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41.
Lee Ho Jun Dao Van Hung Ma Young Wha Yu Jong Min Yoon Kee Bong 《Journal of Mechanical Science and Technology》2020,34(8):3261-3272
Journal of Mechanical Science and Technology - In this study, the effects of process parameters on the high temperature strength of 17-4PH stainless steel manufactured by selective laser melting... 相似文献
42.
Mohammadpour Hossein Pivrikas Almantas Cheng Ka Yu Ho Goen 《Journal of Applied Electrochemistry》2022,52(6):919-927
Journal of Applied Electrochemistry - Anion exchange membrane (AEM)-equipped electrochemical cells can be used for removing the carbon dioxide (CO2) from biogas, thereby upgrading its energy... 相似文献
43.
Jeongmook Lee Choah Kwon Jandee Kim Young‐Sang Youn Jong‐Yun Kim Byungchan Han Sang Ho Lim 《国际能源研究杂志》2019,43(8):3322-3329
We, for the first time, observe ZrO8 complex in Zr‐doped UO2, which is a corium structure, using experimental characterization integrated with first‐principle computational validation. Atomic level structure of U1?yZryO2 pellets (y = 0.01, 0.03, 0.05, and 0.1) is identified using Raman spectroscopy measurement and X‐ray diffraction pattern analysis. The lattice constants shrink with increasing Zr doping levels, which consistently represents in the positive shift of T2g Raman vibration peak around 445 cm?1. More interestingly, conventionally unknown new Raman peak appears around 598 cm?1, which has not been observed in neither a pure ZrO2 nor UO2 doped with tetravalent elements other than Zr. We unveil that the new peak originates from ZrO8‐type complex formed on the fluorite UO2. Our study provides precise understanding on the formation mechanisms and material properties of the corium in the hypervalent oxide. 相似文献
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Two-step sintering behavior of titanium-doped Y2O3 ceramics with monodispersed sub-micrometer powder
Two-step sintering of titanium-doped Y2O3 was carried out using monodispersed sub-micrometer powder. The effect of titanium dopant concentration on the sinterability and kinetic window of constant grain-size sintering were examined. The titanium doping improves the sinterability of the Y2O3 powder, which broadens the sintering kinetic window and lowers sintering temperature. The Vickers hardness was also enhanced as the doping concentration of titanium was increased, assuming the same grain size. 相似文献
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Sang-Chae Jeon Jae-Won Lee Joo-Young Yoon Yung-Zun Cho Dong-Joo Kim Dong Seok Kim Keon Sik Kim Jong Hun Kim Jae Ho Yang 《Ceramics International》2019,45(6):6863-6868
A reduction process in the head-end for pyroprocessing has been adopted to avoid oxidation attack on the molybdenum crucible during sintering. The reduction process is employed to reduce U3O8 pellets to UO2 prior to sintering. This allows elimination of the oxygen source, which causes oxidation attack during sintering, thereby permitting the use of a metallic crucible. However, little densification occurs due to the low reduction temperature limited by the INCONEL crucible. Consequently, the amount of material scraps from the pellets increases, thus creating an additional processing burden due to its high radioactivity. To reduce the amount of scraps, densification should be enhanced. This study suggests a simple atmospheric control strategy and clarifies its effects. With the atmospheric control, a higher bulk density and better attrition resistance were obtained in comparison to without this strategy. This can be explained in terms of O/U ratio dependent diffusion kinetics during the reduction of U3O8 to UO2. 相似文献
49.
Thomas C. van den Ende Jeroen M. M. Heuts Dr. Geoffroy P. P. Gential Marten Visser Michel J. van de Graaff Dr. Nataschja I. Ho Prof. Dr. Wim Jiskoot Dr. A. Rob P. M. Valentijn Nico J. Meeuwenoord Prof. Dr. Herman S. Overkleeft Prof. Dr. Jeroen D. C. Codée Prof. Dr. Sjoerd H. van der Burg Dr. Els M. E. Verdegaal Prof. Dr. Gijsbert A. van der Marel Prof. Dr. Ferry Ossendorp Dr. Dmitri V. Filippov 《Chembiochem : a European journal of chemical biology》2021,22(7):1215-1222
Synthetic vaccines, based on antigenic peptides that comprise MHC−I and MHC-II T-cell epitopes expressed by tumors, show great promise for the immunotherapy of cancer. For optimal immunogenicity, the synthetic peptides (SPs) should be adjuvanted with suitable immunostimulatory additives. Previously, we have shown that improved immunogenicity in vivo is obtained with vaccine modalities in which an SP is covalently connected to an adjuvanting moiety, typically a ligand to Toll-like receptor 2 (TLR2). SPs were covalently attached to UPam, which is a derivative of the classic TLR2 ligand Pam3CysSK4. A disadvantage of the triply palmitoylated UPam is its high lipophilicity, which precludes universal adoption of this adjuvant for covalent modification of various antigenic peptides as it renders the synthetic vaccine insoluble in several cases. Here, we report a novel conjugatable TLR2 ligand, mini-UPam, which contains only one palmitoyl chain, rather than three, and therefore has less impact on the solubility and other physicochemical properties of a synthetic peptide. In this study, we used SPs that contain the clinically relevant neoepitopes identified in a melanoma patient who completely recovered after T-cell therapy. Homogeneous mini-UPam-SP conjugates have been prepared in good yields by stepwise solid-phase synthesis that employed a mini-UPam building block pre-prepared in solution and the standard set of Fmoc-amino acids. The immunogenicity of the novel mini-UPam-SP conjugates was demonstrated by using the cancer patient's T-cells. 相似文献
50.
Made Angga Akwiditya Chean Yeah Yong Mohd Termizi Yusof Abdul Razak Mariatulqabtiah Kok Lian Ho Wen Siang Tan 《International journal of molecular sciences》2021,22(5)
Gene therapy research has advanced to clinical trials, but it is hampered by unstable nucleic acids packaged inside carriers and there is a lack of specificity towards targeted sites in the body. This study aims to address gene therapy limitations by encapsidating a plasmid synthesizing a short hairpin RNA (shRNA) that targets the anti-apoptotic Bcl-2 gene using truncated hepatitis B core antigen (tHBcAg) virus-like particle (VLP). A shRNA sequence targeting anti-apoptotic Bcl-2 was synthesized and cloned into the pSilencer 2.0-U6 vector. The recombinant plasmid, namely PshRNA, was encapsidated inside tHBcAg VLP and conjugated with folic acid (FA) to produce FA-tHBcAg-PshRNA VLP. Electron microscopy revealed that the FA-tHBcAg-PshRNA VLP has an icosahedral structure that is similar to the unmodified tHBcAg VLP. Delivery of FA-tHBcAg-PshRNA VLP into HeLa cells overexpressing the folate receptor significantly downregulated the expression of anti-apoptotic Bcl-2 at 48 and 72 h post-transfection. The 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay demonstrated that the cells’ viability was significantly reduced from 89.46% at 24 h to 64.52% and 60.63%, respectively, at 48 and 72 h post-transfection. As a conclusion, tHBcAg VLP can be used as a carrier for a receptor-mediated targeted delivery of a therapeutic plasmid encoding shRNA for gene silencing in cancer cells. 相似文献