In reinforced concrete (RC) structures, new-to-old concrete interfaces are widely present due to precast splices, repairs, and construction joints. In this paper, both monolithic and segmental specimens were fabricated with five kinds of water-cement ratios, including ordinary and high-strength concrete. The impressed current-accelerated corrosion test was used, and the degree of reinforcement corrosion was controlled by Faraday's Law.
View Article and Find Full Text PDFMaterials (Basel)
October 2021
The depth of cracks propagating inside reinforcement concrete (RC) components is barely able to be detected by visual inspection. Without any help from facilities, crack width can provide us with a proper way to explore the depth of cracks developing. Therefore, this paper tried to explore the correlation between crack width on the surface and crack depth.
View Article and Find Full Text PDFTritylium salts have been used as Lewis acid catalysts in organic synthesis for a long time. In this work, we found that the Lewis acid catalytic activity of tritylium ions at the node of a tensile framework is significantly improved compared to that of the free tritylium salts. The tritylium-based framework, PAF-201 (PAF, porous aromatic framework), was prepared by acidification of a semi-rigid triphenylcarbinol-based parent framework, PAF-200.
View Article and Find Full Text PDFWith the rise and development of gene therapy, it is of great significance to develop highly efficient and biocompatible polymeric gene carriers. In this work, a series of heteropolymers from ring-opening polymerization of diepoxide compounds and various functional primary amines were synthesized. The feed dosage of amines was adjusted to obtain the polymers with different functional group contents, and the structure-activity relationships of these polymers as nonviral gene vectors were examined in detail.
View Article and Find Full Text PDFThe construction of efficient and low toxic non-viral gene delivery vectors is of great significance for gene therapy. Herein, two novel polycations were constructed via Michael addition from low molecular weight polyethylenimine (PEI) 600 Da and amino acid-containing linkages. Lysine and histidine were introduced for the purpose of improved DNA binding and pH buffering capacity, respectively.
View Article and Find Full Text PDFPolycation carriers hold great potential in gene therapy. However, they usually suffer from obvious cytotoxicity and unsatisfactory transfection efficiency. In this report, a series of fluorobenzene substituted and thioacetal contained polycations (TAEA-S-xF) were prepared to explore novel alternatives for safe and efficient non-viral polymeric gene vectors.
View Article and Find Full Text PDFThe linking and modification of low molecular weight cationic polymers (oligomers) has become an attracted strategy to construct non-viral gene carriers with good transfection efficiency and much reduced cytotoxicity. In this study, PEI 600 Da was linked by biodegradable bridges containing rigid aromatic rings. The introduction of aromatic rings enhanced the DNA-binding ability of the target polymers and also improved the stability of the formed polymer/DNA complexes.
View Article and Find Full Text PDFRapid enzymatic degradation and fragmentation during DNA administration can result in limited gene expression, and consequently, poor efficacy. It is necessary to use novel vectors for DNA delivery. Herein, we aimed to design useful carriers for enhancing transfection efficiency (TE).
View Article and Find Full Text PDFZhonghua Kou Qiang Yi Xue Za Zhi
September 2005
Objective: To explore the histological change in suture of zygomatic bone for the zygomatic suture direct distraction osteogenesis.
Methods: The zygomatic bone was distracted by 3-D external distraction appliance without osteotomy. The specimens were taken 1, 3, 5 and 8 weeks after, and then examined histologically and compared with the blank contralateral side.
Br J Oral Maxillofac Surg
February 2005
Sutural expansion osteogenesis was used to extend zygomatic bone three-dimensionally by the formation of new bone in eight goats. A 3 cm incision without osteomy was made in the infraorbital part of the zygomatic bone. The external expansion appliance was then placed on the zygomatic bone.
View Article and Find Full Text PDFZhonghua Zheng Xing Wai Ke Za Zhi
May 2003
Objective: To explore a methods of 3-Dimension expansion of zygomatic suture in a goat model.
Methods: Seven goats were used in this study. The 3-D extensive applicator was designed and used to extend the zygomatic suture of the goats by placing it in the zygomatic bone through an infraorbital incision.