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Tang Guangxian Shafee Ahmad Nam Nguyen Dang Tlili Iskander 《Journal of Thermal Analysis and Calorimetry》2021,143(6):4249-4260
Journal of Thermal Analysis and Calorimetry - Electrical sensor has been considered in the current attempt. Combination of buoyancy, electric and radiative forces has been included in the governing... 相似文献
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Yu Na Lim Soo Kyung Chae Woongbin Yim Ji‐Yong Park Woojin Yoon Hoseop Yun Eunha Kim Seung Uk Son Hye‐Young Jang 《应用有机金属化学》2019,33(3)
The reaction of [(domppp) Pd (OAc)2] [domppp = 1,3‐bis (di‐o‐methoxyphenylphosphino)propane] and imidazolium‐functionalized carboxylic acids containing various anions (Br?, PF6?, SbF6? and BF4?) resulted in the formation of nano‐sized Pd (II) aggregates under template‐free conditions. The rate of formation of aggregates can be modulated by changing the anion, affecting the rate of polymerization of CO and olefins without fouling. Herein, we describe the analysis of Pd (II) catalysts by dynamic light scattering, atomic force microscopy, X‐ray photoelectron spectroscopy and X‐ray crystallography, and co‐ and terpolymerization results including the catalytic activity, and bulk density and molecular weight of polymers. 相似文献
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Ho Van Doanh Phan Bao Quoc Hieu Pham Ngoc Son Dao Van Hoang Tam Hoang Duc Ho Manh Dung 《Journal of Radioanalytical and Nuclear Chemistry》2022,331(3):1361-1365
Journal of Radioanalytical and Nuclear Chemistry - To keep the accredited category for the gamma spectrometry test in our laboratory, the efficiency curves of a HPGe detector for soil sample in... 相似文献
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通过纳米二氧化硅的硅烷化改性, 使其在高矿化度盐水中可以稳定存在的前提下, 研究了改性纳米颗粒与阳离子表面活性剂十二烷基三甲基氯化铵混合体系的溶液稳定性及协同稳定CO2泡沫的效果. 研究结果表明, 无机盐离子对改性纳米颗粒与阳离子表面活性剂间的静电吸引力具有屏蔽作用, 且矿化度越高, 屏蔽效果越明显, 从而混合溶液更易于在高盐水中稳定; 纳米颗粒表面的活性剂吸附层受二者浓度的影响, 进而影响了颗粒的亲/疏水性; 当混合体系中的表面活性剂浓度低于临界胶束浓度(CMC)时, 混合溶液与CO2的界面张力高于单独活性剂溶液, 而当活性剂浓度高于CMC时, 对CO2-溶液界面张力几乎无影响, 最低界面张力可降至6 mN/m左右; 改性纳米颗粒的加入可以进一步提高CO2体相泡沫半衰期一倍以上, 但受二者浓度比例的影响; 纳米颗粒的加入有效提高了多孔介质中泡沫的表观黏度, 最大增幅由20 mPa·s增至55 mPa·s左右, 泡沫黏度增加接近3倍, 增强了CO2泡沫驱的封堵作用. 相似文献
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Synthesis,properties and mechanism of photodegradation of core–shell structured upconversion luminescent NaYF4:Yb3+,Er3+@BiOCl 下载免费PDF全文
Shiyu Zhou Qiyan Zhang Deqiang Zhao Wenjuan Zong Zihong Fan Yaofang Sun Xuan Xu 《应用有机金属化学》2018,32(4)
Microspherical bismuth oxychloride (BiOCl) can only utilize ultraviolet (UV) light to promote photocatalytic reactions. To overcome this limitation, a uniform and thin BiOCl nanosheet was synthesized with a particle size of about 200 nm. As results of UV–visible diffuse reflectance spectroscopy showed, the band gap of this nanostructure was reduced to 2.78 eV, indicating that the BiOCl nanosheet could absorb and utilize visible light. Furthermore, the upconversion material NaYF4 doped with rare earth ions Yb3+ and Er3+ emitted visible light at 410 nm following excitation with near‐infrared (NIR) light (980 nm), which could be utilized by BiOCl to produce a photocatalytic reaction. To produce a high‐efficiency photocatalyst (NaYF4:Yb3+,Er3+@BiOCl), BiOCl‐loaded NaYF4:Yb3+,Er3+ was successfully synthesized via a simple two‐step hydrothermal method. The as‐synthesized material was confirmed using X‐ray diffraction, scanning electron microscopy, X‐ray photoelectron spectroscopy as well as other characterizations. The removal ratio of methylene blue by NaYF4:Yb3+,Er3+@BiOCl was much higher than that of BiOCl alone. Recycling experiments verified the stability of NaYF4:Yb3+,Er3+@BiOCl, which demonstrated excellent adsorption, strong visible‐light absorption and high electron–hole separation efficiency. Such properties are expected to be useful in practical applications, and a further understanding of the NIR‐light‐responsive photocatalytic mechanism of this new catalytic material would be conducive to improving its structural design and function. 相似文献
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Data on the methods of stabilization and modification of nanosize particles used in the technology of development of new polymer-inorganic nanocomposites were analyzed and generalized. Advantages of the chemical method using silane-based surface-binding modifiers were discussed. The use of surface-initiated graft polymerization was shown to be promising for the solution of problems of deagglomeration, stabilization, and efficient homogenization of nanosize particles. 相似文献