Effects of reinforcement filler and temperature on the stability of beta-crystal in glass bead filled polypropylene

The effects of crystallization temperature (T,), glass bead content and its size on the, formation of beta-crystal and structural stability of originally formed beta-crystal in glass bead filled polypropylene (PP) were examined. The differential scanning calorimetry (DSC) measurements indicated that the amount of beta-phase in PP crystals was a function of the crystallization temperature and glass bead content. For a constant crystallization temperature, it was observed that the amount of beta-crystal initially increased with increase in glass bead content up to 30 wt.%, and then decreased slightly with further increase in the filler content. From the DSC data, a disorder parameter (S) was derived to define the structural stability of originally formed beta-crystals. The structural stability of originally formed beta-crystals was enhanced with increase in either the crystallization temperature or the glass bead content. Also, the influence of glass bead size (4-66 mu m) on the formation and stability of beta-crystals in PP/glass bead blends was studied. Large glass bead particles suppressed the formation and decreased the stability of beta-crystals.

Organic integrated pixels fabricated by a full evaporation method

An organic integrated pixel consisting of an organic light-emitting diode driven by an organic thin-film field-effect transistor (OTFT) was fabricated by a full evaporation method oil a transparent glass substrate. The OTFT was designed as a top-gate Structure, and the insulator is composed of a double-layer polymer of Nylon 6 and Teflon to lower the operation voltage and the gate-leakage current, and improve the device stability. The field-effect mobility of the OTFT is more than 0.5 cm(2) V-1 s(-1), and the on/off ratio is larger than 10(3). The brightness of the pixel reached as large as 300 cd m(-2) at a driving current of 50 mu A.

Branched crystal morphology of linear polyethylene crystallized in a two-dimensional diffusion-controlled growth field

The branched crystal morphology of linear polyethylene formed at various temperatures from thin films has been studied by atomic-force microscopy (AFM), transmission electron microscopy (TEM), electron diffraction (ED) pattern and polymer decoration technique. Two types of branched patterns, i.e. dendrite and seaweed patterns, have been visualized. The fractal dimension d(f) = 1.65 of both dendrite and some of seaweed patterns was obtained by using the box-counting method, although most of the seaweed patterns are compact. Selected-area ED patterns indicate that the fold stems tilt about 34.5degrees around the b-axis and polymer decoration patterns show that the chain folding direction and regularity in two (200). regions are quite different from each other. Because of chain tilting, branched crystals show three striking features: 1) the lamella-like branches show two (200) regions with different thickness; 2) the crystals usually bend towards the thin region; 3) the thick region grows faster by developing branches, thus branches usually occur outside the thick region. The branched patterns show a characteristic width w, which gives a linear relationship with the crystallization temperature on a semilogarithmic plot.

Effect on the property of the photoinduced carrier transport of CdS as sensitizer for TiO2 nanoparticulate thin films

The TiO2 nanoparticle thin films have been sensitized in situ with CdS nanoparticles. The SPS measurement showed that large surface state density was present on the TiO2 nanoparticles and the surface state can be efficiently decreased by sensitization as well as selecting suitable heat treatment, Both the photocurrent response and the charge recombination kinetics in TiO2 thin films were strongly influenced by trapping/detrapping of surface states. The slow photocurrent response of TiO2 nanoparticulate thin films upon the illumination was attributed to the trap saturation effects, The semiconductor sensitization made the slow photoresponse disappeared and the steady-state photocurrent value increased drastically, which suggested that the sensitization of TiO2 thin films with CdS could get a better charge separation and provide a simple alternative to minimize the effect of surface state on the photocurrent response.

一种制备过氧化物酶的新方法

以meso 四 (α ,α ,α ,α Ο 苯乙酰苯 )卟啉为抗原 ,通过动物免疫、细胞融合等技术筛选细胞株 3E4.该细胞株产生的抗体具有结合铁卟啉的能力 ,且表现出过氧化物酶的活力 .该抗体对抗原和铁卟啉的亲和常数为 3.6 5×10 -9和 8.2 0× 10 -8.抗体 铁卟啉复合物催化反应时 ,得到比活力为 46 .875U/mg ,为天然HRP的 18.99% .

The application of matrix-assisted laser desorption jonization mass spectrometry in enzymes of Agkistrodon blomhoffii Ussurensis venom analysis

The matrix-assisted laser desorption ionization mass spectrometry (MALDI-TOF-MS) spectra of four enzymes (PLA, AEase, Fibrolase, L-a.a. oxidase) in Agkistrodon blomhoffii Ussurensis venom, were given and interpreted. The experiment data showed that MALDI-TOF-MS can be used directly in enzyme analysis with high sensitivity and rapidity. In addition, the results were better than those from sodium dodecyl sulfate-polyacrylamide.

长白山白眉蝮蛇蛇毒酶的基质辅助激光解吸质谱分析

用基质辅助激光解吸飞行时间质谱(MALDI-TOF-MS)法对长白山眉蝮蛇蛇毒所含4种主要酶:磷脂酶A_2、精氨酸酯酶、纤溶酶及L-氨基酸氧化酶进行了纯度鉴定和分子量测定,结果表明WALDI-TO-FMS具有灵敏度高、分辨能力强、分析时间短及样品用量少等优点.用MALDI-TOFMS法分析蛇毒酶的纯度和分子量简捷、快速且重现性好,是SDS聚丙烯酰胺凝胶电泳所无法比拟的.

Ring-opening polymerization of epsilon-caprolactone by lanthanocene catalysis

Ring-opening polymerization of epsilon-caprolactone (CL) catalyzed by lanthanocenes, O(C2H4C5H3CH3)(2)YCl (Cat-YCl) and Me2Si[(CH3)(3)SiC5R3](2)NdCl (Cat-NdCl) has been carried out for the first time. It has been found that both yttrocene and neodymocene are very efficient to catalyze the polymerization of CL, giving high molecular weight poly(epsilon-caprolactone) (PCL). The effects of [cat]/[epsilon-CL] molar ratio, polymerization temperature and time, as well as solvents were investigated and polymerization temperature is found to be the most important factor affecting the polymerization. The bulk polymerization gives higher molecular weight PCL and higher conversion than that in solution polymerization. NaBPh4 was found to promote the polymerization of epsilon-caprolactone, and thus to increase both the polymerization conversion and MW of poly(epsilon-caprolactone).

A preliminary study on chemistry of phenoxynaphthacenequinones

A preliminary study on the chemistry of 6-phenoxy-5,12-naphthacenesuinone derivatives was reported, It was found that the main product was 6-(N,N-dimethylamino)-5,12-naphthacenequinone when a reaction of 6-chloro-5,12-naphthacenequinone with 4-hydroxyazobenzenes in DMF was carried out under certain reaction conditions. When the reaction of 6-[4-(4-hydroxyphenyl)isopropyl)phenoxy]-5, 12-naphthacenequinone and epichlorohydrin was carried out in an acetone/DMF(V/V=2/1) mixed solvent and in the presence of K2CO3 and KI, a new phenoxynaphthacenequinone derivative,6,6'-[1-methylethylidenebis(4,1-phenyleneoxy)]bis(5,12-naphthacenequinone), was obtained.

Structure-property relationship of phenoxynaphthacenequinones and their relatives

Like 6-phenoxy-5,12-naphthacenequinone (1), 6-[4-(2-( 8-hydroxyphenyl) isopropyl)phenoxy]-5, 12-naphthacenequinone (2) and 6-naphthyloxynaphthacenequinone (6) showed normal photochromism, The relative initial rates of trans to ana photoconversion were in the order: 1, 100; 2, 37; 6, 21, 6-[4-(Phenylazo)phenoxyl-5,12-naphthacenequinone (3), 6-[4-(p-ethoxyphenylazo) phenoxy]-5,12-naphthacenequinone (4), 6-[4-(p-nitrophenylazo)phenoxy]-5,12-naph cenequinone (5) had only slight W-induced photochromism for the phenoxynaphthacenequinone photochrome. 6-(2-Nitrosonaphthyloxy)-5,12-naphthacenequinone (7) exhibited no photochromism and underwent irreversible photoreaction.

Comparative study of Nickel-based perovskite-like mixed oxide catalysts for direct decomposition of NO

The mixed oxides LaNiO3, La0.1Sr0.9NiO3, La2NiO4 and LaSrNiO4 were prepared and used as catalysts for the direct decomposition of NO. The catalysts were characterized by means of XRD, XPS, O-2-TPD, NO-TPD and chemical analysis. By comparing the physico-chemical properties and catalytic activity for NO decomposition, a conclusion could be drawn as follows. The direct decomposition of NO over perovskite and related mixed oxide catalysts follows a redox mechanism. The lower valent metal ions Ni2+ and disordered oxygen vacancies seem to be the active sites in the redox process. The oxygen vacancy plays an important role favorable for the adsorption and activation of NO molecules on one hand and on the other hand for increasing the mobility of lattice oxygen which is beneficial to the reproduction of active sites. The presence of oxygen vacancies is one of the indispensable factors to give the mixed oxides a steady activity for NO decomposition.

杂多化合物—聚吡咯膜修饰电极的制备及电化学研究

报道四元杂多化合物Ｋ１０Ｈ３［Ｎｄ（ＳｉＭｏ７Ｗ４Ｏ３９）２］·ｘＨ２Ｏ（简写为Ｎｄ（ＳｉＭｏ７Ｗ４）２１３－）聚吡咯（ＰＰｙ）膜修饰电极的制备及其电化学性能．该电极保持了四元杂多化合物的电化学活性和电催化性能，并具有很好的稳定性，在酸性水溶液中对ＮＯ－２具有明显的催化作用．

表面修饰对贮氢电极电化学性能的影响

表面修饰对贮氢电极电化学性能的影响蔡称心（南京大学化学系南京２１００９３）王宝忱（中国科学院长春应用化学研究所）关键词：贮氢电极，Ｎｉ／ＭＨ电池，表面修饰Ｎｉ／ＭＨ（ＭｅｔａｌＨｙｄｒｉｄｅ）二次电池由于在放电容量、干净度、重金属污染、耐过充过放电能...

大鼠精索静脉曲张对睾丸氧自由基和LPO浓度的影响

应用成年Ｗｉｓｔａｒ大鼠制作精索静脉曲张动物模型，术后３月，处死动物取出睾丸。以电子自旋共振（ＥＳＲ）法测试睾丸组织的氧自由基相对自旋浓度，ＴＢＡ法和化学发光法分别检测过氧化脂质（ＬＰＯ）含量、超氧化物歧化酶（ＳＯＤ）水平。实验结果表明，精索静脉曲张组（ＶＧ）左、右睾丸氧自由基自旋浓度明显高于假手术对照组（ＣＧ）（Ｐ＜Ｏ．０５）；ＶＧ双睾ＬＰＯ含量显著高于ＣＧ（Ｐ＜０．０１）；睾丸氧自由基相对自旋浓度和ＬＰＯ含量呈明显正相关（ｒ＝０．５４，Ｐ＜０．０５）；．ＶＧ双睾ＳＯＤ水平均显著低于ＣＧ（Ｐ＜０．０１）。上述结果提示：精索静脉曲张大鼠睾丸组织中含有大量的氧自由基和ＬＰＯ，损伤睾丸细胞及其各级生物膜，会导致睾丸生精功能紊乱造成不育，而睾丸氧自由基清除障碍可能是氧自由基浓度增高继之ＬＰＯ含量增多的重要机制之一。