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51.
Synthesis of fluorescent and low cytotoxicity phenol formaldehyde resin (PFR)@Ag composites for cell imaging and antibacterial activity 下载免费PDF全文
Ping Yang Hao Dong Jun Xia Andong Xu Jianjun Shi Jie He Jianzhong Ding Dewei Li 《Luminescence》2015,30(8):1413-1417
Ag nanoparticles (NPs) were loaded onto the surface of phenol formaldehyde resin (PFR) NPs without any reducing agent. The as‐synthesized PFR@Ag composites have low cytotoxicity, which makes them promising antibacterial agents. Furthermore, the good fluorescence of PFR could be used for cell imaging. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
52.
为了快速鉴别饲料中的狐狸、水貂、貉子和狗源性成分,根据线粒体16S r DNA种间保守序列,设计合成针对狐狸、水貂、貉子和狗的特异性引物和探针,通过对荧光PCR反应体系和反应条件的优化筛选,建立了多重实时荧光PCR方法,在同一PCR反应体系中可以同时完成4种动物源性成分检测。通过对15种其他物种的源性成分的检测,结果表明所设计的引物和探针具有很好的物种特异性,且灵敏度高,狐狸、水貂、貉子和狗的DNA检出限为0.01ng。对40份样品检测,其中5份检测出貉子、狐狸和水貂源性成分。结果表明,该方法可以有效地鉴别出饲料中狐狸、水貂、貉子和狗源性成分,同时适用于相关动物产品中。 相似文献
53.
Extended producer responsibility (EPR) is a policy approach that requires manufacturers to finance the costs of recycling or safely disposing of products consumers no longer want. This article describes the evolution of EPR policies in the United States, focusing on the role of states as policy actors. For their part, federal lawmakers have not embraced EPR policies except to remove some barriers to state‐level initiatives. In the two‐decade period from 1991 to 2011, U.S. states enacted more than 70 EPR laws. In addition, manufacturers have implemented voluntary programs to collect and recycle products, but those efforts have proven largely ineffective in capturing significant quantities of waste products. With the help of new coalitions of diverse interest groups, recently states have renewed efforts to establish effective EPR programs, enacting 40 laws in the period 2008–2011. Several state initiatives suggest a more promising future for EPR. 相似文献
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Shuai Liu Zepeng Liu Xi Shen Xuelong Wang Sheng‐Chieh Liao Richeng Yu Zhaoxiang Wang Zhiwei Hu Chien‐Te Chen Xiqian Yu Xiaoqing Yang Liquan Chen 《Liver Transplantation》2019,9(32)
Li‐rich layered metal oxides are one type of the most promising cathode materials in lithium‐ion batteries but suffer from severe voltage decay during cycling because of the continuous transition metal (TM) migration into the Li layers. A Li‐rich layered metal oxide Li1.2Ti0.26Ni0.18Co0.18Mn0.18O2 (LTR) is hereby designed, in which some of the Ti4+ cations are intrinsically present in the Li layers. The native Li–Ti cation mixing structure enhances the tolerance for structural distortion and inhibits the migration of the TM ions in the TMO2 slabs during (de)lithiation. Consequently, LTR exhibits a remarkable cycling stability of 97% capacity retention after 182 cycles, and the average discharge potential drops only 90 mV in 100 cycles. In‐depth studies by electron energy loss spectroscopy and aberration‐corrected scanning transmission electron microscopy demonstrate the Li–Ti mixing structure. The charge compensation mechanism is uncovered with X‐ray absorption spectroscopy and explained with the density function theory calculations. These results show the superiority of introducing transition metal ions into the Li layers in reinforcing the structural stability of the Li‐rich layered metal oxides. These findings shed light on a possible path to the development of Li‐rich materials with better potential retention and a longer lifespan. 相似文献
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The German government has adopted a law that requires sewage plants to go beyond the recovery of phosphorus from wastewater and to promote recycling. We argue that there is no physical global short‐ or mid‐term phosphorus scarcity. However, we also argue that there are legitimate reasons for policies such as those of Germany, including: precaution as a way to ensure future generations’ long‐term supply security, promotion of technologies for closed‐loop economics in a promising stage of technology development, and decrease in the current supply risk with a new resource pool. 相似文献
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生物来源的胶原蛋白、明胶、纤维蛋白原、纤维素、淀粉以及壳聚糖等材料,因为其无毒性、良好的生物相容性、生物可降解性以及促凝血活性越来越受到研究者的青睐,成为更加优异的止血选择。本文综述目前止血材料的几种类型及相应的止血机理,重点讨论上述生物来源止血材料的基本结构、止血机理、市售产品及最新科研进展,并对其发展前景进行展望。 相似文献
59.
Synthesis of novel Dy3+ activated Ba2CaZn2Si6O17 phosphors for white light‐emitting diodes 下载免费PDF全文
Dysprosium ion (Dy3+) activated Ba2CaZn2Si6O17 phosphors were synthesized using high temperature solid‐state reaction method. Powder X‐ray diffraction (PXRD) analysis confirmed the phase formation of the as‐prepared phosphors. Scanning electron microscopy (SEM) analysis disclosed an agglomeration of particles with an irregular morphology. Under 350 nm excitation, the emission spectrum of Dy3+ ions showed bands at 481 nm (blue), 577 nm (yellow) and 674 nm (red). The influence of the Dy3+ concentration on its emission intensity was investigated. The optimum concentration of Dy3+ ions in the Ba2CaZn2Si6O17:Dy3+ phosphors were found to be x = 0.06. The critical energy transfer distance was calculated. The fluorescence lifetime was also determined for Ba2CaZn2Si6O17:0.06Dy3+. The Commission International deI’Eclairage (CIE) chromaticity coordinates of the phosphor were calculated to be x = 0.304, y = 0.382. The activation energy for the thermal quenching was calculated to be 0.168 eV. These results indicated that the Ba2CaZn2Si6O17:Dy3+ phosphor might be a potential candidate for near ultraviolet (NUV)‐based white light‐emitting diodes. 相似文献
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Haegyeom Kim Min‐Young Cho Mok‐Hwa Kim Kyu‐Young Park Hyeokjo Gwon Yunsung Lee Kwang Chul Roh Kisuk Kang 《Liver Transplantation》2013,3(11):1500-1506
A hybrid supercapacitor with high energy and power densities is reported. It comprises a composite anode of anatase TiO2 and reduced graphene oxide and an activated carbon cathode in a non‐aqueous electrolyte. While intercalation compounds can provide high energy typically at the expense of power, the anatase TiO2 nanoparticles are able to sustain both high energy and power in the hybrid supercapacitor. At a voltage range from 1.0 to 3.0 V, 42 W h kg?1 of energy is achieved at 800 W kg?1. Even at a 4‐s charge/discharge rate, an energy density as high as 8.9 W h kg?1 can be retained. The high energy and power of this hybrid supercapacitor bridges the gap between conventional batteries with high energy and low power and supercapacitors with high power and low energy. 相似文献