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991.
Wei-Ting Chen Wei-Chun Chen Kuang-Hua Hsueh Chen-Wei Chiu Chi-Min Shu 《Journal of Thermal Analysis and Calorimetry》2014,118(2):1085-1094
The rapid development of the petrochemical industry of Taiwan over the past four decades has resulted in a booming economy in Taiwan that drives derived industries to develop progressively. However, it has also caused many runaway reaction accidents, such as toxic gas release, fire, and explosion. It is crucial to eliminate those potential hazard factors which can induce consequent runaway reaction accidents during the life span of the manufacturing process. In response to this crucial issue, we performed a thermokinetic parameter analysis for 1,1-bis-(tert-butylperoxy)-3,3,5-trimethylcyclohexane at isothermal conditions to conduct a thermal safety assessment of chemical materials. The five isothermal temperatures, 90, 100, 110, 120, 130, and 140 °C, measured by DSC, were adopted in this study to calculate process safety parameters, including TMRad, T NR, and SADT, which can be employed in process safety parameters for the manufacturing process. A novel, green kinetic approach accompanied with non-isothermal DSC results is used to derive thermokinetic parameters in safety protocol in this study. 相似文献
992.
Guishan Zou Xiukang Yang Xianyou Wang Long Ge Hongbo Shu Yansong Bai Chun Wu Haipeng Guo Liang Hu Xin Yi Bowei Ju Hai Hu Di Wang Ruizhi Yu 《Journal of Solid State Electrochemistry》2014,18(7):1789-1797
The Li-rich Li1.3[Ni0.35Mn0.65]O2+x microspheres are firstly prepared and subsequently transferred into the Al2O3-coated Li-rich Li1.3[Ni0.35Mn0.65]O2+x microspheres by a simple deposition method. The as-prepared samples are characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and charge/discharge tests. The results reveal that the Al2O3-coated Li-rich Li1.3[Ni0.35Mn0.65]O2+x sample has a typical α-NaFeO2 layered structure with the existence of Li2MnO3-type integrated component, and the Al2O3 layer is uniformly coated on the surface of the spherical Li-rich Li1.3[Ni0.35Mn0.65]O2+x particles with a thickness of about 4 nm. Importantly, the Al2O3-coated Li-rich sample exhibits obviously improved electrochemical performance compared with the pristine one, especially the 2 wt.% Al2O3-coated sample shows the best electrochemical properties, which delivers an initial discharge capacity of 228 mAh g?1 at a rate of 0.1 C in the voltage of 2.0–4.6 V, and the first coulombic efficiency is up to 90 %. Furthermore, the 2 wt.% Al2O3-coated sample represents excellent cycling stability with capacity retention of 90.9 % at 0.33 C after 100 cycles, much higher than that of the pristine one (62.2 %). Particularly, herein, the typical inferior rate capability of Li-rich layered cathode is apparently improved, and the 2 wt.% Al2O3-coated sample also shows a high rate capability, which can deliver a capacity of 101 mAh g?1 even at 10 C. Besides, the thin Al2O3 layer can reduce the charge transfer resistance and stabilize the surface structure of active material during cycling, which is responsible for the improvement of electrochemical performance of the Li-rich Li1.3[Ni0.35Mn0.65]O2+x . 相似文献
993.
Metal Oxide‐Coated Three‐Dimensional Graphene Prepared by the Use of Metal–Organic Frameworks as Precursors
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Xianhong Rui Wenhui Shi Prof. Qingyu Yan Prof. Hua Zhang 《Angewandte Chemie (International ed. in English)》2014,53(5):1404-1409
A simple method for the preparation of metal‐oxide‐coated three‐dimensional (3D) graphene composites was developed. The metal–organic frameworks (MOFs) that served as the precursors of the metal oxides were first synthesized on the 3D graphene networks (3DGNs). The desired metal oxide/3DGN composites were then obtained by a two‐step annealing process. As a proof‐of‐concept application, the obtained ZnO/3DGN and Fe2O3/3DGN materials were used in a photocatalytic reaction and a lithium‐ion battery, respectively. We believe this method could be extended to the synthesis of other metal oxide/3DGN composites with 3D structures simply through the appropriate choice of specific MOFs as precursors. 相似文献
994.
Multi‐Colored Fibers by Self‐Assembly of DNA,Histone Proteins,and Cationic Conjugated Polymers
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Fengyan Wang Zhang Liu Bing Wang Dr. Liheng Feng Prof. Libing Liu Prof. Fengting Lv Prof. Yilin Wang Prof. Shu Wang 《Angewandte Chemie (International ed. in English)》2014,53(2):424-428
The development of biomolecular fiber materials with imaging ability has become more and more useful for biological applications. In this work, cationic conjugated polymers (CCPs) were used to construct inherent fluorescent microfibers with natural biological macromolecules (DNA and histone proteins) through the interfacial polyelectrolyte complexation (IPC) procedure. Isothermal titration microcalorimetry results show that the driving forces for fiber formation are electrostatic and hydrophobic interactions, as well as the release of counterions and bound water molecules. Color‐encoded IPC fibers were also obtained based on the co‐assembly of DNA, histone proteins, and blue‐, green‐, or red‐ (RGB‐) emissive CCPs by tuning the fluorescence resonance energy‐transfer among the CCPs at a single excitation wavelength. The fibers could encapsulate GFP‐coded Escherichia coli BL21, and the expression of GFP proteins was successfully regulated by the external environment of the fibers. These multi‐colored fibers show a great potential in biomedical applications, such as biosensor, delivery, and release of biological molecules and tissue engineering. 相似文献
995.
The hydration of NaCl has been widely studied and believed to be important for understanding the mechanisms of salt dissolution in water and the formation of ice nucleus, cloud, and atmospheric aerosols. However, understanding on the poly-NaCl ion pair interacting with water is very limited. Here, we investigated the adsorption of water molecules on (NaCl)3, using both theoretical calculations and anion photoelectron spectroscopy measurements. The calculated vertical detachment energies and the experimental ones agree well with each other. Furthermore, we found that, for neutral (NaCl)3(H2O) n (n = 2–7) clusters, the water-doped cuboid and structures formed by adding water molecules on the Na–Cl edges of the cuboid are energetically favored; water molecules preferentially bind to the Na–Cl edge if the NaCl ion pair has larger partial charges than others. We also found the anionic structures are more various compared with neutral ones, and the Na+ and Cl? ions are hydrated more easily in the anionic clusters than in the corresponding neutrals. 相似文献
996.
Electrochemical Synthesis of Tetrahexahedral Rhodium Nanocrystals with Extraordinarily High Surface Energy and High Electrocatalytic Activity
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Neng‐Fei Yu Dr. Na Tian Dr. Zhi‐You Zhou Long Huang Jing Xiao Yu‐Hua Wen Prof. Shi‐Gang Sun 《Angewandte Chemie (International ed. in English)》2014,53(20):5097-5101
Noble metal nanocrystals (NCs) enclosed with high‐index facets hold a high catalytic activity thanks to the high density of low‐coordinated step atoms that they exposed on their surface. Shape‐control synthesis of the metal NCs with high‐index facets presents a big challenge owing to the high surface energy of the NCs, and the shape control for metal Rh is even more difficult because of its extraordinarily high surface energy in comparison with Pt, Pd, and Au. The successful synthesis is presented of tetrahexahedral Rh NCs (THH Rh NCs) enclosed by {830} high‐index facets through the dynamic oxygen adsorption/desorption mediated by square‐wave potential. The results demonstrate that the THH Rh NCs exhibit greatly enhanced catalytic activity over commercial Rh black catalyst for the electrooxidation of ethanol and CO. 相似文献
997.
Pumping through Porous Hydrophobic/Oleophilic Materials: An Alternative Technology for Oil Spill Remediation
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Jin Ge Yin‐Dong Ye Hong‐Bin Yao Xi Zhu Xu Wang Liang Wu Jin‐Long Wang Prof. Hang Ding Prof. Ni Yong Prof. Ling‐Hui He Prof. Dr. Shu‐Hong Yu 《Angewandte Chemie (International ed. in English)》2014,53(14):3612-3616
Recently, porous hydrophobic/oleophilic materials (PHOMs) have been shown to be the most promising candidates for cleaning up oil spills; however, due to their limited absorption capacity, a large quantity of PHOMs would be consumed in oil spill remediation, causing serious economic problems. In addition, the complicated and time‐consuming process of oil recovery from these sorbents is also an obstacle to their practical application. To solve the above problems, we apply external pumping on PHOMs to realize the continuous collection of oil spills in situ from the water surface with high speed and efficiency. Based on this novel design, oil/water separation and oil collection can be simultaneously achieved in the remediation of oil spills, and the oil sorption capacity is no longer limited to the volume and weight of the sorption material. This novel external pumping technique may bring PHOMs a step closer to practical application in oil spill remediation. 相似文献
998.
Molecular Engineering of Push–Pull Porphyrin Dyes for Highly Efficient Dye‐Sensitized Solar Cells: The Role of Benzene Spacers
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Shaik M. Zakeeruddin Shu‐Nung Chang Chi‐Hung Hsieh Chen‐Yu Yeh Michael Grätzel 《Angewandte Chemie (International ed. in English)》2014,53(11):2973-2977
Porphyrins have drawn much attention as sensitizers owing to the large absorption coefficients of their Soret and Q bands in the visible region. In a donor and acceptor zinc porphyrin we applied a new strategy of introducing 2,1,3‐benzothiadiazole (BTD) as a π‐conjugated linker between the anchoring group and the porphyrin chromophore to broaden the absorption spectra to fill the valley between the Soret and Q bands. With this novel approach, we observed 12.75 % power‐conversion efficiency under simulated one‐sun illumination (AM1.5G, 100 mW cm?2). In this study, we showed the importance of introducing the phenyl group as a spacer between the BTD and the zinc porphyrin in achieving high power‐conversion efficiencies. Time‐resolved fluorescence, transient‐photocurrent‐decay, and transient‐photovoltage‐decay measurements were employed to determine the electron‐injection dynamics and the lifetime of the photogenerated charge carriers. 相似文献
999.
Dr. Chunxiu Hua Dr. Xiangpeng Fang Prof. Zhaoxiang Wang Prof. Liquan Chen 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(18):5487-5491
It is well accepted that metallic tin as a discharge (reduction) product of SnOx cannot be electrochemically oxidized below 3.00 V versus Li+/Li0 due to the high stability of Li2O, though a similar oxidation can usually occur for a transition metal formed from the corresponding oxide. In this work, nanosized Ni2SnO4 and NiO/SnO2 nanocomposite were synthesized by coprecipitation reactions and subsequent heat treatment. Owing to the catalytic effect of nanosized metallic nickel, metallic tin can be electrochemically oxidized to SnO2 below 3.00 V. As a result, the reversible lithium‐storage capacities of the nanocomposite reach 970 mAh g?1 or above, much higher than the theoretical capacity (ca. 750 mAh g?1) of SnO2, NiO, or their composites. These findings extend the well‐known electrochemical conversion reaction to non‐transition‐metal compounds and may have important applications, for example, in constructing high‐capacity electrode materials and efficient catalysts. 相似文献
1000.
Back Cover: Two‐Dimensional Tetrathiafulvalene Covalent Organic Frameworks: Towards Latticed Conductive Organic Salts (Chem. Eur. J. 45/2014)
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