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51.
应用有限元模拟仿真计算,对相变诱发塑性(TRIP)带钢在连轧机精轧后由850~890℃快冷至700℃,经几秒钟短暂空冷再第2次快速水冷至卷取温度400℃的冷却过程的温度进行了分析计算。分析结果得出,3mmTRIP带钢厚度方向的温差较小,而8mmTRIP带钢厚度方向温差明显增大。因此TRIP带钢在2次快速冷却后和卷取前应有适当的空冷时间以降低TRIP带钢卷取时表面和厚度方向中心处的温度差。  相似文献   
52.
The impact of neurodegenerative diseases (ND) is becoming unbearable for humankind due to their vast prevalence and the lack of efficacious treatments. In this scenario, we focused on imidazoline I2 receptors (I2-IR) that are widely distributed in the brain and are altered in patients with brain disorders. We took the challenge of modulating I2-IR by developing structurally new molecules, in particular, a family of bicyclic α-iminophosphonates, endowed with high affinity and selectivity to these receptors. Treatment of two murine models, one for age-related cognitive decline and the other for Alzheimer’s disease (AD), with representative compound B06 ameliorated their cognitive impairment and improved their behavioural condition. Furthermore, B06 revealed beneficial in vitro ADME-Tox properties. The pharmacokinetics (PK) and metabolic profile are reported to de-risk B06 for progressing in the preclinical development. To further characterize the pharmacological properties of B06, we assessed its neuroprotective properties and beneficial effect in an in vitro model of Parkinson’s disease (PD). B06 rescued the human dopaminergic cell line SH-SY5Y from death after treatment with 6-hydroxydopamine (6-OHDA) and showed a crucial anti-inflammatory effect in a cellular model of neuroinflammation. This research reveals B06 as a putative candidate for advancing in the difficult path of drug discovery and supports the modulation of I2-IR as a fresh approach for the therapy of ND.  相似文献   
53.
Large-grained and 7 μm thick CdTe film has been fabricated on top of Mo coated soda-lime glass substrate. As a new approach the dynamic recrystallization process (DRC) was used to form the structure of films. For the characterization of the structure and composition of the films a scanning electron microscopy (SEM), energy dispersive X-ray microanalysis (EDS) and X-ray diffraction (XRD) methods were used. The changes in the structure of films were studied in accordance with the process temperature, pressure and as-deposited film thickness. Significant changes in the CdTe film were observed after DRC of deposited films at the process temperatures between 450 °C and 550 °C. EDS quantitative analysis showed that during the recrystallization the Mo and CdTe films composition remained stable for all studied samples. The XRD results showed that the increase in the process temperature caused improvement in orientation of the films along direction of (111). The DRC temperature above 550 °C reduced the orientation again. The limits of the temperature and pressure in application of soda-lime glass in DRC were found and discussed.  相似文献   
54.
Experimental verification of the mathematical surface roughness model for sputtered silicon was performed. The beam shape and its significant level of intensity were determined first by measuring the topography of craters sputtered by focused ion beam (FIB). Then the beam function was generated for various combinations of beam parameters. The material function was developed both by theoretical and experimental analysis. These two functions were then used in the model to calculate the theoretical surface roughness. Microsurface analysis was formed by FIB sputtering of a (100) silicon wafer. The surface roughness at the bottom of the sputtered features was then measured using an atomic force microscope. The theoretical surface roughness was found to be within ±1 and ±5 nm of the measured surface roughness with the measurement uncertainty (standard deviation) of about ±0.36 and ±0.85 nm for Ra and Rt, respectively.  相似文献   
55.
In microbiological research, it is important to understand the time course of each step in a pathogen’s lifecycle and changes in the host cell environment induced by infection. This study is the first to develop a real-time monitoring system that kinetically detects luminescence reporter activity over time without sampling cells or culture supernatants for analyzing the virus replication. Subgenomic replicon experiments with hepatitis C virus (HCV) showed that transient translation and genome replication can be detected separately, with the first peak of translation observed at 3–4 h and replication beginning around 20 h after viral RNA introduction into cells. From the bioluminescence data set measured every 30 min (48 measurements per day), the initial rates of translation and replication were calculated, and their capacity levels were expressed as the sums of the measured signals in each process, which correspond to the areas on the kinetics graphs. The comparison of various HuH-7-derived cell lines showed that the bioluminescence profile differs among cell lines, suggesting that both translation and replication capacities potentially influence differences in HCV susceptibility. The effects of RNA mutations within the 5′ UTR of the replicon on viral translation and replication were further analyzed in the system developed, confirming that mutations to the miR-122 binding sites primarily reduce replication activity rather than translation. The newly developed real-time monitoring system should be applied to the studies of various viruses and contribute to the analysis of transitions and progression of each process of their life cycle.  相似文献   
56.
目的 研究不同菌材培养料对茶树菇(Agrocybe chaxingu)生长特性和营养品质影响。方法 以贵州常见菌材构树(Broussonetia papyrifera)、刺槐(Robinia pseudoacacia)、光皮桦(Betula luminifera)、青冈(Quercus glauca)为栽培料,测定比较木材理化特性对茶树菇农艺性状及粗蛋白、多糖、粗脂肪、矿质元素和氨基酸含量的影响。结果 4种菌材对茶树菇菌丝生长速率影响不显著;构树培养茶树菇农艺性状最佳,其次为光皮桦;刺槐培养茶树菇粗脂肪和多糖含量最丰富。青冈培养茶树菇常量元素K、Mg、Ca、Na含量最高,构树培养茶树菇微量元素Fe、Zn、Cu含量最高;光皮桦培养茶树菇总氨基酸、必需氨基酸和限制性氨基酸含量最高。粗蛋白、Cu、Fe、Zn、苯丙氨酸、缬氨酸、Ca、Mg、苏氨酸、多糖、粗脂肪、K依次为区分4种菌材培养茶树菇主要指标。菌丝生长速率与全氮含量呈负相关性,培养基中菌丝生长速率与菌材半纤维素含量呈显著正相关性;子实体重量与木质素含量呈显著正相关性。结论 菌材理化性质对茶树菇生长及营养品质具有显著影响。构树和青冈培育茶...  相似文献   
57.
利用复合方法研制出一种LPTC电子陶瓷材料,并经作温度敏感元件,研制出适合井下恶劣环境,精度高、寿命长的温度传感器。并对探头包封和响应时间以及传感器的动、静态特性进行了测量。  相似文献   
58.
基于有限元法的染污直流支柱复合绝缘子伞裙参数优化   总被引:2,自引:0,他引:2  
直流支柱绝缘子污闪问题比交流支柱绝缘子要严重,通过伞裙优化能够明显改善其污闪特性。该文借鉴人工污秽试验研究伞裙优化的成果,利用有限元法对染污直流支柱绝缘子建模,研究伞间距、大伞伸出和大小伞伸出差对绝缘子沿面电场分布的影响。提出以爬电距离和电场强度作为伞裙参数优化的判断依据,研究表明,电场强度分布随着伞裙参数的变化呈有规律变化:随着伞间距的增加,绝缘子沿面平均电场强度逐渐减小;随着大伞伸出的增加,绝缘子沿面平均电场强度逐渐增大;随大小伞伸出差增加,爬电系数单调减小,沿面平均电场强度呈振荡减小的趋势。通过比较分析得出支柱绝缘子伞裙较优的参数范围,为进行伞裙优化试验研究提出试品伞裙的建议参数。  相似文献   
59.
基于通用型线的涡旋压缩腔几何模型   总被引:6,自引:0,他引:6  
根据对应的节线类型把压缩腔分为a、b两类,定义涡旋压缩腔的宽度、长度和法面面积,用解析法建立以型线、压缩腔形状变化、生命周期和压缩腔数综合的涡旋压缩腔几何模型,分析压缩腔的宽度、长度、面积、体积、质心、啮合点的曲率半径等几何特性.研究表明:所建立的几何模型能真实反映压缩腔的形成、变形、破灭等过程,表征涡旋压缩腔的运动特征,可对压缩腔几何特性进行全面分析,是涡旋压缩腔几何学、运动学、动力学、热力学、仿真等研究以及设计的基础;Ⅲ类型线的压缩腔变化过于复杂,Ⅱ类型线的压缩腔变形及动力特性稳定,Ⅰ类型线的压缩腔变形效率高,加工相对容易,因此实践中宜采用以Ⅰ类型线为基础而中心啮合部分为Ⅱ类型线的组合型线.  相似文献   
60.
工艺参数对马氏体不锈钢激光冲击区表面轮廓的影响   总被引:1,自引:0,他引:1  
激光功率密度和搭接率对马氏体不锈钢的激光冲击区的表面轮廓有较大影响.激光功率密度从3.79 GW/cm2到7.25 GW/cm2,冲击区塑性变形程度随功率密度增大而增大,当激光功率密度为6.09 GW/cm2时,冲击区塑性变形程度适中,其残余应力平均值达-569.1 MPa.搭接率试验结果表明,搭接率为33%时,可获得较大面积无挤出的激光冲击区,无挤出区域的塑性均匀,变形深度波动幅度在2μm以内,而且此搭接率下冲击区挤出面积较小,分布具有规律,便于再次冲击以降低冲击区的表面波纹度.  相似文献   
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