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Search Results: 1 - 10 of 52589 matches for " 肖燕 "
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基于ArcGIS Model Builder的地形指数提取方法及实践研究
The Study on Terrain Index Extraction Method and Practice Based on ArcGIS Model Builder
 [PDF]

, 解鹏
Geomatics Science and Technology (GST) , 2013, DOI: 10.12677/GST.2013.13003
Abstract:
流域地形指数水文模型TOPMODEL已被应用于陆面模式(Land surface Models, LSMs)以改进陆面模式对水文过程的模拟。地形指数(ln(α/tanβ))是TOPMODEL的核心,是进行水文分析的重要指标。因此,高效的提取地形指数信息非常重要。本文将淮河流域作为案例区,以地形指数单流向算法为理论基础,利用ArcGIS9的Model Builder建模工具,建立地形指数提取模型。在模型设计过程中充分考虑到汇流面积、坡度等参数的有效性,使模型具有较高的通用性。使用者启动模型加载数据即可简单又快速地获得地形指数分布数据。
River terrain index TOPMODEL hydrological model has been applied to Land surface model (Land surface Models, LSMs), to improve Land surface of hydrological process simulation model. The core of TOPMODEL is terrain index (ln(α/tanβ)). And it is an important index on the hydrologic analysis. Therefore, effective extracting terrain index information is very important. In this paper, the huaihe river basin as a case area, the terrain index extraction process model is build, using the ArcGIS9 Model Builder tools. This model is based on a single flow algorithm for calculating process. Model has higher versatility, because of fully considering the effectiveness of the parameters such as the slope and the flow accumulation in the model design process. Using this model can be very simple and quick to get terrain exponential distribution data of terrain index.
CMs/nHA/PLGA复合支架的制备及体外释放性能的研究
Preparation and Release Performance in Vitro of Chitosan Microspheres/nHA/PLGA Compound Scaffolds
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Material Sciences (MS) , 2016, DOI: 10.12677/MS.2016.64033
Abstract:
本研究以胰蛋白酶(Try)为模型蛋白,将壳聚糖缓释微球与可降解多孔支架复合,构建可次第释放不同生长因子的骨组织工程支架。首先,制备载胰蛋白酶的壳聚糖微球(Try-CMs),然后将微球与纳米羟基磷灰石/羟基乙酸(nHA/PLGA)按照一定的比例混合,通过粒子沥虑–冷冻干燥复合工艺制备Try-CMs/ nHA/PLGA复合支架。结果表明,制备的Try-CMs呈规则球形,粒径分布在4~10 μm之间,胰蛋白酶包封率为61.33%,载药量为25.69%。制备的Try-CMs/nHA/PLGA复合支架孔径为100~200 μm,孔隙率为53.24%,抗压强度为7.31 MPa,8周降解率为19.92%。48 h,Try-nHA/PLGA、Try-CMs、Try-CMs/nHA/ PLGA复合支架累计释放率分别57.31%、69.32%和26.03%;14天时,Try-nHA/PLGA、Try-CMs和Try-CMs/nHA/PLGA复合支架的累计释放率分别为77.89%、85.73%和54.53%。Try-CMs/nHA/PLGA复合支架对蛋白药物具有良好的缓释作用,有望作为具有蛋白类药物缓释作用的组织工程支架。
In order to construct a bone regeneration scaffold that different growth factors controlled release at proper stage, Trypsin (Try) was selected as the model protein. The composite of sustained-re- lease microspheres and biodegradable porous scaffolds was prepared in this study. Firstly, Tryp-sin-chitosan microspheres (CMs) were prepared. Then, Trypsin-CMs were compounded to the nano hydroxyapatite/poly lactic-co-glycolic acid (nHA/PLGA) to build a scaffold that could release growth factors sequentially. The results showed that the Try-CMs were spherical shape with diameters of 4 - 10 μm. The encapsulation efficiency of the Trypsin in CMs was 61.33%, and the loading capacity was 25.699%. The prepared Try-CMs/nHA/PLGA scaffold possessed 100 - 200 μm pore diameter, 53.24% porosity, 7.31 MPa compressive strength, and 19.92% degradation at 8 weeks. The cumulative releases of Trypsin from Try-nHA/PLGA, Try-CMs and Try-CMs/nHA/PLGA scaffolds were respectively about 57.31%, 69.32% and 26.03% at 48 hours, 77.89%, 85.73% and 54.53% at 14 days. The results demonstrated that Try-CMs/nHA/PLGA scaffolds had excellent drug sustained-release performance, which would be used as tissue engineering scaffolds with protein controlled delivery.
BMP-2-PLLA缓释微球的制备及其对BMP-2活性的维持
Preparation of BMP-2-PLLA Microspheres and Its Maintenance for Bioactivity of BMP-2
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Material Sciences (MS) , 2016, DOI: 10.12677/MS.2016.64035
Abstract:
本研究探索载骨形态发生蛋白-2 (BMP-2)的左旋聚乳酸(PLLA)载药微球的制备条件,并检测BMP-2- PLLA微球中BMP-2的释放规律和生物活性。采用乳化法制备载牛血清白蛋白(BSA)的聚乳酸(PLLA)载药微球,考察PLLA分子量、PLLA浓度、PEG分子量对PLLA载药微球粒径、包封率和载药量的影响,选择优化条件制备载BMP-2的PLLA微球,通过细胞合成ALP检测BMP-2的活性。实验制备的BMP-2-PLLA微球表面光滑,粒径为4.815 μm,载药量为2.28 × 10?3%,包封率为70.88%,二氯甲烷残留量为0.0041%。BMP-2-PLLA微球有效实现了BMP-2长期稳定缓慢释。乳化过程未对BMP-2活性产生显著影响,且BMP-2-PLLA微球中释放的BMP-2对细胞合成ALP的诱导作用较BMP-2溶液更加显著。实验制备的PLLA微球可用于负载生长因子实现缓释,并能较好地维持其生物学活性。
The preparation conditions of poly-l-lactide (PLLA) microspheres, release characteristics and bi-oactivity of Bone Morphogenetic Protein-2 (BMP-2) were studied. Bovine serum albumin (BSA)- loaded PLLA microspheres were prepared with a double emulsion method. The effects of the mo-lecular weight and concentration of PLLA, the molecular weight of PEG on the particle size, loading capacity and entrapment efficiency were studied. Then, the optimal conditions were selected to prepare BMP-2-loaded PLLA microspheres, and the bioactivity of BMP-2 was investigated by pro-duction of cell Alkaline Phosphatase (ALP). The results showed that the BMP-2-PLLA microspheres were spherical shape with diameters of 4.815 μm. The encapsulation efficiency of the BMP-2 in PLLA microspheres was 70.88%, and the loading capacity was 2.28 × 10?3%. The residual amount of methylene chloride in BMP-2-PLLA microsphere was 0.0041%. BMP-2-loaded PLLA microspheres had excellent drug sustained-release performance, which would control release BMP-2. BMP-2 biological activity indicated that the biological activity was not effected after emulsion process. The bioactivity of growth factors released from PLLA microspheres was more durable and effective. PLLA microspheres prepared can be used to load growth factors to control their release and maintain their biological activity.
井盐企业辊工人力资源现状调查分析——以自贡市盐业为例
A Survey and Analysis on the Current Status of Well Salt Enterprise Gungong Human Resources—Take the Well Salt of Zigong City as an Illustration
 [PDF]

兴政,
Modern Management (MM) , 2011, DOI: 10.12677/mm.2011.12014
Abstract: 四川省自贡市素有千年盐都之称,其井盐开采具有一千多年的历史。天车是古代采盐的重要工具,也是自贡市盐业的一个象征、城市的名片。为了保护好这一物质文化遗产,我们通过实地调查与走访,得到了自贡市现有“天车”18座,但都缺少良好的维护,其中3座损毁严重,需要及时维护;维护“天车”的“辊工”仅有10人,且年龄偏大,对天车维护困难。因产盐技术的进步,天车的作用逐渐减弱,天车的维护者辊工也逐渐减少,辊工技术面临失传。如果不加以继承与保护,不重视对辊工人力资源的开发与培养,具有象征意义的天车文化将逐渐从人们的视线中消失,那将是盐业历史文化的重大损失。
City of Zigong in Sichuan province is always known as “millennium salt city”, and the well salt mining has more than one thousand years of the history. The overhead traveling crane is not only an important tool of ancient salt mining, but also a symbol of salt industry and a card of Zigong city. In order to protect the material cultural heritage, we took through on-the-spot investigation and visit, then found that there are 18 overhead traveling crane in Zigong, but they are lack of good maintenance in which three seats were badly damaged which need to be maintained timely; there are only ten rollers worker to maintain the overhead traveling crane who are too old to protect them. Because of the technological progress of salt, the affections of the overhead traveling cranes weakened and the roller work reduced gradually then the technique of roller have to face to the extinction. If we do not inherit and conserve the technique and ignore the attentions to develop and train hu-man resources of the roller workers, the overhead traveling crane culture which has the symbolic meaning will gradually disappear in front of the sight line of the people, which will be a heavy loss upon the history and cul-ture of the salt industry.
追寻著作权保护与权利限制的平衡——图书馆界对《著作权法》修改草案的建议与期盼

中国图书馆学报 , 2013,
Abstract: 我国《著作权法》第三次修订工作于2011年7月启动,2012年3月国家版权局发布《著作权法》修改草案第一稿,面向社会征求意见。全国图书馆界积极行动,结合实际,认真研讨,发现其中的不足有:舍弃了多个公益非营利网络传播适用的权利限制条款;信息网络传播权限制条款仍由国务院法规制定,没有由《著作权法》统一整合;没有采纳图书馆界提出的为非营利公益图书馆利用网络收集、保存、传播受著作权保护作品设置豁免条款的建议。图书馆界提出了一系列改进建议,并以书面形式上报文化部和国家版权局。2012年7月,修改草案第二稿公布,部分回应了图书馆界提出的设置合理使用兜底条款的建议,但未从根本上解决权利保护与权利限制失衡的问题,而且搁置了当代《著作权法》修订无法回避的信息网络传播权保护与限制条款的系统整合问题。图书馆界希望《著作权法》的修订落实独立性、平衡性和国际性三项基本原则,以保障著作权人利益与公众利益的平衡。参考文献4。
权威与图书馆学向常规科学的转化——读《论图书馆学研究权威》的联想

中国图书馆学报 , 1992,
Abstract:
走出象牙塔,综览科学新潮

中国图书馆学报 , 1993,
Abstract:
关于强化图书馆研究开发功能的思考

中国图书馆学报 , 2000,
Abstract: 强化图书馆研究开发功能,首先要转变观念,提高对图书馆研究开发活动重要性的认识,第二,要将研究开发活动作为常规工作,纳入图书馆工作各个环节,第三,要加强对信息技术应用的开发研究,第四,要加强对图书馆用户的研究。分析了研究开发与服务活动的关系,论述了强化研究开发功能的依据。参考文献6。
违约归责原则比较研究

浙江大学学报(人文社会科学版) , 2004,
Abstract: ?违约归责原则有严格责任与过错责任之分.大陆法系与英美法系在各自的发展历史中形成了不同的归责体系,分别有其优点与不足.由于共同的经济基础以及历史的作用,19世纪以来,两大归责原则互相兼收并蓄,呈现不断融合的趋势.回顾我国20世纪80年代以来的合同立法,有一个从崇尚绝对过错责任到强调绝对严格责任的过程.但是单一的归责制度存在不可克服的缺陷,归责原则二元化符合法律追求公平的价值目标.它在比较妥善地维护合同当事人合法权利的同时,还降低了法律的运行成本并完善了合同法的体系,体现了现代民法从形式公平向实质公平的发展趋势.
《著作权法》第三次修订与国际著作权立法进展评析

图书馆杂志 , 2014,
Abstract: ?我国《著作权法》第三次修订自2011年7月启动,2012年12月国家版权局向国务院法制办提交著作权法修改草案(第三稿)。自2005年起,wipo著作权与相关权常设委员会(sccr)将著作权限制和例外列入议事日程,致力于商讨并缔结与保障残疾人、图书馆和档案馆、教育科研机构等获取受著作权保护作品相关的限制与例外国际条约。本文介绍我国著作权法第三次修订现状,分析存在的问题,梳理评介世界知识产权组织(wipo)主导的国际著作权限制与例外立法实践和最新进展,以期为我国著作权法修订提供借鉴。
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