带旋转自由度的精化非协调平面四边形等参元

对于C~1类不协调元文[1]提出了一种精比直接刚度法。本文进一步将其应用到C~0类问题,建立一种带旋转自由度的不协调平面四边形单元,其协调部分是用人Allman插值法建立的单元函数,不协调部分用了四个内部自由度。该单元能保证通过分片试验,保持了单变量有限元列式简单、性能可靠(无多余零能模式及坐标不变性)等长处,同时,还具备多变量有限元(杂交/拟协调元)高精度的优点。算例表明,本文提出的单元收敛、可靠、高精度且高效率。     

Generating self-accelerating Airy beams using a digital micromirror device

We report a new approach for generating an Airy beam by using a digital micromirror device (DMD) and a holographic technique where the DMD loads the desired hologram. Unique characteristics of an Airy beam, such as the non-diffraction and self-acceleration properties, were demonstrated to prove the successful construction of this type of waveform. Experimental results showed good agreement with theoretical calculations. This approach can also be used to generate other special beams.     

合同变换阵的初等变换求法

引入一类特定的初等变换“H”,使当二次型化为标准形的同时得到了合同变换阵 ,计算量较小     

Catalyst-assisted vapor-liquid-solid growth of single-crystal Ga2O3 nanobelts

Mass production of quasi-one-dimensional gallium oxide nanobelts is accomplished through graphite-thermal reduction of a mixture of gallium oxide powders and SnO2 nanopowders under controlled experimental conditions. Sn nanoparticles are located at or close to the tips of the nanobelts and served as the catalyst for the nanobelt growth by a vapor-liquid-solid mechanism. The morphology and microstructure of the nanobelts were characterized by scanning electron microscopy and high-resolution transmission electron microscopy. The Ga2O3 nanobelts grow along the [104] direction, the widths ranged from several tens to several hundreds of nanometers, and the lengths ranged from several tens to several hundreds of micrometers. The growth of Ga2O3 nanobelts is initiated by Sn nanoparticles via a catalyst-assisted vapor-liquid-solid process, which makes it possible to control the sizes of Ga2O3 nanobelts.     

一株H5N1亚型禽流感毒的分离鉴定与基因组序列分析

对一株于2005年从浙江省分离获得的禽流感病毒株（A／Chicken／zhejiang／24／2005）进行了鉴定、全基因组序列测定、分析和致病性研究．经血凝抑制试验和神经氨酸酶抑制试验证实，此分离病毒株为H5NI亚型．对该毒株的全基因组序列测定和分析显示，HA蛋白在HA1和HA2连接处，含有连续多碱性氨基酸模体（-RRKKR-）．进化分析结果表明，A／Chicken／zhejiang／24／2005（H5N1）7个基因来源于2004～2005年湖南地区流行株，但PB1基因来源于未知野禽毒株．动物实验结果显示，Ck／ZJ／24／05对鸡和鸭均具有高致病性，对小鼠无致病性，与HA的序列特征相符合．     

Simultaneous Determination of Major Flavonoids in Rat Plasma by a Rapid Resolution LC-ESI–MS Method After Oral Administration of the Flavonoid Fraction of Flos Lonicerae japonicae

A rapid resolution liquid chromatography-tandem mass spectrometric method was developed for the simultaneous analysis of four flavonoids in rat plasma. Key features of this method include a 6.5 min separation by a rapid resolution liquid chromatography system with a 4.6 × 50 mm, 1.8 μm particle size reverse phase column and detection by electrospray ionization tandem mass spectrometric performed in MS–MS mode for multiple reaction monitoring. The developed method was validated with respect to linearity, accuracy, precision and stability and applied for a pharmacokinetic study successfully after oral administration of the flavonoid fraction of Flos Lonicerae japonicae.     

Effect of deposition temperature on boron-doped carbon coatings deposited from a BCl3-C3H6-H2 mixture using low pressure chemical vapor deposition

A mixture of propylene, hydrogen and boron trichloride was used to fabricate boron-doped carbon coatings by using low pressure chemical vapor deposition (LPCVD) technique. Effect of deposition temperature on deposition rate, morphologies, compositions and bonding states of boron-doped carbon coatings was investigated. Below 1273 K, the deposition rate is controlled by reaction dynamics. The deposition rate increases with increasing deposition temperature. The activation energy is 208.74 kJ/mol. Above 1273 K, the deposition rate decreases due to smaller critical radius r_c and higher nuclei formation rate J with increasing temperature. Scanning electron microscopy shows that the structure changes from glass-like to nano-laminates with increasing deposition temperature. The boron concentration decreases with increasing deposition temperature, corresponding with increasing carbon concentration. The five types of bonding states are B-C, B-sub-C, BC₂O, BCO₂ and B-O. B-sub-C and BC₂O are the main bonding states. The reactions are dominant at all temperatures, in which the B-sub-C and PyC are formed.     

Simultaneous Determination of Major Flavonoids in Rat Plasma by a Rapid Resolution LC-ESI–MS Method After Oral Administration of the Flavonoid Fraction of Flos Lonicerae japonicae

A rapid resolution liquid chromatography-tandem mass spectrometric method was developed for the simultaneous analysis of four flavonoids in rat plasma. Key features of this method include a 6.5 min separation by a rapid resolution liquid chromatography system with a 4.6 × 50 mm, 1.8 μm particle size reverse phase column and detection by electrospray ionization tandem mass spectrometric performed in MS–MS mode for multiple reaction monitoring. The developed method was validated with respect to linearity, accuracy, precision and stability and applied for a pharmacokinetic study successfully after oral administration of the flavonoid fraction of Flos Lonicerae japonicae.

     

反相高效液相色谱法分析化学合成胸腺素α1

利用反相高效液相色谱(RP-HPLC)法,对化学合成的胸腺素α1进行了分析.采用PLATINUM C18柱(250 mm×4.6 mm i.d.,5 μm,10 nm),柱温室温;流动相A100%H2O(含0.1%TFA);B90%乙腈水(含0.1%TFA),18%B-A的等梯度洗脱;流速为1 mL/min;检测波长为214 nm;进样量为20 μL.用外标法定量.实验结果表明,该测定方法的检出限为4 mg/L;平均回收率为95.8%;日内精密度(用相对标准偏差RSD表示)均在10%以内,胸腺素α1在选定的浓度范围内具有良好的线性相关性.该方法简便、快速、准确,20 min内就可以完成一个样品的分析,故对胸腺素α1的定量分析具有重要的实用价值.     

多孔硅中的1.54μm光发射

本文报道了利用离子注入技术制备多孔硅中Er³⁺的1.54μm光发射发光材料的实验,并对样品的低温光致发光特性进行了实验研究。实验表明多孔硅中的Er³⁺发光与单晶硅中的Er³⁺发光(同样注入条件,退火工艺制备)相比,发光强度有成数量级的提高,同时发光峰更宽,伴线更丰富。