
Essential competences and professional competences are both indispensible for college students to deal with the selection by industries of fierce competition and instability, satisfy diverse social demands, and realize innovation and entrepreneurship. Essential competences are the basic abilities required for conducting any social activity and are also the basis for professional competences. We believe that professional courses should act as important carriers by which college students are trained with both essential competences and professional competences. By using Biomedical Materials Science (a required professional course for Bioengineering major and Biomedical Engineering Major in Chongqing University) as a model course, this paper explores a teaching mode to integrate the cultivation of both essential competences and professional competences from the aspects of teaching contents, teaching methods, teaching evaluation. The established mode may help realize the objectives of both specific professional education and general university education.
青花菜衰老过程中叶绿素降解相关基因的表达分析
樊艳,刘玉梅,李占省,方智,杨丽梅,庄木,张扬,孙培田
园艺学报 , 2015, DOI: 10.16420/j.issn.0513-353x.2015-0155
Abstract: 以两个耐贮性不同的青花菜高代自交系‘8554’和‘90196’为试验材料,分析其在贮藏过程中叶绿素含量的变化差异,利用实时荧光定量pcr技术对叶绿素降解相关基因的表达量进行研究。结果表明,在4℃贮藏期间,‘8554’和‘90196’的叶绿素含量均呈下降趋势,但耐贮藏材料‘8554’下降缓慢,且始终高于不耐贮材料‘90196’。boclh1(叶绿素酶1)的表达量变化在上述两种材料中表现一致,均只在初始时检测到较高表达,后期表达量很低。boclh2(叶绿素酶2)的表达量在‘8554’中变化较小,在‘90196’中变化较大,且高于‘8554’。bopph(脱镁叶绿素酶)在‘8554’中一直呈下降趋势,而在‘90196’中贮藏14d时有显著上升过程。bopao(脱镁叶绿酸a加氧酶)的表达量变化在二者中均有急剧增加的过程,但是在‘8554’中出现急剧增加的时期明显滞后于‘90196’。borccr(红色叶绿素代谢产物还原酶)在‘90196’中于贮藏21d时出现一个明显的表达高峰,而在‘8554’中未出现。上述结果表明耐贮藏性不同的青花菜叶绿素降解机制不同,其衰老过程中叶绿素含量的变化主要通过boclh2、bopph、bopao以及borccr的表达量变化来调节,boclh1主要在青花菜初始衰老中起降解叶绿素的作用。
棕榈油研究现况和进展
Research Status and Progress of Palm Oil
 [PDF]

, 戴智勇,
Hans Journal of Food and Nutrition Science (HJFNS) , 2014, DOI: 10.12677/HJFNS.2014.31002
Abstract:
棕榈油又称棕油、棕皮油,是从油棕树上棕果的果皮中榨取出来的油脂,为不干性油,是植物油的一种;棕榈油中饱和脂肪酸和不饱和脂肪酸的比例接近于1:1,主要含有棕榈酸(C16)和油酸(C18)两种最普通的脂肪酸,棕榈油还含有丰富的β-胡萝卜素、维生素A和维生素E。人体对棕榈油的消化和吸收率超过97%,和其他所有植物食用油一样,棕榈油本身不含有胆固醇。棕榈油资源丰富,具有抗氧化性、抗癌作用、降低胆固醇和抗糖尿病等生理功能,开发利用前景广阔
Palm oil as a kind of non-drying oil, (also known as dendê oil, from Portuguese) is an edible vegetable oil derived from the mesocarp (reddish pulp) of the fruit of the oil palms. Palm oil contains saturated and unsaturated fatty acids in the ratio of nearly 1:1 and mainly in the forms of palmitic acid (C16) and oleic acid (C18), which are two kinds of the most common fatty acids. In addition, palm oil is also rich in beta carotene, vitamin A and vitamin E. The absorption and digestion rate of palm oil in human body are more than 97%. Like all vegetable oils, palm oil does not contain cholesterol. Palm oil can be derived from extensive resources, and the physiological functions are also formidable, including anti-oxidation, anti-cancer, lowering cholesterol and anti-diabetes, etc. Therefore, the development and utilization of palm oil in the commercial food industry around the world are buoyed and have broad market prospects.
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