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This study paves the way toward a new class of lightweight and robust porous carbon nanocomposites for application in electrochemical energy storage systems and oil sorption devices.Mesoporous silica-based nanoparticles (MSNs) have gained rapid interest as a drug delivery system (DDS) and demonstrated their versatility in delivering drugs for the treatment of various cancers. However, the drug loading efficiency of MSNs is low and is usually improved by improving textural properties through complicated synthesis methods or by post synthesis modification of the surface that can result in the loss of surface area and modify its drug release properties. In this study, we report a direct single-step synthesis of MSNs with a unique egg-yolk core-shell morphology, large pore volume and a hydrophilic surface, decorated with nitrogen rich surface functionalities for increasing its drug loading capacity. This combination of excellent textural properties and surface functionalisation was achieved by a simple soft templating method using dual surfactants and the silica sources assisted by employing either triethylamine (TEA) or triethanolamine (TEO) as the hydrolysis agent. The morphology and well- implemented as an effective carrier of chemotherapeutic drugs.Health concerns associated with the advent of nanotechnologies have risen sharply when it was found that particles of nanoscopic dimensions reach the cell lumina. Plasma and organelle lipid membranes, which are exposed to both the incoming and the engulfed nanoparticles, are the primary targets of possible disruptions. However, reported adhesion, invagination and embedment of nanoparticles (NPs) do not compromise the membrane integrity, precluding direct bilayer damage as a mechanism for toxicity. Here it is shown that a lipid membrane can be torn by small enough nanoparticles, thus unveiling mechanisms for how lipid membrane can be compromised by tearing from nanoparticles. Surprisingly, visualization by cryo transmission electron microscopy (cryo-TEM) of liposomes exposed to nanoparticles revealed also that liposomal laceration is prevented by particle abundance. Fasudil in vitro Membrane destruction results thus from a subtle particle-membrane interplay that is here elucidated. This brings into a firmer molecular basis the theorized mechanisms of nanoparticle effects on lipid bilayers and paves the way for a better assessment of nanoparticle toxicity.The aldol reaction of p-nitrobenzaldehyde in amino-catalyzed mesoporous silica nanoparticles (MSN) has revealed varying catalytic activity with the size of the pores of MSN. The pore size dependence related to the reactivity indicates that the diffusion process is important. A detailed molecular-level analysis for understanding diffusion requires assessment of the noncovalent interactions of the molecular species involved in the aldol reaction with each other, with the solvent, and with key functional groups on the pore surface. Such an analysis is presented here based upon the effective fragment potential (EFP). The EFP method can calculate the intermolecular interactions, decomposed into Coulomb, polarization, dispersion, exchange-repulsion, and charge-transfer interactions. In this study, the potential energy surfaces corresponding to each intermolecular interaction are analyzed for homo- and hetero-dimers with various configurations. The monomers that compose dimers are five molecules such as p-nitrobenzaldehyde, acetone, n-hexane, propylamine, and silanol. The results illustrate that the dispersion interaction is crucial in most dimers.A solvent-free procedure for the formation of amides without exclusion of air and moisture is described. Using tetramethoxysilane 1, hexamethoxydisilane 2 and dodecamethoxy-neopentasilane 3 as coupling agent carboxylic acids and amines are reacted to form amides in good to excellent yields. The formation of these amides was confirmed by NMR spectroscopy and mass spectrometry. Remarkably, neopentasilane 3 exceeds the performance of the currently used monosilanes as coupling agent in terms of group tolerance and yield.2,2'-Bipyridine based bisphosphine [C5H3NN(H)CH2PPh2]2 (1) and its bischalcogenide derivatives [C5H3NN(H)CH2P(E)Ph2]2 (2, E = O; 3, E = S; 4, E = Se) were synthesized, and further reacted with BF3·Et2O/Et3N to form doubly B ← N fused compounds [C5H3N(BF2)NCH2P(E)Ph2]2 (5, E = O; 6, E = S; 7, E = Se) in excellent yields. The influence of the PE bonds on the electronic properties of the doubly B ← N fused systems and their structural features were investigated in detail, supported by extensive experimental and computational studies. Compound 6 exhibited a very high quantum yield of ϕ = 0.56 in CH2Cl2, whereas compound 7 showed a least quantum yield of ϕ = 0.003 in acetonitrile. Density functional theory (DFT) calculations demonstrated that the LUMO/HOMO of compounds 5-7 mostly delocalized over the entire π-conjugated frameworks. The involvement of PE bonds in the HOMO energy level of these compounds follows the order PO less then PS less then PSe. Time-correlated single photon counting (TCSPC) experiments of compounds 5-7 revealed the singlet lifetime of 4.26 ns for 6, followed by 4.03 ns for 5 and a lowest value of 2.18 ns (τ1) and 0.47 ns (τ2) with a double decay profile for 7. Our findings provide important strategies for the design of highly effective B ← N bridged compounds and tuning their photophysical properties by oxidizing phosphorus with different chalcogens. Compounds 5 and 6 have been employed as green emitters (λem = 515 nm) in fluorescent organic light-emitting diodes (OLEDs). For compound 5, doped into the poly(9-vinylcarbazole) (PVK) matrix with 5 wt% doping concentration, nearly 90 Cd m-2 luminance with 0.022% external quantum efficiency (EQE) was achieved. The best performance was observed for compound 6 doped into PVK by 1 wt% having a maximum luminance of 350 Cd m-2 and a similar EQE value.A single-atom alloy (SAA) consisting of an abundant metal host and a precious metal guest is a promising catalyst to reduce the cost without a loss of activity. DFT calculations of Ni- and Cu-based alloys nX/M(111) (X = Cu, Ag, or Au for M = Ni; X = Ni, Pd, or Pt for M = Cu; n = 1-4) reveal that a phase-separated alloy (PSA) is produced by Cu atoms with Ni(111) but an SAA is produced by Au atoms with Ni(111) and Pd and Pt atoms with Cu(111). In the Ni(111)-based Ag alloy and Cu(111)-based Ni alloy, the relative stabilities of the SAA and PSA depend on coverages of Ag on Ni(111) and Ni on Cu(111). The interaction energy (Eint) between the Xn cluster and M(111) host is larger than that between one X atom and the M(111) host, because the Xn cluster forms more bonding interactions with the M(111) host than does one X atom. When going from one X atom to the X4 cluster, the Eint values of Au and Pt clusters respectively with Ni(111) and Cu(111) increase to a lesser extent than those of Cu and Ni clusters respectively with Ni(111) and Cu(111). Consequently, Au and Pt atoms tend to form SAAs respectively with Ni(111) and Cu(111) hosts compared to Cu and Ni atoms. This trend in the Eint value is determined by the valence orbital energies of the X atom and the Xn cluster. Cu atoms in nCu/Ni(111) have a slightly positive charge but Ag atoms in nAg/Ni(111), Au atoms in nAu/Ni(111), and Ni, Pd, and Pt atoms in nX/Cu(111) (X = Ni, Pd, or Pt) have a negative charge. The negative charge increases in the order Ag nPt/Cu(111). These properties are explained based on the electronic structures.The hydrogen bond network has a major role in determining the physical and chemical properties of water both in the solid and in the liquid state. In the bulk liquid phase, there is a coexistence of water molecules with different degrees of coordination and their relative amount changes according to the conditions (e.g., temperature, presence of solutes). Ice shows a larger amount of topologically under-coordinated water molecules at the surface as compared to the bulk. Snow is composed of many ice crystallites, and it differs from bulk ice because of the much larger specific surface area. The OH-stretching band is the most intense signal of the Raman spectrum of water, and it gives direct insight about the hydrogen bond network. In this work we compared the OH-stretching region of the Raman spectra of water, ice and snow acquired with excitations in the visible (532 nm) and in the UV-C range (250-200 nm) by exploiting the tunability of the synchrotron radiation. By moving towards the highest energy excitation we observed in liquid water a monotonic increase of the relative intensities of the peaks associated with weakly hydrogen-bonded water molecules. With visible excitation, the Raman spectrum of snow displays a larger contribution from weakly hydrogen-bonded water molecules at the surfaces when compared to the spectrum of bulk ice. By using excitation sources in the UV-C range, we observe a further enhancement of the contribution of the surfaces in the spectra of snow. By considering the reported changes of the water absorption coefficient in relation to the hydrogen bonding environment, we interpreted our results as a preferential pre-resonance excitation of weakly hydrogen-bonded water molecules induced by the UV-C sources.The rapid development of applications relying on magnetism at the nanoscale has put a spotlight on nanoparticles with novel morphologies that are associated with enhanced electronic and magnetic properties. In this quest, nanoalloys combining highly magnetic cobalt and weakly reactive gold could offer many application-specific advantages, such as strong magnetic anisotropy. In the present study, we have employed density functional theory (DFT) calculations to provide a systematic overview of the size- and morphology-dependence of the energetic order and magnetic properties of AuCo nanoparticles up to 2.5 nm in diameter. The core-shell icosahedron was captured as the most favourable morphology, showing a small preference over the core-shell decahedron. However, the magnetic properties (total magnetic moments and magnetic anisotropy) were found to be significantly improved within the L10 ordered structures, even in comparison to monometallic Co nanoparticles. Atom-resolved charges and orbital moments accessed through the DFT analysis of the electronic level properties permitted insight into the close interrelation between the AuCo nanoparticle morphology and their magnetism. These results are expected to assist in the design of tailored magnetic AuCo nanoalloys for specific applications.Herein we report double-shell Na@Sn6L6@Sn3L3 clusters and their further assembly into a 2D layer, which belongs to a rare Sn-oxo coordination cage-based extended structure. Tetrahedral citrate ligands with multiple coordination sites play key roles in such hierarchical assembly.Titanium dioxide (TiO2) has attracted enormous interest in abundant photocatalytic reactions, but its photocatalytic efficiency is limited by its wide bandgap and the rapid recombination of electron-hole pairs. To overcome the disadvantages of its rapid electron-hole recombination rate, herein, oxidative TiO2 was one-step fabricated using potassium permanganate (KMnO4), exhibiting improved charge separation efficiency and photocatalytic degradation performance towards methyl orange (MO). Remarkably, the first-order photodegradation rate of oxidative TiO2 is 3.68 times higher than that of pristine TiO2 under the irradiation of simulated sunlight and 2.15 times higher under ultraviolet light. This exceptional photocatalytic activity is attributed to the additional oxygen doped into the interstices of the TiO2 lattice, creating impurity states in the bandgap acting as trapping sites, thus facilitating charge separation. This work provides a promising strategy for the insertion of O atoms into the TiO2 lattice and expands the photocatalytic application of the related materials.
