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101.
102.
Objective Study on the effect of NF-κB in ox-LDL injured HUVEC-304 and the intervention with the serum of Tongmai Decoction. Methods Tongmai Decoction herbage-contained serum was made by the serum pharmacology methods, then the HUVEC-304 cells were divided into 5 groups and incubated for 24 h: 1) normal group;2) fetal calf serum group; 3) ox-LDL group; 4) simvastatin group; 5) Tongmai Decoction group. RT-PCR was used to determine the mRNA of NF-κB in the cells, Western Blot Assay was used to determine the protein content of NF-κB in the cells. Results 1) Compared with the cells in normal group and serum control group , the endothelial cells in ox-LDL group are seriously injured, while those in Tongmai Decoction group grow better; 2) Compared with the cells in normal group and fetal calf serum group, the expressions of NF-κB gene and protein are up-regulated in ox-LDL group(P<0.05, P<0.01); 3) Compared with the cells in ox-LDL group, the expression of NF-κB gene and protein in Tongmai Decoction group are significantly down-regulated, there is no difference between Tongmai Decoction group and simvastatin group(P>0.05). Conclusion Tongmai Decoction can protect the injured endothelial cells, up-regulate the expressions of NF-κB gene and protein content.  相似文献   
103.
Blended SRC-II process streams, representing a full boiling range distillate material, were fractionally distilled into non-overlapping 50 °F cuts with boiling points between 300 and 850 °F. Another set of 18 distillate cuts were obtained with boiling points ranging between 138 and 1055 °F. Distillate cuts were assayed for mutagenic activity using the histidine reversion assay with Salmonella typhimurium strains TA98, TA100, TA1535 and TA1537, as well as for mammalian-cell transformation activity in the Syrian hamster embryo test, and DNA damage in the prophage induction assay. Samples were also separated into chemical class fractions by alumina column chromatography and analysed by high resolution gas chromatography so that the chemical composition of the cuts could be related to their relative activity in the different assays. In the mammalian cell transformation and microbial mutagenicity assays, significant activity was found almost exclusively in distillate cuts with components boiling > 700 °F, with the highest activity in the transformation assay observed for cuts > 800 °F. All of the distillate cuts showed increased levels of DNA damage as expressed by lambda prophage induction in Escherichia coli 8177. However, the greatest activity was associated with distillate cuts with boiling points in the 800 °F + range. Chemical analysis of the 50 °F distillate cuts showed a variety of polycyclic aromatic hydrocarbons (PAH) and amino-PAH compounds to be present in the distillate cuts boiling > 700 °F and essentially absent from cuts boiling < 700 °F. The sample set of non-overlapping (50 °F) cuts were reblended according to the proportions of each cut found in the original blend material. These reblended composites were then assayed to compare their activity with that predicted from the activities of the component distillate cuts. The reblending experiments indicated the microbial mutagenicity response was essentially additive. Mammalian cell transformation activities were non-additive, indicating a compositional effect on the expression of transforming agents in the complex mixture.  相似文献   
104.
A new method of studying the corrosion inhibition mechanism of rare earth metal(REM) on LC4 Al alloy with the spilt cell technique was studied. The principle and experimental method of the spilt cell technique were analyzed. By measuring the change of net-electric current between the two electrodes caused by the change of the amount of oxygen in the solution and the addition of CeCl3, the influence of corrosive performance of CeCl3 on LC4 super-power aluminum alloy in the 0.1 mol·L−1 NaCl solution was investigated. Meanwhile, the conditional changes of pH values, CeCl3 solution, additire and time of performance were also studied. Finally, the features of electrode surface were revealed by using SEM and X-ray energy-dispersive spectrometry (EDS). By combining these with other electric chemical techniques, such as potential-time curve, polarization curve et al.  相似文献   
105.
We report on the use of pulsed plasma-enhanced chemical vapor deposition (P-PECVD) technique and show that “state-of-the-art” amorphous silicon (a-Si:H) materials and solar cells can be produced at a deposition rate of up to 15 Å/s using a modulation frequency in the range 1–100 kHz. The approach has also been developed to deposit materials and devices onto large area, 30 cm×40 cm, substrates with thickness uniformity (<5%), and gas utilization rate (>25%). We have developed a new “hot wire” chemical vapor deposition (HWCVD) method and report that our new filament material, graphite, has so far shown no appreciable degradation even after deposition of 500 μm of amorphous silicon. We report that this technique can produce “state-of-the-art” a-Si:H and that a solar cell of p/i/n configuration exhibited an initial efficiency approaching 9%. The use of microcrystalline silicon (μc-Si) materials to produce low-cost stable solar cells is gaining considerable attention. We show that both of these techniques can produce thin film μc-Si, dependent on process conditions, with 1 1 1 and/or 2 2 0 orientations and with a grain size of approx. 500 A. Inclusion of these types of materials into a solar cell configuration will be discussed.  相似文献   
106.
LiFePO4 is a potential candidate for the cathode material of the lithium secondary batteries. A co-precipitation method was adopted to prepare LiFePO4 because it is simple and cheap. Nitrogen gas was needed to prevent oxidation of Fe2+ in the aqueous solution. The co-precipitated precursor shows the high reactivity with the reductive gas, and the single phase of LiFePO4 is successfully synthesized with the aid of carbon under less reductive conditions. LiFePO4 fine powder prepared by co-precipitation method shows high rate capability, impressive specific capacity and cycle property.  相似文献   
107.
合成了N-异丙基丙烯酰胺(NIPAAm)与葡聚糖的共聚水凝胶,利用红外光谱表征了单体和凝胶结构,研究了水凝胶在去离子水和细胞培养基中的温度响应性,并对凝胶进行了细胞培养和脱附研究.结果表明,共聚凝胶具有很好的温度敏感性和细胞相容性,可以通过控制温度变化,实现对细胞的无损伤脱附.  相似文献   
108.
通过交流阻抗方法研究了熔融碳酸盐燃料电池阴极材料锂镍氧化物、锂钴氧化物和锂铁氧化物的导电性能。结果表明:锂镍氧化物电极的导电性最好,锂钴氧化物电极的导电性次之,锂铁氧化物电极的导电性最差;它们的导电性都随着温度的升高而按指数规律增加;在合成锂钴氧化物(或锂铁氧化物)的过程中,使Li2CO3轻微过量,可以提高锂钴氧化物(或锂铁氧化物)电极的导电性,而且在同一温度下,随着nLi∶nCo(或nLi∶nFe,摩尔比)值的增大,锂钴氧化物(或锂铁氧化物)电极的导电性显著增加。  相似文献   
109.
In the present work 316LN as well as 316 stainless steel (SS) coupons each of dimensions (0.025 × 0.018 × 0.006 m3) in well-polished condition were used as two nominal electrodes which were immersed in the aerated solution of 0.5 M NaCl. Correlated current and potential electrochemical noise (EN) signals were collected at 1 Hz sampling frequency for 1 h daily over a period of 30 days. The detrended EN data were used to calculate the noise resistance (R N) as well as the spectral noise resistance at zero frequency (R SNo) values and other statistical parameters. To study the nature of pits and distribution of their diameters as well as depths, extensive observations of the pitted and the blank specimens were carried out using Confocal Laser Scanning Microscopy (CLSM). The current and the potential records of the two alloys showed distinct differences in their corrosion behavior. It was observed that within less than 4 h of immersion, 316SS showed signals indicative of unstable pitting and onset of stable pitting was noticed after 48 h of exposure. However, until about 24 h, 316LN showed just the random signals and unstable pitting was observed after 28 h. The signals clearly indicated continuous growth of the stable pits in 316SS as against the repassivation of the unstable pits in 316LN after 7 days exposure. It was observed that R N values showed a continuous decrease in the case of 316SS, but were quite stable in the case of 316LN over the exposure period. Concurrent to these observations it was observed that 316SS specimen was extensively pitted. The frequency distributions of pit diameters as well pit depths were observed to be highest at 10-20 μm and 5-10 μm, respectively. However, pits with as large as 70-80 μm diameter and as deep as 20-25 μm too were observed. No pits were observed in case of 316LN even after 30 days of exposure, an observation that corroborates well with the stable R N values. Thus, in the present investigation, the long-term tests using EN technique coupled with CLSM studies conclusively prove that many unstable pits initiated in 316SS turn into stable ones resulting in insidious localized corrosion attack whereas the unstable pits initiated in 316LN get passivated in the simulated coastal environment.  相似文献   
110.
As a powerful method for the study of mechanical properties at micro-/nanoscale, nanoindentation was applied to measure the hardness and elastic modulus of bacteria-templated metallic nanomaterials for the first time. Based on the morphological characterization by Atomic Force Microscopy (AFM) and Transmission Electron Microscopy (TEM), nanoindentation testing results showed that after coating with nickel via electroless chemical plating, the elastic modulus and hardness of bacterial cells were increased about 17 times and 50 times, respectively, indicating a great improvement in mechanical properties. This study would lay a forceful mechanical foundation for a better and general understanding of this kind of biotemplated metallic nanomaterials, which showed potential applications in nanoelectronics, nanomagnetism and nanomechanics.  相似文献   
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