Takagi-Sugeno模糊控制系统稳定性的充要条件的逼近

分析了Takagi-Sugeno(T-S)模糊控制稳定性,其中Lyapunov函数包括公共二次型Lyapunov函数、分段二次型Lyapunov函数、模糊Lyapunov函数、非二次型Lyapunov函数、齐次多项式型Lyapunov函数,控制律包括并行分布补偿控制律、非并行分布补偿控制律和齐次多项式型参数化控制律。基此,通过采用Polya定理、齐次多项式技术等,给出T-S模糊控制的稳定性的充要条件的逼近方法。     

Brzezinski交叉积上的一类广义双代数

设H是一个双代数,B是带有H弱作用的代数,σ：H（？）H→B和τ：H（？）H→B都是k-双线性映射.首先我们给出了B_χ~（#_σ~τ）H成为双代数的充分必要条件,此双代数带有扭曲交叉积B#_σ~τH和冲余积B×H,其中B是H上的余模余代数.此双代数是由Radford首次在文献[8]中提出,后来Doi and Takeuchi又在文献[4]和[9]中进一步推广而得到的.然后我们对此双代数进行刻画并研究其基本性质.最后我们给出了此双代数成为Hopf代数的充分条件.     

分数次积分在加权Hardy空间上的有界性

本文利用加权Hardy空间中的原子分解与分子分解,证明了具有齐型核的分数次积分算子在加权Hardy空间中的有界性.     

A comparative study of magnetic properties between whole cells and isolated magnetosomes of <Emphasis Type="Italic">Magnetospirillum magneticum</Emphasis> AMB-1

The magnetic properties of magnetosome magnetite are of interdisciplinary interest because magnetosomes are potential carriers of natural remanent magnetization and paleoenvironment, as well as novel nano-biomaterials in biotechnological and biomedical applications. We carried out magnetic and electron transmission microscopy analyses of fresh Magnetospirillum magneticum AMB-1 whole cells and isolated magnetosomes. Results revealed that AMB-1 synthesized single-domain magnetite magneto-somes, which are arra...     

High-resolution carbon isotope record for the Paleocene-Eocene thermal maximum from the Nanyang Basin,Central China

The Paleocene-Eocene thermal maximum (PETM) was a transient episode of global warming, associated with massive atmospheric greenhouse gas input that occurred at the Paleocene/Eocene boundary. Biostratigraphic and isotope stratigraphic studies indicate that the PETM event is well documented in the marl deposits of the Yuhuangding section in the Nanyang Basin, Central China, with a carbon isotope negative excursion of ~6.1‰ within 19-m-thick marl deposits. This is the highest resolution record of the PETM so far found in the world. The PETM event was triggered within 2-cm-thick marl sediments, with a decrease of δ¹³C (stable carbon isotope ratio) from –3.2‰ to –5.2‰, suggesting a massive methane hydrate release for a transient period that was possibly caused by a catastrophic event. A comparison between marine and terrestrial records indicates a “Three-Phase Model” for the PETM event. Initially there is a rapid negative excursion in the δ¹³C record, followed by a slowly decreasing trend, and then a gradual positive recovery, corresponding respectively to a rapid dissociation of oceanic methane hydrate, followed by a slow release of methane and then the consumption of the released methane.     

两电平三相逆变器效率对比分析

碳素生产中排出的沥青烟气严重污染环境,治理技术难度大,成为企业急需解决的难题。采用静电除尘器与热管换热器结合的方式,对某企业焙烧窑烟气净化进行了应用研究。实践结果表明单纯用静电除尘器易使沥青回收斗出现凝固堵塞,改用热管换热器与静电除尘器相结合治理,净化后烟气中的烟尘浓度、苯并（a）芘含量和沥青烟浓度,均达到了国家排放标准的要求。收集的沥青,可回用于生产系统。     

甘蔗渣基木陶瓷的结构及性能试验

应用不同质量比的甘蔗渣和环氧树脂进行复合、热压,经真空烧结后,制得甘蔗渣基木陶瓷.利用TG-DSC对甘蔗渣基木陶瓷的热分解行为进行初步分析,利用XRD,SEM表征了所制备的木陶瓷的相组成和微观结构,研究了甘蔗渣用量对开口气孔率及摩擦性能的影响.结果表明:甘蔗渣基木陶瓷具有生物管状的多孔结构;随着甘蔗渣用量的降低,木陶瓷的石墨化程度略有提高;木陶瓷的开口气孔率随甘蔗渣用量减少而减小;摩擦系数随转速的增加而增大,随载荷的增大而减小.当甘蔗渣/环氧树脂质量比为1∶1时,木陶瓷的开口气孔率为35.12%,摩擦性能最好.     

低压铸造充型过程的数值模拟技术

论述了低压铸造充型模拟的数学模型,由于低压铸造充填速度较慢、充型平稳,因此充型计算采用层流模型.采用SOLA-VOF算法对模型进行求解, 其中SOLA 法用于求解流体的速度场和压力场, VOF法用于处理自由表面.采用UG软件进行铸件三维造型,采用ProCAST软件进行网格划分,对叶轮的充型过程进行了模拟,并通过对叶轮的浇注试验,验证了低压铸造充型的数学模型及算法在保证模拟精度、提高计算效率上的有效性.     

顺丁烯二酸二异辛酯合成新方法

在以顺丁烯二酸和异辛醇为原料,用DMAP/DCC催化合成顺丁烯二酸二异辛酯的实验中,考察了对甲苯磺酸、浓硫酸和N,N-二环己基碳酰亚胺(DCC)、4-二甲氨基吡啶(DMAP)等几种催化剂的催化性能.结果表明,在室温条件下DCC/DMAP的催化活性高,是一种比较好的酯化反应催化剂.同时考察了反应时间、醇酸比、催化剂用量、反应温度对合成顺丁烯二酸二异辛酯收率的影响.实验结果表明,当反应时间为4h,异辛醇与顺丁烯二酸的物质的量之比为2.2:1(mol/mol),反应温度为20℃时,顺丁烯二酸二异辛酯的收率可达到91.3%.     

红树林内生真菌Paecilomyces sp．（treel—7）蒽醌类代谢产物研究

红树林内生真菌Paecilomyces sp．（treel-7）采自红树植物秋茄树皮,在实验室150L规模下静置培养．反复进行硅胶,Sephadex LH-20柱层析．通过1D,2DNMR和EI—MS等手段鉴定5个蒽醌类化合物和2个甾体类代谢产物的结构．通过MTT法测试5个蒽醌类化合物有抑制鼻咽癌细胞（KB,KBv）的活性,结果显示葸醌类化合物1-5对鼻咽癌细胞有不同程度的抑制活性．