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单位球上bloch型空间中复合算子的本性模估计  [PDF]
曾红刚,陈仁毓
天津大学学报(自然科学与工程技术版) , 2008,
Abstract: 设bn是n维复空间cn中的单位球,φ=(φ1,…,φn)是bn到自身的一个全纯映射,令p,q>0,复合算子cφ由(cφf)(z)=f(φ(z))定义,通过找到一个性质很好的检验函数(见命题1)得到了单位球上p-bloch空间到q-bloch空间之间的有界复合算子cφ的本性模的下界估计(具体结果见定理1).
Hemispheric Asymmetries: The Comparative View  [PDF]
Sebastian Ocklenburg,Onur Güntürkün
Frontiers in Psychology , 2012, DOI: 10.3389/fpsyg.2012.00005
Abstract: Hemispheric asymmetries play an important role in almost all cognitive functions. For more than a century, they were considered to be uniquely human but now an increasing number of findings in all vertebrate classes make it likely that we inherited our asymmetries from common ancestors. Thus, studying animal models could provide unique insights into the mechanisms of lateralization. We outline three such avenues of research by providing an overview of experiments on left–right differences in the connectivity of sensory systems, the embryonic determinants of brain asymmetries, and the genetics of lateralization. All these lines of studies could provide a wealth of insights into our own asymmetries that should and will be exploited by future analyses.
关节腔内注射用氟比洛芬明胶微球  [PDF]
钟延强,任常顺,王春燕,高申,李国栋,居红卫
药学学报 , 1999,
Abstract: 目的:制备关节腔注射用氟比洛芬明胶微球。方法:按均匀设计法筛选乳化冻凝法制备氟比洛芬明胶微球(fpgms)的最佳制备工艺。结果:微球粒径范围为2.5~12.3μm,平均粒径为7.53μm,氟比洛芬含量为5.02%(w/w)。其体外释药符合higuchi方程,稳定性实验表明,fp-gms的稳定性良好,兔关节腔内注射后,与溶液剂对照组相比氟比洛芬体内平均驻留时间(mrt)显著延长(p<0.01),峰时比对照组延长2.03倍,峰浓度比对照组减小5.57倍。体内外相关性研究表明,fp-gms体外累积溶出百分率与兔体内药物吸收分数呈显著相关(p<0.01)。结论:本法制备的氟比洛芬明胶微球粒径分布集中,粒径大小符合设计要求,体内外释药结果表明氟比洛芬明胶微球具有明显的缓释作用。
Phase lags of solar hemispheric cycles  [PDF]
J. Murak?zy,A. Ludmány
Physics , 2013, DOI: 10.1111/j.1365-2966.2011.20011.x
Abstract: The North-South asymmetry of solar activity is variable in time and strength. We analyse the long-term variation of the phase lags of hemispheric cycles and check a conjectured relationship between these phase lags and the hemispheric cycle strengths. Sunspot data are used from cycles 12-23 in which the separation of northern and southern hemispheres is possible. The centers of mass of the hemispheric cycle profiles were used to study the phase relations and relative strengths of the hemispheric cycles. This approach considers a cycle as a whole and disregards the short-term fluctuations of the cycle time profile. The phase of the hemispheric cycles shows an alternating variation: the northern cycle leads in 4 cycles and follows in 4 cycles. No significant relationship is found between the phase and strength differences of the hemispheric cycles. The period of 4+4 cycles appears to be close to the Gleissberg cycle and may provide a key to its physical background. It may raise a new aspect in the solar dynamo mechanism because it needs a very long memory.
茼 蒿 品 种 比 较 试 验  [PDF]
刘乐承,张洪涛
北方园艺 , 2010, DOI: 10.11937/bfyy.201023012
Abstract:
液滴法制备高尺度比玻璃微球壳的研究  [PDF]
邱龙会,傅依备,汪小琳,魏胜,师韬
强激光与粒子束 , 1999,
Abstract: ?定量给出了液滴法制备玻璃微球壳(hgm)的直径与壁厚之间的依存关系,确定了制备大直径薄壁hgm的液滴炉温度分布、抽气速率、溶液浓度和液滴发生器操作参数等工艺条件,制备出直径为300~450μm、壁厚为0.7~1.2μm、尺度比为300~700的hgm,表面粗糙度优于10nm,球形度和同心度均优于97%,耐外压能力大于0.91mpa,耐内压能力至少大于0.43mpa。
惯性约束聚变靶用空心玻璃微球纵横比的调控  [PDF]
漆小波,高聪,张占文,李波,魏胜
化工学报 , 2012, DOI: 10.3969/j.issn.0438-1157.2012.11.016
Abstract: 为实现对惯性约束聚变(ICF)靶用空心玻璃微球(HGM)纵横比的调控,基于对干凝胶法制备HGM炉内成球过程的分析,建立了HGM纵横比的定量控制模型,实验研究了载气组分和压力对HGM直径和纵横比的影响。结果表明:通过调节载气中氩气分压可以控制熔融玻璃液泡的膨胀程度,从而定量控制最终HGM的直径和纵横比。但是,通过大幅度降低载气中的氩气分压来提高HGM半径和纵横比是不可行的。为提高载气的传热能力,确保HGM球形度、表面粗糙度和合格率满足ICF制靶的要求,必须在载气中添加一定分压的氦气。除部分极端工艺条件外,提出的HGM纵横比控制模型预测值与实验结果吻合良好。
低液固比体系高岭土微球原位合成Y沸石  [PDF]
顾建峰,崔楼伟,王新星,何观伟,王长发
化工进展 , 2012,
Abstract: 以高岭土微球为全部硅铝原料,经焙烧、碱抽提、水热处理等工艺,直接原位晶化合成了Y分子筛。扫描电镜分析表明在高岭土微球上均匀生成了晶型完整、粒度为1μm左右的Y分子筛。结合X射线测试方法详细研究了体系硅铝比、碱度、碱抽提时间、导向剂构成及添加时间对Y分子筛合成的影响。研究表明该水热反应体系的最佳配比为n(SiO2)/n(Al2O3)=10.0。反应适宜的碱度条件为n(Na2O)/n(SiO2)=0.56,n(H2O)/n(Na2O)=35,碱度过高或过低都易有P杂晶生成。碱抽提过程对合成Y分子筛十分关键,最佳的抽提时间控制在12h。导向剂构成为透明高清状,加入时间控制在碱抽提结束时最优,此时合成的Y分子筛品质最好。
Monotone versions of $δ$-normality  [PDF]
Lylah Haynes,Chris Good
Mathematics , 2007,
Abstract: We continue the study of properties related to monotone countable paracompactness, investigating various monotone versions of $\delta$-normality. We factorize monotone normality and stratifiability in terms of these weaker properties.
Hemispheric differences in the mesostriatal dopaminergic system  [PDF]
Ilana Molochnikov,Dana Cohen
Frontiers in Systems Neuroscience , 2014, DOI: 10.3389/fnsys.2014.00110
Abstract: The mesostriatal dopaminergic system, which comprises the mesolimbic and the nigrostriatal pathways, plays a major role in neural processing underlying motor and limbic functions. Multiple reports suggest that these processes are influenced by hemispheric differences in striatal dopamine (DA) levels, DA turnover and its receptor activity. Here, we review studies which measured the concentration of DA and its metabolites to examine the relationship between DA imbalance and animal behavior under different conditions. Specifically, we assess evidence in support of endogenous, inter-hemispheric DA imbalance; determine whether the known anatomy provides a suitable substrate for this imbalance; examine the relationship between DA imbalance and animal behavior; and characterize the symmetry of the observed inter-hemispheric laterality in the nigrostriatal and the mesolimbic DA systems. We conclude that many studies provide supporting evidence for the occurrence of experience-dependent endogenous DA imbalance which is controlled by a dedicated regulatory/compensatory mechanism. Additionally, it seems that the link between DA imbalance and animal behavior is better characterized in the nigrostriatal than in the mesolimbic system. Nonetheless, a variety of brain and behavioral manipulations demonstrate that the nigrostriatal system displays symmetrical laterality whereas the mesolimbic system displays asymmetrical laterality which supports hemispheric specialization in rodents. The reciprocity of the relationship between DA imbalance and animal behavior (i.e., the capacity of animal training to alter DA imbalance for prolonged time periods) remains controversial, however, if confirmed, it may provide a valuable non-invasive therapeutic means for treating abnormal DA imbalance.
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