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991.
Shengjian Zhao Shaohua Qin Zhanlin Jia Shuai Fu Peigang He Xiaoming Duan Zhihua Yang Daxin Li Dechang Jia Jie Zhang Yu Zhou 《Journal of the American Ceramic Society》2020,103(9):4957-4968
In this paper, monoclinic SrAl2Si2O8 ceramics with porous structures were prepared based on ion-exchanged geopolymer precursor technique. Micron-level pores with a homogeneous pore-size distribution were introduced into the inorganic framework using foaming agents. The results demonstrated that the apparent density, pore-size distribution and specific surface area of porous geopolymer precursors can be well-engineered via tailoring the category and concentration of the foaming agent. After being treated at 900°C, hexagonal SrAl2Si2O8 first-crystallized from the amorphous geopolymer matrix and then gradually converted into monoclinic SrAl2Si2O8 between 1100°C and 1200°C. The resulting monoclinic SrAl2Si2O8 ceramics maintained the porous structures during high-temperature treatments and exhibited high porosity, specific surface area, and compressive strength. The aforementioned strategy not only achieves monoclinic SrAl2Si2O8 ceramics with well-defined and robust microstructures, but also provides an alternative route to prepare other porous ceramics, with potential applications in fields of high-temperature filters, adsorbents, and heterogeneous catalysis. 相似文献
992.
Puxian Xiong Chibin Zheng Mingying Peng Zhihao Zhou Feifei Xu Kexin Qin Yiyu Hong Zhijun Ma 《Journal of the American Ceramic Society》2020,103(12):6922-6931
Till now, many doped persistent luminescence (PersL) phosphors have been investigated and found various applications in such as bioimaging, photocatalysis and information storage, but introducing PersL emitters into a proper host is mostly complex. In this research, a self-activated PersL phosphor Ba2Zr2Si3O12 (BZSO) is prepared by solid state reaction. By adding NH4Cl, the self-activated PersL intensity is evidently enhanced. The trap depths and concentrations are examined by thermoluminescence spectra. Meanwhile, Bi3+ ions are introduced into BZSO and show wide band photoluminescence (PL) from 300 to 600 nm. Moreover, the PL of Bi3+ is tunable under excitation by 265-350 nm lights. Furthermore, as a proof-of-concept design, we designed a patterned quick response (QR) code based on the self-activated PersL of BZSO, and the information of “South China University of Technology (SCUT)” can be read out by the code scanning technology. Bi3+-doped BZSO phosphors are suggested to provide potential applications in information storage by its self-activated PersL, and to excite researchers to study the tunable PL in Bi3+-doped phosphor. 相似文献
993.
Xiao-Fang Song Jiang-Tao Qin Ting-Ting Li Guo Liu Xiang-Xiang Xia Yue-Sheng Li Yi Liu 《应用聚合物科学杂志》2020,137(13):48516
Enriched selective adsorption-photocatalytic activity of Poly (vinyl alcohol)/Polyaniline/TiO2 (PVA/PANI/TiO2, noted as PAT) recyclable hydrogel photocatalyst with 3D structures were prepared by self-assembling and electron beam radiation crosslingking method. TiO2 nanoparticles were successfully introduced into the 3D matrix of the PVA/PANI hydrogel and manifested by FTIR, TG, XRD, XPS, and SEM-EDS. The microstructure of PAT was characterized further by SEM, TEM, and BET. The highly selective adsorption-photocatalytic activity of PAT was tested by the degradation of cationic or anionic dye and reduction of heavy metal ion in a closed and flow system under UV light irradiation. The results showed that PAT had a highest selective adsorption-photocatalytic performance at the appropriate content of PVA (10 wt %), TiO2 (15 wt %) and suitable radiation dose (50 kGy), which could be attributed to the synergistic effect of excellent selective adsorption and effective photocatalytic degradation. The mechanism of selective adsorption-photocatalytic on PAT was revealed synchronously in this study. Particularly, the novel PAT photocatalyst with 3D network structure also affords ease of separation and recycling, which is beneficial to water purification in a flow system. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48516. 相似文献
994.
In order to explore the effects of chlorine and fluorine on photophysical properties and the differences, in this work, we synthesized five new polymers, P1 – P5 , in which benzo[1,2-b:4,5-b]dithiophene as the electron donating and benzothiadiazole as electron withdrawing. Analysis of these five polymers showed that the introduction of Cl and F atoms can deeper the highest occupied molecular orbital of these polymers and enhance the absorption of light by the species, thereby improving Voc and Jsc. Chlorination has a stronger ability to reduce energy levels and broaden the absorption spectrum compared to fluorination. Among them, P2 showed an efficiency of 4.08% with Jsc of 11.28 mA/cm2, Voc of 0.79 V, and fill factor (FF) of 0.45. Since chlorination is easier than fluorination in terms of synthesis, it is advantageous for practical applications. Therefore, we think that chlorination should not be ignored when designing high efficiency photovoltaic materials, especially when their fluorinated counterparts have proven to have good properties. 相似文献
995.
Xiatong Qin Weihao Liu Genqi Liu Chenrui Ren Chenhui Liu Huanhuan Li Yunlei Cao 《应用聚合物科学杂志》2020,137(42):49299
A novel molecularly imprinted two-dimensional (2-D) photonic crystal hydrogels (MIPH) for sensitive and label-free recognition of 2,4-dichlorophenol (2,4-DCP) was prepared. The 2-D photonic crystal template was fabricated by using air-water interface self-assembly method. And then the template was embedded with molecularly imprinted polymer, which was synthesized with 2,4-DCP as imprinted molecules, dimethyl sulfoxide as solvent, acrylic acid and acrylamide as functional monomers, N,N-methylene bis acrylamide as cross-linker, azobisisobutyronitrile as initiator. The imprinted molecules were removed by 0.01 M ammonia solution. The results indicated that the 2,4-DCP molecularly imprinted 2-D photonic crystal hydrogels has good response and recognition ability to 2,4-DCP. When the molar ratio of cross-linking density of MIPH is 2.3% and the molar ratio of imprinting molecule is 5.0%, the change of Debye ring diameter is the largest. The diameter of Debye ring increased by 7.1 mm when the concentration of 2,4-DCP changed from 0 to 1 × 10−6 M, and the particle spacing of MIPH reduced 38 nm. In addition, the diameter of the Debye ring hardly changed in the solution of analogues of 2,4-DCP such as, phenol, 2-chlorophenol, 2,4,6-trichlorophenol and so on, indicating that the MIPH has highly sensitivity and specificity. 相似文献
996.
Zhanbin Wang Jiahao Liu Houchao Shan Guozhen Li Ze Wang Zhihao Si Di Cai Peiyong Qin 《应用聚合物科学杂志》2020,137(42):49308
In this study, Schiff base network (SNW)-1 nanoparticles with high hydrophilicity and large specific surface area were used to prepare polyvinyl alcohol (PVA)-based mixed matrix membranes (MMMs), which were evaluated for ethanol dehydration. Because of the low difference of density between SNW-1 and PVA, the as-prepared nanoparticles can be uniformly distributed into the PVA active layer. The effects of SNW-1 loading, feed temperature, and water concentration on pervaporation (PV) performance were further studied. The results showed the MMM with 10 wt% of SNW-1 loading exhibited a separation factor of 1,501 and a permeation flux of 187 g m−2 h−1 for feeding 95 wt% ethanol/water binary solution at 75°C. Overall, the SNW-1/PVA MMMs showed great prospect in ethanol dehydration via PV. 相似文献
997.
Xing Qin Prof. Yongsheng Li 《Chembiochem : a European journal of chemical biology》2020,21(9):1236-1253
The emergence and development of nanomedicine have alleviated problems existing in traditional chemotherapy drugs, such as short lifetime, concomitant side effects, and weak tumor-targeting capability. Nevertheless, the further applications of drug-loaded nanocarriers are still limited by their premature leakage, weak targeting capability, and insufficient intracellular release. In past decades, various nanocarriers, including gold nanoparticles, porous silica nanoparticles, carbon-based nanoparticles, micelles, liposomes, and polymer–drug conjugates, have been intensively investigated for tumor therapy. Among these, polymer-based nanocarriers have attracted more attention due to their biocompatibilities and capability of being modified for stimuli-responsive drug release. In this review, three popular strategies to design and synthesize polymer-based stimuli-responsive nanocarriers are discussed. The discussion goes from stimuli-responsive polymers with responsive backbones or modified by responsive functional groups for drug encapsulation and release to polymer–drug conjugates with responsive covalent linkages. In particular, due to the facile synthetic processes and mild reaction conditions for crosslinked structures, the latest progress in responsive crosslinked structures is emphasized. Finally, future perspectives for these nanomaterials are given, which are expected to provide inspiration for researchers to design more effective and safer tumor-killing nanomedicines. 相似文献
998.
Dr. Jiayao Y. Wang Dr. Jiaqi Q. Li Prof. Dr. Yumei M. Xiao Prof. Dr. Bin Fu Prof. Dr. Zhaohai H. Qin 《ChemMedChem》2020,15(5):404-410
Mitochondrial oxidative damage and dysfunction contribute to a wide range of human diseases. Considering the limitation of conventional antioxidants and that mitochondria are the main source of reactive oxygen species (ROS) which induce oxidative damage, mitochondria-targeted antioxidants which can selectively block mitochondrial oxidative damage and prevent various types of cell death have been widely developed. As a lipophilic cation, triphenylphosphonium (TPP) has been commonly used in designing mitochondria-targeted antioxidants. Conjugated with the TPP moiety, antioxidants can achieve more than 1000-fold higher mitochondrial concentration depending on cell membrane potentials and mitochondrial membrane potentials. Herein we discuss the deficiencies of conventional antioxidants and the advantages of mitochondrial targeting, and review various types of TPP-based mitochondria-targeted antioxidants. These provide theoretical and background support for the design of new anti-oxidant. 相似文献
999.
以白藜芦醇和2, 4-二硝基苯磺酰氯为原料,通过酯化法得到白藜芦醇磺酸酯,通过NMR和LC-MS确定了该化合物结构。以维生素C为阳性对照,研究白藜芦醇磺酸酯对2, 2-联苯基-1-苦基肼(DPPH)自由基和2, 2′-联氮-双-3-乙基苯并噻唑啉-6-磺酸(ABTS)自由基的清除活性和抗氧化活性;噻唑蓝(MTT)法研究其对人肺癌细胞A549的增殖活性。实验结果表明,目标产物收率为33.1%。同时,目标产物在浓度为1.0 mg/mL时,对DPPH自由基和ABTS自由基的清除率分别为31.6%和42.7%,抗氧化活性均高于白藜芦醇,但低于维生素C;目标产物对人肺癌细胞A549具有较好抑制作用,IC50值为(10.2±0.37)μg/mL。 相似文献
1000.