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141.
刘雄平 《大连民族学院学报》2005,7(4):36-39
老舍小说中的众多人物根据其鲜明的文化身份,大致可分为“老派人物”、“理想人物”、“新派人物”三大类。他们的身份虽不同,但悲剧性的命运却十分相似。其悲剧主要是由他们各自所负载的文化与时代、历史的不谐调造成的。三类人物分别属于“被旧文化管辖而死的悲剧”、“反抗旧文化而死的悲剧”、“受劣质文化浸染而死的悲剧”,虽不悲壮激烈,却也深沉凝重,令人警醒。 相似文献
142.
对晋矮1号×壶瓶枣的离体杂交以及杂交子房和胚珠的离体培养进行了研究.结果表明:附加1.0mg/LIBA的KM8p培养基对枣子房的离体培养较为适宜,ZT对子房的成活具有促进作用,子房的愈伤组织化可减缓子房室内胚珠的败育程度. 相似文献
143.
徐艳萍 《西安联合大学学报》2005,8(3):28-31
埃兹拉·庞德是20世纪西方诗坛最有影响、最有争议的大诗人之一.他发起了意象派运动,他的意象经典小诗<在地铁车站>广为传诵,<诗章>是其里程碑式的现代派诗歌巨著.他谙熟古今,善于旁征博引,撷取各国文化之长为己所用,东方文化使他受益匪浅.他的诗歌理论在很多方面得益于东方文化,特别是中国的古诗和日本的俳句. 相似文献
144.
介绍了企业核心竞争力的内涵和特点,阐述了领导力与竞争力的关系,从学习能力、企业文化塑造、执行力、配置资源的能力等方面论述了企业领导力的培养。 相似文献
145.
本文首先介绍CAD/CAM的产生及发展。然后谈CAD/CAM对建筑机械业的影响。本主独道见解是:CAD/CAM技术对建筑机械业影响巨大,一个全新的计算机辅助建筑工程制造CAEM概念将产生。当CAEM实现时,建楼房将象儿童搭积木房子一样轻而易举。“安得广厦万千间,使得天下寒士尽欢颜”梦想会成真。 相似文献
146.
应用本文所提出的公式可计算地层的初始应力和由开挖引起的洞周位移。预报公式所需要的计算数据是一组相邻测点之间的量测位移,这可通过隧洞的施工监控量测而得到。在推导这些预报公式时,著者先应用一系列的有限元和无限元等数值计算方法来模拟洞室的开挖,从而得到大量的“观测数据”。然后综合应用自动回归和解析方法,建立了实用的计算公式。这些公式使用简便且具有良好的精度。 相似文献
147.
Pappa A. Kyriakou S. Mikedi K. Tzamtzis N. Statheropoulos M. 《Journal of Thermal Analysis and Calorimetry》2004,78(2):415-426
The design, the abilities and a characteristic application of an in-house made interface for combining thermogravimetry (TG)
with mass spectrometry (MS) are presented. The TG-MS interface consists mainly of three co-axial tubes. The position of the
intermediate tube was determined after calculation of the temperature profile at the TG furnace exit tube. The inner tube
position was determined taking into consideration its protection against condensation of heavy molecules and the time delay
for the transfer of the evolved gases. This interface allows either continuous sampling and transferring of the evolved gases
from the TG to the MS or repetitive introduction of short sampling pulses of TG evolved gases to MS. The interface is capable
of coupling various commercial instruments. In the present work two configurations of this interface are demonstrated. Finally
an example of application of this interface on forest fuel pyrolysis is presented.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
148.
The ability to recover and purify natural and recombinant proteins, and the costs of doing so remain a major task in introducing
the potential products of biotechnology. The bases for separation range from specific binding onto tailored reagents to solubility
and partitioning behavior governed by a mixed bag of size, charge, and hydrophobicity. In most cases, a combination of methods
is used in sequence, and improvements in the selectivity at an early stage can enhance the effectiveness of subsequent (and
usually more costly) steps. Genetic engineering provides a means of improving the selectivity within the context of existing
separation methods.
By this strategy, improvements in selectivity are sought by bestowing a distinctive property on the protein of interest. The
primary sequence of amino acids is altered, such that the protein can be selectively removed from other components of the
multicomponent mixture in which such products are commonly found. In this article, the range of these “distinctive properties”
and their pairing with various separation methods will be reviewed. Specific examples from our work, in which a distinctive
charge is provided via a polypeptide “purification” fusion tail, will be discussed. Separation methods we have used with these
fusion proteins are precipitation, two-phase aqueous extraction, reversed micellar extraction, and ion exchange using both
resins and membranes. 相似文献
149.
Fibers and 3D mesh scaffolds from biodegradable starch-based blends: production and characterization
The aim of this work is the production of fibers from biodegradable polymers to obtain 3D scaffolds for tissue engineering of hard tissues. The scaffolds required for this highly demanding application need to have, as well as the biological and mechanical characteristics, a high degree of porosity with suitable dimensions for cell seeding and proliferation. Furthermore, the open cell porosity should have adequate interconnectivity for a continuous flow of nutrients and outflow of cell metabolic residues as well as to allow cell growth into confluent layers. Blends of corn starch, a natural biodegradable polymer, with other synthetic polymers (poly(ethylene vinyl alcohol), poly(epsilon-caprolactone), poly(lactic acid)) were selected for this work because of their good balance of properties, namely biocompatibility, processability and mechanical properties. Melt spinning was used to produce fibers from all the blends and 3D meshes from one of the starch-poly(lactic acid) blends. The experimental characterization included the evaluation of the tensile mechanical properties and thermal properties of the fibers and the compression stiffness, porosity and degradation behavior of the 3D meshes. Light microscopy picture of 3D meshes. 相似文献
150.
Shetty Kalidas Korus roger A. Crawford Dom L. 《Applied biochemistry and biotechnology》1989,(1):825-843
Glycine max was used as a model plant cell suspension culture to establish relationships among growth kinetics, phenolics production,
elicitor action, and peroxidase activity. Timing of elictor addition through monitoring of peroxidase provided an excellent
means of optimizing yields of phenolics and reduced the time span during which phenolics were formed, negating the need for
a secondary production medium. We have also determined that calcium and other cellular effectors like polyamines and organic
osmolytes, when used in conjunction with elicitors, enhance phenolics production. Calcium directly enhanced elicitation, whereas
polyamines and other osmolytes such as glycerol and proline extended cell viability. The study also demonstrated potential
for enhancing secondary metabolite production by a combination of elicitation, cell viability stabilizers, and by addition
of nutrients at the time of elicitation. 相似文献