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131.
A chiral catalyst, Cp*RhTsDPEN (Cp* = pentamethyl cyclopentadiene, TsDPEN = substitutive phenylsulfonyl-l,2-diphenylethylenediamine), was synthesized and immobilized at the surface of glass. The immobilized catalyst exhibited good catalytic efficiency for asymmetric transfer hydrogenation of aromatic ketones in water with HCOONa as hydrogen source.  相似文献   
132.
Ordered porous cabon with a 2-D hexagonal structure,high specific surface area and large pore volume was synthesized through a twostep heating method using tri-block copolymer as template and phenolic resin as carbon precursor.The results indicated the electrochemical performance of the sulfur/carbon composites prepared with the ordered porous carbon was significantly affected by the pore structure of the carbon.Both the specific capacity and cycling stability of the sulfur/carbon composites were improved using the bimodal micro/meso-porous carbon frameworks with high surface area.Its initial discharge capacity can be as high as 1200 mAh·g~(-1) at a current density of 167.5 mA·g~(-1)The improved capacity retention was obtained during the cell cycling as well.  相似文献   
133.
丁建勋  常非  王金成 《高分子科学》2014,32(12):1590-1601
Poly(lactide-co-glycolide)-poly(ethylene glycol)-poly(lactide-co-glycolide)(PLGA-PEG-PLGA) triblock copolymer was synthesized through the ring-opening polymerization of LA and GA with PEG as macroinitiator and stannous octoate as catalyst. The amphiphilic copolymer self-assembled into micelles in aqueous solutions, and formed hydrogels as the increase of temperature at relatively high concentrations(〉 15 wt%). The favorable degradability of the hydrogel was confirmed by in vitro and in vivo degradation experiments. The good cellular and tissular compatibilities of the thermogel were demonstrated. The excellent adhesion and proliferation of bone marrow mesenchymal stem cells endowed PLGA-PEGPLGA thermogelling hydrogel with fascinating prospect for cartilage tissue engineering.  相似文献   
134.
程博闻 《高分子科学》2014,32(6):786-792
A new strategy was developed to fabricate superhydrophobic nylon 6 nanofibers, in which the blend solutions of poly(dimethylsiloxane)(PDMS) prepolymer and nylon 6 was spun using an innovative solution blowing process, and then the PDMS prepolymer contianning nanofibers were cured to obtain PDMS/nylon 6 nanofiber mats. Morphology, surface composition, non-wetting property and protective performance were investigated. The results showed that the addition of PDMS prepolymer improved the spinnability of the spinning solutions, and the PDMS/nylon 6 nanofibers had smooth surfaces and diameters from 100 nm to 350 nm. The presence of PDMS effectively enhanced the hydrophobicity of the nanofiber mats, showing water contact angles of 132° to 161° for PDMS contents of 1 wt% to 3 wt%. The PDMS/nylon 6 mats also possessed excellent protective and transport properties. The results indicated the potential application of the novel nanofiber mats in protective clothing.  相似文献   
135.
The enzymatic hydrolysis of the native and the pretreated palm pressed fiber (PPF) was deeply investigated by using the enzyme cocktail ACCELLERASE 1500. Together with the spent PPF from the first hydrolysis and the further doubly-treated PPF, the proportions of three main components were determined and analyzed based on a triangle figure. The proportion (cellulose/hemicelluloses/lignin) in the spent PPF was equal to 44:23:33 and the surface morphology of the spent PPF looks very similar to the native PPF surface showing poor hydrolysis efficiency. After further double treatment, the proportion was changed evidently from the original 44:23:33 to 54:21:25 and the surface structure was significantly disrupted showing a potential to be hydrolyzed completely. Additionally, all samples were characterized by Fourier transform infrared spectroscopy and X-ray diffractogram through considerations of alkaline solution treatment, so as to understand better the nature of biomass hydrolysis, from the aspect of three biomass components.  相似文献   
136.
The oxygen vacancies of defective iron–cobalt oxide (FeCoOx-Vo) nanosheets are modified by the homogeneously distributed sulfur (S) atoms. S atoms can not only effectively stabilize oxygen vacancies (Vo), but also form the Co−S coordination with Co active site in the Vo, which can modulate the electronic structure of the active site, enabling FeCoOx-Vo-S to exhibit much superior OER activity. FeCoOx-Vo-S exhibits a mass activity of 2440.0 A g−1 at 1.5 V vs. RHE in 1.0 m KOH, 25.4 times higher than that of RuO2. The Tafel slope is as low as 21.0 mV dec−1, indicative of its excellent charge transfer rate. When FeCoOx-Vo-S (anode catalyst) is paired with the defective CoP3/Ni2P (cathode catalyst) for overall water splitting, current densities of as high as 249.0 mA cm−2 and 406.0 mA cm−2 at a cell voltage of 2.0 V and 2.3 V, respectively, can be achieved.  相似文献   
137.
The capability to significantly shorten the synthetic period of a broad spectrum of open organic materials presents an enticing prospect for materials processing and applications. Herein we discovered 1,2,4-triazolium poly(ionic liquid)s (PILs) could serve as a universal additive to accelerate by at least one order of magnitude the growth rate of representative imine-linked crystalline open organics, including organic cages, covalent organic frameworks (COFs), and macrocycles. This phenomenon results from the active C5-protons in poly(1,2,4-triazolium)s that catalyze the formation of imine bonds, and the simultaneous salting-out effect (induced precipitation by decreasing solubility) that PILs exert on these crystallizing species.  相似文献   
138.
This article offers a materials-chemistry perspective for colloidal quantum dots (QDs) in the field of display, including QD-enhanced liquid-crystal-display (QD-LCD) and QD-based light-emitting-diodes (QLEDs) display. The rapid successes of QDs for display in the past five years are not accidental but have a deep root in both maturity of their synthetic chemistry and their unique chemical, optical, and optoelectronic properties. This article intends to discuss the natural match of QD emitters for display and chemical means to eventually bring about their full potential.  相似文献   
139.
A non-conjugated polymer acceptor PF1-TS4 was firstly synthesized by embedding a thioalkyl segment in the mainchain, which shows excellent photophysical properties on par with a fully conjugated polymer, with a low optical band gap of 1.58 eV and a high absorption coefficient >105 cm−1, a high LUMO level of −3.89 eV, and suitable crystallinity. Matched with the polymer donor PM6, the PF1-TS4-based all-PSC achieved a power conversion efficiency (PCE) of 8.63 %, which is ≈45 % higher than that of a device based on the small molecule acceptor counterpart IDIC16. Moreover, the PF1-TS4-based all-PSC has good thermal stability with ≈70 % of its initial PCE retained after being stored at 85 °C for 180 h, while the IDIC16-based device only retained ≈50 % of its initial PCE when stored at 85 °C for only 18 h. Our work provides a new strategy to develop efficient polymer acceptor materials by linkage of conjugated units with non-conjugated thioalkyl segments.  相似文献   
140.
The use of gold nanoparticles as radiosensitizers is an effective way to boost the killing efficacy of radiotherapy while drastically limiting the received dose and reducing the possible damage to normal tissues. Herein, we designed aggregation-induced emission gold clustoluminogens (AIE-Au) to achieve efficient low-dose X-ray-induced photodynamic therapy (X-PDT) with negligible side effects. The aggregates of glutathione-protected gold clusters (GCs) assembled through a cationic polymer enhanced the X-ray-excited luminescence by 5.2-fold. Under low-dose X-ray irradiation, AIE-Au strongly absorbed X-rays and efficiently generated hydroxyl radicals, which enhanced the radiotherapy effect. Additionally, X-ray-induced luminescence excited the conjugated photosensitizers, resulting in a PDT effect. The in vitro and in vivo experiments demonstrated that AIE-Au effectively triggered the generation of reactive oxygen species with an order-of-magnitude reduction in the X-ray dose, enabling highly effective cancer treatment.  相似文献   
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