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Search Results: 1 - 10 of 69068 matches for " 邓敏思 "
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la促进cuco催化剂上合成气转化制低碳醇的研究
士丽,储伟,
燃料化学学报 , 2012,
Abstract: ?利用超声辅助的反相共沉淀法制备了合成气选择转化制低碳醇用cuco基催化剂。研究稀土la助剂对cuco基复合氧化物催化剂结构的影响和催化性能的促进作用,借助x射线衍射(xrd)、n2吸附等温线(bet)和程序升温脱附(co-tpd)等测试技术对催化剂进行表征,并以co加氢合成低碳醇为模型反应对其催化性能进行评价。结果表明,la助剂的添加使催化剂晶粒细化,显著加大了比表面积,促进了合成醇活性位的形成,提高了催化剂表面较强吸附co物种的浓度,从而明显提高催化剂的活性与c2+醇选择性,有效调节了低碳混合醇中甲醇的含量。
地震资料在预防钻井漏失中的应用
The Uses of the Seismic Data in Dealing with the Well Leakage
 [PDF]


Mine Engineering (ME) , 2014, DOI: 10.12677/ME.2014.21003
Abstract:
在油气田勘探开发中,地震资料是解决问题的重要手段。本文对在钻井过程中参考地震资料,跟踪分析井下情况,实施积极预防井漏和随钻堵漏的技巧与措施进行了总结,为在钻井现场应用地震资料解决施工问题积累了经验,值得推广。
In the exploration and development of oil and gas, seismic data are the important means to solve the problems. In this paper, in terms of seismic data, the downhole track analysis, the uses of active well-leakage prevention and the techniques and measures of plugging with drilling are summarized, which accumulates the experience for application of seismic data to solve the drilling problems in the well site. It is worthy of using in the other oilfields.

论马海毛在针织服装中的肌理表达
Theory of Mohair Texture Expression in Knitted Garments
 [PDF]


Art Research Letters (ARL) , 2015, DOI: 10.12677/ARL.2015.43003
Abstract:
马海毛作为最贵羊毛中的一种,其性能与外观都具有较高的品质,了解并熟悉马海毛的特性是熟练运用马海毛的一个重要前提。在马海毛材质针织服装的设计中,了解马海毛的特性并发挥其优势,熟悉马海毛与其它纱线之间的整合关系是将马海毛运用在针织服装肌理表达中的核心。
Mohair is one of the most expensive wools, whose performance and appearance are of high quality. Understanding and being familiar with the characteristics of mohair are an important premise to use mohair skillfully. In the design of mohair knitting clothing, understanding the characteristics of mohair as well as exerting its advantage, and being familiar with the integration relationship between mohair and other yarns are cores to express mohair in knitting clothing texture.
显性雄性不育六倍体小黑麦选育初报
纪凤高,景扬,,程春生
遗传 , 1989,
Abstract: 利用Beagle等4个不含D染色体组的完全六倍体小黑麦为父本,给一个混合群体内的不育株分株系连续5次杂交(包括回交),从中选出了一个株系,其杂交(包括回交)一代始终分离出一半左右的不育株,从而认为MS_2(Tal)基因已经由4D染色体上易位到其他染色体组的某一条染色体上去了。新育成的显性雄性不育六倍体小黑麦雄性不育彻底且稳定,异交结实率高,无其他不良性状,可作为六倍体小黑麦杂交育种(特别是轮回选择育种)的好工具来使用。
温度对镁合金铸锭压缩变形行为的影响
曹韩学,,廖慧,永涛
重庆大学学报 , 2005, DOI: 10.11835/j.issn.1000-582X.2005.12.003
Abstract: 论述了在不同温度下对AM60B镁合金铸锭单向压缩的塑性变形试验分析.结果表明:室温下镁合金AM60B的变形能力有限,在较小的变形量下即产生裂纹;在300~400℃范围内,AM60B表现出良好的塑性,且温度越高,塑性越好;经过压缩变形后,试样硬度明显提高.
预应力碳纤维板加固钢结构预应力损失研究
朗妮,,廖羚,余兆航,姬帅
工业建筑 , 2014, DOI: 10.13204/j.gyjz201402031
Abstract: 预应力碳纤维板加固钢结构是具有明显加固效果和广阔应用前景的加固技术,碳纤维板在张拉及使用阶段的预应力损失研究是预应力加固技术的一个重要课题。在分析总结现有预应力碳纤维张拉设备及施工工艺的基础上,借鉴预应力混凝土结构预应力损失的分析方法进行分项计算,并提出各项预应力损失的计算方法。利用自主研发的一套碳纤维板张拉及锚固装置对3根钢梁进行加固试验,试验结果表明,提出的计算方法可行。建议预应力碳纤维板加固钢结构的预应力损失估算值取为张拉控制值的15%。
腹腔镜结直肠癌根治术在合并慢性阻塞性肺疾病患者中的可行性研究
陈艳,黄斌,任明扬,,
华西医学 , 2014, DOI: 10.7507/1002-0179.20140090
Abstract: 目的 探讨合并慢性阻塞性肺疾病(COPD)的患者行腹腔镜结直肠癌根治术的可行性。方法 2008年10月-2012年12月74例合并COPD患者接受腹腔镜结直肠癌根治术,回顾性分析患者临床资料,统计呼吸系统相关并发症发生率,评价手术安全性。结果 术后发生肺部感染5例,切口感染2例,吻合口瘘2例,肺不张2例,无气胸、急性呼吸窘迫综合征尿路感染、深静脉血栓及肠梗阻发生无围手术期死亡;术后拔管时间(26.72±15.07)min,下床活动时间(2.18±0.91)d,排气时间(1.85±0.79)d,排便时间(4.14±1.06)d,进流质时间(2.62±0.70)d术后住院时间(10.53±1.75)d。术后随访3个月,无死亡或复发。结论 在呼吸专科医师参与下通过充分细致的围术期处理,合并COPD的患者行腹腔镜结直肠癌根治术是可行的。
肾移植受者与普通患者泌尿系统感染的比较
,于立新,文锋,苗芸,刘如,叶桂荣
- , 2016, DOI: 10.3785/j.issn.1008-9292.2016.03.14
Abstract: 目的: 分析肾移植受者与普通患者泌尿系统感染(UTI)的不同,探究肾移植受者UTI的合理诊治方案。方法: 对2003年1月至2014年8月在南方医院确诊UTI的肾移植受者和普通患者进行回顾性分析,比较两组患者UTI特点。结果: 49例肾移植受者共发生69次UTI,401例普通UTI患者共发生443次UTI;肾移植受者和普通UTI患者均以女性居多(63.3%和58.6%),大肠埃希菌感染频率均最高(37.7%和34.1%);两组UTI患者其他病原体易感性不一致:肾移植受者肺炎克雷伯杆菌频率高于普通患者(11.6%与3.2%,P=0.001),而白色念珠菌频率低于普通患者(1.5%与11.3%,P=0.008);肾移植受者尿路刺激征更多见,更易发生抗生素耐药,感染复发率更高(38.8%与16.7%,P<0.001);肾移植受者发生UTI时外周血中性粒细胞百分率高于普通患者[(72.65±1.90)%与(68.59±0.73)%,P=0.048],淋巴细胞百分率[(17.73±1.29)%与(21.28±0.61)%,P=0.037)]和血小板计数[(187.64±10.84)×109/L与(240.76±5.26)×109/L,P<0.01]均低于普通患者。结论: 肾移植受者与普通患者UTI的特点不尽相同,早期行中段尿培养、合理使用抗生素、及时调整免疫抑制剂剂量对于肾移植受者UTI的防治具有重要意义。
切削厚度与刀具前角对松木切削力与切削温度的影响
鲍旭,郭晓磊,曹平祥,,王金鑫
- , 2018, DOI: 10.13360/j.issn.2096-1359.2018.06.019
Abstract: 为研究直角自由切削松木过程中,切削厚度和刀具前角对切削力和切削区温度的影响,选用马尾松为切削材料,在牛头刨床上进行切削试验。采用石英三向测力仪和红外热成像仪分别测量了切削力和切削区温度,并用高速相机拍摄了切削动态过程,分析切削厚度、刀具前角以及切屑形成对切削力和切削区温度的影响。结果表明:从切削力变化的总趋势来看,平行于切削方向的水平分力Fx和垂直于切削方向的垂直分力Fy均随着切削厚度的增加而增大,随着刀具前角的增大而减小; 在切削厚度为0.3 mm,刀具前角为40°和50°时,切屑为折断型切屑,其形成过程中所产生的超越裂缝可能导致切削分力Fx出现下降,这不仅可以减少刀具前刀面的磨损,也可以提高刀具的切削性能和使用寿命; 而折断型切屑形成过程中所产生的超越裂缝对切削区温度并没有明显影响。此外,25°前角时的切削力和切削温度均高于40°和50°前角时,且25°前角时的切削力增加速率高于40°和50°前角时,25°前角时切削区温度的增加速率与40°和50°前角时大致相同。因此,小前角刀具对切削力的影响程度高于对切削温度的影响程度,对切削质量和切削过程的稳定性影响较大。在保证刀具切削性能和稳定性的前提下,切削加工应选择较大前角的刀具。
This paper presented a study regarding the effects of rake angle and cutting thickness on cutting force and cutting zone temperature in the process of orthogonal cutting parallel to grain. Pine(Pinus massoniana)was used as a cutting material and was conducted on a shaper, where a quartz three-component dynamometer and an infrared thermographic technique were used to measure the cutting forces and the cutting zone temperature respectively. In addition, a high-speed camera was used to catch the wood cutting dynamic process. Through the analysis of the experimental data and the general trend of cutting force, it was found that the cutting forces(horizontal force Fx and vertical force Fy)and cutting temperature decreased as the increase of rake angle and decrease of cutting thickness. However, the cutting force decreased under the cutting condition of 0.3 mm thickness of cut with 40° and 50° rake angles due to the cleavage failure parallel to grain. This can not only reduce the wear of the tool rake face, but also improve the cutting performance and service life of the tool. In contrast, the split chip type had no obvious effect on the cutting zone temperature. In addition, the cutting forces(horizontal force Fx and vertical force Fy)and cutting temperature of 25° rake angle were higher than those by cutters with 40° and 50° rake angles. The increase rate of the cutting forces of 25° rake angle was higher than that of 40° and 50° rake angles, and the increase rate of cutting zone temperature of the 25° rake angle was approximately the same as that of 40° and 50° rake angles. Therefore, the influence of small rake angle on cutting forces was higher than that on cutting temperature, and it had great influence on the surface quality and the stability of the processing. On the premise of ensuring the cutting performance and processing stability, the tools with a large rake angle should be chosen for the cutting
住宅商品房市场细分—基于A市居民购房意向调研
Residential Real Estate Market Segmentation—Based on Residents Purchase Intention Survey of A City
 [PDF]

, 费宇
Modern Marketing (MOM) , 2016, DOI: 10.12677/MOM.2016.63006
Abstract:
为了更好地了解消费者的购房需求,细分住宅商品房市场,为房地产商制定精准的市场营销策略提供借鉴,本文将传统的统计学方法和机器学习的方法相结合定量分析了住宅商品房市场的需求状况。首先,文章结合以往研究经验选取房地产市场细分指标,通过问卷调查获取A市居民的购房意向与需求信息。然后,采用K-means聚类分析和决策树分类方法将消费者分为四类。最后,根据分类结果,运用频数分析、百分比分析、交叉列联分析方法得出了每一个类别的市场特征和需求倾向,为房地产开发商精准营销提供借鉴。同时,本文还得出了四类市场群体在住宅户型、购房关注点等方面的选择共性,为房地产开发商初期项目建设也有一定的指导意义。
In order to better understand the housing demand of consumer, divide the residential real estate market, and provide reference for precise marketing strategies for real estate developers, this paper, combining the traditional statistical methods and machine learning method, analyzes the residential housing market demand in quantitative way. First of all, this paper bases previous re-search experience to select indicators for the real estate market segmentation, through the ques-tionnaire survey to obtain A city’s information about residential purchase intention and demand. Then, through using the K-means cluster analysis and decision tree classification method, it comes to the conclusion that consumers can be divided into four groups. Finally, according to the classi-fication results, and using frequency, percentage, cross contingency analysis methods, it shows demand characteristics and tendencies of each category. All of these provide reference for real estate developers in their project preparation stage.
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