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951.
A multifunctional thiophene-based covalent triazine framework (TTPATTh) with triphenylamine as core is synthesized by Friedel–Crafts reaction of cyanuric chloride with thienyl derivative for the first time. The yield of TTPATTh (99.59%) is far higher than that of the carbazole-based CTF (TTPATCz, 47.03%). TTPATTh and TTPATCz possess high BET surface areas with 1235 and 2501 m2 g–1 as well as high pore volumes with 1.60 and 2.23 cm3 g–1, respectively. TTPATTh and TTPATCz have high thermal stability with high thermal decomposition temperatures of 514 and 598 °C in nitrogen atmosphere. With the introduction of triazine rings, the fluorescence sensing sensitivities of TTPATTh and TTPATCz to picric acid and iodine are improved significantly. Especially for TTPATTh, the Ksv values reach 5.95 × 105 and 1.61 × 104 L mol–1, and LODs reach 1.02 × 10–12 and 1.86 × 10–12 mol L–1. To the best of the knowledge, this is the most sensitive value among thiophene-based porous organic polymers to PA and I2. Furthermore, TTPATTh and TTPATCz can also adsorb iodine in vapor phase, cyclohexane solution and aqueous solution, and release iodine by heating or in ethanol solution. The efficiency of controlling the release of iodine is higher than that in ethanol. 相似文献
952.
Xiaodong Zhang Dr. Ziqian Wang Zongwei Guo Dr. Ting Song Nianzhe He Junjie Zhu Keke Cao Prof. Zhichao Zhang 《Chembiochem : a European journal of chemical biology》2021,22(2):326-329
Bcl-2 and Mcl-1, the two arms of the anti-apoptotic Bcl-2 family proteins, have been identified as key regulators of apoptosis and effective therapeutic targets of cancer. However, no small-molecular probe is capable of profiling and visualizing both Bcl-2 and Mcl-1 simultaneously in situ. Herein, we report a multifunctional molecular probe (BnN3-OPD-Alk) by a “three-in-one” molecular designing strategy, which integrated the Bcl-2/Mcl-1 binding ligand, fluorescent reporter group and photoreactive group azido into the same scaffold. BnN3-OPD-Alk exhibited sub-micromolar affinities to Bcl-2/Mcl-1 and bright green self-fluorescence. It was then successfully applied for Bcl-2/Mcl-1 labeling, capturing, enriching, and bioimaging both in vitro and in cells. This strategy could facilitate the precise early diagnosis and effective therapy of dual Bcl-2/Mcl-1-related diseases. 相似文献
953.
There is a growing demand to develop epoxy resins (EP) with smoke suppression as well as satisfactory flame retardancy. Herein, bio-based cobalt alginate is successfully fabricated and incorporated into EP to prepare EP/Cobalt Alginate composites with better fire safety performance. The addition of cobalt alginate reduces the thermal-decomposition rate, temperature at maximum weight-loss rate of EP, whereas obviously improves the thermal stabilities at a higher temperature range. Furthermore, the addition of cobalt alginate substantially reduces the fire hazard of EP, resulting in 56.2% reduction in peak heat release rate, as well as 17.8% and 56.3% reduction in total smoke production and peak smoke production rate, respectively, compared with EP matrix. Moreover, the presence of cobalt alginate increases smoke-suppressant properties, according to the smoke density test. Additionally, the incorporation of cobalt alginate has no obviously destructive effect on the mechanical properties of EP, while EP/Cobalt Alginate-3 exhibits a 27.0% improvement in impact strength. In prospective, this study may provide a significant method for producing eco-friendly flame retardant EP. 相似文献
954.
Shu Yan Fanyong Zhang Xue Feng Jian Kong Bo Wang Jinlong Yang 《International Journal of Applied Ceramic Technology》2021,18(3):817-829
A hierarchical porous cenosphere/geopolymer composite foam (FHCs/KGP) was fabricated by the simultaneous incorporation of O2 pore from hydrogen peroxide and cenosphere filler addition. Effects of both H2O2 content and high-temperature treatment on the microstructure, porosity and strength of porous FHCs/KGP foams were investigated systematically. The obtained FHCs/KGP foams showed typical amorphous structure and desirable porosity from 65 to 82%. The composites could crystallize in situ to FHCs/leucite foams above 1000℃. Compression strength of the FHCs/leucite foams showed a maximum value of 5 ± 0.3 MPa when treated at 1000°C. The improvement of mechanical properties for the composite foams was attributed to crack deflection, fractured microspheres and the good bond between the FHCs and matrix. This study could open opportunities to employ cellular foams as alternatives in structure and filtration applications. 相似文献
955.
Yang Zhu Xiangli Meng Qiang Zhang Liansheng Yan Hong Cui 《International Journal of Applied Ceramic Technology》2021,18(4):1330-1341
A 3D architecture carbon fiber preform, specifically fine-woven cloth and punctured felt preform, is used to manufacture a novel advanced Cf/C-SiC-ZrC composite. The composite matrix is produced by chemical vapor infiltration (CVI) plus precursor infiltration and pyrolysis (PIP) process and finalized by using a chemical vapor deposition (CVD) of SiC coating to make the final density of the material reach 1.95 g/cm3. The organic precursors of SiC and ZrC have a weight ratio of 4:1 in a xylene solute. The composite mechanical properties, such as tensile, compression, bending, shear, and Z-direction load bearing, are introduced under analysis to find possible applications for the composite. What is more, scanning electron microscope (SEM) images are employed to illustrate the failure behavior of the ceramic composite. The results showed that the punctured filament tows will be beneficial, not only for the composite to withstand compression force up to 308.6 MPa and shear strength to 18.14 MPa but also for the alternatively stacked weave piles and short fiber layers to support the punctured bundles, as well as to hold the composite structure under mechanical forces from different orientations, which is believed to reinforce the ceramic matrix for some high pressure and severe ablation applications. 相似文献
956.
Yuan Junjie Zhu Yao Wang Jizhang Liu Zhigang He Meiying Zhang Tao Li Pingping Qiu Fengxian 《Journal of Inorganic and Organometallic Polymers and Materials》2021,31(9):3867-3879
Journal of Inorganic and Organometallic Polymers and Materials - In recent decades, straw waste is the major byproduct around agriculture that has become one of the factors of environmental... 相似文献
957.
Sajjad Muhammad Asif Sana Ullah Guan Linlin Jiao Yangjing Jiang Yuhan Zhang Linlin Wen Jia Zhang Shuyu Lin Yuting Zhang Shuangshuang Ding Zhiwei Ren Yang Zhou Xiaowei Hu Wanbiao Liu Zhu 《Journal of Inorganic and Organometallic Polymers and Materials》2021,31(11):4440-4441
Journal of Inorganic and Organometallic Polymers and Materials - The original version of this article unfortunately contained mistakes. In line 9 of the abstract, 5% should read as 2%. The... 相似文献
958.
吉兰泰油田固阳组的巨厚砂砾岩储层地层矿化度较高,油水关系较为明显,但常规测井解释技术评价该套储层产能与试油结果差异较大,影响了该套储层的高效开发.针对这套储层厚度大、非均质强、孔隙结构复杂的特点,通过对核磁共振测井资料宏观尺度和微观尺度的分析,构建基于储层品质主控因素分析的储层综合指数,与试油、试采等动态资料相结合,建立储层基于产液能力的分级评价模型,实现储层分级评价.该方法提高了有效储层的识别精度,为油田分段开发方案的设计、提高油藏采收率、延长稳产时间,提供了可靠依据.将该方法应用于新井储层综合评价中,效果良好. 相似文献
959.
碳酸锂溶解度在工业结晶生产中是十分重要的基础数据。采用浸入式红外探头和拉曼探头在线监测溶液体系中CO32-和碳酸锂的特征峰峰强的变化,依据Lambert-Beer定律得出溶液体系中实时在线测定碳酸锂的溶解度。通过在线测定,测得碳酸锂在氯化钠-氯化钾溶液(cNaCl=0.446 6 mol/L,cKCl=0.015 8 mol/L)中的溶解度高于在水中的溶解度值。实验测试出的水中碳酸锂的溶解度数据还能与Van′t Hoff方程较好地关联,进一步测算碳酸锂在其他温度下水中的溶解度值。此外,该方法测定的碳酸锂在水中的溶解度数据比文献值中采用重量分析法测试出的溶解度数据偏小,是因为测试装置不同造成的。 相似文献
960.