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91.
严加根  苗旺  王荣和 《轧钢》2021,38(3):38-42
针对酸洗-冷连轧联合机组生产中焊缝断带现象,分析得到其主要影响因素是热轧原料质量,主要表现为焊接处前后卷带钢厚度差较大,导致在冷轧过程中焊缝位置应力集中而断带.通过综合各项影响因素,建立了焊缝断带预测模型,实现了热轧产品质量数据以及冷轧生产计划的收集、存储,以及跨工序应用.在焊缝断带概率预测模型的基础上,建立了带钢头尾...  相似文献   
92.
为提高鱼雷非接触爆炸对水下目标的毁伤效果,提出一种新的鱼雷爆-破串联聚能战斗部的设计方案,前级为爆炸装药,后级为聚能装药,利用前级爆炸产生的气泡为后级的爆炸成型弹丸(EFP)提供前进通道,有效降低EFP的飞行阻力和能量损耗。采用AUTODYN数值计算软件,模拟EFP在空气、水和气泡中飞行情况,对比分析了EFP的速度变化和变形及对靶板的毁伤情况,验证了此设计方案的可行性和优越性。  相似文献   
93.
双层药型罩侵彻体形成过程的数值仿真   总被引:1,自引:0,他引:1  
为了找出一种适合于串联侵彻体形成及侵彻过程研究的数值方法,使用AUTODYN流体代码对双层罩在爆轰产物作用下的形成规律进行了数值仿真.数值仿真的目的是比较Lagrange算法、Euler-Lagrange Coupling算法和Euler算法,这3种算法哪种更适合于研究该文的物理情况.研究对象是由一个主装药和两层药型罩...  相似文献   
94.
Parasitic absorption in transparent electrodes is one of the main roadblocks to enabling power conversion efficiencies (PCEs) for perovskite‐based tandem solar cells beyond 30%. To reduce such losses and maximize light coupling, the broadband transparency of such electrodes should be improved, especially at the front of the device. Here, the excellent properties of Zr‐doped indium oxide (IZRO) transparent electrodes for such applications, with improved near‐infrared (NIR) response, compared to conventional tin‐doped indium oxide (ITO) electrodes, are shown. Optimized IZRO films feature a very high electron mobility (up to ≈77 cm2 V?1 s?1), enabling highly infrared transparent films with a very low sheet resistance (≈18 Ω □?1 for annealed 100 nm films). For devices, this translates in a parasitic absorption of only ≈5% for IZRO within the solar spectrum (250–2500 nm range), to be compared with ≈10% for commercial ITO. Fundamentally, it is found that the high conductivity of annealed IZRO films is directly linked to promoted crystallinity of the indium oxide (In2O3) films due to Zr‐doping. Overall, on a four‐terminal perovskite/silicon tandem device level, an absolute 3.5 mA cm?2 short‐circuit current improvement in silicon bottom cells is obtained by replacing commercial ITO electrodes with IZRO, resulting in improving the PCE from 23.3% to 26.2%.  相似文献   
95.
对串联战斗部前级聚能装药开孔不大的问题开展了研究,提出了一种M型药型罩,通过分析该药型罩结构设计的原理,运用ANSYS/LS-DYNA仿真软件对该药型罩形成环形聚能射流进行了数值模拟研究。结果表明:M型药型罩能够形成直径较大的环形射流,射流持续稳定;军用领域,能够用作串联战斗部的前级药型罩,对靶板切割成一定孔深且孔径大的环形孔,方便后级随进战斗部对靶板形成充塞破坏;民用领域,可以对一定厚度的靶板进行快速打孔。  相似文献   
96.
We developed tetranucleotide-repeat microsatellite markers for the masu salmon (Oncorhynchus masou) complex. 454 pyrosequencing was used to discover repeat motifs, and seven polymorphic microsatellite-primer sets were identified. The number of alleles detected at each locus ranged from four to 24 and the expected heterozygosity varied from 0.57 to 0.92. Cross-subspecies amplification for O. m. masou, O. m. ishikawae and O. m. subsp. was successful. These microsatellites can be utilized in studies of genetic structure, genetic diversity, and intra- and inter-subspecific hybridization, making a contribution to conservation and management of the Oncorhynchus masou complex.  相似文献   
97.
98.
4-Vinylsyringol, also referred to as canolol, is a highly active antioxidant and potent lipidperoxyl radical scavenger found in rapeseed. The canolol content of rapeseed can be increased through the decarboxylation of sinapic acid via roasting treatments. Different roasting conditions were tested and compared and an optimum for the canolol formation was found at 160 °C. The canolol content of the rapeseed samples with optimal roasting increased by a factor of 120 in relation to the unroasted sample. The rapeseed was ground, extracted and analysed by normal-phase HPLC/UV. The structure of canolol was confirmed by NMR and MS techniques. Several rapeseed oils were purchased in German food stores and analysed. No differences in canolol content were observed in both cold-pressed and rape kernel oil samples tested. Dehulled rapeseed samples demonstrated no significant difference in canolol content when compared to unpeeled rapeseed samples.  相似文献   
99.
Listeria monocytogenes is the causative bacteria of listeriosis, a type of food poisoning with high mortality, which mainly infects people through the consumption of ready-to-eat food. Most cases of L. monocytogenes contamination have occurred at food processing plants. Therefore, food companies must carefully monitor the proliferation and spread of this bacterium. Listeria innocua has often been reported to exist in food processing plants when the presence of the genus Listeria is investigated. In addition, because L. innocua and L. monocytogenes are known to act together, L. innocua is an important hygiene indicator for food companies. Multilocus variable-number tandem repeat analysis (MLVA) is a method used to discriminate between strains, based on the discrepancies in the number of repeating units within the tandem repeats (TRs). In many cases, MLVA uses capillary electrophoresis (CE) or base sequence analysis. However, the equipment used for these analyses is expensive, and requires a certain level of knowledge and skill for operation. Therefore, it is only used at research facilities. However, in order to rapidly trace the sources of contamination in food processing plants, it is necessary to easily discriminate between strains within the working areas. Therefore, in this study, we established a simpler MLVA method, using high resolution melting analysis (HRMA) to analyze the diversity of variable-number of tandem repeats (VNTRs). We investigated three VNTR loci (used in a previous MLVA-CE analysis) using MLVA-HRMA. The MLVA-HRMA of 23 L. innocua strains showed that this method differentiates between strains at a more or less equal level with MLVA, which uses base sequence analysis. HRMA is also used to investigate gene polymorphisms based on the Tm value of the PCR products. Therefore, a different peak pattern is observed depending on the internal SNP even if the number of repeating units are the same. We then evaluated the efficacy of MLVA-HRMA in differentiating between 96 strains isolated at food processing plants. This analysis demonstrated the usefulness of the MLVA-HRMA method and its discriminatory ability in tracing the sources of contamination in food processing plants. Since this method is simpler, and cheaper than the existing MLVA methods, it could see widespread use in food processing plants as a rapid investigative tool.  相似文献   
100.
The angiotensin I‐converting enzyme (ACE)‐inhibitory activities of catfish (Clarias batrachus) muscle protein hydrolysates were investigated. Thermolytic digests of C. batrachus sarcoplasmic and myofibrillar proteins exhibited inhibitory activity towards ACE and were purified with the aim of ultrafiltration, gel filtration and reversed‐phase high‐performance liquid chromatography (RP‐HPLC). The amino acid sequences of hydrolysates with the highest ACE‐inhibitory activities were determined using electrospray quadrupole time‐of‐flight tandem mass spectrometry (ESI‐TOFQ MS/MS). The sequences of GPPP (IC50 = 0.86 μm ) and IEKPP (IC50 = 1.2 μm ) corresponding to the fragments 986–989 and 441–445 of myosin‐I heavy chain were identified for the sarcoplasmic and myofibrillar protein hydrolysates, respectively. Peptide GPPP exhibited a mixed‐type inhibition whereas peptide IEKPP could only bind to the active sites of ACE. The results demonstrate that hydrolysates of C. batrachus muscle proteins obtained by thermolysin may contain bioactive peptides.  相似文献   
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