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981.
Dr. Javeed Mahmood Seok‐Jin Kim Hyuk‐Jun Noh Dr. Sun‐Min Jung Ishfaq Ahmad Dr. Feng Li Jeong‐Min Seo Prof. Jong‐Beom Baek 《Angewandte Chemie (International ed. in English)》2018,57(13):3415-3420
A three‐dimensional (3D) cage‐like organic network (3D‐CON) structure synthesized by the straightforward condensation of building blocks designed with gas adsorption properties is presented. The 3D‐CON can be prepared using an easy but powerful route, which is essential for commercial scale‐up. The resulting fused aromatic 3D‐CON exhibited a high Brunauer–Emmett–Teller (BET) specific surface area of up to 2247 m2 g?1. More importantly, the 3D‐CON displayed outstanding low pressure hydrogen (H2, 2.64 wt %, 1.0 bar and 77 K), methane (CH4, 2.4 wt %, 1.0 bar and 273 K), and carbon dioxide (CO2, 26.7 wt %, 1.0 bar and 273 K) uptake with a high isosteric heat of adsorption (H2, 8.10 kJ mol?1; CH4, 18.72 kJ mol?1; CO2, 31.87 kJ mol?1). These values are among the best reported for organic networks with high thermal stability (ca. 600 °C). 相似文献
982.
Dr. Qi Liu Dr. Zhilei Ge Dr. Xiuhai Mao Dr. Guobao Zhou Prof. Xiaolei Zuo Dr. Juwen Shen Dr. Jiye Shi Prof. Jiang Li Prof. Lihua Wang Prof. Xiaoqing Chen Prof. Chunhai Fan 《Angewandte Chemie (International ed. in English)》2018,57(24):7131-7135
Weak ligand–receptor recognition events are often amplified by recruiting multiple regulatory biomolecules to the action site in biological systems. However, signal amplification in in vitro biomimetic systems generally lack the spatiotemporal regulation in vivo. Herein we report a framework nucleic acid (FNA)‐programmed strategy to develop valence‐controlled signal amplifiers with high modularity for ultrasensitive biosensing. We demonstrated that the FNA‐programmed signal amplifiers could recruit nucleic acids, proteins, and inorganic nanoparticles in a stoichiometric manner. The valence‐controlled signal amplifier enhanced the quantification ability of electrochemical biosensors, and enabled ultrasensitive detection of tumor‐relevant circulating free DNA (cfDNA) with sensitivity enhancement of 3–5 orders of magnitude and improved dynamic range. 相似文献
983.
Qiuwei Shi Yiren Zhong Min Wu Prof. Hongzhi Wang Prof. Hailiang Wang 《Angewandte Chemie (International ed. in English)》2018,57(29):9069-9072
Developing Na metal anodes that can be deeply cycled with high efficiency for a long time is a prerequisite for rechargeable Na metal batteries to be practically useful despite their notable advantages in theoretical energy density and potential low cost. Their high chemical reactivity with the electrolyte and tendency for dendrite formation are two major issues limiting the reversibility of Na metal electrodes. In this work, we introduce for the first time potassium bis(trifluoromethylsulfonyl)imide (KTFSI) as a bifunctional electrolyte additive to stabilize Na metal electrodes, in which the TFSI? anions decompose into lithium nitride and oxynitrides to render a desirable solid electrolyte interphase layer while the K+ cations preferentially adsorb onto Na protrusions and provide electrostatic shielding to suppress dendritic deposition. Through the cooperation of the cations and anions, we have realized Na metal electrodes that can be deeply cycled at a capacity of 10 mAh cm?2 for hundreds of hours. 相似文献
984.
Rational Fabrication of Anti‐Freezing,Non‐Drying Tough Organohydrogels by One‐Pot Solvent Displacement 下载免费PDF全文
Fan Chen Dan Zhou Jiahui Wang Tianzhen Li Prof. Dr. Xiaohu Zhou Dr. Tiansheng Gan Dr. Stephan Handschuh‐Wang Prof. Dr. Xuechang Zhou 《Angewandte Chemie (International ed. in English)》2018,57(22):6568-6571
Tough hydrogels, polymeric network structures with excellent mechanical properties (such as high stretchability and toughness), are emerging soft materials. Despite their remarkably mechanical features, tough hydrogels exhibit two flaws (freezing around the icing temperatures of water and drying under arid conditions). Inspired by cryoprotectants (CPAs) used in the inhibition of the icing of water in biological samples, a versatile and straightforward method is reported to fabricate extreme anti‐freezing, non‐drying CPA‐based organohydrogels with long‐term stability by partially displacing water molecules within the pre‐fabricated hydrogels. CPA‐based Ca‐alginate/polyacrylamide (PAAm) tough hydrogels were successfully fabricated with glycerol, glycol, and sorbitol. The CPA‐based organohydrogels remain unfrozen and mechanically flexible even up to ?70 °C and are stable under ambient conditions or even vacuum. 相似文献
985.
Dr. Wonhee Lee Young Eun Kim Dr. Min Hye Youn Dr. Soon Kwan Jeong Dr. Ki Tae Park 《Angewandte Chemie (International ed. in English)》2018,57(23):6883-6887
Electrochemical reduction of carbon dioxide (CO2) into value‐added chemicals is a promising strategy to reduce CO2 emission and mitigate climate change. One of the most serious problems in electrocatalytic CO2 reduction (CO2R) is the low solubility of CO2 in an aqueous electrolyte, which significantly limits the cathodic reaction rate. This paper proposes a facile method of catholyte‐free electrocatalytic CO2 reduction to avoid the solubility limitation using commercial tin nanoparticles as a cathode catalyst. Interestingly, as the reaction temperature rises from 303 K to 363 K, the partial current density (PCD) of formate improves more than two times with 52.9 mA cm?2, despite the decrease in CO2 solubility. Furthermore, a significantly high formate concentration of 41.5 g L?1 is obtained as a one‐path product at 343 K with high PCD (51.7 mA cm?2) and high Faradaic efficiency (93.3 %) via continuous operation in a full flow cell at a low cell voltage of 2.2 V. 相似文献
986.
Dr. Xiulin Fan Dr. Fei Wang Dr. Xiao Ji Ruixing Wang Dr. Tao Gao Singyuk Hou Dr. Ji Chen Tao Deng Dr. Xiaogang Li Dr. Long Chen Dr. Chao Luo Luning Wang Prof. Chunsheng Wang 《Angewandte Chemie (International ed. in English)》2018,57(24):7146-7150
Low‐cost multivalent battery chemistries (Mg2+, Al3+) have been extensively investigated for large‐scale energy storage applications. However, their commercialization is plagued by the poor power density and cycle life of cathodes. A universal polyimides@CNT (PI@CNT) cathode is now presented that can reversibly store various cations with different valences (Li+, Mg2+, Al3+) at an extremely fast rate. The ion‐coordination charge storage mechanism of PI@CNT is systemically investigated. Full cells using PI@CNT cathodes and corresponding metal anodes exhibit long cycle life (>10000 cycles), fast kinetics (>20 C), and wide operating temperature range (?40 to 50 °C), making the low‐cost industrial polyimides universal cathodes for different multivalent metal batteries. The stable ion‐coordinated mechanism opens a new foundation for the development of high‐energy and high‐power multivalent batteries. 相似文献
987.
高效液相色谱-串联质谱法测定黄瓜与土壤中烯酰吗啉和氰霜唑及其代谢物的残留量 总被引:1,自引:0,他引:1
为评价烯酰吗啉和氰霜唑在黄瓜和土壤中的安全性,建立了同时检测烯酰吗啉和氰霜唑及其代谢物4-氯-5-(4-甲苯基)-1H-咪唑-2-腈(CCIM)的高效液相色谱-串联质谱法。样品经乙腈提取,乙二胺-N-丙基硅烷键合相(PSA)和十八烷基硅烷键合相(C18)净化后,质谱多反应监测模式扫描,基质匹配标准曲线外标法定量。烯酰吗啉、氰霜唑和CCIM在0. 01~0. 5 mg/L范围内均具有良好的线性关系,相关系数(r)均大于0. 994 0,在0. 05、0. 1、0. 5 mg/kg加标浓度下,3种待测物在黄瓜和土壤中的平均回收率为78%~105%,相对标准偏差(RSD)为1. 3%~14. 8%,定量下限为0. 05 mg/kg。对35%氰霜唑·烯酰吗啉悬浮剂在黄瓜和土壤中的残留动态及最终残留量进行分析,发现烯酰吗啉、氰霜唑及CCIM之和在黄瓜和土壤中消解较快,烯酰吗啉在黄瓜和土壤中的半衰期分别为1. 2~2. 1、3. 0~9. 6 d;氰霜唑及CCIM之和在黄瓜和土壤中的半衰期为0. 9~2. 3、1. 8~6. 2 d。该方法简单、快速、灵敏度及准确度高,能够满足黄瓜和土壤中烯酰吗啉、氰霜唑及CCIM残留量的检测要求。 相似文献
988.
采用生物矿化策略,在磷酸盐缓冲液中制备了猪肝酯酶(Porcine liver esterase,PLE)杂化"纳米花"(Ca3(PO4)2-PLE)。利用扫描电镜、元素能谱分析及红外光谱对所制备的杂化"纳米花"进行了形貌和成分分析。对杂化"纳米花"制备过程中的参数进行优化,结果表明:在10 mmol/L磷酸盐缓冲液(p H 7. 4)中,猪肝酯酶质量浓度为0. 3 g/L,钙离子浓度为500 mmol/L,制备温度为20℃时,所制备的Ca3(PO4)2-PLE具有最高酶活,其酶活为同等酶浓度下液酶酶活的169%。将制备的Ca3(PO4)2-PLE用于4种菊酯类农药的酶解性能研究,发现相同条件下,Ca3(PO4)2-PLE的酶解率均优于液酶。此外,制备的Ca3(PO4)2-PLE用于菊酯农药酶解循环2次后仍保持70%以上的活力。 相似文献
989.
990.
光催化具有无污染、安全高效等优点,已成为环保领域的研究热点。 本文选择2,4-二(3,5-二甲基吡唑)-6-二乙基胺-1,3,5-三嗪(L1)和2, 6-二[3-(5-甲基吡唑基)]吡啶(L2)为配体、以RuCl3为金属源,合成了3种配合物[Ru(L1)Cl3](1)、[Ru(L2)2]·Cl3(2)和[Ru(L2)2]·(H2BTC)·(HBTC)·H2O(3),同时进行了IR、UV-Vis、TG及X射线衍射等表征,并对配合物在光催化降解罗丹明B方面进行了探讨,结果表明,配合物13均具有一定程度的光降解效果,降解效果分别为46.8%、44.7%和40.4%。 相同条件下,加入H2O2后的配合物13的降解效果比金属盐、配体及H2O2单独存在时的降解效果好。 相似文献