聚丙烯性能试验方法对比研究

选择均聚聚丙烯（PP—H）、抗冲共聚聚丙烯（PP—B）、无规共聚聚丙烯（PP—R）共7个牌号的聚丙烯（PP）产品为研究对象,对比研究了国际标准化组织（简称ISO）制定的标准和美国材料试验协会（简称ASTM）制定的标准对三类PP性能测试的影响。ISO和ASTM2种标准测得的PP产品的拉伸性能、弯曲性能、缺口冲击强度和负荷变形温度存在一定的差异。但2种标准的测试结果具有一定的规律性,这些规律可为今后修订聚丙烯行业和企业标准提供参考。     

Interval-valued fuzzy backward reasoning

The importance and efficiency of backward reasoning in nonfuzzy reasoning has been stressed for a long time, especially in the case of expert systems and decision-support systems. The extension of this reasoning method to fuzzy theory, however, has never been considered. In this paper, the authors propose a definition of fuzzy backward reasoning based on the generalized modus ponens and show the necessity of considering interval-valued fuzzy backward reasoning. Then, the authors propose solving methods for fuzzy backward reasoning in the case of a rule with one or several conditions as well as in the case of several rules     

Evaluation of thermal properties of UO2 and PuO2 by equilibrium molecular dynamics simulations from 300 to 2000 K

The thermal properties of UO₂ and PuO₂ have been investigated by the equilibrium molecular dynamics (EMD) simulations between 300 and 2000 K using the Born–Mayer–Huggins interatomic potential with the partially ionic model (PIM). The thermal expansion behaviors of UO₂ and PuO₂ are well reproduced by assuming that the effective ion valence is 67.5% for PIM. The constant-pressure heat capacities deduced only by the present EMD simulation are a little smaller than experimental data. This result explains that the electronic contribution, Schottky or small polaron contribution, is not small for the heat capacity of the actinide oxide including 5f-electrons. The thermal conductivity estimated by the Green–Kubo formula under the NVE ensemble is comparable with experimental data at temperatures greater than 500 K.     

Assessment of right hepatic artery involvement in patients with biliary tract cancer using color Doppler ultrasonography

Monoclonal antibody (MAb) CC49 binds to human tumour-associated glycoprotein termed TAG-72. CC49 is a second-generation MAb with higher affinity to TAG-72 than the original MAb B72.3. CC49 was applied to 42 samples from different canine mammary tumours, belonging to seven different histopathological types. Immunoreactivity was detected by the use of an avidin-biotin complex immunoperoxidase method. Most sections from all types of mammary neoplasm reacted with this MAb. Normal tissue did not stain or stained only weakly. The results of this study suggest CC49 has selective immunoreactivity for a variety of canine mammary tumours, which seems superior to that reported with MAb 72.3. These results support the proposal for further study of diagnostic and therapeutic uses of CC49 in the management of canine mammary tumours.     

Human hepatocyte growth factor (HGF) in the aqueous humor

Previous studies have demonstrated that individuals with cystinosis, an inherited metabolic disorder, have difficulty processing visual information, and may be selectively impaired in the ability to mentally rotate figures, despite having normal IQs and normal primary sensory function. In our novel task-the 'Black Box'-subjects identified objects solely by feeling the contours. Twenty-three subjects with cystinosis, aged 4 to 34 years, were individually matched with controls on age, sex, handedness, and test form. Subjects with cystinosis performed significantly worse in identifying objects than did controls. In addition, when only subjects over 7 years of age were included, those with cystinosis took significantly longer to correctly identify objects than did controls. Our findings suggest that individuals with cystinosis have difficulty with tactile recognition of common objects. These results support the hypothesis that a genetic disorder may have specific behavioral correlates.     

Traffic Simulation in Urban Networks Using Stochastic Cell Transmission Model

The stochastic cell transmission model (SCTM) is a macroscopic traffic simulation model of high accuracy. One of its advantages is that it can represent the uncertainty of the traffic states and the changing travel demand and supply conditions. However, it has been applied to freeways and simple networks having only one origin‐destination pair. In this article, we propose a modified stochastic cell transmission model (M‐SCTM) that applies the conventional SCTM to urban networks. In M‐SCTM, we introduce vehicle agents as well as their route choice behavior on an urban network, which is more applicable to complex urban networks. Additionally, M‐SCTM was applied to networks in which the turning ratio is not priorly set through a route search algorithm. The results show that M‐SCTM can conduct simulations with as much accuracy as SCTM. Furthermore, we verified the appropriate reproducibility of the simulations based on M‐SCTM and compared the estimated value and the measured value in terms of the travel time of each vehicle.     

Biosynthesis and characterization of novel polyhydroxyalkanoate copolymers consisting of 3-hydroxy-2-methylbutyrate and 3-hydroxyhexanoate

In this study, in order to explore the possibility of biosynthesizing a novel polyhydroxyalkanoate (PHA), copolymerization of 3-hydroxy-2-methylbutyrate (3H2MB) as the α-position methylated monomer and 3-hydroxyhexanoate (3HHx) as the medium-chain-length monomer was performed to obtain P(3H2MB-co-3HHx). The β-oxidation-deficient Escherichia coli LSBJ, harboring the PHA biosynthetic operon from Aeromonas caviae and the propionyl-CoA transferase gene (pct) from Megasphaera elsdenii, was cultured with feeding tiglic and hexanoic acids as the precursors for 3H2MB and 3HHx, respectively. It was observed that pct expression was highly effective to enhance the incorporation of 3H2MB into PHA. The biosynthesized PHA was composed of 3H2MB and 3HHx units only, and the 3H2MB fraction varied in the range of 36–60 mol% depending on the culture conditions. These PHAs exhibited glass transition temperatures between ?11 to ?17 °C; moreover, no melting peak was observed during analysis using differential scanning calorimetry. This study demonstrated the biosynthesis of a hitherto unreported PHA by engineering metabolic pathway in E. coli.