oalib

Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99

Submit

Any time

2019 ( 20 )

2018 ( 453 )

2017 ( 506 )

2016 ( 490 )

Custom range...

Search Results: 1 - 10 of 24831 matches for " 卞凤娇 "
All listed articles are free for downloading (OA Articles)
Page 1 /24831
Display every page Item
改进致动面模型的多风力机尾流研究
,徐宇,王强,宋娟娟,徐建中
工程热物理学报 , 2015,
Abstract: 致动模型是一种较新的CFD计算模型,通过在N-S方程添加源项的形式模拟叶片对流场的作用,减少了网格数量和计算时间。本文结合面元法在致动模型上提出一种改进致动面模型,并在OpenFoam平台对改进致动面模型进行尾流预测,数值研究了NRELPhaseVI水平轴风力机在均匀来流中的流场特性,对垂直和错排两种排布方式下的多风机尾流流场特性作出分析,如涡结构、速度亏损、尾迹干涉等,为深入研究风力机尾流以及风场开发提供了一定的\linebreak依据。
子宫内膜异位症合并输卵管闭孔疝1例

王亚楠,马鹏程,冯文娟,王倩,,张迎春
- , 2017, DOI: 10.6040/j.issn.1671-7554.0.2017.744
Abstract:
深圳市高收入人群膳食结构与代谢综合征关系
朱翠,苏环,刘颜,张献共,李红艳,陈恒,韩薇
中国公共卫生 , 2007, DOI: 10.11847/zgggws2007-23-08-27
Abstract: ?目的探讨深圳市高收入人群的膳食结构特点、饮食行为习惯以及代谢综合征(MS)的现患状况.方法对2004年9月~2005年8月到北大深圳医院特诊科1515名体检者进行分析,对患有MS或其高危症状的500名调查对象进行3d24h膳食结构和饮食行为习惯调查.结果受检者MS的患病率为13.07%.膳食结构:平均每人每日能量摄入量为9.63MJ为中国营养学会推荐膳食供给量(RDA)的102%,外出就餐时能量摄入量为RDA的115.5%.碳水化合物、核黄素和硫胺素的摄入量都显著低于RDA水平;动物来源的蛋白质和油脂的摄入量都显著高于RDA水平.大部分调查对象都有经常熬夜、暴饮暴食;经常出差、饮食不规律等与MS密切相关的不良饮食行为习惯.结论深圳市高收入人群MS的患病率明显增高.该人群膳食结构不合理和不良的饮食行为习惯是MS高患病率的主要因素.加大对深圳市高收入人群健康教育工作力度,对MS及心血管并发症的防治具有重要意义.
激光辐照金属丝产生电子束的发散度
陈实,
强激光与粒子束 , 2012,
Abstract: ?研究了激光辐照金属丝产生电子束的自身磁场对其发散度的影响。通过理论分析和量级估算得到:电子在金属丝附近运动时,同时受到金属丝电场和自身磁场的作用,聚集效应明显;当电子离开金属丝后,空间电荷效应的库仑排斥作用与自身磁场的聚集作用量级相当,近似认为可以保持已经具有的发散度。利用经典轨迹蒙特卡罗方法模拟了该过程,计算结果表明自身磁场可以解释电子束的发散度及其对金属丝长度的依赖关系。
禾本科植物分蘖为茎的分枝研究提供新视角

热带亚热带植物学报 , 2015, DOI: 10.11926/j.issn.1005-3395.2015.02.015
Abstract: 分蘖(或分枝)是作物产量的一个主要决定因素,受植物激素、自身生长发育和环境等因素的调控。近年报道的单子叶植物新的分蘖(或分枝)基因和调控机制深化了对植物分蘖的认知。对以禾本科植物为代表的单子叶植物的分蘖(或分枝)相关基因和调控机制进行了综述,从激素、基因、转录等几方面比较了单子叶植物分蘖和双子叶植物分枝调控机制的异同,为植物产量形成、适应环境及提高生存竞争能力的研究提供理论依据。
上面发酵高粱啤酒的工艺研究

- , 2017, DOI: 10.13982/j.mfst.1673-9078.2017.9.031
Abstract: 高粱啤酒作为一种营养丰富、口感独特的无麸质酒精饮料,具有广阔的发展前景。为研制品质优良的高粱啤酒,本研究以高粱芽为原料,分别对糖化工艺对高粱汁中总还原糖和α-氨基氮量的影响;发酵工艺对高级醇含量的影响以及发酵后不同澄清剂对高粱啤酒的澄清效果和色度的影响进行了研究。结果表明:高粱汁制备的最佳糖化方法为倾出糖化法,糖化条件为:浸酶温度35 ℃,浸酶时间20 min,糊化温度90 ℃,糊化时间30 min,糖化温度65 ℃,糖化时间1 h,糖化后高粱芽汁的总还原糖含量为83.23 g/L,α-氨基氮含量适中,为180.8 mg/L。高粱啤酒的最佳发酵条件为:高粱芽汁浓度12 °P、酵母菌接种量2.0×107个/mL、发酵温度16 ℃,发酵后啤酒中的高级醇含量为109.09 mg/L,该条件可有效降低高级醇含量。最佳的澄清剂为皂土,当添加比例为0.9%时,透光率达到90%,高粱啤酒的澄清效果最佳。在此工艺条件下,酿造出的上面发酵高粱啤酒澄清透明、色泽鲜亮、口感独特,高级醇含量适宜,是一种风味独特的新型酒精饮品。
Sorghum beer is a nutrient-rich and gluten-free alcoholic drink with unique taste, and has broad prospects for development. To develop good-quality sorghum beer, sorghum malt was used as a raw material to study the effects of the mashing process on the content of total reducing sugars and α-amino nitrogen in sorghum wort, the effects of fermentation conditions on the production of higher alcohols, and the effects of different clarifiers on the clarity and color of sorghum beer after fermentation. The results showed that the optimal mashing method was decantation, and the detailed process condition was as follows: lixiviation at 35?C for 20 min, pasting at 90?C for 30 min, and saccharification at 65?C for one hour. The content of total reducing sugar in sorghum wort produced by the above techniques was 83.23 g/L, while the content of α-amino nitrogen was moderate and the final content was 180.8 mg/L. The optimum fermentation conditions were determined as follows: sorghum wort concentration: 12 °P, the quantity of inoculated yeast: 2.0 × 107 cells/mL, fermentation temperature: 16?C. The content of higher alcohols was 109.09 mg/L in sorghum beer, and these fermentation conditions could effectively reduce the content of higher alcohols. In addition, the best clarifier was bentonite, and when the proportion of added clarifier was 0.9%, the light transmittance was 90% and the best clarification effect of sorghum beer was achieved. Under this brewing condition, the top-fermented sorghum beer obtained was clear, had a bright color, unique taste, and moderate content of higher alcohols, and was a new type of alcoholic beverage with a unique flavor.
聚n,n-二乙基丙烯酰胺溶液粘度的温度依赖性
,柳明珠
物理化学学报 , 2002,
Abstract:
介孔碳泡沫分子筛的制备及其对葡萄糖氧化酶的吸附行为
Preparation and Glucose Oxidase Adsorption Performance of Carbonaceous Mesocellular Foams
 [PDF]

, 庄凯, 尹光福
Material Sciences (MS) , 2014, DOI: 10.12677/MS.2014.42004
Abstract:
以添加氟化铵改性的介孔二氧化硅泡沫分子筛为模板,糠醇为碳源,运用硬模板法制备不同孔结构的介孔碳泡沫分子筛。采用SEM观察、TEM观察及氮气吸附等手段对介孔碳泡沫分子筛的粒径及孔结构进行了表征。结果表明,经氟离子改性的介孔泡沫分子筛具有较小的颗粒粒径及较大的窗口孔径、胞体孔径和孔容,但比表面积较小。将所制备的介孔碳泡沫分子筛和介孔二氧化硅泡沫分子筛分别用于葡萄糖氧化酶的负载,介孔碳泡沫分子筛对葡萄糖氧化酶的吸附量远远大于相应的硅模板,表明酶分子和载体表面间的静电作用对负载过程有很大影响;同时,拥有较小粒径、较大胞体孔径和孔容的介孔碳泡沫分子筛表现出更大的葡萄糖氧化酶负载量,有望成为优良的酶载体材料
By using fluorine-modified and original mesostructured cellular foam silica as templates, furfuryl alcohol as carbon precursors, carbonaceous mesocellular foams with different pore sizes were prepared, and then the grain sizes and pore structures of the samples were characterized by scanning electron microscope (SEM), Transmission Electron Microscopy (TEM) and nitrogen adsorption. It was found that fluorine-modified mesostructured cellular foams possessed the smaller particle sizes and specific surface area, but the larger windows and cell diameters and the larger pore volumes. All prepared samples were used as the carriers for immobilization of glucose oxidase. The loading amounts on carbonaceous mesocellular foams were much higher than on corresponding silicon templates, indicating that the immobilization process might be affected strongly by the electrostatic repulsion between the glucose oxidase molecules and carrier surface. Furthermore, carbonaceous mesocellular foam with smaller particle size, larger window size and pore volume showed the highest glucose oxidase loading amounts. It might be served as the prospective enzyme carrier material.
流体中颗粒物在外力作用下运动速度模型的探讨
The Velocity Model of Fluid Particulate under External Force
 [PDF]

师帅,, 宁夏, 李广科
International Journal of Mechanics Research (IJM) , 2013, DOI: 10.12677/IJM.2013.23006
Abstract:

假设颗粒为球形,流体处于层流状态,通过数学手段推导出流体中颗粒物在外力作用下任意时刻的基本速度模型,并以此为基础进一步得出颗粒物在重力、离心力及静电力作用下的特定速度模型。虽然它们是在理想条件下得出的,但却有助于学生在课堂学习中更好的理解该部分内容,并加以应用。此外它们还可以为水及大气污染控制中各相关除尘器、沉淀池的设计参数提供重要依据,有助于提高其在实际工程设计中的应用价值。

On the assumption that the particulates are spherical and the fluid is under laminar conditions, the basic ve- locity model is deduced for the fluid particulate under external force at any moment by mathematical means, and the specific velocity models are further inferred in the effects of gravity, centrifugal and static electricity. It has instructive meaning in helping students understand in class and apply the theory to practice, although it is obtained under ideal conditions. Furthermore, the kinematic velocity of fluid particulate is a major parameter in designing the related dust catcher and sedimentation basin in water and air pollution control, so the study of the velocity model of fluid particulate can redound the application value in actual engineering design.

生丝细度非接触式实时动态测量
,周望
纺织学报 , 2012,
Abstract: 为了顺应学科发展趋势和满足巢丝现场工业测量要求,针对现有生丝(纤维)细度测量仪器和检测方法存在的问题,提出一种基于线阵CCD非接触式实时动态检测生丝细度的设计方案。旨在研发一种具有高精度、准确率高、非接触性、动态检测、便于计算机处理、易于和自动控制设备连接的生丝细度的光电测量仪。本文对激光光源理论设计、光学系统的设计、CCD图像传感成像模式的选取、视频信号处理方法实验与研究,从理论设计到各个功能模块的参数设定,提高了系统测量精度。系统解决了光源照度不稳定性和生丝透明度造成的影响,避免了CCD在亮背景成像时易饱和、及生丝样品抖动引起的失真,最终通过实验验证,研究方案有一定的可行性和实用性。
Page 1 /24831
Display every page Item


Home
Copyright © 2008-2017 Open Access Library. All rights reserved.