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101.
102.
103.
双硫腙改性的聚(二甲基丙烯酸乙二醇酯-甲基丙烯酸羟乙酯)微球的制备及其对铜离子的吸附研究 总被引:1,自引:0,他引:1
用悬浮聚合法由二甲基丙烯酸乙二醇酯(EGDMA)和甲基丙烯酸羟乙酯(HEMA)共聚制备得到聚(二甲基丙烯酸乙二醇酯-甲基丙烯酸羟乙酯)(PHEMA)微球,考察了NaOH浓度、反应时间等对用双硫腙进行PHEMA改性反应的影响以及铜离子水溶液浓度(5~500mg/L)、pH(2.0~6.5)、吸附时间等对改性后的微球对铜离子吸附性能影响的因素.改性的PHEMA微球对铜离子的最大吸附量为65.6mg铜离子/g双硫腙;而且,吸附有铜离子的改性PHEMA微球用0.1mol/L的硝酸的解吸率可达到90%以上,经过3次吸附-解吸循环后,解吸率仍基本不变,这表明双硫腙改性的PHEMA微球可以多次反复使用,具有良好的应用前景. 相似文献
104.
Tian R Jiang X Li X Jiang X Feng S Xu S Han G Ye M Zou H 《Journal of chromatography. A》2006,1134(1-2):134-142
In this study, a gel free chemiproteomic method based on chromatography was developed and applied for the biological fingerprinting analysis of complex biological system. p-Aminobenzamidine (ABA), an inhibitor of trypsin-like serine proteases, was immobilized for characterizing their interacting proteins in human plasma. By the proteomic analysis method, 214 proteins were identified with obvious affinity to the immobilized ABA. By searching the sequences of above proteins with consensus patterns of the two active sites, seven proteins belong to trypsin-like serine protease group were found. Based on the Gene Ontology annotation, the identified trypsin-like serine proteases have the function of catalytic activity and calcium ion binding, and are mainly involved in the biological process of blood coagulation. Eight more other proteins related to calcium ion binding and blood coagulation were found. Nearly all of these proteins cannot be identified by directly analyzing the plasma sample demonstrating the chemiproteomics a useful approach to characterize interacting proteins in the low abundance range. 相似文献
105.
以草酸铵和醋酸锌为原料,采用直接沉淀法制备ZnO粉体,考察了焙烧温度对粉体结晶和光学性能的影响。 采用热重分析(TGA-DTA)、X射线衍射、紫外-可见漫反射(UV-Vis)、荧光分光光度计(FS)和扫描电子显微镜(SEM)等方法对样品进行了分析。 结果表明,制备的前驱物为C2O4Zn·2H2O,最低焙烧温度400 ℃,随着焙烧温度的提高,粉体结晶度提高,一次粒径增大;600 ℃焙烧后有较强紫外发光峰,粉体由200 nm的粒子排列成层叠状;900 ℃焙烧后有较强可见发光峰,粉体粒子大于500 nm,团聚严重;粉体有较强的紫外吸收,吸收峰有蓝移。 相似文献
106.
Transition metal dichalcogenides (TMD) MoS2 or graphene could be designed to metallic nanoribbons, which always have only one edge show metallic properties due to symmetric protection. In present work, a nanoribbon with two parallel metallic and magnetic edges was designed from a noble TMD PtS2 by employing first-principles calculations based on density functional theory (DFT). Edge energy, bonding charge density, band structure, density of states (DOS) and simulated scanning tunneling microscopy (STM) of four possible edge states of monolayer semiconductive PtS2 were systematically studied. Detailed calculations show that only Pt-terminated edge state among four edge states was relatively stable, metallic and magnetic. Those metallic and magnetic properties mainly contributed from 5d orbits of Pt atoms located at edges. What's more, two of those central symmetric edges coexist in one zigzag nanoribbon, which providing two atomic metallic wires thus may have promising application for the realization of quantum effects, such as Aharanov–Bohm effect and atomic power transmission lines in single nanoribbon. 相似文献
107.
令$K_{n}^{c}$表示$n$ 个顶点的边染色完全图.
令 $\Delta^{mon}
(K_{n}^{c})$表示$K^c_{n}$的顶点上关联的同种颜色的边的最大数目.
如果$K_{n}^{c}$中的一个圈(路)上相邻的边染不同颜色,则称它为正常染色的.
B. Bollob\'{a}s和P. Erd\"{o}s (1976) 提出了如下猜想:若 $\Delta^{{mon}}
(K_{n}^{c})<\lfloor \frac{n}{2} \rfloor$, 则$K_{n}^{c}$中含有一个正常染
色的Hamilton圈. 这个猜想至今还未被证明.我们研究了上述条件下的正常染色的路和圈. 相似文献
108.
109.
Feng Xiong Yan‐Yan Yu Zongfang Wu Guanghui Sun Liangbing Ding Yuekang Jin Prof. Dr. Xue‐Qing Gong Prof. Dr. Weixin Huang 《Angewandte Chemie (International ed. in English)》2016,55(2):623-628
Exploring reactions of methanol on TiO2 surfaces is of great importance in both C1 chemistry and photocatalysis. Reported herein is a combined experimental and theoretical calculation study of methanol adsorption and reaction on a mineral anatase TiO2(001)‐(1×4) surface. The methanol‐to‐dimethyl ether (DME) reaction was unambiguously identified to occur by the dehydration coupling of methoxy species at the fourfold‐coordinated Ti4+ sites (Ti4c), and for the first time confirms the predicted higher reactivity of this facet compared to other reported TiO2 facets. Surface chemistry of methanol on the anatase TiO2(001)‐(1×4) surface is seldom affected by co‐chemisorbed water. These results not only greatly deepen the fundamental understanding of elementary surface reactions of methanol on TiO2 surfaces but also show that TiO2 with a high density of Ti4c sites is a potentially active and selective catalyst for the important methanol‐to‐DME reaction. 相似文献
110.
Platelets contribute a major role in hemostasis by clumping and coagulation at the site of blood vessel injuries.In light of recent findings of a close relation... 相似文献