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161.
便携式野外净水装置为人们在野外获得安全饮用水提供了极大便利.综述了便携式净水器的净水材料、净水工艺和结构设计特点,分析了野外便携式净水设备的优缺点,并提出采用低压高效的膜材料将是野外便携式净水设备的发展方向. 相似文献
162.
Extraction and analysis of extracellular polymeric substances in membrane fouling in submerged MBR 总被引:3,自引:0,他引:3
The extraction and analysis of EPS in active biomass and membrane fouling were performed to investigate the influence of extracellular polymeric substances (EPS) on membrane fouling of MBR. The new membrane and fouling membrane surface morphology was characterized by EDX analysis. The results show that membrane contaminant is mainly composed of organic compounds. EPS in active biomass and membrane pollutant were extracted by method of alkaline regular centrifugation. Most of EPS were found to have high molecular weight over 12,000 D, which is very difficult to degrade. The total EPS contents in the extracted solution and the contents of polysaccharide protein and DNA in EPS were respectively analysed with TOC analysis and by phenol-sulfuric acid method, modification of the Bradford method and the fluorometric method. The analytical results indicate that the content of EPS in membrane fouling is about four times as much as that in active biomass, and polysaccharide is the most important pollutant on membrane, as well as protein’s role in membrane fouling is not negligible, whereas the DNA is not important in membrane fouling because of its content (non-dialysis) in membrane contaminant being less than that in the active biomass. In addition, the results in electrophoresis experiment provide the information about the concentrated distribution of molecular weight of large fragment DNA in both membrane contaminant and the biomass. 相似文献
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164.
Taishi Yokoi Masakazu Kawashita Koichi Kikuta Chikara Ohtsuki 《Materials science & engineering. C, Materials for biological applications》2010,30(1):154-159
Calcium phosphate crystals were synthesized in polyacrylamide (PAAm) hydrogel, and the effects of the concentrations of calcium and phosphate ions on the crystalline phases and morphology were investigated. PAAm hydrogels containing diammonium hydrogen phosphate ((NH4)2HPO4) were transformed into calcified materials by diffusion of calcium ions from calcium nitrate (Ca(NO3)2) aqueous solution into the gels. Several kinds of calcium phosphate crystals were precipitated at various Ca(NO3)2 concentrations (0.5–4.0 mol·dm? 3), or (NH4)2HPO4 contents (3.6–21.6 mmol) in the gels. The crystalline phases were mainly determined by the (NH4)2HPO4 content in the gels. When the (NH4)2HPO4 content was ≥ 10.8 mmol, hydroxyapatite (HAp) formed near the interfaces between Ca(NO3)2 solution and the gels, whereas octacalcium phosphate (OCP) formed in gels with ≤ 10.8 mmol (NH4)2HPO4. HAp crystals were granular in form and about 200 nm in diameter, and OCP crystals were spherulitic with diameter 10–70 μm. 相似文献
165.
Yan Zhang Keisuke Shinokita Kenji Watanabe Takashi Taniguchi Masato Goto Daisuke Kan Yuichi Shimakawa Yutaka Moritomo Taishi Nishihara Yuhei Miyauchi Kazunari Matsuda 《Advanced materials (Deerfield Beach, Fla.)》2020,32(50):2003501
Optically generated excitonic states (excitons and trions) in transition metal dichalcogenides are highly sensitive to the electronic and magnetic properties of the materials underneath. Modulation and control of the excitonic states in a novel van der Waals (vdW) heterostructure of monolayer MoSe2 on double-layered perovskite Mn oxide ((La0.8Nd0.2)1.2Sr1.8Mn2O7) is demonstrated, wherein the Mn oxide transforms from a paramagnetic insulator to a ferromagnetic metal. A discontinuous change in the exciton photoluminescence intensity via dielectric screening is observed. Further, a relatively high trion intensity is discovered due to the charge transfer from metallic Mn oxide under the Curie temperature. Moreover, the vdW heterostructures with an ultrathin h-BN spacer layer demonstrate enhanced valley splitting and polarization of excitonic states due to the proximity effect of the ferromagnetic spins of Mn oxide. The controllable h-BN thickness in vdW heterostructures reveals a several-nanometer-long scale of charge transfer as well as a magnetic proximity effect. The vdW heterostructure allows modulation and control of the excitonic states via dielectric screening, charge carriers, and magnetic spins. 相似文献
166.
High Current Injection into Dynamic p–n Homojunction in Polymer Light‐Emitting Electrochemical Cells 下载免费PDF全文
Tomo Sakanoue Jinpeng Li Hisaaki Tanaka Ryota Ito Shimpei Ono Shin‐ichi Kuroda Taishi Takenobu 《Advanced materials (Deerfield Beach, Fla.)》2017,29(18)
Ions and electrons in blends of polymer–electrolyte can work in ensemble to operate light‐emitting electrochemical cells (LECs), in which the unique features of in situ formed p–n homojunctions offer efficient charge injection and transport. However, electrochemical features give rise to significant stability and speed issues due to limited electrochemical stability and low ion mobility, resulting in low brightness and a slow response of LECs. Here, these issues are overcome by the separate control of ionic and electronic charges, using a simple driving pulse superimposed on a small base voltage; ions with slow response are rearranged by a constant base voltage, while a high‐voltage pulse, superimposed upon the base, injects electrons/holes which have fast response, with minimal effect on the ions. This scheme successfully injects an extremely high current density of > 2 kA cm?2 with a balanced electron/hole ratio, at a high‐speed response time of ≈ 50 ns; both properties demonstrate advantages of LECs in making polymers brighter. An in situ electron spin resonance measurement on the LECs further revealed that this impressive performance is due to the highly doped polymers, whose spin density reached 7 × 1019 spins cm?3, and an ordered polymer structure in the active layer blend. 相似文献
167.
A Versatile and Simple Approach to Generate Light Emission in Semiconductors Mediated by Electric Double Layers 下载免费PDF全文
Jiang Pu Taiyo Fujimoto Yuki Ohasi Shota Kimura Chang‐Hsiao Chen Lain‐Jong Li Tomo Sakanoue Taishi Takenobu 《Advanced materials (Deerfield Beach, Fla.)》2017,29(24)
The light‐emitting device is the primary device for current light sources. In principle, conventional light‐emitting devices need heterostructures and/or intentional carrier doping to form a p–n junction. This junction formation is, however, very difficult to achieve for most emerging semiconductors, and the fabrication of light‐emitting devices is invariably a significant challenge. This study proposes a versatile and simple approach to realize light‐emitting devices. This proposed device requires only a semiconducting film with two electrodes that are covered with an electrolyte. This unique structure achieves light emission at a voltage slightly larger than the bandgap energy of materials. This study applies this concept to emerging direct bandgap semiconductors, such as transition metal dichalcogenide monolayers and zinc oxide single crystals. These devices generate obvious light emission and provide sufficient evidence of the formation of a dynamic p–i–n junction or tunneling junction, presenting a versatile technique to develop optoelectronic devices. 相似文献
168.
169.
Kosaka T Okuyama R Sun W Ogata T Harada J Araki K Izumi M Yoshida T Okuno A Fujiwara T Ohsumi J Ichikawa K 《Analytical chemistry》2005,77(7):2050-2055
We show an efficient method to identify molecular targets of small molecular compounds by affinity purification and mass spectrometry. Binding proteins were isolated from target cell lysate using affinity columns, which immobilized the active and inactive compounds. All proteins bound to these affinity columns were eluted by digestion using trypsin and then were identified by mass spectrometry. The specific binding proteins to the active compound, a candidate for molecular targets, were determined by subtracting the identified proteins in an inactive compound-immobilized affinity column from that in an active compound-immobilized affinity column. This method was applied to identification of molecular targets of D942, a furancarboxylic acid derivative, which increases glucose uptake in L6 myocytes through AMP-activated protein kinase (AMPK) activation. To elucidate the mechanism of AMPK activation by D942, affinity columns that immobilized D942 and its inactive derivative, D768, were prepared, and the binding proteins were purified from L6 cell lysate. NAD(P)H dehydrogenase [quinone] 1 (complex I), which was shown as one of the specific binding proteins to D942 by subtracting the binding proteins to D768, was partially inhibited by D942, not D768. Because inhibition of complex I activity led to a decrease in the ATP/AMP ratio, and the change in the ATP/AMP ratio triggered AMPK activation, we identified complex I as a potential protein target of AMPK activation by D942. This result shows our approach can provide crucial information about the molecular targets of small molecular compounds, especially target proteins not yet identified. 相似文献
170.
S. Kobayashi T. Takenobu S. Mori A. Fujiwara Y. Iwasa 《Science and Technology of Advanced Materials》2013,14(4):371-375
We report performance of C60 thin-film field-effect transistors and characterizations of C60 thin-films on SiO2 substrates fabricated by molecular beam deposition. Devices, fabricated and characterized under high vacuum without exposing to air, routinely showed current on/off ratios >108 and field-effect mobility in the range of 0.5–0.3 cm2/V s. The obtained mobility is comparable to the highest value among n-type organic thin-film transistors and close to that derived from the photocurrent measurements on C60 thin-films.The grain size of C60 thin-film, condensed in an fcc solid, increases with the substrate temperature, while themobility did not exhibit a clear relation with substrate temperature.© 2003 Elsevier Ltd. All rights reserved. 相似文献