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991.
992.
993.
亚微米级Ag2S空心球的乳液法合成 总被引:4,自引:0,他引:4
Hollow Ag2S spheres have been prepared via hydrolyze reaction of Ag2S2O3, which formed from the reaction of AgNO3 with Na2S2O3, in cyclohexane/water/polyglycol emulsion system. It was found that the component of the reaction system has a significant influence on the formation of hollow Ag2S spheres. The possible formation mech-anism of the hollow Ag2S spheres in the emusion system was also discussed. 相似文献
994.
以小苏打溶液替代氢氧化钠和碳酸钠溶液作为隐形墨水,天然色素酒精浸取液为显色剂,以白醋替代盐酸作为消色剂,进行隐形墨水实验,实验操作安全、简单,字迹显示清晰,用时恰当,是一个合适的课外活动实验。 相似文献
995.
Prof. Junghoon Lee So‐Huei Kang Sang Myeon Lee Dr. Kyu Cheol Lee Heesoo Yang Yongjoon Cho Daehee Han Prof. Yongfang Li Prof. Byoung Hoon Lee Prof. Changduk Yang 《Angewandte Chemie (International ed. in English)》2018,57(41):13629-13634
To understand the effects rendered on the relevant basic physical properties and device function by controlling the regiochemistry of the cyclopenta[1,2‐b:5,4‐b′]dithiophene‐fluorobenzo[c][1,2,5]thiadiazole polymer (hereafter referred to as the CDT‐FBT polymer), two polymers, the regiorandom polymer (RA) and regioregular version (RR), respectively, are synthesized and characterized. In addition, an efficient route for synthesizing a key monomer for RR using various synthesis scope and optimizing the reaction conditions is discussed. Although RA exhibits optical, electrochemical, and morphological properties similar to RR, it shows better field‐effect transistor (FET) performance. Surprisingly, by employing a capillarity‐mediated sandwich‐casting process on a nanogrooved substrate, an unprecedented mobility of 17.8 cm2 V?1 s?1 is obtained for RA‐based FETs; this mobility value is almost twofold greater than those of the corresponding RR‐based FETs. For the first time, this study challenges previously reported results in that high carrier mobility is related to the high degree of polymer order induced by the backbone regioregularity. 相似文献
996.
Suresh Kumar Krishnammagari Byung Gwon Cho 《Phosphorus, sulfur, and silicon and the related elements》2018,193(5):306-316
Synthesis of 2-amino-4H-chromen-4-ylphosphonate derivatives has been accomplished by the one-pot three-component reaction of salicylaldehyde, malononitrile/ethylcyanoacetate and dialkyl phosphites in the presence of reusable deep eutectic solvent (DES) under mild conditions. The advantages of this method are mild reaction conditions, simple work-up procedure, use of DES as a green solvent and an economical protocol for the preparation of important biologically active phosphorus-containing compounds. 相似文献
997.
Insub Jung Haneul Yoo Dr. Hee‐Jeong Jang Dr. Sanghyun Cho Kyungeun Lee Prof. Dr. Seunghun Hong Prof. Dr. Sungho Park 《Angewandte Chemie (International ed. in English)》2018,57(7):1841-1845
An unprecedented active and dynamic sensing platform based on a LSPR configuration that is modulated by using an external magnetic field is reported. Electrochemically synthesized Au/Fe/Au nanorods exhibited plasmonically active behavior through plasmonic coupling, and the middle ferromagnetic Fe block responded to a magnetic impetus, allowing the nanorods to be modulated. The shear force variation induced by the specific binding events between antigens and antibodies on the nanorod surface is used to enhance the sensitivity of detection of antigens in the plasmonics‐based sensor application. As a proof‐of‐concept, influenza A virus (HA1) was used as a target protein. The limit of detection was enhanced by two orders of magnitude compared to that of traditional LSPR sensing. 相似文献
998.
We have designed and synthesised new anion receptors 1 and 2, both of their C–H groups were at the α positions to carbonyl groups and further polarised by the attached polarising substituents. This enabled us to study hydrogen bonding donor ability of C–H bonds. The polarising substituents are electron withdrawing cyano group for host 1, while charged pyridinium group for host 2. As expected from charge effects, host 2 shows roughly an order of magnitude higher binding constants against various anion guests than those of receptor 1. Since the magnitude of polarisation change should be greatest for C–H group among various hydrogen bonding groups, this indicates the importance of C–H hydrogen bonding. In contrast, the relative order of binding constants was the same for both host 1 and 2. The order of association constants was found to be (CH3)2POO? > CH3COO? > C6H5COO? > Cl? > Br?. DFT calculation results were in good agreement with experimental binding constants and confirmed the importance of charged group substitution. In addition, receptor 1 showed the highest association constant for dimethyl phosphinate, which is implicated in many metabolic diseases. 相似文献
999.
A Supramolecular Hydrogel Based on Polyglycerol Dendrimer‐Specific Amino Group Recognition
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Dendrimer‐based supramolecular hydrogels have gained attention in biomedical fields. While biocompatible dendrimers were used to prepare hydrogels via physical and/or chemical crosslinking, smart functions such as pH and molecular control remain undeveloped. Here, we present polyglycerol dendrimer‐based supramolecular hydrogel formation induced by a specific interaction between the polyglycerol dendrimer and an amino group of glycol chitosan. Gelation was achieved by mixing the two aqueous solutions. Hydrogel formation was controlled by varying the polyglycerol dendrimer generation. The hydrogel showed pH‐dependent swelling; strongly acidic conditions induced degradation via dissociation of the specific interaction. It also showed unique l ‐arginine‐responsive degradation capability due to competitive exchange of the amino groups of glycol chitosan and l ‐arginine. These polyglycerol dendrimer‐based supramolecular characteristics allow multimodal application in smart biomaterials. 相似文献
1000.
An efficient and benign method for the preparation of aminomethyl-substituted fullerenes has been developed. The process, involving catalyst free, visible-light irradiation of 10% EtOH-toluene solutions containing fullerene C60 and N-trimethylsilylmethyl-substituted amines by using a 20 W compact fluorescent lamp, leads to formation of aminomethyl-substituted fullerene adducts in a highly efficient manner. The photoaddition reaction takes place via a pathway initiated by visible light absorption by C60, followed by SET from the amine to the triplet excited state of C60. Ethanol-promoted desilylation of the resulting a minimum radical then generates the corresponding α-amino radical which couples with the C60 radical anion to form the anion precursor of the fullerene adducts. The new approach using visible-light takes place under mild conditions and it does not require the use of photocatalysts. Thus, the method developed in this effort could broadens the range of functionalized fullerene derivatives that can be readily prepared. 相似文献