The twin monomer 2,2'-spirobi[4H-1,3,2-benzodioxasiline] (1) can be polymerized to nanostructured SiO2/phenolic-resin composite material by thermally induced twin polymerization. Thermally induced twin polymerization represents a way to produce nanocomposites simply by thermal induction of twin monomers. Besides 1, the thermal reaction of several related salicylic (2-oxybenzylic) silicon molecules has been investigated. The thermal cleavage of the molecules is studied by using several trapping reagents (e.g., vinyl compounds). A significant occurrence of quinone methide adducts indicates that the thermal mechanism proceeds not only by a ring opening at the oxymethylene position, but also with the ortho-quinone methide as a central or alternative intermediate. This is supported by product analyses of thermally initialized reactions of 1 and its substituted analogues as well as by quantum chemical calculations.
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http://dx.doi.org/10.1002/chem.201400038 | DOI Listing |
Nano Lett
January 2025
Key Lab for the Physics and Chemistry of Nanodevices and Center for Carbon-based Electronics, School of Electronics, Peking University, Beijing 100871, China.
One-time programmable (OTP) memory is an essential component in chips, which has extremely high security to protect the stored critical information from being altered. However, traditional OTP memory based on the thermal breakdown of the dielectric has a large programming current, which leads to high power consumption. Here, we report a gate tunneling-induced "cold" breakdown phenomenon in carbon nanotube (CNT) field-effect transistors, and based on this we construct a "cold" fuse (C-fuse) memory where applying a mild gate voltage can break down the CNT channel without damaging the gate dielectric.
View Article and Find Full Text PDFJ Pharm Anal
October 2024
Department of Dermatology, The Third Hospital of Hebei Medical University, Shijiazhuang, 050051, China.
Tetrandrine (TET), a natural bisbenzyl isoquinoline alkaloid extracted from S. Moore, has diverse pharmacological effects. However, its effects on melanoma remain unclear.
View Article and Find Full Text PDFFood Res Int
February 2025
Institute of Food Science and Technology, Chinese Academy of Agriculture Sciences/ Comprehensive Utilization Laboratory of Cereal and Oil Processing, Ministry of Agriculture and Rural Affairs, Beijing 100193, China.
Improving the content and physicochemical properties of soluble dietary fiber (SDF) in wheat bran (WB) is conducive to enhancing the palatability and processing adaptability of bran-containing products. In this study, induced electric field (IEF) was employed for the modification of WB. The IEF modification conditions were optimized, and the effects on the structural and physicochemical properties of WB and its SDF were evaluated.
View Article and Find Full Text PDFNat Methods
January 2025
Department of Bioengineering, University of Pennsylvania, Philadelphia, PA, USA.
Inducible protein switches are currently limited for use in tissues and organisms because common inducers cannot be controlled with precision in space and time in optically dense settings. Here, we introduce a protein that can be reversibly toggled with a small change in temperature, a stimulus that is both penetrant and dynamic. This protein, called Melt (Membrane localization using temperature) oligomerizes and translocates to the plasma membrane when temperature is lowered.
View Article and Find Full Text PDFInt J Biol Macromol
January 2025
Pasteur Institute of Iran, Faculty of Bioscience and Biotechnology, Tehran, Iran.
In recent years, attempts were made to develop biomaterials using synthetic and natural polymers to induce osteogenesis of human mesenchymal stem cells (hMSCs). Poly(ε-caprolactone) (PCL) is one of the few synthetic polymers with the potential to differentiate hMSCs to bone. However, its potential is limited, attributed to its low strength; its fast crystallization rate also compromises its dimensional stability.
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