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101.
1 INTRODUCTIONTheorthorhombicalloysareofgreattech nolog icalinterestinhightemperatureapplicationssincetheyhaveagoodbalanceamongst  相似文献   
102.
彭发云 《铸造技术》2004,25(10):785-787
用呋喃树脂石英砂工艺生产牵引电机换向器套筒出现变形、裂纹等铸造缺陷,是由石英砂相变膨胀引起,后用高铬刚玉砂代替石英砂得到解决.  相似文献   
103.
Immune checkpoint inhibitors (ICIs) have demonstrated remarkable efficacy in a growing number of malignancies. However, overcoming primary or secondary resistances is difficult due to pharmacokinetics issues and side effects associated with high systemic exposure. Local or regional expression of monoclonal antibodies (mAbs) using gene therapy vectors can alleviate this problem. In this work, we describe a high-capacity adenoviral vector (HCA-EFZP-aPDL1) equipped with a mifepristone-inducible system for the controlled expression of an anti-programmed death ligand 1 (PD-L1) blocking antibody. The vector was tested in an immune-competent mouse model of colorectal cancer based on implantation of MC38 cells. A single local administration of HCA-EFZP-aPDL1 in subcutaneous lesions led to a significant reduction in tumor growth with minimal release of the antibody in the circulation. When the vector was tested in a more stringent setting (rapidly progressing peritoneal carcinomatosis), the antitumor effect was marginal even in combination with other immune-stimulatory agents such as polyinosinic-polycytidylic acid (pI:C), blocking mAbs for T cell immunoglobulin, mucin-domain containing-3 (TIM-3) or agonistic mAbs for 4-1BB (CD137). In contrast, macrophage depletion by clodronate liposomes enhanced the efficacy of HCA-EFZP-aPDL1. These results highlight the importance of addressing macrophage-associated immunoregulatory mechanisms to overcome resistance to ICIs in the context of colorectal cancer.  相似文献   
104.
The characterization of La x Sr1−x MnO3 powders produced by spray pyrolysis using scanning electron microscopy (SEM) and transmission electron microscopy (TEM) observation, specific surface area (Brunauer-Emett-Teller), and particle size distribution measurements shows that the resultant large particles are loose agglomerates consisting of many small particles. However, the sintered tiny particles can form hard agglomerates, and the particle size increases remarkably. The structures of the powders before and after sintering were identified by x-ray diffraction (XRD). The study of the electrical property of the powder shows that the powder is a metallic conductor. In a reducing atmosphere, the powder can be decomposed. When the powder is cofired with yttria-stabilized zirconia 5% (YSZ) powder at 1200 °C for 5 h, no new phase is produced, and the powder remains a single provskite hexagonal-rhombohedral structure.  相似文献   
105.
Highly conductive transparent aluminium-doped ZnO (ZnO:A1) films were successfully deposited by CW-CO2 laser-induced evaporation. Optimisation of evaporation parameters was based on laser power, substrate temperature, O2 partial pressure in the vacuum chamber and amount of Al in the ZnO source pellet. ZnO:A1 films with an electrical resistivity as low as 6.6 × 10−2Ω·cm and an optical transmission of 80% at 500nm were obtained at laser power of 15 W, substrate temperature of about 200°C, O2 partial pressure of 6—7 × 10−4 Torr and 5wt.% Al. Conductivity of ZnO films can be increased one order via Al-doping in ZnO films. The films obtained by laser-induced evaporation have compared quite favorably with the high quality films obtained by sputtering.  相似文献   
106.
孙春亮 《轻金属》2005,(9):26-28
针对铝电解原材料中AlF3与Al2O3自动配料不准和难于观察及控制的现象,我厂开发应用了AlF3贮仓料位计,并与微机网络相连,实现了远程测量与在线监控,使AlF3配料更准确更均匀,电解质分子比更稳定,电解槽生产低耗高效。  相似文献   
107.
Potassium channels: a computer prediction of structure and selectivity   总被引:3,自引:0,他引:3  
Model structures for the pore of the potassium channels Shakerand ROMK1 are predicted. The models arise from computer simulationsand suggest reasons for the striking selectivity of these channelsfor K+ and the blocking of ROMK1 by internal Mg2+. The modelledstructure of the Shaker pore is supported by mutagenesis data.The mutagenesis experiments indicate the side chains responsiblefor binding to blocking agents [tetraethylammonium (TEA) andcharybdotoxin (CTX)] and the model has these side chains suitablyoriented for binding. An aromatic K+ binding site part way downthe pore is also predicted by the Shaker pore model.  相似文献   
108.
稳定态二氧化氯杀菌剂的制备及应用   总被引:3,自引:0,他引:3  
稳定态二氧化氯(C1O2)是一新型杀菌消毒剂,具有高效、广谱、安全的特性,适用范围广,不产生对人体有害物质。介绍了稳定态ClO2的性质、检测、制备条件及其在有关领域的应用。  相似文献   
109.
杨丽娟  李俊峰  徐蓉  林军 《农药》2004,43(11):518-519
采用生长速率法测定了不同浓度的百菌清及其三氟衍生物对番茄早疫病菌Alternaria solani(Ell,et Mart.)Jones es Gmut的室内杀菌毒力。试验结果表明,百菌清及其三氟衍生物的ED50值分别为6089.89mg/L和156.43mg/L。,前者是后者的38.93倍。百菌清三氟衍生物的毒力明显高于百菌清。  相似文献   
110.
High resolution XPS analysis of chemical functionalised multi-wall carbon nanotubes (MWCNTs) and single wall carbon nanotubes (SWCNT) was done with ESCA300 (overall instrument resolution of 0.35 eV). Information to the degree of functionalisation was ascertained by argon ion bombardment of the samples followed by XPS analysis to detect the functional groups, the percentage atomic concentration of various elements present and whether or not the detected functional groups imposed a chemical shift on the CNT atoms. The results show that true chemical functionalisation was achieved and by argon ion bombardment these functional groups can be altered relative to the C 1s carbon atoms of the CNT. The choice of chemicals used for functionalisation, the techniques employed and the types of nanotubes treated are important factors in chemical characterisation. The carbon atom on the nanotube ring to which the functional group (atom) is bonded, the chirality of the CNT, the electronegativity of the functional group, the bond type and whether the CNT is single-wall or multi-wall, or cut (short) could play a role in determining the chemical shift on the CNTs atoms. These investigations are relevant to chemical functionalisation of carbon nanotubes for various applications for example DNA sensors and other biomedical sensors.  相似文献   
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