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121.
The paper introduces the origin of the word of Direct Digital Manufacturing and other forms of address, and the working principles of Direct Digital Manufacturing technology and major types of the technology, hard- ware and software development, use of materials, applications, market growth and its development prospects. Focused presentations of Direct Digital Manufacturing (additive manufacturing) compared to traditional mechani- cal manufacturing industry in the use of prices, processing speed, reliability and cost advantages and characteris- tics. Particularly the significant challenges and competitiveness of Direct Digital Manufacturing technology in the processing of any complexity created directly the number of objects, internal structure and channel function, as well as the shape of the chassis components and structure of the matching and optimization.  相似文献   
122.
The starch composite films (SCFs) will be one of the best alternative packaging materials to petroleum based plastic films, which mitigates white pollution and energy consumption. However, weak mechanical stability, water resistance, and dyeability has hindered the application of SCFs. Herein, a bioinspired robust SCFs with super-hydrophobicity and excellent structural colors were prepared by fiber-reinforcement and assembling SiO2/Polydimethylsiloxane (PDMS) amorphous arrays on the surface of SCFs. The properties of the designed SCFs were investigated by various methods including scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), thermo-gravimetric analysis (TGA), a tensile test, contact angle (CA) test, and an optical test. The results showed that the obtained SCFs possessed a higher tensile strength (55.17 MPa) attributed to the formed abundant hydrogen bonds between the molecular chains of the starch, cellulose fiber, and polyvinyl alcohol. Benefiting from the nanostructure with rough surface which were modified by materials with low surface free energy, the contact angle and sliding angle of the film reached up to 154° and 2°, respectively. The colors which were produced by the constructive interference of the coherent scattered light could cover all of the visible regions by tuning the diameters of the SiO2 nanoparticles. The strategy in the present study not only reinforces the mechanical strength and water resistance of SCFs but also provides an environmentally friendly way to color the them, which shows unprecedented application potential in packaging materials of the starch composite films.  相似文献   
123.
The extracellular heat shock protein 90α (eHSP90α) has been reported to promote cancer cell motility. However, whether pancreatic cancer (PC) cells expressed membrane-bound or secreted HSP90α, as well as its underlying mechanism for PC progression, were still unclear. Our study demonstrated that the amounts of secreted HSP90α proteins were discrepant in multiple PC cells. In addition, highly invasive Capan-2 cells have a higher level of secreted HSP90α compared with those of less invasive PL45 cells. The conditioned medium of Capan-2 cells or recombinant HSP90α treatment stimulated the migration and invasion of PC cells, which could be prevented with a neutralizing anti-HSP90α antibody. Furthermore, secreted HSP90α promoted elements of epithelial–mesenchymal transition in PL45 cells, including increases in vimentin and Snail expressions, decreases in E-cadherin expression, and changes in cell shape towards a mesenchymal phenotype, but these phenomena were reversed by the anti-HSP90α antibody in Capan-2 cells. In addition, high levels of low-density lipoprotein receptor-related protein 1 (LRP1) were associated with worsened patient survival in pancreatic adenocarcinoma. We demonstrated LRP1 as a receptor of eHSP90α for its stimulatory role in metastasis, by activating the AKT pathway. In addition, silencing LRP1 enhanced the chemosensitivity to gemcitabine and doxorubicin in Capan-2 cells. Therefore, our study indicated that blocking secreted HSP90α underlies an aspect of metastasis and chemoresistance in PC.  相似文献   
124.
介绍SY矿近期发生的防爆电气故障,尤其是甩掉保护、违章作业,造成防爆开关烧毁等伤人事故,并对事故原因进行了详细分析。  相似文献   
125.
126.
One-dimensional (1D) ZnO microwires were successfully synthesized by chemical vapor deposition and their structural and morphological properties were analyzed by X-ray diffraction and scanning electron microscopy, demonstrating that the microwires were single crystalline with perfect hexagonal structure and smooth surface. Using these 1D microstructures, we fabricated a novel ZnO-based ethanol gas sensor. Operating at room temperature, the sensor was found to have good sensing characteristics. The reliability and stability of the sensor could be improved by connecting multiple 1-wire devices (1-WD) in parallel into a multi-wires device. In interior natural lighting environment and under 3 V bias, the response and recovery time of the 1-WD to 200 ppm ethanol gas were <10 s and about 300 s, respectively, and the minimum and maximum detection limit were about 2 and 200 ppm, respectively. A sensing model was proposed for discussing the performance of the sensor. The simplicity in fabrication, low power consumption and low cost make the sensor suitable for practical application in many fields, especially in identifying driving under the influence and chemical industry monitoring.  相似文献   
127.
128.
从稀疏信号重建角度提出了一种改进的波达方向(DOA)估计方法。由于最小冗余线阵(MRLA)能以较少的阵元数获得较大的阵列孔径,将MRLA与l1-SVD方法相结合估计信号的DOA。仿真结果表明,经多次实验验证,所提方法是有效的,相比l1-SVD方法可以估计出更多信源的DOA,并且可以用较少的阵元数估计更多的信源DOA,具有信源过载能力。  相似文献   
129.
史宏德  叶欢  夏喜红  熊建辉 《焊管》2008,31(1):81-83
ERW(高频电阻焊)焊管的生产特点要求其在批量生产前要进行工艺评定,俗称首检。如果首检质量控制不当,会导致批量降级管的产生。分析了宝山钢铁股份有限公司宝钢分公司钢管厂610 ERW机组原有首检工艺流程存在的不足,提出了改进首检工艺流程、制作常用钢级非标准试样和标准试样力学性能对比表、提高首检夏比冲击值等措施,使首检质量和效率显著提高,取得了良好的效果。  相似文献   
130.
Small-cell lung cancer (SCLC) is the most aggressive form of lung cancer and the leading cause of global cancer-related mortality. Despite the earlier identification of membrane-proximal cleavage of cell adhesion molecule 1 (CADM1) in cancers, the role of the membrane-bound fragment of CAMD1 (MF-CADM1) is yet to be clearly identified. In this study, we first isolated MF-CADM1-specific fully human single-chain variable fragments (scFvs) from the human synthetic scFv antibody library using the phage display technology. Following the selected scFv conversion to human immunoglobulin G1 (IgG1) scFv-Fc antibodies (K103.1–4), multiple characterization studies, including antibody cross-species reactivity, purity, production yield, and binding affinity, were verified. Finally, via intensive in vitro efficacy and toxicity evaluation studies, we identified K103.3 as a lead antibody that potently promotes the death of human SCLC cell lines, including NCI-H69, NCI-H146, and NCI-H187, by activated Jurkat T cells without severe endothelial toxicity. Taken together, these findings suggest that antibody-based targeting of MF-CADM1 may be an effective strategy to potentiate T cell-mediated SCLC death, and MF-CADM1 may be a novel potential therapeutic target in SCLC for antibody therapy.  相似文献   
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